Does genistein lower plasma lipids and homocysteine levels in postmenopausal women? A meta-analysis

Effects of Isoflavonoid and Vitamin D Synergism on Bone Mineral Density-A Systematic and Critical Review

Phytoestrogens are non-steroidal plant compounds, which bind to α and β estrogen receptors, thereby causing specific effects. The best-known group of phytoestrogens are flavonoids, including isoflavonoids-genistein and daidzein. They play a role in the metabolism of bone tissue, improving its density and preventing bone loss, which contributes to reducing the risk of fractures. Vitamin D is found in the form of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) and is traditionally recognized as a regulator of bone metabolism. The aim of this review was to evaluate the synergistic effect of isoflavonoids and vitamin D on bone mineral density (BMD). The MEDLINE (PubMed), Scopus and Cochrane databases were searched independently by two authors. The search strategy included controlled vocabulary and keywords. Reference publications did not provide consistent data regarding the synergistic effect of isoflavonoids on BMD. Some studies demonstrated a positive synergistic effect of these compounds, whereas in others, the authors did not observe any significant differences. Therefore, further research on the synergism of isoflavonoids and vitamin D may contribute to a significant progress in the prevention and treatment of osteoporosis.

Effect of moderate beer consumption (with and without ethanol) on cardiovascular health in postmenopausal women

BACKGROUND

The main aim of this 2-year non-randomized parallel controlled clinical pilot trial was to evaluate the long-term effect of a moderate daily intake of beer (with and without alcohol) on cardiovascular health in postmenopausal women. A total of 34 participants were grouped into three study arms: 16 were administered alcoholic beer, 6 consumed non-alcoholic beer, and 12 were in the control group. Changes in glucose metabolism, lipid profile, liver enzymes, anthropometric measurements, body composition, and blood pressure variables were monitored. Data on medical history, diet, and exercise were collected, and gustatory capacities were determined.

RESULTS

Moderate consumption of beer, both alcoholic and non-alcoholic, seemed to have positive effects on biochemical indicators of cardiovascular health in postmenopausal women, with 660 mL day-1 of non-alcoholic beer reducing low-density lipoprotein cholesterol blood levels, and 330 mL day-1 of alcoholic beer increasing high-density lipoprotein cholesterol. The evolution of changes in android and gynoid fat percentage and their ratio differed significantly between study groups, which was attributable to either the interventions or the disparity between groups regarding the time elapsed since menopause onset. Iso-α-acids recognition threshold could be involved in intervention group election, whereas the sensory phenotypes studied were not associated with alcohol drinking frequency.

CONCLUSIONS

Moderate beer consumption was found to improve the lipid profile of postmenopausal women, although their effects in preventing cardiometabolic alterations deserve further research (trial registration number: ISRCTN13825020; https://doi.org/10.1186/ISRCTN13825020). © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Bioactivity of Dietary Polyphenols: The Role in LDL-C Lowering

Cardiovascular diseases are the leading causes of the death around the world. An elevation of the low-density lipoprotein cholesterol (LDL-C) level is one of the most important risk factors for cardiovascular diseases. To achieve optimal plasma LDL-C levels, clinal therapies were investigated which targeted different metabolism pathways. However, some therapies also caused various adverse effects. Thus, there is a need for new treatment options and/or combination therapies to inhibit the LDL-C level. Dietary polyphenols have received much attention in the prevention of cardiovascular diseases due to their potential LDL-C lowering effects. However, the effectiveness and potential mechanisms of polyphenols in lowering LDL-C is not comprehensively summarized. This review focused on dietary polyphenols that could reduce LDL-C and their mechanisms of action. This review also discussed the limitations and suggestions regarding previous studies.

Intraperitoneal injection of genistein affects the distribution and metabolism of cholesterol in female yellow catfish Tachysurus fulvidraco

Genistein is an abundant phytoestrogen in soybean. This study aimed to determine the effects of genistein on cholesterol distribution and metabolism in female yellow catfish. Three hundred fish (49.2 ± 1.4 g) were randomly divided into five treatments and received intraperitoneal injections as follows: (1) blank, no injection; (2) control, vehicle only; (3) E2, 17β-estradiol at 10 μg·g^-1 body weight; (4) low genistein doses, genistein at 10 μg·g^-1 body weight; (5) high genistein doses, genistein at 100 μg·g^-1 body weight. Both high and low genistein doses significantly reduced (p < 0.05) serum TC and LDL-C 24 h after injection. Moreover, the high genistein doses significantly reduced (p < 0.05) serum HDL-C. Both high and low doses of genistein significantly increased (p < 0.05) hepatic TC. Only high genistein doses significantly increased (p < 0.05) ovary TC. In the liver, both high and low genistein doses significantly increased (p < 0.05) protein and mRNA expression of ldlr. Meanwhile, high genistein doses significantly decreased (p < 0.05) mRNA expression of hmgcr. In ovary tissue, high genistein doses significantly decreased (p < 0.05) mRNA expression of cyp11a1. These results suggested that genistein affected the cholesterol distribution in female yellow catfish. Both high and low doses of genistein reduced cholesterol content in blood and increased its content in the liver by increasing the uptake of blood cholesterol. Meanwhile, high genistein doses may inhibit hepatic cholesterol synthesis. Additionally, high genistein doses could increase cholesterol transfer from serum into the ovary and disturb cholesterol conversion to pregnenolone.

Effect of Genistein Intake on Some Cardiovascular Risk Factors: An Updated Systematic Review and Meta-analysis

Genistein, an isoflavone in soybean products has potential cardio-protective effects and is used also as an alternative for estrogen therapy in postmenopausal women. However, results in this regard are inconsistent and also, not all risk factors related to cardiovascular supportive effects have been meta-analyzed. We searched PubMed, Scopus, ISI Web of Science, and Google Scholar from inception up to October 2020. Random-effects meta-analysis was used for data synthesis. The search included studies with information on genistein supplementation and lipid profile [triglycerides (TG), total cholesterol (TC),low-density lipoprotein (LDL-C), and high-density lipoprotein HDL-C)], systolic and diastolic blood pressure (SBP & DBP), body mass index [BMI] and body weight. Pooled results of studies showed that genistein intake significantly reduced TC [95%CI: -0.49(-0.80, -0.18); P=0.002)], LDL-C [95%CI: -0.60(-1.10, -0.10); P=0.018)] and SBP [95%CI: -0.52(-0.90, -0.14); P=0.007)]. DBP, HLD-C, TG, BMI, and body weight showed no meaningful improvement. Subgroup analysis showed that LDL-C and SBP were reduced more effectively in postmenopausal women with metabolic syndrome. Genistein intake more than 6 months showed a greater effect on lowering cholesterol -0.76(-1.27, -0.24), SBP [-0.39(-0.70, -0.08)] and DBP -0.40(-0.81, -0.00) and increasing TG and LDL-C. This meta-analysis provides consistent evidence that genistein intake reduces the CVD risk factors of TC, LDL-C, and SBP significantly.

Genistein for glycolipid metabolism in postmenopausal women: a meta-analysis

OBJECTIVE

This study aimed to evaluate the effects of genistein on glycolipid metabolism in postmenopausal women.

METHODS

Electronic databases were searched and relevant reports were hand-screened. We included only randomized controlled trials of isolated genistein for glycolipid metabolism. The primary outcome for lipid metabolism included a changed value of low-density lipoprotein cholesterol (LDL-C), and for glucose metabolism was a changed value of homeostasis model assessment for insulin resistance (HOMA-IR). Secondary outcomes included a changed value of total cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), fasting blood insulin (INS), and body mass index (BMI).

RESULTS

Ten trials with 11 articles were included. The level of LDL-C was not decreased in the genistein group compared with the placebo group (standardized mean difference [SMD] = -0.58; 95% confidence interval [CI] - 1.19, 0.02; p = 0.06). No statistical significance was found in subgroup analyses. HOMA-IR was obviously improved in the genistein group with SMD of -0.51 (95% CI -0.88, -0.14; p = 0.006). In subgroup analyses, HOMA-IR was improved more in women with BMI <30 kg/m² and without metabolic disorders (p < 0.0001). For secondary outcomes, there were significant differences in total cholesterol, HDL-C, FBG, and INS, but not triglyceride or BMI.

CONCLUSIONS

Genistein was effective in ameliorating glycolipid metabolism by increasing HDL-C levels and decreasing total cholesterol levels and improving insulin sensitivity.

Effect of Genistein on Cholesterol Metabolism-Related Genes in HepG2 Cell

It has been reported that genistein could improve metabolic syndromes. Our study aimed to investigate the effects and potential mechanisms of genistein on improving cholesterol metabolism in HepG2 cell. HepG2 cells were cultured with 0, 0.01, 1.00, 10.00, and 50.00 µM genistein for 24 hr. The current results showed a dose-dependent manner between genistein and intracellular contents of total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), and cellular apolipoprotein A1 (Apo-A1) secretion. TC was increased by 25.69%, meanwhile HDL-C and Apo-A1 were decreased by 56.00% and 25.93%, respectively, when the dosage of genistein was 1.00 µM. Genistein dose-dependently upregulated the protein and mRNA levels of sterol regulatory element binding proteins-2 (SREBP-2), as well as the mRNA levels of low-density lipoprotein receptor (LDLR) and 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMGCR), by 145.91%, 72.29%, 310.23%, and 123.08%, respectively, when we gave 1.00 µM genistein, indicating that intracellular cholesterol synthesis and absorption of exogenous cholesterol were increased. In addition, the mRNA levels of peroxisome proliferator-activated receptor-γ (PPARγ) and liver X receptor (LXRα), lowered by 58.23% and 34.86% at 0.01 µM genistein, were reduced in a dose-dependent manner. LXRα and ATP-binding cassette transporter A1 (ABCA1) protein levels were significantly (P < 0.05) decreased by 50.35% and 11.60% at 1.00 µM genistein, which indicated that cellular cholesterol efflux was inhibited. Taken together, our results suggested that genistein at dosage of more than 1.00 µM was able to increase the intracellular cholesterol levels by up regulating SREBP-2/LDLR/HMGCR pathway and suppressing PPARγ/LXRα/ABCA1 pathway. PRACTICAL APPLICATION: In this study, genistein appeared to be effective in reducing plasma cholesterol levels due to increase the intracellular cholesterol levels by upregulating cholesterol absorption through SREBP-2/LDLR/HMGCR pathway, and also downregulating cholesterol efflux via PPARγ/LXRα/ABCA1 pathway in vitro. In addition, plasma cholesterol is regarded as the key indicator of atherosclerosis; therefore, we believe that our findings could be used for further exploration on a possible therapeutic application of genistein for atherosclerosis.

Age of Postmenopause Women: Effect of Soy Isoflavone in Lipoprotein and Inflammation Markers

Objectives

Menopause is associated with adverse metabolic changes in plasma lipoprotein and inflammation markers. Estrogens have beneficial effects on lipid metabolism and inflammation. Isoflavones (ISO) have structurally similar to estradiol. Our objective was analize the effect of soy-ISO on serum lipid and inflammatory markers (sP-selectin and sCD40L) in postmenopausal women.

Methods

A 12-week randomized, double-blind, placebo-controlled intervention with soy-ISO (50 mg, twice daily) was conducted in 35 healthy postmenopausal women (55-72 years old). The women were divided in 2 groups: 20 were allocated to soy-ISO, and 15 to a placebo group.

Results

The changes of total cholesterol (TC), triglycerides, low-density lipoproteins-cholesterol (LDL-C), high-density lipoprotein-cholesterol, Apo-A1, sP-selectin and sCD40L in 2 groups before and after 12-week treatment showed no statistical significance. In subgroup analysis, soy-ISO supplementation significantly decreased the levels of TC, LDL-C and sCD40L in women under 65 years old, and with null effects on serum lipid and inflammation markers in women over 65 years old.

Conclusions

Soy-ISO did not significantly favorable effects on the lipid profile and inflammatory markers in postmenopausal women. However, in women under 65 years of age, soy-ISO significantly decreased the TC, LDL-C and sCD40L, whereas, no effects on lipid profile and inflammation markers in women over 65 years old were observed.

Consuming Genistein Improves Survival Rates in the Absence of Laxative in ΔF508-CF Female Mice

Genistein is a naturally occurring isoflavone found in soy. Genistein has been shown to increase the open probability of the most common cystic fibrosis (CF) disease-associated mutation, ∆F508-CFTR. Mice homozygous for the ∆F508 mutation are characterized with severe intestinal disease and require constant laxative treatment for survival. This pathology mimics the intestinal obstruction (meconium ileus) seen in some cystic fibrosis patients. This study tested whether dietary supplementation with genistein would reduce the dependence of the ∆F508 CF mouse model on laxatives for survival, thereby improving mortality rates. At weaning (21 days), homozygous ∆F508 mice were maintained on one of three diet regimens for a period of up to 65 days: normal diet, normal diet plus colyte, or genistein diet. Survival rates for males were as follows: standard diet (38%, n = 21), standard diet plus colyte (83%, n = 42) and genistein diet (60%, n = 15). Survival rates for females were as follows: standard diet (47%, n = 19), standard diet plus colyte (71%, n = 38), and genistein diet (87%, n = 15). Average weight of male mice fed genistein diet increased by ~2.5 g more (p = 0.006) compared to those with colyte treatment. Genistein diet did not change final body weight of females. Expression of intestinal SGLT-1 increased 2-fold (p = 0.0005) with genistein diet in females (no change in males, p = 0.722). Expression of GLUT2 and GLUT5 was comparable between all diet groups. Genistein diet reduced the number of goblet cells per micrometer of crypt depth in female (p = 0.0483), yet was without effect in males (p = 0.7267). The results from this study demonstrate that supplementation of diet with genistein for ~45 days increases the survival rate of female ∆F508-CF mice (precluding the requirement for laxatives), and genistein only improves weight gain in males.