Bioactive Chitosan Nanoparticles and Photodynamic Therapy Inhibit Collagen Degradation In Vitro

Abstract

This study evaluated the ability of photodynamic therapy (PDT), chitosan nanoparticles (CSnp), or their combination, to inhibit bacterial collagenase-mediated degradation of collagen. Rat type 1 fibrillar collagen matrices were untreated or treated with 2.5% glutaraldehyde (GD), 2.5% GD followed by 1% CSnp, 1% CSnp, PDT, or 1% CSnp followed by PDT. Samples, except untreated controls, were exposed to Clostridium histolyticum collagenase. The soluble digestion products were assessed by hydroxyproline assay and the remaining adherent collagen was quantified by picrosirius red (PSR) staining. Collagen treated with CSnp, PDT, or a combination of CSnp and PDT, exhibited less degradation than controls. The abundance of post-treatment residual collagen correlated with the extent of degradation. Fourier transform infrared (FTIR) spectroscopy analysis showed that PDT treatment enhanced collagen cross-linking.Immunoblotting of sedimented CSnp indicated that CSnp and collagenase bound with low affinity. However, CSnp-bound collagenase showed a significant reduction in collagenolytic activity compared with controls.III

Antimicrobial Photodynamic Therapy against Endodontic Enterococcus faecalis and Candida albicans Mono and Mixed Biofilms in the Presence of Photosensitizers: A Comparative Study with Classical Endodontic Irrigants

“…It also presented the same antimicrobial potential than the clinically used classical irrigants, CHX and EDTA. It is worth mentioning that TBO (Seal et al, 2002; Bergmans et al, 2008; Rios et al, 2011) is available in the market under the name of Fotosan ® agent (Gambarini et al, 2011; Rios et al, 2011) and RB has been widely studied (Shrestha et al, 2012, 2014; Persadmehr et al, 2014). As expected, 3% NaOCl had the best final outcomes.…”

Photoactivation of curcumin and sodium hypochlorite to enhance antibiofilm efficacy in root canal dentin

“…The highly reactive oxygen species produced during photoactivation interact with the amino acids molecules in dentin collagen to promote cross-linking [25,26]. This increase in the number of intermolecular collagen bonds has been found to enhance the resistance of dentin collagen to bacteria-mediated enzymatic degradation and improve the fracture toughness of dentin [25][26][27]. Low-energy level red and near infrared light is known to penetrate dentin tissue/dentinal tubules without inducing untoward effects on dentin matrix [27].…”

Improve ICG Based Photodynamic Properties Through Conjugation of ICG Into Nano-Graphene Oxide Against Enterococcus faecalis

“…The available mechanical and chemical methods cannot fully eliminate bacterial pathogens during endodontic treatment (7,16), which has negative consequences on the treatment outcome (8,17). Enterococcus faecalis is the most common bacterial pathogen in secondary endodontic infections and periapical biofilms, and is frequently found in canals requiring retreatment (7,13).…”

“…Hence, new disinfection methods and standard endodontic antimicrobial procedures should be developed to increase the success rate of endodontic therapy (11,13) and preserve, and if possible enhance, the dentin chemical/mechanical stability through selective bactericidal properties (14). Photodynamic therapy (PDT) in combination with organic nanomaterials is a promising method to achieve such goals (8,11,15,16). PDT is a non-thermal photochemical reaction that includes the simultaneous presence of visible light, oxygen, and a dye or photosensitizer (PS) during which ROS formed through types I or II mechanisms may inactivate sub-cellular components of microbial cells (8,15,17).…”