Diabetes Metab J.  2012 Dec;36(6):391-398. 10.4093/dmj.2012.36.6.391.

Molecular Mechanisms of Appetite Regulation

• Yu JH
• Kim MS

• KMID: 2174358
• DOI: http://doi.org/10.4093/dmj.2012.36.6.391

Abstract

The prevalence of obesity has been rapidly increasing worldwide over the last several decades and has become a major health problem in developed countries. The brain, especially the hypothalamus, plays a key role in the control of food intake by sensing metabolic signals from peripheral organs and modulating feeding behaviors. To accomplish these important roles, the hypothalamus communicates with other brain areas such as the brainstem and reward-related limbic pathways. The adipocyte-derived hormone leptin and pancreatic beta-cell-derived insulin inform adiposity to the hypothalamus. Gut hormones such as cholecystokinin, peptide YY, pancreatic polypeptide, glucagon-like peptide 1, and oxyntomodulin transfer satiety signals to the brain and ghrelin relays hunger signals. The endocannabinoid system and nutrients are also involved in the physiological regulation of food intake. In this article, we briefly review physiological mechanisms of appetite regulation.

Keyword

Adiposity; Appetite; Hypothalamus; Leptin; Satiety

MeSH Terms

Adiposity
Appetite
Appetite Regulation
Brain
Brain Stem
Cholecystokinin
Developed Countries
Eating
Endocannabinoids
Feeding Behavior
Ghrelin
Glucagon-Like Peptide 1
Hunger
Hypothalamus
Insulin
Leptin
Obesity
Oxyntomodulin
Pancreatic Polypeptide
Peptide YY
Prevalence
Cholecystokinin
Endocannabinoids
Ghrelin
Glucagon-Like Peptide 1
Insulin
Leptin
Oxyntomodulin
Pancreatic Polypeptide
Peptide YY

Figure

• 

  Fig. 1 Hypothalamic nuclei involved in appetite regulation. ARC, arcuate nucleus; AM, amygdala; CC, corpus callosum; CCX, cerebral cortex; DMN, dorsomedial nucleus; FX, fornix; HI, hippocampus; LHA, lateral hypothalamic area; ME, median eminence; OC, optic chiasm; PFA, perifornical area; PVN, paraventricular nucleus; SE, septum; 3V, third ventricle; TH, thalamus; VMN, ventromedial nucleus.

• 

  Fig. 2 A schematic representation of the multiple systems regulating appetite. AgRP, agouti-related peptide; ARC, arcuate nucleus; CCK, cholecystokinin; GLP-1, glucagon-like peptide 1; LHA, lateral hypothalamic area; NPY, neuropeptide Y; NTS, nucleus of the solitary tract; OXM, oxyntomodulin; POMC, pro-opiomelanocortin; PP, pancreatic polypeptide; PVN, paraventricular nucleus; PYY, peptide YY.

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