Clincal aspects of alcohol metabolism and oxidative stress

Question 1

What is the toxic metabolite in alcohol metabolism?

Answer 1

Actaldehyde

Question 2

What does prolonged and excessive alcohol consumption lead to (Acetaldehyde)

Answer 2

Acetaldehyde builds up, causing liver damage

Also excess NADH and Acetyl CoA causing changes in liver metabolism

Question 3

What three liver diseases can excessive alcohol intake lead to>

Answer 3

Fatty liver
Alcoholic hepatitis
Alcoholic cirrhosis

Question 4

What is the treatemtnfor alcohol dependence and how does it work?

Answer 4

Disulfiram
Inhibitor of aldehyde dehydrogenase
Causes acetaldehyde to build up quicker, so leads to the feeling of a hangover

Question 5

What does a Glucose 6 phosphate dehydrogenase deficiency lead to?

Answer 5

Limita amount of NADPH
This is required for the reduction of oxidised Glutathione (GSSG) to reduced glutathione (GSH)

Lower GSH means less protection to oxidative stress

Question 6

What is the clinical sign of Glucose 6P Dehydrogenase deficincy and explain how they are formed?

Answer 6

Heinz bodies
Dark staining in red blood cells due to precipitated hb
Hb forms cross links and aggregates

Question 7

Describe the process of cataracts formation in galactosemia

Answer 7

build up of galactose means that you have an increased activity of the alternative galactose breakdown pathway
This means increased activity of aldose reductase
converts NADPH–>NADP+
reduced protection from oxidative stress
Denatures the crystallin protein in the lens of the eye
denatured by inappropriate disulphide bond formation