Scientists at Loyola University Chicago discovered that the heart possesses "sweet taste" receptors similar to those found on the tongue. The research reveals that these receptors are functional in cardiac muscle cells and may have implications for heart function and health.
The study is the first to identify specific sweet taste receptors, known as TAS1R2 and TAS1R3, on the surface of heart muscle cells. While taste receptors are traditionally associated with the tongue and our ability to perceive flavors, recent studies have shown that these receptors exist in other parts of the body, where they likely play different roles.
Researchers found that stimulating these sweet taste receptors with sweet substances can modulate the heartbeat and accelerate calcium handling in cardiac cells—key processes for maintaining a healthy heart rhythm. When they stimulated these receptors using aspartame, a common artificial sweetener, they observed an increase in the strength of cardiac muscle contraction.
"It has been shown that after eating, heart rate and blood pressure increase," said Micah Yoder, a graduate student at Loyola University Chicago. "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," he added.
"Not only are these sweet taste receptors particularly stimulated by artificial sweeteners like aspartame, but we found that overstimulation of these sweet taste receptors leads to increased arrhythmic behavior in cardiac cells," Yoder noted. This observation may explain why high consumption of artificially sweetened beverages is linked to arrhythmogenesis, or irregular heart rhythm.
The researchers discovered that these sweet taste receptors are more abundant in the hearts of patients with heart failure, suggesting a possible link to the disease. "During heart failure, the heart changes its energy landscape and prioritizes the uptake and use of glucose. Therefore, it is possible that during this energy shift, the heart must modify its nutrient detection capacity to adapt to this change," Yoder explained.
This article was written in collaboration with generative AI company Alchemiq