Environmental factors in multiple sclerosis.
Presse Med. 2015 Mar 2. pii: S0755-4982(15)00064-0. doi: 10.1016/j.lpm.2015.01.001. [Epub ahead of print]
Pantazou V1, Schluep M1, Du Pasquier R2.
1CHUV, University Hospital of Lausanne, Department of Clinical Neurosciences, Service of Neurology, 1011 Lausanne, Switzerland.
2CHUV, University Hospital of Lausanne, Department of Clinical Neurosciences, Service of Neurology, 1011 Lausanne, Switzerland; CHUV, University Hospital of Lausanne, Centre of Research in Clinical Neurosciences, Laboratory of Neuroimmunology, 1011 Lausanne, Switzerland. Electronic address: renaud.du-pasquier at chuv.ch.
Although multiple sclerosis (MS) is recognized as a disorder involving the immune system, the interplay of environmental factors and individual genetic susceptibility seems to influence MS onset and clinical expression, as well as therapeutic responsiveness. Multiple human epidemiological and animal model studies have evaluated the effect of different environmental factors, such as viral infections, vitamin intake, sun exposure, or still dietary and life habits on MS prevalence.
Previous Epstein-Barr virus infection, especially if this infection occurs in late childhood, and lack of vitamin D (VitD) currently appear to be the most robust environmental factors for the risk of MS, at least from an epidemiological standpoint.
Ultraviolet radiation (UVR) activates VitD production but there are also some elements supporting the fact that insufficient UVR exposure during childhood may represent a VitD-independent risk factor of MS development, as well as negative effect on the clinical and radiological course of MS.
Recently, there has been a growing interest in the gut-brain axis, a bidirectional neuro-hormonal communication system between the intestinal microbiota and the central nervous system (CNS). Indeed, components of the intestinal microbiota may be pro-inflammatory, promote the migration of immune cells into the CNS, and thus be a key parameter for the development of autoimmune disorders such as MS. Interestingly most environmental factors seem to play a role during childhood. Thus, if childhood is the most fragile period to develop MS later in life, preventive measures should be applied early in life.
For example, adopting a diet enriched in VitD, playing outdoor and avoiding passive smoking would be extremely simple measures of primary prevention for public health strategies. However, these hypotheses need to be confirmed by prospective evaluations, which are obviously difficult to conduct.
In addition, it remains to be determined whether and how VitD supplementation in adult life would be useful in alleviating the course of MS, once this disease has already started. A better knowledge of the influence of various environmental stimuli on MS risk and course would certainly allow the development of add-on therapies or measures in parallel to the immunotherapies currently used in MS.
Copyright © 2015 Elsevier Masson SAS. All rights reserved.
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See also VitaminDWiki
- Overview MS and vitamin D
- 1000 IU per kg Vitamin D for autoimmune diseases – Coimbra Aug 2013
- Antibiotics and Vitamin D are associated with many of the same diseases MS is one of many related diseases
- Exploring gut microbes in Human health and disease: pushing the envelope - Aug 2014
- Vitamin D, immunity and microbiome – Dec 2014
- The articles in both MS and Infant-Child are:
- Brain and Vitamin D - many studies
- Multiple Sclerosis risk reduced 30 percent for additional 10 ng of vitamin D at birth – Jan 2017
- Multiple sclerosis in children – low vitamin D is a potential factor – Aug 2016
- Hypothesis – Multiple Sclerosis risk increases with low UV, viral infections, and antibiotics in childhood – March 2015
- MS relapse rate for children was 34% less for every extra 10 ng/ml of vit D
- The articles in both MS and UV are:
- Multiple Sclerosis treated equally by UVB and weekly 50,000 IU of Vitamin D – RCT July 2023
- Mutiple Sclerosis half as likely in children spending 30 to 60 minutes per day in the sun – Dec 2021
- Sun reduces risk of Multiple Sclerosis via both Vitamin D and another way – Dec 2019
- UV helped EAE mice (MS) designed to not respond to Vitamin D – Oct 2019
- Multiple Sclerosis 2X more likely if low winter UV – June 2018
- Multiple Sclerosis half as likely if get plenty of sunshine (not a news item) – March 2018
- Clinically Isolated Syndrome progresses to Multiple Sclerosis, unless UVB treatments – RCT Dec 2017
- Vitamin D and Sun conference – Germany June 2017
- Multiple Sclerosis suppressed by an Ultraviolet wavelength not associated with Vitamin D (mice) – Nov 2016
- Multiple Sclerosis helped by UV – possibly via cytokines, etc. – Oct 2015
- Hypothesis – Multiple Sclerosis risk increases with low UV, viral infections, and antibiotics in childhood – March 2015
- How UVB reduces autoimmune diseases such as Multiple Sclerosis – April 2014
- UV decreases Multiple Sclerosis via cis-urocanic acid (and via vitamin D) – June 2013
- MS prevention by UV is 2X better than prevention by vitamin D levels – Jan 2012
- There is more in UV than vitamin D which suppresses MS in mice – April 2010
- UV produces more than vitamin D – Aug 2011
- Lack of UV 20X more associated with MS than any other variable – Dec 2010
- Hypothesis - more in sunshine than vitamin D to reduce MS – Feb 2010
- MS UV and Vitamin D – 2009
- Lack of UV increased offspring MS - April 2010
- Mouse MS: UVB but not Vitamin D reduced incidence - April 2010