Short-term exposure to banana starch induces low-grade colonic inflammation in healthy mice

Resistant starch, recognized as a prebiotic, has demonstrated significant potential in alleviating various disease models but its intestinal safety study has been always overlooked. Banana starch (BS), a rich source of resistant starch, and its derived nanoparticles have been implicated in intestinal barrier dysfunction in our previous study. However, the short-term effects of BS consumption on gut health in healthy bodies remain unclear. Here, we show short-term consumption of BS and banana starch nanoparticles (BSNs) induces low-grade colitis in healthy mice. Specifically, BS significantly reduces the number of colon goblet cells, elevates the expression of TNF-α, IL-1β, and IL-6, and shortens colon length, collectively contributing to intestinal barrier damage and the onset of colitis. Mechanistic studies indicate that BS and BSNs disrupt gut microbiota homeostasis, downregulate the expression of proteins like ZO-1, Occludin, and Claudin-1, and impair the structural integrity of colonic tight junctions. Correlation analysis further underscores a strong association between gut microbiota composition and colitis-related markers. These findings indicate that prolonged consumption of BS and BS-derived nanoparticles may pose significant risks to intestinal health, warranting further attention.