Inhale through your nose and exhale through your mouth. It’s not just something you do in yoga class – breathing this way actually offers a powerful medical benefit that can help the body fight off viral infections.
The reason is that your nasal cavities produce the molecule nitric oxide, which chemists abbreviate NO, which increases blood flow to the lungs and increases blood oxygen levels. Breathing in through the nose delivers NO directly to the lungs, where it helps fight coronavirus infection by block coronavirus replication in the lungs. But many people who exercise or practice yoga also experience the benefits of inhale through the nose instead of the mouth. The higher oxygen saturation of the blood can give a feeling of freshness and provide greater endurance.
I am one of the three pharmacologists who won the Nobel Prize in 1998 to find out how nitric oxide is produced in the body and how it works.
The role of nitric oxide in the body
Nitric oxide is a prevalent signaling molecule that triggers many different physiological effects. It is also used clinically as a gas to selectively dilate the pulmonary arteries in neonates with pulmonary hypertension. Unlike most signaling molecules, NO is a naturally occurring gas.
NO is continuously produced by the 1,000 billion cells that form the inner wall, or endotheliumof the 100,000 miles of arteries and veins in our body, especially the lungs. endothelium-derived NO works to relax smooth muscle in the arteries to prevent high blood pressure and promote blood flow to all organs. Another vital role of NO is to prevent blood clots in normal arteries.
In addition to relaxing vascular smooth muscle, NO also relaxes the smooth muscles of the airways – trachea and bronchioles – facilitating breathing. Another type of NO-mediated smooth muscle relaxation occurs in the erectile tissue (corpora cavernosa), resulting in penile erection. In reality, NO is the main mediator of penile erection and sexual arousal. This discovery led to the development and commercialization of sildenafiltrade name Viagra, which works by enhancing the action of NO.
Other types of cells in the body, including circulating white blood cells and tissue macrophages, produce nitric oxide to antimicrobial purposes. The NO in these cells reacts with other molecules, also produced by the same cells, to form antimicrobial agents to destroy invading microorganisms, including bacteria, parasites, and viruses. As you can see, NO is a pretty amazing molecule.
Nitric oxide gas as an inhaled treatment
Since NO is a gas, it can be delivered using specialized devices as therapy to patients via inhalation. Inhaled NO is used to treat infants born with persistent pulmonary hypertensiona condition in which constricted pulmonary arteries restrict blood flow and oxygen harvest.
Inhaled NO dilates constricted pulmonary arteries and increases blood flow to the lungs. As a result, the hemoglobin in red blood cells can extract more vital oxygen and move it into the general circulation. The inhaled NO literally turned the blue babies pink and allowed them to heal and go home to mom and dad. Before the advent of inhaled NO, most of these babies died.
Inhaled NO is currently in clinical trials for the treatment of patients with COVID-19[feminine]. Researchers hope that three main actions of NO could help fight covid: dilate the pulmonary arteries and increase blood flow to the lungs, dilate the airways and increase oxygen delivery to the lungs and blood, and kill and directly inhibit the growth and spread of the coronavirus in the lungs.
How Nitric Oxide Kills Viruses
In an in vitro study performed in 2004 during the last SARS outbreak, experimental compounds that release NO increased the survival rate of nuclear-containing mammalian cells infected with SARS-CoV. This suggested that NO had a direct antiviral effect. In this study, NO significantly inhibited the replication cycle of SARS-CoV by blocking the production of viral proteins and its genetic material, RNA.
In a small clinical study in 2004, inhaled NO was effective against SARS-CoV in critically ill patients with pneumonia.
SARS CoV, which caused the 2003/2004 outbreak, shares most of its genome with SARS CoV-2, the virus responsible for COVID-19. This suggests that inhaled NO therapy may be effective in treating patients with COVID-19. In effect, several clinical trials of inhaled NO in patients with moderate to severe COVID-19, who require ventilators, are currently underway in several institutions. The hope is that inhaled NO will prove to be an effective therapy and reduce the need for ventilators and ICU beds.
The sinuses in the nasal cavity, but not the mouth, continuously produce NO. The NO produced in the nasal cavity is chemically identical to the NO used clinically by inhalation. So by inhaling through your nose, you deliver NO directly into your lungs, where it increases both airflow and blood flow and keeps microorganisms and virus particles in check.
Looking forward to the results of clinical trials with inhaled NO and the development of an effective drug vaccine against COVID-19, we need to be on our toes and train ourselves to breathe properly to maximize the inhalation of nitric oxide into our lungs. Remember to inhale through your nose; exhale through your mouth.
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