Effects of raloxifene on serum lipids and coagulation factors in healthy postmenopausal women

Impact of Low Bone Mineral Content Index on Cardiovascular Outcomes in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

The prognostic value of bone mineral content (BMC) for the clinical outcomes of patients with coronary artery disease (CAD) remains unknown. The present study evaluated the association between BMC index (BMCI) and cardiovascular events between January 2020 to June 2021, in consecutive patients (n = 257) with CAD undergoing percutaneous coronary intervention (PCI) at the Nagano Municipal Hospital. BMCI was measured using bioelectrical impedance analysis and calculated as the BMC divided by height squared. Patients were classified as low (<0.918) or high BMCI (≥0.918) groups according to the receiver operating characteristics curve analysis for the primary endpoint, major adverse cardiovascular events (MACE), including cardiovascular death, spontaneous myocardial infarction, stroke, and any revascularization. During a median follow-up of 744 days, the low BMCI group (n = 152) had an increased risk of MACE compared with the high group (n = 105) (19.7 vs 6.7%, P = .004). A low BMCI was significantly associated with MACE in the multivariable Cox and the Inverse Probability of Treatment Weighting analyses (hazard ratio: 3.16, 95% confidence interval: 1.15-8.67, P = .025). In conclusion, among patients with CAD undergoing PCI, BMCI was a predictor for cardiovascular events. Further research is required to determine whether medical interventions for BMC can improve patient prognosis.

The Cardiovascular Risks Associated with Aromatase Inhibitors, Tamoxifen, and GnRH Agonists in Women with Breast Cancer

PURPOSE OF REVIEW

Cardiovascular disease accounts for up to 10% of all-cause mortality in women with a diagnosis of breast cancer, and the causes for this are multifaceted. Many women at risk of or with a diagnosis of breast cancer are on endocrine-modulating therapies. It is therefore important to understand the effect of hormone therapies on cardiovascular outcomes in breast cancer patients to mitigate against any adverse effects and to identify those most at risk so that they can be proactively managed. Here we discuss the pathophysiology of these agents, their effect on the cardiovascular system, and the latest evidence on their cardiovascular risks association.

RECENT FINDINGS

Tamoxifen appears to be cardioprotective during treatment but not over the longer term, while the effect of AIs on cardiovascular outcomes remains controversial. Heart failure outcomes remain understudied, and the cardiovascular effects of gonadotrophin-releasing hormone agonists (GNRHa) in women need further research, especially since data from men with prostate cancer have indicated an increased risk of cardiac events in GNRHa users. There remains a need for a greater understanding of the effects of hormone therapies on cardiovascular outcomes in breast cancer patients. Further areas of research in this area include developing evidence to better define the optimal preventive and screening methods for cardiovascular effects and the risk factors for patients on hormonal therapies.

Osteoporosis and cardiovascular disease: a review

BACKGROUND

Osteoporosis and cardiovascular disease are common diseases encountered globally, especially with advancing age. Osteoporosis occurs when there is a loss of bone mineral density leading to increased predisposition to fragility fracture. The conventional perception of osteoporosis is purely as a metabolic bone disease. However, there are mounting reports from recent studies that osteoporosis could be seen as a risk factor for cardiovascular disease just like other traditional risk factors such as hypertension, dyslipidaemia and diabetes. This is a paradigm shift with regards to the outlook of osteoporosis. Osteoporosis and cardiovascular disease have similar risk factors, including diabetes, smoking, excess alcohol, sedentary lifestyle, ageing and dyslipidaemia. This may partly explain the link between osteoporosis and cardiovascular disease. In addition, both osteoporosis and atherosclerosis, which underlies most cardiovascular disease, are both characterized by low grade chronic inflammation. Moreover, the processes involved in the calcification of atheroma are similar to what is seen in bone remodeling. Both processes also involve similar regulators such as osteoprotegerin and related proteins such as osteonectin, osteopontin and type 1 collagen are found in bone matrix and atheromatous plaques.

CONCLUSION

There is emerging evidence that individuals with osteoporosis are also at an increased risk of coronary artery disease and stroke even after controlling for other factors. The traditional risk factors for cardiovascular disease also predispose people to developing osteoporosis, suggesting that the same mechanism may be causing the two. Moreover, a number of anti-osteoporotic drugs have also been largely linked with cardiovascular disease. This calls for a change in the view of osteoporosis as a metabolic disease but as a cardio-metabolic disorder thereby emphasizing the need for intensified preventive strategies for the disease.

Brain nuclear receptors and cardiovascular function

Brain-heart interaction has raised up increasing attentions. Nuclear receptors (NRs) are abundantly expressed in the brain, and emerging evidence indicates that a number of these brain NRs regulate multiple aspects of cardiovascular diseases (CVDs), including hypertension, heart failure, atherosclerosis, etc. In this review, we will elaborate recent findings that have established the physiological relevance of brain NRs in the context of cardiovascular function. In addition, we will discuss the currently available evidence regarding the distinct neuronal populations that respond to brain NRs in the cardiovascular control. These findings suggest connections between cardiac control and brain dynamics through NR signaling, which may lead to novel tools for the treatment of pathological changes in the CVDs.

Impact of anti-oestrogen therapy on lipoprotein(a) in postmenopausal women: a systematic review and meta-analysis of double-blind placebo-controlled clinical studies

PURPOSE

The potential mechanisms of endocrine therapy for thrombosis remain currently unclear, and more studies are warranted for further investigation and elucidation. However, high plasma concentration of lipoprotein(a) (Lp(a)) is a recognized prothrombotic factor. The aim of our study was to systematically evaluate the effect of different anti-oestrogen therapy on plasma Lp(a) level in postmenopausal women.

METHODS

A systematic literature search was conducted in multiple electronic databases to identify the randomized, double-blind, placebo-controlled clinical studies on this topic. Effect size for changes in Lp(a) was expressed as mean difference (MD) and 95% confidence intervals (CI).

RESULTS

Data were pooled from 10 clinical trials comprising 24 treatment arms, which included 2049 women (1128 women in the active-treated arms and 921 women in the control arms). Meta-analysis of data suggested that anti-oestrogen therapy in women significantly reduced Lp(a) [MD = -5.92% (95%CI: -9.05%,-2.8%)].

CONCLUSIONS

This observation is of both clinical and pathophysiological relevance, also in view that the identification of molecular determinants and cellular pathways implicated in Lp(a) synthesis and metabolism is still of concern as a critical issue in lipidology and CV prevention.

Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement

This 2022 European Atherosclerosis Society lipoprotein(a) [Lp(a)] consensus statement updates evidence for the role of Lp(a) in atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis, provides clinical guidance for testing and treating elevated Lp(a) levels, and considers its inclusion in global risk estimation. Epidemiologic and genetic studies involving hundreds of thousands of individuals strongly support a causal and continuous association between Lp(a) concentration and cardiovascular outcomes in different ethnicities; elevated Lp(a) is a risk factor even at very low levels of low-density lipoprotein cholesterol. High Lp(a) is associated with both microcalcification and macrocalcification of the aortic valve. Current findings do not support Lp(a) as a risk factor for venous thrombotic events and impaired fibrinolysis. Very low Lp(a) levels may associate with increased risk of diabetes mellitus meriting further study. Lp(a) has pro-inflammatory and pro-atherosclerotic properties, which may partly relate to the oxidized phospholipids carried by Lp(a). This panel recommends testing Lp(a) concentration at least once in adults; cascade testing has potential value in familial hypercholesterolaemia, or with family or personal history of (very) high Lp(a) or premature ASCVD. Without specific Lp(a)-lowering therapies, early intensive risk factor management is recommended, targeted according to global cardiovascular risk and Lp(a) level. Lipoprotein apheresis is an option for very high Lp(a) with progressive cardiovascular disease despite optimal management of risk factors. In conclusion, this statement reinforces evidence for Lp(a) as a causal risk factor for cardiovascular outcomes. Trials of specific Lp(a)-lowering treatments are critical to confirm clinical benefit for cardiovascular disease and aortic valve stenosis.

To clot, or not to clot: The dilemma of hormone treatment options for menopause

Untreated menopause may have serious health implications, but treatments can have dangerous side effects. We evaluate menopausal symptoms as well as available treatments -the routes of administration and their effect on blood coagulation. Menopausal females may experience hot flushes, vulva- and vaginal atrophy and osteoporosis. Many treatments are available to relieve these symptoms such as Conjugated Equine Estrogen and bioidentical hormones. The routes of administration include oral and transdermal. Hormones that are administered orally undergo a hepatic first pass metabolism. The by-products have a lower efficacy and possibly enhanced side effects. Furthermore, hormone treatments influence the coagulation cascade through coagulation factors or their regulators. Increased coagulation poses a risk for venous thromboembolism. Currently a definite conclusion on whether the side effects from hormone treatments exceed the risk of untreated menopause cannot be made. However, a more individualised approach to hormone treatments may be the most feasible solution to this dilemma.

Advances in Our Understanding of the Mechanism of Action of Drugs (including Traditional Chinese Medicines) for the Intervention and Treatment of Osteoporosis

Osteoporosis (OP) is known as a silent disease in which the loss of bone mass and bone density does not cause obvious symptoms, resulting in insufficient treatment and preventive measures. The losses of bone mass and bone density become more severe over time and an only small percentage of patients are diagnosed when OP-related fractures occur. The high disability and mortality rates of OP-related fractures cause great psychological and physical damage and impose a heavy economic burden on individuals and society. Therefore, early intervention and treatment must be emphasized to achieve the overall goal of reducing the fracture risk. Anti-OP drugs are currently divided into three classes: antiresorptive agents, anabolic agents, and drugs with other mechanisms. In this review, research progress related to common anti-OP drugs in these three classes as well as targeted therapies is summarized to help researchers and clinicians understand their mechanisms of action and to promote pharmacological research and novel drug development.

Structure-based design and synthesis of conformationally constrained derivatives of methyl-piperidinopyrazole (MPP) with estrogen receptor (ER) antagonist activity

Nuclear Estrogen receptors (ER) are cytoplasmic proteins; translocated to the nucleus to induce transcriptional signals after getting bound to the estrogen hormone. ER activation implicated in cancer cell proliferation of female reproductive organs. Thus, the discovery of ER antagonists is a reliable strategy to combat estrogen-dependent breast cancer. Endometrial carcinoma is one of the complications encountered upon long-term therapy by selective estrogen receptor modulators (SERMs) like Tamoxifen (TMX) and methyl piperidinopyrazole (MPP). Thus, the ER-full antagonist is a solution to improve the safety of this class of therapeutics during the treatment of breast cancer. We selected MPP as a lead structure to design conformationally constrained analogs. Structural rigidification is a proven strategy to transform the SERMs into full antagonists. Accordingly, we synthesized 7-methoxy-3-(4-methoxyphenyl)-4,5-dihydro-2H-benzo[g]indazoles (4), (6a-c),(8-12) along with the biphenolic counterparts(13-19)that are the anticipated active metabolites. The 4-nitrophenyl derivative(4)is with the most balanced profile regardingthe in vivoanti-uterotrophic potential (EC₅₀ = 4.160 μM); and the cytotoxicity assay of the corresponding active metabolite(13)against ER+ breast cancer cell lines (MCF-7 IC₅₀ = 7.200 μM, T-47D IC₅₀ = 11.710 μM). The inconsiderable uterotrophic activities of the elaborated ER-antagonists and weak antiproliferative activity of the compound(13)against ovarian cancer (SKOV-3 IC₅₀ = 29.800 μM) highlighted it as a good start point to elaborate potential ER-full antagonists devoid of endometrial carcinoma. Extending the pendant chain that protrudes from the 2-(4-(substituted)-phenyl) ring of the new benzo-indazoles is recommended for enhancing the potency based on the binding mode of compound(13)in the ligand-binding domain (LBD) of ER.

Hormone Therapy in Menopause: Concepts, Controversies, and Approach to Treatment

Hormone therapy (HT) is an effective treatment for menopausal symptoms, including vasomotor symptoms and genitourinary syndrome of menopause. Randomized trials also demonstrate positive effects on bone health, and age-stratified analyses indicate more favorable effects on coronary heart disease and all-cause mortality in younger women (close proximity to menopause) than in women more than a decade past menopause. In the absence of contraindications or other major comorbidities, recently menopausal women with moderate or severe symptoms are appropriate candidates for HT. The Women's Health Initiative (WHI) hormone therapy trials-estrogen and progestin trial and the estrogen-alone trial-clarified the benefits and risks of HT, including how the results differed by age. A key lesson from the WHI trials, which was unfortunately lost in the posttrial cacophony, was that the risk:benefit ratio and safety profile of HT differed markedly by clinical characteristics of the participants, especially age, time since menopause, and comorbidity status. In the present review of the WHI and other recent HT trials, we aim to provide readers with an improved understanding of the importance of the timing of HT initiation, type and route of administration, and of patient-specific considerations that should be weighed when prescribing HT.

The Effect of Raloxifene Treatment on Lipid Profile in Elderly Individuals: A Systematic Review and Meta-analysis of Randomized Clinical Trials

PURPOSE

To perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to elucidate the effects of raloxifene on the lipid profile in elderly individuals.

METHODS

A systematic review and meta-analysis of RCTs was performed following the PRISMA statement. Data on triglycerides (TGs), total cholesterol (TC), HDL-C, and LDL-C were extracted. Relevant publications up to October 2020 were detected through searches in the PubMed/MEDLINE, Web of Science, Scopus, and Embase databases. Changes were reported as weighted mean differences (WMDs) and 95% CIs using random-effects models.

FINDINGS

Nine studies were selected, with a duration of intervention ranging from 2 and 12 months and a raloxifene dose of 60 to 120 mg/d. Studies were performed in healthy individuals and in those with disorders, such as osteoporosis, type 2 diabetes, and kidney disease required long-term hemodialysis. Overall, TG (WMD, -6.50 mg/dL; 95% CI, -34.18 to 21.20 mg/eL; P = 0.646), LDL-C (WMD, -17.86 mg/dL; 95% CI, -42.44 to 6.72 mg/dL; P = 0.154), and HDL-C (WMD, 2.35 mg/dL; 95% CI, -1.14 to 5.84 mg/dL; P = 0.187) levels did not change significantly after the administration of raloxifene. In contrast, TC levels decreased after raloxifene therapy (WMD, -6.59 mg/dL; 95% CI, -13.13 to -0.05 mg/dL; P = 0.048).

IMPLICATIONS

Raloxifene therapy decreased TC levels but did not alter TG, HDL-C, and LDL-C concentrations in elderly individuals. Regarding the LDL-C levels, although the finding lacked statistical significance, we believe that there was a mean reduction that deserves further clinical attention as much as TC.

Repurposing the estrogen receptor modulator raloxifene to treat SARS-CoV-2 infection

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) necessitates strategies to identify prophylactic and therapeutic drug candidates to enter rapid clinical development. This is particularly true, given the uncertainty about the endurance of the immune memory induced by both previous infections or vaccines, and given the fact that the eradication of SARS-CoV-2 might be challenging to reach, given the attack rate of the virus, which would require unusually high protection by a vaccine. Here, we show how raloxifene, a selective estrogen receptor modulator with anti-inflammatory and antiviral properties, emerges as an attractive candidate entering clinical trials to test its efficacy in early-stage treatment COVID-19 patients.

Assessment of Cardiovascular Safety of Anti-Osteoporosis Drugs

The incidence of osteoporosis and cardiovascular disease increases with age, and there are potentially shared mechanistic associations between the two conditions. It is therefore highly relevant to understand the cardiovascular implications of osteoporosis medications. These are presented in this narrative review. Calcium supplementation could theoretically cause atheroma formation via calcium deposition, and in one study was found to be associated with myocardial infarction, but this has not been replicated. Vitamin D supplementation has been extensively investigated for cardiac benefit, but no consistent effect has been found. Despite findings in the early 21st century that menopausal hormone therapy was associated with coronary artery disease and venous thromboembolism (VTE), this therapy is now thought to be potentially safe (from a cardiac perspective) if started within the first 10 years of the menopause. Selective estrogen receptor modulators (SERMs) are associated with increased risk of VTE and may be related to fatal strokes (a subset of total strokes). Bisphosphonates could theoretically provide protection against atheroma. However, data from randomised trials and observational studies have neither robustly supported this nor consistently demonstrated the potential association with atrial fibrillation. Denosumab does not appear to be associated with cardiovascular disease and, although parathyroid hormone analogues are associated with palpitations and dizziness, no association with a defined cardiovascular pathology has been demonstrated. Finally, romosozumab has been shown to have a possible cardiovascular signal, and therefore post-market surveillance of this therapy will be vital.

Correlation between soluble receptor for advanced glycation end products levels and coronary artery disease in postmenopausal nondiabetic women

BACKGROUND

The established cardiovascular risk factors cannot explain the overall risk of coronary artery disease (CAD), especially in women. Therefore, there is a growing need for the assessment of novel biomarkers to identify women at risk. The receptor for advanced glycation end products (RAGE) and its interaction with the advanced glycation end product (AGE) ligand have been associated with atherogenesis. The soluble fraction of RAGE (sRAGE) antagonizes RAGE signaling and exerts an antiatherogenic effect.

AIM

The study aim was to explore the association between plasma levels of sRAGE and CAD in nondiabetic postmenopausal women.

METHODS

This case-control study included 110 nondiabetic postmenopausal women who were enrolled in two groups. Group I included 55 angiographically proven CAD subjects with > 50% stenosis in at least one of the major coronary arteries and Group II included 55 healthy control women who did not have CAD or had < 50% stenosis of the coronary arteries. Stenosis was confirmed by invasive angiography. Plasma sRAGE was determined by an enzyme-linked immunosorbent assay.

RESULTS

We observed significantly lower plasma sRAGE concentrations in subjects with CAD vs healthy controls (P < 0.05). Univariate and multivariate logistic regression analysis also revealed a significant correlation between plasma sRAGE levels and CAD (P = 0.01). Multivariate odds ratios for CAD revealed that subjects with sRAGE concentrations below 225 pg/mL (lowest quartile) had a 6-fold increase in CAD prevalence independent of other risk factors.

CONCLUSION

Our findings indicated that low sRAGE levels were independently associated with CAD in nondiabetic postmenopausal women. Risk assessment of CAD in postmenopausal women can be improved by including sRAGE along with other risk factors.

The effect of tibolone treatment on lipid profile in women: A systematic review and dose-response meta-analysis of randomized controlled trials

Inconsistencies exist with regard to influence of tibolone treatment on the lipid profile. The reasons for these inconsistencies might derive from several factors, i.e., differences in baseline variables, intervention duration, participants' health status or baseline body mass index (BMI). To address these inconsistencies, based on a systematic search in Scopus, PubMed/Medline, Web of Science, and Embase for papers published until 21 December 2020, we conducted the current dose-response meta-analysis of randomized controlled trials (RCTs) to determine the impact of tibolone treatment on the lipid profile. The overall findings were derived from 26 RCTs. Tibolone administration decreased total cholesterol (TC) (weighted mean difference, WMD: -18.55 mg/dL, CI: -25.95 to -11.16, P < 0.001), high-density lipoprotein-cholesterol (HDL-C) (WMD: -9.42 mg/dL, CI: -11.83 to -7.01, P < 0.001) and triglyceride (TG) (WMD: -21.43 mg/dL, CI: -27.15 to -15.70, P < 0.001) levels. A significant reduction in LDL-C occurred when tibolone was prescribed for ≤ 26 weeks (WMD: -7.64 mg/dL, 95% CI: -14.58 to -0.70, P = 0.031) versus > 26 weeks (WMD: -8.84 mg/dL, 95% CI: -29.98, 12.29, P = 0.412). The decrease in TG (WMD: -22.64 mg/dL) and TC (-18.55 mg/dL) concentrations was more pronounced in patients with BMI ≥ 25 kg/m²versus BMI < 25 kg/m². This systematic review and meta-analysis discovered that tibolone decreases TC, HDL-C and TG levels. LDL-C concentrations are significantly reduced when tibolone administration lasts for ≤ 26 weeks.

Green Nanotechnology in the Formulation of a Novel Solid Dispersed Multilayered Core-Sheath Raloxifene-Loaded Nanofibrous Buccal Film; In Vitro and In Vivo Characterization

Green nanotechnology utilizes the principles of green chemistry to formulate eco-friendly nanocarrier systems to mitigate patients and environment hazards. Raloxifene (RLX) demonstrates poor aqueous solubility (BCS class II) and low bioavailability, only 2% (extensive first-pass metabolism). The aim of this study is to enhance RLX solubility and bioavailability via development of novel solid dispersed multilayered core-sheath RLX-loaded nanofibers (RLX-NFs) without the involvement of organic solvents. A modified emulsion electrospinning technique was developed. Electrospinning of an RLX-nanoemulsion (RLX-NE) with polymer solution (poly vinyl alcohol (PVA), hydroxypropyl methylcellulose (HPMC), and chitosan (CS) in different volume ratios (1:9, 2:8, and 4:6) using D-optimal response surface methodology was adopted. In vitro characterization of RLX-loaded NFs was performed; scanning electron microscope (SEM), thermal analysis, drug content, release studies, and bioadhesion potential. The optimum NFs formula was evaluated for morphology using high-resolution transmission electron microscopy (HRTEM), and ex vivo drug permeation. The superiority of E2 (comprising RLX-NE and PVA (2:8)) over other NF formulae was statistically observed with respect to Q60 (56.048%), Q240 (94.612%), fiber size (594.678 nm), mucoadhesion time 24 h, flux (5.51 µg/cm2/h), and enhancement ratio (2.12). RLX pharmacokinetics parameters were evaluated in rabbits following buccal application of NF formula E2, relative to RLX oral dispersion. E2 showed significantly higher Cmax (53.18 ± 4.56 ng/mL), and relative bioavailability (≈2.29-fold).

Association between HDL-C levels and menopause: a meta-analysis

PURPOSE

Menopause modifies women's lipid profiles. However, the fact that it is still unclear whether high-density lipoprotein-cholesterol (HDL-C) levels decrease in postmenopausal women necessitated a systematic review and meta-analysis.

METHODS

The PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched and 498 articles published between 1987 and 2020 were retrieved. Studies reporting HDL-C, low-density lipoprotein-cholesterol (LDL-C), total cholesterol (TC), and triglyceride (TG) levels in both postmenopausal and premenopausal populations were included. The quality of the included studies was assessed using the Cross-Sectional/Prevalence Study Quality tool. The standard mean difference (SMD) and 95% confidence interval (CI) were estimated using random effects models. A meta-regression analysis and subgroup analysis were performed to identify potential modifiers. Egger's test and funnel plots were constructed to evaluate publication biases.

RESULTS

Lipid profiles from 18 cross-sectional studies and two cohort studies including 5652 postmenopausal women and 7825 premenopausal women were meta-analyzed. HDL-C levels were not significantly different between the postmenopausal and premenopausal women (SMD = - 0.053, 95% CI - 0.171 to 0.066, p = 0.383) and were not affected by country, publication year, study quality in the meta-regression analysis, or significant publication bias. Higher LDL-C, TC, and TG levels were detected in postmenopausal women than in premenopausal controls.

CONCLUSION

Unlike increased LDL-C, TC, and TG levels, HDL-C levels in pre- and postmenopausal women were not different in this first meta-analysis of lipid profiles in premenopausal and postmenopausal women. Prospective studies with large populations examining HDL-C levels and functions in women with different menopausal statuses are essential in the future.

TRIAL REGISTRATION NUMBER

None.

Raloxifene has favorable effects on the lipid profile in women explaining its beneficial effect on cardiovascular risk: A meta-analysis of randomized controlled trials

There is robust evidence that the appropriate treatment of dyslipidaemia substantially reduces cardiovascular disease-related morbidity and mortality. Raloxifene is a selective oestrogen receptor modulator that also interferes with the lipid metabolism and may be of aid in the management of lipid abnormalities in females. Therefore, we conducted a systematic review and meta-analysis of the available randomized clinical trials (RCTs) exploring the effect of raloxifene on the lipid profile in women. The Scopus, Web of Science, PubMed/Medline and EMBASE databases were systematically and independently searched by two assessors from inception until 20 November 2020 without time and language restrictions. The overall findings were generated from 30 eligible RCTs. As compared to controls, raloxifene resulted in a significant elevation of the high-density lipoprotein-cholesterol (HDL-C) (WMD: 2.41 mg/dL, 95% CI: 0.84-3.97, P = 0.003) and a significant reduction of the total cholesterol (TC) (WMD:-14.84 mg/dL, 95% CI: -20.37 to -9.317, P = 0.000) and of the low-density lipoprotein-cholesterol (LDL-C) (WMD: -17 mg/dL, 95% CI: -25.77, -8.22, P = 0.000). In the stratified analysis, a significant decrease of serum triglycerides (TG) (WMD: -22.06 mg/dL) was achieved in the RCTs with a duration of ≤ 26 weeks (WMD -8.70 mg/dL) and with baseline TG concentrations of ≥ 130 mg/dL (WMD: -23.02 mg/dL). In conclusion, raloxifene treatment can increase HDL-C and lower LDL-C and TC. In terms of TG, a significant decrease can be observed if the administration of raloxifene lasts ≤ 26 weeks and if the baseline TG concentrations are ≥ 130 mg/dL.

Estrogen Receptors: Therapeutic Perspectives for the Treatment of Cardiac Dysfunction after Myocardial Infarction

Estrogen receptors (ER) mediate functions beyond their endocrine roles, as modulation of cardiovascular, renal, and immune systems through anti-inflammatory and anti-apoptotic effects, preventing necrosis of cardiomyocytes and endothelial cells, and attenuating cardiac hypertrophy. Estradiol (E2) prevents cardiac dysfunction, increases nitric oxide synthesis, and reduces the proliferation of vascular cells, yielding protective effects, regardless of gender. Such actions are mediated by ER (ER-alpha (ERα), ER-beta (ERβ), or G protein-coupled ER (GPER)) through genomic or non-genomic pathways, which regulate cardiovascular function and prevent tissue remodeling. Despite the extensive knowledge on the cardioprotective effects of estrogen, clinical studies conducted on myocardial infarction (MI) and cardiovascular diseases still include favorable and unfavorable profiles. The purpose of this review is to provide up-to-date information regarding molecular, preclinical, and clinical aspects of cardiovascular E2 effects and ER modulation as a potential therapeutic target for the treatment of MI-induced cardiac dysfunction.

The Critical Period for Neuroprotection by Estrogen Replacement Therapy and the Potential Underlying Mechanisms

17β-Estradiol (estradiol or E2) is a steroid hormone that has been broadly applied as a neuroprotective therapy for a variety of neurodegenerative and cerebrovascular disorders such as ischemic stroke, Alzheimer's disease, and Parkinson's disease. Several laboratory and clinical studies have reported that Estrogen Replacement Therapy (ERT) had no effect against these diseases in elderly postmenopausal women, and at worst, increased their risk of onset and mortality. This review focuses on the growing body of data from in vitro and animal models characterizing the potential underlying mechanisms and signaling pathways that govern successful neuroprotection by ERT, including the roles of E2 receptors in mediating neuroprotection, E2 genomic regulation of apoptosis- related pathways, membrane-bound receptor-mediated non-genomic signaling pathways, and the antioxidant mechanisms of E2. Also discussed is the current evidence for a critical period of effective treatment with estrogen following natural or surgical menopause and the outcomes of E2 administration within an advantageous time period. The known mechanisms governing the duration of the critical period include depletion of E2 receptors, the switch to a ketogenic metabolic profile by neuronal mitochondria, and a decrease in acetylcholine that accompanies E2 deficiency. Also the major clinical trials and observational studies concerning postmenopausal Hormone Therapy (HT) are summarized to compare their outcomes with respect to neurological disease and discuss their relevance to the critical period hypothesis. Finally, potential controversies and future directions for this field are discussed throughout the review.

The Beneficial and Adverse Effects of Raloxifene in Menopausal Women: A Mini Review

Objectives

The present mini review aimed to summarize the existing knowledge regarding the beneficial and adverse effects of raloxifene in menopausal women.

Methods

This study is a review of relevant publications about the effects of raloxifene on sleep disorder, depression, venous thromboembolism, the plasma concentration of lipoprotein, breast cancer, and cognitive function among menopausal women.

Results

Raloxifene showed no significant effect on depression and sleep disorder. Verbal memory improved with administration of 60 mg/day of raloxifene while a mild cognitive impairment risk reduction by 33% was observed with administration of 120 mg/day of raloxifene. Raloxifene was associated with a 50% decrease in the need for prolapse surgery. The result of a meta-analysis showed a significant decline in the plasma concentration of lipoprotein in the raloxifene group compared to placebo (standardized mean difference, −0.43; 10 trials). A network meta-analysis showed that raloxifene significantly decreased the risk of breast cancer (relative risk, 0.572; 95% confidence interval, 0.327–0.881; P = 0.01). In terms of adverse effects of raloxifene, the odds ratio (OR) was observed to be 1.54 (P = 0.006), indicating 54% increase in the risk of deep vein thrombosis (DVT) while the OR for pulmonary embolism (PE) was 1.05, suggesting a 91% increase in the risk of PE alone (P = 0.03).

Conclusions

Raloxifene had no significant effect on depression and sleep disorder but decreased the concentration of lipoprotein. Raloxifene administration was associated with an increased risk of DVT and PE and a decreased risk of breast cancer and pelvic organ prolapse in postmenopausal women.

Ospemifene's effects on lipids and coagulation factors: a post hoc analysis of phase 2 and 3 clinical trial data

Objective:

To evaluate the effect of ospemifene 60 mg on the lipid and coagulation parameters of postmenopausal women using data from five phase 2 and 3 clinical trials.

Methods:

Data for lipids and coagulation factors for 2,166 postmenopausal women were pooled from five randomized, placebo-controlled studies. Lipid and coagulation parameters included in this analysis were total cholesterol, high-density lipoproteins (HDL), low-density lipoproteins (LDL), triglycerides, activated partial thromboplastin time (aPTT), fibrinogen, antithrombin antigen, protein C Ag, and protein S Ag free.

Results:

Mean percent changes in HDL and LDL were significantly greater with ospemifene versus placebo at month 3 (HDL: 4.4% vs 0.2%; LDL: −5.2% vs 2.4%), month 6 (HDL: 5.1% vs 1.5%; LDL: −6.7% vs 2.4%), and month 12 (HDL: 2.3% vs −1.9%; LDL: −7.0% vs −2.1%; P < 0.05, for all comparisons). Ospemifene significantly reduced total cholesterol at 6 months (−1.8% vs 1.6%; P = 0.0345 versus placebo), and changes in triglycerides with ospemifene were similar to placebo at all three time points. In subgroup analyses based on age, body mass index, and baseline triglyceride level, ospemifene increased HDL and decreased LDL, but had no significant effect on total cholesterol and triglycerides relative to placebo. Ospemifene significantly improved fibrinogen and protein C antigen levels relative to placebo at months 3 (−8.7% vs −0.8% and −2.7% vs 0.5%, respectively), 6 (−6.0% vs 6.7% and −3.6 vs 8.0%), and 12 (−8.7% vs 7.3% and −4.5% vs 6.6%; P < 0.01, for all). The levels of all coagulation factors remained within the normal range throughout the studies.

Conclusion:

Ospemifene 60 mg does not have a detrimental effect on lipid and coagulation parameters of postmenopausal women with up to 12 months of use.

Raloxifene Lowers Plasma Lipoprotein(a) Concentrations: a Systematic Review and Meta-analysis of Randomized Placebo-Controlled Trials

BACKGROUND AND AIMS

Lipoprotein(a) (Lp(a)) is a proatherogenic plasma lipoprotein and an independent risk factor for atherosclerotic cardiovascular disease. We investigated the effects of raloxifene, selective estrogen receptor modulator, on circulating Lp(a) levels in postmenopausal women using a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

To identify relevant studies, electronic databases (PUBMED, Scopus, Web of Science, and Google Scholar) were searched by up to May 2015 to find controlled trials exploring the effects of oral raloxifene treatment on plasma Lp(a) levels in postmenopausal women. A random-effects model and generic inverse variance method were used for quantitative data synthesis.

RESULTS

Overall, seven eligible RCTs with ten treatment arms were included in this meta-analysis. Meta-analysis suggested a significant reduction of Lp(a) levels after treatment with raloxifene (standardized mean difference (SMD) -0.42; 95% CI -0.65, -0.19; p < 0.001), which may be considered as a medium effect size. When the studies were categorized according to the administered dose, there was a significant effect in both subsets of studies with administered doses ≤60 mg/day (SMD -0.43; 95% CI -0.73, -0.13; p = 0.004) and >60 mg/day (SMD -0.36; 95% CI -0.68, -0.05; p = 0.025). No significant association between the changes in plasma concentrations of Lp(a) with dose and baseline Lp(a) levels was found in the random-effects meta-regression analysis. However, a significant inverse association was observed between the Lp(a)-lowering effect of raloxifene and duration of treatment (p = 0.001).

CONCLUSIONS

Results of the present meta-analysis showed a reduction in plasma Lp(a) concentrations of postmenopausal women with oral raloxifene treatment.

Does sex matter? Effects on venous thromboembolism risk in screened trauma patients

BACKGROUND

Sex is associated with disparate risk of venous thromboembolism (VTE) in nontrauma patients, with increased risk seen during pregnancy and in women on hormone-containing medications. Sex effects on VTE after trauma are unclear. Some studies have demonstrated no effect whereas others have instead shown a higher incidence of VTE among men. We hypothesized that male sex would increase the risk of VTE across all age groups in trauma patients undergoing standardized duplex screening.

METHODS

All admissions to a Level I academic trauma center 2000 to 2014 were reviewed. We excluded patients for age <18 years, pregnancy, pre-admission anticoagulant use, and hospital length of stay (LOS) <72 hours. A strict venous duplex screening protocol was followed. Female patients were subcategorized into pre- and post-menopausal groups based on age (18-44 vs. ≥ 55 years). Bivariate analysis and logistic regression were used to identify variables correlating with VTE risk.

RESULTS

A total of 8,726 patients met inclusion criteria. The overall VTE rate was 5.3%. Bivariate analysis did not find a difference in VTE risk by sex (5.1% women vs. 5.4% men, p = 0.565), or between women and men within age-defined menopausal categories (pre-menopausal women 3.9% vs. men 4.7%, p = 0.293; post-menopausal women 5.9% vs. men 7.0%, p = 0.22). Logistic regression (see figure) did identify other risk factors for VTE including age ≥55 (adjusted odds ratio [AOR] 2.0), increasing ISS (AOR 1.5-2.1), penetrating mechanism of injury (AOR 2.2), lower extremity injury (AOR 1.7), need for mechanical ventilation (AOR 2.1), and increasing hospital length of stay (LOS 7-28 days, AOR 3.8; LOS > 28 days, AOR 9.1).

CONCLUSION

There was no difference in VTE rates based on patient sex, even after controlling for menopausal status. Aggressive VTE screening of over 8,700 patients did identify several other patient populations at increased risk of developing VTE. More intensive VTE prophylaxis may be appropriate in these patients.

LEVEL OF EVIDENCE

Epidemiologic study, level III; therapeutic study, level V.

Combination Therapy of Raloxifene and Alendronate for Treatment of Osteoporosis in Elderly Women

Objectives

To evaluate and compare the efficacy and safety of the combination of raloxifene and alendronate with those of monotherapies in elderly women with osteoporosis.

Methods

Sixty-two postmenopausal women (mean age 63.5 ± 0.5 years) attending gynecologic osteoporosis clinics with established osteoporosis were randomly allocated to one of four treatment groups and monitored for 3 years. All patients enrolled in this study, including those in the control group (n = 14), received 1.0 g elemental calcium and 400 units of vitamin D per day. The raloxifene group (n = 16) received raloxifene 60 mg (Evista®) per day; alendronate group (n = 17) received low-dose (5 mg) alendronate with calcitriol 0.5 µg (Maxmarvil®) per day; and the combination therapy group (n = 15) received both raloxifene 60 mg and low-dose (5 mg) alendronate with calcitriol 0.5 µg. Bone mineral density (BMD) was measured in the lumbar spine and hip before and after 3 years of treatment.

Results

In patients who received the combined therapy, BMD increased in the lumbar spine and the hip by 7.2% (P<0.001) and 4.8% (P<0.001) at 3 years. For patients in the alendronate group, the increases were 6.7% (P<0.001) and 3.1% (P<0.01) respectively, for the raloxifene group, the increases were 4.36% (P<0.001) and 1.9% (P<0.05) in the vertebrae and femora, respectively; however, the BMD of patients in the control group decreased by 1.81% (P<0.05) and 1.6% (P<0.05), respectively, after 3 years. Patients who received the combination therapy had significantly higher BMD in both the vertebrae femora (P<0.01) in comparison to that in those treated with raloxifene or alendronate individually.

Conclusions

This 3-year randomized study showed the improved effects of alendronate and raloxifene combination on spine and hip BMD in elderly postmenopausal women with established osteoporosis.

Two Decades of Cardiovascular Trials With Primary Surrogate Endpoints: 1990-2011

Background

Surrogate endpoint trials test strategies more efficiently but are accompanied by uncertainty about the relationship between changes in surrogate markers and clinical outcomes.

Methods and Results

We identified cardiovascular trials with primary surrogate endpoints published in the New England Journal of Medicine, Lancet, and JAMA: Journal of the American Medical Association from 1990 to 2011 and determined the trends in publication of surrogate endpoint trials and the success of the trials in meeting their primary endpoints. We tracked for publication of clinical outcome trials on the interventions tested in surrogate trials. We screened 3016 articles and identified 220 surrogate endpoint trials. From the total of 220 surrogate trials, 157 (71.4%) were positive for their primary endpoint. Only 59 (26.8%) surrogate trials had a subsequent clinical outcomes trial. Among these 59 trials, 24 outcomes trial results validated the positive surrogates, whereas 20 subsequent outcome trials were negative following positive results on a surrogate. We identified only 3 examples in which the surrogate trial was negative but a subsequent outcomes trial was conducted and showed benefit. Findings were consistent in a sample cohort of 383 screened articles inclusive of 37 surrogate endpoint trials from 6 other high‐impact journals.

Conclusions

Although cardiovascular surrogate outcomes trials frequently show superiority of the tested intervention, they are infrequently followed by a prominent outcomes trial. When there was a high‐profile clinical outcomes study, nearly half of the positive surrogate trials were not validated. Cardiovascular surrogate outcome trials may be more appropriate for excluding benefit from the patient perspective than for identifying it.

Raloxifene Administration in Women Treated with Long Term Gonadotropin-releasing Hormone Agonist for Severe Endometriosis: Effects on Bone Mineral Density

Objectives

To evaluate the efficacy of raloxifene in preventing bone loss associated with long term gonadotropin-releasing hormone agonist (GnRH-a) administration.

Methods

Twenty-two premenopausal women with severe endometriosis were treated with leuprolide acetate depot at a dosage of 3.75 mg/4 weeks, for 48 weeks. Bone mineral density (BMD) was evaluated at admission, and after 12 treatment cycles.

Results

At cycle 12 of GnRH-a plus raloxifene treatment, lumbar spine, trochanter femoral neck, and Ward's BMD differed from before the treatment. A year after treatment, the lumbar spine and trochanter decreased slightly, but were not significantly different.

Conclusions

Our study shows that the administration of GnRH-a plus raloxifene in pre-menopausal women with severe endometriosis, is an effective long-term treatment to prevent bone loss.

Raloxifene: A Selective Estrogen Receptor Modulator for Reducing the Risk of Invasive Breast Cancer in Postmenopausal Women

Raloxifene hydrochloride is a selective estrogen receptor modulator that has antiestrogenic effects on breast and endometrial tissue and estrogenic effects on bone, lipid metabolism and blood clotting. Tamoxifen is the prototypical selective estrogen receptor modulator and reduces the risk of both in situ and invasive breast cancers by half when compared with placebo. The limitations on the use of tamoxifen for breast cancer risk reduction relate to its well-known, but rare, side effects. A number of clinical trials have established the benefit of raloxifene on osteoporosis and fracture. Raloxifene significantly improves serum lipids and serum markers of cardiovascular disease risk, but has no significant effect on the risk of primary coronary events. In several osteoporosis trials and the Raloxifene Use for The Heart (RUTH) trial, raloxifene decreased the risk of estrogen receptor-positive breast cancer by 44–90%. In the Study of Tamoxifen And Raloxifene (STAR) trial, the effect of raloxifene on invasive breast cancer was equivalent to that of tamoxifen, with more favorable effects on uterine malignancy and clotting events. Symptomatic side effects are acceptable. In total, the available data indicate that raloxifene represents an acceptable alternative to tamoxifen for the reduction of the risk of postmenopausal breast cancer in high-risk women. The potential market for a compound shown to reduce the risk of breast cancer in postmenopausal women who are at increased risk for breast cancer is more than 10 million women in the USA alone.

Unintended positive and negative effects of drugs on lipoproteins

PURPOSE OF REVIEW

Dyslipidaemia is an important cardiovascular disease risk factor. Many drugs affect lipid profile and lipoprotein metabolism. We reviewed unintended effects of nonlipid modifying, commonly used medications on lipid profile and lipoprotein metabolism.

RECENT FINDING

Several detrimental effects of many drug classes such as diuretics, antidepressant, anticonvulsant and antiretroviral drugs have been reported, whereas other drug classes such as antiobesity, alpha 1-blockers, oestrogens and thyroid replacement therapy were associated with positive effects.

SUMMARY

Dyslipidaemia is a common side-effect of many medications. This should be taken into consideration, especially in patients at high risk of cardiovascular disease. Other drugs demonstrated positive effects on circulating lipids and lipoproteins. The impact of these unintended effects on atherosclerotic disease risk and progression is unclear.

Effects of LY117018 (a SERM analog of raloxifene) on tumor suppressor proteins and proliferation of breast cancer cells

We have previously shown that presence of estradiol (E2) in the growth medium causes (i) proliferation of T47D breast cancer cells, (ii) elevation of p53 levels, and (iii) hyperphos-phorylation of retinoblastoma protein (pRb). In the present study, we examined the expression of p53, phosphorylation state of pRb and proliferation of T47D cells in the presence of LY117018 (Courtesy of Lilly Research Laboratories), an analog of raloxifene, which is a known selective estrogen receptor modulator (SERM). The cells grown in charcoal-treated serum were treated with 1 nM E2 or different concentrations of LY117018 for 24 h. E2 or LY117018 treatments caused a 2- to 3-fold increase in the level of p53 and hyperphosphorylation of pRb. E2 treatment increased cell proliferation, whereas LY117018 treatment had no such effect but inhibited the E2-dependent cell proliferation. E2 and LY117018 treatments of T47D cells also caused differential effects on intracellular structures. Thus, LY117018 treatment induces changes in the level/activity of p53 and pRb and ultrastructure of T47D cells. Importantly, LY11708 inhibits estrogen-induced cell proliferation while mimicking E2 actions on p53 induction and pRb phosphorylation. The SERM also induced structural alterations in the T47D cells.

Effect of raloxifene hydrochloride on bone mineral density and bone turnover in Kuwaiti postmenopausal women with osteoporosis

SUMMARY

Osteoporosis is a major cause of mortality and morbidity worldwide. Decreased bone turnover markers and increased lumbar spine and total hip bone mineral density (BMD) in raloxifene-treated women add further support to the idea that raloxifene is an effective well-tolerated option for treating Kuwaiti postmenopausal osteoporosis, suitable for long-term use.

INTRODUCTION/PURPOSE

Osteoporosis is currently a major cause of mortality, morbidity, and medical expense worldwide, and it is important to investigate therapies for the prevention and treatment of osteoporosis in postmenopausal women. This study was designed to detect the effect of raloxifene hydrochloride on bone mineral density and bone turnover in Kuwaiti postmenopausal women with osteoporosis.

METHODS

Postmenopausal women who were free of severe or chronically disabling conditions, had their last menstrual period at least 2 years before the beginning of the study, had a T score for femoral neck or lumbar spine BMD measurements ≤2.5, and were without fractures were included in this study. One hundred and seventy-six (176) women were included in this study and were divided into two groups; the first group (study) received raloxifene with calcium and vitamin D daily for 12 months, and the second group (control) received only calcium and vitamin D. BMD and bone metabolism markers were measured before and after treatment.

RESULTS

One year after treatment, BMD of lumbar spine and total hip was significantly increased in study group (3.21 ± 5.4 and 1.62 ± 7.4, respectively) compared to controls (0.9 ± 3.8 and -0.8 ± 5.6, respectively); also, Ward's triangle and trochanter BMD was significantly increased in study group (4.84 ± 9.3 and 1.78 ± 8.5, respectively) compared to controls (1.53 ± 6.6 and -1. 4 ± 6.4, respectively). C-telopeptide was significantly decreased in study group (121 ± 7.8) compared to control group (1,480 ± 6.3); also, serum osteocalcin was significantly decreased in study group (14.5 ± 8.3) compared to control group (43.8 ± 1.3) 1 year after treatment. Occurrence of fractures during this study was significantly low in raloxifene group compared to controls (0 (0%) versus 3 (3.6%), respectively).

CONCLUSIONS

Raloxifene appears to be an effective, well-tolerated option for treating osteoporosis in Kuwaiti postmenopausal women, suitable for long-term use.

Inverse correlation of carotid intima-media thickness with raloxifene serum levels in osteoporosis

BACKGROUND

Raloxifene is a selective oestrogen receptor modulator with effects on bone and breast cancer and cardiovascular disease risk. The aim of this study was to examine the influence of raloxifene treatment on surrogate markers of atherosclerosis and the correlation of these markers with raloxifene serum concentrations.

METHODS

A prospective clinical trial on 53 postmenopausal osteoporotic women treated with raloxifene was performed. Surrogate markers of atherosclerosis (flow-mediated vasodilatation, glyceryltrinitrate-induced vasodilatation of the brachial artery, carotid intima-media thickness (c-IMT), inter-cell adhesion molecule-1, vascular-cell adhesion molecule-1 and E-selectin) were measured before and after 6 months of treatment. Serum concentrations of raloxifene and raloxifene metabolites were assessed after 12 months of treatment. The tested markers were correlated with measured serum concentrations of raloxifene species.

RESULTS

Among the tested surrogate markers of atherosclerosis c-IMT, E-selectin and ICAM changed significantly during treatment. A negative correlation of the non-metabolized raloxifene serum levels with the percentage change of c-IMT during treatment (r = - 0.315, p = 0.048) was found. Likewise, the sum of the levels of three raloxifene metabolites, raloxifene-6-b-glucuronide (M1), raloxifene-4'-b-glucuronide (M2) and raloxifene-6,4'-diglucuronide (M3) in serum showed a negative correlation with the percentage change of c-IMT during treatment (r = - 0.375, p = 0.017). For the other tested parameters, no correlation with raloxifene serum levels was found.

CONCLUSIONS

To the best of our knowledge, this is the first study correlating raloxifene species serum concentrations with changes in the surrogate markers of atherosclerosis. A greater decrease of c-IMT in patients with higher raloxifene concentrations could contribute to a lower risk of cardiovascular events in these patients.

Update on raloxifene: mechanism of action, clinical efficacy, adverse effects, and contraindications

Raloxifene is the only selective estrogen receptor modulator approved for long-term treatment in the prevention of osteoporotic fractures and for the reduction of invasive breast cancer risk in post-menopausal women. The demonstrated beneficial effects on bone and mammalian tissue led clinical and molecular research to focus mainly on these organs, giving less attention to all other systemic effects. The aim of this review was to evaluate all described systemic effects of raloxifene, investigating its molecular and tissutal mechanism of action. A literature research was carried out in electronic databases MEDLINE, EMBASE, ScienceDirect, and the Cochrane Library in interval time between 2000 and 2012. Outcomes were considered in relation to positive/adverse effects concerning bone metabolism, lipid metabolism, coagulation pattern, menopausal symptoms, breast cancer onset, and endometrial cancer onset. Raloxifene acts as an estrogen agonist or antagonist depending on the tissue. This feature is related to specific actions on at least 2 distinct estrogen receptors, whose proportions vary according to tissue type. Raloxifene is a drug for the treatment of osteoporosis and for the prevention of estrogen receptor-positive breast cancer because it guarantees a safety profile on the endometrium. Raloxifene is furthermore an effective therapy in women with increased levels of plasma cholesterol. Raloxifene treatment shifts the coagulation pattern toward prothrombosis, and the patients should be exhaustively informed about the risks associated with therapy. Raloxifene does not show to affect memory and cognition. Finally, it is noteworthy that quality-of-life studies demonstrated some favorable effects of raloxifene.

Epistasis analysis for estrogen metabolic and signaling pathway genes on young ischemic stroke patients

Background

Endogenous estrogens play an important role in the overall cardiocirculatory system. However, there are no studies exploring the hormone metabolism and signaling pathway genes together on ischemic stroke, including sulfotransferase family 1E (SULT1E1), catechol-O-methyl-transferase (COMT), and estrogen receptor α (ESR1).

Methods

A case-control study was conducted on 305 young ischemic stroke subjects aged ≦ 50 years and 309 age-matched healthy controls. SULT1E1 -64G/A, COMT Val158Met, ESR1 c.454−397 T/C and c.454−351 A/G genes were genotyped and compared between cases and controls to identify single nucleotide polymorphisms associated with ischemic stroke susceptibility. Gene-gene interaction effects were analyzed using entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional multiple regression models.

Results

COMT Val158Met polymorphism showed a significant association with susceptibility of young ischemic stroke among females. There was a two-way interaction between SULT1E1 -64G/A and COMT Val158Met in both MDR and CART analysis. The logistic regression model also showed there was a significant interaction effect between SULT1E1 -64G/A and COMT Val158Met on ischemic stroke of the young (P for interaction = 0.0171). We further found that lower estradiol level could increase the risk of young ischemic stroke for those who carry either SULT1E1 or COMT risk genotypes, showing a significant interaction effect (P for interaction = 0.0174).

Conclusions

Our findings support that a significant epistasis effect exists among estrogen metabolic and signaling pathway genes and gene-environment interactions on young ischemic stroke subjects.

Raloxifene: a selective estrogen-receptor modulator for postmenopausal osteoporosis - a clinical update on efficacy and safety

Selective estrogen-receptor modulators are molecules with specific estrogen-receptor binding affinity. Each selective estrogen-receptor modulator induces a unique conformation in the ligand-receptor complex, which leads to transcriptional activation and/or inhibition. Raloxifene 60 mg/day, a benzothiophene selective estrogen-receptor modulator, is approved for the prevention and treatment of postmenopausal osteoporosis. This article provides an update on new studies and further analyses of clinical trial data for raloxifene. The Multiple Outcomes of Raloxifene Evaluation (MORE) trial of women with osteoporosis has described the efficacy of raloxifene in decreasing vertebral fracture risk over 4 years. The Continuing Outcomes Relevant to Evista((R)) (CORE) trial, designed to assess the effects of raloxifene on breast cancer prevention, is a 4-year continuation of MORE. The skeletal and cardiovascular effects of raloxifene in the CORE study were similar to those observed in MORE. The relative risk of developing breast cancer was significantly decreased in women treated with raloxifene, compared with placebo, after 4 years in MORE and 8 years in the CORE trial. The incidence of uterine bleeding, endometrial hyperplasia and endometrial cancer was similar between raloxifene and placebo after 8 years of treatment. Raloxifene use is associated with a higher incidence of hot flashes and leg cramps, and an increased risk of venous thromboembolic events.

RNA therapeutics targeting osteoclast-mediated excessive bone resorption

RNA interference (RNAi) is a sequence-specific post-transcriptional gene silencing technique developed with dramatically increasing utility for both scientific and therapeutic purposes. Short interfering RNA (siRNA) is currently exploited to regulate protein expression relevant to many therapeutic applications, and commonly used as a tool for elucidating disease-associated genes. Osteoporosis and their associated osteoporotic fragility fractures in both men and women are rapidly becoming a global healthcare crisis as average life expectancy increases worldwide. New therapeutics are needed for this increasing patient population. This review describes the diversity of molecular targets suitable for RNAi-based gene knock down in osteoclasts to control osteoclast-mediated excessive bone resorption. We identify strategies for developing targeted siRNA delivery and efficient gene silencing, and describe opportunities and challenges of introducing siRNA as a therapeutic approach to hard and connective tissue disorders.

Research resource: Transcriptional profiling in a cellular model of breast cancer reveals functional and mechanistic differences between clinically relevant SERM and between SERM/estrogen complexes

Exploitation of the relationship between estrogen receptor (ER) structure and activity has led to the development of 1) selective ER modulators (SERM), compounds whose relative agonist/antagonist activities differ between target tissues; 2) selective ER degraders (SERD), compounds that induce a conformational change in the receptor that targets it for proteasomal degradation; and 3) tissue-selective estrogen complexes (TSEC), drugs in which a SERM and an ER agonist are combined to yield a blended activity that results in distinct clinical profiles. In this study, we have performed a comprehensive head-to-head analysis of the transcriptional activity of these different classes of ERM in a cellular model of breast cancer. Not surprisingly, these studies highlighted important functional differences and similarities among the existing SERM, selective ER degraders, and TSEC. Of particular importance was the identification of genes that were regulated by various TSEC combinations but not by an estrogen or SERM alone. Cumulatively, the findings of this analysis are informative with respect to the mechanisms by which ER is engaged by different enhancers/promoters and highlights how promoter context influences the pharmacological activity of ER ligands.

Organic anion transporting polypeptides OATP1B1 and OATP1B3 and their genetic variants influence the pharmacokinetics and pharmacodynamics of raloxifene

Background

Raloxifene, a selective estrogen receptor modulator, exhibits quite large and unexplained interindividual variability in pharmacokinetics and pharmacodynamics. The aim of this study was to determine the role of organic-anion transporting polypeptides OATP1B1 and OATP1B3 and their genetic variants in the pharmacokinetics and pharmacodynamics of raloxifene.

Methods

To test the role of OATP1B1 and OATP1B3 transporters on hepatic uptake of raloxifene and its metabolites an in vitro model of Chinese Hamster Ovary cells expressing OATP1B1 or OATP1B3 was employed. The influence of OATP1B1 and OATP1B3 genetic variants on in vivo pharmacokinetics and pharmacodynamics was evaluated in 53 osteoporotic postmenopausal women treated with raloxifene.

Results

Our in vitro results showed that raloxifene and two of the three metabolites, raloxifene-4'-β-glucuronide (M2) and raloxifene-6,4'-diglucuronide (M3), interact with OATP1B1 and OATP1B3. Higher M3 and total raloxifene serum concentrations in patients correlated with lower serum levels of bone resorption marker, serum C-terminal telopeptide fragments of type I collagen, indicating a higher antiresorptive effect of raloxifene. Higher concentrations of M2 correlated with higher increase of lumbar spine bone mineral density supporting the raloxifene vertebral fracture specific protection effect. Finally, raloxifene, M3 and total raloxifene serum concentrations were significantly higher in patients with SLCO1B1 c.388A > G polymorphism and *1b haplotype implicating a considerable genetic effect on pharmacokinetics and pharmacodynamics of raloxifene.

Conclusions

These findings indicate that SLCO1B1 c.388A > G polymorphism could play an important role in pharmacokinetics and pharmacodynamics of raloxifene.

Selective estrogen receptor modulation in pancreatic β-cells and the prevention of type 2 diabetes

We recently showed that the female hormone 17β-estradiol (E2) protects against β-cell failure in rodent models of type 2 diabetes (T2D) by suppressing islet fatty acids and glycerolipids synthesis, thus preventing lipotoxic β-cell failure. E2 anti-lipogenic actions were recapitulated by pharmacological activation of the estrogen receptor (ER)α, ERβ and the G-protein coupled ER (GPER) in cultured rodent and human β-cells. In vivo, in mouse islets, ERα activation inhibited β-cell lipogenesis by suppressing fatty acid synthase expression (and activity) via an extranuclear, estrogen response element (ERE)-independent pathway requiring the signal transducer and activator of transcription 3. Here, we show that in INS-1 insulin-secreting cells, the selective ER modulator (SERM), Raloxifene, behaves both as ER antagonist with regard to nuclear ERE-dependent actions and as an ER agonist with regard to suppressing triglyceride accumulation. This additional finding opens the perspective that SERMs harboring ER agonistic activity in β-cells could have application in postmenopausal prevention of T2D. Additional studies using novel generation SERMs are needed to address this issue.

Sex hormones, aging, and Alzheimer's disease

A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.

Sex hormones, aging, and Alzheimer's disease

A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.

Black cohosh (Cimicifuga racemosa) relaxes the isolated rat thoracic aorta through endothelium-dependent and -independent mechanisms

AIM OF THE STUDY

The rhizome of the Cimicifuga racemosa (commonly known as black cohosh) has been used in treatment of climacteric complaints for decades in North America and Europe. A number of studies investigated the estrogenic potential of black cohosh, but its effectiveness is still controversial. Recently, it was reported that the extract of black cohosh acted as an agonist at the serotonin (5-HT) receptor and 5-HT derivative was isolated out of the black cohosh extract. Because it is well known that the 5-HT elicited the various cardiovascular effects including vasorelaxation, we investigated the vasorelaxant effects of the extract of black cohosh and its possible mechanisms of action.

MATERIALS AND METHODS

The extract of black cohosh (BcEx) was examined for its vasorelaxant effects in isolated rat aorta. The aortic rings were equilibrated under resting tension and induced reproducible contraction in organ bath. The control contraction was produced by 300 nM NE, and then BcEx were added. In experiments where specific inhibitors were used, they were added 20 min before NE contraction.

RESULTS

BcEx elicited two phases of relaxation in rat aorta pre-contracted with norepinephrine. The first, a rapid relaxation, which occurred within seconds of BcEx administration, was eliminated by pretreatment with N(G)-nitro-l-arginine (l-NNA) or methylene blue. The endogenous NO synthase substrate l-Arg markedly reversed the action of l-NNA, indicating that BcEx elicited the vasorelaxant effect via the NO/cGMP pathway. The second, slowly developing relaxation was not affected by the endothelium denudation. BcEx-induced endothelium-independent vasorelaxation appears to involve the inhibition of calcium influx mediated by the opening of inward rectifier potassium channels.

CONCLUSIONS

BcEx elicits the vasorelaxant effect via endothelium-dependent and -independent mechanisms and may contribute to a better understanding of a potential link between the use of black cohosh and its beneficial effects on vascular health.