Fat Cell Size, Insulin Sensitivity, and Inflammation in Obese Children

Department of Mother and Child, Biology-Genetics, Section of Pediatrics, University of Verona, Verona, Italy.
The Journal of pediatrics (Impact Factor: 3.79). 12/2007; 151(6):647-52. DOI: 10.1016/j.jpeds.2007.04.053
Source: PubMed


To assess the association between adiposity indexes (body mass index [BMI], fat mass, adipocyte size) and circulating inflammation markers with known metabolic relevance or insulin sensitivity in overweight/obese children.
Twenty-eight children (males/females: 13/15) with different degrees of overweight (BMI z-score: 1.64-3.1; fat mass: 14.1-49.8 kg) were studied. BMI, body composition (dual-energy x-ray absorptiometry scanning), subcutaneous adipocyte diameter (needle biopsy of subcutaneous abdominal fat), blood tumor necrosis factor-alpha and interleukin-6 concentrations and insulin sensitivity (frequently sampled intravenous glucose tolerance test) were assessed.
Adipocyte diameter, more than BMI and fat mass, was significantly associated with interleukin-6 (r = 0.62, P < .001) and tumor necrosis factor-alpha (r = 0.61, P < .001). Moreover adipocyte size was associated with insulin sensitivity (R2 = 0.15, F = 4.69, P = .04) independently from fat mass.
Adipocyte size is a factor linked to both inflammation and insulin resistance in overweight/obese children. This is similar to the findings in adults and lends support to the tenet that the earlier obesity ensues, the more severe the biologic consequences may be.

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    • "In the later stages of terminal differentiation, proteins such as adipocyte-specific fatty acid–binding protein (aP2), adiponectin, and leptin are expressed (8). A fine balance between adipocyte hypertrophy and adipogenesis exists to prevent the formation of dysfunctional adipose tissue, since large cells are more likely to be insulin resistant (9,10) and therefore can influence adipose tissue metabolism. Despite significant progress over the last few years, additional genes and factors that influence adipogenesis, adipose tissue metabolism, and ultimately energy homeostasis still remain to be uncovered. "
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    Diabetes 09/2012; 62(1). DOI:10.2337/db12-0256 · 8.10 Impact Factor
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    • "Nevertheless, this association is not always observed [Mundi et al., 2010]. Inflammatory markers, which are thought to be the primary mediators of the pathological consequences of obesity, are also strongly correlated with adipocyte diameter in subcutaneous adipose tissue [Maffeis et al., 2007]. In middle-aged women, adipocyte size was reported to be a predictor of type 2 diabetes, independent from total body fat and distribution [Lonn et al., 2010]. "
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    Journal of Cellular Biochemistry 07/2011; 112(7):1773-86. DOI:10.1002/jcb.23098 · 3.26 Impact Factor
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    • "In adults, obesity is associated with increases in systemic inflammatory markers, as evidenced by studies documenting the association of BMI and visceral obesity with circulating levels of cytokines and acute-phase reactants [9] [10] [11]. In children, the presence of obesity also appears to be associated with increased levels of high-sensitivity CRP (hsCRP) [12], as well as other inflammatory mediators [13] [14] [15] [16] [17], that promote the development of endothelial and metabolic dysfunction [18] [19] [20] [21]. "
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    International Journal of Pediatrics 01/2010; 2010(1687-9740):846098. DOI:10.1155/2010/846098
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