Anthraquinone encapsulation into polymeric nanocapsules as a new drug from biotechnological origin designed for photodynamic therapy

Photodynamic Therapy as a Novel Therapeutic Modality Applying Quinizarin-Loaded Nanocapsules and 3D Bioprinting Skin Permeation for Inflammation Treatment

Skin inflammation associated with chronic diseases involves a direct role of keratinocytes in its immunopathogenesis, triggering a cascade of immune responses. Despite this, highly targeted treatments remain elusive, highlighting the need for more specific therapeutic strategies. In this study, nanocapsules containing quinizarin (QZ/NC) were developed and evaluated in an in vitro model of keratinocyte-mediated inflammation, incorporating the action of photodynamic therapy (PDT) and analyzing permeation in a 3D skin model. Comprehensive physicochemical, stability, cytotoxicity, and permeation analyses of the nanomaterials were conducted. The nanocapsules demonstrated desirable physicochemical properties, remained stable throughout the analysis period, and exhibited no spectroscopic alterations. Cytotoxicity tests revealed no toxicity at the lowest concentrations of QZ/NC. Permeation and cellular uptake studies confirmed QZ/NC permeation in 3D skin models, along with intracellular incorporation and internalization of the drug, thereby enhancing its efficacy in drug delivery. The developed model for inducing the inflammatory process in vitro yielded promising results, particularly when the synthesized nanomaterial was combined with PDT, showing a reduction in cytokine levels. These findings suggest a potential new therapeutic approach for treating inflammatory skin diseases.

Development of 3D skin equivalents for application in photodynamic biostimulation therapy assays using curcumin nanocapsules

For decades, animal models have been the standard approach in drug research and development, as they are required by regulations in the transition from preclinical to clinical trials. However, there is growing ethical and scientific concern regarding these trials, as 80 % of the therapeutic potential observed in pre-clinical studies are often unable to be replicated, despite demonstrating efficacy and safety. In response to this, Tissue Engineering has emerged as a promising alternative that enables the treatment of various diseases through the production of biological models for advanced biological assays or through the direct development of tissue repairs or replacements. One of the promising applications of Tissue Engineering is the development of three-dimensional (3D) models for in vitro tests, replacing the need for in vivo animal models. In this study, 3D skin equivalents (TSE) were produced and used as an in vitro model to test photobiostimulation using curcumin-loaded nanocapsules. Photodynamic biostimulation therapy uses photodynamic processes to generate small amounts of reactive oxygen species (ROS), which can activate important biological effects such as cell differentiation, modulation of inflammatory processes and contribution to cell regeneration. The PLGA nanocapsules (NC) used in the study were synthesized through a preformed polymer deposition method, exhibiting particle size <200 nm, Zeta potential >|30| and polydispersity index between 0.5 and 0.3. Atomic force microscopy analyzes confirmed that the particle size was <200 nm, with a spherical morphology and a predominantly smooth and uniform surface. The NC biocompatibility assay did not demonstrate cytotoxicity for the concentrations tested (2.5-25 μg mL-1).The in vitro release assay showed a slow and sustained release characteristic of the nanocapsules, and cellular uptake assays indicated a significant increase in cellular internalization of the curcumin-loaded nanostructure. Monolayer photobiostimulation studies revealed an increase in cell viability of the HDFn cell line (viability 134 %-228 %) for all LED fluences employed at λ = 450 nm (150, 300, and 450 mJ cm-2). Additionally, the scratch assays, monitoring in vitro scar injury, demonstrated more effective effects on cell proliferation with the fluence of 300 mJ cm-2. Staining of TSE with hematoxylin and eosin showed the presence of cells with different morphologies, confirming the presence of fibroblasts and keratinocytes. Immunohistochemistry using KI-67 revealed the presence of proliferating cells in TSE after irradiation with LED λ = 450 nm (150, 300, and 450 mJ cm-2).

The enhanced cytotoxicity on breast cancer cells by Tanshinone I-induced photodynamic effect

Recently, natural photosensitizers, such as berberine, curcumin, riboflavin, and emodin, have received more and more attention in photodynamic therapy. Tanshinone I (TanI) is extracted from a traditional Chinese herb Danshen, and exhibits many physiological functions including antitumor. TanI is a photoactive phytocompounds, but no work was tried to investigate its potential photodynamic effect. This study evaluated the cytotoxicity induced by the photodynamic effect of TanI. The photochemical reactions of TanI were firstly investigated by laser flash photolysis. Then breast cancer cell line MDA-MB-231 was chosen as a model and the photodynamic effect of TanI on cancer cell was evaluated by MTT assay and flow cytometry. The results showed that TanI could be photoexcited by its UV-Vis absorption light to produce 3TanI* which was quickly quenched by O2. MTT assay showed that the photodynamic effect of TanI resulted in more obvious inhibitive effect on cell survival and cell migration. Besides, the photodynamic effect of TanI could induce cell apoptosis and necrosis, lead to cell cycle arrest in G2, increase intracellular ROS, and decrease the cellular Δψm. It can be concluded that the photodynamic effect of TanI can obviously enhance the cytotoxicity of TanI on MDA-MB-231 cells in vitro, which indicated that TanI might serve as a natural photosensitizer.

PEGylated and functionalized polylactide-based nanocapsules: An overview

Polymeric nanocapsules (NC) are versatile mixed vesicular nanocarriers, generally containing a lipid core with a polymeric wall. They have been first developed over four decades ago with outstanding applicability in the cosmetic and pharmaceutical fields. Biodegradable polyesters are frequently used in nanocapsule preparation and among them, polylactic acid (PLA) derivatives and copolymers, such as PLGA and amphiphilic block copolymers, are widely used and considered safe for different administration routes. PLA functionalization strategies have been developed to obtain more versatile polymers and to allow the conjugation with bioactive ligands for cell-targeted NC. This review intends to provide steps in the evolution of NC since its first report and the recent literature on PLA-based NC applications. PLA-based polymer synthesis and surface modifications are included, as well as the use of NC as a novel tool for combined treatment, diagnostics, and imaging in one delivery system. Furthermore, the use of NC to carry therapeutic and/or imaging agents for different diseases, mainly cancer, inflammation, and infections is presented and reviewed. Constraints that impair translation to the clinic are discussed to provide safe and reproducible PLA-based nanocapsules on the market. We reviewed the entire period in the literature where the term "nanocapsules" appears for the first time until the present day, selecting original scientific publications and the most relevant patent literature related to PLA-based NC. We presented to readers a historical overview of these Sui generis nanostructures.

Investigation of ROS generating capacity of curcumin-loaded liposomes and its in vitro cytotoxicity on MCF-7 cell lines using photodynamic therapy

Photodynamic therapy (PDT) is highly efficient in eradicating targetlesions by using photosensitizers (PS) triggered by external light energy. Nanotechnology may help increase the solubility and effective delivery of PS towards improving its efficacy. Curcumin (Cur) was used as a natural PS for PDT in the present work. Briefly, curcumin was encapsulated in liposomes (LPs) using the thin film hydration method and optimized using the QbD approach through the Box-Behnken Design (BBD) to optimize the responses like entrapment efficiency and drug loading with a smaller vesicle size. The in vitro release studies performed using a dialysis bag (MWCO 12 KDa) suggested a sustained release of the Cur over 72 h in pH 7.4 PBS following the Weibull drug release kinetics. In addition, the ROS generating capabilities upon application of blue light (460 nm) and resulting cytotoxicity were evaluated in MCF-7 cell lines. The Cur-loaded liposome exhibited significant ROS generation and cytotoxicity to the cancer cells than free curcumin. Thus, the Cur-loaded liposomes could be used to treat breast cancer with photodynamic therapy.

Advanced methylene blue - nanoemulsions for in vitro photodynamic therapy on oral and cervical human carcinoma

Photodynamic therapy (PDT) is a therapeutic modality with high contributions in the treatment of cancer. This approach is based on photophysical principles, which presents as a less invasive strategy than conventional therapies. Combined with nanotechnology, the therapy becomes more efficient because nanoparticles (NPs) have advantageous characteristics such as biocompatibility, controlled, and targeted release, promoting solubility and decreasing the toxicity and side effects involved. In this work were developed nanoemulsions containing the methylene blue photosensitizer (MB) (MB/NE) and in the empty form (unloaded/NE). Subsequently, the mentioned nanomaterials were characterized by the measurement of dynamic light scattering (DLS). The MB/NE and unloaded/NE showed appropriate physical and chemical characteristics, with particle size ≤ 200 nm, polydispersity index close to 0.3, and zeta potential exhibiting negative charge, showing stable values during the analysis. The incorporation of the MB did not cause changes in the photophysical profile of the photosensitizer. The quantification performed showed an incorporation rate of 81.9%. Viability studies showed an absence of cytotoxicity for MB/NE in the concentrations of 10-75 µmol·L^-1, free MB at the concentration of 75 µmol·L^-1, and unloaded NE 47.5% (v/v), presenting viability close to 90%, respectively. PDT in vitro protocols applied to OSCC and HeLa cells showed a decrease in cell viability through only one irradiation, evidencing the photodynamic activity of the formulation when applied to cancer cells. The results obtained were superior to those found in the literature where they use free MB, showing that the association between nanotechnology and PDT optimizes the proposed protocol. From the results obtained, it is possible to indicate that the NE have high stability, with satisfactory physical-chemical parameters, in addition to not presenting cytotoxicity in the tested concentrations, showing their in vitro biocompatibility, in addition to presenting satisfactory effects when combined MB/NE with PDT, showing the potential of MB/NE as a very promising nanostructured photosensitizer for the treatment of some types of cancer.

Development of Biotechnological Photosensitizers for Photodynamic Therapy: Cancer Research and Treatment-From Benchtop to Clinical Practice

Photodynamic therapy (PDT) is a noninvasive therapeutic approach that has been applied in studies for the treatment of various diseases. In this context, PDT has been suggested as a new therapy or adjuvant therapy to traditional cancer therapy. The mode of action of PDT consists of the generation of singlet oxygen (¹O₂) and reactive oxygen species (ROS) through the administration of a compound called photosensitizer (PS), a light source, and molecular oxygen (³O₂). This combination generates controlled photochemical reactions (photodynamic mechanisms) that produce ROS, such as singlet oxygen (¹O₂), which can induce apoptosis and/or cell death induced by necrosis, degeneration of the tumor vasculature, stimulation of the antitumor immune response, and induction of inflammatory reactions in the illuminated region. However, the traditional compounds used in PDT limit its application. In this context, compounds of biotechnological origin with photosensitizing activity in association with nanotechnology are being used in PDT, aiming at its application in several types of cancer but with less toxicity toward neighboring tissues and better absorption of light for more aggressive types of cancer. In this review, we present studies involving innovatively developed PS that aimed to improve the efficiency of PDT in cancer treatment. Specifically, we focused on the clinical translation and application of PS of natural origin on cancer.

An Update on Photodynamic Therapy of Psoriasis—Current Strategies and Nanotechnology as a Future Perspective

Psoriasis (PS) is an immune-mediated skin disease with substantial negative effects on patient quality of life. Despite significant progress in the development of novel treatment options over the past few decades, a high percentage of patients with psoriasis remain undertreated and require new medications with superior long-term efficacy and safety. One of the most promising treatment options against psoriatic lesions is a form of phototherapy known as photodynamic therapy (PDT), which involves either the systemic or local application of a cell-targeting photosensitizing compound, followed by selective illumination of the lesion with visible light. However, the effectiveness of clinically incorporated photosensitizers in psoriasis treatment is limited, and adverse effects such as pain or burning sensations are frequently reported. In this study, we performed a literature review and attempted to provide a pooled estimate of the efficacy and short-term safety of targeted PDT in the treatment of psoriasis. Despite some encouraging results, PDT remains clinically underutilized. This highlights the need for further studies that will aim to evaluate the efficacy of a wider spectrum of photosensitizers and the potential of nanotechnology in psoriasis treatment.

Charged groups on pyropheophorbide-based photosensitizers dictate uptake by tumor cells and photodynamic therapy efficacy

This study investigated the impact of anionic and cationic substituents of the pyropheophorbide-based photosensitizers (PS) on uptake and retention by tumor epithelial cells and photodynamic therapy (PDT). A series of PSs were generated that bear carboxylic acid functionalities, alkyl amines with variable length of carbon units or as a quaternary ammonium salt introduced at position 17² of 3-(1'-hexyloxy)ethyl-3-devinylpyropheophorbide-a (HPPH). The nature of the functionalities in the macrocycle made a significant difference in overall lipophilicity (log D values at pH 7.4), and in binding to and retention by human and murine tumor cells. Depending on the presence of functional groups, the PSs showed a change in cellular uptake from diffusion to endocytosis and in the preference for subcellular localization to mitochondria/ER or lysosomes. Two and more carboxylic groups drastically reduced uptake by all cell types. In contrast, PSs with amine and quaternary amine salt showed higher cellular binding, uptake and in vitro PDT efficacy than HPPH. The enhanced cellular uptake of the cationic PSs was accompanied by a loss of tumor cell specificity and contributed to severe systemic toxicity in tumor-bearing mice intravenously injected with the PS and subjected to investigate their therapeutic potential.

The Health Benefits of Emodin, a Natural Anthraquinone Derived from Rhubarb-A Summary Update

Emodin (6-methyl-1,3,8-trihydroxyanthraquinone) is a naturally occurring anthraquinone derivative found in roots and leaves of various plants, fungi and lichens. For a long time it has been used in traditional Chinese medicine as an active ingredient in herbs. Among other sources, it is isolated from the rhubarb Rheum palmatum or tuber fleece-flower Polygonam multiflorum. Emodin has a wide range of biological activities, including diuretic, antibacterial, antiulcer, anti-inflammatory, anticancer and antinociceptive. According to the most recent studies, emodin acts as an antimalarial and antiallergic agent, and can also reverse resistance to chemotherapy. In the present work the potential therapeutic role of emodin in treatment of inflammatory diseases, cancers and microbial infections is analysed.

Polymeric nanocapsules: A review on design and production methods for pharmaceutical purpose

Polymeric nanocapsules have extensive application potential in medical, biological, and pharmaceutical fields, and, therefore, much research has been dedicated to their production. Indeed, production protocols and the materials used are decisive for obtaining the desired nanocapsules characteristics and biological performance. In addition to that, several technological strategies have been developed in the last decade to improve processing techniques and form more valuable nanocapsules. This review provides a guide to current methods for developing polymeric nanocapsules, reporting aspects to be considered when choosing appropriate materials, and discussing different ways to produce nanocapsules for superior performances.

Copolymer-nanocapsules of zinc phenyl-thio-phthalocyanine and amphotericin-B in association with antimicrobial photodynamic therapy (A-PDT) applications against Candida albicans yeasts

Antimicrobial Photodynamic Therapy (A-PDT) is a modern and non-invasive therapeutic modality. Nanostructures like the polymeric nanocapsules (NC) has proved to be a system that has enormous potential to improve current antimicrobial therapeutic practice. NC of Zinc phenyl-thio-phthalocyanine and Amphotericin B association (NC/ZnS4Pc + AMB) built with poly(lactide-co-glycolide) (PLGA) 50:50 using the preformed polymer interfacial deposition method were developed at a 0.05 mg mL^{- 1} theoretical concentration to improve antifungal activity with two actives association and assistance from PDTa. It showed an average particle diameter of 253.8 ± 17.3, an average polydispersity index of 0.36 ± 0.01, and a negative Zeta potential average of -31.03 ± 5.54 for 158 days. UV-vis absorption and emission spectroscopy analyses did not show changes in photophysical properties in the steady-state of NC/ZnS4Pc + AMB counterparts free ZnS4Pc. The encapsulation percentage of actives was 89.24 % and 7.40 % for ZnS4Pc and AMB, respectively. Cell viability assay using NIH/3T3 ATCC® CRL-1658 ™ cells line showed no cytotoxicity for the concentrations tested. The photodynamic activity assay using NC/ZnS4Pc + AMB diluted showed fungal toxicity against Candida albicans yeast with energetic fluences of 12 J.cm^-2 and 25 J.cm^-2 by a decrease in cell viability. The MFC assay demonstrated a fungistatic activity for the conditions employed in the PDTa assay. The results show that NC/ZnS4Pc + AMB is a promising nanomaterial for antimicrobial inactivation using PDT.

Metal organic frameworks (MOFs) with therapeutic and biomedical applications: a patent review

Introduction: Metal organic frameworks (MOFs) are a recent group of nano porous materials with exceptional physical properties, such as large surface areas, high pore volumes, low densities and well-defined pores. This type of material has been used frequently for biomedical and therapeutic applications, such as drug delivery systems and theranostic materials.Areas covered: In this review, the authors searched for patents filed in the last 10 years, found in different databases, related to the therapeutic or biomedical application of MOFs for use in different health fields. The possibility of these new materials becoming new therapeutic possibilities available to the population was emphasized.Expert opinion: The advances in research with MOFs have grown in the last 10 years and with that many possibilities for their applications have emerged in several areas, especially biomedical. The possibility of using these materials in drug delivery systems is the most common form of possibility of use in the health area, mainly due to easy obtaining and high reproducibility, which are seen very positively by the drug development technology sector.

Non-Oncologic Applications of Nanomedicine-Based Phototherapy

Phototherapy is widely applied to various human diseases. Nanomedicine-based phototherapy can be classified into photodynamic therapy (PDT) and photothermal therapy (PTT). Activated photosensitizer kills the target cells by generating radicals or reactive oxygen species in PDT while generating heat in PTT. Both PDT and PTT have been employed for treating various diseases, from preclinical to randomized controlled clinical trials. However, there are still hurdles to overcome before entering clinical practice. This review provides an overview of nanomedicine-based phototherapy, especially in non-oncologic diseases. Multiple clinical trials were undertaken to prove the therapeutic efficacy of PDT in dermatologic, ophthalmologic, cardiovascular, and dental diseases. Preclinical studies showed the feasibility of PDT in neurologic, gastrointestinal, respiratory, and musculoskeletal diseases. A few clinical studies of PTT were tried in atherosclerosis and dry eye syndrome. Although most studies have shown promising results, there have been limitations in specificity, targeting efficiency, and tissue penetration using phototherapy. Recently, nanomaterials have shown promising results to overcome these limitations. With advanced technology, nanomedicine-based phototherapy holds great potential for broader clinical practice.