Optogenetic Neuromodulation of the Urinary Bladder

Nerve stimulation and neuromodulation have become acceptable interventions for bladder dysfunction. However, electrical stimulation indiscriminately affects all types of cells and can lead to treatment failure and off-target effects. In recent years, advancement of knowledge of optogenetics provides a powerful tool to enable precise, minimally invasive neuromodulation.In this review, we introduce basic knowledge about optogenetics; discuss the progression of engineered opsins, gene-targeting methods, and light-delivery approaches; we also summarize the application of optogenetics in neuromodulation of the bladder and discuss the possible clinical translation in the future.Optogenetics offers a powerful tool to investigate the neural circuit of bladder storage and voiding and provides a promising approach for manipulating neurons and muscles. It is possible to achieve coordinated modulation of the bladder and its sphincter through a "closed-loop" system. Optogenetics neuromodulation could also be applied in urinary bladder control in the clinic in the future.