0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Human Health Effects Nanoplastics Sign in to save

Co-exposure to environmentally relevant concentrations of cadmium and polystyrene nanoplastics induced oxidative stress, ferroptosis and excessive mitophagy in mice kidney

Environmental Pollution 2023 80 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Wenyue Qiu, Jiali Ye, Y. Su, Xinting Zhang, Xiaoyue Pang, Jianzhao Liao, Rongmei Wang, Zhao Cuiyan, Hui Zhang, Hui Zhang, Lianmei Hu, Zhaoxin Tang, Rongsheng Su

Summary

A mouse study found that combined exposure to cadmium (a toxic metal) and polystyrene nanoplastics caused more kidney damage than either pollutant alone. The combination triggered a harmful chain reaction involving oxidative stress, iron buildup, and excessive breakdown of cellular energy factories called mitochondria. This is significant because people are often exposed to both nanoplastics and heavy metals simultaneously, and their combined effects may be worse than expected.

Polymers
Body Systems
Models

Nanoplastics (NPs) are defined as a group of emerging pollutants. However, the adverse effect of NPs and/or heavy metals on mammals is still largely unclear. Therefore, we performed a 35-day chronic toxicity experiment with mice to observe the impacts of exposure to Cadmium (Cd) and/or polystyrene nanoplastics (PSNPs). This study revealed that combined exposure to Cd and PSNPs added to the mice's growth toxicity and kidney damage. Moreover, Cd and PSNPs co-exposure obviously increased the MDA level and expressions of 4-HNE and 8-OHDG while decreasing the activity of antioxidase in kidneys via inhibiting the Nrf2 pathway and its downstream genes and proteins expression. More importantly, the results suggested for the first time that Cd and PSNPs co-exposure synergistically increased iron concentration in kidneys, and induced ferroptosis through regulating expression levels of SLC7A11, GPX4, PTGS2, HMGB1, FTH1 and FTL. Simultaneously, Cd and PSNPs co-exposure further increased the expression levels of Pink, Parkin, ATG5, Beclin1, and LC3 while significantly reducing the P62 expression level. In brief, this study found that combined exposure to Cd and PSNPs synergistically caused oxidative stress, ferroptosis and excessive mitophagy ultimately aggravating kidney damage in mice, which provided new insight into the combined toxic effect between heavy metals and PSNPs on mammals.

Share this paper