Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 1972 Jul;128(4):945–952. doi: 10.1042/bj1280945

16-Unsaturated C19 3-oxo steroids as metabolic intermediates in boar testis

P J Brophy 1, D B Gower 1
PMCID: PMC1173914  PMID: 4404770

Abstract

1. The formation of the two 16-unsaturated alcohols 5α-androst-16-en-3α-ol and 5α-androst-16-en-3β-ol from [5α-3H]5α-androst-16-en-3-one has been demonstrated in boar testis homogenates. 2. The optimum yield (23%) of the 3α-alcohol was obtained in the presence of NADPH, whereas that for the 3β-alcohol (74%) was obtained when NADH was the added cofactor. 3. The two alcohols were not interconvertible. 4. Prolonged storage of boar testis tissue at −20°C abolished the ability to form all androst-16-enes except androsta-4,16-dien-3-one from [4-14C]progesterone. 5. The production of 5α-androst-16-en-3-one and the two alcohols from [7α-3H]androsta-4,16-dien-3-one only occurred when fresh tissue was used, whereas reduction of [5α-3H]5α-androst-16-en-3-one was unaffected by storage of testis at −20°C. 6. NADPH was the preferred cofactor for the reduction of androsta-4,16-dien-3-one. 7. The previously established conversion of androsta-5,16-dien-3β-ol into androsta-4,16-dien-3-one was shown to be reversible, NADH and NADPH being equally effective cofactors. 8. Pathways of biosynthesis of 5α-androst-16-en-3α- and 3β-ols, with the C19 3-oxo steroids as intermediates, are presented.

Full text

PDF
947

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ahmad N., Gower D. B. The biosynthesis of some androst-16-enes from C21 and C19 steroids in boar testicular and adrenal tissue. Biochem J. 1968 Jun;108(2):233–241. doi: 10.1042/bj1080233. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. GOWER D. B., HASLEWOOD G. A. Biosynthesis of androst-16-en-3alpha-o1 from acetate by testicular slices. J Endocrinol. 1961 Dec;23:253–260. doi: 10.1677/joe.0.0230253. [DOI] [PubMed] [Google Scholar]
  3. Gower D. B. 16-Unsaturated C 19 steroids. A review of their chemistry, biochemistry and possible physiological role. J Steroid Biochem. 1972 Jan;3(1):45–103. doi: 10.1016/0022-4731(72)90011-8. [DOI] [PubMed] [Google Scholar]
  4. Gower D. B., Ahmad N. Studies on the biosynthesis of 16-dehydro steroids. The metabolism of [4-14C]pregnenolone by boar adrenal and testis tissue in vitro. Biochem J. 1967 Aug;104(2):550–556. doi: 10.1042/bj1040550. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gower D. B., Daly J. R., Snodgrass G. J., Stern M. I. Steroid excretion and biosynthesis with special reference to C19-delta16-steroids in an infant with a virilizing adrenocortical carcinoma. Acta Endocrinol (Copenh) 1970 Mar;63(3):562–576. doi: 10.1530/acta.0.0630562. [DOI] [PubMed] [Google Scholar]
  6. Gower D. B., Loke K. H. Studies on the subcellular location and stability of the enzyme system involved in the biosynthesis of 5,16-androstadien-3 -ol from 3 -hydroxy-5-pregnen-20-one (pregnenolone). Biochim Biophys Acta. 1971 Dec 15;250(3):614–616. doi: 10.1016/0005-2744(71)90267-1. [DOI] [PubMed] [Google Scholar]
  7. Katkov T., Gower D. B. The biosynthesis of 5 alpha-androst-16-en-3-one from progesterone by boar testis homogenate. Biochim Biophys Acta. 1968 Sep 2;164(1):134–136. doi: 10.1016/0005-2760(68)90082-9. [DOI] [PubMed] [Google Scholar]
  8. Katkov T., Gower D. B. The biosynthesis of androst-16-enes in boar testis tissue. Biochem J. 1970 Apr;117(3):533–538. doi: 10.1042/bj1170533. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Lisboa B. P., Palmer R. F. Application of thin-layer chromatographic techniques to the separation of delta-16-C-19-steroids and related compounds. Anal Biochem. 1967 Jul;20(1):77–85. doi: 10.1016/0003-2697(67)90267-9. [DOI] [PubMed] [Google Scholar]
  10. Loke K. H., Gower D. B. The intermediary role of 5-pregnene-3 ,20 -diol in the biosynthesis of 16-unsaturated C 19 steroids in boar testis. Biochem J. 1972 Apr;127(3):545–551. doi: 10.1042/bj1270545. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Melrose D. R., Reed H. C., Patterson R. L. Androgen steroids associated with boar odour as an aid to the detection of oestrus in pig artificial insemination. Br Vet J. 1971 Oct;127(10):497–502. doi: 10.1016/s0007-1935(17)37337-2. [DOI] [PubMed] [Google Scholar]
  12. Ward M. G., Engel L. L. Reversibility of steroid delta-isomerase. II. The reaction sequence in the conversion of androst-4-ene-3,17-dione to 3-beta-hydroxyandrost-5-en-17-one by sheep adrenal microsomes. J Biol Chem. 1966 Jul 10;241(13):3147–3153. [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES