Effect of soy isoflavone supplementation on blood pressure: a meta-analysis of randomized controlled trials.

BACKGROUND: Previous experimental studies have suggested that the consumption of soy isoflavones may have a potential impact on lowering blood pressure. Nevertheless, epidemiological studies have presented conflicting outcomes concerning the correlation between soy isoflavone consumption and blood pressure levels. Consequently, a comprehensive meta-analysis of all eligible randomized controlled trials (RCTs) was conducted to explore the influence of soy isoflavones on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults. METHODS: A thorough search of PubMed, Embase, and the Cochrane Library for relevant literature up to April 30, 2023 was conducted. RCTs involving adults that compared soy isoflavone supplementation with a placebo (the same matrix devoid of soy isoflavone) were included. The combined effect size was presented as the weighted mean difference (WMD) along with 95% confidence interval (CI), employing a fixed-effects model. RESULTS: Our meta-analysis included a total of 24 studies involving 1945 participants. The results revealed a significant reduction in both SBP and DBP with soy isoflavone supplementation. Subgroup analyses suggested more pronounced reductions in SBP and DBP for interventions lasting ≥6 months, in individuals receiving mixed-type soy isoflavone, and among patients with metabolic syndrome or prehypertension. However, we did not detect significant nonlinear associations between supplementation dosage and intervention duration concerning both SBP and DBP. The overall quality of evidence was deemed moderate. CONCLUSIONS: The current meta-analysis revealed that supplementation with soy isoflavones alone effectively reduces blood pressure. Additional high-quality studies are required to investigate the efficacy of blood pressure reduction through supplementation with an optimal quantity and proportion of soy isoflavone.

Novel pH-responsive E-selectin targeting natural polysaccharides hybrid micelles for diabetic nephropathy.

Diabetic nephropathy (DN) is an important complication of diabetes and is the main cause of end-stage renal disease. The pathogenesis of DN is complex, including glucose and lipid metabolism disorder, inflammation, and so on. Novel hybrid micelles loaded Puerarin (Pue) based on Angelica sinensis polysaccharides (ASP) and Astragalus polysaccharide (APS) were fabricated with pH-responsive ASP-hydrazone-ibuprofen (BF) materials (ASP-HZ-BF, SHB) and sialic acid (SA) modified APS-hydrazone-ibuprofen materials (SA/APS-HZ-BF, SPHB) by thin-film dispersion method. The SA in hybrid micelles can specifically bind to the E-selectin receptor which is highly expressed in inflammatory vascular endothelial cells. The loaded Pue could be accurately delivered to the inflammatory site of the kidney in response to the low pH microenvironment. Overall, this study provides a promising strategy for developing hybrid micelles based on natural polysaccharides for the treatment of diabetic nephropathy by inhibiting renal inflammatory reactions, and antioxidant stress.

Daidzein suppresses TGF-ß1-induced cardiac fibroblast activation via the TGF-ß1/SMAD2/3 signaling pathway.

Myocardial fibrosis is a concomitant bioprocess associated with many cardiovascular diseases (CVDs). Daidzein is an isoflavone that has been used for the treatment of CVDs. This study aimed to reveal its role in myocardial fibrosis. Our results indicate that daidzein had a nontoxic effect on cardiac fibroblasts and that TGF-ß1 and TGFßRI levels were gradually decreased by daidzein in a dose-dependent manner. In the current study, we show that daidzein significantly inhibited TGF-ß1-induced mRNA and protein expression of α-SMA, collagen I, and collagen III. Accordingly, immunofluorescence staining of α-SMA was performed. Daidzein also inhibited TGF-ß1-induced cardiac fibroblast proliferation and migration. Mechanistically, daidzein inhibited the TGF-ß/SMAD signaling pathway induced by TGF-ß1 in cardiac fibroblasts. Additionally, daidzein ameliorated MI-induced cardiac dysfunction and cardiac fibrosis in vivo. Based on these findings, we conclude that daidzein reduces TGF-ß1-induced cardiac fibroblast activation by partially regulating the TGF-ß1/SMAD2/3 signaling pathway.

Food composition can influence how much alcohol your animal model drinks: A mini-review about the role of isoflavones.

Standard laboratory diets used have similar concentrations of proteins, carbohydrates and fat, but the concentration of some micronutrients can vary considerably. For example, the concentration of isoflavones can vary between 20 mg and 600 mg per gram of diet. Exposure to different concentrations of isoflavones interacts with alcohol (EtOH) intake, thereby influencing the results of alcohol research. In this mini-review, we describe correlations between isoflavone concentrations and alcohol intake based on data from previously published work. Although the administration of low doses of isoflavones can decrease alcohol intake in rats, there is a positive correlation between the isoflavone content in diets and alcohol intake in mice. This interaction seems to depend on the dose, route of administration, and time of exposure to isoflavones and may be related to specific neurobiological mechanisms. The literature also indicates that isoflavones can interact with some of alcohol's molecular targets and with neural pathways crucial to the alcohol reward process. Given these findings, more attention should be given to the different types of laboratory diets used in alcohol studies to allow better comparison and replication of animal research.

Effects of Soy Isoflavones, Resistant Starch and Antibiotics on Polycystic Ovary Syndrome (PCOS)-Like Features in Letrozole-Treated Rats.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-aged women. Recently, various dietary interventions have been used extensively as a novel therapy against PCOS. In the present study, we show that soy isoflavone metabolites and resistant starch, together with gut microbiota modulations, were successful in decreasing the severity of PCOS-like reproductive features while increasing the expression of gut barrier markers and butyric acid in the gut. In the letrozole-induced PCOS model rats, the intake of both 0.05% soy isoflavones and 11% resistant starch, even with letrozole treatment, reduced the severity of menstrual irregularity and polycystic ovaries with a high concentration of soy isoflavones and equol in plasma. Antibiotic cocktail treatment suppressed soy isoflavone metabolism in the gut and showed no considerable effects on reducing the PCOS-like symptoms. The mRNA expression level of occludin significantly increased with soy isoflavone and resistant starch combined treatment. Bacterial genera such as Blautia, Dorea and Clostridium were positively correlated with menstrual irregularity under resistant starch intake. Moreover, the concentration of butyric acid was elevated by resistant starch intake. In conclusion, we propose that both dietary interventions and gut microbiota modulations could be effectively used in reducing the severity of PCOS reproductive features.

Acute myocardial infarction therapy: in vitro and in vivo evaluation of atrial natriuretic peptide and triphenylphosphonium dual ligands modified, baicalin-loaded nanoparticulate system.

BACKGROUND: Myocardial infarction (MI) is one of the most common ischemic heart diseases. It is very essential to explore new types of cardioprotective drugs delivery systems in this area. OBJECTIVE: The aim of the present study was to investigate the protective effect of baicalin (BA) and puerarin (PU) against acute MI rat models. BA and PU co-loaded nanoparticulate system were developed to improve bioavailability of the drugs, to prolong retention time in vivo and to enhance the protective effect. METHODS: In the present study, ANP and TPP contained ligands were synthesized. ANP/TPP-BN-LPNs were prepared and its physico-chemical properties were evaluated. The MI therapy efficiency of ANP/TPP-BN-LPNs was assessed in rats after intravenous injection. Single ligand contained LPNs, no ligand contained LPNs, and BN solution formulations were also prepared and used for the comparison. RESULTS: ANP/TPP-BN-LPNs were uniform and spheroidal particles. The size of ANP/TPP-BN-LPNs was 98.5 ± 2.9 nm, with a zeta potential of -19.5 ± 1.9 mV. The dual ligands modified LPNs exhibited significantly improved therapeutic efficiency compared with the single ligand modified LPNs and other systems. In vivo infarct therapy studies in rats proved that ANP/TPP-BN-LPNs were a promising system for efficient delivery of cardiovascular drugs for the treatment of cardiovascular diseases. CONCLUSIONS: ANP/TPP-BN-LPNs could be used as a long-circulating and heart-targeting drug delivery system.

Methylophiopogonanone A is a naturally occurring broad-spectrum inhibitor against human UDP-glucuronosyltransferases: Inhibition behaviours and implication in herb-drug interactions.

Methylophiopogonanone A (MOA) is an abundant homoisoflavonoid in the Chinese herb Ophiopogonis Radix. Recent investigations revealed that MOA inhibited several human cytochrome P450 enzymes (CYPs) and stimulated OATP1B1. However, the inhibitory effects of MOA on phase II drug-metabolizing enzymes, such as human UDP-glucuronosyltransferases (hUGTs), have not been well investigated. Herein, the inhibition potentials of MOA on hUGTs were assessed. The results clearly demonstrated that MOA dose-dependently inhibited all tested hUGTs including UGT1A1 (IC50 = 1.23 µM), one of the most important detoxification enzymes in humans. Further investigations showed that MOA strongly inhibited UGT1A1-catalysed NHPH-O-glucuronidation in a range of biological settings including hUGT1A1, human liver microsomes (HLM) and HeLa cells overexpressing UGT1A1. Inhibition kinetic analyses demonstrated that MOA competitively inhibited UGT1A1-catalysed NHPH-O-glucuronidation in both hUGT1A1 and HLM, with Ki values of 0.52 and 1.22 µM, respectively. Collectively, our findings expanded knowledge of the interactions between MOA and human drug-metabolizing enzymes, which would be very helpful for guiding the use of MOA-related herbal products in clinical settings.

Soy Isoflavones Intake and Obesity in Chinese Adults: A Cross-Sectional Study in Shanghai, China.

This study was designed to examine the association of soy isoflavones (SI) intake with different body measurements indicative of obesity in Chinese adults of Shanghai, a population consuming foods rich in SI. This study used baseline data from the Shanghai Gaofeng cohort study. SI intake was measured by using a self-reported food frequency questionnaire (FFQ). A restricted cubic spline (RCS) was performed to examine the possible nonlinear relationship of SI intake with obesity. A logistic regression model was applied to estimate the odds ratios (OR) and 95% confidence interval (CI). Compared with the lowest tertile group of SI intake, the highest tertile group had a lower prevalence of obesity and central obesity. The OR for overall obesity was 0.91 (95% CI: 0.85, 0.98) in the highest versus the lowest SI tertile group; the associations differed by sex and menopausal status. A negative association was also observed between SI intake and central obesity, and a significant modifying effect of sex was found on the association. No significant interactions were observed between SI intake and physical activity (PA) levels. Our results suggest that Chinese adults with higher dietary intake of SI may be less likely to be obese, particularly for postmenopausal women.

Effects of Soy Protein Containing of Isoflavones and Isoflavones Extract on Plasma Lipid Profile in Postmenopausal Women as a Potential Prevention Factor in Cardiovascular Diseases: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The aim of the report was to evaluate the impact of soy protein containing isoflavones and soy isoflavones extract on lipid profile in postmenopausal women, as compared with placebo or protein of milk, casein or isolated soy protein with or without trace isoflavone content. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Quantitative data synthesis was performed by applying a random-effects model. Subgroup analysis and meta-regression were performed to assess the modifiers of treatment response. In total, in the analysis studies, 2305 postmenopausal women took part. Changes in the lipid profile showed statistically significant decreases of total cholesterol by -0.12 (95% CI: -0.21, -0.03) mmol/L, -4.64 (95% CI: -8.12, -1.16) mg/dL, p = 0.01 and increased HDL-cholesterol by 0.03 (95% CI: 0.00, 0.06) mmol/L, 1.15 (95% CI: 0.00, 1.93) mg/dL, p = 0.05, as well as in LDL-cholesterol -0.05 (95% CI: -0.11, 0.01) mmol/L, -1.93 (95% CI: -4.25, 0.39) mg/dL, p = 0.08 and triacylglycerols -0.07 (95% CI: -0.14, 0.00) mmol/L, -6.123 (95% CI: -12.25, 0.00) mg/dL, p = 0.06. Our results suggests that soy and its isoflavones can be effective in correction changes in lipid metabolism in postmenopausal women and may favorably influence in preventing cardiovascular events.

Effect of the Intake of Isoflavones on Risk Factors of Breast Cancer-A Systematic Review of Randomized Controlled Intervention Studies.

Epidemiological studies suggest that high intake of soy isoflavones may protect against breast cancer, but causal relationships can only be established by experimental trials. Thus, we aimed to provide a systematic review of randomized controlled trials (RCTs) on the effect of an isoflavone intake on risk factors of breast cancer in healthy subjects. After a systematic literature search in PubMed, 18 different RCTs with pre- and/or postmenopausal women were included and investigated for details according to the PRISMA guideline. In these studies, isoflavones were provided by soy food or supplements in amounts between 36.5-235 mg/d for a period of 1-36 months. Breast density, estrogens including precursors, metabolites, estrogen response such as length of menstrual cycle, and markers of proliferation and inflammation were considered. However, in most studies, differences were not detectable between isoflavone and control/placebo treatment despite a good adherence to isoflavone treatment, irrespective of the kind of intervention, the dose of isoflavones used, and the duration of isoflavone treatment. However, the lack of significant changes in most studies does not prove the lack of effects as a sample size calculation was often missing. Taking into account the risk of bias and methodological limitations, there is little evidence that isoflavone treatment modulates risk factors of breast cancer in pre- and postmenopausal women. Future studies should calculate the sample size to detect possible effects and consider methodological details to improve the study quality.

Effects of daidzein and genistein on markers of cardiovascular disease risk among women with impaired glucose regulation: a double-blind, randomized, placebo-controlled trial.

BACKGROUND AND OBJECTIVE: soy protein and soy isoflavones have been suggested to be associated with improved cardiovascular risk factors (e.g., lipid profiles and uric acid (UA)), but few studies have been conducted among women with impaired glucose regulation (IGR). This study is aimed to evaluate the effect of isolated daidzein and genistein on lipid profiles, high sensitive C-reactive protein (hs-CRP), and uric acid (UA) among Chinese women with IGR. METHODS AND RESULTS: this randomized, double-blind, and placebo-controlled trial was conducted in 165 Chinese women aged 30-70 years with IGR. Participants were randomly assigned to one of the three groups: 0 mg of daidzein and genistein with 10 g soy protein (placebo group), 50 mg of daidzein with 10 g soy protein (daidzein group), or 50 mg of genistein with 10 g soy protein (genistein group) supplementation for 24 weeks. Fasting serum total cholesterol (TC), triacylglycerol (TG), high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), lipoprotein a (LP (a)), hs-CRP, and UA were assessed at baseline, 12, and 24 weeks after intervention. The results showed no significant differences in the changes (%) of TC, TG, HDL-C, LDL-C, LP (a), hs-CRP, and UA between the three treatment groups at weeks 12 or 24 (all P > 0.05). CONCLUSION: neither isolated daidzein nor genistein had a significant effect on cardiovascular health in Chinese women with IGR.

Potential Glioprotective Strategies Against Diabetes-Induced Brain Toxicity.

Astrocytes are crucial for the maintenance of brain homeostasis by actively participating in the metabolism of glucose, which is the main energy substrate for the central nervous system (CNS), in addition to other supportive functions. More specifically, astrocytes support neurons through the metabolic coupling of synaptic activity and glucose utilization. As such, diabetes mellitus (DM) and consequent glucose metabolism disorders induce astrocyte damage, affecting CNS functionality. Glioprotective molecules can promote protection by improving glial functions and avoiding toxicity in different pathological conditions, including DM. Therefore, this review discusses specific pathomechanisms associated with DM/glucose metabolism disorder-induced gliotoxicity, namely astrocyte metabolism, redox homeostasis/mitochondrial activity, inflammation, and glial signaling pathways. Studies investigating natural products as potential glioprotective strategies against these deleterious effects of DM/glucose metabolism disorders are also reviewed herein. These products include carotenoids, catechins, isoflavones, lipoic acid, polysaccharides, resveratrol, and sulforaphane.

Effects of soy isoflavone supplementation on patients with diabetic nephropathy: a systematic review and meta-analysis of randomized controlled trials.

Diabetic nephropathy (DN) is a microvascular complication that is becoming a worldwide public health concern. The aim of this study was to assess the effects of dietary soy isoflavone intervention on renal function and metabolic syndrome markers in DN patients. Seven databases including Medline, the Cochrane Central Register of Controlled Trials, Science Direct, Web of Science, Embase, China National Knowledge Infrastructure, and WanFang were searched for controlled trials that assessed the effects of soy isoflavone treatment in DN patients. Finally, a total of 141 patients from 7 randomized controlled trials were included. The meta-analysis showed that dietary soy isoflavones significantly decreased 24-hour urine protein, C-reactive protein (CRP), blood urea nitrogen (BUN), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and fasting blood glucose (FBG) in DN patients. The standard mean difference was -2.58 (95% CI: -3.94, -1.22; P = 0.0002) for 24-hour urine protein, -0.67 (95% CI: -0.94, -0.41; P < 0.00001) for BUN, -6.16 (95% CI: -9.02, -3.31; P < 0.0001) for CRP, -0.58 (95% CI: -0.83, -0.33; P < 0.00001) for TC, -0.41 (95% CI: -0.66, -0.16; P < 0.00001) for TG, -0.68 (95% CI: -0.94, -0.42; P < 0.00001) for LDL-C, and -0.39 (95% CI: -0.68, -0.10; P = 0.008) for FBG. Therefore, soy isoflavones may ameliorate DN by significantly decreasing 24-hour urine protein, BUN, CRP, TC, TG, LDL-C, and FBG.

Engineering of hybrid anticancer drug-loaded polymeric nanoparticles delivery system for the treatment and care of lung cancer therapy.

Chemotherapy with combination drugs has become one of the most commonly used cancer prevention treatments, with positive clinical results. The goal of this study was to develop compostable polymeric nanomaterials (NMs) for the delivery of puerarin (PRN) and 5-fluorouracil (5FU), as well as to investigate the anticancer activity of the drug delivery system (PRN-5FU NMs) against in vitro and in vivo lung cancer cells. Since double antitumor drugs PRN and 5FU are insufficiently compressed in polymer-based bio-degradable nanoparticles, encapsulation of PRN and 5FU antitumor drugs were co-encapsulated with polyethylene glycol and polylactidecoglycolide nanoparticles (NMs) is efficient. The arrangement of PRN NMs, 5FU NMs, and PRN-5FU NMs, as well as the nanoparticles shape and scale, were studied using transmission electron microscopy (TEM). 5FU-PRN NMs triggered apoptosis in lung carcinoma cell lines such as HEL-299 and A549 in vitro. Acridine orange/ethidium bromide (AO/EB) and nuclear damaging staining techniques were used to observe morphologies and cell death. The mechanistic analysis of apoptosis was also confirmed by flow cytometry analysis using dual staining. When compared to free anticancer products, the hemolysis analysis findings of the 5FU-PRN NMs showed excellent biocompatibility. Taken together the advantages, this combination drug conveyance strategy exposed that 5FU-PRN NMs could have a significant promising to improve the effectiveness of lung cancer cells.

Association of dietary isoflavone consumption with subclinical cardiovascular disease in middle-aged and elderly Chinese people.

BACKGROUND AND AIMS: The association between isoflavone (ISF) consumption and cardiovascular disease (CVD) remains controversial because of limited evidence. Carotid atherosclerosis is an established indicator of subclinical CVD. The study aimed to investigate the relationship between dietary ISF intake and subclinical CVD in middle-aged and elderly adults. METHODS AND RESULTS: A total of 873 subjects aged 40-70 years without CVD were enrolled in this cross-sectional study. A restricted cubic spline was used to investigate the association between ISF intake and subclinical CVD risk. The odds ratio (OR) and 95% confidence interval of the risk of subclinical CVD for ISF were estimated by two-segmented logistic regression analysis. In Model 2, there was a non-linear association between ISF intake and the risk of subclinical CVD among women (Pnon-linear = 0.002), with an inverse association below the change point. The nadir for the risk of subclinical CVD among women was 7.26 mg/day (energy-adjusted). Below the change point, an increase of 1 mg ISF/day reduced the risk of subclinical CVD by 15%. There was no significant association between ISF intake and subclinical CVD risk above the change point (OR = 1.01 [0.99, 1.04]). ISF intake was not associated with subclinical CVD risk in men (Model 2: Pnon-linear = 0.224). CONCLUSIONS: Below the change point (7.26 mg/day), women with a higher intake of ISF had a significantly lower risk of subclinical CVD. Encouraging the consumption of ISF-rich foods may help to lower CVD risk in middle-aged and elderly women. TRIAL REGISTRATION: This study is registered at http://www.chictr.org.cn (ChiCTR 1900022445).

Therapeutic effects of puerarin on polycystic ovary syndrome: A randomized trial in Chinese women.

BACKGROUND: This study aims to assess the therapeutic effects of a well-known component (puerarin) obtained from a Chinese herb root in patients with polycystic ovary syndrome (PCOS). METHODS: Women with premature ovarian failure (POF) were assigned to the obese group (body mass index [BMI] ≥24 kg/m2 and waist hip ratio [WHR] >0.85) or non-obese group (group 3, n = 21). Obese patients were further randomly assigned to the obese treatment group (group 1, n = 15) and obese control group (group 1, n = 15). All patients received standard treatment (Diane-35, 1 tablet/d, orally, plus metformin, 1.5 g/d, orally). In addition to the standard modality, patients in group 1 and group 3 also orally received 150 mg/d of puerarin tablets for 3 months. Venous blood was drawn before and after treatment. Then, the metabolic and antioxidant biomarkers were measured. The normality of distribution of the data was tested using the Kolmogorov-Smirnov method. The baseline characteristics were analyzed using one-factor analysis of variance (ANOVA), and post-hoc was performed using the least significance difference (LSD)-t test. RESULTS: Significantly improved blood levels of sex hormone binding globulin (SHBG) and superoxide dismutase (SOD) were observed in patients who received the additional treatment of puerarin, regardless of their lean or obese status, while these were not observed in patients who did not receive puerarin. Furthermore, obese patients with PCOS had significantly lower systolic blood pressure, total cholesterol, and testosterone blood levels, when compared with before treatment. CONCLUSION: The addition of puerarin to the present treatment protocol can be considered for the management of metabolic disorders and hyperandrogenism in PCOS patients.

Maternal consumption of soy and isoflavones during pregnancy and risk of childhood behavioural problems: the Kyushu Okinawa Maternal and Child Health Study.

It is uncertain whether the effects of prenatal exposure to isoflavones on childhood behaviour are beneficial or detrimental. This prebirth cohort study investigated the associations between maternal consumption of soy products and isoflavones during pregnancy and behavioural problems in Japanese children aged 5 years. Subjects were 1199 mother-child pairs. Emotional problems, conduct problems, hyperactivity problems, peer problems and low prosocial behaviour were assessed using the Strengths and Difficulties Questionnaire. Maternal total soy product consumption during pregnancy was independently inversely associated with childhood hyperactivity and peer problems. Maternal fermented soybean consumption during pregnancy was independently inversely associated with childhood hyperactivity problems. Maternal isoflavone consumption during pregnancy was independently inversely related to childhood hyperactivity problems. Maternal consumption of total soy products, fermented soybean and isoflavones during pregnancy may be protective against hyperactivity problems in Japanese children. Also, maternal total soy product consumption during pregnancy may be preventive against childhood peer problems.

Association between Soy Food and Dietary Soy Isoflavone Intake and the Risk of Cardiovascular Disease in Women: A Prospective Cohort Study in Korea.

The association between soy food and soy isoflavone intake and cardiovascular disease (CVD) risk is uncertain, especially in women. We aimed to investigate this association in Korean women. We analyzed data from the Korean Genome and Epidemiology Study, including 4713 Korean women aged 40-69 years with no CVD or cancer at baseline. Dietary information was obtained using a validated semi-quantitative food frequency questionnaire, and the incidence of CVD was assessed using biennial self-reported questionnaires on medical history. The mean follow-up time was 7.4 years, during which 82 premenopausal and 200 postmenopausal women reported CVD incidence. The highest tofu, total soy foods, and dietary soy isoflavone intake groups were significantly associated with a decreased CVD risk in premenopausal women (tofu: hazard ratio (HR) 0.39; 95% confidence interval (CI), 0.19-0.80; total soy food: HR 0.36; 95% CI, 0.18-0.70; dietary soy isoflavones: HR 0.44; 95% CI, 0.22-0.89), whereas no association was observed in postmenopausal women. Other soy foods showed no association with CVD incidence. Dietary soy isoflavones and total soy foods are associated with a decreased CVD risk in premenopausal women. Among soy foods, only tofu showed significant health benefits.

Evaluation of Clinical Meaningfulness of Red Clover (Trifolium pratense L.) Extract to Relieve Hot Flushes and Menopausal Symptoms in Peri- and Post-Menopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The meta-analysis presented in this article covered the efficacy of red clover isoflavones in relieving hot flushes and menopausal symptoms in perimenopausal and postmenopausal women. Studies were identified by MEDLINE (PubMed), Embase, and the Cochrane Library searches. The quality of the studies was evaluated according to Cochrane criteria. A meta-analysis of eight trials (ten comparisons) demonstrated a statistically significant reduction in the daily incidence of hot flushes in women receiving red clover compared to those receiving placebo: weighted mean difference (WMD-weighted mean difference) -1.73 hot flushes per day, 95% CI (confidence interval) -3.28 to -0.18; p = 0.0292. Due to 87.34% homogeneity, the performed analysis showed substantive difference in comparisons of postmenopausal women with ≥5 hot flushes per day, when the follow-up period was 12 weeks, with an isoflavone dose of ≥80 mg/day, and when the formulations contained a higher proportion of biochanin A. The meta-analysis of included studies assessing the effect of red clover isoflavone extract on menopausal symptoms showed a statistically moderate relationship with the reduction in the daily frequency of hot flushes. However, further well-designed studies are required to confirm the present findings and to finally determine the effects of red clover on the relief of flushing episodes.

Utilization of Isoflavones in Soybeans for Women with Menopausal Syndrome: An Overview.

Based on their nutrient composition, soybeans and related foods have been considered to be nutritious and healthy for humans. Particularly, the biological activity and subsequent benefits of soy products may be associated with the presence of isoflavone in soybeans. As an alternative treatment for menopause-related symptoms, isoflavone has gained much popularity for postmenopausal women who have concerns related to undergoing hormone replacement therapy. However, current research has still not reached a consensus on the effects of isoflavone on humans. This overview is a summary of the current literature about the processing of soybeans and isoflavone types (daidzein, genistein, and S-equol) and supplements and their extraction and analysis as well as information about the utilization of isoflavones in soybeans. The processes of preparation (cleaning, drying, crushing and dehulling) and extraction of soybeans are implemented to produce refined soy oil, soy lecithin, free fatty acids, glycerol and soybean meal. The remaining components consist of inorganic constituents (minerals) and the minor components of biologically interesting small molecules. Regarding the preventive effects on diseases or cancers, a higher intake of isoflavones is associated with a moderately lower risk of developing coronary heart disease. It may also reduce the risks of breast and colorectal cancer as well as the incidence of breast cancer recurrence. Consumption of isoflavones or soy foods is associated with reduced risks of endometrial and bladder cancer. Regarding the therapeutic effects on menopausal syndrome or other diseases, isoflavones have been found to alleviate vasomotor syndromes even after considering placebo effects, reduce bone loss in the spine and ameliorate hypertension and in vitro glycemic control. They may also alleviate depressive symptoms during pregnancy. On the other hand, isoflavones have not shown definitive effects regarding improving cognition and urogenital symptoms. Because of lacking standardization in the study designs, such as the ingredients and doses of isoflavones and the durations and outcomes of trials, it currently remains difficult to draw overall conclusions for all aspects of isoflavones. These limitations warrant further investigations of isoflavone use for women's health.