Free radical scavenging by myocardial fatty acid binding protein.
Recent investigations have indicated the presence of a fatty acid binding protein (FABP) in mammalian heart. This protein binds free fatty acids and their esters with high affinity, however, its physiological role remains unknown. Since FABP constitutes a significant amount of cystolic protein, it is likely that it would be a target for free radical attack. To test this hypothesis, FABP was examined for scavenging against free radicals such as the superoxide anion (O2-), hydroxyl radical (OH.) and hypochlorite radical (OCl.) which may be present in an ischemic reperfused heart. Our results suggest that FABP scavenges O2-, OH. and OCl. as indicated by the FABP inhibition of O2- -dependent reduction of cytochrome c, OH.-dependent hydroxybenzoic acid formation and OCl.-mediated chemiluminescence response. FABP was found to be a more potent scavenger of these free radicals compared to bovine serum albumin. Furthermore, FABP was more effective in scavenging OH. than O2-, and inhibited OH. mediated lipid peroxidation process. These results indicate that FABP can scavenge free radicals which may be present in an ischemic/reperfused heart and, thus, may play a significant physiological role in the heart during ischemia and reperfusion.
Samanta
A
A
Department of Surgery, University of Connecticut School of Medicine, Farmington 06032.
Das
D K
DK
Jones
R
R
George
A
A
Prasad
M R
MR
D000418:Albumins / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism*; D005609:Free Radicals; D006878:Hydroxides / Q000378:metabolism; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid / Q000378:metabolism; D066298:In Vitro Techniques; D009206:Myocardium / Q000378:metabolism*; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D051381:Rats; D013481:Superoxides / Q000378:metabolism
D000418:Albumins; D002352:Carrier Proteins; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D005609:Free Radicals; D006878:Hydroxides; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D013481:Superoxides; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid