Relationship Between The Levels Of Vitamin D₃ And Early-phase Insulin Secretions In Type 2 Diabetes

Objectives:Study the relationship between the levels of 25(OH)D3 and early-phase insulin secretions in type 2 diabetes(T2DM).Methods:(1)40 new-diagnosised T2DM subjects,50 treated T2DM subjects,40 IGT/IFG subjects and 40 health subjects were divided into DM1,DM2,DM0 and control group respectivesly. The levels of 25(OH)D3 in their blood serum were determined by ELISA,and OGTT, FPG,FINS,G30,I30 as well as index of△I30/△G30 and Homa-β. The relationship between the levels of 25(OH)D3 and△I30/△G30 or Homa-βalso was analysesed.(2)20 new-diagnosis T2DM subjects and 20 treated T2DM subjects were selected, 10 subjects of them as treated group and 10 subjects of them as control group respectivesly, and the treated group disposaled with 25(OH)D3 for 20 weeks.The levels of 25(OH)D3 and△I30/△G30 or Homa-βwere compared between the treated group and control group after 20 weeks.Results:(1)The levels of 25(OH)D3 in 4 groups were difference significantly(p<0.05), and that in DM0,DM1 and DM2 group were higher than control group(7653.25±1431.56 mg/L,5896.09±1168.78 mg/L&4094.72±1012.02 mg/L vs 9706.33±1667.57 mg/L ,respectivesly)(p all <0.05). (2)The levels of△I30/△G30 and Homa-βin 4 groups were difference significantly(p <0.05), and that in DM0,DM1 and DM2 group were higher than control group(p <0.05);The 3 abnormal groups were diveded into A,B and C group, according to the difference levels of 25(OH)D3(<4000mg/L,4000～7000mg/L & >7000mg/L ,respectivesly).The levels of△I30/△G30 and Homa-βin 3 groups were difference significantly(p <0.05), and that in A group were the lowest,that in B group were middle,that in C group were the highes(p<0.05,respectivesly).(3)The 3 abnormal groups were diveded into NO1,2,3 group,according to the difference levels of△I30/△G30(<1.0,1.0～2.0 & >2.00, respectivesly),The levels of 25(OH)D3 in 3 new groups were difference significantly(p<0.05), and that in NO1 group were the lowest, that in NO2 group were middle,that in NO3 group were the highest(p<0.05, respectivesly);The 3 abnormal groups were diveded into"a","b"and"c"group according to the difference levels of Homa-β(<3.0,3.0～5.0&>5.00 ,respectivesly),The levels of 25(OH)D3 in 3 new groups were difference significantly(p<0.05),and that in"a"group were the lowest, that in"b"group were middle, that in"c"group were the highest (p<0.05,respectivesly). (4)The positive linkage between the levels of the 25(OH)D3 and△I30/△G30 were showed by correlation analysis(r=0.40,p<0.05);The positive linkage between the levels of the 25(OH)D3 and Homa-βwere showed by correlation analysis(r=0.29,p<0.05);The positive linkage between the levels of the G30,△I30,△G30,FPG,HbA1C,25(OH)D3 and△I30/△G30 were showed by multiple linear regression analysis(r=0.84,-0.61,-0.24,0.16,0.12,respectivesly,p<0.05); The positive linkage between the levels of the G30,△I30,△G30,FPG,HbA1C,25(OH)D3 and Homa-βwere showed by multiple linear regression analysis (r=0.52,0.23,0.58,0.17,respectivesly,p <0.05).(5)The levels of 25(OH)D3 in the treated T2DM subjects were higher than that in control group after disposaled with 25(OH)D3 for 20 weeks(p<0.05,respectivesly).The levels of△I30/△G30 and Homa-βin treated group were higher than that in control group (p<0.05,respectivesly).The levels of△I30/△G30 and Homa-βwere higher than that in treated group before disposaled (p<0.05,respectivesly).Conclusions:(1) Type 2 diabetes had lower vitamin D levels, and the levels of vitamin D were related with their DM course.(2)The levels of vitamin D were correlated with early-phase insulin secretions in type 2 diabetes.(3)Disposaling with vitamin D properly would improved their early-phase insulin secretions in type 2 diabetes.(4)Vitamin D was one of the factors impacting the early-phase insulin secretion.