heparitin-sulfate and Dementia

Molecular chaperons or amyloid-associated proteins (AAPs) are deposited in vascular and parenchymal amyloid lesions in Alzheimer's disease (AD) and other amyloidoses. AAPs, such as apolipoprotein E (ApoE) or apolipoprotein J (ApoJ) have been strongly implicated in the pathogenesis of AD in vitro and in vivo. Furthermore the possession of the ApoE in4 allele is a well-studied risk factor for AD. In view of the similarities between AD and both familial British dementia (FBD) and familial Danish dementia (FDD), we investigated the presence of AAPs in these two diseases to understand better their role in the general process of amyloidogenesis. Immunohistochemistry for ApoE, ApoJ, serum amyloid P (SAP), alpha-1-antichymotrypsin, cystatin C, heparan sulphate proteoglycans, such as agrin, perlecan, syndecans, glypican-1 and for heparan sulphate glycosaminoglycan (HS GAG) side chains was carried out together with immunohistochemical preparations specific to the amyloid subunits. Significant or extensive staining for ApoE, ApoJ, agrin, glypican-1 and HS GAG side chains was found in both amyloid (fibrillar) and preamyloid (nonfibrillar) deposits in FBD and FDD. The remaining AAPs, including SAP, were predominantly found in amyloid lesions. Only very weak staining was present in a small proportion of the amyloid lesions using perlecan immunohistochemistry. These findings suggest that the deposition patterns of AAPs in FBD and FDD are mostly similar to those in AD. The presence of AAPs in the preamyloid lesions supports the notion that chaperon molecules may play a role in the early steps of fibrillogenesis.

Topics: alpha 1-Antichymotrypsin; Alzheimer Disease; Amyloid; Amyloid Neuropathies; Apolipoproteins E; Dementia; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunohistochemistry; Membrane Glycoproteins; Molecular Chaperones; Nerve Tissue Proteins; Protein Conformation; Proteoglycans; Serum Amyloid P-Component; Syndecans

Microtubule-associated protein tau forms neurofibrillary lesions in Alzheimer's disease and several other neurodegenerative disorders, such as Niemann-Pick disease type C, subacute sclerosing panencephalitis, argyrophilic grain disease, myotonic dystrophy and motor neuron disease with neurofibrillary tangles. In this study we have compared the characteristics of tau pathology in these diseases using immunohistochemistry and phosphorylation-dependent and phosphorylation-independent anti-tau antibodies. The pattern of staining for heparan sulphate and alpha-synuclein was also investigated. We show that in all of these diseases tau deposits were stained by all anti-tau antibodies used, with the exception of argyrophilic grains which do not stain with antibody 12E8, confirming our previous findings. Heparan sulphate staining was present to a variable extent in all of these diseases, with the exception of subacute sclerosing panencephalitis, in which no staining was observed. Heparan sulphate staining coexisted with tau staining. In some cases it was more extensive than the tau staining. Alpha-synuclein staining was present in presynaptic terminals with the exception of one case of Alzheimer's disease, in which alpha-synuclein-positive Lewy bodies were observed in the hippocampal formation. These findings indicate that tau deposits are antigenically similar in several neurodegenerative diseases and that tau staining is often associated with heparan sulphate staining, supporting the concept that heparan sulphate may be involved in the assembly of tau protein into filaments.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; alpha-Synuclein; Dementia; Female; Heparitin Sulfate; Humans; Immunohistochemistry; Male; Microtubule-Associated Proteins; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurofibrils; Synucleins; tau Proteins

Alterations of the cerebral microvasculature have been reported in aging and in neurodegenerative disorders such as Alzheimer's disease. However, the exact role of microvascular alterations in the pathogenesis of neurodegeneration remains unknown. In the present report, the cerebral cortex microvasculature was studied by immunohistochemistry using a monoclonal antibody against vascular heparan sulfate proteoglycan protein core in normal aging controls. Alzheimer's disease, Down syndrome, Guam amyotrophic lateral sclerosis/parkinsonian dementia complex, Pick's disease and dementia pugilistica. In all dementing illnesses, increased microvascular pathology was evident compared to normal controls. Decreased microvascular density and numerous atrophic vessels were the primary abnormalities observed in all dementing disorders. These microvascular abnormalities demonstrated regional and laminar selectivity, and were primarily found in layers III and V of frontal and temporal cortex. Quantitative analysis employing computer-assisted microscopy demonstrated that the decrease in microvascular density in Alzheimer's disease was statistically significant compared to age-matched controls. In addition, extracellular heparan sulfate proteoglycan deposits were observed which colocalized with thioflavine S-positive senile plaques in Alzheimer's disease, Down syndrome and selected Guam dementia cases. In some cases, heparan sulfate proteoglycan was seen in senile plaques that appeared to be diffuse or primitive plaques that stained weakly with thioflavine. Heparan sulfate proteoglycan-containing neurons were also observed in Alzheimer's disease, as well as in Down syndrome and Guam cases. Glial staining for heparan sulfate proteoglycan was never observed. Our data support previous observations that microvascular pathology is found in aging and in Alzheimer's disease. The changes in Alzheimer's disease exceed those found in normal aging controls. We also found microvascular pathology in all other dementing disorders studied. Our studies further demonstrated that the microvascular pathology displays regional and laminar patterns which parallel patterns of neuronal loss. Finally, we also found that heparan sulfate proteoglycan is present in senile plaques and neurons not only as previously reported in Alzheimer's disease, but also in Down syndrome and Guam cases. Heparan sulfate proteoglycan in senile plaques may be derived from either the degenerating microvasculature or fro

Topics: Aged; Aged, 80 and over; Alzheimer Disease; Amyloid; Blood Vessels; Cerebrovascular Circulation; Dementia; Down Syndrome; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Microcirculation; Middle Aged; Proteoglycans; Reference Values