Phytoestrogens and the menopause

Efficacy and Safety of a Standardized Soy and Hop Extract on Menopausal Symptoms: A 12-Week, Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Objectives: Soy and hop extracts have been investigated as alternatives for hormone replacement therapy. However, their combined efficacy is not known. We investigated the efficacy and safety of a combined soy and hop extract on postmenopausal symptoms. Design: Double-blinded, randomized controlled trial. Settings/Location: Gynecological outpatient clinic of tertiary hospital. Subjects: Seventy-eight women with moderate or severe menopausal symptoms assessed as modified Kupperman Menopoausal Index (KMI) scores >20. Interventions: They received either a combined soy and hop extract (n = 38) or placebo (n = 40). Outcome measures: Menopausal symptoms were evaluated through self-reporting of modified Kupperman Menopausal Index (KMI) scores at baseline and after 6 and 12 weeks. We assessed serum levels of bone metabolism biomarkers, ultrasonographic parameters, hormone profiles, compliance, and safety. Results: After 12 weeks of the treatment, treatment group scores decreased by 20.61 points compared with 14.80 points in the placebo group (p < 0.05). Fatigue, paresthesia, arthralgia, and myalgia, palpitation and vaginal dryness significantly improved more in the treatment group compared with the placebo group after 12 weeks (p < 0.05). Urine N-telopeptide in participants ≥50 years in the treatment group showed a reduced increase. Endometrial thickness and hormonal profiles did not show significant changes in either group. No serious adverse events were reported. Conclusion: The results suggest that 190 mg of combined soy and hop extract is safe and effective for improvement of menopausal symptoms. CRIS No.: KCT0006019.

Adding Soy Protein to Milk Enhances the Effect of Resistance Training on Muscle Strength in Postmenopausal Women

Resistance training (RT) and high-quality protein ingestion improves muscle mass (MM) and strength (MS). However, no study has evaluated the effect of ingesting milk plus soy protein (SOY) on MM and MS in postmenopausal women (PW). Thus, the aim of this study was to evaluate the effects of adding SOY to milk on MM and MS after 16 weeks of RT. Thirty-two PW were randomized and allocated into two groups: placebo and RT (PL+RT, n = 16) and SOY and RT (SOY+RT, n = 16). The SOY+RT received 25 g of SOY while the PL+RT received 25 g of maltodextrin (placebo). All supplements were given in the form of a chocolate-flavored powder added to 200 mL of milk. The RT protocol consisted of eight total body exercises at 70% of one repetition maximum (1RM), three sets of 8-12 repetitions, 2-3 times/week. No differences were found in the baseline measures between groups (age, menopause status, anthropometric and nutrition patterns), except for protein intake, which was higher in the SOY+RT. Both groups increased the MM (bioimpedance) showing no difference between groups (PL+RT = 1.5 kg; SOY+RT = 1.1 kg). For MS, the SOY+RT showed a larger (p < .05) increase in 1RM of bench press (PL+RT = 6.7 kg; SOY+RT = 12.5 kg), knee extension (PL+RT = 3.7 kg; SOY+RT = 6.7 kg), total load (PL+RT = 15.1 kg; SOY+RT = 24.2 kg), and the total load exercises/MM (PL+RT = 0.3 kg; SOY+RT = 0.9 kg). These results suggest that adding SOY to milk combined with 16 weeks of RT resulted in more significant increases in MS in PW.

Modulation of Aromatase by Phytoestrogens

The aromatase enzyme catalyzes the conversion of androgens to estrogens in many human tissues. Estrogens are known to stimulate cellular proliferation associated with certain cancers and protect against adverse symptoms during the peri- and postmenopausal intervals. Phytoestrogens are a group of plant derived naturally occurring compounds that have chemical structures similar to estrogen. Since phytoestrogens are known to be constituents of animal/human food sources, these compounds have received increased research attention. Phytoestrogens may contribute to decreased cancer risk by the inhibition of aromatase enzyme activity and CYP19 gene expression in human tissues. This review covers (a) the aromatase enzyme (historical descriptions on function, activity, and gene characteristics), (b) phytoestrogens in their classifications and applications to human health, and (c) a chronological coverage of aromatase activity modulated by phytoestrogens from the early 1980s to 2015. In general, phytoestrogens act as aromatase inhibitors by (a) decreasing aromatase gene expression, (b) inhibiting the aromatase enzyme itself, or (c) in some cases acting at both levels of regulation. The findings presented herein are consistent with estrogen's impact on health and phytoestrogen's potential as anticancer treatments, but well-controlled, large-scale studies are warranted to determine the effectiveness of phytoestrogens on breast cancer and age-related diseases.

Effects of phytoestrogen supplementation in postmenopausal women with dry eye syndrome: a randomized clinical trial

OBJECTIVE

To evaluate the correlation between tear osmolarity and blood levels of 17-β estradiol, estrone, and testosterone in postmenopausal women with dry eye syndrome, and to assess the efficacy and safety of oral supplementation with phytoestrogens, lipoic acid, and eicosapentaenoic acid in this population.

DESIGN

Cross-sectional study including 66 postmenopausal women with dry eye syndrome.

METHODS

Sixty-six postmenopausal women with dry eye syndrome were enrolled in a randomized, double-blind, placebo-controlled, crossover study. Patients were divided into 2 groups (groups A and B) and treated, respectively, with phytoestrogen (Bioos, Montegiorgio, Italy) tablets or placebo tablets for 30 days. The 2 treatment periods were separated by a 30-day washout. Patients were examined on days 0 and 30 of each period. Assessments included blood levels of sex hormones, the Schirmer test for tear production, and measurement of tear osmolarity and tear film break-up time.

RESULTS

At baseline, all patients had low sex hormone levels, which were correlated with high tear film osmolarity values (r = -0.59,-0.61,-0.58, respectively). After 30 days of therapy, the group treated with Lacrisek® (Bioos) had significantly decreased tear osmolarity (P<0.005) and significantly increased tear production evaluated with the Schirmer test and tear film break-up time values (P<0.001) compared with the placebo-treated group.

CONCLUSIONS

Our study confirms that steroid hormones play an important role in ocular surface equilibrium and functions. Consequently, reduced blood levels of these hormones can produce changes at the ocular surface. Phytoestrogen supplementation can significantly improve the signs and symptoms of dry eye syndrome in postmenopausal women.

Ginsenoside Rg1 protects primary cultured rat hippocampal neurons from cell apoptosis induced by β-amyloid protein

OBJECTIVES

Estrogen is known to prominently benefit neuronal syndromes and neurodegenerative diseases. Ginsenoside Rg1, an active ingredient found in a Chinese plant, ginseng root, was previously demonstrated to exert estrogen-like activity. This study was performed to assess the neuroprotective effect of ginsenoside Rg1 against apoptosis induced by β-amyloid protein 25-35 (Aβ(25-35)) in primary cultured rat hippocampal neuronal cells as well as in the underlying mechanisms.

METHODS

We first measured cell viability and lactate dehydrogenase (LDH) release from primary cultured rat hippocampal neurons. After that, the inhibition effects of ginsenoside Rg1 on neuronal cell apoptosis were evaluated with flow cytometric analysis. Furthermore, western blot analysis was used for detecting the expression of apoptosis-related proteins Bcl-2, Bax, and active caspase 3.

RESULTS

The results show that ginsenoside Rg1 could increase neuronal viability and reduce LDH release; rescue cell apoptosis induced by Aβ(25-35); decrease the expression of caspase 3, increase the ratio of Bcl-2/Bax at the protein levels compared with the cells only treated with Aβ(25-35).

CONCLUSIONS

Taken together, our results indicate that the apoptosis induced by Aβ(25-35) could be reversed by ginsenoside Rg1. Furthermore, this neuroprotective effect is probably mediated by up-regulating the ratio of Bcl-2/Bax that activates caspase 3.

Effects of resistance training and soy isoflavone on body composition in postmenopausal women

Objective. To investigate the independent and additive effects of resistance training (RT) and soy isoflavone (ISO) on body composition in postmenopausal women (PW). Method. This study used a placebo-controlled, double-blind (soy), randomized (ISO versus placebo) × (RT versus No RT) design. A total of 80 PW, aged 45–70 years, were randomly (71 completed 9-months intervention): RT + ISO (n = 15), No RT + ISO (n = 20), RT + placebo (n = 18), and No RT + placebo (n = 18). ISO received 100 mg a day of isoflavone; and to RT attended supervised resistance training sessions. At baseline and 9-months, fat and muscle mass were estimated by DXA. ANOVA and test t were used. Results. RT groups showed significantly increased muscle strength (35.2%) and muscle mass (1.4%). Exercising attenuated gains in fat trunk and % body fat (P < .05). Significant decreases in muscle mass (−1.8%) and increases in fat mass of the whole-body (1.6%) and trunk (9.7%) was found in no-RT groups (P < .05). In ISO groups, there were no differences in body composition and muscle strength. ISO and RT had no additive effects. Conclusion. In PW: RT improved muscle mass and strength and attenuated gain of fat mass; ISO did not alter body composition and muscle strength; there were no additive effects of RT and ISO.

Ginsenoside Rg1 exerts estrogen-like activities via ligand-independent activation of ERalpha pathway

Ginsenoside Rg1, an active ingredient commonly found in ginseng root, was previously demonstrated to be a phytoestrogen that exerted estrogen-like activity without direct interaction with estrogen receptors (ERs) in human breast cancer (MCF-7) cells. The present study was designed to determine the molecular mechanism by which Rg1 exerted estrogenic effects. Co-incubation of MCF-7 cells with 1 microM of ER antagonist ICI182780 abolished the inductive effects of Rg1 on pS2 expression as well as ERE-luciferase activity, suggesting that the estrogenic effects of Rg1 were mediated through the endogenous ERs. To evaluate the relative involvement of ERalpha and ERbeta in mediating the actions of Rg1, ER-negative human embryonic kidney (HEK293) cells were co-transfected with the ERE-luciferase reporter construct and either ERalpha or ERbeta construct. The results showed that Rg1 could activate ERE-luciferase activity via the ERalpha-mediated pathway in a dose-dependent manner (10(-14) to 10(-6)M); whereas, the activation of ERbeta-mediated ERE-luciferase activity by Rg1 only occur at high concentration (10(-6)M). Furthermore, the results showed that 1pM Rg1 could rapidly induce phosphorylation of the AF-1 domain of ERalpha at serine 118 residue within the first 5 min of incubation, suggesting that Rg1 activates ERalpha in a ligand-independent manner. Taken together, our results indicate that Rg1 preferentially activates ERalpha via phosphorylation of AF-1 domain in the absence of receptor binding. This study is the first to provide evidence that ginsenoside Rg1 exerts estrogen-like actions via ligand-independent activation of ERalpha pathway.

Effects of isoflavones on the coagulation and fibrinolytic system of postmenopausal women

OBJECTIVE

We evaluated the effects of soy isoflavone supplementation on hemostasis in healthy postmenopausal women.

METHODS

In this double-blinded, placebo-controlled study, 47 postmenopausal women 47-66 y of age received 40 mg of soy isoflavone (n = 25) or 40 mg of casein placebo (n = 22) once a day for 6 mo. Levels of factors VII and X, fibrinogen, thrombin-antithrombin complex, prothrombin fragments 1 plus 2, antithrombin, protein C, total and free protein S, plasminogen, plasminogen activator inhibitor-1, and D-dimers were measured at baseline and 6 mo. Urinary isoflavone concentrations (genistein and daidzein) were measured as a marker of compliance and absorption using high-performance liquid chromatography. Baseline characteristics were compared by unpaired Student's t test. Within-group changes and comparison between the isoflavone and casein placebo groups were determined by a mixed effects model.

RESULTS

The levels of hemostatic variables did not change significantly throughout the study in the isoflavone group; however, the isoflavone group showed a statistically significant reduction in plasma concentration of prothrombin fragments 1 plus 2; both groups showed a statistically significant reduction in antithrombin, protein C, and free protein S levels. A significant increase in D-dimers was observed only in the isoflavone group. Plasminogen activator inhibitor-1 levels increased significantly in the placebo group. However, these changes were not statistically different between groups.

CONCLUSION

The results of the present study do not support a biologically significant estrogenic effect of soy isoflavone on coagulation and fibrinolysis in postmenopausal women. However, further research will be necessary to definitively assess the safety and efficacy of isoflavone.

Efficacy and safety of a soy isoflavone extract in postmenopausal women: a randomized, double-blind, and placebo-controlled study

OBJECTIVE

To investigate the efficacy of soy isoflavone on climacteric symptoms in postmenopausal women.

DESIGN

In this double-blind, randomized, placebo-controlled study, a total of 80 women (mean age = 55.1 years), who reported 5 or more hot flush episodes per day, were randomized to receive either 250 mg of standardized soy extract (Glycine max AT) a total of 100mg/day of isoflavone (n = 40) or placebo (n = 40). Exclusion criteria included: contra-indication for hormone therapy (HT), chronic gastrointestinal diseases, and users of HT within the preceding 6-months. For 10-months, climacteric symptoms were evaluated using a score card and the menopausal Kupperman index. Compliance and safety were also assessed. At baseline and the end of the study, lipid and hormonal profiles, as well as vaginal, mammographic and ultrasonographic parameters were measured. The t-test, Wilcoxon test and ANOVA were used in the statistical analysis.

RESULTS

At baseline, the mean number of hot flushes was 9.6 +/- 3.9 per day in the isoflavone group and 10.1+/-4.9 in the placebo group (p>0.05). After 10 months, there was a significant reduction in frequency of hot flushes among isoflavone users when compared to those on placebo (3.1 +/- 2.3 and 5.9 +/- 4.3, respectively) (p<0.001). Kupperman index mean values showed a significant reduction in both groups. However, soy isoflavone was significantly superior to placebo, in reducing hot flush severity (69.9% and 33.7%, respectively) (p<0.001). Endometrial thickness, mammography, vaginal cytology, lipids and hormonal profile did not change in both groups. No serious adverse event related to isoflavone treatment was reported.

CONCLUSIONS

The soy isoflavone extract exerted favorable effects on vasomotor symptoms and good compliance, providing a safe and effective alternative therapeutic for postmenopausal women.

Efficacy on menopausal neurovegetative symptoms and some plasma lipids blood levels of an herbal product containing isoflavones and other plant extracts

OBJECTIVES

To assess the efficacy of a product containing isoflavones and other plant extracts (BIO) on whole menopausal symptomatology and plasma lipids profile.

METHODS

Multicentre, randomized, double blind, placebo controlled clinical investigation on 125 menopausal women randomly assigned to two groups treated for 6 months with placebo or one tablet daily of an herbal product containing 72 mg/dose of isoflavones of different plants origin and other plant extracts (BIO). Primary end-point: Kupperman Menopause Index (KI) variations; secondary end-point: activity on plasma lipids profile and clinical global impression (CGI) on efficacy and tolerability by investigators and patients. The usual parametric test (paired Student t test) was performed to evaluate the significance. In case of non-applicability of parametric tests, the non-parametric Mann-Whitney U test was used. The differences where considered significant at p<0.05 level.

RESULTS

At the end of treatment in both groups KI showed a significant decrease (p<0.001). However, in the BIO group the KI reduction was significantly higher (p=0.0265) than in the placebo group after 4 and 6 months of treatment. In the BIO treated patients the LDL cholesterol showed a borderline but not significant reduction compared to placebo (p=0.0608) and triglyceride (TG) a significant (p=0.0151) decrease compared to placebo. The investigator's and patient's CGI on BIO group where superior as compared to placebo. Clinical tolerability was good in booth groups.

CONCLUSION

On the basis of positive effects on KI and lipids profile as well as of good clinical tolerability, BIO can be considered one of the possible alternative therapy for conventional HRT.

Effects of soy protein and resistance exercise on body composition and blood lipids in postmenopausal women

OBJECTIVE

To assess the effect of soy protein and progressive resistance training on body composition and lipids in postmenopausal women.

DESIGN

In a controlled trial, 46 postmenopausal women were randomized to one of four groups: 25 g of soy protein (SP, n=10), 25 g of soy protein plus resistance exercise (SPE, n=14), 25 g of maltodextrine (placebo) (PL, n=11), or placebo plus resistance exercise (PLE, n=11). Progressive resistance training was held three times a week for 16 weeks and included 8 exercises (3 series of 8-12 repetitions). At baseline and after 16 weeks, body mass index, waist circumference (WC), body fat, muscle mass and serum lipid levels were measured. To confirm isoflavone absorption, urinary concentrations were determined. The t-test of Student and ANOVA were used in the statistical analysis.

RESULTS

Subjects were classified as overweight and showed android fat distribution. Urinary isoflavone excretion indicated compliance to soy protein treatment. After 16 weeks of intervention, both SPE and PLE groups showed a significant increase of 1.3 kg in muscle mass and reduction in WC of -1.4 and -2.1cm, respectively (p<0.05). Significant decreases in the mean values of total cholesterol and LDL (-29.0 and -24.0 mg/dL, p<0.001 and p<0.006, respectively) were observed in the users of soy protein alone (SP).

CONCLUSIONS

Soy protein supplementation did not influence the indicators of body composition. However, it exerted possible favorable effects on lipid profile in postmenopausal women. The increase in muscle mass and reduction in abdominal fat were correlated with resistance training.

Benefits of soy germ isoflavones in postmenopausal women with contraindication for conventional hormone replacement therapy

OBJECTIVE

To evaluate the effects of isoflavones on vasomotor symptoms and blood lipids in postmenopausal women with contraindication for conventional hormone replacement therapy (HRT).

METHODS

This prospective, double-blind and placebo-controlled study included 50 postmenopausal women randomly divided into two groups: 25 women on soy germ isoflavones (60 mg per day, capsules) and 25 women on placebo. Inclusion criteria included: non-vegetarian, non-asian women whose last menstruation dated at least 12 months prior to the beginning of the study, with FSH > 40 mIU/ml, hot flushes and contraindication for HRT, not using tamoxifen or antibiotic and no disease of the gastrointestinal tract. For 6 months, the Kupperman menopausal index (KMI), the vaginal cytological maturation value (MV) and both hormonal and lipid profiles were assessed. The t-test and analysis of variance (ANOVA) were employed to compare the two groups.

RESULTS

In both groups, a decreased KI rate was observed. However, isoflavone was significantly superior to placebo in reducing hot flushes (44% versus 10%, respectively) (P < 0.05). After 6 months, the isoflavone group showed increased estradiol levels with unchanged FSH, LH, and vaginal cytology, and a reduction of 11.8% in LDL and an increase of 27.3% in HDL (P < 0.05 ). In the placebo group, just a reduction in MV was observed after 6 months (P < 0.05 ).

CONCLUSIONS

Soy germ isoflavone exerted favorable effects on vasomotor symptoms and lipid profile, showing itself to be an interesting alternative therapy for the postmenopausal women with contraindication for conventional HRT.

Phytoestrogens: hormonal action and brain plasticity

Because of their protective effects in age-related diseases and hormone-dependent cancers, the use of phytoestrogens (isoflavones) as 'natural' remedies has gained prominence. Isoflavones are estrogen mimics that bind estrogen receptors and act like natural selective estrogen receptors modulators. However, limited data exists regarding the influence of soy-derived dietary isoflavones in brain. This brief review will address these topics and examine the influence of dietary isoflavones on sexually dimorphic hypothalamic nuclei. We have observed that altering the isoflavone content within diet significantly affects both the sexually dimorphic nucleus of the preoptic area (a structure that is larger in males than in females) and the anteroventral periventricular nucleus (a structure that is larger in females than in males). Specifically, when animals were switched from phytoestrogen-rich to a phytoestrogen-free diet the volume of the sexually dimorphic nucleus of the preoptic area was decreased in males (no alterations were detected in females). Conversely, when the anteroventral periventricular nucleus was examined, volume changes were recorded in males and females opposite to the patterns observed for the sexually dimorphic nucleus of the preoptic area. Given the practical limitations of examining the effects of dietary phytoestrogens in the human brain, it is important to establish comparative data sets to elucidate phytoestrogen's hormone action and potentially its beneficial brain health effects.

Estrogenic and anticarcinogenic properties of kurarinone, a lavandulyl flavanone from the roots of Sophora flavescens

Kurarinone, a lavandulyl flavanone, was isolated from a polyphenolic extract of the roots of Sophora flavescens using fractionation guided by estrogenic activity, which was determined by recombinant yeast and Ishikawa Var-I bioassays. Kurarinone showed weak estrogenic activity both in the yeast screen and in the Ishikawa Var-I assay with EC(50) values of 4.6 and 1.66 microM, respectively. Furthermore, kurarinone was found to have potent cytotoxic activity (IC(50) value = 22.2 microM) against human MCF-7/6 breast cancer cells in the sulforhodamine-B assay.

Inhibition of serotonin re-uptake by licorice constituents

Ovarian steroid hormones, estrogen and progestin, affect the function of the serotonin neural system by inhibiting serotonin re-uptake through allosteric interaction with the serotonin transporter (SERT) in a nongenomic mechanism. Blocking or reducing serotonin re-uptake at the synapse alleviates depression. The aim of this study was to test the effect of compounds of the isoflavan and isoflavene groups, subclasses of the flavonoids family, on serotonin re-uptake and to compare the results with the effect of other known phytoestrogens like genistein and daidzein to relate the activity of these compounds to their structure. The effect of these compounds on the re-uptake of radioactive serotonin was assayed in HEK-293 cells stably expressed the recombinant human serotonin transporter (hSERT). The results demonstrated that the isoflavans glabridin and 4'-O-methylglabridin (4'-OMeG) and the isoflavene glabrene inhibited serotonin re-uptake by 60, 53 and 47%, respectively, at 50 microM, whereas resorcinol, the isoflavan 2'-O-methylglabridin (2'-OMeG), and the isoflavones genistein and daidzein were inactive. The inhibition of serotonin re-uptake is dose dependant with glabridin and estradiol. These results emphasize the importance of the lipophilic part of the isoflavans, as well as the hydroxyl at position 2' on ring B. In conclusion, this study showed that several isoflavans are unique phytoestrogens, which like estradiol, affects the serotonergic system and inhibits serotonin re-uptake and, thus, potentially may be beneficial for mild to moderate depression in pre- and postmenopausal women.

Efficacy and safety of a phytoestrogen preparation derived from Glycine max (L.) Merr in climacteric symptomatology: a multicentric, open, prospective and non-randomized trial

A multicentric, open, prospective, observational and no-randomized clinical trial was carried out in Spain with 190 postmenopausal women receiving a soy preparation rich in isoflavones (PHYTO SOYA, capsules containing 17.5 mg isoflavones). The main object of the present study was to investigate its efficacy in alleviating the symptomatology derived from the lack of estrogen, mainly hot flushes, but also other symptoms such as sleep disorder, anxiety, depression, vaginal dryness, loss of libido and bone pain. Each patient received 35 mg isoflavones per day in two doses. During the four months' treatment, a statistically significant decrease in the number of hot flushes with PHYTO SOYA was experienced by 80.82% women; only 5,48% patients did not improve with the treatment. The average reduction was 47.8%, which is equivalent to 4 hot flushes. All the other studied parameters also showed a statistically significant decrease. No severe side-effects were reported and tolerance was excellent. Treatment with PHYTO SOYA resulted in a significant improvement of the symptomatology that accompanies the lack of estrogen during menopause.