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• PDT as a potential strategy for the cutaneous leishmaniasis treatment. • Chloroaluminum phthalocyanine liposomes have good stability and can be used in PDT. • Chloroaluminum phthalocyanine liposomes reduces the leishmania load in lesion and spleen. In the Americas, one of the main causative species of cutaneous leishmaniasis is Leishmania (Leishmania) amazonensis. The systemic antimonials remain the most largely used option for disease control. However, this drug has significant toxicity. The development of new alternative therapies, including the identification of effective drugs for topical treatment of cutaneous leishmaniasis, is of utmost interest. In this sense, photodynamic therapy emerges as a new strategy. The aim of this study was to develop the chloroaluminum phthalocyanine-loaded liposome, characterize it, and evaluate its stability and efficacy in the topical treatment of cutaneous leishmaniasis caused by L. (L.) amazonensis. Liposomes composed of egg phosphatidylcholine were prepared by Bangham's method. Storage stability of phthalocyanine-loaded liposomes was evaluated at 30 and 60 days after preparation. For the in vivo evaluation, the animals were infected with L. (L.) amazonensis and divided into groups: chloroaluminium phthalocyanine-loaded liposome, blank liposome, meglumine antimoniate (200 mgSb+5/Kg/day), and control. The lesion size was determined weekly after the beginning of the treatment. Upon completion, parasites were recovered from the skin lesion and spleen and evaluated by limiting dilution assay. Chloroaluminum phthalocyanine-loaded liposomes were stable and showed adequate characteristics for topical administration. The topical chloroaluminum phthalocyanine-loaded liposome was as effective as systemic pentavalent antimony in reducing the parasitic load in the lesion and spleen in infected animals. The present study showed that photodynamic therapy with chloroaluminum phthalocyanine-loaded liposomes is a promising strategy for the treatment of American cutaneous leishmaniasis caused by L. (L.) amazonensis. [ABSTRACT FROM AUTHOR]

• Global statistics have shown a progressive increase in the incidence of skin cancer. • Photodynamic therapy (PDT) has been shown as a promising innovation for the treatment of skin cancers. • Trials selected here evaluated the effectiveness of different PDT protocols for sBCC. • Randomized clinical trials are required to assess long-term effects of complete therapeutic response provided by PDT. Basal cell cancer (BCC) is an epithelial neoplasm that arises from basal cells, which constitute the lower layer of the epidermis. Global statistics have shown the progressive increase in the incidence of skin cancer in several countries. The cumulative exposure to solar radiation (ultraviolet B) in the first two decades of life represents the critical risk for the disease. Preclinical and clinical trials have shown photodynamic therapy (PDT) as a promising innovation for treatment of skin cancers, especially to the non-melanoma group. The authors reviewed trials with photodynamic therapy in superficial basal cell carcinoma with different photosensitizers to better evaluate how PDT modifies the natural history of sBCC. We conclude trials should not assess only the immediate efficacy but the main goal of long-term effectiveness of the protocols in order to generate best evidence for clinical practice. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT), based on the photoactivation of photosensitizers (PSs), has become a well-studied therapy for cancer. Photofrin ® , belonging to the first generation of PS, is still widely used for the treatment of different kinds of cancers; however, it has several drawbacks that significantly limit its general clinical use. Consequently, there has been extensive research on the design of PS molecules with optimized pharmaceutical properties, with aiming of overcoming the disadvantages of traditional PS, such as poor chemical purity, long half-life, excessive accumulation into the skin, and low attenuation coefficients. The rational design of novel PS with desirable properties has attracted considerable research in the pharmaceutical field. This review presents an overview on the classical photosensitizers and the most significant recent advances in the development of PS with regard to their potential application in oncology. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the viability of human dental pulp cells from extracted teeth kept at standard room temperature and atmospheric pressure for different periods of time. Twenty-one healthy permanent teeth were used. They were divided into five groups according to the expected time from extraction to processing. One group was tested immediately after extraction; the other groups were each tested at one of the following time points: 30 minutes, 1 hour, 2 hours, and 5 hours post-extraction. Cell morphology was analysed by light microscopy; cell proliferation was analysed using MTT assay and by counting the viable cells in a haemocytometer. Similar results were observed in all groups (p < 0.05). A delay of up to five hours for tooth processing and tissue collection does not preclude the establishment of dental pulp cell cultures, affect the morphology of these cells, or reduce their proliferative potential. [ABSTRACT FROM AUTHOR]

• Nanovesicular formulation of OR141 (ORN) could selectively eradicate leukemia cells. • ORN could increase the photosensitizer biodistribution. • In the absence of light, ORN is not toxic for ovarian stromal cells. • Before ovarian autotransplantation, ORN-PDT can potentially be employed as a selective tissue purging strategy to eradicate malignant cells. In 2020, the estimated number of new leukemia cases was higher than 30,000 in girls between 0 and 19 years old. Due to cancer treatment, some of these patients may lose both endocrine and reproductive functions. Transplantation of cryopreserved ovarian tissue is not advised after cancer remission because it has a high risk of reintroducing malignant cells in the patient, potentially leading to leukemia recurrence. To safely transplant the ovarian tissue from these patients and restore their fertility, our goal was to develop a photodynamic therapy (PDT) strategy to eliminate leukemia ex vivo. To this end, we designed, optimized, and characterized OR141-loaded niosomes (ORN) to develop the most effective formulation for ex vivo purging ovarian fragments from chronic myelogenous leukemia cells. After establishing the best ORN formulation, the PDT efficiency of optimized ORN was determined for human ovarian stromal cells and acute myeloid leukemia cell line (HL60). Blank niosomes treatment on ovarian stromal cells causes no significant toxicity, showing that the composition of the nanoparticle is not toxic. On the other hand, the in vitro studies showed that while ovarian stromal cells were still viable (82.04 ± 2.79%) after the treatment by 0.5 µM ORN, the same treatment yielded 95.43 ± 3.89% toxicity and cell death in the cancer cells. In conclusion, our results showed that our novel PDT procedure could be a promising strategy to destroy leukemia cells in ovarian tissue fragments allowing safe transplantation in cancer survivors. [ABSTRACT FROM AUTHOR]

Background Photodynamic therapy (PDT) uses photosensitizing agents, which are delivered in target cells, followed by local application of visible light in specific wavelengths. This reaction produce reactive oxygen species able to induce cell death by apoptosis or necrosis, injured to the local vasculature, and exert important effects on the immune system. Objective The present work evaluated the clinical findings, histomorphological alterations and immunodetection of VEGF after PDT using chloro-aluminum phthalocyanine (AlClPc) entrapped in a lipid nanoemulsion in a split-mouth clinical trial. Material and methods Eight healthy volunteers with clinical indication for extraction were included in the study. Seven days before the extraction 40 ul of nanoemulsion AlClPc 5 μM was injected into gingival tissue followed by irradiation with diode laser, the contralateral side was used as control. Tissue specimens were removed seven days after the PDT and divided into two groups (test and control groups) for histological and immunohistochemical analysis. Patients were monitored at days, 0, 7, 14 and 30 to assess adverse effects of the therapy. Results The therapy was well tolerated by all patients. Adverse effects were short-time and completely reversible. Areas of edema, vascular congestion, and intense vascularization were viewed in gingival samples that received PDT. Additionally, dystrophic calcification was observed in subepithelial region. VEGF showed moderate to strong immunostaining in specimens subjected to PDT. Conclusions Taken together, the results showed that the protocol used in this study mediated by nanoemulsion containing AlClPc is safe for clinical application in gingival tissue and suggests that VEGF is increased after PDT. [ABSTRACT FROM AUTHOR]

• PDT process highly depends on the light characteristics and photosensitizer's concentration, so they need to be optimized to obtain the most effective protocol. • PDT can be employed as a selective purging strategy to eradicate malignant cells in ovarian tissue fragments before their autotransplantation. • PDT based on AlPc and ZnPc can selectively eradicate the leukemic cells without significant damage to ovarian cells. • In the absence of light, AlPc and ZnPc are not toxic for ovarian stromal cells. Due to the risk of reintroducing malignant cells, autotransplantation of cryopreserved ovarian tissue is not allowed in leukemia patients. In order to restore fertility in these patients, ex vivo purging of ovarian fragments could be proposed as a strategy to eradicate malignant cells before grafting. Photodynamic therapy (PDT), as a clinical-approved modality, is a minimally invasive and selective therapeutic for eliminating malignant cells. The present work aims therefore to evaluate the phototoxicity of two photosensitizers (aluminum phthalocyanine (AlPc) and zinc phthalocyanine (ZnPc)) on leukemia cells. To this end, two lines of malignant cells (K562 and HL-60) and isolated ovarian stromal cells (control) were treated by PDT using a diode laser with various energy densities. Cell viability after the treatment, the amount of generated reactive oxygen species, dark toxicity of the photosensitizers, and single-cell morphology were studied. Our results demonstrated that using irradiation with the energy density of 10 J/cm2, 1 µM AlPc could significantly reduce the viability of K562 (4.73 ± 0.14%) and HL-60 (2.74 ± 0.31%). Similarly, the viability of these cells was reduced (K562 cells: 3.84 ± 0.81%; HL-60 cells: 6.82 ± 3.21%) with 1 µM ZnPc and an energy density of 50 J/cm2. On the other hand, these PDT protocols had no significant effect on stromal cells. These findings indicate that our approach can be a promising strategy for the safe restoration of fertility in leukemia patients. However, further studies are necessary to assess its efficiency in ovarian fragments containing malignant cells to determine their eradication rate and the effect of our treatment on the survival of stromal cells and preantral follicles. [ABSTRACT FROM AUTHOR]

• Aluminum-phthalocyanine delivered by nanoemulsion accumulated into Cryptococcus spp. cells. • Photodynamic therapy led to a photosensitizer concentration-dependent Cryptococcus spp. inhibition. • Sodium butyrate and trichostatin A enhanced the inhibitory effect of photodynamic therapy. Cryptococcosis is a disseminated infection caused mainly by C. neoformans and C. gattii. Limitations for the treatment involve the selection of isolates resistant to conventional antifungal drugs, prolonged treatment time and drugs side effects. This study evaluated the combined effect of histone deacetylase inhibitors (HDACi) and photodynamic therapy (PDT) on the growth of C. neoformans and C. gattii in vitro. Results showed that PDT inhibited yeasts proliferation and enhanced the HDACi-mediated cell viability impairment in Cryptococcus spp. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to analyze cytokine profiles after application of photodynamic therapy (PDT) in gingival tissues of rats with ligature-induced periodontal disease (PD). Periodontal disease was induced through the introduction of a cotton thread around the first left mandibular molar, while the right side molars did not receive ligatures. After 7 days of PD evolution, ligatures were removed, and animals were randomly divided into the following treatment groups: I, rats without treatment; II, rats received chloroaluminum phthalocyanine (AlClPc); III, rats received low-level laser alone; and IV, rats received AlClPc associated with low-level laser. The animals were killed 7 days after the treatments, and the mandibles were histologically processed to assess morphologic and immunohistochemical profile, while gingival tissues were removed for quantification of tumor necrosis factor α (TNF-α), interleukin (IL) 1 β and IL-10 expression (by enzyme-linked immunosorbent assay). Histomorphologic analysis of periodontal tissues demonstrated that PDT-treated animals show tissue necrosis as well as lower TNF-α expression compared with ligatured animals treated with AlClPc alone. It was concluded that PDT using AlClPc entrapped in a lipid nanoemulsion may be useful in therapies because of immunomodulatory effects that decreased the inflammatory response and caused tissue destruction. [ABSTRACT FROM AUTHOR]