Peroxidation stimulated by lipid hydroperoxides on bovine retinal pigment epithelium mitochondria: Effect of cellular retinol-binding protein

• Published in: The international journal of biochemistry & cell biology Vol. 35; no. 7; pp. 1071 - 1084
• Main Authors: Terrasa, Ana M., Guajardo, Margarita H., Catalá, Angel
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.07.2003
• Subjects: Animals; arachidonic acid; Cattle; Cellular retinol-binding protein; chemiluminescence; cytosol; docosahexaenoic acid; epithelium; fatty acid composition; Fatty acid hydroperoxide; hydroperoxides; linoleic acid; Lipid peroxidation; Lipid Peroxidation - drug effects; Lipid Peroxides - pharmacology; mitochondria; Mitochondria - drug effects; Mitochondria - metabolism; mitochondrial membrane; Pigment Epithelium of Eye - drug effects; Pigment Epithelium of Eye - metabolism; Retinal pigment epithelium; retinol-binding protein; Retinol-Binding Proteins - metabolism; Retinol-Binding Proteins, Cellular; CRBP; PUFA; RPE; Lipid peroxidation; AHP; FABP; Cellular retinol-binding protein; DHP; Retinal pigment epithelium; SDS-PAGE; Fatty acid hydroperoxide; LHP; LOOH
• ISSN: 1357-2725; 1878-5875
• DOI: 10.1016/S1357-2725(02)00346-1

This study analyzes the effect of cellular retinol-binding protein (CRBP), partially purified from retinal pigment epithelium (RPE) cytosol, on the non-enzymatic lipid peroxidation induced by fatty acid hydroperoxides of mitochondrial membranes isolated from bovine RPE. The effect of different amounts (50, 75 and 100 nmol) of linoleic acid hydroperoxide (LHP), arachidonic acid hydroperoxide (AHP) and docosahexaenoic acid hydroperoxide (DHP) on the lipid peroxidation of RPE mitochondria was studied; RPE mitochondria deprived of exogenously added hydroperoxide was utilized as control. The process was measured simultaneously by determining chemiluminescence as well as polyunsaturated fatty acid (PUFA) degradation of total lipids isolated from RPE mitochondria. The addition of hydroperoxides to RPE mitochondria produces a marked increase in light emission that was hydroperoxide concentration dependent. The highest value of activation was produced by LHP. The major difference in the fatty acid composition of total lipids isolated from native and peroxidized RPE mitochondria incubated with and without hydroperoxides was found in the docosahexaenoic acid content, this decreased 40.90±3.01% in the peroxidized group compared to native RPE mitochondria. The decrease was significantly high: 86.32±2.57% when the lipid peroxidation was stimulated by 100 nmol of LHP. Inhibition of lipid peroxidation (decrease of chemiluminescence) was observed with the addition of increasing amounts (100–600 μg) of CRBP to RPE mitochondria. The inhibitory effect reaches the highest values in the presence of LHP.