Effect of curcumin analog on gamma-radiation-induced cellular changes in primary culture of isolated rat hepatocytes in vitro.

The present study was aimed to evaluate the radioprotective effect of curcumin analog, on gamma-radiation-induced toxicity in primary cultures of isolated rat hepatocytes. Hepatocytes were isolated from the liver of rats by collagenase perfusion. The DNA damage was analysed by single cell gel electrophoresis (comet assay). An increase in the severity of DNA damage was observed with the increase in gamma-radiation dose at 1-4 Gy in cultured rat hepatocytes. The levels of lipid peroxidative indices like thiobarbituric acid reactive substances (TBARSs) were increased significantly, whereas the levels of reduced glutathione (GSH) and antioxidant enzymes were significantly decreased in gamma-irradiated groups. The maximum damage to hepatocytes was observed at 4Gy gamma-irradiation. Pretreatment with different concentrations of curcumin analog (1.38, 6.91 and 13.82 microM) shows a significant decrease in the levels of TBARS and DNA damage. Pretreatment with curcumin analog prevents the loss of enzymic and non-enzymic antioxidants like GSH upon gamma-irradiation. The maximum protection of hepatocytes was observed at 6.91 microM of curcumin analog pretreatment. Thus, our result shows that pretreatment with curcumin analog protects the hepatocytes against gamma-radiation-induced cellular damage.

Lycopene as a natural protector against gamma-radiation induced DNA damage, lipid peroxidation and antioxidant status in primary culture of isolated rat hepatocytes in vitro.

The present study was designed to evaluate the radioprotective effect of lycopene, a naturally occurring dietary carotenoid, on gamma-radiation induced toxicity in cultured rat hepatocytes. The cellular changes were estimated using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), ceruloplasmin, vitamins A, E, C and uric acid. The DNA damage was analysed by single cell gel electrophoresis (comet assay). The increase in the severity of DNA damage was observed with the increase in gamma-radiation dose (1, 2 and 4 Gy) in cultured rat hepatocytes. TBARS were increased significantly whereas the levels of GSH, vitamins C, E and A, ceruloplasmin, uric acid and antioxidant enzymes were significantly decreased in gamma-irradiated groups. The maximum damage to hepatocytes was observed at 4 Gy irradiation. Pretreatment with lycopene (1.86, 9.31 and 18.62 microM) showed a significant decrease in the levels of TBARS and DNA damage. The antioxidant enzymes increased significantly along with the levels of GSH, vitamins A, E, C, uric acid and ceruloplasmin. The maximum protection of hepatocytes was observed at 9.31 muM of lycopene pretreatment. Thus, our results show that pretreatment with lycopene offers protection against gamma-radiation induced cellular damage and can be developed as an effective radioprotector during radiotherapy.

Effect of Ellagic Acid, a Plant Polyphenol, on Fibrotic Markers (MMPs and TIMPs) during Alcohol-Induced Hepatotoxicity.

ABSTRACT Alcoholic fibrosis and its end-stage cirrhosis occur when the rate of matrix synthesis exceeds matrix degradation. Hepatic fibroproliferation is associated with alterations of hepatic tissue inhibitors of matrix metalloproteinase (TIMPs) and matrix metalloproteinases (MMPs/matrixins) expressions. The alteration of hepatic matrixins and TIMPs expression to disease stage and inflammatory activity underlines their potential diagnostic markers in chronic liver disease. Ellagic acid (EA), a natural phenolic compound found in fruits and nuts, has potent antioxidant, anti-inflammatory, and anticancerous properties. The aim of our study was to gain further insight into the effect of EA on fibrotic markers (MMPs and TIMPs) during alcohol-induced tissue injury. To elucidate the effect on the MMPs/TIMPs balance by EA, gelatin zymography, multiwell zymography, succinylated gelatin assay, and ELISA technique (for TIMPs) were carried out. Coadministration of EA with alcohol decreased the expression of MMP-2 and -9 and TIMP-2 in a dose-dependent manner. These results suggest that EA at the dosage of 60 mg/kg body weight effectively decreased the expression pattern of fibrotic markers during alcohol-induced toxicity. Hence, it can be developed as an antifibrotic compound in near future.

Modulatory effects of curcumin on γ-radiation-induced cellular damage in primary culture of isolated rat hepatocytes.

Ionizing radiation is known to induce oxidative stress through generation of reactive oxygen species (ROS) resulting in imbalance of the pro-oxidant and antioxidant in the cells, which is suggested to culminate in cell death. The present work was aimed to evaluate the radioprotective effect of curcumin, a yellow pigment of turmeric on γ-radiation-induced toxicity in primary cultures of isolated rat hepatocytes. Hepatocytes were isolated from the liver of rats by collagenase perfusion. The cellular changes were estimated using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH), ceruloplasmin, vitamins A, E and C and uric acid. The comet assay is a sensitive and rapid technique for quantifying and analyzing DNA damage in individual cells was exposed under γ-radiation. The increase in the severity of DNA damage was observed with the increase dose (1, 2 and 4Gy) of γ-radiation in cultured hepatocytes. TBARS were increased significantly, whereas the levels of GSH, vitamins C, E and A, ceruloplasmin, uric acid and antioxidant enzymes were significantly decreased in γ-irradiated hepatocytes. The maximum damage to hepatocytes was observed at 4Gy irradiation. On pretreatment with curcumin (1, 5 and 10µg/ml) showed a significant decrease in the levels of TBARS and DNA damage. The antioxidant enzymes were increased significantly along with the levels of GSH, vitamins A, E and C, uric acid and ceruloplamin. The maximum protection of hepatocytes was observed at 10µg/ml of curcumin pretreatment. Thus, pretreatment with curcumin helps in protecting the hepatocytes against γ-radiation-induced cellular damage and can be developed as an effective radioprotector during radiotherapy in near future.

Influence of ferulic acid on gamma-radiation induced DNA damage, lipid peroxidation and antioxidant status in primary culture of isolated rat hepatocytes.

Ionizing radiation is known to induce oxidative stress through generation of reactive oxygen species (ROS) resulting in imbalance of the pro-oxidant and antioxidant activities ultimately resulting in cell death. Ferulic acid (FA) is a phytochemical commonly found in fruits and vegetables such as tomatoes, sweet corn, and ricebran. FA exhibit a wide range of pharmacological effects including antiageing, anti-inflammatory, anticancer, antidiabetic, antiapoptotic, and neuroprotective. The present work is aimed at evaluating the radioprotective effect of FA, on gamma-radiation induced toxicity in primary cultures of isolated rat hepatocytes. Hepatocytes were isolated from the liver of rats by collagenase perfusion. The cellular changes were estimated using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH), ceruloplasmin, Vitamins A, E and C and uric acid. DNA damage was analyzed by single cell gel electrophoresis (comet assay). An increase in the severity of DNA damage was observed with increasing dose (1, 2 and 4Gy) of gamma-radiation in cultured hepatocytes. TBARS were increased significantly, whereas the levels of GSH, Vitamins C, E and A, ceruloplasmin, uric acid and antioxidant enzymes were significantly decreased in gamma-irradiated groups. The maximum damage to hepatocytes was observed at 4Gy irradiation. Pretreatment with FA (1, 5 and 10 microg/ml) significantly decrease the levels of TBARS and DNA damage. In addition, pretreatment with FA significantly increased antioxidant enzymes, GSH, Vitamins A, E and C, uric acid and ceruloplasmin levels. The maximum protection of hepatocytes was observed at 10 microg/ml of FA pretreatment. Thus, pretreatment with FA helps in protecting the hepatocytes against gamma-radiation induced cellular damage and can be developed as a effective radioprotector during radiotherapy.