The total body mass of fatty acid ethyl esters in skeletal muscles following ethanol exposure greatly exceeds that found in the liver and the heart

Synthesis of fatty acid ethyl esters in mammalian tissues after ethanol exposure: a systematic review of the literature

The ability to undergo non-oxidative metabolism from ethanol to fatty acid ethyl esters (FAEEs) varies greatly among tissues and organs. To gain a greater understanding of non-oxidative ethanol metabolism to FAEE, we aimed to collect all published data on FAEE synthesis in mammalian organs and tissues to identify all tissues, organs, and enzymes that are known to, or likely possess FAEE-synthetic activity. A systematic search for relevant papers was performed and two independent reviewers examined potentially relevant abstracts (articles on FAEEs that pertain to ethanol exposure) to determine whether they met the inclusion criteria. Information on FAEE synthesis was retrieved from papers meeting the inclusion/exclusion criteria and summarized by organ/tissue/matrix examined. The systematic search through four databases yielded 78 articles that investigated FAEE synthesis by tissues, tissue fractions and cell lines, and 29 articles that attempted to purify and/or characterize the enzymes involved in FAEE synthesis. Two enzyme activities have been studied: FAEE synthase (FAEES, which conjugates ethanol and free fatty acid) and acyl-CoA: ethanol O-acyltransferase (AEAT, which conjugates ethanol and fatty acyl-CoA). Both activities are expressed by a variety of different enzymes. FAEES activity is the most widely studied and has been purified from several tissues and shown to be associated with several well-known enzymes, while the identity of enzymes possessing AEAT activity remains unknown. The organs and tissues that have been shown to synthesize FAEEs are discussed, with special emphasis on the studies that attempted to elucidate the enzymology of FAEE synthesis in those tissues.

Tissue-specific upregulation of HSP72 in mice following short-term administration of alcohol

Oxidative stress and cellular injury have been implicated in induction of HSP72 by alcohol. We investigated the association between HSP72 induction and oxidative stress in mouse tissues following short-term administration of high doses of alcohol and caffeine alone or in combination. Adult male C57BL/6J mice were gavaged with vehicle, alcohol (∼1.7 g/kg/day), caffeine (∼44 mg/kg/day), or alcohol plus caffeine once daily for ten consecutive days. Upon completion of the treatments, tissues were collected for structural and biochemical analyses. Alcohol alone caused mild to moderate lesions in heart, liver, and gastrocnemius muscle. Similar structural changes were observed following administration of alcohol and caffeine combined. Alcohol administration also led to decreased glutathione levels in all three tissues and reduced plasma superoxide dismutase capacity. In contrast, alcohol and caffeine in combination reduced glutathione levels only in liver and gastrocnemius muscle and had no effect on plasma superoxide dismutase. Significant elevations in HSP72 protein and mRNA and in HSF1 protein levels were noted only in liver by alcohol alone or in combination with caffeine. No significant changes in morphology and HSP72 were detected in any tissues tested following administration of caffeine alone. These results suggest that a redox mechanism is involved in the structural impairment caused by short-term high-dose alcohol. Oxidative tissue injury by alcohol may not be associated with tissue HSP72 induction. Induction of HSP72 in liver by alcohol is mediated at both the transcriptional and translational levels.

Laboratory models available to study alcohol-induced organ damage and immune variations: choosing the appropriate model

The morbidity and mortality resulting from alcohol-related diseases globally impose a substantive cost to society. To minimize the financial burden on society and improve the quality of life for individuals suffering from the ill effects of alcohol abuse, substantial research in the alcohol field is focused on understanding the mechanisms by which alcohol-related diseases develop and progress. Since ethical concerns and inherent difficulties limit the amount of alcohol abuse research that can be performed in humans, most studies are performed in laboratory animals. This article summarizes the various laboratory models of alcohol abuse that are currently available and are used to study the mechanisms by which alcohol abuse induces organ damage and immune defects. The strengths and weaknesses of each of the models are discussed. Integrated into the review are the presentations that were made in the symposium "Methods of Ethanol Application in Alcohol Model-How Long is Long Enough" at the joint 2008 Research Society on Alcoholism (RSA) and International Society for Biomedical Research on Alcoholism (ISBRA) meeting, Washington, DC, emphasizing the importance not only of selecting the most appropriate laboratory alcohol model to address the specific goals of a project but also of ensuring that the findings can be extrapolated to alcohol-induced diseases in humans.