College of Veterinary Science, Assam Agricultural University, Guwahati, India.
Semen Biology Laboratory, Division of Animal and Fisheries Science, Indian Council of Agricultural Research (ICAR) Research Complex for North Eastern Hill Region, Ri-Bhoi, Meghalaya, India.
Biol Trace Elem Res. 2023 Oct;201(10):4726-4745. doi: 10.1007/s12011-022-03551-6. Epub 2023 Jan 4.
Different nanoparticles (NPs) are currently being investigated for their potential role as cryoprotectant during semen cryopreservation in several mammalian species. It may be possible to improve semen quality following cryopreservation by supplementation of NPs in the freezing extenders. The present study was carried out in semen collected from four (4) Assam Hill Goat bucks (10 ejaculates per buck) to investigate the effect of supplementing zinc oxide (ZnO) and selenium (Se) NPs in Tris-citric acid-fructose yolk (TCFY) extender on in vitro sperm quality and in vivo fertility rate after freeze-thawing. The size morphology and zeta potential of ZnO and Se NPs were evaluated prior to its incorporation in the freezing extender. Qualified semen samples (> 70% progressive motility) were divided into five (5) aliquots and then diluted in TCFY extender containing ZnO and Se NP supplementation at different concentrations (T, control; T, 0.1 mg/mL ZnO NPs; T, 0.5 mg/mL ZnO NPs; T, 0.5 µg/mL Se NPs; and T, 1 µg/mL Se NPs). Diluted semen was packed in 0.25 mL straws and then stored in liquid nitrogen. After thawing, post-thaw in vitro sperm attributes were evaluated. Finally, the effect of NPs on in vivo fertility rate was checked in heat-synched does (n = 70) by artificial insemination (AI) using straws that showed superior results during the in vitro study. Results showed that ZnO and Se NPs were poly-crystalline in nature with particle size below 100 nm (nm). The evaluated post-thaw sperm in vitro attributes were significantly (p < 0.001) higher in T in comparison to T. The antioxidant enzyme activities were significantly (p < 0.001) higher in T. Lipid peroxidation (LPO) profile was significantly (p < 0.001) lower in T. Sperm motility and mitochondrial membrane potential (MMP) had a highly significant (r = 0.580, p < 0.05) association in T. No significant (p > 0.05) differences in pregnancy rates were recorded after AI in the different treatments. In conclusion, extender supplemented with 0.1 mg/mL ZnO NPs improved post-thaw semen quality of goat spermatozoa consequently by increasing activities of endogenous antioxidant enzymes thereby lowering LPO levels. However, improved in vitro outcomes might not correspond to improved field fertility outcomes.
不同的纳米颗粒（NPs）目前正在被研究，以探索其在几种哺乳动物的精液冷冻保存中作为抗冻保护剂的潜力。通过在冷冻稀释液中添加 NPs，可能会改善冷冻保存后的精液质量。本研究在 4 只（4 只）阿萨姆邦山羊公山羊采集的精液中进行，以研究在 Tris-柠檬酸-果糖蛋黄（TCFY）稀释液中添加氧化锌（ZnO）和硒（Se）纳米颗粒对冷冻解冻后体外精子质量和体内受精率的影响。在将 ZnO 和 Se NPs 掺入冷冻稀释液之前，对其大小形态和zeta 电位进行了评估。合格的精液样本（>70%的前向运动精子）分为 5 份，并在含有 ZnO 和 Se NP 补充剂的 TCFY 稀释液中稀释不同浓度（T，对照；T，0.1mg/mL ZnO NPs；T，0.5mg/mL ZnO NPs；T，0.5μg/mL Se NPs；和 T，1μg/mL Se NPs）。稀释后的精液装入 0.25ml 细管中，然后储存在液氮中。解冻后，评估解冻后的体外精子参数。最后，通过人工授精（AI）检查纳米粒子对热同步母羊体内受精率的影响，使用在体外研究中表现优异的细管。结果表明，ZnO 和 Se NPs 为多晶态，粒径小于 100nm（nm）。与 T 相比，T 中评估的解冻后体外精子参数显著（p<0.001）更高。抗氧化酶活性显著（p<0.001）高于 T。脂质过氧化（LPO）谱在 T 中显著（p<0.001）降低。T 中精子运动和线粒体膜电位（MMP）具有高度显著的（r=0.580，p<0.05）相关性。不同处理后的妊娠率无显著差异（p>0.05）。总之，在冷冻稀释液中添加 0.1mg/mL ZnO NPs 可提高山羊精子解冻后的精液质量，从而提高内源性抗氧化酶的活性，降低 LPO 水平。然而，体外结果的改善可能与田间生育力结果的改善不一致。
