The aim of the study was to investigate the ameliorative properties of ascorbic acid against the subchronic effect of co-exposure of fluoride (F) and chlorpyrifos (CPF) on oxidative damage markers such as lipid peroxidation (MDA) and antioxidant defense system in the liver of adult Wistar rats. The animal groups were provided with either vehicle or ascorbic acid (60 mg/kg, b.w.) or NOAEL dose of fluoride (1 ppm) or CPF (1 mg/kg, b.w.) or ten times of such doses orally alone and in combination or pre-treated with ascorbic acid along with co-exposure of F and CPF every consecutive day for 28 days. Hepatic damage marker analysis in blood revealed that aspartate and alanine aminotransferases, alkaline phosphatase, and lactate dehydrogenase were significantly (P < 0.05) increased with single or combined exposure of F or CPF at either dose levels. Significant increased oxidative damage of hepatocytes as indicated by increased MDA levels with decrease in tissue ascorbate and free radical scavenging enzymes like catalase, superoxide dismutase, and glutathione peroxidase was observed in groups treated with either F or CPF as well as in combinedly treated animals as compared to control animals. Supplementation of ascorbic acid restored the hepatic specific marker enzymes in blood following co-exposure of F and CPF at lower doses which were otherwise increased in the F and CPF co-exposed rats. The results show that ascorbic acid supplementation with F and CPF prevents or diminishes the hepatic damage in rats co-exposed to toxicants and may act as a putative protective agent against toxicant-induced liver tissue injury.

The present study was aimed to determine the total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) of plasma and renal tissue in cisplatin (cDDP) induced nephrotoxic rats and its protection by treatments with floral extracts of Calendula officinalis Linn. Treatment with cDDP elevated (p < 0.05) the levels of blood urea nitrogen, creatinine (CR), TOS, OSI and malondialdehyde (MDA) but lowered (p < 0.05) total plasma proteins, TAS, total thiols (TTH), blood glutathione (GSH) and antioxidant enzymes compared to the control group. Pre- and post-treatments of ethanolic floral extract of C. officinalis along with cDDP restored (p > 0.05) CR, albumin, TOS, GSH and activities of antioxidant enzymes in blood and renal tissue. Ethanolic extract treatments reduced (p < 0.05) MDA level in renal tissue without restoring the erythrocyte MDA level following cDDP treatment. These observations were further supported by the histopathological findings in renal tissue. Observations of the present study have shown that treatments with ethanolic floral extract of C. officinalis protect cDDP induced nephrotoxicity by restoring antioxidant system of the renal tissue.

Our observations suggested that the concurrent exposure to CPF and fluoride increased the extent of renal damage. These findings indicate that this damage is due to increased free radical formation and a reduced function of the antioxidant system in renal tissue. Thus, the application of CPF as an insecticide should be reduced in areas where the fluoride levels in ground waters are high in order to minimize renal damage in exposed populations.

No abstract

Background and objectives: Drug induced hepatotoxicity is a major health issue concern by drug regulatory agencies, pharmaceutical industry and health care professionals. Present study was aimed to investigate the hepatoprotective mechanisms of n-hexane and acetone extract of Ageratum conyzoides on oxidative damage induced by acetaminophen (APAP) in Wistar rats. Materials and methods: 42 Wistar rats were randomly divided into seven groups. Group I and II receive distilled water, CMC respectively. Group III was fed with standard drug silymarin, group IV and V received plant extracts only whereas group VI and VII received pretreatment with acetone and n-hexane extracts for seven days respectively and APAP was administered on the 5th day. Samples were collected on 48 h of post APAP administration and analysis was done using standard protocols. Results: Significant (p < 0.05) increased in MDA, G6PD and GST and significant (p < 0.05) decrease in SOD, GSH, total thiols in liver tissue was observed in APAP exposed group as compared to control. The preexposure of acetone and n-hexane extracts of A. conyzoides fallowed by APAP exposure significantly (p < 0.05) reduce activities of G6PD, GST and MDA levels as compare to APAP exposed group, whereas total thiols and GSH levels are restored only in n-hexane extract of A. conyzoides. Conclusion: Observations of present study suggested that pre-exposure of n-hexane extract of A. conyzoides restore the levels of total thiols, GSH and GST activity which may be responsible for reducing oxidative damage induced by APAP administration.