School of Nutrition and Health Sciences, Taipei Medical University, Taipei 11031, Taiwan.
Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8857, Japan.
Int J Mol Sci. 2023 May 16;24(10):8845. doi: 10.3390/ijms24108845.
This study investigated the beneficial effects of epidermal growth factor (EGF) on muscle loss in rats with chronic ethanol feeding. Six-week-old male Wistar rats were fed either a control liquid diet without EGF (C group, = 12) or EGF (EGF-C group, = 18) for two weeks. From the 3rd to 8th week, the C group was divided into two groups. One was continually fed with a control liquid diet (C group), and the other one was fed with an ethanol-containing liquid diet (E group); moreover, the EGF-C group was divided into three groups, such as the AEGF-C (continually fed with the same diet), PEGF-E (fed with the ethanol-containing liquid diet without EGF), and AEGF-E (fed with the ethanol-containing liquid diet with EGF). As a result, the E group had significantly higher plasma ALT and AST, endotoxin, ammonia, and interleukin 1b (IL-1b) levels, along with liver injuries, such as hepatic fatty changes and inflammatory cell infiltration. However, plasma endotoxin and IL-1b levels were significantly decreased in the PEGF-E and AEGF-E groups. In addition, the protein level of muscular myostatin and the mRNA levels of forkhead box transcription factors (FOXO), muscle RING-finger protein-1 (MURF-1) and atorgin-1 was increased considerably in the E group but inhibited in the PEGF-E and AEGF-E groups. According to the principal coordinate analysis findings, the gut microbiota composition differed between the control and ethanol liquid diet groups. In conclusion, although there was no noticeable improvement in muscle loss, EGF supplementation inhibited muscular protein degradation in rats fed with an ethanol-containing liquid diet for six weeks. The mechanisms might be related to endotoxin translocation inhibition, microbiota composition alteration as well as the amelioration of liver injury. However, the reproducibility of the results must be confirmed in future studies.
本研究旨在探讨表皮生长因子(EGF)对慢性乙醇喂养大鼠肌肉减少的有益作用。6 周龄雄性 Wistar 大鼠分别给予不含 EGF 的对照液体饮食(C 组,n = 12)或 EGF 液体饮食(EGF-C 组,n = 18)喂养 2 周。从第 3 周到第 8 周,C 组分为两组,一组继续给予对照液体饮食(C 组),另一组给予含乙醇的液体饮食(E 组);此外,EGF-C 组分为三组,即 AEGF-C(继续给予相同饮食)、PEGF-E(给予不含 EGF 的含乙醇液体饮食)和 AEGF-E(给予含 EGF 的含乙醇液体饮食)。结果显示,E 组的血浆 ALT 和 AST、内毒素、氨和白细胞介素 1b(IL-1b)水平显著升高,同时伴有肝损伤,如肝脂肪变性和炎症细胞浸润。然而,PEGF-E 和 AEGF-E 组的血浆内毒素和 IL-1b 水平显著降低。此外,E 组肌肉肌生成抑制素蛋白水平和叉头框转录因子(FOXO)、肌肉环指蛋白-1(MURF-1)和 Atorgin-1 的 mRNA 水平显著升高,但在 PEGF-E 和 AEGF-E 组中受到抑制。根据主坐标分析结果,与对照和乙醇液体饮食组相比,肠道微生物群组成存在差异。综上所述,尽管 EGF 补充对六周含乙醇液体饮食喂养的大鼠肌肉减少没有明显改善,但能抑制肌肉蛋白降解。其机制可能与内毒素易位抑制、微生物群组成改变以及肝损伤改善有关。然而,这些结果的重现性必须在未来的研究中得到证实。