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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Structural Insights into the Dynamics of Water in SOD1 Catalysis and Drug Interactions

Superoxide dismutase 1 (SOD1) is a crucial enzyme that protects cells from oxidative damage by converting superoxide radicals into H 2 O 2 and O 2 . This detoxification process, essential for cellular homeostasis, relies on a precisely orchestrated catalytic mechanism involving the copper cation, while the zinc cation contributes to the structural integrity of the enzyme. This study presents the 2.3 Å crystal structure of human SOD1 (PDB ID: 9IYK), revealing an assembly of six homodimers and twelve distinct active sites. The water molecules form a complex hydrogen-bonding network that drives proton transfer and sustains active site dynamics. Our structure also uncovers subtle conformational changes that highlight the intrinsic flexibility of SOD1, which is essential for its function. Additionally, we observe how these dynamic structural features may be linked to pathological mutations associated with amyotrophic lateral sclerosis (ALS). By advancing our understanding of hSOD1’s mechanistic intricacies and the influence of water coordination, this study offers valuable insights for developing therapeutic strategies targeting ALS. Our structure’s unique conformations and active site interactions illuminate new facets of hSOD1 function, underscoring the critical role of structural dynamics in enzyme catalysis. Moreover, we conducted a molecular docking analysis using SOD1 for potential radical scavengers and Abelson non-receptor tyrosine kinase (c-Abl, Abl1) inhibitors targeting misfolded SOD1 aggregation along with oxidative stress and apoptosis, respectively. The results showed that CHEMBL1075867, a free radical scavenger derivative, showed the most promising docking results and interactions at the binding site of hSOD1, highlighting its promising role for further studies against SOD1-mediated ALS.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Bacterial Volatile Organic Compounds as a Strategy to Increase Drought Tolerance in Maize (Zea mays L.): Influence on Plant Biochemistry

Maize is highly susceptible to drought, which affects growth and yield. This study investigated how bacterial volatile organic compounds (BVOCs) affect maize drought tolerance. Drought reduced shoot size but increased root length, an adaptation for accessing deeper soil moisture. BVOCs from strain D12 significantly increased root length and shoot growth under drought conditions. Drought also altered root biochemistry, decreasing enzyme activity, and increased osmolyte levels. BVOCs from strains F11 and FS4-14 further increased osmolyte levels but did not protect membranes from oxidative damage, while BVOCs from strains D12 and D7 strains reduced osmolyte levels and cell damage. In shoots, drought increased the levels of osmolytes and oxidative stress markers. BVOCs from FS4-14 had minimal effects on shoot biochemistry. BVOCs from D12 and F11 partially restored metabolic activity but did not reduce cell damage. BVOCs from D7 reduced metabolic activity and cell damage. These results suggest that BVOCs can modulate the biochemical response of maize to drought, with some strains evidencing the potential to enhance drought tolerance.

Lopes, Tiago (ORCID:0000000330603315)↗
DOE OSTI2020

Late-life restoration of mitochondrial function reverses cardiac dysfunction in old mice

Diastolic dysfunction is a prominent feature of cardiac aging in both mice and humans. We show here that 8-week treatment of old mice with the mitochondrial targeted peptide SS-31 (elamipretide) can substantially reverse this deficit. SS-31 normalized the increase in proton leak and reduced mitochondrial ROS in cardiomyocytes from old mice, accompanied by reduced protein oxidation and a shift towards a more reduced protein thiol redox state in old hearts. Improved diastolic function was concordant with increased phosphorylation of cMyBP-C Ser282 but was independent of titin isoform shift. Late-life viral expression of mitochondrial-targeted catalase (mCAT) produced similar functional benefits in old mice and SS-31 did not improve cardiac function of old mCAT mice, implicating normalizing mitochondrial oxidative stress as an overlapping mechanism. These results demonstrate that pre-existing cardiac aging phenotypes can be reversed by targeting mitochondrial dysfunction and implicate mitochondrial energetics and redox signaling as therapeutic targets for cardiac aging.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1985

Thermal barrier coating life prediction model development

The objective is to develop an integrated life prediction model accounting for all potential life-limiting thermal barrier coating (TBC) degradation and failure modes, including spallation resulting from cyclic thermal stress, oxidation degradation, hot corrosion, erosion and foreign object damage.

Demasi, J. T.↗
NASA NTRS1991

Caenorhabditis elegans - A model system for space biology studies

The utility of the nematode Caenorhabditis elegans in studies spanning aspects of development, aging, and radiobiology is reviewed. These topics are interrelated via cellular and DNA repair processes especially in the context of oxidative stress and free-radical metabolism. The relevance of these research topics to problems in space biology is discussed and properties of the space environment are outlined. Exposure to the space-flight environment can induce rapid changes in living systems that are similar to changes occurring during aging; manipulation of these environmental parameters may represent an experimental strategy for studies of development and senescence. The current and future opportunities for such space-flight experimentation are presented.

Johnson, Thomas E.↗
NASA NTRS2001

The Effects of Long-Term Feeding of Rodent Food Bars on Lipid Peroxidation And Antioxidant Enzyme Levels In Fisher Rats

A specialized rodent food bar diet has been developed and utilized successfully for short-duration shuttle missions. Recent tests conducted in preparation for experiments aboard the International Space Station (ISS) indicated that long-term food bar feeding for three months induced hyperlipidemia in rats. This study examined oxidative stress status in livers of these same animals. Spectrophotometric analysis of 79 Fischer rat livers (40 female and 39 male) for lipid peroxidation (LPO) and superoxide dismutase (SOD) was conducted using Bioxytech LPO-587(TM) assay kit and SOD-525(Tm) assay kit, respectively. The treatment groups consisted of 20 male CHOW and 19 male FOOD BAR rats and 20 female CHOW and 20 female FOOD BAR rats. Statistical analysis to compare differences between groups was performed by standard analysis of variance procedures. The male FOOD BAR group LPO mean (3.6 +/- 0.2 mmol/g) was significantly (p less than or equal to 0.05) greater than that of the male CHOW group (2.1 +/-0.1 mmol/g). Moreover the female FOOD BAR group LPO mean (2.9 +/-0.1 mmol/g) was also significantly greater than the female CHOW group mean (2.2 +/-0.1 mmol/g). The mean values for SOD in both male and female groups showed no significant differences between CHOW and FOOD BAR groups. These results show that LPO levels were significantly higher in both the male and female FOOD BAR groups compared to CHOW groups and that there was no concomitant increase in SOD levels across the group. In addition, males showed a greater difference than females in terms of LPO levels. These findings suggest a need for further investigation into the use of the current food bar formulation for long-term experiments such as those planned for the ISS.

Ramirez, Joel↗
NASA NTRS2003

Subcellular targeting of nine calcium-dependent protein kinase isoforms from Arabidopsis

Calcium-dependent protein kinases (CDPKs) are specific to plants and some protists. Their activation by calcium makes them important switches for the transduction of intracellular calcium signals. Here, we identify the subcellular targeting potentials for nine CDPK isoforms from Arabidopsis, as determined by expression of green fluorescent protein (GFP) fusions in transgenic plants. Subcellular locations were determined by fluorescence microscopy in cells near the root tip. Isoforms AtCPK3-GFP and AtCPK4-GFP showed a nuclear and cytosolic distribution similar to that of free GFP. Membrane fractionation experiments confirmed that these isoforms were primarily soluble. A membrane association was observed for AtCPKs 1, 7, 8, 9, 16, 21, and 28, based on imaging and membrane fractionation experiments. This correlates with the presence of potential N-terminal acylation sites, consistent with acylation as an important factor in membrane association. All but one of the membrane-associated isoforms targeted exclusively to the plasma membrane. The exception was AtCPK1-GFP, which targeted to peroxisomes, as determined by covisualization with a peroxisome marker. Peroxisome targeting of AtCPK1-GFP was disrupted by a deletion of two potential N-terminal acylation sites. The observation of a peroxisome-located CDPK suggests a mechanism for calcium regulation of peroxisomal functions involved in oxidative stress and lipid metabolism.

Non-NASA Center↗
NASA NTRS2004

Melt-infiltrated Sic Composites for Gas Turbine Engine Applications

SiC-SiC ceramic matrix composites (CMCs) manufactured by the slurry -cast melt-infiltration (MI) process are leading candidates for many hot-section turbine engine components. A collaborative program between Goodrich Corporation and NASA-Glenn Research Center is aimed at determining and optimizing woven SiC/SiC CMC performance and reliability. A variety of composites with different fiber types, interphases and matrix compositions have been fabricated and evaluated. Particular focus of this program is on the development of interphase systems that will result in improved intermediate temperature stressed-oxidation properties of this composite system. The effect of the different composite variations on composite properties is discussed and, where appropriate, comparisons made to properties that have been generated under NASA's Ultra Efficient Engine Technology (UEET) Program.

Morscher, Gregory N.↗
NASA NTRS1998

BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz magnetic fields

We screened a panel of 1,920 randomly selected cDNAs to discover genes that are differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT) or X rays (5 Gy) compared to unexposed cells. Identification of these clones was accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen cDNAs differentially expressed in X-irradiated compared to control HL60 cells were recovered from a panel of 1,920 clones. Differential expression in experimental compared to control cells was confirmed independently by Northern blotting of paired total RNA samples hybridized to each of the 18 clone-specific cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced matches with the database for genes related to cell growth, protein synthesis, energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin, copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920 cDNAs revealed no differences greater than 1.5-fold in expression levels in magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and control samples were analyzed further for the presence of mRNA encoding X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA from exposed and control HL60 cells. Our results suggest that differential gene expression is induced in approximately 1% of a random pool of cDNAs by ionizing radiation but not by 60 Hz magnetic fields under the present experimental conditions.

Non-NASA Center↗
NASA NTRS1997

Latent transforming growth factor beta1 activation in situ: quantitative and functional evidence after low-dose gamma-irradiation

The biological activity of transforming growth factor beta1 (TGF-beta) is controlled by its secretion as a latent complex in which it is noncovalently associated with latency-associated peptide (LAP). Activation is the extracellular process in which TGF-beta is released from LAP, and is considered to be a primary regulatory control. We recently reported rapid and persistent changes in TGF-beta immunoreactivity in conjunction with extracellular matrix remodeling in gamma-irradiated mouse mammary gland. Our hypothesis is that these specific changes in immunoreactivity are indicative of latent TGF-beta activation. In the present study, we determined the radiation dose response and tested whether a functional relationship exists between radiation-induced TGF-beta and collagen type III remodeling. After radiation exposures as low as 0.1 Gy, we detected increased TGF-beta immunoreactivity in the mammary epithelium concomitant with decreased LAP immunostaining, which are events consistent with activation. Quantitative image analysis demonstrated a significant (P=0.0005) response at 0.1 Gy without an apparent threshold and a linear dose response to 5 Gy. However, in the adipose stroma, loss of LAP demonstrated a qualitative threshold at 0.5 Gy. Loss of LAP paralleled induction of collagen III immunoreactivity in this tissue compartment. We tested whether TGF-beta mediates collagen III expression by treating animals with TGF-beta panspecific monoclonal antibody, 1D11.16, administered i.p. shortly before irradiation. Radiation-induced collagen III staining in the adipose stroma was blocked in an antibody dose-dependent manner, which persisted through 7 days postirradiation. RNase protection assay revealed that radiation-induced elevation of total gland collagen III mRNA was also blocked by neutralizing antibody treatment. These data provide functional confirmation of the hypothesis that radiation exposure leads to latent TGF-beta activation, support our interpretation of the reciprocal shift in immunoreactivity as evidence of activation, and implicate TGF-beta as a mediator of tissue response to ionizing radiation. The sensitivity of activation to low radiation doses points to a potential role for TGF-beta in orchestrating tissue response to oxidative stress. As such, radiation may be useful as a probe to delineate the consequences of latent TGF-beta activation in situ.

NASA Discipline Radiation Health↗
NASA NTRS2008

Electrical Resistance as a NDE Technique to Monitor Processing and Damage Accumulation in SiC/SiC Composites

Ceramic matrix composites are suitable for high temperature structural applications such as turbine airfoils and hypersonic thermal protection systems. The employment of these materials in such applications is limited by the ability to process components reliable and to accurately monitor and predict damage evolution that leads to failure under stressed-oxidation conditions. Current nondestructive methods such as ultrasound, x-ray, and thermal imaging are limited in their ability to quantify small scale, transverse, in-plane, matrix cracks developed over long-time creep and fatigue conditions. Electrical resistance of SiC/SiC composites is one technique that shows special promise towards this end. Since both the matrix and the fibers are conductive, changes in matrix or fiber properties should relate to changes in electrical conductivity along the length of a specimen or part. Initial efforts to quantify the electrical resistance of different fiber and different matrix SiC/SiC composites will be presented. Also, the effect of matrix cracking on electrical resistivity for several composite systems will be presented. The implications towards electrical resistance as a technique applied to composite processing, damage detection, and life-modeling will be discussed.

Smith, Craig↗
NASA NTRS2009

Development of a GCR Event-based Risk Model

A goal at NASA is to develop event-based systems biology models of space radiation risks that will replace the current dose-based empirical models. Complex and varied biochemical signaling processes transmit the initial DNA and oxidative damage from space radiation into cellular and tissue responses. Mis-repaired damage or aberrant signals can lead to genomic instability, persistent oxidative stress or inflammation, which are causative of cancer and CNS risks. Protective signaling through adaptive responses or cell repopulation is also possible. We are developing a computational simulation approach to galactic cosmic ray (GCR) effects that is based on biological events rather than average quantities such as dose, fluence, or dose equivalent. The goal of the GCR Event-based Risk Model (GERMcode) is to provide a simulation tool to describe and integrate physical and biological events into stochastic models of space radiation risks. We used the quantum multiple scattering model of heavy ion fragmentation (QMSFRG) and well known energy loss processes to develop a stochastic Monte-Carlo based model of GCR transport in spacecraft shielding and tissue. We validated the accuracy of the model by comparing to physical data from the NASA Space Radiation Laboratory (NSRL). Our simulation approach allows us to time-tag each GCR proton or heavy ion interaction in tissue including correlated secondary ions often of high multiplicity. Conventional space radiation risk assessment employs average quantities, and assumes linearity and additivity of responses over the complete range of GCR charge and energies. To investigate possible deviations from these assumptions, we studied several biological response pathway models of varying induction and relaxation times including the ATM, TGF -Smad, and WNT signaling pathways. We then considered small volumes of interacting cells and the time-dependent biophysical events that the GCR would produce within these tissue volumes to estimate how GCR event rates mapped to biological signaling induction and relaxation times. We considered several hypotheses related to signaling and cancer risk, and then performed simulations for conditions where aberrant or adaptive signaling would occur on long-duration space mission. Our results do not support the conventional assumptions of dose, linearity and additivity. A discussion on how event-based systems biology models, which focus on biological signaling as the mechanism to propagate damage or adaptation, can be further developed for cancer and CNS space radiation risk projections is given.

Cucinotta, Francis A.↗
NASA NTRS2010

Novel Thermotolerant Siderophilic Filamentous Cyanobacterium that Produces Intracellular Iron-Rich Phases

Cyanobacteria are the main producers of organic compounds in iron-depositing hot springs despite photosynthetically generated-oxygen and the abundance of reduced iron (Fe2+) that likely leads to enormous oxidative stress within cyanobacterial cells. Therefore, the study of cyanobacterial diversity, phylogeny, and biogeochemical activity in iron-depositing hot springs will not only provide insights into the contribution of CB to iron redox cycling in these environments, but it could also provide insights into CB evolution. This study characterizes the phylogeny, morphology, and physiology of isolate JSC-1, a novel filamentous CB isolated from an iron-depositing hot spring. While isolate JSC-1 is morphologically similar to the CB genus Leptolyngbya, 16S rDNA sequence data indicated that it shares 95 percent sequence similarity to the type strain L. boryanum. Strain JSC-1 fixes N2 and exhibited an unusually high ratio between photosystem (PS) I and PS II and was capable of complementary chromatic adaptation. Further, it synthesized only chlorophyll a and a unique set of carotenoids. Strain JSC-1 not only required high levels of Fe for growth (greater than or equal to 40 microM), but it also accumulated large amounts of extracellular ferrihydrite and generated intracellular ferric phosphates. Strain JSC-1 was found to secrete 2-oxoglutaric acid and possesses one ortholog and one paralog of bacterioferritin. Surprisingly, the latter has 70.13 % identity with a bacterioferritin in marine-proteobacterium HTCC 2080 and has joint node with bacterioferritins found in enterobacteria. Collectively, these observations provide insights into the physiological strategies that might have allowed CB to develop and proliferate in Fe-rich environments. Based on its genotypic and phenotypic characterization of strain, JSC-1 represents a new operational taxonomical unit (OTU) JSC-1.

Broun, Igor I.↗
NASA NTRS2010

A Comparison of Molecular and Histopathological Changes in Mouse Intestinal Tissue Following Whole-Body Proton- or Gamma-Irradiation

There are many consequences following exposure to the space radiation environment which can adversely affect the health of a crew member. Acute radiation syndrome (ARS) involving nausea and vomiting, damage to radio-sensitive tissue such as the blood forming organs and gastrointestinal tract, and cancer are some of these negative effects. The space radiation environment is ample with protons and contains gamma rays as well. Little knowledge exists to this point, however, regarding the effects of protons on mammalian systems; conversely several studies have been performed observing the effects of gamma rays on different animal models. For the research presented here, we wish to compare our previous work looking at whole-body exposure to protons using a mouse model to our studies of mice experiencing whole-body exposure to gamma rays as part of the radio-adaptive response. Radio-adaptation is a well-documented phenomenon in which cells exposed to a priming low dose of radiation prior to a higher dose display a reduction in endpoints like chromosomal aberrations, cell death, micronucleus formation, and more when compared to their counterparts receiving high dose-irradiation only. Our group has recently completed a radio-adaptive experiment with C57BL/6 mice. For both this study and the preceding proton research, the gastrointestinal tract of each animal was dissected four hours post-irradiation and the isolated small intestinal tissue was fixed in formalin for histopathological examination or snap-frozen in liquid nitrogen for RNA isolation. Histopathologic observation of the tissue using standard H&E staining methods to screen for morphologic changes showed an increase in apoptotic lesions for even the lowest doses of 0.1 Gy of protons and 0.05 Gy of gamma rays, and the percentage of apoptotic cells increased with increasing dose. A smaller percentage of crypts showed 3 or more apoptotic lesions in animals that received 6 Gy of gamma-irradiation compared to mice receiving only 2 Gy of protons. Tissue of the gastrointestinal tract was also homogenized and RNA was isolated for cDNA synthesis and real-time PCR analysis. Inspecting apoptotic lesions of the duodenum of the small intestine as an endpoint of damage did not reveal a radio-adaptive response in C57BL/6 mice at the four hour time point. Results of gene expression changes showed consistent up or down regulation of a number of genes for all of the exposure doses that may play a role in proton-induced apoptosis. Preliminary results of gene expression alterations as a result of gamma-irradiation revealed a wealth of genes involved in oxidative stress and antioxidant defense processes being up- or down-regulated only at the highest exposure dose of 6 Gy and the combined dose of 5 cGy with 6 Gy. Those animals undergoing only 5 cGy of gamma-irradiation showed very little modification of gene expression. Taken together these results lead us to conclude that protons cause more severe morphologic damage to the duodenum of the small intestine at a dose of 2 Gy than a higher dose of 6 Gy of gamma rays to the same organ. Both protons and gamma rays lead to significant variation in gene expression at high doses in the small intestine and these changes may provide insight into the mechanism of injury seen in the gastrointestinal tract following radiation exposure. Astronauts experiencing prolonged exposure to protons in the low Earth orbit and in deep space, and experiencing acute exposure to protons from solar particle events, may face biological consequences that will impact a mission s success. We will continue this work by studying, quantifying, and comparing damage due to protons and gamma rays in the small intestine as well as other organs in a time-dependent manner.

Purgason, Ashley↗
NASA NTRS2010

DF-1, A Nontoxic Carbon Fullerene Based Antioxidant, is Effective as a Biomedical Countermeasure Against Radiation

A long-term goal of radiation research is the mitigation of inherent risks of radiation exposure. Thus the study and development of safe agents, whether biomedical or dietary, that act as effective radioprotectors is an important step in accomplishing this long-term goal. Some of the most effective agents to date have been aminothiols and their derivatives. Unfortunately, most of these agents have side effects such as nausea, vomiting, hypotension, weakness, and fatigability. For example, nausea and emesis occur in most patients treated with WR-2721 (Amifostine), requiring the use of effective antiemetics, with hypotension being the dose-limiting side effect in patients treated. Clearly, the need for a radioprotector that is both effective and safe still exists. Development of biocompatible nano-materials for radioprotection is a promising emerging technology that could be exploited to address the need to minimize biological effects when exposure is unavoidable. Testing free radical scavenging nanoparticles for potential use in radioprotection is exciting and highly relevant. Initial investigations presented here demonstrate the ability of a particular functionalized carbon fullerene nanoparticle, (DF-1), to act as an effective radioprotector. DF-1 was first identified as the most promising candidate in a screen of several functionalized carbon fullerenes based on lack of toxicity and antioxidant therapeutic potential against oxidative injuries (i.e. organ reperfusion and ionizing radiation). Subsequently, DF-1 has been shown to reduce chromosome aberration yield and cell death, as well as overall ROS levels in human lymphocytes and fibroblasts after exposure to gamma radiation and energetic protons while demonstrating no associated toxicity. The dose-reducing factor of DF-1 at LD50 is nearly 2.0 for gamma radiation. In addition, DF-1 treatment also significantly prevented cell cycle arrest after exposure. Finally, DF-1 markedly attenuated COX2 upregulation in cell culture after irradiation thus preventing an inflammatory response to irradiation. Taken together, these results suggest that DF-1 provides potent protection against several deleterious cellular consequences of irradiation in mammalian systems including oxidative stress, DNA damage, inflammation and cell death.

Theriot, Corey A.↗
NASA NTRS2011

Low Fluid Shear Culture of Staphylococcus Aureus Represses hfq Expression and Induces an Attachment-Independent Biofilm Phenotype

Background: The opportunistic pathogen, Staphylococcus aureus, experiences fluctuations in fluid shear during infection and colonization of a human host. Colonization frequently occurs at mucus membrane sites such as in the gastrointestinal tract where the bacterium may experience low levels of fluid shear. The response of S. aureus to low fluid shear remains unclear. Methods: S. aureus was cultured to stationary phase using Rotating-Wall Vessel (RWV) bioreactors which produce a physiologically relevant low fluid shear environment. The bacterial aggregates that developed in the RWV were evaluated by electron microscopy as well as for antibiotic resistance and other virulence-associated stressors. Genetic expression profiles for the low-shear cultured S. aureus were determined by microarray analysis and quantitative real-time PCR. Results: Planktonic S. aureus cultures in the low-shear environment formed aggregates completely encased in high amounts of extracellular polymeric substances. In addition, these aggregates demonstrated increased antibiotic resistance indicating attachment-independent biofilm formation. Carotenoid production in the low-shear cultured S. aureus was significantly decreased, and these cultures displayed an increased susceptibility to oxidative stress and killing by whole blood. The hfq gene, associated with low-shear growth in Gram negative organisms, was also found to be down-regulated in S. aureus. Conclusions: Collectively, this data suggests that S. aureus decreases virulence characteristics in favor of a biofilm-dwelling colonization phenotype in response to a low fluid shear environment. Furthermore, the identification of an Hfq response to low-shear culture in S. aureus, in addition to the previously reported responses in Gram negative organisms, strongly suggests an evolutionarily conserved response to mechanical stimuli among structurally diverse prokaryotes.

Ott, C. Mark↗
NASA NTRS2011

Evaluation of the Combined Effects of Gamma Radiation and High Dietary Iron on Peripheral Leukocyte Distribution and Function

NASA is concerned with the health risks to astronauts, particularly those risks related to radiation exposure. Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of (A) peripheral leukocyte distribution; (B) plasma cytokine levels; (C) cytokine production profiles following whole blood stimulation of either T cells or monocytes.

Crucian, Brian E.↗
NASA NTRS2011

Radiation Protection Using Single-Wall Carbon Nanotube Derivatives

This invention is a means of radiation protection, or cellular oxidative stress mitigation, via a sequence of quenching radical species using nano-engineered scaffolds, specifically single-wall carbon nanotubes (SWNTs) and their derivatives. The material can be used as a means of radiation protection by reducing the number of free radicals within, or nearby, organelles, cells, tissue, organs, or living organisms, thereby reducing the risk of damage to DNA and other cellular components (i.e., RNA, mitochondria, membranes, etc.) that can lead to chronic and/or acute pathologies, including but not limited to cancer, cardiovascular disease, immuno-suppression, and disorders of the central nervous system. In addition, this innovation could be used as a prophylactic or antidote for accidental radiation exposure, during high-altitude or space travel where exposure to radiation is anticipated, or to protect from exposure from deliberate terrorist or wartime use of radiation- containing weapons.

Tour, James M.↗