Oral Administration Of Genistein Research Articles

Impact of highly phospholipid-containing lipid nanocarriers on oral bioavailability and pharmacodynamics performance of genistein

Oxidative stress is a leading cause of different diseases. Genistein is a valuable bioflavonoid possessing antioxidant and anti-inflammatory activity but unfortunately, it suffers from low aqueous solubility, extremely poor bioavailability and first pass effect when used in its pure state. The aim of this work was to formulate and characterize genistein-loaded highly phospholipid-containing lipid nanocarriers to improve oral bioavailability and pharmacodynamic performance. Lipid nanocarriers were prepared by the emulsification/sonication technique. The influence of phospholipid percentage (1%–10%) on physicochemical properties, drug release and stability was investigated. The particle size, zeta potential and EE% were in ranges from 211.9 ± 21.6 to 342.3 ± 7.9 nm, −11.6 ± 1.7 to −19.4 ± 3.1 mV and 78.5 ± 4.7% to 92.2 ± 1.9%, respectively. Drug release was less predominant in the case of SLN formulations when compared to corresponding NLC formulations. High phospholipid percentage produced less stable formulations in terms of particle size growth, gelation and heterogeneous particle distributions. DSC, FT-IR and XRD tools revealed that genistein has existed in an amorphous form in NLC4. The bioavailability of NLC4 was approximately 2.6-fold greater than that of conventional suspension. Additionally, lipid peroxidation in liver homogenate and histopathological alterations in liver and kidney sections were particularly improved, providing a promising strategy for oral administration of genistein.

Neuroprotective effect of genistein on cognitive impairment in vascular dementia experimental mice model

The present study aims to determine the neuroprotective efficacy of genistein on vascular dementia in experimental model mice and explore the underlying mechanisms. To induce vascular dementia, chronic bilateral common carotid artery occlusion was performed on female mice brain by occluding both common carotid arteries for 30 min followed by 24 h reperfusion to induce neuronal injury. After surgery, the mice were treated daily by oral administration of genistein (5.0, and 10.0 mg/kg, i.p., o.d.) for one months. The cognition function of treated mice, were evaluated by Morris Water Maze (MWM) test, neurological functions measured as short-term memory and motor performance. In addition, cerebral infarct size, oxidative damage, mitochondrial activity in terms of neuronal apoptosis and cellular viability, Nissl and TUNEL staining were chosen to assess neuronal damage within the hippocampal CA1 area. In present study, there was an increase in cognitive impairment and neuronal damages within CA1 hippocampal subregion caused by chronic cerebral hypoperfusion. Genistein administration significantly counteracted cognitive impairment and re-established motor performance in vascular dementia in mice. Genistein was able to prevent cognitive deficits, and reversed CCH-induced hippocampal neuronal loss and apoptosis. Genistein treatment significantly reduced neuronal apoptosis and increased cellular viability, almost completely suppressed the circulating dipeptidyl peptidase-4 activity, and enhanced glucagon-like peptide-1 concentration in vascular dementia in experimental model mice. This study suggests that genistein has potent neuroprotective activity against chronic cerebral hypoperfusion and may be considered as a potential treatment for cognitive deficits and neuronal injury in the hippocampal CA1 area.

Effects of soy isoflavone genistein on lipid profile and hepatic steatosis in high-fat-fed Wistar rats

Background: Hyperlipidemia is a major cause of atherosclerosis-induced conditions such as coronary heart disease, ischemic cerebrovascular disease, and peripheral vascular disease. Due to various adverse effects with the current pharmacological therapy, many plant-derived compounds are being tested to lower serum lipid levels. Genistein, a soy isoflavone, showed promising results in several studies. Aims and Objectives: The study aimed to evaluate the effectiveness of genistein on serum lipid profile and its hepatoprotective activity in hyperlipidemic male albino Wistar rats. Materials and Methods: Thirty-six male Wistar rats were randomly divided into six groups. Animals were given high cholesterol diet (0.75% cholesterol + 1.5% bile salt) to induce hyperlipidemia. The animals were treated with atorvastatin (10 mg/kg oral) and genistein (1 mg/kg oral and 5 mg/kg oral) once daily for a period of 30 days. Blood samples were collected for biochemical analysis of lipoproteins and a portion of liver tissue was taken for histopathological examination. Statistical analysis was performed by one-way analysis of variance test followed by post hoc Dunnett’s multiple comparison test. P < 0.05 was considered statistically significant. Results: Oral administration of genistein showed a significant reduction in serum total cholesterol, triglycerides, and low-density lipoprotein levels. Histopathological examination of liver showed a significant reduction in hepatic steatosis (P < 0.001) with no inflammatory changes as compared to high cholesterol-treated rats. Conclusion: The present study demonstrated significant hypolipidemic and hepatoprotective activities of genistein at a dose of 5 mg/kg in the experimental rats.

Phytochemical genistein promotes pancreatic beta‐cell survival and exerts anti‐diabetic effect via GPR30‐mediated mechanism (1045.44)

Loss of pancreatic beta‐cell mass is central to the development of both type 1 and type 2 diabetes (T2D). Chronic hyperglycemia and hyperlipidemia cause beta‐cell apoptosis, thereby contributing to the pathogenesis of T2D. We investigated the effects of phytochemical genistein on apoptosis and function of beta‐cells and further determined the mechanism underlying its actions ex vivo and in vivo. We show that genistein promoted viability, inhibited apoptosis, and reduced caspase‐3 activity of INS1 beta‐cells and human and mouse islets chronically exposed to palmitate (0.5 mM) and high glucose (HG, 20 mM). In addition, exposure of beta‐cells to genistein activated PI3K/Akt signaling and up‐regulated anti‐apoptotic protein Bcl‐2 expression. The anti‐apoptotic effect of genistein is independent of classical estrogen receptor‐mediated signaling machinery, but it may be achieved through the G‐protein‐coupled receptor GPR30‐mediated activation of cAMP signaling. Oral administration of genistein (50 mg/kg BW/day) improved hyperglycemia, glucose tolerance, and blood insulin levels in wide‐type obese diabetic mice, but these effects were abolished in GPR30 null mice. These findings demonstrate that genistein exerts anti‐diabetic effect and promotes beta‐cell survival via GPR30‐mediated signaling pathway.Grant Funding Source: supported by grants from the NCCAM of NIH (R01AT007077) and the ADA (7‐11‐BS‐84) to DL.

Role of Dietary Soybean Genistein in Osteoporosis Prevention

Bone homeostasis is regulated through osteoclasts and osteoblasts. Osteoporosis, which is induced with its accompanying decrease in bone mass with increasing age, is widely recognized as a major public heath problem. Bone loss may be due to decreased osteoblastic bone formation and increased osteoclastic bone resorption. There is growing evidence that nutritional and food factors may play a part in the prevention of bone loss with aging and have been to be worthy of notice in the prevention of osteoporsis. Genistein, which is contained in soybeans, has been shown to have a stimulative effect on osteoblastic bone formation and a suppressive effect on osteoclastic bone resorption, thereby increasing bone mass. This factor has a regulative effect on protein synthesis and gene expression, which are related to bone formation in osteoblastic cells and bone resorption in osteoclastic cells. Oral administration of genistein has been shown to prevent on bone loss in ovariectomized rats, an animal model for osteoporosis, indicating a role in the prevention of osteoporosis. Intake of dietary soybean genistein has been shown to have a preventive effect on osteoporosis in human subjects, suggesting a role in the prevention of bone loss. This review discusses a role of dietary soybean genistein in osteoporosis prevention.

Association of multidrug resistance-associated protein 2 single nucleotide polymorphism rs12762549 with the basal plasma levels of phase II metabolites of isoflavonoids in healthy Japanese individuals

Multidrug resistance-associated protein 2 (MRP2; ABCC2) is an ATP-binding cassette transporter that mediates the efflux of anionic drugs and phase II metabolites. Our aim was to elucidate the impact of a single nucleotide polymorphism, rs12762549 (G>C), on the in-vivo activity of MRP2. Plasma specimens collected from 18 healthy volunteers were subjected to an untargeted metabolomic analysis using liquid chromatography-mass spectrometry. The role of MRP2 in the disposition of substances of interest was then examined in vivo in Mrp2-deficient mutant rats (Eisai hyperbilirubinemic rats; EHBRs) and in vitro in human MRP2-expressing membrane vesicles. A multivariate analysis model using liquid chromatography-mass spectrometry data sets successfully differentiated the GG and the CC genotypes of rs12762549. The C allele is associated with the basal plasma levels of the five phase II metabolites of genistein and dihydrogenistein. Such phase II metabolites were also accumulated in EHBR, compared with normal rats, partly because of the reduced biliary excretion. Following oral administration of genistein and daidzein, the plasma concentrations of total genistein and total daidzein, which were mainly accounted for by sulfoglucuronide conjugates, were markedly higher in EHBR than in normal rats. ATP-dependent uptake of sulfoglucuronides and glucuronides of the isoflavonoids was observed only in MRP2-expressing membrane vesicles. MRP2 plays a significant role in preventing the accumulation of phase II metabolites of isoflavonoids. The rs12762549 is associated with an interindividual difference in the plasma levels of MRP2 substrates, phase II metabolites of isoflavonoids, suggesting that this single nucleotide polymorphism is associated with variations in in-vivo MRP2 activity.

Hypertension: From Epidemiology to Therapeutics

P. Boli and R. Campbell discuss whether recommendations for the management (and control) of high blood pressure really result in improved cardiovascular (CV) outcomes. Adherence to the recommendations by the Canadian Hypertension Education Program did significantly improve all the aspects (awareness, treatment, and control) of hypertension, as well as mortality and hospitalization due to strokes, heart failure, and myocardial infarction. The authors suggest that application of similar recommendations for the management and control of hypertension in other regions of the world may be helpful. An interesting paper by C. Sierra reviewed that presence of cerebral white matter lesions (usually found in the aged population) were more severe and appeared early in patients with high blood pressure. There was an association between blood pressure parameters obtained by ambulatory blood pressure monitoring (ABPM) and presence of white matter lesions, suggesting that data obtained from ABPM may be helpful in identifying asymptomatic hypertensive patients with brain damage. R. Fagugli and C. Taglioni discuss that aldosteronism (hyperaldosteronism), which was thought to be rare (affecting 1% of the hypertensive population), occurs at a much higher incidence (5–20%) in patients with type 2 diabetics and resistant hypertension and is associated with a high incidence of cardiovascular (CV), cerebrovascular, and kidney complications. The variation in the estimates of prevalence may be due to methodology and definitions. M. Roy et al. determined that among African Americans with type 1 diabetes mellitus, without elevated blood pressure, 29% develop hypertension in the course of 6 years. The risk factors associated with the development of hypertension include age, duration of diabetes, family history of hypertension, higher baseline arterial pressure, overt proteinuria, presence of retinopathy or peripheral neuropathy, smoking, and psychological factors, such as perceived hostility. An interesting paper by M. Yamori et al. investigated the association of hypertension with periodontitis and/or tooth loss (apparently from periodontal disease) in a group of nonsmoking, nondrinking middle-aged African women. Their studies show that the severity of periodontal disease was significantly associated with increased systolic and diastolic blood pressure. In addition, low dietary intake of potassium and fiber was directly associated with higher blood pressure and periodontal inflammation. On the other hand, higher dietary intake of potassium, fruits, and vegetables decreased inflammation of the gums. The authors suggest that increased dietary intake of potassium, fruits, and vegetables may decrease the incidence of periodontitis. Q. Nguyen and coworkers analyzed cardiovascular risk factors in a large cross-sectional survey in Vietnam. The prevalence of the clustering of metabolic (such as in the metabolic syndrome) and behavioral risk factors was more prevalent in men than in women, and there was a 4-fold higher overall 10-year CV risk in men than in women. Targeting only a single risk factor would not decrease the overall risk. A pharmacological means of correcting endothelial dysfunction was proposed by M. Pokrovskiy et al., by the use of inhibitors of arginase (which catalyses the degradation of L-arginine and thereby reducing the production of nitric oxide), thus increasing the production of the vasodilating nitric oxide, thereby protecting the endothelium. In their studies in rats, R. Peroni and coworkers observed that phytoestrogens produced an estrogen receptor-dependent enhancement of anandamide-induced reduction of contractility (of mesenteric bed) caused by noradrenaline by modulation of calcitonin gene-related peptide. The in vivo suppression of adrenergic hyperactivity (which precedes the onset of hypertension) by anandamide (such as by oral administration of genistein or daidzein) was observed in female but not in male rats or ovariectomized female rats. Manuel Velsco Zafar Israili

Genistein and daidzein, in combination, protect cellular integrity during 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary carcinogenesis in Sprague-Dawley rats.

The status of glycoconjugates (protein bound hexose, hexosamine, sialic acid and fucose) in plasma or serum serve as potential biomarkers for assessing tumor progression and therapeutic interventions. Aim of the present study was to investigate the protective effect of two major soy isoflavones, genistein and daidzein, in combination on the status of glycoconjugates in plasma, erythrocyte membrane and mammary tissues during 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary carcinogenesis in female Sprague-Dawley rats. A single subcutaneous injection of DMBA (25 mg rat(-1)) in the mammary gland developed mammary carcinoma in female Sprague-Dawley rats. Elevated levels of plasma and mammary tissue glycoconjugates accompanied by reduction in erythrocyte membrane glycoconjugates were observed in rats bearing mammary tumors. Oral administration of genistein + daidzein (20 mg + 20 mg kg(-1) bw/day) to DMBA treated rats significantly (p< 0.05) brought back the status of glycoconjugates to near normal range. The present study thus demonstrated that genistein and daidzein in combination protected the structural integrity of the cell surface and membranes during DMBA-induced mammary carcinogenesis.

Chemopreventive Potential of Genistein and Daidzein in Combination during 7,12-dimethylbenz(a)anthracene (DMBA) Induced Mammary Carcinogenesis in Sprague-Dawley Rats

The chemopreventive potential of two major soy isoflavones, genistein and daidzein, in mammary carcinogenesis remains enigmatic. The aim of the present study was to investigate the chemopreventive potential of orally administered genistein, daidzein and genistein+daidzein in 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary carcinogenesis in Sprague-Dawley rats. The chemopreventive potential was assessed by monitoring the tumor incidence and tumor volume as well as by analyzing the status of biochemical markers (17beta-estradiol (E2)), enzymatic and non-enzymatic antioxidants and phase I and phase II detoxification enzymes) during DMBA-induced mammary carcinogenesis. A single subcutaneous injection of DMBA (25 mg rat(-1)) in the mammary gland developed mammary carcinoma in female Sprague-Dawley rats. Oral administration of genistein (20 mg kg(-1) b.wt.), daidzein (20 mg kg(-1) b.wt.) and genistein+daidzein (20 mg+20 mg kg(-1) b.wt.) to DMBA treated rats significantly prevented the tumor incidence and tumor volume as well as brought back the status of above said biochemical variables. Genistein and daidzein in combination have shown pronounced chemopreventive potential than either as genistein or daidzein alone. The present study revealed the chemopreventive potential of genistein+daidzein in combination during DMBA induced mammary carcinogenesis. The chemopreventive potential of genistein+daidzein is probably due to their antilipid peroxidative efficacy and modulatory effect on phase I and phase II detoxification cascade during DMBA induced mammary carcinogenesis.

Differential effect of pure isoflavones and soymilk on estrogen receptor activity in mice

Background Because of the complexity of estrogen receptor (ER) physiological activity, the interaction of pure isoflavones or soy-based diets on ER needs to be clearly demonstrated. Objectives To investigate the effects of the administration of isoflavones as a pure compound or as a component of diet on the ER transcriptional activity in adult mice. Methods Effects of acute (6 h) and chronic (21 days) oral administration of soy milk, pure genistein and a mix of genistein and daidzein was studied in living ERE-Luc mice. In this animal model, the synthesis of luciferase is under the state of ER transcriptional activity. Luciferase activity was measured in living mice by daily bioluminescence imaging sessions and in tissue extracts by enzymatic assay. Results Acute, oral administration of genistein or soymilk caused a significant increase of ER activity in liver. In a 20 day long treatment, soymilk was more potent than genistein in liver and appeared to extend its influence on ER transcriptional activity in other tissues, such as the digestive tract. A mixture of pure genistein and daidzein at the same concentration as in soymilk failed to induce significant changes during acute and chronic studies suggesting an important, uncharacterized role of the soymilk matrix. Consistent with this observation, synergistic effects of the matrix plus isoflavones were observed in MCF-7 cells stably transfected with the ERE-luc construct. Conclusions This study underlines the limitations of the analysis of single food components in the evaluation of their effects on estrogen receptor activity and advocates the necessity to use complex organisms for the full comprehension of the effects of compounds altering the endocrine balance.

Comparison of oral bioavailability of genistein and genistin in rats

Genistein (GT) is an isoflavone from Leguminosae and has received much attention as a phytoestrogen. Genistin is a glycoside form of GT (genistein-7- O-β- d-glucopyranoside, GT-glu) is mainly found in soy-derived foods. In this study, we examined the pharmacokinetic properties and bioavailability of GT in rats and compared with those of GT-glu. In order to characterize and compare the pharmacokinetics of GT and GT-glu, these compounds were administered intravenously and orally. The plasma concentration of GT was determined by HPLC after enzymatic hydrolysis. After oral administration of GT with various doses (4, 20, 40 mg/kg), the bioavailability of GT was 38.58, 24.34 and 30.75%, respectively. The T max, C max and AUC (0–∞) of GT after oral administration of GT (40 mg/kg), were 2 h, 4876.19 ng/ml, 31,269.66 ng h/ml, respectively. When smaller amount of GT was administered, the faster T max was observed. Oral administration of GT-glu resulted in longer T max, lower C max, and greater bioavailability than that of GT. The pharmacokinetic parameters of GT following oral administration of GT-glu (64 mg/kg as GT-glu, 40 mg/kg as GT) were obtained as follows: 8 h ( T max), 3763.96 ng/ml ( C max), 51,221.08 ng h/ml (AUC (0–∞)) and 48.66% (absolute bioavailability), respectively. These results indicate that the oral bioavailability of GT-glu is greater than that of GT.

Effect of genistein on the pharmacokinetics of paclitaxel administered orally or intravenously in rats

As many anticancer agents paclitaxel is a substrate for ATP-binding cassette (ABC) transporters such as P-glycoprotein-mediated efflux, and its metabolism in humans mainly catalyzed by CYP 3A4 and 2C8. Genistein, an isoflavonoid, is supposed to be an inhibitor of some ABC transporters, and its oxidative metobolism catalyzed by CYP 3A4 and 2C8. The purpose of this study was to investigate the effect of orally administered genistein on the pharmacokinetics of paclitaxel administered through oral and intravenous (i.v.) route in rats. A single dose of paclitaxel administered orally (30 mg/kg) or i.v. (3 mg/kg) alone or 30 min after oral administration of genistein (3.3 mg/kg or 10 mg/kg). The presence of 10 mg/kg genistein significantly ( p < 0.05) increased the area under the plasma concentration–time curve (AUC, 54.7% greater) of orally administered paclitaxel, which was due to the significantly ( p < 0.05) decreased total plasma clearance (CL/ F) of paclitaxel (35.2% lower). Genistein also increased the peak concentration ( C max) of paclitaxel significantly ( p < 0.05 by 3.3 mg/kg, 66.8% higher; p < 0.01 by 10 mg/kg, 91.8% higher). Consequently, the absolute bioavailability ( F) of paclitaxel in the presence of genistein was 0.020–0.025, which was elevated more than the control group (0.016); and the relative bioavailability (Fr) of orally administered paclitaxel was increased from 1.26- to 1.55-fold. Ten milligrams per kilogram genistein also significantly ( p < 0.05) increased the AUC (40.5% greater) and reduced the total clearance (CLt, 30% lower) of i.v. administered paclitaxel. The presence of genistein improved the systemic exposure of paclitaxel in this study. The pharmacokinetic interaction between them should be taken into consideration when paclitaxel is used with genistein or the dietary supplements full of genistein.

Synergistic effect of genistein and zinc on bone components in the femoral-metaphyseal tissues of female rats.

The effect of genistein and zinc on bone components in rats was investigated. Femoral-metaphyseal tissues obtained from female rats (4 weeks old) were cultured for 24 h in a medium containing either vehicle or genistein (10(-7)-10(-5) M) in the absence or presence of zinc sulfate (10(-6)-10(-4) M) in vitro. The presence of genistein (10(-6) and 10(-5) M) or zinc (10(-6) and 10(-5) M) caused a significant increase in alkaline phosphatase activity, deoxyribonucleic acid (DNA), and calcium content in the metaphyseal tissues. These increases were significantly enhanced by the combination of each compound. The synergistic effect on bone components was seen in the combination with genistein (10(-6) and 10(-5) M) plus zinc (10(-5) M). Such an effect was completely blocked by the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis. Moreover, the oral administration of genistein (100 and 300 micrograms/kg body weight) or zinc sulfate (1 and 5 mg Zn/kg) to rats for 3 days caused a significant elevation of alkaline phosphatase activity, DNA, and calcium content in the femoral-metaphyseal tissues. These increases were significantly enhanced by the combination of each compound. The synergistic effect was seen in the case of genistein (100 and 300 micrograms/kg) plus zinc (5 mg/kg). These results demonstrate that the anabolic effect of genistein on bone components is synergistically enhanced by zinc in vitro and in vivo. This study further supports the view that the combination of nutritional factors has a potent anabolic effect on bone metabolism.

Zinc Enhancement of Genistein’s Anabolic Effect on Bone Components in Elderly Female Rats

1. The effect of genistein on the bone components in the femoral-metaphyseal and diaphyseal tissues of elderly female rats was investigated. 2. The oral administration of genistein (100 and 200 μg/kg body weight) for 3 days to rats caused a significant increase in alkaline phosphatase activity, deoxyribonucleic acid (DNA) and calcium contents in the femoral-metaphyseal and diaphyseal tissues. A dose of 50 μg genistein/kg appreciably increased alkaline phosphatase activity and DNA content in the metaphyseal but not the diaphyseal tissues. 3. Alkaline phosphatase activity, DNA and calcium contents in the femoral-metaphyseal and diaphyseal tissues were significantly elevated by the oral administration of zinc sulfate (5.5 mg Zn/kg) for 3 days. The effect of zinc on increasing bone DNA and calcium contents was synergistically enhanced by the simultaneous administration of genistein (100 μg/kg). 4. The stimulatory effect of zinc sulfate (10 −5 M) or genistein (10 −5 M) on bone calcium content was also seen in a culture system using the femoral-metaphyseal and diaphyseal tissues in vitro. This effect was completely prevented by the presence of cycloheximide (10 −6 M). 5. The present findings suggest that genistein has an anabolic effect on bone components and that the effect is enhanced by zinc, owing to its stimulating effect on bone protein synthesis.

Urinary and biliary metabolites of genistein in rats.

Examination was made of the urinary and biliary excretion of the metabolites of genistein and genistein, the major components of Glycine and Sophora genus in rats. The urine of rats administered genistein orally contained eight metabolites. Three of these metabolites, genistein 4'-O-sulfate (M-1), genistein 7-O-beta-D-glucuronide (M-3), genistein 4'-O-sulfate 7-O-beta-D-glucuronide (M-6), were identified from spectroscopic and chemical data. The bile of rats administered genistein orally contained M-2, M-3 and M-6. M-6, a major biliary metabolite, was isolated and identified from spectroscopic and chemical data. The urine or bile of rats treated with genistein, the glycoside of genistein, contained M-1-M-8 or M-2, M-3, M-6 in the above metabolites. These findings suggest that genistein is absorbed as genistein after hydrolysis in the gastrointestinal tract. The total cumulative amounts of the two metabolites and genistein excreted in the urine during 48h, or of M-6 excreted in the bile during 36h following the oral administration of genistein, were approximately 5.7% or 16.0% of the doses administered, respectively. The result show that M-1, M-3 and M-6, having a free hydroxyl, glucuronide- or sulfate-conjugated hydroxyls at the C-7 or C-4' position, are excreted in the urine and bile as parts of the metabolites of genistein.