The bitter taste receptors we have on our tongues are also found in other organs, including the gut. A new study has identified two specific receptors in the large intestine that are associated with the aging process, which may help inform diet-based strategies for healthier aging.
Although they’re found mainly in the taste buds, bitter taste receptors are also found in other tissues of the body, such as the lungs and intestines. When it comes to lung-based bitter taste receptors, we’ve written about researchers exploiting these kinds of receptors to treat asthma.
Now, a new study led by the University of Rovira i Virgili (URV) in Spain has identified two specific bitter taste receptors in the intestines that may play a key role in aging, and help to develop healthy aging strategies.
Twenty-five different bitter taste-sensing type 2 receptors, abbreviated to TAS2Rs or T2Rs, have been identified in humans. Playing a role in detecting potentially toxic chemicals, their location in the mouth and outside it – in the lungs, gut, and urinary tract, for example – makes sense because the mucosal linings of these organs interface with the outside world.
Intestinal TAS2Rs were first discovered in 1996. Since then, studies have provided a deeper understanding of their role, including their regulation of metabolism. Intestinal TAS2Rs have been found to influence how the body manages energy, releases digestive hormones, and responds to plant-based dietary compounds called phenols. However, little is known about how TAS2Rs influence the metabolic changes that take place during aging.
For the present study, the researchers aimed to investigate the impact of TAS2Rs in the lining of the large intestine on the aging process. They recruited two groups of healthy men and women, one aged 20 to 50 and the other aged 50 to 80. Participants underwent a colonoscopy for the collection of samples from the lining of the large intestine; blood samples were also taken. The samples were analyzed for metabolic biomarkers that change with aging, including inflammatory markers, lipids, and hormones produced by the gastrointestinal tract (GIT).
The researchers found that two specific bitter taste receptors were the most relevant for distinguishing between the younger and older study participants. The first, TAS2R5, was associated with changes in different types of lipoproteins, such as low-density lipoproteins (LDLs), polyunsaturated fatty acids, and the inflammatory marker interleukin-6 (IL-6). TAS2R38 was associated with sphingomyelin, a type of lipid that is present in all cell membranes. It accumulates during aging and causes cellular dysfunction and the release of some inflammatory chemicals (cytokines).
“Our study shows that these two receptors may play a key role in our understanding of how we age,” said the study’s corresponding author, Anna Ardévol, PhD, a professor in URV’s Department of Biochemistry and Biotechnology and senior researcher at the Molecular Bioactivity of Foods (MoBioFood) Research Group. “And because they are found in the large intestine, we may be able to develop approaches to promote healthier aging based on their interaction with food and the microbiota of the colon.”
The study was published in the Journal of Nutritional Biochemistry.
Source: URV
