Bitter taste receptors in our lungs could help protect against respiratory failure, Anglia Ruskin University research finds
The type of receptors on our tongues that tell us when something tastes bitter have now been discovered in the walls of blood vessels in our lungs - and the finding could pave the way for a new treatment for patients with respiratory failure, including those with Covid-19.
Researchers at Anglia Ruskin University (ARU), working with Brown University and the Providence Veterans Affairs Medical Center in Rhode Island, US, showed that stimulating these bitter taste receptors helped to protect the lining of these blood vessels, known as the endothelium.
This could have implications for the treatment of acute respiratory distress syndrome (ARDS) - a condition that affects more than 10 per cent of patients in intensive care units worldwide and with a mortality rate of nearly 40 per cent.
It can be caused by pneumonia, major surgery, trauma, sepsis and Covid-19, and requires patients to undergo ventilation.
Patients with ARDS suffer an excessive increase in pulmonary vascular permeability. This allows proteins and liquids to enter the lung, leading to the development of pulmonary edema, often known as ‘water on the lungs’.
But the research, led by ARU’s Dr Zsuzsanna Kertesz and Dr Havovi Chichger and published in the journal Frontiers in Physiology, suggests stimulating receptors called T2Rs could provide a protective mechanism for the wall of the blood vessels, preventing barrier disruption and stopping liquids from passing through.
They used the compounds phenylthiocarbamide and denatonium – which is the most bitter substance known – to act on the bitter taste receptors T2R38 and T2R10, respectively.
Senior author Dr Chichger, associate professor in biomedical science at ARU, said: “One of the biggest issues that intensive care unit patients with Covid, trauma or bacterial infection suffer from is respiratory distress, commonly diagnosed as acute respiratory distress syndrome. This is an inability to get enough oxygen into the body because of fluid leak from blood vessels into the lung.
“In this new study, we have identified a new family of proteins in blood vessels in the lung called T2R, or bitter taste receptors. These are the same proteins found in the tongue which sense any bitter substances and tell us that they taste unpleasant. In blood vessels in the lung, we show that these bitter taste receptors are able to regulate how our blood vessels function when stressed.
“Most intriguingly, when we stimulate these proteins, we have found that they offer protection against fluid leak. These findings indicate that this new family of proteins in blood vessels could offer a new avenue of drugs to reduce fluid leak into the lung, and therefore help to treat patients with respiratory distress.”