Silymarin, a flavonoid and widely used drug and supplement for various liver disorders. Liver disorder is one of the most common lesions which have been recirde after whole-body gamma irradiation of experimental animals. Considering the anti-hepatotoxic activity of silymarin, together with its strong antooxidative and radioprotective efficacy, the objective of this study was planned to detect to what extent silymarin can ameliorate the radiation-induced toxicity of the hepatic tissue at the histochemical level. Forty adult male albino rats have been used for this study and classified equally into 4 groups; normal rats, gamma-irradiated (5Gy) rats, silymarin administrated and gamma- irradiated rats, control rats (treated with silymarin only). Silymarin was administered by oral gavages, at a dose of 70 mg/Kg, one hour before irradiation. Liver sections were prepared from each group and stained with PAS reaction for carbohydrates, mercury bromophenol blue (MBB) for total protein and Feulgen reaction for DNA. These histochemical sections of control liver and treated animals were subjected to the image analysis for the quantitative measurements of the optical density (OD) of the previously mentioned histochemical components. The histochemical examination and the quantitative measurements of the liver sections of gamma-irradiated rats resulted in many histochemical alterations such as an obvious loss of the total carbohydrate content, an increase and accumulation of protein as an indicator for protein degradation and marked decrease in the DNA content. These alterations were more prominent on the first and third days post irradiation. Silymarin treatment prior to irradiation succeeded to minimize the loss of the carbohydrate materials, increase the hepatocyte protein synthesis, protect against radiation induced suppression of hepatic DNA and support the liver tissue in the process of recovery, repair and restoration of the normal picture of the previous histochemical components. These results suggest and confirm the prophylactic and radioprotective role of silymarin for the histochemical pattern of the hepatic tissue against radiation-induced toxicity. Quantification of the histochemical sections supported the hepatoprotective effect of silymarin. |
