Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China.
Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China.
In Vitro Cell Dev Biol Anim. 2024 Oct;60(9):1009-1020. doi: 10.1007/s11626-024-00942-y. Epub 2024 Aug 2.
The promotion of gut health, a pervasive problem in modern animal husbandry, positively affects organismal health, productivity, and economics. Porcine intestinal epithelial cells (IPEC-J2) continuously proliferate to maintain intestinal homeostasis, including barrier, immune, and absorptive functions. Gut homeostasis is fundamental to organismal health. ADP-ribosylation factor 1 (Arf1), a small GTPase, plays a crucial role in coordinating mTORC1 in response to nutrients, especially amino acid availability in the gut. mTORC1 is the central hub of proliferation. Thus, it seems likely that Arf1 promotes IPEC-J2 cell proliferation. However, the exact role of Arf1 in the porcine gut remains unclear. Therefore, we evaluated the functional role and possible mechanisms of Arf1 in the porcine intestine through Arf1 overexpression and knockdown in IPEC-J2 cells. Arf1 overexpression and knockdown significantly enhanced and inhibited, respectively, IPEC-J2 cell viability, and PCNA expression varied with Arf1 expression. Moreover, the proportion of Ki67-positive cells was significantly greater in the Arf1-overexpressing group than in the control group. These results suggest that Arf1 improves IPEC-J2 cell proliferation. The underlying mechanism was explored by Western blotting. Arf1 overexpression and knockdown significantly enhanced and suppressed, respectively, the levels of p-S6K1 and p-RPS6, which are key downstream targets of the mTORC1 signaling pathway. Collectively, our findings reveal the role of the Arf1-mTORC1 axis in IPEC-J2 cell proliferation and its potential function in regulating intestinal homeostasis and health.
促进肠道健康是现代畜牧业普遍存在的问题，它对机体健康、生产性能和经济效益有积极影响。猪肠上皮细胞（IPEC-J2）不断增殖以维持肠道内环境稳定，包括屏障、免疫和吸收功能。肠道内环境稳定是机体健康的基础。ADP-核糖基化因子 1（Arf1）是一种小分子 GTP 酶，在协调 mTORC1 对营养物质特别是肠道中氨基酸可用性的反应中起着至关重要的作用。mTORC1 是增殖的中心枢纽。因此，Arf1 促进 IPEC-J2 细胞增殖似乎是合理的。然而，Arf1 在猪肠道中的确切作用尚不清楚。因此，我们通过在 IPEC-J2 细胞中转染 Arf1 过表达和敲低来评估 Arf1 在猪肠道中的功能作用和可能的机制。Arf1 过表达和敲低分别显著增强和抑制了 IPEC-J2 细胞的活力，PCNA 表达随 Arf1 表达而变化。此外，Arf1 过表达组中 Ki67 阳性细胞的比例明显高于对照组。这些结果表明，Arf1 可改善 IPEC-J2 细胞的增殖。通过 Western blot 进一步探讨了其潜在机制。Arf1 过表达和敲低分别显著增强和抑制了 mTORC1 信号通路的关键下游靶标 p-S6K1 和 p-RPS6 的水平。综上所述，我们的研究结果揭示了 Arf1-mTORC1 轴在 IPEC-J2 细胞增殖中的作用及其在调节肠道内环境稳定和健康方面的潜在功能。
