Salivary extracellular vesicle-derived microRNAs are related to variances in parameters of obesity, taste and eating behaviour.

Background: Extracellular vesicles (EVs), conveyors of microRNAs, have recently been linked to obesity. As taste is a potent driver of eating behaviour and food intake, it's connection to EVs is of increasing interest. This study aimed at deciphering the salivary EV-microRNA profile in relation to taste perception and metabolic pathways of obesity.

Methods: Small RNA sequencing was performed on isolated salivary EVs of 90 participants from the Obese-Taste-Bud study. Pathway enrichment and association analyses were conducted to link identified microRNAs to taste recognition, eating behaviour, food intake and various anthropometric-, metabolic- and oral health parameter.

Results: The 626 identified microRNAs clustered into pathways related to energy regulation, obesity and diabetes, cell signaling and taste perception. The top three enriched microRNAs are miR-1246, miR-1290 and miR-148a-3p which showed significant associations with fasting blood glucose and cholesterol level, anthropometrics and blood pressure (p<0.05). Additionally, these microRNAs associate with trait eating behaviour (p<0.05). Several other microRNAs were linked to differences in taste recognition scores and are further related to parameters of glucose metabolism and periodontal health, salivary insulin level or food intake (p<0.05).

Conclusion: This study, one of the largest on salivary EVs, supports an interrelation of EV's microRNA load with metabolism, eating behaviour and taste recognition offering potential targets for obesity intervention.