肥胖儿童血清 CT、25-OHD 水平变化及其与胰岛素抵抗的关系

目的观察不同程度、类型肥胖儿童血清卡尼汀（CT）、25-羟基维生素D（25-OHD）水平，并分析其与胰岛素抵抗的关系。方法单纯性肥胖儿童60例（观察组，其中轻度肥胖23例，中度肥胖30例，重度肥胖7例；腹型37例，周围型33例），健康体检儿童30例（对照组）。采用高效液相色谱法测定两组血清CT水平，免疫化学发光法检测25-OHD水平，葡萄糖氧化酶法检测空腹血糖（FBG），放射免疫分析法检测空腹胰岛素（FINS）水平，ELISA法检测瘦素（LP）、脂联素（ADPN）水平，计算体质量指数（BMI）、腰臀比（WHR），按HOMA模型计算胰岛素抵抗指数（InRI），并分析观察组血清CT、25-OHD与其余观察指标的相关性。结果与对照组比较，观察组CT、25-OHD、ADPN水平降低，BMI、WHR、FBG、FINS、InRI、LP水平升高（P〈0．05或0．01）；与重度比较，观察组轻度、中度肥胖患儿血清CT、25-OHD水平升高（P均〈0．05）；与周围型比较，观察组腹型肥胖患儿血清CT、25-OHD水平降低（P均〈0．05）；观察组儿童血清CT与ADPN（r：0．364，P〈0．01）、25-OHD（r=0．251，P〈0．05）呈正相关，与WHR（r=0．351，P〈0．01）、FINS（r=0．270，P〈0．05）、InRI（r=0．395，P〈0．01）、IJP（r=0．273，P〈0．01）呈负相关。血清25-OHD与ADPN呈正相关（r=0．417，P〈0．01），与WHR（r=-0．435，P〈0．01）、InRI（r=-0．317，P〈0．01）、LP（r=-0．291，P〈0．01）呈负相关。结论不同类型及程度肥胖患儿血清CT、25-OHD水平不同，CT、25-OHD与肥胖儿童胰岛素抵抗有关。

Changes in levels of serum carnitine and 25-hydroxy vitamin D and their relationship with insulin resistance in children with obesity

Objective To investigate serum carnitine （CT） and 25-hydroxy vitamin D （25-OHD） levels and to ana- lyze their relationship with insulin resistance in children with different degrees and types of obesity. Methods Sixty chil- dren diagnosed with obesity were enrolled as the observation group （ including 23 cases of mild obesity, 30 cases of moder- ate obesity, 7 cases of severe obesity; abdominal type in 37 cases, peripheral type in 33 cases）, and 30 healthy children as control group. Serum levels of leptin （LP） and adiponectin （ADPN） were measured by enzyme linked immunosorbent as- say （ELISA） , serum CT levels were measured by high performance liquid chromatography, and serum levels of 25-OHD were measured by immunochemoassay. Fasting blood glucose （FBG） was detected by glucose oxidase method, and radio- immunoassay was used to detect the fasting insulin （FINS） level. Body mass index （BMI） and waist hip ratio （WHR） was calculated. Insulin resistance index （InRI） was calculated by homeostasis model assessment of insulin resistance （ HOMA- IR）. The relationship of serum CT and 25-OHD with the rest indexes was analyzed. Results Compared with the control group, the serum CT and 25-OHD levels and ADPN were significantly decreased, the indexes of BMI, WHR , FBG, FINS, InRI and LP were increased in the observation group （P 〈0.05 or P 〈0.01 ）. Serum levels of CT, 25-OHD in mild and moderate obesity groups were higher than those in severe obesity group （ all P 〈 0.05 ）. Serum levels of CT, 25-OHD in abdominal obesity group were lower than those in peripheral obesity group （ all P 〈 0.05 ）. The level of serum CT was positively correlated with serum ADPN （ r = 0. 364, P 〈 0. 01 ）, 25-OHD （ r = 0.251, P 〈 0. 05 ）, but negatively correlated with FINS （r =0.270,P〈0.05）, WHR（r=O. 351,P〈O. 01）, InRI （r =0.395,P〈0.01）, and LP（r =0.273,P 〈 0.01 ） in the observation group. The level of serum 25-OHD was positively correlated with ADPN （r = 0. 417 ,P 〈 O. 01 ）, but negatively correlated with WHR（r= -0.435,P〈0.01）, InRI （r = -0.317,P 〈0.01）, and LP（r = -0.291,P 〈 O. 01 ）. Conclusion Serum levels of CT and 25-OHD are intimately related to the degree and phenotype of obesity in children and the changes of CT and 25-OHD are associated with the insulin resistance of obese children.