[Vince001]

Twee stukjes over vitamine E Succinate. Een beetje een naar onderwerp, prostaatkanker, maar vitamine E Succinate schijnt ook de werking van androgene receptoren te verminderen...

VIATMIN E SUCCINATE DOWN REGULATES ANDROGEN ACTIVITY

Out of prostate research comes some interesting findings about Vitamin E Succinate that could have possible implications for male pattern loss, which is largely mediated by the same hormonal factors implicated in prostate enlargement and prostate cancer. It was only the succinate version of vitamin E that produced these specific effects, which is inexpensive and widely available. A study published in the May 28 2002 issue of the Proceedings of the National Academy of Sciences(http://www.pnas.org/ ) has revealed previously unknown mechanisms of action for vitamin E succinate against prostate cancer. Vitamin E had been associated with a lower incidence of prostate cancer in epidemiologic studies and the succinate form of the vitamin has been shown to inhibit cancer growth in several studies.

The University of Rochester researchers used an androgen-dependent human prostate cancer cell line to find out how vitamin E succinate prevents and combats cancer. In one experiment, vitamin E succinate was compared to the antiandrogen drug flutamide. While the addition of flutamide largely failed to combat growth stimulated by the addition of the androgen dihydrotestosterone (DHT), vitamin E succinate proved to be successful. However, when both compounds were added, a further repressing of DHT-mediated cell growth was observed. When tumor cells were replaced with cell cultures from normal prostate tissue, the same amount of vitamin E succinate only slightly inhibited cell growth, suggesting that the vitamin may selectively inhibit tumor cells that are androgen sensitive.

In another experiment that sought to determine the effect of vitamin E succinate on prostate specific antigen (PSA), a marker for prostate cancer, PSA expression was induced by the addition of DHT to the cell culture. When vitamin E was added, intracellular and secreted levels of PSA expression were repressed. This occurred together with down-regulation of androgen receptor protein levels. The androgen receptor is required for the initiation and progression of prostate cancer and Male Pattern Hair Loss. The authors write that vitamin E succinate may suppress the growth of prostate cancer and the expression of PSA "by inhibiting androgen receptor expression at both the transcription and translation levels." An oral dose of 800 i.u.'s would be appropriate to produce these effects.

Bron:http://www.hairloss-research.org

Vitamine E maakt prostaat doof voor

Vitamine E vermindert het aantal androgeenreceptoren in de prostaat. Dat schrijven onderzoekers van de University of Rochester in de Proceedings of the National Academy of Sciences van 28 mei. De vitamine schroeft ook de aanmaak van het 'prostaatkankereiwit' PSA terug. Dat betekent dat vitamine E de prostaat beschermt tegen kanker.

De wetenschappers bestudeerden prostaatkankercellen in een reageerbuis. Tot hun verbazing bleken E-vitamines effectiever kankerremmers dan het anti-androgeen hydroxyflutamide. Flutamide doet met androgeenreceptoren wat nolvadex met eastradiolreceptoren doet: het gaat wel een koppeling aan maar start daarbij geen reacties op.

De aanmaak van PSA liep terug met 90 procent, het aantal cellen verminderde met 30 - en soms zelfs met 90 procent.

De onderzoekers benadrukken dat niet alle varianten van vitamine E even goed werken. Zijzelf boekten de beste resultaten met alpha-tocopheryl succinaat.

Het verdere onderzoek gaat twee sporen volgen: de combinatie van vitamine E en de klassieke anti-androgenen, en de combinatie vitamine D en vitamine E.

Uit onderzoek, waarbij onderzoekers kijken naar het gevolg van voeding op de gezondheid bij grote groepen mensen, was al gebleken dat mannen met veel vitamine E in hun dieet minder vaak prostaatkanker krijgen. Maar de theorie daarachter was altijd dat de anti-oxidant vitamine E vrije radicalen onschadelijk maakt.

Uit deze studie blijkt echter dat vitamine E nog veel meer doet: het blokkeert in de prostaat de aanmaak van twee eiwitten die nodig zijn om kankercellen te laten functioneren.

1. Tom Rickey. Study Shows Cancer Cells Are Vulnerable In New Ways. UniSci, 29-5-2002. [Link]
2. Zhang Y, Ni J, Messing EM, Chang E, Yang CR, Yeh S. Vitamin E succinate inhibits the function of androgen receptor and the expression of prostate-specific antigen in prostate cancer cells. Proc Natl Acad Sci U S A 2002 May 28;99(11):7408-13. [PubMed]

Bron:http://www.ergogenics.org