Leptin

Definition

Leptin is a hormone predominantly made by adipose cells that helps to regulate energy balance by inhibiting hunger. It plays a key role in body weight regulation and metabolism.

5 Must Know Facts For Your Next Test

1. Leptin levels are directly proportional to the amount of body fat; higher levels are found in individuals with more body fat.
2. Leptin acts on receptors in the hypothalamus to reduce appetite and increase energy expenditure.
3. Mutations in the leptin gene or its receptor can lead to severe obesity due to uncontrolled hunger.
4. Chronic inflammation and high-fat diets can cause leptin resistance, where the body does not respond adequately to leptin signals.
5. Leptin also has roles outside of weight regulation, including influencing reproductive functions and immune responses.

Review Questions

• How does leptin influence appetite and energy balance?
• What is the relationship between body fat and leptin levels?
• What conditions can result from mutations in leptin or its receptor?

Related terms

Insulin:

A hormone produced by the pancreas that regulates blood glucose levels.

Ghrelin:

A hormone produced mainly by the stomach that stimulates appetite.

Hypothalamus:

A region of the brain responsible for regulating many aspects of bodily function, including hunger and energy expenditure.