Vitamin D Regulation Of The Significance Of Type 2 Diabetes Prevention And Control

Objective: To explore the relationgship between vitamin D and type 2 diabetes mellitus and the significance of treatment by regulating vitamin D level. Methods:①Enzyme linked immunosorbent assay (ELISA) was used for the detection of serum 1,25(OH)₂D₃, and clinical and biochemical indexes were also detected.②The polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP) was used to detect VDR and DBP genotype in 105 type 2 diabetic patients and 105 normal controls . The alleles frequencies and genotype frequencies of VDR and DBP gene were compared between the twp groups, and serum 1,25(OH)₂D₃ and other indexes were compared between the different genotypes.③Screening blood serum 25(OH)D<75nmol/l 31 cases from 78 cases of type 2 diabetes mellitus and healthy volunteers.21 patients with type 2 diabetes and 10 healthy volunteers were given orally Alpha-D3 1 ug/d for 3months. Then to observe the differences of blood serum 25 ( OH ) D , calcium, phosphonium, renal function,glycosylated hemoglobin,urinary albumin pre and post treatment.Result:①There was an obvious difference of blood serum 1, 25(OH)₂D₃ between the case and control group (P < 0.01). There was a significant negative correlation between blood serum 1,25(OH)₂D₃ and fasting blood glucose(rs=-0.696,p<0.01).②There was significant difference in the distrubution of VDR genotype frequencies and alleles frequencies between the two groups( P < 0.01), the prevalence of VDR gene genotype frequencies and alleles frequencies in type 2 diabetic patients was significantly different from the other group. Serum 1,25(OH)₂D₃ was higher in VDR genotype AA and Aa groups than in genotype aa groups, while systolic blood pressure, diastolic blood pressure and fasting blood glucose were lower(P<0.05或0.01).③There was no difference in the distrubution of DBP genotype frequencies and alleles frequencies between the two groups( P>0.05), Serum 1,25(OH)₂D₃ was no difference among the different DBP genotypes(P>0.05).④There was an obvious improvement of blood serum 25(OH) D after oral Alpha-D3 in both diabetic and health group (P < 0.01). Urinary albumin evidently declined after treatment in diabetic group(P<0.05). There was a positive correlation between blood serum 25(OH) D and and blood phosphonium(p<0.05).Conclusion:①Blood serum 1,25(OH)₂D₃ in the case group was significantly lower than that in the control group. The higher fasting blood glucose, the lower blood serum 1,25(OH)₂D₃.②Apa I polymorphism of VDR gene was associated with type 2 diabetes. Serum 1,25(OH)₂D₃, fasting blood glucose and blood pressure were also associated with VDR gene polymorphism.③Asp416Glu and Thr420Lys polymorphism of DBP receptor gene was not associated with type 2 diabetes and serum 1,25(OH)₂D₃.④Oral Alpha-D3 treatment significantly increased the blood serum 25(OH) D, decreased the urinary albumin. It imply that vitamin D3 has renal protective effects.