Low seminal zinc bound to high molecular weight proteins in asthenozoospermic patients: evidence of increased sperm zinc content in oligoasthenozoospermic patients.
Total seminal zinc concentration, seminal zinc fraction bound to high molecular weight proteins (HMW-Zn%) and zinc content in spermatozoa were assayed in the ejaculates of 90 asthenozoospermic patients subdivided into two study groups: normoasthenozoospermics (group I: n = 50) and oligoasthenozoospermics (group II: n = 40). The zinc concentrations of patients were compared with those of a control group of donors showing normal semen parameters. All samples were also investigated for their sperm membrane functional integrity by the hypo-osmotic swelling test (HOS). The results showed normal total zinc concentrations but very low HMW-Zn% values (P < 0.001) in seminal plasma of the two groups of asthenozoospermic patients compared to the controls. Furthermore higher zinc amounts (P < 0.001) were measured in spermatozoa of oligoasthenozoospermic patients compared to group I and to the control group. Oligoasthenozoospermics also displayed a lower HOS score (P < 0.001) compared to the other two groups. These data suggest that the increased unbound seminal zinc could contribute to the decrease of sperm motility in normoasthenozoospermic and oligoasthenozoospermic patients. A further impairment in sperm motility could occur in the oligoasthenozoospermic patients where the increase of seminal free zinc was followed by a major zinc uptake by spermatozoa. The higher intrasperm zinc content in these patients could be a reflection of their low sperm membrane functionality.
Carpino
A
A
Dipartimento di Biologia Cellulare, Università degli Studi della Calabria, Italy.
Siciliano
L
L
Petroni
M F
MF
De Stefano
C
C
Aquila
S
S
Andó
S
S
Petrone
M F
MF
D000328:Adult; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D008970:Molecular Weight; D009845:Oligospermia / Q000378:metabolism*; D009997:Osmotic Pressure; D012661:Semen / Q000378:metabolism*; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology*; D013094:Spermatozoa / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism*
D015032:Zinc