Transcriptome analysis of hepatopancreas revealed the role of autophagy under nitrite stress in Pacific white shrimp (Penaeus vannamei)

Nitrite constitutes a significant pollutant that impedes the growth of P. vannamei. Conventional treatments are primarily geared toward decreasing nitrite concentrations from an environmental standpoint. Nevertheless, investigating methodologies to enhance the ability of Pacific white shrimp to withstand nitrite-induced stresses on an individual basis remains an unexplored topic. The present study examines the impact of autophagy on Pacific white shrimp's response to high nitrite environments through rapamycin injection. The research findings indicate that activating autophagy can effectively enhance the survival rate of Pacific white shrimp under high nitrite conditions. Additionally, total hemocyte count (THC) results in the hemolymph demonstrate that autophagy can alleviate the reduction in blood cell count caused by nitrite stress. The transcriptome results show that upregulation of 718 genes and downregulation of 1071 genes after nitrite stress. The majority of these differentially expressed genes (DEGs) were related to physiological processes, including oxidative stress, energy metabolism, and lysosomes. In addition, there were 911 upregulated genes and 713 downregulated genes upon activation of autophagy. These DEGs are associated with immune responses, specifically involving glutathione metabolism, drug metabolism-cytochrome P450, and metabolism of xenobiotics by cytochrome P450, lysosomes, autophagy, phagosomes, melanization, and MAPK signaling pathways. These pathways can reduce oxidative stress and promote the metabolism of harmful substances in the body, in shrimp, thereby improving their survival rates. These findings provide new insights for research aimed at enhancing nitrite tolerance in Pacific white shrimp.