Stephen Kintz
Oct 30, 2011

Growing synapses by the hundreds

Synapses are the connections between neurons that allow neurons to communicate with either an electrical or chemical signal. There are about one hundred billion neurons, and each neuron has several thousand connections. It is estimated that the adult brain has one hundred to five hundred trillion synapses. So it is understandable that several nasty neurodegenerative diseases, like Alzheimer, have been found to target and destroy synapses. This makes it important for researchers to be able to grow and study synapses within the laboratory.


Researchers, Peng Shi and colleagues, at MIT have developed new synapse microarray technology that could potentially be used to test new treatments for strengthening the synaptic connections between neurons. The researchers, who published an article on their new technology in “Nature Communication” on October 25, 2011, claim that their new microarray technology is ten times more sensitive than current synapse microarrays and a magnitude faster at growing synapses [1, 2].


While researchers could already grow synapses in lab dishes, these lab dishes usually create a jungle of neurons and synapses. This makes it difficult for researchers to use these arrays to test potential treatments. The new synapse microarray technology uses two compartments and tiny micro-channels. Neurons are placed in one compartment, and synapses are induced to grow through the tiny micro-channels and into the second compartment. This allows the researchers to grow hundreds of thousands of synapses in an organized and more readily studied manner.


This new method of growing synapses is far more advanced than current methods. More importantly, this new synapse microarray will allow other researchers to test new drugs for strengthening synaptic connections quicker and easier than older methods. This will, hopefully, lead to new treatments for neurodegenerative diseases, like Alzheimer. In fact, to demonstrate the possibilities of the new synapse microarray technology, Peng Shi and colleagues have already used the synapse microarray technology to test several histone deacetylases inhibitors.


Histone Deacetylases (HDAC) is a class of enzymes that regulate the folding of DNA. It is the folding of DNA that determines which genes are expressed or unexpressed. HDAC inhibitors are compounds that loosen HDAC and, in turn, change how the DNA is folded and expressed. The researchers at MIT discovered several new HDAC inhibitors that improve synaptogenesis and strengthen synapses by over 300 percent. Hopefully, these new HDAC inhibitors might lead to better treatments for neurodegenerative diseases.


While this new technology is only a small step to finding new treatments and farther off from finding a cure for neurodegenerative diseases, this is an exciting development. Furthermore, there is possibility that this new technology could be used to research the communication patterns between neurons, which could lead to an explosion of new insights into how the brain works.


This research, along with research done earlier this year by Matti Mintz and colleagues at Tel Aviv University in Israel, who replaced a damaged mouse cerebellum with a computer chip, have made this an exciting year for neuroscientists and brain enthusiasts.