17α-Hydroxypregnenolone

Prohormone

17α-Hydroxypregnenolone is considered a prohormone in the formation of dehydroepiandrosterone (DHEA), itself a prohormone of the sex steroids.

This conversion is mediated by the enzyme 17,20 lyase. As such 17α-hydroxypregnenolone represents an intermediary in the Δ5 pathway that leads from pregnenolone to DHEA. 17α-Hydroxypregnenolone is also converted to 17α-hydroxyprogesterone, a prohormone for glucocorticosteroids and androstenedione through the activity of 3α-hydroxysteroid dehydrogenase.

Clinical use

Measurements of 17α-hydroxypregnenolone are useful in the diagnosis of certain forms of congenital adrenal hyperplasia. In patients with congenital adrenal hyperplasia due to 3β-hydroxysteroid dehydrogenase deficiency 17α-hydroxypregnenolone is increased, while in patients with congenital adrenal hyperplasia due to 17α-hydroxylase deficiency levels are low to absent.

Neurosteroid

17α-hydroxypregnenolone is a known neuromodulator as its acts in the central nervous system. Specifically, it is known to modulate locomotion.

Additional images

File:Steroidogenesis.svg|Steroidogenesis

References

References

1. (April 1999). "Age relationships and sex differences in serum levels of pregnenolone and 17-hydroxypregnenolone in healthy subjects". Clinical Chemistry and Laboratory Medicine.
2. (September 2002). "Longitudinal study of plasma pregnenolone and 17-hydroxypregnenolone in full-term and preterm neonates at birth and during the early neonatal period". The Journal of Clinical Endocrinology and Metabolism.
3. (September 2018). "7α-Hydroxypregnenolone regulating locomotor behavior identified in the brain and pineal gland across vertebrates". General and Comparative Endocrinology.