RESUMO
Inhibition of insulin-degrading enzyme (IDE) is a possible target for treating diabetes. However, it has not yet evolved into a medical intervention, mainly because most developed inhibitors target the zinc in IDE's catalytic site, potentially causing toxicity to other essential metalloproteases. Since IDE is a cellular receptor for the varicella-zoster virus (VZV), we constructed a VZV-based inhibitor. We computationally characterized its interaction site with IDE showing that the peptide specifically binds inside IDE's central cavity, however, not in close proximity to the zinc ion. We confirmed the peptide's effective inhibition on IDE activity in vitro and showed its efficacy in ameliorating insulin-related defects in types 1 and 2 diabetes mouse models. In addition, we suggest that inhibition of IDE may ameliorate the pro-inflammatory profile of CD4+ T-cells toward insulin. Together, we propose a potential role of a designed VZV-derived peptide to serve as a selectively-targeted and as an efficient diabetes therapy.
Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Insulina/metabolismo , Insulisina/antagonistas & inibidores , Fragmentos de Peptídeos/administração & dosagem , Proteínas do Envelope Viral/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/patologia , Inibidores Enzimáticos/administração & dosagem , Feminino , Herpesvirus Humano 3/fisiologia , Insulisina/genética , Insulisina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos KnockoutRESUMO
Importance: Administration of a BNT162b2 booster dose (Pfizer-BioNTech) to fully vaccinated individuals aged 60 years and older was significantly associated with lower risk of SARS-CoV-2 infection and severe illness. Data are lacking on the effectiveness of booster doses for younger individuals and health care workers. Objective: To estimate the association of a BNT162b2 booster dose with SARS-CoV-2 infections among health care workers who were previously vaccinated with a 2-dose series of BNT162b2. Design, Setting, and Participants: This was a prospective cohort study conducted at a tertiary medical center in Tel Aviv, Israel. The study cohort included 1928 immunocompetent health care workers who were previously vaccinated with a 2-dose series of BNT162b2, and had enrolled between August 8 and 19, 2021, with final follow-up reported through September 20, 2021. Screening for SARS-CoV-2 infection was performed every 14 days. Anti-spike protein receptor binding domain IgG titers were determined at baseline and 1 month after enrollment. Cox regression with time-dependent analysis was used to estimate hazard ratios of SARS-CoV-2 infection between booster-immunized status and 2-dose vaccinated (booster-nonimmunized) status. Exposures: Vaccination with a booster dose of BNT162b2 vaccine. Main Outcomes and Measures: The primary outcome was SARS-CoV-2 infection, as confirmed by reverse transcriptase-polymerase chain reaction. Results: Among 1928 participants, the median age was 44 years (IQR, 36-52 years) and 1381 were women (71.6%). Participants completed the 2-dose vaccination series a median of 210 days (IQR, 205-213 days) before study enrollment. A total of 1650 participants (85.6%) received the booster dose. During a median follow-up of 39 days (IQR, 35-41 days), SARS-CoV-2 infection occurred in 44 participants (incidence rate, 60.2 per 100â¯000 person-days); 31 (70.5%) were symptomatic. Five SARS-CoV-2 infections occurred in booster-immunized participants and 39 in booster-nonimmunized participants (incidence rate, 12.8 vs 116 per 100â¯000 person-days, respectively). In a time-dependent Cox regression analysis, the adjusted hazard ratio of SARS-CoV-2 infection for booster-immunized vs booster-nonimmunized participants was 0.07 (95% CI, 0.02-0.20). Conclusions and Relevance: Among health care workers at a single center in Israel who were previously vaccinated with a 2-dose series of BNT162b2, administration of a booster dose compared with not receiving one was associated with a significantly lower rate of SARS-CoV-2 infection over a median of 39 days of follow-up. Ongoing surveillance is required to assess durability of the findings.
Assuntos
Anticorpos Antivirais/sangue , Vacina BNT162/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/epidemiologia , Pessoal de Saúde/estatística & dados numéricos , Eficácia de Vacinas , Adulto , Idoso , Vacina BNT162/imunologia , COVID-19/diagnóstico , COVID-19/prevenção & controle , Teste de Ácido Nucleico para COVID-19 , Feminino , Humanos , Imunização Secundária , Imunoglobulina G/sangue , Incidência , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
BACKGROUND: Numerous disorders affecting the optic nerve require histological examination of whole length optic nerves and chiasm. Most methods employed to study the histopathology of the optic nerves in animal models of human diseases involve resection of a short retrobulbar section after eye globe exenteration, commonly obtained in mice. This approach might affect the morphology of the optic nerve, thus limiting accurate identification of pathological changes in the tissue. Some histological studies were performed on longer or more posterior parts of the anterior visual pathway included the chiasm. However, an accurate replicable protocol for such whole length (eye globe to chiasm) dissection is currently unavailable in published literature. NEW METHOD: Here we describe a protocol for dissecting the whole length of the optic nerves and chiasm through a craniotomy incision. RESULTS: We describe in detail the stages necessary for exposing the optic nerves, the chiasm and the optic tracts, and for detaching them with minimal traction. COMPARISON WITH EXISTING METHOD: The existing replicable method provide only a sample of the retrobulbar optic nerve and the sample might be affected by traction. Our protocol provides a whole length specimen of the optic nerve and chiasm without concern of traction artifacts. CONCLUSIONS: We present a simple and straightforward approach to isolate the complete anterior visual pathway in the mouse for histopathological evaluation.