Gastrointestinal Lecture 6 Part 2 Major Functions of the Liver

Question 1

The liver’s role in carbohydrate metabolism

Answer 1

Glycogen storage (synthesis and breakdown)
Gluconeogenesis (synthesis of glucose)
Blood glucose buffer function
takes up glucose post-prandially
Secretes glucose as needed

Question 2

The liver’s role in lipid metabolism

Answer 2

1. Storage (as Triglycerides [TG])
2. Beta-oxidation (energy production)
3. De novo lipogenesis (DNL)
4. Lipoprotein secretion

Question 3

emerging health problem

Answer 3

Non-alcoholic fatty liver disease (NAFLD), secondary to obesity, is an emerging health problem

Question 4

The liver’s role in detoxification

Answer 4

Hepatocytes express a suite of detoxifying enzymes from the cytochrome P450 family; “CYPs”

The general activity of CYPs is to detoxify xenobiotics and toxins, primarily through oxidation >>> the most common reaction catalyzed by CYPs is a mono-oxygenase reaction (incorporation of a hydroxyl group)

Question 5

CYPs are important contributors to ___________

Answer 5

drug metabolism

Question 6

livers role in detoxification of alcohol

Answer 6

Question 7

livers role in detoxification of Acetaminophen

Answer 7

Question 8

The liver’s role in detoxification: ammonia

Answer 8

Question 9

The liver’s role in detoxification: regeneration

Answer 9

The liver’s capacity for regeneration is remarkable

>>> Liver can regrow from as much as 25% of its original size

>>> Living donor liver transplantation (40-60% removal of donor liver)

has limits