Vitamin D Important for Colon Health

By CP Staff

A new study investigated the potential role that vitamin D plays in the development of the inflammatory bowel disorder known as Crohn\'s disease.

Vitamin D is important for optimal immune function and plays a role in stimulating the immune response against microbes and pathogens. It is the ability to maintain proper functioning of the immune system that acts as the body\'s first defense against microbial invaders. The impairment of this defense, which occurs during vitamin D deficiency, may lead to an increased inflammatory response, which may precipitate Crohn\'s disease.

In this new study, researchers evaluated the effect of vitamin D on two 2 genes: 1) the NOD2 gene, which codes for a protein released by white blood cells that activates the immune response and 2) the beta-defensin-2 gene, which codes for an antimicrobial protein also released from white blood cells. Mutations in these 2 genes have been associated with Crohn\'s disease.

The researchers found that 1,25-dihydroxyvitamin D3 stimulated these genes in white blood cells as measured by increased production of specific cytokines and antimicrobial proteins such as DEFB2/HBD2 from the beta-defensin-2 gene. This effect was not seen in white blood cells with defective NOD2 genes from Crohn\'s patients. The researchers showed that 1,25-dihydroxyvitamin D3 was able to specifically activate the NOD2 gene, which may reduce the risk of developing Crohn\'s disease.

Thus, the researchers suggested that vitamin D deficiency may play a role in the development of Crohn\'s disease via the NOD2 gene.

The study authors stated, “These studies provide strong molecular links between vitamin D deficiency and the genetics of Crohn\'s disease, a chronic incurable inflammatory bowel condition, as Crohn\'s pathogenesis is associated with attenuated NOD2 or DEFB2/HBD2 function.”

Reference:

Wang TT, Dabbas B, Laperriere D, Bitton AJ, Soualhine H, Tavera-Mendoza LE, Dionne S, Servant MJ, Bitton A, Seidman EG, Mader S, Behr MA, White JH. Direct and indirect induction by 1,25-dihydroxyvitamin D3 of the NOD2/CARD15-defensin beta2 innate immune pathway defective in Crohn disease. J Biol Chem. 2010 Jan 22;285(4):2227-31.