Effects Of 1,25-dihydroxyvitamin D₃ On The Adipokine And Inflammatory Markers In Type 2 Diabetic Rats

Objective:Through using 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] during the process of making type 2 diabetic rats model and investigating the effects of 1,25-dihydroxyvitamin D3 on the adipokine and inflammatory markers of type 2 diabetic rats, to explore the protective effects of 1,25-dihydroxyvitamin D3 on the pathogenesis of type 2 diabetic rats.Methods:Male Sprague-Dawley rats,8 weeks old, were divided randomly into 3 groups: normal rats,1,25-(OH)2D3 intervention diabetic rats(vitamin D intervention diabetic rats)and non-1,25-(OH)2D3 intervention diabetic rats(non-vitamin D intervention diabetic rats). Vitamin D intervention diabetic rats and non-viatamin D intervention diabetic rats were injected with streptozotocin(STZ,30mg/kg intraperitonealy)to establish type 2 diabetic rats model after 6 weeks. One week later, the incidence of diabetes was observed and body weight, fasting glucose, triglyceride, total cholesterol, calcium, phosphorus were measured. Radio-immunnity analysis was used to detect the fasting insulin, leptin, TNF-a, IL-6. Serum adiponectin was measured by ELISA, adiponectin mRNA level in adipose tissue was examined by RT-PCR.Results:1) Compared to normal rats, fasting glucose, fasting insulin, total cholesterol, leptin, calcium, phosphorus were increased in diabetic rats(including non-vitamin D intervention diabetic rats and vitamin D intervention diabetic rats)(P<0.05). Triglyceride, IL-6, TNF-a were increased, but serum adiponectin and adiponectin mRNA level in adipose tissue were decreased in non-vitamin D intervention diabetic rats compared to normal rats(P<0.05).2) Fasting insulin, IL-6, TNF-a were decreased, but serum adiponectin and adiponectin mRNA level in adipose tissue were increased in vitamin D intervention diabetic rats compared to non-vitamin D intervention diabetic rats(P<0.05). 3) There were no differences between vitamin D intervention diabetic rats and non-vitamin D intervention diabetic rats in fasting glucose, triglyceride, total cholesterol, leptin, calcium, phosphorus (P>0.05).4) The incidence of diabetes was equal between vitamin D intervention diabetic rats and non-vitamin D intervention diabetic rats. Conclusion:1,25-(OH)2D3 has protective effects on the pathogennesis of type 2 diabetic rats in molecular level through decreasing serum TNF-a, IL-6 and increasing adiponectin mRNA level in adipose tissue.