Exploring Photoactivated Disinfection-Induced Bystander Effects on Microbial Biofilms of Aggregatibacter actinomycetemcomitans

Title:Exploring Photoactivated Disinfection-Induced Bystander Effects on Microbial Biofilms of Aggregatibacter actinomycetemcomitans

Volume: 21 Issue: 6

Author(s): Maryam Pourhajibagher and Abbas Bahador*

Affiliation:

• Oral Microbiology Laboratory, Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; 3Fellowship in Clinical Laboratory Sciences, Iran University of Medical Sciences, Tehran,Iran

Keywords: Bystander effects, Aggregatibacter actinomycetemcomitans, photoactivated disinfection, antimicrobial photodynamic therapy, periodontitis, peri-implantitis.

Abstract: Background: Photoactivated disinfection (PAD) has been indicated as one of the potential methods for the initial periodontal therapy in periodontitis and peri-implantitis, which may have bystander effects on the viability of off-target cells.

Objective: In this article, we evaluated the effects of PAD-induced bystander on biofilm formation ability, metabolic activity, and gene expression level of Aggregatibacter actinomycetemcomitans as one of the bacteria involved in causing periodontitis and peri-implantitis.

Methods: Bystander effects induced by bacterial cell suspension (BCST) obtained from treated A. actinomycetemcomitans culture with indocyanine green (ICG)-PAD on biofilm formation of A. actinomycetemcomitans were determined using microbial viability assay. Additionally, metabolic activity and changes in gene expression of fimA were assessed using the XTT reduction method and quantitative real-time PCR (qRT-PCR) assay, respectively.

Results: The results revealed that 1000 and 125 μg/mL of ICG combined with diode laser irradiation for 1 min were significant and sub-significant reduction doses of ICG-PAD, respectively, versus A. actinomycetemcomitans. The biofilm formation ability, metabolic activity, as well as, expression level of fimA gene in A. actinomycetemcomitans were significantly reduced after treatment by a significant reduction dose of ICG-PAD-induced bystander effects (P<0.05).

Conclusion: ICG-PAD could significantly reduce the microbial population, cell metabolic activity, and gene expression through the bystander effects and could enhance the efficiency of PAD as an adjunct approach for the nonsurgical treatment of periodontitis and peri-implantitis.

Cite this article as:

Pourhajibagher Maryam and Bahador Abbas *, Exploring Photoactivated Disinfection-Induced Bystander Effects on Microbial Biofilms of Aggregatibacter actinomycetemcomitans, Infectious Disorders - Drug Targets 2021; 21 (6) : e170721187710 . https://dx.doi.org/10.2174/1871526520666201109120323