Abstract

The pandemic infection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been rapidly increasing the number of patients afflicted with coronavirus disease 2019 (COVID-19) since December 2019. It has been reported that the entry receptor for SARS-CoV-2 is unequivocally Angiotensin- Converting Enzyme 2 (ACE2). However, it remains an open question whether ACE-related inhibitors or drugs can modify ACE2 activity and affect the viral activity and disease severity of SARS-CoV-2. This study was undertaken to determine the most promising binding receptor DPP4 with ACE2 to counteract its interaction with SARS-CoV-2 viral infection. To achieve this, Insilco studies were conducted based on retrieved data from various online databases. Molecular docking analyses have demonstrated that the spike protein Receptor Binding Domain (S-RBD) of SARS-CoV-2 efficiently binds to the DPP4 receptor, especially to the S-RBD vital residues of the RBP-binding motif located in the DPP4 receptor. Consequently, DPP4 may play a crucial role in elucidating the common pre- and post-COVID-19 symptoms of unknown etiology. This study also investigated the potential of epicatechin as a potent natural inhibitor that can be utilized to block or at least weaken the SARS-CoV-2 entry and its subsequent invasion. However, in vitro experiments are necessary to validate the effectiveness of epicatechin against the activity of the human ACE2 receptor.

Keywords: COVID-19; SARS-CoV-2; DPP4; ACE2; Spike protein; S-RBD