Showing posts with label Xanthohumol. Show all posts
Showing posts with label Xanthohumol. Show all posts

Saturday, December 12, 2009

Xanthohumol may help in preventing prostate cancer....

We know that Xanthohumol is a Xanthone (phenylated chalcone or Phenylflavonoid). Xanthohumol was initially detected in an extract(series of Humulones) from Hops (Humulus lupulus) and is present in beer. This prenylated flavonoid has been shown to be a potent bioactive compound. Xanthohumol has been shown to have antiproliferative and cytotoxic effects in human cancer cell lines. It has also been displayed to inhibit diacyl glycerol acetyl transferase (DGAT) and human P450 enzymes. Xanthohumol inhibits the expression of HIF-1a and VEGF under hyposic conditions.

Higher antioxidant activity is reported for prenylchalcones than for prenyl flavanones in the Cu2+- mediated oxidation of LDL, suggesting a relation between structure and function. Also, many chalcones suppress tumor promotion more effectively than flavonoids themselves.

Quantities of xanthohumol found in Hop are to small to have any biological effects under normal consumption amounts. Some of the researchers also claims that it has got anti-HIV-1 activity too.

Now researchers from German Cancer Research Center, in Heidelberg, Germany, have come up with more interesting result, i.e., Xanthohumol may aid in preventing prostate cancer. As per the claim by the authors, the compound blocks the effects of the male hormone testosterone.

Studies to date have shown that xanthohumol blocks the action of estrogen by binding to its receptor, which may lead to prevention of breast cancer. Since testosterone receptors act similarly to that of estrogen — by binding, then stimulating hormone-dependent effects, such as gene expression and cell growth — the researchers examined whether xanthohumol might not only block the effects of estrogen, but also of the male hormone androgen. Xanthohumol prevented the receptor from translocating to the cell nucleus, thus inhibiting its potential to stimulate the secretion of PSA and other hormone-dependent effects.

The interesting part of their research is the molecular modeling results, which showed that xanthohumol directly binds to the androgen receptor structure. The researchers suggest that this compound may have beneficial effects in animals — when they measured the anti-androgenic potential of xanthohumol in a rat model, they found that although xanthohumol was not able to prevent an increase in prostate weight after testosterone treatment, it could reduce testosterone-increased seminal vesicle weight.

As per the claim by the researchers the prostate weights were not changed, xanthohumol still reduced the effects of hormone signaling, such as gene expression, measured in the prostate tissue...

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