I came across an interesting article this week titled "Sun exposure and vitamin D are independent risk factors for CNS demyelination." It allowed for the examination of past sun exposure before the onset of multiple sclerosis. The study's participants all had experienced a first clinical diagnosis of CNS demyelination, which was abbreviated FDE for first demyelination event. The sun exposure measurements included questionnaires where participants recorded the amount of leisure time spent in the sun for different periods of life, from age 6 to current age. Participants provided blood samples for DNA analysis of vitamin D binding protein alleles and to determine baseline vitamin D levels. In order to analyze the ambient UV exposure over each person's life, the researchers estimated the latitude and longitude of the person's place of residence and calculated the UV dose over the relevant period.
It was found that higher self-reported time in the sun in the 3 years prior to the questionnaire and increasing leisure-time UV dose were associated with reduced FDE risk. FDE cases had lower vitamin D levels than matched controls, and FDE risk decreased with increasing vitamin D levels. Also, fair skin was associated with increased FDE risk.Vitamin D functions by inhibiting T cell proliferation and decreasing the production of the Th1 cytokines IL-2, IFN-gamma, and TNF-alpha. It may also be a physiological regulator of T-cell development. Because of these anti auto-immune effects, vitamin D is one of many potential new therapies for multiple sclerosis, which is definitely a step in the right direction.
http://ovidsp.tx.ovid.com.ezproxy1.library.arizona.edu/sp-3.8.1a/ovidweb.cgi?WebLinkFrameset=1&S=EGDLFPAIANDDEJHJNCOKFHFBMBGEAA00&returnUrl=ovidweb.cgi%3f%26TOC%3djb.search.27%257c1%257c50%26FORMAT%3dtoc%26FIELDS%3dTOC%26S%3dEGDLFPAIANDDEJHJNCOKFHFBMBGEAA00&directlink=http%3a%2f%2fgraphics.tx.ovid.com%2fovftpdfs%2fFPDDNCFBFHHJAN00%2ffs047%2fovft%2flive%2fgv024%2f00006114%2f00006114-201102080-00009.pdf&filename=Sun+exposure+and+vitamin+D+are+independent+risk+factors+for+CNS+demyelination+%28CME%29.&link_from=jb.search.27|1&pdf_key=B&pdf_index=jb.search.27
http://ebm.rsmjournals.com/content/223/3/230.full
It is interesting that something as simple as vitamin D can potentially lower our risk for developing MS. Since vitamin D is synthesized by our bodies by simply being exposed to sunlight it isn't very hard to get. I found this other study that showed areas close to the equator have pretty much no cases of MS, as well as higher altitudes. Since these areas are much more exposed to sunlight it goes along with the results in this study showing that people who are more exposed to the sun have higher vitamin D levels and lower risk of FDE.
ReplyDeletehttp://ebm.rsmjournals.com/content/216/1/21.short
ReplyDeleteI found this article interesting as well. When I thought of vitamin D and sun exposure, all I could think about was UV rays. With UV rays contributing to skin cancer, (although I'm not entirely sure on this part and its mechanisms) it can distort DNA. So, I was thinking along the lines of which the sun exposure can change the DNA so that somehow, the myelination does not occur. I thought that this was where the article was heading, but was surprised when it headed towards how vitamin D increases which is anti-inflammatory (makes sense though since this is a inflammation class). But because there is skin cancer risks, if this was to be used as treatment or preventative measures, it might be better to eat the vitamins instead of sit out in the sun for a long time.
ReplyDeleteI also found this article very interesting because I wouldn't think that something that we obtain from sitting out in the sun (vitamin D) can help lower the risk of getting multiple sclerosis. It made me a little excited because I grew up here in Arizona and am always out in the sun so I should be getting a lot of vitamin D and have hopefully decreased my risk of getting MS.
ReplyDeleteOne problem I think this article may cause is that people may start thinking they need to go sit out in the sun more without sunblock so they can get the most UV rays. The sun can cause other problems such as skin cancer. So, even though this sounds like it could be a great treatment/ preventative measure, people still need to be careful when dealing with the sun.
I'm glad you found more information between sun exposure, vitamin D, and MS, because it was mentioned briefly in my neuroscience class and I was interested to learn more! It's interesting to hear how getting some sun exposure can be a beneficial treatment since we're mostly told to stay out of the sun. In my neuroscience class my teacher mentioned that living in a more tropical/closer the equator climate lowered your risk for MS, but that it was only effective if you lived in that climate for about the first 15 years of your life. I think this is because of the rate at which your neurons become myelinated, which is early on in life, so it's good to have that exposure to Vitamin D during that period of your life. Any other theories?
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