CEbiotech.com - Central European Biotechnology Portal
be visible on the BioBusiness market                  ISSN 2300-0228
Connection has been made!

Connection has been made!

Publish date: 2014-08-05

Brain functions remain the most fascinating but poorly understood area of human biology. Scientists from MRC laboratory in Cambridge have found a way to create and modify connections between neurons of a nematode in a highly controlled manner. Although this is just the first step, their work raises hopes for improved therapies for patients suffering from brain damage.

Tags: brain , synapse , Human Connectome Project

In his book “The Collapse of the Chaos: Discovering Simplicity in a Complex World” Ian Steward says that “If our brains were simple enough for us to understand them, we'd be so simple that we couldn't.” Even if the British mathematician is right, we might have just got one step closer to unravelling the importance of single junctions between neurons. A team led by William Schafer at the MRC Laboratory of Molecular Biology in Cambridge, UK, has just achieved what can be called a first worm neuron hack.

Nervous system of both nematode Caenorhabditis elegans which was used as a model organism and man consists of a network of interconnected neurons. The junctions between neurons, called synapses, can be divided into two types - electrical and chemical - based on the way they transmit the signal. While chemical synapses are composed of hundreds of different types of proteins, electrical ones are relatively simple – they are formed by channels linking adjacent cells, made by just one kind of protein. Neural network is a highly organized structure and which neurons form synapses is crucially important for appropriate signal propagation within the body.

Doctor Schafer’s team has found the way to introduce controlled changes into this complicated system. The scientists decided to target electrical synapses of C. elegans because of their less complicated nature. They managed to make a contact between two neurons engaged in the worm’s response to increased salt concentration which normally are not connected with each other. In a natural situation, presence of salt increases electrical activity in one of the neurons and decreases it in the other. When a junction between them was made, their responses became synchronised instead and this led to the worm being less sensitive to changes in salt concentration. The new synapse was created as a result of genetic modifications – DNA encoding the protein that builds the electrical junctions subunits was injected into the gonads of the worms. As a consequence, the protein has been expressed in some of the worms from the next generation. To control the specificity of synapse formation scientists used a mouse version of the channel protein. The gap junctions in invertebrates are composed of a different type of proteins than in vertebrates and nonmatching subunits can never form a functional channel. Thus, injecting of mammal connexin 63 under control of promoter specific for the targeted neurons ensured that no other than intended connections were made. The same system can also be used to replace already existing synapse with a different one. The team was able to introduce an electrical junction between two neurons that normally communicate by a chemical link. This time they targeted the cells responsible for the worm being able to detect chemical compounds and move in response to them. When the contact was modified, nature of the transmitted signal changed and the animals were no longer able to respond to benzaldehyde gradient.

The method published in the journal Nature Communications offers new insights into the nervous system functioning. It might answer the questions about what happens when particular synapses are damaged and how wiring patterns shape the activity of the brain. It also opens a possibility of creating of new signal paths by introducing artificially created circuits into the neural network. Modifications described by the team from Cambridge are similar to plugging and unplugging of cables in order to check their importance. The scientists believe that detailed mapping of neural connections is the first step towards new therapies. If we could redirect the signal between human brain cells, we would be able to help people whose neurons got damaged as a result of injury.

So far, experiments of Schafer’s team were focused on C. elegans, which only possess few hundreds of neurons without a centralised brain. In theory however, similar approach could be applied in higher organisms. At present, our understanding of brain is still very limited and we can learn a lot by observing even the simplest model systems. Human brain, of course, is also intensively studied. In 2009, National Institutes of Health launched the Human Connectome Project, aiming to provide a full map of anatomical and functional connections within healthy human brain. Such a detailed dataset will be an excellent baseline for studying the mechanisms of multiple dysfunctions like autism, Alzheimer’s disease and schizophrenia. The project is primarily conducted by two consortia. The first one, led by Washington University in Saint Louis and the University of Minnesota, applies imaging technologies to study human brain in parallel to conducting behavioural studies. The consortium will examine the networks of neural junctions, named connectomes, in brains of 1200 healthy volunteers, including twins and their siblings from 300 families. Data collected from 500 individuals was released in June 2014. The second consortium is led by Harvard University, Massachusetts General Hospital and University of California Los Angeles. Their studies base on the MRI imaging technology and aim to improve the resolution, quality and speed of currently available technology. Both consortia are in close collaboration and share collected data.

Undoubtedly, human brain is the most fascinating and mysterious part of our body. It is also extremely complex and as such, we might never fully understand the connection between its anatomy and function, at least not at a single synapse level. However, since neurons often work as groups, even less accurate knowledge might prove sufficient to solve some of the brains mysteries and give hope for advances in brain damage treatments.

 

Anna Oszmiana
 

Resources:

  1. Rabinowitch et al., Nature Communications 2014, 5, Article number: 4442, available at: http://www.nature.com/ncomms/2014/140716/ncomms5442/full/ncomms5442.html#compounds
  2. New Scientist: http://www.newscientist.com/article/mg22329792.300-worm-neuron-hack-to-probe-the-mysteries-of-our-brains.html#.U9kRyfldWRc
  3. http://www.humanconnectomeproject.org/
  4. http://www.humanconnectome.org/

Comments:

Add comment
Guest
2018-10-10 07:57:09 +0200
My ex left me with so much pains and since then i have been heart broken and shattered. I have contact many spell casters and they rip me off my money without any result. I have Emailed so many sites online looking for a good spell caster till i was directed by a 32years old woman who Dr Zuma has helped before, to contact Dr Zuma, i never believed him?but after i did as he directed my ex came back to me, told me to forgive her and i did and today am, spiritualherbalisthealing@gmail.com or call him +2348164728160
Guest
2016-04-03 04:56:46 +0200
My name is Jessica Luis, and I base in USA...My life is back!!! After 1 years of Broken marriage, my husband left me with two kids . I felt like my life was about to end i almost committed suicide, i was emotionally down for a very long time. Thanks to a spell caster called Dr Mohammed, which i met online. On one faithful day, as I was browsing through the internet,I came across allot of testimonies about this particular spell caster. Some people testified that he brought their Ex lover back, some testified that he restores womb,cure cancer,and other sickness, some testified that he can cast a spell to stop divorce and so on. i also come across one particular testimony,it was about a woman called Sonia,she testified about how he brought back her Ex lover in less than 2 days, and at the end of her testimony she dropped Dr Mohammed's e-mail address. After reading all these,I decided to give it a try. I contacted him via email and explained my problem to him. In just 48hours, my husband came back to me. We solved our issues, and we are even happier than before Dr Mohammed, is really a gifted man and i will not stop publishing him because he is a wonderful man... If you have a problem and you are looking for a real and genuine spell caster to solve all your problems for you. Try High monicaspiritualtemple@gmail.com anytime, he might be the answer to your problems. Here's his contact: monicaspiritualtemple@gmail.com or call him +2348134493948
Guest
2016-04-03 03:19:46 +0200
'After being in relationship with Wilson for seven years,he broke up with me, I did everything possible to bring him back but all was in vain, I wanted him back so much because of the love I have for him, I begged him with everything, I made promises but he refused. I explained my problem to someone online and she suggested that I should contact a spell caster that could help me cast a spell to bring him back but I am the type that don't believed in spell, I had no choice than to try it, I meant a spell caster called Dr Zuma zuk and I email him, and he told me there was no problem that everything will be okay before three days, that my ex will return to me before three days, he cast the spell and surprisingly in the second day, it was around 4pm. My ex called me, I was so surprised, I answered the call and all he said was that he was so sorry for everything that happened, that he wanted me to return to him, that he loves me so much. I was so happy and went to him, that was how we started living together happily again. Since then, I have made promise that anybody I know that have a relationship problem, I would be of help to such person by referring him or her to the only real and powerful spell caster who helped me with my own problem and who is different from all the fake ones out there. Anybody could need the help of the spell caster, his email: spiritualherbalisthealing@gmail.com or call him +2349055637784 you can email him if you need his assistance in your relationship or anything. CONTACT HIM NOW FOR SOLUTION TO ALL YOUR PROBLEMS'
See also
Alzheimer’s disease (AD) causes nerve tissue atrophy that appears as degenerative changes in the brain. Brain s... Read more
Tags: Alzheimer's disease , stem cells , regenerative medicine , Eva Sykova , brain , neurodegenerative disease
Brain microdialysis could revolutionize the monitoring of patients in intensive care units. Inserting the slim ... Read more
Tags: brain microdialysis , stroke , brain , brain probe , glucose