Effect of vitamin D supplementation on cathelicidin, IFN-γ, IL-4 and Th1/Th2 transcription factors in young healthy females.

OBJECTIVES: We assessed the effect of cholecalciferol and calcium supplementation on mRNA expression of cathelicidin (LL-37), Th1 and Th2 cytokines and their transcription factors in the peripheral blood mononuclear cells (PBMCs) in healthy females with vitamin D deficiency (VDD). SUBJECTS/METHODS: Subjects included 131 females with biochemical VDD randomized to receive (a) oral cholecalciferol (60,000 IU/week for 8 weeks followed by 60,000 IU/fortnight (b) calcium (elemental calcium 500 mg twice/day) (c), dual supplementation and (d) placebo for 6 months. The mRNA expression of cathelicidin, Th1 (IFN-γ) and Th2 (IL-4 and its antagonist-IL-4δ2) cytokines and their transcription factors (T-bet, STAT4, GATA-3, STAT6) were measured in the PBMC by real-time PCR before and after intervention. RESULTS: Cholecalciferol-supplemented groups showed significant rise of mean serum 25(OH)D (30.6 ± 7.51 and 28.6 ± 8.41 ng/ml). The expression of LL-37, IFN-γ, IL-4, IL-4δ2 and transcription factors were comparable in the four groups at baseline. Despite significant increase in mean serum 25(OH)D in the cholecalciferol-supplemented groups, their mean mRNA transcripts of LL-37, IFN-γ, IL-4, transcription factors and their IFN-γ/IL-4 and T-bet/GATA-3 ratios were similar to that of calcium and placebo groups. CONCLUSIONS: Six months of cholecalciferol/calcium supplementation in young females with VDD do not lead to significant alteration in mRNA expression of LL-37, Th1/Th2 cytokines and their transcription factors.