The Research Of Antioxidative Effect Of Liuyueqing Fractions In Vitro

Objective:To extrat and purify liuyueqing and study the antioxidative effect of liuyueqing fractions in vitro. Methods: 60% ethanol extracts were purified by AB-8 macroporous adsorptive resin and fractions A-E were obtained by gradient elution water-and-alcohol as elution system. The effect of LYQ fractions A-E on superoxide anion (O2·-) was investigated by the auto-oxidation of pyrogallol and their effect on hydroxyl free radical (·OH) was measured by Fe2+-H2O2 system. MDA content in liver was measured by thiobabituric acid assay, the hemolysis of RBC and the swelling extent of mitochondria were detected by spectrophotometric methods. The main component of fraction A was identified by chemical methods. Results: LYQ fraction A could inhibit the generation of MDA, the hemolysis of RBC, the swelling of mitochondria, and the productions of·OH and O2·-, the main component of fraction A was polysaccharides. Conclusion:LYQPS posses a good antioxidative effect in vitro. Objective: To extract and purify the LYQPS and to determine the median lethal dose of LYQPS. Methods: The LYQ crude polysaccharides was obtained with the water extraction and alcohol precipitation method, then the crude LYQPS was deproteinized according to the method of Sevag, and decolourized by using H2O2 method at last. Glucose was used as standard in the preparation of calibration curve. The content of LYQPS was determined by phenol-vitriolic method. The median lethal dose(LD50) was measured by Bliss method. Results: The content of LYQPS was 71.80%, The median lethal dose(LD50) was 21.8g/kg and the 95% confidence interval was 18.3~26.1g/kg. Conclusion: LYQPS prepared by our method has high purity and low toxicity. LYQPS can be used for its further researches of Pharmacological activities. Objective: To observe the protective effect of Liuyueqing polysaccharides (LYQPS) on liver injury induced by Carbon Tetrachloride in mice. Methods: The model of CCl4 induced acute liver injury in mice with the method of intraperitoneal injection was used to study the protective effect of LYQPS. Kunming mice were randomly divided into NC group, liver-injured group, high-, medium- and low- dose of LYQPS groups (0.28, 0.14 and 0.07 g/kg respectively), and biphenyldicarboxylate (BPDC) group. The indexes of liver, spleen and thymus were observed. The activity of AST, ALT and AKP, the content of Alb, the ability of T-AOC in serum, the content of MDA, and the activity of SOD in liver tissue were investigated. Hematoxylineosin (HE) stain was used to examine the degree of hepatic injury. Results: Compared with model group, LYQPS could obviously reduce the indexes of liver and spleen, but have no effect on the weight of thymus. The activities of AST, ALT and AKP, and the content of MDA could be down-regulated; the content of Alb, the ability of T-AOC, and the activity of SOD could be increased (P<0.01 or P<0.05). The degree of hepatic injury could be lessened. Conclusion: LYQPS has protective effect on acute liver injury induced by CCl4. The mechanism may be related to attenuating free radical and inhibiting the effect of lipid peroxidation. Objective: To observe the protective effect of LYQPS on immunity liver injury induced by concanavalin A in mice. Methods: 90 Kunming mice were injected with Con A (20mg/kg) via the tail at the first day of the experiment and then randomly divided into Con A group, high-, medium- and low- dose of LYQPS groups, and biphenyldicarboxylate (BPDC) group. 18 Kunming mice were used as NC group. All mice were administered with corresponding drugs by gastric perfusion at 8 hour after Con A administration. All the drugs were given once daily for 3 days consecutively. Four hours after the last administration of drugs, mice were injected with Con A once again at the same dosage. Blood samples for determining TNF-αconcentration were collected at 2 hour after Con A administration. The activities of AST, ALT and AKP in serum, the content of NO in hepatic microsome, the activity of SOD, the content of MDA and the expressions of Fas and FasL in liver tissue were investigated at 8 hour after Con A injection. Histopathological examination was also perfomed for liver tissue. Results: Compared with model group, LYQPS could obviously reduce the activities of AST, ALT and AKP, the contents of TNF-α, NO and MDA, and the expressions of Fas and FasL. The activity of SOD could be increased (P<0.01 or P<0.05). The pathological changes in liver tissue were lessened. Conclusion: LYQPS has protective effect on immunity liver injury induced by Con A. The mechanism may be related to down-regulation of TNF-α, antiapoptosis and inhibiting the lipid peroxidation.