Discussion
In db/db mice administered with HKC and TFA, 7 flavonoid prototypes and 38 metabolites were identified. The related metabolic pathways at Phases I and II reactions included dehydroxylation, deglycosylation, hydrogenation, methylation, glucuronidation, sulphation, and corresponding recombined reactions. Quercetin, isorhamnetin, quercetin sulphate, quercetin monoglucuronide, and isorhamnetin monoglucuronide presented a high exposure in the serum and kidney of db/db mice. Thereby, the present study provides a pharmacodynamic substance basis for better understanding the mechanism of A. manihot (L.) Medik for medication of DN.
Methods
HKC (0.84 g/kg/d) and TFA (0.076 g/kg/d) or vehicle were respectively administered daily via oral gavage in db/db mice for 4 weeks. The metabolism fate of the main metabolites of HKC in serum, liver, kidney, heart, jejunum, colon, jejunal contents, colonic contents, and urine of db/db mice were analyzed with a comprehensive metabolite identification strategy.