Group items tagged

Melatonin downregulates aromatase expression through COX2

Study finds that inhibition of aromatase activity in diabetic male rats provided renal protection. There has been debate about the effects of testosterone therapy on the renal system. However, I propose that aromatase activity and conversion to estrogen is the negative effects of Testosterone. Other than over dosing men. Though this is a rat study, this study does support the theory.

very interesting study in rats.  LH induced a dose-dependent increase in testicular estrogen production through aromatase activity.  Yes, LH stimulates the leydig cells to produce testosterone, but there is a point at which LH will actually increase aromatase activity and thus estrogen production at the testicular level.

Injectable testosterone shown to increase Estradiol production and negatively influence the E2:T ratio in older, obese men.  This is no surprise as age and obesity are known to increase aromatase activity.  I am really surprised that no discussion of aromatase inhibition was discussed.

good review of aromatase in men.

aromatase inhibition with anastrozole, in this study, resulted in impaired flow mediated dilation.  No resultant change in inflammatory markers were seen.  Again, my problem with this study is the use of serum for the hormone evaluation.  I would bet not enough aromatase inhibition was provided.

high aromatase activity and conversion of testosterone to estrogen conversion plays a role in lupus and RA.  Inflammatory cytokines are shown to increase aromatase activity.

this study finds aromatase presence in the stroma of the prostate and not the epithelium of the prostate.  This would support the thought that increased aromatase activity and thus conversion of Testosterone to Estradiol in the prostate stroma contributes to BPH.

Great article!!  Nice discussion of the complexity of hormones.  Women on aromatase inhibitors can make estrogen from Testosterone.  This is important with estrogen sensitive cancer as in breast cancer.  This will occur via alternative pathways: Testosterone to DHT via 5 alpha reductase and then DHT to 3 beta androstanediol via 3 beta HSD.  3 beta androstanediol is a male hormone metabolite that binds to estrogen receptors.  The affinity is less than Estradiol, but appears to have a higher affinity for ER beta over ER alpha. 

Study finds that Testosterone with or with the aromatase inhibitor anastrazole as a pellet reduced breast cancer risk.  This conclusion should be taken with caution.  It is well know that abnormal breast tissue, breast cancer, highly expresses aromatase activity which would increase Testosterone to estradiol production.  This would feed any growing tumor.  But, this study finds protection.  The failure of this study is the measurement of hormone levels.

Much has been debated about the effects of androgens on prostate growth.  However, growing evidence is emerging that prostatic aromatase activity is responsible.  This study finds that high aromatase activity and thus Testosterone to Estradiol conversion in the prostate stroma is responsible for the pathogenesis of BPH.

High aromatase activity and ER alpha expression/signaling associated with prostate disease.

Mouse study, but aromatase activity and ER alpha required for atherosclerosis in male mice.

animal model, but Bisphenol A shown to increase aromatase production.  This aids the decreased T:E2 ratio that is commonly found in prostate disease.  So, BPA is a xenoestrogen.  BPA is an androgen receptor antagonist and BPA increases aromatase activity.  

Again, Testosterone and here Estradiol are merely there for libido and sex.  What tunnel vision?!  What about hsCRP?  What about fibrinogen?  What about IL-1beta?  What about TNF-alpha?  These inflammatory cytokines have all been reported to elevate as a result of estrogen production in men.   And PSA?  No mention of it here.   This linear, tunnel vision thinking on hormones has got to stop! The study points out that all clients were using AIs and SERMs irregardless of whether they had elevated estrogens or not.  That is not a well designed study.  One group should have had AI's if elevated estrogens were present and another group should not--this would compare the effects of aromatase activity.  Second, this was simply a retrospective chart review.  Third, a 50% conversion of 34,000 + men is very high when you look at the literature.  Fourth, they point to gynecomastia as a means of negative?  The cardiovascular implications are more significant.  These studies just seem to focus on superficial things.  Fifth, did libido problems exist before?  What were the free levels?   This falls in the paucity of data (2 studies) that point to excessive lowering of estradiol effecting libido and sexual performance.

aromatase inhibitors and breast cancer.

flavonoids inhibit aromatase activity

Low T actually the result of higher E through aromatase activity

Quercetin shown to be a good natural aromatase inhibitor