Using Optogenetics to Repair Nerve Damage

Optogenetics is a cutting edge science which involves the use of light to influence certain proteins. Researchers at Helmholtz Zentrum Munchen, a German research center for environmental health, were able to use optogenetics to fix a neural network in a zebrafish. The researchers specifically used an enzyme called adenylyl cyclase to produce a messenger molecule called cAMP. The adenylyl cyclase is sensitive to blue light and will produce more cAMP when hit with this light. The researchers found that zebrafish hit with this blue light showed a significant increase in neural repair as opposed to fish that did not get the light treatment.

A common Zebrafish

This science, while still in its infancy, has huge implications for people that suffer from nerve-damage related illnesses. The hope is that one day light treatment just like this can be used for people that suffer from degenerative nerve diseases such as Alzheimer's, Parkinson's and Multiple Sclerosis. The problem currently is the method in which the light can be introduced into the system. Zebrafish are translucent and are easily influenced by the light. Human skin, however, is not translucent and light cannot be directly used to cause any changes in any enzymes. Much more research and testing needs to be done to one day make this science a potentially valid cure for these diseases.

Scientists Prevent Memory Problems Caused by Sleep Deprivation

The hippocampus of a mouse glows green after the neurons are excited by cAMP trigger receptors.

     On November 18, 2014, scientists from the University of Pennsylvania found that a particular set of cells that are located in the hippocampus part of the brain may be responsible for memory issues after an extended amount of sleep loss.  Being that sleep is the most critical period of memory consolidation it has been pojected that lack of sleep may be linked to an extended amount of memory loss due to lack of sleep and memory consolidation.  Robbert Havekes is the lead author of this study conducted in the associated lab of Ted Abel, the study's senior author and Brush Family Professor of Biology in Penn;s School of Arts and Sciences.  Ultimately, Abel's lab published a study in Nature identifying the pathways of AMP and cAMP play a key role in sleep-loss associated with memory issues.  The reason why excitatory neurons were singled out was because of the importance these pathways have in transmitting signals in the brain, as well as their function rely on cAMP signaling.

     To conduct this experiment, mice were used as the test animal and were injected with a non-pathogenic virus that harbored the gene encoding receptor for the protein octopamine.  Octopamine triggers the cAMP pathway in fruit flies but is not naturally found in the brains of mice. Furthermore, after the hippocampus in mice were injected with the non-pathogenic virus, the team confirmed that the only excitatory hippocampal neurons expressed the receptor and that they could selectively increase cAMP levels in the cells that were injected with the octopamine.  Therefore, Havekes concluded that these data display that memory loss due to sleep deprivation is dependent on misregulated cAMP signaling in the excited neurons of the hippocampus.

     I found this article to be quite enticing because I typically do not obtain much sleep each night due to the urge to get extended amount of work done.  Additionally, those who attend Medical School or graduate programs typically do not obtain much sleep from the countless hours spent studying or doing homework, thus does this mean down the line that the individuals who decided to further their education result in a significant chance of lossing their memory?  A very scary thought!

Main article: http://www.sciencedaily.com/releases/2014/11/141118182458.htm