What is the Origin of Leptin Ghrelin Axis?

The concept of this axis emerged from the sequential discovery of the two primary peptide hormones: Ghrelin was identified in 1999, and Leptin was discovered earlier in 1994. The term "Axis" is used to describe the functional and anatomical connection between the peripheral organs (stomach, adipose tissue) and the central nervous system, particularly the hypothalamus, which integrates these signals. This discovery fundamentally shifted the understanding of appetite control from a purely psychological drive to a complex, tightly regulated endocrine process.

What is the Mechanism of Leptin Ghrelin Axis?

The mechanism involves the opposing effects of the two hormones on key neuronal populations in the arcuate nucleus of the hypothalamus. Leptin binds to its receptors on anorexigenic neurons, stimulating the release of satiety-promoting neuropeptides, while simultaneously inhibiting orexigenic neurons. Ghrelin, often referred to as the "hunger hormone," stimulates the orexigenic neurons via its receptor, promoting food-seeking behavior. The ratio and sensitivity to these signals determine the body's set point for energy intake and expenditure, ensuring energy reserves are maintained over time.

Leptin Ghrelin Axis

Meaning

The Leptin Ghrelin Axis represents the critical neurohormonal signaling pathway that governs the physiological regulation of appetite, satiety, and energy balance within the body. Leptin, produced by adipose tissue, acts as a long-term signal of energy sufficiency, promoting satiety and decreasing appetite. Conversely, Ghrelin, primarily secreted by the stomach, acts as a short-term signal of hunger, stimulating food intake. The coordinated, reciprocal action of these two hormones is essential for maintaining metabolic homeostasis and is frequently implicated in the pathophysiology of obesity and metabolic syndrome. Disruption of this delicate axis can profoundly impact weight management and overall metabolic health.