Peripheral fat loss and decline in adipogenesis in older humans.
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ABSTRACT: Objective
Aging is associated with a redistribution of body fat including a relative loss of subcutaneous peripheral fat. These changes in body fat can have important clinical consequences since they are linked to increased risk of metabolic complications. The causes and mechanisms of loss of peripheral fat associated with aging are not clear. The aim of this study was to assess whether defects in adipogenesis contribute to fat loss in aging humans, as suggested from animal studies, and to evaluate the role of inflammation on pathogenesis of fat loss.Materials/methods
Preadipocytes isolated from subcutaneous peripheral fat of healthy young and elderly subjects were compared in their ability to replicate and differentiate.Results
The results show that both the rate of replication and differentiation of preadipocytes are reduced in older subjects. The reduction in adipogenesis is accompanied by a higher plasma level of the inflammatory marker, soluble tumor necrosis factor receptor 2, and greater release of tumor necrosis factor ? from fat tissue.Conclusions
Thus, the gradual relative loss of peripheral fat in aging humans may in part result from a defect in adipogenesis, which may be linked to inflammation and increased release of proinflammatory cytokines from fat tissue.
SUBMITTER: Caso G
PROVIDER: S-EPMC3531563 | biostudies-literature | 2013 Mar
REPOSITORIES: biostudies-literature
Publications
Peripheral fat loss and decline in adipogenesis in older humans.
Caso Giuseppe G McNurlan Margaret A MA Mileva Izolda I Zemlyak Alla A Mynarcik Dennis C DC Gelato Marie C MC
Metabolism: clinical and experimental 20120919 3
<h4>Objective</h4>Aging is associated with a redistribution of body fat including a relative loss of subcutaneous peripheral fat. These changes in body fat can have important clinical consequences since they are linked to increased risk of metabolic complications. The causes and mechanisms of loss of peripheral fat associated with aging are not clear. The aim of this study was to assess whether defects in adipogenesis contribute to fat loss in aging humans, as suggested from animal studies, and ...[more]
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