International Journal of Endocrinology
Volume 2010 (2010), Article ID 305054, 7 pages, Clinical Study
Eleanor Yusupov, Melissa Li-Ng, Simcha Pollack, James K. Yeh, Mageda Mikhail, and John F. Aloia
Winthrop University Hospital, Bone Mineral Research Center, 222 Station Plaza North, Suite 350A, Mineola, NY 11501, USA
Received 27 March 2010; Revised 18 June 2010; Accepted 7 July 2010
Background. The role of vitamin D in the body's ability to fight influenza and URI's may be dependent on regulation of specific cytokines that participate in the host inflammatory response. The aim of this study was to test the hypothesis that vitamin D can influence intracellular signaling to regulate the production of cytokines.
Subjects and Methods. This study was a 3-month prospective placebo-controlled trial of vitamin D3 supplementation in ambulatory adults Li-Ng et al., 2009. 162 volunteers were randomized to receive either 50??g/d 2000 IU) of vitamin D3 or matching placebo. 25(OH)D and the levels of 10 different cytokines (IL-2, 4, 5, 6, 8, 10, 13, GM-CSF, IFN-?, TNF-?) were measured in the serum of participants at baseline and the final visit. There were 6 drop-outs from the active vitamin D group and 8 from the placebo group.
Results. In the active vitamin D group, we found a significant median percent decline in levels of GM-CSF (?62.9%, P<.0001), IFN-? (?38.9%, P<.0001), IL-4 (?50.8%, P=.001), IL-8 (?48.4%, P<.0001), and IL-10 (?70.4%, P<.0001). In the placebo group, there were significant declines for GM-CSF (?53.2%, P=.0007) and IFN-? (?34.4%, P=.0011). For each cytokine, there was no significant difference in the rate of decline between the two groups. 25(OH)D levels increased in the active vitamin D group from a mean of 64.3±25.4?nmol/L to 88.5±23.2?nmol/L.
Conclusions. The present study did not show that vitamin D3 supplementation changed circulating cytokine levels among healthy adults.