What is the role of leptin in weight management?

Inhibits appettite. Leptin hormone tells your brain that you are full and do not need to eat anymore.
Satiation. Leptin is a hormone which is released from fat cells and regulates the fat stores in the body. If the body has sufficient amounts of fat, satiety signals will be sent to the hypothalamus, the region of the brain which is responsible for regulating appetite and metabolic rate. If the body lacks adequate amounts of fat, another hormone, known as ghrelin, will stimulate sensations of hunger.