Correlation between the effect of the anti‐neoplastic ether lipid 1‐O‐octadecyl‐2‐O‐methyl‐glycero‐3‐phosphocholine on the membrane and the activity of protein kinase Cα

摘要: The antineoplastic ether phospholipid 1-O-octadecyl-2-O-methyl-sn-glycero-3-phophocholine (ET-18-OCH3) was incorporated into dimyristoylglycerophosphocholine (Myr2Gro-PCho)/dimyristoylglycerophosphoserine (Myr2Gro-PSer) (4 : 1 molar ratio) mixtures. Electron microscopy showed that the addition of ET-18-OCH3 reduced size vesicles. Small vesicles could be detected even at 60 mol% ET-18-OCH3. Sedimentation studies increasing presence phospholipids in supernatant, while turbidity measurements indicated a decrease absorbance as concentration increased. These findings may explained by formation small and/or mixed micelles. Infrared spectroscopy fluidity membrane considerably increased temperatures below phase transition, with only increase proportion gauche isomers after gel-to-fluid transition this sample. On other hand, protein kinase Cα (PKCα) activity progressively decreased when multilamellar vesicles, reaching minimum value 20 mol%, inhibition being attributed to modification produced cone-shaped molecule. At higher concentrations, however, activated enzyme maximum attained 50 mol%. This activation still concentrations once again inhibited, almost complete 80 mol%. When PKC assayed using large unilamellar slight observed very low concentrations.