Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China.
College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China.
Int J Mol Sci. 2021 Dec 13;22(24):13379. doi: 10.3390/ijms222413379.
Methionine restriction reduces animal lipid deposition. However, the molecular mechanism underlying how the body reacts to the condition and regulates lipid metabolism remains unknown. In this study, a feeding trial was performed on rice field eel with six isonitrogenous and isoenergetic feeds that included different levels of methionine (0, 2, 4, 6, 8, and 10 g/kg). Compared with M0 (0 g/kg), the crude lipid and crude protein of increased markedly in M8 (8 g/kg) ( < 0.05), serum (total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and non-esterified free fatty acids), and hepatic contents (hepatic lipase, apolipoprotein-A, fatty acid synthetase, total cholesterol, triglyceride, and lipoprteinlipase). However, in the serum, very-low-density lipoprotein and hepatic contents (hormone-sensitive triglyceride lipase, Acetyl CoA carboxylase, carnitine palmitoyltransterase, and mirosomal triglygeride transfer protein) decreased markedly in M8 ( < 0.05). The contents of hepatic C18:2n-6, C22:6n-3, and n-3PUFA in the M8 group were significantly higher than those in M0 ( < 0.05), and the contents of lipid droplets in M8 were higher than those in M0. Compared with M0, the hepatic gcn2, eif2α, and were remarkably downregulated in M8, while and were markedly upregulated in M8. Moreover, hepatic SREBP1 and FAS protein expression were upregulated significantly in M8 ( < 0.01). In short, methionine restriction decreased the lipid deposition of , especially for hepatic lipid deposition, and mainly downregulated hepatic fatty acid metabolism. Besides, could be activated under methionine restriction.
蛋氨酸限制可减少动物的脂质沉积。然而，机体如何对此条件做出反应以及调节脂质代谢的分子机制尚不清楚。在这项研究中，我们在稻田鳗上进行了一项饲养试验，使用了六种等氮和等能的饲料，其中包含不同水平的蛋氨酸（0、2、4、6、8 和 10 g/kg）。与 M0（0 g/kg）相比，M8（8 g/kg）中的粗脂肪和粗蛋白显著增加（<0.05），血清（总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和非酯化游离脂肪酸）和肝组织（肝脂肪酶、载脂蛋白-A、脂肪酸合成酶、总胆固醇、甘油三酯和脂蛋白脂肪酶）中的含量也是如此。然而，在血清中，极低密度脂蛋白和肝组织（激素敏感甘油三酯脂肪酶、乙酰辅酶 A 羧化酶、肉碱棕榈酰转移酶和微粒体甘油三酯转移蛋白）中的含量在 M8 中显著降低（<0.05）。M8 组肝组织中 C18:2n-6、C22:6n-3 和 n-3PUFA 的含量明显高于 M0（<0.05），且 M8 中的脂滴含量高于 M0。与 M0 相比，M8 中肝组织的 gcn2、eif2α 和 显著下调，而 和 显著上调。此外，M8 中肝组织 SREBP1 和 FAS 蛋白表达显著上调（<0.01）。总之，蛋氨酸限制可减少 的脂质沉积，尤其是肝脂质沉积，主要下调肝内脂肪酸代谢。此外，在蛋氨酸限制下 可以被激活。
