Attenuation of Aggregatibacter actinomycetemcomitans virulence using curcumin-decorated nanophytosomes-mediated photo-sonoantimicrobial chemotherapy

This study aimed to focus on the simultaneous use of antimicrobial photodynamic therapy (aPDT) and sonodynamic antimicrobial chemotherapy (SACT), which is called photo-sonodynamic antimicrobial chemotherapy (PSACT) to attenuate the virulence of Aggregatibacter actinomycetemcomitans. Following the synthesis of Curcumin-decorated nanophytosomes (Cur-NPhs) as a novel photo-sonosensitizer, its particle size, polydispersity, ζ-potential surface morphology, physical stability, drug release, and entrapment efficiency were determined. In the Cur-NPhs-PSACT, the antimicrobial activities of Cur-NPhs against A. actinomycetemcomitans were investigated using cell viability, biofilm killing/degradation, metabolic activity, expression of quorum-sensing-associated qseB and qseC genes, and biofilm-associated rcpA gene under blue laser irradiation plus ultrasonic waves. Characterization tests showed the presence of a sphere-shaped vesicle and the self-closed structure of Cur-NPhs, resulting in a high drug-loading content and encapsulation efficiency. However, the antimicrobial effect of Cur-NPhs-PSACT was dose-dependent, PSACT using the high concentrations of Cur-NPhs (50 � 10�4 g/L) showed significant reductions (P < 0.05) in cell viability (13.6 log10 CFU/mL), biofilm killing/degradation (65), metabolic activity (89.6,), and mRNA levels of virulence determinant genes (qseB; 9.8-fold, qseC; 10.2-fold, and recA; 10.2-fold). This study concludes that the Cur-NPhs-PSACT had antimicrobial activities against A. actinomycetemcomitans by downregulating the expression of virulence genes, and may attenuate this bacterium that decreases periodontal disease severity in patients. © 2021, The Author(s)

Robust antimicrobial photodynamic therapy with curcumin-poly (lactic-co-glycolic acid) nanoparticles against COVID-19: A preliminary in vitro study in Vero cell line as a model

Background: In this study, the ability of antimicrobial photodynamic therapy (aPDT) as a treatment approach and adjuvant therapy using curcumin-poly (lactic-co-glycolic acid) nanoparticles (Cur@PLGA-NPs) to inactivate Coronavirus disease 2019 (COVID-19) in plasma was investigated. Furthermore, to verify whether the quality requirement of aPDT-treated plasma is acceptable, the differences of the levels of clotting factors, total plasma proteins, and anti-A and/or anti-B antibodies titrations in plasma of patient before and after aPDT treatment were investigated. Materials and Methods: Cur@PLGA-NPs was synthesized using Electrospinning process and characterized by different analysis including Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), and Fourier Transform Infrared (FTIR) spectroscopy assays. The presence of the SARS-CoV-2 in the plasma samples of patients suspected of having COVID-19 was confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR) assay. Then, the treated plasma samples with Cur@PLGA-NPs plus blue laser were exposed to Vero cells. Eventually, cell cytotoxicity and apoptotic effects of treated Vero cells were evaluated. Levels of clotting factors including prothrombin time (PT) and activated partial thromboplastin time (APTT), total plasma proteins, and anti-A and/or anti-B antibodies measurements were performed using the coagulometer, method of Bradford, and titration procedure, respectively. Results: The presence of SARS-CoV-2 was positive in 84.3 of samples. Different concentrations of Cur@PLGA-NPs (3, 5, 7, and 10 wt.), the irradiation times of blue laser (1, 3, and 5 min), and aPDT with the maximum dosed of blue laser light (522.8 J/cm2) plus 10 wt. Cur@PLGA-NPs had no cytotoxicity. Although there were significant cell degradation and apoptotic effects in treated Vero cells with treated plasma using 10 wt. Cur@PLGA-NPs, and a blue laser at an energy density of 522.8 J/cm2, no visible changes in cells and apoptosis were observed following aPDT. Total plasma protein content, PT, APTT, and anti-A and/or anti-B antibodies titers showed no significant changes (P > 0.05 for all comparisons) in treated plasma as compared to untreated plasma. Conclusion: aPDT exhibited in vitro anti-COVID-19 activities in the treated plasma containing SARS-COV-2 without Vero cell apoptosis and any adverse effects on plasma quality in aPDT-exposed plasma. © 2021 Elsevier B.V

In vitro antibacterial activity and durability of a nano-curcumin-containing pulp capping agent combined with antimicrobial photodynamic therapy

Background: Considering the antibacterial properties of nano-curcumin (nCur) reinforced with antimicrobial photodynamic therapy (aPDT), this study aimed to assess the antibacterial activity and durability of Activa BioActive Base/Liner (ABBL) containing nCur (nCur-ABBL) as a pulp capping agent against Streptococcus mutans, the most common cause of secondary caries. Materials and methods: In this in vitro experimental study, ABBL discs containing 0.5 , 1, 2, and 5 (w/w) concentrations of nCur were fabricated. After aPDT using light emitting diode (LED) at 435 +/- 20 nm wavelength for 5 min, the discs were undergone aging in artificial saliva for 90 days. The antibacterial activity of the discs against S. mutans was evaluated by the disc agar diffusion test, and the number of bacterial colonies present in the biofilm formed on the disc surfaces was counted after 0, 15, 30, and 60 days of aging. Results: The maximum growth inhibition zone was noted around the 5 nCur-ABBL discs. Increasing the con-centration of nCur from 0.5 to 5 combined with aPDT significantly decreased the number of S. mutans colonies in the biofilm over time (P 0.05). Conclusion: According to our data, 5 nCur-ABBL revealed the largest growth inhibition zone in S. mutans culture. Moreover, 5 nCur can serve as an excellent ABBL additive in aPDT producer against S. mutans biofilms up to 60 days of aging period

Expression patterns of oxyR induced by oxidative stress from Porphyromonas gingivalis in response to photo-activated disinfection

Maryam Pourhajibagher,1–3 Roghayeh Ghorbanzadeh,4 Abbas Bahador1,3,5 1Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; 2Dental Implant Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; 3Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; 4Private Practice, Tehran, Iran; 5Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran Introduction: Porphyromonas gingivalis, an important endodontic pathogen, may be exposed to sublethal doses of photo-activated disinfection (sPAD) during root canal therapy. Such an exposure can affect bacterial survival and virulence features. In this study, we evaluated the effect of sPAD-related oxidative stresses on the expression of oxidative stress response gene (oxyR) in P. gingivalis clinical isolates surviving in vitro photodynamic treatment. Materials and methods: To determine the sPAD, 16 clinical P. gingivalis isolates photosensitized with toluidine blue O (TBO), methylene blue (MB), and indocyanine green (ICG) were irradiated with specific wavelength and energy density of diode laser corresponding to the photosensitizers following bacterial viability measurements. The effects of sPAD on the expression ratio of oxyR of 16 clinical P. gingivalis isolates were then assessed using quantitative real-time PCR (qRT-PCR) assay. Results: Maximum values of sPAD against P. gingivalis were 6.25, 15.6, and 25 µg/mL at fluencies of 171.87, 15.6, and 93.75 J/cm2, respectively, for TBO-, ICG-, and MB-sPAD (P>0.05). ICG-, MB-, and TBO-sPAD could increase the oxyR gene expression of the clinical P. gingivalis isolates 12.3-, 5.6-, and 8.5-fold, respectively. ICG-sPAD increased the expression of oxyR gene in clinical isolates of P. gingivalis ~1.5- and 2-fold higher than TBO- and MB-sPAD, respectively. Conclusion: Our results showed that upregulation of oxyR during sPAD may lead to better survival and increased pathogenicity of P. gingivalis isolates. Therefore, selection of appropriate photo-activated disinfection dosage should be considered for the successful treatment of endodontic infection. Keywords: antimicrobial photodynamic therapy, indocyanine green, methylene blue, oxidative stress, Porphyromonas gingivalis, toluidine blue O, low-level laser therap

Antimicrobial effects and mechanical properties of poly(methyl methacrylate) as an orthodontic acrylic resin containing Curcumin-Nisin-poly(l-lactic acid) nanoparticle: an in vitro study

Background The porous surface of acrylic orthodontic removable appliances creates a niche for microbial plaque accumulation, and changes the oral flora by raising cariogenic bacteria including Streptococcus mutans. In this study, we evaluated the mechanical properties and antimicrobial activities of incorporating different concentrations of Curcumin-Nisin-poly(l-lactic acid) nanoparticle (CurNisNps) into orthodontic acrylic resin against Streptococcus mutans and Candida albicans. Methods Following synthesis and characterization of CurNisNps, acrylic resin specimens with different concentrations of CurNisNps (0, 1, 2, 5, and 10 w/w) were fabricated. Flexural strength values, antimicrobial effects, anti-biofilm potential, and anti-metabolic activity against S. mutans and C. albicans were assessed at different time intervals. Also, the expression of the virulence-factor-related genes of S. mutans and C. albicans was assessed by quantitative real-time polymerase chain reaction following treatment with CurNisNps. Results Acrylic resin containing 10 CurNisNps (30.76 +/- 3.91 MPa) showed flexural failure in comparison with acrylic resin specimens without CurNisNps (50.67 +/- 1.82 MPa) as the control group (P 0.05). Acrylic resin with 5 CurNisNps showed the highest concentration of CurNisNps and clinically accepted flexural strength value (14.89 +/- 3.26 MPa, P < 0.05) simultaneously. In the disc agar diffusion assay, 5 CurNisNps showed a high level of inhibitory activity for the test microorganisms. The reduction of growth inhibition zones of the different concentrations of CurNisNps against test microorganisms was positively associated with the time, in such a way that it was reduced significantly after 60 days. The anti-biofilm and anti-metabolic activities of acrylic resin specimens containing a 5 concentration of CurNisNps against S. mutans and C. albicans could significantly decrease the expression levels of gtfB (6.8-fold) and HWP (3.4-fold) in S. mutans and C. albicans, respectively. Conclusions Our data support that 5 (w/w) of CurNisNps can serve as an excellent orthodontic acrylic resin additive against S. mutans and C. albicans biofilm without adverse effects on its mechanical property

Streptococcus mutans bystander-induced bioeffects following sonodynamic antimicrobial chemotherapy through sonocatalytic performance of Curcumin-Poly (Lactic-co-Glycolic Acid) on off-target cells

To assessed the Streptococcus mutans bystander-induced bioeffects following sonodynamic antimicrobial chemotherapy (SACT) by Curcumin-Poly (Lactic-co-Glycolic Acid) nanoparticles (Cur-PLGA-NPs). Cur-PLGA-NPs were synthesized and characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), and Attenuated Total Reflection Fourier Transform IR (ATR-FTIR) spectroscopy, as well as, determination of in vitro drug release. Following the successful synthesis and characterization of Cur-PLGA-NPs, the cell survival, intracellular ROS production, apoptotic effects, DNA fragmentation, and gene expression levels of pro-inflammatory cytokines were investigated on human gingival fibroblast (HGF) cells as off-target cells through S. mutans bystander-induced bioeffects following SACT (BCSS). No significant cytotoxic and damage caused by the release of ROS from BCSS were observed in HGF cells (P &gt; 0.05). There was no DNA fragmentation and anti-proliferation effects on HGF cells. The expression levels of bFGF, TNF-α, and IL-8 genes were increased after exposure to BCSS to 15.4-, 13.5-, and 8.7-fold, respectively (P &lt; 0.05), while TGF-� and IL-10 were downregulated to -4.1- and -6.8-fold, respectively (P &lt; 0.05). It could be concluded that there were no bystander bioeffects of targeted sonocatalytic stress on off-target cells. © 2020 Elsevier B.V

Modulation of the triggered apoptosis by nano emodin transfersome-mediated sonodynamic therapy on head and neck squamous cell carcinoma cell lines

Background: Non-invasive sonodynamic therapy (SDT) is a new treatment modality that uses low-intensity ultrasound to activate a non-toxic sensitizing chemical agent for cancer therapy in a site-directed manner. This study aimed to investigate the anti-cancer effects of ultrasound combined with nano emodin transfersome (NET) on head and neck squamous cell carcinoma (HNSCC) cell lines. Materials and methods: A transfersome form of nano emodin as a novel sono-responsive nanomaterial was synthesized to enhance the accumulation and penetration of nanoparticles. iIn vitro experiments including hemolytic activity, cell proliferation, intracellular reactive oxygen species (ROS) generation, apoptosis induction, DNA fragmentation, and mRNA expressions of caspase 3 and 9 were conducted to explore the anti-cancer effects of NET-SDT on FaDu and CAL-27 cell lines. Results: Characterization tests showed the round and uniform morphology of NET with transfersome structure, resulting in a high drug-loading content and encapsulation ef�ciency. No significant hemolytic activity was observed (P &gt; 0.05). Cytotoxicity gradually increased with increasing concentrations of NET, so that 10 � 10�4 g/L of NET plus 5 min ultrasound irradiation at a frequency of 1 MHz and ultrasonic intensity of 2 W/cm2 effectively killed 98.2 and 97.3 of FaDu and CAL-27 cell lines, respectively (P &lt; 0.05). We found that ROS generation in NET-SDT was dose-dependent and the triggered apoptosis and caspase-3/9 gene expression levels were significantly enhanced as the concentration of NET increased (P &lt; 0.05). No significant difference was found in the rate of apoptosis induction and gene expression between two cell lines. Conclusions: Our data demonstrated that SDT with NET as a sonosensitizer can induce apoptosis and significantly decrease cell viability of HNSCC cell lines, which represents the role of NET-SDT as a potent anti-cancer modality. © 2021 Elsevier B.V

The anti-biofilm capability of nano-emodin-mediated sonodynamic therapy on multi-species biofilms produced by burn wound bacterial strains

Background: Management of burn wound infections (BWIs) is difficult due to the emergence of multidrug-resistant microorganisms. This study aimed to explore the anti-biofilm efficacy of sonodynamic therapy (SDT) using nano-emodin (N-EMO) against multi-species bacterial biofilms containing Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. Methods: Following synthesis and confirmation of N-EMO as a sonosensitizer, the anti-biofilm efficacy of SDT against multi-species bacterial biofilms was determined using minimum inhibitory concentrations (MIC), minimum biofilm inhibitory concentration (MBIC), and minimal biofilm eradication concentration (MBEC) of N-EMO. The reduction of multi-species bacterial biofilms was then evaluated following the treatments using Log reduction and crystal violet (CV) assays. In addition, the expression profiling of abaI, agrA, and lasI genes using SDT with sub-MIC, sub-MBIC, and sub-MBEC of N-EMO was assessed. Results: Successful synthesis of N-EMO was confirmed through several characterization tests. As the results demonstrated, the MIC value of N-EMO for the multi-species bacterial suspension was 0.15 � 10�4 g/L, as well as, the MBEC value of N-EMO was 2.5 � 10�4 g/L, approximately 4-fold higher than that of MBIC (0.62 � 10�4 g/L). According to the CV assay, there were 57.8 , 71.0 , and 81.5 reduction in the biofilm of multi-species bacterial growth following SDT using 1/128 MBEC, 1/16 MBIC, and 1/2 MIC of N-EMO, respectively. Log reductions analysis demonstrated that 1/2 MIC of N-EMO was more potent in inhibiting the biofilm growth of multi-species test bacteria by 5.725 ± 0.12 (99.9993 ). In this study, N-EMO-mediated SDT could obviously downregulate the gene expression of virulence factors (P &lt; 0.05). The gene expression of lasI, agrA, and abaI were downregulated about 2.5-, 3.6-, and 5.5-fold; and 3.0-, 5.2-, and 7.4-fold following SDT with sub-MBIC and sub-MBEC of N-EMO, respectively. Conclusion: These results highlight the potential of N-EMO-mediated SDT in inhibition of biofilm formation, degradation of formed biofilms, and reduction of virulence factor associated with biofilms of multi-species bacterial biofilms in BWIs. © 2021 Elsevier B.V

In vitro antibacterial activity and durability of a nano-curcumin-containing pulp capping agent combined with antimicrobial photodynamic therapy

Background: Considering the antibacterial properties of nano-curcumin (nCur) reinforced with antimicrobial photodynamic therapy (aPDT), this study aimed to assess the antibacterial activity and durability of Activa BioActive Base/Liner (ABBL) containing nCur (nCur-ABBL) as a pulp capping agent against Streptococcus mutans, the most common cause of secondary caries. Materials and methods: In this in vitro experimental study, ABBL discs containing 0.5 , 1, 2, and 5 (w/w) concentrations of nCur were fabricated. After aPDT using light emitting diode (LED) at 435 ± 20 nm wavelength for 5 min, the discs were undergone aging in artificial saliva for 90 days. The antibacterial activity of the discs against S. mutans was evaluated by the disc agar diffusion test, and the number of bacterial colonies present in the biofilm formed on the disc surfaces was counted after 0, 15, 30, and 60 days of aging. Results: The maximum growth inhibition zone was noted around the 5 nCur-ABBL discs. Increasing the concentration of nCur from 0.5 to 5 combined with aPDT significantly decreased the number of S. mutans colonies in the biofilm over time (P 0.05). Conclusion: According to our data, 5 nCur-ABBL revealed the largest growth inhibition zone in S. mutans culture. Moreover, 5 nCur can serve as an excellent ABBL additive in aPDT producer against S. mutans biofilms up to 60 days of aging period. © 2020 Elsevier B.V