title: Seminal plasma alpha-glucosidase activity and male infertility.
abstract: Measurement of alpha-glucosidase (alpha-GLUC) activity by means of a simple colorimetric test using a commercial kit (EpiScreen; FertiPro, Lotenhulle, Belgium) yielded results that were strongly correlated with the values obtained for the neutral iso-enzyme measured by a fluorimetric reference method (r=0.85, P=0.003, n=13). The former method was characterized by a low intra- and inter-coefficient of variation (6.6 and 4.3% respectively). Vasectomized men with azoospermia (n=27) had a significantly lower alpha-GLUC activity in semen than vasectomized men with residual spermatozoa present (n=11, P < 0.01) and men with azoospermia of primary testicular origin (n=33, P < 0.01). Receiver operating curve (ROC) analysis showed alpha-GLUC measurement to be reasonably accurate in differentiation between cases with obstructive versus testicular azoospermia at criterion value 13.5 U/l (sensitivity=82%, specificity= 70%). In cases with spermatozoa present, alpha-GLUC activity and output per ejaculate were positively correlated with sperm concentration (r=0.53 and 0.38, n=472), linear velocity (r=0.35 and 0.30, n=224), curvilinear velocity (r=0.32 and r=0.29, n=224), semen adenosine triphosphate (r=0.35 and 0.26, n=64), the concentration of 5alpha-dihydrotestosterone (r=0.31 and 0.29, n=74), and gamma-glutamyltransferase activity (r=0.62 and 0.32, n=275) in seminal plasma. The activity of alpha-GLUC was inversely correlated with ROS generation after 12-myristate, 13-acetate phorbol ester stimulation (r=-0.27, n=104), and both alpha-GLUC activity and total output were inversely correlated with the concentration of peroxidase-positive white blood cells among samples with > or =1x10(6)/ml of these cells (r=-0.30 and -0.19, n=165). It is concluded that simple photometric measurement of alpha-GLUC activity in seminal plasma reflects the functional state of the epididymis and may be helpful for the differential diagnosis of certain cases with azoospermia.
authors.affiliation: Assiut University Hospital, Department of Dermatology and Andrology, Egypt.
authors.forename: A M
authors.initials: AM
authors.lastname: Mahmoud
authors.forename: J
authors.initials: J
authors.lastname: Geslevich
authors.forename: J
authors.initials: J
authors.lastname: Kint
authors.forename: C
authors.initials: C
authors.lastname: Depuydt
authors.forename: L
authors.initials: L
authors.lastname: Huysse
authors.forename: A
authors.initials: A
authors.lastname: Zalata
authors.forename: F H
authors.initials: FH
authors.lastname: Comhaire
mesh_terms: D003124:Colorimetry; D006801:Humans; D007248:Infertility, Male / Q000201:enzymology*; D008297:Male; D009845:Oligospermia / Q000175:diagnosis / Q000201:enzymology / Q000209:etiology; D012372:ROC Curve; D012661:Semen / Q000201:enzymology*; D012680:Sensitivity and Specificity; D014659:Vasectomy; D000520:alpha-Glucosidases / Q000378:metabolism*; D005723:gamma-Glutamyltransferase / Q000378:metabolism
chemical_list: D005723:gamma-Glutamyltransferase; D000520:alpha-Glucosidases