|
|
||||||||
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, New York 10032
Submitted 3 June 2003 ; accepted in final form 13 November 2003
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.
triglyceride; adiponectin; leptin; glycerokinase and futile cycle; insulin sensitivity
This article has been cited by other articles:
![]() |
J. R. Miller, P. Siripurkpong, J. Hawes, A. Majdalawieh, H.-S. Ro, and R. S. McLeod The trans-10, cis-12 isomer of conjugated linoleic acid decreases adiponectin assembly by PPAR{gamma}-dependent and PPAR{gamma}-independent mechanisms J. Lipid Res., March 1, 2008; 49(3): 550 - 562. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. H. Koh, J.-Y. Park, H.-S. Park, M. J. Jeon, J. W. Ryu, M. Kim, S. Y. Kim, M.-S. Kim, S.-W. Kim, I. S. Park, et al. Essential Role of Mitochondrial Function in Adiponectin Synthesis in Adipocytes Diabetes, December 1, 2007; 56(12): 2973 - 2981. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Zhang, K. Guo, R. E. LeBlanc, D. Loh, G. J. Schwartz, and Y.-H. Yu Increasing Dietary Leucine Intake Reduces Diet-Induced Obesity and Improves Glucose and Cholesterol Metabolism in Mice via Multimechanisms Diabetes, June 1, 2007; 56(6): 1647 - 1654. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Chen, L. Liu, Y. Zhang, H. N. Ginsberg, and Y.-H. Yu Whole-body Insulin Resistance in the Absence of Obesity in FVB Mice With Overexpression of Dgat1 in Adipose Tissue Diabetes, December 1, 2005; 54(12): 3379 - 3386. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |