Background. Metabolic syndrome (MetS) and obesity are known risk factors for gastroesophageal reflux disease (GERD), which is often found in patients with endocrine disorders, such as thyroid dysfunction and hypopituitarism. To clarify the relationship of endocrine disease with GERD, we investigated the symptoms of GERD in patients with various endocrine diseases.
View Article and Find Full Text PDFWe identified a novel synthetic steroid, S42, as a promising candidate of selective androgen receptor (AR) modulator. Results of the whole-cell binding assay using COS-7 cells exogenously expressing various steroid receptors indicated that S42 specifically binds to AR and progesterone receptor. When orchiectomized Sprague Dawley rats were administered with S42 for 3 wk, the muscle weight of the levator ani was increased as markedly as that induced by 5alpha-dihydrotestosterone (DHT), but the weight of the prostate was not elevated at any doses in contrast to DHT.
View Article and Find Full Text PDFHypogonadism is associated with increased fat mass and dysregulation of metabolic homeostasis in men. Our previous study revealed that androgen receptor (AR)-null male mice (ARL-/Y) develop late-onset obesity and are leptin-resistant. The present study evaluated how hypothalamic AR contributes to central leptin-signal transducer and activator of transcription 3 (STAT3) signaling.
View Article and Find Full Text PDFSteroidogenic factor 1 (SF-1)/adrenal 4 binding protein is an essential nuclear receptor for steroidogenesis, as well as for adrenal and gonadal gland development. We have previously clarified that adenovirus-mediated forced expression of SF-1 can transform long-term cultured mouse bone marrow mesenchymal cells (BMCs) into ACTH-responsive steroidogenic cells. In the present study, we extended this work to adipose tissue-derived mesenchymal cells (AMCs) and compared its steroidogenic capacity with those of BMCs prepared from the identical mouse.
View Article and Find Full Text PDFThe mechanism for the steroidogenic tissue or cell-specific expression of SF-1 has not been well clarified. We examined whether the methylation status of a large CpG island in the first intron of mouse SF-1 gene is associated with the expression level of SF-1 in cultured cells and in tissues. The island consists of three small islands (ICI-1, ICI-2, and ICI-3).
View Article and Find Full Text PDFGlucocorticoid-induced T-cell apoptosis is supposed to require the change of gene expression. Enhanced expression of proapoptotic gene or inhibited expression of antiapoptotic gene seems to be necessary, although the real target gene remain to be elucidated. Recently, it was reported that extracellular signal-regulated protein kinase (ERK) inhibits glucocorticoid-induced T-cell apoptosis.
View Article and Find Full Text PDFSteroid receptors are evoluted from the common ancestor and have the same structure as steroid receptor superfamily. The nuclear receptors are characterized by a central DNA binding domain with specific DNA sequences known as hormone response element, ligand binding domain in the C terminal and N terminal domain with the tissue specificity. Nuclear receptor superfamily is divided into four classes based on the dimerization and DNA binding properties, homodimers as steroid hormone receptor, heterodimers with RXR, homodimers and monomers.
View Article and Find Full Text PDFSteroidogenic factor 1/adrenal 4 binding protein (SF-1/Ad4BP) is an essential nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. Mesenchymal bone marrow cells (BMCs) contain pluripotent progenitor cells, which differentiate into multiple lineages. In a previous study, we reported that adenovirus-mediated forced expression of SF-1 could transform mouse primary long-term cultured BMCs into steroidogenic cells.
View Article and Find Full Text PDFBackground: Atrazine is a potent endocrine disruptor that increases aromatase expression in some human cancer cell lines. The mechanism involves the inhibition of phosphodiesterase and subsequent elevation of cAMP.
Methods: We compared steroidogenic factor 1 (SF-1) expression in atrazine responsive and non-responsive cell lines and transfected SF-1 into nonresponsive cell lines to assess SF-1's role in atrazine-induced aromatase.
The popular herbicide atrazine is an endocrine disruptor that demasculinizes and feminizes several species of animals, and co-relates with breast and reproductive disorders in mammalians. We recently reported that atrazine induces human aromatase gene expression via promoter II (ArPII) in a steroidogenic factor 1 (SF-1)-dependent manner. Here, we show that knockdown of SF-1 abolishes ArPII induction by atrazine in H295R cells, which harbor high SF-1 expression and are originally atrazine-responsive.
View Article and Find Full Text PDFThe androgen-androgen receptor (AR) system plays vital roles in a wide array of biological processes, including prostate cancer development and progression. Several growth factors, such as insulin-like growth factor 1 (IGF1), can induce AR activation, whereas insulin resistance and hyperinsulinemia are correlated with an elevated incidence of prostate cancer. Here we report that Foxo1, a downstream molecule that becomes phosphorylated and inactivated by phosphatidylinositol 3-kinase/Akt kinase in response to IGF1 or insulin, suppresses ligand-mediated AR transactivation.
View Article and Find Full Text PDFCarotid intima-media thickness (IMT), an indicator of atherosclerosis and coronary heart disease (CHD) is usually evaluated by eye measurement under B-scope carotid artery ultrasonography. However, the axial resolution of this system is >/=0.1 mm, which causes difficulties in respect to accuracy and reproducibility.
View Article and Find Full Text PDFObjective: Glucocorticoid is widely used for the treatment of diseases such as hematological malignancies. Glucocorticoid sensitivity is different from person to person and the mechanism of the regulation of glucocorticoid sensitivity is not well known. Glucocorticoid resistance is a major clinical problem.
View Article and Find Full Text PDFIn animal experiments, adrenal cortical tissue has been successfully regenerated through xenotransplantation of cloned adrenocortical cells, suggesting that the intraadrenal stem cells required for such tissue formation may be present in the adrenal cortex. Stable expression of Ad4BP/SF-1, a key factor for adrenal and gonadal development and steroidogenesis, has been shown to direct embryonic stem cells toward the steroidogenic lineage. However, this steroidogenic capacity was very limited since progesterone was only produced in the presence of an exogenous substrate.
View Article and Find Full Text PDFPreviously, we identified a transcriptional coactivator for the activation function-1 (AF-1) domain of the human androgen receptor (AR) and designated it androgen receptor N-terminal domain transactivating protein-1 (ANT-1). This coactivator, which contains multiple tetratricopeptide repeat (TPR) motifs from amino acid (aa) 294, is identical to a component of U5 small nuclear ribonucleoprotein particles and binds specifically to the AR or glucocorticoid receptor. Here, we identified four distinct functional domains.
View Article and Find Full Text PDFGlucocorticoid exerts its anti-inflammatory effect mainly through the suppression of both AP-1 and NF-kappaB by its receptor, glucocorticoid receptor(GR). AP-1 and NF-kappaB are also supposed to be involved in glucocorticoid resistance. Here we describe the role of AP-1 and NF-kappaB in glucocorticoid resistance.
View Article and Find Full Text PDFAndrogen signaling plays key roles in the development and progression of prostate cancer, and numerous ongoing studies focus on the regulation of androgen receptor (AR) transactivity to develop novel therapies for the treatment of androgen-independent prostate cancer. FoxH1, a member of the Forkhead-box (FOX) gene family of transcription factors, takes part in mediating transforming growth factor-beta/activin signaling through its interaction with the Smad2.Smad4 complex.
View Article and Find Full Text PDFContext: Recent imaging studies revealed that androgen receptor (AR) is ligand-dependently translocated from the cytoplasm into the nucleus and forms intranuclear fine foci. In this study, we examined whether intracellular dynamics of mutant ARs detected in two androgen insensitivity syndrome (AIS) patients was impaired.
Objective: ARs with mutations in the DNA-binding domain were functionally characterized and compared with the wild-type AR.
Androgen receptor (AR) null male mice (AR(L-/Y)) revealed late-onset obesity, which was confirmed by computed tomography-based body composition analysis. AR(L-/Y) mice were euphagic compared with the wild-type male (AR(X/Y)) controls, but they were also less dynamic and consumed less oxygen. Transcript profiling indicated that AR(L-/Y) mice had lower transcripts for the thermogenetic uncoupling protein 1, which was subsequently found to be ligand-dependently activated by AR.
View Article and Find Full Text PDFDehydroepiandrosterone-sulfate, the sulfated form of dehydroepiandrosterone, is the most abundant steroid in young adults, but gradually declines with aging. In humans, the clinical application of dehydroepiandrosterone targeting some collagen diseases, such as systemic lupus erythematosus, as an adjunctive treatment has been applied in clinical trial. Here, we report that dehydroepiandrosterone may negatively regulate the mitogen-activated protein kinase pathway in humans via a novel dual specificity protein phosphatase, DDSP (dehydroepiandrosterone-enhanced dual specificity protein phosphatase).
View Article and Find Full Text PDFBone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH).
View Article and Find Full Text PDF