Selective vagal nerve stimulation using optogenetics

Vagal nerve stimulation (VNS) has enormous therapeutic potential as evidenced by around 200 current clinical trials assessing its therapeutic potential across multiple diseases. However, it is plagued by disabling side effects, such as cough and neck pain, and substantial variability in efficacy between subjects and within subjects over time. This is due to multiple factors, including that:

• the vagus nerve is not homogeneous – it contains both motor and sensory nerve axons
• the anatomy of the vagus nerve is not consistent between people such that electrode placement affects which axons are stimulated
• there is poor understanding of which axon groups need to be stimulated for effective therapy in different conditions.

There is an urgent need for a greater understanding of the organisation of the components of the vagus nerve to increase efficacy. We’re addressing these issues using cutting-edge optogenetic methods to specifically target efferent vagal fibres (the hardest fibre type to target electrically) in diseases, such as heart failure.