ethanol catabolic process

Definition

Target type: biologicalprocess

The chemical reactions and pathways resulting in the breakdown of ethanol, CH3-CH2-OH, a colorless, water-miscible, flammable liquid produced by alcoholic fermentation. [GOC:ai, ISBN:0198506732]

Ethanol catabolism is a metabolic process that breaks down ethanol (ethyl alcohol) into less toxic compounds, primarily acetaldehyde and then acetate. This process occurs primarily in the liver, though some ethanol metabolism can also occur in other tissues. The breakdown of ethanol involves two main steps:

1. **Oxidation of Ethanol to Acetaldehyde:** This step is catalyzed by the enzyme alcohol dehydrogenase (ADH). ADH uses NAD+ (nicotinamide adenine dinucleotide) as a cofactor to oxidize ethanol, producing acetaldehyde and NADH (reduced form of NAD+). This step is the rate-limiting step in ethanol metabolism, meaning it determines the overall rate of ethanol breakdown.

2. **Oxidation of Acetaldehyde to Acetate:** Acetaldehyde, a toxic compound, is further oxidized by the enzyme aldehyde dehydrogenase (ALDH) to acetate. ALDH also uses NAD+ as a cofactor. Acetate is a less toxic compound and can be further metabolized or used for energy production.

The overall reaction can be summarized as follows:

Ethanol + NAD+ → Acetaldehyde + NADH + H+

Acetaldehyde + NAD+ + H2O → Acetate + NADH + H+

**Factors Affecting Ethanol Metabolism:**

* **Genetics:** Individual variations in the activity of ADH and ALDH enzymes can affect the rate of ethanol metabolism.
* **Gender:** Women generally have lower levels of ADH activity than men, which can lead to higher blood alcohol levels.
* **Nutrition:** A diet low in protein can reduce the activity of ADH and slow down ethanol metabolism.
* **Other factors:** The presence of other drugs or medications can also affect ethanol metabolism.

**Consequences of Ethanol Catabolism:**

* **Acetaldehyde Toxicity:** Acetaldehyde is a toxic compound that can cause a variety of adverse effects, including flushing, nausea, and headache.
* **NADH Accumulation:** The production of NADH during ethanol metabolism can disrupt other metabolic processes, such as gluconeogenesis (glucose production) and fatty acid oxidation.
* **Liver Damage:** Chronic ethanol consumption can lead to liver damage, including fatty liver, alcoholic hepatitis, and cirrhosis.

**Note:** Ethanol catabolism is a complex process that is influenced by a variety of factors. The information provided here is a simplified overview. For further details, please consult a professional medical source.'
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Proteins (5)

Compounds (23)