title: Intramyocardial lipid accumulation in the failing human heart resembles the lipotoxic rat heart.
abstract: In animal models of lipotoxicity, accumulation of triglycerides within cardiomyocytes is associated with contractile dysfunction. However, whether intramyocardial lipid deposition is a feature of human heart failure remains to be established. We hypothesized that intramyocardial lipid accumulation is a common feature of non-ischemic heart failure and is associated with changes in gene expression similar to those found in an animal model of lipotoxicity. Intramyocardial lipid staining with oil red O and gene expression analysis was performed on heart tissue from 27 patients (9 female) with non-ischemic heart failure. We determined intramyocardial lipid, gene expression, and contractile function in hearts from 6 Zucker diabetic fatty (ZDF) and 6 Zucker lean (ZL) rats. Intramyocardial lipid overload was present in 30% of non-ischemic failing hearts. The highest levels of lipid staining were observed in patients with diabetes and obesity (BMI>30). Intramyocardial lipid deposition was associated with an up-regulation of peroxisome proliferator-activated receptor alpha (PPARalpha) -regulated genes, myosin heavy chain beta (MHC-beta), and tumor necrosis factor alpha (TNF-alpha). Intramyocardial lipid overload in the hearts of ZDF rats was associated with contractile dysfunction and changes in gene expression similar to changes found in failing human hearts with lipid overload. Our findings identify a subgroup of patients with heart failure and severe metabolic dysregulation characterized by intramyocardial triglyceride overload and changes in gene expression that are associated with contractile dysfunction.
authors.affiliation: Department of Internal Medicine, Division of Cardiology, University of Texas Houston-Medical School, Houston, TX 77030, USA.
authors.forename: Saumya
authors.initials: S
authors.lastname: Sharma
authors.forename: Julia V
authors.initials: JV
authors.lastname: Adrogue
authors.forename: Leonard
authors.initials: L
authors.lastname: Golfman
authors.forename: Ivan
authors.initials: I
authors.lastname: Uray
authors.forename: John
authors.initials: J
authors.lastname: Lemm
authors.forename: Keith
authors.initials: K
authors.lastname: Youker
authors.forename: George P
authors.initials: GP
authors.lastname: Noon
authors.forename: O H
authors.initials: OH
authors.lastname: Frazier
authors.forename: Heinrich
authors.initials: H
authors.lastname: Taegtmeyer
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002303:Cardiac Output, Low / Q000150:complications / Q000378:metabolism* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D009218:Myosins / Q000096:biosynthesis / Q000235:genetics; D009765:Obesity / Q000150:complications; D051381:Rats; D011924:Rats, Zucker; D012518:Sarcomeres / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics
chemical_list: D014280:Triglycerides; D014409:Tumor Necrosis Factor-alpha; D009218:Myosins