Laboratory of Metabolic Manipulation of Herbivorous Animal Nutrition, College of Animal Science and Technology, Yangzhou University, Yangzhou, PR China.
Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, PR China.
J Nutr. 2020 Aug 1;150(8):2051-2060. doi: 10.1093/jn/nxaa133.
In nonruminants, many of the biological roles of l-arginine (Arg) at the intestinal level are mediated through the Arg-nitric oxide (Arg-NO) pathway. Whether the Arg-NO pathway is involved in controlling the immune response and viability in ovine intestinal epithelial cells (IOECs) is unclear.
The current study aimed to examine the role of the Arg-NO pathway in apoptosis, antioxidant capacity, and mitochondrial function of IOECs.
The IOECs were incubated in Arg-free DMEM supplemented with 150 μM Arg (CON) or 300 μM Arg (ARG) alone or with 350 μM Nw-nitro-l-arginine methyl ester hydrochloride (l-NAME) (CON + NAME, ARG + NAME) for 24 h. The reactive oxygen species (ROS) concentration, antioxidant capacity, and cell apoptotic percentage were determined.
Arg supplementation decreased (P < 0.05) the ROS concentration (38.9% and 22.7%) and apoptotic cell percentage (57.2% and 54.8%) relative to the CON and CON + NAME groups, respectively. Relative to the CON and ARG treatments, the l-NAME administration decreased (P < 0.05) the mRNA abundance of superoxide dismutase 2 (32% and 21.3%, respectively) and epithelial NO synthase (36% and 29.1%, respectively). Arg supplementation decreased (P < 0.05) the protein abundance of apoptosis antigen 1 (FAS) (52.0% and 43.9%) but increased (P < 0.05) those of nuclear respiratory factor 1 (31.3% and 22.9%) and inducible NO synthase (35.2% and 41.8%) relative to the CON and CON + NAME groups, respectively.
The inhibition of apoptosis in IOECs due to the increased supply of Arg is associated with the mitochondria- and FAS-dependent pathways through the activity of the Arg-NO pathway. The findings help elucidate the role of the Arg-NO pathway in IOEC growth and apoptosis.
在非反刍动物中，精氨酸（Arg）在肠道水平的许多生物学作用是通过 Arg-一氧化氮（Arg-NO）途径介导的。Arg-NO 途径是否参与控制绵羊肠道上皮细胞（IOEC）的免疫反应和活力尚不清楚。
本研究旨在探讨 Arg-NO 途径在 IOEC 细胞凋亡、抗氧化能力和线粒体功能中的作用。
将 IOEC 细胞在不含 Arg 的 DMEM 中孵育，补充 150 μM Arg（CON）或 300 μM Arg（ARG）单独或与 350 μM Nw-硝基-l-精氨酸甲酯盐酸盐（l-NAME）（CON+NAME、ARG+NAME）孵育 24 h。测定活性氧（ROS）浓度、抗氧化能力和细胞凋亡率。
Arg 补充降低了（P < 0.05）与 CON 和 CON+NAME 组相比，ROS 浓度（38.9%和 22.7%）和凋亡细胞百分比（57.2%和 54.8%）。与 CON 和 ARG 处理相比，l-NAME 给药降低了（P < 0.05）超氧化物歧化酶 2（32%和 21.3%）和上皮型一氧化氮合酶（36%和 29.1%）的 mRNA 丰度。Arg 补充降低了（P < 0.05）凋亡抗原 1（FAS）的蛋白丰度（52.0%和 43.9%），但增加了（P < 0.05）核呼吸因子 1（31.3%和 22.9%）和诱导型一氧化氮合酶（35.2%和 41.8%）的蛋白丰度与 CON 和 CON+NAME 组相比，分别。
由于 Arg 供应增加而导致 IOEC 细胞凋亡减少与 Arg-NO 途径的活性有关，涉及线粒体和 FAS 依赖性途径。这些发现有助于阐明 Arg-NO 途径在 IOEC 生长和凋亡中的作用。
