Greater transport efficiencies of the membrane fatty acid transporters FAT/CD36 and FATP4 compared with FABPpm and FATP1 and differential effects on fatty acid esterification and oxidation in rat skeletal muscle.
In selected mammalian tissues, long chain fatty acid transporters (FABPpm, FAT/CD36, FATP1, and FATP4) are co-expressed. There is controversy as to whether they all function as membrane-bound transporters and whether they channel fatty acids to oxidation and/or esterification. Among skeletal muscles, the protein expression of FABPpm, FAT/CD36, and FATP4, but not FATP1, correlated highly with the capacities for oxidative metabolism (r>or=0.94), fatty acid oxidation (r>or=0.88), and triacylglycerol esterification (r>or=0.87). We overexpressed independently FABPpm, FAT/CD36, FATP1, and FATP4, within a normal physiologic range, in rat skeletal muscle, to determine the effects on fatty acid transport and metabolism. Independent overexpression of each fatty acid transporter occurred without altering either the expression or plasmalemmal content of other fatty acid transporters. All transporters increased fatty acid transport, but FAT/CD36 and FATP4 were 2.3- and 1.7-fold more effective than FABPpm and FATP1, respectively. Fatty acid transporters failed to alter the rates of fatty acid esterification into triacylglycerols. In contrast, all transporters increased the rates of long chain fatty acid oxidation, but the effects of FABPpm and FAT/CD36 were 3-fold greater than for FATP1 and FATP4. Thus, fatty acid transporters exhibit different capacities for fatty acid transport and metabolism. In vivo, FAT/CD36 and FATP4 are the most effective fatty acid transporters, whereas FABPpm and FAT/CD36 are key for stimulating fatty acid oxidation.
Nickerson
James G
JG
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Alkhateeb
Hakam
H
Department of Laboratory Medical Sciences, Hashemite University, Zarqa 13115, Jordan.
Benton
Carley R
CR
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Lally
James
J
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Nickerson
Jennifer
J
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Han
Xiao-Xia
XX
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Wilson
Meredith H
MH
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Jain
Swati S
SS
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Snook
Laelie A
LA
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Glatz
Jan F C
JFC
Department of Molecular Genetics, Maastricht University, 6200 MD Maastricht, The Netherlands.
Chabowski
Adrian
A
Department of Physiology, Medical University of Bialystok, 15-222 Bialystok, Poland.
Luiken
Joost J F P
JJFP
Department of Molecular Genetics, Maastricht University, 6200 MD Maastricht, The Netherlands.
Bonen
Arend
A
From the Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada. Electronic address: abonen@uoguelph.ca.
D000818:Animals; D018955:CD36 Antigens / Q000235:genetics / Q000378:metabolism*; D050612:Fatty Acid Transport Proteins / Q000235:genetics / Q000378:metabolism*; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D015870:Gene Expression / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism*; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000378:metabolism
D018955:CD36 Antigens; C008132:Cd36 protein, rat; D050612:Fatty Acid Transport Proteins; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; C515999:Got2 protein, rat; C493570:Slc27a1 protein, rat; C542875:Slc27a4 protein, rat; D014280:Triglycerides