free radicals

Summary

Summary: Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.

Top Publications

  1. Sumida Y, Niki E, Naito Y, Yoshikawa T. Involvement of free radicals and oxidative stress in NAFLD/NASH. Free Radic Res. 2013;47:869-80 pubmed publisher
    ..This review article is focused on the role of free radicals and free radical-mediated lipid peroxidation in the pathogenesis of NAFLD and NASH, taking characteristic ..
  2. McCusker K, Medzihradszky K, Shiver A, Nichols R, Yan F, Maltby D, et al. Covalent intermediate in the catalytic mechanism of the radical S-adenosyl-L-methionine methyl synthase RlmN trapped by mutagenesis. J Am Chem Soc. 2012;134:18074-81 pubmed publisher
    ..Together, these experiments provide compelling evidence for the formation of a covalent intermediate species between RlmN and its rRNA substrate and well as the roles of the conserved cysteine residues in catalysis...
  3. Mal P, Dutta K, Bandyopadhyay D, Basu A, Khan R, Bishayi B. Azithromycin in combination with riboflavin decreases the severity of Staphylococcus aureus infection induced septic arthritis by modulating the production of free radicals and endogenous cytokines. Inflamm Res. 2013;62:259-73 pubmed publisher
    ..To determine alternate therapeutic measures to combat Staphylococcus aureus induced arthritis. Thus, azithromycin was combined with riboflavin, which may combat the ROS production and inflammation...
  4. Griffiths H, Dunston C, Bennett S, Grant M, Phillips D, Kitas G. Free radicals and redox signalling in T-cells during chronic inflammation and ageing. Biochem Soc Trans. 2011;39:1273-8 pubmed publisher
    ..Together, these data suggest that a complex relationship exists between intra- and extra-cellular redox compartments which contribute to the T-cell phenotype...
  5. Bocci V, Valacchi G. Free radicals and antioxidants: how to reestablish redox homeostasis in chronic diseases?. Curr Med Chem. 2013;20:3397-415 pubmed
    ..It is hoped to evaluate this integrated medical approach because it represents a sheet anchor for many patients. ..
  6. Maeda H. The link between infection and cancer: tumor vasculature, free radicals, and drug delivery to tumors via the EPR effect. Cancer Sci. 2013;104:779-89 pubmed publisher
    ..This review describes the barriers and countermeasures for improved drug delivery to tumors by using nanomedicines...
  7. Vassallo D, Simoes M, Furieri L, Fioresi M, Fiorim J, Almeida E, et al. Toxic effects of mercury, lead and gadolinium on vascular reactivity. Braz J Med Biol Res. 2011;44:939-46 pubmed
    ..via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function...
  8. O Connell K, Littleton Kearney M. The role of free radicals in traumatic brain injury. Biol Res Nurs. 2013;15:253-63 pubmed publisher
    ..b>Free radicals are implicated as major contributors to the secondary injury...
  9. Saravia J, Lee G, Lomnicki S, Dellinger B, Cormier S. Particulate matter containing environmentally persistent free radicals and adverse infant respiratory health effects: a review. J Biochem Mol Toxicol. 2013;27:56-68 pubmed publisher
    ..of PM-mediated respiratory damage, with a focus on the emerging importance of environmentally persistent free radicals (EPFRs) ubiquitously present in combustion-derived PM...

More Information

Publications62

  1. Agarwal A, Allamaneni S. Free radicals and male reproduction. J Indian Med Assoc. 2011;109:184-7 pubmed
    ..Extensive research in the last decade has led to the identification of free radicals (reactive oxygen species) as mediators of sperm dysfunction in both specific diagnoses and idiopathic cases of ..
  2. Takashima M, Horie M, Shichiri M, Hagihara Y, Yoshida Y, Niki E. Assessment of antioxidant capacity for scavenging free radicals in vitro: a rational basis and practical application. Free Radic Biol Med. 2012;52:1242-52 pubmed publisher
    With increasing evidence showing the involvement of oxidative stress induced by free radicals in the development of various diseases, the role of radical-scavenging antioxidants has received much attention...
  3. Morinaga H, Sugiyama H, Inoue T, Takiue K, Kikumoto Y, Kitagawa M, et al. Effluent free radicals are associated with residual renal function and predict technique failure in peritoneal dialysis patients. Perit Dial Int. 2012;32:453-61 pubmed publisher
    ..Residual renal function (RRF) is associated with low oxidative stress in peritoneal dialysis (PD). In the present study, we investigated the relationship between the impact of oxidative stress on RRF and patient outcomes during PD...
  4. Marsh E, Meléndez G. Adenosylcobalamin enzymes: theory and experiment begin to converge. Biochim Biophys Acta. 2012;1824:1154-64 pubmed publisher
    ..The role of the cofactor as the initiator of reactive free radicals needed for these reactions is well established...
  5. Morita M, Ishida N, Uchiyama K, Yamaguchi K, Itoh Y, Shichiri M, et al. Fatty liver induced by free radicals and lipid peroxidation. Free Radic Res. 2012;46:758-65 pubmed publisher
    ..These results show that free radicals as well as high fat diet induce fatty liver by similar mechanisms, in which lipid peroxidation may be involved.
  6. Simões C, Domingues P, Domingues M. Identification of free radicals in oxidized and glycoxidized phosphatidylethanolamines by spin trapping combined with tandem mass spectrometry. Rapid Commun Mass Spectrom. 2012;26:931-9 pubmed publisher
    ..Glycated PEs are more easily oxidized, enhancing oxidative stress. This study aims to evaluate the influence of glycation on the formation of intermediate radical species during oxidation of glycated PEs...
  7. Pawłowska Góral K, Pilawa B. Detection of free radicals formed by in vitro metabolism of fluoride using EPR spectroscopy. Toxicol In Vitro. 2011;25:1269-73 pubmed publisher
    ..The findings, however, are incomplete and divergent. The aim of our study was to determine the presence of free radicals in hepatocytes exposed to fluoride in concentrations which do not lead to changes in the concentrations of ..
  8. Piechota Polanczyk A, Goraca A, Demyanets S, Mittlboeck M, Domenig C, Neumayer C, et al. Simvastatin decreases free radicals formation in the human abdominal aortic aneurysm wall via NF-?B. Eur J Vasc Endovasc Surg. 2012;44:133-7 pubmed publisher
    Statins have been reported to suppress the progression of abdominal aortic aneurysm (AAA). However, the effects of statins on inflammatory processes and free radicals generation are poorly understood.
  9. Hioe J, Zipse H. Hydrogen transfer in SAM-mediated enzymatic radical reactions. Chemistry. 2012;18:16463-72 pubmed publisher
    ..The use of SAM in spore photoproduct lyase (SPL) appears to fit neither of these general categories and appears to constitute the first example of a SAM-initiated radical reaction propagated independently of the cofactor...
  10. Shisler K, Broderick J. Emerging themes in radical SAM chemistry. Curr Opin Struct Biol. 2012;22:701-10 pubmed publisher
    ..Recently characterized superfamily members are providing new examples of the remarkable range of reactions that can be catalyzed, as well as new structural and mechanistic insights into these fascinating reactions...
  11. Sarkar D, Kundu S, De S, Hariharan C, Saha P, Manna A, et al. The antioxidant activity of allylpyrocatechol is mediated via decreased generation of free radicals along with escalation of antioxidant mechanisms. Phytother Res. 2013;27:324-9 pubmed publisher
    ..Taken together, APC exhibited an antioxidant activity which was mediated both via decreased generation of free radicals along with increase in cellular antioxidants.
  12. Tian L, Wang H, Abdallah A, Prinyawiwatkul W, Xu Z. Red and white wines inhibit cholesterol oxidation induced by free radicals. J Agric Food Chem. 2011;59:6453-8 pubmed publisher
    ..Catechin may play a more important role than resveratrol in inhibiting cholesterol oxidation...
  13. Wilczyński S, Pilawa B, Koprowski R, Wróbel Z, Ptaszkiewicz M, Swakoń J, et al. EPR studies of free radicals decay and survival in gamma irradiated aminoglycoside antibiotics: sisomicin, tobramycin and paromomycin. Eur J Pharm Sci. 2012;45:251-62 pubmed publisher
    ..But on the other hand radiosterilization can lead to radiolytic products appearing, in example free radicals. Free radicals in radiative sterilized sisomicin, tobramycin and paromomycin were studied by electron ..
  14. Zhang Q, van der Donk W, Liu W. Radical-mediated enzymatic methylation: a tale of two SAMS. Acc Chem Res. 2012;45:555-64 pubmed publisher
    ..The diverse strategies for using two SAM molecules reflect the rich chemistry of radical-mediated methylation reactions and the remarkable versatility of the radical SAM superfamily...
  15. Ahn H, Kim K, Kim G, Moon E, Yang S, Lee J. Atmospheric-pressure plasma jet induces apoptosis involving mitochondria via generation of free radicals. PLoS ONE. 2011;6:e28154 pubmed publisher
    ..Taken together, our data suggest the potential employment of plasma jets as a novel therapy for cancer...
  16. Rosenblat M, Elias A, Volkova N, Aviram M. Monocyte-macrophage membrane possesses free radicals scavenging activity: stimulation by polyphenols or by paraoxonase 1 (PON1). Free Radic Res. 2013;47:257-67 pubmed publisher
    In the current study, we analysed free radicals scavenging activity of monocytes-macrophages in the absence or presence of antioxidants such as polyphenols or paraoxonase 1 (PON1). THP-1 human monocytic cell line, murine J774A...
  17. Da Costa L, Garcia Bailo B, BADAWI A, El Sohemy A. Genetic determinants of dietary antioxidant status. Prog Mol Biol Transl Sci. 2012;108:179-200 pubmed publisher
    ..Endogenous production of free radicals occurs during normal physiological processes, such as aerobic metabolism, oxidation of biological molecules, ..
  18. Faião Flores F, Coelho P, Muniz R, Souza G, Arruda Neto J, Maria D. Antitumor potential induction and free radicals production in melanoma cells by Boron Neutron Capture Therapy. Appl Radiat Isot. 2011;69:1748-51 pubmed publisher
    ..The cellular viability and the oxidative stress were determined. BNCT induced free radicals production and proliferative potential inhibition in melanoma cells...
  19. Hosseinimehr S, Mahmoudzadeh A, Ahmadi A, Ashrafi S, Shafaghati N, Hedayati N. The radioprotective effect of Zataria multiflora against genotoxicity induced by ? irradiation in human blood lymphocytes. Cancer Biother Radiopharm. 2011;26:325-9 pubmed publisher
    ..extract exhibited concentration-dependent radical-scavenging activity on 1,1-diphenyl-2-picryl hydrazyl free radicals. These data have an important application for the protection of human lymphocyte from the genetic damage and ..
  20. Barrera L, Cassidy A, Wang W, Wei T, Belshaw N, Johnson I, et al. TrxR1 and GPx2 are potently induced by isothiocyanates and selenium, and mutually cooperate to protect Caco-2 cells against free radical-mediated cell death. Biochim Biophys Acta. 2012;1823:1914-24 pubmed publisher
  21. Jaganjac M, Tirosh O, Cohen G, Sasson S, Zarkovic N. Reactive aldehydes--second messengers of free radicals in diabetes mellitus. Free Radic Res. 2013;47 Suppl 1:39-48 pubmed publisher
    ..Reactive aldehydes, especially 4-hydroxynonenal (HNE), are considered as second messengers of free radicals that act both as signaling molecules and as cytotoxic products of lipid peroxidation causing long-lasting ..
  22. Spasojevic I. Free radicals and antioxidants at a glance using EPR spectroscopy. Crit Rev Clin Lab Sci. 2011;48:114-42 pubmed publisher
    The delicate balance between the advantageous and detrimental effects of free radicals is one of the important aspects of human (patho)physiology...
  23. Tomter A, Zoppellaro G, Schmitzberger F, Andersen N, Barra A, Engman H, et al. HF-EPR, Raman, UV/VIS light spectroscopic, and DFT studies of the ribonucleotide reductase R2 tyrosyl radical from Epstein-Barr virus. PLoS ONE. 2011;6:e25022 pubmed publisher
    ..Comparison with previous studies of RNR R2s from mouse, bacteria, and herpes viruses, demonstrates that finely tuned electronic properties of the radical exist within the same RNR R2 Ia class...
  24. Qiu X, Chen G, Wang T. [Effects of huanglian jiedu decoction on free radicals metabolism and pathomorphism of the hippocampus in App/PS1 double transgenic mice]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2011;31:1379-82 pubmed
    To observe the effects of Huanglian Jiedu Decoction (HLJDT) on the metabolism of free radicals, the morphology and histopathology of hippocampal CA1 neurons in PS1/APP double transgenic mice of Alzheimer's disease (AD), and to study its ..
  25. Nam J, Moon J, Kim I, Lee M, Hong S, Ahn J, et al. Free radicals enzymatically triggered by Clonorchis sinensis excretory-secretory products cause NF-?B-mediated inflammation in human cholangiocarcinoma cells. Int J Parasitol. 2012;42:103-13 pubmed publisher
    ..that treatment of human cholangiocarcinoma cells with excretory-secretory products triggered increases in free radicals via a time-dependent activation of NADPH oxidase, xanthine oxidase and inducible nitric oxide synthase...
  26. Vejerano E, Lomnicki S, Dellinger B. Lifetime of combustion-generated environmentally persistent free radicals on Zn(II)O and other transition metal oxides. J Environ Monit. 2012;14:2803-6 pubmed
    Previous studies indicated that Environmentally Persistent Free Radicals (EPFRs) are formed in the post-flame, cool zone of combustion...
  27. Böhm F, Edge R, Truscott T. Interactions of dietary carotenoids with singlet oxygen (1O2) and free radicals: potential effects for human health. Acta Biochim Pol. 2012;59:27-30 pubmed
    ..The protection mechanisms involve both quenching of singlet oxygen and of damaging free radicals. The mechanisms for singlet oxygen quenching and protection against free radicals are quite different - indeed,..
  28. Visavadiya N, McEwen M, Pandya J, Sullivan P, Gwag B, Springer J. Antioxidant properties of Neu2000 on mitochondrial free radicals and oxidative damage. Toxicol In Vitro. 2013;27:788-97 pubmed publisher
    ..of reactive oxygen species and reactive nitrogen species (ROS/RNS) as well as its efficacy for reducing free radicals and oxidative stress/damage induced in spinal cord mitochondrial preparations...
  29. Soares C, Alves M, Bechara E. 1,4-Diamino-2-butanone, a wide-spectrum microbicide, yields reactive species by metal-catalyzed oxidation. Free Radic Biol Med. 2011;50:1760-70 pubmed publisher
    ..Our findings support the hypothesis that DAB toxicity to several pathogenic microorganisms previously described may involve not only reported inhibition of polyamine metabolism but also DAB pro-oxidant activity...
  30. Zhang Y, Stubbe J. Bacillus subtilis class Ib ribonucleotide reductase is a dimanganese(III)-tyrosyl radical enzyme. Biochemistry. 2011;50:5615-23 pubmed publisher
    ..5 Y(•)/?(2) and an activity of 318-363 nmol min(-1) mg(-1) (normalized for 1 Y(•)/?(2)). These data strongly suggest that the B. subtilis class Ib RNR is a Mn(III)(2)-Y(•) enzyme...
  31. Hekimi S, Lapointe J, Wen Y. Taking a "good" look at free radicals in the aging process. Trends Cell Biol. 2011;21:569-76 pubmed publisher
    ..This could generate the observed correlation between aging and ROS without implying that ROS damage is the earliest trigger or main cause of aging...
  32. Rivas Arreola M, Rocha Guzman N, Gallegos Infante J, Gonzalez Laredo R, Rosales Castro M, Bacon J, et al. Antioxidant activity of oak (Quercus) leaves infusions against free radicals and their cardioprotective potential. Pak J Biol Sci. 2010;13:537-45 pubmed
    ..sideroxyla, showing same effect as the control Captopril. From the results it is possible to postulate that not only chelating activity is important in these infusions, especially in Q. resinosa...
  33. Corcuera L, Amézqueta S, Arbillaga L, Vettorazzi A, Touriño S, Torres J, et al. A polyphenol-enriched cocoa extract reduces free radicals produced by mycotoxins. Food Chem Toxicol. 2012;50:989-95 pubmed publisher
    ..These results are coherent with the role of oxidative pathways in the mechanism of OTA and indicate that polyphenols extracted from cocoa may be good candidates as antioxidant agents...
  34. George N, Kumar T, Antony S, Jayanarayanan S, Paulose C. Effect of vitamin D3 in reducing metabolic and oxidative stress in the liver of streptozotocin-induced diabetic rats. Br J Nutr. 2012;108:1410-8 pubmed publisher
    ..of vitamin D(3) is mediated through VDR modulation, thereby improving signal transduction and controlling free radicals in the liver of diabetic rats...
  35. Chen R, Marchesan S, Evans R, Styan K, Such G, Postma A, et al. Photoinitiated alkyne-azide click and radical cross-linking reactions for the patterning of PEG hydrogels. Biomacromolecules. 2012;13:889-95 pubmed publisher
  36. Niatsetskaya Z, Sosunov S, Matsiukevich D, Utkina Sosunova I, Ratner V, Starkov A, et al. The oxygen free radicals originating from mitochondrial complex I contribute to oxidative brain injury following hypoxia-ischemia in neonatal mice. J Neurosci. 2012;32:3235-44 pubmed publisher
    ..This highlights a novel neuroprotective strategy against HI brain injury where the major therapeutic principle is a pharmacological attenuation, rather than an enhancement of mitochondrial oxidative metabolism during early reperfusion...
  37. Azam F, Prasad M, Thangavel N. Targeting oxidative stress component in the therapeutics of epilepsy. Curr Top Med Chem. 2012;12:994-1007 pubmed
    ..Oxidative injury produced by free radicals may play a role in the initiation and progression of epilepsy and, therapies aimed at reducing oxidative ..
  38. Halliwell B. Free radicals and antioxidants: updating a personal view. Nutr Rev. 2012;70:257-65 pubmed publisher
    ..Increasing endogenous antioxidant levels (e.g., by supplying "pro-oxidants") may be a better approach to therapeutics and disease prevention than consuming large doses of "dietary antioxidants."..
  39. Gu Y, Dee C, Shen J. Interaction of free radicals, matrix metalloproteinases and caveolin-1 impacts blood-brain barrier permeability. Front Biosci (Schol Ed). 2011;3:1216-31 pubmed
    b>Free radicals play an important role in cerebral ischemia-reperfusion injury...
  40. Zhang Q, Liu W. Complex biotransformations catalyzed by radical S-adenosylmethionine enzymes. J Biol Chem. 2011;286:30245-52 pubmed publisher
    ..g. the ThiC-catalyzed complex rearrangement reaction. The unique features and intriguing chemistries of these proteins thus demonstrate the remarkable versatility and sophistication of radical enzymology...
  41. Selivanov V, Cascante M, Friedman M, Schumaker M, Trucco M, Votyakova T. Multistationary and oscillatory modes of free radicals generation by the mitochondrial respiratory chain revealed by a bifurcation analysis. PLoS Comput Biol. 2012;8:e1002700 pubmed publisher
    ..Whereas multistationarity is an internal characteristic of the respiratory chain, the functional link of respiration with central metabolism creates oscillations, which can be understood as a means of auto-regulation of cell metabolism...
  42. Kovacic P, Somanathan R. Cell signaling and receptors in toxicity of advanced glycation end products (AGEs): ?-dicarbonyls, radicals, oxidative stress and antioxidants. J Recept Signal Transduct Res. 2011;31:332-9 pubmed publisher
    ..The toxic species have been related to illnesses and aging. Antioxidants alleviate the adverse effects...
  43. Gu Y, Xu Y, Law B, Qian S. The first characterization of free radicals formed from cellular COX-catalyzed peroxidation. Free Radic Biol Med. 2013;57:49-60 pubmed publisher
    ..studies using ovine COX along with spin trapping and the LC/ESR/MS technique have shown that certain exclusive free radicals are generated from different free radical reactions in DGLA and AA peroxidation...
  44. Chen L, Hsu C, Chiueh C, Lee W. Ferrous citrate up-regulates the NOS2 through nuclear translocation of NF?B induced by free radicals generation in mouse cerebral endothelial cells. PLoS ONE. 2012;7:e46239 pubmed publisher
    ..These findings highlight the molecular mechanism underlying FC-induced up-regulation of NOS2 in the mouse CEC...
  45. Böhm F, Edge R, Truscott G. Interactions of dietary carotenoids with activated (singlet) oxygen and free radicals: potential effects for human health. Mol Nutr Food Res. 2012;56:205-16 pubmed publisher
    ..Such redox-controlled reactions may lead to deleterious as well as beneficial health effects...
  46. Goh K, Kim S, Zard S. Free-radical variant for the synthesis of functionalized 1,5-diketones. Org Lett. 2013;15:4818-21 pubmed publisher
  47. Tentscher P, Arey J. On the nature of interactions of radicals with polar molecules. J Phys Chem A. 2013;117:12560-8 pubmed publisher
  48. Zahariou G, Chrysina M, Petrouleas V, Ioannidis N. Can we trap the S(3)Y(Z)· metalloradical intermediate during the S-state transitions of Photosystem II? An EPR investigation. FEBS Lett. 2014;588:1827-31 pubmed publisher
    ..The second with a splitting of ?80 G is tentatively assigned to S3YZ. The S3YZ EPR signal is weaker than the S2YZ one, and both are stable at cryogenic temperatures...
  49. Alwarsh S, Xu Y, Qian S, McIntosh M. Radical [1,3] Rearrangements of Breslow Intermediates. Angew Chem Int Ed Engl. 2016;55:355-8 pubmed publisher
    ..EPR experiments and computational analysis support a radical-based mechanism. Implications for thiamine-based enzymes are discussed. ..
  50. Moudache M, Colon M, Nerin C, Zaidi F. Phenolic content and antioxidant activity of olive by-products and antioxidant film containing olive leaf extract. Food Chem. 2016;212:521-7 pubmed publisher
    ..These multilayers were exposed to a gas stream enriched in free radicals to evaluate the scavenging capacity of both materials...
  51. Lebold K, Traber M. Interactions between ?-tocopherol, polyunsaturated fatty acids, and lipoxygenases during embryogenesis. Free Radic Biol Med. 2014;66:13-9 pubmed publisher
    ..The application and implication of such interactions are discussed in the context of ?-tocopherol requirements during embryogenesis. ..
  52. Wu C, Gao Q, Kjelgren R, Guo X, Wang M. Yields, phenolic profiles and antioxidant activities of Ziziphus jujube Mill. in response to different fertilization treatments. Molecules. 2013;18:12029-40 pubmed publisher
  53. Latham J, Barr I, Klinman J. At the confluence of ribosomally synthesized peptide modification and radical S-adenosylmethionine (SAM) enzymology. J Biol Chem. 2017;292:16397-16405 pubmed publisher
    ..The need for further work on this class of enzymes is emphasized, given the poorly understood roles performed by multiple, auxiliary iron-sulfur clusters and the paucity of protein X-ray structural data. ..