Chronological changes in metabolism and functions of cultured adipocytes: a hypothesis for cell aging in mature adipocytes
Open Access
- 1 March 2004
- journal article
- Published by American Physiological Society in American Journal of Physiology-Endocrinology and Metabolism
- Vol. 286 (3) , E402-E410
- https://doi.org/10.1152/ajpendo.00247.2003
Abstract
The growth and aging of 3T3-L1 adipocytes were investigated in a synchronized tissue-culture system. We systematically characterized several major aspects of adipocyte metabolism and functions as variables of cell age. We found that terminal differentiation of 3T3-L1 cells is followed by a near-linear hypertrophic growth (increase in triglyceride content) of the cultured adipocytes throughout a 20-day study period. However, three metabolically and functionally distinct stages are recognized. The first stage overlaps with differentiation and is represented by small immature adipocytes. The second stage is characterized by fully mature adipocytes that show peaked overall metabolic activities. The third stage is marked by cell aging, with deterioration in every major aspect of the cell's functionality except for the function of net energy storage, which is preserved even in aged adipocytes. Compared with young mature adipocytes, older cells are increasingly insulin resistant, have decreased glucose uptake and fuel consumption, and show impaired glycerokinase-mediated fatty acid reesterification. Moreover, aged adipocytes show reduced gene expression for adiponectin and leptin, each of which is important in systemic regulation of energy metabolism. The characterization of these cell age-dependent changes in adipocyte functionality provides a model for understanding dynamic changes at the tissue level and suggests that adipose tissue is modifiable via adipocyte aging.Keywords
This publication has 54 references indexed in Scilit:
- Adipose tissue cellularity and apoptosis after intracerebroventricular injections of leptin and 21 days of recovery in ratsInternational Journal of Obesity, 2003
- Posttranscriptional Control of the Expression and Function of Diacylglycerol Acyltransferase-1 in Mouse AdipocytesPublished by Elsevier ,2002
- Inhibition of cAMP-response Element-binding Protein Activity Decreases Protein Kinase B/Akt Expression in 3T3-L1 Adipocytes and Induces ApoptosisPublished by Elsevier ,2002
- TNFα Induces and Insulin Inhibits Caspase 3-Dependent Adipocyte ApoptosisBiochemical and Biophysical Research Communications, 2001
- Mycobacterium bovis Bacillus Calmette-Guerin and Its Cell Wall Complex Induce a Novel Lysosomal Membrane Protein, SIMPLE, That Bridges the Missing Link between Lipopolysaccharide and p53-inducible Gene, LITAF(PIG7), and Estrogen-inducible Gene, EET-1Journal of Biological Chemistry, 2001
- Suppression of Preadipocyte Differentiation and Promotion of Adipocyte Death by HIV Protease InhibitorsJournal of Biological Chemistry, 2000
- Molecular Regulation of AdipogenesisAnnual Review of Cell and Developmental Biology, 2000
- Human Adipocyte Apoptosis Occurs in MalignancyBiochemical and Biophysical Research Communications, 1994
- Effect of Insulin on Lipolysis in Adipose Tissue of Rats of Different AgesHormone and Metabolic Research, 1986
- Glycerokinase activity and lipolysis regulation in brown adipose tissue of cold acclimated ratsBiochimie, 1976