Submitted by sjotwani on Sun, 04/24/2016 - 7:01am
- Research Interests
Anesthetics, nerve regeneration and repair, nervous system development, brain machine interfacing:
- My research is focused at cellular and molecular mechanisms underlying brain development and plasticity. Specifically, I study how networks of brain cells assemble during development and are modified throughout life to form the basis for learning and memory. I also investigate how various anesthetic agents affect communications between brain cells and induce cytotoxicity. In collaboration with our German colleagues, our team was the first to develop a bionic hybrid which enabled direct dialogue between the brain cells and the electronics. This study was highlighted in Time Magazine and on the Discovery Channel. I have published over 120 papers in peer-reviewed scientific journals including Nature, Science, Neuron and the Journal of Neuroscience.
- Awards and Recognition
- I have been the recipient of many international and national awards including: Alfred P. Sloan Fellowship (USA); Parker B. Francis Fellowship (USA); Alberta Heritage Foundation for Medical Research Scholarships and Scientist Awards; Canadian Institutes for Health Research (CIHR) Investigator Award, and the Fellowship of the Royal College of Physicians of Edinburgh.
- I am also the recipient of the following recognition awards: Outstanding Scientist Award from the Asian Community in Toronto (2004); Canadian Sensation Award from South Asian Media Express Network (2012); Distinguished Achievement Award for Outstanding Contributions to Biomedical Research by Pakistan-Canada Association (2012); Outstanding Collaboration Award, Schulich School of Engineering (2012); Canadians for Global Care Award of Recognition (2015).
- Current Awarded Grants
ACHF Pediatric Pain Research Program
CIHR Synapse Formation
CIHR Neural control of respiration
NSERC Mechanisms underlying short term synaptic plasticity
Neurodevelopment, trophic factors, regeneration, neural networks, synapse formation, rhythmogenesis, in vitro cell culture, transplantation, rhythmic behaviours, neuronal excitability, brain-chip interfacing.
- Training Environment
Wali Zaidi - Laboratory Manager/Senior Technician – firstname.lastname@example.org
Jean Kawasoe – Laboratory Technician – email@example.com
- Significant Contributions
- First successful attempt to reconstruct a respiratory pattern generator in vitro. This paper was accompanied by an editorial review entitled “High Culture of Neuroscience” in Science [Syed et al., Science 250: 282-285, 1990 with News Views]. Similarly, the Medical Post (Toronto), CBC, CFCN, 2 and 7 News and Calgary Herald ran cover stories on the significance of this research. This work has been the focus of many respiratory text books and review articles, and provides direct insights into the cellular and synaptic basis of respiratory rhythm generation in both vertebrates and invertebrates.
- First successful demonstration that a single transplanted neuron restores the deficit in the respiratory behaviour by integrating into the host circuitry. This work was published in Neuron. These studies have allowed us to test the involvement of individual neurons in the control of respiratory behaviour [Syed et al., Neuron 8: 767-774, 1992 - with cover picture]. This work has also been the focus of many review articles and book chapters.
- Using soma-soma synapses between Lymnaea respiratory neurons, we have demonstrated that glial cells modulate cholinergic synaptic transmission between the paired cells. We subsequently identified a novel, glia-derived soluble acetylcholine-binding protein (AchBP), which is a naturally occurring analogue of the ligand-binding domains of nicotinic acetylcholine receptor (nAchRs). Presynaptically released Ach induces the secretion of AchBP into the synaptic cleft through the glial secretory pathway, where it regulates cholinergic transmission between neurons [Smit et al., Nature 11:261-268, 2001]. This study forged novel insights into synaptic mechanisms by which glial cells may actively regulate neuro transmission in the intact brain.
- In collaboration with the Max-Plank Institute (Münich), we are the first group to interface an artificial semi-conductor chip with an identified respiratory neuronal network. This research now opens a new avenue whereby, we would be able to interface neurons with the electronics to understand neuronal network properties. This research also has tremendous potential for developing future brain-controlled prosthetic devices. [Kaul et al., Physical Review Letters 92:038102(4), 2004]. This story made headlines around the world including the Discovery Channel, Time Magazine etc. Further development of the chip technology has since produced another seminal breakthrough in partnership with the NRC. Specifically, we have developed two novel chips [Py et al., Biotechnol. Bioeng, 107:593-600, 2010; Martinez et al., Biomed. Microdevices 12:977-985] that permit long-term patch clamp recordings from Lymnaea neurons. This breakthrough in technology development recently made headlines around the world (Globe & Mail, CBC National, Fox News, National Post and several hundred technology breakthrough media outlets – August 2010).
- We have demonstrated that synapse formation between excitatory [Hamakawa et al., J. Neurosci. 19:9306-9312, 1999; Woodin et al., J. Neurosci. 22:505-514, 2002; Munno et al., J. Neurosci. 23:4146-4155, 2003] but not inhibitory [Feng et al., J. Neurosci. 17:7839-7849, 1997] partners require trophic factors present in the brain conditioned medium. We have since identified and characterized Lymnaea Epidermal Growth Factor receptor, which also binds human EGF and TGFα to induce excitatory synapse formation between soma-soma paired cells and these effects involve activity-dependent Ca2+ oscillations [Xu et al., J. Neurosci. 29:2167-2176, 2009]. We have since extended our research to various vertebrate models exploring mechanisms of neuronal regeneration and degeneration in rat cortical neurons. [Xu et al., Mol. Brain, 6:29, 2013; Xu et al., Mol. Brain, 5:30, 2012].