Antidiabetic Potentials of Catechin in Combination with Metformin: An In vitro and Molecular Docking Study

Objective: This work aims to evaluate the combined anti-diabetic effects of metformin and catechin in vitro and in silico. Methods: In vitro, anti-diabetic potentials of (α-amylase and α-glucosidase) catechin, metformin, and a combination of catechin and metformin were studied at different concentrations using acarbose as standard. An in silico study determined their binding interactions with α-amylase (PDB ID: 1hvx) and α-glucosidase (PDB ID: 5zcb). The molecular docking study further revealed the binding energy and interacting residues of the docked 3D structure of the catechin, metformin, and acarbose as a standard with the α-amylase and α-glucosidase receptors. Results: The result showed that a 100 μg/ml dosage of metformin and catechin demonstrated higher enzyme inhibition compared to the separate treatments. Compared to metformin and acarbose, the results of this study showed that catechin with 1hvx and 5zcb exhibited the highest binding affinity interaction via hydrogen bonding and pi-interaction. Conclusion: The study's findings showed that when compared to metformin and acarbose, catechin with 1hvx and 5zcb showed the highest binding affinity relationship via hydrogen bonding and pi-interaction. Higher levels of enzyme inhibition were seen when metformin and catechin were administered together than when either medication was taken alone. Based on the aforementioned report, we deduced that metformin and catechin together had more potent antidiabetic actions in vitro. We can conclude that catechin, in combination with metformin, may be developed into a possible oral hypoglycemic drug. High-affinity capacity catechin was found to have a strong inhibitory effect on α-glucosidase and α-amylase. The possible interaction pathways between these main inhibitors and two digestive enzymes were identified by docking studies. This study demonstrates the efficaciousness of catechin in preventing and treating posthyperglycemia. This work suggests interesting directions for future research and clinical applications by endorsing the use of these phytocompounds as powerful anti-diabetic pharmaceuticals, either as single compounds or in combination with synthetic drugs.