Lecture 23 Flashcards
What is the inflammation required for muscle hypertrophy?
acute inflammation
What are the inflammatory response mediators?
Inflammatory response is mediated by macrophages neutrophils and monocytes or by cytokines/chemokines.
What are some potential causes of the inflammatory response?
saturated fatty acids, bacterial products, and mechanical stress can cause inflammatory response.
What is the function of immune cells in the inflammatory response?
macrophages monocytes and neutrophils mediate pathogen clearance followed by satellite cell repair.
What are the steps of responding to muscle injury?
Destruction ->repair->remodelling
How long are immune cells typically involved in inflammation for?
immune cell involvement occurs for 14 days
What happens to inflamed muscles if macrophages are not present?
When macrophages are knocked out response of mice to muscle damage is slowed down until macrophages were reintroduced.
Macrophages are necessary for skeletal muscle repair.
What cytokines are expected to be found during sepsis?
TNF, IL-6, IL-10 and other cytokines.
What cytokine is not found in the exercise response but is found during sepsis?
TNF is not activated by exercise. IL-6 is the main cytokine to respond to exercise.
What regulates the amount of IL-6 produced?
IL-6 gets upregulated depending on muscles recruited, exercise intensity, and duration.
What is the function of myokines?
myokines ‘talk’ to other tissue as well as the muscles themselves. these myokines effect muscle hypertrophy, angiogenesis, and fat oxidation, and lipolysis in other tissue.
What is the function of IL-6 in hypertrophy?
IL-6 promotes satellite cell activation and hypertrophy. It activates a receptor called GP130 and this activates the JAK/STAT pathway.
JAK/STAT pathway is linked to the Akt pathway which is involved in inhibiting protein degradation and stimulating protein synthesis.
How does IL-6 binding to GP130 affect JAK and STAT3?
Phosphorylation
Which STAT does IL-6 signal through?
IL-6 generally signals through STAT3.
What happens to LIF during and after exercise?
LIF is significantly upregulated during and after exercise.