Selective Estrogen Receptor Modulators. Antonio Cano

Chapter 9. Cardiovascular Disease and SERMs

Antonio Cano

A wealth of epidemiological, clinical, and experimental studies link estrogens with cardiovascular disease (CVD). This evidence has promoted CVD as a key area within the extragenital effects of estrogens. The question is of interest because it directly affects the wide clinical use of estrogens as contraceptive agents or as principal constituents of hormonal therapy (HT) formulations in postmenopausal women. The significance of the subject is further reinforced by the relevance of CVD as a cause of mortality and morbidity in both women and men.

CVD is a generic denomination mainly integrated by coronary heart disease (CHD) and stroke. Although not considered as a form of CVD in some instances, venous thromboembolic disease (VTED) shares with the other forms of CVD the territorial assignment, the vascular tree, although clear differences exist in the main pathophysiological mechanisms. In most CVD forms, however, thrombus formation plays a crucial role.

All forms of CVD are serious disorders, although CHD is the most prevalent and lethal. Global data in the USA attribute 54% of deaths from CVD to C HD and 18% to stroke ( Figures for Europe are similar, where about half of deaths from CVD correspond to CHD and nearly one third to stroke (British Heart Foundation 2000). The burden of the disease is also shared by developing countries where it is estimated that CVD will be the leading cause of death by 2010 (World Health Organization Web site Specific gender patterns have been detected for both the prevalence as well as the behavior of CHD, further suggesting a relevant role for reproductive hormones. Fewer differences have been found for stroke.

VTED has a lower prevalence (approximately 1/1000 persons per year), but it rises exponentially with age from < 5 cases per 100,000 persons < 15 years old to = 500 cases per 100,000 (0.5%) at age 80 years (White 2003). Against the strong gender differences found in CHD statistics, no convincing difference between men and women have been detected for VTED (Silverstein et al. 1998).

The observation that, compared with men, women maintain some level of protection against CHD has nourished the debate about a possible favorable effect associated with exposure to estrogens. Furthermore, most of the information gathered in the latter years has confirmed the association of estrogens with many benefits both in experimental as well as in clinical models at the level of intermediate indicators. Consequently, HT was proposed not only for control of symptoms but also for primary and secondary CHD prevention in postmenopausal women. Contrary to the beneficial effects found in the first, observational studies, three more recent randomized controlled trials have found that HT is neutral (Hulley et al. 1998; Anderson et al. 2004) or even prejudicial (Rossouw et al. 2002) when administered to women for the purpose of CVD prevention. The data yielded by these studies affect not only CHD but also stroke and VTED, where HT has been shown to be detrimental, too. Following this evidence, scientific societies, such as the American Heart Association, have advised against the use ofHT for the prevention ofCVD in women (Mosca et al. 2004). The mixture of protective effects, mainly at the level of risk factors and of data gathered from experimental models, as well as of neutral or prejudicial clinical outcomes defines the present picture. It is one where the confirmation of estrogens as important regulators of CVD pathophysiology emerges as a main conclusion. Consequently, selective estrogen receptor modulators (SERMs) offer a unique opportunity to achieve cardiovascular outcome profiles that might improve those attained by conventional HT.

This chapter will analyze some specific traits of CVD that will be used to review the principal variables that have exhibited sensitivity to estrogen agonism. Then, current information on the particular actions of SERMs will be presented.


The Focal Phenotype of CVD

The vascular tree is divided into two main, well-demarcated areas composed of the arterial and the venous trees. They both define different microenvironments that create the conditions for the development of focal episodes determining the occurrence of obstructive phenomena that are at the base of CVD. Arterial episodes (CHD and stroke) occur at sites of inflamed arteries, while VTED or venous stroke episodes develop as a result of thrombus formation at discrete locations in the venous tree.

Atherosclerosis, a disease of the vascular wall, is the substrate for the arterial forms of CVD. Atherosclerotic plaques exhibit a focal distribution along the arterial tree as a consequence of local conditions that favor their initiation and progression. Low or reversed shear stress, for example, contributes to plaque development, a process in which the regulation of several genes may be involved (Resnick and Gimbrone 1995).

Thrombosis is the other phenomenon that crucially contributes to both the arterial and the venous forms of CVD, although the type of thrombus,

Table 9.1. Risk factors for coronary heart disease and venous thromboembolic disease [adapted from Friedewald (1996) and Rosendaal (1999)]

Coronary heart disease

Venous thromboembolic disease





Mixed genetic and acquired


Cigarette smoking

Protein C deficiency


Increased concentration of prothrombin

Male gender

High blood pressure

Protein S deficiency


Increased concentration of factor VIII

Family history of premature disease

High blood cholesterol

Antithrombin deficiency


Hyper-homo- cystinemia


Physical inactivity Diabetes

Factor V Leiden

Prothrombin 20210A





Psychological conditions

Increased concentration of factor IX

Lupus anticoagulant Malignant disease Female hormones


Diseases affecting liver, endothelium, or other organs producing clotting factors


Abnormal dietary intake of substrates or vitamins (vitamin K)


its biological determinants, and consequently the corresponding risk factors differ for each form (Table 9.1). There is a list of factors that are involved in the increased thrombotic risk within the arterial tree (Table 9.2). Some of them directly depend on the altered focal environment, while others are systemic. The interaction between platelets and the arterial wall is one critical step. Platelet adhesion and deposition is strongly determined by local wall phenomena, essentially inflammation, with or without the substrate of an atheromatous plaque. The activation of platelets is followed by the induction of platelet coagulation activity, a process in which there is close collaboration with leukocytes adhering to the initial plug (Cano and Van Baal 2001). Liberation of tissue factor is another mechanism that participates in the generation of a thrombus.

Table 9.2. Factors affecting thrombogenicity in coronary heart disease [from Badimon et al. (1999)]

Local factors

Systemic factors

Degree of plaque disruption (i.e., erosion, ulcer)

Cholesterol, Lp(a)

Degree of stenosis


(i.e., change in geometry)

(i.e., smoking, stress, cocaine)

Tissue substrate (i.e., lipid-rich plaque)

Fibrinogen, impaired fibrinolysis (i.e., PMI-1), activated platelets and clotting

(i.e., factor VII, thrombin generation, F1 + 2)

Surface of residual thrombus


(i.e., recurrence)

(C. Pneumoniae, CMV, H. Pylori)



(i.e., platelets, thrombin)


Hypercoagulable states, in turn, have been traditionally associated with venous thrombosis. Consequently, attention has been paid to alterations of the hemostatic balance. Although this is a systemic variable, focality is favored due to the contribution of decreased blood flow, as confirmed by the preferential development of venous thrombi at the level of valves, an area of stasis where low-velocity flow is moderately turbulent.

In conclusion, hemostasia intervenes in distinct critical steps of both the arterial and venous forms of CVD. The particulars, however, differ in each case, as confirmed by the different array of risk factors for CHD and VTED. The participation of the vascular wall is pivotal in explaining the focality of these processes. Within the vascular wall, the role of the endothelium is critical given its involvement in the origin of atherosclerosis and its influence on the development of VTED (for review see Cano and Van Baal 2001; Cano 2003).


The Crucial Role of the Endothelium

The vascular wall is an organ composed of an endothelium, smooth muscle, and fibroblasts. The endothelium has a privileged position to act as both a sensor and an effector. The endothelium governs remodeling by releasing growth factors and vasoactive substances that regulate cellular growth and apoptosis. The key role of endothelium in the plasticity of the vascular wall helps to better understand the modern hypotheses that root the initiation and development of atherosclerosis in endothelial dysfunction (Ross 1999). The rupture of the coordinated equilibrium of checks and balances that is at the base of endothelial homeostasis is followed by a well-described sequence of events starting with the increase of adhesiveness of the endothelium to leukocytes or platelets and leading to an atherosclerotic plaque (Ross 1999) (Fig. 1). The progression of the plaque follows several steps represented by lesions I to IV (Fuster et al. 1992a,b).

Fig. 9.1. A dysfunctional or injured endothelium is at the basis for initiation of and progression to atherosclerosis. Several mechanisms, such as adhesion molecules or liberation of von Willebrand factor (vWf, upper panel), determine a series of phenomena, including platelet activation and aggregation. This participation of platelets involves the implication of molecules like glycoprotein IIb/IIIa, fibrinogen, and von Willebrand factor. The endothelium also acts as a source of signals that regulate local functions, including VSMCs (lower panel). A list of the most relevant messengers produced by a functional and a dysfunctonal endothelium is presented in the lower panel

A very innovative area of research has focused on the determinants of plaque stability. An important role seems to be played by enzymes involved in the degradation of the extracellular matrix. The rupture of unstable plaques induces platelet activation, too. Acute thrombus formation under these conditions seems fundamental to the onset of acute ischemic events.

A key concept inferred from the ideas discussed above is the difference between the development of conditions that favor the clinical eruption of any form of CVD (i.e., atherosclerosis) and the proper occurrence of the clinical event, since the inductors do not necessarily have to be the same. Furthermore, the possibility exists that a concrete factor may be protective at several stages of the silent form of the disease, but once it is sufficiently advanced, it may act as a trigger. This distinction is pivotal when considering the role of hormones, which have been shown to differentially regulate atherosclerosis and proper clinical events.


Estrogen Agonism and CVD

Some crucial steps in the biology of CVD have demonstrated sensitivity to estrogen agonists. Some of these actions have shown to be mediated by the classical pathway of estrogen receptors (ERs), though in other cases the involved mechanisms seem more complex and require the consideration of alternative options (Mendelsohn 2002). The available evidence concentrates on actions on lipids or on direct actions on the vascular wall.



There is plenty of information concerning lipid changes as a result of estrogen agonistic effects. Most of the data come from studies with either synthetic or natural estrogens.

A protective lipid profile, with reduction of total cholesterol and LDL and a modest increase in high-density lipoprotein (HDL), has been associated with oral estrogen therapy (Writing Group for the PEPI Trial 1995). This effect, however, has been considered negligible when compared with the benefits traditionally ascribed to estrogens (Marsh et al. 1999).

More interest has been generated by the potential effects of estrogens as modulators of LDL oxidation, a mechanism considered to be the authentic mediator of the detrimental action of LDL particles in atherosclerosis. Oxidized LDL becomes trapped in an artery and is then internalized by macrophages (Steinberg 1997; Navab et al. 1996; Morel et al. 1983; Griendling and Alexander 1997). This internalization leads to the formation of lipid peroxides resulting in the formation of foam cells. Additionally, oxidized LDL is an agent that by itself promotes vasoconstriction and platelet activation (Kugiyama et al. 1990; Chin et al. 1992; Chen et al. 1996).

Estrogens have been shown to limit LDL susceptibility to oxidation, although this action is under discussion at present. Only supraphysiological doses have demonstrated this effect in the laboratory (Hermenegildo et al. 2001; Santanam et al. 1998). Some indirect evidence favoring protection, such as the reduction of antibodies to oxidized LDL, has been proposed (Hoogerbrugge et al. 1998), but, again, there is no general consensus on the subject (Uint et al. 2003; Heikkinen et al. 1998). More recent research has found that estrogens reduce the production of F2a-isoprostanes, a product of a nonenzymatic, free radical catalyzed peroxidation of arachidonic acid (Liu et al. 1998) that has been recognized as a stable, good biomarker of in vivo oxidative stress (de Zwart et al. 1999; Pratico 1999). Moreover, increased Fisoprostane levels have been found in human atherosclerotic lesions (Oguogho et al. 2001) and are being considered as a reliable biomarker of both atherosclerosis (Gross et al. 2005) and coronary events (Vassalle et al. 2003) (Fig. 9.2).


Vascular Wall

The vascular wall is a target for sexual hormones. In the particular case of estrogens, specific receptors have been found in both endothelium and vascular smooth muscle cells (VSMC) (Venkov et al. 1996; Karas et al. 1994). The trophic effects ofestrogens on the endothelium have been advocated as crucial against initiation and promotion ofatherosclerosis. Thus, cellular and animal models, as well as clinical observation with doppler techniques, confirm that estrogens promote vasodilation. This effect is maintained for years in menopausal women subjected to HT (Jokela et al. 2003). Nitric oxide (NO) and prostacyclin (PGI), two main locally produced antiaggregant and vasodilatory mediators, are the principal agents in this myorelaxant effect of estrogens (Couzin 2004). In agreement with current concepts, their effects have been demonstrated as protective against atherosclerosis in animal models (Perrault et al. 2003; Niebauer et al. 2003; Todaka et al. 1999). Together with the protection associated with these mediators, the inhibition of TNF-alpha-induced endothelial cell apoptosis in a dose-dependent manner has been an additional beneficial effect linked with estrogens (Spyridopoulos et al. 1997).

Proliferation and migration ofVSMC follows endothelial dysfunction. Limitation of this activity in VSMC has been understood to be protective against atherosclerosis. The effect ofestrogens on VSMC proliferation is controversial. Some studies have reported a reduced proliferative capacity by estrogens in a dose-dependent manner (Bhalla et al. 1997; Moraghan et al. 1996; Espinosa etal. 1996; Akishita et al. 1997) and through activation of ER (Vargas et al. 1996). In contrast, other investigators have found induction of VSMC proliferation with estrogens (Ricciardelli et al. 1994; Song et al. 1998).

Experiments in monkeys have shown that estrogens alone, or in association with progestogens, protect against diet-induced atherosclerosis (Clarkson 1994). There has been some discussion on whether or not this is the case in humans, although HT was unable to have a significant effect on the progression of the disease in women with established atherosclerosis (Hodis et al. 2003).


SERMs as an Alternative to Estrogens in CVD

The expectations created for estrogens faded as a result of the publication of randomized clinical studies, which failed to show any protection against any of the CVD forms in postmenopausal women receiving hormones (Hulley et al. 1998; Rossouw et al. 2002). The clear opposition between these trials and most ofthe experimental and previous clinical studies has raised much discussion in the literature (Speroff 2002). Despite the many criticisms against distinct details of the discrepant studies, there is consensus on the appreciable regulatory effects ofthe hormone on the vascular wall. This conception, together with the significant advances experienced by the knowledge on the molecular details of estrogen action, has created a great opportunity for investigating alternative agonists with a potentially better profile than estrogens themselves.

In one a priori analysis the versatility of ER modulation offers a wide array of options. These include the selective activation of either the ERa or the ERβ isoform, or the use of compounds sufficiently similar to estrogens so as to bind to the ER, yet different enough to generate a ligand-receptor complex with a 3D conformation capable of activating cell functions with a profile distinct to estrogens (Fig. 9.3). The interesting observation that ERβ can interact with ERa, together with the varied distribution of each ER isoform in different tissues, has raised attractive possibilities associated with selective binding to one or another isoform. Despite the recent availability of compounds with selective agonism for either ERa or ERβ (Harrington et al. 2003; Muthyala et al. 2003; Ghosh et al. 2003), there is no clear proof to date associating the selective action of any of the available SERMs in the vascular system with preferential binding to one of the two ER isoforms. Consequently, the most consistent data on cardiovascular effects of SERMs have been obtained in studies with compounds that have been approved for use in patients, particularly tamoxifen, raloxifene, and toremifene.

Another important point to keep in mind when reviewing the cardiovascular effects of SERMs is that, in the absence of clinical studies of consistency comparable to estrogens, most of the available evidence has been obtained in experimental models. The work has concentrated on the selective areas of vascular physiology that have shown susceptibility to ER activation and, therefore, has followed steps that often overlap with those taken in research with estrogens.

Fig. 9.3. Several mechanisms underlie the functional versatility of the ER. The different distributions of the alpha and beta isotypes of ER conditions a first step that warrants distinct functional profiles depending on the higher or lower affinity of the ligand for one or another isotype (upperpanel). Then, different ligands generate distinct 3D conformations in the ligand-receptor complex that condition different interaction profiles with the promoters of target genes (lower panel)


Actions of SERMs


Arterial Disease

Most of the forms of arterial disease result from atherosclerosis and its complications. The evidence against protection refers not only to CHD but also against stroke (Hulley et al. 1998; Rossouw et al. 2002; Bath and Gray 2005).

Lipids and Lipid Peroxidation

Changes in the lipid profile, which exhibits small differences from that associated with oral estrogens, have been described for tamoxifen, toremifene, and raloxifene. One common finding has been the decrease in the circulating concentration of cholesterol and LDL cholesterol, an effect with a magnitude that seems directly related to pretreatment levels (Walsh et al. 1998; Delmas et al. 1997; Saarto et al. 1996; Decensi et al. 2003; Joensuu et al. 2000; Herrington et al. 2000). Contrary to the increase in triglycerides described for estrogens, a more beneficial neutral response appears associated with SERMs. Slight increases in triglycerides, however, have been found in women treated with raloxifene (Mosca et al. 2001b; Reid et al. 2004), and cases of acute triglyceridemia have been associated with tamoxifen (Hozumi et al. 1997; Kanel et al. 1997). Only toremifene has achieved increases in the levels of high-density lipoprotein (HDL) (Saarto et al. 1996).

More refined analyses have focused on changes in the ratio of serum concentration of apolipoprotein B, the common constituent in all lipoproteins comprising non-HDL cholesterol, to apoliprotein A, the apolipoprotein associated with HDL. Raloxifene was equivalent to HT in lowering the apolipopro- tein B/apolipoprotein A ratio in one study (Anderson et al. 2001).

Because of the similarity, it is difficult to conclude whether the lipid changes induced by SERMs offer any advantage over the profile determined by HT. Triglyceride levels have been proposed as an independent risk factor for CVD in postmenopausal women (Miller 1998). Further, there are some indications that increases in triglycerides may favor the reduction in the size of LDL particles. Smaller LDL particles are more susceptible to oxidation and have been associated with a higher risk potential (Austin et al. 1988), but whether this observation confers any clinical prejudice to hypertriglyceridemia has not been proven at present.

There is fragmentary information concerning the behavior of some more recent SERMs. Whereas ospemifene showed a neutral effect (Ylikorkala et al.

Fig. 9.4. One pure antiestrogen, ICI 182780, increased the resistance of LDL particles to oxidation. Isolated LDL particles were subjected to oxidation by copper, and the lag time to oxidation, as measured by changes in optical density, increased as a function of the concentration of ICI 182780 (upper panel). The increase in the lag time (min) determined by the different concentrations of ICI 182780 is shown in the lower panel 2003), HMR 3339, a newly designed molecule that binds to human recombinant ER and shows selective agonistic and antagonistic activity in vitro and in vivo, rapidly decreased cholesterol and LDL in a dose-dependent manner (Vogelvang et al. 2004). It seems, therefore, that the decrease in non-HDL cholesterol is a hepatic effect quite accessible to compounds that, despite differences in chemical structure, are capable of exerting some type of SERM activity.

The relevance attributed to oxidized lipids, and particularly oxidized LDL, in atherogenesis has precipitated interest in the ability of SERMs to this regard. Ex vivo experiments have confirmed that both tamoxifen and raloxifene exert some protection against the oxidation of LDL particles (Arteaga et al. 2003; Zuckerman and Bryan 1996) and that, interestingly, raloxifene is a more powerful antioxidant than tamoxifen or estradiol. It seems that this antioxidant effect is not mediated by the activation of the ER since pure antiestrogens like ICI 182780 and other SERMs like EM 652 have proven to have similar protective effects on LDL (Hermenegildo et al. 2002) (Fig. 9.4).

Little evidence exists concerning alternative actions on oxidative stress, such as modulation of the circulating levels of isoprostanes or myeloperoxidase. Some interference with the actions of myeloperoxidase, however, was found in one study (Zuckerman and Bryan 1996). Antioxidant properties have been described for other types of SERMs, thus confirming the wide extension of this potential in the different families of these compounds (Baumer et al. 2001).

Direct Actions on Vascular Wall


The idea that the endothelium is a target organ for estrogens derives from more than just the identification of both isoforms of ER in this tissue (Mendelsohn 2000). There is ample evidence showing rapid responses that are compatible with mechanisms distinct from the classical pathway for estrogen action. A species of membrane ER that determines a rapid activation of nitric oxide synthase (NOS) has been described recently in immortalized human endothelial cells (Li et al. 2003). Both genomic and nongenomic actions have been proposed to explain the estrogenic regulation of endothelial functions.

Among the local mediators directly produced by endothelium, NO and PGI emerge as two principal regulators of vascular tone and platelet aggregation. Both are sensitive to estrogenic stimuli, and, as mentioned in a previous section, their role is crucial in atherogenesis. How their production is modulated by SERMs is, consequently, an important test of vascular protection.

Much of the data concerning the effects of SERMs on these endothelial mediators refer to raloxifene, given its wide therapeutical use in women free of malignancies. Raloxifene has demonstrated the induction of NOS and NO production in endothelial cells in culture. Furthermore, this effect occurs in seconds and involves nongenomic mechanisms where NOS is phosphorylated in a process implicating Akt and extracellular signal-regulated protein kinase with the participation of ER alpha and reduction of oxidative stress (Simoncini and Genazzani 2000; Wassmann et al. 2002). In agreement with this agonistic action, experiments on the same cellular model have confirmed an activation of cyclooxygenase-1 and -2 at both the protein and the gene level, leading to increased prostacyclin production (Oviedo et al. 2004, 2005). Selective blockade of both isoforms of ER has confirmed the involvement of both ERα and ERβ as well as the likely participation of a mechanism distinct to the classical ER-dependent pathway.

Experiments with isolated vessels have confirmed the enhancing effect of raloxifene on endothelial NOS (Rahimian et al. 2002) with a similar behavior for tamoxifen (Hutchison et al. 2001).

The data with cells and isolated organs have been corroborated in animal models. An increase in endothelial NOS expression and activity was observed in spontaneously hypertensive rats (Wassmann et al. 2002), whereas in ovariectomized ewes the vasodilating effect of raloxifene surpassed that of estrogens (Gaynor et al. 2000). Endothelium-dependent vasodilation was observed for rabbit coronary arteries in vitro, an effect that agrees with some vascular relaxing properties described for toremifene, tamoxifen, idoxifene, and EM 652 in rat vessels (Gonzalez-Perez and Crespo 2003; Thorin et al. 2003; Figtree et al. 2000; Christopher et al. 2002; Tatchum-Talom et al. 2003).

Mixed evidence, however, has been described in women. Raloxifene improved flow-mediated, endothelium-dependent vasodilation in postmenopausal women (Sarrel et al. 2003) to an extent similar to that of HT (Colacurci et al. 2003; Saitta et al. 2001). Other investigators, however, have been unable to detect any effect of raloxifene (Ceresini et al. 2003; Griffiths et al. 2003). Flow-mediated vasodilation has been described for droloxifene (Herrington et al. 2000), while a neutral effect on vascular reactivity has been described for ospemifene, a more recent SERM (Ylikorkala et al. 2003).

One early sign of endothelial dysfunction consists of the expression of cell adhesion molecules at the endothelial surface. These molecules facilitate leukocyte and platelet binding. Further, endothelial permeability is dependent on interendothelial junctions, where the participation of cadherin, a transmembrane, endothelium-specific glycoprotein, exerts an important level of control (Bobryshev et al. 1999; Fulimoto et al. 1998). Once expressed, adhesion molecules may be shed from the endothelial surface. An increase in adhesion molecules in plasma, therefore, is understood as a sign of endothelial dysfunction and permeability. Furthermore, raised levels of cell adhesion molecules in blood have been associated with increased risk for CHD (Blankenberg et al. 2001; Hwang et al. 1997). A well-established effect of estrogens has been the reduction of the circulating concentration of cell adhesion molecules (Koh et al. 1997), an effect paralleled by raloxifene (Blum et al. 2000; Sbarouni et al. 2003; Colacurci et al. 2003). Different actions have been found for other SERMs in the sparse literature available. Tamoxifen had a neutral effect in one study (Simoncini et al. 1999), whereas in another study droloxifene had a mixed effect, with a decrease in E-selectin and an increase in vascular cell-adhesion molecule-1 (VCAM-1) (Herrington et al. 2001).

Finally, a new area of research has concentrated on monocyte chemotactic protein-1 (MCP-1), a 76-amino acid peptide that is one of the best-studied members of the C-C chemokine subfamily. Recent human and animal studies indicate that the recruitment of macrophages to the arterial lesion is predom inantly mediated by MCP-1. There are preliminary data showing that both tamoxifen and raloxifene parallel estradiol in reducing the expression of MCP- 1 in a model of endothelial cells in culture (Seli et al. 2002).


Indirect evidence suggests that the blockade of VSMC proliferation is associated with ER agonism (Lavigne et al. 1999). The data obtained with SERMs are still sparse and mainly restricted to raloxifene. In experiments in vitro, raloxifene exhibited an effect similar to estrogens in inducing arrest and apoptosis in VSMC (Takahashi et al. 2003; Mori-Abe et al. 2003). Consistent with this observation, raloxifene was equivalent to estradiol in limiting intimal thickening in a model of ovariectomized senile ewes (Selzman et al. 2002). Some evidence favors a similar protective effect for other SERMs, like idoxifene (Yue et al. 2000) and tamoxifen (Dubey et al. 1999; Somjen et al. 1998; Grainger et al. 1993).

Atherosclerotic Plaque

The biological effects that have been described above, i.e., reduction of LDL and its oxidation, the protection of endothelial function, and the limitation of VSMC proliferation, globally suggest a protective effect against atherosclerosis. This hypothesis has been assayed with the use of distinct animal models with diet-induced atherosclerosis. Some experiments have been carried out in genetically modified mice that have been subjected to targeted inactivation of the apolipoprotein E (apo E) and LDL receptor (LDLR) genes. These animals respond to moderate amounts of dietary cholesterol with severe hypercholesterolemia and develop lipid-rich vascular lesions resembling human atherosclerotic plaques. An atheroprotective effect has been confirmed for estrogens in rabbits (Haines et al. 1999; Haarbo et al. 1991; Bjarnason et al. 1997, 2001; Hough and Zilversmit 1986) and monkeys (Adams et al. 1990; Wagner et al. 1991) subjected to an atherogenic diet. Experiments with LDLR- and apoE-null mice further confirmed that the extent of atheroprotection by estradiol was greater than could be explained solely by the change in lipid levels (Hodgin et al. 2001; Tangirala et al. 1995; Elhage et al. 1997; Marsh et al. 1999).

The data obtained with SERMs are more mixed. Tamoxifen attenuated atheroma development in apoE-null mice, an effect that correlated with changes in the lipoprotein profile and with elevated levels of transforming growth factor-β (Reckless et al. 1997). The accumulation of cholesterol in atherosclerotic lesions (Bjarnason et al. 1997) in the aorta was limited by

raloxifene in a model of cholesterol-fed rabbits. Subsequent experiments with the same model confirmed that raloxifene reduced atherosclerosis (Bjarnason et al. 2000), an effect similar to that of estrogens in another study where progression of advanced atherosclerosis was limited (Bjarnason et al. 2001) (Fig. 9.5). In a primate model, however, in which a tête-a-tête comparison between estrogens and raloxifene was carried out, only estrogens, but not raloxifene, effectively limited atherosclerosis (Clarkson et al. 1998). Protection against VSMC proliferation in culture as well as in experimental models of atherogenesis in rats has been described for idoxifene (Yue et al. 2000). A more active reendothelialization was observed in treated animals in the same study.

Only fragmentary information exists in the human. In a study on 27 postmenopausal women with breast cancer, tamoxifen slightly slowed the progression of atherosclerosis as assessed by changes in carotid intima-media thickness (Stamatelopoulos et al. 2004).

Fig. 9.5. Protection by SERMs against atherosclerosis has been researched in animals. In a model of ovariectomized rabbits, raloxifene reduced the cholesterol content in the inner part of the aorta more than placebo did (upper panel). This effect was more intense in animals treated with estradiol (Bjarnason et al. 1997). In contrast, in a different model of oophorectomized monkeys (lower panel), estradiol, and not raloxifene at two different dosages, significantly decreased the size of atherosclerotic plaques (Clarkson et al. 1998)

Inflammatory Markers and Mediators

The results of both the WHI and HERS studies have contributed decisively to clarifying the difference between atherogenesis itself and the rupture of one atheromatous plaque as the concrete phenomenon leading to an occlusive vascular event. Although necessarily interrelated, the slow progression of a stable plaque, with its consequent reduction of the arterial lumen, may have its ischemic effects limited by the adaptive response including the concurrent development of collateral circulation (Fuster et al. 1992a,b). The concatenation of acute thrombosis as a result of either plaque disruption or severe erosion of the endothelial surface is, however, at the base of most acute coronary syndromes. This concept defines the support of the most widely accepted hypothesis on the action of hormones. As a result of this conception, much interest has arisen in the study of inflammatory mechanisms that underlie disruption of the cap of a lipid-rich plaque, the characteristic form of so-called unstable plaques. It has been shown that estrogens may modify local inflammatory processes and promote the expression and activity of metalloproteinases, a group of enzymes active in the digestion of the matrix (Zanger et al. 2000).

In this new scenario much attention is being paid to the investigation of a series of markers of inflammation as reliable indicators of coronary risk. Their value is stressed by the observation that up to one third of events occurs in subjects without traditional risk factors. The C-reactive protein (CRP) seems to provide the strongest risk prediction for CHD in women (Albert 2000; Ridker 2001), although homocysteine, interleukin-6 (IL-6), and lipoprotein (a) [Lp(a)], among others, have each been independently associated with increased risk for CHD in women (for a review see Davison and Davis 2003; Rader 2000).

As for lipids, the effects of SERMs do not overlap exactly those of HT. Oral estrogens increase the circulating levels of CRP (Writing Group for the PEPI Trial 1995), while this is not the case for raloxifene (Walsh et al. 2000). A better profile was observed for droloxifene as well as for tamoxifen, which achieved a diminution of CRP (Herrington et al. 2001; Cushman et al. 2001).

Slight, yet similar, range decreases were observed for oral estrogens and raloxifene when studied for changes in homocysteine (Walsh et al. 2000; Smolders et al. 2002; Mijatovic et al. 1998; De Leo et al. 2001), a molecule that may have damaging effects on endothelium. A reduction was found for Lp(a), too, although in this case the decrease achieved for estrogens was of a higher magnitude in one study (- 19% vs. - 7%) (Walsh et al. 2001). Droloxifene, however, was more efficient than estrogens in reducing Lp(a) levels (Herrington et al.


IL-6 participates in both atherogenesis and inflammatory processes. In one interesting mouse model that was double deficient at the apoE and IL-6 loci, animals displayed similar hypercholesterolemia compared to apoE-null mice, but disclosed larger and more calcified lesions at 1 year of age (Klinge 2001). Thus, IL-6 appears to be involved at the fibrous plaque stage of the atherosclerotic process. Moreover, IL-6 is a key factor in the generation of the hepatic acute-phase response and so increases the levels of CRP, fibrinogen, platelet number and activity, and blood viscosity. Only raloxifene has been tested for IL-6, which did not change in one study (Walsh et al. 2001) and decreased by 35% in another study after 24 months of treatment (Gianni et al. 2004). Tumor necrosis factor a (TNFa) is another cytokine associated with cardiovascular risk in epidemiological studies (Ridker et al. 2000). Similar decreases for TNFa have been found in a study comparing HT and raloxifene (Walsh et al. 2001).

Table 9.3. Effects of SERMs on inflammatory markers in postmenopausal women

In conclusion, SERMs exhibit changes in inflammatory markers that do not match those found with oral HT. Some variability exists within HT itself, depending on the compound (estrogens or tibolone) and on the administration route (oral vs. transdermal). There is sufficient background to hold the value of inflammatory markers as strong indicators of coronary risk, but whether interventions modifying their circulating levels have an influence in risk is still uncertain. A summary of the effects of SERMs on inflammatory markers may be found in Table 9.3.


The apparent protection conferred to the endothelium by estrogens in healthy women operates in favor of platelet stabilization. This interpretation agrees with studies on platelet aggregation that is diminished in response to different stimulants while under exposure to estrogens (Bar et al. 1993, 2000; Nakano et al. 1998; Chen et al. 1998). Nonetheless, in women with advanced atherosclerosis and unstable plaques the picture may be different. Furthermore, little is known about the mechanisms involved in platelet activation, and the sparse evidence is not always favorable to estrogens (Garci'a-Marti'nez et al. 2004). Whether a different profile is imposed by SERMs is not totally clear. Recent work has demonstrated that raloxifene shares with estradiol some protective effects on platelet aggregation induced by ovariectomy (Jayachandran et al.

2005). In a flow chamber model tamoxifen has shown no effect on platelet aggregation (Miller et al. 1994), an effect that agrees with experiments on platelets subjected to different endocrine environments since, unlike hormonal contraceptives, tamoxifen reduced intracellular calcium and release (Miller et al. 1995).

Additionally, attention has been focused on some factors that, operating in the hemostatic balance, have been attributed the role of risk markers of clinical events. Thus, increased plasma concentration of factor VII, fibrinogen, plasminogen activator inhibitor type 1 (PAI-1), and the already mentioned Lp(a) have been associated with the occurrence of CHD. Much work has been done on the modulation of these factors by HT (for a review see Cano and Van Baal 2001), and both similarities and differences have been found in the sparse literature on SERM action. Raloxifene and droloxifene decrease fibrinogen more actively than does HT (Walsh et al. 1998; Herrington et al. 2000). In contrast, the effective reduction demonstrated for PAI-1 with oral HT was not confirmed for raloxifene or droloxifene (Walsh et al. 1998; de Valk-de Roo et al. 1999; Herrington et al. 2000).

Clinical Data

There are no randomized clinical trials on the efficacy of SERMs in either the primary or the secondary prevention of CHD. The Raloxifene Use for the Heart ;RUTH) study is a trial specifically designed to clarify the effect of raloxifene on the risk of CHD. The study had included 10,101 women from 26 countries it the closure of the inclusion period, August 2000 (Mosca et al. 2001a). Results rom the trial remain to be reported.

Indirect evidence favoring protection has been obtained from a post hoc analysis of the data from the Multiple Outcomes of Raloxifene Evaluation (MORE) study in the subgroup of women who were at increased risk. Using the same scoring system as in the RUTH study to stratify women, a total of 1035 women were assessed as being at significant coronary risk (Barrett- Connor et al. 2002). When women within the group that had been randomized to raloxifene were separated from those randomized to placebo it came up that treatment was associated with protection against new clinical events, and that the higher the score, the greater the protection (Fig. 9.6).

Fig. 9.6. Relative risk (±95% confidence intervals) for any cardiovascular event in the group treated with raloxifene or placebo. The information was obtained from the subgroup of women at increased cardiovascular risk in the MORE study. The overall data seem to favor raloxifene, but this effect is clearer when women were grouped according to their risk as assessed by the previously defined severity score (from Barrett-Connor et al. 2002)

The effects of tamoxifen in women with and without CHD have been ana­lyzed in the National Surgical Adjuvant Breast and Bowel Project Breast Can­cer Prevention Trial (BCPT). This randomized, placebo-controlled study in­cluded 13,388 women at increased risk for breast cancer. The conclusions of the trial are somewhat limited by the fact that it was designed to inves­tigate the effect of tamoxifen as a chemopreventive for breast cancer, and not its effect on CVD risk. There was no indication that tamoxifen would modify the risk of CHD in women with or without heart disease (Reis et al. 2001).



A consistent observation linked with estrogen agonism has been the increased risk of VTED. Both hormonal contraceptives and HT determine increased risk oscillating from 2- to 11-fold for contraceptives (Hannaford and Owen- Smith 1998) and from 2- to 4-fold for HT (Daly et al. 1996; Jick et al. 1996; Grodstein et al. 1996; Pérez-Gutthan et al. 1997; Varas-Lorenzo et al. 1998). The risk has been associated with estrogens, but particularly in the case of some third-generation molecules used in contraception, also with the progestogenic component (Vandenbroucke et al. 2001). Interestingly, and despite intensive research, there is not a sufficiently clear understanding of the mechanisms set in motion by hormones to promote risk (Cano and Van Baal 2001). Venous thrombogenesis seems influenced by both hypercoagulable states and flow disturbances, including the independent or collaborative effects of decreased flow and local turbulence (Cano 2003). Much of the research has focused on the inhibitory action that some studies have detected for hormones on the natural anticoagulant system. It is intriguing, however, that increased risk associated with exogenous hormones is not reproduced by endogenous hormones. As mentioned above, age and not gender determines the increase in risk in the general population. Some data find an even slightly higher risk for men during aging (Silverstein et al. 1998).

It is remarkable that most of the data collected from the available SERMs are unanimous in reproducing an estrogen agonistic profile in venous throm- bogenesis. The vast clinical experience acquired with tamoxifen confirms an augmented risk for both deep venous thrombosis and pulmonary embolism. This increase, however, did not presuppose increased mortality in the overview of randomized trials of adjuvant tamoxifen for early breast cancer, where the one extra death per 5000 woman-years of tamoxifen attributed to pulmonary embolus was not statistically significant (Early Breast Cancer Trialists’ Collaborative Group 1998).

The main source of data for raloxifene derives from the MORE study. A twofold increased risk for VTED was observed through 4 years of followup (Delmas et al. 2002), and, as for HT and tamoxifen, an accumulation of events occurred during the first year.

There is discussion on the adequacy of tests to identify the hypercoagula- ble states underlying susceptibility to VTED. The complexity of factors and interactions involved in the hemostatic equilibrium has favored the use of functional tests. Among the several options available the measurement of fragments 1 + 2 (F1 + 2), the amino terminus fragment split during the activation of prothrombin has been widely considered the test of choice. The sparse information available for SERMs, however, is unclear. Raloxifene did not modifyF1 + 2 fragments in one study where HT was also neutral (Walsh et al. 1998). Other investigators, however, detected slight increases in F1 + 2 fragments for HT in another direct comparison with raloxifene (de Valk-de Roo et al. 1999).


Conclusion and Outlook for the Future

The different profiles of the diseases integrated within CVD make their sensitivity to the modulation of ER or, in a more general view encompassing other alternative agonistic pathways, of estrogen action rather variable. There is a clear gender influence on CHD only, but, and of interest, the administration of hormones affects the risk for other forms of CVD, like VTED or stroke. This reality, together with the vast amount of experimental data confirming the action of estrogens on several mechanisms crucial in the pathogenesis of each form of CVD, has reinforced the concept of the important regulatory potential of estrogens. Advances in the knowledge of estrogen action have opened up the field of SERMs, which in one a priori analysis should accomplish a peculiar profile of actions. The data obtained to date confirm this assumption.

The greatest amount of information has been compiled for CHD. The most widely used SERMs, like tamoxifen and raloxifene, seem to behave acceptably concerning the mechanisms underlying the disruption of atherosclerotic plaques. This maybe an advantage over estrogens, and some preliminary clinical data seem to favor this interpretation. In contrast, it seems estrogens might perform better in protecting against atherosclerosis development. There is very little information on whether SERMs may offer advantages against arterial stroke, although the increase associated with estrogens in recent randomized, placebo-controlled clinical trials have not been detected for SERMs. Although it only offered data on mortality and did not clearly separate the distinct CVD forms, the important overview of randomized trials of adjuvant tamoxifen could not find increased mortality for the aggregate of all cardiac or vascular deaths (Early Breast Cancer Trialists’ Collaborative Group 1998).

Venous thrombosis defines a field where there is a strong parallel performance of estrogens and of the SERMs presently developed. This adds to the still mysterious mechanisms underlying the increase in risk that has been found. There is plenty of evidence in favor of an antagonism of hormones on the anticoagulant pathway of hemostatic equilibrium, but very poor data have been obtained with functional tests of coagulation. The dearth of information on the mechanisms by which estrogens/SERMs interfere with anticoagulation further impairs the finding of successful research options.

In conclusion, we are at a very preliminary step on what is probably a long but promising path. The modulation of estrogen action seems a powerful mechanism in the control of CVD risk. Additional advances in the knowledge of estrogen action as well as in the improvement in the design process of new SERMs should offer substantial progress in this area. The concomitant acquisition of clinical data, as is expected from the RUTH study, will consolidate research developments.


1. Adams MR, Kaplan JR, Manuck SB, Koritnik DR, Parks JS, Wolfe MS, Clarkson TB (1990) Inhibition of coronary artery atherosclerosis by 17-beta estradiol in ovariectomized monkeys. Lack of an effect of added progesterone. Arteriosclerosis 10:10511057

2. AkishitaM , OuchiY, Miyoshi H , Kozaki K , InoueS , IshikawaM , Eto M , Toba K , OrimoH (1997) Estrogen inhibits cuff-induced intimal thickening of rat femoral artery: effects on migration and proliferation of vascular smooth muscle cells. Atherosclerosis 130:1-10

3. Albert MA (2000) The role of C-reactive protein in cardiovascular disease risk. Curr Cardiol Rep 2:274-279

4. Anderson PW, Cox DA, Sashegyi A, Paul S, Silfen SL, Walsh BW (2001) Effects of raloxifene and hormone replacement therapy on markers of serum atherogenicity in healthy postmenopausal women. Maturitas 39:71-77

5. Anderson GL, Limacher M, Assaf AR, Bassford T, Beresford SA, Black H, Bonds D, Brunner R, Brzyski R, Caan B, Chlebowski R, Curb D, Gass M, Hays J, Heiss G, Hendrix S, Howard BV, Hsia J, Hubbell A, Jackson R, Johnson KC, Judd H, Kotchen JM, Kuller L, LaCroix AZ, Lane D, Langer RD, Lasser N, Lewis CE, Manson J, Margolis K, Ockene J, O’Sullivan MJ, Phillips L, Prentice RL, Ritenbaugh C, Robbins J, Rossouw JE, Sarto G, Stefanick ML, Van Horn L, Wactawski-Wende J, Wallace R, Wassertheil- Smoller S, Women’s Health Initiative Steering Committee (2004) Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women’s Health Initiative randomized controlled trial. J Am Med Assoc 291:1701-1712

6. Arteaga E, Villaseca P, Bianchi M, Rojas A, Marshall G (2003) Raloxifene is a better antioxidant of low-density lipoprotein than estradiol or tamoxifen in postmenopausal women in vitro. Menopause 10:142-146

7. Austin MA, Breslow JL, Hennekens CH, Buring JE, Willett WC, Krauss RM (1988) Low-density lipoprotein subclass patterns and risk of myocardial infarction. J Am Med Assoc 260:1917-1921

8. Badimon JJ, Zaman A, Helft G, Fayad Z, Fuster V (1999) Acute coronary syndromes: pathophysiology and preventive priorities. Thromb Haemost 82:997-1004

9. Bar J, Tepper R, Fuchs J, Pardo J, Goldberger S, Ovadia J (1993) The effect of estrogen replacement therapy on platelet aggregation and adenosine triphosphate release in postmenopausal women. Obstet Gynecol 81:261-264

10. Bar J, Lahav J, Hod M, Ben-Rafael Z, Weinberger I, Brosens J (2000) Regulation of platelet aggregation and adenosine triphosphate release in vitro by 17beta-estradiol and medroxyprogesterone acetate in postmenopausal women. Thromb Haemost 84:695-700

11. Barrett-Connor E, Grady D, Sashegyi A, Anderson PW, Cox DA, Hoszowski K, Rauta- harju P, Harper KD, MORE Investigators (Multiple Outcomes of Raloxifene Evaluation) (2002) Raloxifene and cardiovascular events in osteoporotic postmenopausal women: four-year results from the MORE (Multiple Outcomes of Raloxifene Evaluation) randomized trial. J Am Med Assoc 287:847-857

12. Bath PMW, Gray LJ (2005) Association between hormone replacement therapy and subsequent stroke: a meta-analysis. Br Med J DOI:10.1136/BMJ.38331.655347.8F

13. Baumer AT, Wassmann S, Ahlbory K, Strehlow K, Muller C, Sauer H, Bohm M, Nick- enig G (2001) Reduction of oxidative stress and AT1 receptor expression by the selective oestrogen receptor modulator idoxifene. Br J Pharmacol 134:579-584

14. Bhalla RC, Toth KF, Bhatty RA, Thompson LP, Sharma RV (1997) Estrogen reduces proliferation and agonist-induced calcium increase in coronary artery smooth muscle cells. Am J Physiol 272:H1996-2003

15. Bjarnason NH, Haarbo J, Byrjalsen I, Kauffman RF, Christiansen C (1997) Raloxifene inhibits aortic accumulation of cholesterol in ovariectomized, cholesterol-fed rabbits. Circulation 96:1964-1969

16. Bjarnason NH, Haarbo J, Byrjalsen I, Kauffman RF, Knadler MP, Christiansen C (2000) Raloxifene reduces atherosclerosis: studies of optimized raloxifene doses in ovariec- tomized, cholesterol-fed rabbits. Clin Endocrinol 52:225-233

17. Bjarnason NH, Haarbo J, Byrjalsen I, Alexandersen P, Kauffman RF, Christiansen C

(2001) Raloxifene and estrogen reduces progression of advanced atherosclerosis - a study in ovariectomized, cholesterol-fed rabbits. Atherosclerosis 154:97-102

18. Blankenberg S, Rupprecht HJ, Bickel C, Peetz D, Hafner G, Tiret L, Meyer J (2001) Circulating cell adhesion molecules and death in patients with coronary artery disease. Circulation 104:1336-1342

19. Blum A, Schenke WH, Hathaway L, Mincemoyer R, Csako G, Waclawiw MA, Cannon RO III (2000) Effects of estrogen and the selective estrogen receptor modulator raloxifene on markers of inflammation in postmenopausal women. Am J Cardiol 86: 892-895

20. Bobryshev YV, Cherian SM, Inder SJ, Lord RSA (1999) Neovascular expression of VE- cadherin in human atherosclerotic arteries in its relation to intimal inflammation. Cardiovasc Res 43:1003-1017

21. British Heart Foundation (2000) European cardiovascular disease statistics

22. Cano A (2003) Blood flow and hemostasis. In: Schneider HPG (ed) Menopause: The State of the Art in Research and Management. Parthenon, London, pp 139145

23. Cano A, Van Baal WM (2001) The mechanisms of thrombotic risk induced by hormone replacement therapy. Maturitas 40:17-38

24. Ceresini G, Marchini L, Rebecchi I, Morganti S, Bertone L, Montanari I, Bacchi- Modena A, Sgarabotto M, Baldini M, Denti L, Ablondi F, Ceda GP, Valenti G (2003) Effects of raloxifene on carotid blood flow resistance and endothelium-dependent vasodilation in postmenopausal women. Atherosclerosis 167:121-127

25. Chen LY, Mehta P, Mehta JL (1996) Oxidized LDL decreases L-arginine uptake and nitric oxide synthase protein expression in human platelets: relevance of the effect of oxidized LDL on platelet function. Circulation 93: 1740-1746

26. Chen FPL, Lee N, Wang CH, Soong YK (1998) Effects of hormone replacement therapy on cardiovascular risk factors in postmenopausal women. Fertil Steril 69:267-273

27. Chin JH, Azhar S, Hoffman BB (1992) Inactivation of endothelial derived relaxing factor by oxidized lipoproteins. J Clin Invest 89(1):10-18

28. Christopher TA, Lopez BL, Stillwagon JC, Gao F, Gao E, Ma XL, Ohlstein EH, Yue TL

(2002) Idoxifene causes endothelium-dependent, nitric oxide-mediated vasorelaxation in male rats. Eur J Pharmacol 446:139-143

29. Clarkson TB (1994) Estrogens, progestins, and coronary heart disease in cynomolgus monkeys. Fertil Steril 62(Suppl 2):147S-151S

30. Clarkson TB, Anthony MS, Jerome CP (1998) Lack of effect of raloxifene on coronary artery atherosclerosis of postmenopausal monkeys. J Clin Endocrinol Metab 83:721726

31. Colacurci N, Manzella D, Fornaro F, Carbonella M, Paolisso G (2003) Endothelial function and menopause: effects of raloxifene administration. J Clin Endocrinol Metab 88:2135-2140

32. Couzin J (2004) Estrogen’s ties to COX-2 may explain heart disease gender gap. Science 306:1277

33. Cushman M, Costantino JP, Tracy RP, Song K, Buckley L, Roberts JD, Krag DN (2001) Tamoxifen and cardiac risk factors in healthy women: suggestion of an antiinflammatory effect. Arterioscler Thromb Vasc Biol 21:255-261

34. Daly E, Vessey MP, Hawkins MM, Carson JL, Gough P, Marsh S (1996) Risk of venous thromboembolism in users of hormone replacement therapy. Lancet 348: 977-980

35. Davison S, Davis SR (2003) New markers for cardiovascular disease risk in women: impact of endogenous estrogen status and exogenous postmenopausal hormone therapy. J Clin Endocrinol Metab 88:2470-2478

36. Decensi A, Robertson C, Viale G, Pigatto F, Johansson H, Kisanga ER, Veronesi P, Torrisi R, Cazzaniga M, Mora S, Sandri MT, Pelosi G, Luini A, Goldhirsch A, Lien, EA, Veronesi U (2003) A randomized trial of low-dose tamoxifen on breast cancer proliferation and blood estrogenic biomarkers. J Natl Cancer Inst 95: 779-790

37. De Leo V, la Marca A, Morgante G, Lanzetta D, Setacci C, Petraglia F (2001) Randomized control study of the effects of raloxifene on serum lipids and homocysteine in older women. Am J Obstet Gynecol 184:350-353.

38. Delmas PD, Bjarnason NH, Mitlak BH, Ravoux AC, Shah AS, Huster WJ, Draper M, Christiansen C (1997) Effects of raloxifene on bone mineral density, serum cholesterol concentrations, and uterine endometrium in postmenopausal women. N Engl J Med 337:1641-1647

39. Delmas PD, Ensrud KE, Adachi JD, Harper KD, Sarkar S, Gennari C, Reginster JY, Pols HA, Recker RR, Harris ST, Wu W, Genant HK, Black DM, Eastell R (2002) Multiple Outcomes of Raloxifene Evaluation Investigators Efficacy of raloxifene on vertebral fracture risk reduction in postmenopausal women with osteoporosis: four-year results from a randomized clinical trial. J Clin Endocrinol Metab 87: 3609-3617

40. de Valk-deRoo GW, Stehouwer CD, Meijer P, MijatovicV, Kluft C, Kenemans P, CohenF, Watts S, Netelenbos C (1999) Both raloxifene and estrogen reduce major cardiovascular risk factors in healthy postmenopausal women: a 2-year, placebo-controlled study. Arterioscler Thromb Vasc Biol 19:2993-3000

41. de Zwart LL, Meerman JH, Commandeur JN, Vermeulen NP (1999) Biomarkers of free radical damage applications in experimental animals and in humans. Free Radic Biol Med 26:202-226

42. Dubey RK, Tyurina YY, Tyurin VA, Gillespie DG, Branch RA, Jackson EK, Kagan VE (1999) Estrogen and tamoxifen metabolites protect smooth muscle cell membrane phospholipids against peroxidation and inhibit cell growth. Circ Res 84:229-239

43. Early Breast Cancer Trialists’ Collaborative Group (1998) Tamoxifen for early breast cancer: an overview of the randomised trials. Lancet 351:1451-1467

44. Elhage R, Arnal JF, Pieraggi MT, Duverger N, Fievet C, Faye JC, Bayard F (1997) 17 beta-estradiol prevents fatty streak formation in apolipoprotein E-deficient mice. Arterioscler Thromb Vasc Biol 17:2679-2684

45. Espinosa E, Oemar BS, Luscher TF (1996) 17 beta-Estradiol and smooth muscle cell proliferation in aortic cells of male and female rats. Biochem Biophys Res Commun 221:8-14

46. European Cardiovascular disease statistics. 2000 edition. British Heart Foundation

47. Figtree GA, Webb CM, Collins P (2000) Tamoxifen acutely relaxes coronary arteries by an endothelium-, nitric oxide-, and estrogen receptor-dependent mechanism. J Pharmacol Exp Ther 295:519-523

48. Friedewald WT (1996) Epidemiology of cardiovascular diseases. In: Bennett JC, Plum F (eds) Cecil Textbook of Medicine. Saunders, Philadelphia, pp 170-173

49. Fulimoto J, Sakaguchi H, Hirose R, Tamaya T (1998) Sex steroidal regulation of vessel permeability associated with vessel endothelial cadherin (v-cadherin). J Steroid Biochem Mol Biol 67:25-32

50. Fuster V, Badimon L, Badimon JJ, et al. (1992a) The pathogenesis of coronary artery disease and the acute coronary syndromes. N Engl J Med 326:242-250

51. Fuster V, Badimon L, Badimon JJ, et al. (1992b) The pathogenesis of coronary artery disease and the acute coronary syndromes. N Engl J Med 326:310-318

52. Garcfa-Martfnez MC, Labios M, Hermenegildo C, Tarin JJ, O’Connor E, Cano A (2004) The effect of hormone replacement therapy on Ca2+ mobilization and P-selectin (CD62P) expression in platelets examined under flow cytometry. Blood Coagul Fibrinolysis 15:1-8

53. Gaynor JS, Monnet E, Selzman C, Parker D, Kaufman L, Bryant HU, Mallinckrodt C, Wrigley R, Whitehill T, Turner AS (2000) The effect of raloxifene on coronary arteries in aged ovariectomized ewes. J Vet Pharmacol Ther 23:175-179

54. Ghosh U, Ganessunker D, Sattigeri VJ, Carlson KE, Mortensen DJ, Katzenellenbo- gen BS, Katzenellenbogen JA (2003) Estrogenic diazenes: heterocyclic non-steroidal estrogens of unusual structure with selectivity for estrogen receptor subtypes. Bioorg Med Chem 11:629-657

55. Gianni W, Ricci A, Gazzaniga P, Brama M, Pietropaolo M, Votano S, Patane F, Agliano AM, Spera G, Marigliano V, Ammendola S, Agnusdei D, Migliaccio S, Scan- durra R (2004) Raloxifene modulates interleukin-6 and tumor necrosis factor-alpha synthesis in vivo: results from a pilot clinical study. J Clin Endocrinol Metab 89:60976099

56. Gonzalez-Perez J, Crespo MJ (2003) Chronic effects of toremifene on the vasculature of menopause-induced rats. Vasc Pharmacol 40:261-268

57. Grainger DJ, Weissberg PL, Metcalfe JC (1993) Tamoxifen decreases the rate of proliferation of rat vascular smooth-muscle cells in culture by inducing production of transforming growth factor beta. Biochem J 294:109-112

58. Griendling KK, Alexander RW (1997) Oxidative stress and cardiovascular disease. Circulation 96:3264-3265

59. Griffiths KA, Sader MA, Skilton MR, Harmer JA, Celermajer DS (2003) Effects of raloxifene on endothelium-dependent dilation, lipoproteins, and markers of vascular function in postmenopausal women with coronary artery disease. J Am Coll Cardiol 42:698-704

60. Grodstein F, Stampfer MJ, Goldhaber SZ, Goldhaber SZ, Manson JE, Colditz GA, Speizer FE, et al. (1996) Prospective study of exogenous hormones and risk of pulmonary embolism in women. Lancet 348:983-987

61. Gross M, Steffes M, Jacobs DR Jr, Yu X, Lewis L, Lewis CE, Loria CM (2005) Plasma F2-isoprostanes and coronary artery calcification: the CARDIA study. Clin Chem 51:125-131

62. Haarbo J, Hansen BF, Christiansen C (1991) Hormone replacement therapy prevents coronary artery disease in ovariectomized cholesterol-fed rabbits. APMIS 99: 721-727

63. Haarbo J, Leth-Espensen P, Stender S, Christiansen C (1991) Estrogen monotherapy and combined estrogen-progestogen replacement therapy attenuate aortic accumulation of cholesterol in ovariectomized cholesterol-fed rabbits. J Clin Invest 87:1274-1279

64. Haines CJ, James AE, Panesar NS, Ngai TJ, Sahota DS, Jones RL, Chang AM (1999) The effect of percutaneous oestradiol on atheroma formation in ovariectomized cholesterol-fed rabbits. Atherosclerosis 143:369-375

65. Hannaford PC, Owen-Smith V (1998) Using epidemiological data to guide clinical practice: review of studies on cardiovascular disease and use of combined oral contraceptives. Br Med J 316:984-987

66. Harrington WR, Sheng S, Barnett DH, Petz LN, Katzenellenbogen JA, Katzenellen- bogen BS (2003) Activities of estrogen receptor alpha- and beta-selective ligands at diverse estrogen responsive gene sites mediating transactivation or transrepression. Mol Cell Endocrinol 206:13-22

67. Heikkinen AM, Niskanen L, Yla-Herttuala S, Luoma J, Tuppurainen MT, Komu- lainen M, Saarikoski S (1998) Postmenopausal hormone replacement therapy and autoantibodies against oxidized LDL. Maturitas 29:155-161

68. Hermenegildo C, Garcfa-Martfnez MC, Tarin JJ, Llacer A, Cano A (2001) The effect of oral hormone replacement therapy on lipoprotein profile, resistance of LDL to oxidation and LDL particle size. Maturitas 38:287-295

69. Hermenegildo C, Garcfa-Martfnez MC, Tarin JJ, Cano A (2002) Inhibition of low- density lipoprotein oxidation by the pure antiestrogens ICI 182780 and EM-652 (SCH 57068). Menopause 9:430-435

70. Herrington DM, Pusser BE, Riley WA, Thuren TY, Brosnihan KB, Brinton EA, MacLean DB (2000) Cardiovascular effects of droloxifene, a new selective estrogen receptor modulator, in healthy postmenopausal women. Arterioscler Thromb Vasc Biol 20:1606-1612

71. Herrington DM, Brosnihan KB, Pusser BE, Seely EW, Ridker PM, Rifai N, MacLean DB (2001) Differential effects of E and droloxifene on C-reactive protein and other markers of inflammation in healthy postmenopausal women. J Clin Endocrinol Metab 86:42164222

72. Hodgin JB, Krege JH, Reddick RL, Korach KS, Smithies O, Maeda N (2001) Estrogen receptor alpha is a major mediator of 17beta-estradiol’s atheroprotective effects on lesion size in Apoe-/- mice. J Clin Invest 107:333-340

73. Hodis HN, Mack WJ, Azen SP, Lobo RA, Shoupe D, Mahrer PR, Faxon DP, Cashin- Hemphill L, Sanmarco ME, French WJ, Shook TL, Gaarder TD, Mehra AO, Rabbani R, Sevanian A, Shil AB, Torres M, Vogelbach KH, Selzer RH, Women’s Estrogen-Progestin Lipid-Lowering Hormone Atherosclerosis Regression Trial Research Group (2003) Hormone therapy and the progression of coronary-artery atherosclerosis in postmenopausal women. N Engl J Med 349:535-545

74. Hoogerbrugge N, Zillikens MC, Jansen H, Meeter K, Deckers JW, Birkenhager JC (1998) Estrogen replacement decreases the level of antibodies against oxidized low-density lipoprotein in postmenopausal women with coronary heart disease. Metabolism 47:675-680

75. Hough JL, Zilversmit DB (1986) Effect of 17 beta estradiol on aortic cholesterol content and metabolism in cholesterol-fed rabbits. Arteriosclerosis 6:57-63

76. Hozumi Y, Kawano M, Miyata M (1997) Severe hypertriglyceridemia caused by tamoxifen-treatment after breast cancer surgery. Endocr J 44:745-749

77. Hulley S, Grady D, Bush T, Furberg C, Herrington D, Riggs B, Vittinghoff E (1998) Randomized trial of estrogen plus progestin for secondary prevention of coronary heart disease in postmenopausal women. Heart and Estrogen/progestin Replacement Study (HERS) Research Group. J Am Med Assoc 280:605-613

78. Hutchison SJ, Chou TM, Chatterjee K, Sudhir K (2001) Tamoxifen is an acute, estrogenlike, coronary vasodilator of porcine coronary arteries in vitro. J Cardiovasc Pharmacol 38:657-665

79. Hwang SJ, Ballantyne CM, Sharrett AR, Smith LC, Davis CE, Gotto AM Jr, Boerwinkle E (1997) Circulating adhesion molecules VCAM-1, ICAM-1, and E-selectin in carotid atherosclerosis and incident coronary heart disease cases: the Atherosclerosis Risk In Communities (ARIC) study. Circulation 96:4219-4225

80. Jayachandran M, Mukherjee R, Steinkamp T, Labreche P, Bracamonte MP, Okano H, Owen WG, Miller VM (2005) Differential effects of 17{beta}-estradiol, conjugated equine estrogen and raloxifene on mRNA expression, aggregation and secretion in platelets. Am J Physiol Heart Circ Physiol 288:H2355-362

81. Jick H, Derby LE, Myers MW, Vasilakis C, Newton KM (1996) Risk of hospital admission for idiopathic venous thromboembolism among users of postmenopausal oestrogens. Lancet 348:981-983

82. Joensuu H, Holli K, Oksanen H, Valavaara R (2000) Serum lipid levels during and after adjuvant toremifene or tamoxifen therapy for breast cancer. Breast Cancer Res Treat 63:225-234

83. Jokela H, Dastidar P, Rontu R, Salomaki A, Teisala K, Lehtimaki T, Punnonen R

(2003) Effects of long-term estrogen replacement therapy versus combined hormone replacement therapy on nitric oxide-dependent vasomotor function. J Clin Endocrinol Metab 88:4348-4354

84. Kanel KT, Wolmark N, Thompson PD (1997) Delayed severe hypertriglyceridemia from tamoxifen. N Engl J Med 337:281

85. Karas RH, Patterson BL, Mendelsohn ME (1994) Human vascular smooth muscle cells contain functional estrogen receptor. Circulation 89:1943-1950

86. Klinge CM (2001) Estrogen receptor interaction with estrogen response elements. Nucleic Acids Res 29:2905

87. Koh KK, Bui MN, Mincemoyer R, Cannon RO III (1997) Effects of hormone therapy on inflammatory cell adhesion molecules in postmenopausal healthy women. Am J Cardiol 80:1505-1507

88. Kugiyama K, Kerns SA, Morrisett JD, Roberts R, Henry PD (1990) Impairment of endothelium-dependent arterial relaxation by lysolecithin in modified low-density lipoproteins. Nature 344:160-162

89. Lavigne MC, Ramwell PW, Clarke R (1999) Inhibition of estrogen receptor function promotes porcine coronary artery smooth muscle cell proliferation. Steroids 64:472480

90. Li L, Haynes MP, Bender JR (2003) Plasma membrane localization and function of the estrogen receptor alpha variant (ER46) in human endothelial cells. Proc Natl Acad Sci USA 100:4807-4812

91. Liu TZ, Stern A, Morrow JD (1998) The isoprostanes: unique bioactive products of lipid peroxidation: an overview. J Biomed Sci 5:415-420

92. Marsh MM, Walker VR, Curtiss LK, Banka CL (1999) Protection against atherosclerosis by estrogen is independent of plasma cholesterol levels in LDL receptor-deficient mice. J Lipid Res 40:893-900

93. Mendelsohn ME (2000) Mechanisms of estrogen action in the cardiovascular system. J Steroid Biochem Mol Biol 74:337-343

94. Mendelsohn ME (2002) Genomic and nongenomic effects of estrogen in the vasculature. Am J Cardiol 90(1A):3F-6F

95. Mijatovic V, Netelenbos C, van der Mooren MJ, de Valk-de Roo GW, Jakobs C, Kene- mans P (1998) Randomized, double-blind, placebo-controlled study of the effects of raloxifene and conjugated equine estrogen on plasma homocysteine levels in healthy postmenopausal women. Fertil Steril 70:1085-1089

96. Miller M (1998) Is hypertriglyceridaemia an independent risk factor for coronary heart disease? The epidemiological evidence. Eur Heart J 19(Suppl H):H18-22

97. Miller ME, Dores GM, Thorpe SL, Akerley WL (1994) Paradoxical influence of estrogenic hormones on platelet-endothelial cell interactions. Thromb Res 74:577-594

98. Miller ME, Thorpe SL, Dores GM (1995) Influence of hormones on platelet intracellular calcium. Thromb Res 77:515-530

99. Moraghan T, Antoniucci DM, Grenert JP, Sieck GC, Johnson C, Miller VM, Fitzpatrick LA (1996) Differential response in cell proliferation to beta estradiol in coronary arterial vascular smooth muscle cells obtained from mature female versus male animals. Endocrinology 137:5174-5177

100. Morel DW, Hessler JR, Chisholm GM (1983) Low density lipoprotein cytotoxicity induced by free radical peroxidation of lipid. J Lipid Res 24:1070-1076

101. Mori-Abe A, Tsutsumi S, Takahashi K, Toya M, Yoshida M, Du B, Kawagoe J, Naka- hara K, Takahashi T, Ohmichi M, Kurachi H (2003) Estrogen and raloxifene induce apoptosis by activating p38 mitogen-activated protein kinase cascade in synthetic vascular smooth muscle cells. J Endocrinol 178:417-426

102. Mosca L, Barrett-Connor E, Wenger NK, Collins P, Grady D, Kornitzer M, Moscarelli E, Paul S, Wright TJ, Helterbrand JD, Anderson PW (2001a) Design and methods of the Raloxifene Use for The Heart (RUTH) study. Am J Cardiol 88: 392-395

103. Mosca L, Harper K, Sarkar S, O’Gorman J, Anderson PW, Cox DA, Barrett-Connor E (2001b) Effect of raloxifene on serum triglycerides in postmenopausal women: influence of predisposing factors for hypertriglyceridemia. Clin Ther 23:1552-1565

104. Mosca L, Appel LJ, Benjamin EJ, Berra K, Chandra-Strobos N, Fabunmi RP, Grady D, Haan CK, Hayes SN, Judelson DR, Keenan NL, McBride P, Oparil S, Ouyang P, Oz MC, Mendelsohn ME, Pasternak RC, Pinn VW, Robertson RM, Schenck-Gustafsson K, Sila CA, Smith SC Jr, Sopko G, Taylor AL, Walsh BW, Wenger NK, Williams CL, American Heart Association (2004) Evidence-based guidelines for cardiovascular disease prevention in women. Circulation 109:672-693

105. Muthyala RS, Sheng S, Carlson KE, Katzenellenbogen BS, Katzenellenbogen JA (2003) Bridged bicyclic cores containing a 1,1-diarylethylene motif are high-affinity subtype- selective ligands for the estrogen receptor. J Med Chem 46:1589-1602

106. Nakano Y, Oshima T, Matsuura H, Kajiyama G, Kambe M (1998) Effect of 17beta- estradiol on inhibition of platelet aggregation in vitro is mediated by an increase in NO synthesis. Arterioscler Thromb Vasc Biol 18:961-967

107. Navab M, Berliner JA, Watson AD, et al. (1996) The Yin and Yang of oxidation in the development of the fatty streak: a review based on the 1994 George Lyman Duff Memorial Lecture. Arterioscler Thromb Vasc Biol 16:831-842

108. Niebauer J, Maxwell AJ, Lin PS, Wang D, Tsao PS, Cooke JP (2003) NOS inhibition accelerates atherogenesis: reversal by exercise. Am J Physiol Heart Circ Physiol 285:H535- 540

109. Oguogho A, Kritz H, Wagner O, Sinzinger H (2001) 6-oxo-PGF(1 alpha) and 8-epi- PGF(2 alpha) in the arterial wall layers of various species: a comparison between intact and atherosclerotic areas. Prostaglandins Leukot Essent Fatty Acids 64:167-171

110. Oviedo PJ, Hermenegildo C, Cano A (2004) Raloxifene increases the capacity of serum to promote prostacyclin release in human endothelial cells: implication of COX-1 and COX-2. Menopause 11:430-437

111. Oviedo P, Hermenegildo C, Tarin JJ, Cano A (2005) Raloxifene promotes prostacyclin release in human endothelial cells role of COX-1 and COX-2. Fertil Steril 83:1822-1829

112. Pérez-Gutthan S, Garcia-Rodriguez LA, Castellsague J, Duque-Oliart A (1997) Hormone replacement therapy and risk of venous thromboembolism: population based case-control study. Br Med J 314:796-800

113. Perrault LP, Malo O, Bidouard JP, Villeneuve N, Vilaine JP, Vanhoutte PM (2003) Inhibiting the NO pathway with intracoronary L-NAME infusion increases endothelial dysfunction and intimal hyperplasia after heart transplantation. J Heart Lung Transplant 22:439-451

114. Pratico D (1999) F(2)-isoprostanes: sensitive and specific non-invasive indices of lipid peroxidation in vivo. Atherosclerosis 147:1-10

115. Rader DJ (2000) Inflammatory markers of coronary risk. N Engl J Med 343:1179

116. Rahimian R, Dube GP, Toma W, Dos Santos N, McManus BM, van Breemen C (2002) Raloxifene enhances nitric oxide release in rat aorta via increasing endothelial nitric oxide mRNA expression. Eur J Pharmacol 434:141-149

117. Reckless J, Metcalfe JC, Grainger DJ (1997) Tamoxifen decreases cholesterol sevenfold and abolishes lipid lesion development in apolipoprotein E knockout mice. Circulation 95:1542-1548

118. Reid IR, Eastell R, Fogelman I, Adachi JD, Rosen A, Netelenbos C, Watts NB, Seeman E, Ciaccia AV, Draper MW (2004) A comparison of the effects of raloxifene and conjugated equine estrogen on bone and lipids in healthy postmenopausal women. Arch Intern Med 164:871-879

119. Reis SE, Costantino JP, Wickerham DL, Tan-ChiuE, WangJ, KavanahM (2001) Cardiovascular effects of tamoxifen in women with and without heart disease: breast cancer prevention trial. National Surgical Adjuvant Breast and Bowel Project Breast Cancer Prevention Trial Investigators. J Natl Cancer Inst 93:16-21

120. Resnick N, Gimbrone MA Jr (1995) Hemodynamic forces are complex regulators of endothelial gene expression. FASEB J 9:874-882

121. Ricciardelli C, Horsfall DJ, Sykes PJ, Marshall VR, Tilley WD (1994) Effects of oestradiol-17 beta and 5 alpha-dihydrotestosterone on guinea-pig prostate smooth muscle cell proliferation and steroid receptor expression in vitro. J Endocrinol 140:373383

122. Ridker PM (2001) High-sensitivity C-reactive protein: potential adjunct for global risk assessmentin the primary prevention of cardiovascular disease. Circulation 103:18131818

123. Ridker PM, Rifai N, Pfeffer M, Sacks F, Lepage S, Braunwald E (2000) Elevation of tumor necrosis factor-alpha and increased risk of recurrent coronary events after myocardial infarction. Circulation 101:2149-2153

124. Rosendaal FR (1999) Venous thrombosis: a multicausal disease. Lancet 353: 1167-73

125. Ross R (1999) Atherosclerosis - an inflammatory disease. N Engl J Med 340:115-126

126. Rossouw JE, Anderson GL, Prentice RL, LaCroix AZ, Kooperberg C, Stefanick ML, et al. (2002) Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women’s Health Initiative randomized controlled trial. J Am Med Assoc 288:321-333

127. Saarto T, Blomqvist C, Ehnholm C, Taskinen MR, Elomaa I (1996) Antiatherogenic effects of adjuvant antiestrogens: a randomized trial comparing the effects of tamoxifen

and toremifene on plasma lipid levels in postmenopausal women with node-positive breast cancer. J Clin Oncol 14:429-433

128. Saitta A, Altavilla D, Cucinotta D, Morabito N, Frisina N, Corrado F, D’Anna R, Lasco A, Squadrito G, Gaudio A, Cancellieri F, Arcoraci V, Squadrito F (2001) Randomized, double-blind, placebo-controlled study on effects of raloxifene and hormone replacement therapy on plasma no concentrations, endothelin-1 levels, and endothelium- dependent vasodilation in postmenopausal women. Arterioscler Thromb Vasc Biol 21:1512-1519

129. Santanam N, Shern-Brewer R, McClatchey R, Castellano PZ, Murphy AA, Voelkel S, Parthasarathy S (1998) Estradiol as an antioxidant: incompatible with its physiological concentrations and function. J Lip Res 39:2111-2118

130. Sarrel PM, Nawaz H, Chan W, Fuchs M, Katz DL (2003) Raloxifene and endothelial function in healthy postmenopausal women. Am J Obstet Gynecol 188:304-309

131. Sbarouni E, Flevari P, Kroupis C, Kyriakides ZS, Koniavitou K, Kremastinos DT (2003) The effects of raloxifene and simvastatin on plasma lipids and endothelium. Cardiovasc Drugs Ther 17:319-323

132. Seli E, Pehlivan T, Selam B, Garcia-Velasco JA, Arici A (2002) Estradiol down- regulates MCP-1 expression in human coronary artery endothelial cells. Fertil Steril 77: 542-547

133. Selzman CH, Turner AS, Gaynor JS, Miller SA, Monnet E, Harken AH (2002) Inhibition of intimal hyperplasia using the selective estrogen receptor modulator raloxifene. Arch Surg 137:333-336

134. Silverstein MD, Heit JA, Mohr DN, et al. (1998) Trends in the incidence of deep vein thrombosis and pulmonary embolism: a 25-year population-based study. Arch Intern Med 158:585-593

135. Simoncini T, Genazzani AR (2000) Raloxifene acutely stimulates nitric oxide release from human endothelial cells via an activation of endothelial nitric oxide synthase. J Clin Endocrinol Metab 85:2966-2969

136. Simoncini T, De Caterina R, Genazzani AR (1999) Selective estrogen receptor modulators: different actions on vascular cell adhesion molecule-1 (VCAM-1) expression in human endothelial cells. J Clin Endocrinol Metab 84:815-818

137. Smolders RG, Vogelvang TE, Mijatovic V, van Baal WM, Neele SJ, Netelenbos JC, Kenemans P, van der Mooren MJ (2002) A 2-year, randomized, comparative, placebo- controlled study on the effects of raloxifene on lipoprotein(a) and homocysteine. Maturitas 41:105-114

138. Somjen D, Kohen F, Jaffe A, Amir-Zaltsman Y, Knoll E, Stern N (1998) Effects of gonadal steroids and their antagonists on DNA synthesis in human vascular cells. Hypertension 32:39-45

139. Song J, Wan Y, Rolfe BE, Campbell JH, Campbell GR (1998) Effect of estrogen on vascular smooth muscle cells is dependent upon cellular phenotype. Atherosclerosis 140:97-104

140. Speroff L (2002) The impact of the Women’s Health Initiative on clinical practice. J Soc Gynecol Invest 9:251-253

141. Spyridopoulos I, Sullivan AB, Kearney M, Isner JM, Losordo DW (1997) Estrogen- receptor-mediated inhibition of human endothelial cell apoptosis. Estradiol as a survival factor. Circulation 95:1505-1514

142. Stamatelopoulos KS, Lekakis JP, Poulakaki NA, Papamichael CM, Venetsanou K, Az- naouridis K, Protogerou AD, Papaioannou TG, Kumar S, Stamatelopoulos SF (2004) Tamoxifen improves endothelial function and reduces carotid intima-media thickness in postmenopausal women. Am Heart J 147:1093-1099

143. Steinberg D (1997) Low density lipoprotein oxidation and its pathobiological significance. J Biol Chem 272:20963-20966

144. Takahashi K, Ohmichi M, Yoshida M, Hisamoto K, Mabuchi S, Arimoto-Ishida E, Mori A, Tsutsumi S, Tasaka K, Murata Y, Kurachi H (2003) Both estrogen and raloxifene cause G1 arrest of vascular smooth muscle cells. J Endocrinol 178: 319-329

145. Tangirala RK, Rubin EM, Palinski W (1995) Quantitation of atherosclerosis in murine models: correlation between lesions in the aortic origin and in the entire aorta, and differences in the extent of lesions between sexes in LDL receptor-deficient and apolipoprotein E-deficient mice. J Lipid Res 36:2320-2328

146. Tatchum-Talom R, Martel C, Labrie F, Marette A (2003) Acute vascular effects of the selective estrogen receptor modulator EM-652 (SCH 57068) in the rat mesenteric vascular bed. Cardiovasc Res 57:535-543

147. Thorin E, Pham-Dang M, Clement R, Mercier I, Calderone A (2003) Hyper-reactivity of cerebral arteries from ovariectomized rats: therapeutic benefit of tamoxifen. Br J Pharmacol 140:1187-1192

148. Todaka T, Yokoyama C, Yanamoto H, Hashimoto N, Nagata I, Tsukahara T, Hara S, Hatae T, Morishita R, Aoki M, Ogihara T, Kaneda Y, Tanabe T (1999) Gene transfer of human prostacyclin synthase prevents neointimal formation after carotid balloon injury in rats. Stroke 30:419-426

149. Uint L, Gebara OC, Pinto LB, Wajngarten M, Boschcov P, da Luz PL, Gidlund M (2003) Hormone replacement therapy increases levels of antibodies againstheatshock protein 65 and certain species of oxidized low density lipoprotein. Braz J Med Biol Res 36:491494

150. Vandenbroucke JP, Rosing J, Bloemenkamp KW, Middeldorp S, Helmerhorst FM, Bouma BN, Rosendaal FR (2001) Oral contraceptives and the risk of venous thrombosis. N Engl J Med 344:1527-1535

151. Varas-Lorenzo C, Garcfa-Rodrfguez LA, Cattaruzzi C, Troncon MG, Agostinis L, Pérez- Gutthann S (1998) Hormone replacement therapyand the risk of hospitalization for venous thromboembolism: a population-based study in southern Europe. Am J Epidemiol 147:387-390

152. Vargas R, Hewes B, Rego A, Farhat MY, Suarez R, Ramwell PW (1996) Estradiol effect on rate of proliferation of rat carotid segments: effect of gender and tamoxifen. J Cardiovasc Pharmacol 27:495-499

153. Vassalle C, Botto N, Andreassi MG, Berti S, Biagini A (2003) Evidence for enhanced 8- isoprostane plasma levels, as index of oxidative stress in vivo, in patients with coronary artery disease. Coron Artery Dis 14:213-218

154. Venkov C, Rankin A, Vaughan D (1996) Identification of authentic estrogen receptor in cultured endothelial cells: a potential mechanism for steroid hormone regulation of endothelial function. Circulation 94:727-733

155. Vogelvang TE, Mijatovic V, Kenemans P, Teerlink T, van der Mooren MJ (2004) HMR 3339, a novel selective estrogen receptor modulator, reduces total cholesterol, low- density lipoprotein cholesterol, and homocysteine in healthy postmenopausal women. Fertil Steril 82:1540-1549

156. Wagner JD, Clarkson TB, St Clair RW, Schwenke DC, Shively CA, Adams MR (1991) Estrogen and progesterone replacement therapy reduces low density lipoprotein accumulation in the coronary arteries of surgically postmenopausal cynomolgus monkeys. J Clin Invest 88:1995-2002

157. Walsh BW, Cox DA, Sashegyi A, Dean RA, Tracy RP, Anderson PW (2001) Role of tumor necrosis factor-alpha and interleukin-6 in the effects of hormone replacement

therapy and raloxifene on C-reactive protein in postmenopausal women. Am J Cardiol 88:825-828

158. Walsh BW, Kuller LH, Wild RA, Paul S, Farmer M, Lawrence JB, et al. (1998) Effects of raloxifene on serum lipids and coagulation factors in healthy postmenopausal women. J Am Med Assoc 279:1445-1451

159. Walsh BW, Paul S, Wild RA, Dean RA, Tracy RP, Cox DA, Anderson PW (2000) The effects of hormone replacement therapy and raloxifene on C-reactive protein and homocysteine in healthy postmenopausal women: a randomized, controlled trial. J Clin Endocrinol Metab 85:214-218

160. Wassmann S, Laufs U, Stamenkovic D, Linz W, Stasch JP, Ahlbory K, Rosen R, Bohm M, Nickenig G (2002) Raloxifene improves endothelial dysfunction in hypertension by reduced oxidative stress and enhanced nitric oxide production. Circulation 105:20832091

161. White RH (2003) The epidemiology of venous thromboembolism. Circulation 107(23 Suppl 1):I4-8

162. Writing Group for the PEPI Trial (1995) Effects of estrogen or estrogen/progestin regimens on heart disease risk factors in postmenopausal women. The Postmenopausal Estrogen/Progestin Interventions (PEPI) Trial. J Am Med Assoc 273:199-208

163. Ylikorkala O, Cacciatore B, Halonen K, Lassila R, Lammintausta R, Rutanen EM, Heikkinen J, Komi J (2003) Effects of ospemifene, a novel SERM, on vascular markers and function in healthy, postmenopausal women. Menopause 10:440-447

164. Yue TL, Vickery-Clark L, Louden CS, Gu JL, Ma XL, Narayanan PK, Li X, Chen J, Storer B, Willette R, Gossett KA, Ohlstein EH (2000) Selective estrogen receptor modulator idoxifene inhibits smooth muscle cell proliferation, enhances reendothelial- ization, and inhibits neointimal formation in vivo after vascular injury. Circulation 102(Suppl 3):III281-288

165. Zanger D, Yang BK, Ardans J, Waclawiw MA, Csako G, Wahl LM, Cannon RO III (2000) Divergent effects of hormone therapy on serum markers of inflammation in postmenopausal women with coronary artery disease on appropriate medical management. J Am Coll Cardiol 36:1797-1802

166. Zuckerman SH, Bryan N (1996) Inhibition of LDL oxidation and myeloperoxidase dependent tyrosyl radical formation by the selective estrogen receptor modulator raloxifene (LY139481 HCL). Atherosclerosis 126:65-75

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