title: Dilation of human atria: increased diffusion restrictions for ADP, overexpression of hexokinase 2 and its coupling to oxidative phosphorylation in cardiomyocytes.
abstract: Cardiac energy metabolism with emphasis on mitochondria was addressed in atrial tissue from patients with overload-induced atrial dilation. Structural remodeling of dilated (D) atria manifested as intracellular accumulation of fibrillar aggregates, lipofuscin, signs of myolysis and autophagy. Despite impaired complex I dependent respiration and increased diffusion restriction for ADP, no changes regarding adenylate and creatine kinase occurred. We observed 7-fold overexpression of HK2 gene in D atria with concomitant 2-fold greater activation of mitochondrial oxygen consumption by glucose, which might represent an adaption to increased energy requirements and impaired mitochondrial function by effectively joining glycolysis and oxidative phosphorylation.
authors.affiliation: Institute of Biomedicine, Faculty of Medicine, University of Tartu, 19 Ravila Street, 50411 Tartu, Estonia. mart.roosimaa@ut.ee
authors.forename: Mart
authors.initials: M
authors.lastname: Roosimaa
authors.forename: Taavi
authors.initials: T
authors.lastname: Põdramägi
authors.forename: Lumme
authors.initials: L
authors.lastname: Kadaja
authors.forename: Arno
authors.initials: A
authors.lastname: Ruusalepp
authors.forename: Kalju
authors.initials: K
authors.lastname: Paju
authors.forename: Raivo
authors.initials: R
authors.lastname: Puhke
authors.forename: Margus
authors.initials: M
authors.lastname: Eimre
authors.forename: Ehte
authors.initials: E
authors.lastname: Orlova
authors.forename: Andres
authors.initials: A
authors.lastname: Piirsoo
authors.forename: Nadežda
authors.initials: N
authors.lastname: Peet
authors.forename: Frank N
authors.initials: FN
authors.lastname: Gellerich
authors.forename: Enn
authors.initials: E
authors.lastname: Seppet
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism*; D000369:Aged, 80 and over; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology*; D005260:Female; D006593:Hexokinase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000378:metabolism / Q000502:physiology*; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000502:physiology*; D010085:Oxidative Phosphorylation
chemical_list: D000244:Adenosine Diphosphate; D006593:Hexokinase