Comparative Analysis of the Proteomic Profile of the Dental Pulp in Different Conditions. A Pilot Study.

This study aimed to quantitatively compare the difference in protein expression in the progression of pulp pathogenesis, as well as to describe the biological functions of proteins identified in pulp tissue. Samples were obtained from six patients treated at the Araçatuba School of Dentistry and were divided into three groups: normal pulp - from teeth extracted for orthodontic indication; inflamed pulp and necrotic pulp - from patients diagnosed with irreversible pulpitis and chronic apical periodontitis, respectively. After previous proteomic preparation, dental pulp samples were processed for label-free quantitative proteomic analysis in a nanoACQUITY UPLC-Xevo QTof MS system. The difference in expression between the groups was calculated using the Protein Lynx Global Service software using the Monte Carlo algorithm. A total of 465 human proteins were identified in all groups. The most expressed proteins in the inflamed pulp group in relation to the normal pulp group were hemoglobin, peroxiredoxins and immunoglobulins, whereas the less expressed were the tubulins. Expression levels of albumins, immunoglobulins and alpha-2-macroglobulin were higher in the necrotic pulp group than in the inflamed pulp group. As for the qualitative analysis, the most prevalent protein functions in the normal pulp group were metabolic and energetic pathways; in the inflamed pulp group: cellular communication and signal transduction; and regulation and repair of DNA/RNA, while in the necrotic pulp group proteins were associated with the immune response. Thus, proteomic analysis showed quantitative and qualitative differences in protein expression in different types of pulp conditions.

Perfil proteômico de bactérias presentes em canais radiculares de dentes com periodontite apical sintomática ou assintomática / Proteomic profile of bacteria present in root canals of teeth with symptomatic or asymptomatic apical periodontitis

As infecções endodônticas são causadas por uma comunidade multiespécie de bactérias. Com os métodos de identificação microbiológica e quantificação de endotoxinas, é difícil inferir a fisiologia, a função e a patogenicidade microbiana. Assim, a análise proteômica é uma técnica que pode revolucionar o estudo da patogênese das infecções endodônticas. O presente estudo tem por objetivo analisar o perfil proteômico de infecções endodônticas relacionadas a dentes com periodontite apical sintomática ou assintomática utilizando cromatografia líquida associada à espectrometria de Massas. A análise deste perfil proteômico visa a proporcionar a compreensão dos aspectos ecológicos e patogênicos do comportamento de comunidades bacterianas endodônticas através da identificação de proteínas expressas no referido ambiente no momento da coleta e a determinação da função dessas proteínas. Foram coletadas amostras de 18 pacientes encaminhados para tratamento de canal radicular ou tratamento de emergência na Faculdade de Odontologia de Araçatuba FOA ­ UNESP. Foram incluídos dentes com infecção endodôntica primária, sintomáticos ou assintomáticos. A identificação dos peptídeos foi feita num sistema nanoACQUITY UPLC-Xevo QTof MS system (Waters), a identificação das proteínas foi obtida utilizando o software Protein Lynx Global Server (PLGS) versão 3.0, utilizando o banco de dados de proteínas UniProtKB. A diferença de expressão entre os grupos foi obtida através do mesmo software, considerando-se p<0,05 para as proteínas subreguladas e 1-p>0,95 para as proteínas suprareguladas. Foram identificados um total de 2181 números de acessos entre fragmentos, isoformas e proteínas completas humana e 51 proteínas bacterianas e ambas foram classificadas quanto a sua função biológica, em relação às proteínas exclusivas de cada grupo, 347 proteínas foram identificadas no grupo sintomático. As funções biológicas mais prevalentes foram comunicação celular e transdução de sinais, seguidas pela resposta imune, observou-se diversas proteínas exclusivamente expressas no grupo sintomático, indicando a influência direta da periodontite sintomática na resposta do hospedeiro(AU)

Endodontic infections are caused by a multispecies community of bacteria. With microbiological identification methods and endotoxin quantification, it is difficult to infer physiology, function and microbial pathogenicity. Thus, proteomic analysis is a technique that can revolutionize the study of the pathogenesis of endodontic infections. The present study aims to analyze the proteomic profile of endodontic infections related to teeth with symptomatic or asymptomatic apical periodontitis using liquid chromatography associated with mass spectrometry. The analysis of this proteomic profile aims to provide an understanding of the ecological and pathogenic aspects of the behavior of endodontic bacterial communities by identifying proteins expressed in the said environment at the time of collection and determining the function of these proteins. Samples were collected from 18 patients referred for root canal treatment or emergency treatment at the School of Dentistry of Araçatuba FOA - UNESP. Teeth with primary endodontic infection, symptomatic or asymptomatic were included. The identification of peptides was made in a nanoACQUITY UPLC-Xevo QTof MS system (Waters) system, the identification of proteins was obtained using protein lynx global server (PLGS) software version 3.0, using the UniProtKB protein database. The difference in expression between the groups was obtained through the same software, considering p<0.05 for subregulated proteins and 1-p>0.95 for the superregulated proteins. A total of 2,181 access numbers were identified between human fragments, isoforms and complete proteins and 51 bacterial proteins, and both were classified as their biological function, in relation to the exclusive proteins of each group, 347 proteins were identified in the symptomatic group. The most prevalent biological functions were cellular communication and signal transduction, followed by the immune response, and several proteins were observed exclusively expressed in the symptomatic group, indicating the direct influence of symptomatic periodontitis on the host response(AU)