Scientists at the Salk Institute's Molecular Neurobiology Laboratory have discovered a way to activate mammalian brain cells using ultrasound alone. In this way it is possible to obtain a deep brain stimulation even without implants and wires.
This gives hope that sonogenetics can treat and cure ailments such as Parkinson, which prevents the mobility of patients by gradually making daily movements more difficult.
The future is wireless
The method used today took its first steps in 1989: it is called deep brain stimulation. It is a technique that (among other things) can generate impulses that can control the abnormal electrical signals due to Parkinson's. However, it requires the implantation of a device into the patients' heads.
The technique of using ultrasound waves to excite groups of genetically identified cells is known as "sonogenetics", a term created and popularized by prof. Sreekant Chalasani more than a decade ago.
The study of sonogenetics
In the recent study, the team discovered a new protein, TRPA1, known to allow cells to react to harmful chemicals and activate different types of human cells, including those of the brain and heart. This channel was found opened by ultrasound in a standard human research cell line (HEK).
To advance the study, a gene therapy approach was used to deliver human TRPA1 protein genes to a group of neurons in the brains of mice. It turned out that only neurons with TRPA1 genes were activated with ultrasound.
With further research, sonogenetics may be able to cure Parkinson's without any need for brain implants.
The next steps
Although we now know that TRPA1's function is to detect temperature changes, not cause them, this study shows how temperature changes can be critical for some types of cancer cells.Corinne Lee-Kubli, lead co-author of the paper.
Sonogenetics can also be used to treat other conditions, however.
First, those that limit mobility, such as epilepsy, allowing doctors to activate brain cells in a particular area without the need for surgery. In future developments, it could even replace a pacemaker by activating and regulating heart cells.