Top

Published in:

Open Access 01-12-2013 | Research

A central role for dityrosine crosslinking of Amyloid-β in Alzheimer’s disease

Authors: Youssra K Al-Hilaly, Thomas L Williams, Maris Stewart-Parker, Lenzie Ford, Eldhose Skaria, Michael Cole, William Grant Bucher, Kyle L Morris, Alaa Abdul Sada, Julian R Thorpe, Louise C Serpell

Published in: Acta Neuropathologica Communications | Issue 1/2013

Abstract

Background

Alzheimer’s disease (AD) is characterized by the deposition of insoluble amyloid plaques in the neuropil composed of highly stable, self-assembled Amyloid-beta (Aβ) fibrils. Copper has been implicated to play a role in Alzheimer’s disease. Dimers of Aβ have been isolated from AD brain and have been shown to be neurotoxic.

Results

We have investigated the formation of dityrosine cross-links in Aβ42 formed by covalent ortho-ortho coupling of two tyrosine residues under conditions of oxidative stress with elevated copper and shown that dityrosine can be formed in vitro in Aβ oligomers and fibrils and that these links further stabilize the fibrils. Dityrosine crosslinking was present in internalized Aβ in cell cultures treated with oligomeric Aβ42 using a specific antibody for dityrosine by immunogold labeling transmission electron microscopy. Results also revealed the prevalence of dityrosine crosslinks in amyloid plaques in brain tissue and in cerebrospinal fluid from AD patients.

Conclusions

Aβ dimers may be stabilized by dityrosine crosslinking. These results indicate that dityrosine cross-links may play an important role in the pathogenesis of Alzheimer’s disease and can be generated by reactive oxygen species catalyzed by Cu²⁺ ions. The observation of increased Aβ and dityrosine in CSF from AD patients suggests that this could be used as a potential biomarker of oxidative stress in AD.

Available only for authorised users

Selkoe DJ: The molecular pathology of Alzheimer’s disease. Neuron 1991, 6: 487–498. 10.1016/0896-6273(91)90052-2CrossRefPubMed

Rambaran RN, Serpell LC: Amyloid fibrils: abnormal protein assembly. Prion 2008, 2: 112–117. 10.4161/pri.2.3.7488PubMedCentralCrossRefPubMed

Hardy J, Selkoe DJ: The amyloid hypothesis of Alzheimer’s disease: progress and problems on the road to therapeutics. Science 2002, 297: 353–356. 10.1126/science.1072994CrossRefPubMed

Luhrs T, Ritter C, Adrian M, Riek-Loher D, Bohrmann B, Dobeli H, Schubert D, Riek R: 3D structure of Alzheimer’s amyloid-beta(1–42) fibrils. Proc Natl Acad Sci USA 2005, 102: 17342–17347. 10.1073/pnas.0506723102PubMedCentralCrossRefPubMed

Hensley K, Maidt ML, Yu Z, Sang H, Markesbery WR, Floyd RA: Electrochemical analysis of protein nitrotyrosine and dityrosine in the Alzheimer brain indicates region-specific accumulation. J Neurosci 1998, 18: 8126–8132.PubMed

Bush AI, Curtain CC: Twenty years of metallo-neurobiology: where to now? Eur Biophys J 2008, 37: 241–245. 10.1007/s00249-007-0228-1CrossRefPubMed

Ali FE, Barnham KJ, Barrow CJ, Separovic F: Copper catalysed oxidation of amino acids and Alzheimer’s disease. Lett Pept Sci 2003, 10: 405–412. 10.1007/BF02442571CrossRef

Sarell CJ, Wilkinson SR, Viles JH: Substoichiometric levels of Cu2+ ions accelerate the kinetics of fiber formation and promote cell toxicity of amyloid-Œ ≤ from Alzheimer disease. J Biol Chem 2010, 285: 41533–41540. 10.1074/jbc.M110.171355PubMedCentralCrossRefPubMed

Huang X, Moir RD, Tanzi RE, Bush AI, Rogers JT: Redox-active metals, oxidative stress, and Alzheimer’s disease pathology. Ann Ny Acad Sci 2004, 1012: 153–163. 10.1196/annals.1306.012CrossRefPubMed

10.

Bush AI: The metallobiology of Alzheimer's disease. Trends Neurosci 2003, 26: 207–214. 10.1016/S0166-2236(03)00067-5CrossRefPubMed

11.

Levine RL, Stadtman ER: Oxidative modification of proteins during aging. Exp Gerontol 2001, 36: 1495–1502. 10.1016/S0531-5565(01)00135-8CrossRefPubMed

12.

Lynch T, Cherny RA, Bush AI: Oxidative processes in Alzheimer’s disease: the role of Aβ-metal interactions. Exp Gerontol 2000, 35: 445–451. 10.1016/S0531-5565(00)00112-1CrossRefPubMed

13.

Butterfield DA, Reed T, Newman SF, Sultana R: Roles of amyloid beta-peptide-associated oxidative stress and brain protein modifications in the pathogenesis of Alzheimer’s disease and mild cognitive impairment. Free Radic Biol Med 2007, 43: 658–677. 10.1016/j.freeradbiomed.2007.05.037PubMedCentralCrossRefPubMed

14.

Double KL, Dedov VN, Fedorow H, Kettle E, Halliday GM, Garner B, Brunk UT: The comparative biology of neuromelanin and lipofuscin in the human brain. Cell Mol Life Sci 2008, 65: 1669–1682. 10.1007/s00018-008-7581-9CrossRefPubMed

15.

Lovell MA, Robertson JD, Teesdale WJ, Campbell JL, Markesbery WR: Copper, iron and zinc in Alzheimer’s disease senile plaques. J Neurol Sci 1998, 158: 47–52. 10.1016/S0022-510X(98)00092-6CrossRefPubMed

16.

Huang X, Atwood CS, Hartshorn MA, Multhaup G, Goldstein LE, Scarpa RC, Cuajungco MP, Gray DN, Lim J, Moir RD, et al.: The A beta peptide of Alzheimer’s disease directly produces hydrogen peroxide through metal ion reduction. Biochemistry-Us 1999, 38: 7609–7616. 10.1021/bi990438fCrossRef

17.

Atwood CS, Moir RD, Huang X, Scarpa RC, Bacarra NME, Romano DM, Hartshorn MA, Tanzi RE, Bush AI: Dramatic aggregation of Alzheimer AŒ ≤ by Cu(II) is induced by conditions representing physiological acidosis. J Biol Chem 1998, 273: 12817–12826. 10.1074/jbc.273.21.12817CrossRefPubMed

18.

Souza JM, Giasson BI, Chen Q, Lee VM, Ischiropoulos H: Dityrosine cross-linking promotes formation of stable alpha -synuclein polymers. Implication of nitrative and oxidative stress in the pathogenesis of neurodegenerative synucleinopathies. J Biol Chem 2000, 275: 18344–18349. 10.1074/jbc.M000206200CrossRefPubMed

19.

Yoburn JC, Tian W, Brower JO, Nowick JS, Glabe CG, Van Vranken DL: Dityrosine cross-linked Abeta peptides: fibrillar beta-structure in Abeta(1–40) is conducive to formation of dityrosine cross-links but a dityrosine cross-link in Abeta(8–14) does not induce beta-structure. Chem Res Toxicol 2003, 16: 531–535. 10.1021/tx025666gCrossRefPubMed

20.

Atwood CS, Perry G, Zeng H, Kato Y, Jones WD, Ling KQ, Huang X, Moir RD, Wang D, Sayre LM, et al.: Copper mediates dityrosine cross-linking of Alzheimer’s amyloid-beta. Biochemistry-Us 2004, 43: 560–568. 10.1021/bi0358824CrossRef

21.

Giulivi C, Traaseth NJ, Davies KJ: Tyrosine oxidation products: analysis and biological relevance. Amino Acids 2003, 25: 227–232. 10.1007/s00726-003-0013-0CrossRefPubMed

22.

Smith DP, Smith DG, Curtain CC, Boas JF, Pilbrow JR, Ciccotosto GD, Lau TL, Tew DJ, Perez K, Wade JD, et al.: Copper-mediated amyloid-beta toxicity is associated with an intermolecular histidine bridge. J Biol Chem 2006, 281: 15145–15154. 10.1074/jbc.M600417200CrossRefPubMed

23.

DiMarco T, Giulivi C: Current analytical methods for the detection of dityrosine, a biomarker of oxidative stress, in biological samples. Mass Spectrom Rev 2007, 26: 108–120. 10.1002/mas.20109CrossRefPubMed

24.

Amado R, Aeschbach R, Neukom H: Dityrosine - invitro production and characterization. Methods Enzymol 1984, 107: 377–388.CrossRefPubMed

25.

Giulivi C, Davies KJ: Dityrosine: a marker for oxidatively modified proteins and selective proteolysis. Methods Enzymol 1994, 233: 363–371.CrossRefPubMed

26.

Guo ZW, Salamonczyk GM, Han K, Machiya K, Sih CJ: Enzymatic oxidative phenolic coupling. J Org Chem 1997, 62: 6700–6701. 10.1021/jo970995cCrossRef

27.

Lee DI, Hwang S, Choi JY, Ahn IS, Lee CH: A convenient preparation of dityrosine via Mn(III)-mediated oxidation of tyrosine. Process Biochem 2008, 43: 999–1003. 10.1016/j.procbio.2008.04.020CrossRef

28.

Skaff O, Jolliffe KA, Hutton CA: Synthesis of the side chain cross-linked tyrosine oligomers dityrosine, trityrosine, and pulcherosine. J Org Chem 2005, 70: 7353–7363. 10.1021/jo051076mCrossRefPubMed

29.

Jacob JS, Cistola DP, Hsu FF, Muzaffar S, Mueller DM, Hazen SL, Heinecke JW: Human phagocytes employ the myeloperoxidase-hydrogen peroxide system to synthesize dityrosine, trityrosine, pulcherosine, and isodityrosine by a tyrosyl radical-dependent pathway. J Biol Chem 1996, 271: 19950–19956. 10.1074/jbc.271.33.19950CrossRefPubMed

30.

Williams TL, Day IJ, Serpell LC: The effect of Alzheimer’s Abeta aggregation state on the permeation of biomimetic lipid vesicles. Langmuir 2010, 26: 17260–17268. 10.1021/la101581gCrossRefPubMed

31.

Kato Y, Wu X, Naito M, Nomura H, Kitamoto N, Osawa T: Immunochemical detection of protein dityrosine in atherosclerotic lesion of apo-E-deficient mice using a novel monoclonal antibody. Biochem Biophys Res Commun 2000, 275: 11–15. 10.1006/bbrc.2000.3265CrossRefPubMed

32.

Agholme L, Hallbeck M, Benedikz E, Marcusson J, Kagedal K: Amyloid-beta secretion, generation, and lysosomal sequestration in response to proteasome inhibition: involvement of autophagy. J Alzheimers Dis 2012, 31: 343–358.PubMed

33.

Soura V, Stewart-Parker M, Williams TL, Ratnayaka A, Atherton J, Gorringe K, Tuffin J, Darwent E, Rambaran R, Klein W, et al.: Visualization of co-localization in Abeta42-administered neuroblastoma cells reveals lysosome damage and autophagosome accumulation related to cell death. Biochem J 2012, 441: 579–590. 10.1042/BJ20110749CrossRefPubMed

34.

Thorpe JR, Morley SJ, Rulten SL: Utilizing the peptidyl-prolyl cis-trans isomerase Pin1 as a probe of its phosphorylated target proteins: Examples of binding to nuclear proteins in a human kidney cell line and to tau in Alzheimer’s diseased brain. J Histochem Cytochem 2001, 49: 97–107. 10.1177/002215540104900110CrossRefPubMed

35.

Thorpe JR: The application of LR gold resin for immunogold labeling. Methods Mol Biol 1999, 117: 99–110.PubMed

36.

Malencik DA, Sprouse JF, Swanson CA, Anderson SR: Dityrosine: Preparation, isolation, and analysis. Anal Biochem 1996, 242: 202–213. 10.1006/abio.1996.0454CrossRefPubMed

37.

Paravastu AK, Leapman RD, Yau WM, Tycko R: Molecular structural basis for polymorphism in Alzheimer’s beta-amyloid fibrils. Proc Natl Acad Sci USA 2008, 105: 18349–18354. 10.1073/pnas.0806270105PubMedCentralCrossRefPubMed

38.

Roychaudhuri R, Yang M, Hoshi MM, Teplow DB: Amyloid Œ ≤ −protein assembly and Alzheimer disease. J Biol Chem 2009, 284: 4749–4753.PubMedCentralCrossRefPubMed

39.

Walsh DM, Klyubin I, Fadeeva JV, Cullen WK, Anwyl R, Wolfe MS, Rowan MJ, Selkoe DJ: Naturally secreted oligomers of amyloid Œ ≤ protein potently inhibit hippocampal long-term potentiation in vivo. Nature 2002, 416: 535–539. 10.1038/416535aCrossRefPubMed

40.

Kuo YM, Emmerling MR, Vigo-Pelfrey C, Kasunic TC, Kirkpatrick JB, Murdoch GH, Ball MJ, Roher AE: Water-soluble Abeta (N-40, N-42) oligomers in normal and Alzheimer disease brains. J Biol Chem 1996, 271: 4077–4081. 10.1074/jbc.271.8.4077CrossRefPubMed

41.

Shankar GM, Li S, Mehta TH, Garcia-Munoz A, Shepardson NE, Smith I, Brett FM, Farrell MA, Rowan MJ, Lemere CA, et al.: Amyloid-beta protein dimers isolated directly from Alzheimer’s brains impair synaptic plasticity and memory. Nature medicine 2008, 14: 837–842. 10.1038/nm1782PubMedCentralCrossRefPubMed

42.

Kok WM, Cottam JM, Ciccotosto GD, Miles LA, Karas JA, Scanlon DB, Roberts BR, Parker MW, Cappai R, Barnham KJ, Hutton CA: Synthetic dityrosine-linked beta-amyloid dimers form stable, soluble neurotoxic oligomers. Chem Sci 2013, 4: 4449–4454. 10.1039/c3sc22295kCrossRef

43.

Marshall KE, Serpell LC: Structural integrity of beta-sheet assembly. Biochem Soc Trans 2009, 37: 671–676. 10.1042/BST0370671CrossRefPubMed

44.

Bitan G, Kirkitadze MD, Lomakin A, Vollers SS, Benedek GB, Teplow DB: Amyloid beta -protein (Abeta) assembly: Abeta 40 and Abeta 42 oligomerize through distinct pathways. Proc Natl Acad Sci USA 2003, 100: 330–335. 10.1073/pnas.222681699PubMedCentralCrossRefPubMed

45.

Smith DP, Ciccotosto GD, Tew DJ, Fodero-Tavoletti MT, Johanssen T, Masters CL, Barnham KJ, Cappai R: Concentration dependent Cu2+ induced aggregation and dityrosine formation of the Alzheimer’s disease amyloid-beta peptide. Biochemistry-Us 2007, 46: 2881–2891. 10.1021/bi0620961CrossRef

46.

Huang X, Cuajungco MP, Atwood CS, Hartshorn MA, Tyndall JDA, Hanson GR, Stokes KC, Leopold M, Multhaup G, Goldstein LE, et al.: Cu(II) Potentiation of Alzheimer Aβ Neurotoxicity: CORRELATION WITH CELL-FREE HYDROGEN PEROXIDE PRODUCTION AND METAL REDUCTION. J Biol Chem 1999, 274: 37111–37116. 10.1074/jbc.274.52.37111CrossRefPubMed

47.

Syme CD, Nadal RC, Rigby SE, Viles JH: Copper binding to the amyloid-beta (Abeta) peptide associated with Alzheimer’s disease: folding, coordination geometry, pH dependence, stoichiometry, and affinity of Abeta-(1–28): insights from a range of complementary spectroscopic techniques. J Biol Chem 2004, 279: 18169–18177. 10.1074/jbc.M313572200CrossRefPubMed

48.

Atwood CS, Scarpa RC, Huang XD, Moir RD, Jones WD, Fairlie DP, Tanzi RE, Bush AI: Characterization of copper interactions with Alzheimer amyloid beta peptides: identification of an attomolar-affinity copper binding site on amyloid beta 1–42. J Neurochem 2000, 75: 1219–1233.CrossRefPubMed

49.

Tickler AK, Smith DG, Ciccotosto GD, Tew DJ, Curtain CC, Carrington D, Masters CL, Bush AI, Cherny RA, Cappai R, et al.: Methylation of the imidazole side chains of the Alzheimer disease amyloid-beta peptide results in abolition of superoxide dismutase-like structures and inhibition of neurotoxicity. J Biol Chem 2005, 280: 13355–13363. 10.1074/jbc.M414178200CrossRefPubMed

50.

Curtain CC, Ali F, Volitakis I, Cherny RA, Norton RS, Beyreuther K, Barrow CJ, Masters CL, Bush AI, Barnham KJ: Alzheimer’s disease amyloid-beta binds copper and zinc to generate an allosterically ordered membrane-penetrating structure containing superoxide dismutase-like subunits. J Biol Chem 2001, 276: 20466–20473. 10.1074/jbc.M100175200CrossRefPubMed

51.

Maiti NC, Jiang DL, Wain AJ, Patel S, Dinh KL, Zhou FM: Mechanistic studies of Cu(II) binding to amyloid-beta peptides and the fluorescence and redox behaviors of the resulting complexes. J Phys Chem B 2008, 112: 8406–8411. 10.1021/jp802038pCrossRefPubMed

52.

Marquez LA, Dunford HB: Kinetics of oxidation of tyrosine and dityrosine by myeloperoxidase compounds I and II. Implications for lipoprotein peroxidation studies. J Biol Chem 1995, 270: 30434–30440. 10.1074/jbc.270.51.30434CrossRefPubMed

53.

Reynolds WF, Rhees J, Maciejewski D, Paladino T, Sieburg H, Maki RA, Masliah E: Myeloperoxidase polymorphism is associated with gender specific risk for Alzheimer’s disease. Exp Neurol 1999, 155: 31–41. 10.1006/exnr.1998.6977CrossRefPubMed

54.

Zheng L, Roberg K, Jerhammar F, Marcusson J, Terman A: Autophagy of amyloid beta-protein in differentiated neuroblastoma cells exposed to oxidative stress. Neurosci Lett 2006, 394: 184–189. 10.1016/j.neulet.2005.10.035CrossRefPubMed

55.

Yu WH, Cuervo AM, Kumar A, Peterhoff CM, Schmidt SD, Lee JH, Mohan PS, Mercken M, Farmery MR, Tjernberg LO, et al.: Macroautophagy–a novel Beta-amyloid peptide-generating pathway activated in Alzheimer’s disease. J Cell Biol 2005, 171: 87–98. 10.1083/jcb.200505082PubMedCentralCrossRefPubMed

56.

Yang AJ, Chandswangbhuvana D, Margol L, Glabe CG: Loss of endosomal/lysosomal membrane impermeability is an early event in amyloid A beta 1–42 pathogenesis. J Neurosci Res 1998, 52: 691–698. 10.1002/(SICI)1097-4547(19980615)52:6<691::AID-JNR8>3.0.CO;2-3CrossRefPubMed

57.

Barnham KJ, Haeffner F, Ciccotosto GD, Curtain CC, Tew D, Mavros C, Beyreuther K, Carrington D, Masters CL, Cherny RA, et al.: Tyrosine gated electron transfer is key to the toxic mechanism of Alzheimer’s disease beta-amyloid. Faseb J 2004, 18: 1427–1429.PubMed

58.

Chance B, Sies H, Boveris A: Hydroperoxide metabolism in mammalian organs. Physiol Rev 1979, 59: 527–605.PubMed

59.

Harman D: Aging: a theory based on free radical and radiation chemistry. Sci Aging Knowledge Environ 2002, 2002: cp14.

60.

Murakami K, Shimizu T: Cytoplasmic superoxide radical: a possible contributing factor to intracellular Abeta oligomerization in Alzheimer disease. Comm Integ Biol 2012, 5: 255–258. 10.4161/cib.19548CrossRef

61.

Umeda T, Tomiyama T, Sakama N, Tanaka S, Lambert MP, Klein WL, Mori H: Intraneuronal amyloid beta oligomers cause cell death via endoplasmic reticulum stress, endosomal/lysosomal leakage, and mitochondrial dysfunction in vivo. J Neurosci Res 2011, 89: 1031–1042. 10.1002/jnr.22640CrossRefPubMed

62.

Misonou H, Morishima-Kawashima M, Ihara Y: Oxidative stress induces intracellular accumulation of amyloid Œ ≤ − protein (AŒ≤) in human neuroblastoma cells. Biochemistry-Us 2000, 39: 6951–6959. 10.1021/bi000169pCrossRef

63.

Kurz T, Terman A, Gustafsson B, Brunk UT: Lysosomes and oxidative stress in aging and apoptosis. Biochim Biophys Acta Gen Subj 2008, 1780: 1291–1303. 10.1016/j.bbagen.2008.01.009CrossRef

64.

Friedrich RP, Tepper K, Ronicke R, Soom M, Westermann M, Reymann K, Kaether C, Fandrich M: Mechanism of amyloid plaque formation suggests an intracellular basis of Abeta pathogenicity. Proc Natl Acad Sci USA 2010, 107: 1942–1947. 10.1073/pnas.0904532106PubMedCentralCrossRefPubMed

65.

Roher AE, O’Chaney M, Kuo Y, Webster SD, Stine WB, Haverkamp LJ, Woods AS, Cotter RJ, Tuohy JM, Krafft GA, et al.: Morphology and toxicity of Ab-(1–42) dimer derived from neuritic and vascular amyloid deposits of Alzheimer’s disease. J Biol Chem 1996, 271: 20631–20635. 10.1074/jbc.271.34.20631CrossRefPubMed

66.

Cherny RA, Atwood CS, Xilinas ME, Gray DN, Jones WD, McLean CA, Barnham KJ, Volitakis I, Fraser FW, Kim YS, et al.: Treatment with a copper-zinc chelator markedly and rapidly inhibits beta-amyloid accumulation in Alzheimer’s disease transgenic mice. Neuron 2001, 30: 665–676. 10.1016/S0896-6273(01)00317-8CrossRefPubMed

67.

Ritchie CW, Bush AI, Mackinnon A, Macfarlane S, Mastwyk M, MacGregor L, Kiers L, Cherny R, Li QX, Tammer A, et al.: Metal-protein attenuation with iodochlorhydroxyquin (clioquinol) targeting Abeta amyloid deposition and toxicity in Alzheimer disease: a pilot phase 2 clinical trial. Arch Neurol 2003, 60: 1685–1691. 10.1001/archneur.60.12.1685CrossRefPubMed

68.

Ahmed N, Ahmed U, Thornalley PJ, Hager K, Fleischer G, Munch G: Protein glycation, oxidation and nitration adduct residues and free adducts of cerebrospinal fluid in Alzheimer’s disease and link to cognitive impairment. J Neurochem 2005, 92: 255–263. 10.1111/j.1471-4159.2004.02864.xCrossRefPubMed

69.

Abdelrahim M, Morris E, Carver J, Facchina S, White A, Verma A: Liquid chromatographic assay of dityrosine in human cerebrospinal fluid. J Chromatogr B 1997, 696: 175–182. 10.1016/S0378-4347(97)00248-XCrossRef

70.

Maruyama M, Arai H, Sugita M, Tanji H, Higuchi M, Okamura N, Matsui T, Higuchi S, Matsushita S, Yoshida H, Sasaki H: Cerebrospinal fluid amyloid beta(1–42) levels in the mild cognitive impairment stage of Alzheimer’s disease. Exp Neurol 2001, 172: 433–436. 10.1006/exnr.2001.7814CrossRefPubMed

Title: A central role for dityrosine crosslinking of Amyloid-β in Alzheimer’s disease
Authors: Youssra K Al-Hilaly
Thomas L Williams
Maris Stewart-Parker
Lenzie Ford
Eldhose Skaria
Michael Cole
William Grant Bucher
Kyle L Morris
Alaa Abdul Sada
Julian R Thorpe
Louise C Serpell
Publication date: 01-12-2013
Publisher: BioMed Central
Published in: Acta Neuropathologica Communications / Issue 1/2013
Electronic ISSN: 2051-5960
DOI: https://doi.org/10.1186/2051-5960-1-83

At a glance: The STEP trials

Springer Medicine

A central role for dityrosine crosslinking of Amyloid-β in Alzheimer’s disease

Abstract

Background

Results

Conclusions

At a glance: The STEP trials

Springer Medicine

Abstract

Background

Results

Conclusions

Please log in to get access to this content

Other articles of this Issue 1/2013

Increased mitochondrial activity in a novel IDH1-R132H mutant human oligodendroglioma xenograft model: in situ detection of 2-HG and α-KG

Glial scaffold required for cerebellar granule cell migration is dependent on dystroglycan function as a receptor for basement membrane proteins

Double-labelling immunohistochemistry for MGMT and a “cocktail” of non-tumourous elements is a reliable, quick and easy technique for inferring methylation status in glioblastomas and other primary brain tumours

Extensive aggregation of α-synuclein and tau in juvenile-onset neuroaxonal dystrophy: an autopsied individual with a novel mutation in the PLA2G6 gene-splicing site

The influence of DNA repair on neurological degeneration, cachexia, skin cancer and internal neoplasms: autopsy report of four xeroderma pigmentosum patients (XP-A, XP-C and XP-D)

Lipid accumulation, lipid oxidation, and low plasma levels of acquired antibodies against oxidized lipids associate with degeneration and rupture of the intracranial aneurysm wall