Glucuronic acid metabolites of phenolic acids target AKT-PH domain to improve glucose metabolism.

Objective: Phenolic acids widely exist in the human diet and exert beneficial effects such as improving glucose metabolism. It is not clear whether phenolic acids or their metabolites play a major role Methods: Three insulin resistance models Results: The results showed that CA4G and FA4G were more potent than their parent compounds in increasing glucose consumption. AKT was predicted to be the key target of CA4G and FA4G by network pharmacology analysis. The fluorescence quenching test confirmed the more potent binding to AKT of the two metabolites compared to their parent compounds. The molecular docking results indicated that the carbonyl group in the glucuronic acid structure of CA4G and FA4G might bind to the PH domain of AKT at the key Arg-25 site. CA4G and FA4G inhibited the translocation of the AKT PH domain to the membrane, while increasing the activity of AKT. Western blot analysis demonstrated that the metabolites could increase the phosphorylation of AKT and downstream glycogen synthase kinase 3β in the AKT signaling pathway to increase glucose consumption. Conclusion: In conclusion, our results suggested that the metabolites of phenolic acids, which contain glucuronic acid, are the key active substances and that they activate AKT by targeting the PH domain, thus improving glucose metabolism.