Maternal exposure to urban particulate matter induces cardiac developmental toxicity in zebrafish offspring by disrupting mitochondrial homeostasis

Abstract

Introduction

Urban particulate matter (UPM) is a major air pollutant affecting public health, with maternal exposure potentially leading to cardiac developmental disorders in offspring. However, the exact mechanisms underlying the intergenerational effects of UPM remain unclear.

Objective

This study aimed to investigate the molecular mechanisms involved in cardiac developmental defects caused by maternal UPM exposure in offspring zebrafish.

Methods and results

Female zebrafish were exposed to UPM for 21 days to examine intergenerational effects. The results indicated that maternal zebrafish in the exposed group exhibited ovarian damage and a reduced number of embryos and fertilization rates. Zebrafish offspring exhibited abnormal cardiac development, including pericardial edema and pathological heart injury. Mechanistically, transcriptomic analysis of the offspring indicated that UPM exposure induced significant modifications in the mitochondrial biogenesis pathway, with altered expression of mitochondrial function-related genes. Maternal UPM exposure impaired respiration in zebrafish embryos and increased angiopoietin-like 4 (ANGPTL4) expression in offspring hearts. In vitro, Angptl4 knockdown alleviated UPM-induced mitochondrial membrane potential reduction and mitochondrial reactive oxygen species overproduction in cardiomyocytes, whereas Angptl4 overexpression exacerbated UPM-induced mitochondrial toxicity.

Conclusion

These findings show that maternal UPM exposure disrupts mitochondrial homeostasis by upregulating ANGPTL4 expression, leading to abnormal cardiac development in zebrafish offspring.