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The bioavailability of apigenin-7-glucoside is influenced by human intestinal microbiota in rats

Laura Hanske1, Gunnar Loh, Silke Sczesny

  • 1German Institute of Human Nutrition Potsdam-Rehbruecke, Department of Gastrointestinal Microbiology, 14558 Nuthetal, Germany.

The Journal of Nutrition
|May 1, 2009
PubMed

Insights

Human gut microbiota significantly alters flavone metabolism, producing diverse metabolites in associated rats compared to germ-free models. This impacts flavone bioavailability and bioactivity.

Area of Science:

  • Pharmacology
  • Microbiology
  • Nutritional Science

Background:

  • Flavones, like apigenin-7-glucoside (A7G), are plant compounds with potential health benefits.
  • Their bioavailability and efficacy are influenced by host-microbiota interactions.
  • Understanding A7G metabolism is crucial for its therapeutic applications.

Purpose of the Study:

  • To investigate the impact of human intestinal microbiota on the bioavailability and metabolism of apigenin-7-glucoside (A7G).
  • To compare A7G metabolism in germ-free rats versus human microbiota-associated (HMA) rats.

Main Methods:

  • In vitro incubation of A7G with fecal suspensions to identify metabolites.
  • Administration of A7G to germ-free and HMA rats, followed by analysis of urine, feces, and blood.
  • Enzymatic assays using gut bacteria and rat intestinal mucosa extracts to assess deglycosylation.

Main Results:

  • Human intestinal microbiota converted A7G into apigenin, naringenin, and 3-(4-hydroxyphenyl)propionic acid in vitro.
  • HMA rats exhibited a broader range of A7G metabolites, including naringenin, eriodictyol, and phloretin, compared to germ-free rats.
  • While total A7G excretion was low in both groups, metabolite profiles differed significantly, with HMA rats primarily excreting metabolites in urine.

Conclusions:

  • Human intestinal microbiota profoundly influences A7G metabolism, leading to diverse metabolite profiles.
  • Microbiota-driven metabolism significantly impacts the bioavailability and potential bioactivity of flavones.
  • Targeting gut microbiota could be a strategy to modulate flavone efficacy.

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