Nutrition/ Metabolism

Question 1

What aa is essential for urea cycle in cats?

Answer 1

Arginine needed for ammonia to convert to urea

Question 2

Ammonia & glutamate

Answer 2

NH3 + H+ <—> NH4+
Glutamate + NH4+ <—> glutamine

Question 3

Ammonia loss/gain in liver, GI tract, skeletal mm, CBR

Answer 3

Liver: net ammonia loss (converted to urea via urea cycle), glutamine synthesis ( uses ammonia)
GI Tract: net ammonia gain (bacteria metabolism of protein and urea to ammonia), glutamine catabolism
Skeletal mm: ammonia sink, buffer by making glutamine; therefore when mm wasted, lose the ability to act as a buffer for ammonia
CBR: ammonia loss or gain (glutamine synthesis by astrocytes, glutamine catabolism)
Kidney: ammonia loss or gain (glutamine synthesis, throw our urea, glutamine catabolism)

Question 4

Ammonia and hepatic encephalopathy signs

Answer 4

Ammonia + glutamate <—> glutamine
Glutamine crosses over to presynaptic terminal, breaks down to glutamate —> diffuse to post-synaptic terminal and will initiate cause excitation then depression

Question 5

What electrolyte derangements can worsen HE?

Answer 5

HypoNa
HypoK

Question 6

Which can worsen HE? Alkalosis vs acidosis?

Answer 6

Alkalosis

Question 7

Which protein source is beneficial for patients with HE?

Answer 7

Non-meat based protein (soy-based diet good, egg white, low fat cottage cheese)

Also OK to feed i/d diet

Question 8

Essential FAs

Answer 8

Dog: Linolenic, linoleic acid
Cats: Above + arachidonic acid

Question 9

Cat and Vitamin A

Answer 9

Unable to turn beta carotene into Vit A, need Vit A in diet (essential)

Question 10

Cat and thiamine

Answer 10

Cats need more thiamine than dogs.

Question 11

Cat and niacin

Answer 11

Cats cannot convert tryptophan into niacin, therefore, required in diet

Question 12

Cats and taurine deficiency

Answer 12

Have lower enzyme to make taurine —> become easily deficient
Deficiency’s causes retinal degeneration, DCM, reproductive failure

Taurine is used in cats (rather than glycine) for bile acid conjugation.

Question 13

Deficiency in Vit A

Answer 13

Night blindness
Growth of epithelial cells (skin, skeletal growth, reproductive, keratinization of cornea)

Question 14

Cat and glucokinase

Answer 14

Relatively deficient in glucokinase (convert glucose to G6P)
Therefore, decrease ability to use CHO for energy

Question 15

What are the essential aa for cats?

Answer 15

Arginine - for urea cycle
Taurine - DCM if deficient

Question 16

Important aa for SI vs LI

Answer 16

SI: glutamine
LI: butyrate

Question 17

Refeeding syndrome

Answer 17

HypoK
HypoP
HypoMg
Glucose intolerance
Thiamine (B1) deficient

Question 18

Examples of omega 3 and omega 6 FA.

Answer 18

Omega 3: DHA, EPA, ALA (alpha-linolenic acid)

Omega 6: LA (linoleic acid), AA (arachidonic acid)

Question 19

Most common dietary FA

Answer 19

Most common fatty acids- stearic, oleic, palmitic,

Question 20

Lipolysis

Answer 20

TG —> glycerol + FA

1. Glycerol —> pyruvate —> glucose
2. Beta oxidation of FA —> acetyl coA —> used in TCA cycle

Question 21

Ketone bodies

Answer 21

B-hydroxybutyrate, acetone, acetoacetate

Question 22

Cat nutrition peculiarities

Answer 22

AA: Need taurine, arginine
Vit: Need Vit A, D, B3 (niacin)
FA: Cats also need more thiamine (B1)

Question 23

Vit B - match numbers and name

Answer 23

B1: Thimine
B2: Riboflavin
B3: Niacin
B5: Panthotenic acid
B6: Pyridoxine
B9: Folic acid
B12: Cobalamin

TRaiNing PuP FoC

Question 24

What is the ornithine cycle?

Answer 24

Toxic ammonia undergo ornithine cycle to create urea (excreted through kidneys)

Question 25

Glycolysis vs Cori cycle

Answer 25

Under aerobic condition:
Glucose —> pyruvate —> acetyl coA (enters citric acid cycle/Kreb cycle

Under anaerobic condition in the MUSCLE:
Glucose <—> pyruvate <—> lactate

Question 26

Hexokinase vs glucokinase

Answer 26

Both convert glucose to G6P

Hexokinase - present in all tissues
Glucokinase - present in liver and pancreas (only active when hyperglycemic)

Cats have NO glucokinase —> have longer post-prandial hyperglycemia; predispose to Type 2 DM

Question 27

Glycolysis
Glycogenolysis
Gluconeogenesis

Answer 27

Glycolysis - breaks down glucose to pyruvate
Glycogenolysis - breaks down glycogen
Gluconeogenesis - making glucose from protein/lipid

Question 28

Transporters involved in sugar absorption

Answer 28

SGLT1 and GLUT5 at apical membrane
GLUT2 basolateral membrane

*SGLT1 = glucose and galactose
GLUT5 = fructose

Question 29

Zinc responsive dermatosis

Answer 29

2 types:
Type 1: normal zinc level but cannot process it appropriately (Nordic breed, Boston terrier @ ear tip)

Type 2: nutritional deficiency

Hyperkeratotic

Question 30

Uric acid and purine metabolism

Answer 30

Purine —> inosine and hypoxanthine
Hypoxanthine —> xanthine and uric acid

allopurinol prevents conversion of hypoxanthine to xanthine and Uric acid

Exogenous source of purine includes meat, fish, organ

Uric acid cystolith form in highly acidic urine, hyperuricosuria,

Dietary restriction of protein, purine + use allopurinol

Question 31

Urate cystolith associated with?

Answer 31

1. Portovascular anomalies
2. Uric acid transporter mutation (SLC2A9)
3. Idiopathic in cats

Question 32

Rx for urate

Answer 32

Diet: purine restricted, alkalinizing, diuretic diet (u/d)
Allopurinol