Endocrine Weight Loss Cortisol, Stress Hormones, and Body Composition

Question 1

Chronic elevation of cortisol promotes central (visceral) obesity primarily through which mechanism?

Accepted Answer

Activating glucocorticoid receptors in visceral adipocytes, promoting fat uptake and inhibiting lipolysis

Answer

Visceral adipocytes express high levels of glucocorticoid receptors and 11β-HSD1 (which converts cortisone to cortisol locally), making them especially sensitive to cortisol's fat-accumulating effects.

Question 2

Cushing's syndrome due to a pituitary ACTH-secreting adenoma is called Cushing's disease and produces the classic body composition change of:

Accepted Answer

Central obesity with proximal muscle wasting, moon face, and buffalo hump

Answer

Chronic glucocorticoid excess in Cushing's syndrome causes redistribution of fat to central, facial, and dorsocervical depots while simultaneously causing protein catabolism and proximal muscle wasting.

Question 3

The 1 mg overnight dexamethasone suppression test is used to screen for Cushing's syndrome. An abnormal result is a morning cortisol of:

Accepted Answer

>1.8 mcg/dL (failure to suppress)

Answer

A morning serum cortisol >1.8 mcg/dL after 1 mg dexamethasone the night before indicates failure of hypothalamic-pituitary-adrenal axis suppression, warranting further workup for Cushing's syndrome.

Question 4

Psychological stress promotes weight gain through cortisol's effect on:

Accepted Answer

Directly inhibiting adipocyte lipolysis and increasing cravings for high-calorie foods

Answer

Stress-induced cortisol elevates appetite (particularly for calorie-dense, rewarding foods), inhibits lipolysis, and promotes visceral fat deposition through glucocorticoid receptor activation.

Question 5

Which enzyme locally amplifies cortisol concentration within adipose tissue, particularly visceral fat?

Accepted Answer

11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1)

Answer

11β-HSD1 regenerates active cortisol from inactive cortisone within fat tissue; its overexpression in visceral adipose tissue amplifies glucocorticoid action locally and contributes to central obesity.

Endocrine Weight Loss Practice Test

Endocrine Weight Loss Practice Test

Endocrine Weight Loss Cortisol, Stress Hormones, and Body Composition