Intraluminal hydrogen peroxide induces a permeability change of the endoplasmic reticulum membrane.
Gulonolactone treatment of mice resulted in the elevation of hepatic ascorbate and hydrogen peroxide levels accompanied by transient liver swelling and reversible dilatation of endoplasmic reticulum cisternae. Although a decrease in glutathione (reduced form)/total glutathione ratio was observed in microsomes, the redox state of luminal foldases remained unchanged and the signs of endoplasmic reticulum stress were absent. Increased permeability of the microsomal membrane to various compounds of low molecular weight was substantiated. It is assumed that Gulonolactone-dependent luminal hydrogen peroxide formation in the endoplasmic reticulum provokes a temporary increase in non-selective membrane permeability, which results in the dilation of the organelle and in enhanced transmembrane fluxes of small molecules.
Margittai
Eva
E
Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University and MTA-SE Pathobiochemistry Research Group, PO Box 260, 1444 Budapest, Hungary.
Löw
Péter
P
Szarka
András
A
Csala
Miklós
M
Benedetti
Angelo
A
Bánhegyi
Gábor
G
D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010539:Permeability; D013400:Sugar Acids / Q000494:pharmacology*
D013400:Sugar Acids; C007895:gulonolactone; D006861:Hydrogen Peroxide; D005978:Glutathione; D001205:Ascorbic Acid