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Biomedical subjects

J R Wands

Publications and source records attributed to J R Wands.

At least 37 records · Page 2Linked to original sources
PubMed2000

Overexpression of human aspartyl (asparaginyl) beta-hydroxylase is associated with malignant transformation.

The human aspartyl (asparaginyl) beta-hydroxylase (HAAH) is a highly conserved enzyme that hydroxylates epidermal growth factor-like domains in transformation-associated proteins. We previously reported overexpression of the HAAH gene in human hepatocellular carcinomas and cholangiocarcinomas (L. Lavaissiere et al., J. Clin. Investig., 98: 1313-1323, 1996). In the present study, we determined whether HAAH protein overexpression was linked to cellular proliferation or malignant transformation of bile ducts by using a human disease and rat model of bile duct proliferation. In addition, the transforming properties of the AAH genes were assessed by transient and stable transfection of NIH-3T3 cells with human and murine wild-type as well as mutant cDNA constructs that lacked hydroxylation activity. Cellular characteristics of the malignant phenotype were assessed by formation of transformed foci, growth in soft agar, and tumor development in nude mice. We found that HAAH gene expression was undetectable during bile duct proliferation in both human disease and rat models as compared with cholangiocarcinoma. Overexpression of HAAH in NIH-3T3 cells was associated with generation of a malignant phenotype, and enzymatic activity was required for cellular transformation. These findings suggest that overexpression of HAAH is linked to cellular transformation of biliary epithelial cells.

3T3 Cells↗
PubMed2000

Grb7 signal transduction protein mediates metastatic progression of esophageal carcinoma.

We have previously reported the association of tumor cell invasion with expression of growth factor receptor-bound protein 7 (Grb7). This molecule contains a Src homology 2 (SH2) domain and shares structural homology with a cell migration molecule designated Mig-10 found in Caenorhabditis elegans. In the present study, Grb7 expression was analyzed in human esophageal carcinomas with or without metastatic spread. The Grb7 protein was overexpressed in 14 of 31 esophageal carcinomas as compared to the adjacent normal mucosa (45%) and this finding was significantly correlated with the presence of lymph node metastases. We also identified that Grb7 protein in esophageal carcinoma cells was phosphorylated on tyrosine by epidermal growth factor as well as attachment to extracellular matrix proteins including fibronectin. Such fibronectin-dependent phosphorylation of Grb7 was regulated by integrin signaling that leads to the interaction with focal adhesion kinase protein. Furthermore, ectopic expression of a Grb7-SH2 dominant-negative fragment inhibited the fibronectin-dependent phosphorylation of endogenous Grb7, and reduced migration of esophageal carcinoma cells into fibronectin. Our results suggest a role of Grb7 mediated signal transduction in generation of an invasive cell phenotype against extracellular matrix, and thus contributes to metastatic progression of human esophageal carcinoma.

Adenocarcinoma↗
PubMed2000

Gene therapy of hepatocellular carcinoma in vitro and in vivo in nude mice by adenoviral transfer of the Escherichia coli purine nucleoside phosphorylase gene.

Expression of viral or bacterial enzymes in tumor cells to convert nontoxic prodrugs into highly toxic metabolites is an attractive gene-therapeutic approach for the treatment of hepatocellular carcinoma (HCC). The Escherichia coli purine nucleoside phosphorylase (PNP) converts purine analogs into freely diffusible metabolites, which are highly toxic to dividing and nondividing cells. We investigated the antitumor effects of PNP in the human HCC cell lines, HepG2, Hep3B, and HuH-7, and performed a comparison with herpes simplex thymidine kinase (TK). The genes for PNP, TK, and enhanced green fluorescent protein (EGFP) were delivered to HCC cells by identical adenoviral vectors. Fludarabine and ganciclovir (GCV) served as prodrugs for PNP and TK, respectively. Expression of PNP highly sensitized HCC cells to fludarabine treatment. Fludarabine concentrations between 0.5 and 1 microg/mL killed 100% of the cells expressing PNP with no detectable toxicity in control cells expressing EGFP. Expression of PNP in as few as 10% of HCC cells induced efficient killing of most bystander cells. Expression of TK followed by GCV treatment produced a potent growth inhibition but failed to kill all TK-expressing HCC cells. More importantly, the TK system exhibited a lower degree of bystander effect. Adenoviral delivery of PNP followed by fludarabine administration prevented subcutaneous and intrahepatic tumor formation in nude mice and was also effective for the treatment of established tumors. These results demonstrate the potential of the PNP/fludarabine system for the treatment of HCC.

Adenoviridae↗
PubMed2000

Oxidative stress and hypoxia-like injury cause Alzheimer-type molecular abnormalities in central nervous system neurons.

Neuronal loss and neuritic/cytoskeletal lesions (synaptic disconnection and proliferation of dystrophic neurites) represent major dementia-associated abnormalities in Alzheimer's disease (AD). This study examined the role of oxidative stress as a factor contributing to both the cell death and neuritic degeneration cascades in AD. Primary neuron cultures were treated with H2O2 (9-90 microM) or desferrioxamine (2-25 microM) for 24 h and then analyzed for viability, mitochondrial mass, mitochondrial function, and pro-apoptosis and sprouting gene expression. H2O2 treatment causes free-radical injury and desferrioxamine causes hypoxia-type injury without free radical generation. The H2O2-treated cells exhibited sustained viability but neurite retraction, impaired mitochondrial function, increased levels of the pro-apoptosis gene product CD95/Fas, reduced expression of N2J1-immunoreactive neuronal thread protein and synaptophysin, and reduced distribution of mitochondria in neuritic processes. Desferrioxamine treatment resulted in dose-dependent neuronal loss associated with impaired mitochondrial function, proliferation of neurites, and reduced expression of GAP-43, which has a role in path-finding during neurite outgrowth. The results suggest that oxidative stress can cause neurodegeneration associated with enhanced susceptibility to apoptosis due to activation of pro-apoptosis genes, neurite retraction (synaptic disconnection), and impaired transport of mitochondria to cell processes where they are likely required for synaptic function. In contrast, hypoxia-type injury causes neuronal loss with proliferation of neurites (sprouting), impaired mitochondrial function, and reduced expression of molecules required to form and maintain synaptic connections. Since similar abnormalities occur in AD, both oxidative stress and hypoxic injury can contribute to AD neurodegeneration.

Alzheimer Disease↗
PubMed2000

Cytotoxic T cell responses against hepatitis B virus polymerase induced by genetic immunization.

BACKGROUND/AIMS: Individuals with chronic hepatitis B may benefit from genetic (DNA-based) immunization through induction of viral clearance by enhancement of suboptimal cellular immune responses. While marked cellular immune responses to hepatitis B virus (HBV) nucleocapsid and envelope proteins occur after genetic immunization in mice, it is unknown whether genetic immunization is capable of eliciting such responses to HBV polymerase. We wished to develop assays for the determination of HBV polymerase specific immune responses in mice and investigate whether genetic immunization may elicit humoral and cellular immune responses to HBV polymerase. METHODS: BALB/c (H-2d) mice were injected with a DNA expression construct for HBV polymerase. Humoral immune responses to HBV polymerase were analyzed with a newly established ELISA. Cellular immune responses were determined using recombinant vaccinia virus infected target cells expressing HBV polymerase at high levels. RESULTS: Assays for the detection of HBV polymerase-specific immune responses were developed. Immunized animals exhibited substantial polymerase-specific cytotoxic T lymphocyte responses. However, no humoral immune responses to HBV polymerase were detectable. CONCLUSIONS: Our study demonstrates that DNA-based immunization will generate substantial CTL responses to HBV polymerase and may be an important component of an immunotherapeutic strategy to combat chronic HBV infection.

3T3 Cells↗
PubMed2000

Mitochondrial DNA damage as a mechanism of cell loss in Alzheimer's disease.

Aging is associated with impaired mitochondrial function caused by accumulation of oxygen free radical-induced mitochondrial (Mt) DNA mutations. One prevailing theory is that age-associated diseases, including Alzheimer's disease (AD), may be precipitated, propagated, or caused by impaired mitochondrial function. To investigate the role of MtDNA relative to genomic (Gn) DNA damage in AD, temporal lobe samples from postmortem AD (n = 37) and control (n = 25) brains were analyzed for MtDNA and GnDNA fragmentation, mitochondrial protein and cytochrome oxidase expression, MitoTracker Green fluorescence (to assess mitochondrial mass/abundance), and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OHdG) immunoreactivity. Brains with AD had more extensive nicking and fragmentation of both MtDNA and GnDNA as demonstrated by agarose gel electrophoresis, end-labeling, and the in situ terminal deoxynucleotide transferase end-labeling (TUNEL) assay, and only the brains with AD had detectable 8-OHdG immunoreactivity in cortical neurons. Increased MtDNA damage in AD was associated with reduced MtDNA content, as demonstrated by semiquantitative PCR analysis and reduced levels of Mt protein and cytochrome oxidase expression by Western blot analysis or immunohistochemical staining with image analysis. The finding of reduced MitoTracker Green fluorescence in AD brains provided additional evidence that reduced Mt mass/abundance occurs with AD neurodegeneration. The presence of increased MtDNA and GnDNA damage in AD suggest dual cell death cascades in AD. Impaired mitochondrial function caused by MtDNA damage may render brain cells in AD more susceptible to oxidative injury and thereby provide a mechanism by which systemic or environmental factors could influence the course of disease.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2000

Rabbit cytochrome P450 4B1: A novel prodrug activating gene for pharmacogene therapy of hepatocellular carcinoma.

Gene therapy using vector-mediated transfer of prodrug activating genes is a promising treatment approach for malignant tumors. As demonstrated recently, the novel prodrug activating gene coding for rabbit cytochrome P450 4B1 (CYP4B1) is able to induce tumor cell death at low micromolar concentrations in glioblastoma cells after treatment with the prodrug 4-ipomeanol (4-IM) in vitro and in vivo. The rabbit CYP4B1 converts this prodrug and other furane analogs and aromatic amines, such as 2-aminoanthracene, to highly toxic alkylating metabolites, whereas the human isoenzyme exhibits only minimal enzymatic activity. In the present study, the cDNA encoding rabbit CYP4B1 was used for pharmacogene therapy of hepatocellular carcinoma (HCC). Cell clones derived from the human HCC cell lines Hep3B, HuH-7, and HepG2 and stably expressing the chimeric protein CYP4B1-EGFP (the CYP4B1 coding sequence fused to the enhanced green fluorescent protein (EGFP) gene) were selected. HCC clones expressing EGFP served as controls. 4-IM rapidly induced tumor cell death in CYP4B1-EGFP-expressing clones at low concentrations (a 50% lethal dose of between 0.5 and 2 microg/mL). No signs of toxicity were found in control cells expressing EGFP even at high prodrug concentrations (20 microg/mL). Cell death occurred by apoptosis and was independent of functional p53. A pronounced direct bystander effect was observed in Hep3B cells, whereas bystander HepG2 and HuH-7 cells were highly resistant to toxic 4-IM metabolites. These results demonstrate that the CYP4B1/4-1M system efficiently and rapidly induces cell death in HCC cells, and that a cell line-specific mechanism may exist that limits the extent of the bystander effect of this novel prodrug activating system.

Animals↗
PubMed2000

Expression and antitumor effects of TRAIL in human cholangiocarcinoma.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)/Apo2L has been recently identified as important in promoting programmed cell death in breast and colon adenocarcinomas. In this study, we investigated the expression and therapeutic potential of TRAIL in cholangiocarcinoma, one of the most devastating human hepatic malignancies. Expression of TRAIL receptors was determined in 13 patients with resectable intrahepatic cholangiocarcinoma. Cellular effects of TRAIL in promoting apoptosis of human cholangiocarcinoma cells were analyzed after exposure to recombinant protein, as well as following transfection with a cDNA expression construct. In vivo effects of TRAIL on tumor growth were investigated after subcutaneous injection of cholangiocarcinoma cells into nude mice. Analysis of 13 clinical and tissue samples revealed that TRAIL receptors containing the death domain were present in all cholangiocarcinomas as well as paired normal hepatic tissues derived from surgically resected margins. In contrast, 7 tumors did not express the TRAIL decoy receptors lacking the death domain; such receptors were detectable in all of the normal hepatic tissue counterparts. Recombinant TRAIL induced extensive programmed cell death in cholangiocarcinoma cell lines lacking decoy receptor expression. Transfection of the ectodomain of TRAIL also induced cellular apoptosis; this effect was abolished by introduction of the generalized lymphoproliferative disease-like mutation in the TRAIL protein. Finally, in vivo administration of recombinant TRAIL substantially inhibited subcutaneous tumor growth of human cholangiocarcinoma cells. Induction of apoptosis in tumor cells is possible with a biologically active TRAIL, and suggests that this cytokine is a promising antitumor agent against human cholangiocarcinoma.

Amino Acid Sequence↗
PubMed2000

Role of aberrant nitric oxide synthase-3 expression in cerebrovascular degeneration and vascular-mediated injury in Alzheimer's disease.

Nitric oxide (NO) is an important signaling molecule that is generated through the catalytic activity of nitric oxide synthase (NOS). In the brain, NO mediates neuronal survival, synaptic plasticity, vascular smooth muscle relaxation, and endothelial cell permeability. Previous studies demonstrated aberrant expression of the NOS-III gene in neurons and glial cells in brains with Alzheimer's disease (AD). Since NOS-III is also expressed in vascular cells, and cerebrovascular disease (CVD) frequently complicates the pathology of AD, we investigated the role of NOS-III in relation to CVD in AD. Vasculopathy in AD + CVD was characterized by thickening and hyalinization of the media of small and medium-size vessels, variable degrees of beta-amyloid (A beta) deposition, and increased apoptosis of vascular smooth muscle and endothelial cells, particularly involving white matter vessels. These abnormalities were correlated with reduced levels of NOS-III expression in cerebral vessels. Double-labeling studies demonstrated that the low levels of cerebrovascular NOS-III were associated with increased levels of the pro-apoptosis gene product, p53 in smooth muscle and endothelial cells, suggesting a role for altered NOS-III expression in AD-associated vascular degeneration. Constitutively reduced cerebrovascular NOS-III expression and NO production could also lead to cerebral hypoperfusion due to impaired vasodilation responses, and diminished capacity to remove respiratory waste products and toxins from the extracellular space due to reduced capillary permeability. The role for phosphodiesterases as modulators of NOS activity is discussed, as these molecules represent potential therapeutic targets given their cell type and cyclic nucleotide specificities of action.

Alzheimer Disease↗
PubMed2000

Oxygen free radical injury is sufficient to cause some Alzheimer-type molecular abnormalities in human CNS neuronal cells.

Cell loss and neuritic/cytoskeletal lesions represent two of the major categories of dementia-associated structural abnormalities in Alzheimer's disease (AD). Cell loss is ultimately mediated by apoptosis and mitochondrial DNA damage due to enhanced sensitivity to oxidative stress, but the mechanism responsible for the neuritic/cytoskeletal lesions including the abnormal proliferation of cortical neurites is not known. This study examines the potential role of oxygen free radical injury as a factor contributing to both cell death and neuritic sprouting cascades in AD. PNET2 human neuronal cells were treated with H2O2 (8 micro M to 88 micro M) for 24 hours and then analyzed for viability, DNA damage, and pro-apoptosis, survival, and sprouting gene expression and signaling. H2O2-treatment resulted in dose-dependent increases in cell death due to genomic and mitochondrial DNA damage associated with increased levels of 8-OHdG and the p53 and CD95 pro-apoptosis genes, reduced levels of the Bcl-2 survival gene, activation of JNK and p38 stress kinases, and inhibition of PI3 kinase survival signaling. However, the H2O2-treated cells also manifested increased expression of growth and sprouting molecules, including GAP-43, nitric oxide synthase 3, neuronal thread protein (NTP; approximately 17 kD and approximately 21 kD forms), proliferating cell nuclear antigen, and phospho-Erk MAPK, and normal levels of the AD-associated approximately 41 kD NTP species, cyclin dependent kinase 5 (cdk-5), and phospho-tau. In addition, the H2O2-treated cells had increased levels of p25, the catalytically active and stable cleavage product of p35, which regulates cdk-5 activity. Previous studies demonstrated p25 accumulation in AD brains and p25-induced hyperphosphorylation of tau and neuronal apoptosis. The findings herein suggest that oxygen free radical injury in human CNS neuronal cells is sufficient to cause some but not all of the pro-death and pro-sprouting molecular abnormalities that occur in AD.

Journal Article↗
PubMed2000

Partial rescue of ethanol-induced neuronal apoptosis by growth factor activation of phosphoinositol-3-kinase.

BACKGROUND: Ethanol inhibition of insulin signaling pathways may contribute to impaired central nervous system (CNS) development in the fetal alcohol syndrome and brain atrophy associated with alcoholic neurodegeneration. Previous studies demonstrated ethanol inhibition of insulin-stimulated growth in PNET2 CNS-derived proliferative (immature) neuronal cells. We now provide evidence that the growth-inhibitory effect of ethanol in insulin-stimulated PNET2 cells is partly due to apoptosis. METHODS: Control and ethanol-treated PNET2 cells were stimulated with insulin and analyzed for viability, apoptosis, activation of pro-apoptosis and survival gene expression and signaling pathways, and evidence of caspase activation. RESULTS: Ethanol-treated PNET2 neuronal cells exhibited increased apoptosis mediated by increased levels of p53 and phospho-amino-terminal c-jun kinase (phospho-JNK), and reduced levels of Bcl-2, phosphoinositol 3-kinase (PI3 K), and intact (approximately 116 kD) poly (ADP ribose) polymerase (PARP), a deoxyribonucleic acid repair enzyme and important substrate for caspase 3. Partial rescue from ethanol-induced neuronal cell death was effected by culturing the cells in medium that contained 2% fetal calf serum instead of insulin, or insulin plus either insulin-like growth factor type 1 or nerve growth factor. The resulting enhanced viability was associated with reduced levels of p53 and phospho-JNK and increased levels of PI3 K and intact PARP. CONCLUSIONS: The findings suggest that ethanol-induced apoptosis of insulin-stimulated neuronal cells can be reduced by activating PI3 K and inhibiting pro-apoptosis gene expression and intracellular signaling through non-insulin-dependent pathways.

Apoptosis↗
PubMed2000

Ethanol inhibition: the humoral and cellular immune response to hepatitis C virus NS5 protein after genetic immunization.

BACKGROUND: The combination of chronic hepatitis C virus (HCV) and ethanol may increase viral replication, impair cellular immunity, and result in severe and progressive liver disease. Because HCV nonstructural proteins play a major role in viral elimination, we examined the cellular and humoral immune responses after genetic immunization against NS5 in a chronic ethanol mouse model. METHODS: Mice were fed an ethanol or isocaloric pair-fed control liquid diet and were immunized with HCV NS5-expression plasmid. RESULTS: The humoral and cellular arms of the immune system were significantly impaired in ethanol-fed mice. Abstinence partially reversed the inhibitory effects on antibody levels and the CD4+ proliferative immune response but did not restore the CD8+ cytotoxic T-cell response to this HCV nonstructural protein. Furthermore, we determined whether murine interleukin-2 coadministration with the NS5 expression plasmid would reverse the inhibitory effects of chronic ethanol consumption; again, partial restoration was observed for B-cell and CD4+ T-cell activity, but not for cytotoxic T cells. CONCLUSIONS: These results suggest that the high rate of chronic HCV infection in alcoholics may be due to ethanol's effects on antiviral immune responses.

Animals↗
PubMed1999

Characterization and binding of intracellular antibody fragments to the hepatitis C virus core protein.

The monoclonal antibody C7-50 binds to the HCV core protein with high sensitivity and specificity. The coding sequences of the variable domains of the antibody were determined following cDNA cloning of the Fab and sFv fragments. Subsequently, intracellular expression and binding of these antibody fragments to the HCV core protein as a potential antiviral approach were studied. There was high specificity and sensitivity of binding of bacterially expressed, recombinant C7-50 Fab to HCV core as measured by EIA and immunoblot. For expression in mammalian cells, the C7-50 antibody was subcloned in the sFv format by the introduction of a (Gly(4)Ser)(3) linker spaced between light and heavy chains. Northern and Western blot analysis as well as confocal microscopy established the targeted expression of the C7-50 sFv antibody fragment in the endoplasmic reticulum of transfected cells. The colocalization and intracellular binding of the antibody fragment to HCV core protein was confirmed by immunoprecipitation and subsequent immunoblot analysis. This study demonstrates that gene delivery of cDNA coding sequences inducing intracellular expression of C7-50 antibody fragments leads to binding of the antibody fragment to the HCV core protein within the secretory compartment of transfected cells. Intracellular immunization represents a promising antiviral approach to interfere with the life cycle of HCV.

Amino Acid Sequence↗
PubMed1999

Identification and expression of glycine decarboxylase (p120) as a duck hepatitis B virus pre-S envelope-binding protein.

A 120-kilodalton protein (p120) was identified in the duck liver that binds to several truncated versions of duck hepatitis B virus (DHBV) pre-S envelope protein, suggesting p120 may serve as a DHBV co-receptor. The amino acid sequences of tryptic peptides from purified p120 were found to be the duck p protein of the glycine decarboxylase complex (DGD). DGD cDNA cloning revealed extensive protein conservation with the chicken homologue except for several insertions in the N-terminal leader sequence. The DGD cDNA contained no in-frame AUG codon at the predicted initiation site of the open reading frame, and site-directed mutagenesis experiments established an AUU codon as the translational initiator. The DGD protein expressed in rabbit reticulocyte lysates bound truncated DHBV pre-S protein identical to that of p120 derived from duck liver confirming DGD as p120. Moreover, transfection studies in liver- and kidney-derived cells revealed both cell surface and cytoplasmic expression of the protein. Cloning of the glycine decarboxylase cDNA will permit a direct test of whether it functions as a cell surface co-receptor or as a co-factor in the DHBV replication cycles.

Amino Acid Oxidoreductases↗
PubMed1999

Intracellular expression of a cloned antibody fragment interferes with hepatitis B virus surface antigen secretion.

We evaluated the potential of an intracellularly expressed antibody fragment to interfere with hepatitis B virus (HBV). Sequences coding for the immunoglobulin variable regions of the HBV surface antigen (HBsAg) specific monoclonal antibody 5C3 were isolated and characterized. A secretory pathway-targeted, 5C3 derived single chain Fv (sFv) fragment was expressed in HuH-7 hepatocellular carcinoma cells together with HBsAg. Quantification of extracellular HBsAg levels in the cell culture supernatant demonstrated that the presence of the 5C3 sFv equipped with a secretory pathway retention signal SEKDEL reduced extracellular HBsAg levels by a mean of 85%. Co-immunoprecipitation studies revealed that the 5C3 sFv targeted to the secretory pathway physically interacted with its target antigen, HBsAg. Confocal microscopy studies confirmed the intracellular expression and colocalization of the 5C3 sFv and HBsAg. We conclude that certain intracellularly expressed antibody fragments will substantially interfere with HBV antigen secretion from the cell.

Amino Acid Sequence↗
PubMed1999

A short region in the genome of hepatitis B virus is critical for maintenance of high transcript levels.

The majority of hepatitis B virus (HBV) transcripts are not normally spliced during the viral life cycle, but several splice donor and acceptor sites are conserved on HBV transcripts. In particular, the genome region between nt 450 and 500 of the HBV genome appears to be rich in such sequences. In this study we deleted a short 30-nt sequence between a conserved splice donor site at HBV genome position 462 and a splice acceptor site at position 491, thus deleting the surface/polymerase open reading frames by 10 amino acid residues. At the transcriptional level, this deletion led to >99% reduction of the 2.1-kb class of subgenomic transcripts in transfected cells. Nuclear run-on experiments revealed that the transcription rate of the deleted 2.1-kb transcript is unchanged when compared with the wildtype, suggesting a posttranscriptional mechanism for the downregulation of the deleted transcript. In addition, experiments with a replication-competent HBV mutant containing the 30-nt deletion showed that the corresponding 10-amino-acid sequence within the reverse transcriptase domain of the polymerase protein appeared to be nonessential.

Amino Acid Sequence↗
PubMed1999

Neuritic sprouting with aberrant expression of the nitric oxide synthase III gene in neurodegenerative diseases.

Neuronal loss, synaptic disconnection and neuritic sprouting correlate with dementia in Alzheimer's disease (AD). Nitric oxide (NO) is an important synaptic plasticity molecule generated by nitric oxide synthase (NOS) oxidation of a guanidino nitrogen of L-arginine. Experimentally, the NOS III gene is modulated with neuritic sprouting. In a previous study, NOS III expression was found to be abnormal in cortical neurons, white matter glial cells, and dystrophic neurites in AD and Down syndrome brains. The present study demonstrates the same abnormalities in neuronal and glial NOS III expression with massive proliferation of NOS III-immunoreactive neurites and glial cell processes in other neurodegenerative diseases including: diffuse Lewy body disease, Pick's disease, progressive supranuclear palsy, amyotrophic lateral sclerosis, multiple system atrophy, and Parkinson's disease. However, each disease, including AD, was distinguished by the selective alterations in NOS III expression and sprouting in structures marred by neurodegeneration. Double label immunohistochemical staining studies demonstrated nitrotyrosine and NOS III co-localized in only rare neurons and neuritic sprouts, suggesting that peroxynitrite formation and nitration of growth cone proteins may not be important consequences of NOS III enzyme accumulation. The results suggest that aberrant NOS III expression and NOS III-associated neuritic sprouting in the CNS are major abnormalities common to several important neurodegenerative diseases.

Aged↗