Molecular mechanism, diagnosis, and potential treatment for novel coronavirus (COVID-19): a current literature review and perspective

Abstract

Novel coronavirus disease 2019 (COVID-19) is a positive-sense single-stranded RNA virus which belongs to the Coronaviridae family. COVID-19 outbreak became evident after the severe acute respiratory syndrome coronavirus and the Middle East respiratory syndrome coronavirus in the twenty-first century as the start of the third deadly coronavirus. Currently, research is at an early stage, and the exact etiological dimensions of COVID-19 are unknown. Several candidate drugs and plasma therapy have been considered and evaluated for the treatment of severe COVID-19 patients. These include clinically available drugs such as chloroquine, hydroxychloroquine, and lopinavir/ritonavir. However, understanding the pathogenic mechanisms of this virus is critical for predicting interaction with humans. Based on recent evidence, we have summarized the current virus biology in terms of the possible understanding of the various pathophysiologies, molecular mechanisms, recent efficient diagnostics, and therapeutic approaches to control the disease. In addition, we briefly reviewed the biochemistry of leading candidates for novel therapies and their current status in clinical trials. As information from COVID-19 is evolving rapidly, this review will help the researcher to consider new insights and potential therapeutic approaches based on up-to-date knowledge. Finally, this review illustrates a list of alternative therapeutic solutions for a viral infection.

Keywords: COVID-19; Coronavirus; Diagnosis; Molecular mechanism; Therapeutic.

Fig. 1

Structure of SARS-CoV 2 (Modified from Shereen et al. 2020)

Fig. 2

Life cycle and mechanism of infection of SARS-CoV 2 in host cells. SARS-CoV 2 begins its life cycle when spike protein (S) binds to the cellular receptor ACE2. After receptor binding, the conformation change in the S protein facilitates viral envelope fusion with the cell membrane through the endosomal pathway. Then SARS-CoV 2 releases RNA. Genome RNA gets translated into viral replicase polyproteins (pp1a and 1ab) and further cleaved into small products by viral proteinases. The polymerase generates a series of subgenomic mRNAs by discontinuous transcription and finally translated into appropriate viral proteins. Viral proteins and genome RNA are subsequently assembled into virions in the ER and Golgi body and then transported via vesicles and released out of the cell. ACE2 Angiotensin-converting enzyme 2, ER Endoplasmic reticulum, ERGIC ER–Golgi intermediate compartment