1. Academic Validation
  2. Effects of various calcium transporters on mitochondrial Ca2+ changes and oocyte maturation

Effects of various calcium transporters on mitochondrial Ca2+ changes and oocyte maturation

  • J Cell Physiol. 2021 Sep;236(9):6548-6558. doi: 10.1002/jcp.30327.
Feng Wang 1 2 3 Li-Hua Fan 1 Ang Li 2 Feng Dong 2 Yi Hou 2 Heide Schatten 4 Qing-Yuan Sun 1 Xiang-Hong Ou 1
Affiliations

Affiliations

  • 1 Fertility Preservation Lab, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, China.
  • 2 State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
  • 3 Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), Guangzhou, China.
  • 4 Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA.
Abstract

Ca2+ participates in many important cellular processes, but the underlying mechanisms are still poorly understood, especially during oocyte maturation. First, we confirmed that calcium in the culture medium was essential for oocyte maturation. Next, various inhibitors of Ca2+ channels were applied to investigate their roles in mitochondrial Ca2+ changes and oocyte maturation. Our results showed that Trmp7, Orai, T-type Ca2+ channels and Na+ /Ca2+ exchanger complex (NCLX) were important for oocyte maturation. Trmp7 inhibition delayed germinal vesicle breakdown. Orai and NCLX inhibition significantly weakened the distribution of mitochondrial Ca2+ around the nucleus compared to the Ctrl group. Interestingly, even T-type Ca2+ channels-specific inhibitor Mibefradil blocked germinal vesicle breakdown; mitochondrial Ca2+ surrounding the nucleus still was maintained at a high level without spindle formation. Two calcium transporter inhibitors, Thapsigargin and Ruthenium Red, which have been confirmed to inhibit oocyte activation, did not significantly affect oocyte maturation. Increasing the knowledge of calcium transport may provide a basis to build on for improving oocyte in vitro maturation in human assisted reproduction clinics.

Keywords

Ca2+ transport; assisted reproductive technology (ART); oocyte maturation.

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