Effects of Cystamine on antioxidant activities and regulatory T cells in lupus‐prone mice

Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus ( SLE ). Despite the well‐established beneficial effects of cystamine on lupus‐prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti‐oxidant activities in NZB /W F1 mice by performing assays of Glutathione ( GSH ), 1,1‐diphenyl‐2‐ picryl‐hydrazyl ( DPPH ) and malondialdehyde thiobarbituric acid ( MDA ). In addition, investigations of the effects of cystamine on CD 4 + / CD 25 + regulatory T cells and interleukin‐6 ( IL 6)/ STAT ‐3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB /W F1 mice receiving cystamine than in those mice receiving PBS . Meanwhile, CD 4 + / CD 25 + regulatory T cells more significantly increase in NZB /W F1 mice receiving cystamine than in those mice receiving PBS , accompanied by significantly reduced IL ‐6/phosphorylated STAT ‐3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD 4 + / CD 25 + regulatory T cells in lupus‐prone mice by suppressing IL ‐6/ STAT 3 signalling.