Biological analysis, expression of surface markers and antimicrobial activity of titanium-molybdenum alloy in contact with human mesenchymal stem cells (ADSC) or co-culture of osteoblasts and osteoclasts.

• Grant number: 16/13155-0
• Support Opportunities: Scholarships abroad - Research
• Start date: January 23, 2017
• End date: December 22, 2017
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Samira Esteves Afonso Camargo
• Grantee: Samira Esteves Afonso Camargo
• Host Investigator: Ketul C Popat
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil
• Institution abroad: Colorado State University, United States

Abstract

This study will evaluate the biological properties of nanotube alloys (Ti 7.5Mo) with or without chlorhexidine treatment surface of human adipose derived stem cells (ADSC) using cytotoxicity (WST-1) and genotoxicity (micronucleus test) assays and evaluation of the antimicrobial activity of fungus, aerobic and anaerobic microorganisms. It will be analyzed the quantative expression of alkaline phosphatase (ALP) activity, osteocalcin (OC), osteopontin (OP), osteonectin (ON) and RANKL by confocal fluorescence microscopy on co-culture of osteoblasts and osteoclasts or isolated cultures of osteoblasts and osteoclasts. It will be established three groups of titanium-molybdenum alloys: Ti 7.5Mo without chlorhexidine; Ti 7.5Mo + 0.2% chlorhexidine; Ti 7.5Mo + 2% chlorhexidine. ADSC cells will be exposed to Ti-7.5Mo alloys for 24 h, 4 and 7 days and cell survival will be measured by WST-1 assay in a spectrophotometer. Genotoxicity will be determined by the formation of micronuclei in cells after 24 h of exposure to Ti-7.5Mo alloys and sulfanate ethylmethane (positive control). The antimicrobial activity of Ti-7.5Mo alloys will be evaluated on planktonic culture and biofilm of Candida albicans, Enterococcus faecalis, Streptococcus mutans, Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum. The expression of surface markers will be evaluated on co-culture of osteoblasts and osteoclasts in contact with Ti-7.5Mo alloys for different periods using a fluorescence confocal microscopy (Nikon) and quantitative analyses using Image J software. The results will be evaluated by ANOVA, Tukey's and Mann-Whitney-U tests (p<0.05).