Effect of L-Ascorbic Acid on Nickel-Induced Alteration of Cardiovascular Pathophysiology in Wistar Rats.

Nickel, a widely used heavy metal is suspected as a cardiotoxic element. The aim of the present study was to assess the possible protective role of l-ascorbic acid on nickel-induced alterations of cardiovascular pathophysiology in male albino rats. Twenty-four albino rats (b.wt. 170-250 g) were randomized into four groups: control; l-ascorbic acid (50 mg/100 g b.wt., orally); NiSO4 (2.0 mg/100 g b.wt., i.p.); NiSO4 with l-ascorbic acid. Cardiovascular electrophysiology, serum and cardiac tissue malondialdehyde (MDA), nitric oxide (NO), ascorbic acid, serum α-tocopherol and serum vascular endothelial growth factor (VEGF) were evaluated. Histopathology of cardiac and aortic tissues was also assessed. NiSO4-treated rats showed a significant increase in heart rate, LF/HF ratio and blood pressure (SBP, DBP and MAP). A significant increase of serum MDA, NO and VEGF in NiSO4 treatment with a concomitant decrease of serum ascorbic acid and α-tocopherol as compared to their respective controls were also observed. Simultaneous supplementation of l-ascorbic acid with NiSO4 significantly decreased LF/HF ratio, BP and oxidative stress parameters, whereas ascorbic acid and α-tocopherol concentration was found to be increased. Histopathology of cardiac and aortic tissues showed nickel-induced focal myocardial hypertrophy and degeneration in cardiac tissue with focal aneurism in aortic tissues. Supplementation with l-ascorbic showed a protective action in both cardiac and aortic tissues. Results indicated the possible beneficial effect of l-ascorbic acid on nickel-induced alteration of the cardiovascular pathophysiology in experimental rats.

Sub-chronic indomethacin treatment and its effect on the male reproductive system of albino rats: possible protective role of black tea extract.

BACKGROUND: Indomethacin is commonly used as a nonsteroidal anti-inflammatory drug (NSAID) to treat inflammation, arthritis and joint pains. Unfortunately, it has a wide range of adverse effects on the physiological system, including gonads. This study aimed to assess possible beneficial effects of black tea extract (BTE) against indomethacin-induced alteration of gonadal hormone levels in male rats. METHODS: Adult male rats were divided into Group I (control), Group II (indomethacin, 5 mg/kg body weight [bwt.]; i.p., 21 days), Group III (BTE, 2.5 g tea leaf/dL of water, i.e. 2.5% of aqueous BTE, orally, 21 days) and Group IV (indomethacin+BTE, 21 days). Sperm count and motility, serum luteinising hormone (LH), follicle-stimulating hormone (FSH) and testosterone, along with histopathology of testes were studied. One-way ANOVA, followed by post-hoc t-test were conducted. RESULTS: Indomethacin-treated rats showed significant decrease in testicular weight, sperm count, sperm motility, serum gonadotropins and testosterone concentrations. Histopathology of the testes showed tortuous and distorted seminiferous tubules, marked thickening of the tubular basement membrane, reduced spermatogenesis process (>30%) and marked decrease in the number of interstitial cells of Leydig in indomethacin-treated rats. Interestingly, rats supplemented with BTE showed remarkable improvements in testicular weight gain, sperm count and motility, serum gonadotropins and testosterone concentrations, along with testicular histopathology. CONCLUSIONS: The results suggest that BTE might have potential ameliorative effects against sub-chronic indomethacin-induced alteration of gonadal hormone levels in male albino rats.

α-tocopherol supplementation prevents lead acetate and hypoxia-induced hepatic dysfunction.

OBJECTIVE: Lead (Pb) is a long-known poison of environment and industrial origin. Its prolonged exposure affects cellular material and alters cellular genetics and produces oxidative damages. In this study, we investigated the exposure of chronic sustained hypoxia or lead acetate alone or in combination with or without supplementation of α-tocopherol on hepatic oxidative and nitrosative stress in rats. MATERIALS AND METHODS: The rats weighing 165 ± 5 g were exposed to chronic sustained hypoxia (10% oxygen) or lead acetate (25 mg/kg of body weight, intraperitoneally) alone or in combination with or without supplementation of α-tocopherol (10 mg/100 g b.wt, intramuscularly). The body weight of all the rats was recorded on the day 1 of the treatment and the day of sacrifice. Serum lipid profile was estimated by using a biochemical analyzer. Oxidant and enzymatic antioxidants status was evaluated by using spectrophotometer. Serum levels of hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) were measured by using ELISA technique. Histopathological assessments of hepatic tissue were also done. RESULTS: Exposure of both lead and hypoxia showed decreased body weight, altered serum lipid profile, oxidant and enzymatic antioxidants status, serum HIF-1α and VEGF concentrations. Simultaneous α-tocopherol supplementation showed beneficial effects to all these alterations. Histopathological observations also showed hepatic degenerative changes after lead or hypoxia exposure either alone or in combination, but remarkable improvement has been noticed after α-tocopherol supplementation. CONCLUSION: Supplementation of α-tocopherol is beneficial to counter both lead acetate and hypoxia induced hepatic cytotoxicities possibly by reducing oxidative and nitrosative stress.

Ameliorating effect of black tea extract on cadmium chloride-induced alteration of serum lipid profile and liver histopathology in rats.

Cadmium is one among the most environmental pollutants that affects many organs like kidney, liver and testis. The present study was aimed to assess the simultaneous effects of black tea extracts (BTE) on cadmium chloride induced alterations in lipid profile and liver histology. Adult rats were divided into four groups (n=6/group), group I (normal saline), group II (CdCl2, 1.0 mg/kg, b.wt; i.p), group III (black tea extract, 2.5 gm tea leaf/dl of water that is 2.5% of aqueous BTE) and group IV (cadmium chloride + BTE). Cadmium chloride intoxicated rats showed significant increase in serum total cholesterol, triglycerides, and low density lipoprotein-cholesterol and there is a significant decrease in the serum high density lipoprotein-cholesterol. In the liver, cadmium chloride showed changes in normal architecture, swollen hepatocytes, kupffer cells hyperplasia, dilation and congestion of central vein. Oral administration of black tea extracts with cadmium chloride significantly improves lipid profile and liver architecture as compared to the cadmium chloride group. The results indicate that BTE is beneficial in preventing cadmium-induced lipid alterations and hepatocellular damage.

α-Tocopherol ameliorates nickel induced testicular oxidative and nitrosative stress in albino rats.

BACKGROUND: Heavy metals generate free radicals and induce oxidative and nitrosative stress with depletion of antioxidants. In this study, we have evaluated the beneficial effects of α-tocopherol against nickel sulfate exposed testicular dysfunction. METHODS: We studied the effect of supplementation of α-tocopherol (10 mg/100 g body weight, i.m.) on nickel sulfate (2.0 mg/100 g body weight, i.p.) induced testicular oxidative and nitrosative stress in Wister strain male albino rats. Serum and testicular nitric oxide, L-ascorbic acid and serum α-tocopherol concentrations were evaluated. We also evaluated sperm count, motility and histopathology of testes. RESULTS: Nickel treated rats showed significantly decreased body weight, testicular somatic index, sperm count, sperm motility, serum and testicular L-ascorbic acid concentration and serum α-tocopherol level as compared to their controls. However, simultaneous treatment with nickel sulfate and α-tocopherol produced a remarkable improvement of all the above parameters when compared with treatment with nickel alone. Nickel treated rats also had significantly increased serum and testicular nitric oxide concentrations as compared to their controls. However, simultaneous treatment with nickel sulfate and α-tocopherol significantly decreased nitric oxide concentrations in both serum and testes, respectively, as compared to nickel treatment alone. Histopathology of the testes revealed tortuous seminiferous tubules, loss of spermatogenesis process (>75%), congestion and necrosis in nickel sulfate treated rats, whereas rats simultaneously treated with nickel sulfate and α-tocopherol had almost normal seminiferous tubules and near normal spermatogenesis as compared to nickel alone treated rats. CONCLUSIONS: Nickel sulfate treatment causes testicular oxidative and nitrosative stress in albino rats, but simultaneous supplementation of α-tocopherol was found to be beneficial in combating against such stresses.

Effect of garlic (Allium sativum) on hematology and erythrocyte antioxidant defense system of albino rats exposed to heavy metals (nickel II & chromium VI).

Heavy metals are stable environmental contaminants, causing various alterations in target tissues. Garlic has some beneficial effect in preventing heavy metal induced various alteration. The objective was to investigate the possible protective role of fresh aqueous homogenate of garlic on hematology, erythrocyte antioxidant defense system in male albino rats treated with NiSO4 and K2Cr2O7. Rats were divided into six groups. Group I was untreated control. Group II was given aqueous homogenate of garlic (orally). Group III was administered with nickel sulfate (i.p). Group IV was given NiSO4 and garlic simultaneously. Group V was administered with K2Cr2O7 (i.p). Group VI were treated simultaneously with K2Cr2O7 and garlic. RBC, WBC, platelet count, PCV%, hemoglobin concentration decreased significantly and clotting time increased significantly after nickel treatment. After chromium treatment all the values decreased except clotting time. Increased malondialdehyde and glutathione level after nickel and chromium treatment was observed. Also erythrocyte superoxide dismutase, glutathione peroxidase and catalase activities significantly increased after nickel and chromium treatment. Simultaneous garlic supplementation exhibited protective role to combat nickel toxicity, whereas no such beneficial effects were observed for chromium (VI). Garlic may partially prevent nickel and chromium induced alteration but such ameliorated effects as an antioxidant is only restricted on nickel induced alteration.