Alterations in expression of glutamatergic transporters and receptors in sporadic Alzheimer's disease.

Excitatory neurotransmitter dysfunction has been discussed to be involved in the pathophysiology of Alzheimer's disease (AD). In the current study we investigated gene and protein expression patterns of glutamatergic receptors and transporters in brains of AD patients in various stages of disease using gene chip arrays, real time PCR and immunohistochemistry. We found marked impairment in the expression of excitatory amino acid transporters (EAAT1 and EAAT 2) at both gene and protein levels in hippocampus and gyrus frontalis medialis of AD patients, already in early clinical stages of disease. The loss of EAAT immunoreactivity was particularly obvious in the vicinity of amyloid plaques. In contrast, EAAT expression was up-regulated in the cerebellum of these patients. Furthermore, a significant up-regulation of the glutamatergic kainate (GRIK4) receptor observed by gene arrays was confirmed by quantitative RT-PCR in late stages in the hippocampus of AD patients. Moreover, there were down-regulations of other glutamatergic receptors such as NMDA (GRINL1A) and AMPA (GRIA4) receptors. Our data show marked changes in the functional elements of the glutamatergic synapses such as glutamatergic receptors and transporters and indicate impaired glutamate clearing rendering neurons susceptible to excess extracellular glutamate and support further the involvement of excitotoxic mechanisms in the pathogenesis of AD.

[1]  Kate A. Stafford,et al.  Efficient reversal of Alzheimer's disease fibril formation and elimination of neurotoxicity by a small molecule. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[2]  E. Mackenzie,et al.  NMDA Receptor Activation Inhibits α-Secretase and Promotes Neuronal Amyloid-β Production , 2005, The Journal of Neuroscience.

[3]  P. Riederer,et al.  From benefit to damage. Glutamate and advanced glycation end products in Alzheimer brain , 2006, Journal of Neural Transmission.

[4]  G. Cavaletti,et al.  Glutamate transporters in platelets: EAAT1 decrease in aging and in Alzheimer’s disease , 2004, Neurobiology of Aging.

[5]  Richard Weindruch,et al.  Gene-expression profile of the ageing brain in mice , 2000, Nature Genetics.

[6]  Dilip Rajagopalan,et al.  A comparison of statistical methods for analysis of high density oligonucleotide array data , 2003, Bioinform..

[7]  László G Puskás,et al.  RNA amplification results in reproducible microarray data with slight ratio bias. , 2002, BioTechniques.

[8]  Expression in brain of amyloid precursor protein mutated in the alpha‐secretase site causes disturbed behavior, neuronal degeneration and premature death in transgenic mice. , 1996 .

[9]  L. Ugozzoli,et al.  Fluorescent multicolor multiplex homogeneous assay for the simultaneous analysis of the two most common hemochromatosis mutations. , 2002, Analytical biochemistry.

[10]  J. Rinne,et al.  Alzheimer's disease: neuropathological correlates of cognitive and motor disorders , 1987, Acta neurologica Scandinavica.

[11]  J. Li,et al.  Free radicals in Parkinson's disease , 2002, Journal of Neurology.

[12]  Jo Vandesompele,et al.  Quantification of splice variants using real-time PCR , 2001, Nucleic Acids Res..

[13]  N. Bazan,et al.  Cyclooxygenase 2 RNA message abundance, stability, and hypervariability in sporadic alzheimer neocortex , 1997, Journal of neuroscience research.

[14]  Frank Speleman,et al.  Elimination of primer-dimer artifacts and genomic coamplification using a two-step SYBR green I real-time RT-PCR. , 2002, Analytical biochemistry.

[15]  H. Braak,et al.  Alzheimer's disease: amyloid plaques in the cerebellum , 1989, Journal of the Neurological Sciences.

[16]  D. Weinberger,et al.  Therapeutic Potential of Positive AMPA Receptor Modulators in the Treatment of Neuropsychiatric Disorders , 2006, CNS drugs.

[17]  J. Hugon,et al.  Glutamate toxicity enhances tau gene expression in neuronal cultures , 1997, Journal of neuroscience research.

[18]  Jiang Li,et al.  Differential gene expression patterns revealed by oligonucleotide versus long cDNA arrays. , 2002, Toxicological sciences : an official journal of the Society of Toxicology.

[19]  G. A. Whitmore,et al.  Importance of replication in microarray gene expression studies: statistical methods and evidence from repetitive cDNA hybridizations. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[20]  A. Floden,et al.  β-Amyloid-Stimulated Microglia Induce Neuron Death via Synergistic Stimulation of Tumor Necrosis Factor α and NMDA Receptors , 2005, The Journal of Neuroscience.

[21]  H. Braak,et al.  Pattern of brain destruction in Parkinson's and Alzheimer's diseases , 2005, Journal of Neural Transmission.

[22]  S. Mandel,et al.  Gene expression profiling of parkinsonian substantia nigra pars compacta; alterations in ubiquitin-proteasome, heat shock protein, iron and oxidative stress regulated proteins, cell adhesion/cellular matrix and vesicle trafficking genes , 2004, Journal of Neural Transmission.

[23]  H. Braak,et al.  Frequency of Stages of Alzheimer-Related Lesions in Different Age Categories , 1997, Neurobiology of Aging.

[24]  Mark A. Watson,et al.  EGR1 Target Genes in Prostate Carcinoma Cells Identified by Microarray Analysis* , 2000, The Journal of Biological Chemistry.

[25]  S. Lipton Paradigm shift in neuroprotection by NMDA receptor blockade: Memantine and beyond , 2006, Nature Reviews Drug Discovery.

[26]  M. Costanzi,et al.  NMDA receptor mediates tau-induced neurotoxicity by calpain and ERK/MAPK activation. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[27]  K. Jellinger,et al.  Age-related electrical status epilepticus during sleep and epileptic negative myoclonus in DRPLA , 2006, Neurology.

[28]  A. Makhro,et al.  Glutamate receptors modulate oxidative stress in neuronal cells. A mini-review , 2009, Neurotoxicity Research.

[29]  D. Rujescu,et al.  Oxidative stress related markers in the “VITA” and the centenarian projects , 2005, Neurobiology of Aging.

[30]  P. Dodd,et al.  Differential expression of N‐methyl‐d‐aspartate receptor NR2 isoforms in Alzheimer's disease , 2004, Journal of neurochemistry.

[31]  N. Bazan,et al.  Strong nuclear factor‐κB‐DNA binding parallels cyclooxygenase‐2 gene transcription in aging and in sporadic alzheimer's disease superior temporal lobe neocortex , 1998, Journal of neuroscience research.

[32]  Á. Simonyi,et al.  Kainic acid-mediated excitotoxicity as a model for neurodegeneration , 2007, Molecular Neurobiology.

[33]  S. P. Fodor,et al.  High density synthetic oligonucleotide arrays , 1999, Nature Genetics.

[34]  S. Scheff,et al.  Alzheimer's disease-related alterations in synaptic density: neocortex and hippocampus. , 2006, Journal of Alzheimer's disease : JAD.

[35]  Jacques Darcourt,et al.  Brain perfusion in Alzheimer's disease with and without apathy: a SPECT study with statistical parametric mapping analysis , 2002, Psychiatry Research: Neuroimaging.

[36]  F. Speleman,et al.  Accurate normalization of real-time quantitative RT-PCR data by geometric averaging of multiple internal control genes , 2002, Genome Biology.

[37]  J. Claverie Computational methods for the identification of differential and coordinated gene expression. , 1999, Human molecular genetics.

[38]  E. Masliah,et al.  Abnormal Glutamate Transport Function in Mutant Amyloid Precursor Protein Transgenic Mice , 2000, Experimental Neurology.

[39]  P. Riederer,et al.  Gene expression profile in streptozotocin rat model for sporadic Alzheimer’s disease , 2004, Journal of Neural Transmission.

[40]  W. Markesbery,et al.  Expression of microsomal epoxide hydrolase is elevated in Alzheimer's hippocampus and induced by exogenous β‐amyloid and trimethyl‐tin , 2006, The European journal of neuroscience.