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Long-duration epilepsy affects cell morphology and glutamatergic synapses in type IIB focal cortical dysplasia

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Abstract

To investigate hypothesized effects of severe epilepsy on malformed cortex, we analyzed surgical samples from eight patients with type IIB focal cortical dysplasia (FCD) in comparison with samples from nine non-dysplastic controls. We investigated, using stereological quantification methods, where appropriate, dysplastic neurons, neuronal density, balloon cells, glia, glutamatergic synaptic input, and the expression of N-methyl-d-aspartate (NMDA) receptor subunits and associated membrane-associated guanylate kinase (MAGUK). In all FCD patients, the dysplastic areas giving rise to epileptic discharges were characterized by larger dysmorphic neurons, reduced neuronal density, and increased glutamatergic inputs, compared to adjacent areas with normal cytology. The duration of epilepsy was found to correlate directly (a) with dysmorphic neuron size, (b) reduced neuronal cell density, and (c) extent of reactive gliosis in epileptogenic/dysplastic areas. Consistent with increased glutamatergic input, western blot revealed that NMDA regulatory subunits and related MAGUK proteins were up-regulated in epileptogenic/dysplastic areas of all FCD patients examined. Taken together, these results support the hypothesis that epilepsy itself alters morphology—and probably also function—in the malformed epileptic brain. They also suggest that glutamate/NMDA/MAGUK dysregulation might be the intracellular trigger that modifies brain morphology and induces cell death.

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References

  1. Aarts MM, Tymianski M (2004) Molecular mechanisms underlying specificity of excitotoxic signaling in neurons. Curr Mol Med 4:137–147

    Article  PubMed  CAS  Google Scholar 

  2. Alonso-Nanclares L, De Felipe J (2005) Vesicular glutamate transporter 1 immunostaining in the normal and epileptic human cerebral cortex. Neuroscience 134:59–68

    Article  PubMed  CAS  Google Scholar 

  3. Alonso-Nanclares L, Garbelli R, Sola RG et al (2005) Microanatomy of the dysplastic neocortex from epileptic patients. Brain 128:158–173

    Article  PubMed  CAS  Google Scholar 

  4. Andres M, Andre VM, Nguyen S et al (2005) Human cortical dysplasia and epilepsy: an ontogenetic hypothesis based on volumetric MRI and NeuN neuronal density and size measurements. Cereb Cortex 15:194–210

    Article  PubMed  Google Scholar 

  5. Barkovich AJ, Guerrini R, Kuzniecky RI, Jackson GD, Dobyns WB (2012) A developmental and genetic classification for malformations of cortical development: update. Brain 135:1348–1369

    Article  PubMed  Google Scholar 

  6. Barkovich AJ, Kuzniecky RI, Jackson GD, Guerrini R, Dobyns WB (2001) Classification system for malformations of cortical development: update 2001. Neurology 57:2168–2178

    Article  PubMed  CAS  Google Scholar 

  7. Battaglia G, Arcelli P, Granata T et al (1996) Neuronal migration disorders and epilepsy: a morphological analysis of three surgically treated patients. Epilepsy Res 26:49–58

    Article  PubMed  CAS  Google Scholar 

  8. Baybis M, Yu J, Lee A et al (2004) mTOR cascade activation distinguishes tubers from focal cortical dysplasia. Ann Neurol 56:478–487

    Article  PubMed  CAS  Google Scholar 

  9. Becker AJ, Urbach H, Scheffler B et al (2002) Focal cortical dysplasia of Taylor’s balloon cell type: mutational analysis of the TSC1 gene indicates a pathogenic relationship to tuberous sclerosis. Ann Neurol 52:29–37

    Article  PubMed  CAS  Google Scholar 

  10. Blümcke I, Thom M, Aronica E et al (2011) The clinicopathologic spectrum of focal cortical dysplasias: a consensus classification proposed by an ad hoc task force of the ILAE diagnostic methods commission. Epilepsia 52:158–174

    Article  PubMed  Google Scholar 

  11. Bothwell S, Meredith GE, Phillips J et al (2001) Neuronal hypertrophy in the neocortex of patients with temporal lobe epilepsy. J Neurosci 21:4789–4800

    PubMed  CAS  Google Scholar 

  12. Chamberlain WA, Prayson RA (2008) Focal cortical dysplasia type II (malformations of cortical development) aberrantly expresses apoptotic proteins. Appl Immunohistochem Mol Morphol 16:471–476

    Article  PubMed  CAS  Google Scholar 

  13. Colciaghi F, Finardi A, Frasca A et al (2011) Status epilepticus-induced pathologic plasticity in a rat model of focal cortical dysplasia. Brain 134:2828–2843

    Article  PubMed  Google Scholar 

  14. Crino PB, Duhaime AC, Baltuch G, White R (2001) Differential expression of glutamate and GABA-A receptor subunit m-RNA in cortical dysplasia. Neurology 56:906–913

    Article  PubMed  CAS  Google Scholar 

  15. da Silva AV, Houzel JC, Targas Yacubian EM et al (2006) Dysmorphic neurons in patients with temporal lobe epilepsy. Brain Res 1072:200–207

    Article  PubMed  Google Scholar 

  16. Engel J Jr, Van Ness PC, Rasmussen TB (1993) Outcome with respect to epileptic seizures. In: J Engel Jr (ed) Surgical treatment of the epilepsies, 2nd edn. Raven Press Ltd, NY, pp 609–621

  17. Fauser S, Huppertz HJ, Bast T et al (2006) Clinical characteristics in focal cortical dysplasia: a retrospective evaluation in a series of 120 patients. Brain 129:1907–1916

    Article  PubMed  Google Scholar 

  18. Finardi A, Gardoni F, Bassanini S et al (2006) NMDA receptor composition differs among anatomically diverse malformations of cortical development. J Neuropathol Exp Neurol 65:883–893

    Article  PubMed  CAS  Google Scholar 

  19. Garbelli R, Munari C, De Biasi S et al (1999) Taylor’s cortical dysplasia: a confocal and ultrastructural immunohistochemical study. Brain Pathol 9:445–461

    Article  PubMed  CAS  Google Scholar 

  20. Gardoni F, Mauceri D, Malinverno M et al (2009) Decreased NR2B subunit synaptic levels cause impaired long-term potentiation but not long-term depression. J Neurosci 29:669–677

    Article  PubMed  CAS  Google Scholar 

  21. Glaser JR, Glaser EM (1990) Neuron imaging with Neurolucida—a PC-based system for image combining microscopy. Comput Med Imaging Graph 14:307–317

    Article  PubMed  CAS  Google Scholar 

  22. Hardiman O, Burke T, Phillips J et al (1998) Microdysgenesis in resected temporal neocortex: incidence and clinical significance in focal epilepsy. Neurology 38:1041–1047

    Article  Google Scholar 

  23. Hardingham GE, Bading H (2010) Synaptic versus extrasynaptic NMDA receptor signalling: implications for neurodegenerative disorders. Nat Rev Neurosci 11:682–696

    Article  PubMed  CAS  Google Scholar 

  24. Hardingham GE, Fukunaga Y, Bading H (2002) Extrasynaptic NMDARs oppose synaptic NMDARs by triggering CREB shut-off and cell death pathways. Nat Neurosi 5:405–414

    CAS  Google Scholar 

  25. Hur EE, Zaborszky L (2005) Vglut2 afferents to the medial prefrontal and primary somatosensory cortices: a combined retrograde tracing in situ hybridization study. J Comp Neurol 483:351–373

    Article  PubMed  Google Scholar 

  26. Kim E, Sheng M (2004) PDZ domain proteins of synapses. Nat Rev Neurosi 5:771–781

    Article  CAS  Google Scholar 

  27. Lamparello P, Baybis M, Pollard J et al (2007) Developmental lineage of cell types in cortical dysplasia with balloon cells. Brain 130:2267–2276

    Article  PubMed  Google Scholar 

  28. Leiphart JW, Peacock WJ, Mathern GW (2001) Lobar and multilobar resections for medically intractable pediatric epilepsy. Pediatr Neurosurg 34:311–318

    Article  PubMed  CAS  Google Scholar 

  29. Lerner JT, Salamon N, Hauptman JS et al (2009) Assessment and surgical outcomes for mild type I and severe type II cortical dysplasia: a critical review and the UCLA experience. Epilepsia 50:1310–1335

    Article  PubMed  Google Scholar 

  30. Liou AK, Clark RS, Henshall DC, Yin XM, Chen J (2003) To die or not to die for neurons in ischemia, traumatic brain injury and epilepsy: a review on the stress-activated signaling pathways and apoptotic pathways. Prog Neurobiol 69:103–142

    Article  PubMed  CAS  Google Scholar 

  31. Mischel PS, Nguyen LP, Vinters HV (1995) Cerebral cortical dysplasia associated with pediatric epilepsy. Review of neuropathologic features and proposal for a grading system. J Neuropathol Exp Neurol 54:137–153

    Article  PubMed  CAS  Google Scholar 

  32. Möddel G, Jacobson B, Ying Z et al (2005) NMDA receptor NR2B subunit contributes to epileptogenesis in human cortical dysplasia. Brain Res 1046:10–23

    Article  PubMed  Google Scholar 

  33. Monyer H, Burnashev N, Laurie DJ, Sakmann B, Seeburg PH (1994) Developmental and regional expression in the rat brain and functional properties of four NMDA receptors. Neuron 12:529–540

    Article  PubMed  CAS  Google Scholar 

  34. Mühlebner A, Coras R, Kobow K et al (2012) Neuropathologic measurements in focal cortical dysplasias: validation of the ILAE 2011 classification system and diagnostic implications for MRI. Acta Neuropathol 123:259–272

    Article  PubMed  Google Scholar 

  35. Najm IM, Ying Z, Babb T et al (2000) Epileptogenicity correlated with increased N-Methyl-D-Aspartate receptor subunit NR2A/B in human focal cortical dysplasia. Epilepsia 41:971–976

    Article  PubMed  CAS  Google Scholar 

  36. Nakamura K, Hioki H, Fujiyama F, Kaneko T (2005) Postnatal changes of vesicular glutamate transporter (VGluT)1 and VGluT2 immunoreactivities and their colocalization in the mouse forebrain. J Comp Neurol. 492:263–288

    Article  PubMed  CAS  Google Scholar 

  37. Orlova KA, Tsai V, Baybis M et al (2010) Early progenitor cell marker expression distinguishes type II from type I focal cortical dysplasias. J Neuropathol Exp Neurol 69:850–863

    Article  PubMed  CAS  Google Scholar 

  38. Palmini A, Gambardella A, Andermann F et al (1995) Intrinsic epileptogenicity of human dysplastic cortex as suggested by corticography and surgical results. Ann Neurol 37:476–487

    Article  PubMed  CAS  Google Scholar 

  39. Palmini A, Najm I, Avanzini G et al (2004) Terminology and classification of the cortical dysplasias. Neurology 62:S2–S8

    Article  PubMed  CAS  Google Scholar 

  40. Regalado MP, Terry-Lorenzo RT, Waites CL, Garner CC, Malenka RC (2006) Transsynaptic signaling by postsynaptic synapse-associated protein 97. J Neurosci 26:2343–2357

    Article  PubMed  CAS  Google Scholar 

  41. Reuver SM, Garner CC (1998) E-cadherin mediated cell adhesion recruits SAP97 into the cortical cytoskeleton. J Cell Sci 111:1071–1080

    PubMed  CAS  Google Scholar 

  42. Sattler R, Xiong Z, Lu WY, Hafner M, MacDonald JF, Tymianski M (1999) Specific coupling of NMDA receptor activation to nitric oxide neurotoxicity by PSD-95 protein. Science 284:1845–1848

    Article  PubMed  CAS  Google Scholar 

  43. Spreafico R, Battaglia G, Arcelli P et al (1998) Cortical dysplasia: an immunocytochemical study of three patients. Neurology 50:27–36

    Article  PubMed  CAS  Google Scholar 

  44. Tassi L, Colombo N, Garbelli R et al (2002) Focal cortical dysplasia: neuropathological subtypes, EEG, neuroimaging and surgical outcome. Brain 125:1719–1732

    Article  PubMed  CAS  Google Scholar 

  45. Tassi L, Pasquier B, Minotti L et al (2001) Cortical dysplasia: electroclinical, imaging, and neuropathologic study of 13 patients. Epilepsia 42:1112–1123

    Article  PubMed  CAS  Google Scholar 

  46. Taylor DC, Falconer MA, Bruton CJ, Corsellis JA (1971) Focal dysplasia of the cerebral cortex in epilepsy. J Neurol Neurosurg Psychiatry 34:369–387

    Article  PubMed  CAS  Google Scholar 

  47. Thom M, Martinian L, Sen A, Cross JH, Harding BN, Sisodiya SM (2005) Cortical neuronal densities and lamination in focal cortical dysplasia. Acta Neuropathol 110:383–392

    Article  PubMed  CAS  Google Scholar 

  48. van der Hel WS, Verlinde SA, Meijer DH et al (2009) Hippocampal distribution of vesicular glutamate transporter 1 in patients with temporal lobe epilepsy. Epilepsia 50:1717–1728

    Article  PubMed  Google Scholar 

  49. Vercelli A, Mereuta OM, Garbossa D et al (2008) Human mesenchymal stem cell transplantation extends survival, improves motor performance and decreases neuroinflammation in mouse model of amyotrophic lateral sclerosis. Neurobiol Dis 31:395–405

    Article  PubMed  CAS  Google Scholar 

  50. West MJ, Slomianka L, Gundersen HJ (1991) Unbiased stereological estimation of the total number of neurons in the subdivisions of the rat hippocampus using the optical fractionator. Anat Rec 231:482–497

    Article  PubMed  CAS  Google Scholar 

  51. Ying Z, Babb TL, Comair YG, Bingaman W, Bushey M, Touhalisky K (1998) Induced expression of NMDAR2 proteins and differential expression of NMDAR1 splice variants in dysplastic neurons of human epileptic neocortex. J Neuropathol Exp Neurol 57:47–62

    Article  PubMed  CAS  Google Scholar 

  52. Ying Z, Babb TL, Mikuni N, Najm I, Drazba J, Bingaman W (1999) Selective coexpression of NMDAR2A/B and NMDAR1 subunit proteins in dysplastic neurons of human epileptic cortex. Exp Neurol 159:409–418

    Article  PubMed  CAS  Google Scholar 

  53. Ying Z, Bingaman W, Najm IM (2004) Increased numbers of coassembled PSD-95 to NMDA-receptor subunits NR2B and NR1 in human epileptic cortical dysplasia. Epilepsia 45:314–321

    Article  PubMed  CAS  Google Scholar 

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Acknowledgments

We thank Professors Giuliano Avanzini and Alessandro Vercelli for critically reading the manuscript, Dr. Rita Garbelli for help with morphological analyses, and Don Ward for help with the English. We also thank Dr. Marina Boido for help with the stereological counts and Dr. Pietro Veglianese for the blind deconvolution analysis of VGLUT1 immunofluorescence. This study was supported in part by the Italian Ministry of Health, and the Region of Lombardy ‘Sovvenzione Globale Ingenio’ with help from the European Social Fund (Grant No. A0000844) to AF. All authors declare they have no conflicts of interest.

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Author notes

  1. Carlo Efisio Marras

    Present address: Epilepsy Neurosurgery and Oncology Unit, Ospedale Pediatrico Bambino Gesù, Piazza Sant’Onofrio 4, 00165, Rome, Italy

Authors and Affiliations

  1. Experimental Neurophysiology and Epileptology Department, Molecular Neuroanatomy and Pathogenesis Unit, Neurological Institute “C. Besta”, Via Temolo 4, 20126, Milan, Italy

    Adele Finardi, Francesca Colciaghi, Denise Locatelli, Paola Nobili & Giorgio Stefano Battaglia

  2. Epilepsy Surgery Center “Claudio Munari”, Niguarda General Hospital, Piazza Ospedale Maggiore 3, 20126, Milan, Italy

    Laura Castana & Giorgio LoRusso

  3. Neurosurgery Department, Neurological Institute “C. Besta”, Via Celoria 11, 20133, Milan, Italy

    Carlo Efisio Marras

  4. Molecular Biology Lab, Istituto di Ricerche Farmacologiche “Mario Negri”, Via La Masa 19, 20156, Milan, Italy

    Maddalena Fratelli

  5. Pathology Department, Niguarda General Hospital, Piazza Ospedale Maggiore 3, 20126, Milan, Italy

    Manuela Adele Bramerio

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Electronic supplementary material

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Supplementary material 1 (DOC 59 kb)

Supplementary material 2 (DOC 50 kb)

401_2013_1143_MOESM3_ESM.tif

Supplementary Fig. 1_Online Resource 3. Histograms illustrating the size frequency distribution of layer III and V pyramidal neurons from adjacent cortical areas of the eight FCD patients (a, b) and from cortical areas of non-epileptic/non-dysplastic control (c). Note that soma size is always less than 700 μm2 (TIFF 6928 kb)

401_2013_1143_MOESM4_ESM.tif

Supplementary Fig. 2_Online Resource 4. Cumulative fraction plots of soma size in type IIB FCD patients. (a) Dysmorphic neurons in epileptogenic/dysplastic areas have significantly larger somata than pyramidal neurons in adjacent areas. (b) Dysmorphic neurons in FCD patients with longer epilepsy have significantly larger somata than those in patients with shorter epilepsy. Kolmogorov–Smirnov test: maximum differences for cumulative fraction D are 0.77 (***p < 0.001) in a; and 0.33 (***p < 0.001) in b (TIFF 5636 kb)

401_2013_1143_MOESM5_ESM.tif

Supplementary Fig. 3_Online Resource 5. VGLUT1 immunostaining in FCD patients. a, c, d Representative low (a) and high (c, d) power microphotographs from patient 8. b Thionine-stained section adjacent to that shown in (a). Note that dysplastic regions with large dysmorphic neurons (upper left a, b) are intensely positive for VGLUT1. The boundary of VGLUT1 expression is not sharply defined but reduces progressively from dysplastic (a, b, upper left) to adjacent non-dysplastic areas (a, b, upper right). At higher magnification, VGLUT+ puncta are coarser and more intense around dysmorphic neurons (c) than those around pyramidal neurons of non-dysplastic cortex (d). The locations of the dysmorphic neurons in c and pyramidal neurons in d are indicated in a by an arrowhead and asterisk, respectively. V: blood vessels; wm: white matter. Scale bars: 1 mm in a, b; 25 μm in c, d (TIFF 26204 kb)

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Finardi, A., Colciaghi, F., Castana, L. et al. Long-duration epilepsy affects cell morphology and glutamatergic synapses in type IIB focal cortical dysplasia. Acta Neuropathol 126, 219–235 (2013). https://doi.org/10.1007/s00401-013-1143-4

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