Studying the expression of genes that are dependent on vitamin D makes it possible to identify individuals who will benefit from vitamin D supplementation, shows a University of Eastern Finland study published recently in PLoS One.
Population-based studies have shown that vitamin D deficiency may increase the risk for chronic diseases and weaken the body's immune system. In the present study carried out at the University of Eastern Finland, Kuopio, the study participants were given a daily dose of either 40 or 80 micrograms of vitamin D, or a placebo, over a course of 5 months during Finnish winter. The results showed that the expression of vitamin D dependent genes in adipose tissue and monocytes, i.e. white blood cells, correlated only in half of the study participants with their vitamin D concentrations in the blood.
The researchers concluded that persons whose expression of the CD14 and thrombomodulin genes was not altered as a result of vitamin D supplementation already had a sufficiently high serum vitamin D concentration or their utilization of vitamin D was disturbed, which calls for further study. The researchers believe that studying the expression of vitamin D dependent genes in tissues is a novel way to identify individuals who might benefit from long-term vitamin D supplementation. This observation is further supported by the fact that studying alterations in the expression of genes also made it possible to identify persons whose levels of interleukin 6, an inflammation marker, were reduced as their serum vitamin D levels increased.