Drugs such as tamoxifen, which act at the estrogen receptor (ER), have very different in vitro and in vivo effects from those of the native hormone. Previous research has established that different ligands induce distinct conformational changes in the ER, thus affecting the interactions of the receptor with cell-specific co-activating or co-repressing proteins (cofactors) and estrogen response ...

Ghrelin, an endogenous ligand for the GH secretagogue receptor, is predominantly produced in the stomach. Little is known about the regulation mechanism of gastric ghrelin. Here, we report that estrogen synthesized in the stomach induces rat gastric ghrelin gene expression and production. We established a gastric ghrelin cell enrichment method using Percoll centrifugation and then studied the e...

Gelatinase A (matrix metalloproteinase-2) plays a prominent role in multiple biologic processes. Prior studies have established critical roles for gelatinase A transcriptional regulation by defined enhancer elements. To determine possible functional single nucleotide polymorphisms within these elements, we determined the single nucleotide polymorphism distribution within 1,665 bp of the gelatin...

Tumor necrosis factor-alpha (TNF-alpha) is involved in the pathogenesis of vascular disease. Clinical studies have shown that postmenopausal women have higher serum TNF-alpha levels; however, whether this increase in TNF-alpha is associated with vascular dysfunction is unknown. We investigated whether estrogen deficiency is associated with increased serum TNF-alpha levels and tested the effects...

BACKGROUND Estrogen receptors (ER) alpha and beta play an important role in breast cancer. Recently, systemic adjuvant endocrine therapy with selective estrogen receptor modulator (SERM) tamoxifen has been challenged by aromatase inhibitors. Compared to antiestrogens, third-generation aromatase inhibitors (anastrozole and letrozole) exhibit an improved efficacy and tolerability. MATERIALS AND...

Environmental chemicals with estrogenic activities have been suggested to be associated with deleterious effects in animals and humans. To characterize estrogenic chemicals and their mechanisms of action, we established in vitro and cell culture assays that detect human estrogen receptor [alpha] (hER[alpha])-mediated estrogenicity. First, we assayed chemicals to determine their ability to modul...