Characterization Of The Physiological And Molecular Response Of Hippocampus Abdominalis To Nanoplastic Pollution

The seahorse(Syngnathidae: Hippocampus)is a small bony fish that inhabits shallow coastal water and serves as a flagship species for environmental changes in nearshore marine ecosystems.Nanoplastic is a globally ubiquitous environmental pollutant that is small in volume and abundant,and is easily absorbed and ingested by marine organisms.Ingestion of nanoplastics not only affects the speed of feeding,digestion,and absorption of organisms,but also excessive accumulation of nanoplastics can affect growth and metabolism,and even lead to endocrine disruption,oxidative stress,and immune damage.This study aims to explore the physiological and immune system effects of nanoplastics on the pot-bellied seahorse(Hippocampus abdominalis),and to elucidate the molecular regulatory mechanisms involved.In this experiment,we chose two different concentrations(0.1 mg/L and 1 mg/L)of nanoplastics to evaluate their effects on hippocampal growth performance,tissue damage and antioxidant enzyme activity.The results showed that exposure to nanoplastics had negative effects on the development of respiratory system,liver and vision in the bulged seahorses.Specifically,the exposure to nanoplastics resulted in the up-regulation of the expression of SGK1,IGF1,SLC9a3r1 genes involved in osmotic pressure,and the down-regulation of KCNJ1 and Fx YD11 genes in the gills of distended seahorses,and affected the distribution and quantity of gene expression in the gills.In addition,we found that exposure to nanoplastics resulted in altered gene expression in the liver of the distended seahorses,particularly involving metabolic and detoxification-related pathways.Nanoplastics can inhibit the protein level and kinase activity of AMPK pathway.In this study,high-throughput transcriptomics analysis was used to explore the relationship between nanoplastics pollution and ocular surface damage.Nanoplastics may cause apoptosis and inactivation of retinal cells,affect the morphology and quantity of photoreceptor cells in retina,and thus affect the visual function of seahorses.These results indicate that exposure to nanoplastics has a wide range of effects on the physiological and immune systems of the distended seahorses,and the molecular regulatory mechanisms of its effects are clarified through transcriptomic analysis.In summary,this study provides theoretical support for a deeper understanding of the impact of nanoplastic pollution on nearshore marine ecosystems,and provides reference for the development of reasonable environmental protection policies.Moreover,the experimental results of this study have important implications for exploring the response mechanisms of seahorses to environmental pollution,providing a scientific basis for protecting marine biodiversity.