3 results on '"Fraering, Jeremy"'
Search Results
2. Induction of Amyloid-β42 Production by Fipronil and Other Pyrazole Insecticides
- Author
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Cam, Morgane, Durieu, Emilie, Bodin, Marion, Manousopoulou, Antigoni, Koslowski, Svenja, Vasylieva, Natalia, Barnych, Bogdan, Hammock, Bruce D, Bohl, Bettina, Koch, Philipp, Omori, Chiori, Yamamoto, Kazuo, Hata, Saori, Suzuki, Toshiharu, Karg, Frank, Gizzi, Patrick, Haber, Vesna Erakovic, Mihaljevic, Vlatka Bencetic, Tavcar, Branka, Portelius, Erik, Pannee, Josef, Blennow, Kaj, Zetterberg, Henrik, Garbis, Spiros D, Auvray, Pierrick, Gerber, Hermeto, Fraering, Jeremy, Fraering, Patrick C, and Meijer, Laurent
- Subjects
Biomedical and Clinical Sciences ,Biological Psychology ,Clinical Sciences ,Neurosciences ,Psychology ,Alzheimer's Disease ,Brain Disorders ,Dementia ,Acquired Cognitive Impairment ,Aging ,Neurodegenerative ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,2.1 Biological and endogenous factors ,Neurological ,Adipose Tissue ,Alzheimer Disease ,Amyloid Precursor Protein Secretases ,Amyloid beta-Peptides ,Animals ,Brain ,Environmental Exposure ,HEK293 Cells ,Humans ,Induced Pluripotent Stem Cells ,Insecticides ,Mice ,Neurons ,Peptide Fragments ,Proteome ,Pyrazoles ,Rats ,A beta(38) ,A beta(40) ,A beta(42) ,A beta(43) ,A beta(42)/A beta(40) ratio ,aftins ,Alzheimer's disease ,alzheimerogen ,amyloid-beta ,amyloid-beta protein precursor ,fipronil ,gamma-secretase ,human chemical exposome ,pesticides ,phenylpyrazoles ,prevention ,pyrazoles ,triazines ,Alzheimer’s disease ,Aβ38 ,Aβ40 ,Aβ42 ,Aβ42/Aβ40 ratio ,Aβ43 ,amyloid-β ,amyloid-β protein precursor ,γ-secretase ,Cognitive Sciences ,Neurology & Neurosurgery ,Clinical sciences ,Biological psychology - Abstract
Generation of amyloid-β peptides (Aβs) by proteolytic cleavage of the amyloid-β protein precursor (AβPP), especially increased production of Aβ42/Aβ43 over Aβ40, and their aggregation as oligomers and plaques, represent a characteristic feature of Alzheimer's disease (AD). In familial AD (FAD), altered Aβ production originates from specific mutations of AβPP or presenilins 1/2 (PS1/PS2), the catalytic subunits of γ-secretase. In sporadic AD, the origin of altered production of Aβs remains unknown. We hypothesize that the 'human chemical exposome' contains products able to favor the production of Aβ42/Aβ43 over Aβ40 and shorter Aβs. To detect such products, we screened a library of 3500 + compounds in a cell-based assay for enhanced Aβ42/Aβ43 production. Nine pyrazole insecticides were found to induce a β- and γ-secretase-dependent, 3-10-fold increase in the production of extracellular Aβ42 in various cell lines and neurons differentiated from induced pluripotent stem cells derived from healthy and FAD patients. Immunoprecipitation/mass spectrometry analyses showed increased production of Aβs cleaved at positions 42/43, and reduced production of peptides cleaved at positions 38 and shorter. Strongly supporting a direct effect on γ-secretase activity, pyrazoles shifted the cleavage pattern of another γ-secretase substrate, alcadeinα, and shifted the cleavage of AβPP by highly purified γ-secretase toward Aβ42/Aβ43. Focusing on fipronil, we showed that some of its metabolites, in particular the persistent fipronil sulfone, also favor the production of Aβ42/Aβ43 in both cell-based and cell-free systems. Fipronil administered orally to mice and rats is known to be metabolized rapidly, mostly to fipronil sulfone, which stably accumulates in adipose tissue and brain. In conclusion, several widely used pyrazole insecticides enhance the production of toxic, aggregation prone Aβ42/Aβ43 peptides, suggesting the possible existence of environmental "Alzheimerogens" which may contribute to the initiation and propagation of the amyloidogenic process in sporadic AD.
- Published
- 2018
3. PfEMP1 A-type ICAM-1-binding domains are not associated with cerebral Malaria in Beninese children
- Author
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Joste, V., Guillochon, E., Fraering, Jeremy, Vianou, B., Watier, L., Guemouri, Sayeh, Cot, Michel, Houze, S., Aubouy, Agnès, Faucher, J. F., Argy, N., Bertin, Gwladys, and NeuroCM Study Group
- Subjects
dual receptor binding ,ICAM-1-binding motif ,var genes ,parasitic diseases ,cytoadherence ,cerebral malaria - Abstract
PfEMP1 is the major antigen involved in Plasmodium falciparum-infected erythrocyte sequestration in cerebrovascular endothelium. While some PfEMP1 domains have been associated with clinical phenotypes of malaria, formal associations between the expression of a specific domain and the adhesion properties of clinical isolates are limited. In this context, 73 cerebral malaria (CM) and 98 uncomplicated malaria (UM) Beninese children were recruited. We attempted to correlate the cytoadherence phenotype of Plasmodium falciparum isolates with the clinical presentation and the expression of specific PfEMP1 domains. Cytoadherence level on Hbec-5i and CHO-ICAM-1 cell lines and var genes expression were measured. We also investigated the prevalence of the ICAM-1-binding amino acid motif and dual receptor-binding domains, described as a potential determinant of cerebral malaria pathophysiology. We finally evaluated IgG levels against PfEMP1 recombinant domains (CIDR alpha 1.4, DBL beta 3, and CIDR alpha 1.4-DBL beta 3). CM isolates displayed higher cytoadherence levels on both cell lines, and we found a correlation between CIDR alpha 1.4 DBL beta 1/3 domain expression and CHO-ICAM-1 cytoadherence level. Endothelial protein C receptor (EPCR)-binding domains were overexpressed in CM isolates compared to UM whereas no difference was found in ICAM-1-binding DBL beta 1/3 domain expression. Surprisingly, both CM and UM isolates expressed ICAM-1-binding motif and dual receptor-binding domains. There was no difference in IgG response against DBL beta 3 between CM and UM isolates expressing ICAM-1-binding DB4 beta/3 domain. It raises questions about the role of this motif in CM pathophysiology, and further studies are needed, especially on the role of DBL beta 1/3 without the ICAM-1-binding motif. IMPORTANCE Cerebral malaria pathophysiology remains unknown despite extensive research. PfEMP1 proteins have been identified as the main Plasmodium antigen involved in cerebrovascular endothelium sequestration, but it is unclear which var gene domain is involved in Plasmodium cytoadhesion. EPCR binding is a major determinant of cerebral malaria whereas the ICAM-1-binding role is still questioned. Our study confirmed the EPCR-binding role in CM pathophysiology with a major overexpression of EPCR-binding domains in CM isolates. In contrast, ICAM-1-binding involvement appears less obvious with A-type ICAM-1-binding and dual receptor-binding domain expression in both CM and UM isolates. We did not find any variations in ICAM-1-binding motif sequences in CM compared to UM isolates. UM and CM patients infected with isolates expressing the ICAM-1-binding motif displayed similar IgG levels against DBL beta 3 recombinant protein. Our study raises interrogations about the role of these domains in CM physiopathology and questions their use in vaccine strategies against cerebral malaria.
- Published
- 2020
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