Vitamin D Stimulates Androgen Receptor Expression
By Rob Clarke Driven Sports
I realize that you’re probably sick to the back teeth of my discussions of vitamin D, but as science progresses more findings are uncovered. The latest is the involvement of vitamin D in muscle regeneration through two quite novel pathways.
Every year the Endocrine Society holds a meeting and expo where researchers present their work. The latest was held in Boston between June 4th and 7th, so this is very new research. In fact, it has yet to be published.
The research they presented at the meeting looked into the effects of vitamin D and Nandrolone on muscle regeneration. You should all be well aware what vitamin D is, but those of you confused about nandrolone need only know that it is an anabolic steroid. Several professional sports athletes have tested positive for this in the past decades, although due to stricter testing in sports it is becoming much less common. No doubt your local gym has several guys fully aware of the stuff if you tell them it goes by the street name “Deca”.
It has long been believed that every cell in the body has a vitamin D receptor. Interestingly though, fairly recent research determined that muscle cells lack the vitamin D receptor, and yet it has also been firmly shown that vitamin D can fortify muscles. While only one study indicates this lack of the vitamin D receptor, this is a discrepancy that was somewhat confusing until scientists working for Dutch company OrgaNext Research presented their findings last month. The discovery is that vitamin D stimulates the expression of the androgen receptor on muscle cells.
The androgen receptor (the protein model is illustrated here) is like a docking station on the cell that androgens like testosterone fit into. Upon doing this, several complex processes are kick-started, but the fundamental product is that protein synthesis is stimulated within the cell nucleus. Protein synthesis IS muscle building.
The scientists also uncovered that both vitamin D and nandrolone could – individually and in combination - increase expression of the vitamin D receptor in muscle cells. When in combination this effect was synergistic. Clearly there is more research required to determine whether muscles do or do not have vitamin D receptors.
But that is not all. The scientists looked into the effects that nandrolone and vitamin D have on satellite cell proliferation. Satellite cells, as you may recall from the stem cell article, are the cells that fuse themselves into existing muscle fibers for repair and growth. The satellite cell pool is far from abundant and takes time to replenish once they have been activated and used. This is why building muscle takes time and consistency.
The researchers found that the combination of nandrolone and vitamin D triggered the proliferation of satellite cells synergistically. When tested alone vitamin D excelled at this in older muscle cells. In other words, if you increase the level of androgens in your body it is a great idea to ensure you are not vitamin D deficient. It was no mistake that vitamin D was included in Activate Xtreme™. While on this tangent, vitamin D not only has aromatase inhibiting properties itself, it also augments the ability of other aromatase inhibitors. It is no mistake why the stack of Activate Xtreme™ and Triazole™ (featuring the revolutionary pZole™) has become to increasingly popular.
So vitamin D not only ensures proper testosterone synthesis and reduces estrogen where we ideally want it reduced, it also boosts the sites of action for testosterone. Amazingly, there are still so many people deficient in this vitamin – even those in hot climates! If these people take an active interest in their health and their bodies they are truly selling themselves short. I would hope that readers of the Driven Blog are convinced enough by now to be actively getting outside more or supplementing with vitamin D (ideally through Activate Xtreme™!)
Source: Helenius Jan Kloosterboer, PhD, Marjanne Prins and Reiner Class, PhD. Combinatorial Effects of Nandrolone and Vitamin D3 on Human Skeletal Muscle Cell Proliferation. Endocr Rev, Vol. 32 (03_MeetingAbstracts): P1-210