Effects of Perfluorooctanoic Acid on the Associated Genes Expression of Autophagy Signaling Pathway of Carassius auratus Lymphocytes in vitro

Abstract

Perfluorooctanoic acid (PFOA) has been detected in various water bodies and caused harm to aquatic organisms. The aim of this study was to investigate the cytotoxicity and mechanism associated with autophagy and oxidative stress after exposure to PFOA (0, 1, 10, 100 μg/L) for 12 h on lymphocytes, which was isolated from the head kidney of Carassius auratus (C. auratus). Both of autophagy formation, cell activity, and intracellular reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels were measured. The relative expression of partial autophagy-related genes autophagy related 5 (Atg 5), autophagy related 7 (Atg 7), and Beclin 1 were also cloned and detected. Homologous relationships analysis showed high identities of genes in C. auratus and other fish by blast. C. auratus lymphocytes growth inhibition rates was increased induced by PFOA. Compared with the control group, the ROS generation and the MDA content were significantly increased in all of the PFOA-treated group. Besides, decreased SOD activity and decrease of GSH activity induced by PFOA further confirmed the occurrence of oxidative stress. The number of autophagosome formations was increased in a dose-dependent manner. Compared with the control group, Atg 7 and Beclin 1 mRNA expression was elevated significantly after PFOA exposed, showing a time-dependent manner, while mRNA expression of Atg 5 was increased remarkably in 100 μg/L PFOA-treated group. Our results indicated that PFOA caused oxidative damage to lymphocytes in C. auratus and caused various autophagy signaling pathway-associated genes imbalances in the lymphocytes. Autophagy signaling pathway-associated genes imbalance could weaken antioxidant capacity and involve in the mechanism of C. auratus lymphocytes oxidative injury caused by PFOA.