Novel treatment for thirst

Thirst is a major driver for drinking fluids which are essential to maintaining whole body homeostasis. Although the mechanisms for dehydration-induced thirst are well known and understood, there is relatively little data concerning thirst perception in healthy, normally hydrated, individuals. In particular, an understanding of how the perception of thirst is created in the mouth is largely unknown. Building on our characterisation of the oral mucosal pellicle- an adhered layer of salivary mucins on the oral mucosa, which maintains the normal hydrated feeling of the mouth, our recent data suggests there is an accumulation of sodium within the mucosal pellicle. We propose that accumulation of sodium affects the lubrication behaviour of the mucins so that they become more viscous and then sticky which we perceive as a dry mouth/ thirst. This accumulation of sodium occurs at a steady rate at rest as saliva has low amounts of sodium (around 10 - 50 mM) so that thirst occurs periodically even in normal hydrated subjects. Our preliminary study in patients undergoing dialysis indicated this accumulation of sodium is faster due to higher salivary levels of sodium and leads to the constant thirst perceived in this group. This project will further explore how the accumulation of sodium in the mucus layer affects mucin rheology/ tribology and thus perception of dry mouth/thirst. The role of the industrial partner is to supply chewing gums containing sodium chelators to remove sodium from the mucus layer.