Kaufman Christopher L, Kaiser Daniel R, Steinberger Julia, Kelly Aaron S, Dengel Donald R
School of Kinesiology, University of Minnesota, Minneapolis, MN 55102, USA.
Obesity (Silver Spring). 2007 May;15(5):1164-71. doi: 10.1038/oby.2007.619.
The objective was to examine cardiovascular autonomic (cANS) function and its potential relationships with leptin resistance, insulin resistance, oxidative stress, and inflammation in a pediatric sample with varying levels of obesity.
Participants were normal-weight (NW; BMI <85th percentile, 6 male, 4 female), overweight (OW; 85th percentile < BMI <95th percentile, 6 male, 4 female), and obese children (OB; BMI >95th percentile, 6 male, 10 female) who had cANS function assessed via heart rate variability (HRV) methods during resting conditions. Standard time-domain and frequency-domain measures [high-frequency normalized units (HFnu; measure of parasympathetic nervous system activity) and low frequency:high-frequency ratio (LF:HF; overall sympathovagal balance)] of HRV were calculated. Fasting blood samples were drawn for measurement of glucose, insulin, lipids, 8-isoprostane, leptin, soluble leptin-receptor (sOB-R), C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha). Results were reported as mean +/- standard error of the mean.
OB had significantly elevated LF:HF and decreased HFnu when compared with NW (p < 0.05), but no differences between OW and NW were observed. Measures of HRV were significantly related to leptin, insulin resistance, 8-isoprostane, and CRP (p < 0.05), but these relationships were not significant after adjustment for fat mass.
When compared with NW, OB but not OW children are characterized by cANS dysfunction and increased leptin, insulin resistance, oxidative stress, and inflammation (CRP). The relationships between these factors seem to be dependent on quantity of fat mass and/or other factors associated with being obese.
本研究旨在探讨不同肥胖程度的儿科样本中心血管自主神经（cANS）功能及其与瘦素抵抗、胰岛素抵抗、氧化应激和炎症之间的潜在关系。
研究对象为正常体重（NW；BMI<第85百分位数，男6例，女4例）、超重（OW；第85百分位数<BMI<第95百分位数，男6例，女4例）和肥胖儿童（OB；BMI>第95百分位数，男6例，女10例），在静息状态下通过心率变异性（HRV）方法评估其cANS功能。计算HRV的标准时域和频域指标[高频标准化单位（HFnu；副交感神经系统活动指标）和低频：高频比值（LF:HF；整体交感迷走神经平衡）]。采集空腹血样，检测血糖、胰岛素、血脂、8-异前列腺素、瘦素、可溶性瘦素受体（sOB-R）、C反应蛋白（CRP）、白细胞介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）。结果以平均值±平均标准误差表示。
与NW组相比，OB组的LF:HF显著升高，HFnu降低（p<0.05），但OW组与NW组之间未观察到差异。HRV指标与瘦素、胰岛素抵抗、8-异前列腺素和CRP显著相关（p<0.05），但在调整脂肪量后，这些关系不显著。
与NW组相比，OB组儿童而非OW组儿童具有cANS功能障碍，且瘦素、胰岛素抵抗、氧化应激和炎症（CRP）增加。这些因素之间的关系似乎取决于脂肪量和/或与肥胖相关的其他因素。
