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- Hollerhage, M., et al.
(författare)
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Piericidin A Aggravates Tau Pathology in P301S Transgenic Mice
- 2014
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 9:12
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The P301S mutation in exon 10 of the tau gene causes a hereditary tauopathy. While mitochondrial complex I inhibition has been linked to sporadic tauopathies. Piericidin A is a prototypical member of the group of the piericidins, a class of biologically active natural complex I inhibitors, isolated from streptomyces spp. with global distribution in marine and agricultural habitats. The aim of this study was to determine whether there is a pathogenic interaction of the environmental toxin piericidin A and the P301S mutation. Methods: Transgenic mice expressing human tau with the P301S-mutation (P301S(+/+)) and wild-type mice at 12 weeks of age were treated subcutaneously with vehicle (N=10 P301S(+/+), N = 7 wild-type) or piericidin A (N = 9 P301S(+/+), N = 9 wild-type mice) at a dose of 0.5 mg/kg/d for a period of 28 days via osmotic minipumps. Tau pathology was measured by stereological counts of cells immunoreative with antibodies against phosphorylated tau (AD2, AT8, AT180, and AT100) and corresponding Western blot analysis. Results: Piericidin A significantly increased the number of phospho-tau immunoreactive cells in the cerebral cortex in P301S(+/+) mice, but only to a variable and mild extent in wild-type mice. Furthermore, piericidin A led to increased levels of pathologically phosphorylated tau only in P301S(+/+) mice. While we observed no apparent cell loss in the frontal cortex, the synaptic density was reduced by piericidin A treatment in P301S(+/+) mice. Discussion: This study shows that exposure to piericidin A aggravates the course of genetically determined tau pathology, providing experimental support for the concept of gene-environment interaction in the etiology of tauopathies.
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- Xu, H., et al.
(författare)
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Tau Silencing by siRNA in the P301S Mouse Model of Tauopathy
- 2014
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Ingår i: Current Gene Therapy. - : Bentham Science Publishers Ltd.. - 1566-5232. ; 14:5, s. 343-351
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Tidskriftsartikel (refereegranskat)abstract
- Suppression of tau protein expression has been shown to improve behavioral deficits in mouse models of tauopathies, offering an attractive therapeutic approach. Experimentally this had been achieved by switching off the promoters controlling the transgenic human tau gene (MAPT), which is not possible in human patients. The aim of the present study was therefore to evaluate the effectiveness of small interfering RNAs (siRNAs) and their cerebral delivery to suppress human tau expression in vivo, which might be a therapeutic option for human tauopathies. We used primary cortical neurons of transgenic mice expressing P301S-mutated human tau and Lund human mesencephalic (LUHMES) cells to validate the suppressive effect of siRNA in vitro. For measuring the effect in vivo, we stereotactically injected siRNA into the brains of P301S mice to reveal the suppression of tau by immunochemistry (AT180, MC1, and CP13 antibodies). We found that the Accell((TM)) SMART pool siRNA against MAPT can effectively suppress tau expression in vitro and in vivo without a specific delivery agent. The siRNA showed a moderate distribution in the hippocampus of mice after single injection. NeuN, GFAP, Iba-1, MHC II immunoreactivities and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay showed neither signs of neurotoxicity or neuroinflammation nor apoptosis when MAPT siRNA is present in the hippocampus. Our data suggest that siRNA against MAPT can serve as a potential tool for gene therapy in tauopathies.
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