کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2487755 1114430 2007 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Methoxypolyethylene Glycol-block-polycaprolactone Diblock Copolymers Reduce P-glycoprotein Efflux in the Absence of a Membrane Fluidization Effect while Stimulating P-glycoprotein ATPase Activity
موضوعات مرتبط
علوم پزشکی و سلامت داروسازی، سم شناسی و علوم دارویی اکتشاف دارویی
پیش نمایش صفحه اول مقاله
Methoxypolyethylene Glycol-block-polycaprolactone Diblock Copolymers Reduce P-glycoprotein Efflux in the Absence of a Membrane Fluidization Effect while Stimulating P-glycoprotein ATPase Activity
چکیده انگلیسی
We have previously shown that amphiphilic diblock copolymers composed of methoxypolyethylene glycol-b-polycaprolactone (MePEG-b-PCL) increased the cellular accumulation and reduced the basolateral to apical flux of the P-glycoprotein substrate, rhodamine 123 (R-123) in caco-2 cells. The purpose of this study was to investigate membrane perturbation effects of MePEG-b-PCL diblock copolymers with erythrocyte membranes and caco-2 cells and the effect on P-gp ATPase activity. The diblock copolymer MePEG17-b-PCL5 induced increasing erythrocyte hemolysis at concentrations which correlated with increasing accumulation of R-123 into caco-2 cells. However, no increase in cellular accumulation of R-123 by non-P-gp expressing cells was observed, suggesting that diblock did not enhance the transmembrane passive diffusion of R-123, but that the accumulation enhancement effect of the diblock in caco-2 cells was likely mediated primarily via P-gp inhibition. Fluorescence anisotropy measurements of membrane fluidity and P-gp ATPase activity demonstrated that MePEG17-b-PCL5 decreased caco-2 membrane fluidity while stimulating ATPase activity approximately threefold at concentrations that maximally enhanced R-123 caco-2 accumulation. These results suggest that inhibition of P-gp efflux by MePEG17-b-PCL5 does not appear to be related to increases in membrane fluidity or through inhibition in P-gp ATPase activities, which are two commonly reported cellular effects for P-gp inhibition mediated by surfactants.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Pharmaceutical Sciences - Volume 96, Issue 4, April 2007, Pages 864-875
نویسندگان
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