Skip to main content

Profile: Maria (MariVi) Tejada-Simon

Maria Tejada-Simon
Maria Victoria (MariVi) Tejada-Simon, M.Ed., Ph.D.
Associate Professor of Pharmacology
Joint appointments: Psychology, Biology
Director, Faculty Development

Health 2
University Of Houston College of Pharmacy
4849 Calhoun Road, Room 5017
Houston, TX 77204-5037

Office: 713-743-7835
Lab: 713-743-1772


B.S. in Biology, Universidad Complutense de Madrid (Spain)
M.S., Michigan State University, E. Lansing, MI
M.Ed., University of Houston, Houston, TX
Ph.D., Michigan State University, E. Lansing, MI
Postdoctoral Fellowship, Baylor College of Medicine, Houston, TX

Research, Academic and Teaching Interests

Research Interests

  • Small GTPases in LTP, hippocampus-dependent learning and memory.
  • Implication of small GTPases in defective synaptic plasticity.
  • Rac1-dependent regulation of neuronal morphology in cognitive disabilities.
  • Therapeutic potential of small GTPase inhibition in Fragile X syndrome

Academic Interests

  • Increase undergraduate/underrepresented minorities' research interest in neuroscience
  • Educational outreach

Teaching Interests

  • Advanced Pharmacology: Antipsychotics and antidepressants
  • Neuropharmacology
  • Cellular Science: Glucose homeostasis / Complex carbohydrates / Fatty acids synthesis and degradation / Aminoacids synthesis and degradation / Gastrointestinal system function / Vitamins and trace minerals
  • Organs Systems Life Sciences (Physiology/Anatomy): Autonomic Nervous System / Central nervous system control of visceral organs


Our research is focused on elucidating the role of the small GTPase Rac in LTP and in hippocampus-dependent learning and memory. In area CA1 of the hippocampus, the most commonly studied form of LTP is dependent on the activation of NMDA receptors. Previously in our laboratory we have found that Rac is highly expressed in the adult mouse hippocampus where it is equally distributed between cytosolic and membrane fractions, indicating that this protein might be cycling between inactive and active forms. In addition, our investigation showed that NMDA receptor activation in hippocampal slices causes Rac to translocate to the membrane in a manner similar to that observed in activated phagocytic cells, and that translocation and activation of Rac occurs during associative contextual fear learning in the hippocampus of the adult animal. We are currently investigating whether Rac is an important molecule involved post-developmentally in synaptic plasticity in the adult mice, playing a role in the neuro-anatomical and cyto-architectural changes of neurons and in the activation of signal transduction pathways associated with LTP and hippocampal learning and memory.

A second aspect of our research is related to mental retardation (MR) syndromes. Precise synaptic connectivity is essential for normal brain function and the most common neuropathology associated with MR is an alteration of this connectivity due to aberrant dendritic spine morphology. Abnormalities in dendrites and spines have been associated with the impaired cognitive abilities in MR, but how they were generated is not yet well understood. It is of great interest to understand the mechanism that lead to lose of synapses and defective synaptic plasticity. In this regard, there is evidence pointing to the Rho family of small GTPases, proteins that mediate actin cytoskeleton reorganization, neuronal morphogenesis and gene expression. The role of the small GTPases-linked genes in MR could provide a connection between the mechanism and the neuronal microstructural deficits observed in these cognitive disorders. Thus, our laboratory is investigating Rac-dependent regulation of neuronal morphology in MR syndromes.

For all these studies we use a multidisciplinary approach, a combination of pharmacological, biochemical, electrophysiological and behavioral studies, coupled with the use of genetically altered mice.

Research Images

Synaptic localization of Rac in the mouse hippocampus. Fig. 2: Electron micrographs of representative sample of synaptoneurosomes isolated from mouse hippocampus. Fig. 3.: Golgi-Cox impregnated neurons from mouse hippocampus.

Lab Alumni

oderhowho-ts-lab.jpg Alexander Oderhowho
Undergraduate Student (Biology)
Research: Effect of prenatal stress exposure and NMDA receptor hypofunction in the offspring

daeun-ts-lab.jpg Daeun May Park
Pharm.D. Student
Research: Pharmacology of Small GTPase Inhibitors in Autism

quinlan-lin Quinglan Ling
Graduate Student (Pharmacology)
Research: Statin therapy in plasticity and neurodevelopmental disorders

Luis Martinez Luis Alberto Martinez, B.S. ('04), Ph.D. ('16)
Graduate Student (Pharmacology)

Nadeem Tajuddin, B.S. Medical Sciences      
University of Western Ontario
Summer 2008

Jermeece Augustine Jermeece Augustine, B.S. Biology
University of Houston
May 2008 – May 2009

Mary Elhardt Mary Elhardt, B.S. Biology and Political Science
University of Houston
May 2008 – August 2010

Emmanuel Oni, B.S. Biology and Psychology
University of Houston
May 2009 – May 2010

Karlis Butler, B.S. Pharmaceutical Sciences
University of Houston
May 2009 – July 2010

AnniePally.jpg Annie Pally, Undergraduate Student (Biochemistry/Honors College)
University of Houston
January 2011 – December 2011

tina-nguyen.jpg Tina Nguyen, Undergraduate Student (Biochemistry)
University of Houston
January 2012 – May 2012

Odelia.jpg Odelia Bongmba, Ph.D. in Pharmacology (2012)
University of Houston
September 2007 – May 2012

tri-le.jpg Tri Le
Undergraduate Student, Biology major with Chemistry and Health minors
September 2012-August 2013

stacy-nguy.jpg Stacy Nguy
Undergraduate Student - Tier One Scholar (Biochemistry)
University of Houston
September 2012-December 2013

ray-sucharit.jpg Sucharit Ray
Graduate Student (Biology) - Master's degree
University of Houston
March 2013-July 2014

lopez-tenee.jpg Tenee Lopez
Undergraduate Student - Biology
University of Houston
August 2013-May 2014

Awards & Honors

  • 2016 Faculty Excellence for Teaching, College of Pharmacy (UH)
  • 2013 Faculty Excellence in Service, College of Pharmacy (UH)
  • 2013 Faculty Award for Mentoring Undergraduate Research (UH)
  • 2013 FASEB MARC Faculty-Student Award 
  • 2012 Provost Faculty travel award
  • 2010 Finalist, Sisley-Jerome LeJeune International Award
  • 2010 FASEB-MARC Faculty-Student Award
  • 2009 Carl Storm Scholarship, Gordon Research Conferences
  • 2009 National Fragile X Foundation Travel Award
  • 2008 Judge Funding Award, Annual Biomedical Research Conference for Minority Students (ABRCMS)
  • 2008 Provost 2008-2009 Faculty Travel Award
  • 2008 MEd Associates Scholarship award
  • 2007 Academy Distinguished Educators Education Scholarship award (BCM)
  • 2007 Biotechnology Institute Fellows Program Award. The Biotechnology Institute.
  • 2006 Academy Distinguished Educators Education Award (BCM)
  • 2005 Neuroscience Scholar Award (NINDS)
  • 2004 National Institute of Neurological Disorders and Stroke (NINDS)
  • 2001 Federation of Clinical Immunology Society Educational Award
  • 2000 Methodist Hospital Foundation Grant Award, Methodist Hospital


Undergraduate courses
PCOL 3396, 4496 – Senior Research Project in Pharmacology
PCOL 3399, 4496 – Honors Thesis in Pharmacology
PharmD courses
PHAR5397 – Selected topics
PHAR 4320 – Organ System Life Science I
PHAR 4400 – Cellular Life Science I
PHAR 5403 – Pharmacology II – CNS, psychosis and antipsychotics
Graduate courses
PCOL 7362 – Neuropharmacology
PCOL 6293, 6298, 6398 – Independent Studies in Pharmacology
PCOL 6370 – Advanced Pharmacology
PCOL 6498 – Special Problems in Pharmacology
PCOL 8300, 8699 – Doctoral Dissertation
PCOL 6299, 6399, 6499 – Special Problems

Funding & Support

Current Funding
UH Bridge Funds in Pharmacology, 2016
UH Small Grants Program, 2016
Past Support
Grants to Enhance and Advance Research(GEAR), University of Houston
The Methodist Hospital Foundation
National Institute of Neurological Disorders and Stroke, NIH
College of Pharmacy, University of Houston
Jérôme LeJeune Foundation
FRAXA Research Foundation
Small Grants Program, University of Houston
National Fragile X Foundation

Selected Publications (since 2008)

Martinez LA, Tejada-Simon MV. Pharmacological Rescue of Hippocampal Fear Learning Deficits in Fragile X Syndrome. Mol Neurobiol. 2018 Jul;55(7):5951-5961. doi: 10.1007/s12035-017-0819-5. Epub 2017 Nov 11. PMID: 29128904

Martinez LA, Tejada-Simon MV. Increased Training Intensity Induces Proper Membrane Localization of Actin Remodeling Proteins in the Hippocampus Preventing Cognitive Deficits: Implications for Fragile X Syndrome. Mol Neurobiol. 2018 Jun;55(6):4529-4542. doi: 10.1007/s12035-017-0666-4. Epub 2017 Jul 8. PMID: 28688003

Tejada-Simon, M.V. (2017). Exploring novel therapies targeting autism and intellectual disability. International Virtual Conference Pharmacology and Pharmaceutical Sciences, Avid Sciences.

Martinez, L.; Tejada-Simon, M.V. (2016). Correcting memory deficits in Fragile X syndrome by targeting Rac1/PAK1 signaling. FASEB J. 30 (1 supp), 707.8

Nguy, S; Tejada-Simon, M.V. (2016). Phenotype analysis and rescue on female FVB-Fmr1 knockout mice. Frontiers in Biology, 11(1):43-52

Ling, Q.; Tejada-Simon, M.V. (2016). Statins and the brain: New perspective for old drugs. Progress in Neuropsychopharmacology and Biological Psychiatry, 66:80–86.

Martinez, L.; Tejada-Simon, M.V. (2016). Building memories in a mouse model of intellectual disability by attenuating Rac1 activity. FASEB J. (1 supp)

Oderhowho, A.; Tejada-Simon, M.V. (2015). Examining the consequences of pre-natal exposure to stress in the behavior of adult offspring. FASEB J. 29 (1 supp), 769.2

Tejada-Simon, M.V. (2015). Modulation of actin dynamics by Rac 1 to target cognitive function (invited review). J. Neurochemistry, 133 (6):767-779.

Tejada-Simon, M.V. (2014). The small GTPase Rac1 in mental retardation disorders. J. Addic.Neuropharmacol, 1:13.

Tejada-Simon, M.V. (2014). The small GTPase Rac1 in mental retardation disorders. J. Addic.Neuropharmacol. (in press).

Tejada-Simon, M.V (2014). Small GTP-binding proteins: a future for the treatment of cognitive disorders. Brain Dis. Ther., 3(1):114;1-4.

Tejada-Simon, M.V. (2013). Preparing the Future Faculty Workforce by Analyzing the Postdoctoral Research Training. Proc. IQHE 1:588-593.

Butler, K.; Martinez, L. A.; Tejada-Simon, M.V. (2013). Impaired cognitive function and reduced anxiety-related behavior in a Promyelocytic Leukemia (PML) tumor suppressor protein-deficient mouse. Genes, Brain and Behavior, 12(2):189-202.

Bongmba, O.Y.N.; Tejada-Simon, M.V. (2012). Small GTP-binding proteins as a therapeutic target for cognitive deficiencies. J. Neurol. Neurophysiol., S1:2155-9562.S1.09.

Tejada-Simon, M.V. and Bongmba, O.Y.N. (2012). Regulation of neuronal morphology and plasticity by small GTP-binding proteins: Implications for autism and mental retardation disorders. In Horizons in Neuroscience Research. Volume 8. Chapter 1. Editors: Andres Costa and Eugenio Villalba, NOVA Science Publishers, Hauppauge, NY. ISBN: 978-1-61942-757-0.

Bongmba, O.Y.N.; Martinez, L.A.; Elhardt, M.E.; Butler, K.; Tejada-Simon, M.V. (2011). Modulation of dendritic spine and synaptic function by Rac1: A possible link to Fragile X syndrome pathology. Brain Res. 1399:79-95. Corrigendum in Brain Res.1399 (2011), 79:95. Brain Research, 1423:114-115].

Martinez, L.A.; Tejada-Simon, M.V. (2011). Pharmacological inactivation of the small GTPase Rac1 impairs long-term plasticity and memory in the mouse hippocampus. Neuropharmacol., 61:305-312.

Salim, S.; Sarraj, N.; Taneja, M.; Saha, K.; Tejada-Simon, M.V.; Chugh, G. (2010). Moderate treadmill exercise prevents oxidative stress-induced anxiety-like behaviors in rats. Behav. Brain Res. 208(2):545-552.

Elhardt, M.E.; Martinez, L.A.; Tejada-Simon, M.V. (2010). Neurochemical, behavioral and architectural changes after chronic inactivation of NMDA receptors in mice . Neurosci. Let., 468(2):166-171.

Hoeffer, C.A., Tang, W., Wong, H., Santillan, A., Patterson, R.J., Martinez, L.A., Tejada-Simon, M.V., Paylor, R., Hamilton, S.L., and Klann, E. (2008). Removal of FKBP12 enhances mTOR/Raptor interactions, LTP, memory, and perseverative/repetitive behavior. Neuron, 60(5):832-845.


  • Founding member, International Prenylation Society (IPS-in progress)
  • Society for Neuroscience (SFN)
  • Society for Advancement of Chicanos & Native Americans in Science (SACNAS)
  • American Physiology Society (APS)
  • Molecular and Cellular Cognition Society (MCCS)
  • National Hispanic Science Network (NHSN)
  • Biology of Behavior Institute (BoBI)
  • American Society for Pharmacology and Experimental Therapeutics (ASPET)
  • Latina Research
  • Faculty Row
  • Sociedad Española de Neurociencia (SENC)