Cantafora A, Masella R, Angelico M, Gandin C, Blount R J, Peterson S W
Istituto Superiore di Sanita, Laboratory of Metabolism, Rome.
Eur J Clin Invest. 1992 Dec;22(12):777-82. doi: 10.1111/j.1365-2362.1992.tb01446.x.
The aim of this study was to determine whether insulin receptor processing capabilities of human erythrocytes could be improved by changing the cell membrane lipid composition using an intravenous infusion of polyunsaturated phosphatidylcholine. Thirteen cirrhotics were submitted to the i.v. infusion of phosphatidylcholine (2 g day-1 for 3 days). Both erythrocyte lipid composition and insulin receptor processing ability were examined at the beginning of the study and at 0, 3 and 11 days after the end of the treatment. This treatment decreased the erythrocyte cholesterol to phospholipid molar ratio and increased the proportion of polyunsaturated fatty acids (mainly linoleic acid) immediately after the end of the treatment. The proportion of arachidonic acid increased immediately in the phosphatidylserine class and, a few days later, also in phosphatidylethanolamine. The phospholipid class distribution did not show any relevant modification in the course of the study. Surface insulin receptors, which generally were up-regulated in the untreated subject (-7.1 +/- 20.4%), showed an improvement in down regulation capabilities that appeared to be well correlated with the changes in lipid composition of cell membranes induced by i.v. infusion of polyunsaturated phosphatidylcholine. The confirmation of these findings also in target cells for insulin may open new perspectives in the treatment of diabetes mellitus.
本研究的目的是确定通过静脉输注多不饱和磷脂酰胆碱改变细胞膜脂质组成，是否能改善人红细胞的胰岛素受体加工能力。13名肝硬化患者接受了静脉输注磷脂酰胆碱（2克/天，共3天）。在研究开始时以及治疗结束后的0、3和11天，对红细胞脂质组成和胰岛素受体加工能力进行了检测。该治疗在治疗结束后立即降低了红细胞胆固醇与磷脂的摩尔比，并增加了多不饱和脂肪酸（主要是亚油酸）的比例。花生四烯酸的比例在磷脂酰丝氨酸类别中立即增加，几天后在磷脂酰乙醇胺中也增加。在研究过程中，磷脂类别分布未显示任何相关变化。表面胰岛素受体在未经治疗的受试者中通常上调（-7.1±20.4%），其下调能力有所改善，这似乎与静脉输注多不饱和磷脂酰胆碱引起的细胞膜脂质组成变化密切相关。在胰岛素靶细胞中也证实这些发现可能为糖尿病治疗开辟新的前景。
