Effects of polystyrene nanoplastics on hormonal regulation and glucose metabolism of Pacific whiteleg shrimp (Litopenaeus vannamei)†

Abstract

Nanoplastics (NPs) as emerging pollutants pose a serious threat due to physiological effects on aquatic organisms, especially crustaceans. Therefore, the aim of the present study was to assess the effects of exposure to NPs on glucose metabolites, hormone content, glucose metabolism-related enzyme activities, and gene expression levels in Litopenaeus vannamei. The results showed that with increasing concentrations of NPs, lactic acid levels were significantly increased in the hemolymph and hepatopancreas, while glucose levels were significantly decreased; serum thyrotropin-releasing hormone levels were significantly increased, while serum levels of glucagon, insulin, and corticotropin-releasing hormones were significantly decreased; the activities of the glucose metabolism-related enzymes phosphofructokinase (PFK), phosphoenolpyruvate carboxykinase (PEPCK), and hepatopancreatic hexokinase (HK) initially increased and then decreased, while the activity of pyruvate kinase (PK) gradually decreased; the expression levels of HK, PFK, PK, fructose-1,6-bisphosphatase, glucose 6-phosphatase, and PEPCK first increased and then decreased, while the expression levels of glucose transporter 2 and glycogen synthase kinase-3 beta were significantly decreased. The results of metabolomics analysis showed that NPs may affect glucose metabolites via inhibition of the pentose phosphate pathway. These results suggest that NPs can interfere with glucose metabolism of L. vannamei by affecting glucose metabolites, hormone levels, enzyme activities, and gene expression levels. The results of this study offer valuable insights into the effects of exposure to NPs on the glucose metabolism of crustaceans.