La Fountaine Michael F, Cirnigliaro Christopher M, Kirshblum Steven C, McKenna Cristin, Bauman William A
Department of Veterans Affairs Rehabilitation Research & Development Service National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters Veterans Affairs Medical Center, Bronx, New York, United States of America.
Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America.
PLoS One. 2017 Mar 27;12(3):e0173934. doi: 10.1371/journal.pone.0173934. eCollection 2017.
Interruption of sympathetic innervation to the liver and visceral adipose tissue (VAT) in animal models has been reported to reduce VAT lipolysis and hepatic secretion of very low density lipoprotein (VLDL) and concentrations of triglyceride-rich lipoprotein particles. Whether functional impairment of sympathetic nervous system (SNS) innervation to tissues of the abdominal cavity reduce circulating concentrations of triglyceride (TG) and VLDL particles (VLDL-P) was tested in men with spinal cord injury (SCI).
One hundred-three non-ambulatory men with SCI [55 subjects with neurologic injury at or proximal to the 4th thoracic vertebrae (↑T4); 48 subjects with SCI at or distal to the 5th thoracic vertebrae (↓T5)] and 53 able-bodied (AB) subjects were studied. Fasting blood samples were obtained for determination of TG, VLDL-P concentration by NMR spectroscopy, serum glucose by autoanalyzer, and plasma insulin by radioimmunoassay. VAT volume was determined by dual energy x-ray absorptiometry imaging with calculation by a validated proprietary software package.
Significant group main effects for TG and VLDL-P were present; post-hoc tests revealed that serum TG concentrations were significantly higher in ↓T5 group compared to AB and ↑T4 groups [150±9 vs. 101±8 (p<0.01) and 112±8 mg/dl (p<0.05), respectively]. VLDL-P concentration was significantly elevated in ↓T5 group compared to AB and ↑T4 groups [74±4 vs. 58±4 (p<0.05) and 55±4 μmol/l (p<0.05)]. VAT volume was significantly higher in both SCI groups than in the AB group, and HOMA-IR was higher and approached significance in the SCI groups compared to the AB group. A linear relationship between triglyceride rich lipoproteins (i.e., TG or Large VLDL-P) and VAT volume or HOMA-IR was significant only in the ↓T5 group.
Despite a similar VAT volume and insulin resistance in both SCI groups, the ↓T5 group had significantly higher serum TG and VLDL-P values than that observed in the ↑T4 and the AB control groups. Thus, level of injury is an important determinate of the concentration of circulating triglyceride rich lipoproteins, which may play a role in the genesis of cardiometabolic dysfunction.
据报道，在动物模型中，肝脏和内脏脂肪组织（VAT）的交感神经支配中断可减少VAT脂肪分解、极低密度脂蛋白（VLDL）的肝脏分泌以及富含甘油三酯脂蛋白颗粒的浓度。本研究在脊髓损伤（SCI）男性患者中测试了腹腔组织交感神经系统（SNS）神经支配功能障碍是否会降低甘油三酯（TG）和VLDL颗粒（VLDL-P）的循环浓度。
研究了103名非卧床SCI男性患者[55名第4胸椎或更高节段（↑T4）神经损伤患者；48名第5胸椎或更低节段（↓T5）SCI患者]以及53名健康对照（AB）受试者。采集空腹血样，通过核磁共振波谱法测定TG、VLDL-P浓度，通过自动分析仪测定血清葡萄糖，通过放射免疫分析法测定血浆胰岛素。通过双能X线吸收法成像并使用经过验证的专用软件包计算VAT体积。
TG和VLDL-P存在显著的组间主效应；事后检验显示，与AB组和↑T4组相比，↓T5组的血清TG浓度显著更高[分别为150±9 vs. 101±8（p<0.01）和vs. 112±8 mg/dl（p<0.05）]。与AB组和↑T4组相比，↓T5组的VLDL-P浓度显著升高[74±4 vs. 58±4（p<0.05）和55±4 μmol/l（p<0.05）]。两个SCI组的VAT体积均显著高于AB组，与AB组相比，SCI组的HOMA-IR更高且接近显著水平。仅在↓T5组中，富含甘油三酯的脂蛋白（即TG或大颗粒VLDL-P）与VAT体积或HOMA-IR之间存在显著的线性关系。
尽管两个SCI组的VAT体积和胰岛素抵抗相似，但↓T5组的血清TG和VLDL-P值显著高于↑T4组和AB对照组。因此，损伤水平是循环中富含甘油三酯脂蛋白浓度的重要决定因素，这可能在心脏代谢功能障碍的发生中起作用。
