Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A specific assay based on the spectrophotometric determination of the release of p-nitrophenol from p-nitrophenol-alpha-D-glucopyranoside by maltase has been used to measure the activity of the enzyme in seminal plasma and in homogenates of accessory reproductive organs. Specific activity of seminal plasma maltase was 467 muU/mg of proteins in 68 fertile men, decreased significantly in varicocele (296 muU/mg), in azoospermia (246 muU/mg) and in vasectomized patients (62 muU/mg). Application of ion exchange chromatography on DEAE-Sephadex A-50 columns led to the demonstration that maltase activity of seminal plasma and of cytosols from normal reproductive organs was recovered in three different fractions. Maltase activity is thus frequently decreased in infertility.
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PMID:Origin of maltase and variations in infertile men. 36 66

Obstruction of the vas deferens has been screened for, using the alpha-glucosidase reaction in seminal plasma as previously described by Comhaire. Eighteen patients with azoospermia were studied. The result showed positive reaction in 17 patients (95.0%) and only a weak yellow reaction in 1 patient. The results did not corroborate the working hypothesis that the azoospermia was due to obstruction of the vas deferens. The implications of this findings in the management of male infertility in Nigeria are discussed.
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PMID:Screening for obstruction of the vas deferens in Nigerian men with azoospermia using the alpha-glucosidase reaction in semen. 130 86

Seminal alpha-glucosidase has been used clinically as a marker of epididymal function. In this study enzyme inhibitors were used to increase the specificity of the human seminal alpha-glucosidase assay and improve its diagnostic value as an indicator of distal epididymal occlusion in cases of azoospermia. Sodium dodecylsulphate was added to the sample to eliminate the interfering acid isoenzyme secreted by the prostate gland, and castanospermine was used with semen pools to provide a semen blank for the assay by eliminating non-glucosidase-regulated degradation of the substrate. With both inhibitors included in the assay, glucosidase activity in semen samples from 17 fathers was measured to provide reference values for the clinic (lower threshold 18 mU per ejaculate). With the improved assay glucosidase was non-detectable in 8 out of 11 cases of proven and 5 out of 8 cases of suspected ductal obstruction; other azoospermic patients with distal occlusion had values below 11 mU per ejaculate.
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PMID:Improvement in the assessment of human epididymal function by the use of inhibitors in the assay of alpha-glucosidase in seminal plasma. 220 50

L-carnitine, alpha,1-4-glucosidase, and glycerylphosphorylcholine were measured in seminal plasma of a selected group of azoospermic men and in an unselected group of oligozoospermic men. In vasectomized subjects the epididymal indices (mean +/- standard error: L-carnitine, 276.9 +/- 27.5 nmol/ejaculate; alpha-glucosidase, 1.2 +/- 0.1 U/ejaculate; and glycerylphosphorylcholine, 1.5 +/- 0.2 mumol/ejaculate) were always below the normal range of fertile subjects (1757.4 +/- 76.7 nmol/ejaculate; 16.4 +/- 0.9 U/ejaculate; and 17.3 +/- 0.7 mumol/ejaculate, respectively). On the contrary in a large number of patients affected by azoospermia because of seminiferous tubular damage (750.4 +/- 83.6 nmol/ejaculate; 6.8 +/- 0.9 U/ejaculate; and 6.1 +/- 0.6 mumol/ejaculate; respectively) and in a few oligozoospermic subjects (1193.7 +/- 72.3 nmol/ejaculate; 10.3 +/- 0.7 U/ejaculate; and 10.8 +/- 0.7 mumol/ejaculate; respectively) the epididymal indices were found in the range of vasectomized subjects, showing an association between seminiferous tubular lesion and epididymal dysfunction. In conclusion, in spite of the low levels of epididymal indices found in patients with obstructive azoospermia, the presence of a large number of subjects with seminiferous tubular lesions without obstruction with similar low values of L-carnitine, alpha-glucosidase, and glycerylphosphorylcholine reduces the usefulness of these indices in differential diagnosis of azoospermia.
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PMID:Simultaneous measurement of seminal L-carnitine, alpha,1-4-glucosidase, and glycerylphosphorylcholine in azoospermic and oligozoospermic patients. 310 88

Azoospermic semen was obtained from 39 vasectomized men and 93 patients consulting for infertility. The latter underwent bioclinical investigations including measurement of plasma FSH and testicular biopsies. Carnitine content and alpha-glucosidase activity in semen samples were measured. The activity of alpha-glucosidase was determined systematically by a semiquantitative microtechnique and was verified by a spectrophotometric assay. A positive correlation was observed between carnitine and alpha-glucosidase activity. Both parameters were severely diminished in semen from the vasectomized men and the patients suffering from a complete obstruction of the genital tract. Enzyme activity was the most discriminant parameter in terms of sensitivity and specificity. The measurement of alpha-glucosidase in semen is a simple and sensitive method for determining the origin of azoospermia when used in conjunction with assays for plasma FSH.
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PMID:Alpha-glucosidase as a specific epididymal enzyme marker. Its validity for the etiologic diagnosis of azoospermia. 352 16

Semi-quantitative estimations of the activities of 65 enzymes were studied for cases of azoospermia in an attempt to correlate the seminal enzyme profile with the origin of the azoospermia. One single enzyme--alpha-glucosidase--showed variation. All other specificities tested gave identical results for all the azoospermic samples and for normal controls. The alpha-glucosidase activity that is present in normal semen was absent from samples from patients with azoospermia associated with a complete obstruction of the genital tract, and also from all semen samples from vasectomized subjects. This enzyme appears to be secreted by the epididymis, and the activity present in azoospermic semen can provide information concerning the origin of the azoospermia and the functional state of the epididymis. Positive but reduced alpha-glucosidase activity appears to be frequently associated with inflammatory disease. The consequences of these findings are discussed.
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PMID:Enzymes in the seminal plasma from azoospermic men: correlation with the origin of their azoospermia. 679 4

Neutral alpha-glucosidase activity was measured in seminal plasma of 30 patients consulting for infertility with a variety of disorders, and compared with 25 normal controls. Significantly more of the study populations (asthenozoospermia, 4/6; oligozoospermia, 3/5; azoospermia 8/15) had a neutral alpha-glucosidase activity less than 10 mIU/mL as compared with control samples (3/25). Also the mean (+/- SD) neutral alpha-glucosidase activity in patients with asthenozoospermia (11.7 +/- 9.2) oligozoospermia (11.3 +/- 7.2), and post vasectomy azoospermia (5.3 +/- 3.4) was significantly (p < .05) less than ejaculate from controls (21.2 +/- 14). A seminal alpha-glucosidase level of 10 mIU/mL appears to be a useful discriminatory marker in the diagnosis of epididymal obstruction or dysfunction.
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PMID:New discriminatory level for glucosidase activity to diagnose epididymal obstruction or dysfunction. 855 28

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.
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PMID:Seminal plasma alpha-glucosidase activity and male infertility. 957 18

Based on a comparative study in a group of healthy men and men suffering from oligospermia and azoospermia, the authors consider it useful to examine FSH, LH, PRL and testosterone serum levels for possible evidence of testicular hypofunction and for detection of stress situations associated with raised PRL levels. As to seminal plasma, the authors consider it useful and relevant to assess citric acid levels, total acid phosphatases and in particular fructose with alpha-glucosidase.
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PMID:[Results of a study of serum hormones and biochemical findings in seminal plasma in subfertile men examined at the Clinic for Gynecology and Obstetrics in Olomouc 1995-1996]. 960 Jan 67

alpha-Glucosidase is a normal constituent of human semen, produced mainly in the epididymis. It is significantly correlated to sperm count. Its activity is low in cases of epididymal obstruction. We evaluated alpha-glucosidase activity in 653 semen samples of patients, who attended our department for marital infertility, with respect to associations to clinical and other seminal parameters. The normal range (mean +/- 2 SD) in samples with normal parameter values was 7.2-46.4 mU ml-1. The determination in patients with azoospermia revealed mean values of 7.7 +/- 9.5 mU ml-1 in obstructive azoospermia, and 15.8 +/- 11.5 mU ml-1 in nonobstructive azoospermia. The difference was not statistically significant in that the sensitivity of determination with respect to the presence of obstruction was only 0.66, and the specificity 0.83. A significant correlation (r = 0.34) of alpha-glucosidase activity with log sperm count was observed. The mean alpha-glucosidase activity was not significantly different in groups formed according to sperm motility, according to leucocyte count or according to semen volume. A difference between smokers and nonsmokers with comparable sperm count, as reported in the literature, did not occur. We conclude from our results that the determination of alpha-glucosidase activity does not give additional information of the fertility status exceeding that of other clinical investigations or parameters of semen analysis.
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PMID:Why do we determine alpha-glucosidase activity in human semen during infertility work-up? 1052 38


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