title: Modifications of proteins by 4-hydroxy-2-nonenal in the ventilatory muscles of rats.
abstract: Although 4-hydroxy-2-nonenal (HNE, a product of lipid peroxidation) is a major cause of oxidative damage inside skeletal muscles, the exact proteins modified by HNE are unknown. We used two-dimensional electrophoresis, immunoblotting, and mass spectrometry to identify selective proteins targeted by HNE inside the diaphragm of rats under two conditions: severe sepsis [induced by E. coli lipopolysaccharides (LPS)] and during strenuous muscle contractions elicited by severe inspiratory resistive loading (IRL). Diaphragm HNE-protein adduct formation (detected with a polyclonal antibody) increased significantly after 1 and 3 h of LPS injection with a return to baseline values thereafter. Similarly, HNE-protein adduct formation inside the diaphragm rose significantly after 6 but not 3 h of IRL. Mass spectrometry analysis of HNE-modified proteins revealed enolase 3b, aldolase and triosephosphate isomerase 1, creatine kinase, carbonic anyhdrase III, aconitase 2, dihydrolipoamide dehydrogenase, and electron transfer flavoprotein-beta. Measurements of in vitro enolase activity in the presence of pure HNE revealed that HNE significantly attenuated enolase activity in a dose-dependent fashion, suggesting that HNE-derived modifications have inhibitory effects on enzyme activity. We conclude that lipid peroxidation products may inhibit muscle contractile performance through selective targeting of enzymes involved in glycolysis, energy production as well as CO(2) hydration.
authors.affiliation: Critical Care and Respiratory Divisions, Royal Victoria Hospital, McGill University Health Centre, McGill University, 687 Pine Avenue West, Montreal, Quebec H3A 1A1, Canada. sabah.hussain@muhc.mcgill.ca
authors.forename: Sabah N A
authors.initials: SN
authors.lastname: Hussain
authors.forename: Ghassan
authors.initials: G
authors.lastname: Matar
authors.forename: Esther
authors.initials: E
authors.lastname: Barreiro
authors.forename: Maria
authors.initials: M
authors.lastname: Florian
authors.forename: Maziar
authors.initials: M
authors.lastname: Divangahi
authors.forename: Theodoros
authors.initials: T
authors.lastname: Vassilakopoulos
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D004195:Disease Models, Animal; D015180:Electrophoresis, Gel, Two-Dimensional; D004798:Enzymes / Q000302:isolation & purification / Q000378:metabolism; D004926:Escherichia coli; D006131:Growth Inhibitors / Q000494:pharmacology; D015227:Lipid Peroxidation; D008070:Lipopolysaccharides / Q000633:toxicity; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012132:Respiratory Muscles / Q000166:cytology* / Q000187:drug effects; D018805:Sepsis / Q000473:pathology
chemical_list: D000447:Aldehydes; D004798:Enzymes; D006131:Growth Inhibitors; D008070:Lipopolysaccharides; C027576:4-hydroxy-2-nonenal