Ustiloxin A impairs oocyte quality by disrupting organelles function.

Area of Science:

• Reproductive Biology
• Toxicology
• Cell Biology

Background:

• Oocyte quality is crucial for successful fertilization and embryonic development.
• Ustiloxin A (UA), a mycotoxin found in rice, is known for its phytotoxic and cytotoxic effects.
• The impact of UA on oocyte maturation has not been previously investigated.

Purpose of the Study:

• To investigate the effects of acute Ustiloxin A (UA) exposure on mouse oocyte maturation.
• To elucidate the mechanisms by which UA affects oocyte meiotic progression and cellular integrity.

Main Methods:

• Exposure of mouse oocytes to varying concentrations of Ustiloxin A (UA).
• Assessment of meiotic maturation, spindle assembly, actin density, and mitochondrial function.
• Analysis of gene expression related to mitochondrial dynamics, oxidative stress, DNA damage, ER stress, and apoptosis.

Main Results:

• UA exposure inhibited oocyte maturation in a dose-dependent manner, causing meiotic arrest.
• Disruption of spindle assembly, reduced actin density, and impaired mitochondrial function (including membrane potential and TOM20 expression) were observed.
• UA induced oxidative stress, DNA damage, ER and Golgi dysfunction, ER stress (increased GRP78), autophagy, and early apoptosis in oocytes.

Conclusions:

• Ustiloxin A (UA) significantly impairs mouse oocyte quality by disrupting key cellular organelles and functions.
• UA exposure leads to meiotic arrest, mitochondrial dysfunction, oxidative stress, and apoptosis, negatively impacting female reproductive potential.
• These findings highlight the potential reproductive risks associated with Ustiloxin A (UA) contamination.