SuppliedUniversity of Alberta researchers have discovered several biomarkers that could help predict adverse clinical outcomes associated with long COVID-19. As well, they found one specific amino acid could also be a potential treatment for individuals with the condition.
Long COVID-19 is the persistence of symptoms following an initial COVID-19 infection. Symptoms associated with long COVID-19 can last weeks, months, or years. These symptoms contribute to an overall decrease in quality of life.
Biomarkers, detected in biological samples, indicate changes happening in the body and help detect the onset of disease. The research team, led by Dr. Gavin Oudit, a professor in the faculty of medicine and dentistry, devised a tool that identifies several biomarkers. According to Dr. Oudit, the team was able to identify a number of biomarkers that were altered in patients who had COVID-19.
Taurine could be a biomarker signature for long COVID-19, Dr. Oudit says
The study enrolled 117 patients with COVID-19 from wards and intensive care units in Alberta, and 28 healthy patients. They collected blood samples at the beginning of the study and again after six months. From these blood samples, the team looked at present biomarkers that changed in patients with acute COVID-19, Dr. Oudit explained.
“With the use of machine-learning, [we were] able to decipher 20 molecules that were very predictive of long COVID-19.”
This model was able to predict adverse clinical outcomes with 83 per cent accuracy in patients with acute COVID-19 following hospital discharge.
Taurine, an amino acid, had a particular ability to predict the development of long COVID-19.
“We were able to pick up with a panel of molecules that [taurine] could be used as a biomarker signature for long COVID-19. It provides a lot of insight into potential therapeutics for this condition,” Dr. Oudit said.
“Those that had lower taurine levels had more symptoms [associated with] long COVID-19.”
Taurine is a semi-essential amino acid that the liver produces. It is also found in protein-rich foods such as meat and fish.
“Taurine has all sorts of protective effects in the gut, the cardiovascular system, and the central nervous system,” Dr. Oudit said. “Taurine is anti-inflammatory and has a lot of membrane stabilizing properties.”
“We were able to show in this study that patients [who] maintain high taurine levels had minimal symptoms of long COVID-19. Those that had lower taurine levels had more symptoms [associated with] long COVID-19.”
Dr. Oudit stressed the need for further study on the effect of taurine on human health. While the researchers found high taurine was associated with minimal long COVID-19 symptoms, they did not prove that taurine alone causes these minimal symptoms. To do this, the researchers will need to perform a phase-three clinical trial.
“We want to try this out in both pediatric and adult patients with COVID-19 and patients with no COVID-19,” Dr. Oudit said. “We think [taurine] would have lots of beneficial effects [such as] anti-inflammatory effects. It may protect the brain, and it may also be good for the cardiovascular system.”
This discovery was unexpected, Dr. Oudit said. By conducting a phase-three clinical trial, the team plans to “do a biomarker driven approach.” They expect that “patients that have low taurine may be the ones that are responding better to taurine supplementation.”
For Dr. Oudit and his team, this discovery is an exciting prospect warranting further exploration.
“We are excited about the biological effects [of taurine] and its link to long COVID-19,” Dr. Oudit said. “I think it’s very exciting to be able to do this work here at the U of A and to engage our students in this research.”
