title: Sera of patients with celiac disease and neurologic disorders evoke a mitochondrial-dependent apoptosis in vitro.
abstract: OBJECTIVE
  The mechanisms underlying neurologic impairment in celiac disease remain unknown. We tested whether antineuronal antibody-positive sera of patients with celiac disease evoke neurodegeneration via apoptosis in vitro.
  
  
  METHODS
  SH-Sy5Y cells were exposed to crude sera, isolated immunoglobulin (Ig) G and IgG-depleted sera of patients with and without celiac disease with and without neurologic disorders, and antineuronal antibodies. Adsorption studies with gliadin and tissue transglutaminase (tTG) were performed in celiac disease sera. Apoptosis activated caspase-3, apaf-1, Bax, cytochrome c, cleaved caspase-8 and caspase-9 and mitochondrial respiratory chain complexes were evaluated with different methods.
  
  
  RESULTS
  SH-Sy5Y cells exposed to antineuronal antibody-positive sera and isolated IgG from the same sera exhibited a greater percentage of TUNEL-positive nuclei than that of antineuronal antibody-negative sera. Neuroblasts exposed to antineuronal antibody-negative celiac disease sera also showed greater TUNEL positivity and apaf-1 immunolabeled cells than controls. Antigliadin- and anti-tTG-depleted celiac disease sera had an apoptotic effect similar to controls. Anti-caspase-3 immunostained cells were greater than controls when exposed to positive sera. The mitochondrial respiratory chain complex was reduced by positive sera. Western blot demonstrated only caspase-9 cleavage in positive sera. Cytochrome c and Bax showed reciprocal translocation (from mitochondria to cytoplasm and vice versa) after treatment with positive sera.
  
  
  CONCLUSIONS
  Antineuronal antibodies and, to a lower extent, combined antigliadin and anti-tTG antibodies in celiac disease sera contribute to neurologic impairment via apoptosis. Apaf-1 activation with Bax and cytochrome c translocation suggest a mitochondrial-dependent apoptosis.
authors.affiliation: Department of Physiological & Pharmacological Sciences, University of Pavia, Pavia, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Cervio
authors.forename: Umberto
authors.initials: U
authors.lastname: Volta
authors.forename: Manuela
authors.initials: M
authors.lastname: Verri
authors.forename: Federica
authors.initials: F
authors.lastname: Boschi
authors.forename: Ornella
authors.initials: O
authors.lastname: Pastoris
authors.forename: Alessandro
authors.initials: A
authors.lastname: Granito
authors.forename: Giovanni
authors.initials: G
authors.lastname: Barbara
authors.forename: Claudia
authors.initials: C
authors.lastname: Parisi
authors.forename: Cristina
authors.initials: C
authors.lastname: Felicani
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonini
authors.forename: Roberto
authors.initials: R
authors.lastname: De Giorgio
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000276:immunology*; D053477:Apoptotic Protease-Activating Factor 1 / Q000378:metabolism; D006690:Bisbenzimidazole; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002446:Celiac Disease / Q000097:blood / Q000276:immunology* / Q000473:pathology*; D045744:Cell Line, Tumor; D002950:Citrate (si)-Synthase / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D042967:Electron Transport Complex I / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000378:metabolism*; D009410:Nerve Degeneration / Q000276:immunology* / Q000473:pathology; D009447:Neuroblastoma; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C506592:APAF1 protein, human; D053477:Apoptotic Protease-Activating Factor 1; C494826:BAX protein, human; D005456:Fluorescent Dyes; D007074:Immunoglobulin G; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D002950:Citrate (si)-Synthase; D053148:Caspase 3; D053453:Caspase 9; D042967:Electron Transport Complex I; D006690:Bisbenzimidazole