Yin 2014 J Clin Endocrinol Metab
| Yin X, Lanza IR, Swain JM, Sarr MG, Nair KS, Jensen MD (2013) Adipocyte Mitochondrial Function is Reduced in Human Obesity Independent of Fat Cell Size. J Clin Endocrinol Metab [Epub ahead of print]. |
Yin X, Lanza IR, Swain JM, Sarr MG, Nair KS, Jensen MD (2013) J Clin Endocrinol Metab
Abstract: It has been suggested that mitochondrial dysfunctional in adipocytes contribute to obesity-related metabolic complications. However, obesity results in adipocyte hypertrophy, large and small adipocytes from the same depot have different characteristics, raising the possibility that obesity-related mitochondrial defects are an inherent function of large adipocytes.Objective:to examine whether obesity, independent of fat cell size and fat depot, is associated with mitochondria dysfunction.Design:cross-sectional comparison.Setting:Academic medical center.Patients or Other Participants:omental (OM) and/or abdominal subcutaneous (SQ) adipose samples were collected from 20, age-matched obese and non-obese non-diabetic men and women undergoing either elective abdominal surgery or research needle biopsy.Intervention:None.Main Outcome Measures:mitochondrial DNA abundance, oxygen consumption rates (OCR) and citrate synthase (CS) activity from populations of large and small adipocytes (separated with differential floatation).Results:For both omental and subcutaneous adipocytes, at the cell and organelle level, OCR and CS activity were significantly reduced in cells from obese compared with non-obese volunteers, even when matched for cell size by comparing large adipocytes from non-obese and small adipocytes from obese. Adipocyte mitochondrial content was not significantly different between obese and non-obese volunteers. Mitochondrial function and content parameters were not different between small and large cells, omental and subcutaneous adipocytes from the same person.Conclusion:Adipocyte mitochondrial oxidative capacity is reduced in obese compared to non-obese adults and this difference is not due to cell size differences. Adipocyte mitochondrial dysfunction in obesity is therefore related to overall adiposity rather than adipocyte hypertrophy.
• O2k-Network Lab: US MN Rochester Nair KS
Labels: MiParea: Respiration, Comparative MiP;environmental MiP, Exercise physiology;nutrition;life style
Pathology: Obesity
Stress:Mitochondrial disease
Organism: Human
Tissue;cell: Fat
Preparation: Isolated mitochondria
Coupling state: OXPHOS
HRR: Oxygraph-2k
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