The objective of this work was to evaluate the effects of testosterone (T) and 17beta-estradiol (E(2)) on coronary microvascular endothelial cells (CMECs) of male and female rats. To analyze the short-term effects of such sex steroid hormones on intracellular Ca(2+) concentration ([Ca(2+)](i)) kinetics, we used the chelating agent fura-2 acetoxymethyl ester. We also explored the possibility of ...

The functional importance of sex steroid hormones (testosterone and estrogens), derived from extragonadal tissues, has recently gained significant appreciation. Circulating dehydroepiandrosterone (DHEA) is peripherally taken up and converted to testosterone by 3beta-hydroxysteroid dehydrogenase (HSD) and 17beta-HSD, and testosterone in turn is irreversibly converted to estrogens by aromatase cy...

Modulating steroid hormone levels is a curative and preventive measure for Cushing's syndrome, aldosteronism, and various stress-triggered symptoms. Polyphenols have been reported to inhibit steroidogenic enzymes such as 3β-hydroxysteroid dehydrogenase (3β-HSD) and aromatase. However, evidence for their inhibitory effects is fragmentary because it has been determined in studies with small group...

G1-phase cell cycle defects, such as alterations in cyclin D1 or cyclin-dependent kinase (cdk) levels, are seen in most tumors. For example, increased cyclin D1 and decreased cdk6 levels are seen in many human breast tumors. Overexpression of cdk6 in breast tumor cells in culture has been shown to suppress proliferation, unlike the growth stimulating effects of its close homolog, cdk4. In addit...

BACKGROUND An array of environmental compounds is known to possess endocrine disruption (ED) potentials. Bisphenol A (BPA) and bisphenol A dimethacrylate (BPA-DM) are monomers used to a high extent in the plastic industry and as dental sealants. Alkylphenols such as 4-n-nonylphenol (nNP) and 4-n-octylphenol (nOP) are widely used as surfactants. OBJECTIVES We investigated the effect in vitro o...

The effects of 4-hydroxyandrostenedione (4-OHA) and other aromatase inhibitors, 10-propargylestr-4-ene-3,17-dione and imidazo|l,5-a|3,4,5,6-tetrahydropyrin-6-yl-(4-benzonitrile), as well as 5a-reductase in hibitors /V./V-diethyW-methyl-S-oxo^-aza-Sa-androstane-n/J-carboxyamide and 4-methyl-3-oxo-4-aza-androsta-5-ene-17-ol were investigated in prostatic tissue from six patients with benign prost...

Estrogenic functions in regulating behavioral states such as motivation, mood, anxiety, and cognition are relatively well documented in female humans and animals. In males, however, although the entire enzymatic machinery for producing estradiol and the corresponding receptors are present, estrogenic functions have been largely neglected. Therefore, and as a follow-up study to previous research...

Dehydroepiandrosterone (DHEA), a precursor of sex steroid hormones, is synthesized by cholesterol side-chain cleavage cytochrome P-450 and 17alpha-hydroxylase cytochrome P-450 mainly from cholesterol and converted to testosterone and estrogen by 3beta-hydroxysteroid dehydrogenase (3beta-HSD), 17beta-HSD, and aromatase cytochrome P-450. Although sex steroid hormones have important effects in the...

Gliomas are the most common type of primary malignant brain tumor and have a very poor prognosis. Little is known, however, about the etiology of these tumors. Evidence from a number of sources suggests that endogenous steroid hormones may play a role in the development of gliomas. First, the descriptive epidemiology of glioma suggests a relative protection of females compared with males, parti...

Gonadal differentiation in frogs is affected by sex steroids and thyroid hormones (THs); however, the genes controlling differentiation and the molecular effects of THs in the gonad are not clear and have only been investigated in a few anuran species. In this study, we established developmental profiles and TH regulation of sex steroid- and TH-related genes in the gonad-mesonephros complex (GM...