Department of Psychiatry, New York University School of Medicine, 145 East 32nd St, New York, NY, 10016, USA.
Diabetol Metab Syndr. 2012 Jun 8;4(1):26. doi: 10.1186/1758-5996-4-26.
To ascertain whether the associations between obesity, inflammation, and insulin resistance established in human adult studies are found among adolescents.
We contrasted 36 obese and 24 lean youth on fasting glucose, insulin levels, lipid profile, hemoglobin A1C, markers of hepatic function, white blood cell count, C-reactive protein (CRP) and fibrinogen levels. The cytokines IL-6, TNF-α, IFN-γ, IL-10 and IL-4 and the adipokines leptin, resistin, and adiponectin were also compared between the two groups. The fasting glucose and insulin values were used to estimate the degree of insulin resistance with the homeostatic model assessment of insulin resistance (HOMA-IR). T-tests and correlations were run to examine group differences and associations between groups. In addition, regression analyses were used to ascertain whether the markers of inflammation were predictive of the degree of insulin resistance.
Although obese adolescents had clear evidence of insulin resistance, only CRP, fibrinogen and leptin were elevated; there were no group differences in pro- or anti-inflammatory cytokines nor adiponectin and resistin. Anthropometric measures of obesity and level of insulin resistance were highly correlated to the acute phase reactants CRP and fibrinogen; however, the degree of insulin resistance was not predicted by the pro- or anti-inflammatory cytokine markers. Obese adolescents had higher white blood cell counts. In addition they had higher circulating alanine aminotransferase concentrations and lower circulating albumin and total protein than lean adolescents, possibly as a result of hepatocyte damage from fatty liver.
Unlike rodent or adult studies, we found that wide-spread systemic inflammation is not necessarily associated with insulin resistance among adolescents. This finding does not support the current paradigm that the associations between obesity and insulin resistance are, to a significant degree, mediated by low grade systemic inflammation. These data support the need for further adolescent studies to explore these associations.
为了确定在人类成年研究中建立的肥胖、炎症和胰岛素抵抗之间的关联是否存在于青少年中。
我们对比了 36 名肥胖青少年和 24 名瘦青少年的空腹血糖、胰岛素水平、血脂谱、糖化血红蛋白、肝功能标志物、白细胞计数、C 反应蛋白（CRP）和纤维蛋白原水平。还比较了两组之间细胞因子 IL-6、TNF-α、IFN-γ、IL-10 和 IL-4 以及脂肪因子瘦素、抵抗素和脂联素的水平。使用稳态模型评估的胰岛素抵抗（HOMA-IR）来估计空腹血糖和胰岛素值来评估胰岛素抵抗的程度。进行 t 检验和相关性分析以检查组间差异和组间关联。此外，还进行了回归分析以确定炎症标志物是否可预测胰岛素抵抗的程度。
尽管肥胖青少年有明显的胰岛素抵抗证据，但只有 CRP、纤维蛋白原和瘦素升高；促炎或抗炎细胞因子以及脂联素和抵抗素在两组之间没有差异。肥胖的人体测量指标和胰岛素抵抗程度与急性期反应物 CRP 和纤维蛋白原高度相关；然而，促炎或抗炎细胞因子标志物并不能预测胰岛素抵抗的程度。肥胖青少年的白细胞计数较高。此外，他们的循环丙氨酸氨基转移酶浓度较高，而循环白蛋白和总蛋白较低，这可能是由于脂肪肝导致肝细胞损伤所致。
与啮齿动物或成人研究不同，我们发现广泛的系统性炎症不一定与青少年的胰岛素抵抗相关。这一发现不支持当前的观点，即肥胖与胰岛素抵抗之间的关联在很大程度上是由低度系统性炎症介导的。这些数据支持需要进一步进行青少年研究以探索这些关联。
