Neutral α-glucosidase activity in mouse: a marker of epididymal function?

2007 ◽  
Vol 19 (4) ◽  
pp. 563 ◽  
Author(s):  
Ana C. Martini ◽  
Rosa I. Molina ◽  
Laura M. Vincenti ◽  
María E. Santillán ◽  
Graciela Stutz ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Food Restriction ◽  
Sperm Concentration ◽  
Secretory Activity ◽  
Spectrophotometric Analysis ◽  
Glucosidase Activity ◽  
Epididymal Maturation ◽  
Mouse Epididymis ◽  
Positive Controls

Neutral α-glucosidase (NAG) activity is considered a functional epididymal marker in several species. Unlike the rat, no NAG activity has been detected in mice. The aims of the present study were to evaluate NAG secretory activity (the supernatant of the incubated tissue) in mouse epididymis and to determine whether it could be used as a functional epididymal marker. Epididymides (whole or in parts) were incubated in the presence or absence of testosterone (10−5 m) and secretory NAG activity was compared with known positive controls. Furthermore, we compared enzyme activity in epididymides from well-fed and undernourished mice (50% food restriction for 21 days), a model that alters the epididymal maturation processes. Spectrophotometric analysis revealed NAG activity in mouse epididymis (22.6 ± 3.7 mU g–1 tissue; n = 4), being higher in the caput. NAG activity was statistically higher in the caput than in the corpus and in the cauda. No significant differences existed between the caput NAG activity and complete epididymis NAG activity. In undernourished mice, we confirmed changes in epididymal maturation observed previously (i.e. increased number of immature spermatozoa and diminution of the sperm concentration). Concordantly, the epididymides of undernourished mice exhibited decreased enzyme secretory activity, which increased to values similar to those seen in controls following incubation in the presence of testosterone (22.5 ± 2.6, 12.5 ± 1.0 and 22.4 ± 3.7 mU g–1 tissue, n = 9 in control (n = 7), undernourished (n = 9) and undernourished + testosterone groups (n = 9), respectively). In conclusion, NAG activity was detected in mouse epididymis. Although the present study supports the possibility of using NAG as an epididymal marker, more studies are necessary to effectively prove that NAG activity can be used as an epididymal marker.

Antibacterial Flavonoids Against Oral Bacteria of Enterococcus Faecalis ATCC 29212 from Sarang Semut (Myrmecodia pendans) and Its Inhibitor Activity Against Enzyme MurA

2019 ◽  
Vol 16 (3) ◽  
pp. 290-296 ◽  
Author(s):  
Dikdik Kurnia ◽  
Eti Apriyanti ◽  
Cut Soraya ◽  
Mieke H. Satari
Keyword(s):  
Enzyme Activity ◽  
Enterococcus Faecalis ◽  
Ethyl Acetate Fraction ◽  
Antibacterial Activities ◽  
Oral Bacteria ◽  
Diffusion Method ◽  
Enzyme Activity Assay ◽  
Antibacterial Compounds ◽  
Ic50 Values ◽  
Positive Controls

Background: A significant number of antibiotics are known to inhibit peptidoglycan synthesis in the cross-linking stage, while the drug fosfomycin is the only one known to inhibit MurA. Escalated antibiotic resistance has had an impact on the efficacy of fosfomycin, thus demanding the discovery of suitable substitutes with improved potential for MurA inhibition. The aim of this work is to isolate antibacterial compounds from Sarang Semut (Myrmecodia pendans) and to evaluate their antibacterial activity against pathogenic oral bacteria of Enterococcus faecalis ATCC 29212 and inhibitory activity against MurA enzyme. Methods: The antibacterial compounds from Sarang Semut were isolated by a bioactivity-guided separation method with various solvents and combination of column chromatography on normal and reverse phases. The compounds with concentrations of 1000 and 5000 ppm were assessed against E. faecalis ATCC 29212 by agar well diffusion method, with chlorhexidine and fosfomycin being used as positive controls. Results: Two antibacterial compounds isolated from Sarang Semut were identified as two new flavonoids derivates of 1 (10 mg) and 2 (4 mg). Both compounds were tested for antibacterial activities against E. faecalis. MIC values of compounds 1 and 2 were 8.15 and 8.05 mm at 1000 ppm and 8.62 and 8.55 mm at 5000 ppm, respectively. MBC values were 156 and 625 ppm for 1 and 625 and 2500 ppm for 2, respectively. In an inhibitory murA enzyme activity assay, compounds 1 and 2 were shown to inhibit the enzyme activity by IC50 values of 21.7 and 151.3 ppm. Conclusion: The study demonstrated that ethyl acetate fraction of Sarang Semut contained antibacterial flavonoids as active constituents that showed activity against E. faecalis. These results showed the plant’s potential in herbal medicine and the development of new antibacterial agent for pathogenic dental caries.

scholarly journals Gelatinases in Boar Seminal Plasma and Their Relation to Semen Indicators

2010 ◽  
Vol 79 (3) ◽  
pp. 491-496 ◽  
Author(s):  
Maja Zakošek Pipan ◽  
Marjan Kosec ◽  
Janko Mrkun ◽  
Petra Zrimšek
Keyword(s):  
Molecular Weight ◽  
Enzyme Activity ◽  
Seminal Plasma ◽  
Animal Species ◽  
Sperm Concentration ◽  
Gelatin Zymography ◽  
Motile Sperm ◽  
Molecular Weights ◽  
Simultaneous Identification ◽  
First Time

Matrix metalloproteinases were detected in reproductive tissues and seminal plasma of various animal species. The aim of this study was to determine for the first time the presence of gelatinases and metalloproteases in boar seminal plasma and to correlate the results with semen indicators. Gelatin zymography was used for simultaneous identification and measurement of gelatinase enzyme activity associated with their molecular weights. Several gelatinase forms were identified in seminal plasma of boars. Those that were stimulated by CaCl2 and inhibited by EDTA and phenanthroline were considered as metalloproteases. Negative correlation between semen indicators (sperm index, sperm concentration and concentration of progressive motile sperm) and the concentrations of metalloprotease at 78 kDa and 66 kDa means that higher values of semen indicators correlate with lower concentrations of these metaloproteases in seminal plasma. Gelatinases with molecular weight of 225, 78 and 66 kDa correlated with higher levels of acrosome damage. Samples with sperm index above 110 M/ml contained gelatinases of significantly lower band intensities at 78 and 66 kDa compared to samples with SI less than 110 M/ml. Bands with 225, 78 and 66 kDa are suggested to belong to a dimer of MMP-9, proMMP-2 and mature MMP-2.

Body mass index and human sperm quality: neither one extreme nor the other

2017 ◽  
Vol 29 (4) ◽  
pp. 731 ◽  
Author(s):  
E. M. Luque ◽  
A. Tissera ◽  
M. P. Gaggino ◽  
R. I. Molina ◽  
A. Mangeaud ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Sperm Quality ◽  
Sperm Count ◽  
Sperm Concentration ◽  
Normal Weight ◽  
Semen Parameters ◽  
Morbidly Obese ◽  
Epididymal Maturation ◽  
Increased Risk

The aim of the present study was to investigate the still contentious association between body mass index (BMI) and seminal quality. To this end, 4860 male patients (aged 18–65 years; non-smokers and non-drinkers), were classified according to BMI as either underweight (UW; BMI <20 kg m–2; n = 45), normal weight (NW; BMI 20–24.9 kg m–2; n = 1330), overweight (OW; BMI 25–29.9 kg m–2; n = 2493), obese (OB; BMI 30–39.9 kg m–2; n = 926) or morbidly obese (MOB; BMI ≥40 kg m–2; n = 57). Conventional semen parameters and seminal concentrations of fructose, citric acid and neutral α-glucosidase (NAG) were evaluated. The four parameters that reflect epididymal maturation were significantly lower in the UW and MOB groups compared with NW, OW and OB groups: sperm concentration, total sperm count (103.3 ± 11.4 and 121.5 ± 20.6 and vs 157.9 ± 3.6, 152.4 ± 2.7 or 142.1 ± 4.3 spermatozoa ejaculate–1 respectively, P < 0.05), motility (41.8 ± 2.5 and 42.6 ± 2.6 vs 47.8 ± 0.5, 48.0 ± 0.4 or 46.3 ± 0.6 % of motile spermatozoa respectively, P < 0.05) and NAG (45.2 ± 6.6 and 60.1 ± 7.9 vs 71.5 ± 1.9, 64.7 ± 1.3 or 63.1 ± 2.1 mU ejaculate-1 respectively, P < 0.05). Moreover, the percentage of morphologically normal spermatozoa was decreased in the MOB group compared with the UW, NW, OW and OB groups (4.8 ± 0.6% vs 6.0 ± 0.8%, 6.9 ± 0.1%, 6.8 ± 0.1 and 6.4 ± 0.2%, respectively; P < 0.05). In addition, men in the MOB group had an increased risk (2.3- to 4.9-fold greater) of suffering oligospermia and teratospermia (P < 0.05). Both morbid obesity and being underweight have a negative effect on sperm quality, particularly epididymal maturation. These results show the importance of an adequate or normal bodyweight as the natural best option for fertility, with both extremes of the BMI scale as negative prognostic factors.

scholarly journals Histoplasma capsulatum Strain Variation in Both H Antigen Production and β-Glucosidase Activity and Overexpression of HAG1 from a Telomeric Linear Plasmid

1999 ◽  
Vol 67 (7) ◽  
pp. 3312-3316 ◽  
Author(s):  
Kimber L. Fisher ◽  
George S. Deepe ◽  
Jon P. Woods
Keyword(s):  
Enzyme Activity ◽  
Protein Expression ◽  
Histoplasma Capsulatum ◽  
Pathogenic Fungus ◽  
Class Ii ◽  
Multicopy Plasmid ◽  
Class Iii ◽  
Glucosidase Activity ◽  
Culture Supernatants ◽  
H Protein

ABSTRACT The H antigen of the dimorphic fungal pathogen Histoplasma capsulatum was first described over 40 years ago. It is a secreted glycoprotein that is immunogenic during infection. Recent cloning of the H antigen gene (HAG1) indicated sequence homology with genes for fungal β-glucosidases. To understand the biological role of this immunodominant antigen in H. capsulatum, enzymatic assays were performed to determine whetherH. capsulatum contained a β-glucosidase enzyme activity and whether this activity was encoded by the HAG1 gene. Substrate gels with H. capsulatum culture supernatants revealed β-glucosidase activity near the predicted mobility of the H antigen. Quantitative microtiter plate assays revealed marked differences in secreted β-glucosidase activities from three H. capsulatum restriction fragment length polymorphism (RFLP) classes, with RFLP class II strains displaying high levels of enzyme activity, in contrast to the low levels of activity exhibited by class I and III strains. Immunoblotting of culture supernatants with an H antigen-specific antiserum demonstrated differences in H protein expression levels between the H. capsulatum classes, with a correlation between secreted enzyme activity and H protein levels. We took advantage of these class differences to demonstrate multicopy plasmid H gene overexpression by transformation of an HAG1plasmid into H. capsulatum. Both a class II strain (G217Bura5-23) and a class III strain (G184ASura5-11) transformed with the telomeric overexpression plasmid pMAD401 displayed increased levels of β-glucosidase enzyme activity and H protein expression compared to the levels in control transformants containing only the single genomic copy of HAG1. This is the first demonstration of telomeric plasmid-mediated protein overexpression in this pathogenic fungus, and the findings support the identification of the H antigen as a β-glucosidase.

Insulin release transduction mechanism through acid glucan 1,4-α-glucosidase activation is Ca2+ regulated

1998 ◽  
Vol 274 (3) ◽  
pp. E459-E468 ◽  
Author(s):  
Albert Salehi ◽  
Henrik Mosén ◽  
Ingmar Lundquist
Keyword(s):  
Enzyme Activity ◽  
Insulin Secretion ◽  
Insulin Release ◽  
Similar Increase ◽  
Glucosidase Activity ◽  
Intracellular Ca ◽  
Low Glucose ◽  
Perifused Islets ◽  
Glucose Stimulated Insulin Secretion ◽  
Induced Changes

An important signal involved in glucose-stimulated insulin secretion is transduced through the action of a lysosomal acid, glucan 1,4-α-glucosidase. We investigated the Ca2+ dependency of this enzyme activity in relation to insulin release. In isolated islets, increased levels of extracellular Ca2+induced a large increase in acid glucan 1,4-α-glucosidase activity accompanied by a similar increase in insulin release at both substimulatory and stimulatory concentrations of glucose. At low glucose the Ca2+ “inflow” blocker nifedipine unexpectedly stimulated enzyme activity without affecting insulin release. However, nifedipine suppressed45Ca2+outflow from perifused islets at low glucose and at Ca2+ deficiency when intracellular Ca2+ was mobilized by carbachol. This nifedepine-induced retention of Ca2+ was reflected in increased acid glucan 1,4-α-glucosidase activity. Adding different physiological Ca2+ concentrations or nifedipine to islet homogenates did not increase enzyme activity. Neither selective glucan 1,4-α-glucosidase inhibition nor the ensuing suppression of glucose-induced insulin release was overcome by a maximal Ca2+ concentration. Hence, Ca2+-induced changes in acid glucan 1,4-α-glucosidase activity were intimately coupled to similar changes in Ca2+-glucose-induced insulin release. Ca2+ did not affect the enzyme itself but presumably activated either glucan 1,4-α-glucosidase-containing organelles or closely interconnected messengers.

Inhibition by nojirimycin and 1-deoxynojirimycin of microsomal glucosidases from calf liver acting on the glycoprotein oligosaccharides Glc1–3Man9GlcNAc2

1982 ◽  
Vol 2 (11) ◽  
pp. 899-906 ◽  
Author(s):  
Harald Hettkamp ◽  
Ernst Bause ◽  
Günter Legler
Keyword(s):  
Enzyme Activity ◽  
Initial Velocity ◽  
Ph Dependence ◽  
Detergent Concentration ◽  
Free Peptide ◽  
Glucosidase Activity ◽  
Significant Difference ◽  
Lower Extent ◽  
Triton X ◽  
Hydrolysis Of

Particulate membrane fractions from calf liver catalyze the release of glucose from GlcNAc2-Man9-Glc1–3-oligosaccharides. Maximal oligosaccharide-glucosidase activity was obtained at pH 6.2 and a detergent concentration of 0.5% Triton X-100. This activity could be distinguished from non-specific α-glucosidase activity on the basis of different pH-dependence and lack of activation by detergent. The relative rates for the hydrolysis of the Glc3-, Glc2-, and Glcl-oligosaccharide, estimated from the initial velocity, was 1: 12: 3. There is no significant difference in the enzyme activity towards free, peptide-bound, or lipid-linked oligosaccharide. Nojirimycin and l-deoxynojirimycin were strong inhibitors of microsomal oligosaccharide-glucosidases. Hydrolysis of GIc3-oligosaccharide was inhibited by 50% at concentrations of 0.16 mM and 2 μM, respectively. Hydrolysis of the Glc2- and Glc1-oligosaccharide was inhibited to a somewhat lower extent, suggesting the presence of at least two glucosidases, one acting on Glc3- and one acting on Glc1- and Glc2-oligosaccharide.

Stability of induced α-glucosidase activity in the absence of inducer

1969 ◽  
Vol 47 (7) ◽  
pp. 677-684 ◽  
Author(s):  
Robert G. Bell
Keyword(s):  
Protein Synthesis ◽  
Enzyme Activity ◽  
Energy Production ◽  
Yeast Cells ◽  
Glucose Medium ◽  
Inhibit Protein Synthesis ◽  
Original Activity ◽  
Glucosidase Activity ◽  
Initial Rise ◽  
Purine Pyrimidine

Yeast cells containing induced α-glucosidase activity lose 10% of the original activity per hour when placed in phosphate buffer – glucose medium. The presence of inducer has no effect on the rate of loss. Induced cells placed in complex medium plus glucose or glycerol show an initial rise in α-glucosidase activity, and then a slow decrease which is accelerated when growth stops. The loss of induced enzyme activity in buffer–glucose medium is inhibited by inhibitors of energy production or protein synthesis whether they are added immediately or 2 or 4 h after suspension of cells in the medium. The ability of the inhibitors to block the loss of induced enzyme activity is correlated with their ability to inhibit protein synthesis. Ammonium sulfate inhibits the loss of α-glucosidase activity after a lag but amino acid or purine–pyrimidine mixtures do not. The loss of induced enzyme activity in cell-free supernatant solutions is less than 2% of the original activity per hour at 30°.

Presence of α-glucosidases in the male reproductive system of the rat and hormonal influences

1983 ◽  
Vol 61 (7) ◽  
pp. 764-769 ◽  
Author(s):  
Anne-Marie Grandmont ◽  
Pierre Chapdelaine ◽  
Roland R. Tremblay
Keyword(s):  
Enzyme Activity ◽  
Reproductive System ◽  
Reproductive Organs ◽  
Gonadal Hormones ◽  
Antagonistic Effect ◽  
Seminal Vesicles ◽  
Male Reproductive System ◽  
Male Rat ◽  
Glucosidase Activity ◽  
Estradiol 17Β

The use of a synthetic substrate (p-nitrophenyl-α-D-glucoside) to measure α-glucosidase activity has allowed us to demonstrate the presence of acid and neutral α-glucosidases in the reproductive organs of the male rat. Both enzymes increased in the epididymis, particularly in the caput segment, along with initiation of spermatogenesis at puberty; it then started decreasing after 12 weeks of life. Similar variations were not recorded in testis, prostate, and seminal vesicles. Castration led to a significant decrease of acid and neutral α-glucosidases in all accessory reproductive organs, but administration of testosterone proprionate (50 μg/day for 10 days) restored the enzyme activity to its original level. When estradiol-17β (5 mg) was administered simultaneously with testosterone (500 μg), the antagonistic effect of estradiol on testosterone was particularly evident on the levels of neutral α-glucosidases which reached the castration range, while the acid α-glucosidase remained unchanged in epididymis, prostate, and seminal vesicles. These results show that both acid and neutral α-glucosidases may be influenced by gonadal hormones in the male rat.

scholarly journals Effects of castration, 5 -dihydrotestosterone and cyproterone acetate on enzyme activity in the mouse epididymis

Reproduction ◽  
1979 ◽  
Vol 57 (1) ◽  
pp. 73-77 ◽  
Author(s):  
R. K. Rastogi ◽  
M. Milone ◽  
M. Di Meglio ◽  
M. F. Caliendo ◽  
G. Chieffi
Keyword(s):  
Enzyme Activity ◽  
Cyproterone Acetate ◽  
Mouse Epididymis
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