Monday, February 27, 2012

New path discovered by which vitamin D reduces inflammation

Scientists have identified a new path by which vitamin D reduces inflammation.

According to a group led by Elena Goleva at National Jewish Health Center in Denver, vitamin D binds to a receptor in monocytes, a type of white blood cell. The receptor then binds to DNA in the cells and directs the cells to make more of an enzyme that shuts down inflammatory signaling.

The researchers found that vitamin D at or above a concentration of 30 nanograms per milliliter was enough to do the job. 30 ng/ml is a widely accepted lower limit for vitamin D in blood serum. (I recently had my own vitamin D level assayed and found it was 32 ng/ml.)

The research was published in the Journal of Immunology. [paper] [media summary] The authors say that vitamin D not only is important in maintaining calcium levels and bone health, but also plays an important role in the immune response.

That’s what I’ve found in my reading, although there’s also a lot of people on the internet who would like you to believe that taking vitamin D supplements—sometimes to an extreme degree—is a good idea for your health and in particular for relieving eczema. I remain wary. If vitamin D is so important then you need to maintain a proper level, not overdose yourself.  All drugs are toxic when ingested beyond ranges established to be safe in clinical trials.

What I like about this paper is that the authors have gone out of their way to conduct their experiments in an environment that is similar to the human body, as far as concentrations of various substances go (including vitamin D). They also used monocytes taken from human donors instead of cells from some purified, genetically altered strain, as is so often the case with cell biologists dabbling in medical applications. So their results mean something to you and me.

One question that I do have is whether the same kind of inflammation studied here—caused by LPS, a bacterial molecule that triggers an anti-infection response—is at work in chronic eczema. Is there one major inflammatory response, or are there several?

1 comment:

  1. I emailed Elena Goleva to let her know I was interested in her research. Regarding the connection between vitamin D and eczema, she writes

    "Remember that vitamin D is a strong inducer of LL-37 production (a potent antimicrobial peptide) by keratinocytes. The former mechanism is more applicable to skin protection from Staphylococcal infection in eczema."