The Modulatory Effects of Vitamin D on the Expression of IL-12 and TGF-β in the Spinal Cord and Serum of Mice with Experimental Autoimmune Encephalomyelitis

Abstract

KEYWORDS ABSTRACTExperimental Autoimmune Encephalomyelitis Vitamin D IL-12 TGF-β Background & objective:The immunoregulatory effects of transforming growth factor (TGF)-βand interleukin-12 (IL-12) and immunomodulatory actions of vitamin D (VD) were reported in several studies. This study aims to evaluate VD effects on IL-12 and TGF-β expression in experimental autoimmune encephalomyelitis (EAE).Methods: EAE was induced in three groups of C57BL/6 mice by immunization with MOG and administered intra-peritoneally 200 ngVD, PBS or olive oil (OO) from day +3 to +30. One group was also considered as healthy control group. At day 31, cytokines expression in the spinal cord and their serum levels were determined using real time-PCR and ELISA, respectively.Results: IL-12 gene expression and its serum levels in PBS-injected-or OOadministrated EAE groups were significantly higher than healthy group. IL-12 gene expression in EAE group treated with VD was significantly decreased compared to PBS-injected-or OO-administrated EAE groups (P<0.001 and P<0.02, respectively). Serum IL-12 levels were significantly reduced in VD-treated EAE mice compared to PBS-injected-or OO-administrated EAE groups (P<0.004 and P<0.05, respectively). No significant difference was observed between PBS-injected-EAE, OOadministrated EAE and healthy groups regarding the expression of TGF-β. In EAE mice treated with VD, TGF-β expression was significantly higher than healthy group and PBS-injected EAE mice (P<0.01 and P<0.04, respectively). VD-treated EAE group had also higher serum TGF-β levels than PBS-injected-, OO-administrated and healthy groups (P<0.05).Conclusion: VD modulates the expression of IL-12 and TGF-β in spinal cord and serum of EAE mice. Article Info

MiRNA-29b modulates neuroinflammation by targeting T-bet in Experimental Autoimmune Encephalomyelitis mice treated with vitamins A and D

“…However, long-term usage of these drugs might have undesirable effects. Environmental factors, including micronutrients such as vitamins, have been shown to in uence the differentiation of immune cells and production of cytokines in both normal and disease settings [41][42][43].Using nutrients with the ability to tip the balance towards the protective elements might represent another therapeutic option with potentially fewer side effects [44]. In this study, we investigated the effects of vitamins A, D and their combination on Th1 cell differentiation as well as the expression of Th1-speci c transcription factor, T-bet and its regulating miRNAs.…”

“…Numerous studied have emphasized the importance of miRNAs in regulating T cell differentiation [52]. Vitamin D can increase miRNA expression by binding the VDR/RXR heterodimer to VDREs in the miRNA gene promoter (44). In the current study, we provided evidence that miR-29a/b-3p are involved in T cell differentiation and vitamins A and D might control T cell differentiation by regulating the expression of miR-29a/b that target a T cell-speci c transcription factor.…”