Detoxification of Ethanol

• Ethanol oxidised to ethanal in hepatocyte cytoplasm; using ethanol dehydrogenase, NAD accepts hydrogen released, forming reduced NAD
• Ethanal is further oxidised to ethanoate (acetate) in mitochondria; using ethanal dehydrogenase, releases hydrogen, forms reduced NAD, ethanoate product bonds with coenzyme A to form acetyl CoA
• NAD also oxidises fatty acids for respiration; if too much NAD is used, more fatty acids are converted to lipids and stored in liver cells; called ‘fatty liver’ and can result in cirrhosis, common in alcoholics

  A) Ethanal

  B) Ethanoic Acid

  C) Acetyl Coenzyme A

  D) 2H

  E) NAD

  F) reduced NAD

  G) 2H

  H) NAD

  I) reduced NAD

  
• Acetyl CoA enters Krebs cycle, and reduced NAD is re-oxidised in mitochondria in oxidative phosphorylation, which causes ATP synthesis