School of Marine Sciences, Ningbo University, Ningbo 315832, China.
College of Biological and Chemical Engineering, Hunan Engineering Technology Research Center for Amphibian and Reptile Resource Protection and Product Processing, Changsha University, Changsha 410022, China.
Genes (Basel). 2024 Jun 26;15(7):840. doi: 10.3390/genes15070840.
Starvation is one of the main stresses for fish due to food shortage, the evasion of predators, and intraspecific competition. This research evaluated the impact of brief fasting periods on reactive oxygen species (ROS) levels, antioxidant response, mRNA expression of antioxidants, autophagy-related signaling genes, and autophagosome development in the muscle tissue of rice flower carp. Following a three-day fasting period, the levels of ROS and MDA rose. Additionally, after 3 d of fasting, there was a notable upregulation of and significant increases in the levels of GSH and the activities of enzymes such as SOD, CAT, GST, GR, and GPX, while the expression of the autophagy marker gene did not change ( < 0.05). After 7 d of fasting, the content of the ROS, the activity of SOD and GR, and the GSH content reached the maximum ( < 0.05). Concurrently, there was a significant rise in the quantity of autophagosomes. An RT-qPCR analysis revealed that seven d of starvation significantly elevated the mRNA expression of genes associated with the initiation and expansion of autophagosome membranes, vesicle recycling, and cargo recruitment, including , , , , , , , , and . After feeding resumed for 3 d, the mRNA level of , , , , , , and still remained at a high level. The LC3II protein reached its highest level. All autophagy-related gene expression decreased in the 7-day resumed feeding group. Our data implied that short-term fasting can cause oxidative stress and disrupt the antioxidant system first and then induce autophagy in the muscles of rice flower carp. These findings shed light on how fasting affects muscle homeostasis in fish. ROS-induced autophagy of the skeletal muscle may confer the resistance of rice flower carp to short-term fasting.
饥饿是鱼类面临的主要压力之一，原因包括食物短缺、逃避捕食者和种内竞争。本研究评估了短暂禁食期对稻花鱼肌肉组织中活性氧（ROS）水平、抗氧化反应、抗氧化剂基因 mRNA 表达、自噬相关信号基因和自噬体发育的影响。经过三天的禁食期后，ROS 和 MDA 的水平上升。此外，禁食 3 天后， 和 GSH 的水平显著上调，SOD、CAT、GST、GR 和 GPX 等酶的活性显著增加，而自噬标记基因 的表达没有变化（<0.05）。禁食 7 天后，ROS 含量、SOD 和 GR 活性以及 GSH 含量达到最大值（<0.05）。同时，自噬体的数量显著增加。RT-qPCR 分析显示，饥饿 7 天显著上调了与自噬体膜起始和扩展、囊泡回收和货物募集相关的基因的 mRNA 表达，包括 、 、 、 、 、 、 、 和 。恢复喂养 3 天后， 、 、 、 、 、 和 的 mRNA 水平仍然保持在较高水平。LC3II 蛋白水平达到最高。在 7 天恢复喂养组中，所有自噬相关基因的表达均下降。我们的数据表明，短期禁食会首先引起稻花鱼肌肉的氧化应激和破坏抗氧化系统，然后诱导自噬。这些发现揭示了禁食如何影响鱼类的肌肉稳态。ROS 诱导的骨骼肌自噬可能使稻花鱼能够抵抗短期禁食。
