(OR15-01-23) Strawberry-Derived Microbial Metabolites and Gut Microbes Mediate the Beneficial Vascular Effects of Dietary Strawberries

Objectives: Emerging evidence from our lab and others indicates the vascular beneficial effects of dietary strawberries. However, the role of strawberry metabolites and gut microbes in mediating these effects is unknown. In the present study, we investigated the association between dietary strawberries, gut microbes, metabolites, and vascular health.

Methods: 7-week-old male mice consumed a standard diet (10% kcal fat) (C) or a high-fat diet (60% kcal fat) (HF) and the subgroup of HF received 2.35% freeze-dried strawberry powder (~ 2 human servings) in the diet (HFSB). A subgroup of HFSB received an antibiotic cocktail in drinking water (HFSBAb). At the end of 12 weeks treatment period, the following were assessed: metabolic parameters, vascular inflammation, the composition of gut microbes (by amplification of 16s rRNA gene), and strawberry-derived metabolites (by high-throughput UPLC-MS/MS).

Results: Depletion of gut microbes in HFSBAb mice was confirmed by 16s rRNA amplification. HF mice exhibited an increased vascular inflammation <em>vs</em> C as shown by an increased monocyte binding to the aortic vessel and circulating chemokines (IL8 and MCP1). Dietary strawberries suppressed vascular inflammation in HFSB <em>vs</em> HF mice without changing the metabolic parameters. However, gut microbial depletion abolished the beneficial vascular effects of strawberries in HFSBAb <em>vs</em> HFSB indicating the importance of gut microbes in mediating the bioactivities of strawberries. Further, dietary strawberries suppressed the abundance of opportunistic microbes (<em>Lachnospiraceae</em>) and increased commensal microbes (<em>Lactococcus</em>) that are positively and negatively associated with vascular inflammation, respectively. Serum hippuric acid was negatively associated with indices of vascular inflammation indicating it may be a potential strawberry-derived microbial metabolite. Hippuric acid was also positively associated with commensal microbes and negatively associated with opportunistic microbes.

Conclusions: Our study indicates that a strong association exists between dietary strawberries, gut microbes, plasma metabolites, and vascular health. Dietary strawberries may be a potential strategy to improve vascular health.

Funding Sources: NIH-NCCIH and USDA-NIFA