In vitro Effect of Vitamin D on the Levels of Cytokines and Apoptosis Related Markers in Systemic Lupus Erythematosus

Background: Both genetic and environmental factors are responsible for systemic lupus erythematosus (SLE) pathogenesis. knowledge about the roles of cytokines and apoptosis in SLE have led to new clinical points of view in its pathogenesis. Objective: This work aimed to study the in vitro effects of vitamin D3 on the level of IL-6, TNF-α, INF-γ, and IL-10 cytokines, as well as the expression of Bax and Bcl-2 in peripheral blood mononuclear cells (PBMCs) cultures of SLE patients. Methods: Isolated PBMCs from 50 SLE patients were cultured with 1,25(OH)2D3. Vitamin D treated cultured cells were assessed for detection of the levels of cytokines by ELISA and gene expression of apoptotic markers by real time-quantitative reverse transcription PCR (RT-qPCR). Results: It was found that vitamin D significantly decreased the levels of IL-6, TNF -α, IFN-γ and IL-10 in vitamin D treated cells of SLE patients relative to the untreated cells (P value<0.001 for each). Vtamin D3 treated cells showed that expressions of Bax (0.67±0.12) and Bcl‐2 (19.83±6.6) underwent fold change compared to that in untreated cells. It was found downregulation of Bax expression (3.5%) and upregulation of Bcl‐2 expression (1.7 fold increase) in vitamin D treated cells. Conclusion: Vitamin D is an immunomodulator agent and its administration in SLE patients may exert a good therapeutic effect. It had both inhibitory effect on cytokine levels and antiapoptotic effect in PBMCs of SLE patients.