Predicting the molecular mechanism of glucosamine in accelerating bone defect repair by stimulating osteogenic proteins

Abstract

Objectives: Bone defect is serious condition that is usually caused by traffic accident. Chitosan is a polymer developed as a scaffold to treat bone defect. However, the mechanism by which chitosan can accelerate bone growth in defect area is still unclear. This study aims to identify proteins which are crucial to the osteogenic properties of chitosan monomer using an in silico study.

Methods: Molecular docking was carried out on chitosan monomer, which are d-glucosamine and glucosamine 6-phosphate units against bone morphogenetic protein 2 (BMP-2), fibronectin, fibroblast growth factor (Fgf), and phosphate transporter (PiT) using AutoDock Vina. Ligand preparation was carried out using Chem3D version 15.0.0.106, while protein preparation was performed using AutoDockTools version 1.5.6.

Results: The results showed that glucosamine 6-phosphate had the best binding affinity with fibronectin and PiT, which was -5.7 kcal mol^-1 on both proteins, while d-glucosamine had the best binding affinity with PiT (-5.2 kcal mol^-1).

Conclusions: This study suggests that the osteogenic properties of chitosan may be due to the presence of bonds between glucosamine units and fibronectin and/or PiT. However, in vitro studies need to be done to prove this.

Keywords: bone defect; chitosan; glucosamine; molecular docking; osteogenic; traffic accident.