Page 1 of 1
Modulation of ms by sunlight exposure: cis-urocanic acid
Posted: Mon Jul 01, 2013 11:18 am
by leonardo
Modulation of multiple sclerosis by sunlight exposure: Role of cis-urocanic acid.
Correale J, Farez MF.
Source
Department of Neurology, Institute for Neurological Research Dr. Raúl Carrea, FLENI, Buenos Aires, Argentina. Electronic address:
jcorreale@fleni.org.ar.
Abstract
The role of cis-urocanic acid (UCA) as a UV-mediated immunomodulator in MS patients was investigated. Plasma levels of cis-UCA were significantly lower in MS patients compared to controls. Stimulation of MBP- and MOG-specific T cells in the presence of cis-UCA, significantly increased IL-10, and inhibited IFN-γ production. PBMCs cultured in the presence of cis-UCA increased CD4+CD25+FoxP3+ regulatory T cell percentages. Dendritic cells cultured in the presence of cis-UCA significantly reduced Ag presentation capacity. Finally, cis-UCA activated the 5-HT2A receptor, inducing the increase in phosphorylated forms of ERK 1/2 and JNK2. Thus, in addition to vitamin D, cis-UCA also appears to be an additional UV-mediated immunomodulator.
Copyright © 2013 Elsevier B.V. All rights reserved.
PMID: 23800457 [PubMed - as supplied by publisher]
any comments on this?
Re: Modulation of ms by sunlight exposure: cis-urocanic acid
Posted: Mon Jul 01, 2013 12:08 pm
by jimmylegs
interesting find
found this..
Modulation of the immune system by UV radiation: more than just the effects of vitamin D? (2011)
http://www.nature.com/nri/journal/v11/n ... i3045.html
not sure what article this item connects readers up to, but here it is anyway:
Sunlight exposure and sun sensitivity
http://www.thisisms.com/forum/general-d ... 18003.html
and of course the recently discussed
Sun exposure promotes nitric oxide release
http://www.thisisms.com/forum/chronic-c ... 22308.html
Re: Modulation of ms by sunlight exposure: cis-urocanic acid
Posted: Mon Jul 01, 2013 12:13 pm
by jimmylegs
http://en.wikipedia.org/wiki/Urocanic_acid
Urocanic acid is an intermediate in the catabolism of L-histidine.
In the liver, urocanic acid is transformed by urocanate hydratase (or urocanase) to 4-imidazolone-5-propionic acid and subsequently to glutamic acid.
Urocanic acid was detected in animal sweat and skin where, among other possible functions, it acts as an endogenous sunscreen or photoprotectant against UVB-induced DNA damage. Urocanic acid is found predominantly in the stratum corneum of the skin and it is likely that most of it is derived from filaggrin catabolism (a histidine-rich protein). When exposed to UVB irradiation, trans-urocanic acid is converted in vitro and in vivo to the cis isomer. The cis form is known to activate regulatory T cells.