Complex Lipids And Disorders

Question 1

Name 1 storage/simple lipid

Name 2 membrane/complex lipids

Answer 1

Triacylglycerols

Phospholipids and glycolipids

Question 2

Two sub sections of phospholipids

What is their difference

Answer 2

Glycerophospholipids and sphingolipids

One has glycerol backbone and other has sphingosine backbone

Question 3

Sub section of glycolipids

Answer 3

Sphingolipids

Question 4

What is difference between phospholipid sphingolipid and glycolipid sphingolipid?

Answer 4

Glycolipid one has a sugar attached; other one has PO4 and secondary alcohol (choline) attached

Question 5

1. Main role of phospholipids

2. Phospholipids serve as a component of what 3 things

Answer 5

1. Important in cell membrane for signaling and anchoring proteins etc.
2. Lipoprotein particles, pulmonary surfactants and bile

Question 6

What is the most important precursor for glycerophospholipids?

Answer 6

Phosphatidic acid (PA)

Question 7

What makes phospholipids different from each other?

Answer 7

All have PA, difference is in their secondary alcohol group

Question 8

*What is necessary in order to synthesize phospholipids

What is its function

Answer 8

CDP

Activates either the alcohol or DAG component - activates the head group (similar to how UDP was activator of glucose)

Question 9

Site of phospholipid synthesis?

Answer 9

Smooth ER

Question 10

1. What is lecithin
2. What is it important for
3. What will happen without it

Answer 10

1. A phospholipid
2. Making lung surfactant in infants
3. Atelectasis (lung collapse)

Question 11

How do you know when a baby lung is mature?

Answer 11

When lecithin/sphingomyelin ratio is greater than 2

Question 12

What do phospholipases do?

Name 2 phospholipases

Answer 12

Degrade glycerophospholipids

Phospholipase A2 and phospholipase C

Question 13

Phospholipase A2

1. Releases?
2. What part of body has a lot of this enzyme
3. What inhibits this enzyme?

Answer 13

1. Arachidonic acid
2. Pancreatic secretions
3. Glucocorticoids

Question 14

Phospholipase C

1. Found where in the body?
2. Activated by?

Answer 14

1. Liver lysosomes

2. PIP2 (secondary messenger signaling pathway)

Question 15

What is sphingomyelin

__ + __ = sphingomyelin

Answer 15

Phospholipid

Ceramide + phosphocholine group

Question 16

1. What is ceramide
2. Where is it synthesized
3. What is ceramide made from
4. So precursor for ceramide is

Answer 16

1. Precursor for glycosphingolipids
2. Cytosolic leaflet of ER
3. Palmitoyl-CoA + serine = sphinganine; fatty acyl CoA converts sphinganine to ceramide
4. Sphingosine and fatty acid

Question 17

Function of sphingomyelinase

What is it necessary for

Where is this enzyme located

Answer 17

Hydrolyzes sphingomyelin (brings it back to ceramide+phosphocholine)

Important for myelin sheath

Lysosome

Question 18

Niemann-Pick disease
1. Caused from deficiency in

2. Type A vs. Type B
3. Disease can be detected on slide by

Answer 18

1. Acid sphingomyelinase
2. Type A= more rare and more severe; death by age 2-3, enlarged liver and spleen due to lipid deposit
   Type B= less severe; can be treated with bone marrow/enzyme replacements
   ~both can also give mental retardation~
3. Zebra inclusion bodies

Question 19

Another name for glycolipids

Essential component of

Predominantly present on

Answer 19

Glycosphingolipids

All membranes (like phospholipids)

Nerve cells

Question 20

Glycolipids are antigenic what does that mean

Most important antigens for our purposes

Glycolipids also require?

Answer 20

Can have an antigen response, can cause inflammation

Blood types (A, B, AB, O) - determined by glycolipids

Ceramide

Question 21

What is the substrate for synthesis of glycolipids

Answer 21

Nucelotide sugar - usually UDP, could also be NANA (CMP-sialic acid)

Question 22

What is the difference between sphingophospholipid and sphingoglycolipid

Answer 22

Both have ceramide has hydrophobic tail but polar head will be different

Question 23

Glycolipids are degraded where ?

How?

Answer 23

Lysosome

Via endocytosis (acid glycosidases)

Question 24

What are the 4 classes of glycolipids

What makes them different

Glycolipids are important for

Answer 24

Cerebrosides, globosides, sulfatides, and gangliosides

What sugar is attached to the ceramide

Nerves/neurons/nervous system

Question 25

How to make each of the glycolipids: 1. Cerebrosides 2. Globosides 3. Sulfatides 4. Gangliosides

Answer 25

1. Ceramide +glucose (UDP) 2. Ceramide + 2 or more UDP 3. Ceramide + galactose 4. Ceramide + Globoside + *CMP-NANA*

Question 26

Cerebrosides are commin in

Answer 26

Myelin sheath, neurons, and maintaining integrity of skin

Question 27

Sulfatides are common in What is unique about these

Answer 27

Nerve and kidney These are the acidic glycolipids

Question 28

NANA is composed of NANA is synthesized from Reactivated by condensation with CTP to form

Answer 28

9 carbon sugar Hexose sugar and PEP CMP-sialic acid

Question 29

Other function of globoside/ganglioside

Answer 29

Shock absorbers of the skull

Question 30

Difference in blood type antigens 1. O 2. A 3. B

Answer 30

1. No galactose 2. Galactose amine 3. Galactose ~so difference depends on sugar that is attached to ceramide

Question 31

Sphingolipidoses function Deficiency leads to

Answer 31

Breakdown of sphingolipids in lysosome Progressive mental retardation and death in early childhood

Question 32

4 diseases of sphingolipidosis

Answer 32

Niemann pick, gauchers, tay-sachs, and fabry

Question 33

Niemann Pick * 1. Defect in 2. Symptoms 3. Leads to accumulation of 4. Key symptom

Answer 33

1. Sphingomyelinase 2. Liver/spleen enlargement, mental retardation 3. Sphingomyelin 4. Cherry red spot on macula of eye

Question 34

Tay-Sachs disease - common * 1. Defect in 2. Symptoms 3. Leads to accumulation of 4. Common in what kind of people

Answer 34

1. Beta Hexosaminidase A (Hex A) 2. Mental retardation, blindness, death by age 3. Ganglioside Gm2 4. Ashkenazi Jews ~also cherry red spot, but no organ involvement

Question 35

Gauchers disease - most common * 1. Defect in 2. Symptoms 3. Leads to accumulation of 4. How will cell appear on histology slide

Answer 35

1. Glucocerebrosidase 2. Liver/spleen enlargement, osteoporosis, mental retardation in infantile form only 3. Glucocerebroside 4. Cell looks like crumpled tissue paper

Question 36

Fabrys disease * 1. Defect in 2. Symptoms 3. Leads to accumulation of

Answer 36

1. Alpha galactosidase 2. Skin rash, kidney failure, pain in lower extremities 3. Trihexosylceramide