Molecular mechanisms of physiological change under acute total dissolved gas supersaturation stress in yellow catfish (Pelteobagrus fulvidraco)

• Published in: Environmental science and pollution research international 2023-09, Vol.30 (43), p.97911-97924
• Main Authors: Chen, Yeyu, Wu, Xiaoyun, Lai, Jiansheng, Yan, Boqin, Gong, Quan
• Format: Article
• Language: English
• Subjects: 1-Phosphatidylinositol 3-kinase; Aeration; AKT protein; Amino acids; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Catfish; Dissolved gases; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Fish diseases; Genes; Gills; Heat shock proteins; Metabolic pathways; Metabolites; Metabolomics; Molecular modelling; Pelteobagrus fulvidraco; Physiological effects; Physiology; Research Article; Signs and symptoms; Superoxide dismutase; Supersaturation; TOR protein; Transcriptomics; Triglycerides; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-29157-6

During the dam discharging period, the strong aeration of high-speed water leads to the supersaturation of total dissolved gas (TDG) in the downstream water, which causes gas bubble disease (GBD) in fish and threatens their survival. TDG supersaturation has now become an ecological and environmental issue of global concern; however, the molecular mechanism underlying the physiological effect of TDG supersaturation on fish is poorly known. Here, we comprehensively investigated the effect of TDG supersaturation on Pelteobagrus fulvidraco at the histopathological, biochemical, transcriptomic, and metabolomic levels. After exposure to 116% TDG, P. fulvidraco exhibited classic GBD symptoms and pathological changes in gills. The level of superoxide dismutase was highly significantly decreased. Transcriptomic results revealed that heat shock proteins (HSPs) and a large number of genes involved in immunity were increased by TDG stress. A key environmental sensor PI3K/Akt/mTOR pathway was significantly stimulated for defence against stress. Integrated transcriptomic and metabolomic analyses revealed that key metabolites and genes were upregulated in the triacylglycerol synthesis pathway and that amino acid levels decreased, which might be associated with TDG supersaturation stress. The present study demonstrated that TDG supersaturation could cause severe physiological damage in fish. HSP genes, immune functions, and energy metabolic pathways were enhanced to counteract the adverse effects.