Lipid Peroxidation Scavengers Prevent the Carbonylation of Cytoskeletal Brain Proteins Induced by Glutathione Depletion

Abstract

In this study, we investigated the possible link between lipid peroxidation (LPO) and the formation of protein carbonyls (PCOs) during depletion of brain glutathione (GSH). To this end, rat brain slices were incubated with the GSH depletor diethyl maleate (DEM) in the absence or presence of classical LPO scavengers: trolox, caffeic acid phenethyl ester (CAPE), and butylated hydroxytoluene (BHT). All three scavengers reduced DEM-induced lipid oxidation and protein carbonylation, suggesting that intermediates/products of the LPO pathway such as lipid hydroperoxides, 4-hydroxynonenal and/or malondialdehyde are involved in the process. Additional in vitro experiments revealed that, among these products, lipid hydroperoxides are most likely responsible for protein oxidation. Interestingly, BHT prevented the carbonylation of cytoskeletal proteins but not that of soluble proteins, suggesting the existence of different mechanisms of PCO formation during GSH depletion. In pull-down experiments, beta-actin and alpha/beta-tubulin were identified as major carbonylation targets during GSH depletion, although other cytoskeletal proteins such as neurofilament proteins and glial fibrillary acidic protein were also carbonylated. These findings may be important in the context of neurological disorders that exhibit decreased GSH levels and increased protein carbonylation such as Parkinson's disease, Alzheimer's disease, and multiple sclerosis.

Oxidative injury in multiple sclerosis cerebellar grey matter

“…Imbalances in the cellular redox homeostasis (increased ROS production alongside a lack in hydrogen peroxide detoxifying enzyme activity) may lead to an excess of hydrogen peroxide and the subsequent formation of 4-HNE and/or malondialdehyde as evident in this study. In support of this theory, in vitro studies have directly correlated decreased glutathione levels and GPX activity with increased lipid peroxidation and protein carbonylation (Bizzozero et al, 2006;Bizzozero et al, 2007). Our findings may therefore suggest that in MS the lack in activity of hydrogen peroxide detoxifying 11 enzymes during the inflammatory insult may conceivably play a pathogenic role in the accumulation of lipid peroxidation, oxidative stress and myelin injury in MS GM.…”

Direct reaction of taurine with malondialdehyde: evidence for taurine as a scavenger of reactive carbonyl species

“…25 Though MDA is frequently reported to react with amino compounds forming fluorescent products such as dihydropyridinium derivatives, 26-30 the contribution of MDA to protein carbonyls still remains controversial. 31 In our experimental conditions, MDA-modified BSA showed lipofuscinlike fluorescence at 460 nm when excited at 395 nm, which was consistent with the fluorescence of dihydropyridine. The results demonstrated that taurine inhibited the development of fluorescence of MDA and BSA adducts, which implied a preventive effect on the formation of AGEs/ALEs.…”

Amelioration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced behavioural dysfunction and oxidative stress by Pycnogenol in mouse model of Parkinson's disease

“…Extensive evidence exists that lipid and protein oxidations are important factors in normal aging and the pathogenesis of age-related neurodegenerative disorders such as PD (Bizzozero et al, 2007;Sánchez-Iglesias et al, 2007). Oxidative damage to lipids (producing LPO) and proteins (forming protein carbonyl) can lead to structural and functional disruption of the cell membrane and inactivation of enzymes, which finally leads to cell death (Avrova et al, 1998;Bavaresco et al, 2003).…”