Effects Of Berberine On The Expression Of PDX-1 And IGF-1 In Pancreatic Islets In Rats With T2DM

Objective: PDX-1 and IGF-1 play an important role in the occurrence and development of diabetes.Berberine has been shown to improve glucose metab-olism and insulin resistance.In this study,rat models of T2DM were established by combination of intraperitoneal injection of low-dose streptozotocin and high -glucose-high-fat diet induction. To observe the effect of berberine on fasting glucose,fasting serum insulin,HOMA-IR, HOMA-IS expression of PDX-1and IGF-1 of pancreatic islets in rats with T2DM.The present study aimed to evaluate the antidiabetic efficacy of berberine and study the mechanism of its therapeutic effect preliminary.Methods: 40 healthy adult male SD rats,by random number table to access 6 rats for normal controls group and fed a standard diet,and the remaining rats given a intraperitoneal injection of streptozotocin.The rats with FBG greater than 13.8 mmoL/L were randomly divided into diabetes mellitus group and berberine group,fed high sugar high fat diet for two weeks,and then continued on a standard diet,and the berberine group were given berberine (180mg / kg ? d) every day,the normal controls group and diabetes mellitus group were given physiological saline for every day 6 weeks. At the end of 6th week,the rats were executed,and the level of fasting glucose,fasting serum insulin,HOMA-IR, expression of PDX-1 and IGF-1 in pancreas isle of each group were detected.The expression of PDX-1 and IGF-1 in pancreas islet examined by was Immunohistochemistry.The Image pro plus 6.0 software was applied to calculate the integrated optical density(IOD) and positive area of positive expression.Results: (1). FBG,FINS and HOMA-IR:Berberine improved FBG and insulin sensitivity in rats with T2DM.Compared with the normal control group,the FBG,FINS,HOMA-IR of the diabetes mellitus group were significantly increased(P:0.000,0.000,0.000), and the FBG, FINS, HOMA-IR of berberine group were also significantly increased(P:0.005,0.014,0.008). Compared with the diabetes mellitus group, the FBG,FINS,HOMA-IR of berberine group were significantly decreased(P:0.004,0.042,0.003).(2). IS and PDX-1: Compared with the normal control group,the IS of the diabetes mellitus group and berberine group were decreased(P:0.002,0.001), After 6-week treatment with berberine, the IS of the berberine treatment rats was no difference compared with the diabetes mellitus group(P:0.653);Berberine increased the expression of PDX-1 in the pancreas islet in rats with T2DM Compared with the normal control group, the IOD of PDX-1 of the pancreas islet of the diabetes mellitus group and berberine group was statistically significant decreased(P:0.000,0.038),the positive area of positive expression of the diabetes mellitus group and berberine group was decreased(P: 0.000,0.021). After 6-week treatment with berberine,the IOD and positive area of PDX-1 of the pancreas islet of the berberine treatment rats was significant increased compared with the diabetes mellitus group(P:0.003, 0.023). (3). IGF-1: Berberine make no difference for the expression of IGF-1 in pancreas islet in rats with T2DM.Compared with the normal control group, the IOD of IGF-1 of the pancreas islet of the diabetes mellitus group and berberine group was statistically significant decreased(P:0.01,0.01),the positive area of positive expression of the diabetes mellitus group and berberine group was decreased(P:0.078,0.001). After 6-week treatment with berberine,the IOD of IGF-1 of the pancreas islet of the berberine treatment rats was no difference compared with the diabetes mellitus group(P:0.275),athough the positive area of IGF-1 of berberine group was decreased(P:0.021) .Conclusions: 1. Berberine improved FBG and insulin sensitivity in rats with T2DM. 2. Berberine increased the expression of PDX-1 in the pancreas islet in rats with T2DM. The increase expression of PDX-1 in pancreas islet may be one of the mechanism of berberine in the improvement of hyperglycemia.3. Berberine make no difference for the expression of IGF-1 in pancreas islet in rats with T2DM.