Purpose

Microgravity has severe effects on cellular and molecular structures as well as on metabolic interactions. The aim of this study is to investigate the effects of microgravity (μg) exposure on human frozen sperm samples.

Methods

Sibling samples from 15 normozoospermic healthy donors were frozen using glycerol as cryoprotectant and analyzed under microgravity and ground conditions. Microgravity was obtained by parabolic flights using a CAP10B plane. The plane executed 20 parabolic maneuvers with a mean of 8.5 s of microgravity for each parabola.

Results

Frozen sperm samples preserved in cryostraws and stored in a secure and specific nitrogen vapor cryoshipper do not suffer significant alterations after μg exposure. Comparing the study group (μg) and the control group (1 g), similar results were obtained in the main parameters studied: sperm motility (M/ml) 13.72 ± 12.57 vs 13.03 ± 12.13 (− 0.69 95% CI [− 2.9; 1.52]), progressive a + b sperm motility (%) 21.83 ± 11.69 vs 22.54 ± 12.83 (0.03 95% CI [− 0.08; 0.15]), sperm vitality (%) 46.42 ± 10.81 vs 44.62 ± 9.34 (− 0.04 95% CI [− 0.13; 0.05]), morphologically normal spermatozoa (%) 7.03 ± 2.61 vs 8.09 ± 3.61 (0.12 95% CI [0.01; 0.24]), DNA sperm fragmentation by SCD (%) 13.33 ± 5.12 vs 13.88 ± 6.14 (0.03 95% CI [− 0.09; 0.16]), and apoptotic spermatozoa by MACS (%) 15.47 ± 15.04 vs 23.80 ± 23.63 (− 0.20 95% CI [− 0.66; 1.05]).

Conclusion

The lack of differences obtained between frozen samples exposed to μg and those maintained in ground conditions provides the possibility of considering the safe transport of human male gametes to space. Nevertheless, further research is needed to validate the results and to consider the possibility of creating a human sperm bank outside the Earth.

Trial registration number

ClinicalTrials.gov: NCT03760783

中文翻译：

---

微重力对冷冻人类精子样本的影响。

目的

微重力对细胞和分子结构以及代谢相互作用有严重影响。本研究的目的是研究微重力 (μg) 暴露对人类冷冻精子样本的影响。

方法

使用甘油作为冷冻保护剂冷冻来自 15 名正常精子健康供体的兄弟姐妹样本，并在微重力和地面条件下进行分析。微重力是通过使用 CAP10B 飞机的抛物线飞行获得的。飞机执行了 20 次抛物线机动，每条抛物线的微重力平均为 8.5 秒。

结果

保存在冷冻管中并储存在安全且特定的氮蒸气冷冻运送器中的冷冻精子样本在微克暴露后不会发生显着变化。比较研究组 (μg) 和对照组 (1 g)，研究的主要参数获得了相似的结果：精子活力 (M/ml) 13.72 ± 12.57 vs 13.03 ± 12.13 (- 0.69 95% CI [- 2.9; 1.52])，a + b 精子活力 (%) 21.83 ± 11.69 vs 22.54 ± 12.83 (0.03 95% CI [− 0.08; 0.15])，精子活力 (%) 46.42 ± 10.81 vs 490.34 (%) CI [− 0.13; 0.05])，形态正常的精子 (%) 7.03 ± 2.61 vs 8.09 ± 3.61 (0.12 95% CI [0.01; 0.24])，SCD 导致的 DNA 精子碎片 (%) 13.33 (%) ± 13.38 ± 5.812 0.03 95% CI [- 0.09; 0.16])，MACS 的凋亡精子 (%) 15.47 ± 15.04 vs 23.80 ± 23.63 (- 0.20 95% CI [- 0.66; 1.05])。

结论

暴露于 μg 的冷冻样品与保持在地面条件下的冷冻样品之间没有差异，这为考虑将人类雄配子安全运输到太空提供了可能性。尽管如此，还需要进一步的研究来验证结果并考虑在地球之外创建人类精子库的可能性。

试用注册号

ClinicalTrials.gov：NCT03760783