摘要
目的在不同糖耐量状态的肥胖人群中定量测定肝脏脂肪和骨骼肌脂肪的含量,评估胰岛素抵抗水平,探讨异位脂肪沉积与胰岛素抵抗的相关性。方法 26例研究对象根据体质量指数(BMI)和糖代谢情况分为糖耐量正常(NGT)-非肥胖组(10例)、NGT-肥胖组(9例)和糖耐量异常(IGT)-肥胖组(7例)。所有受试者均采用高胰岛素-正常葡萄糖钳夹试验评估胰岛素敏感性,磁共振质谱法(1HMRS)定量测定肝脏和骨骼肌脂肪含量,并进行人体参数测量及空腹血糖(FPG)、餐后2 h血糖(2 hPG)、空腹胰岛素、胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和糖化血红蛋白A1c等检测。采用线性相关及多元回归方法,分析胰岛素抵抗与异位脂肪沉积的相关性及主要相关因素。结果 IGT-肥胖组、NGT-肥胖组和NGT-非肥胖组葡萄糖输注率(GIR,M值)分别为3.95±1.66、6.14±1.90、8.78±2.46 mg/(kg·min),3组间存在显著性差异(P<0.05),IGT-肥胖组胰岛素敏感性最低。3组间肝脏脂肪含量亦存在显著性差异,分别为(15.23±3.09)%、(6.25±0.38)%、(1.89±0.90)%,P<0.05,IGT-肥胖组肝脏脂肪含量最高。3组胫骨前肌肌细胞内脂肪含量分别为1.54±0.66、2.69±0.95、2.61±1.45 mmol/kg,IGT-肥胖组和NGT-肥胖组较NGT-非肥胖组显著增高(P<0.05)。全研究组相关分析提示肝脏脂肪含量与M值呈显著负相关(r=-0.895,P<0.01)而与Homeostasis model assessment(HOMA)β存在正相关(r=0.708,P<0.01)。但胫骨前肌和比目鱼肌IMCL/肌细胞外脂肪含量与M值、HOMAβ均无显著相关性。多元回归分析显示,只有肝脏脂肪含量是胰岛素敏感性(M值)独立危险因素(Y=-30.562X+9.007,R^2=0.717,P<0.01)。结论肝脏脂肪含量而不是骨骼肌脂肪含量与胰岛素抵抗、糖代谢异常发生密切相关。
Objective To investigate the correlation between liver and skeletal muscle fat contents and insulin resistance in obese individuals with different levels of glucose tolerance. Methods Ten non-obese individuals with normal glucose tolerance(NGT), 9 obese individuals with NGT, and 7 obese individuals with impaired glucose tolerance(IGT) were enrolled in this study. All the participants were examined for insulin sensitivity by hyperinsulinemic-euglycemic clamp and for liver and skeletal muscle fat accumulation quantified by proton magnetic resonance spectroscopy(~1H MRS). The data were collected from the subjects including somatometric measurements, fasting plasma glucose, 2-h plasma glucose(2 hPG), fasting insulin,and blood biochemistry. Linear correlation analysis and multiple linear stepwise regression analysis were used to analyze the relationship between ectopic fat accumulation and insulin resistance. Results The glucose infusion rates(GIR, presented as the M value) differed significantly among IGT-obese(3.95±1.66 mg·kg^(-1)·min^(-1)), NGT-obese(6.14 ± 1.90 mg · kg^(-1)·min^(-1)) and NGTnon-obese(8.78 ± 2.46 mg · kg^(-1)·min^(-1)) groups(P<0.05). The 3 groups also showed significant differences in liver fat contents[(15.23±3.09)%,(6.25±0.38)%, and(1.89±0.90)%, respectively, P<0.05] and intramyocellular lipids in the tibialis anterior(2.69±0.95, 2.61 ± 1.45, and 1.54 ± 0.66 mmol/kg, respectively, P<0.05). Linear analysis revealed that liver fat content, but not skeletal muscle fat content, was significantly correlated with the M value. Multiple linear stepwise regression analysis using M value as the dependent variable(Y) revealed that liver fat content(X) was an independent factor inversely correlated with the M value(regression equation: Y=-30.562 X + 9.007, R^2=0.717, P<0.01).Conclusions Liver fat accumulation, but not skeletal muscle fat accumulation, is correlated with insulin resistance and impaired glucose metabolism.
出处
《南方医科大学学报》
CAS
CSCD
北大核心
2017年第11期1461-1466,共6页
Journal of Southern Medical University
关键词
异位脂肪沉积
胰岛素抵抗
高胰岛素-正常葡萄糖钳夹试验
磁共振质子谱
ectopic fat accumulation
insulin resistance
hyperinsulinemic-euglycemic clamp
proton magnetic resonance spectroscopy
