Response of individual serum free fatty acids to oral and intravenous glucose: relation to adipose tissue composition.
The rate of oral glucose delivery determines whether serum total free fatty acids remain low (glucose sipping over 210 min) or rebound 120-180 min after initial suppression (via glucose bolus), but the response of individual serum free fatty acids to glucose ingestion is largely unknown. In this study, we measured the changes over 240 min in the levels of individual serum free and esterified fatty acids after bolus or sipped glucose ingestion and determined the extent to which the changes are related to abdominal subcutaneous adipose tissue composition. In eight healthy volunteers, 74% of the prolonged suppression of total serum free fatty acids resulting from sipping 50 g glucose over 210 min was caused by a decrease in free linoleic and oleic acids, whereas 92% of the rebound in total free fatty acids 240 min after consuming 50 g of glucose as a bolus was caused by increases in free oleic and linoleic acids. Two hundred forty minutes after the oral glucose, slower intravenous clearance of 5 g glucose was directly correlated to higher total serum free fatty acids and free stearic acid and higher oleic but lower linoleic acid in adipose tissue. We conclude that the net response of serum free fatty acids to an oral glucose load is mediated primarily by oleic and linoleic acids in a manner largely unrelated to adipose tissue composition.
Cunnane
S C
SC
Department of Nutritional Sciences, Faculty of Medicine, St. Michael's Hospital, Toronto, Canada.
Jenkins
D J
DJ
Wolever
T M
TM
D000005:Abdomen; D000273:Adipose Tissue / Q000737:chemistry* / Q000187:drug effects; D000284:Administration, Oral; D000328:Adult; D000704:Analysis of Variance; D003124:Colorimetry; D005230:Fatty Acids, Nonesterified / Q000032:analysis / Q000097:blood*; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D012044:Regression Analysis; D013997:Time Factors
D005230:Fatty Acids, Nonesterified; D005947:Glucose