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George D Bittner

Department of Neuroscience

Cellular/molecular mechanisms of plasmalemmal repair and nerve regeneration.


Phone: 512-471-5454

Office Location
PAT 321

Postal Address
AUSTIN, TX 78712

George Bittner graduated from Duke University in 1962 where he received his AB in Chemistry, Magna Cum Laude. He entered Stanford University as an MD/Ph.D. student in 1962. He withdrew in good standing (6th in Class) from Stanford Medical School in 1966 to devote full time to research under the tutelage of Dr. Donald Kennedy (Chairman of Biological Sciences). He received his Ph.D. in Neuroscience in 1967 from Stanford University. He began his postdoctoral work in the Department of Anatomy and the Brain Research Institute at UCLA with Dr. Jose Segundo and joined the faculty at the University of Texas in 1969. Dr. Bittner has had extensive collaborations with scientists in the US. He has been a Visiting Professor at Case Western Reserve University in Cleveland and a visiting scholar at the University of Western Australia (Nedlands,Perth). He has served on many NIH and NSF panels and was Chairperson of the Neuroscience Panel for Howard Hughes and NSF Predoctoral Fellowships in1996. his research is widely known both nationally and internationally, as recognized in part by a Research Career Development Award from the National Institutes of Health, his election as a fellow of the American Association for the Advancement of Science (AAAS) in 1992. Dr. Bittner was one of four founding members of the Institute for Neuroscience at the University of Texas and served for over a decade on its Executive Committee. He is a Professor of Neurobiology and Pharmacology at the University of Texas at Austin and an adjunct Professor at the Department of Physiology/Biophysics at the University of Texas Medical Branch (UTMB) at Galveston, TX.

Research Summary:
We research cellular/molecular mechanisms of plasmalemmal repair and nerve regeneration. That is, we examine various biophysical, biochemical, or molecular mechanisms by which lesioned neurons repair lesions to their plasmalemma and regenerate axons. We are particularly interested in the role of calcium and axonal proteins in plasmalemmal repair and how such plasmlemmal repair relates to axonal regeneration. we are also interested in how polyethylene glycol (PEG) can be used to repair severed axons so that axonal continuity and function can be permanently repaired within minutes after applying PEG to rejoin severed axons. We also explore and define biochemical pathways by which neurons repair plasmalemmal damage.

J.M. Britt, J.R. Kane, C.S. Spaeth, A. Zuzek, G.L. Robinson, M.Y. Gbanaglo, C.J. Estler, E.A. Boydston, T. Schallert and G.D. Bittner. 2010. Polyethylene glycol rapidly restores axonal integrity and improves the rate of motor behavior recovery after sciatic nerve crush injury. J Neurophysiol. 104: 695-703. doi: 10.1152/jn.01051.2009. PubMed PMID: 20445038.
C.S. Spaeth, E.A. Boydston, L.A. Figard, A. Zuzek and G.D. Bittner. 2010. A model for sealing plasmalemmal damage in neurons and other eukaryotic cells. J. Neurosci. 30:15790-15800. doi: 10.1523/JNEUROSCI.4155-10.2010. PubMed PMID: 21106818.
C. Z. Yang, S. I. Yaniger, V. C. Jordan, D. Klein and G.D. Bittner. 2011. Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved. Environmental Health Perspectives 119: 989-996. doi: 10.1289/ehp.1003220. Epub 2011 Mar 2
C.S. Spaeth, J.D. Fan, E.B. Spaeth, T. Robison, R.W. Wilcott and G.D. Bittner. 2012. Neurite transection produces cytosolic oxidation which enhances plasmalemmal repair. J Neurosci Res. 90:945-954. doi: 10.1002/neu.20005. PubMed PMID: 15266646.
C.S. Spaeth, E.B. Spaeth, R.W.Wilcott, J.D.Fan, T.Robison and G.D. Bittner. 2012. Pathways for plasmalemmal repair mediated by PKA, Epac and cytosolic oxidation in rat B104 cells in vitro and rat sciatic axons ex vivo. Devel Neurol. 72:1399-1414. doi: 10.1002/dneu.20998. PubMed PMID: 22076955.
C.S. Spaeth, T.Robison, J.D.Fan and G.D. Bittner. 2012. Cellular mechanisms of plasmalemmal sealing and axonal repair by polyethylene glycol and methylene blue. J Neursosci Res. 90:955-966. doi: 10.1002/jnr.23022. PubMed PMID: 22302626.
G.D. Bittner, C.P. Keating, J. R. Kane , J.M. Britt, C.S. Spaeth,, J. D. Fan, A. Zuzek R.W. Wilcott, W. P. Thayer, J.M. Winograd, F. Gonzalez-Lima and T. Schallert . 2012. Rapid, effective and long-lasting behavioral recovery produced by microsutures, methylene blue and polyethylene glycol after complete cut of rat sciatic nerves. J Neurosci Res. 90:967-980. doi: 10.1002/jnr.23023. PubMed PMID: 22302646.
K.W. Sexton, A.C. Pollins, N. L. Cardwell, G. A. Del Corral, G. D. Bittner, R. B. Shack, L. B. Nanney, W. P. Thayer. 2012. Hydrophilic polymers enhance early functional outcomes after nerve autografting. J. Surgical Res. 177:392-400. doi: 10.1016/j.jss.2012.03.049. PubMed PMID: 22521220; PubMed Central PMCID: PMCPMC4096106.
A. Zuzek, J.D. Fan, C. S. Spaeth, G.D. Bittner. 2013. Sealing of transected neurites of rat B104 cells requires a diacylglycerol PKC-dependent pathway and a PKA-dependent pathway. Cell Molec Neurosci. 33:31-46. doi: 10.1007/s10571-012-9868-5. Epub 2012 Aug 3.
C.L. Rodriguez-Feo, K.W. Sexton, R. B. Boyer, A. C. Pollins, N. L. Cardwell, L. B. Nanney,R. B. Shack, M. A. Mikesh, C. H. McGill, C. W. Driscoll, G. D. Bittner, W. P. Thayer. 2013. Blocking the P2X7 Receptor Improves Outcomes After Axonal Fusion. J. Surgical Research. 184(1):705-13. doi: 10.1016/j.jss.2013.04.082. PubMed PMID: 23731685; PubMed Central PMCID:.
C.Z. Yang, W. Casey, M. Stoner, G.J .Kollessery, A.W. Wong and G.D. Bittner, 2014. A robotic MCF-7:WS8 cell proliferation assay to detect agonist and antagonist estrogenic activity. Toxological Sci. 137:335-349. doi: 10.1093/toxsci/kft250. PubMed PMID: 24213142; PubMed Central PMCID: PMCPMC3908721.
S.L. Myers, C.Z.Yang, G.D. Bittner, K.L. Witt, R.R. Tice, D.D. Baird. 2014. Estrogenic and Anti-Estrogenic Activity of Off –The-Shelf Hair and Skin Products. Journal of Exposure Science and Environmental Epidemiology. 25:271-277. doi: 10.1038/jes.2014.32. PubMed PMID: 24849798.
M.A.Stoner, C.Z.Yang, and G.D.Bittner. 2014. A Robotic BG1Luc Reporter Assay to Detect Estrogen Receptor Agonists. Toxicology in Vitro. 28: 916–925. . doi: 10.1016/j.tiv.2014.03.013. PubMed PMID: 24747293; PubMed Central PMCID: PMCPMC4088324
G.D.Bittner, M. A. Stoner, C. Z. Yang. 2014. Estrogenic chemicals often leach from BPA-free plastic products that are replacements for BPA-containing polycarbonate products. Environmental Health 13:41-54. doi: 10.1186/1476-069X-13-41. PubMed PMID: 24886603; PubMed Central PMCID: PMCPMC4063249.
G.D. Bittner, M.S. Denison, C. Z. Yang, M.A.Stoner, G. He. 2014. Chemicals having estrogenic activity can be released from some BPA-free, hard and clear, thermoplastic resins. Environmental Health. 13:103-121. doi: 10.1186/1476-069X-13-41. PubMed PMID: 24886603; PubMed Central PMCID: PMCPMC4063249.
D.C. Riley, G.D. Bittner, M.A. Mikesh, N.L. Cardwell, A.C. Pollins, C.L. Ghergherehchi, S.R. Bhupanapadu Sunkesula, T.N. Ha, B.T.D. Hall, A.D. Poon, M. Pyarali, R.B. Boyer, A.T. Mazal, N. Munoz, R.C. Trevino, T.Schallert, W.P. Thayer. 2015. Polyethylene glycol--fused allografts produce rapid behavioral recovery after ablating sciatic nerve segments. J Neurosci Res.<http://www.ncbi.nlm.nih.gov/pubmed/25425242> Apr;93(4):572-83. doi: 10.1002/jnr.23514. PubMed PMID: 25425242; PubMed Central PMCID: PMCPMC4329031.
G.D. Bittner, K.K. Rokkappanavar, J.D. Peduzzi. 2015. Application and implications of PEG-fusion as a novel technology to repair injured spinal cords. Neural Regeneration Research. 10:1406-1408.
G.D. Bittner, D.R. Sengelaub, R.C. Trevino, J.D. Peduzzi, M. Mikesh, C.L. Ghergherehchi, T.Schallert, W.P. Thayer. 2016. The curious ability of PEG-fusion technologies to restore lost behaviors after nerve severance. J Neurosci Res. 94: 207-230. online 3 Nov.2015. doi. 1002/jnr 23685
C. L. Ghergherehchi, G. D. Bittner, R. L. Hastings, M. Mikesh, D. C. Riley, R. C. Trevino, T. Schallert, W. P. Thayer , S. Raju Bhupanapadu Sunkesula,, T-A. N. Ha\, N. Munoz, M. Pyarali, A. Bansal, A. D. Poon, A. T. Mazal, T. A. Smith, N. S. Wong, P. J. Dunne. 2016. Effects of extracellular calcium and surgical techniques on restoration of axonal continuity by PEG-fusion following complete cut- or crush-severance of rat sciatic nerves. J Neurosci Res. 94:231-245. Doi. 10.1002/jnr23704.
G.D. Bittner, M. Mikesh, C. L. Ghergherehchi. 2016. PEG-fusion retards Wallerian degeneration and rapidly restores behaviors lost after nerve severance. Neural Regen. Res. 11:217-219. Doi 10.4103/1673-5374.177716.
C.H. McGill, S. R. Bhupanapadu Sunkesula, A.D. Poon, M. Mikesh, G. D. Bittner. 2016. Sealing Frequency of B104 Cells Declines Exponentially with Decreasing Transection Distance from the Axon Hillock. Exp. Neurol. 279:149-158. doi:10.1016/j.expneurol.2016.02.001.
George D. Bittner, Christopher S. Spaeth, Andrew D. Poon, Zachary S. Burgess, Christopher H. McGill. 2016. Repair of traumatic plasmalemmal damage to neurons and other eukaryotic cells. Neu. Regen. Res. 11:1033-1042. doi: 10.4103/1673-5374.187019.
G.D. Bittner, D.R. Sengelaub, R.C. Trevino, C.L. Ghergherehchi, M. Mikesh. 2017. Robinson and Madison have published no data on whether polyethylene glycol fusion repair prevents reinnervation accuracy in rat peripheral nerve. J Neurosci Res. 95:863-866. doi: 10.1002/jnr.23849.
GD Bittner, DL Sengelaub, CL Ghergherehchi. 2018. Conundrums and confusions regarding how PEG-fusion produces excellent behavioral recovery after peripheral nerve injuries. Neural Regeneration Research. 13: 53-57. doi: 10.4103/1673-5374.224363.
Andrew D. Poon, Sarah H. McGill, Solomon Raju Bhupanapadu Sunkesula, Zachary S. Burgess, Patrick J. Dunne, Edward E. Kang and George D Bittner. 2019. CaMKII and DMSO affect the sealing frequencies of transected hippocampal neurons. J. Neurosci. Res. 96:1208-1222. doi: 10.1002/jnr.24232.
Mikesh M, Ghergherehchi CL, Hastings RL, Ali A, Rahesh S, Jagannath K, Sengelaub DR, Trevino RC, Jackson DM, Bittner GD. 2018. Polyethylene glycol solutions rapidly restore and maintain axonal continuity, neuromuscular structures and behaviors lost after sciatic nerve transections in female rats. J. Neurosci. Res. 96: 1223-1242. doi: 10.1002/jnr.24225.
Mikesh M, Ghergherehchi CL, Rahesh S, Jagannath K, Ali A, Sengelaub DR, Trevino RC, Jackson DM, Tucker HO, Bittner GD. 2018. Polyethylene glycol treated allografts not tissue matched nor immunosuppressed rapidly repair sciatic nerve gaps, maintain neuromuscular functions, and restore voluntary behaviors in female rats. J. Neurosci. Res. 96:1243- 1264. doi: 10.1002/jnr.24227.
Ghergherehchi CL, Mikesh M, Sengelaub DR, Jackson DM, Smith T, Shores JT, Bittner GD. (2019) Polyethylene glycol (PEG) and other bioactive solutions with neurorrhaphy for rapid and dramatic repair of peripheral nerve lesions by PEG-fusion. J Neurosci Methods. 314:1-12. NIHMS1518360, Publ.ID: NSM8215. Doi n1-.1016/jneumeth.2018.12.20.15
Bittner GD, Ghergherehchi CL, Mikesh M. 2019 Surgical Technique and Other Protocols Used Probably Did Not Induce Polyethylene Glycol Fusion of Rat Facial Nerves. JAMA Facial Plast Surg. ;21(1):81. doi:10.1001/jamafacial.2018.1126
Vargas SA and Bittner GD. 2019. Natural mechanisms and artificial PEG-induced mechanism that repair traumatic damage to the plasmalemma in eukaryotes. Current Topics in Membranes: Plasma Membrane Repair. 84: 129-167.
Ghergherehchi CL, Sengelaub DR, Mikesh M, Shores JT, Bittner GD. 2019. Alterations in spinal connectivity and remodeling of motoneuron dendritic morphology after sciatic nerve transection with polyethylene glycol axon fusion repair. PLOS One. 14(10): 1-27 e0223443. https://doi.org/10.1371/journal.pone.0223443.
Bittner G, Ghergherehchi C, Mikesh M, Senglelaub D, Trevino R, Shores J. 2019. Salomone et al did not induce PEG-fusion repair of severed rat facial nerves. Head Neck. 2019 Oct;41(10):3737-3739. doi: 10.1002/hed.25894. Epub 2019 Aug 9. PMID:31400039.
Smith TA, Ghergherehchi CL, Mikesh M, Shores JT, Tucker HO, Bittner GD. 2020. Polyethylene glycol-fusion repair of sciatic allografts in female rats achieve immunotolerance via attenuated innate and adaptive responses. J Neurosci. Res. 98:2468-2495
Smith TA Ghergherehchi CL, Tucker HO, G. D. Bittner GD.. 2020. Coding transcriptome analyses reveal altered functions underlying immunotolerance of PEG-fused rat sciatic nerve allografts. J. Neuroinflammation. doi.org/10.1186/s12974-020-01953-8
Ghergherehchi CL, Shores JT, Alderete J, Weitzel EK, Bittner GD. 2021. Methylene blue enhances PEG-fusion repair of completely severed rat sciatic nerves. Neural Regeneration Research. doi.org/10.1186/s12974-020-01953-8
Kelly C. S. Roballo, Jason P. Gigley, Tyler A. Smith, George D. Bittner, Jared S. Bushman.2021. Morphological, Functional, and Immunological Peculiarities of Peripheral Nerve Allografts. Nerve Regeneration Research. In Press

In Preparation
George D. Bittner, Jared S. Bushman, Cameron L. Ghergherehchi, Kelly C.S. Roballo, Jamie T. Shores, Tyler A. Smith. 2021. Typical and Atypical Properties of Peripheral Nerve Allografts Enable Novel Strategies to Repair Segmental Loss Injuries In pre-submission approval for Progress in Neurobiology
Tyler A. Smith, Cameron L. Ghergherehchi, Kelly C.S. Roballo, Michelle Mikesh, Haley O. Tucker, Jared A. Bushman, George D. Bittner. Polyethylene glycol treatment of peripheral nerve allografts without axonal fusion diminishes T cell infiltration and MHC expression, but does not prevent Wallerian degeneration-associated cellular responses J. Neuroinflammation. May 2021 submission
Tyler A. Smith, Cameron L. Ghergherehchi, Kelly C.S. Roballo, Michelle Mikesh, Haley O. Tucker, Jaime T Shores, Joseph Alderete, Erik K. Weitzel, Jared A. Bushman, George D. Bittner. 2022 Immunotolerance of polyethylene glycol-fused sciatic allografts from Brown-Norway rats into Lewis host rats. Frontiers in Cellular Neuroscience. October 2021v Submission