Brain related neurological disorders happen to be one of the most complex disorders and many don’t have cure. Epilepsy is one of them. The complexity of the brain just adds to the difficulty in diagnosing a particular disorder and thus also sometimes delays the treatment. But thanks to modern science we are making breakthroughs in understanding the human brain like never before.
Now with a new unique technique there is a new way to hack the brain. A technique that involves genetically engineering brain cells so that they fire in the presence of certain drugs has been used to treat epilepsy in rats, and it could soon be tested in humans. Clare Wilson of New Scientist magazine gives us more information.
Chemogenetics builds on optogenetics, which involves genetically engineering brain cells so that they fire in the presence of light. Selected neurons can then be turned on or off with the flick of a switch, but this requires implanting fibre-optic cables in the brain, which is impractical for treating human brain disorders.
In chemogenetics, however, no cables are needed because neurons are altered to fire in the presence of a certain chemical rather than light. “It’s got more potential in that you can give drugs to people more easily than you can get light into their brains,” says Dimitri Kullmann of University College London. Kullmann’s team tested the approach by using a harmless virus to deliver a gene into the brains of rats.
The gene encoded a protein that stops neurons from firing – but only in the presence of a chemical called clozapine-N-oxide (CNO). Several weeks later they injected the rats with chemicals that trigger brain seizures, to mimic epilepsy. If the rats were then given CNO, the severity of their seizures reduced significantly within 10 minutes.
Kullmann sees chemogenetic therapy benefiting people with focal epilepsy, a form of the condition that is triggered in part of the brain and then spreads. People with it can often feel when a seizure is about to come on, so at that point they could take CNO as a tablet, or by injection or nasal spray. The effect would only be temporary, Kullmann says, because the drug has a half-life of around 7 hours in humans.
We will have to wait patiently for this new method to be tested in humans and let us hope we will get positive results.