Steroid hormones in plants and in animals are very important for physiological and developmental regulation. In animals steroid hormones are recognized by nuclear receptors, which transcriptionally regulate specific target genes following binding of the ligand. In addition, numerous rapid effects generated by steroids appear to be mediated by a mechanism not depending on the activation of nucle...

Neurophysiological and behavioral development is particularly complex in adolescence. Youngsters experience strong emotions and impulsivity, reduced self-control, and preference for actions which offer immediate rewards, among other behavioral patterns. Given the growing interest in endocrine effects on adolescent central nervous system development and their implications on later stages of life...

The environmental loading of steroid hormones contained in dairy wastes may cause an adverse effect on aquatic species. To better assess the potential risks of hormone contamination resulting from land application of dairy wastes, various steroid hormones were determined in a typical dairy waste disposal system. Quantitative methods using gas chromatography/mass spectrometry (GC/MS) were develo...

Chst10 adds sulfate to glucuronic acid to form a carbohydrate antigen, HNK-1, in glycoproteins and glycolipids. To determine the role of Chst10 in vivo, we generated systemic Chst10-deficient mutant mice. Although Chst10(-/-) mice were born and grew to adulthood with no gross defects, they were subfertile. Uteri from Chst10(-/-) females at the pro-estrus stage were larger than those from wild-t...

The effects of soybean isoflavones with or without probiotics on tissue fat deposition, plasma cholesterol, and steroid and thyroid hormones were studied in SHR/N-cp rats, an animal model of obesity, and were compared to lean phenotype. We tested the hypothesis that probiotics by promoting the conversion of isoflavone glycosides to their metabolically active aglycone form will have a synergisti...

Steroid hormones are generally thought to pass easily across a plasma membrane into a cell, interacting once inside with soluble nuclear receptors, but recent experiments have demonstrated the importance of membrane-bound receptors in mediating the activity and the metabolism of steroid hormones.

Steroid hormones modulate activity of the nuclear receptor constitutive active receptor (CAR, or constitutive androstane receptor) in mouse liver. Progesterone and testosterone repress the constitutive activity of mouse CAR (mCAR) in cell-mediated transfection assays, whereas estrogens activate the repressed receptor. This repression and activation is not observed with human CAR. To define the ...

Steroid sex hormones play a central role in breast carcinogenesis. Evidence from in vitro and animal studies suggests that phytoestrogens may inhibit the development of mammary tumors through their role in regulating the synthesis, metabolism, and signal transduction of steroid hormones. In a study of 117 case-control pairs of postmenopausal women in Shanghai, we investigated whether the associ...

The biological consequences of steroid hormone-mediated transcriptional activation of target genes might be difficult to predict because alternative splicing of a single neosynthesized precursor RNA can result in production of different protein isoforms with opposite biological activities. Therefore, an important question to address is the manner in which steroid hormones affect the splicing of...

The field of steroid hormone action is well established, although it is barely more than four decades old. Pivotal experiments in the late 1950s and 1960s showed that hormone-binding components exist within nuclei of target tissues and that steroid hormones act by regulating gene expression, rather than directly influencing enzymatic processes. The understanding that steroid hormone receptors i...