Alcoholic myopathy and acetaldehyde.
Alcoholic myopathy is characterized by biochemical and morphological lesions within muscle, ranging from impairment of muscle strength and loss of lean tissue to cellular disturbances and altered gene expression. The chronic form of the disease is five times more common than cirrhosis and is characterized by selective atrophy of type 11 (anaerobic) fibres: type I (aerobic) fibres are relatively protected. Although the causative agent is known (i.e. ethanol), the intervening steps between alcohol ingestion and the development of symptoms and lesions are poorly understood. However, acetaldehyde appears to have an important role in the aetiology of the disease. For example, alcohol is a potent perturbant of muscle protein synthesis in vivo, and this effect is exacerbated by cyanamide pre-dosage, which raises acetaldehyde concentrations. Acetaldehyde alone also reduces muscle protein synthesis in vivo and proteolytic activity in vitro. The formation of acetaldehyde protein adducts is another mechanism of putative importance in alcoholic myopathy. These adducts are formed within muscle in response to either acute or chronic alcohol exposure and the adducts are located preferentially within the sarcolemmal and sub-sarcolemmal regions. However, the significance of protein adduct formation is unclear since we do not currently know the identity of the adducted muscle proteins nor whether adduction alters the biochemical or functional properties of skeletal muscle proteins.
Preedy
Victor R
VR
Nutritional Sciences Research Division, Department of Nutrition and Dietetics, The Franklin Wilkins Building, 150 Stamford Street, London SE 1 9NH, UK.
Crabb
David W
DW
Farrés
Jaume
J
Emery
Peter W
PW
D000079:Acetaldehyde / Q000378:metabolism*; D000426:Alcohol Dehydrogenase / Q000378:metabolism; D000429:Alcohol Oxidoreductases / Q000378:metabolism; D020751:Alcohol-Induced Disorders / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D002374:Catalase / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004195:Disease Models, Animal; D000431:Ethanol / Q000633:toxicity*; D006801:Humans; D009124:Muscle Proteins / Q000096:biosynthesis / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology; D009135:Muscular Diseases / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar
D009124:Muscle Proteins; D000431:Ethanol; D003577:Cytochrome P-450 Enzyme System; D000429:Alcohol Oxidoreductases; C092153:microsomal ethanol-oxidizing system; D000426:Alcohol Dehydrogenase; D002374:Catalase; D000079:Acetaldehyde