Highlights (pre-UMD)


Cocaine is a monoamine transport inhibitor. Current models attributing pharmacologic actions of cocaine to inhibiting the activity of the amine transporters alone failed to translate to the clinic. Cocaine inhibition of the dopamine, serotonin, and norepinephrine transporters is relatively weak, suggesting that blockade of the amine transporters alone cannot account for the actions of cocaine, especially at low doses. There is evidence for significantly more potent actions of cocaine, suggesting the existence of a high-affinity receptor(s) for the drug. Identifying and characterizing such receptors will deepen our understanding of cocaine pharmacologic actions and pave the way for therapeutic development. Here we identify a high-affinity cocaine binding site associated with BASP1 that is involved in mediating the drug’s psychotropic actions.


Cocaine exerts its stimulant effect by inhibiting dopamine reuptake leading to increased dopamine signaling. This action is thought to reflect binding of cocaine to the dopamine transporter (DAT) to inhibit its function. However, cocaine is a relatively weak inhibitor of DAT, and many DAT inhibitors do not share the behavioral actions of cocaine. We previously showed that toxic levels of cocaine induce autophagic neuronal cell death. Here, we show that subnanomolar concentrations of cocaine elicit neural autophagy in vitro and in vivo. Autophagy inhibitors reduce the locomotor stimulant effect of cocaine in mice. Cocaine-induced autophagy degrades transporters for dopamine but not serotonin in the nucleus accumbens. Autophagy inhibition impairs cocaine conditioned place preference in mice. Our findings indicate that autophagic degradation of DAT modulates behavioral actions of cocaine.


As traditional antidepressants act only after weeks/months, the discovery that ketamine, an antagonist of glutamate/N-methyl-d-aspartate (NMDA) receptors, elicits antidepressant actions in hours has been transformative. Its mechanism of action has been elusive, though enhanced mammalian target of rapamycin (mTOR) signaling is a major feature. We report a novel signaling pathway wherein NMDA receptor activation stimulates generation of nitric oxide (NO), which S-nitrosylates glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Nitrosylated GAPDH complexes with the ubiquitin-E3-ligase Siah1 and Rheb, a small G protein that activates mTOR. Siah1 degrades Rheb leading to reduced mTOR signaling, while ketamine, conversely, stabilizes Rheb that enhances mTOR signaling. Drugs selectively targeting components of this pathway may offer novel approaches to the treatment of depression.


Cocaine is one of the most abused drugs in modern society, with overdoses that are frequently lethal. Molecular mechanisms underlying its toxic actions have been obscure. The present study demonstrates that cocaine’s cellular toxicity involves a signaling cascade that utilizes the gasotransmitter nitric oxide, which leads to autophagy, a cellular modification that can cause cell death. Thus, manipulations that impair nitric oxide signaling and autophagy diminish cytotoxic actions of cocaine. By contrast, alterations of apoptosis and other nonautophagic modes of cell death are ineffective. Therapies directed toward the autophagic process may be beneficial in treating cocaine neurotoxicity.

Dr. Harraz list of publications:

Original Research:

  1. Harraz MM, Malla AP, Semenza ER, Shishikura M, Singh M, Hwang Y, Kang IG, Song YJ, Snowman AM, Cortés P, Karuppagounder SS, Dawson TM, Dawson VL, and Snyder SH. A high affinity cocaine binding site associated with the brain acid soluble protein 1. Proc Natl Acad Sci U S A. 2022 Apr 19;119(16):e2200545119. doi: 10.1073/pnas.2200545119. Epub 2022 Apr 11.

  2. Evan R. Semenza, Maged M. Harraz, Efrat Abramson, Adarsha P. Malla, Chirag Vasavda, Moataz M. Gadalla, Michael D. Kornberg, Solomon H. Snyder, Robin Roychaudhuri. D-cysteine is an endogenous regulator of neural progenitor cell dynamics in the mammalian brain. Proc Natl Acad Sci U S A. 2021 Sep 28;118(39).

  3. Harraz MM, Guha P, Kang IG, Semenza ER, Malla AP, Song YJ, Reilly L, Treisman I, Cortés P, Coggiano MA, Veeravalli V, Rais R, Tanda G, and Snyder SH. Cocaine-induced locomotor stimulation involves autophagic degradation of the dopamine transporter. Mol. Psychiatry. 2021 Jan 7;1025:47–13.

  4. Kang J, Le H, Karakus S, Malla AP, Harraz MM, Kang JU, Burnett AL, Boctor E. Real-time, functional intra-operative localization of rat cavernous nerve network using near-infrared cyanine voltage-sensitive dye imaging. Scientific Reports. 2020 Apr 20;10(1):6618.

  5. Kang J, Kadam S, Elmore J, Sullivan B, Valentine H, Malla A, Harraz MM, Rahmim A, Kang JU, Loew LM, Baumann M, Grace A, Gjedde A, Boctor EM, Wong DF. Transcranial photoacoustic imaging of NMDA-evoked focal circuit dynamics in rat hippocampus. J Neural Eng. 2020 Apr 8;17(2):025001.

  6. Kang J, Zhang HK, Kadam SD, Fedorko J, Valentine H, Malla AP, Yan P, Harraz MM, Kang JU, Rahmim A, Gjedde A, Loew LM, Wong DF, Boctor EM. Transcranial Recording of Electrophysiological Neural Activity in the Rodent Brain in vivo Using Functional Photoacoustic Imaging of Near-Infrared Voltage-Sensitive Dye. Front Neurosci. 2019;13:579.

  7. Weyemi U, Paul BD, Bhattacharya D, Malla AP, Boufraqech M, Harraz MM, Bonner WM, Snyder SH. Histone H2AX promotes neuronal health by controlling mitochondrial homeostasis. Proc Natl Acad Sci U S A. 2019;116(15):7471-7476.

  8. Fu C, Xu J, Cheng W, Rojas T, Chin AC, Snowman AM, Harraz MM, Snyder SH. Neuronal migration is mediated by inositol hexakisphosphate kinase 1 via α-actinin and focal adhesion kinase. Proc Natl Acad Sci U S A. 2017;114(8):2036-2041.

  9. Wang Y, An R, Umanah GK, Park H, Nambiar K, Eacker SM, Kim B, Bao L, Harraz MM, Chang C, Chen R, Wang JE, Kam TI, Jeong JS, Xie Z, Neifert S, Qian J, Andrabi SA, Blackshaw S, Zhu H, Song HJ, Ming G, Dawson VL, Dawson TM. A nuclease that mediates cell death induced by DNA damage and poly (ADP-ribose) polymerase-1. Science 2016. 2016;354(6308):aad6872-1-13.

  10. Guha P*, Harraz MM*, Snyder SH. Cocaine elicits autophagic cytotoxicity via a nitric oxide-GAPDH signaling cascade. Proc Natl Acad Sci U S A. 2016;2;113(5):1417-22. * Equal contribution authors.

  11. Harraz MM, Tyagi R, Cortés P, Snyder SH. Antidepressant action of ketamine via mTOR is mediated by inhibition of nitrergic Rheb degradation. Mol Psychiatry. 2016;21(3):313-9.

  12. Choi HW, Tian M, Manohar M, Harraz MM, Park SW, Schroeder FC, Snyder SH, Klessig DF. Human GAPDH Is a Target of Aspirin's Primary Metabolite Salicylic Acid and Its Derivatives. PLoS One 2015;25;10(11):e0143447.

  13. Ahmed I, Sbodio JI, Harraz MM, Tyagi R, Albacarys LK, Hubbi ME, Grima JC, Xu R, Kim S, Paul BD, Snyder SH. Huntington’s disease: Neural dysfunction linked to inositol polyphosphate multikinase. Proc Natl Acad Sci U S A. 2015;4;112(31):9751-6.

  14. Harraz MM, Xu JC, Guiberson N, Dawson TM, Dawson VL. MiR-223 regulates the differentiation of immature neurons. Mol Cell Ther 2014;2:18.

  15. Chi Z, Byrne ST, Dolinko A, Harraz MM, Kim MS, Zhong J, Chen R, Zhang J, Xu J, Chen L, Pandey A, Dawson TM, Dawson VL. Botch is a γ-glutamyl Cyclotransferase that Deglycinates and Antagonizes Notch. Cell Rep 2014;7(3):681-8.

  16. Xu R, Paul BD, Smith DR, Tyagi R, Rao F, Khan AB, Blech DJ, Vandiver MS, Harraz MM, Guha P, Ahmed I, Sen N, Gallagher M, Snyder SH. Inositol polyphosphate multikinase is a transcriptional coactivator required for immediate early gene induction. Proc Natl Acad Sci U S A 2013;110:16181-16186.

  17. Harraz MM, Eacker SM, Wang X, Dawson TM, Dawson VL. MicroRNA-223 is neuroprotective by targeting glutamate receptors. Proc Natl Acad Sci U S A 2012;109(46):18962-18967.

  18. Chi Z, Zhang J, Tokunaga A, Harraz MM, Dolinko A, Byrne ST, Blackshaw S, Gaiano N, Dawson TM, Dawson VL. Botch (NPG7) Promotes Neurogenesis by Antagonizing Notch. Dev Cell 2012;22(4):707-20.

  19. Harraz MM, Marden JJ, Zhou W, Zhang Y, Williams A, Sharov VS, Nelson K, Luo M, Paulson H, Schöneich C, Engelhardt JF. SOD1 mutations disrupt Redox-sensitive Rac Regulation of NADPH Oxidase in a Familial ALS Model. J Clin Invest 2008;118:659-670.

  20. Harraz MM, Park A, Abbott D, Zhou W, Zhang Y, Engelhardt JF. MKK6 phosphorylation regulates production of superoxide by enhancing Rac GTPase activity. Antioxid Redox Signal 2007;9:1803-1813.

  21. Marden JJ, Harraz MM, Williams AJ, Nelson K, Luo M, Paulson H, Engelhardt JF. Redox Modifier Genes in Amyotrophic Lateral Sclerosis. J Clin Invest 2007;117:2913-2919.

  22. Li Q, Harraz MM, Zhou W, Zhang LN, Ding W, Zhang Y, Eggleston T, Yeaman C, Banfi B, Engelhardt JF. Nox2 and Rac1 Regulate H2O2-Dependent Recruitment of TRAF6 to Endosomal Interleukin-1 Receptor Complexes. Mol Cell Biol 2006;26:140-154.

  23. Panopoulos A, Harraz M, Engelhardt JF, Zandi E. Iron-mediated H2O2 production as a mechanism for cell type-specific inhibition of tumor necrosis factor alpha-induced but not interleukin-1beta-induced IkappaB kinase complex/nuclear factor-kappaB activation. J Biol Chem 2005;280:2912-2923.

  24. Harraz M, Jiao C, Hanlon HD, Hartley RS, Schatteman GC. CD34- blood-derived human endothelial cell progenitors. Stem Cells 2001;19:304-312.

  25. Badr FM, El Habit OH, Harraz MM. Radioprotective effect of melatonin assessed by measuring chromosomal damage in mitotic and meiotic cells. Mutat Res 1999;444:367-372.

Review Articles

  1. Harraz MM, Dawson TM, Dawson VL. Advances in Neuronal Cell Death. Stroke 2008;39:286-288

  2. Harraz MM, Dawson TM, Dawson VL. MicroRNAs in Parkinson’s Disease. J Chem Neuroanat 2011;42:127-130.

  3. Harraz MM, Snyder SH. Nitric oxide-GAPDH transcriptional signaling mediates behavioral actions of cocaine. CNS Neurol Disord Drug Targets 2015;14(6):757-63.

  4. Harraz MM, Snyder SH. Antidepressant Actions of Ketamine Mediated by the Mechanistic Target of Rapamycin, Nitric Oxide, and Rheb. Neurotherapeutics. 2017;14(3):728-733.