Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
Department of Epidemiology, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis, IN, USA.
J Nutr. 2020 Aug 1;150(8):2156-2163. doi: 10.1093/jn/nxaa146.
Poor lifestyles have been linked to insulin insensitivity/hyperinsulinemia, which may contribute to downstream changes such as inflammation and oxidative damage and the development of chronic diseases. As a biomarker of intracellular oxidative stress, leukocyte mitochondrial DNA copy number (mtDNA-CN) has been related to lifestyle factors including diet and weight. No epidemiologic study has examined the relation between combined insulinemic potential of lifestyle and mtDNA-CN.
Our aim was to examine the association between Empirical Lifestyle Index for Hyperinsulinemia (ELIH) and leukocyte mtDNA-CN in US men and women.
This cross-sectional analysis included 2835 white adults without cancers, diabetes, or cardiovascular disease at blood collection, including 2160 women from the Nurses' Health Study and 675 men from the Health Professionals Follow-Up Study. ELIH is an index based on plasma C-peptide that characterizes the insulinemic potential of lifestyle (diet, body weight, and physical activity). Relative mtDNA-CN in peripheral blood leukocytes was measured by qPCR-based assay.
We found a significant inverse association between ELIH and mtDNA-CN. In multivariable-adjusted linear models, absolute least squares means ± SDs of mtDNA-CN z score across ELIH quintiles in women were as follows: Q1: 0.14 ± 0.05; Q2: 0.04 ± 0.06; Q3: 0.008 ± 0.05; Q4: 0.01 ± 0.05; and Q5: -0.06 ± 0.05 (P-trend = 0.006). Means ± SDs in men were as follows: Q1: 0.25 ± 0.09; Q2: 0.23 ± 0.09; Q3: 0.07 ± 0.09; Q4: 0.02 ± 0.09; and Q5: -0.04 ± 0.09 (P-trend = 0.007). Means ± SDs in all participants were as follows: Q1: 0.16 ± 0.05; Q2: 0.07 ± 0.05; Q3: 0.01 ± 0.05; Q4: 0.01 ± 0.05; and Q5: -0.05 ± 0.05 (P-trend = 0.0004).
Hyperinsulinemic lifestyles (i.e., higher ELIH) were associated with lower leukocyte mtDNA-CN among subjects without major diseases, suggesting that the difference in lifestyle insulinemic potential may be related to excessive oxidative stress damage.
不良生活方式与胰岛素不敏感/高胰岛素血症有关，后者可能导致下游炎症和氧化损伤等变化，并引发慢性疾病。白细胞线粒体 DNA 拷贝数（mtDNA-CN）作为细胞内氧化应激的生物标志物，与饮食和体重等生活方式因素有关。目前尚无流行病学研究探讨生活方式的胰岛素生成潜力与 mtDNA-CN 之间的关系。
我们旨在研究美国男性和女性中经验性高胰岛素血症生活方式指数（ELIH）与白细胞 mtDNA-CN 之间的关系。
本横断面研究纳入了 2835 名无癌症、糖尿病或心血管疾病的白人成年人，包括来自护士健康研究的 2160 名女性和来自健康专业人员随访研究的 675 名男性。ELIH 是一种基于血浆 C 肽的指数，可表征生活方式（饮食、体重和体力活动）的胰岛素生成潜力。通过基于 qPCR 的检测方法测量外周血白细胞中的相对 mtDNA-CN。
我们发现 ELIH 与 mtDNA-CN 呈显著负相关。在多变量调整的线性模型中，女性 ELIH 五分位数组中 mtDNA-CN z 分数的绝对最小二乘均数±SD 如下：Q1：0.14±0.05；Q2：0.04±0.06；Q3：0.008±0.05；Q4：0.01±0.05；和 Q5：-0.06±0.05（P 趋势=0.006）。男性的平均值±SD 如下：Q1：0.25±0.09；Q2：0.23±0.09；Q3：0.07±0.09；Q4：0.02±0.09；和 Q5：-0.04±0.09（P 趋势=0.007）。所有参与者的平均值±SD 如下：Q1：0.16±0.05；Q2：0.07±0.05；Q3：0.01±0.05；Q4：0.01±0.05；和 Q5：-0.05±0.05（P 趋势=0.0004）。
无重大疾病的受试者中，高胰岛素血症的生活方式（即较高的 ELIH）与白细胞 mtDNA-CN 较低有关，这表明生活方式胰岛素生成潜力的差异可能与过度氧化应激损伤有关。
