Effects of acute hypoxia and reoxygenation on oxygen sensors, respiratory metabolism, oxidative stress, and apoptosis in hybrid yellow catfish “Huangyou-1”

Abstract

The regulation mechanism of the hybrid yellow cat sh "Huangyou-1" was assessed under conditions of hypoxia and reoxygenation by examination of oxygen sensors and by monitoring respiratory metabolism, oxidative stress, and apoptosis. The expressions of genes related to oxygen sensors (HIF-1α, HIF-2α, VHL, HIF-1β, PHD2, and FIH-1) were upregulated in the brain and liver during hypoxia, and recovered compared with control upon reoxygenation. The expressions of genes related to glycolysis (HK1, PGK1, PGAM2, PFK, and LDH) were increased during hypoxia and then recovered compared with control upon reoxygenation. The expressions of CS and SDH were lower than those of control during hypoxia and increased upon reoxygenation. Under hypoxic conditions, the expressions of genes related to oxidative stress (SOD1, SOD2, GSH-Px, and CAT) and the activity of antioxidant enzymes (SOD, CAT, and GSH-Px) and MDA were upregulated compared with control. The expressions of genes related to apoptosis (Apaf-1, Bax, Caspase 3, Caspase 9, and p53) were higher than those in control during hypoxic exposure, while the expressions of Bcl-2 and Cyt C were decreased. The ndings of the transcriptional analyses will provide insights into the molecular mechanisms of hybrid yellow cat sh "Huangyou-1" under conditions of hypoxia and reoxygenation.

Dietary Clostridium butyricum Improves Growth Performance and Resistance to Ammonia Stress in Yellow Catfish (Pelteobagrus fulvidraco)

“…Yellow catfish (Pelteobagrus fulvidraco) is an economic important omnivorous freshwater fish species in China. It is sensitive to environmental stressors such as ammonia [26], nitrite [27], hypoxia [28], and high temperature [29]. Therefore, the aim of this study was to investigate the effects of CB on growth performance, intestinal morphology, mRNA levels of tight junction proteins and immune-related genes, and resistance to ammonia stress in juvenile yellow catfish (Pelteobagrus fulvidraco).…”

Gill and Liver Transcript Expression Changes Associated With Gill Damage in Atlantic Salmon (Salmo salar)

“…Also, the PCA showed that pgam2 was the top contributing biomarker on separating GS2 individuals from all other gill scores on PC1 ( Figure 9D ). In pufferfish ( Takifugu fasciatus ) and in hybrid yellow catfish “Huangyou-1”, higher mRNA levels of pgam2 and other glycolysis-related biomarkers were observed responding to hypoxia in the liver and brain tissues ( 78 , 79 ), posing a question to whether the gill pgam2 upregulation found in the present study points to impaired tissue oxygenation due to injury. Conversely, pgam2 was downregulated in the skin of Atlantic salmon infected with sea lice ( 80 ).…”

Antioxidant and anti-stress properties of postbiotics produced by Lysinibacillus macroides G117

“…SOD has three forms, SOD1, SOD2, and SOD3, which decompose superoxide free radicals in the cytoplasm, mitochondria, and extracellular fluid, respectively, and are important antioxidant enzymes [65] . MDA, which is produced by the peroxidation of polyunsaturated fatty acids, is also an important marker of oxidative stress [ 66 , 67 ]. In this study, significant improvements were observed in antioxidant-related enzymes (e.g.…”