Anti-inflammatory effect of photodynamic therapy using guaiazulene and red lasers on peripheral blood mononuclear cells

Effectiveness of photodynamic therapy on the treatment of chronic periodontitis: a systematic review during 2008-2023

Objective

This study investigated the effect of photodynamic therapy on chronic periodontitis patients and then evaluated the microbial, immunological, periodontal, and clinical outcomes. The significant effects of photodynamic therapy obtained by in vitro and in vivo studies have made it a popular treatment for periodontal diseases in recent years. Photodynamic therapy is a novel bactericidal strategy that is stronger, faster, and less expensive than scaling and root planing.

Method

This study registered on PROSPERO (CRD42021267008) and retrieved fifty-three randomized controlled trials by searching nine databases (Medline, Embase, Scopus, Open Gray, Google Scholar, ProQuest, the Cochrane Library, Web of Science, and ClinicalTrials.gov) from 2008 to 2023. Of 721 records identified through database searches following title and full-text analysis, and excluding duplicate and irrelevant publications, 53 articles were included in this systematic review. Fifty of the 53 eligible studies fulfilled all the criteria in the Joanna Briggs Institute's (JBI's) Checklist for RCTs; the remaining articles met 9-12 criteria and were considered high quality.

Results

The present study showed that photodynamic therapy in adjunct to scaling and root planing has the potential to improve periodontal parameters such as clinical attachment loss or gain, decrease in bleeding on probing, and probing pocket depth. In addition, photodynamic therapy decreases the rate of periodontal pathogens and inflammation markers, which, in turn, reduces the progression of periodontitis.

Conclusion

Photodynamic therapy is considered a promising, adjunctive, and low-cost therapeutic method that is effective in tissue repair, reducing chronic periodontitis, reducing inflammation, and well-tolerated by patients.

Azulene and Its Derivatives as Potential Compounds in the Therapy of Dermatological and Anticancer Diseases: New Perspectives against the Backdrop of Current Research

The scientific article focuses on the role of azulene and its derivatives in the therapy of dermatological diseases, presenting the latest laboratory and clinical research as well as prospects for further studies. In a synthetic literature review, various databases such as PubMed, Scopus, Web of Science, and the Database of Polish Scientific Journals were queried to select relevant articles concerning azulene. The conclusions drawn from the thematic analysis of the studies emphasize the multifaceted pharmacological actions of azulene and its derivatives including their anti-inflammatory properties, potential anticancer effects, photoprotective abilities, alleviation of itching, management of atopic dermatitis, and treatment of erectile dysfunction. However, there are certain limitations associated with the application of unmodified azulene on the skin, particularly related to photodecomposition and the generation of reactive oxygen species under UV radiation. These effects, in turn, necessitate further research on the safety of azulene and azulene-derived substances, especially regarding their long-term use and potential application in phototherapy. The authors of this work emphasize the necessity of conducting further preclinical and clinical studies to fully understand the mechanisms of action. Incorporating azulene and its derivatives into the therapy of dermatological disorders may represent an innovative approach, thereby opening new treatment avenues for patients.

Photodynamic anti-inflammatory activity of meso‑aryl substituted porphyrin derivative on mammalian macrophages

BACKGROUND

Our group focused on a meso‑aryl substituted porphyrin molecule for its photodynamic anti-inflammatory activities on the mammalian macrophages.

MATERIALS AND METHODS

The porphyrine derivative previously synthesized in this study was synthesized and characterized by 1H NMR. We then examined their immunomodulatory activities based on the changes in the pro-inflammatory cytokine production levels after LPS stimulation in dark and light activated conditions.

RESULTS

Our results suggest that porphyrin derivative had anti-inflammatory photodynamic activity in vitro at subtoxic concentrations. Our study aims to pave a way for anti-inflammatory photodynamic therapy application in the inflammatory and autoimmune disorders. Most of the studies either focus on photodynamic cytotoxicity of the porphyrin derivatives to suppress the inflammation or porphyrin derivatives' anti-inflammatory activity without the photodynamic activation.

CONCLUSION

Our future studies will focus on the generation and in vitro as well as in vivo characterization of the porphyrin derivatives with anti-inflammatory photodynamic therapy applications. In this way, novel drug candidates that would have lower side effects can be generated for the patients.

Novel Synthesized Tyrosinase Inhibitors: A Systematic Patent Review (2012-Present)

Tyrosine is an enzyme responsible for melanin production. Its abnormal accumulation in different parts of the body is known as hyperpigmentation. Tyrosinase inhibitors have been used as one of the main approaches to treat these kinds of cosmetic and medical issues. This review aimed to discuss the advances in patents for this class of inhibitors, focusing on synthetic ones, by studying recent patent applications (2012-2022). We performed a screening using the European Patent Office's Espacenet database, from which 15 inventions were selected and fully studied. China has more patent applications, all of them were focused on synthetic methods and the majority declared at least two additional applications as antibrowning agents for fruits and vegetables, biological pesticides, and medicine to treat diseases like Parkinson's or melanoma. The strategies employed by the investigators focused on the examination of previous literature, which oriented on the type of structures that have been found to show good inhibitory activity; the study also examined aspects of their reaction mechanisms and information about the structureactivity relationship. For some groups of inhibitors, such as benzaldehyde and anthraquinone derivatives, the data were meaningful and extensive. In contrast, arginyl and troponoids compounds were difficult to analyze due to the limited research works.

Guaiazulene and related compounds: A review of current perspective on biomedical applications

BACKGROUND

Thousands of people worldwide pass away yearly due to neurological disorders, cardiovascular illnesses, cancer, metabolic disorders, and microbial infections. Additionally, a sizable population has also been impacted by hepatotoxicity, ulcers, gastroesophageal reflux disease, and breast fissure. These ailments are likewise steadily increasing along with the increase in life expectancy. Finding innovative therapies to cure and consequently lessen the impact of these ailments is, therefore, a global concern.

METHODS AND MATERIALS

All provided literature on Guaiazulene (GA) and its related compounds were searched using various electronic databases such as PubMed, Google Scholar, Web of Science, Elsevier, Springer, ACS, CNKI, and books via the keywords Guaiazulene, Matricaria chamomilla, GA-related compounds, and Guaiazulene analogous.

RESULTS

The FDA has approved the bicyclic sesquiterpene GA, commonly referred to as azulon or 1,4-dimethyl-7-isopropylazulene, as a component in cosmetic colorants. The pleiotropic health advantages of GA and related substances, especially their antioxidant and anti-inflammatory effects, attracted a lot of research. Numerous studies have found that GA can help to manage various conditions, including bacterial infections, tumors, immunomodulation, expectorants, diuretics, diaphoresis, ulcers, dermatitis, proliferation, and gastritis. These conditions all involve lipid peroxidation and inflammatory response. In this review, we have covered the biomedical applications of GA. Moreover, we also emphasize the therapeutic potential of guaiazulene derivatives in pre-clinical and clinical settings, along with their underlying mechanism(s).

CONCLUSION

GA and its related compounds exhibit therapeutic potential in several diseases. Still, it is necessary to investigate their potential in animal models for various other ailments and establish their safety profile. They might be a good candidate to advance to clinical trials.

Short-term influence of antimicrobial photodynamic therapy as an adjuvant to mechanical debridement in reducing soft-tissue inflammation and subgingival yeasts colonization in patients with peri-implant mucositis

OBJECTIVE

The objective of this short-term follow-up study was to evaluate the influence of antimicrobial photodynamic therapy (aPDT) as an adjuvant to mechanical debridement (MD) in reducing soft-tissue inflammation and subgingival yeasts colonization (SYC) in patients with peri‑implant mucositis (PiM).

METHODS

Individuals diagnosed with PiM were included. Demographic data was collected using a questionnaire. Peri-implant plaque index (PI), bleeding index (BI), probing depth (PD), crestal bone levels and SYC were measured at baseline. Therapeutically, these individuals were divided into test and control groups. In the control-group patients underwent MD and in the test-group patients underwent MD with adjunct single session of aPDT. Clinical peri‑implant parameters and SYC were reassessed after 12-weeks. Correlation between age, gender and duration of implants with SYC and clinical peri‑implant status was assessed using logistic regression models. P < 0.05 was selected as an indicator of statistical significance.

RESULTS

The test and control-groups comprised of 24 and 23 individuals, respectively. In the test and control groups, toothbrushing twice daily was reported by 7 (29.2%) and 5 (21.7%) individuals, respectively. None of the individuals had ever used a dental floss. At baseline, there was no difference in peri‑implant PI, BI, PD and CBL in the test and control groups. At follow-up, peri‑implant PI (P < 0.01), BI (P < 0.01) and PD (P < 0.01) were significantly higher in the control compared with the test-group. At baseline, SYC in the test and control groups were 1865.3 ± 403.4 CFU/ml and 1963.7 ± 512.4 CFU/ml, respectively. At 90 days' follow-up, SYC in the test and control groups were 1472 ± 202.7 and 1538.4 ± 331.7 CFU/ml, respectively. There was no significant difference in SYC in both groups when baseline values were compared with 90 days' follow-up.

CONCLUSION

One session of aPDT after MC with adjunct aPDT is effective in reducing soft tissue inflammation but not SYC in patients with PiM.

Anti-biofilm and bystander effects of antimicrobial photo-sonodynamic therapy against polymicrobial periopathogenic biofilms formed on coated orthodontic mini-screws with zinc oxide nanoparticles

BACKGROUND

The present study evaluated the anti-biofilm and bystander effects of antimicrobial photo-sonodynamic therapy (aPSDT) on the polymicrobial periopathogenic biofilms formed on mini-screws coated with zinc oxide nanoparticles (ZnONPs).

MATERIALS AND METHODS

Thirty orthodontic identical mini-screws were divided into 6 groups (n = 5) as follows: 1. negative control: uncoated mini-screw + phosphate-buffered saline (PBS), 2. positive control: uncoated mini-screw + 0.2% CHX, 3. coating control: coated mini-screw + PBS, 4. antimicrobial photodynamic therapy (aPDT): coated mini-screw+light emitting diode (LED), 5. Antimicrobial sonodynamic therapy (aSDT): coated mini-screw+ultrasound waves, and 6. aPSDT: coated mini-screw+LED+ultrasound waves. Electrostatic spray-assisted vapor deposition was employed to coat ZnONPs on titanium mini-screws. The biofilm inhibition test was used to assess the anti-biofilm efficacy against polymicrobial periopathogenic biofilms including Porphyromonas gingivitis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans, and the results were shown as the percent reduction of Log₁₀ colony-forming unit (CFU)/mL. Following each treatment, the gene expression levels of TNF-α, IL-1β, and IL-6 were evaluated on human gingival fibroblast (HGF) cells via quantitative real-time polymerase chain reaction (qRT-PCR) to reveal the bystander effects of aPSDT on HGF cells.

RESULTS

A significant reduction in log₁₀ CFU/mL of periopathogens was observed in groups treated with aPDT, aSDT, aPSDT, and 0.2% CHX up to 6.81, 6.63, 5.02, and 4.83 log, respectively, when compared with control groups (P<0.05). 0.2% CHX and aPSDT groups demonstrated significantly higher capacity in eliminating the periopathogen biofilm compared with other groups (P<0.05). The qRT-PCR showed that the expression level of inflammatory cytokines was significantly down regulated in aPDT, aSDT, and aPSDT groups (P<0.05).

CONCLUSION

It was found that the ZnONPs-mediated aPSDT could significantly reduce periopathogen biofilm as well as the expression level of inflammatory cytokines.

Optical spectral diagnostics of the oxygenation level in periodontal tissues and photodynamic therapy using methylene blue in children with cerebral palsy

Dental diseases occur in children with cerebral palsy three times higher than in healthy children. Low values of the unstimulated salivation rate (<0.3 ml per minute), pH and buffer capacity, changes in enzyme activity and sialic acid concentration, as well as increased saliva osmolarity and total protein concentration, which indicates impaired hydration, are the factors in the development of a gingiva disease in case of cerebral palsy. This leads to increased bacterial agglutination and the formation of acquired pellicle and biofilm, leading to the formation of dental plaque. There is a tendency toward an increase in the concentration of hemoglobin and a decrease in the degree of hemoglobin oxygenation, as well as an increase in the generation of reactive oxygen and nitrogen species. Photodynamic therapy (PDT) with the use of photosensitizer methylene blue improves blood circulation and the degree of oxygenation in periodontal tissues, as well as eliminates a bacterial biofilm. Analysis of back diffuse reflection spectra makes it possible to conduct non-invasive monitoring determine tissue areas with a low level of hemoglobin oxygenation for precision photodynamic exposure.

Aim

To improve the effectiveness of phototheranostics methods using, namely PDT with simultaneous optical-spectral control, for the treatment of gingivitis in children with complex dental and somatic status (cerebral palsy).

Methods

The study involved 15 children (6-18 y.o.) with various forms of cerebral palsy, in particular, spastic diplegia and atonic-astatic form and with gingivitis. The degree of hemoglobin oxygenation was measured in tissues before PDT and on the 12th day. PDT was performed using laser radiation (λ = 660 nm) with a power density of 150 mW/cm² with a five-minute application of 0.01% MB. The total light dose was 45 ± 15 J/cm². For statistical evaluation of the results, a paired Student's t-test was used.

Results

The paper presents the results of phototheranostics using methylene blue in children with cerebral palsy. An increase in the level of hemoglobin oxygenation from 50 to 67% (p < 0.001) and a decrease in blood volume in the microcirculatory bed of periodontal tissues were shown.

Conclusion

Photodynamic therapy methods with application of methylene blue make it possible to assess the state of the gingival mucosa tissue diseases objectively in real time, and to provide effective targeted therapy for gingivitis in children with cerebral palsy. There is a prospect that they can become widely used clinical methods.

Azulene-Containing Squaraines for Photoacoustic Imaging and Photothermal Therapy

Photoacoustic imaging (PAI) guided photothermal therapy (PTT) can realize real-time diagnosis and in situ treatment of cancer at the same time. Absorption in the near-infrared (NIR) region with large molar extinction coefficient (ε) and high value of photothermal conversion efficiency (PCE) are key prerequisites for photothermal agents (PTAs) to realize dual PAI and PTT treatments. Squaraines have stable quinoid structures with strong planarity and rigidity, in favor of the NIR absorption and high ε values. On the other hand, azulene derivatives mostly have very faint fluorescence emission, which is beneficial for photothermal transformation. Herein, two azulene-containing squaraines Az-SQ-1 and Az-SQ-2 are synthesized as high-performance PTAs. In comparison with Az-SQ-1, Az-SQ-2 possesses larger ε_max of 3 × 10⁵ M^-1 cm^-1 at 780 nm in organic solution and higher PCE of 53.2% in the form of nanoparticles under 808 nm laser irradiation. Accordingly, Az-SQ-2 NPs present stronger photoacoustic signals (about 15.1-times the background signal) and more efficient suppression of tumor growth. Our research indicates that the introduction of azulene unit to traditional NIR dyes is a simple but effective approach to obtain outstanding PTAs in the aspect of phototheranostics.

Tumor-Specificity, Neurotoxicity, and Possible Involvement of the Nuclear Receptor Response Pathway of 4,6,8-Trimethyl Azulene Amide Derivatives

Background: Very few papers covering the anticancer activity of azulenes have been reported, as compared with those of antibacterial and anti-inflammatory activity. This led us to investigate the antitumor potential of fifteen 4,6,8-trimethyl azulene amide derivatives against oral malignant cells. Methods: 4,6,8-Trimethyl azulene amide derivatives were newly synthesized. Anticancer activity was evaluated by tumor-specificity against four human oral squamous cell carcinoma (OSCC) cell lines over three normal oral cells. Neurotoxicity was evaluated by cytotoxicity against three neuronal cell lines over normal oral cells. Apoptosis induction was evaluated by Western blot and cell cycle analyses. Results: Among fifteen derivatives, compounds 7, 9, and 15 showed the highest anticancer activity, and relatively lower neurotoxicity than doxorubicin, 5-fluorouracil (5-FU), and melphalan. They induced the accumulation of a comparable amount of a subG₁ population, but slightly lower extent of caspase activation, as compared with actinomycin D, used as an apoptosis inducer. The quantitative structure–activity relationship analysis suggests the significant correlation of tumor-specificity with a 3D shape of molecules, and possible involvement of inflammation and hormone receptor response pathways. Conclusions: Compounds 7 and 15 can be potential candidates of a lead compound for developing novel anticancer drugs.

Guaiazulene derivative 1,2,3,4-tetrahydroazuleno[1,2-b] tropone reduces the production of ATP by inhibiting electron transfer complex II

Molecularly targeted therapy has been used for treatment of various types of cancer. However, cancer cells often acquire resistance to molecularly targeted drugs that inhibit specific molecular abnormalities, such as constitutive activation of kinases. Even in cancer cells that have acquired resistance, enhanced anabolism, including the synthesis of nucleotides, amino acids and lipids, is common to normal cancer cells. Therefore, there is a renewed interest in effectively eliminating cancer cells by specifically targeting their abnormal energy metabolism. Multiple strategies are currently being developed for mitochondrial-targeted cancer therapy, with agents targeting oxidative phosphorylation, glycolysis, the tricarboxylic acid cycle and apoptosis. In this study, we found that one of the guaiazulene derivatives, namely, 1,2,3,4-tetrahydroazuleno[1,2-b] tropone (TAT), inhibited the proliferation of cancer cell lines stronger than that of normal cells. In addition, we showed that TAT inhibited energy production in cancer cell lines, resulting in apoptosis. Analyses done in cancer cell lines and in the animal model Caenorhabditis elegans suggested that TAT acts on the mitochondrial electron transfer complex II and suppresses cellular energy production by inhibiting oxidative phosphorylation across species. These results suggest that TAT could represent a novel anticancer agent that selectively targets mitochondria.

In vitro and in vivo biological activities of azulene derivatives with potential applications in medicine

Azulene is an aromatic hydrocarbon that possesses a unique chemical structure and interesting biological properties. Azulene derivatives, including guaiazulene or chamazulene, occur in nature as components of many plants and mushrooms, such as Matricaria chamomilla, Artemisia absinthium, Achillea millefolium, and Lactarius indigo. Due to physicochemical properties, azulene and its derivatives have found many potential applications in technology, especially in optoelectronic devices. In medicine, the ingredients of these plants have been widely used for hundreds of years in antiallergic, antibacterial, and anti-inflammatory therapies. Herein, the applications of azulene, its derivatives and their conjugates with biologically active compounds are presented. The potential use of these compounds concerns various areas of medicine, including anti-inflammatory with peptic ulcers, antineoplastic with leukemia, antidiabetes, antiretroviral with HIV-1, antimicrobial, including antimicrobial photodynamic therapy, and antifungal.