The most complex phenomenon known to us in the universe - the human brain itself - is largely made up of neurons, some 100 billion of them. Understanding these neurons and their connections are the key to many new discoveries and valuable new findings. New research conducted at the Johannes Kepler University Linz is now expected to contribute significantly to this field.

In an effort to both study neurons as well as devise treatments for neuronal disorders, being able to switch neurons on and off in a non-invasive manner is essential. While there are several ways to do this, such as using light to regulate neurons, it mostly involves using tiny material that absorbs light, heats up, and results in stimulating nerve cells. The intensity of light required, however, is high, not always available, and may cause side effects.

Another approach is optogenetics, meaning introducing genetically modified material to form light-sensitive channels that can be harnessed to control the neurons. This approach works and has been successfully applied for the past 20 years as part of research efforts on brain neurons. The approach also played a key role in developing initial treatments to restore vision.

Jürgen Pfeffermann, MSc (JKU Institute of Biophysics; dept. head: Prof. Peter Pohl) explains: "Genetic interventions - especially in humans - have severe limits." Together with his institute colleagues, Simon Straßgschwandtner, MSc and Rohit Yadav, MSc, as well as partners at universities in Chicago and Graz, he has devised a new, supplementary approach.

Funded by the Austrian Science Fund, and as part of the "NanoCell" doctoral program (https://www.jku.at/institut-fuer-biophysik/lehre/doctoral-program-nanocell/), the three biophysicists have succeeded in controlling stimulable cells by means of light-sensitive lipids, i.e. fats. These so-called photolipids can use light to create stimuli, meaning trigger potential actions. Straßgschwandtner added: "In short: we can use lipids to trigger the nerve cells, and we can do it without any genetically modified material."

Human Applications are Plausible
The nerve cells can be both stimulated and de-stimulated. Ultraviolet light, for example, triggers a nerve cell response, while blue light inhibits the response. As the lipids are directly incorporated into the cell membrane, the neurons can be selected and controlled in a very specific way.

Rohit Yadav remarked: "This opens up a wide range of potential applications, particularly in medical diagnostics as a breakthrough to explore neuronal connections. We don't need genetically modified materials so use in humans is theoretically an option."

The innovative approach was recently published in the renowned journal "Nature Communications". Naturally, a considerable amount of research is still required before the method can be clinically applied. The three JKU researchers and their supervisor intend to continue working on their non-invasive, low impact approach to nerve research.

Click here to read the paper: https://rdcu.be/dx1Ig, opens an external URL in a new window