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Updated: Jun 13, 2026
07:46
Detection of DNA Double-Stranded Breaks in Mouse Oocytes
Published on: June 23, 2023
Stage-dependent DNA damage and mitochondrial dysfunction under simulated microgravity constrain oocyte maturation and
Yuqing Gao1,2,3,4, Lei Ge2,3,4, Tianxia Xiao2,3,4
1Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Macau, 999078, China.
Cell Communication and Signaling : CCS
|June 12, 2026
Summary
Simulated microgravity damages oocytes during meiotic arrest, but melatonin (MLT) protects them by aiding DNA repair and improving mitochondrial function, offering a potential spaceflight countermeasure.
Area of Science:
- Reproductive biology
- Space medicine
- Molecular biology
Background:
- Spaceflight poses risks to female reproductive health, particularly affecting oocytes.
- Oocytes are vulnerable to DNA damage during meiotic arrest under microgravity stress.
Purpose of the Study:
- To investigate if simulated microgravity (SMG) causes genomic damage in oocytes.
- To determine if melatonin (MLT) can mitigate SMG-induced damage and improve oocyte quality.
Main Methods:
- Utilized simulated microgravity (SMG) as a stress model for mammalian oocytes.
- Assessed DNA damage, apoptosis, mitochondrial function, and meiotic maturation.
- Investigated the role of melatonin (MLT) and its receptors in mitigating SMG effects.
Main Results:
- SMG induced DNA double-strand breaks and apoptosis in prophase-arrested oocytes.
- Melatonin (MLT) alleviated DNA damage via DNA-PKcs/NHEJ, improved mitochondrial distribution, and reduced apoptosis.
- MLT enhanced meiotic maturation, spindle integrity, and developmental competence, largely independent of MT1/MT2 receptors.
Conclusions:
- SMG directly damages oocytes, impacting DNA integrity and mitochondrial homeostasis.
- Melatonin (MLT) is a promising therapeutic agent for protecting oocyte quality during spaceflight.
- MLT's protective mechanisms involve DNA repair and mitochondrial regulation, offering a potential countermeasure for astronauts.
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