Department of Anatomical Sciences, School of Medicine, Tehran University of Medical Science, Building number 2, 16 Azar Street, Keshavarz Street, Tehran, 14155-6447, Iran.
Department of Medicine, School of Medicine, Tehran University of Medical Science, Tehran, Iran.
Cell Tissue Res. 2018 Apr;372(1):149-159. doi: 10.1007/s00441-017-2743-4. Epub 2017 Dec 1.
Cryopreservation is known to induce oxidative stress in spermatozoa. Although melatonin has powerful antioxidant properties, little is known about its effects on human sperm quality during cryopreservation. The present study was undertaken to investigate the effects of melatonin treatment on human sperm parameters essential for fertilization. We first evaluated the effects of various concentrations of melatonin (0-15 mM) on human sperm parameters such as motility, viability and levels of intracellular reactive oxygen species during cryopreservation in order to identify an optimal dose with the greatest effects for further studies. Liquefied semen samples were then divided into three aliquots: cryopreserved without melatonin (control), cryopreserved with 3 mM melatonin and fresh groups. After being thawed, samples were evaluated for motility, viability, membrane integrity, intracellular reactive oxygen species levels, caspase-3 activity and AKT phosphorylation. Treatment of spermatozoa with the various concentrations of melatonin significantly increased their motility and viability and decreased their intracellular reactive oxygen species levels compared with the control group. The optimal melatonin concentration (3 mM) significantly decreased the intracellular reactive oxygen species levels, caspase-3 activity and the percentage of both dead and apoptotic-like sperm cells and increased the vitality, progressive motility and total motility and AKT phosphorylation compared with the control group. Thus, melatonin exerts protective effects against cryodamage during human spermatozoa cryopreservation and may exert its effects via the PI3K/AKT signaling pathway.
冷冻保存已知会诱导精子发生氧化应激。尽管褪黑素具有强大的抗氧化特性，但关于其在冷冻保存过程中对人类精子质量的影响知之甚少。本研究旨在探讨褪黑素处理对人类精子受精所必需的参数的影响。我们首先评估了不同浓度的褪黑素（0-15mM）对冷冻保存过程中人类精子参数（如活力、活力和细胞内活性氧水平）的影响，以确定最佳剂量以获得最大效果进行进一步研究。然后将液化的精液样本分成三份：未经褪黑素冷冻保存（对照）、用 3mM 褪黑素冷冻保存和新鲜组。解冻后，对运动性、活力、膜完整性、细胞内活性氧水平、caspase-3 活性和 AKT 磷酸化进行评估。与对照组相比，用不同浓度的褪黑素处理精子可显著提高其活力和活力，并降低其细胞内活性氧水平。最佳褪黑素浓度（3mM）与对照组相比，显著降低细胞内活性氧水平、caspase-3 活性和死亡和凋亡样精子细胞的百分比，并增加活力、前向运动和总运动以及 AKT 磷酸化。因此，褪黑素在人类精子冷冻保存过程中对冷冻损伤具有保护作用，其作用可能通过 PI3K/AKT 信号通路发挥。
