In silico docking analysis of CCL28 (C-C motif chemokine ligand 28) and astragalin as the potential inhibitor of rheumatoid arthritis [version 1; peer review: 1 approved, 1 approved with reservations]

Background: Rheumatoid arthritis is an inflammatory and chronic disease of the joints affecting 1% of the world’s population. Women are three times more likely to be affected than men. Many drugs are being used for the treatment of rheumatoid arthritis but they often have severe side effects. C-C motif chemokine ligand 28 (CCL28) recruits leukocytes and other proinflammatory factors to the site of joint inflammation. The purpose of the present research is the computational evaluation of astragalin, a natural flavonoid extracted from black tea, as an inhibitor of CCL28 by in silico docking. Methods: The three-dimensional structure of CCL28 to act as a molecular target was obtained from the Protein Data Bank (PDB ID: 6CWS). The quality of the CCL28 structure was assessed using Phyre 2 and Molecular Operating Environment (MOE) software was used for binding affinity analysis. Astragalin served as a ligand for docking and naproxen, a known drug for rheumatoid arthritis, was used as a standard for comparison. Results: In molecular docking, astragalin showed significant binding affinity with the CCL28 target molecule, with a binding energy of -5.40 kcal/mol, in comparison with naproxen which has a binding energy of -4.87 kcal/mol. Astragalin has strong binding affinity for CCL28 as compared to standard naproxen. Conclusion: This study revealed that astragalin could have the potential to serve as an inhibitor of CCL28 for the treatment of rheumatoid arthritis.