Rôle du GPR120 microglial dans la neuro-inflammation et le comportement anxio-dépressif
GPR120 is a peripheral and central receptor present in the body, known for its anti-inflammatory role and beneficial role on metabolism. At the central level, it is strongly expressed in microglia, brain cells that act as immune cells with astrocytes. There is increasing evidence of the protective role of microglial GPR120 in neuroinflammation and its potential to improve behavior, including reducing signs of anxiety and depression in rodents and human. In the present study, four groups of mice each received different diets in vivo including one rich in omega-3 fatty acids (GPR120 agonist) following a previous diet rich in pro-inflammatory saturated fatty acids. The behavior of these mice was subsequently studied to evaluate the effect of the omega-3 supplementation in vivo on anxiety and depression. Other parameters were also measured after the supplementation, such as blood glucose and circulating lipid profile. In a second experiment, the activation of the GPR120 was tested in vitro to study its role in a context of acute inflammation. Primary microglial cells from mouse brain were exposed to various agonists of GPR120 (CpdA and omega-3) in acute inflammation (LPS). The effect on inflammation was determined by the measurement of the expression of several inflammatory cytokines (TNF-α, IL-6, IL-1β and MCP-1) and the activation of microglia. The results obtained in vivo show that the supplementation in omega 3 fatty acids acts positively on the behavior and reduces the signs of anxiety and depression in mice. It also improves both the blood glucose and the profile of circulating lipids. On the other hand, the GPR120 receptor reduces the neuroinflammation, the level of pro-inflammatory cytokines and the activation of microglia in vitro.
GPR120 Omega-3 fatty acids Neuroinflammation Behavior Metabolism