Toxic Effect of Combined Exposure of Microplastics and Copper on Goldfish (Carassius auratus): Insight fromOxidative Stress, Inflammation, Apoptosis and Autophagy in Hepatopancreas and Intestine.

Abstract

The enhancement of the toxic effect of microplastics (MPs) on heavy metals and its mechanism needs more in-depth and systematic research. In this study, the copper (Cu) accumulation, histological injury, and expression of genes involved in oxidative stress, inflammation, apoptosis, and autophagy of goldfish after single or combined exposure of MPs (1mg/L) and Cu2+ (0.1mg/L) for 7days were determined. The results demonstrated that MPs enhanced the Cu accumulation in hepatopancreas and intestine of goldfishand induced more severe oxidative stress in the hepatopancreas and intestine of goldfish. Additionally, combined exposure of MPs and Cu induced inflammation, excessive apoptosis and insufficient autophagyin the hepatopancreas. Contrary, the inflammation and apoptosis were depressed in the intestine after combined exposure of MPs and Cu, which still requires further exploration.Hence, these findings provide further evidence for the threat of MPs and its adsorbed heavy metals.