Applied nutrition flashcards week 2 - signal transduction pathways.txt
Home > Flashcards > Print Preview
The flashcards below were created by user
on FreezingBlue Flashcards
. What would you like to do?
REDOX control enzymes
- Vit C, E, D
- Minerals for Redox control enzymes and antioxidants: Iron, Selenium, Zinc, Coppper
Regulation of protein synthesis importance via signal transduction pathways - example
- MYOSIN: if synthesis is NOT regulated, will have Oversized muscles
- Therefore, need to regulate cell division via regulation of TRANSCRIPTION factors
Why are there so many enzymes in a pathway?
- Need to have LOTS of steps in order to PREVENT accidental ACTIVATION of effectors
- DURATION of SIGNAL is important for how much EFFECTOR you end up with
Important cellular proteins for cell fxn
- 1. Enzymes for chem. rxns
- 2. Actin and myosin for contractile proteins
- 3. Collagen and fibrin for connective tissue
- 4. ANTIBODIES for binding to foreign and non-self shapes
- 5. DNA-binding molecules to REGULATE TRANSCRIPTION
- 6. CELLULAR RECEPTORS: embedded in cell membranes that INITIATE signal transduction PATHWAYS, such as INSULIN receptors, epinephrin, testosterone, estrogen receptors, etc.
NF-kB role in pathways
ACTIVATES Pro-INFLAMMATORY cytokines
2 metabolic pathway examples
- 1. GLYCOGEN synthesis: step off glycolysis
- 2. PENTOSE pathway: Builds NADPH (electrons added to NADP), then breath out carbons as CO2, thereby removing part of glucose as a gas, or it becomes an INERT FAT molecule
- NADPH then used for synthesis rxns, generating ATP in mitochondria
INFLAMMATORY cells EFFECT on surrounding healthy cells
- Inflam. cell radical production (and H202) production can infiltrate HEALTHY cells: RADICAL damage to the membrane of these cells
- Damage causes membrane leakage: causes Calcium influx into cell
- Ca influx ACTIVATES S-T pathways to produce proteins to REPAIR damage, but can also INCREASE DAMAGE (ie; activating LYSOSOMES which kill the cell, or by activating NF-kB to create INFLAMMATORY response)
mostly outside of the cell, but it has an important role as a SIGNALING molecule once it gets into the cell, by activating protein kinase c.
When you exercise, chain of events…
- Up your body temp
- increase you leakage of membrane
- decrease ATP synthesis
- results in need to INCREASE RATE of signaling to combat the decrease ATP
- increasing H202 will increase signaling rate
- Having the right amount of Vit C will allow for activation of S-T pathways
Vit E role and structure and involvement with Vit C
- Fxn is Similar to Vit C: donates electron to RADICAL oxygen, in this case to create stable lipid peroxide
- Structure of Vit E radical: stable due to benzene ring (e- resonates).
- Vit C involvement: VIT C REGENERATES Vit E from its radical form, so it is fxnal
Without Vitamin E..
- Have HIGHER AMOUNT of membranes becoming OXIDIZED
- CANNOT regenerate lipid Antioxidants
MAJOR antioxidants involved in protecting against damage from Reactive oxidant species (ROS)
- Vit C and Vit E: help maintain redox state within NORMAL limits, as ROS are produced constantly during metabolic rxns
- Also rid cell from incoming ROS during other times, such as INFLAMMATION
- B-carotene and glutathione are LESS EFFECTIVE antioxidants
- Also Redox control Enzymes: help maintain redox state within ‘normal’ limits
- Superoxide dismutase: makes H202
- Catalase, TRX, PRX, and GPX: Reduces H202 activity by turning it into H20
- So, in presence of H202, Catalase and other 3 will have INCREASED Activation
- TRX and PRX also act to regulate p38 and JNK pathways
What would you like to do?
Home > Flashcards > Print Preview