Feast or Famine

Question 0

Is obesity just lots of adipose tissue?

Answer 0

No, there’s fat deposition in many organs.

Question 1

Effect of NPY on appetite? Of alpha-MSH?

Answer 1

NPY increases food intake.

alpha-MSH increases satiety.

Question 2

Where is leptin produced? What happens when you don’t have it?

Answer 2

Leptin is produced in fat cells.

If not present, no negative feedback from adipose to suppress appetite -> just keep feeding and become obese.

Question 3

What happens if melanocortin-4 is knocked out?

Answer 3

Obesity.

Question 4

Why is being sarcopenic (not much muscle mass) bad?

Answer 4

Less muscle means you can’t take up glucose as well.

Question 5

Why are extra-adipose triglycerides bad?

Answer 5

ROS…ER stress… inflammation… impairs insulin signaling -> insulin resistance

Question 6

What’s the most effective form of bariatric surgery for weight loss?

Answer 6

Roux-en-Y gastric bypass to more distal small intestine.

Question 7

What is dumping syndrome?

Answer 7

Orthostatic hypotension / hypoglycemia in response to feeding.

Question 8

3 cytokines that can drive cachexia?

Answer 8

TNF, IL-1, IL-6

Question 9

3 drivers of anabolism in skeletal muscle?

Answer 9

Follistatin
IGF-1
Androgens

Question 10

3 pathways for catabolism in skeletal muscle?

Answer 10

Autophagy
Ubiquitin
Myostatin

Question 11

3 features of management of cachexia?

Answer 11

Controlled re-feeding.
Treat underlying cause.
Rev up anabolism? -> megesterol, cannabinoids, GNRH, myostatin inhibitors…