Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2000-2004  (6)
Material
Years
Year
  • 1
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Cerebral inflammatory events play an important part in the pathogenesis of Alzheimer's disease (AD). Agonists of the peroxisome proliferator-activated receptor gamma (PPARγ), a nuclear hormone receptor that mediates anti-inflammatory actions of non-steroidal anti-inflammatory drugs (NSAIDs) and thiazolidinediones, have been therefore proposed as a potential treatment of AD. Experimental evidence suggests that cortical noradrenaline (NA) depletion due to degeneration of the locus ceruleus (LC) – a pathological hallmark of AD – plays a permissive role in the development of inflammation in AD. To study a possible relationship between NA depletion and PPARγ-mediated suppression of inflammation we investigated the influence of NA on PPARγ expression in murine primary cortical astrocytes and neurons. Incubation of astrocytes and neurons with 100 µm NA resulted in an increase of PPARγ mRNA as well as PPARγ protein levels in both cell types. These effects were blocked by the β-adrenergic antagonist propranolol but not by the α-adrenergic antagonist phentolamine, suggesting that they might be mediated by β-adrenergic receptors. Our results indicate for the first time that PPARγ expression can be modulated by the cAMP signalling pathway, and suggest that the anti-inflammatory effects of NA on brain cells may be partly mediated by increasing PPARγ levels. Conversely, decreased NA due to LC cell death in AD may reduce endogenous PPARγ expression and therefore potentiate neuroinflammatory processes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Journal of neurochemistry 78 (2001), S. 0 
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The expression of inducible nitric oxide synthase (NOS2) in glial cells is inhibited by neurotransmitters such as norepinephrine (NE) which elevate cAMP levels. We examined the molecular basis for this effect using a 2.2-kb fragment of the rat NOS2 promoter transfected into rat C6 glioma cells. Promoter activation (up to six-fold) by lipopolysaccharide (LPS) and interferon-γ (IFNγ) was reduced by NE, which alone had no effect. However, a promoter construct extending to bp −130 and containing the proximal nuclear factor-kappa B (NF-κB) binding site was minimally activated by LPS and cytokines, but activated up to three-fold by NE. Deletion analysis identified a 27-bp region (bp −187 to −160) as critical for mediating this suppressive effect. This region also enhanced promoter activation by LPS and cytokines, and prevented activation by NE alone. Gel shift analysis revealed constitutive binding to this region, and induction by NE of additional complexes which could be blocked by an antibody against CREB. NE also increased levels of the IκBα protein which could contribute to its suppressive effects. These results identify a critical role for this 27-bp region in regulation of NOS2 promoter activation and suppression by cAMP.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The stress response (SR) can block inflammatory gene expression by preventing activation of transcription factor nuclear factor-kappa B (NF-κB). As inflammatory gene expression contributes to the pathogenesis of demyelinating diseases, we tested the effects of the SR on the progression of the demyelinating disease experimental autoimmune encephalomyelitis (EAE). EAE was actively induced in C57BL/6 mice using an encephalitogenic myelin oligodendrocyte glycoprotein (MOG35−55) peptide. Whole body hyperthermia was used to induce a heat shock response (HSR) in immunized mice 2 days after the booster MOG35−55 peptide injection. The HSR reduced the incidence of EAE by 70%, delayed disease onset by 6 days, and attenuated disease severity. The HSR attenuated leukocyte infiltration into CNS assessed by quantitation of perivascular infiltrates, and by reduced staining for CD4 and CD25 immunopositive T-cells. T-cell activation, assessed by the production of interferon γ (IFNγ) in response to MOG35−55, was also decreased by the HSR. The HSR reduced inflammatory gene expression in the brain that normally occurs during EAE, including the early increase in RANTES (regulated on activation of normal T-cell expressed and secreted) expression, and the later expression of the inducible form of nitric oxide synthase. The early activation of transcription factor NF-κB was also blocked by the HSR. The finding that the SR reduces inflammation in the brain and the clinical severity of EAE opens a novel therapeutic approach for prevention of autoimmune diseases.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford UK : Blackwell Science Ltd.
    Journal of neurochemistry 75 (2000), S. 0 
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: The targeting of mRNAs to specific subcellular locations is believed to facilitate the rapid and selective incorporation of their protein products into complexes that may include membrane organelles. In oligodendrocytes, mRNAs that encode myelin basic protein (MBP) and select myelin-associated oligodendrocytic basic proteins (MOBPs) locate in myelin sheath assembly sites (MSAS). To identify additional mRNAs located in MSAS, we used a combination of subcellular fractionation and suppression subtractive hybridization. More than 50% of the 1,080 cDNAs that were analyzed were derived from MBP or MOBP mRNAs, confirming that the method selected mRNAs enriched in MSAS. Of 90 other cDNAs identified, most represent one or more mRNAs enriched in rat brain myelin. Five cDNAs, which encode known proteins, were characterized for mRNA size(s), enrichment in myelin, and tissue and developmental expression patterns. Two of these, peptidylarginine deiminase and ferritin heavy chain, have recognized roles in myelination. The corresponding mRNAs were of different sizes than the previously identified mRNA, and they had tissue and development expression patterns that were indistinguishable from those of MBP mRNA. Three other cDNAs recognize mRNAs whose proteins (SH3p13, KIF1A, and dynein light intermediate chain) are involved in membrane biogenesis. Although enriched in myelin, the tissue and developmental distribution patterns of these mRNAs differed from those of MBP mRNA. Six other cDNAs, which did not share significant sequence homology to known mRNAs, were also examined. The corresponding mRNAs were highly enriched in myelin, and four had tissue and developmental distribution patterns indistinguishable from those of MBP mRNA. These studies demonstrate that MSAS contain a diverse population of mRNAs, whose locally synthesized proteins are placed to contribute to myelin sheath assembly and maintenance. Characterization of these mRNAs and proteins will help provide a comprehensive picture of myelin sheath assembly.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The inflammatory responses in many cell types are reduced by noradrenaline (NA) binding to β-adrenergic receptors. We previously demonstrated that cortical inflammatory responses to aggregated amyloid beta (Aβ) are increased if NA levels were first depleted by lesioning locus ceruleus (LC) noradrenergic neurons, which replicates the loss of LC occurring in Alzheimer's disease. To examine the molecular basis for increased responses, we used the selective neurotoxin DSP4 to lesion the LC, and then examined levels of putative anti-inflammatory molecules. Inflammatory responses were achieved by injection of aggregated Aβ1–42 peptide and IL-1β into frontal cortex, which induced neuronal inducible nitric oxide synthase (iNOS) and microglial IL-1β expression. DSP4-treatment reduced basal levels of nuclear factor kappa B (NF-κB) inhibitory IκB proteins, and of heat shock protein (HSP)70. Inflammatory responses were prevented by co-injection (ibuprofen or ciglitzaone) or oral administration (pioglitazone) of peroxisome proliferator-activated receptor gamma (PPARγ) agonists. Treatment with PPARγ agonists restored IκBα, IκBβ, and HSP70 levels to values equal or above those observed in control animals, and reduced activation of cortical NF-κB. These results suggest that noradrenergic depletion reduces levels of anti-inflammatory molecules which normally limit cortical responses to Aβ, and that PPARγ agonists can reverse that effect. These findings suggest one mechanism by which PPARγ agonists could provide benefit in neurological diseases having an inflammatory component.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Malignant astrocytomas are among the most common brain tumours and few therapeutic options exist. It has recently been recognized that the ligand-activated nuclear receptor PPARγ can regulate cellular proliferation and induce apoptosis in different malignant cells. We report the effect of three structurally different PPARγ agonists inducing apoptosis in human (U87MG and A172) and rat (C6) glioma cells. The PPARγ agonists ciglitazone, LY171 833 and prostaglandin-J2, but not the PPARα agonist WY14643, inhibited proliferation and induced cell death. PPARγ agonist-induced cell death was characterized by DNA fragmentation and nuclear condensation, as well as inhibited by the synthetic receptor-antagonist bisphenol A diglycidyl ether (BADGE). In contrast, primary murine astrocytes were not affected by PPARγ agonist treatment. The apoptotic death in the glioma cell lines treated with PPARγ agonists was correlated with the transient up-regulation of Bax and Bad protein levels. Furthermore, inhibition of Bax expression by specific antisense oligonucleotides protected glioma cells against PPARγ-mediated apoptosis, indicating an essential role of Bax in PPARγ-induced apoptosis. However, PPARγ agonists not only induced apoptosis but also caused redifferentiation as indicated by outgrowth of long processes and expression of the redifferentiation marker N-cadherin in response to PPARγ agonists. Taken together, treatment of glioma cells with PPARγ agonists may hold therapeutic potential for the treatment of gliomas.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...