Appetite change profiles in depression exhibit differential relationships between systemic inflammation and activity in reward and interoceptive neurocircuitry
According to earlier studies, hunger alterations associated with depression may be a sign of underlying neural and inflammatory variations among Major depressive disorder (MDD) subgroups. MDD is characterized by changes in hunger, but little neuroscientific research has been done to understand why some people become depressed and have increased appetites while others have reduced appetites. In this study by Cosgrove et al. (2020), the authors investigated the connection between brain circuits promoting food hedonics in people with MDD and systemic inflammation, in a population of 64 participants (n = 31 current, untreated MDD and n = 33 healthy controls [HC]) gave blood samples for inflammatory marker C-reactive protein (CRP) analysis. They also underwent a functional magnetic resonance imaging (fMRI) scan in which they rated how pleasant they thought various food stimuli were. Analysis of the results showed that All MDD patients showed a greater positive correlation between CRP and linkage between striatal activity and perceived food pleasantness compared to HC. Furthermore, higher CRP levels in blood were associated with stronger coupling between the activity of the orbitofrontal cortex and the anterior insula, which suggested that eating was pleasurable in MDD patients with enhanced appetite. The authors conclude that these results imply that systemic low-grade inflammation in MDD patients is linked to variations in reward- and interoceptive-related neural circuits when drawing hedonic conclusions about dietary cues. To sum up, immunologic changes may influence hunger and conclusions about food incentives in people with MDD, supporting the existing findings regarding the physiological subgroups of this disorder. [NPID: fMRI, Major Depressive Disorder, inflammation, C reactive protein, appetite]
Year: 2020