Photodynamic therapy on microbial infections

• Grant number: 12/21203-4
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2013
• End date: September 30, 2015
• Field of knowledge: Engineering - Biomedical Engineering - Bioengineering
• Principal Investigator: Carla Raquel Fontana
• Grantee: Carla Raquel Fontana
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Photodynamic therapy has been advocated as an alternative to antimicrobial agents to suppress subgingival species and to treat periodontitis. Bacteria located within dense biofilms, such as those encountered in dental plaque, have been found to be relatively resistant to antimicrobial therapy. In the present study, we will investigate the ability of photodynamic therapy to reduce the number of bacteria in biofilms by comparing the photodynamic effects of different photossensitizers on human dental plaque microorganisms in the planktonic phase and in biofilms. Material and Methods: Dental plaque samples will be obtained from subjects with chronic periodontitis. Suspensions of plaque microorganisms will be sensitized with Photogem®, Curcumin, Photodithazine® (PDZ), Methylene blue or Nanoparticles MB (concentrations from 15 to 70 mg / mL) and then exposed to a specific light during 10 minutes. Multispecies microbial biofilms developed from the same plaque samples will also be exposed to those photossensitizers (concentrations from 40 to 70 ug / ml) at the same light conditions as their planktonic counterparts. After photodynamic therapy, survival fractions were calculated by counting the number of colony-forming units. Confocal microscopy technique will be applied to evaluate the behavior of PDT against bacterial infection. In addition, spectroscopic studies and degradation of photosensitizers will also be carried out by fluorescence detection. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE FREITAS, LAURA MARISE; SOARES, CHRISTIANE PIENNA; FONTANA, CARLA RAQUEL. Synergistic effect of photodynamic therapy and cisplatin: A novel approach for cervical cancer. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 140, p. 365-373, NOV 2014. (12/25414-0, 12/21203-4)

DE FREITAS, LAURA MARISE; FIORAMONTI CALIXTO, GIOVANA MARIA; CHORILLI, MARLUS; GIUSTI, JUCAIRA STELLA M.; BAGNATO, VANDERLEI SALVADOR; SOUKOS, NIKOLAOS S.; AMIJI, MANSOOR M.; FONTANA, CARLA RAQUEL. Polymeric Nanoparticle-Based Photodynamic Therapy for Chronic Periodontitis in Vivo. INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, v. 17, n. 5, MAY 2016. (12/21203-4)

RONQUI, MARIA RITA; FOGACA DE AGUIAR COLETTI, TATIANA MARIA STARCK; DE FREITAS, LAURA MARISE; MIRANDA, ELAINE TOSCANO; FONTANA, CARLA RAQUEL. Synergistic antimicrobial effect of photodynamic therapy and ciprofloxacin. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 158, p. 122-129, MAY 2016. (12/21203-4)