Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.1.1.3 (
HSD
)
3,464
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Environmental anti-androgens are increasingly being recognized as potential contributing factors in the chemically induced feminization of wild fish because, by blocking androgen action, they can produce phenotypic effects similar to environmental estrogens. The molecular mechanisms by which anti-androgens and estrogens exert feminizing effects, however, have not been systematically compared. Using a targeted approach, we profiled the expression responses of a suite of 22 genes involved in reproduction, growth and development (processes controlled by androgens and estrogens) in the liver and gonad in adult male and female fathead minnow (Pimephales promelas) exposed to the model anti-androgen flutamide and the model synthetic estrogen 17alpha-ethinylestradiol (EE(2)). Both flutamide (320 microg/L) and EE(2) (10ng/L) produced phenotypic effects indicative of feminization (induction of plasma vitellogenin, reduced gonadosomatic index, and reduced secondary sex characters), although for the chosen test concentrations EE(2) was the more potent. For the genes studied, flutamide and EE(2) produced distinct expression profiles, suggesting that they largely operate via distinct molecular mechanisms. As examples, in liver EE(2) (but not flutamide) exposure up-regulated estrogen receptor (ER) alpha mRNA, whereas flutamide exposure increased ERbeta and ERgamma mRNAs in males and resulted in decreased androgen receptor (AR) mRNA in females. In the testis, flutamide up-regulated genes coding for enzymes involved in androgen biosynthesis (cytochrome P450 17 [CYP17] and 11beta-hydroxysteroid dehydrogenase [11beta-
HSD
]) implying an inhibitory action on androgen negative feedback pathways. EE(2), in contrast, inhibited the expression of enzymes involved in androgen biosynthesis (CYP17, 11beta-
HSD
and 17beta-hydroxysteroid dehydrogenase [17beta-HSD]). There were also some commonalities in the molecular mechanisms of flutamide and EE(2) action, including the down-regulation of gonadal sex steroid receptor expression (gonadal AR and ovarian ERalpha), increased expression of genes coding for estrogen-producing enzymes (cytochrome P450 19A and B [CYP19A and CYP19B]), decreased expression of genes involved in testis differentiation (anti-Mullerian hormone [AMH] and doublesex and mab-3 related transcription factor 1 [DMRT1]), and decreased expression of hepatic genes which mediate wider physiological processes such as somatic growth (growth hormone [GH], GH receptor [
GHR
], insulin-like growth factor-I [IGF-I], IGF-I receptor [IGF-IR], thyroid hormone receptor alpha [TRalpha] and beta [TRbeta]).
...
PMID:Gene expression profiles revealing the mechanisms of anti-androgen- and estrogen-induced feminization in fish. 1722 21
The purpose of this study was to investigate the association between the
GHR
exon 3 fl/d3 polymorphism and body composition traits in Brazilian cohorts of normal post-menarche adolescent girls and in post-menopausal women with and without osteoporosis. First, multiplex PCR and quantitative PCR (TaqMan) were used with 105 DNA samples from the general Brazilian population to validate the SNP rs6873545 as a surrogate marker for the
GHR
polymorphism. Subsequently, genotyping was carried out to evaluate associations for this polymorphism in 136 post-menarche adolescents and 175 post-menopausal women, who were evaluated for body composition traits such as bone mineral density and fat-free mass. Statistical analysis used an independent sample t test, one-way ANOVA test and post hoc Tukey
HSD
test. Significant values were assumed by p < 0.05. Genotyping indicated complete linkage disequilibrium between the
GHR
polymorphism and the SNP alleles (r(2) = 1.0). Adolescents and healthy post-menopausal women showed no genotype associations for body composition traits or osteoporosis. However, a lower total body bone mineral density was observed in fl/fl post-menopausal women with osteoporosis (p = 0.0004). These results suggest that the SNP rs6873545 can be used as a surrogate for the
GHR
fl/d3 polymorphism due to linkage disequilibrium in the Brazilian population and that the fl/fl genotype is a severity-related risk factor for osteoporosis, but did not appear to be associated with disease status.
...
PMID:The exon 3 polymorphism of the growth hormone receptor is a severity-related factor for osteoporosis. 2381 3