de la Fuente AG, Errea O, van Wijngaarden P, Gonzalez GA, Kerninon C, Jarjour AA, Lewis HJ, Jones CA, Nait-Oumesmar B, Zhao C, Huang JK, Ffrench-Constant C, Franklin RJ.Vitamin D receptor–retinoid X receptor heterodimer signaling regulates oligodendrocyte progenitor cell differentiationJ Cell Biol. 2015 Dec 7;211(5):975-985
The mechanisms regulating differentiation of oligodendrocyte (OLG) progenitor cells (OPCs) into mature OLGs are key to understanding myelination and remyelination. Signaling via the retinoid X receptor γ (RXR-γ) has been shown to be a positive regulator of OPC differentiation. However, the nuclear receptor (NR) binding partner of RXR-γ has not been established. In this study we show that RXR-γ binds to several NRs in OPCs and OLGs, one of which is vitamin D receptor (VDR). Using pharmacological and knockdown approaches we show that RXR–VDR signaling induces OPC differentiation and that VDR agonist vitamin D enhances OPC differentiation. We also show expression of VDR in OLG lineage cells in multiple sclerosis. Our data reveal a role for vitamin D in the regenerative component of demyelinating disease and identify a new target for remyelination medicines.
New work from Prof ffffffffrench-constant and Franklinstein show that vitamin D can now affect oligodendrocyte function. (see picture myelin green, nerves red). Many many genes have gene response elements that respond to vitamin D and the receptor that they hope will be the switch factor for myelin repair is called RXR.
They find that this too has a vitamin D receptor response element, so vitamin D aid recovery and show that this can aid remyelination. This is implied here and I guess the data will be out eventually.
They were using rat cells and these beasties live in the dark and so no quite human however importantly, the system was really pushed to show this effect. In the original experiment when the precursor cells were treated with vitamin D there was no difference in proliferation, differentiation or survival.
What they had to do was first ensure that there was no vitamin D response and then add it. Then they showed it stopped vitamin D proliferation but it enhanced differentiation.
However, ask yourself this! Many of you have done the experiment already. There are loads of you out there who are taking ProfGs advice and scoffing vitamin D tablets, as we have no sun in Northern Europe at the minute.
Did Vitamin D supplementation make a dramatic impact to your symptoms that should have been repairing in droves? If the simple belief was correct? Do you feel it happening when out in the sun maybe the best treatment for MS is a deck chair on the promenade. I suspect we know the answer to this experiment?
I expect that more than just VD will be needed to get repair but with the X (RXR) factor being stimulated too. However after Vitamin D did you feel it happen? Let's have your views?
Irrespective of this make sure you are vitamin replete to ensure good bone health and who knows it can be helping the myelin.