Leptin (22-56), human, is a peptide fragment derived from the full-length leptin protein, which plays a critical role in regulating energy balance and appetite. This specific fragment is often utilized in research to study the mechanisms of leptin signaling and its interactions with leptin receptors. It helps scientists understand how leptin influences metabolic processes, including fat storage and hunger regulation. Additionally, it is used in developing therapeutic strategies for obesity and metabolic disorders by exploring the effects of leptin fragments on appetite suppression and energy expenditure. Its application is primarily focused on advancing knowledge in endocrinology and metabolic disease research.