RESUMEN
BACKGROUND AND PURPOSE: The aim of this study was to investigate the expression levels of vitamin D receptor (VDR) and NF-κB mRNAs in vitamin D (VD) supplemented multiple sclerosis (MS) patients. METHODS: RRMS patients received 50,000 IU vitamin D3/week as an intra-muscular injection for 2 months. Blood samples were obtained from 30 MS patients before and after VD supplementation and 32 healthy individuals, and then VDR and NF-κB mRNA levels were measured by real time PCR method and analyzed with independent and paired t-tests. Moreover, some correlations were performed between the expression levels of selected genes and some clinical features of MS and control groups. RESULTS: Surprisingly, the expression level of VDR mRNA significantly decreased after 2 months supplementation with VD in our selected patients and in contrast, the level of serum 25(OH) D increased after supplementation. Although, we didn't find any significant difference in the expression level of NF-κB gene before and after treatment with VD, its expression significantly decreased in untreated MS cases compared with healthy controls. CONCLUSION: In conclusion, we found some new evidences from the molecular mechanism of vitamin D effectiveness in MS treatment. Also, we need more functional studies to find the effect of VD on the expression level of VDR mRNA.