Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biochemistry Exam #2 > Clinical Application > Flashcards

Clinical Application Flashcards

(54 cards)

Start Studying
1
Q

What are the two disorders of fructose metabolism? Which is more severe?

A
  1. Fructokinase deficiency (essential fructosuria)

2. Aldose B deficiency (fructose poisoning) - more severe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the effect of fructokinase deficiency?

A

Fructose accumulation in the urine (fructose not broken down into fructose 1P)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the consequences of Aldose B deficiency?

A
  • Fructose 1P accumulates in the liver - Fructose 1P is osmotically active and leads to liver damage/failure when water is pulled into the liver
  • Decreased cellular Pi levels because it is not released since Fructose 1P is not broken down - this causes hypoglycemia because there is a decrease in liver glycogenolysis (no Pi to release Glucose 6P) AND decrease in ATP synthesis/gluconeogenesis (no Pi to make ATP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the recommended therapy for Aldose B deficiency?

A

Avoid dietary fructose and sucrose intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a disorder of galactose metabolism? Is this disorder considered benign or more severe?

A

Galactose 1P Uridyltransferase deficiency (classical galactosemia) is VERY severe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the consequences of Galactose 1P Uridyltransferase deficiency?

A
  • Galactose 1P accumulates in the liver - Galactose 1P is osmotically active and leads to liver damage/failure when water is pulled into the liver
  • Galactose accumulates in the blood (galactosemia) and urine (galactosuria)
  • Galactose in the cells (any type) is converted to galactitol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are two consequences of galactitol production?

A
  • Cataracts due to galactitol accumulation (galactitol leads to increased cellular osmolarity in the lens)
  • Kidney and nerve tissue damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the alternative name for Galactose 1P Uridyltransferase deficiency?

A

Classical galactosemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the alternative name for Fructokinase deficiency?

A

Essential fructosuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the alternative name for Aldose B deficiency?

A

Fructose poisoning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are Statin drugs? Do they work reversibly or irreversibly? What are they chemically similar to?

A

Stain drugs inhibit HMG CoA Reductase (inhibit second step of De Novo cholesterol synthesis)

  • Work as reversible competitive inhibitors
  • Chemically similar to HMG CoA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain the mechanism of Statin drugs (4 parts).

A
  • Inhibited HMG CoA Reductase activity
  • Increased LDL receptor synthesis (as a result of HMG CoA Reductase inhibition)
  • Increased LDL endocytosis
  • Decreased serum LDL-cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are bile acid sequestrants? What is an alternative name, and give an example of a bile acid sequestrant.

A

Bile acid sequestrants (aka resins) work as a charged resin which forms ionic bonds with bile acids - bile acids cannot then be recycled and must be excreted in the feces

Example of Resin: Cholestyramine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Explain the mechanism of bile acid sequestrant drugs (5 parts).

A
  • Decreased cytosolic cholesterol (cholesterol in the cell is used in De Novo cholesterol synthesis to produce bile acids)
  • Increased LDL receptor synthesis (as a result of HMG CoA Reductase inhibition)
  • Increased LDL endocytosis
  • Activated HMG CoA Reductase activity
  • Decreased serum LDL-cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are cholesterol absorption inhibitors and what do they result in? Give an example of a cholesterol absorption inhibitor.

A

Bind to a protein that is important to cholesterol absorption (located in the GI tract epithelium and hepatocytes)

Example of cholesterol absorption inhibitor: Ezetimbe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain the mechanism of cholesterol absorption inhibitor drugs (5 parts).

A
  • Decreased cytosolic cholesterol (cholesterol not absorbed)
  • Increased LDL receptor synthesis (as a result of HMG CoA Reductase inhibition)
  • Increased LDL endocytosis
  • Activated HMG CoA Reductase activity
  • Decreased serum LDL-cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Provide two examples of combination drug therapy.

A
  • Statins/Cholestyramine

- Statins/Ezetimbe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is there a deficiency of in Familial Hypercholesterolemia? What is the mechanism of this disorder?

A

Familial Hypercholesterolemia is a deficiency of the LDL receptor

  • Decreased LDL receptors means decreased LDL endocytosis resulting in increased serum LDL
  • Cytosolic cholesterol is also decreased resulting in increased HMG CoA Reductase activity and De Novo cholesterol synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the alternative name for Familial Hypercholesterolemia?

A

Type IIa Hyperlipidemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are three clinical presentations of Familial Hypercholesterolemia?

A
  • Xanthoma on extremities
  • Corneal arcus (grey/white ring around cornea)
  • Atherosclerosis (higher risk for cardiovascular disease)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the lipid profile for Familial Hypercholesterolemia look like?

A
  • High LDL cholesterol

- Normal TAGs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the recommended therapy for Familial Hypercholesterolemia?

Study These Flashcards
A

Reduction in dietary cholesterol and saturated fats; Combination drug therapy

23
Q

Why does cholelithiasis occur?

Study These Flashcards
A

Gallstones form as a result of abnormal bile composition (high free cholesterol and low bile acids)

24
Q

What are the five risk factors for cholelithiasis?

Study These Flashcards
A
  • Fat
  • Forty
  • Female
  • Fertile (high estrogen levels)
  • Fibrates (drugs that inhibit cholesterol 7-alpha-hydroxylase, which converts C to bile acids)
25
What is the solvent and solute in saturated solution? Why is this significant?
Cholesterol is the solute and bile acids are the solvent - Cholesterol is water insoluble and requires a solvent in supersaturated solutions in order to prevent crystal formation
26
What are the two treatment options for cholelithiasis and which is more common?
- Cholecystectomy (more common) | - Administration of exogenous ursodeoxycholic acid (medication) that supplements the body's supply of bile acids
27
What is there a deficiency of in Familial Chylomicronemia? What is the consequence of Familial Chylomicronemia?
Familial Chylomicronemia is a deficiency of LPL or Apo C-II TAGs in the CM are not hydrolyzed and remain in the CM (CMs are TAG-rich)
28
What does the lipid profile for Familial Chylomicronemia look like?
Elevated fasting CM (high TAGs) Top creamy layer with centrifugation
29
What are two clinical presentations of Familial Chylomicronemia?
- Xanthomata | - Pancreatitis (can be caused by high triglycerides)
30
Does Familial Chylomicronemia increase risk for heart disease?
NO
31
What are the two recommended treatments of Familial Chylomicronemia?
- Consume short- and medium-chain containing TAGs | - Fat-soluble vitamin supplementation
32
What is an alternative name for Familial Chylomicronemia?
Type I Hyperlipidemia
33
What is the cause of Abetalipoproteinemia? What is the consequence of Abetalipoproteinemia?
Loss of function in MTP gene (deficient MTP) TAGs are not transferred to nascent CMs or VLDLs (cannot be assembled)
34
What does the lipid profile for Abetalipoproteinemia look like?
CM, VLDL, and LDL are almost absent in plasma which leads to hypolipidemia
35
What are four clinical presentations of Abetalipoproteinemia?
- Failure to thrive - Dietary fat accumulation in enterocytes - Steatorrhea - Neurological defects due to malabsorption of fat-soluble vitamins
36
What are the two recommended treatments of Abetalipoproteinemia?
- Low-fat, calorie-rich diet | - Fat-soluble vitamin supplementation
37
What is an alternative name for Abetalipoproteinemia?
CM Retention disease
38
What is the cause of Familial Combined Hyperlipidemia Type IIb? What are the secondary causes? What is the consequence of Familial Combined Hyperlipidemia Type IIb?
Over production of Apo B-100 Secondary: obesity, metabolic syndrome, DM, HTN Excessive production of VLDLs
39
What does the lipid profile for Familial Combined Hyperlipidemia Type IIb look like?
- Elevated VLDLs (high TAGs) - Elevated LDLs (high CEs) - Decreased HDL
40
What is the increased risk associated with Familial Combined Hyperlipidemia Type IIb?
Higher risk for premature heart disease
41
What are the two recommended treatments of Familial Combined Hyperlipidemia Type IIb?
- Combined drug therapy (Niacin to reduce high TAGs and Statins or Resins to reduce high CEs) - Secondarily, diet and lifestyle changes
42
What is the cause of Familial Disbetalipoproteinemia Type III? What are the secondary causes? What is the consequence of Familial Disbetalipoproteinemia Type III?
Variation of Apo E protein (Apo E2 variant binds poorly to Apo E receptor) Secondary: high fat diet, DM, obesity, alcohol, hypothyroidism, estrogen deficiency There is decreased clearing of IDLs and CM remnants
43
What does the lipid profile for Familial Disbetalipoproteinemia Type III look like?
- Elevated IDLs | - Elevated CM remnants
44
What are four clinical presentations of Familial Disbetalipoproteinemia Type III?
- Tuboeruptive xanthomata - Palmar striated xanthomata - High risk for premature heart disease - High risk for peripheral vascular disease
45
What are the two recommended treatments of Familial Disbetalipoproteinemia Type III?
- Combined drug therapy (Niacin to reduce high TAGs and Statins or Resins to reduce high CEs) - Secondarily, diet and lifestyle changes
46
In individuals with increased CETP activity, does their lipid profile demonstrate elevated LDLs or HDLs? Is their risk for atherosclerosis increased or decreased?
LDLs because when CE is sent to the VLDLs from HDL, the HDL becomes unstable - risk for atherosclerosis is increased Lower CETP activity is preferred
47
What is there a deficiency of in Tangier disease? What are the three consequences of Tangier disease?
Tangier disease is a deficiency in ABCA1 protein - Deficient transport of cholesterol out of peripheral cells causing cholesterol accumulation in the tissues - Prevents HDL from maturing (no ABCA1 protein so cholesterol is not moved into HDL from peripheral tissues) - Impaired transfer of Apo C-II and Apo E
48
What does the lipid profile for Tangier disease look like?
- Low HDL | - Low LDL
49
What are four clinical presentations of Tangier disease?
- Enlarged, orange tonsils - Premature MI - Cornea clouding - Hepatosplenomegaly - Intermittent peripheral neuropathy due to CM accumulation
50
Is there a treatment for Tangier disease?
NO
51
What is an alternative name for Tangier disease?
alpha-lipoprotein deficiency
52
What are two drugs used to treat hyperTAG and to increase HDL?
Niacin and Fibrates
53
How does Niacin lower serum TAGs and increase serum HDL?
- Lower serum TAGs: niacin inhibits HSL and lipolysis therefore decreasing VLDL and LDL production - Increase serum HDL: niacin decreases the breakdown of Apo A-I, extending HDL half-life
54
How do Fibrates lower serum TAGs and increase serum HDL?
- Lower serum TAGs: fibrates activate LPL (more TAGs broken down and increase in VLDL clearance; also decreased secretion of nascent VLDLs) - Increase serum HDL: fibrates increase Apo A-I gene expression, producing more Apo A-I and ultimately HDLs

Biochemistry Exam #2 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions