The effect of bisphenol A on testicular steroidogenesis and its amelioration by quercetin: an in vivo and in silico approach.

Bisphenol A (BPA), a phenyl ring containing synthetic xenoestrogen, is widely used in the manufacture of polycarbonate plastics, epoxy resins and as a non-polymer additive to other plastics. Food is considered as the main source of exposure to BPA as it leaches out from food containers as well as surface coatings. It causes toxicity in the liver, kidney, brain, and other organs by initiating the process of lipid peroxidation. The present investigation was an attempt to evaluate the effect of BPA on steroidogenesis and its amelioration by quercetin. Inbred Swiss strain male albino mice were orally administered with 80, 120 and 240 mg per kg body weight per day of BPA for 45 days. The results revealed that BPA causes significant (p < 0.05) and dose-dependent changes in the body weight and biochemical parameters like protein, cholesterol and lipid contents as well as activities of 3ß-and 17ß-hydroxysteroid dehydrogenases in the testis of mice. It was also found to significantly reduce the testosterone level in serum. Oral administration of quercetin (30, 60 and 90 mg per kg body weight per day) along with a high dose of BPA (240 mg per kg body weight per day) for 45 days caused significant amelioration in the body weight and steroidogenesis as compared to the BPA alone treated group. The effect was dose-dependent. This amelioration in BPA-induced toxicity might be due to the antioxidative properties of quercetin. The reduction in the function of enzymes was confirmed by in silico bindings. BPA and quercetin show competitive binding with steroidogenic enzymes as well as binding with each other. This could be a possible mechanism to reduce the toxic effect of BPA which has been supported by molecular dynamics simulations for molecular level recognition with structural insights.

Green tea potentially ameliorates bisphenol a-induced oxidative stress: an in vitro and in silico study.

The present investigation was an attempt to elucidate oxidative stress induced by bisphenol A on erythrocytes and its amelioration by green tea extract. For this, venous blood samples from healthy human adults were collected in EDTA vials and used for preparation of erythrocytes suspension. When erythrocyte suspensions were treated with different concentrations of BPA/H2O2, a dose-dependent increase in hemolysis occurred. Similarly, when erythrocytes suspensions were treated with either different concentrations of H2O2 (0.05-0.25 mM) along with BPA (50 µg/mL) or 0.05 mM H2O2 along with different concentrations of BPA (50-250 µg/mL), dose-dependent significant increase in hemolysis occurred. The effect of BPA and H2O2 was found to be additive. For the confirmation, binding capacity of bisphenol A with erythrocyte proteins (hemoglobin, catalase, and glutathione peroxidase) was inspected using molecular docking tool, which showed presence of various hydrogen bonds of BPA with the proteins. The present data clearly indicates that BPA causes oxidative stress in a similar way as H2O2 . Concurrent addition of different concentrations (10-50 µg/mL) of green tea extract to reaction mixture containing high dose of bisphenol A (250 µg/mL) caused concentration-dependent amelioration in bisphenol A-induced hemolysis. The effect was significant (P < 0.05). It is concluded that BPA-induced oxidative stress could be significantly mitigated by green tea extract.

Antioxidative mechanism involved in the preventive efficacy of Bergenia ciliata rhizomes against experimental nephrolithiasis in rats.

CONTEXT: Bergenia ciliata Haw. (Saxifragaceae) is widely used in traditional medicines for renal disorders including kidney stones, inflammation and also well known for its antioxidant activity. Use of traditional herbs proved to be an important strategy for the management of kidney stones by modulating the oxidative stress imposed by calcium oxalate nephrolithiasis. OBJECTIVES: To evaluate the antinephrolithiatic and antioxidative activity of B. ciliata rhizomes as a preventive agent on ethylene glycol (EG)-induced nephrolithiasis. MATERIALS AND METHODS: The hydro-methanol extract (30:70, v/v) of B. ciliata rhizomes was orally administrated simultaneously at a dose of 150 and 300 mg/kg body weight/day, to adult female Wistar rats for 28 d along with EG (0.75%, v/v) in drinking water. The results were compared to a parallel study conducted with marketed polyherbal drug cystone under identical dosage conditions. The biochemical parameters were measured in urine, serum and kidney followed by histochemistry. A validated HPLC method was used for standardization using gallic acid as a marker. RESULTS: EG caused a significant increase in calcium, oxalate and phosphate levels in urine and kidney and concurrent decrease in calcium, sodium and magnesium in serum (p<0.001). EG also caused an increase in lipid peroxidation and a decrease in activities of antioxidative enzymes in kidney. Co-treatment with B. ciliata rhizomes extract caused restoration of all these parameters (p<0.001). Histochemical studies showed reduced calcifications with extract treatment. CONCLUSION: B. ciliata has a significant prophylactic effect in preventing the nephrolithiasis, which might be mediated through antioxidant activity of these active compounds.

Antioxidative and cytoprotective effects of andrographolide against CCl4-induced hepatotoxicity in HepG2 cells.

This article describes antioxidative and cytoprotective property of andrographolide, a major active component of the plant Andrographis paniculata (A. paniculata). High yields (2.7%) of andrographolide was isolated from the aerial parts of this plant via silica column chromatography. The purity of the compound was determined by high-performance thin-layer chromatography (HPTLC) and reversed phase high-performance liquid chromatography (HPLC) analysis. The structure was elucidated using techniques such as UV-visible spectrophotometry, elemental analysis, Fourier transform infrared (FT-IR), (1)H nuclear magnetic resonance ((1)H NMR), (13)C nuclear magnetic resonance ((13)C NMR) and mass spectral analysis and the data obtained were comparable with reported results. It was observed that andrographolide exhibited significant antioxidative property (IC50 = 3.2 µg/ml) by its ability to scavenge a stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) as compared to known antioxidants like ascorbic acid, butylated hydroxy toluene (BHT) and the plant extract. The cytoprotective role of andrographolide against carbon tetrachloride (CCl4) toxicity in human hepatoma HepG2 cell line was assessed using trypan blue exclusion test, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, by estimation of various leakage enzymes and by measuring the glutathione levels. The recovery obtained for andrographolide treatment in the presence of CCl4 was two-fold compared to A. paniculata extract for all other related biochemical parameters investigated. The results of the study indicate that andrographolide is a potent inhibitor of CCl4-mediated lipid peroxidation.

Molecular alterations in oral carcinogenesis: significant risk predictors in malignant transformation and tumor progression.

In this study an attempt was made to establish the significance of a battery of molecular alterations and thereby identify risk predictors in oral carcinogenesis. For this purpose, EGFR, Stat3, H-ras, c-myc, p53, cyclin D1, p16, Rb, Ki-67 and Bcl-2 were localized immunohistochemically in normal mucosa (n=12), hyperplasia (n=35), dysplasia (n=25), early stage carcinoma (n=65) and advanced stage carcinoma (n=70). Deregulation occurred at an early stage and the number of alterations increased with disease progression. Using multivariate logistic regression analysis, the significant risk predictor for hyperplasia from normal mucosa was Ki-67 (OR=5.75, p=0.021); the significant risk predictors for dysplasia from hyperplasia were EGFR (OR=12.96, p=0.002), Stat3 (OR=17.16, p=0.0001), p16 (OR=5.50, p=0.039) and c-myc (OR=5.99, p=0.052); the significant risk predictors for early stage carcinoma from dysplasia were p53 (OR=6.63, p=0.0001) and Rb (OR=3.81, p=0.056); and the significant risk predictors for further progression were EGFR (OR=5.50, p=0.0001), Stat3 (OR=4.49, p=0.0001), H-ras (OR=4.05, p=0.001) and c-myc (OR=2.99, p=0.015). Cyclin D1 holds a key position linking upstream signaling pathways to cell cycle regulation. Gene products of the mitogenic signaling pathway play an equally significant role as cell cycle regulatory proteins in the hyperplasia-dysplasia-early-advanced-carcinoma sequence and together may provide a reference panel of markers for use in defining premalignant lesions and predicting the risk of malignant transformation and tumor progression.

Toxicological effects of Carica papaya seed extract on spermatozoa of mice.

Investigations were carried out on epididymal spermatozoa of male mice to study the effects of high dosages (100, 200 and 300 mg kg(-1) bwt) of aqueous Carica papaya seed extract. The results revealed a significant dosedependent suppression of cauda epididymal sperm motility coinciding with a decrease in sperm count and viability. When tested 45 days after the withdrawal of treatment, complete normalcy was restored, proving that the induced effects were transient.

Stat3 expression in oral squamous cell carcinoma: association with clinicopathological parameters and survival.

The present study sought to explore the occurrence of signal transducer and activator of transcription 3 (Stat3) in patients with oral squamous cell carcinoma (n=135) and its potential relationship with clinicopathological parameters and survival. Stat3 expression was studied by immunohistochemistry. Cytoplasmic or nuclear localization of Stat3 was observed in 62% of patients, whereas only nuclear Stat3 expression was found in 44%. Stat3 positivity in early-stage patients was 45% compared to 79% in advanced-stage patients. However, early-stage Stat3-positive patients showed a gradual increase in staining intensity, with intense staining seen in 52% of the tumors compared to 18% in Stat3-positive advanced-stage patients, where a gradual decrease in intensity expression was observed (p=0.001). Stat3 showed a significant positive correlation with disease stage (p=0.001), nodal status (p=0.033) and tumor size (p=0.001). Multivariate survival analysis using the Cox proportional hazard regression model showed that nuclear Stat3 was a significant independent prognosticator for both relapse-free survival (p=0.014) and overall survival (p=0.042) in early-stage patients. Our results indicated that Stat3 activation is an early event in oral squamous cell carcinoma and represents a potential risk factor for poor prognosis in early-stage patients.

Ameliorative effects of black tea extract on aflatoxin-induced lipid peroxidation in the liver of mice.

We have evaluated the ameliorative effect of black tea extract on aflatoxin-induced lipid peroxidation in the liver of mice. Adult male albino mice were orally administered with 25 and 50 microg of aflatoxin in 0.2 ml olive oil/animal/day for 30 days. Results revealed dose-dependent and significantly (p<0.05) higher lipid peroxidation in the liver of aflatoxin-treated mice than that of vehicle control. As compared with vehicle control, the levels of non-enzymatic antioxidants such as glutathione and ascorbic acid, as well as the enzymatic antioxidants such as superoxide dismutase, glutathione peroxidase and catalase were significantly (p<0.05) lowered in the liver of aflatoxin-treated mice. Oral administration of two percent aqueous black tea extract along with aflatoxin for 30 days (groups 6 and 7) caused significant (p<0.05) amelioration in aflatoxin-induced lipid peroxidation by increasing significantly (p<0.05) the activities of enzymatic (superoxide dismutase, glutathione peroxidase, catalase) and contents of non-enzymatic (glutathione and ascorbic acid) antioxidants in the liver of mice as compared with those given aflatoxin alone (groups 4 and 5). Thus, oral administration of black tea along with aflatoxin significantly (p<0.05) ameliorates aflatoxin-induced lipid peroxidation in the liver of mice.

Arsenic toxicity in mice and its possible amelioration.

Oral administration of arsenic trioxide (3 and 6 mg/kg body weight/d) for 30 d caused, as compared with vehicle control, dose-dependent significant reductions in body weight, absolute weight, protein, glycogen, as well as, total, dehydro and reduced ascorbic acid contents both in the liver and kidney of arsenic-treated mice. Succinic dehydrogenase (SDH) and phosphorylase only in the liver activities were significantly reduced in a dose-dependent manner. Acid phosphatase activity was significantly decreased in the liver of low dose arsenic-treated animals; however, significant rise in its activity was observed in high dose group. As compared with vehicle control, treatment also caused significant dose-dependent reductions in SDH, alkaline phosphatase and acid phosphatase activities in the kidney of mice. Vitamin E cotreatment as well as, 30 d withdrawal of arsenic trioxide treatment with or without vitamin E caused significant amelioration in arsenic-induced toxicity in mice. Administration of vitamin E during withdrawal of treatment also caused significant amelioration as compared from only withdrawal of the treatment. It is concluded that vitamin E ameliorates arsenic-induced toxicities in the liver and kidney of mice.

Sodium fluoride-induced hypoproteinemia and hypoglycemia in parental and F(1)-generation rats and amelioration by vitamins.

Oral administration of sodium fluoride (NaF; 40 mg/kg body weight) daily from day 6 of gestation to day 21 of lactation caused, compared with the distilled water control (group 2), significant reductions in body weight and feed consumption as well as concentration of glucose and protein in the serum of P- and F(1)-generation rats; however, sodium and potassium concentrations in the serum were significantly higher than those of the vehicle control (group 2). Administration of either vitamins C (50 mg/kg body weight/day), D (2 ng/0.2 ml olive oil/animal/day) or a combination of vitamins C+D+E along with NaF caused significant amelioration in body weight and feed consumption, as well as glucose, protein, sodium and potassium concentrations in the serum of P- and F(1)-generation rats compared with the NaF-only treated group. Withdrawal of NaF treatment during lactation caused significant amelioration in feed consumption (days 15-21 only), sodium, potassium, glucose and protein concentrations in the serum of both P- and F(1)-generation rats. Co- treatment with vitamin E (2 mg/0.2 ml olive oil/animal/day) caused significant amelioration in body weight (days 15 and 20 of gestation only), sodium, potassium, glucose (only in P-generation females) and protein (only in P-generation female) concentrations in the serum of rats than in NaF-treated rats alone. It is concluded that co-treatment with vitamins C, D and C+D+E were found more effective in ameliorating NaF-induced effects than vitamin E and withdrawal of NaF treatment during lactation.

Effect of aflatoxins on testicular steroidogenesis and amelioration by vitamin E.

The potential of aflatoxin to affect testicular steroidogenesis and its amelioration by vitamin E was assessed in the present investigation. Oral administration of aflatoxin (25 and 50 microg/animal/day) for 45 days to adult mice caused, as compared with control, a dose-dependent significant rise in cholesterol content. However, the activities of 3beta- and 17beta-hydroxysteroid dehydrogenases and serum testosterone levels were significantly reduced in aflatoxin-treated mice as compared with the controls. Pretreatment with vitamin E (2 mg/animal/day, orally) significantly ameliorated aflatoxin-induced changes as compared with aflatoxin treatment alone. The present investigation clearly indicates that vitamin E ameliorates aflatoxin-induced changes in steroidogenesis.

Hypocalcaemia in parental and F1 generation rats treated with sodium fluoride.

The potential of sodium fluoride (NaF) to affect serum cations was assessed in the parent (P) and F1 generation rats. The sperm-positive pregnant experimental female rats received 40 mg NaF/kg body weight from day 6 of gestation either up to 21 days of lactation or only up to gestation followed by withdrawal of the treatment during lactation. On day 21 of lactation, blood samples were collected from P and F1 generation rats, allowed to clot and centrifuged at 1000 g for 10 min to obtain serum for analysis of various cations. Statistically significant increases in the concentrations of sodium and potassium in the serum of P and F1 generation rats were observed in the NaF-treated group; however, calcium and phosphorus concentrations were significantly lower than their vehicle control. Withdrawal of NaF treatment during lactation caused significant recovery in sodium, potassium and phosphorus concentrations in P and F1 generation rats as compared with NaF-treated animals. Although statistically significant recovery was not observed, the calcium concentration in P and F1 generation rats was comparatively higher on withdrawal of NaF treatment than in the NaF-treated group. It is concluded that the exposure of 40 mg NaF/kg body weight in pregnant female rats caused significant alterations in cationic concentration which recovered significantly (except calcium) on withdrawal of the treatment.

Effect of papaya seed extract on contractile response of cauda epididymal tubules.

AIM: To evaluate the administration of Carica papaya seed extract on the contractility of cauda epididymal tubules in male rats. METHODS: Adult male albino rats were administered intramuscularly papaya seed extract at a dose of 0.5 mg/kg/day for 7 days. Animals were killed, cauda epididymal tubules of 5 cm length were isolated and the contractile response to different concentrations of adrenalin (1-500 microg/25mL) was examined. In another group of animals, the contractile response was assayed 3 months after withdrawal of the treatment. RESULTS: Papaya seed extract brought about a significant decrease in the contractile response of epididymal tubules as compared with the control. After three months of papaya withdrawal, a nearly normal pattern of contraction was regained. CONCLUSION: Papaya seed treatment reversibly reduces the contractile response of cauda epididymal tubules.

Vitamin E ameliorates aflatoxin-induced biochemical changes in the testis of mice.

AIM: To assess the effect of aflatoxin on biochemical changes in the testis of mice and the possibility of amelioration by vitamin E treatment. METHODS: Adult male albino mice were orally administered with 25 or 50 microg of aflatoxin/animal/day (750 or 1500 microg/kg body weight) for 45 days. The testis was isolated and processed for biochemical analysis. RESULTS: There was a significant, dose-dependent reduction in DNA, RNA, protein, sialic acid contents and the activities of succinic dehydrogenase, adenosine triphosphatase and alkaline phosphatase in the testis of aflatoxin-treated mice as compared to the vehicle control. However, the acid phosphatase activity was significantly increased in the aflatoxin-treated mice. Vitamin E (2 mg/animal/day) treatment significantly ameliorated the aflatoxin-induced changes, except the acid and alkaline phosphatase activities in the high dose group. CONCLUSION: Vitamin E treatment ameliorates the aflatoxin-induced changes in the testis of mice.

Sperm quiescence in cauda epididymis: a mini-review.

The concentration of sodium chloride is of prime importance in the initiation and reversal of sperm quiescence in the cauda epididymis. Other factors such as inorganic and organic constituents of the luminal fluid are of secondary importance and might assist in inducing sperm quiescence.

Ameliorative effect of vitamin E on aflatoxin-induced lipid peroxidation in the testis of mice.

AIM: To evaluate the ameliorative effect of vitamin E on aflatoxin-induced lipid peroxidation in the testis. METHODS: Adult male albino mice were orally administered 25 or 50 microg of aflatoxin in 0.2 mL olive oil per d for 45 d. The testis was isolated, blotted free of blood and processed for biochemical analysis. RESULTS: There was a dose-dependent significantly higher lipid peroxidation in the testis of aflatoxin treated mice than in the controls. The levels of non-enzymatic antioxidants such as glutathione, total and reduced ascorbic acid, as well as the activities of enzymatic antioxidants, such as superoxide dismutase, glutathione peroxidase and catalase were significantly lower in the testis of aflatoxin treated mice. Vitamin E (2 mg/d per animal; orally) pretreatment significantly ameliorates the aflatoxin-induced lipid peroxidation which could be due to higher enzymatic and non-enzymatic antioxidants in the testis of mice as compared with those given aflatoxin alone. CONCLUSION: Vitamin E pretreatment significantly ameliorates aflatoxin-induced lipid peroxidation in the testis of mice.

Effect of papaya seed extract on microenvironment of cauda epididymis.

AIM: To evaluate the effect of aqueous Carica papaya seed extract on microenvironment of cauda epididymis. METHODS: Adult male albino rats were intramuscularly administered with 0 (control) or 0.5 mg papaya seed extract/kg body weight for 7 days. Cauda epididymal tubular content was collected by micropuncture technique; epididymal luminal fluid and sperm pellets were separately analyzed. RESULTS: The results revealed that the extract treatment caused significant reduction, as compared with control, in total protein and sialic acid contents in both epididymal fluid and sperm pellet. As compared with control, significantly lowered acid phosphatase activity was recorded in sperm pellet but was higher in epididymal fluid after the treatment. The extract treatment also caused significant reduction in level of inorganic phosphorus in the epididymal fluid. CONCLUSION: It is concluded that the aqueous papaya seed extract alters cauda epididymal microenvironment.

Vitamin D ameliorates fluoride-induced embryotoxicity in pregnant rats.

We have evaluated the ameliorative effect of vitamin D on fluoride-induced embryotoxicity in pregnant rats. Oral administration of sodium fluoride (NaF; 40 mg/kg body weight) from days 6 to 19 of gestation caused, as compared with control, significantly lowered body weight, feed consumption, absolute uterine weight and number of implantations. As compared with the control, higher incidence of skeletal (presence of wavy ribs, 14th rib, dumbbell-shaped 5th sternebrae, incomplete ossification of skull) and visceral (subcutaneous haemorrhage) abnormalities was recorded in the foetuses of fluoride-treated pregnant rat. Vitamin D (2 ng/0.2 ml olive oil/animal/day po) treatment significantly ameliorated the fluoride-induced reductions in body weight, feed consumption and absolute uterine weight. As compared with fluoride-treated alone, the total percentage of skeletal and visceral abnormalities observed in foetuses was significantly lowered in fluoride plus vitamin D-treated animals. These findings suggest that vitamin D treatment significantly reduced the severity and incidence of fluoride-induced embryotoxicity. The ameliorative effect of vitamin D against skeletal and visceral abnormalities could be due to stimulation of intestinal absorption of calcium and phosphate, thus raising the plasma calcium and phosphate concentrations.

Amelioration of cytotoxic effects of aflatoxin by vitamin A: an in vitro study on erythrocytes.

We have evaluated the ameliorative role of vitamin A on aflatoxin-induced cytotoxicity in vitro. Aflatoxin (1.95 microM)-induced hemolysis was found to be significantly reduced on addition of vitamin A (125--1250 IU/ml) in incubation medium. The decrease in hemolysis was almost dose dependent. The kinetics of reduction of AFB(1) to B(2) and AFG(1) to G(2) by vitamin A has been investigated in dilute aqueous solution at 37 degrees C. The rate of the reduction was found to be first order with respect to the concentration of vitamin A and aflatoxin concentration.

Vitamin C ameliorates fluoride-induced embryotoxicity in pregnant rats.

Oral administration of sodium fluoride (40 mg/kg body weight) from day 6 to 19 of gestation caused, as compared to control, significant reductions in body weight, feed consumption, absolute uterine weight and number of implantations. Significantly higher incidence of skeletal (wavy ribs, 14th rib, <6 sternal centre, dumbell-shaped second and fifth sternebrae, incomplete ossification of skull and thickening of tibia) and visceral (subcutaneous haemorrhage) abnormalities were also observed in NaF-treated dams than that of control. Oral administration of vitamin C (50 mg/kg body weight) and vitamin E (2 mg/0.2 ml olive oil/animal/day) from day 6 to 19 of gestation along with NaF significantly ameliorates NaF-induced reductions in body weight, feed consumption, absolute uterine weight (only with vitamin E treatment) and number of implantations. As compared with NaF-treated alone, the total percentage of skeletal and visceral abnormalities were significantly lowered in fluoride plus vitamin C-treated animals. Vitamin E was less effective. These findings suggest that vitamin C significantly reduced the severity and incidence of fluoride-induced embryotoxicity in rats.