Metabolism of Acylglycerols and Sphingolipids Flashcards Preview

EOM Test 4 > Metabolism of Acylglycerols and Sphingolipids > Flashcards

Flashcards in Metabolism of Acylglycerols and Sphingolipids Deck (22)
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1
Q

What are two possible fates for Fatty acids?

A

Incorporation into triacylglycerides for storage

Incorporation into phospholipid components of cells

2
Q

What is the beginning step for both fates of fatty acids?

A

Synthesis of Phosphatidate

3
Q

How is Phosphatidate synthesized?

A

Two acyl chains are attached to glycerol-3-phosphate

C1 is usually saturated

C2 is usually unsaturated

4
Q

How are triacyglycerides formed from phosphatidate?

A

Remove the phosphate

Add another FA chain

5
Q

What is the key regulator in glyceroneogenesis?

A

PEP carboxykinase

6
Q

How do glucocorticoids affect Type II diabetes?

A

Stimulate PEPCK in the liver to produce more triglycerides

Inhibit PEPCK in adipose tissues so newly synthesized triglycerides can’t be stored

Accumulation of FA in blood increases insulin resistance and disrupts the way muscles handle glucose

7
Q

What are Thiazolidinediones?

A

New drugs for treating Type II diabetes

Stimulates PEPCK in adipose tissue

8
Q

What are the four components of phospholipids?

A

Fatty Acid

Platform to attach FA - glycerol or sphingosine

Phosphate

Alcohol

9
Q

What are the four steps required for phospholipid synthesis?

A

Synthesis of a backbone

Attachment of FAs

Addition of hydrophilic head group through a phosphodiester bond

Alteration of the head group

10
Q

What is the role of CDP in phospholipid synthesis?

A

Required to activate either phosphatidate or the alcohol

11
Q

What is combined to synthesize a phospholipid?

A

Diacylglycerol and activated alcohol

Activated diacylglycerol and alcohol

12
Q

What is the most common phospholipid in mammals?

A

Phosphatidylcholine

13
Q

How is phosphatidylcholine formed?

A

Methylation of phosphatidylethanolamine

14
Q

How is phosphatidylserine formed?

A

Base exchange reaction with phosphatidylcholine or phosphatidylethanolamine

15
Q

How is ceramide formed?

A

Condensation of Palmitoyl CoA and Serine

Reduction with NADPH

Addition of Acyl group

Desaturation with FAD

16
Q

What polar head group is attached to sphingomyelin?

A

Phosphocholine

17
Q

What polar head group is attached to cerebroside?

A

Glucose

18
Q

How are sphingolipids degraded?

A

Internalized by endocytosis then fused with lysosomes

Deficiency in lyusosomal enzymes results in lipid degradation disease

19
Q

What is Type A Niemann-Pick?

A

Begins during infancy

Hepatosplenomegaly

Failure to thrive due to progressive deterioration of the nervous system

20
Q

What is Type B Niemann-Pick?

A

Less severe than Type A

21
Q

What is type C Niemann-Pick?

A

Not usually diagnosed until adulthood

22
Q

Describe Gaucher disease?

A

Macrophages become filled with undigested glucocerebroside

Spleen and liver enlarge

Fatigue, bleeding problems, fragile bones