Acute effect of fatty acids on metabolism and mitochondrial coupling in skeletal muscle.
Acute effects of free fatty acids (FFA) were investigated on: (1) glucose oxidation, and UCP-2 and -3 mRNA and protein levels in 1 h incubated rat soleus and extensor digitorium longus (EDL) muscles, (2) mitochondrial membrane potential in cultured skeletal muscle cells, (3) respiratory activity and transmembrane electrical potential in mitochondria isolated from rat skeletal muscle, and (4) oxygen consumption by anesthetized rats. Long-chain FFA increased both basal and insulin-stimulated glucose oxidation in incubated rat soleus and EDL muscles and reduced mitochondrial membrane potential in C2C12 myotubes and rat skeletal muscle cells. Caprylic, palmitic, oleic, and linoleic acid increased O(2) consumption and decreased electrical membrane potential in isolated mitochondria from rat skeletal muscles. FFA did not alter UCP-2 and -3 mRNA and protein levels in rat soleus and EDL muscles. Palmitic acid increased oxygen consumption by anesthetized rats. These results suggest that long-chain FFA acutely lead to mitochondrial uncoupling in skeletal muscle.
Hirabara
Sandro M
SM
Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Cidade Universitária, Av. Professor Lineu Prestes, 1524 Butantã, São Paulo, SP 05508-900, Brazil.
Silveira
Leonardo R
LR
Alberici
Luciane C
LC
Leandro
Carol V G
CV
Lambertucci
Rafael H
RH
Polimeno
Gisele C
GC
Cury Boaventura
Maria F
MF
Procopio
Joaquim
J
Vercesi
Anibal E
AE
Curi
Rui
R
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003065:Coenzyme A / Q000378:metabolism; D005227:Fatty Acids / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism*; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D007473:Ion Channels; D019787:Linoleic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008931:Mitochondria, Muscle / Q000187:drug effects* / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000187:drug effects; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D032342:Muscle Cells / Q000187:drug effects; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D019301:Oleic Acid / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects; D019308:Palmitic Acid / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D051381:Rats; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3
D002352:Carrier Proteins; D005227:Fatty Acids; D007328:Insulin; D007473:Ion Channels; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; C000604391:Ucp2 protein, rat; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3; D019301:Oleic Acid; D019308:Palmitic Acid; D019787:Linoleic Acid; D005947:Glucose; D003065:Coenzyme A