Alcohol and the liver: 1994 update

Area of Science:

• Hepatology
• Toxicology
• Gastroenterology

Background:

• Ethanol hepatotoxicity stems from alcohol dehydrogenase-induced nicotinamide adenine dinucleotide (NADH) and acetaldehyde generation.
• An inducible microsomal pathway also produces acetaldehyde, generating oxygen radicals and activating xenobiotics, increasing heavy drinkers' vulnerability to toxins.
• Factors like hepatitis C, cytokines, genetics, and age are increasingly recognized in disease development.

Purpose of the Study:

• To review current understanding of alcoholic liver disease (ALD) pathogenesis.
• To discuss emerging therapeutic strategies for ALD.
• To highlight the role of metabolic pathways, nutrient interactions, and host factors in ALD.

Main Methods:

• Literature review of current concepts in alcoholic liver disease.
• Analysis of ethanol metabolism pathways and their toxic byproducts.
• Examination of host factors and nutritional influences on ALD.

Main Results:

• Ethanol metabolism involves both alcohol dehydrogenase and a microsomal pathway, the latter producing oxygen radicals and activating xenobiotics.
• ALD pathogenesis is influenced by interactions with drugs, environmental toxins, hepatitis C, cytokines, genetics, sex, and age.
• Nutritional status, particularly deficiencies in glutathione, vitamin A, and beta-carotene, impacts ethanol toxicity and can be modulated by supplements like S-adenosyl-L-methionine and polyunsaturated lecithin.

Conclusions:

• Understanding ethanol's complex metabolic and toxicological pathways is crucial for ALD treatment.
• Emerging therapies focus on correcting metabolic imbalances and addressing nutritional deficits.
• Novel therapeutic agents like S-adenosyl-L-methionine and polyunsaturated lecithin show promise in preventing and treating ALD complications.