Scientists explain why COVID-19 impacts only some organs

Scientists explain why COVID-19 impacts only some organs

Several reports have recently been published regarding how the novel coronavirus impacts the lungs, and then can spread to other organs such as the heart, kidneys and liver.

Since the beginning of the COVID-19 pandemic, researchers have struggled to understand why the virus doesn't impact these tissues, but not other sets of organs. But a new study from Spain suggests that proteins found in the lungs act as the primary activators.

The team, from the University of Zaragoza and the Fundación Agencia Aragonesa para la Investigación y el Desarrollo, found that proteins in the lungs are triggered by the virus, which causes proteins in certain organs to activate, making them more susceptible to infection.

The virus uses a protein found on the outside of cells called angiotensin-converting enzyme 2 (ACE2) to enter and infect them.

Once inside a human cell, the viral proteins interact with those in the body, which can lead to either mild or severe effects. However, not every organ with abundant amounts of ACE2 is affected by the virus, which the researchers say must mean there is a different pathway for transmission.

For the study, published in the journal Chaos, the team considered how proteins prevalent in the lungs interact with proteins in other organs.

For proteins to interact with each other, they need to move inside the cell in a 'subdiffusive' way, similar to the way a drunkard walks down a crowded street with the crowd presenting obstacles to the drunkard.

Similarly, proteins in a cell must swerve around obstacles to interact, but some exist in the same cell or organ and others do not.

Taking this into account, the scientists developed a mathematical model which showed there are 59 proteins within the lungs acting as the primary activators for other organs. 

When the virus affects the lungs, this kicks off a chain of events that trigger changes in proteins in other organs. However, these changes just occurs in certain organ such as the heart and kidneys and not in others, such as the stomach, Daily Mail reported.