27 Hormonal control of energy metabolism

Question 1

Lipogenesis and ketogenesis is mediated by which hormone(s?)

Answer 1

GH, epinephrine, glucagon, cortisol

2,4,4,1

1. Glycogenolysis: epinephrine, glucagon
2. Gluconeogenesis: glucagon, epinephrine, GH, cortisol
3. Lipolysis and ketogenesis: epinephrine, GH, glucagon, cortisol
4. Proteolysis: Cortisol

Question 2

Proteolysis is mediated by which hormone(s)?

Answer 2

Cortisol

2,4,4,1

1. Glycogenolysis: epinephrine, glucagon
2. Gluconeogenesis: glucagon, epinephrine, GH, cortisol
3. Lipolysis and ketogenesis: epinephrine, GH, glucagon, cortisol
4. Proteolysis: Cortisol

Question 3

Gluconeogenesis is mediated by which hormone(s)?

Answer 3

GH, glucagon, cortisol, epinephrine

2,4,4,1

1. Glycogenolysis: epinephrine, glucagon
2. Gluconeogenesis: glucagon, epinephrine, GH, cortisol
3. Lipolysis and ketogenesis: epinephrine, GH, glucagon, cortisol
4. Proteolysis: Cortisol

Question 4

Glycogenolysis is mediated by which hormone(s)?

Answer 4

epinephrine, glucagon

2,4,4,1

1. Glycogenolysis: epinephrine, glucagon
2. Gluconeogenesis: glucagon, epinephrine, GH, cortisol
3. Lipolysis and ketogenesis: epinephrine, GH, glucagon, cortisol
4. Proteolysis: Cortisol

Question 5

Briefly see this.

1. Excessive plasma free fatty acid from diets leads to the accumulation of long-chain fatty acids acyl-CoAs
2. due to the low energy demad, those acyl-CoAs are incompletely oxidized by mitochondria and formed large lipid droplets.
3. Lipolysis of these droplets generates several lipotoxic precursor e.g. diacyglycerol (DAG) and ceramide

Answer 5

4. Borh of the acyl-CoAs and DAG activate PKC to stimulate serine but not tyrosine phosphorylation on insulin receptor and insulin receptor substrates (IRS)
5. This decreases the association between IRS, PI3 kinase and translocation of GLUT4 vesicles
6. Ceramide decreases the protein kinase B phosphrylation. This also prevents the translocation of GLUT 4 vesicles