11 Questions
What is the role of Aldehyde Dehydrogenase in alcohol metabolism?
Metabolize toxic acetaldehyde to acetate
Which molecule is involved in increasing blood flow into the liver and depressing the central nervous system during alcohol metabolism?
Acetate
What is the main function of the cytochrome P450 isozymes in alcohol metabolism?
Responsible for alcohol metabolism in microsomes
Which enzyme is a minor pathway of alcohol oxidation and oxidizes ethanol in the presence of hydrogen peroxide?
Catalase
What molecule is metabolized to acetyl CoA, involved in lipid and cholesterol biosynthesis during alcohol metabolism?
Acetate
What is the principal enzyme responsible for the metabolism of alcohol in the liver?
Alcohol dehydrogenase (ADH)
What is the highly reactive and toxic byproduct produced during alcohol metabolism by the alcohol dehydrogenase enzyme?
Acetaldehyde
Which of the following statements is true about the effects of alcohol?
The effects of alcohol depend on the concentration of alcohol in the blood over time.
Which of the following enzymes is involved in the metabolism of alcohol in non-liver tissues, such as the brain?
Both cytochrome P450 and catalase
What is a potential consequence of chronic alcohol consumption and alcohol metabolism?
Increased tissue damage
Which of the following statements is true about alcohol dehydrogenase (ADH)?
ADH is present in the cytosol and has many different variants (isozymes).
Study Notes
Alcohol Metabolism
- The effects of alcohol depend on its concentration in the blood (blood alcohol concentration, BAC) over time.
- BAC is determined by the rates of alcohol absorption, distribution, metabolism, and excretion.
Sites of Alcohol Metabolism
- The liver is the primary site of alcohol metabolism.
- Non-liver tissues, such as the brain, also metabolize alcohol, but through different enzymes.
Enzymes Involved in Alcohol Metabolism
- Alcohol dehydrogenase (ADH) is the primary enzyme responsible for metabolizing alcohol in the liver.
- Aldehyde dehydrogenase (ALDH2) metabolizes acetaldehyde to acetate in the mitochondria.
- Cytochrome P450 isozymes, such as CYP2E1, 1A2, and 3A4, are involved in alcohol metabolism in microsomes.
- Catalase is a minor pathway for alcohol oxidation, requiring hydrogen peroxide (H2O2).
Metabolic Pathways
- ADH converts ethanol to acetaldehyde, producing NADH and potentially contributing to tissue damage.
- ALDH2 converts acetaldehyde to acetate, producing NADH and increasing blood flow to the liver.
- Acetate is further metabolized to acetyl CoA, involved in lipid and cholesterol biosynthesis.
- Cytochrome P450 isozymes, such as CYP2E1, convert ethanol to acetaldehyde, producing ROS and increasing the risk of tissue damage.
Consequences of Chronic Alcohol Consumption
- Chronic alcohol consumption is linked to several pathological consequences and tissue damage.
- The generation of acetaldehyde and ROS may contribute to tissue damage and the formation of damaging molecules.
Learn about the effects of alcohol on the body and the process of alcohol metabolism, primarily carried out in the liver by enzymes such as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH2). Understand how blood alcohol concentration (BAC) is influenced by absorption, distribution, metabolism, and excretion over time.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
