A researcher holds a tube with the coronavirus virus. Photo / Getty Images
A researcher holds a tube with the coronavirus virus. Photo / Getty Images
Editorial
EDITORIAL
The report that more than 100 life-saving ventilators have arrived in New Zealand and another 200 will land by the end of the year is reassuring.
However, possibly even more welcome is promising news in treating the worst of the symptoms, with researchers edging closer to identifying what triggersthem.
New Scientist reports an out-of-control human peptide or chain of amino acids called bradykinin could be causing some of the varied, and at times deadly, symptoms found in those who have contracted the coronavirus.
The good news is, we already have drugs to control bradykinin, and these are being tested to treat people with Covid-19.
Bradykinin helps to regulate blood pressure, and in some, the coronavirus seems to be pushing bradykinin production into overdrive. This whips up a kind of "bradykinin storm" which may lead to symptoms common in Covid-19 - such as muscle pain, women sometimes affected milder than men, and some ethnicities being more likely to suffer complications.
"This is one of those rare times where you can really tie everything back to a eureka moment," Daniel Jacobson, staff scientist in ORNL's Biosciences Division, told Science Daily.
The bradykinin hypothesis could also explain Covid-19's neurological effects, some of the more concerning elements of the disease, such as dizziness, seizures, delirium, and stroke which occur in about half of hospitalised Covid-19 patients.
It's been noted Covid-19 may be causing the same effects hypertensive patients can suffer when on blood pressure–lowering drugs. ACE inhibitors are known to cause a dry cough and fatigue, two classic Covid-19 manifestations. They can also increase blood potassium levels, another thing observed in Covid-19 patients. Researchers say the similarities between ACE inhibitor side effects and Covid-19 symptoms reinforce the bradykinin hypothesis.
ACE inhibitors are also known to cause a loss of taste and smell.
As Jacobson and team point out, several drugs treat blood pressure, fluid and electrolyte balance and are already FDA approved. They could arguably be applied to treating Covid-19 also. Several, such as danazol, stanozolol, and ecallantide, reduce bradykinin production and could stave off a deadly bradykinin storm. Others, like icatibant, reduce bradykinin signaling and could stem its effects.
Palestinian doctors treat patients at the al-Quds Hospital in Gaza City. AP Photo / Khalil Hamra
Another candidate with exciting potential is vitamin D.
The vitamin has been linked with reducing the risk of hypertension, if so it could also stop potentially deadly bradykinin storms from forming. It's a big if, but should the vitamin prove effective at reducing the severity of bradykinin storms, it might be an easy, relatively safe way to reduce the severity of the virus.
Other compounds could treat symptoms associated with bradykinin storms. Hymecromone, for one, could reduce hyaluronic acid levels, potentially stopping deadly hydrogels forming in the lungs. Timbetasin also could imitate the mechanism that researchers think protects women from more severe Covid-19 infections.
Advances are being made apace with vaccines, and much of the world attention is on trials seeking the "magic bullet". But this field is fraught with difficulty. This week there was disappointment in a promising Oxford University-led trial being suspended.
Our best chances right now may lie with progress in prevention, and treatment.
