title: Expression of aromatase in human ejaculated spermatozoa: a putative marker of motility.
abstract: Cytochrome p450 aromatase (p450arom) is a key enzyme responsible for the irreversible transformation of androgens into estrogens. In the present study, we have analysed the ability of human ejaculated spermatozoa to produce estrogens and for that purpose we have looked for the expression of specific aromatase transcript and protein. We have confirmed the presence of p450arom transcript in all normospermic purified samples by nested PCR. The sequence of PCR products from purified spermatozoa shares 98% identity with published human p450arom sequence. Using a semi-quantitative approach, we have observed in immotile sperm a significant decrease (28%) of the aromatase/glyceraldehyde-3-phosphate dehydrogenase ratio compared with the motile sperm fraction. On Western blot with a monoclonal antibody directed against aromatase, we have detected two bands (53 and 49 kDa) in microsome preparations from purified spermatozoa. In total protein extracts of purified spermatozoa (with and without cytoplasmic droplets), we have only found the aromatase as a 49 kDa band with a stronger intensity when cytoplasmic droplets are present. Moreover, the band seems to be weaker in immotile spermatozoa (with and without cytoplasmic droplets). Our data demonstrate the expression of aromatase both in terms of mRNA and protein in each sample of human purified spermatozoa and in addition, our results suggest that aromatase could be concerned with the acquisition of sperm motility.
authors.affiliation: UPRES EA 2608-USC INRA, University-IRBA, Cedex, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Lambard
authors.forename: Isabelle
authors.initials: I
authors.lastname: Galeraud-Denis
authors.forename: Hélène
authors.initials: H
authors.lastname: Bouraïma
authors.forename: Sonia
authors.initials: S
authors.lastname: Bourguiba
authors.forename: Anne
authors.initials: A
authors.lastname: Chocat
authors.forename: Serge
authors.initials: S
authors.lastname: Carreau
mesh_terms: D000328:Adult; D001141:Aromatase / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004542:Ejaculation; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013081:Sperm Motility / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000201:enzymology*
chemical_list: D001141:Aromatase