Bamboo charcoal mitigates oxidised LDL-induced foam cell formation via molecular interaction and adsorption: Evidence from in silico and in vitro studies

Abstract

Atherosclerosis is partially driven by the accumulation of oxidised low-density lipoprotein (oxLDL), which facilitates foam cell formation and vascular inflammation. This research examines the efficacy of bamboo charcoal (BC) as a bioactive agent for neutralising oxLDL using both in silico and in vitro methodologies. Molecular docking demonstrated significant binding affinities between BC and essential constituents of oxLDL, such as oxidised cholesterol and apolipoprotein B-100, facilitated by π–π stacking and electrostatic interactions. Molecular dynamics simulations demonstrated the stability of these complexes over 300 ns, indicating sustained molecular interactions. Quantum chemical calculations employing density functional theory showed a narrow HOMO–LUMO gap of 0.45 eV and a significant dipole moment of approximately 45 D, underscoring the reactive and polar characteristics of BC. Electrostatic potential mapping and thermodynamic analyses provided additional evidence for BC's spontaneous and stable binding to oxLDL components. The Oil Red O staining and total cholesterol estimation assays were conducted on oxLDL-treated RAW 264.7 macrophages in vitro indicated that BC significantly decreased macrophage-derived foam cell formation, thereby confirming its ability to reduce oxLDL-induced lipid accumulation. The findings suggest that BC functions as a physical adsorbent and a participant in direct chemical interactions with oxLDL, providing a dual-action therapeutic approach to atherosclerosis.