Neuroinflammation in the Brain Influences Childhood Weight Gain
Post by Leigh Christopher
The takeaway
The neurobiological changes underlying weight gain in youth are not clearly understood. This research shows that there is a reciprocal relationship between neuroinflammation in the brain and weight gain in youth, suggesting a cycle exists between the two.
What's the science?
Obesity is a growing public health concern that can begin in childhood. Obesity can increase the risk of diabetes and heart disease and is also known to impact mental health. The nucleus accumbens is a brain region known to be involved in motivation and reward. Furthermore, glial cell proliferation in the nucleus accumbens is known to be an indicator of neuroinflammation and has been linked to weight gain in youth. This week in The Journal of Adolescent Health, Rapuano and colleagues investigate how nucleus accumbens cell density changes over time and how these changes are connected to weight gain in youth.
How did they do it?
The authors used a large-scale, publicly available dataset including data from over 11,000 youth throughout development. In this dataset, youth underwent magnetic resonance imaging (MRI) scans, and data such as Body Mass Index (BMI), waist circumference, and diet were recorded along with many other variables. With the use of MRI scans and longitudinal modeling, the authors were able to measure changes in cell density in the nucleus accumbens over a two-year period, and assess how these changes related to diet and waist circumference, an important metric for predicting weight gain in adolescents.
What did they find?
The authors found that baseline nucleus accumbens cell density (indicative of neuroinflammation) predicted an increase in waist circumference after two years and that in turn, baseline waist circumference predicted a two-year change in nucleus accumbens cell density. They also found that nucleus accumbens cell density mediated the relationship between diet and weight circumference. These results suggest a cycle, where increased food intake leads to glial cell proliferation and weight gain, which further perpetuates the proliferation of cells in the nucleus accumbens. Importantly, the results were not affected when controlling for confounding variables like genetics, education, and income.
What's the impact?
This study found a reciprocal relationship between cell density in the nucleus accumbens and weight gain, consistent with the ‘vicious cycle’ hypothesis of diet-induced brain changes, leading to weight gain. Furthermore, this research established the role of neuroinflammation in the nucleus accumbens as a key neurobiological change underlying weight gain in youth - highlighting its relevance as a target for future research.