Cytochrome P450 oxidoreductase deficiency

Cytochrome P450 oxidoreductase deficiency
Other namesPORD
SpecialtyEndocrinology

Cytochrome P450 oxidoreductase deficiency (PORD)[1] is a rare disease and inborn error of metabolism caused by deficiency of cytochrome P450 oxidoreductase (POR). POR is a 2-flavin protein that is responsible for the transfer of electrons from NADPH to all 50 microsomal cytochrome P450 (CYP450) enzymes.[2][3] This includes the steroidogenic enzymes CYP17A1 (17α-hydroxylase/17,20-lyase), CYP19A1 (aromatase), and CYP21A2 (21-hydroxylase); CYP26B1 (metabolizes retinoic acid); and the hepatic drug-metabolizing CYP450 enzymes (e.g., CYP3A4),[4] among many other CYP450 enzymes.[3] Virilization of female infants in PORD may also be caused by alternative biosynthesis of 5α-dihydrotestosterone via the so-called "androgen backdoor pathway".[5][6] The ABS component of severe forms of PORD is probably caused by CYP26B1 deficiency, which results in retinoic acid excess and defects during skeletal embryogenesis.[3] All forms of PORD in humans are likely partial, as POR knockout in mice results in death during prenatal development.[3]

  1. ^ Flück, Christa E.; Pandey, Amit V. (2019-01-01), "Human P450 Oxidoreductase Deficiency", in Huhtaniemi, Ilpo; Martini, Luciano (eds.), Encyclopedia of Endocrine Diseases (Second Edition), Academic Press, pp. 431–443, doi:10.1016/b978-0-12-801238-3.64966-8, ISBN 978-0-12-812200-6, S2CID 80510456, retrieved 2020-02-18
  2. ^ Pandey, Amit V.; Flück, Christa E. (May 2013). "NADPH P450 oxidoreductase: structure, function, and pathology of diseases". Pharmacology & Therapeutics. 138 (2): 229–254. doi:10.1016/j.pharmthera.2013.01.010. ISSN 1879-016X. PMID 23353702.
  3. ^ a b c d Mark A. Sperling (10 April 2014). Pediatric Endocrinology E-Book. Elsevier Health Sciences. pp. 497–. ISBN 978-1-4557-5973-6.
  4. ^ Burkhard, Fabian Z.; Parween, Shaheena; Udhane, Sameer S.; Flück, Christa E.; Pandey, Amit V. (January 2017). "P450 Oxidoreductase deficiency: Analysis of mutations and polymorphisms". The Journal of Steroid Biochemistry and Molecular Biology. 165 (Pt A): 38–50. doi:10.1016/j.jsbmb.2016.04.003. ISSN 1879-1220. PMID 27068427.
  5. ^ Masiutin, Maxim; Yadav, Maneesh (2023). "Alternative androgen pathways". WikiJournal of Medicine. 10: X. doi:10.15347/WJM/2023.003. S2CID 257943362.
  6. ^ Reisch N, Taylor AE, Nogueira EF, Asby DJ, Dhir V, Berry A, Krone N, Auchus RJ, Shackleton CH, Hanley NA, Arlt W (October 2019). "Alternative pathway androgen biosynthesis and human fetal female virilization". Proceedings of the National Academy of Sciences of the United States of America. 116 (44): 22294–22299. Bibcode:2019PNAS..11622294R. doi:10.1073/pnas.1906623116. PMC 6825302. PMID 31611378.