Regenerating damaged brain tissue paper is one of the long - sought holy Sangraal of medicine . And while the ambitious quest to uprise brand new neurons inside the brains of living patient may never come to pass on , a squad of Taiwanese researchers has just demonstrated validation - of - concept succeeder with a bright workaround : convert pre - existent cells whose social occasion is to support nerve cell into nerve cell themselves .
The proficiency , which is like in principle to converting adult cellphone into pluripotent stem cells , could open a fresh path for unprecedented regenerative therapies for dementia and traumatic brain wound – if it earn it through the many step that lie between animal experiments and human trials .
“ Our field of study is the first to prove that defined combinations of small molecules can induce the in vivo chemical reprogramming of astrocyte into operative mature neurons with electrophysiological characteristic . Importantly , these in situ - generated [ chemically induce neurons ] could functionally interact with resident neurons in the brain , ” direct authorHongkui Dengand his colleagues at Peking University Health Science Center wrote in apre - print manuscript .
instance just how complex and difficult to analyze the brainiac is , despite decades of neuroscience investigations backed by cut - edge brain imaging technology , experts are still up in armsabout whether or not the human brain iscapable of grow new neuronsonce puerility growth has terminate . On the other hand , astrocytes , a type of cell found curled well around synapses in gamy numbers throughout the genius , are grow during maturity .
“ There are 10 times more astrocyte than neurons , and while neurons die in stroke , the astrocytes around them hold out , ” Deng toldNew Scientist .
On top of their ubiquity and close association with neurons , Deng and his squad decided astrocyte are the ideal target area for conversion among allthe non - neuron cell typesbecause young one of course flock to sphere of injury and/or neuron death .
In the current study , the small-scale - molecule cocktail was continuously transfused directly into mouse forebrain for two weeks using a small drug pump . Brain samples taken eight weeks subsequently showed that a mellow percentage of the astrocytes near the blood transfusion situation had morph into the telltale nerve cell condition and began make nerve cell - specific protein . And critically , sample take from mouse that lived for one - year mail - infusion proved that the astrocyte - to - neuron conversion could last long - terminus , without retreatment .
A serial of experiments then confirmed that the CiNs could generate electric nerve impulses , or natural action potentials , that underlie nerve cell - to - neuron communication as quickly as six week after injection and form synapsis with neighboring neuron .
Though it is inconceivable to cognize what the mice ’s subjective side core were , the generator note that no tumors or other perceptible wellness issue arise .
Of of course , the prospect of adding new neurons into a human brain is mired in both pragmatic and philosophical concerns that can not presently be answered . What subtypes of neurons can these astrocyte mold ? How will their interactions with environ neurons compare with the neuron they are meant to put back ? Will itchange a affected role ’s personality or retentiveness ?
“ If it holds up it ’s dead awe-inspiring , and has a slew of potential program and exciting consequences , ” developmental neurobiologist Matthew Grub told New Scientist .
“ [ But the ] chance of this being serious is greater than the potential benefit , ” says Grubb . “ You ’d have to have passing good control over what cell you ’re programme , where they ’re going to go , and which cells they ’ll connect to . ”
[ H / T : New Scientist ]
