JOURNAL OF ANIMAL SCIENCE AND VETERINARY MEDICINE
Integrity Research Journals
ISSN: 2536-7099
Model: Open Access/Peer Reviewed
DOI: 10.31248/JASVM
Start Year: 2016
Email: jasvm@integrityresjournals.org
Leptin: The key lean peptide – A review
https://doi.org/10.31248/JASVM2025.621 | Article Number: C5A98C3A8 | Vol.10 (6) - December 2025
Received Date: 29 October 2025 | Accepted Date: 19 December 2025 | Published Date: 30 December 2025
Authors: Diri M.* , Johnson N. C. , Okejim, J. A. and Saturday, L.
Keywords: weight., Appetite, dual theory, peptides, satiety
Feeding ensures the provision of substrates for energy metabolism, a vital process for the survival of every living organism and therefore is subject to intense regulation by brain homeostatic and hedonic systems. At present, our understanding of the circuits and molecules regulating the process has tremendously increased in large part due to the availability of animal models with genetic lesions, involving ‘satiety and appetite centres’. To this point, in this review, roles played in homeostatic modulation of feeding by systemic mediators, involving anorexigenic peptides led by leptin and its major cohorts, such as insulin, alpha-melanocyte-stimulating hormone (α-MSH), cocaine and amphetamine-regulated transcript (CART)and bombesin which act on brain systems utilizing orexigenic peptides led by neuropeptide Y (NPY), agouti-related peptide (AgRP)and their cohorts, such as galanin (GAL), melanin-concentrating hormone (MCH) and orexins (OXs) amongst other mediatorsbased on the dual-control theory of feeding were highlighted and discussed. Furthermore, we examined the mechanisms for taste and nutrient preferences and reward systems that provide food with its intrinsically reinforcing properties and explored the links between the homeostatic and hedonic systems that ensure intake of adequate nutrition. Therefore, the understanding of these molecular networks regulating feed intake could, in the future, lead to designing better therapeutic targets for animal set-point weights and weight loss in obesity.
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