RESUMO
Protein misfolding and aggregation is observed in many amyloidogenic diseases affecting either the central nervous system or a variety of peripheral tissues. Structural and dynamic characterization of all species along the pathways from monomers to fibrils is challenging by experimental and computational means because they involve intrinsically disordered proteins in most diseases. Yet understanding how amyloid species become toxic is the challenge in developing a treatment for these diseases. Here we review what computer, in vitro, in vivo, and pharmacological experiments tell us about the accumulation and deposition of the oligomers of the (Aß, tau), α-synuclein, IAPP, and superoxide dismutase 1 proteins, which have been the mainstream concept underlying Alzheimer's disease (AD), Parkinson's disease (PD), type II diabetes (T2D), and amyotrophic lateral sclerosis (ALS) research, respectively, for many years.
Assuntos
Amiloide/química , Amiloide/metabolismo , Doenças Neurodegenerativas/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Modelos Moleculares , Doenças Neurodegenerativas/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Agregação Patológica de Proteínas , Deficiências na Proteostase/metabolismo , Superóxido Dismutase-1/química , Superóxido Dismutase-1/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Proteínas tau/química , Proteínas tau/metabolismoRESUMO
INTRODUCTION: Helicobacter pylori express a large array of antigens, each of which is duly responsible for successful colonization and pathogenesis. Here, we have studied host serum antibody responses to four of its immunodominant antigens in association with the infection status and the resulting clinical outcomes. METHODS: For this purpose, four individual H. pylori proteins (UreB, CagA, Tip-α and HP0175) were produced in recombinant forms. Serum antibody responses of 246 (75â¯GC and 171 NUD) patients, against the above antigens, were evaluated by multiplex immunoblotting. The associations between the resulting data and the infection status, as well as clinical outcomes were evaluated using logistic regression models. RESULTS: Serum antibodies to all four recombinant antigens increased the chances of detecting screening ELISA-positive subjects, in an escalating dose-dependent manner, ranging from 2.6 (1.5-4.7) for HP0175 to 14.3 for UreB (4.3-50.7), exhibiting the lowest and highest odds ratios, respectively (PAdjâ¯≤â¯0.001), such that 98.2% of the subjects with antibodies to all four antigens, were also positive by the screening ELISA (Pâ¯<â¯0.0001). Among the screening ELISA-positive subjects, the three antigens of CagA, Tip-α, and HP0175 were able to segregate current from past H. pylori infection (Pâ¯<â¯0.05). Accordingly, subjects with antibodies to one or more antigen(s) were at 5.4 (95% CI: 1.8-16.4) folds increased chances of having current infection, as compared to triple negatives (PAdjâ¯=â¯0.003). In reference to the clinical outcomes, those with serum antibodies to CagA were more prevalent among gastric cancer, as compared to NUD patients (ORAdj: 5.4, 95% CI: 2.4-12.2, PAdjâ¯<â¯0.0001). When NUD patients were categorized according to their histopathologic status, multiple antigen analysis revealed that subjects with serum antibodies to one or more of the 3 current infection-positive antigens (CagA, Tip-α, and HP0175) were at 9.7 (95% CI: 2.1-44.9, Pâ¯=â¯0.004) folds increased risk of atrophic gastritis, in reference to triple negatives. CONCLUSION: The non-invasive multiplex serology assay, presented here, was able to not only detect subjects with current H. pylori infection, it could also screen dyspeptic patients for the presence of gastric atrophy. This simple and cost-efficient method can supplement routine screening ELISAs, to increase the chances of detecting current infections as well as atrophic gastritis.