O'Keefe S J, Ogden J, Dicker J
Nutrition Unit/Gastrointestinal Clinic, Groote Schuur Hospital, University of Cape Town, Observatory, South Africa.
JPEN J Parenter Enteral Nutr. 1987 Sep-Oct;11(5):447-53. doi: 10.1177/0148607187011005447.
The effects of branched chain amino acid (BCAA)-enriched diets (fed for 7 days) on encephalopathy, plasma amino acid concentrations, aromatic amino acid turnover, and protein synthesis rates were determined in eight patients with alcoholic liver failure. Four patients were given the diet intravenously (iv group) (total amino acids, 60-80 g/day, BCAA content 51%, energy 2000 kcal/day) and four patients (NG group) were given a semi-elemental formulation via constant nasogastric (NG) infusion (amino acids 58 g, BCAA 43%, oligopeptides 19.5 g, energy 2000 kcal/day). The enteral diet was given at one-half strength for the first 3 days. A 10-hr constant infusion of [U-14C]phenylalanine tracer was used in four patients to measure aromatic amino acid (AA) turnover and rates of incorporation into various body proteins. Seven of the eight patients made a good clinical recovery, with reversal of encephalopathy within 3 days of dietary intervention. One became septicemic and deteriorated. While plasma bilirubin concentrations dropped, liver enzymes remained elevated. Mean nitrogen balance was negative at the beginning and positive at the end of the study, in both groups. Initial amino acid profiles demonstrated low plasma BCAA content and BCAA:AA ratios. Significant improvements occurred in the iv group by day 2 and in both groups by day 7. Isotope studies showed that, whereas aromatic amino acid oxidation remained unchanged, greater quantities were incorporated in whole body protein, albumin, transferrin, fibrinogen, and immunoglobulins.
对8例酒精性肝衰竭患者测定了富含支链氨基酸(BCAA)的饮食(喂养7天)对脑病、血浆氨基酸浓度、芳香族氨基酸周转率和蛋白质合成率的影响。4例患者接受静脉内饮食(静脉组)(总氨基酸60 - 80克/天,BCAA含量51%,能量2000千卡/天),4例患者(鼻饲组)通过持续鼻胃管(NG)输注给予半要素制剂(氨基酸58克,BCAA 43%,寡肽19.5克,能量2000千卡/天)。肠内饮食在前3天以半量给予。4例患者使用[U - 14C]苯丙氨酸示踪剂进行10小时持续输注,以测量芳香族氨基酸(AA)周转率和掺入各种身体蛋白质的速率。8例患者中有7例临床恢复良好,在饮食干预后3天内脑病逆转。1例发生败血症并病情恶化。虽然血浆胆红素浓度下降,但肝酶仍保持升高。两组患者在研究开始时平均氮平衡为负,结束时为正。初始氨基酸谱显示血浆BCAA含量和BCAA:AA比值较低。静脉组在第2天、两组在第7天均有显著改善。同位素研究表明,虽然芳香族氨基酸氧化保持不变,但有更多的量掺入全身蛋白质、白蛋白、转铁蛋白、纤维蛋白原和免疫球蛋白中。