Multiple functions of type 10 17beta-hydroxysteroid dehydrogenase

Trends Endocrinol Metab. May-Jun 2005;16(4):167-75. doi: 10.1016/j.tem.2005.03.006.


Human 17beta-hydroxysteroid dehydrogenase type 10 (17beta-HSD10) is a mitochondrial enzyme encoded by the SCHAD gene, which escapes chromosome X inactivation. 17Beta-HSD10/SCHAD mutations cause a spectrum of clinical conditions, from mild mental retardation to progressive infantile neurodegeneration. 17Beta-HSD10/SCHAD is essential for the metabolism of isoleucine and branched-chain fatty acids. It can inactivate 17beta-estradiol and steroid modulators of GABA(A) receptors, and convert 5alpha-androstanediol into 5alpha-dihydrotestosterone (DHT). Certain malignant prostatic epithelial cells contain high levels of 17beta-HSD10, generating 5alpha-DHT in the absence of testosterone. 17Beta-HSD10 has an affinity for amyloid-beta peptide, and might be linked to the mitochondrial dysfunction seen in Alzheimer's disease. This versatile enzyme might provide a new drug target for neuronal excitability control and for intervention in Alzheimer's disease and certain cancers.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • 17-Hydroxysteroid Dehydrogenases / genetics
  • 17-Hydroxysteroid Dehydrogenases / metabolism
  • 17-Hydroxysteroid Dehydrogenases / physiology*
  • 3-Hydroxyacyl CoA Dehydrogenases / genetics
  • 3-Hydroxyacyl CoA Dehydrogenases / metabolism
  • Alzheimer Disease / enzymology
  • Alzheimer Disease / etiology
  • Animals
  • Gonadal Steroid Hormones / metabolism
  • Humans
  • Isoleucine / metabolism
  • Neurotransmitter Agents / metabolism
  • Steroids / metabolism


  • Gonadal Steroid Hormones
  • Neurotransmitter Agents
  • Steroids
  • Isoleucine
  • 17-Hydroxysteroid Dehydrogenases
  • 3-Hydroxyacyl CoA Dehydrogenases
  • HSD17B10 protein, human