Vitamin D Supplementation Mediates a Shift toward Anti-Inflammatory Cytokine Response in Multiple Sclerosis

In this study, we assessed the impact of vitamin D (Vit-D) supplementation on cytokine profile in newly diagnosed drug-naïve multiple sclerosis (MS) patients.

We recruited 16 patients with incident MS; those were followed up for 12 months. Serum levels of 25-hydroxy-Vit-D were measured at recruitment and follow-up. Peripheral blood mononuclear cells were isolated from blood samples and stimulated with a mitogen in tissue culture to elicit cytokine production. Culture supernatants were tested after 4 days post-culture for levels of pro-inflammatory (TNF-α, interferon [IFN]-gamma, interleukin [IL]-6, IL-12) and anti-inflammatory cytokines (IL-4, IL-5, IL-10).

Baseline blood sample analysis revealed that patients had low Vit-D levels (16.8 [12.41-31.4] nmol/L). Thirteen patients expressed a normal intact parathyroid hormone (iPTH) (5.5 [4.2-6.9]) and were given Caltrate D twice a day; 3 patients having elevated iPTH (mean ± SD: 12.8 ± 1.5) were prescribed 50,000 IU Vit-D once weekly and Caltrate D twice daily. IFN-β1α was prescribed after a confirmed diagnosis of relapsing-remitting MS in 13 patients; 3 patients declined immunotherapy. Irrespective of immunotherapy, we observed a gradual and significant decrease in pro-inflammatory cytokine levels and a steady significant decline in ratios of several pro-inflammatory to anti-inflammatory cytokines. The patients with higher pro-inflammatory to anti-inflammatory cytokine ratios were more prone to having relapses.

Low Vit-D levels and elevated pro-inflammatory cytokines in drug-naïve MS patients suggest a potential immune-pathogenic role for hypovitaminosis D in MS development. Vit-D supplementation may exert protective effects by modulating the immune-inflammatory response, emphasizing its therapeutic importance in MS management.