No abstract

No abstract

We investigated the regulation of antioxidant system under acetaminophen (AAP) toxicity. Twelve male New Zealand rabbits were divided into two groups with the following treatments: Group 1 animals were intraperitoneally injected with single saline (control). Group 2 animals were treated with intraperitoneal injection of AAP at a dose of 250 mg/kg body weight. Four hours following the treatments, blood samples were collected and the rabbits were sacrificed to collect liver samples. Hepatocellular damage was evaluated by aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels as well as histopathological examinations and immunohistochemical analysis. Tissue-reduced glutathione (GSH), nitric oxide (NO(.)), and malondialdehyde (MDA) levels were also measured. mRNA expression levels of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) were measured by semi-quantitative RT-PCR. It was found that liver GSH was reduced significantly in AAP-treated rabbits (P < 0.05), while MDA and NO(.) levels were increased when they were compared to control (P < 0.05). Blood AST and ALT levels were also increased following AAP treatment (P < 0.05). Hepatocellular degeneration and severe necrosis were detected in histopathological examinations. Increased immunostaining was observed for inducible nitric oxide synthase (iNOS) and nitrotyrosine in the liver. There were no changes in mRNA expression levels of SOD, CAT, and GSH-Px after AAP treatment compared to control group. These results suggest that the expression of these enzymes, which are involved in the antioxidant system, may not be altered after AAP toxicity, although classical toxic changes such as depletion of GSH, hepatocellular necrosis, and increased immunostaining for iNOS and nitrotyrosine were detected.

The aim of this study was to evaluate effects of dietary zinc and L-arginine supplementation on blood total antioxidant capacity (TAC), malondialdehyde (MDA), nitric oxide (NO), some blood chemistry parameters, and egg weights of laying quails. Three groups of Japanese quails were fed with a diet containing L-arginine (5 mg/kg), zinc (60 mg/kg), and normal basal diet (control) for 30 days. TAC, lipid peroxidation, and biochemical analysis were performed in the blood of animals. L-Arginine and zinc supplementation improved TAC and reduced MDA concentrations compared to the control (P<0.05). In comparison to the control, blood NO concentrations were increased by Larginine (P<0.01) and zinc treatment (P<0.05). Both zinc (P<0.001) and L-arginine (P< 0.01) supplementation significantly increased egg weight in laying quails. Some of the blood chemistry parameters were also altered by the treatment of L-arginine and zinc supplementation. No difference was found in blood albumin and creatinine levels among the groups. Blood glucose (P=0.833) and total protein (P=0.264) levels in control and Larginine-treated groups were found to be similar. Glucose and total protein levels were decreased in zinc-supplemented animals compared to the control and L-arginine groups (P< 0.05). No difference was found in triglyceride levels between control and zinc-applied groups (P=0.197). However, L-arginine treatment reduced the blood triglyceride levels compared to the control (P<0.05). In conclusion, L-arginine and zinc supplementation could be beneficial and effective for decreasing oxidative stress, boosting antioxidant capacity, and improving egg weight in the blood of the animals.

No abstract