Joseph Stephan, PhD
Biochemistry Discipline Coordinator
Chair of LAU Institutional Review Board
After completing my post-doctoral studies in the laboratory of Eric Kandel at Columbia University, I have recently relocated to Lebanon where I have established an independent research program at the LAU Gilbert and Rose-Marie School of Medicine. The main focus of my laboratory is the biological basis of memory and learning. In that context, we are interested in (1) the effects of exercise on memory and learning, and specifically the role that exercise factors such as lactate might play in improving cognitive abilities and (2) the biological roles of physiological prions: these proteins, identified initially in the context of diseases such as Creutzfeldt–Jakob and Kuru, appear to play a wide variety of roles in different physiological contexts such as long-term memory storage (and cancer). Using mouse models, neuronal cultures and the powerful biochemical and molecular arsenal of the budding yeast, S. cerevisiae, we attempt to investigate these two main questions.
- Khalifeh M, Hobeika R, El Hayek L, Saad J, Eid F, El-Khoury R, Ghayad LM, Jabre V, Nasrallah P, Barmo N, Stephan JS, Khnayzer R, Khalil C, Sleiman SF (2020). Nicotine induces resilience to chronic social defeat stress in a mouse model of water pipe tobacco exposure by activating BDNF signaling. Behav Brain Res. 2020 Mar 16;382:112499. doi: 10.1016/j.bbr.2020.112499. Epub 2020 Jan 21.
- Stephan JS, Sleiman SF (2019). Exercise factors as potential mediators of cognitive rehabilitation following traumatic brain injury. Curr Opin Neurol. 2019 Dec;32(6):808-814.
- Nasrallah P, Haidar EA, Stephan JS, El Hayek L, Karnib N, Khalifeh M, Barmo N, Jabre V, Houbeika R, Ghanem A, Nasser J, Zeeni N, Bassil M, Sleiman SF (2019). Branched-chain amino acids mediate resilience to chronic social defeat stress by activating BDNF/TRKB signaling. Neurobiol Stress. May 14;11:100170. doi: 10.1016/j.ynstr.2019.100170. eCollection 2019 Nov.
- El Hayek L, Khalifeh M, Zibara V, Abi Assaad R, Emmanuel N, Karnib N, El-Ghandour R, Nasrallah P, Bilen M, Ibrahim P, Younes J, Abou Haidar E, Barmo N, Jabre V, Stephan JS, Sleiman SF. (2019) Lactate mediates the effects of exercise on learning and memory through SIRT1-dependent activation of hippocampal Brain-Derived Neurotrophic Factor (BDNF). J Neurosci. 2019 Mar 27;39(13):2369-2382. Epub Jan 28.
- Stephan J.S., Fioriti L., Lamba N., Colnaghi L., Karl K., Derkatch I.L. and Kandel E.R. (2015) The CPEB3 protein is a functional prion that interacts with the actin cytoskeleton. Cell Reports. 2015 Jun 23;11(11):1772-85.
- Fioriti L., Myers C., Huang Y.Y., Li X., Stephan J.S., Trifilieff P., Kosmidis S., Drisaldi B., Pavlopoulos E., Kandel E.R. (2015) The Persistence of nemory and its reconsolidation require CPEB3-mediated protein synthesis in the hippocampus. Neuron. Jun 17;86(6):1433-48.)
- Stephan, J. S., Yeh, Y.Y., Ramachandran, V., Deminoff, S. J., Herman, P. K. (2010) The Tor and cAMP-dependent protein kinase signaling pathways coordinately control autophagy in Saccharomyces cerevisiae. Autophagy 6(2): 294-295.
- Stephan, J. S., Yeh, Y.Y., Ramachandran, V., Deminoff, S. J., Herman, P. K. (2009) The Tor and PKA signaling pathways independently target the Atg1/Atg13 protein kinase complex to control autophagy. Proceedings of the National Academy of Science, 106(40), 17049-54.
- Stephan, J. S. and Herman, P. K. (2006) The regulation of autophagy in eukaryotic cells: Do all roads pass through Atg1? Autophagy, 2:2, 146-148.
- Budovskaya, Y. V., Stephan, J. S., Deminoff, S. J., Herman, P. K. (2005) An evolutionary proteomics approach identifies novel substrates of the cAMP-dependent protein kinase. Proceedings of the National Academy of Science 102: 13933-13938.
Professional and Research Interests
- Molecular biology
- Yeast microbiology and genetics
- Effect of exercise on memory and learning
- Cancer and autophagy
- Neurodegenerative diseases and neuroscience
- Long-term memory maintenance
- Signaling pathways regulating cell growth and quiescence
- Kinase target identification
- Functional prions
- Ethical Conduct of Research involving human participants, patient protection, data confidentiality
Education and Training
- B.S. in Biology, American University of Beirut, Beirut, Lebanon, 1995-1999
- Master of Science in Anatomy and Cell Biology, Universite de Sherbrooke, Sherbrooke, Quebec, Canada, 2000 - 2002
- Ph.D. in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, Ohio, U.S.A., 2002 - 2008
- Masters Student Researcher, Department of Anatomy and Cell Biology, Universite de Sherbrooke, Quebec, 2000 - 2002
- Doctoral Student Researcher, laboratory of Dr. Paul Herman; Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, Ohio, 2002 - 2008
- Post-doctoral Researcher, laboratory of Dr. Paul Herman, Molecular Genetics Department, The Ohio State University, Columbus, Ohio, 2002 - 2008
- Fellow Research Scientist at laboratory of Dr. Eric Kandel, Howard Hughes Medical Institute and the Department of Neuroscience, Columbia University, New York, U.S.A.
Professional Memberships and Organizations
- Society for Neuroscience