Effect Of ALA-PDT Research Articles

Combinatory effect of ALA-PDT and itraconazole in the treatment of cutaneous protothecosis

BackgroundAs a rare subcutaneous infection, protothecosis is easily misdiagnosed. Similar to other subcutaneous infection, there is no unified standard for treatment, for cases not suitable for surgery, clinicians often use antifungal drugs based on their experience, and the course of treatment varies from several months to several years. Based on the fact that there are few relevant materials and researches on photodynamic therapy (PDT), we conducted a study based on a clinical case that used oral itraconazole combined with 5-aminolevylinic acid photodynamic therapy (ALA-PDT) to treat a patient with cutaneous protothecosis caused by Prototheca wicherhamii. MethodsDifferent concentrations of ALA and different light doses were used to investigate the effects of ALA-PDT on the growth inhibition of P. wickerhamii in vitro with Colony-counting Methods. And we used transmission electron microscopy (TEM) to visualize the structural changes and the effects of ALA-PDT treating on cellular structures of the P. wickerhamii. Futher, we performed the susceptibility test of P. wickerhamii to itraconazole before and after ALA-PDT in vitro. ResultsWe have successfully treated a patient with cutaneous protothecosis caused by P. wickerhamii by using combination therapy in a total of 9-week course of treatment. In vitro, ALA-PDT can inhibit the growth of P. wickerhamii when the ALA concentration was 5 mg/mL (P < 0.01), and this effect became stronger as the concentration of ALA or light dose is increased. Using TEM, we confirmed that ALA-PDT can disrupt the cell wall structure and partition structure of P. wickerhamii, which may contribute to its inhibitory effect. Further studies showed that the MIC of itraconazole for P. wickerhamii was decreased after ALA-PDT. ConclusionsALA-PDT combined with oral itraconazole can be used to treat cutaneous protothecosis. Accordingly, ALA-PDT can destroy the cell wall and partition structure of P. wickerhamii leading to an inhibitory effect on it in vitro, and the effect is enhanced with the increase of ALA concentration and light dose. Also, the sensitivity of P. wickerhamii to itraconazole is observed increased after ALA-PDT. So our study provides a theoretical basis for the promising treatment against cutaneus protothecosis.

5-Aminolevulinic acid photodynamic therapy is a safe and effective treatment for female patients with intractable vulvar lichen sclerosus

BackgroundFemale vulvar lichen sclerosus (VLS) is a chronic inflammatory skin disease of the vulva and its etiology is unknown. The main clinical symptoms are itching, burning and dyspareunia, and there is a lack of effective treatment. MethodsClinical and follow-up data of women with VLS who underwent 5-Aminolevulinic acid photodynamic therapy (ALA-PDT) from January 2023 to December 2023 in the department of obstetrics and gynecology, Qilu Hospital of Shandong University, were retrospectively analyzed. According to the inclusion and exclusion criteria, 36 patients with VLS who received ineffective conventional treatment (intractable VLS) were enrolled. Objective signs and subjective symptoms of vulvar lesions were recorded before treatment and 6 months after the end of treatment according to corresponding scoring criteria. Quality of life was evaluated using the Dermatology Life Quality Index (DLQI). ResultsAll patients received six sessions of ALA-PDT treatment and follow-up visits. After ALA-PDT treatment, 24 of 36 (66.67 %) patients' itching symptoms completely disappeared, 10 of 36 (27.78 %) patients' itching symptoms were relieved from severe to mild, and only 2 of 36 (5.56 %) patients' symptoms were not significantly relieved. 16 of 36 (44.4 %) patients' itching symptoms completely disappeared, 9 of 36 (25 %) patients' itching symptoms were relieved from severe to mild, and only 2 of 36 (5.56 %) patients still had severe pain. Compared to 22 patients with dyspareunia before treatment, only 9 patients still had dyspareunia with varying degrees of dyspareunia relief after treatment. Clinical signs improved significantly in the patients after ALA-PDT treatment. The total scores of clinical signs were (5.31 ± 1.67 vs 3.67 ± 1.71) before and after treatment. All patients showed improvement in DLQI after treatment. The main side effects of ALA-PDT were pain, erythema and swelling which were transient and tolerable. All patients were “satisfied” or “very satisfied” with the results of the treatment. ConclusionsALA-PDT is a safe and effective treatment for women with intractable vulva lichen sclerosus.

5-aminolevulinic acid photodynamic therapy inhibits the viability, invasion, and migration of cervical cancer SiHa cells by regulating the miR-152-3p/JAK1/STAT1 axis

BackgroundCervical cancer ranks the fourth most prevalent type of cancer worldwide, characterized by a notably low survival rate, particularly in its metastatic stage. Despite 5-aminolevulinic acid photodynamic therapy (ALA-PDT) demonstrating potential anti-tumor effects against cervical cancer, the intricate mechanisms underlying its efficacy necessitate further investigation. Here, the study aims to elucidate the impact of ALA-PDT on the cancer cell viability, invasion and migration, alongside delineating the underlying molecular mechanisms. MethodsCervical cancer SiHa cells were subjected to ALA and red light irradiation, and we then measured the ALA-PDT's effects on cell functions using various assays. The potential interaction between miR-152–3p and JAK1 was explored through bioinformatics analyses and validated by dual-luciferase reporter assays. Post-transfection with miR-152–3p and JAK1 vectors, cellular functions were re-evaluated. The efficacy of ALA-PDT in tumor suppression was further investigated through tumor transplantation experiment in vivo. ResultsALA-PDT markedly suppressed SiHa cell viability, invasion and migration, impacting critical markers of proliferation, apoptosis, and epithelial-mesenchymal transition(EMT). And these effects were echoed by the inhibition of miR-152–3p. JAK1 was identified as a direct target of miR-152–3p, and ALA-PDT was found to regulate the expression levels of miR-152–3p, consequently influencing the JAK1/STAT1 signaling pathway. Augmentation of miR-152–3p expression and inhibition of the JAK1/STAT1 pathway mitigated the anti-cancer effects of ALA-PDT, whereas JAK1 overexpression diminished these effects. In vivo analyses demonstrated that ALA-PDT suppressed tumor growth and modulated the miR-152–3p/JAK1/STAT1 pathway expression. ConclusionsALA-PDT inhibits the viability, invasion, and migration of cervical cancer SiHa cells by modulating the miR-152–3p/JAK1/STAT1 axis, offering a promising therapeutic avenue for combating invasive cervical cancer.

Photodynamic therapy of esophageal precancerous and cancer diseases

SignificanceThe aim of the study was to present the results and own experience in the treatment of esophagus precancer and cancer diseases using ALA PDT. ApproachThe analysis covered 23 patients treated in 2006-2020 at our Center for Diagnostics and Laser Therapy. 5-ALA was given orally in the dose of 60 mg/kg body weight and irritated using DIOMED laser light (630 nm) delivered via a cylindrical diffuser 4–6 h after the first dose of PSs. ResultsThe median survival rate was 30.9 months if PDT was the initial treatment and 14.3 months if other methods were used first. The serious side effects of PDT were no observed. ConclusionsOur research results indicate the beneficial effects of ALA PDT in the treatment of esophageal diseases, especially in Barratt's esophagus, however, the use of this method in the treatment of esophageal cancer, also finds its place.

ALA-PDT promotes the death and contractile capacity of hypertrophic scar fibroblasts through inhibiting the TGF-β1/Smad2/3/4 signaling pathway

BackgroundHypertrophic scars, an abnormal wound-healing response to burn injuries, are characterized by massive fibroblast proliferation and excessive deposition of extracellular matrix and collagen. 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) is a promising therapy for hypertrophic scar, details of the mechanisms remain to be elucidated. In this study, we aimed to investigate the molecular mechanisms involved in ALA-PDT against hypertrophic scar fibroblasts. MethodsThe morphologies of hypertrophic scar fibroblasts (HSFs) treated with ALA-PDT were observed under a light microscopy. The viability of HSFs was detected using the CCK-8 assay. HSFs-populated collagen gel contraction assays were conducted to examine the fibroblast contractility and the cytotoxicity of HSFs in 3D collagen tissues were observed using confocal microscopy. The effect of ALA-PDT on TGF-β1/Smad2/3/4 signaling pathway activation and effector gene expression were verified by immunoprecipitation, western blot and real-time quantitative PCR analysis. ResultsWe observed significant changes in cell morphology after ALA-PDT treatment of HSFs. As ALA concentration and light dose increased, the viability of HSFs significantly decreased. ALA-PDT can significantly alleviate the contractile capacity and promote the death of HSFs induced by TGF-β1 treatment in a three-dimensional collagen culture model. TGF-β1 treatment of HSFs can significantly induce phosphorylation of Smad2/3 (p-Smad2/3) in whole cells, as well as p-Smad2/3 and Smad4 proteins into the nucleus and increase the mRNA levels of collagen 1/3 and α-SMA. ALA-PDT hampers the TGF-β1-Smad2/3/4 signaling pathway activation by inducing K48-linked ubiquitination and degradation of Smad4. ConclusionsOur results provide evidence that ALA-PDT can inhibit fibroblast contraction and promote cell death by inhibiting the activation of the TGF-β1 signaling pathway that mediates hypertrophic scar formation, which may be the basis for the efficacy of ALA-PDT in the treatment of hypertrophic scars.

Analysis of the effectiveness of PDT with 5-aminolevulinic acid in comparison to blue/red light combined with intralesional triamcinolone injection in treatment of severe inflammatory acne: A retrospective study.

In this study, the therapeutic effect of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in comparison to blue/red light combined with intralesional triamcinolone injection for severe inflammatory acne was evaluated and analyzed. One hundred and four cases of severe inflammatory acne were analyzed in this study. They were divided into two groups as control and observation groups, 52 cases in each group. The control group (group A) received red and blue light combined with triamcinolone injection and lidocaine injection (1:4), while the observation group (Group B) was treated with ALA-PDT. Finally, the therapeutic effect and the occurrence of adverse reactions were compared between the two groups. After 2, 4 and 6 weeks, the effectiveness rates of group B was 28.85%, 75.00%, and 86.54%, respectively while it was 9.62%, 51.92%, and 69.23%, respectively in group A. The difference between A and B was statistically remarkable (χ2 = 6.1905, 5.9713, 4.5217, p = 0.0128, 0.0145, 0.0335 at p < 0.05). In addition, the incidence of adverse reactions in B was 5.77%, lower than A (32.69%). This difference between A and B was statistically remarkable (χ2 = 12.1333, p = 0.0005). After 2, 4, and 6 weeks of treatment, the number of residual lesions in the group B group was remarkably lower than group A (p < 0.01). There was remarkable difference in the incidence of pain, burning sensation, pigmentation and erythema between the two groups. The therapeutic effect of ALA-PDT in the treatment of severe acne is better than red blue light combined with triamcinolone injection and lidocaine injection. In addition, ALA-PDT has an ideal effect in the treatment of severe acne.

Effect of 5-Aminolevulinic Acid Photodynamic Therapy on Aspergillus fumigatus Biofilms in Vitro

Aspergillus fumigatus biofilm development results in enhanced pathogenicity and treatment resistance. Most contemporary antibiotics, however, are unable to eliminate biofilms. In recent years, with the application of new photosensitizers and the development of treatment, ALA-PDT (5-aminolevulinic acid photodynamic treatment) has achieved remarkable curative effect in the treatment of fungal infectious diseases; however, no research has been conducted on ALA-PDT against A. fumigatus. This study investigated the inhibitory effect of ALA-PDT at various 5-aminolevulinic acid concentrations and light doses on A. fumigatus planktonic and biofilms in vitro. We found that ALA-PDT may successfully inhibit the development of A. fumigatus biofilm and disintegrate mature biofilm. After ALA-PDT treatment, the adherence rate and vitality dramatically decreased, and the biofilm’s structure was severely compromised. Our findings show for the first time that ALA-PDT may be used to prevent the formation of A. fumigatus biofilm and disturb the structure of mature biofilm, and that it could be employed as a therapeutic therapy for A. fumigatus superficial infection.

5-Aminolevulinic acid photodynamic therapy versus minocycline for moderate-to-severe rosacea: A single-center, randomized, evaluator-blind controlled study

5-Aminolevulinic acid photodynamic therapy (ALA-PDT) showed potential to treat rosacea according to recent studies, but a lack of clinical evidence and unclear adverse effects limit its use. To compare the effect of ALA-PDT versus minocycline for rosacea. In this single-center, randomized, evaluator-blind, controlled study, patients with moderate to severe rosacea were allocated to receive 3 to 5 sessions of ALA-PDT or 8 weeks of 100 mg daily minocycline treatment, followed by a 24-week follow-up. Of all the 44 randomized patients, 41 received complete treatment (ALA-PDT 20, Minocycline 21). At the end of treatment, ALA-PDT showed non-inferior improvement of papulopustular lesions and Rosacea-related Quality of Life (RosaQoL) compared to minocycline (median reduction of lesion count: 19 vs. 22, median change of RosaQoL score: 0.48 vs. 0.53). The Clinician's Erythema Assessment (CEA) success of ALA-PDT was lower than minocycline's (35% vs. 67%). Demodex density and relapse rate were comparable in both groups. Erythema, mild pain and exudation were the most common adverse reactions of ALA-PDT. Limited sample size restricted us from drawing further conclusions. As minocycline does, ALA-PDT can improve rosacea mainly in papulopustular lesions and patients' quality of life, indicating a new option for rosacea.

Single cell transcriptome profiling reveals cutaneous immune microenvironment remodeling by photodynamic therapy in photoaged skin.

The immune microenvironment plays a critical role in maintaining skin homeostasis, which is closely related to the dysfunction in photoaged skin such as autoimmunity and tumorigenesis. Several recent studies have demonstrated the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in alleviating photoaging and skin cancer. However, the underlying immune mechanisms and the immune microenvironment change by ALA-PDT remain largely unknown. To illustrate the effects of ALA-PDT on immune microenvironment in photoaged skin, single cell RNA sequencing (scRNA-seq) analysis of photoaged skin on the extensor side of the human forearm before and after ALA-PDT was performed. R-packages of Seurat, clusterProfiler, Monocle, CellChat were used for cell clustering, differentially expressed genes analysis, functional annotation, pseudotime analysis and cell-cell communication analysis. The gene sets related to specific functions were extracted from the MSigDB database, which were used to score the functions of immune cells in different states. We also compared our result with published scRNA-seq data of photoaged skin of the eyelids. The increase score of cellular senescence, hypoxia and reactive oxygen species pathway in immune cells and the decrease of immune receptor activity function and proportion of naive T cells were found in skin photoaging. Moreover, the function of T cell ribosomal synthesis was also impaired or down regulated and function of G2M checkpoint was up regulated. However, ALA-PDT showed promising results in reversing these effects, as it improved the above functions of T cells. The ratio of M1/M2 and percentage of Langerhans cells also decreased with photoaging and increased after ALA-PDT. Additionally, ALA-PDT restored the antigen presentation and migration function of dendritic cells and enhanced cell-cell communication among immune cells. These effects were observed to last for 6 months. ALA-PDT has potential to rejuvenate immune cells, partially reversed immunosenescence and improved the immunosuppressive state, ultimately remodelling the immune microenvironment in photoaged skin. These results provide an important immunological basis for further exploring strategies to reverse skin photoaging, chronological aging and potentially systemic aging.

Photodynamic Effects with 5-Aminolevulinic Acid on Cytokines and Exosomes in Human Peripheral Blood Mononuclear Cells from Patients with Crohn's Disease.

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) which is the precursor of the photosensitizer protoporphyrin IX (PpIX) is an available treatment for several diseases. ALA-PDT induces the apoptosis and necrosis of target lesions. We have recently reported the effects of ALA-PDT on cytokines and exosomes of human healthy peripheral blood mononuclear cells (PBMCs). This study has investigated the ALA-PDT-mediated effects on PBMC subsets from patients with active Crohn's disease (CD). No effects on lymphocyte survival after ALA-PDT were observed, although the survival of CD3-/CD19+ B-cells seemed slightly reduced in some samples. Interestingly, ALA-PDT clearly killed monocytes. The subcellular levels of cytokines and exosomes associated with inflammation were widely downregulated, which is consistent with our previous findings in PBMCs from healthy human subjects. These results suggest that ALA-PDT may be a potential treatment candidate for CD and other immune-mediated diseases.

Suppression of resistance to aminolevulinic acid-based photodynamic therapy in esophageal cell lines by administration of iron chelators in collagen type I matrices

Purpose Photodynamic therapy (PDT) utilizes visible light to activate the cytotoxic effects of photosensitizing drugs. PDT protocols require optimization to overcome treatment resistance and induce a beneficial anti-tumor immune response. The aim of this study was to examine the possibility to suppress the resistance of esophageal cell lines to aminolevulinic acid (ALA)-PDT by administration of iron chelators to induce sufficient cell cytotoxicity under pathophysiologically relevant conditions, mimicking the advanced stages of cancer. Materials and methods Effects of ALA-PDT in combination with iron chelators were compared in three esophageal cell lines in conventional monolayers and in 3 D cultures based on collagen type I. Modified colony assay and fluorescence-based live cell imaging, respectively were applied. The latter was used also to test the capability of pre-polarized macrophages to interact with cancer cells subjected to ALA-PDT with or without iron chelators. Results Iron chelators were effective in the enhancement of ALA-PDT in all cell lines under both culture conditions. Fluorescence evaluation of cell viability in 3 D cultures indicated the contribution of apoptotic cell death after ALA-PDT, both with and without iron chelators. Engulfment of remnants of dead cancer cells by macrophages in 2 D cultures was indicated, however, the interaction between macrophages and cancer cells in 3 D cultures subjected to ALA-PDT with or without iron chelators was not present. Conclusions The potential of iron chelators to enhance ALA-PDT was maintained in 3 D collagen matrices. Although PDT dose (ALA concentration, light exposure time) required modification in a cell line-dependent manner to achieve a comparable effect of PDT alone in conventional monolayers and in collagen matrices, the potential of iron chelators to suppress the resistance of esophageal cells to ALA-PDT was not influenced by a fibrillar collagen matrix.

Topical 5-aminolevulinic acid photodynamic therapy for cervical high-grade squamous intraepithelial lesions

ObjectiveTo evaluate the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of high-grade squamous intraepithelial lesions of the cervix (HSIL). MethodsThis retrospective study included 22 female patients with histologically confirmed HSIL and high-risk human papillomavirus (HR-HPV) infections. Patients were treated with ALA-PDT once a week for a total of 6 times. All patients had a follow-up period of 3 months and 6 months. The assessment of effectiveness of ALA-PDT was performed by ThinPrep cytology test (TCT), HPV DNA assay, HPV E6/E7 mRNA examination, colposcopy, biopsy, and immunohistochemistry detection. ResultsThree months after 5-ALA PDT, the histologic disappearance rate was 81.82% (18/22), while the HPV clearance rate was 54.55% (12/22). At the 6 months checkpoint, the HSIL disappearance rate was 90.91% (20/22) and the HPV clearance rate was 86.36% (19/22). Before PDT, 68.18% of patients (15/22) were confirmed with TCT abnormalities, while only one patient (1/22, 4.55%) was abnormal in the TCT test at 6 months checkpoint. All participants were found HPV E6/E7 mRNA positive initially, while the HPV E6/E7 mRNA negative rate was 90.91% (20/22) at 6 months checkpoint. Additionally, we found a significant difference of the expression of CD4+ and CD8+ T cells and HPV E6 and E7 proteins before ALA-PDT and at 3 months follow-up (P < 0.01). No severe side effects were seen. ConclusionsTopical 5-ALA PDT is an effective treatment for cervical HSIL with HR-HPV infection.

Acitretin enhances the cytotoxic effect of 5-aminolevulinic acid photodynamic therapy on squamous cell carcinoma cells

The efficacy of 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) on invasive cutaneous squamous cell carcinoma (cSCC) remains to be improved due to the limited penetration of this treatment. Previous study showed that acitretin and ALA-PDT had synergistic effect on cSCC, but whether acitretin can enhance the cytotoxic effect of ALA-PDT on cSCC is unclear. ObjectiveTo investigate whether acitretin can enhance the cytotoxic effect of ALA-PDT on SCL-1 cells, as well as the possible mechanism involved. MethodsInverted microscopy, trypan blue exclusion assay, and flow cytometry were used to studied the morphology, viability and apoptosis of SCL-1 cells treated with acitretin, ALA-PDT and acitretin followed by ALA-PDT treatment, respectively. Confocal microscopy was applied to detect the ROS formation of SCL-1 cells treated with acitretin of four different concentrations. The ROS formation of SCL-I cells treated with acitretin of four different concentrations followed by ALA-PDT treatment was detected using confocal microscopy and flow cytometry. ResultsSCL-1 cells exhibited a significant morphological alteration when treated with acitretin followed by ALA-PDT. The combination of acitretin and ALA-PDT induced a higher cell death rate and apoptosis than that with acitretin or ALA-PDT treatment alone. ROS could be induced when incubated with acitretin at a concentration of 6.4 × 10−4mg /mL or above. However, a higher level of ROS formation was observed when SCL-1 cells were treated with acitretin followed by ALA-PDT than that with ALA-PDT or acitretin alone. ConclusionAcitretin can enhance the cytotoxic effect of ALA-PDT on SCL-1 cells, possibly via the ROS pathway.

Vitamin D enhances the sensitivity of breast cancer cells to the combination therapy of photodynamic therapy and paclitaxel

PurposeGiven that Vitamin D (VD) has been confirmed to reinforce the toxic effects of 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) towards breast cancer, this study was designed to decipher the combined effects of VD, ALA-PDT and paclitaxel (PTX). MethodsThiazolyl blue tetrazolium bromide assay was conducted to gauge the viability of breast cancer cells treated with ALA-PDT and PTX alone or in combination. The cell migration, invasion and apoptosis were measured by wound healing, transwell and flow cytometry assays, respectively. Xenograft tumor models were established and tumor volume and weight were recorded. The expression of Bcl-2, Bax and cleaved caspase-3 in cells and tumor tissues was determined by western blot assay. ResultsBoth ALA-PDT and PTX alone inhibited viability in a dose-dependent manner, blocked migration and invasion, boosted apoptosis, down-regulated Bcl-2 expression and upregulated the expression of Bax and cleaved caspase-3 in breast cancer cells. More significant effects on the above-mentioned factors were induced by ALA-PDT and PTX in combination. Moreover, ALA-PDT and PTX in combination also suppressed the growth of xenograft tumors and Bcl-2 expression while promoting the expression of Bax and cleaved caspase-3 in tumors. In contrast, VD had no effect on tumor growth and the expression of Bcl-2, Bax and cleavedcaspase-3, but intensified the combined effects of ALA-PDT and PTX. ConclusionVD could enhance the therapeutic effects of ALA-PDT combined with PTX on tumor growth and cell apoptosis.

PD-L1 blockade potentiates the antitumor effects of ALA-PDT and optimizes the tumor microenvironment in cutaneous squamous cell carcinoma

ABSTRACT Immune checkpoint blockade (ICB) is a powerful oncologic treatment modality for a wide variety of human malignancies, but the patient response rate to this treatment remains low, especially in patients with cutaneous squamous cell carcinoma (cSCC). 5-Aminoleuvulinic acid-photodynamic therapy (ALA-PDT) is widely used to treat cancerous and precancerous skin diseases, but the value of ALA-PDT in the treatment of invasive cSCC is debatable. Our previous studies have shown that ALA-PDT can induce antitumor immune responses by promoting the immunogenic death of tumor cells. However, it is unclear whether ALA-PDT exerts synergistic effects with ICB in cSCC. Here, we report that PD-L1 blockade potentiates the antitumor effects of ALA-PDT both on primary and distant tumors, and optimizes the tumor microenvironment in cSCC. In this study, we first detected PD-L1 expression in patients with different grades of cSCC. Then we found the combination of anti-PD-L1 monoclonal antibody (mAb) and ALA-PDT killed tumor cells by apoptosis- and/or ferroptosis-mediated immunogenic cell death (ICD) and stimulated systemic immune response, as well as building the immunological memory response to prevent tumor recurrence. Furthermore, we found that combination therapy can be used to recruit tertiary lymphoid structure (TLS)-like intratumoral lymphoid aggregates, which may promote tumor-infiltrating lymphocyte (TIL)-mediated antitumor immunity. In summary, our work demonstrates that ICB treatment with an anti-PD-L1 antibody is a promising strategy that may potentiate the antitumor effects of ALA-PDT in cSCC.

Effects of ALA-PDT on the macrophages in wound healing and its related mechanisms in vivo and in vitro

BackgroundSeveral studies have suggested the effectiveness of photodynamic therapy (PDT) for wound healing. Macrophages are critical immune cells necessary for regulated inflammation during wound repair. However, the available information regarding the effects of PDT on macrophages during cutaneous wound healing remains insufficient. This study aimed to further investigate these aspects in vivo and in vitro. MethodsMouse full-thickness wound models were used as the study samples to investigate the therapeutic effects and mechanisms of 5-aminolevulinic acid (ALA) PDT. Wound healing rate, granulation tissue formation, local inflammation, M1/M2 macrophages differentiation, were measured at different time points treated by ALA-PDT. The polarization of macrophages induced by ALA-PDT was further evaluated in vitro using PCR and western blot analysis. ResultsALA-PDT could promote formation of granulation tissue, increase inflammatory infiltration and activate M1 macrophages in the early stage of injury. While, ALA-PDT could also facilitate absorption of granulation tissue, inhibit inflammatory infiltration and enhance M2 macrophages polarization in the later stage of wound repair. In vitro, ALA-PDT could modulate the ratio of M2 polarization to M1 polarization via NF-κB signaling pathway. ConclusionsALA-PDT topical application stimulates wound healing by regulating formation of granulation tissue, inflammatory process and M1/M2 macrophages differentiation. The study places a preliminary theoretical basis for topical ALA-PDT to be administered clinically in cutaneous wounds healing.

5-aminolevulinic acid-photodynamic therapy ameliorates cutaneous granuloma by killing drug-resistant Mycobacterium marinum

BackgroundAlthough 5-aminolevulinic acid photodynamic therapy (ALA-PDT) has been extensively used to treat various skin diseases, application for the treatment of cutaneous infection caused by Mycobacterium marinum (M. marinum), especially drug-resistant M. marinum, is unclear. ObjectivesWe evaluated the efficacy of ALA-PDT on M. marinum in a mouse infection model and tested its killing effect on M. marinum in vitro. We also investigated the clinical effect of ALA-PDT on cutaneous granuloma caused by drug-resistant M. marinum. Materials and methodsA total of 9 M. marinum strains isolated from patients were tested for anti-mycobacterial susceptibility. The effects of ALA-PDT on M. marinum in vitro and in mice model were investigated. Therapeutic efficacy was further assessed in two patients with cutaneous granuloma caused by drug- resistant M. marinum. ResultsWe demonstrated that ALA-PDT directly killed M. marinum in vitro. The cutaneous lesions on mouse paws caused by M. marinum were fully recovered 4 weeks after the ALA-PDT treatment. ALA-PDT was also effective in two patients with cutaneous infection caused by drug-resistant M. marinum. The level of intracellular ROS in M. marinum treated with ALA-PDT was significantly higher than that of M. marinum alone. ConclusionsThe results suggest that ALA-PDT is effective in treating M. marinum cutaneous infections by releasing more reactive oxygen species to kill M. marinum directly, and these effects are independent of systemic immune responses. The data highlights that ALA-PDT is a promising therapeutic choice for treatment of M. marinum cutaneous infections, especially drug-resistant M. marinum infections.

In vitro study of the effect of ALA-PDT on Mycobacterium abscessus and its antibiotic susceptibility

BackgroundThe skin infection caused by Mycobacterium abscessus (M. abscessus) is extremely difficult to treat in clinical practice. PDT (photodynamic therapy) is a promising antibacterial treatment. We evaluated the effect of photodynamic therapy using 5-aminolevulinic acid (ALA) as a photosensitizer on M. abscessus and its antibiotic resistance in this study. MethodsM. abscessus and biofilm were treated with different concentrations of ALA and then irradiated with LED light (635 nm, 80 J/cm2), while there were ALA-only group, light-only group, and negative control group. The effects were observed by colony counting, crystal violet staining, confocal laser scanning microscope (CLSM), and scanning electron microscope (SEM). The changes of drug susceptibility of M. abscessus at sublethal doses were detected by micro-broth dilution method, and the possible mechanism was explored by fluorometer and real-time fluorescence quantitative Polymerase Chain Reaction (RT-qPCR). ResultsALA-PDT showed a significant killing effect on M. abscessus at ALA concentrations greater than 50 μg/ml and the effect increased with increasing photosensitizer concentrations. ALA-PDT also showed a notable scavenging effect on M. abscessus biofilm, which was also enhanced with increasing ALA concentrations. At sublethal doses, the susceptibility of M. abscessus to antibiotics was increased, and ALA-PDT greatly increased the cell wall permeability of M. abscessus and decreased the mRNA expression of drug resistance genes whiB7 and erm (41), as well as efflux pump genes MAB_1409c and MAB_3142c at the transcriptional level. ConclusionsALA-PDT has a significant killing effect on M. abscessus and can increase its antibiotic susceptibility.

Photodynamic Effects with 5-Aminolevulinic Acid on Cytokines and Exosomes in Human Peripheral Blood Mononuclear Cells.

Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA), a precursor to the potent photosensitizer, protoporphyrin IX (PpIX), is an established modality for several malignant and premalignant diseases. This treatment is based on the light-activated PpIX in targeted lesions. Although numerous studies have confirmed the necrosis and apoptosis involved in the mechanism of action of this modality, little information is available for the change of exosome levels after treatment. We report from the first study on the effects of ALA-PDT on cytokines and exosomes of human healthy peripheral blood mononuclear cells (PBMCs). The treatment reduced the cytokines and exosomes studied, although there was variation among individual PBMC samples. This reduction is consistent with PDT-mediated survivals of subsets of PBMCs. More specifically, the ALA-PDT treatment apparently decreased all pro-inflammatory cytokines included, suggesting that this treatment may provide a strong anti-inflammatory effect. In addition, the treatment has decreased the levels of different types of exosomes, the HLA-DRDPDQ exosome in particular, which plays an important role in the rejection of organ transplantation as well as autoimmune diseases. These results may suggest future therapeutic strategies of ALA-PDT.

The effect of local photodynamic therapy with 5-aminolevulinic acid in the treatment of vaginal intraepithelial lesions with high-risk HPV infection

BackgroundRecent data has shown increased rate of vaginal intraepithelial neoplasia (VAIN) in younger individuals. Traditional VAIN treatments exert adverse effects on the anatomy and functions of the vagina. Topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is a novel, non-invasive targeted therapy for intraepithelial lesions. Here, we aimed to investigate the efficacy and safety of ALA-PDT in VAIN with high-risk HPV (HR-HPV) infection. MethodsThis study enrolled a total of 82 HR-HPV-positive women diagnosed with VAIN, who were receiving ALA-PDT. The effect of ALA-PDT was evaluated using HPV genotyping and Thinprep cytologic test (TCT). Besides, colposcopy directed biopsies were performed in all patients at 3-month follow-up, and in patients with positive HR-HPV and/or abnormal TCT results during the follow-up period. ResultsOur data showed that the HPV clearance rate was 53.7% (44/82) at 6-month follow-up and 67.1% (55/82) at 12-month follow-up. Patients with HPV16/18 combined with other HR-HPV (HPV16/18 & other HR-HPV) infection, those with a history of hysterectomy and/or older age were had significantly lower HPV clearance rate. Besides, the lesion complete remission (CR) rate was 90.2% (74/82). These results show that HPV16/18 & other HR-HPV infection was associated with significantly lower CR rates. Throughout the follow-up, 2 cases had persistent lesions (2.4%), 6 cases had partial remission (7.3%), 2 cases recurred (2.7%) but none of the patients had disease progression. ConclusionsTaken together, our data showed that ALA-PDT is an effective, safe, and alternative treatment for VAIN patients with HR-HPV infection. However, the ALA-PDT efficacy was relatively poor in patients with older age, HPV16/18 & other HR-HPV infection and/or those with a history of hysterectomy.