Phytoestrogen therapy for menopausal symptoms?

Effect of hyperoside on osteoporosis in ovariectomized mice through estrogen receptor α/ITGβ3 signaling pathway

Osteoporosis is a highly prevalent bone metabolic disease in menopause due to estrogen deficiency. Hyperoside is a main compound in Semen cuscutae. Our team previously reported that Semen cuscutae has anti osteoporosis effect on ovariectomized mice by inhibiting bone resorption of osteoclasts. However, it is still unclear whether hyperoside affects osteoclast differentiation and bone resorption, and whether its anti-osteoporosis effect is related to an estrogen-like effect. This study investigates the potential mechanism of hyperoside's anti-osteoporotic effect by examining its impact on osteoclast differentiation and its relationship with the estrogen receptor. DXA, Micro-CT, TRAP staining, HE, and ELISA were used to assess the impact of hyperoside on OVX-induced osteoporosis. The effect of hyperoside on octeoclast differentiation was evaluated using TRAP activity assay, TRAP staining, F-actin staining. The activation of the estrogen receptor by hyperoside and its relationship with osteoclast differentiation were detected using dual-luciferase reporter assay and estrogen receptor antagonists. Our findings revealed that hyperoside (20-80 mg/kg) protect against OVX-induced osteoporosis, including increasing BMD and BMC and improving bone microstructure. Hyperoside inhibited osteoclast differentiation in a concentration dependent manner, whereas estrogen receptor α antagonists reversed its inhibitory effect osteoclast differentiation. Western blot results suggested that hyperoside inhibited TRAP, RANKL, c-Fos and ITG β3 protein expression in osteoclast or femoral bone marrow of ovariectomized mice. Our findings suggest that hyperoside inhibits osteoclast differentiation and protects OVX-induced osteoporosis through the ERα/ITGβ3 signaling pathway.

Comparative Analysis of Over-the-Counter Tablet Preparations of Isoflavones Extracted from Soy Available in Portugal

The results of a survey of 28 over-the-counter tablet preparations of isoflavones extracted from soy and 2 with black cohosh that are available in Portuguese pharmacies are presented. All were remedies for hot flushes and post-menopause related problems. Their isoflavone content was analysed by HPLC/DAD and LC/MS-MS. The results show that the isoflavonoids in soy extracts sold by the pharmaceutical companies in Portugal are mainly daidzin, glycitin and genistin.

Scientific Papers and Patents on Substances with Unproven Effects. Part 2

Several examples are discussed in this review, where substances without proven effects were proposed for practical use within the scope of evidence-based medicines. The following is discussed here: generalizations of the hormesis concept and its use in support of homeopathy; phytoestrogens and soy products potentially having feminizing effects; glycosaminoglycans for the treatment of osteoarthritis and possibilities of their replacement by diet modifications; flavonoids recommended for the treatment of chronic venous insufficiency and varicose veins; acetylcysteine as a mucolytic agent and its questionable efficiency especially by an oral intake; stem cells and cell therapies. In conclusion, placebo therapies can be beneficial and ethically justifiable but it is not a sufficient reason to publish biased information. Importantly, placebo must be devoid of adverse effects, otherwise, it is named pseudo-placebo. Therapeutic methods with unproven effects should be tested in high-quality research shielded from the funding bias. Some issues discussed in this review are not entirely clear, and the arguments provided here can initiate a constructive discussion.

Comparative Effects of Estrogen and Phytoestrogen, Genistein on Testicular Activities of Streptozotocin-Induced Type 2 Diabetic Mice

The aim of this study was to compare the effect of synthetic estrogen (E2) with a phytoestrogen and genistein in ameliorating type 2 diabetes mellitus (T2D)-mediated testicular dysfunction in mice. The streptozotocin (STZ)-induced type 2 diabetic mice were treated exogenously with either E2 or genistein for 2 durations and compared their effects on testicular activities, serum glucose, and insulin level. Type 2 diabetic mice treated with E2 for only short term (14 days) improved regressive changes in the testicular histology by increasing testosterone synthesis and improving insulin sensitivity, whereas those treated for longer duration (28 days) failed to improve testicular dysfunctions. On the other hand, genistein treated for both short- and long term was useful in improving T2D-induced adverse effects on testicular functions. This study further suggests that treatment with genistein improves spermatogenesis in type 2 diabetic mice by increasing insulin-induced formation of lactate and antioxidative enzymes, which contributes to prevent germ cell apoptosis. Thus, genistein can be used to ameliorate T2D-induced testicular dysfunction.

Soy and phytoestrogens: possible side effects

Phytoestrogens are present in certain edible plants being most abundant in soy; they are structurally and functionally analogous to the estrogens. Phytoestrogens have been applied for compensation of hormone deficiency in the menopause. At the same time, soy products are used in infant food and other foodstuffs. Furthermore, soy is applied as animal fodder, so that residual phytoestrogens and their active metabolites such as equol can remain in meat and influence the hormonal balance of the consumers. There have been only singular reports on modified gender-related behavior or feminization in humans in consequence of soy consumption. In animals, the intake of phytoestrogens was reported to impact fertility, sexual development and behavior. Feminizing effects in humans can be subtle and identifiable only statistically in large populations.

Exogenous hormonal regulation in breast cancer cells by phytoestrogens and endocrine disruptors

Observations on the role of ovarian hormones in breast cancer growth, as well as interest in contraception, stimulated research into the biology of estrogens. The identification of the classical receptors ERα and ERβ and the transmembrane receptor GPER and the resolution of the structure of the ligand bound to its receptor established the principal molecular mechanisms of estrogen action. The presence of estrogen-like compounds in many plants used in traditional medicine or ingested as food ingredients, phytoestrogens, as well as the estrogenic activities of many industrial pollutants and pesticides, xenoestrogens, have prompted investigations into their role in human health. Phyto- and xenoestrogens bind to the estrogen receptors with a lower affinity than the endogenous estrogens and can compete or substitute the hormone. Xenoestrogens, which accumulate in the body throughout life, are believed to increase breast cancer risk, especially in cases of prenatal and prepuberal exposure whereas the role of phytoestrogens is still a matter of debate. At present, the application of phytoestrogens appears to be limited to the treatment of post-menopausal symptoms in women where the production of endogenous estrogens has ceased. In this review we discuss chemistry, structure and classification, estrogen signaling and the consequences of the interactions of estrogens, phytoestrogens and xenoestrogens with their receptors, the complex interactions of endogenous and exogenous ligands, the evaluation of the health risks related to xenoestrogens, and the perspectives toward the synthesis of potent third generation selective estrogen receptor modulators (SERMs).

The use of herbal preparations to alleviate climacteric disorders and risk of postmenopausal breast cancer in a German case-control study

BACKGROUND

The use of herbal preparations (HEP) to alleviate climacteric disorders is expected to increase as women seek alternatives to menopausal hormone therapy to avoid the associated breast cancer risk. Data are sparse on the long-term effects of HEP containing phytoestrogens and black cohosh on breast cancer risk.

METHODS

Within a German case-control study, associations between patterns of HEP use and incident breast cancer were investigated in 10,121 postmenopausal women (3,464 cases, 6,657 controls). Information on HEP use was collected in face-to-face interviews supported by a list of brand names. Multivariate logistic and polytomous regression analyses were done.

FINDINGS

Ever use of HEP (9.9%) was inversely associated with invasive breast cancer [odds ratio (OR), 0.74; 95% confidence interval (CI), 0.63-0.87] in a dose-dependent manner (OR, 0.96 per year of use; P = 0.03). Classes of HEP did not differ significantly (P(heterogeneity) = 0.81). Risks for invasive ductal (OR, 0.72; 95% CI, 0.60-0.87) and combined lobular/mixed/tubular tumors (OR, 0.76; 95% CI, 0.58-1.01) were similarly reduced by any HEP use but not for in situ carcinomas (1.34; 95% CI, 0.86-2.09). There were no substantial differences in associations of HEP use by estrogen receptor status (ER(+) OR, 0.74; 95% CI, 0.62-0.89; ER- OR, 0.68, 95% CI, 0.50-0.93) and progesterone receptor status of the tumor.

INTERPRETATION

Our findings support the hypothesis that HEP use protects from invasive breast cancer in postmenopausal women. Among conceivable modes of action, those independent of estrogen receptor-mediated pathways seem to be involved (i.e., cytotoxicity, apoptosis).

Efficacy of soy isoflavones for depressive symptoms of the climacteric syndrome

OBJECTIVES

To evaluate the efficacy of soy isoflavones extract (SIE) in the treatment of depressive symptoms in women with climacteric syndrome.

METHODS

Placebo-controlled double-blind randomized study with 84 climacteric outpatients attended in the Lauro Wanderley University Hospital in Joao Pessoa (PB), Brazil. In the assessment of the depressive symptoms, the Brazilian version of the Center of Epidemiologic Studies of Depression (CES-D) scale was used, on the pre-treatment visits (VT1), 8th (VT2) and 16th (VT3) weeks after treatment. The experimental group (EG) received the daily dose of 120mg SIE and the control group (CG), placebo. The primary efficacy measure was the comparison of the percent reductions in the CES-D scores from VT1 to VT3 between EG and CG (t-test, p<0.05). The security analysis consisted of laboratory and clinical evaluation of adverse events.

RESULTS

The CES-D scores in the EG reduced from 12.5 (+/-4.2) in VT1 to 9.9 (+/-3.6) in VT2 (VT20.05). In the outcome of the 16-week treatment (VT1-VT3), reduction of the CES-D scores did not reach statistical significance between groups. There were no clinically relevant adverse events attributable to the treatment.

CONCLUSIONS

The treatment with soy isoflavones did not produce significant reduction on the depressive symptoms of a predominantly affective nature evaluated in this study. The symptomatic reduction initially observed was apparently a nonspecific response to treatment, corroborating evidences from the literature on the placebo phenomenon in treatment of the climacteric syndrome.

Pharmacological investigations of the unique herbal formula Menoprogen in rats: estrogenic activity and mechanism

The present study aimed to evaluate the pharmacological effects of Menoprogen in the management of menopausal symptoms for aged female rats. Menoprogen was supplemented to a group of elderly female rats for 8 weeks. Subsequently, histopathological examinations were conducted in the isolated uterine and ovary tissues and pituitary glands of the rats. Serum levels of estradiol (E(2)), progesterone (P), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined. The ultrastructure of the rat ovarian granulocytes was analyzed. The histopathological examinations revealed no statistical difference in the quantity of follicles in the ovary and of acidophil and basophil cells in the anterior pituitary gland of the Menoprogen-fed rats versus healthy normal rats. Moreover, the cellular morphogenesis was in a healthy state for the Menoprogen-fed rats. Menoprogen significantly increased the levels of serum E(2) and P but reduced FSH and LH levels. The electron microscopic analysis showed that Menoprogen significantly retarded apoptosis of the ovarian granulocytes of the rats. Further investigation of Menoprogen for the alternative treatment of menopausal symptoms is warranted.

Serum cholesterol efflux potential in postmenopausal women treated with isolated isoflavones

OBJECTIVE

Based on the low cardiovascular risk in Asian populations, phytoestrogens are believed to provide vascular benefits. To elucidate the mechanisms behind the possible cardiovascular effects of phytoestrogens, we evaluated reverse cholesterol transport by assessing the capacity of serum to promote cholesterol efflux in postmenopausal women treated with isolated isoflavones.

DESIGN

Thirty postmenopausal women were treated in a randomized, placebo-controlled, crossover trial with isoflavones or placebo for 3 months interrupted by a 2-month washout period. Serum samples were collected before and after each treatment period, and the cholesterol efflux potential was investigated by using H-cholesterol--labeled Fu5AH cells in culture.

RESULTS

Serum promoted 20.2% +/- 3.0% and 19.9% +/- 3.4% (mean +/- SD) cholesterol efflux after isoflavonoid treatment and after placebo treatment, respectively. Thus, the isoflavone treatment did not affect serum cholesterol efflux. We also studied separately women who produced high concentrations of the isoflavone metabolite equol into serum because some studies suggest that equol could exert favorable vascular effects. However, there was no difference in serum cholesterol efflux capacity between the equol producers (n = 15) and non-equol producers (n = 15).

CONCLUSIONS

In conclusion, isoflavone treatment did not affect serum cholesterol efflux potential in postmenopausal women. Based on our findings, isolated isoflavones do not provide vascular benefits by improving cholesterol efflux.

Isoflavones and postmenopausal women: a critical review

Isoflavonic phytoestrogens, or isoflavones, constitute a class of phytoestrogens that have properties similar to selective estrogen receptor modulators, and have attracted a substantial degree of attention in recent years, particularly as a possible alternative to the conventional hormone replacement therapy regimens used by postmenopausal women. Despite great promise, it is difficult to make many specific recommendations about their use at the current time, in light of the many outstanding questions that hopefully will be answered in the future by focused interventional studies involving humans. Studies to date indicate that the use of isoflavones to address vasomotor symptoms provides at most small benefits beyond a placebo effect, and no benefit for genital atrophy. As for postmenopausal women whose primary concern is cardiovascular disease, the recommendation of the American Heart Association to include soy protein foods as part of an otherwise healthy diet is well justified, and similarly the substitution of supplements containing soy protein for animal protein can also be recommended. The use of purified isoflavone supplements not containing soy protein may have some cardiovascular benefits, but these appear to be less substantial in degree than those provided by soy protein with isoflavones. In particular, more research is needed to assess the effects of isoflavones on osteoporosis, for which no recommendation regarding isoflavones can be made based on the current data. Also, isoflavones should not be taken by postmenopausal women for the specific purpose of decreasing their risk of breast or endometrial cancer, although, at least for those without pre-existing disease or at high risk, it seems quite unlikely that isoflavone use is harmful in this regard.

An evaluation of the contents and quality of menopause information on the World Wide Web

OBJECTIVE

To evaluate the content and quality of currently available World Wide Web based information about menopause.

DESIGN

A sample of the 100 top sites obtained with the search engine Google for the key word "menopause" was evaluated according to predefined general and specific criteria, content type, language, and quality. The Internet popularity was established by the number of links to each website. Using a systematic scoring tool each site was assessed on factual information provided and quality of site.

RESULTS

The websites studied were heterogeneous in content and quality. The most frequent type of website has commercial content with low quality, biased or useless information. Few sites provided comprehensive medical information about menopause. The scientific societies not always provided complete information about the possible adverse events related with hormone replacement therapy. The results of the Women's Health Initiative (WHI) and the Million Women (MW) studies are discussed by very few websites. Internet popularity did not correlate with measures of quality such as display of authorship, attribution or references, currency of information, and disclosure.

CONCLUSION

The content and quality of the websites concerning menopause are widely varied and sometimes biased to commercial goals. The dominant medical information is of low quality and do not comply with general quality scores although the most informative sites have comprehensive content about the menopause including the recent results of the WHI and MW studies.

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.

Endocrine and cognitive effects of short-time soybean consumption in women

BACKGROUND

Soy phytoestrogens are known to influence the hormonal status acting as partial estrogen agonists. Soy-derived food supplements are advised for hormone replacement therapy, prevention of atherosclerosis, age-related cognitive decline and even hormone-dependent cancer, although results from clinical studies are controversial. Whether increased soybean intake can affect the endocrine status and cognitive abilities is largely unknown.

AIM

To observe the effects of 1 week of increased soybean intake on sex hormone levels and spatial cognitive abilities in women.

SUBJECTS AND METHODS

16 young healthy female volunteers were asked to eat 900 g of soybeans within 1 week. Salivary testosterone (T), free and total plasma T, salivary and plasma estradiol (E) were measured by radioimmunoassay before and after the study period. Mental rotation (MR) and spatial visualization (SV) psychological tests were done at the days of sampling.

RESULTS

Soybean intake increased total plasma T levels (p < 0.02) while decreasing salivary T (p < 0.01) and not altering free plasma T levels. Salivary and plasma E levels were not changed. The results of MR and SV tests were improved after the study period.

CONCLUSION

Short-time increased soybean intake alters the level of total plasma and salivary T and improves spatial cognition in women. Whether this effect is mediated by modulation of estrogen receptors, changes in sex hormone-binding globulin production or changes in activity of steroid-competent enzymes needs further study.

Hormone replacement therapy in postmenopausal women

BACKGROUND

For many years, hormone replacement therapy (HRT) was considered an effective method of restoring the relative protection from coronary artery disease enjoyed by premenopausal women compared with men of similar age. This view has been supported by a substantial number of basic science and observational studies.

DATA SOURCES

Results of recent randomized controlled trials have seriously challenged the concept of the protective value of HRT by showing that rather than decreasing the risk of coronary artery disease, HRT actually appears to increase it. In addition, it increases the risk for breast cancer, stroke, venous thromboembolism, and cholecystitis.

RESULTS

Despite some benefits such as increased bone mineral density and decreased risk of fracture and colorectal cancer, these data suggest that the risks of HRT outweigh the benefits.

CONCLUSIONS

HRT is no longer routinely recommended for prevention of chronic disease. We present the current scientific data, benefits, risks, and consequent clinical recommendations regarding HRT use in postmenopausal women.

Herbal product use and menopause symptom relief in primary care patients: a MetroNet study

OBJECTIVES

The four study objectives were to determine (1) the prevalence of use of four herbal product types promoted to reduce menopause symptoms (phytoestrogens, St. John's wort, Ginkgo biloba, and ginseng) among primary care patients approaching or in menopause, (2) the extent to which women who use these types of herbal products report menopause-related symptoms compared with herbal product nonusers, (3) the frequency of reported symptom reduction after use, and (4) if use was disclosed to their physicians.

METHODS

A cross-section of ethnically diverse women 40-55 years of age (35.5% African American, 60.2% Caucasian) who were recruited from eight primary care centers in Michigan to complete a self-report survey. The questionnaire included demographic items, health history, recent use of four herbal product types purported to relieve menopause symptoms and perception of symptom improvement, and interest in additional herbal product information.

RESULTS

Of 397 women, 24.9% reported taking, in the previous 6 months, at least one of the four study herbs. Herbal product use did not vary by patient demographics or health characteristics. Herbal product users reported more menopause symptoms than nonusers, and 68% of the users said that the herbs improved their symptoms; 56.4% said that their physician was aware of their herbal product use.

CONCLUSIONS

Primary care patients experiencing common menopausal symptoms are likely to use herbal products that are purported to provide menopause symptom relief, and many believe that these products improve their menopausal symptoms. Healthcare providers should be aware of patient's positive attitude, use patterns, and lack of disclosure of use of herbal medicines. Inquiry of herbal product use is another way for physicians to learn about patient self-medication of bothersome symptoms.

Oestrogen receptor-beta and neurohypophysial hormones: functional interaction and neuroanatomical localisation

Oestrogens affect fluid balance, influencing both ingestive behaviour and renal excretion. The renal effects are partly due to altered release of vasopressin and oxytocin. This study was designed to explore the role of oestrogen receptor-beta (ERbeta) in neurohypophysial hormonal function. Following dietary administration, soya isoflavones reach the brain in sufficient concentration to activate ERbeta, but not oestrogen receptor-alpha (ERalpha). ERbeta function was therefore manipulated by feeding rat diets differing in soya isoflavone content. Fluid balance and neurohypophysial hormone release were measured in male rats maintained for 14 days on a soya isoflavone-free diet or one containing 150 microg/g genistein+daidzein. Food and water intake, body weight, urine flow, osmolality and sodium concentrations were determined daily. After 14 days, plasma and urine osmolality and sodium, vasopressin and oxytocin concentrations were determined. There was no significant difference in weight gain between the two groups or in their excretion of sodium and water or plasma sodium and plasma oxytocin. However, plasma vasopressin was significantly lower in the iso-free group. Double-label immunocytochemistry was used to assess colocalisation of ERbeta with the neurohypophysial hormones in male rats. Cell nuclei showing ERbeta immunoreactivity were abundant in the posterior magnocellular paraventricular nucleus (PVNpm) and in the supraoptic nucleus (SON). Vasopressin-immunoreactive neurones were similarly distributed, forming the core of the PVNpm and the ventral portion of the SON; majority were positive for ERbeta. Cells with oxytocin immunoreactivity were located mainly at the periphery of the PVNpm and in the dorsal SON; only approximately a quarter of these cells showed ERbeta immunoreactivity. Thus, the difference in the effects of the soya diet on vasopressin and oxytocin release may be related to the ERbeta-activating properties of this diet and to the preponderance of this receptor in vasopressin as opposed to oxytocin cells.

Comparison of Pueraria lobata with hormone replacement therapy in treating the adverse health consequences of menopause

OBJECTIVE

Pueraria lobata (PL) is used as a traditional Chinese herbal remedy for menopausal symptoms, as well as an ingredient in preparations for conditions affecting menopausal women, such as osteoporosis, coronary heart disease, and some hormone-dependent cancers. The scientific basis for its action may be its action as a phytoestrogen.

DESIGN

To examine the effects of PL in comparison with hormone replacement therapy (HRT) on lipid profile, sex hormone levels, bone turnover markers, and indices of cognitive function. For the study, 127 community-living, postmenopausal women aged 50 to 65 years were randomized to receive HRT (n = 43), PL (equivalent to 100 mg isoflavone; n = 45), or no treatment (n = 39) for 3 months. The following measurements were carried out at baseline and after 3 months for all participants: menopausal symptoms questionnaire; neuropsychological tests covering memory, attention, motor speed, and word-finding ability; quality of life (SF36); lipid profile; urinary deoxypyridinoline; dietary phytoestrogen intake and urinary phytoestrogen; estradiol; follicle-stimulating hormone; and luteinizing hormone.

RESULTS

Only participants in the HRT group showed a mean reduction in cholesterol and low-density lipoprotein cholesterol that was significantly different from that of the control group. No significant changes in lipid profile or follicle-stimulating hormone and luteinizing hormone were observed in the PL group compared with the controls. However, both the HRT and PL groups showed an improvement in Mini-Mental State Examination score and attention span compared with the case of participants receiving no treatment. HRT and PL had different effects on cognitive function; HRT improved delayed recall, whereas flexible thinking seemed improved in the PL group.

CONCLUSIONS

This study was unable to demonstrate a scientific basis for the use of PL for improving the health of postmenopausal women in general. However, the effect of PL on cognitive function deserves further study.

Phyto-oestrogens

Phyto-oestrogens are oestrogenic compounds found in plants and consist of isoflavones, lignans and coumestans. Epidemiological studies provide evidence for a protective role of isoflavones, and to a lesser extent lignans, against the development of numerous chronic diseases, including several cancers, cardiovascular disease and osteoporosis. The structural similarity of phyto-oestrogens to endogenous oestrogens has prompted the hypothesis that phyto-oestrogens exert hormonal or anti-hormonal effects relevant to the risk of hormone-dependent disease and/or their suitability as a dietary alternative to hormone replacement therapy. The many human studies that have evaluated the effects of isoflavones and lignans on various endpoints relating to risk of various diseases have greatly increased knowledge of how these compounds behave. At the same time, additional questions have been generated. For example, the increasing interest in extracting isoflavones from the soybean for incorporation into dietary supplements has raised important concerns regarding safety and efficacy. Overall, it is clear that phyto-oestrogens are an area of active and advancing research with great potential to continue to affect human health.

Pharmacology of Cimicifuga racemosa extract BNO 1055 in rats: bone, fat and uterus

OBJECTIVES

Hormone replacement therapy (HRT) has therapeutic effects on climacteric complaints and prevents osteoporosis. Owing to the increased risks of breast cancer and cardiovascular diseases, patients look for alternatives. Cimicifuga racemosa (CR) preparations might be an alternative, because they proved to reduce climacteric complaints as efficiently as conjugated estrogens without exerting estrogenic effects in the uterus. Whether CR has positive effects on bone and in fat tissue is currently unknown. Therefore, osteoprotective effects of the CR extract BNO 1055 and an influence on fat tissue were studied in ovariectomized rats.

METHODS

Bone mineral density (BMD) of the tibia of ovariectomized (ovx) rats was determined by computer-assisted tomography (CT). CT scans of fat depots were perimetrically quantified. Bone turnover (osteocalcin, crosslaps) and lipocyte activity (leptin) were also determined. Uterine weights were measured and gene expression of estrogen-regulated uterine genes (IGF-1, ERbeta) was determined by RT-PCR.

RESULTS

Treatment of the ovx rats over a period of 3 months with E(2) and the CR extract BNO 1055 showed osteoprotective effects; both significantly reduced the loss of BMD in tibia. Serum osteocalcin levels were significantly reduced by both treatments, whereas only E(2), but not BNO 1055, reduced serum crosslaps. A paratibial fat depot and serum leptin concentration were also significantly reduced. In contrast to E(2), the CR extract showed no effect on uterine weight and gene expression of E(2)-regulated genes.

CONCLUSION

The CR extract BNO 1055 exerted estrogenic effects in the bone (particularly in osteoblasts) and in fat tissue, but not in the uterus of ovx rats. The extract appears to contain rat organ-specific selective estrogen receptor modulators (SERMs), and if these findings can be approved in human it may be an alternative to HRT.

Phytoestrogens for hormone replacement therapy?

Due to some severe side effects "classical" hormone replacement therapy (HRT) is currently being challenged by a therapy with phytoestrogens. Particularly soy and red clover derived isoflavones are advertised as selective estrogen receptor modulators (SERMs) with only desired and no undesired estrogenic effects. Evidence that this is the case however is scarce. Most studies investigating climacteric complaints did not find beneficial effects. A proposed beneficial effect on mammary cancer is unproven. The majority of studies however indicate an antiosteoporotic effect of isoflavones, while putative beneficial effects in the cardiovascular system are questionable due to the fact that estradiol which--like isoflavones--increase HDL and decrease LDL concentrations appear not to prevent arteriosclerosis in the human. In the urogenital tract, including the vagina, soy and red clover derived isoflavones are without effects. Cimicifuga racemosa extracts are traditionally used for the treatment of climacteric complaints. Evidence is now available that the yet unknown compounds in Cimicifuga racemosa extracts prevent climacteric complaints and may also have antiosteoporotic effects.

Diet and environmental carcinogenesis in breast/gynaecological cancers

This paper reports on recent advances on the relation between diet, other environmental factors and breast and gynaecological cancers. Despite considerable research the issue remains still unsettled. The protective effect of a diet rich in vegetables and fruit, and thus selected (antioxidant) micronutrients, is not consistently reported in various studies. The possible relationship between fats and breast and female genital tract neoplasms also remains unconfirmed, while the potential benefits of physical activity remains unquantified. Alcohol appears to be related to the risk of breast cancer and overweight is associated with post-menopausal breast cancer and is strongly related to the risk of endometrial cancer.