Fending off a sinus infection may come down to a battle of bitter vs. sweet — that is, bitter and sweet taste receptors.
Researchers from Penn Medicine discovered that malfunctioning taste receptors can make you more prone to a nasty case of sinusitis, but that blocking sweet taste receptors in the upper airway can prevent an infection from developing, according to a new study published in Science Signaling.
That would be welcome news to the nearly 30 million Americans who suffer from chronic sinusitis and the stuffy nose, congestion and fatigue that go along with it.
Blocking a person’s sweet taste receptors allows the natural infection-fighting ability of bitter taste receptors to flourish. Bitter taste receptors are a natural, first-line defense against disease, according to the study authors. They work by releasing “small proteins called antimicrobial peptides which kill bacteria, viruses and fungi that enter the nose.”
When sweet receptors are highly activated, however, they can diminish the effect of the bitter receptors by slowing the stream of peptides that guard against invading pathogens.
The researchers also discovered that they can toggle with the activation level of sweet receptors by using specific amino acids that are naturally derived from bacteria. They noted that two types of amino acids secreted by the Staphylococcus bacteria activate a sweet taste receptor known as TR1, thus decreasing the amount of peptides.
“These amino acids, which come from Staphylococcus bacteria, block the body’s natural immune response by essentially hitting the breaks on the defensive bitter taste receptors,” said senior author Dr. Noam A. Cohen, an associate professor of Otorhinolaryngology and Director of Rhinology Research at Penn.
For the researchers, understanding how certain bacteria can influence the body’s natural disease-fighting response sheds light on potential therapies that may come about from the introduction of amino acids into the body. Specifically, they would seek to use amino acids to suppress sweet receptors and let bitter ones work properly.
“Specifically, in the future, sweet-receptor blockers, which are known and used in some food and supplement products, may be useful to block activation of T1R, which would allow the body’s normal defenses to work properly, even when high concentrations of D-amino acids are present,” said lead author Dr. Robert Lee, assistant professor of Otorhinolaryngology and Physiology at Penn.
The new study builds off previous research at Penn that first discovered the key role of taste receptors in disease prevention in a study that described taste receptors as “first line sentinels against infection in the upper airway.”
Unlocking the pivotal role of amino acids in how taste receptors function is a big leap forward for the development of therapies to treat sinus infections.
Chronic sinusitis occurs when the cavities around the nose and forehead become blocked or when excess mucus builds up, resulting in inflammation among one or more of the cavities. Allergies and physical characteristics, such as a deviated septum, can put people at risk for developing sinusitis, according to the American Academy of Allergy, Asthma and Immunology.