Antioxidant-supplemented media modulates ROS by regulating complex I during mouse oocyte maturation

Area of Science:

• Reproductive Biology
• Mitochondrial Biology
• Cellular Physiology

Background:

• In Vitro Oocyte Maturation (IVM) is crucial for assisted reproduction but can cause oxidative stress.
• Reactive Oxygen Species (ROS) imbalance during IVM can harm oocyte quality.
• The effect of antioxidants on Complex I, a key ROS-producing mitochondrial protein, during IVM is not well understood.

Purpose of the Study:

• To investigate Complex I expression during mouse oogenesis.
• To determine the impact of specific antioxidants on Complex I and ROS levels during IVM.
• To provide insights into optimizing IVM protocols for improved female fertility.

Main Methods:

• Mouse oocytes at the germinal vesicle (GV) stage were cultured in media supplemented with acetyl-l-carnitine (ALC), α-lipoic acid (ALA), MitoQ, or N-acetyl-l-cysteine (NAC).
• Oocytes were analyzed at metaphase I (MI) and metaphase II (MII) stages.
• Levels of Complex I and ROS were quantified in treated oocytes.

Main Results:

• Complex I and ROS levels naturally increased from GV to MI and MII stages.
• ALA and NAC significantly elevated Complex I and ROS levels in MI and MII oocytes.
• MitoQ markedly reduced Complex I and ROS levels in MI and MII oocytes.
• ALC showed no effect on MI oocytes but decreased Complex I and ROS in MII oocytes.

Conclusions:

• Different antioxidants exert distinct effects on Complex I and ROS during oocyte maturation.
• Understanding these interactions is vital for mitigating oxidative stress in IVM.
• This research may lead to improved IVM techniques and enhanced female fertility outcomes.