TBL 9 Glycolysis and PPP

Question 1

Vitamin B1 is a cofactor in which of the following enzymes and pathway in which they belong

Answer 1

Pentose Pathway (ribose 5-phosphate)

formation of acetyl coa (pyruvate dehydrogenase)

Citrate acod cycle ( alpha KG dehydrogenase)

Branched chain amino acid ulilization (BCKDH)

non-oxidative phase of PPP (transketolase)

Question 2

risks people for Vit B 1 deficiancy

Answer 2

alcoholics, starvation, pregancy, high carb diet, Dyalysis( B1 leaves more) vomitting, Chronic diarrhea, GI surgery,

alcohol reduced absorbption

Question 3

Vitamin B1 deficiency disorders

Answer 3

Beriberi (dry- cardiovascular, Dry - neurological)

Wernickes(reversible)

-korsakoff (non-reversible) syndrome (in alcoholics)

Question 4

Dry Berberi vs wet beriberi

Question 5

NADH, FADH2 are derived from what vitamins

Answer 5

NADH, FADH2- reduced molecules that are made from Vitamin B3 and B2
respectively

Question 6

CoA and Lipoamide are cofactors for ___

Answer 6

PDH (pyruvate dehydrogense) and TCA

Question 7

biotin is ____

Answer 7

vit B7

Question 8

Tetrahydro Folate is a vitamin_____derivative

Answer 8

B9

Question 9

TPP is _____ derivative

Answer 9

B1

Question 10

in pregnant women, what leads to gestatational diabetes?

Answer 10

placenta produces lactogen and mimics growth hormone, so it opposes insulin, so glucokinase activity is also reduced since insulin increases glukokinase to reduce sugar levels in blood

Question 11

pyruvate kinase hormone regulators

Answer 11

Glucagon and epinephrine will favor gluconeogenesis

Question 12

what steps in glycolysis are irreversible

Answer 12

PFK-1 and pyruvate kinase

Question 13

diease related to pyruvate kinase deficiency:

Answer 13

autosomal recessive

when pyruvate kinase cant make ATP leads to RBC lysis since low ATP causes messed up Na+/K+ ATPase pump, irregular ion balance —> cell swells and lysis.

this will shift gluycolysis to produce 2,3 BPG from 1,3 BPG so cells can deliver more oxygen!!

Question 14

what happens when there is not enough oxygen, what will be produced in our cells?

Question 15

what cells rely on lactate production?

Answer 15

red, white blood cells, kidney medulla, eye, skeletal muscle

Question 16

lactic acidosis can lead to_____

Answer 16

Poor oxygen transport

anemia: not enough RBC/Hb (acidic
chronic lung disease
weak breathing

Question 17

what are other Lactate dehydrogenase dysfunctiions

Answer 17

-Alcoholism or acute alcohol poisoning: too much NADH
-Too much exercise: use all NADH so fermentation instead
-GSD Type I: cant convert G6P to glucose (dont have to know yet)
-Drug use or other liver dysfunction

Question 18

what are the products of PPP

Answer 18

NADPH, Ribose 5 Phosphate, Glucose 6 phosphate

Question 19

what is the oxidative phase of PPP

Answer 19

Glucose 6 P makes Ribolose 5 phosphate and makes 2 NADPH

NON-REVERSIBLE

Question 20

ribose 5 phosphate is made from the ____ phase

Answer 20

non-oxidative phase

makes nucleotides and other sugars

Question 21

what are the steps in the oxidative phase of PPP ( name 2 key enzymes )

and what does each enzyme produce?

Answer 21

key enzymes:

Glucose-6-phosphate dehydrogenase (G6PD) : produces 6-phosphoglucolactone and NADPH

6- phosphogluconate dehydrogenase

produces Ribolose-5-phosphate
NADPH and CO2

Question 22

what is NADPH used for?

Answer 22

for anabolic reasons:
fatty acid synthesis, make steroid hormones in adrenal cortex, make sex hormones in mammary glands

Glutathione reduction (antioxidant product)
drug detox: liver: CYP system

immune cells: have NADPH oxidases that oxidise marked pathogens

Question 23

how does NADPH help regulate the Respiratory Burst?

Answer 23

hep form free radicals(hyperchhlorite and H2O2) to aid killing of pathogens and also generate reduced glutathione to neutralize remaining H2O2

Question 24

what are the two enzymes you should know in the non-oxidative phase of PPP?

Answer 24

Transketalose: trasnfers two carbons with the help of B1 (thiamine)

transaldose: transfer 3 carbons

together form bigger sugars

Question 25

where is vitamin B1 needed?

Answer 25

in transketolase

in pyruvate dehydrogenase complex

alpha-ketoglurate dehydrogenase complex

Question 26

if transketolase activity is low then that means

Answer 26

there is not enough vitamin B1

Question 27

explain G6PDD and clinical symptoms

Answer 27

it is an X-linked disorder
female carriers have advatage over not getting infected with Malaria

its creates short life spain of RBC

most people are asymtomatic unless the RBC becomes more stressed than usual

Question 28

explain how glutathione works?

Answer 28

reduced from of glutathione is used to clear out oxidants

2G-SH (active because reduced and ready to work)

G-s-s-G (already oxidezed) needs to be regenirated by glutathione reductase

glutathione reductase needs NADPH (from G6PD) to reduce Glutathione again to work more

cells will die from metrabolic poisons without glutathione

Question 29

what are some events that can lead to high oxidative stress?

Answer 29

oxidative medications: antibiotics, antipyretics, antimalerials, sulfonamides

oxidant foods : fava beans

infections; oxidants during inflamation

Question 30

oxidative medications

Answer 30

antimalarials, antibiotics, sulfonamides, antipyrecs