Metabolism, tissue distribution and excretion of taxifolin in rat

The metabolism, tissue distribution and excretion of taxifolin in rat after oral administration of taxifolin encapsulated zein-caseinate Nanoparticles (TZP) were studied. The isomerization of taxifolin in rat small intestine and colon was found. Besides isomers, 16 metabolites of taxifolin were identified in rat feces, plasma and urine by UPLC-QTOF-MS. In colon, taxifolin underwent the metabolism of hydration, dehydration and ring fission through the gut microflora. The main metabolites of taxifolin found in plasma and urine were its sulfated, glucuronidated, and/or methylated products. The dynamic variation of taxifolin and its metabolites in tissues and urine were quantified by UPLC-QqQ-MS/MS. Taxifolin and its metabolites could be quickly absorbed and distributed in the tissues, and relatively low concentrations were found in the heart and brain. The feces excretion of taxifolin was determined by HPLC. The total excretion during 24 h was 2.83 +/- 0.80% to its given does, and the maximum excretion was found during 8-10 h post administration. Compared with feces, the excretion of taxifolin and its metabolites in urine was much faster, and the total excretion was 1.96 +/- 0.23% during 12 h.

Automated summary

This study investigated the metabolism, tissue distribution, and excretion of taxifolin in rats after oral administration of taxifolin encapsulated zein-caseinate nanoparticles (TZP). Isomerization of taxifolin was found in the rat's small intestine and colon. UPLC-QTOF-MS analysis identified 16 metabolites of taxifolin in rat feces, plasma, and urine. Taxifolin underwent hydration, dehydration, and ring fission metabolism in the colon through gut microflora. The main metabolites detected in plasma and urine were sulfated, glucuronidated, and/or methylated products of taxifolin. The dynamic variation of taxifolin and its metabolites in tissues and urine were quantified using UPLC-QqQ-MS/MS. Taxifolin and its metabolites were rapidly absorbed and distributed in tissues, with lower concentrations found in the heart and brain. Feces excretion of taxifolin was determined by HPLC, and the total excretion within 24 hours was 2.83 +/- 0.80% of the given dose, with the highest excretion occurring during 8-10 hours post administration. Compared to feces, the excretion of taxifolin and its metabolites in urine was much faster, with a total excretion of 1.96 +/- 0.23% within 12 hours.