Acute liver carnitine palmitoyltransferase I overexpression recapitulates reduced palmitate oxidation of cardiac hypertrophy.
Acute liver carnitine palmitoyltransferase I overexpression recapitulates reduced palmitate oxidation of cardiac hypertrophy.
复制标题
急性肝肉毒碱棕榈酰转移酶 I 过度表达概括了心脏肥大的棕榈酸氧化减少。
DOI：
10.1161/circresaha.112.274456
复制
发表时间：
2013
影响因子：
20.1
通讯作者：
O'Donnell,JMichael
中科院分区：
文献类型：
--
作者：
Lewandowski,EDouglas;Fischer,SusanK;Fasano,Matthew;Banke,NatashaH;Walker,LoriA;Huqi,Alda;Wang,Xuerong;Lopaschuk,GaryD;O'Donnell,JMichael
Rationale:Muscle carnitine palmitoyltransferase I is predominant in the heart, but the liver isoform (liver carnitine palmitoyltransferase I [L-CPT1]) is elevated in hearts with low long chain fatty acid oxidation, such as fetal and hypertrophied hearts.Objective:This work examined the effect of acute L-CPT1 expression on the regulation of palmitate oxidation and energy metabolism in intact functioning rat hearts for comparison with findings in hypertrophied hearts.Methods and Results:L-CPT1 was expressed in vivo in rat hearts by coronary perfusion of Adv.cmv.L-CPT1 (L-CPT1, n=15) vs phosphate-buffered saline (PBS) infusion (PBS, n=7) or empty virus (empty, n=5). L-CPT1 was elevated 5-fold at 72 hours after Adv.cmv.L-CPT1 infusion (P<0.05), but muscle carnitine palmitoyltransferase I was unaffected. Despite similar tricarboxylic acid cycle rates, palmitate oxidation rates were reduced with L-CPT1 (1.12 ± 0.29 μmol/min per gram of dry weight, mean±SE) vs PBS (1.6 ± 0.34). Acetyl CoA production from palmitate was reduced with L-CPT1 (69 ± 0.02%;P<0.05; PBS=79 ± 0.01%; empty=81 ± 0.02%), similar to what occurs in hypertrophied hearts, and with no difference in malonyl CoA content. Glucose oxidation was elevated with L-CPT1 (by 60%). Surprisingly, L-CPT1 hearts contained elevated atrial natriuretic peptide, indicating induction of hypertrophic signaling.Conclusions:The results link L-CPT1 expression to reduced palmitate oxidation in a nondiseased adult heart, recapitulating the phenotype of reduced long chain fatty acid oxidation in cardiac hypertrophy. The implications are that L-CPT1 expression induces metabolic remodeling hypertrophic signaling and that regulatory factors beyond malonyl CoA in the heart regulate long chain fatty acid oxidation via L-CPT1.
