Physiological compartmental analysis of alpha-linolenic acid metabolism in adult humans.
Physiological compartmental analysis of alpha-linolenic acid metabolism in adult humans.
复制标题
DOI：
--
复制
发表时间：
2001-08
影响因子：
6.5
通讯作者：
R. Pawlosky;J. Hibbeln;J. Novotny;N. Salem
中科院分区：
文献类型：
--
作者：
R. Pawlosky;J. Hibbeln;J. Novotny;N. Salem
根据8名健康受试者d5-18：3n-3、d5-20：5n-3、d5-22：5n-3和d5-22：6n-3的血药浓度-时间曲线，建立了α-亚麻酸代谢的生理房室模型。受试者口服1克剂量的α-亚麻酸同位素示踪剂(d5-18：3n-3乙酯)，同时严格控制以牛肉为基础的饮食。通过使用Windows模拟和分析建模程序，为每个受试者确定动力学参数。测定了n-3脂肪酸在血浆中的半衰期和平均通过时间。该模型预测n-3脂肪酸的血浆值与测量的稳态浓度很好地一致，并根据饮食的脂质分析确定的值预测每个受试者的饮食亚麻酸摄入量。只有约0.2%的血浆18：3N-3用于合成20：5N-3，大约63%的血浆20：5N-3可用于生产22：5N-3，以及37%的22：5N-3可用于合成22：6N-3。从18：3n-3到20：5n-3的转化效率低下，表明从α-亚麻酸合成长链n-3多不饱和脂肪酸在健康个体中是有限的。相反，从血浆20：5n-3到22：5n-3的质量转移速率要大得多，这表明饮食中的二十碳五烯酸可能很好地用于人体22：6n-3的生物合成。
A physiological compartmental model of alpha-linolenic acid metabolism was derived from the plasma concentration-time curves for d5-18:3n-3, d5-20:5n-3, d5-22:5n-3, and d5-22:6n-3 in eight healthy subjects. Subjects received a 1-g oral dose of an isotope tracer of alpha-linolenate (d5-18:3n-3 ethyl ester) while subsisting on a rigorously controlled beef-based diet. By utilizing the Windows Simulation and Analysis Modeling program, kinetic parameters were determined for each subject. Half-lives and mean transit times of the n-3 fatty acids in the plasma were also determined. The model predicted plasma values for the n-3 fatty acids in good accordance with the measured steady state concentrations and also predicted dietary linolenic acid intake for each subject in accordance with values determined by lipid analysis of the diet. Only about 0.2% of the plasma 18:3n-3 was destined for synthesis of 20:5n-3, approximately 63% of the plasma 20:5n-3 was accessible for production of 22:5n-3, and 37% of 22:5n-3 was available for synthesis of 22:6n-3. The inefficiency of the conversion of 18:3n-3 to 20:5n-3 indicates that the biosynthesis of long-chain n-3 PUFA from alpha-linolenic acid is limited in healthy individuals. In contrast, the much greater rate of transfer of mass from the plasma 20:5n-3 compartment to 22:5n-3 suggests that dietary eicosapentaenoic acid may be well utilized in the biosynthesis of 22:6n-3 in humans.