The role of an acidic beverage on the activation of human salivary matrix metalloproteinases (MMPs)

• Grant number: 10/05780-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2010
• End date: December 31, 2010
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Marília Afonso Rabelo Buzalaf
• Grantee: Bruno Lara Zarella
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

Acidic drinks are important in erosion pathogenesis, and the mechanism of action has so far been thought to be based only on the acidity of the drinks. Since it has been demonstrated the role of MMP inhibition on the progression of erosive lesions in dentin, the aim of this study is to examine the potential for an acidic beverage to activate human gelatinolytic MMPs present in human saliva. Paraffin-stimulated whole saliva will be collected from healthy volunteers and centrifuged (10,000 rpm, 10 min), and the supernatant will be used for the experiments. Aliquots of pure saliva or saliva diluted in cola drink (1:5 v/v) which provides a pH of 4.0 will be immediately rediluted in non-reducing sample buffer (10:3 sample:sample buffer). Additionally, part of diluted samples at pH 4.0 will be neutralized (pH 7.0) by addition of NaOH. All samples will be incubated for 1 h at 37ºC and then submitted to zymography analysis in triplicate. The total MMP-2 and -9 activities will be determined by specific activity assay kits.