Premium
Incubation of endothelial cells in a superoxide‐generating system: Impaired low‐density lipoprotein receptor‐mediated endocytosis
Author(s) -
Poumay Y.,
RonveauxDupal M.F.
Publication year - 1988
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041360211
Subject(s) - endocytosis , scavenger receptor , receptor mediated endocytosis , umbilical vein , oxidative stress , malondialdehyde , ldl receptor , low density lipoprotein , receptor , superoxide , chemistry , biochemistry , superoxide dismutase , microbiology and biotechnology , lipoprotein , biology , enzyme , cholesterol , in vitro
Endothelial cells (EC) of blood vessels are submitted to oxidative stress under various circumstances. These conditions may modify EC functions; therefore, in the present work we have studied the receptor‐mediated endocytosis of low‐density lipoproteins (LDL) and malondialdehyde‐modified LDL by the LDL receptor and the “scavenger” receptor, respectively, in cultured human umbilical vein EC after short (0‐120 minutes) incubations in a superoxide anion (O 2 − ) generating system. In both receptor‐mediated processes, the oxidative stress produces a significant decrease at four different LDL concentrations (5‐50 μg/ml) after 120 minutes of oxidation. On the other hand, the fluid‐phase endocytosis of sucrose by EC seems to be stimulated by these conditions. Furthermore, incorporation of antioxidant enzymes in the O 2 − −producing system shows that H 2 O 2 is an obligatory intermediate in order to produce the effect on the receptor‐mediated processes. Hypotheses concerning the mechanisms involved in the modifications of endocytotic processes and their implications in vivo are discussed.