Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA.
Obesity (Silver Spring). 2010 Mar;18(3):598-603. doi: 10.1038/oby.2009.322. Epub 2009 Oct 1.
Several research studies in different populations indicate that inflammation may be the link between obesity and insulin resistance (IR). However, this relationship has not been adequately explored among African Americans, an ethnic group with disproportionately high rates of obesity and IR. In this study, we conducted a comparative study of the relationship among adiposity, inflammation, and IR in African Americans and West Africans, the ancestral source population for African Americans. The associations between obesity markers (BMI and waist-to-hip ratio (WHR)), inflammatory markers (high-sensitivity C-reactive protein (hsCRP), haptoglobin, interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha), and IR (homeostasis model assessment of insulin resistance (HOMA(IR))) were evaluated in 247 West Africans and 315 African Americans. In average, African Americans were heavier than the West Africans (by an average of 1.6 BMI units for women and 3 BMI units for men). Plasma hsCRP, haptoglobin, and IL-6 (but not TNF-alpha level) were higher in African Americans than in West Africans. In both populations, BMI was associated with markers of inflammation and with HOMA(IR), and these associations remained significant after adjusting for sex and age. However, the pattern of associations between measured inflammatory markers and IR was different between the two groups. In West Africans, hsCRP was the only inflammatory marker associated with IR. In contrast, hsCRP, haptoglobin, and IL-6 were all associated with IR in African Americans. Interestingly, none of the associations between markers of inflammation and IR remained significant after adjusting for BMI. This finding suggests that in African Americans, the relationship between inflammatory markers and IR is mediated by adiposity.
几项针对不同人群的研究表明，炎症可能是肥胖症和胰岛素抵抗（IR）之间的联系。然而，这种关系在非裔美国人中尚未得到充分探讨，非裔美国人是一个肥胖症和 IR 发病率极高的种族群体。在这项研究中，我们对非裔美国人和西非人（非裔美国人的祖先来源群体）之间的肥胖症、炎症和 IR 之间的关系进行了比较研究。在 247 名西非人和 315 名非裔美国人中，评估了肥胖标志物（BMI 和腰臀比（WHR））、炎症标志物（高敏 C 反应蛋白（hsCRP）、触珠蛋白、白细胞介素（IL）-6 和肿瘤坏死因子（TNF）-alpha）与 IR（胰岛素抵抗的稳态模型评估（HOMA（IR）））之间的关联。总体而言，非裔美国人比西非人更重（女性平均 BMI 增加 1.6 单位，男性增加 3 单位）。非裔美国人的血浆 hsCRP、触珠蛋白和 IL-6（但 TNF-alpha 水平除外）水平高于西非人。在这两个群体中，BMI 与炎症标志物和 HOMA（IR）相关，这些关联在调整性别和年龄后仍然显著。然而，在这两个群体中，测量的炎症标志物与 IR 之间的关联模式不同。在西非人中，hsCRP 是唯一与 IR 相关的炎症标志物。相比之下，hsCRP、触珠蛋白和 IL-6 均与非裔美国人的 IR 相关。有趣的是，在调整 BMI 后，炎症标志物与 IR 之间的关联没有一个仍然显著。这一发现表明，在非裔美国人中，炎症标志物与 IR 之间的关系是由肥胖引起的。
