The Purification, Biological Characterization And Primary Pharmacodynamic Study Of Sharp Hepatic Stimulator Substance

Sharp Hepatic Stimulator Substance (sHSS) is extracted from sharp liver which can promote and protect hepatic function. This subject includes the purification of sHSS from little shark, studying it's effect on proliferation of hepatocyte and the respiratory function and antioxidant capacity of mitochondria during acute hepatic injury were investigated.Shark hepatic stimulator substance were purified through 70 ℃-heating, 40% cold ethanol precipitation. DEAE-Sepharose column, Sephacryl S-100 column and HPLC guided by [ H] — thymidine incorporation into DNA. The presents paper reported the 294 lu/ mg proyein specificactivity with an approximately 56.8-fold increase in specific growth stimulator activity compared to 70℃-heating HSS. At last, we got the protein N-terminal sequencing result: S, W, N, W, S;N, V, T, V, W.Effect of sHSS on proliferation of HepG 2 cells was measured by [~3H] — thymidine incorporation into DNA. After exposed to sHSS, [~3H]—thymidine incorporation into DNA. was significantly increased. Index of stimulator (IS) was 5.33 at a dosage of 160 μ g protein/ml.The experimental models of acute hepatic injury were established. SHSS administration significantly suppressed the elevation of aspartic aminotransferase (AST) and alanine aminotransferase (ALT), and successfully improved survival in rats with TAA-induced acute hepatic injury. Liver histological changes indicated that sHSS reduced the severity of hepatic and hepatocyte lesion induced by TAA administrationThe TAA administration decreased the ADP-stimulated oxygen consumption, respiratory control ratio (RCR), the ADP/O value and oxidative phosphorylation ratio for both substrate oxidation of site Ⅰ and Ⅱ, in isolated mitochondria. These alternations were paralleled by a decrease in the NADH-cytochrome c reductase, succinate-cytochrome c reductase, cytochrome coxidase and ATPase activities. The sHSS administration reversed these changes. The swelling and the collapse of membrane potential of liver mitochondria could not be induced by TAA and sHSS. These illustrated that sHSS could prevented the impairment of mitochondrial respiratory function induced by TAA administration.TAA administration decreased the levels of glutathione, glutathione peroxidase, glutathione reductase and superoxide dismutase in mitochondria, and increased hepatic and mitochondrial MDA levels. SHSS administration reversed these changes. These illustrated that sHSS extract could increase hepatic and mitochondrial antioxidant defenses in rats with TAA induced acute hepatic injury.