University of Ottawa Heart Institute, University of Ottawa, Department of Biochemistry, Microbiology and Immunology, Ottawa, Ontario, Canada.
Curr Opin Lipidol. 2018 Apr;29(2):95-103. doi: 10.1097/MOL.0000000000000495.
The intestine is highly efficient at absorbing and packaging dietary lipids onto the structural protein apoB48 for distribution throughout the body. Here, we summarize recent advances into understanding the physiological and pharmacological actions of the proglucagon-derived peptides: glucagon like peptide 1 (GLP-1) and glucagon like peptide 2 (GLP-2) on intestinal lipoprotein secretion.
Several recent studies have elucidated mechanisms underlying the paradoxical effects of GLP-1 and GLP-2 on intestinal production of triglyceride-rich lipoproteins (TRLs). Both gut-derived peptides are secreted on an equimolar basis in response to the same nutrient stimulus. Despite neither receptor demonstrating clear localization to enterocytes, a single injection of a GLP-1R agonist rapidly decreases delivery of intestinally packaged fatty acids into the plasma, while conversely GLP-2 receptor (GLP-2R) activation acutely increases TRL concentrations in plasma.
The regulation of TRL secretion is dependent on the coordination of many processes: fatty acid availability uptake, assembly onto the apoB48 polypeptide backbone, secretion and reuptake, which the hormonal, neural, inflammatory and metabolic milieu can all strongly influence. Understanding of how GLP-1 and GLP-2 receptor agonists control TRL production has clinical importance given that GLP1R agonists were recently demonstrated not only to provide glycemic control but also to prevent major adverse cardiovascular events in patients with T2DM and the success of GLP-2R agonists in treating short bowel disease.
肠道高效地吸收和将膳食脂质包装到结构蛋白 apoB48 上,以便在体内分布。在此,我们总结了最近对胰高血糖素原衍生肽(GLP-1 和 GLP-2)对肠脂蛋白分泌的生理和药理作用的理解进展。
几项最近的研究阐明了 GLP-1 和 GLP-2 对肠道产生富含甘油三酯的脂蛋白(TRL)的矛盾作用的机制。两种肠道来源的肽都以等量的方式响应相同的营养刺激而分泌。尽管两个受体都没有明显定位于肠细胞,但单次注射 GLP-1R 激动剂可迅速降低肠道包装的脂肪酸进入血浆的输送,而相反,GLP-2 受体(GLP-2R)的激活则使 TRL 浓度在血浆中急剧增加。
TRL 分泌的调节取决于许多过程的协调:脂肪酸的可用性摄取、组装到 apoB48 多肽骨架上、分泌和再摄取,而激素、神经、炎症和代谢环境都可以强烈影响这些过程。鉴于 GLP1R 激动剂不仅提供血糖控制,而且预防 T2DM 患者的主要不良心血管事件,以及 GLP-2R 激动剂在治疗短肠综合征方面的成功,因此了解 GLP-1 和 GLP-2 受体激动剂如何控制 TRL 的产生具有临床重要性。