Potential Therapy for Multiple Sclerosis (MS): Investigating the effects of 1,25-dihydroxycholecalciferol on T regulatory cells in Patients with MS

The active form of 1,25-dihydroxycholecalciferol and mesenchymal stem cells (MSCs) have immunomodulatory effects on the immune system and could be helpful for regenerative therapeutic application in neurodegenerative diseases. The MSCs were isolated from adipose tissue and characterized using surface CD markers pattern and differentiation capacity into adipose and osteocyte lineages. After that, the confirmed MSCs were cultured in the presence of different concentrations of 1,25-dihydroxycholecalciferol (6, 12, 25, 50, 100 nM and 0 as control). Finally, the MSCs proliferation and apoptosis were evaluated by 3-(4,5-dimethylthiazohl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry tests, respectively. The gene expression of inflammatory and anti-inflammatory cytokines was measured by real-time PCR and regulatory T cells (Tregs) population using flow cytometry techniques. Also, anti-oxidant parameters including NO, MDA, and SOD activity were measured. Our findings indicated that 6, 12, 25 and 50 nM concentrations of 1,25-dihydroxycholecalciferol significantly increased AT-MSCs viability, protecting them against apoptosis and also expanded Tregs proportion. Furthermore, 1,25-dihydroxycholecalciferol induced higher expression levels of anti-inflammatory markers, while 1,25-dihydroxycholecalciferol decreased the expression of inflammatory cytokines. In addition, the 1,25-dihydroxycholecalciferol at concentrations of 100 nM decreased nitrite oxide content. This study demonstrated that 1,25-dihydroxycholecalciferol is effective in the AT-MSCs by inducing regulatory, anti-oxidant, and anti-apoptosis effects. The main conclusion of this study is that 1,25-dihydroxyvitamin D3 can act as a beneficial synergistic factor in treating patients undergoing stem cell therapy.