Novel lipoidal derivatives of pregnenolone and dehydroepiandrosterone and absence of their sulfated counterparts in rodent brain.
A new sample preparation method coupled to GC-MS analysis was developed and validated for quantification of sulfate esters of pregnenolone (PREG-S) and dehydroepiandrosterone (DHEA-S) in rat brain. Using a solid-phase extraction recycling protocol, the results show that little or no PREG-S and DHEA-S (<1 pmol/g) is present in rat and mouse brain. These data are in agreement with studies in which steroid sulfates were analyzed without deconjugation. We suggest that the discrepancies between analyses with and without deconjugation are caused by internal contamination of brain extract fractions, supposed to contain steroid sulfates, by lipoidal forms of PREG and DHEA (L-PREG and L-DHEA, respectively). These derivatives can be acylated very efficiently with heptafluorobutyric anhydride and triethylamine, and their levels in rodent brain (approximately 1 nmol/g) are much higher than those of their unconjugated counterparts. They are distinct from fatty acid esters, and preliminary data do not favor structures such as sulfolipids or sterol peroxides. Noncovalent interactions between steroids and proteolipidic elements, such as lipoproteins, could account for some experimental data. Given their abundance in rodent brain, the structural characterization and biological functions of L-PREG and L-DHEA in the central nervous system merit considerable attention.
Liere
Philippe
P
Institut National de la Santé et de la Recherche Médicale U488, 94276 Kremlin-Bicêtre, France. liere@kb.inserm.fr
Pianos
Antoine
A
Eychenne
Bernard
B
Cambourg
Annie
A
Liu
Suya
S
Griffiths
William
W
Schumacher
Michael
M
Sjövall
Jan
J
Baulieu
Etienne-Emile
EE
D000818:Animals; D001921:Brain / Q000378:metabolism*; D003687:Dehydroepiandrosterone / Q000031:analogs & derivatives / Q000378:metabolism*; D019314:Dehydroepiandrosterone Sulfate / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D008297:Male; D011284:Pregnenolone / Q000031:analogs & derivatives / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
C018370:pregnenolone sulfate; D003687:Dehydroepiandrosterone; D019314:Dehydroepiandrosterone Sulfate; D011284:Pregnenolone