Home About us Contact | |||
Nonsteroidal Aromatase Inhibitor (nonsteroidal + aromatase_inhibitor)
Selected AbstractsSynthesis and Evaluation of a Dimer of 2-(4-Pyridylmethyl)-1-indanone as a Novel Nonsteroidal Aromatase Inhibitor.CHEMINFORM, Issue 44 2004Ranju Gupta Abstract For Abstract see ChemInform Abstract in Full Text. [source] Nonsteroidal aromatase inhibitors: Recent advancesMEDICINAL RESEARCH REVIEWS, Issue 3 2002Maurizio Recanatini Abstract Aromatase is the cytochrome P450 enzyme responsible for the last step of estrogen biosynthesis, and aromatase inhibitors constitute an important class of drugs in clinical use for the treatment of breast cancer. Nonsteroidal aromatase inhibitors (NSAIs) are competitive inhibitors of aromatase, which bind to the enzyme active site by coordinating the iron atom present in the heme group of the P450 protein. Presently, third generation NSAIs are in use, and research efforts are being carried out both to identify new molecules of therapeutic interest and to clarify the mechanism of action. In this article, we present a survey of the compounds that have been recently reported as NSAIs, to provide a broad view on the general structure,activity relationships of the class. Moreover, starting from the current knowledge of the mechanistic aspects of aromatase action and from recent theoretical work on the molecular modeling of both enzyme and inhibitors, we try to indicate a way to integrate these different studies in view of a more general understanding of the aromeatase-inhibitor system. Finally, some aspects regarding the possible future development of the field are considered briefly. © 2002 Wiley Periodicals, Inc. Med Res Rev, 22, No. 3, 282,304, 2002; Published online in wiley InterScience (www.interscience.wiley.com). DOI 10.1002/med.10010 [source] Expression of AMH, SF1, and SOX9 in gonads of genetic female chickens during sex reversal induced by an aromatase inhibitorDEVELOPMENTAL DYNAMICS, Issue 2 2001Séverine Vaillant Abstract Aromatase inhibitors administered prior to histological signs of gonadal sex differentiation can induce sex reversal of genetic female chickens. Under the effects of Fadrozole (CGS 16949A), a nonsteroidal aromatase inhibitor, the right gonad generally becomes a testis, and the left gonad a testis or an ovotestis. We have compared the expression pattern of the genes encoding AMH (the anti-Müllerian hormone), SF1 (steroidogenic factor 1), and SOX9 (a transcription factor related to SRY) in these sex-reversed gonads with that in control testes and ovaries, using in situ hybridization with riboprobes on gonadal sections. In control males, the three genes are expressed in Sertoli cells of testicular cords; however, only SOX9 is male specific, since as observed previously AMH and SF1 but not SOX9 are expressed in the control female gonads. In addition to testicular-like cords, sex-reversed gonads present many lacunae with a composite, thick and flat epithelium. We show that during embryonic and postnatal development, AMH, SF1 and SOX9 are expressed in the epithelium of testicular-like cords and in the thickened part but not in the flattened part of the epithelium of composite lacunae. AMH and SF1 but not SOX9 are expressed in follicular cells of ovotestes. Coexpression of the three genes, of which SOX9 is a specific Sertoli-cell marker, provides strong evidence for the transdifferentiation of ovarian into testicular epithelium in gonads of female chickens treated with Fadrozole. © 2001 Wiley-Liss, Inc. [source] Effects of a nonsteroidal aromatase inhibitor on gonadal differentiation of bluegill sunfish Lepomis macrochirusAQUACULTURE RESEARCH, Issue 9 2010Ze-Xia Gao Abstract In the present study, the efficacy of Letrozole, a potent nonsteroidal aromatase inhibitor (AI), on gonadal sex differentiation and sex reversal was examined in bluegill sunfish (Lepomis macrochirus). In Experiment 1, using AI diet treatments (50, 150, 250 and 500 mg kg,1) from 30 to 90 days posthatch (dph), AI interrupted ovarian cavity formation at a dose of 500 mg kg1 diet and one intersex fish was identified in this group. The proportions of males in all the treated groups were significantly higher than those in the control group. In Experiment 2, using AI immersion treatments (250, 500 and 1000 ,g L,1) during 30,50 dph, the treated groups of 500 and 1000 ,g L,1 produced significantly more males than the control and 250 ,g L,1 groups. Histological examination revealed no differences in ovary or testis tissue between control and AI-treated fish. There were no significant differences detected in body weight and length among the AI treated and control groups (P>0.05) for both experiments. The results from these two experiments suggest that inhibition of aromatase activity by AI could influence sex differentiation in bluegill sunfish. [source] |