Amyloid beta protein (25–35) stimulation of phospholipases A, C and D activities of LA‐N‐2 cells

FEBS Letters

Singh, Indrapal N.¹  Kanfer, Julian N.¹  McCartney, Douglas G.¹ 

[1] Department of Biochemistry and Molecular Biology, University of Manitoba, Winnipeg, Man., R3E 0W3, Canada

关键词: Amyloid beta protein;    Phospholipase A;    Phospholipase D;    Phospholipase C;    Receptor;    AβP;    amyloid beta protein;    PLA;    phospholipase A;    PLC;    phospholipase C;    PLD;    phospholipase D;    AD;    Alzheimer's disease;    PtdETOH;    phosphatidylethanol;    FFA;    free fatty acid;   

DOI  :  10.1016/0014-5793(95)00432-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

[³H]Myristic acid prelabeled LA-N-2 cells were exposed to varying concentrations of amyloid beta protein (25–35), from 20 to 250 μg/ml, and the activation of phospholipases A and D estimated. A progressive increase in phosphatidylethanol formation, a measure of phospholipase D activity, and of free fatty acid release, a measure of phospholipase A activity, was observed over a time-course of 60 min. [³H]Inositol prelabeled LA-N-2 cells were exposed to varying concentrations of AβP, from 20 to 125 μg/ml, and phospholipase C activation was measured. There was an increased release of inositol phosphates in the presence of amyloid beta protein as a function of incubation time. The effects of adrenergic, metabotropic amino acid and bombesin antagonists on the AβP mediated stimulation of phospholipase C activity was investigated. Propranolol, a β adrenergic antagonist, 7-chlorokynurenic acid, a metabotropic amino acid antagonist, and [Tyr⁴-d-Phe¹²]bombesin, a bombesin antagonist, blunted the AβP stimulation of phospholipase C activity in [³H]inositol prelabeled L-AN-2 cells. This suggests that amyloid beta protein activation of phospholipase C may be receptor mediated. The phospholipase C inhibitor U 71322 prevented the activation of phospholipase C by AβP. However, this activation was not effected by tocopherol, propylgallate, or vitamin C.

【 授权许可】

Unknown