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Effects of Nitrite Stress on Growth, Glycolipid Metabolism, and Hepatic Metabolome in Spotted Seabass (Lateolabrax maculatus) Under High-Temperature Conditions
by
, , ,
Juan Gao
, 
Shi Cao
,
Chen Shen
,
Jian Zhang
,
Ling Wang
,
Xueshan Li
,
Kangle Lu
,
Chunxiao Zhang
and
Kai Song
* Laboratory of Aquatic animal Nutrition, Fisheries College, Jimei University, Xiamen 361021, China
*
Author to whom correspondence should be addressed.
Animals 2025, 15(13), 1870; https://doi.org/10.3390/ani15131870
Submission received: 26 May 2025
/
Revised: 20 June 2025
/
Accepted: 23 June 2025
/
Published: 24 June 2025
(This article belongs to the Special Issue Novel Insights into Lipid Metabolism in Aquatic Animals)
Simple Summary
This study investigated how nitrite, a common pollutant in aquaculture water, affects the health and growth of the spotted seabass (Lateolabrax maculatus) when they are raised in high-temperature conditions at 33 °C (the optimal keeping temperature range of 26–27 °C). The fish were exposed to different levels of nitrite, and their growth, survival, and changes in their liver and blood were tracked over four weeks. The results showed that higher nitrite levels caused the fish to grow more slowly, have lower survival rates, and store less lipid and sugar in their bodies. Their livers showed signs of stress, with more substances related to energy breakdown and fewer signs of fat production. Key genes responsible for storing and using energy were also affected. Detailed analysis of the liver showed that important energy pathways were disrupted. Overall, the study found that nitrite stress makes it harder for the spotted seabass to grow and survive in warm water by forcing their bodies to break down fats and produce sugar to meet energy needs. These findings help fish farmers understand the risks of poor water quality and can guide better practices to protect fish health, especially as temperatures rise due to climate change.
Abstract
Nitrite is a common pollutant in aquaculture systems and can pose serious threats to fish health, especially under high-temperature conditions. This study aimed to investigate the impact of nitrite stress on the growth, glycolipid metabolism, and hepatic metabolomic profiles in the spotted seabass fry (Lateolabrax maculatus) under elevated temperature conditions at 33 °C. A total of 450 fish (28.52 ± 0.84 g) were randomly distributed into nine tanks and exposed to three nitrite concentrations (0, 8, and 16 mg/L), with samples collected on days 1, 3, 7, 14, 21, and 28. Results showed that higher nitrite levels significantly reduced final body weight, weight gain, survival rate, hepatosomatic index, and viscerosomatic index. Blood glucose and triglyceride levels, whole-body crude lipid, liver total cholesterol, and hepatic glycogen content also declined significantly under higher nitrite stress. In contrast, hepatic lactate and lactate dehydrogenase increased in the high-nitrite group. Gene expression analysis revealed suppressed lipid synthesis and enhanced lipolysis under nitrite exposure. Metabolomic analysis further demonstrated disruptions in key energy-related pathways, including the TCA cycle, pentose phosphate pathway, and insulin signaling. These findings indicate that nitrite stress impairs growth and energy metabolism in spotted seabass, which respond by mobilizing energy reserves to cope with combined stress of high temperature and nitrite.
Keywords:
spotted seabass; nitrite stress; high temperature; growth; glycolipid metabolism
