Proteomic analysis of acquired pellicle formed on experimental composite resins containing or not filler and/or protease inhibitors: study in situ

Author(s)

Vinicius Taioqui Pelá

• Document type: Master's Dissertation
• Press: Bauru.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Bauru (FOB/SDB)
• Defense date: 2017-05-19

Examining board members

Marilia Afonso Rabelo Buzalaf; Daniela Rios Honório; Rafael Rodrigues Lima; Juliano Pelim Pessan

• Advisor: Marilia Afonso Rabelo Buzalaf

Abstract

In the oral cavity, any exposed surface is prone to the formation of the acquired pellicle (AP), an organic film, free of bacteria, which is formed in vivo as a result of the selective adsorption of salivary proteins and glycoproteins to the solid surfaces exposed to the oral environment. The objective of this work was to evaluate the influence of the addition or not of filler (Barium glass alumina silicate and silica) and/or protease inhibitors [epigallocatechin-3-gallate (EGCG) or chlorhexidine (CHX)] to experimental composite resins in the protein profile of the AP formed on these specimens, using quantitative label-free proteomic analysis. Three-hundred and twenty-four samples of bovine enamel (6x6x2mm) were prepared. A cavity (4x4mm) was made, filled with experimental resins and divided into 6 groups of 54 specimens each, according to the experimental groups: no filler, no inhibitor (NF-NI); filler, no inhibitor (F-NI); no filler plus CHX (NF-CHX); filler plus CHX (F-CHX); no filler plus EGCG (NF-EGCG); filler plus EGCG (F-EGCG). Nine young adults of both genders participated using a removable jaw appliance (BISPM - Bauru in situ pellicle model)) with 2 slabs of each group. The experiment was carried out in 9 consecutive days, during the morning for 120 minutes. The pellicle was obtained through the aid of electrodes filter paper moistened in 3% citric acid. The pellicles collected were processed for analysis by LC-ESI-MS/MS. The obtained MS/MS spectra were searched against human protein database (SWISSPROT). The proteomic data related to protein quantification were analyzed using the PLGS software. Difference in expression among the groups was expressed as p<0.05 for down-regulated proteins and 1-p>0.95 for up-regulated proteins. A total of 140 proteins were identified in the AP. From these, 16 were found in all the groups, among which are many proteins typically found in the AP, such as two isoforms of Basic salivary proline-rich protein, Cystatin-S, Cystatin-AS, Cystatin-SN, Histatin-1, Ig alpha-1 chain C region, Lysozyme C, Mucin-7, Proline-rich protein 4, Protein S100-A9, Salivary acidic proline-rich phosphoprotein ½, Statherin and Submaxillary gland androgen-regulated protein 3B. The total number of proteins identified in each group was 31, 51, 18, 38, 106 and 54 for NF-NI, F-NI, NF-CHX, F-CHX, NF-EGCG and F-EGCG, respectively. The respective amount of proteins exclusively in each group was 6, 14, 1, 6, 51 and 5. Most of the proteins that are not commonly described in the AP that have distinct functions in the organism, being involved in metabolism, cell signaling, cell adhesion, cell division, transport, protein synthesis and degradation were found most prominently in the NF-EGCG group. These results demonstrate that there was a difference in the protein profile of the AP due to the composition of the experimental resins, beyond offering important information on the development of restorative materials with components that can increase the protection in the oral cavity. (AU)

• FAPESP's process: 14/25599-5 - PROTEOMIC ANALYSIS OF ACQUIRED PELLICLE FORMED ON EXPERIMENTAL COMPOSITE RESINS CONTAINING OR NOT FILLER AND/OR PROTEASE INHIBITORS
• Grantee: Vinícius Taioqui Pelá
• Support Opportunities: Scholarships in Brazil - Master