Isolation Of Insulin-like Growth Factor-Ⅰ From Bovine Colostrums And Research Of It's Preventive Effect On Diabetes

The subject of this research is to separate insulin-like growth factor-â… (IGF-â… ) from bovine colostrums and to observe the preventive effect of IGF-â… in bovine colostrums (BC-IGF-I) on diabetic rats. The results are as follow:Using the extraction of acid-ethanol and gel filtration chromatography methods, IGF-â… was isolated and purified from colostrums. The total recovery of IGF-â… was 46.87%.The content of IGF-â… was 0.859mg/g,386 times higher than colostrums.The preventive effect of IGF-â… on diabetic rats was evaluated. The results of weight,food intake and water intake were: There are remarkable differences between the BC-IGF-I groups and control group on weight,food intake and water intake after streptozotocin had been induced. And the rats of control group had performed the diabetic symptoms as"polydipsia"and"weight reduction".But there was not any improvement on the symptom of polyphagia.Serum detection by enzymic methods. The results showed: Although the level of glucose,GSP,T-CHO and TG couldn't been controlled to the normal state ,the value of BC-IGF-I groups were obviously lower than that of control group and tend to be down. And there was a dosage effect among the BC-IGF-I groups. Indicated that oral administration BC-IGF-I previously could delay the hyperglycemia and hyperlipemia.Serum homone level of all rats were measured by radioimmunoassay. The results showed: oral administration BC-IGF-I previously could control the serum insulin and free IGF-â… level and growth homone level effectively, accordingly to improve the Hormone disturbance.Weight of pancreas/Body weight showed that : Weight of pancreas could be retained by oral administration BC-IGF-I previously. The cell of pancreas was observed by micrography. It showed that IGF-I could protect the pancreas away from the damage of streptozotocin.Glucose resistence was improved by oraling administration BC-IGF-I previously. Based on research results, the preventive effect mechanism on diabetes of IGF-â… was deduced. It is that :IGF-I could protect the pancreas away from the damage of streptozotocin, keep the structure and function of the pancreas. So the preventive effect on diabetes would be achieved.