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)

Spermatic enzymes (fructose, alkaline phosphatase, gammaglutamyl transferase, alpha-glucosidase, dipeptydil aminopeptidase IV) were measured in 200 patients with secretory-toxic infertility. It is shown that in some variants of infertility changes in the levels of spermatic enzymes are compensatory. These changes may also reflect qualitative characteristics of spermatozoa.
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PMID:[Changes in the enzyme level of the sperm of men with infertility]. 957 5

Low alpha-glucosidase activity in seminal plasma is a marker of epididymal obstruction. The criterion standard for determining activity is the epididymal specific method, whereby the neutral iso-enzyme, specifically produced by the epididymis, is measured. A kit that determines total alpha-glucosidase activity (neutral iso-enzyme and the acid iso-enzyme originating from the prostate) has become available. The objective of the laboratory-based study was to compare alpha-glucosidase activity values measured by both the EpiScreen and the epididymal specific method, to determine if the kit may provide reliable results to substitute the neutral iso-enzyme specific method in the routine clinical setting. The neutral iso-enzyme activity according to both methods was measured in seminal plasma of 23 post-vasectomy and 24 normozoospermic patients. Significant differences (P < 0.05) were found between the activities measured according to both methods, but these differences pertained mostly to high values (> 40 mU ejaculate-1), which was not clinically significant. In conclusion, the epididymal specific method is best suited for research purposes, but the EpiScreen kit is convenient for routine use in infertility clinics.
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PMID:A comparative study of the EpiScreen kit and a conventional method for the determination of seminal alpha-glucosidase activity. 963 92

The origin of seminal leucocytes and their biological significance were investigated in 76 whole ejaculate samples and 27 split ejaculate samples, obtained from patients attending the Zimbabwe Family Planning Council's Spilhaus Infertility Clinic at Harare. The leucocytes were more prevalent in fractions 1 and 2 than in fraction 3, implying that the testis, epididymis and prostate are the major sources of seminal leucocytes. The contribution from the seminal vesicles was minimal. An inverse relation is apparent between leucocyte count and sperm count (p < 0.01). The percentage of abnormal sperms was higher (p < 0.05) and the sperm motility poorer in leucocytospermic samples (p < 0.01). Fructose, the seminal vesicular marker, citric acid, the prostatic marker and alpha-glucosidase, the epididymal marker were not decreased in leucocytospermia. It is concluded that the epididymis and prostate are the major contributors of granulocytes in semen. Leucocytospermia affects sperm morphology and sperm motility but not the accessory sex gland functions. Probably these cytotoxic effects are mediated by hydrogen peroxide due to activation of seminal leucocytes. However, the presence of leucocytospermia in normozoospermic samples is indicative of the possible peaceful coexistence of leucocytes and sperms.
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PMID:Study on the origin of seminal leucocytes using split ejaculate technique and the effect of leucocytospermia on sperm characteristics. 987 48

Results from recent animal models with implications for putative human male contraceptives acting on the epididymis are reviewed. Inducing sterility by enhancing sperm transport through the epididymis has not been achieved. The induction of infertility in males of several species is easier to achieve by direct actions of drugs on sperm function (e.g. inhibition of sperm-specific isoenzymes of the glycolytic pathway by chloro-compounds) than by indirectly reducing amounts of epididymal secretions normally present in high concentration (e.g. alpha-glucosidase, L-carnitine). The former show promise for the clinic since human spermatozoa are susceptible to inhibition. On the other hand, the infertile male mice of the c-ros knock-out model demonstrate the influence of even a small region of the epididymis on fertility, so that targeting the as yet unknown epididymal factors presumably secreted in limiting amounts by this epididymal segment, is a new lead for a contraceptive. Targeting a specific sperm protein acquired in the testis, but depleted in the epididymis by toxicants that induce rapid infertility, may also lead to the discovery of new contraceptives, but these will require developing new means of organ-specific delivery of contraceptive drugs.
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PMID:Recent biochemical approaches to post-testicular, epididymal contraception. 1033 18

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

The induction of infertility in males of several species through epididymal interference is more difficult to achieve by reduction of the amounts of epididymal secretions (eg alpha-glucosidase, L-carnitine) or immunological interference with secreted proteins (eg D/E, P34H, P26h) than by direct actions of drugs on sperm function (eg inhibition of glyceraldehyde 3-phosphate dehydrogenase by chloro-compounds). The latter approach holds promise for mankind as human sperm are susceptible to glycolytic inhibition. Future contraceptive developments may arise from production of targeted inhibitors, research on the displacement of sperm proteins in the epididymis and interference with sperm plasma membrane ion channels.
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PMID:Approaches to post-testicular contraception. 1122 1

A comparative study was carried out in the andrology clinic, Parirenyatwa Hospital, Harare, Zimbabwe, to investigate the sperm characteristics and accessory sex gland functions in HIV-infected individuals. Sixty-two patients with infertility problems who attended the clinic were requested to donate semen and blood after consent was obtained. HIV antibodies in paired semen and blood samples, sperm morphology, sperm count, sperm motility, seminal leucocytes, seminal fructose, seminal neutral alpha-glucosidase, and citric acid were analyzed. Nine out of 31 blood samples tested positive, while 21 out of 62 semen samples were positive for HIV. Leucocytospermia was associated with HIV-seropositive men (p < .01). The accessory sex gland function, as evaluated by biochemical markers, was not affected in HIV-seropositive men. HIV causes impairment of sperm motility by activating seminal leucocytes, which in turn induce oxidative stress on the sperm. Leucocytospermia is almost always present in HIV-seropositive men.
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PMID:Sperm characteristics and accessory sex gland functions in HIV-infected men. 1129 70

Gossypol, a pigment found in cottonseed that has recently been shown to have antifertility properties, inhibited the activity of 3 intestinal brush border enzymes in a concentration-dependent manner. Suspensions of rat intestinal mucosa were incubated with various concentrations of gossypol for 45 minutes and then washed. At a concentration of 6 mg per gm mucosa, gossypol inhibited the activities of alkaline phosphatase, maltase, and sucrase by 57, 73, and 77%, respectively. Gossypol is a bifunctional agent, capable of cross-linking amino acid side chains, and its action on brush-border enzymes may be due to this mechanism. Recent investigations have demonstrated that rats fed a diet of 10-15 mg of gossypol/day/kg of body weight exhibit reduced fertility. This study suggests that a partial inhibition of brush-border enzymes may occur at doses used to cause infertility. Such a side effect should be considered in studies and treatments utilizing a gossypol diet.
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PMID:Inactivation of intestinal brush-border enzymes by gossypol. 1228 3

The present study was designed to determine the response of human epididymis, seminal vesicles and prostate function after a 5-day course of clomiphene citrate in men attending an infertility service. In 45 men, the secretions of the epididymis, seminal vesicles and prostate were assessed by measurements of seminal alpha-glucosidase, fructose and acid phosphatase, respectively. Subjects were classified as normal or abnormal: abnormal men were defined as those who either had history of a sexually transmitted disease (STD), leukocytospermia, hypoandrogenism, or a low response of Leydig cells to clomiphene stimulation; and normal subjects were those who did not have these conditions. Mean serum testosterone luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels were significantly increased after the short course with clomiphene citrate. After clomiphene citrate stimulation, the men in the normal group showed significantly increased marker levels of the seminal vesicles (P < 0.02) and prostate (P < 0.05), but not of the epididymis (P : NS). Men classified as abnormal showed no response according to the markers of the seminal vesicles and epididymis. Men with history of STD and abnormal basal values of acid phosphatase did not respond to the treatment. Men with history of STD but normal basal values of seminal acid phosphatase increased significantly in their levels of seminal acid phosphatase after clomiphene stimulation (P < 0.02). Multivariate analysis showed that the basal serum testosterone level was the only variable in predicting the probability of response to the clomiphene in terms of true-corrected seminal fructose, seminal acid phosphatase and seminal alpha-glucosidase levels. In fact, a high response of the seminal vesicles was observed in men with the highest basal serum testosterone levels (0.45 +/- 0.17; coefficient of regression +/- standard error; P < 0.018). However, a high response in terms of seminal acid phosphatase (P < 0.004) or alpha-glucosidase (P < 0.037) was observed in men with low basal serum testosterone levels. In conclusion, in the normal men, true-corrected fructose and acid phosphatase but not alpha-glucosidase in semen increased after duplicate androgen stimulation. An absence of response was observed in cases with history of STD/leukocytospermia or hypoandrogenism.
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PMID:Basal serum testosterone as an indicator of response to clomiphene treatment in human epididymis, seminal vesicles and prostate. 1239 89

A history of urogenital inflammation occurs in 5-12% of men attending infertility clinics. Usually, infection has a detrimental effect on sperm quality by reducing concentration and motility, and possibly affecting the number of morphological normal spermatozoa. In addition, infection may be the source of auto-antibodies against spermatozoa, found in about 8% of the infertile male population. In contrast to the situation in women, there is no clear evidence that male accessory gland infections can result in epididymal blockage or vassal obstruction, with the exception of genital tuberculosis. Although Chlamydia trachomatis is a well-documented source of chronic prostatitis, the infection does not seem to cause obstruction of the reproductive tract, as it does in women. If male urogenital infection causes obstruction it is most likely located at the level of the ejaculatory ducts. Chronic prostatitis has been proved to cause scarring of the prostatic and ejaculatory ducts, resulting in low seminal volume with low fructose and alpha-glucosidase. Many of these men present with severe oligozoospermia or azoospermia, normal size testis and normal gonadotrophins. We performed an excisional testicular biopsy in all men presenting with <1 million spermatozoa per millilitre and found that 39 of 78 (50%) had a normal spermatogenesis. A history of male accessory genital infection was found in 12% of the men and 10% had abnormalities found on transrectal ultrasound of the prostate (like oedema, dilatation of the seminal vesicles and ejaculatory ducts) intraprostatic calcifications and dilatation of the periprostatic venous plexus. Ejaculatory duct obstruction is a common cause of male infertility and infections are present in at least 22-50% of these men. Transurethral resection of the ejaculatory ducts may result in a significant improvement of the sperm quality and in spontaneous pregnancies in up to 25% of the couples. In case of failure sperm aspiration from the epididymis and intracytoplasmic sperm injection is the treatment of choice.
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PMID:Inflammatory-associated obstructions of the male reproductive tract. 1453 64


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