Pratt V C, Watanabe S, Bruera E, Mackey J, Clandinin M T, Baracos V E, Field C J
Department of Agricultural, Food and Nutritional Sciences, University of Alberta, 410 Ag/Forestry Center, Edmonton, Alberta, T6G 2P5 Canada.
Br J Cancer. 2002 Dec 2;87(12):1370-8. doi: 10.1038/sj.bjc.6600659.
Metabolic demand and altered supply of essential nutrients is poorly characterised in patients with advanced cancer. A possible imbalance or deficiency of essential fatty acids is suggested by reported beneficial effects of fish oil supplementation. To assess fatty acid status (composition of plasma and neutrophil phospholipids) in advanced cancer patients before and after 14 days of supplementation (12+/-1 g day(-1)) with fish (eicosapentaenoic acid, and docosahexaenoic acid) or placebo (olive) oil. Blood was drawn from cancer patients experiencing weight loss of >5% body weight (n=23). Fatty acid composition of plasma phospholipids and the major phospholipid classes of isolated neutrophils were determined using gas liquid chromatography. At baseline, patients with advanced cancer exhibited low levels (<30% of normal values) of plasma phospholipids and constituent fatty acids and elevated 20 : 4 n-6 content in neutrophil phospholipids. High n-6/n-3 fatty acid ratios in neutrophil and plasma phospholipids were inversely related to body mass index. Fish oil supplementation raised eicosapentaenoic acid and docosahexaenoic acid content in plasma but not neutrophil phospholipids. 20 : 4 n-6 content was reduced in neutrophil PI following supplementation with fish oil. Change in body weight during the supplementation period related directly to increases in eicosapentaenoic acid in plasma. Advanced cancer patients have alterations in lipid metabolism potentially due to nutritional status and/or chemotherapy. Potential obstacles in fatty acid utilisation must be addressed in future trials aiming to improve outcomes using nutritional intervention with fish oils.
晚期癌症患者的代谢需求以及必需营养素供应的改变情况尚未得到充分描述。鱼油补充剂的有益作用提示了必需脂肪酸可能存在失衡或缺乏。为评估晚期癌症患者在补充14天（12±1克/天）鱼油（二十碳五烯酸和二十二碳六烯酸）或安慰剂（橄榄油）前后的脂肪酸状态（血浆和中性粒细胞磷脂的组成）。从体重减轻超过5%的癌症患者（n = 23）中采集血液。使用气相色谱法测定血浆磷脂和分离出的中性粒细胞主要磷脂类别的脂肪酸组成。基线时，晚期癌症患者血浆磷脂及其组成脂肪酸水平较低（<正常值的30%），中性粒细胞磷脂中20:4 n-6含量升高。中性粒细胞和血浆磷脂中高的n-6/n-3脂肪酸比值与体重指数呈负相关。补充鱼油可提高血浆中二十碳五烯酸和二十二碳六烯酸的含量，但不会提高中性粒细胞磷脂中的含量。补充鱼油后，中性粒细胞磷脂酰肌醇中的20:4 n-6含量降低。补充期间体重的变化与血浆中二十碳五烯酸的增加直接相关。晚期癌症患者可能由于营养状况和/或化疗而出现脂质代谢改变。在未来旨在通过鱼油营养干预改善预后的试验中，必须解决脂肪酸利用方面的潜在障碍。
