<i>Pulicaria incisa</i> Infusion Modulates the Gut Microbiota and Improves Locomotor Activity and Exploratory Behavior in Aging Mice

ABSTRACT The aging process involves chronic inflammation and oxidative stress in the brain, which increase susceptibility to neurodegeneration, age‐related pathologies, and anxiety‐like behavior. Dysbiosis of the gut microbiota and increased anxiety‐like behavior are related to one another and are both characteristic of aging. This study investigated the effects of an infusion prepared from the plant Pulicaria incisa ( Pi ) on locomotor activity, exploratory behavior, and the composition of the microbiomes of aging mice, with a focus on its mechanism of action. An open‐field test was used to evaluate locomotor activity and exploratory behavior in old mice that had been fed Pi infusion daily. Changes in the gut microbiota were examined using 16S rRNA gene sequencing and subsequent bioinformatic analysis. The antagonistic activity of the probiotic Bacilli against pathogenic bacteria was evaluated in vitro and in vivo using a C. elegans model. We observed a significant improvement in locomotor activity and exploratory behavior of aging mice treated with Pi infusion, accompanied by a reduced number of pyknotic neurons in the hippocampus, as compared to age‐matched controls. Analysis of gut microbiota revealed that Pi consumption restored levels of commensal Bacilli and significantly reduced Clostridia levels in Pi ‐treated aging mice, as compared to untreated aging mice. These changes might be associated with the Pi ‐induced antagonistic activity of probiotic Bacilli against pathogenic bacteria. Our findings suggest that consuming Pi infusion can alleviate aging‐induced reduction in locomotor activity and exploratory behavior, and gut–microbiota dysbiosis. They support the use of this prebiotic infusion as a nutritional intervention.