Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0265264 (HOS)
 1,119 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Semen cryopreservation processes generally decrease sperm quality and fertility rate, but this is highly dependent on the specific susceptibility of sperm cells to low temperatures. In order to study the effect of cooling, freezing, and thawing on ram spermatozoa, sperm viability (plasma membrane integrity), HOS test (hyposmotic swelling test), and individual motility were assessed in fresh, cooled, and frozen-thawed samples. The cryoprotective ability of four extenders [Triladyl-yolk (20% Triladyl, 20% egg yolk), Salamon (9.9% raffinose, 2% sodium citrate, 15% egg yolk, 5% glycerol), I.N. I.A. (6.31% Tes, 1.51% Tris, 6% egg yolk, 3% glycerol), and Fiser (F1: 3.25% Tris, 9.3% fructose, 1.7% citric acid, 25% egg yolk, 2% glycerol; F2: 0.68% sodium citrate, 0.15% TES, 0.36% glycine, 10.18% lactose, 1.18% raffinose, 0.5% fructose, 3.95% dextran (150,000-200, 000 MW); 12% of the obtained solution was replaced by the same volume of glycerol)] was tested, as well as the effect of adding various compounds (bovine lactalbumin and serum albumin, vitamin E, dithiothreitol, bull seminal plasma, glycine betaine, proline, phosphatidylcholine, and cholesterol) to Fiser's medium. Simultaneously, centrifugal counter-current distribution in an aqueous two-phase system was carried out to analyze the effect of the four extenders on sperm surface heterogeneity. The results showed that ram spermatozoa undergo a dramatic loss of heterogeneity, viability, motility, and positive response to the HOS test during freezing and thawing. These changes were partially prevented by diluting samples in Fiser's extender containing egg yolk and glycerol. A considerable increase in sperm quality with respect to that obtained in Fiser's control sample was achieved by the addition of bovine lactalbumin, vitamin E, bovine serum albumin, and bovine and ram seminal plasma.
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PMID:Improvement of ram sperm cryopreservation protocols assessed by sperm quality parameters and heterogeneity analysis. 969 24

The main goal of this study was to investigate the potential protective effects of enzymatic and nonenzymatic antioxidants on cryopreservation injuries to red deer epididymal spermatozoa. In Experiment 1, the effects on sperm freezability of the enzymatic antioxidants catalase, superoxide dismutase, and a combination thereof were studied. In Experiment 2, sperm cryoresistance was evaluated when different nonenzymatic antioxidants, such as vitamin E, vitamin C, and butylated hydroxytoluene (BHT), were added to the freezing extender. Sperm quality was judged in vitro by microscopic assessments of individual sperm motility (SMI), viability, and acrosome (ie, spermatozoa with normal apical ridges; % NAR) and membrane (by means of the HOS test) integrity. To address fully these topics, we incorporated a new set of functional sperm tests for mitochondrial function, membrane phospholipid disorder, and sperm chromatin stability. Samples were evaluated after freezing and thawing, and after a 2-hour period of incubation at 37 degrees C. The present study demonstrates that the addition of enzymatic antioxidants to freezing extenders improves sperm viability after cooling, and improves sperm motility, acrosome integrity, and mitochondrial status (P<.05) after thawing. After a 2-hour incubation period at 37 degrees C in the presence of enzymatic antioxidants, an improvement in membrane integrity (P<.05) was observed. However, when nonenzymatic antioxidants were present in the freezing diluents, no positive effects on thawed sperm parameters were noted. The chromatin stability test did not show significant differences between the treatments. We conclude that enzymatic antioxidants should be present in the early steps of cryopreservation of epididymal spermatozoa from red deer, so as to improve motility and acrosome integrity.
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PMID:Sperm characteristics and DNA integrity of Iberian red deer (Cervus elaphus hispanicus) epididymal spermatozoa frozen in the presence of enzymatic and nonenzymatic antioxidants. 1707 44