Section of Vascular Surgery, Department of Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO
Section of Vascular Surgery, Department of Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO.
Diabetes. 2021 Feb;70(2):549-561. doi: 10.2337/db20-0635. Epub 2020 Nov 19.
De novo phospholipogenesis, mediated by choline-ethanolamine phosphotransferase 1 (CEPT1), is essential for phospholipid activation of transcription factors such as peroxisome proliferator-activated receptor α (PPARα) in the liver. Fenofibrate, a PPARα agonist and lipid-lowering agent, decreases amputation incidence in patients with diabetes. Because we previously observed that CEPT1 is elevated in carotid plaque of patients with diabetes, we evaluated the role of CEPT1 in peripheral arteries and PPARα phosphorylation (Ser12). CEPT1 was found to be elevated in diseased lower-extremity arterial intima of individuals with peripheral arterial disease and diabetes. To evaluate the role of in the endothelium, we engineered a conditional endothelial cell (EC)-specific deletion of via induced ---mediated recombination (/ ). / ECs demonstrated decreased proliferation, migration, and tubule formation, and / mice had reduced perfusion and angiogenesis in ischemic hind limbs. Peripheral ischemic recovery and PPARα signaling were further compromised by streptozotocin-induced diabetes and ameliorated by feeding fenofibrate. endoribonuclease-prepared siRNA decreased PPARα phosphorylation in ECs, which was rescued with fenofibrate but not PC16:0/18:1. Unlike / mice, / mice did not demonstrate hind-paw perfusion recovery after feeding fenofibrate. Therefore, we demonstrate that CEPT1 is essential for EC function and tissue recovery after ischemia and that fenofibrate rescues CEPT1-mediated activation of PPARα.
从头合成磷脂,由胆碱-乙醇胺磷酸转移酶 1(CEPT1)介导,对于肝脏中转录因子如过氧化物酶体增殖物激活受体α(PPARα)的磷脂激活至关重要。非诺贝特是一种 PPARα 激动剂和降脂剂,可降低糖尿病患者的截肢发生率。因为我们之前观察到 CEPT1 在糖尿病患者的颈动脉斑块中升高,所以我们评估了 CEPT1 在周围动脉和 PPARα 磷酸化(Ser12)中的作用。在患有周围动脉疾病和糖尿病的个体的下肢动脉内膜病变中发现 CEPT1 升高。为了评估在血管内皮细胞中的作用,我们通过诱导型---介导的重组(/)工程构建了内皮细胞(EC)特异性的 CEPT1 缺失(/)。/ EC 表现出增殖、迁移和小管形成减少,/ 小鼠在缺血后肢中的灌注和血管生成减少。外周缺血恢复和 PPARα 信号进一步受到链脲佐菌素诱导的糖尿病的损害,并通过喂食非诺贝特得到改善。内源性核糖核酸酶制备的 siRNA 降低了 EC 中的 PPARα 磷酸化,这可以通过非诺贝特挽救,但不能通过 PC16:0/18:1 挽救。与/ 小鼠不同,/ 小鼠在喂食非诺贝特后没有表现出后肢灌注恢复。因此,我们证明 CEPT1 对于缺血后 EC 功能和组织恢复至关重要,并且非诺贝特可以挽救 CEPT1 介导的 PPARα 激活。