A recent study by the Biophysical Society uncovered “sweet taste” receptors in the heart that appear to play a role in modulating the heartbeat.
The receptors, identified as TAS 1R2 and TAS 1R3, were found on the surface of heart muscle cells. While they appear similar to the taste receptors found in the tongue, which help us perceive taste, the receptors in the heart and other organs of the body likely play a different role.
Researchers found that when the receptors in a human heart or a mouse heart were stimulated with aspartame, a common artificial sweetener, there was a marked increase in the “force of the heart muscle contraction and accelerated calcium handling — key processes for a healthy heartbeat,” the Biophysical Society press release stated.
Heart rate and blood pressure increase after a person consumes a meal, but previously, researchers thought this was due to a signal along the neural axis. However, the new research gives deeper insight into how this process is triggered.
“But we’re proposing a more direct consequence, where we have a spike in our blood sugar after eating a meal, and that’s binding to these sweet taste receptors on the heart muscle cells, causing a difference in the heartbeat,” said Micah Yoder, a graduate student at the Kirk lab at Loyola University Chicago Stritch School of Medicine.
The study found that the overstimulation of the heart’s “sweet taste” receptors led to an “arrhythmic-like behavior in the heart cells,” the press release stated. This may explain why the overconsumption of artificially – sweetened beverages has been linked to an irregular heartbeat.
In the past, researchers in Nigeria had identified cardiac “bitter taste” receptors, known as TAS2Rs, that played a role in “mediating inflammatory, oxidative stress responses, autophagy, impulse generation/propagation and contractile activities in the heart,” according to a study published by the National Institutes of Health in 2022.
However, the most recent study marks the first time that “sweet taste” receptors have been identified in the heart muscle. The findings of the study will be presented this week during the 69th Biophysical Society Annual Meeting in Los Angeles.
Researchers hope these findings will open new doors to understanding how the heart functions and the potential to develop new treatments for heart failure.