<prompt> Leptin is secreted by-OvariesAdipose tissueLiverHypothalamus  <response>: Ans. is b i.e., Adipose tissue Leptin Leptin is a protein hormone produced by fat cells of adipose tissue. It acts on hypothalamus to reduce food intake, decrease lipogenesis and increase lipolysis, thereby reducing the body fat stores. The effect of leptin on appetite is mediated through a-MSH a-melanocyte stimulating hormone, a proopiomelanocortin POMC derivative. Leptin acts by increasing the synthesis of POMC which is converted into a-MSH. a-MSH acts through melanocortin-4 receptors to depress appetite. Leptin also inhibits the secretion of Agouti-related peptide AgRP, a neuropeptide that increases food intake. Plasma leptin levels are proportional to the amount of body fat and are therefore higher in women and obese individuals. Leptin level is increased ini Obesityiv Insulinii Emotional stressv Dexamethasoneiii Estrogen Leptin level is decreased by:i Sleep deprivationiii Exerciseii Testosterone androgeniv Starvation 