Rabini R A, Galassi R, Fumelli P, Dousset N, Solera M L, Valdiguie P, Curatola G, Ferretti G, Taus M, Mazzanti L
Department of Diabetology, INRCA Hospital, Ancona, Italy.
Diabetes. 1994 Jul;43(7):915-9. doi: 10.2337/diab.43.7.915.
A fraction from normal human plasma inhibiting Na(+)-K(+)-ATPase has been recently identified as lysophosphatidylcholine (LPC). The aim of this study was to investigate the existence of a relationship between the activity of the cellular membrane Na(+)-K(+)-ATPase and plasma LPC in human diabetes. We studied 10 patients with insulin-dependent-diabetes mellitus (IDDM), 14 patients with non-insulin-dependent diabetes mellitus (NIDDM), and 10 sex- and age-matched control subjects. Plasma LPC concentrations were increased in both IDDM and NIDDM patients compared with control subjects. Na(+)-K(+)-ATPase activity was reduced in both groups of patients in erythrocyte and platelet membranes. There was a significant correlation between the concentrations of plasma LPC and Na(+)-K(+)-ATPase activity in both erythrocyte and platelet membranes (P < 0.01). To investigate the effect of LPC on the enzyme, Na(+)-K(+)-ATPase activity was determined in erythrocyte membranes obtained from six healthy subjects after in vitro incubation with increasing concentrations of LPC (1-10 microM). Enzymatic activity was significantly reduced by in vitro LPC at a concentration of 2.5 microM, with a further decrease at 5 microM. These data suggest that the decrease in Na(+)-K(+)-ATPase activity in diabetes might be due to increased LPC concentrations.
最近，从正常人血浆中分离出一种抑制钠钾ATP酶的成分，即溶血磷脂酰胆碱（LPC）。本研究旨在探讨细胞膜钠钾ATP酶活性与人类糖尿病患者血浆LPC之间是否存在关联。我们研究了10例胰岛素依赖型糖尿病（IDDM）患者、14例非胰岛素依赖型糖尿病（NIDDM）患者以及10名年龄和性别相匹配的对照受试者。与对照受试者相比，IDDM和NIDDM患者的血浆LPC浓度均升高。两组患者红细胞和血小板膜中的钠钾ATP酶活性均降低。红细胞和血小板膜中血浆LPC浓度与钠钾ATP酶活性之间存在显著相关性（P < 0.01）。为研究LPC对该酶的影响，在体外将来自6名健康受试者的红细胞膜与浓度递增的LPC（1 - 10 microM）孵育后，测定钠钾ATP酶活性。体外LPC浓度为2.5 microM时，酶活性显著降低，5 microM时进一步下降。这些数据表明，糖尿病患者钠钾ATP酶活性降低可能是由于LPC浓度升高所致。
