Neuropeptide Y interaction with dopaminergic and serotonergic pathways: interlinked neurocircuits modulating hedonic eating behaviours.

Independent from homeostatic needs, the consumption of foods originating from hyperpalatable diets is defined as hedonic eating. Hedonic eating can be observed in many forms of eating phenotypes, such as compulsive eating and stress-eating, heightening the risk of obesity development. For instance, stress can trigger the consumption of palatable foods as a type of coping strategy, which can become compulsive, particularly when developed as a habit. Although eating for pleasure is observed in multiple maladaptive eating behaviours, the current understanding of the neurobiology underlying hedonic eating remains deficient. Intriguingly, the combined orexigenic, anxiolytic and reward-seeking properties of Neuropeptide Y (NPY) ignited great interest and has positioned NPY as one of the core neuromodulators operating hedonic eating behaviours. While extensive literature exists exploring the homeostatic orexigenic and anxiolytic properties of NPY, the rewarding effects of NPY continue to be investigated. As deduced from a series of behavioural and molecular-based studies, NPY appears to motivate the consumption and enhancement of food-rewards. As a possible mechanism, NPY may modulate reward-associated monoaminergic pathways, such as the dopaminergic and serotoninergic neural networks, to modulate hedonic eating behaviours. Furthermore, potential direct and indirect NPYergic neurocircuitries connecting classical homeostatic and hedonic neuropathways may also exist involving the anti-reward centre the lateral habenula. Therefore, this review investigates the participation of NPY in orchestrating hedonic eating behaviours through the modulation of monoaminergic pathways.