Molecular Docking Study for Analyzing the Inhibitory Effect of Anti-inflammatory Plant Compound Against Tumour Necrosis Factor (TNF-α)

Background: Rheumatoid Arthritis (RA) is an autoimmune disorder of symmetric synovial joints which is characterized by the chronic inflammation with 0.5-1% prevalence in developed countries. Presence of persistent inflammation is attributed to the major contribution of key inflammatory cytokine and tumour necrosis factor- alpha (TNF- α). Recent drug designing studies are developing TNF-α blockers to provide relief from the symptoms of the disease such as pain and inflammation. Available blockers are showing certain limitations such as it may enhance the rate of tuberculosis (TB) occurrence, lymphoma risk, cost issues and certain infections are major concern. Discussed limitations implicated a need of development of some alternative drugs which exhibit fewer side effects with low cost. Therefore, we have identified anti-inflammatory compounds in an underutilized fruit of Baccaurea sapida (B.sapida) in our previous studies. Among them quercetin have been identified as the most potent lead compound for drug designing studies of RA. Methods: In the present article, characterization of quercetin has been carried out to check its drug likeliness and molecular docking study has been carried out between TNF- α and quercetin by using AutoDock 4.2.1 software. Further, inhibitory effect of B. sapida fruit extract on RA plasma has been analysed through immunological assay ELISA. Results: Our in-silico analysis indicated that quercetin showed non carcinogenic reaction in animal model and it may also cross the membrane barrier easily. We have studied the ten different binding poses and best binding pose of TNF-α and quercetin showed -6.3 kcal/mol minimum binding energy and 23.94 μM inhibitory constant. In addition to this, ELISA indicated 2.2 down regulated expression of TNF-α in RA compared to control. Conclusion: This study may further be utilized for the drug designing studies to reduce TNF-α mediated inflammation in near future. This attempt may also enhance the utilization of this plant worldwide.