{"71583":{"#nid":"71583","#data":{"type":"news","title":"Polymer with Neurotransmitter Promotes Nerve Growth","body":[{"value":"\u003Cp\u003EResearch reported December 11 in the journal \u003Cem\u003EAdvanced Materials\u003C\/em\u003E describes a potentially promising strategy for encouraging the regeneration of damaged central nervous system cells known as neurons.\u003C\/p\u003E\n\u003Cp\u003EThe technique would use a biodegradable polymer containing a chemical group that mimics the neurotransmitter acetylcholine to spur the growth of neurites, which are projections that form the connections among neurons and between neurons and other cells. The biomimetic polymers would then guide the growth of the regenerating nerve.\n\u003C\/p\u003E\n\u003Cp\u003EThere is currently no treatment for recovering human nerve function after injury to the brain or spinal cord because central nervous system neurons have a very limited capability of self-repair and regeneration. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022Regeneration in the central nervous system requires neural activity, not just neuronal growth factors alone, so we thought a neurotransmitter might send the necessary signals,\u0022 said Yadong Wang, assistant professor in the Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, and principal investigator of the study. The research was supported by Georgia Tech, the National Science Foundation and the National Institute of Biomedical Imaging and Bioengineering (NIBIB).\n\u003C\/p\u003E\n\u003Cp\u003EChemical neurotransmitters relay, amplify and modulate signals between a neuron and another cell. This new study shows that integrating neurotransmitters into biodegradable polymers results in a biomaterial that successfully promotes neurite growth, which is necessary for victims of central nervous system injury, stroke or certain neurodegenerative diseases to recover sensory, motor, cognitive or autonomic functions. \n\u003C\/p\u003E\n\u003Cp\u003EWang and graduate student Christiane Gumera developed novel biodegradable polymers with a flexible backbone that allowed neurotransmitters to be easily added as a side chain. In its current form, the polymer would be implanted via surgery to repair damaged central nerves.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022One of our ultimate goals is to create a conduit for nerve regeneration that guides the neurons to regenerate, but gradually degrades as the neurons regenerate so that it won\u0027t constrict the nerves permanently,\u0022 explained Wang. \u003C\/p\u003E\n\u003Cp\u003EFor the experiments, the researchers tested polymers with different concentrations of the acetylcholine-mimicking groups. Acetylcholine was chosen because it is known to induce neurite outgrowth and promote the formation and strengthening of synapses, or connections between neurons. They isolated ganglia nervous tissue samples, placed them on the polymers and observed new neurites extend from the ganglia.\n\u003C\/p\u003E\n\u003Cp\u003ESince these neuron extensions must traverse a growth inhibiting material in the body, Wang and Gumera tested the ability of the biomaterial to enhance the extension of sprouted neurites. More specifically, they assessed whether the ganglia sprouted at least 20 neurites and then measured neurite length and neurite length distribution with an inverted phase contrast microscope. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022We found that adding 70 percent acetylcholine to the polymer induced regenerative responses similar to laminin, a benchmark material for nerve culture,\u0022 said Wang. Seventy percent acetylcholine also led to a neurite growth rate of up to 0.7 millimeters per day, or approximately half the thickness of a compact disc.\n\u003C\/p\u003E\n\u003Cp\u003ELaminin is a natural protein present in the nervous tissues, but it dissolves in water, making it difficult to incorporate into a conduit that needs to support nerves for months. A synthetic polymer with acetylcholine functional groups, on the other hand, can be designed to be insoluble in water, according to Wang.\n\u003C\/p\u003E\n\u003Cp\u003ESince functional restoration after nerve injury requires synapse formation, the researchers also searched for the presence of synaptic vesicle proteins on the newly formed neurites. With fluorescence imaging, they found that neurons cultured on these acetylcholine polymers expressed an established neuronal marker called synaptophysin.\n\u003C\/p\u003E\n\u003Cp\u003ETo provide insights to new approaches in functional nerve regeneration, the researchers are currently investigating the mechanisms by which the neurons interact with these polymers. Since neurons that remain intact after severe injury have only a limited capacity to penetrate the scar tissue, these new findings in nerve regeneration could help compensate for the lost connections.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022This polymer and approach aren\u0027t limited to nerve regeneration though, they can probably be used for other neurodegenerative disorders as well,\u0022 added Wang.\n\u003C\/p\u003E\n\u003Cp\u003EThis work was funded by grant number R21EB008565 from the NIBIB of the National Institutes of Health (NIH). The content is solely the responsibility of the authors and does not necessarily represent the official view of the NIBIB or the NIH.\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EResearch News \u0026amp; Publications Office\u003Cbr \/\u003E\nGeorgia Institute of Technology\u003Cbr \/\u003E\n75 Fifth Street, N.W., Suite 100\u003Cbr \/\u003E\nAtlanta, Georgia  30308  USA\n\u003C\/strong\u003E\u003C\/p\u003E\n\u003Cp\u003EMedia Relations Contacts: Abby Vogel (404-385-3364); E-mail: (\u003Ca href=\u0022mailto:avogel@gatech.edu\u0022\u003Eavogel@gatech.edu\u003C\/a\u003E) or John Toon (404-894-6986); E-mail: (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E).\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003ETechnical Contact:\u003C\/strong\u003E Yadong Wang (404-385-5027); E-mail: (\u003Ca href=\u0022mailto:ywang@gatech.edu\u0022\u003Eywang@gatech.edu\u003C\/a\u003E).\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWriter:\u003Cstrong\u003E Abby Vogel\n\u003C\/strong\u003E\u003C\/strong\u003E\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Strategy encourages regeneration of damaged central nervous system cells"}],"field_summary":[{"value":"Research reported December 11 in the journal Advanced Materials describes a potentially promising strategy for encouraging the regeneration of damaged central nervous system cells known as neurons.","format":"limited_html"}],"field_summary_sentence":[{"value":"New strategy for encouraging neuron regeneration"}],"uid":"27206","created_gmt":"2007-12-11 01:00:00","changed_gmt":"2016-10-08 03:03:24","author":"Abby Vogel Robinson","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2007-12-11T00:00:00-05:00","iso_date":"2007-12-11T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"71584":{"id":"71584","type":"image","title":"Gumera and Wang","body":null,"created":"1449177386","gmt_created":"2015-12-03 21:16:26","changed":"1475894639","gmt_changed":"2016-10-08 02:43:59"},"71585":{"id":"71585","type":"image","title":"Neurite growth micrograph","body":null,"created":"1449177386","gmt_created":"2015-12-03 21:16:26","changed":"1475894639","gmt_changed":"2016-10-08 02:43:59"},"71586":{"id":"71586","type":"image","title":"Fluorescence image","body":null,"created":"1449177386","gmt_created":"2015-12-03 21:16:26","changed":"1475894639","gmt_changed":"2016-10-08 02:43:59"}},"media_ids":["71584","71585","71586"],"related_links":[{"url":"http:\/\/dx.doi.org\/10.1002\/adma.200701747","title":"Advanced Materials Article"},{"url":"http:\/\/www.bme.gatech.edu\/","title":"Wallace H. Coulter Department of Biomedical Engineering"},{"url":"http:\/\/www.bme.gatech.edu\/facultystaff\/faculty_record.php?id=57","title":"Yadong Wang"}],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"135","name":"Research"}],"keywords":[{"id":"7527","name":"acetylcholine"},{"id":"1912","name":"brain"},{"id":"521","name":"injury"},{"id":"7266","name":"nerve"},{"id":"7526","name":"nerve generation"},{"id":"7274","name":"nervous"},{"id":"7276","name":"neuron"},{"id":"2608","name":"neurotransmitter"},{"id":"1492","name":"Polymer"},{"id":"170887","name":"spine"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003EAbby Robinson\u003C\/strong\u003E\u003Cbr \/\u003EResearch News and Publications\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=avogel6\u0022\u003EContact Abby Robinson\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-385-3364\u003C\/strong\u003E","format":"limited_html"}],"email":["abby@innovate.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}