基于多组学揭示臭氧胁迫对草鱼鳃抗氧化能力和能量代谢的影响OA

To investigate the effects of ozone exposure on physiological functions and the underlying molecular mechanisms in the gills of grass carp(Ctenopharyngodon idella),the fish were randomly divided into four groups and exposed to ozone concentrations of 0(control),0.1,0.2,and 0.3 mg/L for 24 h.Following exposure,antioxidant parameters and ion contents in gill tissues were measured,and metabolomic and transcriptomic analyses were performed.The results showed that ozone exposure significantly decreased superoxide dismutase(SOD)activity and the contents of malondialdehyde(MDA)and 8-hydroxydeoxyguanosine(8-OHdG),while increasing total antioxidant capacity(T-AOC)and glutathione(GSH)levels.Ion homeostasis analysis revealed a significant elevation in K+content and a marked reduction in Ca2+content in the gills.Metabolomic profiling identified 519 differentially expressed metabolites(DEMs),including 230 up-regulated and 289 down-regulated metabolites.These DEMs were primarily enriched in glycerophospholipid metabolism,glycerolipid metabolism,linoleic acid metabolism,and arachidonic acid metabolism.Furthermore,transcriptomic analysis identified 5159 differentially expressed genes(DEGs),including 2177 up-regulated and 2982 down-regulated genes.KEGG enrichment analysis indicated that these DEGs were significantly enriched in pathways such as arachidonic acid metabolism,glutathione metabolism,glycolysis/gluconeogenesis,and ferroptosis.Notably,the expression of genes encoding key rate-limiting enzymes in the glycolysis pathway,including hexokinase(hk),phosphofructokinase(pfk),and pyruvate kinase(pk),was significantly up-regulated,suggesting that ozone stress induced reprogramming of energy metabolism to cope with the adverse environment.Meanwhile,the significant up-regulation of genes in the ferroptosis pathway,including ferritin heavy chain 1(ferritin),transferrin receptor 1(tfr1),heme oxygenase 1(ho-1),and solute carrier family 7 member 11(slc7a11),indicated activation of ferroptosis.In conclusion,ozone exposure impaired the physiological functions of grass carp gills by inducing oxidative stress,disrupting ion and energy metabolic homeostasis,and activating the ferroptosis signaling pathway.This study provides crucial data for elucidating the toxicological mechanisms of ozone on fish gills and offers a theoretical basis for risk assessment and the establishment of technical guidelines in related fields.