Genistein-treated Group Research Articles

Evaluation of Genistein as a Mitochondrial Modulator and Its Effects on Sperm Quality.

Phytoestrogens, such as isoflavones, are bioactive compounds found in plants with defense and protection functions. In the human body, they simulate the behavior of the hormone estradiol and can modulate the function of the male hypothalamic-pituitary-gonadal axis. This study aims to describe the effects of genistein on sperm quality of Wistar rats (male/adult) after a short oral administration protocol (50 mg/day, for 5 days), focusing on mitochondrial function. No signs of toxicity were observed in the animals during the period. The testicular mass of rats from the genistein-treated group was lower than that from the control group. Isoflavone increased the number of viable Leydig and Sertoli cells, spermatogonia, and primary spermatocytes in the treated group. The rounded spermatid count was similar to the control group, and a decrease in elongated spermatids was observed in the treated group. Genistein treatment increased plasma testosterone levels in the treated group. To the best of our knowledge, this is the first report of an in vivo short protocol demonstrating that genistein administration stimulates the overall oxygen consumption in rat seminal samples. Therefore, genistein induced a pro-spermatogenesis effect, enhanced plasma testosterone levels, and increased oxygen consumption, improving sperm mitochondrial efficiency. Similar protocols can be explored in animal and human infertility issues.

Phloretin-induced suppression of oxidative and nitrosative stress attenuates doxorubicin-induced cardiotoxicity in rats

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.

Genistein alleviates renin-angiotensin system mediated vascular and kidney alterations in renovascular hypertensive rats

Genistein is a bioflavonoid mainly found in soybean. This study evaluated the effect of genistein on vascular dysfunction and kidney damage in two-kidney, one-clipped (2K1C) hypertensive rats. Male Sprague–Dawley-2K1C hypertensive rats were treated with genistein (40 or 80 mg/kg) or losartan 10 mg/kg (n = 8/group). Genistein reduced blood pressure, attenuated the increase in sympathetic nerve-mediated contractile response and endothelial dysfunction in the mesenteric vascular beds and aorta of 2K1C rats. Increases in the intensity of tyrosine hydroxylase (TH) in the mesentery and plasma norepinephrine (NE) were alleviated in the genistein-treated group. Genistein also improved renal dysfunction, hypertrophy of the non-clipped kidney (NCK) and atrophy of the clipped kidney (CK) in 2K1C rats. Upregulation of angiotensin II receptor type I (AT1R), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit 4 (Nox4) and Bcl2-associated X protein (BAX) and downregulation of B-cell lymphoma 2 (Bcl2) protein found in CK were restored by genistein. It also suppressed the overexpression of AT1R, transforming growth factor beta I (TGF-β1), smad2/3 and p-smad3 in NCK. Genistein reduced serum angiotensin converting enzyme (ACE) activity and plasma angiotensin II (Ang II) in 2K1C rats. Low levels of catalase activity as well as high levels of superoxide generation and malondialdehyde (MDA) in 2K1C rats were restored by genistein treatment. In conclusion, genistein suppressed renin-angiotensin system-mediated sympathetic activation and oxidative stress in 2K1C rats. It alleviated renal atrophy in CK via modulation of AT1R/NADPH oxidase/Bcl-2/BAX pathways and hypertrophy in NCK via AT1R/TGF-β1/smad-dependent signalling pathways.

Diabetic neovascularization defects in the retina are improved by genistein supplementation in the ovariectomized rat.

Genistein seems to have a protective and therapeutic effect on conditions associated with neovascular growth in the retina. This study investigated the angiogenesis, antioxidant, and anti-inflammatory effect of genistein on the retinas in ovariectomized diabetic rats. In this study, 40 female albino Wistar rats were divided into four groups (n = 8 per group): sham, ovariectomized group (OVX), OVX + diabetes (OVX.D), and OVX.D + genistein (OVX.D.G). OVX induced by removal of bilateral ovaries and then high-fat diet (HFD) and a low dose of streptozotocin (STZ) (1mg/kg; intraperitoneal (IP) injection) was used for diabetes induction (OVX.D) with 8weeks of genistein treatment (OVX.D.G). At the end of 8weeks, the retina was removed under anesthesia. The samples were used to measure extracellular signal-regulated kinase (ERK), matrix metalloproteinase2 (MMP-2), vascular endothelial growth factor (VEGF), and nuclear factor NF-kappa-B (NF-κB) by western blotting and inflammatory factors ELISA and oxidative stress. Measurements of glutathione (GSH) and malondialdehyde (MDA) showed that OVX and especially OVX.D significantly decreased GSH and increased MDA level in the retina, but genistein reversed these effects in OVX.D.G groups. Also, OVX and OVX.D significantly increased VEGF, MMP-2, p-ERK, NF-κB, interleukin-1beta (IL-1β), and tumor necrosis factor alpha (TNFα) expression in the retina of OVX and OVX.D groups in comparison to the sham group (p < 0.05). However, a significant reduction of these proteins was observed in the genistein-treated group (p < 0.05). In conclusion, bilateral ovariectomy and subsequently estrogen deficiency caused the development of inflammation, neovascularization, and then retinopathy in STZ-induced diabetic ovariectomized rats. On the basis of the results, genistein administration may be a practical approach for improving symptoms and complications of ovariectomized diabetic retinopathy.

Genistein Prevents Nitric Oxide Deficiency-Induced Cardiac Dysfunction and Remodeling in Rats.

Genistein is an isoflavone found in soybeans. This study evaluates the protective effects of genistein on Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertension, cardiac remodeling, and dysfunction in rats. Male Wistar rats were treated with L-NAME 40 mg/kg/day together for 5 weeks, with or without genistein at a dose of 40 or 80 mg/kg/day or lisinopril 5 mg/kg/day (n = 8 per group). Genistein prevented L-NAME-induced hypertension in rats. Increases in the left ventricular weight, metalloproteinase-2, metalloproteinase-9, and collagen type I intensity were observed in L-NAME rats, and these changes were attenuated in the genistein-treated group. Genistein reduced circulating angiotensin-converting enzyme activity and angiotensin II concentrations in L-NAME rats. L-NAME increased plasma and cardiac malondialdehyde and vascular superoxide generations, as well as reductions of serum and cardiac catalase activities in rats. Plasma nitrate/nitrite were protected in the genistein-treated group. Genistein prevented the L-NAME-induced overexpression of angiotensin II receptor type I (AT1R), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit 2 (gp91phox), and transforming growth factor beta I (TGF-β1) in hypertensive rats. In conclusion, genistein exhibited a cardioprotective effect in hypertensive rats in this study. The molecular mechanisms might be mediated by suppression of oxidative stress through the Ang II/AT1R/NADPH oxidase/TGF-β1 signaling pathway.

Estrogenic properties of genistein acting on FSHR and LHR in rats with PCOS.

The purpose of the study was to study the activity of the phytoestrogen genistein (GEN) act- ing on FSHR and LHR in rat ovaries with polycystic ovary syndrome (PCOS). Sixty rats were di- vided into six groups. Rats in the dose group received genistein at a concentration of either 5 (low genistein dose group, L-gen), 10 (middle genistein dose group, M-Gen) or 20 (high genistein dose group, H-Gen) mg per kg of body weight per day. Estrogen group (EG, received 0.5 mg/kg Dieth- ylstilbestrol). Concentration of sex hormones in serum was quantified by enzyme-linked immuno- sorbent assay (ELISA). Expressions of follicle-stimulating hormone receptor (FSHR) and lutein- izing hormone receptor (LHR) protein were determined by immunohistochemistry. Treatment with genistein resulted in a strong stimulation of the concentration of sex hormone in serum. The concentration of progesterone and FSH was significantly higher in H-Gen when compared to the PCOS model control group (MG) (P ⟨ 0.01). In contrast, the concentration of testosterone, LH and the ratio of LH/FSH decreased in GEN treatment groups compared to MG, the effect was statistically significant, tested by the ANOVA test (p⟨0.01). For hormone receptor activity, treat- ment with genistein resulted in an improvement of ovarian function with LHR protein expression being enhanced and FSHR protein expression being suppressed. Our results demonstrate that Genistein played a significant role in regulating FSH and LH receptor expression to improve perimenopausal ovarian and uterine function.

Genistein induces apoptosis in vitro and has antitumor activity against human leukemia HL-60 cancer cell xenograft growth in vivo.

Genistein, a major isoflavone compound in soybeans, has been shown to have biological activities including anti-cancer activates. In the present, we investigated the anti-leukemia activity of genistein on HL-60 cells in vitro. The percentage of viable cell, cell cycle distribution, apoptotic cell death, reactive oxygen species (ROS), and Ca2+ production and the level of ΔΨm were measured by flow cytometric assay. Cell apoptosis and endoplasmic reticulum (ER) stress associated protein expressions were examined by Western blotting assay. Calpain 1, GRP78, and GADD153 expression were measured by confocal laser microscopy. Results indicated that genistein-induced cell morphological changes, decreased the total viable cells, induced G2 /M phase arrest and DNA damage and fragmentation (cell apoptosis) in HL-60 cells. Genistein promoted ROS and Ca2+ productions and decreased the level of ΔΨm in HL-60 cells. Western blotting assay demonstrated that genistein increased ER stress-associated protein expression such as IRE-1α, Calpain 1, GRP78, GADD153, caspase-7, caspase-4, and ATF-6α at 20-50 μM treatment and increased apoptosis associated protein expression such as pro-apoptotic protein Bax, PARP-cleavage, caspase-9, and -3, but decreased anti-apoptotic protein such as Bcl-2 and Bid in HL-60 cells. Calpain 1, GRP78, and GADD153 were increased in HL-60 cells after exposure to 40 μM of genistein. In animal xenografted model, mice were intraperitoneally injected with genistein (0, 0.2, and 0.4 mg/kg) for 28 days and the body weight and tumor volume were recorded. Results showed that genistein did not affect the body weights but significantly reduced the tumor weight in 0.4 mg/kg genistein-treated group. Genistein also increased the expressions of ATF-6α, GRP78, Bax, Bad, and Bak in tumor. In conclusion, genistein decreased cell number through G2 /M phase arrest and the induction of cell apoptosis through ER stress- and mitochondria-dependent pathways in HL-60 cells and suppressed tumor properties in vivo.

Preventive effect of genistein on AOM/DSS-induced colonic neoplasm by modulating the PI3K/AKT/FOXO3 signaling pathway in mice fed a high-fat diet

Colon cancer is one of the most prevalent malignancies in the world. The incidence of colon cancer is on the rise, which seriously affects people's physical and mental health. Genistein, the predominant isoflavone found in soy products, has been shown to inhibit carcinogenesis in animal models. However, the molecular mechanisms involved in genistein preventing carcinogenesis are still uncharacterized. This study was aimed to evaluate the preventive effect of genistein-rich diet on azoxymethane/dextran sulfate sodium (AOM/DSS) induced colon cancer in high-fat mice. Contrasted with control group, the addition of genistein can ward off colon cancer. The expression of COX-2, TNF-α and FRAT1 mRNA has decreased in genistein-treated group. Furthermore, genistein-rich diet has inhibited the viability of colon cancer via regulating the expression of PI3K, FOXO3 and AKT. It has been suggested that genistein prevent the colonic neoplasms growth by modulating the PI3K/FOXO3/AKT signaling pathway in mice fed with a high-fat diet.

Genistein has the function of alleviating and treating disseminated intravascular coagulation caused by lipopolysaccharide.

Symptoms of disseminated intravascular coagulation (DIC) include thromboembolism, acute attrition bleeding and multiple organ failure. Genistein isolated from leguminous plants has been shown to be effective in oxidation resistance and tumor inhibition. The present study was designed to evaluate the therapeutic effects of genistein in DIC and preliminarily discuss the mechanisms regarding the anti-inflammatory and anticoagulant effect of genistein. Swiss mice were randomly divided into the following groups-(1) lipopolysaccharide (LPS), (2) genistein, (3) dimethyl sulfoxide (DMSO, the non-major solvent component of genistein), (4) DMSO + LPS, (5) saline control group, and (6) heparin control group. LPS was injected intraperitoneally in all the groups except the DMSO group and saline control group. Our results significantly showed that the morphological structure of the liver and kidneys was improved and the fiber protein deposition was decreased, with remarkable improvement of coagulation indicators, function indicators and inflammatory factors in the genistein treatment group compared with the LPS group. In vitro phosphorylated-nuclear factor kappa-light-chain-enhancer of activated B cells and interleukin-6 were obviously reduced in the genistein treatment group compared with the LPS group in RAW 264.7 murine macrophage cells. All the results suggested that genistein has the function of alleviating and treating LPS-induced DIC by anti-inflammatory and anticoagulation effects. We tentatively propose that genistein is a potential drug for auxiliary treatment of DIC.

8-Prenylgenistein, a prenylated genistein derivative, exerted tissue selective osteoprotective effects in ovariectomized mice.

Our previous study reported that the in vitro osteogenic effects of 8-prenylgenistein (8PG) were more potent than its parent compound genistein. This study aimed to evaluate the osteoprotective effects of 8PG in ovariectomized (OVX) mice as well as to characterize its estrogenic effects in uterus. Mature OVX mice were treated with phytoestrogen-free diet containing 8PG or genistein. Trabecular bone mass and most of the micro-structural parameters were ameliorated at the distal femoral metaphysis in OVX mice upon treatment with genistein and both doses of 8PG. The beneficial effects of 8PG on trabecular bone were confirmed by safranin O and ABHO staining. 8PG markedly inhibited the ovariectomy-induced mRNA expressions of RANKL/OPG, ALP, COL, OCN, cathepsin K and ER-α in bone. In contrast, genistein further increased the ovariectomy-induced ER-α expression in bone. The uterus index was increased in genistein-treated group. Genistein up-regulated the expression of ER-α and PR, while 8PG significantly down-regulated the ER-α and C3 expression in uterus of OVX mice. Moreover, genistein, but not 8PG, increased expressions of ER-α, PCNA and C3 in Ishikawa cell. This study suggested that 8PG improved trabecular bone properties in OVX mice without exerting uterotrophic effects and its estrogenic actions were distinct from those of genistein.

Synergistic Effects of Genistein and Zinc on Bone Metabolism and the Femoral Metaphyseal Histomorphology in the Ovariectomized Rats.

In this study, we evaluated the synergistic effects of genistein and zinc on bone metabolism, bone mineral density, and the femoral metaphyseal histomorphology in the ovariectomized rats. Sixty female Sprague-Dawley rats, aged 13weeks, were divided into sham-operated group (SHAM), ovariectomized group (OVX), genistein-treated group (OVX-Gen), zinc-treated group (OVX-Zn), genistein combined zinc-treated group (OVX-Gen-Zn), and 17β-estradiol-treated group (OVX-E) (n=10). Genistein, zinc, and 17β-estradiol injections were started immediately after OVX and continued for 10weeks. The OVX-Gen group was subcutaneous injections of genistein (5mg/kg once every day). The OVX-Zn group was given intragastric ZnSO4 (0.25mg/kg once every day) after bilateral ovariectomy. The OVX-Gen-Zn group was subcutaneous injections of genistein (5mg/kg), at the same time intragastric ZnSO4 (0.25mg/kg once every day). OVX-E group were intraperitoneally injected with 17β-estradiol (10μg/kg) once every other day. The results showed that genistein and zinc did not alter body weight in OVX rats. The soluble ZnSO4 had no effect to uterus weight loss. Genistein and zinc supplementation significantly increased the BMD of the femur and lumbar spine in OVX rats (P<0.05, vs. OVX control group). The BMD of the lumbar spine and femur in the OVX-Gen-Zn group is higher than that in the OVX-Gen and OVX-Zn groups (P<0.05), and there were no differences of BMD among the OVX-Gen-Zn, OVX-E, and SHAM groups (P>0.05). The femoral metaphyseal morphology and bone histomorphometric parameters revealed that the trabecular volume and thickness in the OVX-Gen-Zn and OVX-E groups were similar to that of SHAM group, and the OVX-Gen-Zn group had more trabecular volume than the OVX-Gen and OVX-Zn groups. Serum zinc was found to be significantly reduced in the OVX group when compared with SHAM. Serum zinc levels were enhanced in the OVX-Zn, OVX-Gen-Zn, and OVX-E groups and restored to normal levels. Serum calcium and serum phosphorus in the OVX-Gen-Zn group was greater than that in the OVX-Gen and OVX-Zn groups (P<0.05); the serum calcium, phosphorus, and ALP in the OVX-Gen-Zn group were similar to that of SHAM and OVX-E groups (P>0.05). The OVX group had higher osteocalcin, CTX, and RANKL than the SHAM group (P<0.01). They were lower in the OVX-Gen and OVX-Zn groups (P<0.05), and they were significantly lower in the OVX-Gen-Zn and OVX-E groups, than in the OVX group. There were no significant differences of osteocalcin, CTX, and RANKL among the OVX-Gen-Zn, OVX-E, and SHAM groups (P>0.05). OPG and OPG/RANKL ratios were significantly higher in the OVX-Gen and OVX-Zn groups than that in the OVX group (P<0.05). The OPG and OPG/RANKL ratio in the OVX-Gen-Zn group is higher than that in the OVX-Gen and OVX-Zn groups (P<0.05, vs. OVX-Gen group; P<0.01, vs. OVX-Zn group). The differences of the OPG and OPG/RANKL ratios between the OVX-Gen-Zn, OVX-E, and the SHAM groups were not significant (P>0.05). The results above indicate that the genistein and zinc have synergistic effects on both stimulation of bone formation and suppression of bone resorption in ovariectomized rats, thereby increasing bone mass.

Genistein Ameliorates Ischemia/Reperfusion-Induced Renal Injury in a SIRT1-Dependent Manner.

Renal ischemia/reperfusion (I/R) injury continues to be a complicated situation in clinical practice. Genistein, the main isoflavone found in soy products, is known to possess a wide spectrum of biochemical and pharmacological activities. However, the protective effect of genistein on renal I/R injury has not been well investigated. In the current study, we explore whether genistein exhibits its renal-protective effects through SIRT1 (Sirtuin 1) in I/R-induced mice model. We found the treatment of genistein significantly reduced renal I/R-induced cell death, simultaneously stimulating renal cell proliferation. Meanwhile, SIRT1 expression was up-regulated following the administration of genistein in renal region. Furthermore, pharmacological inhibition or shRNA-mediated depletion of SIRT1 significantly reversed the protective effect of genistein on renal dysfunction, cellular damage, apoptosis, and proliferation following I/R injury, suggesting an indispensible role of the increased SIRT1 expression and activity in this process. Meanwhile, the reduced p53 and p21 expression and increased PCNA (Proliferating Cell Nuclear Antigen) expression were blocked after the depletion of SIRT1 compared with the genistein treatment group in the renal I/R process. Hence, our results provided further experimental basis for the potential use of genistein for the treatment of kidney disease with deficiency of SIRT1 activity.

Genistein attenuates monocrotaline-induced pulmonary arterial hypertension in rats by activating PI3K/Akt/eNOS signaling.

Phytoestrogen genistein may be useful to treat pulmonary arterial hypertension (PAH). However, its mechanism is still not clear. The aim of the present study was to confirm the therapeutic effects of phytoestrogen genistein on PAH in monocrotaline-induced rat model and to explore its mechanism. Sprague-Dawley male rats were randomly divided into 4 groups: control group (n=8), PAH group (n=8), genistein treament group with three different doses (n=8 in each dose group) and group of PI3K inhibitor LY294002. The rat model of PAH was induced by monocrotaline (MCT). The situation of survival of rats was observed. Pathological studies of lung and heart tissues were performed. Western-blot detection of P-Akt and P-eNOS expression levels in lung tissue was carried out. Nitrate reductase analysis was used to measure nitric oxide (NO) in lung tissue. Genistein treatment resulted in significant improvement in the speed of tricuspid regurgitation, diameter of pulmonary artery, mean pulmonary artery pressure and right ventricular hypertrophy index. Genistein treatment also resulted in significant improvement in the stenosis of pulmonary artery, proliferation of smooth muscle, right ventricular hypertrophy and myocardial hypertrophy. These therapeutic effects were more obvious with increasing dose of genistein. After genistein treatment, amelioration in survival rates of PAH rats was observed. PI3K inhibitor LY294002 could block these therapeutic effects. In rat lung tissue, P-Akt, P-eNOS and NO expressions were increased significantly in genistein treatment group when compared with PAH group (p<0.05, respectively). The increase in expression level of P-Akt, P-eNOS and NO was correlated with genistein dose. P-Akt, P-eNOS and NO expressions in lung tissue increased slightly in the PI3K inhibitor LY294002 group when compared with PAH group, but the difference was not statistically significant (p>0.05). We confirmed that genistein could relax pulmonary vascular resistance, reduce pulmonary artery pressure, improve right heart function and ameliorate survival rate in the rat model of PAH. Our study suggested that its mechanism was related with PI3K/Akt/eNOS signal pathway. Phytoestrogen genistein may become a new and effective drug for patients with PAH.

Genistein suppresses the mitochondrial apoptotic pathway in hippocampal neurons in rats with Alzheimer's disease.

Genistein is effective against amyloid-β toxicity, but the underlying mechanisms are unclear. We hypothesized that genistein may protect neurons by inhibiting the mitochondrial apoptotic pathway, and thereby play a role in the prevention of Alzheimer's disease. A rat model of Alzheimer's disease was established by intraperitoneal injection of D-galactose and intracerebral injection of amyloid-β peptide (25-35). In the genistein treatment groups, a 7-day pretreatment with genistein (10, 30, 90 mg/kg) was given prior to establishing Alzheimer's disease model, for 49 consecutive days. Terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling assay demonstrated a reduction in apoptosis in the hippocampus of rats treated with genistein. Western blot analysis showed that expression levels of capase-3, Bax and cytochrome c were decreased compared with the model group. Furthermore, immunohistochemical staining revealed reductions in cytochrome c and Bax immunoreactivity in these rats. Morris water maze revealed a substantial shortening of escape latency by genistein in Alzheimer's disease rats. These findings suggest that genistein decreases neuronal loss in the hippocampus, and improves learning and memory ability. The neuroprotective effects of genistein are associated with the inhibition of the mitochondrial apoptotic pathway, as shown by its ability to reduce levels of caspase-3, Bax and cytochrome c.

The study of genistein attenuating genioglossus muscle fatigue under chronic intermittent hypoxia

To investigate the effects of genistein on genioglossus muscle function and nuclear factor erythroid 2 related factor 2(Nrf-2)/antioxidant responsive element(ARE) signaling pathway in rats under chronic intermittent hypoxia(CIH) condition in order to find medication treatment of obstructive sleep apnea/hyponea syndrome. Thirty female Sprague-Dawley(SD) rats (8 weeks old) were randomly(random number table) divided into three groups 1 week after ovariectomy: control group(NC group), CIH group, and CIH+genistein treatment group(T group). Rats in the latter two groups were exposed to CIH for 8 h/d for 5 weeks. Electrophysiological method was used to detect the change of genioglossus muscle function, and real-time reverse transcription(RT)-PCR and Western blotting were used to determine the level of Nrf-2 gene and protein. Compared to NC group, the contractive properties of genioglossus muscle fatigue test at every time set was significantly decreased in CIH group(P<0.05). Compared to CIH group, the contractive properties was significantly increased in T group(P<0.05). The level of Nrf-2 gene and protein were less in CIH group(0.54±0.11 and 0.35±0.13) than in NC group(1.00±0.001.00±0.00)(P<0.05). Compared to CIH group the level of Nrf-2 gene and protein were increased in T group (0.76 ± 0.16 and 0.63 ± 0.14) (P<0.05), however, it was still less than the level in NC group(P<0.05). CIH attenuates genioglossus muscle fatigue resistance under chronic intermittent hypoxia through Nrf-2/ARE signaling pathway. Genistein protects genioglossus muscle function through up-regulation of the level of Nrf-2 gene and protein.

Effect of genistein added to bull semen after thawing on pronuclear and sperm quality

The aim of this research was to study the effect of different genistein treatments on bull sperm after thawing on pronuclear formation after in vitro fertilization (IVF) and on different sperm quality variables. Three experiments were performed. In Experiment 1, three treatments (Control, sperm incubation for 1h at 37°C with or without genistein) and two sperm concentrations during IVF (1 or 3×106sperm/mL) were evaluated to study the influence of genistein on pronuclear formation (PNF). Sperm incubation for 1h before IVF reduced PNF regardless of sperm concentration. However, after sperm incubation and with 3×106sperm/mL in IVF, the genistein treatment group had greater fertilization rates than the untreated group. In Experiment 2, six treatments plus the control group were performed to study the effect of genistein (presence or not) and incubation conditions (30min at 37°C, 1h at 27°C or at 37°C) on PNF using 3×106sperm/mL for IVF. When incubation time was reduced to 30min, PNF rate from the genistein treatment group was no different from either the control group or in the group in which incubation occurred for 1h at 27°C. In Experiment 3, the effect of several genistein treatments (control; genistein treatment for 30min of incubation at 37°C; genistein treatment for 1h of incubation at 27°C) on sperm motility, viability and DNA fragmentation were evaluated. Genistein did not improve sperm motility and, depending on the experimental group or time, it either reduced or had no effect on sperm motility. Genistein treatment did not improve sperm viability after 5h of incubation. However, genistein treatment for 1h at 27°C decreased sperm DNA fragmentation compared with the control group after 5h of sperm incubation. In conclusion, the treatment of bull sperm with genistein for 1h at 27°C could decrease sperm DNA fragmentation, although PNF rate after IVF and sperm motility were reduced.

Inhibitory Effect of Genistein on PLC/PRF5 Hepatocellular Carcinoma Cell Line.

Background:Natural compounds including flavonoids like genistein (GE) are able to inhibit cell proliferation and induce apoptosis. GE is the main representative of these groups. GE inhibits carcinogenic tumors such as colon, stomach, lung, and pancreas tumors. The aim of the present study was to analyze the apoptotic effect of GE in the hepatocellular carcinoma (HCC) PLC/PRF5 cell line.Methods:Cells were treated with various doses of GE (1, 5, 10, 25, 50, 75, and 100 μM/L) at different times (24, 48, and 72 h) and the MTT assay was commonly used. Furthermore, cells were treated with single dose of GE (25 μM) at different times and flow cytometry was performed.Results:GE inhibited the growth of liver cancer cells significantly with a time- and dose-dependent manner. The percentage of living cells in GE treatment groups with a concentration of 25 μM at different times were 53, 48 and 47%, respectively (P < 0.001). Result of flow cytometry demonstrated that GE at a 25 μM concentration induces apoptosis significantly in a time-dependent manner. The percentage of apoptotic cells at different times were 44, 56, and 60%, respectively (P < 0.001).Conclusions:GE can significantly inhibit the growth of HCC cells and plays a significant role in apoptosis of this cell line.

Genistein Protects Female Nonobese Diabetic Mice from Developing Type 1 Diabetes When Fed a Soy- and Alfalfa-free Diet

The objective of this study was to determine the effects of the phytoestrogen genistein (GEN) on the time of onset and/or the incidence of type 1 diabetes (T1D) in female nonobese diabetic (NOD) mice, when administered GEN by gavage once every day for up to 180 days. Five groups of mice (approximately 24 animals/group; 6-7 weeks of age) were included: naive control, vehicle control (25 mM Na2CO3 in water), and 3 GEN treatment groups (2 mg/kg, 6 mg/kg, and 20 mg/kg). Mice were maintained on a soy- and alfalfa-free diet (5K96) during the study and were monitored for blood glucose changes every week. When compared to the vehicle control, exposure to 2-mg/kg GEN produced significant decreases ranging from 55 to 79% in the total incidences of diabetes (blood glucose ≥ 250 mg/dl) and severe diabetes (blood glucose ≥ 400 mg/dl) starting at week 14 of the study. However, during the later stages of the study (i.e., after week 23), the 2-mg/kg dose had no effect on disease incidence. In animals treated with 6-mg/kg and 20-mg/kg GEN, significant decreases in the total incidence of diabetes were observed starting at week 16, while the incidence of severe diabetes was significantly decreased with the changes being observed initially at weeks 18 and 17 for the 6-mg/kg and 20-mg/kg GEN treatment groups, respectively. Several lines of evidence, including histopathological analysis, suggested that GEN protected the pancreas from autoimmune destruction. However, this protective effect of GEN was absent when female NOD mice were maintained on NTP-2000 rodent diet, which contained 5% soybean meal and 7.5% alfalfa meal (the total concentrations of phytoestrogens ranged between 95 and 134 mg/kg). In summary, oral dosing of GEN reduced the incidence and increased the time to onset of T1D in female NOD mice but only when fed a soy- and alfalfa-free diet.

The effects of genistein on estrogen receptor expression, cell proliferation, and apoptosis in endometriosis cell culture

Objectives: This study aimed to investigate whether genistein is able to inhibit cell proliferation and expression of estrogenic receptors, and to induce apoptosis in endometriosis cells. Methods: Confluent primary endometriosis cells were divided into seven groups, including control group and genistein treatment group at doses of 5, 10, 20, 30, 40 and 50 µmol/l. The times of incubation were 6, 24 and 48 hours. Four replications are applied in each group. Expression of estrogen receptor-α and estrogen receptor-β and level of proliferation cells in cells were measured using flow cytometry. Level of apoptosis cells and Bax were measured by enzyme-linked immunosorbent technique. Results: In 6 hours of treatment, the expression of estrogen receptor-α and estrogen receptor-β significantly decreased at all doses of genistein compared with control group. The expression of estrogen receptor-α was significantly reduced in 5 until 40 µM of 24 hours genistein treatment groups in comparison to control group, but estrogen receptor-β was not significantly different. In 48 hours of treatment, the expression of estrogen receptor-α and estrogen receptor-β were significantly lower in genistein-treated groups at doses of 40 µM and 20-50 µM, respectively, compared to control group. With 6 hours of treatment, the level of KI-67 and apoptosis significantly decreased in 50 µM genistein treatment group compared to control group. The expression of KI-67 significantly reduced at all doses of 24 hours genistein treatment compared to control group. In 48 hours of treatment, the level of KI-67 and apoptosis were significantly lower in 40 µM genistein treatment group compared to control group. The level of apoptosis was significantly higher in genistein treatment group compared to control group in 24 hours 50 µM genistein treatment group. Level of Bax significantly increased in genistein treatment at the doses from 10 until 50 µM compared to that of control group. Conclusion: Genistein inhibits endometrial cell proliferation and estrogen receptor expression, and induces apoptosis in endometriosis cell culture.

Postweaning dietary genistein exposure advances puberty without significantly affecting early pregnancy in C57BL/6J female mice

An epidemiological study indicates higher plasma level of genistein in girls with earlier puberty. This study tests the hypothesis in C57BL/6J mice that postweaning (peripubertal) dietary genistein exposure could result in earlier puberty in females assessed by vaginal opening, estrous cyclicity, corpus luteum and mammary gland development. Newly weaned female mice were fed with 0, 5, 100, or 500ppm genistein diets. Decreased age at vaginal opening, increased length on estrus stage, and accelerated mammary gland development were detected in 100 and 500ppm genistein-treated groups. Increased presence of corpus luteum was found in 5ppm genistein-treated group at 6 weeks old only. Increased expression of epithelial-specific genes but not that of ERα or ERβ was detected in 500ppm genistein-treated mammary glands at 5 weeks old. No significant adverse effect on embryo implantation was observed. These data demonstrate causal effect of dietary genistein on earlier puberty in female mice.