Basic Sciences
Division of Biomedical Engineering Sciences
School of Medicine
Loma Linda University
Loma Linda, CA 92350

Phone:  (909) 558-8371 Ext. 88371
Fax:  (909) 558-4083

Profile Photo

Research Interest

My current research interests center on the effects of ionizing radiation on normal cells and tissues.  It is normal tissues which set limits on radiation doses used in cancer therapy and it is normal tissues which set risk limits for occupational radiation exposures.  My laboratory investigates functional consequences of radiation exposure with emphasis on charged particle radiations such as protons, used at LLU for cancer therapy and accelerated ions of other elements (obtained at the Brookhaven National laboratory) that simulate cosmic rays encountered by astronauts.  We look at the brain, the immune system and bone as tissues that are at risk from radiation exposure and measure functions such as electrical signal formation/propagation or the ability to generate immune memory.  My interests in astronaut health also extend to effects of weightlessness and have involved experiments flown on five space shuttle missions.  I am also interested in how cells communicate information with each other and use radiation from microbeams to target individual cells in the model organism C. elegans.  These intestinal cells are able to generate signals that are received by unirradiated cells that in turn develop genotoxic damage.  Genetic screening techniques provide a means of identifying components of the signaling pathway and controlling the irradiation permits analysis of cell cooperation in transmitting/receiving the “bystander” signals

Selected Publications

  1. Sanchez MC, NELSON GA, Green LM. (2010)  Effects of protons and HZE particles on glutamate transport in astrocytes, neurons and mixed cultures. Radiat Res. 174(6):669-78. doi: 10.1667/RR2106.1. Epub 2010 Sep 28. PubMed PMID: 21128790.
  2. Titova E, Adami A, Ostrowski R, Lalas S, Vlkolinsky R, Zhang JH, Nelson G, Obenaus A. (2010) Radiation exposure prior to ischemia decreases lesion volume, brain edema and cell death. Acta Neurochir Suppl. 106:51-3. PMID: 19812920.
  3. Vlkolinsky R, Titova E, Krucker T, Chi BB, Staufenbiel M, NELSON GA, Obenaus  A. (2010) Exposure to 56Fe-particle radiation accelerates electrophysiological alterations in the hippocampus of APP23 transgenic mice. Radiat Res. 173(3):342-52. doi: 10.1667/RR1825.1. PubMed PMID: 20199219.
  4. Willey JS, Lloyd SA, NELSON GA, Bateman TA. (2011) Ionizing Radiation and Bone Loss:  Space Exploration and Clinical Therapy Applications. Clin Rev Bone Miner Metab. 9(1):54-62. PubMed PMID: 22826690.
  5. Willey JS, Lloyd SA, NELSON GA, Bateman TA. Space Radiation and Bone Loss. (2011)  Gravit Space Biol Bull. 25(1):14-21. PubMed PMID: 22826632.
  6. Lloyd SA, Bandstra ER, Willey JS, Riffle SE, Tirado-Lee L, NELSON GA, Pecaut MJ, Bateman TA. (2012)  Effect of proton irradiation followed by hindlimb unloading on bone in mature mice: a model of long-duration spaceflight. Bone. 51(4):756-64. doi: 10.1016/j.bone.2012.07.001.  PubMed PMID: 22789684.
  7. Latchney SE, Rivera PD, Mao XW, Ferguson VL, Bateman TA, Stodieck LS, NELSON GA, Eisch AJ. (2014) The effect of spaceflight on mouse olfactory bulb volume, neurogenesis, and cell death indicates the protective effect of novel environment. J Appl Physiol. (1985) 116(12):1593-604. Epub April 17. PubMed PMID: 24744382.
  8. Narici, L. and G. A. NELSON.  (2014)  CNS Risk.  J. Radiation Research 55 Suppl 1:  i18–i19.  doi: 10.1093/jrr/rrt207. 
  9. NELSON, G., Fike, J., Limoli, C.L., Obenaus, A., Raber, J., Soltesz, I. and Vlkolinsky, R. (2014)  Responses of the central nervous system to high linear energy transfer radiation: NSCOR project highlights. J. Radiat. Res. Mar 1;55 Suppl 1:i22-i23. doi: 10.1093/jrr/rrt214.
  10. NELSON, G., Jones, T., Ortloff, L., Ford, J., Nuñez, D. and L. Braby (2014)  Bystander signaling in C. elegans: proton microbeam studies.  J. Radiation Research 55 Suppl 1:  i118–i119  doi: 10.1093/jrr/rrt178.  (
  11. Raber J, Rudobeck E, Campbell-Beachler M, Allen AR, Allen B, Rosi S, NELSON GA, Ramachandran S, Turner J, Fike JR, Vlkolinsky R. (2014)  28Silicon radiation-induced enhancement of synaptic plasticity in the hippocampus of naïve  and cognitively tested mice. Radiat Res. 181(4):362-8. PMID: 24673255. 
  12. Rudobeck E, NELSON GA, Sokolova IV, Vlkolinský R.  (2014) 28silicon radiation impairs neuronal output in CA1 neurons of mouse ventral hippocampus without altering dendritic excitability. Radiat Res. 181(4):407-15. doi: 10.1667/RR13484.1. Epub 2014 Mar 13. PubMed PMID: 24625098. 
  13. Tseng, B., Giedzinski, E., Izadi, A., Suarez, T., Lan, M., Tran, K., Acharya. M.M., NELSON, G.A., Raber, J., Parihar, V and Limoli, C.L. (2014). Functional consequences of radiation-induced oxidative stress in cultured neural stem cells and the brain exposed to charged particle irradiation. Antioxid. Redox Signaling, 20(9):1410-22. Epub 2013 Aug 12.  PMID: 23802883
  14. Marty, V.N., R. Vlkolinsky, N. Minassian, T. Cohen, G. A. NELSON, and I. Spigelman (2014) Radiation-Induced Alterations in Synaptic Neurotransmission of Dentate Granule Cells Depend on the Dose and Species of Charged Particles. Radiation Research: 182(6): 653-665.
  15. NCRP Commentary No. 23 - Radiation Protection for Space Activities: Supplement to Previous Recommendations (2014).  Scientific Committee: Dudley Goodhead, Co-Chairman, R. Julian Preston, Co-Chairman, Patricia A. Fleming, Kathryn D. Held, Amy Kronenberg, Gregory A. NELSON, Walter Schimmerling, Roger P. Shaw and Michael M. Weil.  National Council on Radiation Protection and Measurements, Bethesda, MD.
  16. Parihar, V.K., Allen, B.D., Tran, K., Chmielewski, N.N., Craver, B.M., Martirosian, V., Morganti, J.M., Rosi, S., Vlkolinsky, R., Acharya, M.M., NELSON, G.A., Allen, A.R. and Limoli C.L. (2015)  Targeted overexpression of mitochondrial catalase prevents radiation-induced cognitive dysfunction. Antioxid. Redox Signaling, 22:78-91. Epub ahead of publ. Jul 29, 2014.  PMID: 24949841
  17. Sokolova I, Schneider CJ, Bezaire M, Soltesz I, Vlkolinsky R, NELSON GA: Proton Radiation Alters Intrinsic and Synaptic Properties of CA1 Pyramidal Neurons of the Mouse Hippocampus.  Radiat Res. 2015 Feb;183(2):208-18. doi: 10.1667/RR13785.1. Epub 2015 Jan 26. PubMed PMID: 25621896.
  18. Boerma M, NELSON GA, Sridharan V, Mao XW, Koturbash I, Hauer-Jensen M. Space radiation and cardiovascular disease risk. World J Cardiol. 2015 Dec 26;7(12):882-8. doi: 10.4330/wjc.v7.i12.882. Review. PubMed PMID: 26730293;PubMed Central PMCID: PMC4691814.
  19. Raber J, Allen AR, Sharma S, Allen B, Rosi S, Olsen RH, Davis MJ, Eiwaz M, Fike JR, NELSON GA. Effects of Proton and Combined Proton and (56)Fe Radiation on the Hippocampus. Radiat Res. 2015 Dec 31. [Epub ahead of print] PubMed PMID: 26720797.
  20. Nzabarushimana E, Prior S, Miousse IR, Pathak R, Allen AR, Latendresse J, Olsen RH, Raber J, Hauer-Jensen M, NELSON GA, Koturbash I. Combined exposure to protons and (56)Fe leads to overexpression of Il13 and reactivation of repetitive elements in the mouse lung. Life Sci Space Res (Amst). 2015 Nov;7:1-8. doi: 10.1016/j.lssr.2015.08.001. Epub 2015 Aug 18. PubMed PMID: 26553631; PubMedCentral PMCID: PMC4641818.