phytoestrogens and Atherosclerosis

Hypercholesterolemia is a predominant risk factor for atherosclerosis and associated coronary and cerebrovascular diseases. Control of cholesterol levels through therapeutic drugs, notably statins, have significantly reduced the risk for developing atherosclerosis and associated cardiovascular diseases. However, adverse effects associated with therapeutic drugs warrant to find other alternative approaches for managing hypercholesterolemia, especially for those with borderline cholesterol levels. Food supplements have increasingly become attractive alternatives to prevent or treat hypercholesterolemia and reduce the risk for cardiovascular diseases. This review summarized current patents on food supplements with claims of hypocholesterolemic effects. They can be mainly divided into four categories based on the active ingredients in the supplements: 1) plant sterols or stanols; 2) fiber or polysaccharides; 3) microorganism-derived; and 4) soy protein and phytoestrogens. The efficacy, mechanisms of action and potential side effects are reviewed for each of the four categories. The hypocholesterolemic effects of plant sterols, fiber, Monascus products and soy protein preparations have been consistently demonstrated in clinical trails whereas the efficacy of some probiotic bacteria and phytoestrogens-containing supplements remains to be established. Accumulative clinical data show that plant sterols, fiber, soy protein and phytoestrogen are generally considered safe and cause no obvious side effects. However, additional clinical studies are required to establish the safety profiles of certain probiotic bacteria as food supplements.

Topics: Anticholesteremic Agents; Atherosclerosis; Bile Acids and Salts; Dietary Fiber; Humans; Hypercholesterolemia; Lipoproteins, HDL; Lipoproteins, LDL; Monascus; Phytoestrogens; Phytosterols; Polysaccharides; Probiotics; Sitosterols; Soybean Proteins

Dietary isoflavones are currently receiving much attention because of their potential role in preventing coronary artery disease and other chronic diseases. Accumulating evidence from cell culture and laboratory animal experiments indicates that isoflavones have the potential to prevent or delay atherogenesis. Suggested mechanisms of action include: a reduction in low-density lipoprotein (LDL) cholesterol and a potential reduction in the susceptibility of the LDL particle to oxidation; (2) an improvement in vascular reactivity; (3) an inhibition of pro-inflammatory cytokines, cell adhesion proteins and nitric oxide (NO) production; and (4) an inhibition of platelet aggregation. These mechanisms are consistent with the epidemiological evidence that a high consumption of isoflavone-rich soy products is associated with a reduced incidence of coronary artery disease. Biological effects of isoflavones are dependent on many factors, including dose consumed, duration of use, protein-binding affinity, and an individual's metabolism or intrinsic oestrogenic state. Further clinical studies are necessary to determine the potential health effects of isoflavones in specific population groups as we currently know little about age-related differences in exposure to these compounds and there are few guidelines on optimal dose for cardiovascular health benefits.

Topics: Animals; Atherosclerosis; Coronary Disease; Diet; Female; Humans; Isoflavones; Lipids; Male; Phytoestrogens; Receptors, Estrogen; Tissue Distribution

The present study evaluated the risks and benefits of phytoestrogen treatment in healthy perimenopausal women in relation to the dynamics of climacteric syndrome and progression of atherosclerosis. Study participants were treated with placebo or phytoestrogen-rich natural preparation Karinat based on grape (Vitis vinifera) seeds, green tea (Camellia sinensis) leaves, hop (Hunulus lupulus) cone powder and garlic (Allium sativum) powder. The dynamics of climacteric syndrome was evaluated by Kupperman Index and Utian Quality of Life Scale. Atherosclerosis progression was evaluated by measuring carotid intima-media thickness. Significant changes of climacteric syndrome's severity in both Karinat and placebo groups (p = 0.005 and p = 0.001) were obtained after 24 months of follow-up. Detailed analysis of Kupperman Index suggested that Karinat possessed a significant effect on nervousness (p = 0.010), weakness (p = 0.020) and formication (p = 0.010). A significant improvement of medical (p = 0.070) and emotional (p = 0.060) components of Kupperman Index and Utian Quality of Life Scale was also observed in Karinat group. However, difference in carotid intima-media thickness between the two groups was not statistically significant at follow-up. A slight positive effect of phytoestrogens on climacteric syndrome manifestations was demonstrated in this study. Karinat can be used for alleviation of climacteric syndrome and cardiovascular disease prevention in perimenopausal women. Copyright © 2017 John Wiley & Sons, Ltd.

Topics: Adult; alpha-Tocopherol; Ascorbic Acid; Atherosclerosis; beta Carotene; Carotid Intima-Media Thickness; Double-Blind Method; Female; Humans; Middle Aged; Perimenopause; Phytoestrogens; Phytotherapy; Quality of Life

The risk of cardiovascular disease and atherosclerosis progression is significantly increased after menopause, probably due to the decrease of estrogen levels. The use of hormone replacement therapy (HRT) for prevention of cardiovascular disease in older postmenopausal failed to meet expectations. Phytoestrogens may induce some improvements in climacteric symptoms, but their effect on the progression of atherosclerosis remains unclear. The reduction of cholesterol accumulation at the cellular level should lead to inhibition of the atherosclerotic process in the arterial wall. The inhibition of intracellular lipid deposition with isoflavonoids was suggested as the effective way for the prevention of plaque formation in the arterial wall. The aim of this double-blind, placebo-controlled clinical study was to investigate the effect of an isoflavonoid-rich herbal preparation on atherosclerosis progression in postmenopausal women free of overt cardiovascular disease. One hundred fifty-seven healthy postmenopausal women (age 65 ± 6) were randomized to a 500 mg isoflavonoid-rich herbal preparation containing tannins from grape seeds, green tea leaves, hop cone powder, and garlic powder, or placebo. Conventional cardiovascular risk factors and intima-media thickness of common carotid arteries (cIMT) were evaluated at the baseline and after 12 months of treatment. After 12-months follow-up, total cholesterol decreased by 6.3% in isoflavonoid-rich herbal preparation recipients (p = 0.011) and by 5.2% in placebo recipients (p = 0.020); low density lipoprotein (LDL) cholesterol decreased by 7.6% in isoflavonoid-rich herbal preparation recipients (p = 0.040) and by 5.2% in placebo recipients (non-significant, NS); high density lipoprotein (HDL) cholesterol decreased by 3.4% in isoflavonoid-rich herbal preparation recipients (NS) and by 4.5% in placebo recipients (p = 0.038); triglycerides decreased by 6.0% in isoflavonoid-rich herbal preparation recipients (NS) and by 7.1% in placebo recipients (NS). The differences between lipid changes in the isoflavonoid-rich herbal preparation and placebo recipients did not reach statistical significance (p > 0.05). Nevertheless, the mean cIMT progression was significantly lower in isoflavonoid-rich herbal preparation recipients as compared to the placebo group (6 μm, or <1%, versus 100 μm, or 13%; p < 0.001 for the difference). The growth of existing atherosclerotic plaques in isoflavonoid-rich herbal preparation recipients was i

Topics: Aged; Atherosclerosis; Cardiovascular Diseases; Double-Blind Method; Female; Humans; Isoflavones; Middle Aged; Phytoestrogens; Plant Preparations; Postmenopause; Triglycerides

The aim of this study was to investigate the effects of pure genistein therapy on asymmetric dimethylarginine in healthy postmenopausal women. Healthy postmenopausal women received pure genistein (n=21) or placebo (n=17) for 6 months, and no statistically significant effects on plasma asymmetric dimethylarginine levels were found with pure genistein treatment.

Topics: Adult; Arginine; Atherosclerosis; Female; Genistein; Humans; Middle Aged; Phytoestrogens; Placebos; Postmenopause; Reference Values; Risk Factors

Estrogen receptor α (ERα) is a ligand-activated transcriptional activator that is also involved vascular inflammation and atherosclerosis. Whether different ligands may affect this activity has not been explored. We screened a panel of phytoestrogens for their role in ERα binding and transcriptional transcription, and correlated the findings to anti-inflammatory activities in vascular endothelial cells stably expressing either a wild-type or mutant form of ERα deficient in its membrane association. Taxifolin and silymarin were "high binders" for ERα ligand binding; quercetin and curcumin were "high activators" for ERα transactivation. Using these phytoestrogens as functional probes, we found, in endothelial cells expressing wild-type ERα, the ERα high activator, but not the ERα high binder, promoted ERα nuclear translocation, estrogen response element (ERE) reporter activity, and the downstream gene expression. In endothelial cells expressing membrane association-deficient mutant ERα, the ERα nuclear translocation was significantly enhanced by taxifolin and silymarin, which still failed to activate ERα. Inflammation response was examined using the systemic or vascular inflammation inducers lipopolysaccharide or oxidized low-density lipoprotein. In both cases, only the ERα high activator inhibited nuclear translocation of nuclear factor κB, JNK, and p38, and the production of inflammatory cytokines IL-1β and TNFα. We confirm a threshold nuclear accumulation of ERα is necessary for its transactivation. The anti-inflammatory activity of phytoestrogens is highly dependent on ERα transactivation, less so on the ligand binding, and independent of its membrane association. A pre-examination of phytoestrogens for their mode of ERα interaction could facilitate their development as better targeted receptor modifiers.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Atherosclerosis; Cell Line; Curcumin; Endothelial Cells; Estrogen Receptor alpha; Humans; Inflammation; Interleukin-1beta; Ligands; Lipopolysaccharides; Lipoproteins, LDL; MAP Kinase Kinase 4; Molecular Docking Simulation; Mutation; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Phytoestrogens; Protein Transport; Quercetin; Response Elements; Signal Transduction; Silymarin; Tumor Necrosis Factor-alpha

The development of atherosclerosis is closely related to excessive endoplasmic reticulum stress (ERs). Equol reportedly protects against cardiovascular disease; however, the underlying mechanism for this protection remains unknown. Herein, the mechanisms contributing to the atheroprotective effect of equol were addressed using apolipoprotein E knockout (apoE-/-) mice fed a high-fat diet (HFD) with or without equol. Equol intervention reduced atherosclerotic lesions in the aorta in HFD-fed apoE-/- mice. Plasma lipid analysis showed that equol intervention reduced triglycerides, total cholesterol and LDL-cholesterol and increased HDL-cholesterol. Additionally, equol administration decreased lipid accumulation in the liver. Simultaneously, equol treatment inhibited cell apoptosis induced by t-BHP and thapsigargin in human umbilical vein endothelial cells (HUVECs). Furthermore, equol treatment attenuated palmitate, t-BHP or thapsigargin-induced upregulation of ER stress markers, including p-PERK, p-eIF2α, GRP78, ATF6 and CHOP proteins expression. The same tendency was also observed in aortic lysates in apoE-/- mice fed with equol plus HFD compared with HFD alone. Moreover, equol treatment dose dependently activated the Nrf2 signaling pathway under oxidative stress. Additionally, elevation of Nrf2 induction was found in aortic lysates in apoE-/- mice fed with a HFD diet containing equol compared with a HFD diet without equol. Importantly, Nrf2 siRNA interference induced CHOP and attenuated the effect of equol to inhibit t-BHP mediated CHOP induction, furthermore, abrogated cell apoptosis induced by t-BHP, suggesting a role for Nrf2 in the protective effect of equol in HUVECs. Collectively, these findings implicate that the improvement of atherosclerosis by equol through attenuation of ER stress is mediated, at least in part, by activating the Nrf2 signaling pathway.

Topics: Activating Transcription Factor 6; Animals; Aorta; Apolipoproteins E; Apoptosis; Atherosclerosis; Cholesterol, HDL; Cholesterol, LDL; Diet, High-Fat; Disease Models, Animal; eIF-2 Kinase; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Equol; Eukaryotic Initiation Factor-2; Gene Expression Regulation; Heat-Shock Proteins; Human Umbilical Vein Endothelial Cells; Humans; Liver; Mice; Mice, Knockout; NF-E2-Related Factor 2; Palmitic Acid; Phytoestrogens; Signal Transduction; Thapsigargin; Transcription Factor CHOP; Triglycerides

To examine effects of equol, the soy phytoestrogen metabolite, on gene expression in the monkey iliac artery.. A high fat/high cholesterol diet was fed to eight ovariectomized cynomolgus monkeys for 6.5 years. After biopsy of the left iliac artery, the animals were randomized to two treatment groups for 8 months; the treatment groups were equol (23.7 mg/100 g diet, n = 4) and vehicle (n = 4). The right iliac artery was removed at necropsy. Gene expression in the iliac arteries in response to equol was determined by DNA microarray. Comparison of atherosclerotic lesions and plasma lipids at pre-versus post-equol treatment time points and in vehicle versus equol treatment groups did not identify any significant differences. Despite the lack of effect of equol on these parameters, 59 genes were down-regulated and 279 were up-regulated in response to equol. Comparison of these data to previous work identified 10 genes regulated in opposite directions by equol compared to presence of atherosclerosis plaque (Menopause 2011; 18:1087-1095) and 55 genes differentially expressed in the same direction in response to both equol and estradiol (Eyster et al., Menopause 2014;21:143-152.).. Similar responses of genes to both equol and estradiol may reflect the extent to which equol serves as a natural selective estrogen receptor modulator in the arteries. Opposite responses of 10 genes to equol versus the presence of atherosclerosis implicates those genes in the potential protective effects of equol in arteries.

Topics: Animals; Atherosclerosis; Diet, High-Fat; Disease Models, Animal; Equol; Female; Gene Expression Regulation; Iliac Artery; Macaca fascicularis; Ovariectomy; Phytoestrogens; Plaque, Atherosclerotic; Time Factors

The aim of the present study was to investigate the cardiac biomarker changes in experimental bilateral ovariectomized (OVX) rats in addition to evaluating the role of soybean oil-supplemented diet to attenuate these alterations. Female rats were divided into four groups and treated for 2 months as follows: groups 1 and 2 fed with standard diet with or without 15% soybean oil. Groups 3 and 4 were bilateral OVX and received the standard diet with or without 15% soybean oil. The results revealed that rats subjected to ovariectomy exhibited an inhibition in estrogen and high-density lipoprotein cholesterol levels and marked increase of lipid profile, low-density lipoprotein cholesterol, and VLDL-C accompanied with a marked elevation in atherogenic index, cardiac enzyme activity, tumor necrosis factor-α, and C-reactive protein. Signs of cardiovascular injury which included an increase in cardiac thiobarbituric acid-reactive substances were concomitantly noticed with a reduction in the reduced glutathione, total antioxidant capacity, and superoxide dismutase. However, supplementation of soybean oil resulted in the restoration of the changed lipid profile and improved cardiac biomarkers near to normal values as well as improved inflammatory and antioxidant status. It was concluded that consumption of soybean oil may have a role in retarding atherosclerosis and risk of cardiovascular disorders associated with estrogen deficiency in ovariectomy status.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Atherosclerosis; C-Reactive Protein; Cardiotonic Agents; Creatine Kinase; Dietary Supplements; Estrogen Replacement Therapy; Estrogens; Female; Glutathione; Hypolipidemic Agents; Lipids; Myocardium; Ovariectomy; Phytoestrogens; Rats; Rats, Sprague-Dawley; Risk Factors; Soybean Oil; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Tumor Necrosis Factor-alpha

Genistein is a phytoestrogen that is known to have a protective effect on the vascular endothelial wall. However, it exhibits poor bioavailability, which limits the use of genistein to treat cardiovascular and cerebrovascular diseases. A novel genistein derivative, 7-difluoromethyl-5,4'-dimethoxygenistein (dFMGEN), has shown a better protective effect on vascular endothelial damage in vitro than genistein. In this study, we further evaluated therapeutic effects of dFMGEN on the vascular endothelial wall and atherosclerosis in a rabbit model in vivo. There were 5 groups: the GEN group (genistein 5 mg/kg per day), lovastatin group (lovastatin 5 mg/kg per day), dFMGEN group (dFMGEN 5 mg/kg per day), model control group (the same amount of vehicle solvent), and the normal control group; all feedings administered via intragastric administration. We demonstrated that dFMGEN (1) attenuated the development of atherosclerosis, (2) reduced serum total cholesterol and low-density lipoprotein cholesterol concentrations, (3) decreased lipid peroxidation in the rabbit atherosclerosis model, and (4) increased smooth muscle cell and collagen content in atheroma of thoracic aortas. These results provide an experimental foundation for dFMGEN's potential effects in preventing and treating atherosclerosis, acute coronary syndromes, and potentially ischemia-reperfusion injury during acute myocardial infarction and cerebral infarction.

Topics: Animals; Aorta, Abdominal; Aorta, Thoracic; Atherosclerosis; Cholesterol; Collagen; Disease Models, Animal; Endothelium, Vascular; Genistein; Lipid Peroxidation; Lipoproteins, LDL; Male; Phytoestrogens; Rabbits

Phystestrogens are organic compounds produced by a large variety of plants with protective function against the invasion of them by microorganisms. Phystestrogens, and among them isoflavones, have a great similarity with estradiol, principal endogenous estrogen. Those known most for their estrogenic activity are daidzeine and genisteine. Due to the existence of contradictory data on the effects of soy isoflavones on the most outstanding health disorders of menopause such as osteoporosis and hot flushes, and its ineffective role in the improvement of the lipid profile, it is recommendable to continue choosing hygienic-dietary and conventional drug treatments. However, we could introduce soy and soy derived products within a balanced, varied and adequate diet for these women.

Topics: Atherosclerosis; Bone Density; Female; Glycine max; Humans; Isoflavones; Lipids; Menopause; Osteoporosis; Phytoestrogens

There is increasing interest in the role of complementary and alternative medicines for the treatment of menopause-related problems. This study compared the preventive effect on atheroma formation of a commercially available mixed phytoestrogen concentrate with that of estradiol.. An ovariectomized cholesterol-fed rabbit model of atheroma formation was used. Rabbits were ovariectomized before the commencement of the 12-week treatment period. There were two control groups. Control Group 1 received isoflavone-free rabbit chow whilst Control Group 2 received 1% cholesterol-enriched isoflavone-free rabbit chow. Rabbits in Group 3 received 1% cholesterol-enriched isoflavone-free rabbit chow plus a 500 mg tablet containing a concentrated extract of Trifolium pretense (red clover). Rabbits in Group 4 received 1% cholesterol-enriched isoflavone-free rabbit chow plus a 0.5 mg tablet of oral estradiol. Atheroma formation was measured by, first, calculation of the area of atheroma on the intimal surface, and, second, measuring the cholesterol content in the aorta.. There were no significant differences in serum cholesterol between the cholesterol-fed control Group 2 and the treatment Groups 3 and 4. However, there was significantly less staining for atheroma and significantly less cholesterol accumulation in the aorta in Group 4 (estradiol-treated) rabbits compared with either control Group 2 or Group 3 (phytoestrogen-treated) rabbits.. In this study, only estradiol was shown to have a significant protective effect against atheroma formation.

Topics: Administration, Oral; Animals; Aorta; Atherosclerosis; Cholesterol; Cholesterol, Dietary; Disease Models, Animal; Estradiol; Female; Ovariectomy; Phytoestrogens; Rabbits; Random Allocation

The effects of grape phytoestrogens on cholesterol accumulation were studied in primary culture of human blood monocytes incubated with blood serum from postmenopausal women obtained before and 2, 4, and 6 h after single intake of plant components of grapes. Phytoestrogens from grape seeds, pressed out grapes, and fermented grape ridges prevent cholesterol accumulation in cells and can be regarded as prospective components for the development of natural preparations for the prevention of atherosclerosis in postmenopausal women.

Topics: Atherosclerosis; Cholesterol; Female; Flavonoids; Humans; Middle Aged; Monocytes; Phytoestrogens; Postmenopause; Time Factors; Vitis