Combined Effects of Elevated Temperature and Polystyrene Microplastics on Hemocyte Function, Immune-Related Gene Expression, and Energy Metabolism of Crassostrea gigas

• Main Authors: Yunchao DU, Jingying REN, Jia TENG, Jianmin ZHAO, Tianyu ZHANG, Qing WANG
• Format: Article in Journal/Newspaper
• Language: English; Chinese
• Published: Science Press, PR China 2024
• Subjects: crassostrea gigas; microplastics; elevated temperature; immune; energy metabolism; Aquaculture. Fisheries. Angling; SH1-691; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: https://doi.org/10.19663/j.issn2095-9869.20230217001; https://doaj.org/article/85bcd656c911491dadac59fd94fc295f

Bivalves are affected by various stressors, such as global warming and microplastics, in the marine environment. Microplastics are one of the most concerning pollutants worldwide, and high seawater temperatures caused by global warming influence the survival of marine organisms. However, little is known about the combined effects of elevated temperature and microplastics (MPs) on marine organisms, and most studies conducted in recent years have investigated the two factors, respectively. Thus, it is necessary to investigate the combined effects of elevated temperature and MP exposure on marine life. The Pacific oyster Crassostrea gigas is a widely distributed marine mollusk, and has very important economic value. The aim of the current study was to explore the toxic effects of elevated temperature and microplastic co-exposure on the hemocyte function, immune-related gene expression, and energy metabolism of C. gigas. In the current study, oysters were exposed to three levels of microplastics (no microplastics, 6 μm microplastics: SPS-MPs, and 50~60 μm microplastics: LPS-MPs) and two temperature levels (20 ℃ and 25 ℃) for 21 days, and the phagocytosis rate and reactive oxygen species (ROS) content of hemocytes, glycogen content in digestive glands, and immune-related gene expression in digestive glands and gills were examined on the 21st day. 2', 7'-Dichlorodihydrofluorescein diacetate and fluorescent microspheres were used to measure the ROS content and phagocytosis ratein hemocytes of C. gigas by flow cytometry, respectively. The glycogen content was measured using detection kits. Total RNA was isolated by TRIzol reagent, and the concentration was measured by Nanodrop. M-MLV Reverse Transcriptase was used for cDNA synthesis. The expressions of immune-related genes [inhibitor of NF-κB (IκB), p53, and heat shock protein 90 (HSP90)] were examined by quantitative real-time PCR in the digestive glands and gills of oysters from each treatment group. Two-way ANOVA was used to analyze the interactive effects of ...