AIM:To assess the safety and effect of the supplementation of a patented blend of dietary phytoestrogens and insoluble fibers on estrogen receptor (ER)-β and biological parameters in sporadic colonic adenomas. METHOD...AIM:To assess the safety and effect of the supplementation of a patented blend of dietary phytoestrogens and insoluble fibers on estrogen receptor (ER)-β and biological parameters in sporadic colonic adenomas. METHODS:A randomized, double-blind placebo-controlled trial was performed. Patients scheduled to undergo surveillance colonoscopy for previous sporadic colonic adenomas were identified, and 60 eligible patients were randomized to placebo or active dietary intervention (ADI) twice a day, for 60 d before surveillance colonoscopy. ADI was a mixture of 175 mg milk thistle extract, 20 mg secoisolariciresinol and 750 mg oat fiber extract. ER-β and ER-α expression, apoptosis and proliferation (Ki-67 LI) were assessed in colon samples. RESULTS:No adverse event related to ADI was recorded. ADI administration showed a significant increases in ER-β protein (0.822 ± 0.08 vs 0.768 ± 0.10, P = 0.04) and a general trend to an increase in ER-β LI (39.222 ± 2.69vs 37.708 ± 5.31,P = 0.06), ER-β/ER-α LI ratio (6.564 ± 10.04 vs 2.437 ± 1.53, P = 0.06), terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (35.592 ± 14.97 vs 31.541 ± 11.54, P = 0.07) and Ki-67 (53.923 ± 20.91 vs 44.833 ± 10.38, P = 0.07) approximating statistical significance. A significant increase of ER-β protein (0.805 ± 0.13 vs 0.773 ± 0.13,P = 0.04), mRNA (2.278 ± 1.19vs 1.105 ± 1.07, P < 0.02) and LI (47.533 ± 15.47 vs 34.875 ± 16.67,P < 0.05) and a decrease of ER-α protein (0.423 ± 0.06vs 0.532 ± 0.11,P < 0.02) as well as a trend to increase of ER-β/ER-α protein in ADI vs placebo group were observed in patients without polyps (1.734 ± 0.20 vs 1.571 ± 0.42, P = 0.07). CONCLUSION:The role of ER-β on the control of apoptosis, and its amenability to dietary intervention, are supported in our study.展开更多
Phytoestrogens have multiple actions within target cells, including the epigenome, which could be beneficial to the development and progression of breast cancer. In this brief review the action of phytoestrogens on oe...Phytoestrogens have multiple actions within target cells, including the epigenome, which could be beneficial to the development and progression of breast cancer. In this brief review the action of phytoestrogens on oestrogen receptors, cell signalling pathways, regulation of the cell cycle, apoptosis, steroid synthesis and epigenetic events in relation to breast cancer are discussed. Phytoestrogens can bind weakly to oestrogen receptors(ERs) and some have a preferential affinity for ERβ which can inhibit the transcriptional growthpromoting activity of ERα. However only saturating doses of phytoestrogens, stimulating both ERα and β, exert growth inhibitory effects. Such effects on growth may be through phytoestrogens inhibiting cell signalling pathways. Phytoestrogens have also been shown to inhibit cyclin D1 expression but increase the expression of cyclin-dependent kinase inhibitors(p21 and p27) and the tumour suppressor gene p53. Again these effects are only observed at high(> 10) μmol/L doses of phytoestrogens. Finally the effects of phytoestrogens on breast cancer may be mediated by their ability toinhibit local oestrogen synthesis and induce epigenetic changes. There are, though, difficulties in reconciling epidemiological and experimental data due to the fact experimental doses, both in vivo and in vitro, far exceed the circulating concentrations of "free" unbound phytoestrogens measured in women on a high phytoestrogen diet or those taking phytoestrogen supplements.展开更多
Type 2 diabetes(T2D)has become a major public health threat across the globe.It has been widely acknowledged that diet plays an important role in the development and management of T2D.Phytoestrogens are polyphenols th...Type 2 diabetes(T2D)has become a major public health threat across the globe.It has been widely acknowledged that diet plays an important role in the development and management of T2D.Phytoestrogens are polyphenols that are structurally similar to endogenous estrogen and have weak estrogenic properties.Emerging evidence from pre-clinical models has suggested that phytoestrogens may have anti-diabetic function via both estrogendependent and estrogen-independent pathways.In the current review,we have summarized the evidence linking two major types of phytoestrogens,isoflavones and lignans,and T2D from epidemiological studies and clinical trials.The cross-sectional and prospective cohort studies have reported inconsistent results,which may due to the large variations in different populations and measurement errors in dietary intakes.Long-term intervention studies using isoflavone supplements have reported potential beneficial effects on glycemic parameters in postmenopausal women,while results from short-term smallsize clinical trials are conflicting.Taken together,the current evidence from different study designs is complex and inconsistent.Although the widespread use of phytoestrogens could not be recommended yet,habitual consumption of phytoestrogens,particularly their intact food sources like soy and whole flaxseed,could be considered as a component of overall healthy dietary pattern for prevention and management of T2D.展开更多
Sex hormone estrogen is one of the most active intrinsic angiogenesis regulators; its therapeutic use has been limited due to its carcinogenic potential. Plant-derived phytoestrogens are attractive alternatives, but r...Sex hormone estrogen is one of the most active intrinsic angiogenesis regulators; its therapeutic use has been limited due to its carcinogenic potential. Plant-derived phytoestrogens are attractive alternatives, but reports on their angiogenic activities often lack in-depth analysis and sometimes are controversial. Herein, we report a data-mining study with the existing literature, using IPA system to classify and characterize phytoestrogens based on their angiogenic properties and pharmacological consequences. We found that pro-angiogenic phytoestrogens functioned predominantly as cardiovascular protectors whereas anti-angiogenic phytoestrogens played a role in cancer prevention and therapy. This bidirectional regulation were shown to be target-selective and, for the most part, estrogen-receptor-dependent. The transactivation properties of ERα and ERβ by phytoestrogens were examined in the context of angiogenesis-related gene transcription. ERα and ERβ were shown to signal in opposite ways when complexed with the phytoestrogen for bidirectional regulation of angiogenesis. With ERα, phytoestrogen activated or inhibited transcription of some angiogenesis-related genes, resulting in the promotion of angiogenesis, whereas, with ERβ, phytoestrogen regulated transcription of angiogenesis-related genes, resulting in inhibition of angiogenesis. Therefore, the selectivity of phytoestrogen to ERα and ERβ may be critical in the balance of pro- or anti-angiogenesis process.展开更多
The androgen receptor(AR) signaling activated by dihydrotestosterone(DHT) plays critical roles in pros- tate cancer development and progression. Phytoestrogens, which are diphenolic compounds with estrogen and an-...The androgen receptor(AR) signaling activated by dihydrotestosterone(DHT) plays critical roles in pros- tate cancer development and progression. Phytoestrogens, which are diphenolic compounds with estrogen and an- ti-estrogen effects, can bind to estrogen receptors. However, their function on AR signaling has not been fully eluci- dated. In this study, dual-luciferase reporter assay, immunobloting, docking system test, MTT assay, immunofluores- cence and chromatin immunoprecipitation(ChlP) assays were employed to examine the potential effects of three phytoestrogens(genistein, daidzein, flavone) on DHT-activated prostate specific antigen(PSA) activation, cell proli- feration and AR transactivation in lymph node carcinoma of prostate(LNCaP) cells. Phytoestrogens were detected to down-regulate DHT-activated AR-mediated PSA promoter transactivation by dual-luciferase reporter system. Fur- thermore, three phytoestrogens, especially genistein, were demonstrated to significantly decrease AR-activated PSA protein expression by Western blotting analysis. MTT experiment proves that phytoestrogens, especially genistein, remarkably inhibits the DHT-indueed cell proliferation in LNCaP cells. To provide reasonable explanations for expe- rimental phenomena mentioned above, we did docking system test and detected phytoestrogens to share the same AR-binding site with DHT. To further prove the competition between phytoestrogen and DHT on AR binding, we examined the effects of phytoestrogens on DHT-activated AR nuclear translocation and immunofluorescence analysis which confirms that phytoestrogens, especially genistein, inhibit DHT-activated androgen receptor nuclear transloca- tion. Results from ChIP show that phytoestrogens down-regulate DHT-induces AR binding to the androgen response elements(AREs, including AREI, AREII, and AREIII) in PSA promoter. Genistein remarkably down-regulates AR, binding to the AREI located in -250---39 bp and AREIII in --4170---3978 bp in the presence of DHT. In general, three phytoestrogens were identified to inhibit DHT-AR binding by competitively binding to AR and inhibit AR-mediated transactivation. And genistein shows the strongest effects among three phytoestrogens. Our findings confirm that phytoestrogens are AR antagonist in the regulation of AR-related PSA activation and cell proliferation, which provides valuable insights into the treatment of prostate cancer.展开更多
In this study, we amplified aqnaporin I(AQP1) promoter sequence with polymerase chain reaction(PCR), then AQP1 promoter fragment and pGL2 basic vector were linked to create an artificial pGL2/AQP1 promoter re- por...In this study, we amplified aqnaporin I(AQP1) promoter sequence with polymerase chain reaction(PCR), then AQP1 promoter fragment and pGL2 basic vector were linked to create an artificial pGL2/AQP1 promoter re- porter system. A certain concentration of 17β-estradiol(E2) activated pGL2/AQPlp, which demonstrated the pGL2/AQPlp transcriptional system effective. The pGL2/AQP1 promoter reporter system was applied to evaluate the activate effect on AQP1 of different kinds of phytoestrogens. Dual hiciferase reporter gene activity assay showed that a certain concentration phytoestrogens including daidzein and genistein can increase AQP1 promoter transcription activity. In addition, E2, daidzein and genistein can make AQP1 protein endogenous expression level increase and promote the function of water scretion. The result can guide the clinical application to treat the Sjogren's syndrome and provide a necessary molecular tool for the subsequent drug screening.展开更多
Nano-targeted delivery systems have been widely used for breast tumor drug delivery.Estrogen receptors are considered to be significant drug delivery target receptors due to their overexpression in a variety of tumor ...Nano-targeted delivery systems have been widely used for breast tumor drug delivery.Estrogen receptors are considered to be significant drug delivery target receptors due to their overexpression in a variety of tumor cells.However,targeted ligands have a significant impact on the safety and effectiveness of active delivery systems,limiting the clinical transformation of nanoparticles.Phytoestrogens have shown good biosafety characteristics and some affinity with the estrogen receptor.In the present study,molecular docking was used to select tanshinone IIA(Tan IIA)among phytoestrogens as a target ligand to be used in nanodelivery systems with somemodifications.Modified Tan IIA(Tan-NH2)showed a good biosafety profile and demonstrated tumor-targeting,anti-tumor and anti-tumor metastasis effects.Moreover,the ligand was utilized with the anti-tumor drug Dox-loaded mesoporous silica nanoparticles via chemical modification to generate a nanocomposite Tan-Dox-MSN.Tan-Dox-MSN had a uniform particle size,good dispersibility and high drug loading capacity.Validation experiments in vivo and in vitro showed that it also had a better targeting ability,anti-tumor effect and lower toxicity in normal organs.These results supported the idea that phytoestrogens with high affinity for the estrogen receptor could improve the therapeutic efficacy of nano-targeted delivery systems in breast tumors.展开更多
Obesity is now present worldwide, including China, India and developing countries. It now seems no longer acceptable to argue that obesity can simply be explained in terms of caloric consumption only using simple conc...Obesity is now present worldwide, including China, India and developing countries. It now seems no longer acceptable to argue that obesity can simply be explained in terms of caloric consumption only using simple concept of energy in and energy out. There may be specific causes of altered metabolism that produce nutritional imbalances. Individual variation in response to food intake may also be considered. Specific substances in the food chain can influence meta-bolism towards an increase in fat deposits. Xenoestrogens have been suggested to have such an influence. Soy contains phytoestrogens plus phytates, protease inhibitors and other anti-nutrients which block or compromise the body’s uptake of essential vitamins and minerals. This may contribute to nutritional anomalies. We analyzed data from WHO and FAO for 167 countries. These contained percentage of obese individuals (BMI > 30 kg/m2), GDP, caloric consump-tion per capita, and sugar and soy consumption per capita. Regressions and partial correlations were used. Soy con-sumption correlates significantly with levels of obesity, irrespective of GDP and caloric intake. For instance, poor Latin America with soy consumption of 28.9 kg/person/year has more obesity (18.4%) than better off European Union (14.1%) consuming 16.1 kg/person/year of soy. Soy consumption seems to contribute approximately 10% - 21% to the worldwide variation in obesity, depending on the method of statistical analysis. The ubiquitous presence of unfermented soy products in mass produced foods seems to be an important contributor to the obesity epidemic.展开更多
Objective:To compare the cardioprotective efficacy of equimolar doses(50 mM/kg,p.o.)of phloretin and genistein against doxorubicin-induced cardiotoxicity in rats.Methods:Cardiotoxicity was induced in rats by intraperi...Objective:To compare the cardioprotective efficacy of equimolar doses(50 mM/kg,p.o.)of phloretin and genistein against doxorubicin-induced cardiotoxicity in rats.Methods:Cardiotoxicity was induced in rats by intraperitoneal injection of 6 mg/kg doxorubicin on alternative days till the cumulative dose reached 30 mg/kg.This study included four treatment groups of rats(n=6):the control group(0.5%carboxymethyl cellulose solution-treated),the doxorubicin-treated group(0.5%carboxymethyl cellulose solution along with doxorubicin),the genistein-treated group(50 mM/kg/day;p.o.along with doxorubicin)and phloretin-treated group(50 mM/kg/day;p.o.along with doxorubicin).On the 10th day of dosing,rats were anesthetized for recording ECG,mean arterial pressure,and left ventricular function.Oxidative stress,nitric oxide levels,and inflammatory cytokines were estimated in the cardiac tissue.Cardiac function parameters(creatine kinase MB,lactate dehydrogenase,aspartate aminotransferase,and alanine transaminase)were estimated in the serum samples.Results:Phloretin treatment inhibited doxorubicin-induced oxidative stress and also reduced nitric oxide levels in cardiac tissues of rats.Phloretin administration attenuated doxorubicin-induced alterations in hemodynamic parameters(heart rate,mean arterial blood pressure,and left ventricular function)and suppressed the expression of pro-inflammatory cytokines.The cardiac injury markers like creatine kinase MB,lactate dehydrogenase,aspartate aminotransferase,and alanine transaminase were reduced by both genistein and phloretin.All these effects of phloretin were more prominent than genistein.Conclusions:Phloretin offers cardioprotection that is comparable to genistein,a clinically validated cardioprotectant against doxorubicin-induced cardiotoxicity.Further studies are needed to confirm and establish the therapeutic utility of phloretin as a chemopreventive adjuvant to doxorubicin chemotherapy.展开更多
This study was aimed to determine whether flaxseed lignans could affect the growth of skeletal muscle in male animals and its possible mechanisms. The impact of flaxseed lignans on the skeletal muscle in male rats was...This study was aimed to determine whether flaxseed lignans could affect the growth of skeletal muscle in male animals and its possible mechanisms. The impact of flaxseed lignans on the skeletal muscle in male rats was determined in vivo. Flaxseed lignans (50 ppm) and daidzein (5 ppm) were added into the basal diets, respectively. The concentrations of serum lignans and daidzein were measured by high performance liquid chromatography (HPLC), and the serum growth hormone and testosterone (T) levels were analyzed by radioimmunoassay (RIA), and the expression of estrogen receptor β (ER β) in the soleus muscle and hypothalamus were determined by reverse-transcription polymerase chain reaction (RT-PCR). Flaxseed lignans and daidzein could significantly improve the feed efficiency and facilitate the weight gain of the femoral muscle in male rats. The ratio of RNA to DNA in the muscles and serum T levels was remarkably increased, whereas, the urea nitrogen concentrations were significantly decreased by flaxseed lignan and/or its metabolites and daidzein. Meanwhile, the expression of ER β in soleus muscle and hypothalamus were both upgraded by the two phytoestrogens. Flaxseed lignan promoted the growth of male rats, and it might be by regulating serum T levels by binding to ER β in the hypothalamus. In turn, it depressed the catabolism of protein and promoted the hypertrophy of skeletal muscle ceils.展开更多
Breast cancer is a frightful disease and serious concern in women around the world causing significant health care burden in both developed and developing countries. Extensive research work has shown that breast cance...Breast cancer is a frightful disease and serious concern in women around the world causing significant health care burden in both developed and developing countries. Extensive research work has shown that breast cancer provides strong resistance to chemical agents, U V radiation,and hormonal treatments. It is generally accepted that cell genetics is not the only main reason for breast cancer and genetic risk factors, for example, mutations in RRCAI and BRCA2 genes constitute 5%-10% of all breast cancer rates. Other related factors include age, gender,race, ethnicity, weight, reproductive factors, exo-and endogenous hormonal exposures, oral contraceptives use, ultraviolet radiation, diet, and night work(circadian disruption). Many studies have revealed that dietary isoflavones regulate breast cancer occurrence, recurrence and prognosis. Dietary isoflavones have long been part of Asian population diet and there is a significant increase as compared to dietary isoflavones intake among other populations. Dietary isoflavones are natural phytoestrogens having both estrogenic and anti-estrogenic potentials on breast cancer cells in culture, animal models and in experimental trials. This literature survey provides a comprehensive overview on the tumor preventive and tumor promoting potentials of dietary isoflavones on breast cancer. In addition, this paper provides a literature review of dietary isoflavones and their effects on up-regulation and down-regulation of different signaling pathways, genes and proteins. Finally, future perspectives of dietary isoflavones and breast cancer researchers are also critically discussed, which will provide a deeper insight regarding the inner molecular mechanisms of action.展开更多
Soybeans have been shown to contain larger concentrations of isoflavones than other plant foods. The colonic micro-floras of some individuals metabolize isoflavones, including the soy phytoestrogen daidzein, to compou...Soybeans have been shown to contain larger concentrations of isoflavones than other plant foods. The colonic micro-floras of some individuals metabolize isoflavones, including the soy phytoestrogen daidzein, to compounds with altered estrogenic activity that may affect health. Monkeys have been used as models to predict the effect of colonic microorganisms on the metabolism of phytoestrogens. We studied the effect of consumption of a diet rich in soy protein on the metabolism of added daidzein by the intestinal microfloras of monkeys. The metabolism of daidzein by cultures of the colonic microfloras from eight males and eight females of Macaca fascicularis, 6 - 12 years old, consuming diets containing either soy or casein, and two males and three females of Macaca nemestrina, 3 - 5 months old, consuming infant formula, was investigated using high-performance liquid chromatographic analyses. Cultures from ten of the 16 adult monkeys and all five infant monkeys metabolized the added daidzein within 24 h. Daidzein was metabolized within 48 h by cultures from five other monkeys, but it remained even after 72 h in a culture from one female monkey on a casein diet. Equol and dihydrodaidzein were the only metabolites found. Individual variation among monkeys in the efficiency of daidzein metabolism was observed, but there appeared to be no correlation between diet and daidzein metabolism by the intestinal microflora. The intestinal microfloras of most monkeys tested were efficient in the biotransformation of daidzein to equol, regardless of the animals’ consumption of soy protein. Differences in the metabolism of isoflavones by the colonic microfloras of humans and experimental animals should be considered when extrapolating results from animals to humans.展开更多
Menopause is the last step in the reproductive history of a woman. The ovaries stop producing hormones and the body reacts by lowering its functions, including the cognitive one. Phytoestrogens are plant products with...Menopause is the last step in the reproductive history of a woman. The ovaries stop producing hormones and the body reacts by lowering its functions, including the cognitive one. Phytoestrogens are plant products with the estrogen-like activity which are able to mimic many of estrogen’s functions. The aim of the present experiment was to study the effects of 30 days of regular consumption of soy-enriched bread containing a known amount of phytoestrogens (genistein and daidzein) in climacteric or menopausal women. Thirty women at different stages of menopause (climacteric, within 5 years of menopause, more than 5 years of menopause) were asked to include 200 g/die of bread containing 40 mg of phytoestrogens in their diet. The effect of the regular consumption of this bread on common menopausal symptoms and cognitive parameters was determined before and after 30 days through questionnaires and experimental tests. Phytoestrogens were measured in the urine. Twenty-five women completed the study. Independence of the menopause stage, there was a significant increase of phytoestrogens in the urine and a decrease of the classical symptoms (i.e., hot flushes). Moreover, the women showed a significant improvement in attentional performance tests, the quality of life index and pain intensity. Phytoestrogens would be an important supplement in aging women due to their ability to induce estrogen-like effects without the potential side effects of estrogens. Their presence in soy-enriched bread, a food commonly present in meals, avoids consideration of their consumption as a drug.展开更多
To investigate the preventive effect of epimedium-derived phytoestrogen (PE) on osteoporosis induced by ovariectomy (OVX) in rats, 11-month-old female Wistar rats were randomly divided into Sham, OVX and PE groups...To investigate the preventive effect of epimedium-derived phytoestrogen (PE) on osteoporosis induced by ovariectomy (OVX) in rats, 11-month-old female Wistar rats were randomly divided into Sham, OVX and PE groups. One week after OVX, daily oral administration of PE (0.4 g·kg^-1·day^-1) started in PE group, and rats in Sham and OVX groups were given vehicle accordingly. The administrations lasted for 12 weeks. The biological markers including serum osteocalcin (OC) and urinary deoxypyridinoline (DPD) for bone tumover were evaluated at the end of the 12th week. On the 13th week, all the rats were sacrificed. The right proximal tibiae were removed, subjected to micro CT for determination of trabecular bone structure and then bone histomorphometry was performed to assess bone remodeling. The OVX rats were in a high bone tumover status as evidenced by increased bone formation markers and bone resorption markers. Treatment with PE could suppress the high bone turnover rate in OVX rats. Micro CT data revealed that PE treatment could ameliorate the deterioration of the micro-architecture of proximal tibiae induced by OVX, as demonstrated by greater bone volume, increased trabecular thickness and less trabecular separation in PE group in comparison with OVX group. The static and dynamic parameters of bone histomorphometry indicated that there were significant increases in bone formation variables and significant decreases in bone resorption variables between PE and OVX groups. The findings suggest that PE has a beneficial effect on trabecular bone in OVX rat model and this effect is possibly associated with stimulation of bone formation as well as inhibition of bone resorption.展开更多
Oestrogens are not exclusive to the female gender but occur in moderate circulating levels of 25-70 pg ml^-1 in men, compared to 44- 153 pg ml^-1 in women. Arising from aromatisation of testosterone (T), oestrogen i...Oestrogens are not exclusive to the female gender but occur in moderate circulating levels of 25-70 pg ml^-1 in men, compared to 44- 153 pg ml^-1 in women. Arising from aromatisation of testosterone (T), oestrogen is considered to have many opposing physiological functions and the progressive T decline in the aging male is associated with relative and/or absolute increase in serum oestradiol (E2). Sexual disinterest and erectile dysfunction (ED) in the elderly may well be due to pathophysiological E2-T imbalance; the altered hormonal ratio may also explain the higher incidence of ED in hyperestrogenism or following exposure to environmental/plant oestrogens.展开更多
Objective To evaluate the influence of an extract of Genista tinctoria L. herba (GT) or methylparaben (MP) on histopathological changes and 2 biomarkers of oxidative stress in rats subchronicly exposed to bispheno...Objective To evaluate the influence of an extract of Genista tinctoria L. herba (GT) or methylparaben (MP) on histopathological changes and 2 biomarkers of oxidative stress in rats subchronicly exposed to bisphenol A (BPA). Methods Adult female Wistar rats were orally exposed for 90 d to BPA (50 mg/kg), BPA+GT (35 mg isoflavones/kg) or BPA+MP (250 mg/kg). Plasma and tissue samples were taken from liver, kidney, thyroid, uterus, ovary, and mammary gland after 30, 60, and 90 d of exposure respectively. Lipid peroxidation and in vivo hydroxyl radical production were evaluated by histological analysis along with malondialdehyde and 2,3-dihydroxybenzoic acid detection. Results The severity of histopathological changes in liver and kidneys was lower after GT treatment than after BPA or BPA+MP treatment. A minimal thyroid receptor antagonist effect was only observed after BPA+MP treatment. The abnormal folliculogenesis increased in a time-dependent manner, and the number of corpus luteum decreased. No significant histological alterations were found in the uterus. The mammary gland displayed specific estrogen stimulation changes at all periods. Both MP and GT revealed antioxidant properties reducing lipid peroxidation and BPA-induced hydroxyl radical generation. Conclusion GT L. extract ameliorates the toxic effects of BPA and is proved to have antioxidant potential and antitoxic effect. MP has antioxidant properties, but has either no effect or exacerbates the BPA-induced histopathological changes.展开更多
Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for...Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for this protection. Methods Human aortic endothelial cells subjected to normal (5mmol/L) or high glucose (25mmol/L) were treated with genistein at 0, 50, 100nmol/L. Parallel experiments were performed with 100nM 17b-estradiol, and also in the presence and absence of the pure anti-estrogen ICI-182,780 (100nmol/L). The effects on cell apoptotic DNA fragmentation were determined using cell death ELISA, and the effects on cellular proliferation were determined using tritiated thymidine incorporation assay. Estrogen receptor expression was detected by Taqman quantitative PCR. Results Genistein at 100nmol/L significantly reduced high glucose-induced DNA fragmentation, and reversed cell DNA synthesis inhibition (P <0.001) after 24 hours' incubation. The effect of genistein was completely blocked by ICI-182,780 administration. Estrogen receptor beta, but not alpha was found to be expressed in these cells. Conclusion Isoflavone genistein shows protection against high glucose-induced cell damage through estrogen receptor beta, reducing apoptotic DNA damage and protecting from the inhibition of cell proliferation.展开更多
Objective:To investigate the estrogenic effect of(8,9)-furanyl-pterocarpan-3-ol(FPC)on growth of human breast cancer T47D cells and the interactions between the FPC and tamoxifen(TAM),on the growth of estrogen recepto...Objective:To investigate the estrogenic effect of(8,9)-furanyl-pterocarpan-3-ol(FPC)on growth of human breast cancer T47D cells and the interactions between the FPC and tamoxifen(TAM),on the growth of estrogen receptor-dependent breast cancer T47D cells.Methods:The proliferation effect of FPC were conducted on T47D cells in vitro by MTT test.T47D cells were treated with FPC alone(0.01-200μmol/L)or in combination with TAM 20 nmol/L.Furthermore,the expression of ERαor c-Myc were also determined by immunohistochemistry.Results:The results indicated that administration of an anti-estrogen TAM showed growth inhibitory effect on T47D cells,wheraes co-administered with low concentration(less than 1μmol/L)of FPC attenuated to promote cell proliferation.In contrast,the combination of TAM with higher doses(more than 20μmol/L)of FPC showed growth inhibitory.This result was supported by immunocytochemistry studies that the administration of 20 nmol/L TAM down-regulated ER-αand c-Myc,but the combination of 20 nmol/L TAM and 1μmol/L FPC robustly up-regulated expression of ER-α.Thus,the reduced growth inhibition of TAM 20 nmol/L by FPC 1μmol/L on T47D cells may act via the modulation of ER-α.Conclusions:The findings indicate and suggest that FPC had estrogenic activity at low concentrations and anti-estrogenic effect that are likely to be regulated by c-Myc and estrogen receptors.We also confirm that low concentration of FPC attenuated the growth-inhibitory effects of TAM on mammary tumor prevention.Therefore,the present study suggests that caution is warranted regarding the consumption of dietary FPC by breast cancer patients while on TMA therapy.展开更多
Objective:To investigate the bone-resorbing effect of demethylbelamcandaquinone B(Dmcq B)extracted from Marantodes pumilum var.alata on osteoclast differentiation in RAW264.7 cells.Methods:RAW264.7 macrophages were di...Objective:To investigate the bone-resorbing effect of demethylbelamcandaquinone B(Dmcq B)extracted from Marantodes pumilum var.alata on osteoclast differentiation in RAW264.7 cells.Methods:RAW264.7 macrophages were differentiated using RANKL into osteoclast-like cells.Then,they were treated with 10μg/mL Marantodes pumilum var.alata crude aqueous extract,5μg/mL dichloromethane fraction,and 0.6μg/mL Dmcq B and 0.06μg/mL estradiol.Tartrate-resistant acid phosphatase 5b(TRACP 5b)as an osteoclast phenotypic marker was determined by TRACP staining and TRACP 5b colometric assay,and bone-resorbing pits were examined.The gene expression of pro-inflammatory cytokines(TNF-αand IL-6)was measured.Moreover,the protein expressions of pro-inflammatory cytokines(TNF-αand IL-6)and estrogen receptors were evaluated.Results:Marantodes pumilum var.alata crude aqueous extract and Dmcq B inhibited RANKL-stimulated osteoclast differentiation as evidenced by size reduction of giant multinucleated osteoclast cells,decreased TRACP 5b activity as well as the subsiding of resorbed pit area compared with normal control.In addition,they reduced the gene and protein expressions of TNF-αand IL-6.Marantodes pumilum var.alata,Dmcq B,and estradiol treatments increased the protein expressions of estrogen receptors alpha and beta in osteoclasts.Conclusions:Marantodes pumilum var.alata and its active compound,Dmcq B can inhibit osteoclast differentiation.展开更多
MRI provides a highly sensitive technique for early detection of abnormal breast tissue. It is useful for identifying a status of proliferation, angiogenesis, and microvascular permeability, which may indicate early b...MRI provides a highly sensitive technique for early detection of abnormal breast tissue. It is useful for identifying a status of proliferation, angiogenesis, and microvascular permeability, which may indicate early breast neoplasm formation. We retrospectively studied 2005 breast MRI images from Taiwan Residents women and classified them as either healthy or unhealthy according to BI-RADS categories. A subgroup of our study patients had received estrogen supplements, containing estrogen components or phytoestrogen, for at least 3 months. These patients’ images were also classified into the healthy and unhealthy groups. These two groups were compared and a significant difference was found between them (P < 0.002). Comparison of the MRI images also identified certain cases that demonstrated a typical estrogen/phytoestrogen effect or a withdrawal effect. The overuse of estrogen or phytoestrogen supplements can increase breast glandular tissue proliferation, as reflected on MRI images. Such proliferation may increase the patient’s risk of future breast cancer.展开更多
基金Supported by Wholly granted from R and D, CMD Pharma Limited, United Kingdom
文摘AIM:To assess the safety and effect of the supplementation of a patented blend of dietary phytoestrogens and insoluble fibers on estrogen receptor (ER)-β and biological parameters in sporadic colonic adenomas. METHODS:A randomized, double-blind placebo-controlled trial was performed. Patients scheduled to undergo surveillance colonoscopy for previous sporadic colonic adenomas were identified, and 60 eligible patients were randomized to placebo or active dietary intervention (ADI) twice a day, for 60 d before surveillance colonoscopy. ADI was a mixture of 175 mg milk thistle extract, 20 mg secoisolariciresinol and 750 mg oat fiber extract. ER-β and ER-α expression, apoptosis and proliferation (Ki-67 LI) were assessed in colon samples. RESULTS:No adverse event related to ADI was recorded. ADI administration showed a significant increases in ER-β protein (0.822 ± 0.08 vs 0.768 ± 0.10, P = 0.04) and a general trend to an increase in ER-β LI (39.222 ± 2.69vs 37.708 ± 5.31,P = 0.06), ER-β/ER-α LI ratio (6.564 ± 10.04 vs 2.437 ± 1.53, P = 0.06), terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (35.592 ± 14.97 vs 31.541 ± 11.54, P = 0.07) and Ki-67 (53.923 ± 20.91 vs 44.833 ± 10.38, P = 0.07) approximating statistical significance. A significant increase of ER-β protein (0.805 ± 0.13 vs 0.773 ± 0.13,P = 0.04), mRNA (2.278 ± 1.19vs 1.105 ± 1.07, P < 0.02) and LI (47.533 ± 15.47 vs 34.875 ± 16.67,P < 0.05) and a decrease of ER-α protein (0.423 ± 0.06vs 0.532 ± 0.11,P < 0.02) as well as a trend to increase of ER-β/ER-α protein in ADI vs placebo group were observed in patients without polyps (1.734 ± 0.20 vs 1.571 ± 0.42, P = 0.07). CONCLUSION:The role of ER-β on the control of apoptosis, and its amenability to dietary intervention, are supported in our study.
文摘Phytoestrogens have multiple actions within target cells, including the epigenome, which could be beneficial to the development and progression of breast cancer. In this brief review the action of phytoestrogens on oestrogen receptors, cell signalling pathways, regulation of the cell cycle, apoptosis, steroid synthesis and epigenetic events in relation to breast cancer are discussed. Phytoestrogens can bind weakly to oestrogen receptors(ERs) and some have a preferential affinity for ERβ which can inhibit the transcriptional growthpromoting activity of ERα. However only saturating doses of phytoestrogens, stimulating both ERα and β, exert growth inhibitory effects. Such effects on growth may be through phytoestrogens inhibiting cell signalling pathways. Phytoestrogens have also been shown to inhibit cyclin D1 expression but increase the expression of cyclin-dependent kinase inhibitors(p21 and p27) and the tumour suppressor gene p53. Again these effects are only observed at high(> 10) μmol/L doses of phytoestrogens. Finally the effects of phytoestrogens on breast cancer may be mediated by their ability toinhibit local oestrogen synthesis and induce epigenetic changes. There are, though, difficulties in reconciling epidemiological and experimental data due to the fact experimental doses, both in vivo and in vitro, far exceed the circulating concentrations of "free" unbound phytoestrogens measured in women on a high phytoestrogen diet or those taking phytoestrogen supplements.
文摘Type 2 diabetes(T2D)has become a major public health threat across the globe.It has been widely acknowledged that diet plays an important role in the development and management of T2D.Phytoestrogens are polyphenols that are structurally similar to endogenous estrogen and have weak estrogenic properties.Emerging evidence from pre-clinical models has suggested that phytoestrogens may have anti-diabetic function via both estrogendependent and estrogen-independent pathways.In the current review,we have summarized the evidence linking two major types of phytoestrogens,isoflavones and lignans,and T2D from epidemiological studies and clinical trials.The cross-sectional and prospective cohort studies have reported inconsistent results,which may due to the large variations in different populations and measurement errors in dietary intakes.Long-term intervention studies using isoflavone supplements have reported potential beneficial effects on glycemic parameters in postmenopausal women,while results from short-term smallsize clinical trials are conflicting.Taken together,the current evidence from different study designs is complex and inconsistent.Although the widespread use of phytoestrogens could not be recommended yet,habitual consumption of phytoestrogens,particularly their intact food sources like soy and whole flaxseed,could be considered as a component of overall healthy dietary pattern for prevention and management of T2D.
基金supported by National Natural Science Foundation of China(No.81274128)China National Funds for Distinguished Young Scientists(No.81125024)the Program of the State Key Development Program for Basic Research of China(No.2012CB723504)
文摘Sex hormone estrogen is one of the most active intrinsic angiogenesis regulators; its therapeutic use has been limited due to its carcinogenic potential. Plant-derived phytoestrogens are attractive alternatives, but reports on their angiogenic activities often lack in-depth analysis and sometimes are controversial. Herein, we report a data-mining study with the existing literature, using IPA system to classify and characterize phytoestrogens based on their angiogenic properties and pharmacological consequences. We found that pro-angiogenic phytoestrogens functioned predominantly as cardiovascular protectors whereas anti-angiogenic phytoestrogens played a role in cancer prevention and therapy. This bidirectional regulation were shown to be target-selective and, for the most part, estrogen-receptor-dependent. The transactivation properties of ERα and ERβ by phytoestrogens were examined in the context of angiogenesis-related gene transcription. ERα and ERβ were shown to signal in opposite ways when complexed with the phytoestrogen for bidirectional regulation of angiogenesis. With ERα, phytoestrogen activated or inhibited transcription of some angiogenesis-related genes, resulting in the promotion of angiogenesis, whereas, with ERβ, phytoestrogen regulated transcription of angiogenesis-related genes, resulting in inhibition of angiogenesis. Therefore, the selectivity of phytoestrogen to ERα and ERβ may be critical in the balance of pro- or anti-angiogenesis process.
文摘The androgen receptor(AR) signaling activated by dihydrotestosterone(DHT) plays critical roles in pros- tate cancer development and progression. Phytoestrogens, which are diphenolic compounds with estrogen and an- ti-estrogen effects, can bind to estrogen receptors. However, their function on AR signaling has not been fully eluci- dated. In this study, dual-luciferase reporter assay, immunobloting, docking system test, MTT assay, immunofluores- cence and chromatin immunoprecipitation(ChlP) assays were employed to examine the potential effects of three phytoestrogens(genistein, daidzein, flavone) on DHT-activated prostate specific antigen(PSA) activation, cell proli- feration and AR transactivation in lymph node carcinoma of prostate(LNCaP) cells. Phytoestrogens were detected to down-regulate DHT-activated AR-mediated PSA promoter transactivation by dual-luciferase reporter system. Fur- thermore, three phytoestrogens, especially genistein, were demonstrated to significantly decrease AR-activated PSA protein expression by Western blotting analysis. MTT experiment proves that phytoestrogens, especially genistein, remarkably inhibits the DHT-indueed cell proliferation in LNCaP cells. To provide reasonable explanations for expe- rimental phenomena mentioned above, we did docking system test and detected phytoestrogens to share the same AR-binding site with DHT. To further prove the competition between phytoestrogen and DHT on AR binding, we examined the effects of phytoestrogens on DHT-activated AR nuclear translocation and immunofluorescence analysis which confirms that phytoestrogens, especially genistein, inhibit DHT-activated androgen receptor nuclear transloca- tion. Results from ChIP show that phytoestrogens down-regulate DHT-induces AR binding to the androgen response elements(AREs, including AREI, AREII, and AREIII) in PSA promoter. Genistein remarkably down-regulates AR, binding to the AREI located in -250---39 bp and AREIII in --4170---3978 bp in the presence of DHT. In general, three phytoestrogens were identified to inhibit DHT-AR binding by competitively binding to AR and inhibit AR-mediated transactivation. And genistein shows the strongest effects among three phytoestrogens. Our findings confirm that phytoestrogens are AR antagonist in the regulation of AR-related PSA activation and cell proliferation, which provides valuable insights into the treatment of prostate cancer.
文摘In this study, we amplified aqnaporin I(AQP1) promoter sequence with polymerase chain reaction(PCR), then AQP1 promoter fragment and pGL2 basic vector were linked to create an artificial pGL2/AQP1 promoter re- porter system. A certain concentration of 17β-estradiol(E2) activated pGL2/AQPlp, which demonstrated the pGL2/AQPlp transcriptional system effective. The pGL2/AQP1 promoter reporter system was applied to evaluate the activate effect on AQP1 of different kinds of phytoestrogens. Dual hiciferase reporter gene activity assay showed that a certain concentration phytoestrogens including daidzein and genistein can increase AQP1 promoter transcription activity. In addition, E2, daidzein and genistein can make AQP1 protein endogenous expression level increase and promote the function of water scretion. The result can guide the clinical application to treat the Sjogren's syndrome and provide a necessary molecular tool for the subsequent drug screening.
基金supported by the Tianjin University of Traditional Chinese Medicine Scientific Research Project for the NewTeacher[grant number:XJS2022212]The Science and Technology Program of Tianjin[grant number:21YJDJC00020]The Science and Technology Project of Haihe Laboratory of Modern Chinese Medicine[grant number:22HHZYSS00005].
文摘Nano-targeted delivery systems have been widely used for breast tumor drug delivery.Estrogen receptors are considered to be significant drug delivery target receptors due to their overexpression in a variety of tumor cells.However,targeted ligands have a significant impact on the safety and effectiveness of active delivery systems,limiting the clinical transformation of nanoparticles.Phytoestrogens have shown good biosafety characteristics and some affinity with the estrogen receptor.In the present study,molecular docking was used to select tanshinone IIA(Tan IIA)among phytoestrogens as a target ligand to be used in nanodelivery systems with somemodifications.Modified Tan IIA(Tan-NH2)showed a good biosafety profile and demonstrated tumor-targeting,anti-tumor and anti-tumor metastasis effects.Moreover,the ligand was utilized with the anti-tumor drug Dox-loaded mesoporous silica nanoparticles via chemical modification to generate a nanocomposite Tan-Dox-MSN.Tan-Dox-MSN had a uniform particle size,good dispersibility and high drug loading capacity.Validation experiments in vivo and in vitro showed that it also had a better targeting ability,anti-tumor effect and lower toxicity in normal organs.These results supported the idea that phytoestrogens with high affinity for the estrogen receptor could improve the therapeutic efficacy of nano-targeted delivery systems in breast tumors.
文摘Obesity is now present worldwide, including China, India and developing countries. It now seems no longer acceptable to argue that obesity can simply be explained in terms of caloric consumption only using simple concept of energy in and energy out. There may be specific causes of altered metabolism that produce nutritional imbalances. Individual variation in response to food intake may also be considered. Specific substances in the food chain can influence meta-bolism towards an increase in fat deposits. Xenoestrogens have been suggested to have such an influence. Soy contains phytoestrogens plus phytates, protease inhibitors and other anti-nutrients which block or compromise the body’s uptake of essential vitamins and minerals. This may contribute to nutritional anomalies. We analyzed data from WHO and FAO for 167 countries. These contained percentage of obese individuals (BMI > 30 kg/m2), GDP, caloric consump-tion per capita, and sugar and soy consumption per capita. Regressions and partial correlations were used. Soy con-sumption correlates significantly with levels of obesity, irrespective of GDP and caloric intake. For instance, poor Latin America with soy consumption of 28.9 kg/person/year has more obesity (18.4%) than better off European Union (14.1%) consuming 16.1 kg/person/year of soy. Soy consumption seems to contribute approximately 10% - 21% to the worldwide variation in obesity, depending on the method of statistical analysis. The ubiquitous presence of unfermented soy products in mass produced foods seems to be an important contributor to the obesity epidemic.
文摘Objective:To compare the cardioprotective efficacy of equimolar doses(50 mM/kg,p.o.)of phloretin and genistein against doxorubicin-induced cardiotoxicity in rats.Methods:Cardiotoxicity was induced in rats by intraperitoneal injection of 6 mg/kg doxorubicin on alternative days till the cumulative dose reached 30 mg/kg.This study included four treatment groups of rats(n=6):the control group(0.5%carboxymethyl cellulose solution-treated),the doxorubicin-treated group(0.5%carboxymethyl cellulose solution along with doxorubicin),the genistein-treated group(50 mM/kg/day;p.o.along with doxorubicin)and phloretin-treated group(50 mM/kg/day;p.o.along with doxorubicin).On the 10th day of dosing,rats were anesthetized for recording ECG,mean arterial pressure,and left ventricular function.Oxidative stress,nitric oxide levels,and inflammatory cytokines were estimated in the cardiac tissue.Cardiac function parameters(creatine kinase MB,lactate dehydrogenase,aspartate aminotransferase,and alanine transaminase)were estimated in the serum samples.Results:Phloretin treatment inhibited doxorubicin-induced oxidative stress and also reduced nitric oxide levels in cardiac tissues of rats.Phloretin administration attenuated doxorubicin-induced alterations in hemodynamic parameters(heart rate,mean arterial blood pressure,and left ventricular function)and suppressed the expression of pro-inflammatory cytokines.The cardiac injury markers like creatine kinase MB,lactate dehydrogenase,aspartate aminotransferase,and alanine transaminase were reduced by both genistein and phloretin.All these effects of phloretin were more prominent than genistein.Conclusions:Phloretin offers cardioprotection that is comparable to genistein,a clinically validated cardioprotectant against doxorubicin-induced cardiotoxicity.Further studies are needed to confirm and establish the therapeutic utility of phloretin as a chemopreventive adjuvant to doxorubicin chemotherapy.
基金supported by the National Natural Science Foundation of China (39970534)
文摘This study was aimed to determine whether flaxseed lignans could affect the growth of skeletal muscle in male animals and its possible mechanisms. The impact of flaxseed lignans on the skeletal muscle in male rats was determined in vivo. Flaxseed lignans (50 ppm) and daidzein (5 ppm) were added into the basal diets, respectively. The concentrations of serum lignans and daidzein were measured by high performance liquid chromatography (HPLC), and the serum growth hormone and testosterone (T) levels were analyzed by radioimmunoassay (RIA), and the expression of estrogen receptor β (ER β) in the soleus muscle and hypothalamus were determined by reverse-transcription polymerase chain reaction (RT-PCR). Flaxseed lignans and daidzein could significantly improve the feed efficiency and facilitate the weight gain of the femoral muscle in male rats. The ratio of RNA to DNA in the muscles and serum T levels was remarkably increased, whereas, the urea nitrogen concentrations were significantly decreased by flaxseed lignan and/or its metabolites and daidzein. Meanwhile, the expression of ER β in soleus muscle and hypothalamus were both upgraded by the two phytoestrogens. Flaxseed lignan promoted the growth of male rats, and it might be by regulating serum T levels by binding to ER β in the hypothalamus. In turn, it depressed the catabolism of protein and promoted the hypertrophy of skeletal muscle ceils.
文摘Breast cancer is a frightful disease and serious concern in women around the world causing significant health care burden in both developed and developing countries. Extensive research work has shown that breast cancer provides strong resistance to chemical agents, U V radiation,and hormonal treatments. It is generally accepted that cell genetics is not the only main reason for breast cancer and genetic risk factors, for example, mutations in RRCAI and BRCA2 genes constitute 5%-10% of all breast cancer rates. Other related factors include age, gender,race, ethnicity, weight, reproductive factors, exo-and endogenous hormonal exposures, oral contraceptives use, ultraviolet radiation, diet, and night work(circadian disruption). Many studies have revealed that dietary isoflavones regulate breast cancer occurrence, recurrence and prognosis. Dietary isoflavones have long been part of Asian population diet and there is a significant increase as compared to dietary isoflavones intake among other populations. Dietary isoflavones are natural phytoestrogens having both estrogenic and anti-estrogenic potentials on breast cancer cells in culture, animal models and in experimental trials. This literature survey provides a comprehensive overview on the tumor preventive and tumor promoting potentials of dietary isoflavones on breast cancer. In addition, this paper provides a literature review of dietary isoflavones and their effects on up-regulation and down-regulation of different signaling pathways, genes and proteins. Finally, future perspectives of dietary isoflavones and breast cancer researchers are also critically discussed, which will provide a deeper insight regarding the inner molecular mechanisms of action.
文摘Soybeans have been shown to contain larger concentrations of isoflavones than other plant foods. The colonic micro-floras of some individuals metabolize isoflavones, including the soy phytoestrogen daidzein, to compounds with altered estrogenic activity that may affect health. Monkeys have been used as models to predict the effect of colonic microorganisms on the metabolism of phytoestrogens. We studied the effect of consumption of a diet rich in soy protein on the metabolism of added daidzein by the intestinal microfloras of monkeys. The metabolism of daidzein by cultures of the colonic microfloras from eight males and eight females of Macaca fascicularis, 6 - 12 years old, consuming diets containing either soy or casein, and two males and three females of Macaca nemestrina, 3 - 5 months old, consuming infant formula, was investigated using high-performance liquid chromatographic analyses. Cultures from ten of the 16 adult monkeys and all five infant monkeys metabolized the added daidzein within 24 h. Daidzein was metabolized within 48 h by cultures from five other monkeys, but it remained even after 72 h in a culture from one female monkey on a casein diet. Equol and dihydrodaidzein were the only metabolites found. Individual variation among monkeys in the efficiency of daidzein metabolism was observed, but there appeared to be no correlation between diet and daidzein metabolism by the intestinal microflora. The intestinal microfloras of most monkeys tested were efficient in the biotransformation of daidzein to equol, regardless of the animals’ consumption of soy protein. Differences in the metabolism of isoflavones by the colonic microfloras of humans and experimental animals should be considered when extrapolating results from animals to humans.
文摘Menopause is the last step in the reproductive history of a woman. The ovaries stop producing hormones and the body reacts by lowering its functions, including the cognitive one. Phytoestrogens are plant products with the estrogen-like activity which are able to mimic many of estrogen’s functions. The aim of the present experiment was to study the effects of 30 days of regular consumption of soy-enriched bread containing a known amount of phytoestrogens (genistein and daidzein) in climacteric or menopausal women. Thirty women at different stages of menopause (climacteric, within 5 years of menopause, more than 5 years of menopause) were asked to include 200 g/die of bread containing 40 mg of phytoestrogens in their diet. The effect of the regular consumption of this bread on common menopausal symptoms and cognitive parameters was determined before and after 30 days through questionnaires and experimental tests. Phytoestrogens were measured in the urine. Twenty-five women completed the study. Independence of the menopause stage, there was a significant increase of phytoestrogens in the urine and a decrease of the classical symptoms (i.e., hot flushes). Moreover, the women showed a significant improvement in attentional performance tests, the quality of life index and pain intensity. Phytoestrogens would be an important supplement in aging women due to their ability to induce estrogen-like effects without the potential side effects of estrogens. Their presence in soy-enriched bread, a food commonly present in meals, avoids consideration of their consumption as a drug.
文摘To investigate the preventive effect of epimedium-derived phytoestrogen (PE) on osteoporosis induced by ovariectomy (OVX) in rats, 11-month-old female Wistar rats were randomly divided into Sham, OVX and PE groups. One week after OVX, daily oral administration of PE (0.4 g·kg^-1·day^-1) started in PE group, and rats in Sham and OVX groups were given vehicle accordingly. The administrations lasted for 12 weeks. The biological markers including serum osteocalcin (OC) and urinary deoxypyridinoline (DPD) for bone tumover were evaluated at the end of the 12th week. On the 13th week, all the rats were sacrificed. The right proximal tibiae were removed, subjected to micro CT for determination of trabecular bone structure and then bone histomorphometry was performed to assess bone remodeling. The OVX rats were in a high bone tumover status as evidenced by increased bone formation markers and bone resorption markers. Treatment with PE could suppress the high bone turnover rate in OVX rats. Micro CT data revealed that PE treatment could ameliorate the deterioration of the micro-architecture of proximal tibiae induced by OVX, as demonstrated by greater bone volume, increased trabecular thickness and less trabecular separation in PE group in comparison with OVX group. The static and dynamic parameters of bone histomorphometry indicated that there were significant increases in bone formation variables and significant decreases in bone resorption variables between PE and OVX groups. The findings suggest that PE has a beneficial effect on trabecular bone in OVX rat model and this effect is possibly associated with stimulation of bone formation as well as inhibition of bone resorption.
文摘Oestrogens are not exclusive to the female gender but occur in moderate circulating levels of 25-70 pg ml^-1 in men, compared to 44- 153 pg ml^-1 in women. Arising from aromatisation of testosterone (T), oestrogen is considered to have many opposing physiological functions and the progressive T decline in the aging male is associated with relative and/or absolute increase in serum oestradiol (E2). Sexual disinterest and erectile dysfunction (ED) in the elderly may well be due to pathophysiological E2-T imbalance; the altered hormonal ratio may also explain the higher incidence of ED in hyperestrogenism or following exposure to environmental/plant oestrogens.
基金supported by CNCSIS-UEFISCSU Romania,project number PNII-IDEI 1337/2008
文摘Objective To evaluate the influence of an extract of Genista tinctoria L. herba (GT) or methylparaben (MP) on histopathological changes and 2 biomarkers of oxidative stress in rats subchronicly exposed to bisphenol A (BPA). Methods Adult female Wistar rats were orally exposed for 90 d to BPA (50 mg/kg), BPA+GT (35 mg isoflavones/kg) or BPA+MP (250 mg/kg). Plasma and tissue samples were taken from liver, kidney, thyroid, uterus, ovary, and mammary gland after 30, 60, and 90 d of exposure respectively. Lipid peroxidation and in vivo hydroxyl radical production were evaluated by histological analysis along with malondialdehyde and 2,3-dihydroxybenzoic acid detection. Results The severity of histopathological changes in liver and kidneys was lower after GT treatment than after BPA or BPA+MP treatment. A minimal thyroid receptor antagonist effect was only observed after BPA+MP treatment. The abnormal folliculogenesis increased in a time-dependent manner, and the number of corpus luteum decreased. No significant histological alterations were found in the uterus. The mammary gland displayed specific estrogen stimulation changes at all periods. Both MP and GT revealed antioxidant properties reducing lipid peroxidation and BPA-induced hydroxyl radical generation. Conclusion GT L. extract ameliorates the toxic effects of BPA and is proved to have antioxidant potential and antitoxic effect. MP has antioxidant properties, but has either no effect or exacerbates the BPA-induced histopathological changes.
文摘Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for this protection. Methods Human aortic endothelial cells subjected to normal (5mmol/L) or high glucose (25mmol/L) were treated with genistein at 0, 50, 100nmol/L. Parallel experiments were performed with 100nM 17b-estradiol, and also in the presence and absence of the pure anti-estrogen ICI-182,780 (100nmol/L). The effects on cell apoptotic DNA fragmentation were determined using cell death ELISA, and the effects on cellular proliferation were determined using tritiated thymidine incorporation assay. Estrogen receptor expression was detected by Taqman quantitative PCR. Results Genistein at 100nmol/L significantly reduced high glucose-induced DNA fragmentation, and reversed cell DNA synthesis inhibition (P <0.001) after 24 hours' incubation. The effect of genistein was completely blocked by ICI-182,780 administration. Estrogen receptor beta, but not alpha was found to be expressed in these cells. Conclusion Isoflavone genistein shows protection against high glucose-induced cell damage through estrogen receptor beta, reducing apoptotic DNA damage and protecting from the inhibition of cell proliferation.
基金Supported in part by Hibah Competition Grant Research of Faculty of PharmacyGadjah Mada University(Grant No.UGM/FA/851.d/M/05/01)
文摘Objective:To investigate the estrogenic effect of(8,9)-furanyl-pterocarpan-3-ol(FPC)on growth of human breast cancer T47D cells and the interactions between the FPC and tamoxifen(TAM),on the growth of estrogen receptor-dependent breast cancer T47D cells.Methods:The proliferation effect of FPC were conducted on T47D cells in vitro by MTT test.T47D cells were treated with FPC alone(0.01-200μmol/L)or in combination with TAM 20 nmol/L.Furthermore,the expression of ERαor c-Myc were also determined by immunohistochemistry.Results:The results indicated that administration of an anti-estrogen TAM showed growth inhibitory effect on T47D cells,wheraes co-administered with low concentration(less than 1μmol/L)of FPC attenuated to promote cell proliferation.In contrast,the combination of TAM with higher doses(more than 20μmol/L)of FPC showed growth inhibitory.This result was supported by immunocytochemistry studies that the administration of 20 nmol/L TAM down-regulated ER-αand c-Myc,but the combination of 20 nmol/L TAM and 1μmol/L FPC robustly up-regulated expression of ER-α.Thus,the reduced growth inhibition of TAM 20 nmol/L by FPC 1μmol/L on T47D cells may act via the modulation of ER-α.Conclusions:The findings indicate and suggest that FPC had estrogenic activity at low concentrations and anti-estrogenic effect that are likely to be regulated by c-Myc and estrogen receptors.We also confirm that low concentration of FPC attenuated the growth-inhibitory effects of TAM on mammary tumor prevention.Therefore,the present study suggests that caution is warranted regarding the consumption of dietary FPC by breast cancer patients while on TMA therapy.
基金supported by NKEA Research Grant Scheme(NRGS)(NH1113D018-2)。
文摘Objective:To investigate the bone-resorbing effect of demethylbelamcandaquinone B(Dmcq B)extracted from Marantodes pumilum var.alata on osteoclast differentiation in RAW264.7 cells.Methods:RAW264.7 macrophages were differentiated using RANKL into osteoclast-like cells.Then,they were treated with 10μg/mL Marantodes pumilum var.alata crude aqueous extract,5μg/mL dichloromethane fraction,and 0.6μg/mL Dmcq B and 0.06μg/mL estradiol.Tartrate-resistant acid phosphatase 5b(TRACP 5b)as an osteoclast phenotypic marker was determined by TRACP staining and TRACP 5b colometric assay,and bone-resorbing pits were examined.The gene expression of pro-inflammatory cytokines(TNF-αand IL-6)was measured.Moreover,the protein expressions of pro-inflammatory cytokines(TNF-αand IL-6)and estrogen receptors were evaluated.Results:Marantodes pumilum var.alata crude aqueous extract and Dmcq B inhibited RANKL-stimulated osteoclast differentiation as evidenced by size reduction of giant multinucleated osteoclast cells,decreased TRACP 5b activity as well as the subsiding of resorbed pit area compared with normal control.In addition,they reduced the gene and protein expressions of TNF-αand IL-6.Marantodes pumilum var.alata,Dmcq B,and estradiol treatments increased the protein expressions of estrogen receptors alpha and beta in osteoclasts.Conclusions:Marantodes pumilum var.alata and its active compound,Dmcq B can inhibit osteoclast differentiation.
文摘MRI provides a highly sensitive technique for early detection of abnormal breast tissue. It is useful for identifying a status of proliferation, angiogenesis, and microvascular permeability, which may indicate early breast neoplasm formation. We retrospectively studied 2005 breast MRI images from Taiwan Residents women and classified them as either healthy or unhealthy according to BI-RADS categories. A subgroup of our study patients had received estrogen supplements, containing estrogen components or phytoestrogen, for at least 3 months. These patients’ images were also classified into the healthy and unhealthy groups. These two groups were compared and a significant difference was found between them (P < 0.002). Comparison of the MRI images also identified certain cases that demonstrated a typical estrogen/phytoestrogen effect or a withdrawal effect. The overuse of estrogen or phytoestrogen supplements can increase breast glandular tissue proliferation, as reflected on MRI images. Such proliferation may increase the patient’s risk of future breast cancer.