Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Hucheng Ring Road 999, Shanghai 201306, China.
Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Hucheng Ring Road 999, Shanghai 201306, China.
Comp Biochem Physiol A Mol Integr Physiol. 2023 Apr;278:111358. doi: 10.1016/j.cbpa.2022.111358. Epub 2022 Dec 23.
A new hypoxia-tolerant variety of blunt snout bream was obtained by successive breeding of the wild population, which markedly improved hypoxia tolerance. In this study, the hypoxia-tolerant variety was exposed to hypoxia (2.0 mg O·L) for 4, 7 days. The contents of blood biochemical indicators including the number of red blood cells (RBC), total cholesterol (T-CHO), total protein (TP), triglyceride (TG), glucose (GLU), and lactic acid (LD) increased significantly (P < 0.05) under hypoxia. The glycogen content in the liver and muscle decreased significantly (P < 0.05) and the LD content in the brain, muscle and liver increased significantly (P < 0.05) under hypoxia. The levels of oxidative stress-related indicators i.e., superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and total antioxidant capacity (T-AOC) also changed significantly (P < 0.05) in the heart, liver, and intestine of the new variety under hypoxia. Additionally, hypoxia has caused injuries to the heart, liver, and intestine, but it shows amazing repair ability during reoxygenation. The apoptotic cells and apoptosis rate in the heart, liver, and intestine increased under hypoxia. Under hypoxia, the expression of the B-cell lymphomas 2 (Bcl-2) gene in the heart, liver, and intestine was significantly (P < 0.05) down-regulated, while the expression of the BCL2-associated agonist of cell death (Bad) gene was significantly (P < 0.05) up-regulated. These results are of great significance for enriching the basic data of blunt snout bream new variety in response to hypoxia and promoting the healthy development of its culture industry.
通过对野生群体的连续选育，获得了一种新的耐低氧品种的钝吻鲂，其耐低氧能力显著提高。在本研究中，将耐低氧品种暴露于低氧（2.0 mg O·L）中 4、7 天。在低氧下，血液生化指标包括红细胞（RBC）数量、总胆固醇（T-CHO）、总蛋白（TP）、甘油三酯（TG）、葡萄糖（GLU）和乳酸（LD）的含量显著增加（P < 0.05）。在低氧下，肝和肌肉中的糖原含量显著降低（P < 0.05），脑、肌肉和肝脏中的 LD 含量显著增加（P < 0.05）。在低氧下，新品种的心、肝和肠中与氧化应激相关的指标，如超氧化物歧化酶（SOD）、丙二醛（MDA）、谷胱甘肽（GSH）、过氧化氢酶（CAT）和总抗氧化能力（T-AOC）的水平也发生了显著变化（P < 0.05）。此外，低氧对心、肝和肠造成了损伤，但在再氧合过程中表现出惊人的修复能力。在低氧下，心、肝和肠中的凋亡细胞和凋亡率增加。在低氧下，心、肝和肠中 B 细胞淋巴瘤 2（Bcl-2）基因的表达显著下调（P < 0.05），而 BCL2 相关细胞死亡激动剂（Bad）基因的表达显著上调（P < 0.05）。这些结果对于丰富钝吻鲂新品种对低氧的响应基础数据，促进其养殖产业的健康发展具有重要意义。
