Search resultsIntracellular proteolytic systems in alcohol-induced tissue injury
Title
Intracellular proteolytic systems in alcohol-induced tissue injury
Publication type
Journal Article
Year of Publication
2003
Authors
Journal
Alcohol Research and Health
Volume
27
Issue
4
Pagination
317 - 324
Date published
2003
ISBN
0090838X (ISSN)
Keywords
alcohol, alcohol consumption, Alcohol dehydrogenases, alcohol liver disease, alcohol metabolism, Alcohol-Induced Disorders, Alcoholism, Animal, Animals, AODR (alcohol and other drug related) injury, apoptosis, Biochemical reaction property, brain cell, calpain, cell death, Cell Survival, cytochrome P450 2E1, cytolysis, enzymology, Ethanol metabolism, human, Humans, inflammation, injury, intracellular fluid, lysosome, metabolism, nonhuman, peptide hydrolase, Peptide Hydrolases, Protease inhibitors, proteasome, protein, protein degradation, protein function, protein hydrolysis, protein metabolism, Protein metabolism disorder, protein targeting, Proteolysis, review, Tissue, tissue injury, ubiquitin
Abstract
The body constantly produces proteins and degrades proteins that are no longer needed or are defective. The process of protein breakdown, called proteolysis, is essential to cell survival. Numerous proteolytic systems exist in mammalian cells, the most important of which are the lysosomes, the ubiquitin-proteasome pathway, and enzymes called calpains. Lysosomes are small cell components that contain specific enzymes (i.e., proteases) which break down proteins. Alcohol interferes with the formation and activity of lysosomes and thus may contribute to protein accumulation in the liver, which can have harmful effects on that organ. In the ubiquitin-proteasome pathway, proteins that are to be degraded are first marked by the addition of ubiquitin molecules and then broken down by large protein complexes called proteasomes. Alcohol impairs this proteolytic system through several mechanisms, possibly leading to inflammation and even cell death. Calpains are proteases that are involved in several physiological processes, including the breakdown of proteins that give cells their shape and stability. In contrast to the lysosomal and ubiquitin-proteasome systems, calpains in brain cells are activated by alcohol, to potentially detrimental effect.