Authors: Courtney Johnson
A double-blind, single-center randomized pilot study carried out at Johns Hopkins University (MD, USA) has demonstrated that high-dose vitamin D3 (cholecalciferol) supplementation can result in a reduction in inflammatory T cells that are associated with disease severity in multiple sclerosis (MS). The findings were published recently in the journal Neurology.
In MS, there is a correlation between low levels of vitamin D and greater disability and disease activity. Low levels of vitamin D in the blood are also linked to a higher risk of developing the condition.
The current study examined the safety and immunologic effects of cholecalciferol administration for MS patients. A cohort of 40 individuals with relapsing–remitting MS were included in the 6 month study. Patients received a dose of either 10,400 IU or 800 IU of cholecalciferol daily, both above the current recommended daily allowance of 600 IU. Patients with severe vitamin D3 deficiency were not included in study. Blood tests were carried out at baseline and then at 3 and 6 months to measure vitamin D levels and T-cell response.
Patients in the high-dose group achieved larger increases in levels of vitamin D in the blood in comparison to the low-dose group, which were associated with a reduction in the inflammatory T-cell response.
Researchers proposed a target optimal level of 40–60 ng/ml of vitamin D in the blood for individuals with MS. Only participants in the high-dose group achieved these levels in the blood. However, the optimal dose for MS patients is yet to be determined.
In the high-dose group, there was a noticeable reduction in the percentage of inflammatory T cells (specifically IL-17+CD4+ and CD161+CD4+) that are normally associated with MS severity. Once a difference of 18ng/ml of vitamin D in the blood was reached above baseline values, every further increase in 5ng/ml led to a 1% reduction in IL-17+CD4+ T cells in the blood.
Observed side-effects were categorized as minor and did not differ between the high-dose group and low-dose group. One person from each dosing group relapsed.
With these preliminary findings suggesting in vivo pleiotropic immunomodulatory effects for high-dose cholecalciferol supplementation in MS, further studies could lead to promising avenues of research for disease treatment.
“These results are exciting, as vitamin D has the potential to be an inexpensive, safe and convenient treatment for people with MS,” commented Peter Calabresi (Johns Hopkins University). “More research is needed to confirm these findings with larger groups of people and to help us understand the mechanisms for these effects, but the results are promising.”
“We hope that these changes in inflammatory T cell responses translate to a reduced severity of disease,” remarked Calabresi. “Other clinical trials are underway to determine if that is the case.”
Sources: Johns Hopkins University Press Release; Sotirchos ES, Bhargava P, Eckstein C et al. Safety and immunologic effects of high- vs low-dose cholecalciferol in multiple sclerosis. Neurology doi:10.1212/WNL.0000000000002316 (2015) (Epub ahead of print).