Omega-3 FAs

Question 1

_____ gives rise to the “n-6 series” of PUFAs such as arachidonic

Answer 1

linoleic

Question 2

alpha-linolenic gives rise to the “n-3 series” PUFAs such as ___ and ____

Answer 2

EPA; DHA

Question 3

____ acid gives rise to the “n-9 series” of FAs, such as nervonic (24:1, n-9)

Answer 3

Oleic

Question 4

Utlization of alpha-linolenic acid to synthesize EPA and DHA is ____ in humans

Answer 4

limited

Question 5

____ may be utilized by COX and lipoxygenase to form prostaglandins and thrombaxanes of the “3” series, and leukotrienes of the “5” series

Answer 5

EPA

Question 6

DHA and EPA may be used to synthesize lipid mediators called resolvins and protectins. What do these compounds do?

Answer 6

resolve actue inflammation

note: appear to be important in brain

Question 7

DHA is known to be important in the normal ___ and ___ development

Answer 7

visual; neurological

Question 8

In regards to dietary sources of essential FAs, where is Linoleic acid found?

Answer 8

veg. oils

Question 9

In regards to dietary sources of essential FAs, where is alpha-linolenic acid found?

Answer 9

plant based oils (walnut, soy, canola)

Question 10

In regards to dietary sources of essential FAs, where are EPA and DHA found?

Answer 10

fish (cold water, fatty, large fish)

note: synthesized by cold water plants and are concentrated in the fish

Question 11

Decreased levels of n-3 PUFAs are associated with increased ____ ____ events

Answer 11

cardiovascular disease

note: n-3 PUFAs consumption is good!

Question 12

Anti-Arrhythmic is a reason by which n-3 PUFAs could decrease risk of cardiovascular disease. Explain the proposed mechanism.

Answer 12

modification of membrane phospholipids with the n-3 PUFAs, in turn, modifying the electrophysiology of the cardiac muscle

Question 13

Decreases platelet aggregation is a reason by which n-3 PUFAs could decrease risk of cardiovascular disease. Explain the proposed mechanism.

Answer 13

1. EPA competes with arachidonic acid for cyclooxygenase
2. products from cyclooxyrgenase from EPA include PGI2 and TXA3
3. products from cycloxygenase from arachidonate include PGI2 and TXA2
4. PGI2 and PGI3 have approximately the same anti-platelet aggregatory activity, but TXA2 has a more potent platelet aggregator than TXA3
5. thus, EPA shifts balance to anti-platelet aggregation

Question 14

In regards to dyslipidemia, taken at higher doses n-3 PUFA ethyl esters have been shown to reduce plasma ____

Answer 14

TAGs

Question 15

In regards to rheumatologic conditions, n-3 PUFA has anti-inflammatory activity. What is the mechanism?

Answer 15

decreased synthesis of arachidonate derived prostanoids, which are mediators of inflammation

Question 16

In regards to hypertension, higher doses of n-3 PUFAs where shown to reduce blood pressure. What is the mechanism?

Answer 16

altered balance in production of vasoconstrictive prostaglandins and vasodilatory prostacyclin

Question 17

In regards to vision development and disorders, a very high concentration of DHA is found in the ____

Answer 17

retina

Question 18

In regards to vision development and disorders, intake of n-3 PUFAs results in reduced risk of age-related ____ ____

Answer 18

macular degeneration

Question 19

DHA has been shown to be decreased in the plasma and brain of patients with _____

Answer 19

dementia