Departamento de Bioquímica
Alejandro Samhan Arias. Profesor Ayudante Doctor

Alejandro Samhan Arias

Profesor Ayudante Doctor

Departamento de Bioquímica

E-mail: alejandro.samhan@uam.es

Biosketch

I have a clear and logical mind with a practical approach to problem-solving and a drive to see things through to completion. I enjoy working on my own initiative or in a team. In short, I am reliable, I have a strong appetite for learning and a genuine interest to do research in general, but also focused in the understanding of the positive and deleterious effects of free radicals in life but more specifically related to human degenerative diseases.

My actual research nowadays includes the role of electron transfer systems in disease. Some other areas of interest also included in my next five years of research strategic plan are associated with the study of naturally occurring compounds as potential therapeutical agents against diseases. It is a priority in future researches to identify and have a better understanding of the mechanisms controlling the enzymes that generate reactive oxygen species, since they become key mediators in the development of pathophysiological conditions, cancer and aging.

My early and late publications directly addressed the study of the NADH dependent redox systems present at the neuronal plasma membrane and its role in neuronal cell death. Both cytochrome b5 reductase and cytochrome b5 have been shown as prominent components of the so-called “plasma membrane redox chain” as pro-apoptosis markers in cerebellar granule neurons. This early research was strongly devoted to this system with the aim to unveil the circumstances under which the electron shuttle uncouples, leading to a burst of reactive oxygen species, a precondition that is in general associated with neurodegeneration.

Research Activities - Keywords

  • Metalloenzymes, flavoproteins, structure-activity relationships
  • Reactive oxygen and nitrogen species (ROS/RNS) biochemistry - formation/elimination and enzymes structure-activity relationships
  • Mechanisms of ROS/RNS-mediated diseases
  • Cytochrome b5 reductase (rat, pig, and human), cytochrome b5, cytochrome c
  • Plasma membrane NAD(P)H oxidases
  • Reconstitution of electron transfer chains
  • Molecular modeling (protein-protein interactions, protein-ligand interactions)
  • Oxidative lipidomics

I have expertise in a multitude of biophysical and spectroscopic techniques (UV-vis, Raman, Fluorescence, CD and NMR).

Positions and Honours

  • 12/2019 up to date, Auxiliary Professor, (Competitive tender contract). Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), 28029 Madrid, Spain.
  • 12/2018 to 11/2019, Researcher (Investigador doutorado), (Competitive tender contract). LAQV. Chemistry Department.FCT. NOVA de Lisboa, Portugal. Funded by Fundação para a Ciência e a Tecnologia with FEDER co-funding.
  • 01/2018-09/2018, Post-doctoral fellow, (Renewal) LAQV. Chemistry Department.FCT. NOVA de Lisboa, Portugal.
  • 03/2015-12/2017, Post-doctoral fellow, (Competitive tender fellowship). UCIBIO. Chemistry Department.FCT. NOVA de Lisboa, Portugal. Funded by Fundação para a Ciência e a Tecnologia with FEDER co-funding.
  • 01/2015-02/2015, C.E.O of the Spanish Association of Crohn’s Diseases and Ulcerative Colitis Patients Associations.
  • 01/2011-12/2014, Research Associate, (Competitive tender contract). Dep. Biochemistry and Molecular Biology. Facultad de Ciencias. Funded by the Regional Government (Junta de Extremadura) with FEDER co-funding. Universidad de Extremadura, Badajoz, Spain.
  • 01/2008-06/2011, Postdoctoral Researcher, (Competitive tender fellowship). Environmental and Occupational Health Department. C. for Free Radical and Antioxidant Health. University of Pittsburgh, Pittsburgh, USA. Funded by the Regional Government (Junta de Extremadura) with FEDER co-funding.
  • 08/2006-10/2006, Short term scholar at the Institute of Aging, (Competitive tender fellowship). University of Florida Gainesville (USA). Funded by University of Extremadura.
  • 04/2007-06/2007, Short term scholar at the Institute of Aging, (Competitive tender fellowship). University of Florida Gainesville (USA). Funded by University of Extremadura.
  • 12/2004-11/2008, Pre-doctoral fellow, (Competitive tender fellowship). Dep. Biochemistry and Molecular Biology. Facultad de Ciencias. Universidad de Extremadura, Badajoz, Spain.
  • 04/2004-11/2004, Research technician. Dep. Biochemistry and Molecular Biology. Facultad de Ciencias. Universidad de Extremadura, Badajoz, Spain.
  • 11/2002-08/2003, Research technician. Dep. Biochemistry and Molecular Biology. Facultad de Ciencias. Universidad de Extremadura, Badajoz, Spain.

Publications

Full publications list can be found at ORCiD.

Selected References:

  • Human erythrocytes exposure to juglone leads to an increase of superoxide anion production associated with cytochrome b5 reductase uncoupling. Valério G.N., Gutiérrez-Merino C., Nogueira F.,Moura I, Moura, J.J.G. and Samhan-Arias A.K. BBA Bioenergetics 2020. DOI: 10.1016/j.bbabio.2019.148134.
  • Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c. Samhan-Arias AK, Fortalezas S, Cordas CM, Moura I, Moura JJG, Gutierrez-Merino C. Redox Biol. 2018 May;15:109-114. doi: 10.1016/j.redox.2017.11.021.
  • Purified NADH-cytochrome b5 reductase is a novel superoxide anion source inhibited by apocynin: sensitivity to nitric oxide and peroxynitrite. Samhan-Arias AK, Gutierrez-Merino C. Free Rad Biol Med (2014) 73:174-189 (DOI: 10.1016/j.freeradbiomed.2014.04.033).
  • Lipidomics identifies cardiolipin oxidation as a mitochondrial target for redox therapy of brain injury. Ji J, Kline AE, Amoscato A, Samhan-Arias AK, Sparvero LJ, Tyurin VA, Tyurina YY, Fink B, Manole MD, Puccio AM, Okonkwo DO, Cheng JP, Alexander H, Clark RS, Kochanek PM, Wipf P, Kagan VE, Bayır H. Nature Neuroscience (2012) 15:1407-1413 (DOI: 10.1038/nn.3195).
  • Oxidized phospholipids as biomarkers of tissue and cell damage with a focus on cardiolipin. Samhan-Arias AK, Ji J, Demidova OM, Sparvero LJ, Feng W, Tyurin V, Tyurina YY, Epperly MW, Shvedova AA, Greenberger JS, Bayır H, Kagan VE, Amoscato AA. Biochim Biophys Acta (2012) 1818:2413-2423 (DOI: 10.1016/j.bbamem.2012.03.014).
  • Stimulation and clustering of cytochrome b5 reductase in caveolin-rich lipid microdomains is an early event in oxidative stress-mediated apoptosis of cerebellar granule neurons. Samhan-Arias AK, Marques-da-Silva D, Yanamala N, Gutierrez-Merino C. J Proteomics (2012) 75:2934-2949 (DOI: 10.1016/j.jprot.2011.12.007).
  • A mitochondria-targeted inhibitor of cytochrome c peroxidase mitigates radiation-induced death. Atkinson J, Kapralov AA, Yanamala N, Tyurina YY, Amoscato AA, Pearce L, Peterson J, Huang Z, Jiang J, Samhan-Arias AK, Maeda A, Feng W, Wasserloos K, Belikova NA, Tyurin VA, Wang H, Fletcher J, Wang Y, Vlasova II, Klein-Seetharaman J, Stoyanovsky DA, Bayîr H, Pitt BR, Epperly MW, Greenberger JS, Kagan VE. Nat Commun (2011) 2:497 (DOI: 10.1038/ncomms1499).

Awards

  • Badajoz (Spain) Ph.D. Thesis Award for the best PhD thesis in the biomedical field at the University of Extremadura, 2008.

Member of Editorial Boards

Molecules, MDPI (years 2019- up to date) IMPACT FACTOR 2018: 3.060. RANKS 2018: "Physical and Theoretical Chemistry" Q2, "Pharmaceutical Science" 2018 Q1, "Organic Chemistry" Q2, "Medicine (miscellaneous)" Q2, "Drug Discovery" Q2, "Chemistry (miscellaneous)" Q1, "Analytical Chemistry" Q2