Lack of recovery from hepatic oxidative damage in rats treated with Nigerian bonny light crude oil

The use of Nigerian bonny light crude oil (BLCO) in the treatment of gastrointestinal disorders, burns, foot ulcers and reproductive capacity is a common practice in the southern part of Nigeria. Towards understanding the mechanism and the reversibility of hepatotoxicity induced by BLCO, adult male Wistar rats were orally administered with BLCO at 0, 50, 100 and 200?mg?kg(-1) for 21?days. One-half of the rats were sacrificed on day 22, whereas the remaining half stayed for an additional 21?days without treatment. Whereas the activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione S-transferase were significantly (p?相似文献   

4-Vinylcyclohexene diepoxide disrupts sperm characteristics,endocrine balance and redox status in testes and epididymis of rats

Objectives: Exposure to 4-vinylcyclohexene diepoxide (VCD) was reported to induce testicular germ cell toxicity in rodents. However, there is paucity of information on the precise biochemical and molecular mechanisms of VCD-induced male reproductive toxicity.

Methodology: This study investigated the influence of VCD on testicular and epidydimal functions following oral exposure of Wistar rats to VCD at 0, 100, 250 and 500?mg/kg for 28 consecutive days.

Results: Administration of VCD significantly decreased the body weight gain and organo-somatic indices of the testes and epididymis. When compared with the control, VCD significantly decreased superoxide dismutase and catalase activities in the testes whereas it significantly decreased superoxide dismutase activity but increased catalase activity in the epididymis. Moreover, while glutathione peroxidase activity and glutathione level remain unaffected, exposure of rats to VCD significantly increased glutathione S-transferase activity as well as hydrogen peroxide and malondialdehyde levels in testes and epididymis of the treated rats. The spermiogram of VCD-treated rats showed significant decrease in epididymal sperm count, sperm progressive motility, testicular sperm number and daily sperm production when compared with the control. Administration of VCD significantly decreased circulatory concentrations of follicle-stimulating hormone, luteinizing hormone and testosterone along with testicular and epididymal degeneration in the treated rats. Immunohistochemical analysis showed significantly increased cyclooxygenase-2, inducible nitric oxide synthase, caspase-9 and caspase-3 protein expressions in the testes of VCD-treated rats.

Conclusion: Exposure to VCD induces testicular and epidydimal dysfunctions via endocrine suppression, disruption of antioxidant enzymes activities, increase in biomarkers of oxidative stress, inflammation and apoptosis in rats.     

Diphenyl Diselenide Protects Against Mortality,Locomotor Deficits and Oxidative Stress in Drosophila melanogaster Model of Manganese-Induced Neurotoxicity

Several experimental and epidemiological reports have associated manganese exposure with induction of oxidative stress and locomotor dysfunctions. Diphenyl diselenide (DPDS) is widely reported to exhibit antioxidant, anti-inflammatory and neuroprotective effects in in vitro and in vivo studies via multiple biochemical mechanisms. The present study investigated the protective effect of DPDS on manganese-induced toxicity in Drosophila melanogaster. The flies were exposed, in a dietary regimen, to manganese alone (30 mmol per kg) or in combination with DPDS (10 and 20 µmol per kg) for 7 consecutive days. Exposure to manganese significantly (p < 0.05) increased flies mortality, whereas the survivors exhibited significant locomotor deficits with increased acetylcholinesterase (AChE) activity. However, dietary supplementation with DPDS caused a significant decrease in mortality, improvement in locomotor activity and restoration of AChE activity in manganese-exposed flies. Additionally, the significant decreases in the total thiol level, activities of catalase and glutathione-S-transferase were accompanied with significant increases in the generation of reactive oxygen and nitrogen species and thiobarbituric acid reactive substances in flies exposed to manganese alone. Dietary supplementation with DPDS significantly augmented the antioxidant status and prevented manganese-induced oxidative stress in the treated flies. Collectively, the present data highlight that DPDS may be a promising chemopreventive drug candidate against neurotoxicity resulting from acute manganese exposure.

     

Influence of kolaviron and vitamin E on ethylene glycol monoethyl ether‐induced haematotoxicity and renal apoptosis in rats

The present study investigated the protective effects of kolaviron, a biflavonoid from the seed of Garcinia kola, and vitamin E on ethylene glycol monoethyl ether (EGEE)‐induced haematotoxicity and renal apoptosis in male rats. EGEE was administered at a dose of 200 mg kg^?1 alone or simultaneously administered with kolaviron (100 and 200 mg kg^?1) and vitamin E (50 mg kg^?1) for 14 days. Results of haematological examination showed that white blood cells, platelets, neutrophils and mean corpuscular haemoglobin concentration were significantly lower, whereas lymphocytes were increased in EGEE‐exposed rats compared with those in the control. Administration of EGEE caused a significant decrease in the superoxide dismutase and catalase activities as well as in the glutathione level but significantly increased glutathione Stransferase activity and levels of hydrogen peroxide and lipid peroxidation in kidneys of rats compared with those in the control. Also, EGEE‐treated rats showed significant elevation in the serum urea and creatinine with marked increase in the frequency of terminal deoxynucleotidyl transferase‐mediated dUTP nick end labelling assay‐positive apoptotic cells in the tubular epithelial cells in comparison with the control. Co‐administration with kolaviron or vitamin E exhibited chemoprotective effects against EGEE‐mediated haematotoxicity, augmented renal antioxidant status and prevented the induction of renal apoptosis. Copyright © 2013 John Wiley & Sons, Ltd.     

Redox status of the testes and sperm of rats following exposure to 2,5-hexanedione

Objectives: Exposure to 2,5-hexanedione (2,5-HD) is well known to be associated with reproductive dysfunctions in both humans and animals. However, the role of oxidative stress in 2,5-HD-induced toxicity in testes and sperm has not yet been studied.

Methodology: The present study investigated the influence of 2,5-HD on antioxidant systems in the testes and epididymal sperm of rats following exposure to 0, 0.25, 0.5, and 1% 2,5-HD in drinking water for 21 consecutive days.

Results: Administration of 0.5% 2,5-HD significantly (P?<?0.05) decreased epididymis weight, whereas 1% 2,5-HD-treated rats showed significantly decreased body weight, testis, and epididymis weights compared with the control group. Exposure to 2,5-HD caused a significant dose-dependent increase in the activities of superoxide dismutase, catalase, and glutathione peroxidase in both testes and sperm compared with the control group. Moreover, 2,5-HD-exposed rats showed significant decrease in glutathione-S-transferase activity and glutathione level with concomitant significant elevation in the levels of hydrogen peroxide and malondialdehyde in both testes and sperm. Testicular and epididymal atrophy with significant, dose-dependent, decrease in epididymal sperm number, sperm motility, and viability were observed in 2,5-HD-treated rats.

Conclusion: 2,5-HD exposure impaired testicular function and sperm characteristics by disruption of the antioxidant systems and consequently, increased oxidative stress in the treated rats.     

Taurine Ameliorates Renal Oxidative Damage and Thyroid Dysfunction in Rats Chronically Exposed to Fluoride

Excessive exposure to fluoride poses several detrimental effects to human health particularly the kidney which is a major organ involved in its elimination from the body. The influence of taurine on fluoride-induced renal toxicity was investigated in a co-exposure paradigm for 45 days using five groups of eight rats each. Group I rats received normal drinking water alone, group II rats were exposed to sodium fluoride (NaF) in drinking water at 15 mg/L alone, group III received taurine alone at a dose of 200 mg/kg group IV rats were co-administered with NaF and taurine (100 mg/kg), while group V rats were co-administered with NaF and taurine (200 mg/kg). Administration of taurine significantly reversed the fluoride-mediated decrease in absolute weight and organo-somatic index of the kidney in the exposed rats. Taurine significantly prevented fluoride-induced elevation in plasma urea and creatinine levels in the exposed rats. Moreover, taurine restored fluoride-mediated decrease in the circulatory concentrations of triiodothyronine, thyroxine, and the ratio of triiodothyronine to thyroxine. Taurine ameliorated fluoride-mediated decrease in renal antioxidant status by significantly enhancing the antioxidant enzyme activities as well as glutathione level in the exposed rats. Additionally, taurine inhibited fluoride-induced renal oxidative damage by markedly decreasing the hydrogen peroxide and malondialdehyde levels as well as improved the kidney architecture in the treated rats. Collectively, taurine protected against fluoride-induced renal toxicity via enhancement of thyroid gland function, renal antioxidant status, and histology in rats.     

Ellagic acid mitigates rotenone-induced damage via modulating mitochondria function in Drosophila melanogaster

Constant, systematic exposure to rotenone has been utilized in animal models to induce Parkinsonism. Ellagic acid is a polyphenol with anti-inflammatory and antioxidative properties which is found in numerous natural fruits. Here, we investigated the therapeutic effects of ellagic acid in rotenone-induced toxicity in Drosophila melanogaster evaluating their antioxidant and mitoprotective properties. Adult flies were treated with rotenone and ellagic acid through their diet for 7 days, thereafter markers of neurotoxicity (acetylcholinesterase, monoamine oxidase, tyrosine hydroxylase), antioxidant and oxidative stress markers (hydrogen peroxide, nitric oxide, lipid peroxidation, protein carbonyl contents, catalase, total thiol, and nonprotein thiol) was measured. Mitochondrial respiration was also evaluated in the flies. Survival assay was carried out with both genders of the flies, and we observed a significant increase in the survival rate of flies exposed to both rotenone and ellagic acid when compared with the increased mortality rate in the groups exposed to rotenone alone. The impaired locomotion, altered redox status, and enzymes of neurotoxicity induced by rotenone were significantly ameliorated by ellagic acid to levels comparable to the control. In addition, rotenone-induced complex 1 inhibition and altered bioenergetic state were restored upon ellagic acid supplementation. These findings show the beneficial properties of ellagic acid against pesticides induced toxicity.     

Ethanol via Regulation of NF-κB/p53 Signaling Pathway Increases Manganese-Induced Inflammation and Apoptosis in Hypothalamus of Rats

Biological Trace Element Research - The diet is a major route of manganese (Mn) exposure for humans. Interestingly, several epidemiological data demonstrated an increase in the incidence of alcohol...