Increased fatty acid uptake, a factor in increased hepatic triacylglycerol synthesis in aging rats.
The mechanisms responsible for the increased hepatic triacylglycerol synthesis in aging are not established. We studied [1-14C] palmitate uptake and its esterification to triacylglycerols in the isolated hepatocytes of 2-month, 10-month and 20-month-old normal rats. In all hepatocytes, palmitate uptake and its esterification were linearly related to medium palmitate concentration, but palmitate uptake and triacylglycerol synthesis by the hepatocytes of 10-month and 20-month-old rats were nearly double that observed with the cells of 2-month-old rats. These results suggest that increased fatty acid uptake by the liver cells was a contributory factor in the increased triacylglycerol synthesis observed in the liver of senescent rats. The changes in the hepatocyte leading to increased fatty acid uptake and hence increased triacylglycerol synthesis are detected as early as middle age of the rat.
D000375:Aging; D000818:Animals; D005227:Fatty Acids / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008297:Male; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000096:biosynthesis*
D005227:Fatty Acids; D010169:Palmitic Acids; D014280:Triglycerides; D019308:Palmitic Acid