"If hyperandrogenism drives the microbial composition of the gut, it would be interesting to determine if treatment of PCOS with androgen antagonists
or oral contraceptives results in recovery of the gut microbiome and improvement of the PCOS metabolic phenotype" wrote Mr.
Torres noted that "if hyper-androgenism drives the microbial composition of the gut, it would be interesting to determine if treatment of PCOS with androgen antagonists
or oral contraceptives results in recovery of the gut microbiome and improvement of the PCOS metabolic phenotype.
(18) Low androgen levels, such as in those who are androgen deficient or using androgen antagonists
, can result in reduced quality and quantity of meibomian lipids which is seen clinically as increased tear film instability and reduced tear break-up time (TBUT).
These studies led to the identification of several estrogen receptor (ER) agonists as being androgen antagonists. However, although an earlier study demonstrated that 2-tert-butylanthraquinone and benzoanthrone may act as weak agonists to the human androgen receptor (hAR) at high concentrations (Araki et al.
Interestingly, when investigating substances with reported high endocrine-disrupting effects such as nonylphenol or bisphenol A (both are estrogenic) and vinclozolin (an androgen antagonist), none of the substances, with the exception of TCDD, binds to or activates the steroid receprors by > 1 % of the endogenous ligand (Table 4).
CONCLUSIONS: The results show that the OECD Hershberger bioassay protocol is reproducible and transferable across laboratories with androgen agonists, weak androgen antagonists, and a 5[alpha]-reductase inhibitor.
Four androgen antagonists and a 5[alpha]-reductase inhibitor were used as test substances.
Based on this phase 1 validation study, the protocols have been refined, and the next phase of the OECD validation program will test the protocol with selected doses of weak androgen agonists, androgen antagonists
, a 5[alpha]-reductase inhibitor, and chemicals having no androgenic activity.
All test systems showed that bicalutamide and hydroxyflutamide act as potent androgen antagonists
(Ma et al.
This modified system was successfully used by several investigators for assaying androgen antagonists
(Peers et al.