Cardiovascular Health Lecture 1.2 : Pathogenesis of obesity Flashcards
What kind of condition is obesity?
A low grade inflammatory condition.
What is obesity associated with (name 3)?
Many diseases such as diabetes, cardiovascular and renal diseases.
What kind of agent is leptin?
It is a pro inflammatory cytokine.
Where is leptin produced?
In the GIT, placenta and mammary.
Can leptin cross the blood-brain barrier?
Yes.
By how many folds is leptin increased in obese people?
5 fold increase.
What is the function of leptin?
Maintains hunger and satiety.
(decreases hunger, increases satiety).
Low leptin makes you hungry.
Given leptin’s function, why does are leptin levels so high in obese people?
One would think obese people have low leptin levels, but they are very high becasue they have leptin resistance.
What is a possible cause of leptin resistance in obese people?
Impaired transport across the blood-brain barrier.
What happens to leptin levels after a heart failure or infarct?
They increase.
What is the effect of leptin in obese people like vs a healthy person?
Diminished.
How does leptin exert its effects?
Acts on immune cells, increasing inflammatory cytokine release.
What does effect does leptin have in obese people?
Increases adrenaline and noradrenaline in the blood.
What happens after renal deinnervation in obese subjects?
Hypertension reduction in obese dogs.
What is natriuresis, and what effect does leptin have on it? What effect does it have on blood pressure?
It is sodium excretion, and increased leptin increases it. No effect on blood pressure.
What happens to NO levels in obese people? What does it do?
Increased. Vasodilator.
What is TNF-alpha, what makes it, and what happens to its levels in obesity?
A pro inflammatory cytokine made by macrophage monocytes. Leptin acts on it. Increases in obesity.
How does weight loss affect TNF-alpha levels?
Decreases levels.
What are high levels of TNF-alpha correlated with?
Insulin resistance.
What happens when one inhibits TNF-alpha in obese subjects?
Increases insulin sensitivity.
What are TNF-alpha levels like in subjects with cardiovascular diseases? What is a consequence of this?
High. Contribues to atheroma development.
What is adiponectin, and what is it made by?
Anti-inflammatory, made by adipocytes.
What are adiponectin levels like in obese subjects?
Decreased levels.
What effect does leptin have on adiponectin?
Leptin inhibits adiponectin release. Other pro-inflammatory agents also inhibit release.
