Impact of SARS-CoV-2 on Human Body Organs

INTRODUCTION

SARS-CoV-2 is the pathogen responsible for COVID-19. This disease got emerged from Wuhan city in China and has been declared as the global emergency situation by WHO (of the International, 2020). This pandemic affected the economy of the world badly with about 2,101,164 confirmed cases.

STRUCTURE OF VIRUS AND ITS ENTRY IN CELL

It is a single-stranded RNA enveloped virus comprising of 4 proteins namely Spike, Envelope, Nucleo-capsid and Membrane proteins. Spike proteins cover its outer surface and are involved in attachment to the host cell receptor. SARS-CoV-2 gains entry into the cell through ACE-2 receptors (Walls et al., 2020). When these spike proteins bind to the receptors, Transmembrane serine proteases get active and mediates viral entry into the host cell and after entrance viral RNA is released into the host cell (Wang et al., 2020) and then replication and transcription of the viral genome take place. The synthesis, assemblage and packaging of viral proteins take place thereafter.

ANGIOTENSIN CONVERTING ENZYME-2

Angiotensin-Converting Enzyme-2 is a protein present on the surface of cells. It is basically involved in the cleavage of larger protein angiotensinogen into smaller subunits (Zhang, Penninger, Li, Zhong, & Slutsky, 2020).

ACE-2 is present in almost all the vital organs of the body such as the heart, lungs, kidneys, liver etc. It is normally involved in the regulation of processes such as blood pressure, wound healing and inflammation (Albini, Noonan, Pelosi, Di Guardo, & Lombardo, 2020). However, ACE2 is also present in the epithelial even if it is of nose or mouth or lungs.

Normally ACE2 breaks down angiotensin II but the virus gets control over ACE 2 receptors thus enabling Angiotensin II to cause inflammation and death of alveolar cells that occurs due to an increase in the amount of angiotensin II.

ORGANS MOST COMMONLY INFECTED BY SARS-CoV-2

The virus gets entry more frequently into the lungs through nose or mouth and get over the control of ACE2 receptors in the lungs thus causing difficulty in breathing and coughing (Robba, Battaglini, Pelosi, & Rocco, 2020).

The virus might also affect the heart as it gets over the control of ACE2 receptors of myocardial cells as well as those present in kidneys and other vital organs in the body that causes cardiac arrest and kidney failure depending on the severity of an attack of virus and taking over the control of ACE 2 receptors.

By: Zoha Khan

REFERENCES

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