Using light to restore health

Optogenetics is a relatively new biological technique that uses specialized light on  living tissue to control cells that have been genetically modified to express light-sensitive ion channels. Using a combination of techniques from optics and genetics researchers have been able to monitor and control the activities of individual cells, typically neurons (nerve cells) in living tissue — even within freely-moving animals— and to precisely measure these manipulation effects in real-time.

Groundwork for work in optogenetics was laid at the universities of Oxford, Stanford and at the University of Berlin. Using optogenetics scientists have been able to illuminate neural networks in the brains of various organisms that control behavior, sensation, and cognition, and provides researchers with incredible insight into behavior of cells.

Research is now ongoing in the use of optogenitics to treat blindness due to retinitis pigmentosa and advanced age-related macular degeneration, as well as chronic pain and host of neurological conditions such as depression, epilepsy, Parkinson’s and Alzheimer’s disease.

Optogenetics-based treatments offer many advantages over commonly used methods. For one, optogenetics allows the modulation of targeted cells compared to the drug based approach that cannot target cells specifically Optogenetics also enables a much faster response, which can amount to mere milliseconds on any given time scale, whereas drug-based methods can take minutes or even hours to present a response. Additionally, most medications have side effects, while optogenetic-based treatment has so far not reported any side effects.

While the value of optogenetics as a research method is undeniable, there are still many hurdles to overcome, such as the potential risks of converting cells into light-sensitive ones. Public acceptance of such procedures may also be difficult to obtain due to ethical concerns. Moreover, to shine light onto the deeply embedded neural system requires invasive interventions such as surgery. Lastly, our understanding of many complex disorders is still incomplete and more sustained research investment will be required to find which circuits need to be targeted for the treatment of complex human disorders.

One complex area that has the potential to be treated with optogentics is mental health disorders such as depression, anxiety and stress. While there is an urgent need to effectively diagnose and treat anxiety disorders, research progress is hindered by poor understanding of how affected patients perceive threats and execute anxiety behaviors.

Despite more than five decades of behavioral research using rodent models, the cellular mechanisms underlying anxiety are still unclear, and the clinical outcomes of these efforts have been disappointing. Researchers at the College of Health and Life Sciences in Qatar, led by Dr. Mohammad Farhan are attempting to uncover general principles that govern anxiety, and how different animals (with different needs and brains) implement anxious behavior.