Protein malfunction in Metabolic Disorders

Question 1

What happens in Type 1 diabetes?

Answer 1

The body’s own immune system attacks its own insulin and pancreatic cells that manufacture it. (hygene theory)

Question 2

What is GCK in type 1 diabetes and on what chromosome?

Answer 2

An enzyme that is key to glucose metabolism and helps to modulate insulin secretion, chromosome 7

Question 3

What is the treatment fot type 1 diabetes?

Answer 3

Appropriate dose of daily insulin is used to contol the disease but not cure it

Question 4

What is insulin dependent diabetes mellitus locus 1 or IDDM1 and on what chromosome is it on?

Answer 4

Chromosome 6 and it has genes for antigens.

Question 5

Obesity: what is the % of body fat that counts as being obese?

Answer 5

Men 25%, Women 30%

Question 6

What is leptin?

Answer 6

Acts as a lipostat, a network of signals contribute to weight homeostasis

Question 7

Where is leptin produced, and what is it encoded by and on what chromosome?

Answer 7

Adipocytes and is encoded by the Ob gene on chromosome 7

Question 8

What is the regulation of satiety? Give in normal and inn disease

Answer 8

Normal: fat stores in adipocytes elevated—> leptin serum released to brain—-> saiety redulated, person doesnt eat
Disease: Disrupted regulation of satiety, therefore the individual eats more.

Question 9

What does disrupted regulation of satiety lead to?

Answer 9

It leads to energy overload —>nutrient overload not being used—>leads to formation of adipocytes are building more lipids stores

Question 10

What is insulin rseistance?

Answer 10

Body doesnt respond to insulin–> insulin allows glucos to be taken up by blood strean into different tissues.

Question 11

What does PPARalpha do in the liver and muscle cells?

Answer 11

• increase fat oxidation and fasting response in the liver
• increase fat oxidation in the muscles

Question 12

What does PPARgamma do in muscles, adipose tissue and blood?

Answer 12

• increase insulin action in muscles
• increase adipocyte differentiation and survival and increase fat uptake and storage in adipose tissue
• decrease lipid conc in the blood

Question 13

What does PPARdelta do in muscles and adipose tissues

Answer 13

• Increase fat oxidation and energy expenditure in both muscles and adipose tissue

Question 14

Wilson disease: what is it?

Answer 14

Autosomal recessive disorder of copper transport, resulting in copper accumulation and toxicity to the liver and brain. failure to release copper into bile

Question 15

What is te gene responsible for Wilson’s disease?

Answer 15

ATP7B

Question 16

What is the main cuase of HH (hereditary hemochromatosis)?

Answer 16

Increased amount of iron that the body absorbs from the gut. Excess iron can lead to cirrhosis in the liver or diabetes if pancreas is affected.

Question 17

What gene can cause HH if mutated?

Answer 17

HFE

Question 18

What are the 3 main characteristic of HH1?

Answer 18

1. chronic excessive intestinal absorption of diety iron
2. increased deposistion of iron in parenchymal cells
3. decreased iron in reticuloendotheilial stores

Question 19

What is HFE molecular function?

Answer 19

Iron sensing
Senses iron replete conditions, lots of iron in the blood
HFE interacts with TfR2,signalling complex, produces a signalling cascade allows production Hepcidin—> regulation of whole body iron homeostasis

Question 20

What happens to HFE function in disease conditions?

Answer 20

HFE mutated—>signalling complex is not formed—> there is a loss of signalling, lack of hepcidin induction—> loss of iron homeostasis—> leads to progressive iron loading