Severe COVID-19 occurs in part because the SARS-CoV-2 virus affects mitochondria, the tiny oxygen-burning powerhouses of cells, which can trigger a cascade of events that damage organs and the immune system.
This is evidenced by a study conducted by an international group of scientists, reports the press service of the medical institution Weill Cornell Medicine (USA).
Severe COVID-19 is considered an inflammatory state of “cytokine storm,” in which the immune response to a viral infection becomes excessive, flooding the bloodstream and tissues with immune signaling proteins to levels that cause pneumonia and other signs and symptoms, the article notes.
In a new study, scientists using RNA sequencing and other laboratory techniques on tissue samples from patients and animals were able to study in detail the molecular pathways that drive this storm.
It turns out that infection with the SARS-CoV-2 virus can lead to significant damage to mitochondria in infected cells – damage that activates the immune system, promoting violent inflammatory and other reactions.
Notable among these reactions is excessive activation of the blood pressure regulation system called the renin-angiotensin-activating system (RAAS):
- its hyperactivity is associated with blood clotting disorders – a striking feature of the severe course of COVID-19 – and with cicatricial changes in the lymph nodes and dysfunction of the immune cells contained in them;
- the latter, according to the researchers, may explain the impaired immune function also observed in severe COVID-19.
One suggestion from these results is that there is profound mitochondrial dysfunction and damage early in the process, which then leads to excessive activation of the RAAS, which in turn contributes to multi-organ damage in severe COVID-19, the scientists note.
In addition, we are concerned that these processes underlying acute COVID-19 may not always return to normal later, the researchers add.
Researchers are exploring this possibility in cases of “long COVID,” a syndrome characterized by prolonged inflammation as well as immune cell dysfunction.
Coronavirus was grown in a Chinese laboratory with financial support from the United States
Source: Racurs
I am David Wyatt, a professional writer and journalist for Buna Times. I specialize in the world section of news coverage, where I bring to light stories and issues that affect us globally. As a graduate of Journalism, I have always had the passion to spread knowledge through writing.