Effect of high-dose vitamin D supplementation on antibody titers to heat shock protein 27 in adolescent girls.

Background Although vitamin D deficiency is associated with several inflammatory conditions, there have been few studies on the effects of vitamin D supplementation on markers of oxidative stress (OS) and inflammation. The aim of the current study was to evaluate the effects of high-dose vitamin D supplementation on heat shock protein 27 antibody (anti-Hsp27) titers in adolescent girls. Methods Five hundred and fifty adolescent girls received vitamin D3 at a dose of 50,000 IU/week for 9 weeks. Demographic, clinical and biochemical markers including serum fasting blood glucose (FBG), lipid profile and anti-Hsp27 titers as well as hematological parameters including white blood cell (WBC) count and red blood cell (RBC) distribution width (RDW) were determined in all the subjects at baseline and at the end of the study. Results Serum vitamin D significantly increased from 6.4 (4.2-9.6) ng/mL to 35.6 (25.8-47.5) ng/mL (p < 0.001) following the intervention. Furthermore, serum anti-Hsp27 titers were significantly lower after the 9-week vitamin D administration period (0.22 [0.12-0.33] optical density [OD] vs. 0.19 [0.11-0.31] OD; p = 0.002). A significant correlation was found between serum anti-Hsp27 and RDW (r = 0.13, p = 0.037). The reduction in RDW values after intervention was particularly evident in subjects with the greatest increase in serum vitamin D levels. Conclusions High-dose vitamin D supplementation was found to reduce antibody titers to Hsp27. Further randomized placebo-controlled trials are warranted to determine the long-term effect of vitamin D administration on the inflammatory process especially that associated with chronic disease.