Characteristics of the myocardial PM-FABP: effect of diabetes mellitus.
Properties of the myocardial PM-FABP were studied in normal and STZ-diabetic rats. The fluorescent fatty acids trans-parinaric and cis-parinaric acids were used as analogs of straight-chain (saturated) and kinked-chain (unsaturated) fatty acids respectively. Parinaric acid binding was sensitive to trypsin. Trans-parinaric acid binding was more sensitive to this protease than the binding of cis-parinaric acid. Based on the difference in sensitivity of parinaric acid binding we believe that there are two separate binding sites associated with myocardial PM-FABP; one for unsaturated fats and the other for saturated fats. Diabetes enhanced both cis- and trans-parinaric acid binding capacity in cardiomyocytes; cis-parinaric acid by 2 fold and trans-parinaric acid by 2.6 fold. In addition, there was a concomitant accumulation of free fatty acids and triglycerides in the hearts of the diabetic animals. There was a 2.2 fold increase for fatty acids and a 1.6 fold increase for trigylcerides. This association between myocardial fatty acid build-up and enhanced myocardial PM-FABP during diabetes suggest that this carrier protein might have contributed to lipid accumulation in the hearts of the diabetic rats.
Heyliger
C E
CE
Division of Pharmaceutical Sciences, College of Pharmacy, University of Cincinnati Medical Center, OH 45167-0004, USA.
Scarim
A L
AL
Eymer
V P
VP
Skau
K A
KA
Powell
D M
DM
D000818:Animals; D009202:Cardiomyopathies / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005230:Fatty Acids, Nonesterified / Q000032:analysis; D005231:Fatty Acids, Unsaturated; D005456:Fluorescent Dyes; D006321:Heart / Q000187:drug effects; D008297:Male; D018996:Myelin P2 Protein / Q000378:metabolism*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D014280:Triglycerides / Q000032:analysis; D014357:Trypsin / Q000494:pharmacology
D002352:Carrier Proteins; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005230:Fatty Acids, Nonesterified; D005231:Fatty Acids, Unsaturated; D005456:Fluorescent Dyes; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D014280:Triglycerides; D013311:Streptozocin; D014357:Trypsin; C013641:parinaric acid