Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.
Eur J Clin Invest. 2014 Jun;44(6):587-96. doi: 10.1111/eci.12275.
In several reports, C3 and C4 have been linked to diabetes and cardiovascular disease (CVD). Here, we investigate this link and the degree of C3 activation in elderly individuals.
In this study, C3 and C4 and the activation fragment C3a-desArg were analysed in 1016 subjects aged 70, in which blood pressure, lipid variables and fasting blood glucose were assessed.
C3 levels were related to all the investigated classical cardiovascular risk factors and the metabolic syndrome (BMI, waist circumference, fat distribution, blood pressure, blood glucose levels, TG) except total cholesterol and LDL cholesterol in a highly significant fashion (Spearman up to 0,5; P < 0·0001). C4 and C3a-desArg were associated in the same fashion but less significantly, while the ratios C4/C3 or C3a-desArg/C3 were not, indicating that the association was not directly related to complement activation. The levels C3 and to a lesser degree C4 and C3a-desArg were associated particularly with CRP, but also with E-selectin and ICAM-1. In addition, C3 and C4 levels were shown to decline significantly in 15 female subjects enrolled in a weight-reduction programme over 4 months.
A strong relation between C3, C4 and C3a-desArg levels, adipose tissue and risk factors of CVD was established. The data support that the adipose tissue produces complement components and generates initiators of inflammation, such as C3a and C5a, able to trigger a cyto/chemokine response, in proportion to the amount of adipose tissue. This corroborates the concept that complement contributes to the low-grade inflammation associated with obesity.
在几项报告中，C3 和 C4 与糖尿病和心血管疾病（CVD）有关。在这里，我们研究了这种联系以及老年人群中 C3 的激活程度。
在这项研究中，我们分析了 1016 名年龄在 70 岁的受试者的 C3 和 C4 以及无活性片段 C3a-desArg，其中评估了血压、血脂变量和空腹血糖。
C3 水平与所有调查的经典心血管危险因素和代谢综合征（BMI、腰围、脂肪分布、血压、血糖水平、TG）相关，但总胆固醇和 LDL 胆固醇除外，呈高度显著相关（Spearman 高达 0.5；P < 0.0001）。C4 和 C3a-desArg 以同样的方式相关，但不那么显著，而 C4/C3 或 C3a-desArg/C3 的比值则没有，这表明这种关联不是直接与补体激活有关。C3 和 C4 水平与 CRP 特别相关，与 E-选择素和 ICAM-1 也相关，但程度较低。此外，15 名参加体重减轻计划的女性受试者在 4 个月内 C3 和 C4 水平显著下降。
C3、C4 和 C3a-desArg 水平、脂肪组织和 CVD 危险因素之间建立了强烈的关系。这些数据支持脂肪组织产生补体成分并产生炎症的启动子，如 C3a 和 C5a，能够触发细胞因子/趋化因子反应，与脂肪组织的量成比例。这证实了补体有助于与肥胖相关的低度炎症的概念。
