Tissue-specific and substrate-specific mitochondrial bioenergetics in felinecardiac and skeletal muscles

Journal of Veterinary Medical Science

Flemming DELA²  Liselotte Bruun CHRISTIANSEN¹  Jørgen KOCH¹  Takashi YOKOTA² 

[1] Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, DK-1870 Frederiksberg, Denmark;X-lab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark

关键词: feline;    heart;    mitochondria;    oxidative phosphorylation;    skeletal muscle;   

DOI  :  10.1292/jvms.14-0573

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

References(39)Cited-By(1)No studies have investigated the mitochondrial function in permeabilized muscle fiberfrom cats. The aim of this study was to investigate tissue-specific and substrate-specificcharacteristics of mitochondrial oxidative phosphorylation (OXPHOS) capacity in felinepermeabilized oxidative muscle fibers. Biopsies of left ventricular cardiac muscle andsoleus muscle, a type I-rich oxidative skeletal muscle, were obtained from 15 healthydomestic cats. Enzymatic activity of citrate synthase (CS), a biomarker of mitochondrialcontent, was measured. Mitochondrial OXPHOS capacity with various kinds of non-fatty-acidsubstrates and fatty-acid substrate in permeabilized muscle fiber was measured by usinghigh-resolution respirometry. CS activity in the heart was 3 times higher than in thesoleus muscle. Mitochondrial state 3 respiration, ADP-stimulated respiration, with complexI-linked and complex I+II-linked substrates, respectively, was significantly higher in theheart than in the soleus muscle when normalized for muscle mass, but not for CS activity,indicating that greater capacity for mitochondrial OXPHOS with these non-fatty-acidsubstrates in the heart may depend on higher mitochondrial content. In contrast, thesoleus muscle had higher mitochondrial state 3 respiration with fatty acids than the heartwhen normalized for CS activity, indicating greater capacity for fatty-acid oxidation permitochondrion in the soleus. Our findings suggest that there are tissue- specific andsubstrate-specific quantitative and qualitative differences in mitochondrial OXPHOScapacity between the different types of oxidative muscles from cats.

【 授权许可】

Unknown