The impact of gut microbiota and Aronia melanocarpa on inflammation after a high-fat diet in humanized mouse models

Abstract

Introduction: Chronic low-grade inflammation is exacerbated by high-fat diets (HFDs) and significantly increases the risk of metabolic disorders. Understanding how the gut microbiome influences and counteracts HFD-induced inflammation can inform targeted interventions to alleviate metabolic dysfunction. Aronia melanocarpa is a polyphenolic berry known for its antioxidant and anti-inflammatory impacts. This pilot study investigated how donor inflammation status impacts inflammation in metabolically active tissues in humanized mice after a HFD. Methods: C57BL/6 mice received fecal transplants from human donors with similar metabolic profiles but varying levels of systemic inflammation (low, high). Over eight weeks, mice were given either Aronia melanocarpa or a sugar-matched drink alongside a 6-week HFD rich in sugars and saturated fats. Liver and muscle tissues were collected post-sacrifice for RNA extraction and qPCR, measuring gene expression of C-reactive protein (CRP), interleukin (IL)- 10, IL-1B, IL-6, tumor necrosis factor (TNF)-a, and tumor growth factor (TGF)-b. Given the small pilot sample size, the fold change of observed differences of high and low donor phenotypes within aronia and control mice and the fold change of control and aronia supplementation within high and low phenotypes were used, given the small pilot sample size (n =13). Results: Results showed higher inflammatory gene expression in the liver (6/6 markers) and muscle (3/6 markers) of control mice with the HI inflammation donor than the LO inflammation donor. Inflammatory gene expression was greater in the liver (1/6) and muscle (2/6) with the HI inflammation donor than the LO inflammation donor in aronia mice. Conclusion: These findings suggest that the inflammatory phenotype may be transferred with the gut microbiota, and low-inflammatory phenotypes may confer protection against HFD- induced inflammation. This highlights potential strategies for managing inflammation associated with HFD and its complications. Further research could uncover novel avenues for inflammation management in metabolic disorders.