It’s called optogenetics: it’s a new discipline that wants to study and intervene
on the brain thanks to genetics and optical techniques, to treat various diseases
Is it possible to manipulate the brain with light? And, in the future, to treat diseases such as Parkinson’s or depression, Alzheimer’s or post-traumatic stress disorders? The questions are not straightforward. They are born from a new, or rather, new scientific discipline called optogenetics: the word already indicates that it uses optical techniques (precisely light) associated with DNA manipulations, to study the most complex organ of the human body, the brain, in fact. It is necessary to go a little in order to explain what it is, because the matter is quite complex: Ofer Yizhar, an Israeli scientist from the Department of Neurobiology of the Weizmann Institute of Science in Rehovot did it at the Science Festival.
More and more research is presented that combines medicine with quantum physics. The combination may seem bizarre, but many scientists are convinced that the future of medical science will lie in it. Among these are also some researchers from the University of Washington, who have developed a method to control neural activity, perhaps usable for the creation of new techniques for the treatment of diseases such as Alzheimer, epilepsy or depression, as well as to reactivate damaged retinal cells and therefore treat blindness. The study that talks about it was published in the journal Biomedical Optics Express.
„Many brain problems are caused by unbalanced neural activity,“ explained Lih Lin, a researcher at the US university. „Manipulation of specific neurons could allow normal brain activity to be restored.“ For this reason, several methods have been developed to artificially stimulate the brain, but all of them have side effects or contraindications that have never been overcome: deep brain stimulation is used to limit Parkinson’s tremors, but this technique is highly invasive ; transcranial magnetic stimulation can act without the need for interventions, but magnetic waves affect all cells and not just the diseased ones, so hitting the target can be complicated; finally there are techniques that use light to stimulate the nervous system, but it has not yet been proven that they are safe for use on humans.
That’s why the solution found by US researchers could be the definitive one. Scientists have developed a technique based on so-called quantum dots, or nanoparticles of semiconductor materials capable of interacting with biological processes.
To test their use, the researchers tried to place some nerve cells on a thin film covered with quantum dots, so that each of them was flanked by one of the microcrystals. They then placed a light source next to the crop. So they observed that the light radiation electrically excited the nanoparticle / cell system, activating the latter in a similar way to what happens when neurons communicate inside the brain.
Being on the border usually means being the first to face the obstacles. Despite the proven success of light medicine, the fact remains that it has not yet found its rightful place within the medical system in terms of recognition by health professionals and the general public.
The challenges are scientific and financial. The world of medicine is largely controlled by the pharmaceutical industry and light does not seem to lead to lucrative or patentable treatments such as those of pharmacology.