Supplementary Material for: Modulation of Microbiota-Gut-Brain Axis by Berberine Resulting in Improved Metabolic Status in High-Fat Diet-Fed Rats

<i>Objective: </i>To investigate whether or not berberine could improve metabolic status of high-fat-fed rats through modulation of microbiota-gut-brain axis. <i>Methods:</i>Berberine was administered on high-fat-fed Sprague-Dawley rats. Brain-gut hormones were detected, and changes of gut microbiota were analyzed by 16S rRNA gene sequencing. <i>Results:</i> Berberine could reduce weight gain and lipolysis in the high-fat diet-fed group. Moreover, trends of ameliorated insulin resistance and decreased endogenous glucose production were observed. In addition, the microbiota-gut-brain axis was found to be modulated, including structural and diversity changes of microbiota, elevated serum glucagon-like peptide-1 and neuropeptide Y level, decreased orexin A level, up-regulated glucagon-like peptide-1 receptor mRNA level as well as ultra-structural improvement of the hypothalamus. <i>Conclusion:</i> Taken together, our findings suggest that berberine improved metabolic disorders induced by high-fat diet through modulation of the microbiota-gut-brain axis.