Department of Surgical Oncology, Gdynia Oncology Centre, PCK's Maritime Hospital in Gdynia, Gdynia, Poland.
Oncol Rep. 2012 Jul;28(1):319-23. doi: 10.3892/or.2012.1804. Epub 2012 May 4.
Cancer cachexia (CC), a progressive loss of body mass, is associated with decreased energy production. Abnormally low levels of L-carnitine (LC) in skeletal muscle means that mitochondrial β-oxidation of long-chain fatty acids (LCFA) does not occur efficiently in patients with CC. We assessed the influence of CC on LC distribution and the effects of parenteral lipid emulsions on plasma LC levels and urinary excretion. Fifty patients with CC were randomly assigned to total parenteral nutrition (TPN) with long-chain triglycerides (LCTs), or LCTs plus medium-chain triglycerides (MCTs) as 50/50. Patients were further separated into those with body-mass index (BMI) ≤ 19 kg/m(2) and BMI >19 kg/m(2). Plasma concentrations of total LC (TC) and free LC (FC) and their urinary excretion were measured, along with skeletal muscle LC levels. On average, plasma FC and TC were higher than reference values in all patients. Patients with BMI ≤ 19 kg/m(2) had lower plasma FC and TC than those with BMI >19 kg/m(2). Skeletal muscle FC in the BMI ≤ 19 kg/m(2) group was lower than reference value, but within the normal range in others. LC and FC urinary excretion was higher than reference values. Plasma LC and its urinary excretion were higher in patients administered pure LCTs relative to those given MCTs/LCTs. A decrease in skeletal muscle LC in cancer patients with CC (BMI ≤ 19 kg/m(2)) correlates with an increase in its plasma levels and increased renal excretion. A diet of MCTs/LCTs reduces LC release from muscle to plasma and urine more effectively than LCTs.
癌症恶病质（CC）是一种进行性的体重下降，与能量产生减少有关。骨骼肌中左旋肉碱（LC）水平异常降低意味着患有 CC 的患者线粒体β-氧化长链脂肪酸（LCFA）不能有效地进行。我们评估了 CC 对 LC 分布的影响以及肠外脂质乳剂对血浆 LC 水平和尿排泄的影响。50 名 CC 患者被随机分配到长链甘油三酯（LCTs）的全肠外营养（TPN）或 LCTs 加中链甘油三酯（MCTs）的 50/50。患者进一步分为体重指数（BMI）≤19 kg/m2 和 BMI＞19 kg/m2。测量了总 LC（TC）和游离 LC（FC）的血浆浓度及其尿排泄量，以及骨骼肌 LC 水平。平均而言，所有患者的血浆 FC 和 TC 均高于参考值。BMI≤19 kg/m2 的患者的血浆 FC 和 TC 低于 BMI＞19 kg/m2 的患者。BMI≤19 kg/m2 组的骨骼肌 FC 低于参考值，但在其他人中仍处于正常范围内。LC 和 FC 的尿排泄量高于参考值。与给予 MCTs/LCTs 的患者相比，给予纯 LCTs 的患者的血浆 LC 和 FC 尿排泄量更高。CC（BMI≤19 kg/m2）癌症患者骨骼肌 LC 减少与血浆水平升高和肾脏排泄增加有关。MCTs/LCTs 饮食比 LCTs 更有效地减少肌肉向血浆和尿液中 LC 的释放。
