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A steroid that serves as an intermediate in the biosynthesis of numerous hormones, including progesterone. Serum levels are elevated in a rare form of congenital adrenal hyperplasia.
References in periodicals archive ?
In the smooth endoplasmic reticulum of Leydig cell, pregnenolone derived from cholesterol is metabolized into progesterone by the action of HSD3B1.
The levels of 17a-hydroxyprogesterone and pregnenolone in the healthy boys did not vary significantly among the different adrenarche ages, from approximately 6-8 years old (before puberty initiation) to 9 years old.
Based on her symptoms, I suspected low pregnenolone might be at the root of Audrey's complaints.
Androgen synthesis predominantly takes place in thecal cells which have LH receptors and subsequent signaling and activation of CYP17 enzyme convert pregnenolone and progesterone to dehydroepiandrosterone (DHEA) and androstenedione, respectively.
Malaterre et al., "Pregnenolone sulfate enhances neurogenesis and PSA-NCAM in young and aged hippocampus," Neurobiology of Aging, vol.
The first one acts by converting pregnenolone in to 17OH-pregnenolone and progesterone into 17OH-progesterone; the 17,20-lyase activity converts 17OH-pregnenolone into dehydroepiandrosterone and, to a lesser extent, 17OH-progesterone into androstenedione [15-17].
Moreover, the expression of ovarian 3[beta]-HSD, the enzyme responsible for the conversion of pregnenolone in P4, also follows the expression pattern of PRLR throughout the reproductive cycle of L.
(2010) reported that once cholesterol reaches the inner mitochondrial membrane, it is immediately converted to pregnenolone. Pregnenolone will then leave the mitochondria to the smooth endoplasmic reticulum, where it will be converted to progesterone (Svechnikov et al., 2010).
(2014) reported out of in vitro and in vivo study with mice, de novo synthesis of steroid (pregnenolone) by lymphocytes T-helper (th2), resulting in reduction of cell proliferation and immunosuppression.
Simultaneous radioimmunoassay of progesterone, androst-4-enedione, pregnenolone, dehydroepiandrosterone and 17-hydroxyprogesterone in specific regions of human brain.
The steroidal thiosemicarbazones 1-4 were obtained by reacting estrone and pregnenolone or their ester with thiosemicarbazide and then the reaction of compounds 1-4 with Cu[Cl.sub.2] x 2[H.sub.2]O gave steroidal copper (Cu (II)) complexes 5-8 as a mixture of (R)- and (S)-configuration isomers, respectively.
These metabolites were 2-oxo-3-methylvaleric acid, 3-hydroxy-DL-kynurenic acid, vinylacetylglycine, pregnenolone, nitrotyrosine, 1-methyl adenosine, oxoadipic acid, glyceric acid, citric acid, and isobutyric acid.