Faculty Interests Database

Faculty Affairs: Faculty Interests Database Natalia A. Riobo, Ph.D.

Biochemistry & Molecular Biology
Thomas Jefferson University
Jefferson Medical College
Assistant Professor, Dept. of Biochemistry & Molecular Biology
Mailing Address Contact Information
233 S 10th Street, BLSB 922
Philadelphia, Pennsylvania 19107
United States
Phone: 215-503-8549
Fax: 215-923-1098
Ph.D., University of Buenos Aires, 2001

Postdoctoral Fellow, American Heart Association, 2004-2006
Scientist Development Award recipient, American Heart Association, 2006-present
Member, American Heart Association
Member, International Society for Stem Cell Research
Expertise and Research Interests
My interest is to understand the role of the each pathway activated by Hedgehogs in biologically relevant processes. In particular, we have three areas of research:

1. Angiogenesis: The formation of new vessels from pre-existing ones involves coordinated proliferation, migration, and tubulogenesis of endothelial cells. Hedgehog promotes, and is required for, many types of angiogenesis. Our goals are to understand the Hedgehog signaling pathways involved in angiogenesis. A focus of this project is the crosstalk between Hedgehog signals and mitochondrial function to support endothelial cells proliferation.

2. Myocardial regeneration: Our objective is to understand the molecular mechanism/s underlying stem cell maintenance, proliferation, and specification into cardiac cell types. The regenerative potential of cardiomyocytes in vivo is very limited, leading to persistent function deficits in chronically or acutely ischemic injured hearts. Our long-term goal is to use mesenchymal stem cells (MSCs) isolated from adipose tissue to generate cardiac progenitors that can terminally differentiate into cardiomyocytes when transplanted back into the heart. To this end, MSCs will be manipulated in vitro with embryonic growth factors, with emphasis in Hedgehog, in an attempt to recapitulate embryonic cardiogenesis.

3. Cancer: hyperactivation of the Hedgehog signaling pathway is very common in human cancers. We are interested in evaluating the role of signal crosstalk between Hedgehog and other growth factors that activate PI3K/Akt and/or ERK in the control of cancer cell proliferation and survival.
Other Expertise
The Hedgehog family of ligands regulates a plethora of biological processes involved in embryonic development, tissue homeostasis and regeneration, and cancer progression. The canonical Hedgehog pathway is based on a series of de-repression events mediated by the proteins Patched, Smoothened, and Su(Fu) that allow a tightly controlled activation of the downstream transcription factors Gli1, Gli2, and Gli3. We and others have recently shown that Hedgehog, signaling through Smoothened, also activates Gi proteins/GRK2/arrestin, PI3K/Akt, and ERK signaling pathways which may have physiological significance on their own. In addition, Patched directly regulates cell cycle progression in a Hedgehog-dependent manner. These newly discovered events are grouped into the so-called non-canonical Hedgehog pathway.
Hedgehog, angiogenesis, stem cells, G proteins, phosphorylation, signal transduction, cancer, regenerative medicine, cardiovascular biology.
  • 1. JJ Poderoso, MC Carreras, C Lisdero, NA Riobo, F Schöpfer, and A Boveris. Nitric oxide inhibits electron transfer and increases superoxide radical production in rat heart mitochondria and submitochondrial particles. Arch. Biochem. Biophys. 328: 85-92 (1996).
  • 2. EM Gatto, MC Carreras, GA Pargament, NA Riobo, C Reides, M Repetto, MM Fernández Pardal, S Llesuy, and JJ Poderoso. Neutrophil function, nitric oxide and blood oxidative stress in Parkinson''s disease. Movement Disord. 11: 261-267 (1996).
  • 3. MC Carreras, NA Riobo, A Boveris and JJ Poderoso. Effects of respiratory burst inhibitors on nitric oxide production by human neutrophils. Free Radicals Res. 26: 325-331 (1997).
  • 4. JJ Poderoso, MC Carreras, FJ Schöpfer, CL Lisdero, NA Riobo, C Giulivi, A Boveris, P Evelson, A Boveris, and E Cadenas. The reaction of nitric oxide with ubiquinol; kinetic properties and biological implicances. Free Radic. Biol. & Med. 26: 925-935 (1999).
  • 5. EM Gatto, NA Riobo, MC Carreras, FJ Schöpfer, GA Pargament, and JJ Poderoso. Circulating plasma factors increase nitric oxide production by neutrophils in Parkinson''s disease. J. Neurol. Sci. 165: 66-70 (1999).
  • 6. JJ Poderoso, MC Carreras, CL Lisdero, FJ Schöpfer, NA Riobo, and J Peralta. Shock: concepts for a definition. Medicina (Argentina) 58: 341-349 (1999).
  • 7. JJ Poderoso, CL Lisdero, FJ Schopfer, NA Riobo, MC Carreras, E Cadenas, and A Boveris. The regulation of mitochondrial oxygen uptake by redox reactions involving nitric oxide and ubiquinol. J. Biol. Chem. 274: 37709-37716 (1999).
  • 8. EM Gatto, NA Riobo, MC Carreras, A Cherñavsky, A Rubio, L Satz, and JJ Poderoso. Overexpression of neutrophil neuronal nitric oxide synthase in Parkinson''s disease. Nitric oxide 4: 534-539 (2000).
  • 9. FJ Schopfer, NA Riobo, MC Carreras, B Alvarez, R Radi, A Boveris, E Cadenas, and JJ Poderoso. Oxidation of ubiquinol by peroxynitrite: implications for nitrosative damage in mitochondria. Biochem. J. 349: 35-42 (2000).
  • 10. MC Carreras, FJ Schopfer, CL Lisdero, NA Riobo, and Poderoso JJ. Mitochondrial function and nitric oxide utilization. Biol. Res. 33: 177-183 (2000).
  • 11. NA Riobo, E Clementi, M Melani, S Moncada, E Cadenas, A Boveris, and JJ Poderoso. Nitric oxide inhibits mitochondrial NADH-ubiquinone reductase activity through the formation of peroxynitrite. Biochem. J. 359: 139-145 (2001).
  • 12. NA Riobo, FJ Schopfer, A Boveris, E Cadenas, and JJ Poderoso. The reaction of nitric oxide and 6-hydroxydopamine: implications for Parkinson''s disease. Free Radic. Biol. & Med. 32(2): 115-121 (2002).
  • 13. EM Gatto, NA Riobo, MC Carreras, JJ Poderoso, and F Micheli. Neuroprotection in Parkinson''s disease: a commentary. Neurotoxicity Res. 4(2): 141-145 (2002).
  • 14. NA Riobo, M Melani, N Sanjuan, ML Fiszman, MC Gravrielle, MC Carreras, E Cadenas, and JJ Poderoso. The Modulation of mitochondrial nitric-oxide synthase activity in rat brain development. J. Biol. Chem. 277(45): 42447-42455 (2002).
  • 15. MC Carreras, M Melani, NA Riobo, DP Converso, EM Gatto, and JJ Poderoso. Neuronal nitric oxide synthases in brain and extraneural tissues. Meth. Enzymol. 359: 413-423 (2002).
  • 16. NA Riobo and DR Manning. Receptors coupled to heterotrimeric G proteins to the G12 family. Trends Pharmacol. Sci. 26(3):146-154 (2005).
  • 17. NA Riobo, GM Haines, and CP Emerson. Protein kinase C-delta and mitogen-activated protein/extracellular signal-regulated kinase-1 control Gli activation in Hedgehog signaling. Cancer Res. 66(2): 839-845 (2006).
  • 18. NA Riobo, X Ai, K Lu, GM Haines, and CP Emerson. PI3 kinase and Akt are essential for Sonic Hedgehog signaling. Proc. Natl. Acad. Sci. USA 103(12): 4505-4510 (2006).
  • 19. NA Riobo and CP Emerson. Hedgehog signal transduction: signal integration and cross talk in development and cancer. Cell Cycle 5(15): 1612-1615 (2006).
  • 20. NA Riobo, B Saucy, C DiLizio, and DR Manning. Activation of heterotrimeric G proteins by Smoothened. Proc. Natl. Acad. Sci. USA 103(33): 12607-12612 (2006).
  • 21. MV Gavrielides, A Gonzalez-Guerrico, NA Riobo, and MG Kazanietz. Androgens transcriptionally regulate PKCd expression in prostate cancer cells and modulate its apoptotic function. Cancer Res. 66(24): 11792-11801 (2006).
  • 22. NA Riobo and DR Manning. Pathways of signal transduction employed by vertebrate Hedgehogs. Biochem. J. 403: 369-379 (2007).
  • 23. MP Chinchilla and NA Riobo. Purification and bioassay of Hedgehog ligands for the study of cell death and survival. In "Programmed Cell Death" Meth. Enzymol. 446: 189-204 (2008)

Last Updated by Brian Borowski: Wednesday, April 28, 2010 2:39:04 PM

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