Transcriptomics on the Tip of Your Tongue:​ The contribution of salivary extra-cellular vesicles to taste-cell transcriptomics and eating behaviour in obesity.

Research Question: Can the intricate relationship between metabolic changes in obesity, alterations in taste perception, and the distribution and composition of extracellular vesicles (EVs) be unraveled? This study seeks to explore this uncharted territory by enrolling 111 subjects from the Obese Taste Bud (OTB) Study, subjecting them to both quantitative and qualitative analyses of salivary EVs. As we delve into the correlation between metabolic changes in obesity and shifts in taste perception, the focus on EVs aims to uncover their potential role as carriers of molecules, particularly microRNAs, and their influence on eating behavior. Through this exploration, we aim to contribute valuable insights into the medical prospects of EVs for targeted therapeutic and diagnostic purposes on a cellular level within the context of obesity research.

Methods: Using ÄKTA, a size- and molecular weight-based separation system, EVs were isolated from 2 ml saliva per subject. Nanosight technology and western blot analyses were performed for quantification and characterization of EVs. A standardized taste test was used to assess taste perception of study participants, while data on eating behaviour were obtained using standardized questionnaires. The study participants were extensively phenotyped for parameters such as body mass index, waist-to-hip circumference and further anthropometrics including data from bioimpedance analyses and clinically relevant parameters of obesity (e.g. blood pressure, lipid status, parameters of glucose and insulin metabolism, adipokine level in serum).

Results: The findings indicate a relationship between the EV size and markers of nutritional status (all P<0.05). Increased EV concentration is associated with lower adiponectin serum level (P=0.017). Furthermore, EV concentration correlates negatively with reduced arm (P=0.025) and calf circumferences (P=0.035), suggesting that body composition, rather than obesity per se, is related to EVs in saliva. The study successfully demonstrated the isolation of clean vesicles from saliva, confirmed by the presence of characteristic EV markers and the intriguing presence of PPARg, hinting at a possible origin EVs from fat cells.

Conclusion: These findings provide valuable insights into the intricate interplay between salivary EVs and obesity. Ongoing analyses on microRNA composition of salivary EVs might enlighten our understanding of how these particles may affect taste buds and eating behavior in obesity. These results may contribute to the development of effective interventions for obesity as burgeoning health concern.

Interessenkonflikt

The authors declare to have no conflict of interest.

Publication History

Article published online:
18 April 2024