Search results for "androgen receptor"
showing 8 items of 48 documents
REDUCTION OF NILUTAMIDE BY NO SYNTHASES : IMPLICATIONS FOR THE ADVERSE EFFECTS OF THIS NITROAROMATIC ANTIANDROGEN DRUG
2003
Nitric oxide synthases (NOSs) are flavohemeproteins that catalyze the oxidation of l-arginine to l-citrulline with formation of the widespread signal molecule NO. Beside their fundamental role in NO biosynthesis, these enzymes are also involved in the formation of reactive oxygen species and in the interactions with some xenobiotic compounds. Nilutamide is a nonsteroidal antiandrogen that behaves as a competitive antagonist of the androgen receptors and is proposed in the treatment of metastatic prostatic carcinoma. However, therapeutic effects of nilutamide are overshadowed by the occurrence of several adverse reactions mediated by toxic mechanism(s), which remain(s) poorly investigated. H…
The non-aromatizable androgen dihydrotestosterone (DHT) facilitates sexual behavior in ovariectomized female rats primed with estradiol
2020
Abstract It is still unclear whether Testosterone (T) increases sexual desire through a stimulation of the androgen receptor in relevant brain regions or through its conversion to estrogens. The aim of this study was to clarify the mechanisms of T facilitation of female sexual desire by assessing the effect of a non-aromatizable androgen (Dihydrotestosterone, DHT) in a validated animal model. Ovariectomized (OVX) Long-Evans rats were treated with oil (O) + O, 10 mcg Estradiol Benzoate (EB) + O, 10 mcg EB + 500 mcg Progesterone (P), O + 500 mcg DHT or 10 mcg EB + 500 mcg DHT (n = 12 per group). EB was administered 48 h, while P and DHT 4 h, prior to 4 sexual behavioral testing sessions in bi…
Effects of combined hormone replacement therapy or its effective agents on the IGF-1 pathway in skeletal muscle.
2010
Objectives To investigate the effects of combined hormone replacement therapy (HRT) and its effective agents on the IGF-1 signaling pathway. Design and methods To examine the effects of HRT on skeletal muscle in vivo, we utilized pre- and post-intervention samples from a randomized double blinded trial with 50–57-year-old women. The intervention included the year-long use of either HRT preparation (2 mg 17β-estradiol, E2; 1 mg norethisterone acetate, NETA, n = 10) or placebo (CO, n = 9). Microarray technology and quantitative PCR (qPCR) were used to study the expression of insulin-like growth factor I (IGF-1) and its splice variants as well as IGF-1 receptor, Akt1, mTOR, FOXO1, FOXO3, atrog…
Anti-androgens for the treatment of hirsutism.
2002
Many alternatives exist for treating hirsutism. Based on an analysis of scientific literature and on the experiences of the author, the most common anti-androgen agents are discussed in this review. Androgen receptor blockers (cyproterone acetate, flutamide and spironolactone), 5 alpha-reductase inhibitors (finasteride) and androgen-suppressing agents (gonadotrophin-releasing hormone [GnRH] agonists, oestroprogestins, corticosteroids and insulin-sensitising agents) are evaluated and compared. The importance of diagnosis in choosing the most appropriate anti-androgen treatment is also discussed.
Determination of Nuclear Prostatic Androgen Receptors by FPLC (Fast Protein Liquid Chromatography)
1987
The experimental detection of steroid receptors, quantitative as well as qualitative, has been received with wide-spread interest in the research of the various effects of steroid hormones during recent years. The quantitative measurement of cyto- and karyoplasmatic prostatic androgen receptors, carried out through such methods as the Dextran-Coated-Charcoal-Method (DCC) (Snochowsky et al. 1977), the gradient centrifugation method (Mainwaring and Milroy 1975; Menon et al. 1978) or the Hydroxyl-apatite process (Murthy et al. 1984; Pavlik and Coulson 1976), represent unprecise or complicated analytical processes, which are due to technical factors, such as proteolytical degradation, the time …
Molecular Analysis of the Androgen Receptor Gene in 52 Patients with Complete or Partial Androgen Insensitivity Syndrome: A Collaborative Study
1992
In patients with androgen insensitivity syndrome (AIS), RFLP study of the androgen receptor gene made it possible to analyze whether deletions or mutations could be responsible for abnormalities in androgen responsiveness. We studied RFLPs of DNA from 25 46,XY patients with partial AIS (PAIS), defined as a concentration of androgen receptor in genital-skin fibroblasts less than 340 fmol/mg DNA, and DNA from 27 46,XY patients with complete AIS (CAIS) with no detectable androgen receptor site. DNA samples were digested with BamHI, EcoRI, HindIII and TaqI restriction enzymes and hybridized with three cDNA probes covering the three domains of the androgen receptor. When we had the maternal and …
Plasma Testosterone Levels and Atherosclerotic Plaque Gene Expression in Men With Advanced Atherosclerosis
2021
Aims: Low plasma testosterone levels have been shown to predict worse outcome in men with severe atherosclerotic disease. We hypothesized that a low plasma testosterone level affects disease risk through changes in gene expression in atherosclerotic plaques. Therefore, we studied plasma testosterone levels in relation to gene expression levels in atherosclerotic plaque tissue of men with advanced atherosclerotic disease.Methods: Plasma testosterone levels were measured in 203 men undergoing carotid endarterectomy. The corresponding atherosclerotic plaque tissue was used for RNA sequencing. First, we assessed how often the androgen receptor gene was expressed in the plaque. Second, correlati…
Endocrine disrupters: the new players able to affect the epigenome
2015
Epigenetics represents the way by which the environment is able to program the genome; there are three main levels of epigenetic control on genome: DNA methylation, post-translational histone modification and microRNA expression. The term Epigenetics has been widened by NIH to include “both heritable changes in gene activity and expression but also stable, long-term alterations in the transcriptional potential of a cell that are not necessarily heritable.” These changes might be produced mostly by the early life environment and might affect health influencing the susceptibility to develop diseases, from cancer to mental disorder, during the entire life span. The most studied environmental i…