Study On Extract Of Oleanolic Acid From Ligustrum Lucidum Ait And Its Hypoglycemic Effects

Diabetes Mellitus (DM),a severe,chronic form of endocrinopathic metabolic disease, Now diabetes has been one of the leading cause of death.Thus the screening of new compounds including plant extracts for antidiabetic effects is mandatory.In the research of antidiabetic medicament,there are many evident side-effects of the synthetic medication during treatment.So screening effective and lowering side-effect medication becomes very important in Chinese herb investigation.The extraction of Oleanolic acid which from Ligustrum lucidum Ait was used,antidiabetic function and it's mechanism was researched.(1)The separating procedures of Oleanolic acid from Ligustrum lucidum Ait was researched.The main separating procedures were described as follows,Dried fruits of Ligustrum lucidum Ait,Dissociation on shelled rapeseed,Ultrasonic Extraction with ethanol of 95 percent,Acid precipitation,Alkali treatment,Salting-out,Acid treatment,decolour with activated carbon,Degreasing with n-hexane and then freezedried to get powde.then recrystallized into white needle crystal-oleanolic acid.By determination,The effective component had a good solubility in 95%ethanol,[a]D21=+73.3°.The results showed that the oleanolic acid in white needle crystal was about 96.98%.(2)Optimal experimental conditions for establishing a diabetic model with alloxan in ICR mice,Result shows the optimal dosage of alloxan about female mice with body weight 18～22 g was 260 mg/kg.The male mice was 270 mg/kg.(3)The alloxan-induced hyperglycemic mice were randomized to three groups,diabetes vehicle group,oleanolic acid group,glibenclamide group and normal mice were set up as vehicle group.result shows administration of OLA significantly decreased fasting blood glucose levels,serum contents of TC,TG,LDL-c,and effectively increased HDL-c in diabetic mice (P<0.05).The levels of AST,ALT,HbA1-c,and ALP were significantly increased in the plasma of untreated alloxan-diabetic mice compared to normal vehicle group(P<0.05),and decreased in OLA-treated diabetic mice(P<0.05).Furthermore,OLA treatment significantly blocked the increase of MDA in liver and kidney tissues(P<0.05),but increased SOD,T-AOC and GSH-Px levels in diabetic mice (P<0.01).Immune organ's index means OLA can increase the spleen index and thymus index(P<0.05).Histopathological results showed that OLA could restore the damage of pancreas tissues in diabetic mice.These result shows OLA can remove the free radical,increase antioxidation, improve immunity,protect liver,kidney and pancreatic cells from alloxan induced injuries.By through these ways we know OLA improved the symptoms of alloxan-induced diabetes in our mouse model,decrease serum glucose in alloxan-induced hyperglycemic mice.