Immunomodulatory 7-hydroxylated metabolites of dehydroepiandrosterone are present in human semen

Seminal fluid represents a milieu enabling spermatozoa to break the ovum me mbrane and suppress its immune response and, at the same time. to protect m ale germ cells against infects. Among constituents of the seminal fluid var ious steroids, including dehydroepiandrosterone (DHEA) and its sulphate. Me rl detected. With respect to immunomodulatory and antioxidative properties of the latter steroids and its 7-hydroxylated metabolites. believed to be a t least in some instances the locally active species, their presence in sem inal fluid is of particular interest. Here for the first time unconjugated 3 beta ,7 alpha -dihydroxy-5-androsten-17-one (7 alpha -OH-DHEA) and its 7 beta -hydroxyisomer have been detected and quantified in semen. Eight semen samples were extracted with diethyl ether and Following evaporation and so lvent partition both isomers were detected by gas chromatography mass fragm entometry using the ions miz 358 and 343 for quantification. Another portio n was separated by HPLC and in the fractions corresponding to 7-OH-DHEA iso mers the steroids were measured by recently developed specific radioimmunoa ssays (RIA). Mean concentrations of 7-OH-DHEA as measured by RIA amounted 5 .75 +/- 1.29 and 5.39 +/- 0.75 nmol/l (mean +/- SEM) for 7 alpha- and 7 bet a -OH-DHEA. respectively. (C) 2001 Elsevier Science Ltd. All rights reserve d.