1,25-(OH)_2D_3对NOD小鼠T淋巴细胞凋亡率的影响

Effects of 1,25-dihydroxyvitamin D_3 on apoptosis of T lymphocytes in nonobese diabetic mice

目的 通过对NOD小鼠T淋巴细胞凋亡率的分析 ,揭示 1,2 5 - (OH) 2 D3 的免疫调节机制。方法 将经环磷酰氨(CYP)加速过的 4 0只体重相近的 4周龄NOD小鼠脾细胞制成单细胞悬液 ,一方面抽提DNA ,经凝胶电泳DNA梯度图谱定性分析T淋巴细胞凋亡率 ;另一方面经流式细胞仪对其凋亡率进行定量测定。结果 处理组发病率降低 (P <0 0 1) ;外周T淋巴细胞凋亡率增加 (P <0 0 5 )。结论 1,2 5 - (OH) 2 D3 能够通过增加T淋巴细胞的凋亡减少免疫效应性细胞的积聚而阻止NOD小鼠发生

Objective To investigate the effects of 1,25-dihydroxyvitamin D 3 on apoptosis of T lymphocytes in nonobese diabetic mice. Methods Forty female 4 week NOD mice (18 g)were randomly divided into two equal groups. Group1 received the intraperitoneal injection of 1,25-dihydroxyvitamin D 3(5 μg/kg)every other day. Group 2 received the intraperitoneal injection of peanut oil (equal quantity and times). The mice in two groups were given cyclophosphamide(250 mg/kg) to accelerate the process of diabetes at day 1. All mice were killed at day 30. The incidence of diabetes, the degree of insulitis and apoptosis rate of spleen lymphocytes were detected by DNA ladder qualitative analysis and by flow cytometry quantitative analysis. Results Intraperitoneal injection of 1,25-dihydroxyvitamin D 3 to NOD mice reduced the incidence of diabetes( P <0 01). The insulitis score and the severity of insulitis 1,25-dihydroxyvitamin D 3 mice were lower than those of the control group ( P <0 01). Therate of apoptosis was higher than those of the control group ( P <0 05). Conclusion These results show that 1,25-dihydroxyvitamin D 3 could prevent NOD mice from developing into type 1 diabetes by incereasing apoposis of T lymphocyte to decrease accumulation of inmmune effective cells.