An 8 weeks feeding trial and a cell culture were conducted to determine the effects of hypoxia and vitamin C (Vc) on muscle development of channel catfish (Ictalurus punctatus). In vivo, the channel catfish (average initial weight 14.50 ± 0.15 g) were divided into four groups, normoxia (DO 7.5 ± 0.5 mg/L) with 50 mg/kg of Vc (N50), hypoxia (DO 5.0 ± 0.5 mg/L) with 50 mg/kg of Vc (H50), hypoxia with 250 mg/kg of Vc (H250), and hypoxia with 500 mg/kg of Vc (H500). Results indicated that the specific growth rate (SGR) of fish in the H50 was significantly lower than the N50 and H250 (P < 0.05). The mean diameter of myofibers and sarcomere lengths were significantly increased in the H50 group compared to the N50, H250, and H500 groups (P < 0.05). The fiber density was significantly increased in the H50 than in the N50. Transcriptome analysis showed that paired box 3 (pax3) and myogenic regulatory factors (MRFs) expression and Sonic hedgehog (Shh) pathways associated with muscle development were significantly affected in the N50 and H250 group compared to the H50 (P < 0.05). A subsequent study showed that the gene expression of myogenic factor 5 (myf5) and myoblast determination protein (myod) were significantly decreased, and myogenin (myog) was significantly increased in the H50 group compared to the N50 (P < 0.05). The level of Hif-1α was significantly higher in H50 than in N50 but significantly lower in H50 than in H250 and H500 (P < 0.05). The level of Pax3 was significantly lower in H50 than the N50 (P < 0.05). In vitro, L6 was incubated with 400 μM of CoCl₂·6H₂O and 100 μM of defetoxamine (DFO) for 24 h, respectively. The results showed that the Hif-1α level was significantly increased (P < 0.05). Under this condition, the levels of Pax3, Shh, and glioma-associated oncogene homolog (Gli), were found to be significantly decreased (P < 0.05). A subsequent study found that Vc at 0.25 mg/L significantly increased the level of Gli under hypoxia. In conclusion, hypoxia inhibits myofiber proliferation and promotes myofiber differentiation. Vc can improve myofiber development under hypoxia, which may be related to the activation of the Shh-Gli signaling pathway.

进行了 8 周的喂养试验和细胞培养，以确定缺氧和维生素 C (Vc) 对鲶鱼 ( Ictalurus punctatus ) 肌肉发育的影响。在体内，将鲶鱼（平均初始体重 14.50 ± 0.15 g）分为四组，常氧（DO 7.5 ± 0.5 mg/L）和 50 mg/kg Vc（N50），缺氧（DO 5.0 ± 0.5 mg/ L) 50 mg/kg Vc (H50)，缺氧 250 mg/kg Vc (H250)，缺氧 500 mg/kg Vc (H500)。结果表明，H50的鱼类比生长率（SGR）显着低于N50和H250（P  < 0.05）。与 N50、H250 和 H500 组相比，H50 组的肌纤维平均直径和肌节长度显着增加（P < 0.05)。H50的纤维密度比N50显着增加。转录组分析显示，与 H50 相比，N50 和 H250 组的配对框 3 ( pax3 ) 和肌源性调节因子 ( MRFs ) 表达以及与肌肉发育相关的 Sonichedgehog (Shh) 通路受到显着影响（P  < 0.05）。随后的一项研究表明，与 N50 相比，H50 组肌源性因子 5 ( myf5 ) 和成肌细胞决定蛋白 ( myod)基因表达显着降低，肌细胞生成素 ( myog ) 显着升高 ( P < 0.05)。Hif-1α水平H50显着高于N50，H50显着低于H250和H500（P  < 0.05）。H50 的 Pax3 水平显着低于 N50 ( P  < 0.05)。在体外，L6 分别与 400 μM C ​​oCl ₂ ·6H ₂ O 和 100 μM 去甲氧胺 (DFO) 孵育 24 小时。结果显示Hif-1α水平显着升高（P  < 0.05）。在这种情况下，发现 Pax3、Shh 和胶质瘤相关癌基因同源物 (Gli) 的水平显着降低（P < 0.05)。随后的一项研究发现，0.25 mg/L 的 Vc 显着增加了缺氧条件下的 Gli 水平。总之，缺氧抑制肌纤维增殖并促进肌纤维分化。Vc可促进缺氧条件下肌纤维发育，这可能与Shh-Gli信号通路的激活有关。