Effects Of 1α,25-dihydroxyvitamin Vitamin D₃ On Treg Cells In Rats With IgA Nephropathy

Objective:Active vitamin D3,is best known as 1α,25-dihydroxyvitamin D3(1, 25(OH)2D3)and its main physiological function is to regulate the body’s bone and calcium metabolism. A large number of epidemiological data suggested that the deficiency of the 1, 25- dihydroxy vitamin D3 can increase the risk of autoimmune disease. It may be related to the vitamin D receptor(VDR) in immune cells, which plays an important role in immune regulation after combination. Regulatory T cells are one of the subsets of CD4+T cell,which play a role in suppressing T lymphocyte activation and proliferation, and maintain the body’s immune tolerance to prevent the occurrence of autoimmune disease, graft rejection and tumor immune resistance. In our study we explore the effects of 1,25-dihydroxyvitamin D3 on regulatory T cells in rats with Ig A nephropathy(Ig AN).Method:1)We choosed Wister 52 rats,with witch 8 rats were choosed in control group(group A)in random,while other 44 rats were established the Ig A nephropathy model by mucosal immune with bovine serum albumin; 2) 32 rats were randomly assiged to model group(group B), 1, 25(OH)2D3 treatment group(group C), prednisone treatment group(group D), and prednisone and 1, 25(OH)2D3 combined treatment group(group E) except for the dead rats. The treatment group were given drug intervention respectively, while control group and model group were given equal normal saline; 3) The urine red blood cell, the 24-hour urine protein and the serum calcium were measured. The levels of the Foxp3 m RNA were assayed by real-time polymerase chain reaction, and the levels of the Foxp3 protein expression in spleen lymphocytes were detected by Western blot.Results:(1) The changes of urine red blood cell in each group: Compared with normal control group, the urine red blood cell in the model group was significantly increased, the difference was statistically significant(p < 0.05); Compared with model group, the urine red blood cell in the 1, 25(OH)2D3 treatment group, the combination group and prednisone treatment group were decreased, the difference was statistically significant(p < 0.05), especially the combination group was reduced significantly.(2) The changes of the 24-hour urine protein in each group: Compared with normal control group, the 24-hour urine protein in the model group was significantly increased, the difference was statistically significant(p < 0.05);Compared with model group, the 24-hour urine protein in the 1, 25(OH)2D3treatment group, the combination group and prednisone treatment group were decreased, the difference was statistically significant(p < 0.05), especially the combination group was reduced significantly.(3) The level of blood calcium changes in each group groups : The changes of the blood calcium were slightly, the difference is not statistically significant.(4)The changes about the level of Foxp3 m RNA expression in the rat spleen lymphocytes :Compared with normal control group, the level of Foxp3 m RNA expression in the model group was significantly decreased, the difference was statistically significant(p < 0.05); Compared with model group, the level of Foxp3 m RNA expression in the 1, 25(OH)2D3 treatment group, the combination group and prednisone treatment group were increased, the difference was statistically significant(p < 0.05), especially the combination group was increased significantly.(5) The changes about the level of Foxp3 protein expression in the rat spleen lymphocytes :Compared with normal control group, the level of Foxp3 protein expression in the model group was significantly decreased,the difference was statistically significant(p < 0.05); Compared with model group,the level of Foxp3 m RNA expression in the 1, 25(OH)2D3 treatment group, the combination group and prednisone treatment group were increased, the differencewas statistically significant(p < 0.05), especially the combination group was increased significantly.Conclusion:1, 25-dihydroxyvitamin D3 might reduce the level of urinary protein, the protective role of which on Ig A nephropathy might be associated with the regulation of Foxp3 expression in rats with Ig A nephropathy.