Alcohol Metabolism Flashcards
ALT
alanine aminotransferase
alanine aminotransferase
converts alanine to pyruvate
AST
aspartate aminotransferase
Asparate aminotransferase
if high levels are found means liver damage
moderate alcohol consumption
1 drink/day for women
1-2 drinks/day for men
Beneficial factors to moderate alcohol consumption
Increased HDL cholesterol
decreased LDL cholesterol oxidation, blood clotting, platelet aggregation, homocysteine, cell aggregation
Detrimental factors from excessive alcohol consumption
Increased acetaldehyde, oxidative stress, triglycerides, cell aggregation, active species
Decreased HDL cholesterol
Standard drink sizes
12 oz beer, 8 oz Malt liquor, 5 oz wine, 1.5 oz liquor
Excessive alcohol includes:
- Binge drinking - women 4+ drinks, men 5+ drinks consumed at one occasion
- Heavy Drinking - W 8+ drinks/week, men 15+ drinks/week
How is ethanol metabolized?
Mainly by Alcohol Dehydrogenase (ADH) enzymes in the cytosol of the liver
what is the product of alcohol metabolism?
toxic acetaldehyde
ALDH
Acetaldehyde dehydrogenase
acetaldehyde dehydrogenase
an enzyme in the liver that converts acetaldehyde to acetic acid in alcohol metabolism
ALDH converts what, where, into what
Converts toxic acetaldehyde in the mitochondria to non-toxic acetate, which can be used by the muscle and other tissues as fuel
What can non-toxic acetate be converted into?
acetyl CoA
MEOS system full name and contribution
a.k.a. microsomal ethanol oxidizing system. part of the cytochrome P450 system of enzymes
MEOS system enzymes are embedded where and are what?
in the membrane of the ER and are inducible
The MEOS system is used when there are high or low levels of alcohol consumed?
High, free radicles are generated and it can interfere with drug metabolism
MEOS are what kind of enzymes
CYP (cytochrome P450)
What occurs due to binge drinking?
fat deposits will begin to develop
most drugs will cause what when taken during alcohol consumption
metabolism inhibition (ethanol induced)
if one takes 3x the suggested dose of Tylenol during alcohol consumption what will occur?
ethanol induced, acceleration of metabolism
Drinking excess amounts of alcohol involves what systems?
ADH and MEOS
oxidation of alcohol in liver cells causes what?
NADH/NAD+ ratio to rise
alcohol increases …
lipolysis
Lipolysis
breakdown of fat
__ ___ _____ is inhibited by the NADH in the liver causing what?
fatty acid oxidation, fat build up in the liver
excessive drinking causes an individual to produce more …
MEOS enzymes (increased gene expression)
alcohol effects on the frontal lobe 1
impairment of judgement
alcohol effects in the midbrain 2
speech and vision centres are impaired
alcohol effects in the cerebellum 3
hand-eye coordination and voluntary muscle function is impaired
alcohol effects in the medulla oblongata
heart and respiration affected, may pass out
alcohol induced hepatitis
when hepatocytes (liver cells) are damaged the transaminases (ALT + AST) are released into the bloodstream and are evidence of impaired liver function
in alcohol induced hepatitis how will ammonia and albumin levels be altered
ammonia will be elevated
albumin will be lowered
alcoholic hepatitis and fatty liver (steatosis) are
first steps in liver damage and are reversible
progression of liver damage will lead to …
fibrosis and ending in cirrhosis, non-reversible
responsibility of the liver
production of blood proteins (albumin), mineral-transporting proteins (transferrin), and proteins responsible for blood coagulation
acetaminophen
- normally tylenol is made more water soluble by other processes other than cytochrome P450
- this is good b/c that is made by cytochrome P450 pathway is toxic
- endogenous systems to detoxify small amounts generated
Bringing alcohol into acetaminophen pathway
- upregulating cytochrome P450
- leads to liver damage
- ethanol present you make more enzymes= more shuttled through minor pathway
When can fat deposits be seen on the liver?
after one episode of binge drinking
- destroy architecture of the liver and have problem detoxifying nitrogen
- can be reserved
what kind of agent is alcohol?
psychoagent
alcohol poisoning
unconscious, slow respirations (less than 8) and cold, clammy or bluish skin
alcohol is ingested and turned into what
acetaldehyde
where does beta oxidation occur?
inside mitochondria
NAD AND NADH effects
- once the extra NADH is there, the TCA cycle will slow down (no NAD to take electrons to ETC)
- nowhere for acetyl coA to go: can make ketones or fatty acids
When acetyl coA turns back into fatty acids what happens?
fat deposits in liver
hyperlipidemia
acetyl coA attaches to VLDL and goes out to bloodstream; sometimes it gets trapped and not go out
