A groundbreaking study has shed light on the intricate communication mechanisms between the brain and the gut, revealing a direct link between gut bacteria and food addiction. An international team of researchers has pinpointed certain gut bacteria associated with the development of food addiction in both mice and humans, contributing to obesity. Additionally, they have identified bacteria that may have protective effects against food addiction.
Presented at the Federation of European Neuroscience Societies Forum 2024 and published in the journal Gut, this research highlights the potential for new therapeutic approaches to treat food addiction and related eating disorders. Professor Elena Martín-García from the Universitat Pompeu Fabra, Barcelona, Spain, emphasized the multifactorial origins of food addiction, including alterations in the gut microbiome. Until now, the mechanisms underlying this behavioral disorder were largely unknown.
Professor Rafael Maldonado, who leads the Laboratory of Neuropharmacology-NeuroPhar, underscored the significance of these findings. He suggested that identifying new biomarkers for food addiction and evaluating the potential use of beneficial bacteria as treatments could provide effective therapeutic approaches for obesity-related behaviors, which currently lack adequate treatments.
Using the Yale Food Addiction Scale, YFAS 2.0, Professor Martín-García diagnosed food addiction in both mice and humans. The scale, which includes 35 questions for humans, was adapted for mice to assess persistent food-seeking, high motivation to obtain food, and compulsive behavior. The researchers found an increase in Proteobacteria and a decrease in Actinobacteria and Blautia in food-addicted mice. Similar bacterial changes were observed in humans diagnosed with food addiction.
Professor Martín-García's team investigated the protective effects of prebiotics, such as lactulose and rhamnose, which increase Blautia levels in the gut. Administering these prebiotics to mice resulted in significant improvements in food addiction behaviors. Similarly, oral administration of the probiotic Blautia wexlerae also led to notable improvements, highlighting the potential protective effects of certain gut bacteria against food addiction.
The research team also explored the role of microRNAs, miRNAs, in food addiction. These small molecules regulate gene expression and are involved in various cellular processes. Using a technique called Tough Decoy, TuD, to inhibit specific miRNAs in the medial prefrontal cortex, mPFC, of mice, the researchers produced mice vulnerable to developing food addiction. They found that inhibition of miRNA-29c-3p and miRNA-665-3p promoted food addiction behaviors, suggesting these miRNAs act as protective factors against food addiction.
Professor Maldonado emphasized the importance of understanding the neurobiology of eating control, which is crucial for addressing obesity and related disorders. The team is now exploring the interaction between gut microbiota and miRNA expression in the brain to further understand these mechanisms.
Professor Richard Roche from Maynooth University, Ireland, highlighted the significance of this research in understanding compulsive eating and food addiction. He noted that environmental factors and food availability contribute to these disorders, but the role of gut bacteria in brain function is a crucial piece of the puzzle. The findings open the door to developing new treatments for eating disorders, emphasizing the need for continued research in this area.
As the global prevalence of obesity and eating disorders continues to rise, understanding the complex interplay between gut microbiota and brain function offers a promising avenue for innovative treatments. The research led by Professors Martín-García and Maldonado represents a significant step forward in addressing these pressing health issues.
