Antioxidant Effect of Xanthan Gum on Ram Sperm after Freezing and Thawing.
Cryo Letters. 2017 May/Jun;38(3):187-193
Authors: Gastal GD, Silva EF, Mion B, Varela Junior AS, Rosa CE, Corcini CD, Mondadori RG, Vieira AD, Bianchi I, Lucia T
BACKGROUND: Xanthan gum is used as thickener in media to preserve food products, having cryoprotectant and antioxidant properties that may be relevant for sperm cryopreservation.
OBJECTIVE: To evaluate the effects of adding xanthan gum to freezing extenders on post-thawing quality and oxidant activity of ram sperm.
METHODS: Ejaculates from seven rams extended TRIS-egg yolk-glycerol were split in three treatments including xanthan gum (0.15%; 0.20%; and 0.25%) and a control with no xanthan gum.
RESULTS: After thawing, motility and production of reactive oxygen species (ROS) with 0.20% and 0.25% xanthan gum were lower than for the control (P < 0.05), but mitochondrial functionality and integrity of membrane, acrosome and DNA did not differ (P > 0.05). Xanthan gum at 0.20% and 0.25% may be an efficient antioxidant for frozen-thawed ram sperm, due to the reduction in ROS production.
PMID: 28767741 [PubMed – indexed for MEDLINE]
Tea polyphenol-T. arjuna bark as sperm antioxidant extender in infertile smokers.
Cryo Letters. 2017 Mar/Apr;38(2):95-99
Authors: Parameswari R, Rao KA, Manigandan P, Vickram AS, Archana A, Sridharan TB
BACKGROUND: Antioxidants protect spermatozoa against lipid peroxidation during freezing.
OBJECTIVE: The study is designed to elucidate the suitable extender to preserve infertile semen of smokers against ROS damage using natural Tea polyphenol (T. arjuna bark extract).
MATERIALS AND METHODS: Forty-two infertile subjects with smoking habit and 28 fertile subjects without smoking habit were considered for the study. Four semen extenders including our naturally derived antioxidant component were prepared and used to preserve semen sample from the study subjects for a period of one month. Standard semen parameters, biochemical and sperm DNA damage marker with inhibition were measured before and after cryopreservation.
RESULTS: The motility and morphology of sperm cells were maintained better in E4 extender, and DNA damage is reduced.
CONCLUSION: Extender recipe with natural antioxidants (E3 and E4) was found to be apt for infertile semen preservation.
PMID: 28534052 [PubMed – in process]
Effect of Monosaccharides in Glycerol-free Tris Extender on Reactive Oxygen Species and Apoptosis in Dog Sperm Cryopreservation.
Cryo Letters. 2017 Jan/Feb;38(1):51-57
Authors: Rahman MA, Park SH, Yu IJ
BACKGROUND OBJECTIVE: The present study investigated the effect of monosaccharides in a glycerol-free tris (GFT) extender on reactive oxygen species (ROS) levels and apoptosis in cryopreserved dog spermatozoa.
MATERIALS AND METHODS: The sperm pellets were resuspended (5 × 10(7) mL(-1)) with GFT containing 172 mM glucose (G), 86 mM glucose + 86 mM fructose (GF), 86 mM glucose + 86 mM galactose (Gg), 172 mM fructose (F), 172 mM galactose (g) or 86 mM fructose + 86 mM galactose (Fg). The sperm (500 µL) were loaded in 0.5 mL straws and cooled for 50 min at 4 degree C. The straws were then frozen 7 cm from the surface of liquid nitrogen (LN2) for 20 min and were finally plunged into LN2. After freezing-thawing, the sperm motility and viability were evaluated. The ROS level (H2O2) and apoptosis index were assessed by using flow cytometry.
RESULTS: GFT supplemented with GF resulted in significantly higher (P < 0.05) progressive sperm motility and viability followed by only G, which had greater ROS reducing capacity. However, sperm cell apoptosis had no significant differences among all the experimental groups.
CONCLUSION: Cryopreservation of dog sperm in GFT containing GF yields more motile and viable sperm followed by only G, which has greater ROS reducing efficiency.
PMID: 28376140 [PubMed – in process]
Effects of Tempol and Quercetin on Human Sperm Function after Cryopreservation.
Cryo Letters. 2017 Jan/Feb;38(1):29-36
Authors: Azadi L, Tavalaee M, Deemeh MR, Arbabian M, Nasr-Esfahani MH
BACKGROUND: Quercetin is a flavonoid with high reactive oxygen species (ROS) scavenging and ion chelating activity. It also enhances the activity of antioxidant enzymes and reduces enzymatic activity such as NADPH oxidase and NADH-dependent oxido-reductase. Tempol, as a superoxide dismutase mimetic agent, converts superoxide to less toxic hydrogen peroxide (H2O2), but cannot reduce highly toxic hydroxyl radicals in Fenton or Haber-Weiss reactions mediated with free iron or cupper.
OBJECTIVE: The study was to compare the effect of Quercetin and Tempol in an optimized commercial cryo-protective media on ROS induced cryoinjury for the first time.
MATERIALS AND METHODS: Following administration of these compounds during freezing process, sperm motility, viability, ROS production and DNA integrity were assessed before and after freezing/thawing process.
RESULTS: Data showed that 10 µM Quercetin and 5 µM Tempol significantly improved sperm motility and viability, but they together had no additive effect. Supplementation with Quercetin alone or combination of Quercetin with Tempol decrease the ROS concentration, but the reduction was not significant for Tempol alone compared to control group. Quercetin and Tempol significantly decrease DNA fragmentation.
CONCLUSION: The supplementation of Quercetin or Tempol, but not their combination improves the quality of cryopreserved human semen.
PMID: 28376137 [PubMed – in process]
Effect of melatonin supplementation on cryopreserved sperm quality in mouse.
Cryo Letters. 2016 Mar-Apr;37(2):115-22
Authors: Chen XJ, Zhang Y, Jia GX, Meng QG, Bunch TD, Liu GS, Zhu SE, Xhou GB
BACKGROUND: Antioxidants protect spermatozoa against cell damage during cryopreservation.
OBJECTIVE: To investigate whether melatonin supplement in the extender may improve the quality of cryopreserved mouse sperm.
METHODS: Kunming mice sperm frozen in extender R18S3 (18% (w/v) rafﬁnose and 3% (w/v) skim milk) supplemented with melatonin were thawed and evaluated.
RESULTS: Mouse spermatozoa were cryopreserved in the freezing extender R18S3 that contained melatonin at 0, 0.125, 0.25 and 0.5 mg/mL melatonin. The extender without melatonin supplement was associated with increased formation of reactive oxygen species (ROS) and decreased sperm motility. Melatonin supplement at 0.125 mg/mL significantly increased the progressive motility of sperm in comparison to other melatonin concentration or control. The percentage of thawed viable sperm with ROS was lower in the melatonin-treated groups than in untreated group. Melatonin supplement also increased antiapoptotic gene Bcl-xl expression in the thawed sperm.
CONCLUSION: Supplement of 0.125 mg/mL melatonin could reduce oxidative damage and apoptosis.
PMID: 27224523 [PubMed – in process]