Targeting the Tlr4–Md2 Complex with Coumarin Derivatives: Integrated In-Silico And In Vitro Evaluation of Scopoletin As A Potential Modulator of Nf-Κb Signalling in Diabetic Wound Healing
DOI:
https://doi.org/10.22159/ijap.2026v18i5.59383Keywords:
Diabetic wound, Inflammation, Macrophage polarization, TLR4-MD2Abstract
Objective: This study aims to identify and evaluate coumarin derivatives as potential TLR4-MD2 (Toll-like receptor 4 -Myeloid differentiation factor 2) antagonists for diabetic wound healing via molecular docking studies, drug-likeness and ADMET properties, and in vitro evaluation of cytotoxic, antioxidant and anti-inflammatory activities.
Methods: Molecular docking of a library of coumarin derivatives was done against the TLR4 heterodimer (PDB ID: 3FXI) with the Schrodinger suite. Seven lead compounds (scopoletin, Dicoumarol, Osthole, Esculetin, Ayapin, Umbelliferone, and Daphnetin) were picked out of docking scores and interaction profiles to continue with their evaluation. SwissADME was used to evaluate drug-likeness properties and ADMET properties. MTT assay, DPPH radical scavenging assay, nitric oxide radicalscavenging assay, albumin denaturation assay and macrophage polarization by flow cytometry were performed.
Results: Among all the compounds that were tested, scopoletin showed the highest binding specificity (−7.670 kcal/mol) in the MD2 binding pocket, which is known to have strong hydrogen bonds and hydrophobic interactions with essential residues, and scopoletinmay be effectivefor inhibition of TLR4-mediated inflammatory signalling. In vitro experiments have revealed that scopoletin was not cytotoxic till 300 µM and exhibited good antioxidant properties with 91.3% DPPH radical scavenging (IC50: 109 µmol/L). Moreover, scopoletin had concentration-dependent nitric oxide radical scavenging (31.83% to 71.4%) and protein denaturation (47.03 % to 92.47 %).
Conclusion: These results indicate that scopoletinmay be a potential agent that has massive antioxidant and anti-inflammatory effects. Targeting TLR4-MD2 axis is a feature that indicates its potential as a therapeutic candidate in improving the diabetic wound healing,warranting further mechanistic validation.
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