Immunocytochemical Localization of β-N-Acetyl Glucosaminidase in Human Reproductive Organs1

Kapur, Deepak K.; Gupta, G. S.

doi:10.1095/biolreprod38.2.373

Cited by 13 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Reproductive impairment also has been documented in mouse models of Tay-Sachs and Sandhoff diseases, [12][13][14] related sphingolipid storage disorders that result from deficient ␤-hexosaminidase activity and the accumulation of GM 2 ganglioside. Of particular relevance to the current study, the reproductive pathology and residual enzyme expression in male Tay-Sachs and Sandhoff mice has been characterized, and an increase in the size and number of lysosomes in the epithelia lining the efferent and epididymal ducts was found.…”

mentioning

confidence: 99%

Reproductive Pathology and Sperm Physiology in Acid Sphingomyelinase-Deficient Mice

Butler

Gordon

et al. 2002

The American Journal of Pathology

View full text Add to dashboard Cite

Types A and B Niemann-Pick disease (NPD) are lysosomal storage disorders resulting from the deficient activity of acid sphingomyelinase (ASM). In this manuscript we report the pathobiology of male gonadal tissue and sperm in a knockout mouse model of NPD and demonstrate the importance of ASM for normal sperm maturation and function. Characteristic lipid-filled vacuoles were evident in light micrographs of testis' seminiferous tubules and epithelial cells lining the epididymis of ؊/؊ mice. Electron micrographs extended these findings and revealed storage vesicles within Sertoli cells of the seminiferous tubules. Mature spermatozoa from ؊/؊ mice showed marked ASM deficiency and elevated levels of sphingomyelin and cholesterol. Flow cytometric analysis revealed that affected spermatozoa had disrupted plasma and acrosome membranes, and mitochondrial membrane depolarization. They also did not undergo proper capacitation. Morphological abnormalities such as kinks and bends at the midpieceprinciple piece junction were evident in spermatozoa from affected mice, with consequent deficits in motility. Notably, the mutant sperm regained normal morphology on incubation in mild detergent, demonstrating that the bending defects were a direct consequence of membrane lipid accumulation. A mechanism for these abnormalities is proposed that suggests lipid accumulation in the gonads results in regulatory volume decrease defects within the developing sperm, and that regulatory volume decrease defects, in turn, lead to the observed abnormalities in sperm morphology and function. These results provide in vivo evidence that ASM activity plays a critical role in sperm maturation and function, and a basis for similar studies in sexually mature, male NPD patients. 1 Type A NPD is a severe, neurodegenerative form of the disorder that generally leads to death by ϳ3 years of age. In contrast, patients with type B NPD have little or no neurological involvement and may survive into adolescence or adulthood. ASM belongs to a family of sphingomyelinases that catabolize sphingomyelin (SPM) to ceramide and phosphorylcholine. 2,3 It is presumed that the pathophysiology in NPD is primarily because of the accumulation of SPM and other metabolically related lipids (eg, cholesterol) within the cells and tissues of affected patients, although signaling through the ceramide pathway may also be disrupted.

show abstract

mentioning

confidence: 99%

Reproductive Pathology and Sperm Physiology in Acid Sphingomyelinase-Deficient Mice

Butler

Gordon

et al. 2002

The American Journal of Pathology

View full text Add to dashboard Cite

show abstract

“…Introduction b-N-acetylglucosaminidase (b-NAGase) is a common enzyme in animal tissues and body fluids (Nagdas et al, 2009). It has been described from cells of the rat spleen (Dong and Hart, 1994), in human testes and epididymis (Kapur and Gupta, 1988) and in human sperm (Miranda et al, 2000) as well as in those of rat (Chapman and Kilian, 1984), hamster (Zitta et al, 2006), chicken (Droba and Droba, 1992) and fruit fly (Cattaneo et al, 1997). The enzyme participates actively in the fertilisation process in mares (Brandon et al, 1997).…”

mentioning

confidence: 99%

Isolation and characteristics ofβ-N-acetylglucosaminidase present in rainbow trout (Oncorhynchus mykiss) and Siberian sturgeon (Acipenser baerii) milt

2012

View full text Add to dashboard Cite

Summary The aim of this study was to isolate and characterise the enzyme ß‐N‐acetylglucosaminidase (β‐NAGase) in rainbow trout and Siberian sturgeon milt, in order to find similarities or differences in its involvement in the fertilization process of these two species. While sturgeon sperm possess an acrosome, teleosts do not. Applying ion exchanging chromatography to β‐NAGase of rainbow trout sperm, two peaks of β‐NAGase activity were obtained from the plasma material and from the sperm. The molecular weight was 74 kDa for both milt plasma forms and 127 kDa for rainbow trout spermatozoa peak. Optimum pH of purified rainbow trout enzyme peaks ranged from 4.6 to 5.0. Michaelis–Menten constants were 11.59 × 10−4 and 11.48 × 10−4 m for I and II milt plasma peaks. Incubation of purified peaks I and II at 56°C resulted in a 45 to 50% decrease in activity of both forms. Km value for rainbow trout spermatozoa β‐NAGase was 5.4 × 10−4 m. Enzyme incubation tests at high temperature proved this form of the enzyme to be most resistant to high temperatures, since its activity after 20 min of incubation at 56°C decreased only by 25%. The molecular weight of the enzyme originating from Siberian sturgeon milt plasma was about 265 and 113 kDa for I and II milt plasma peaks, respectively, and 271 kDa for the sperm extract. Optimum pH for all sturgeon purified peaks ranged from 3.8 to 5.0. The Km constant was 5.12 × 10−4, 5.28 × 10−4 and 5.0 × 10−4 m for I and II milt plasma and spermatozoa peaks, respectively. The loss of ß‐NAGase activity at 56°C was 58% for both milt plasma peaks and 35% for the sturgeon spermatozoa peak. The kinetic parameters, especially thermostability of ß‐NAGase was similar to the homologous enzymes observed in mammalian semen.

show abstract

“…10 -12 Since constructing the ASM-deficient mouse model in 1995, our laboratory has observed reduced fecundity in the affected animals. Interestingly, reproductive impairment also has been documented in mouse models of Tay-Sachs and Sandhoff diseases, [13][14][15] two related sphingolipid storage disorders that result from deficient ␤-hexosaminidase activity and the accumulation of GM 2 ganglioside. Of particular relevance to the current study, the reproductive pathology and residual enzyme expression in male Tay-Sachs and Sandhoff mice has been characterized, and an increase in the size and number of lysosomes in the epithelia lining the efferent and epididymal ducts was found.…”

mentioning

confidence: 99%

Sperm Abnormalities in Heterozygous Acid Sphingomyelinase Knockout Mice Reveal a Novel Approach for the Prevention of Genetic Diseases

Butler

Gordon

Gátt

et al. 2007

The American Journal of Pathology

View full text Add to dashboard Cite

Acid sphingomyelinase knockout mice are a model of the inherited human disorder types A and B NiemannPick disease. Herein, we show that heterozygous (ASMKO ؉/؊ ) mice have two distinct sperm populations resembling those found in normal and mutant animals, respectively, and that these two populations could be distinguished by their morphology, ability to undergo capacitation or the acrosome reaction, and/or mitochondrial membrane potential (MMP). The abnormal morphology of the mutant sperm could be normalized by demembranation with detergents or by the addition of recombinant acid sphingomyelinase to the culture media, and the corrected sperm also had an enhanced fertilization capacity. Methods were then explored to enrich for normal sperm from the mixed ASMKO ؉/؊ population, and flow cytometric sorting based on MMP provided the best results. In vitro fertilization was performed using ASMKO ؉/؊ oocytes and sperm before and after MMP sorting, and it was found that the sorted sperm produced significantly more wild-type pups than nonsorted sperm. Sperm sorting is much less invasive and more cost-effective than egg isolation, and offers several advantages over the existing assisted reproduction options for Niemann-Pick disease carrier couples. It therefore could have a major impact on the prevention of this and perhaps other genetic diseases. (Am J

show abstract

Immunocytochemical Localization of β-N-Acetyl Glucosaminidase in Human Reproductive Organs1

Cited by 13 publications

References 0 publications

Reproductive Pathology and Sperm Physiology in Acid Sphingomyelinase-Deficient Mice

Reproductive Pathology and Sperm Physiology in Acid Sphingomyelinase-Deficient Mice

Isolation and characteristics ofβ-N-acetylglucosaminidase present in rainbow trout (Oncorhynchus mykiss) and Siberian sturgeon (Acipenser baerii) milt

Sperm Abnormalities in Heterozygous Acid Sphingomyelinase Knockout Mice Reveal a Novel Approach for the Prevention of Genetic Diseases

Contact Info

Product

Resources

About