Diminished activities of fatty acid synthesis enzymes in insulin-resistant adipocytes from spontaneously obese rats
- PMID: 39025
- DOI: 10.1055/s-0028-1092753
Diminished activities of fatty acid synthesis enzymes in insulin-resistant adipocytes from spontaneously obese rats
Abstract
Acetyl coenzyme A carboxylase and fatty acid synthetase activities were studied to determine the biochemical basis of the markedly impaired capacity of fat cells from spontaneously obese, old rats to convert glucose to fatty acids relative to cells from lean, young rats. Michaelis constants for the substrates of both enzymes were similar in large and small adipocyte homogenates. In contrast, Vmax values were over 80% less in homogenates from large relative to small cells on a per cell basis. Long-term dialysis or the presence of albumin during the assays failed to restore the activities of these enzymes in homogenates of large fat cells. The combination of equal volumes of homogenates from the two cell types resulted in carboxylase and synthetase activities intermediate between activities found in the two homogenates alone. Therefore, the presence of endogenous allosteric inhibitors does not appear to account for the markedly blunted fatty acid synthesis enzyme activities in large fat cells. These results suggest that the fatty acid synthesis impairment, which is a primary defect in the insulin resistance of the large cells, is at least partly due to diminished cellular contents of acetyl coenzyme A carboxylase and fatty acid synthetase.
Similar articles
-
Regulation of fatty acid synthesis.Fed Proc. 1979 Nov;38(12):2617-21. Fed Proc. 1979. PMID: 40828
-
Increased insulin sensitivity and responsiveness of glucose metabolism in adipocytes from female versus male rats.J Clin Invest. 1985 Jul;76(1):109-16. doi: 10.1172/JCI111932. J Clin Invest. 1985. PMID: 3894416 Free PMC article.
-
Primary role of decreased fatty acid synthesis in insulin resistance of large rat adipocytes.Am J Physiol. 1978 Feb;234(2):E182-9. doi: 10.1152/ajpendo.1978.234.2.E182. Am J Physiol. 1978. PMID: 623294
-
Fatty acid synthesis and its regulation.Annu Rev Biochem. 1983;52:537-79. doi: 10.1146/annurev.bi.52.070183.002541. Annu Rev Biochem. 1983. PMID: 6137188 Review. No abstract available.
-
Inhibitors of fatty acid synthesis in prokaryotes and eukaryotes as anti-infective, anticancer and anti-obesity drugs.Future Med Chem. 2012 Jun;4(9):1113-51. doi: 10.4155/fmc.12.62. Future Med Chem. 2012. PMID: 22709254 Review.
Cited by
-
Rat adipocyte utilization of different substrates: effects of cell size and the control of lipogenesis.Lipids. 1982 Sep;17(9):626-33. doi: 10.1007/BF02535369. Lipids. 1982. PMID: 6755125
-
De novo lipogenesis in human fat and liver is linked to ChREBP-β and metabolic health.Nat Commun. 2013;4:1528. doi: 10.1038/ncomms2537. Nat Commun. 2013. PMID: 23443556 Free PMC article.
-
Adipocyte lipid synthesis coupled to neuronal control of thermogenic programming.Mol Metab. 2017 May 31;6(8):781-796. doi: 10.1016/j.molmet.2017.05.012. eCollection 2017 Aug. Mol Metab. 2017. PMID: 28752043 Free PMC article.
-
Novel insights into adipose tissue heterogeneity.Rev Endocr Metab Disord. 2022 Feb;23(1):5-12. doi: 10.1007/s11154-021-09703-8. Epub 2021 Dec 21. Rev Endocr Metab Disord. 2022. PMID: 34935088 Free PMC article. Review.
-
A major role of insulin in promoting obesity-associated adipose tissue inflammation.Mol Metab. 2015 May 1;4(7):507-18. doi: 10.1016/j.molmet.2015.04.003. eCollection 2015 Jul. Mol Metab. 2015. PMID: 26137438 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources