Unit of Genetics, Department of Biology, Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain; Halotech DNA, Cantoblanco, Madrid 28049, Spain.
Halotech DNA, Cantoblanco, Madrid 28049, Spain.
Reprod Biomed Online. 2021 Dec;43(6):1079-1086. doi: 10.1016/j.rbmo.2021.09.015. Epub 2021 Sep 26.
What is the mechanism by which human follicular fluid inhibits seminal plasma DNase activity?
Human genomic DNA was incubated with human follicular fluid and seminal plasma (reaction mixture) under different experimental conditions; increasing volumes of human follicular fluid; proteinase K digested or heat inactivated human follicular fluid; and the addition of Ca or Mg to the reaction mixture.
Increasing volume of human follicular fluid resulted in a dose-dependent inhibition of seminal plasma DNase activity. Inhibition was not caused by proteins in the human follicular fluid as digestion with proteinase K or heat inactivation of human follicular fluid failed to abolish its inhibitory effect. Addition of divalent cations resulted in a reversion of the inhibitory effect, providing evidence that human follicular fluid inhibition of seminal plasma DNase activity seems to be mediated by a compound with chelating activity. Furthermore, incubation of genomic DNA with human follicular fluid in the presence of divalent cations served to elicit the existence of DNase activity.
Human follicular fluid seems to contain a molecule or molecules with chelating capacity that inhibits DNase activity of both follicular fluid and seminal plasma. Our findings provide new insight to understanding sperm preservation and the physiology of fertilization biology.
人卵泡液抑制精浆 DNA 酶活性的机制是什么？
将人基因组 DNA 与人卵泡液和精浆（反应混合物）在不同的实验条件下孵育；增加人卵泡液的体积；用蛋白酶 K 消化或热失活人卵泡液；向反应混合物中添加 Ca 或 Mg。
人卵泡液体积的增加导致精浆 DNA 酶活性呈剂量依赖性抑制。抑制不是由人卵泡液中的蛋白质引起的，因为用蛋白酶 K 消化或热失活人卵泡液都不能消除其抑制作用。添加二价阳离子导致抑制作用逆转，这表明人卵泡液抑制精浆 DNA 酶活性似乎是由具有螯合活性的化合物介导的。此外，在存在二价阳离子的情况下，将基因组 DNA 与人卵泡液孵育，这证明了存在 DNA 酶活性。
人卵泡液似乎含有一种或多种具有螯合能力的分子，能抑制卵泡液和精浆中的 DNA 酶活性。我们的发现为理解精子保存和受精生物学的生理学提供了新的见解。
