The 5 Alpha-Reductase Isozyme Family: A Review of Basic Biology and Their Role in Human Diseases

Department of Urology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
Advances in Urology 01/2012; 2012(1687-6369):530121. DOI: 10.1155/2012/530121
Source: PubMed

ABSTRACT Despite the discovery of 5 alpha-reduction as an enzymatic step in steroid metabolism in 1951, and the discovery that dihydrotestosterone is more potent than testosterone in 1968, the significance of 5 alpha-reduced steroids in human diseases was not appreciated until the discovery of 5 alpha-reductase type 2 deficiency in 1974. Affected males are born with ambiguous external genitalia, despite normal internal genitalia. The prostate is hypoplastic, nonpalpable on rectal examination and approximately 1/10th the size of age-matched normal glands. Benign prostate hyperplasia or prostate cancer does not develop in these patients. At puberty, the external genitalia virilize partially, however, secondary sexual hair remains sparse and male pattern baldness and acne develop rarely. Several compounds have been developed to inhibit the 5 alpha-reductase isozymes and they play an important role in the prevention and treatment of many common diseases. This review describes the basic biochemical properties, functions, tissue distribution, chromosomal location, and clinical significance of the 5 alpha-reductase isozyme family.

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Available from: Alejandro Godoy, Jul 26, 2015
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    • "Testosterone is the most abundant androgen in serum, synthesised by Leydig cells of the testes under the control of the hypothalamus and anterior pituitary gland. It has a variety of effects including growth of male genitalia, building and maintaining muscle mass, development of libido and initiation of spermatogenesis at puberty (Azzouni et al., 2012). Intracellularly, testosterone (T) is converted to its more active metabolite dihydrotestosterone (DHT) by NADPH dependent; membrane bound (microsomal ) human 5a-reductase (5a-R) (EC enzyme (Fig. 1). "
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