Reproductive toxicity of acute Cd exposure in mouse: Resulting in oocyte defects and decreased female fertility.
Cadmium (Cd), a known metal contaminant, is widespreadly used in industry, thereby human health is severely affected through the way of occupational and environmental exposure. The adverse effects of the exposure to Cd on the female reproductive system, especially oocyte maturation and fertility have not been clearly defined. In this study, we found the arrested development of ovaries and uteri after Cd exposure and determined oocyte quality via assessing the key regulators during meiotic maturation and fertilization. We found that Cd exposure impeded the mouse oocyte meiotic progression by disrupting the normal spindle assembly, chromosome alignment and actin cap formation. Besides, exposure to Cd induced oxidative stress with the increased reactive oxygen species and apoptosis levels, leading to abnormal mitochondrial distribution, insufficient energy supply, and DNA damage, which ultimately led to oocyte quality deterioration. We also analyzed the effects of cadmium on epigenetic modifications, and the levels of 5mC, H3K9me3 and H3K9ac decreased after acute exposure to cadmium. Further experiments showed that the litter size in Cd-exposed female mice reduced, thereby indicating increased reproductive Cd toxicity. In conclusion, Cd exposure impairs oocyte maturation and fertilization ability induced by oxidative stress, early apoptosis and epigenetic modifications, which lead to the decrease of female fertility.
['Cheng|Yuyao|Y|', 'Zhang|Jun|J|', 'Wu|Teng|T|', 'Jiang|Xianlei|X|', 'Jia|Huiqun|H|', 'Qing|Suzhu|S|', 'An|Quanli|Q|', 'Zhang|Yong|Y|', 'Su|Jianmin|J|']
D000255:Adenosine Triphosphate D000818:Animals D017209:Apoptosis D002104:Cadmium D044127:Epigenesis, Genetic D005260:Female D005298:Fertility D005455:Fluorescent Antibody Technique D005978:Glutathione D008540:Meiosis D051379:Mice D008815:Mice, Inbred Strains D008928:Mitochondria D009865:Oocytes D018384:Oxidative Stress D017382:Reactive Oxygen Species D014599:Uterus
Oocyte quality Oxidation stress Epigenetic modification Heavy metal pollution