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Cells Dec 2022Photodynamic therapy (PDT) has been used in recent years as a non-invasive treatment for cancer, due to the side effects of traditional treatments such as surgery,... (Review)
Review
Photodynamic therapy (PDT) has been used in recent years as a non-invasive treatment for cancer, due to the side effects of traditional treatments such as surgery, radiotherapy, and chemotherapy. This therapeutic technique requires a photosensitizer, light energy, and oxygen to produce reactive oxygen species (ROS) which mediate cellular toxicity. PDT is a useful non-invasive therapy for cancer treatment, but it has some limitations that need to be overcome, such as low-light-penetration depths, non-targeting photosensitizers, and tumor hypoxia. This review focuses on the latest innovative strategies based on the synergistic use of other energy sources, such as non-visible radiation of the electromagnetic spectrum (microwaves, infrared, and X-rays), ultrasound, and electric/magnetic fields, to overcome PDT limitations and enhance the therapeutic effect of PDT. The main principles, mechanisms, and crucial elements of PDT are also addressed.
Topics: Humans; Photochemotherapy; Photosensitizing Agents; Neoplasms; Oxygen; X-Rays
PubMed: 36552759
DOI: 10.3390/cells11243995 -
Biomolecular Concepts Mar 2022Photodynamic therapy (PDT) is a clinically approved procedure that can exert a curative action against malignant cells. The treatment implies the administration of a...
Photodynamic therapy (PDT) is a clinically approved procedure that can exert a curative action against malignant cells. The treatment implies the administration of a photoactive molecular species that, upon absorption of visible or near infrared light, sensitizes the formation of reactive oxygen species. These species are cytotoxic and lead to tumor cell death, damage vasculature, and induce inflammation. Clinical investigations demonstrated that PDT is curative and does not compromise other treatment options. One of the major limitations of the original method was the low selectivity of the photoactive compounds for malignant over healthy tissues. The development of conjugates with antibodies has endowed photosensitizing molecules with targeting capability, so that the compounds are delivered with unprecedented precision to the site of action. Given their fluorescence emission capability, these supramolecular species are intrinsically theranostic agents.
Topics: Humans; Neoplasms; Photochemotherapy; Photosensitizing Agents; Reactive Oxygen Species
PubMed: 35304984
DOI: 10.1515/bmc-2022-0010 -
Journal of Nanobiotechnology Oct 2021Photoactivation targeting macrophages has emerged as a therapeutic strategy for atherosclerosis, but limited targetable ability of photosensitizers to the lesions...
BACKGROUND
Photoactivation targeting macrophages has emerged as a therapeutic strategy for atherosclerosis, but limited targetable ability of photosensitizers to the lesions hinders its applications. Moreover, the molecular mechanistic insight to its phototherapeutic effects on atheroma is still lacking. Herein, we developed a macrophage targetable near-infrared fluorescence (NIRF) emitting phototheranostic agent by conjugating dextran sulfate (DS) to chlorin e6 (Ce6) and estimated its phototherapeutic feasibility in murine atheroma. Also, the phototherapeutic mechanisms of DS-Ce6 on atherosclerosis were investigated.
RESULTS
The phototheranostic agent DS-Ce6 efficiently internalized into the activated macrophages and foam cells via scavenger receptor-A (SR-A) mediated endocytosis. Customized serial optical imaging-guided photoactivation of DS-Ce6 by light illumination reduced both atheroma burden and inflammation in murine models. Immuno-fluorescence and -histochemical analyses revealed that the photoactivation of DS-Ce6 produced a prominent increase in macrophage-associated apoptotic bodies 1 week after laser irradiation and induced autophagy with Mer tyrosine-protein kinase expression as early as day 1, indicative of an enhanced efferocytosis in atheroma.
CONCLUSION
Imaging-guided DS-Ce6 photoactivation was able to in vivo detect inflammatory activity in atheroma as well as to simultaneously reduce both plaque burden and inflammation by harmonic contribution of apoptosis, autophagy, and lesional efferocytosis. These results suggest that macrophage targetable phototheranostic nanoagents will be a promising theranostic strategy for high-risk atheroma.
Topics: Animals; Apoptosis; Atherosclerosis; Autophagy; Cell Line, Tumor; Endocytosis; Foam Cells; Infrared Rays; Male; Mice; Mice, Knockout; Photochemotherapy; Photosensitizing Agents; RAW 264.7 Cells; Theranostic Nanomedicine
PubMed: 34689768
DOI: 10.1186/s12951-021-01084-z -
Advanced Drug Delivery Reviews Dec 2021With rapid emergence of multi-drug resistant microbes, it is imperative to seek alternative means for infection control. Optical waveguides are an auspicious delivery... (Review)
Review
With rapid emergence of multi-drug resistant microbes, it is imperative to seek alternative means for infection control. Optical waveguides are an auspicious delivery method for precise administration of phototherapy. Studies have shown that phototherapy is promising in fighting against a myriad of infectious pathogens (i.e. viruses, bacteria, fungi, and protozoa) including biofilm-forming species and drug-resistant strains while evading treatment resistance. When administered via optical waveguides, phototherapy can treat both superficial and deep-tissue infections while minimizing off-site effects that afflict conventional phototherapy and pharmacotherapy. Despite great therapeutic potential, exact mechanisms, materials, and fabrication designs to optimize this promising treatment option are underexplored. This review outlines principles and applications of phototherapy and optical waveguides for infection control. Research advances, challenges, and outlook regarding this delivery system are rigorously discussed in a hope to inspire future developments of optical waveguide-mediated phototherapy for the management of infection and beyond.
Topics: Communicable Diseases; Humans; Low-Level Light Therapy; Nanoparticle Drug Delivery System; Photochemotherapy; Photosensitizing Agents
PubMed: 34740763
DOI: 10.1016/j.addr.2021.114036 -
Indian Journal of Dental Research :... 2015Periodontal disease results from inflammation of the supporting structure of the teeth and in response to chronic infection caused by various periodontopathic bacteria.... (Review)
Review
Periodontal disease results from inflammation of the supporting structure of the teeth and in response to chronic infection caused by various periodontopathic bacteria. The mechanical removal of this biofilm and adjunctive use of antibacterial disinfectants and antibiotics have been the conventional methods of periodontal therapy. However, the removal of plaque and the reduction in the number of infectious organisms can be impaired in sites with difficult access. Photodynamic therapy (PDT) is a powerful laser-initiated photochemical reaction, involving the use of a photoactive dye (photosensitizer) activated by light of a specific wavelength in the presence of oxygen. Application of PDT in periodontics such as pocket debridement, gingivitis, and aggressive periodontitis continue to evolve into a mature clinical treatment modality and is considered as a promising novel approach for eradicating pathogenic bacteria in periodontitis.
Topics: Humans; Periodontal Diseases; Periodontics; Photochemotherapy; Photosensitizing Agents
PubMed: 26481895
DOI: 10.4103/0970-9290.167636 -
International Journal of Molecular... Mar 2024The origins of photodynamic therapy (PDT) date back to 1904. Since then, the amount of research proving PDT and, consequently, its applicability to various disease... (Review)
Review
The origins of photodynamic therapy (PDT) date back to 1904. Since then, the amount of research proving PDT and, consequently, its applicability to various disease states has steadily increased. Currently, PDT is mainly used in oncology to destroy cancer cells. It is being worked on for possible use in other medical fields as well, including cardiology. It can be used in the prevention of restenosis, often occurring after vascular surgical interventions, for destroying atherosclerotic plaques and as a new ablative method of ectopic centers in the treatment of atrial fibrillation. The purpose of this review is to summarize the knowledge to date regarding the therapeutic potential of using PDT for various pathological conditions in cardiology. The review also focuses on the current limitations associated with the use of PDT and identifies areas where more research is needed to develop better drug regimens. Materials and methods: The study analyzed 189 medical articles. The articles came from PubMed, Frontiers, Google Scholar, Science Direct and Web of Science databases. Through the excitation of light, a photosensitizer (PS) introduced into the body, the destruction of pathological cells occurs. PTD is widely used in oncology of the central nervous system (CNS). This process is made possible by the production of free oxygen radicals (ROS) and singlet oxygen, which generate oxidative stress that destroys sensitive cancer cells. In recent years, photosensitizers have also been discovered to have a strong affinity for macrophages that fill atherosclerotic plaques, making these compounds suitable for treating atherosclerosis. By inducing apoptosis of smooth muscle cells, inactivating basic fibroblast growth factor (FGF-β) and inhibiting endothelial cell hyperplasia, PDT can be used to prevent restenosis after surgical proceduresPDT appears to be a minimally invasive and highly effective therapeutic method, especially when combined with other therapeutic methods. Unfortunately, the small number of animal model studies and human clinical trials greatly limit the applicability of PDT on a wider scale. Current limitations, such as the depth of penetration, delivery of photosensitizer particles to the direct site of the lesion or the appropriate choice of photosensitizer in relation to the nature of the pathology, unfortunately make it impossible to replace current therapeutic approaches.
Topics: Animals; Humans; Photosensitizing Agents; Photochemotherapy; Plaque, Atherosclerotic; Free Radicals; Cardiology
PubMed: 38542180
DOI: 10.3390/ijms25063206 -
Postepy Higieny I Medycyny... Feb 2014Photodynamic therapy (PDT) is a special type of treatment involving the use of a photosensitizer or a photosensitizing agent along with a special type of light, which,... (Review)
Review
Photodynamic therapy (PDT) is a special type of treatment involving the use of a photosensitizer or a photosensitizing agent along with a special type of light, which, combined together, induces production of a form of oxygen that is used to kill surrounding cells in different areas of the human body. Specification of the head and neck region requires different approaches due to the surrounding of vital structures. PDT can also be used to treat cells invaded with infections such as fungi, bacteria and viruses. The light beam placed in tumor sites activates locally applied drugs and kills the cancer cells. Many studies are taking place in order to invent better photosensitizers, working on a larger scale and to treat deeply placed and larger tumors. It seems that PDT could be used as an alternative surgical treatment in some tumor types; however, all clinicians should be aware that the surgical approach is still the treatment of choice. PDT is a very accurate and effective therapy, especially in early stages of head and neck squamous cell carcinomas (HNSCC), and can greatly affect surgical outcomes in cancerous patients. We present a detailed review about photosensitizers, their use, and therapeutic advantages and disadvantages.
Topics: Carcinoma, Squamous Cell; Head and Neck Neoplasms; Humans; Photochemotherapy; Photosensitizing Agents; Squamous Cell Carcinoma of Head and Neck
PubMed: 24491903
DOI: 10.5604/17322693.1088044 -
Proceedings of the National Academy of... Jul 2023Antibiotics are among the most used weapons in fighting microbial infections and have greatly improved the quality of human life. However, bacteria can eventually evolve...
Antibiotics are among the most used weapons in fighting microbial infections and have greatly improved the quality of human life. However, bacteria can eventually evolve to exhibit antibiotic resistance to almost all prescribed antibiotic drugs. Photodynamic therapy (PDT) develops little antibiotic resistance and has become a promising strategy in fighting bacterial infection. To augment the killing effect of PDT, the conventional strategy is introducing excess ROS in various ways, such as applying high light doses, high photosensitizer concentrations, and exogenous oxygen. In this study, we report a metallacage-based PDT strategy that minimizes the use of ROS by jointly using gallium-metal organic framework rods to inhibit the production of bacterial endogenous NO, amplify ROS stress, and enhance the killing effect. The augmented bactericidal effect was demonstrated both in vitro and in vivo. This proposed enhanced PDT strategy will provide a new option for bacterial ablation.
Topics: Humans; Photochemotherapy; Reactive Oxygen Species; Photosensitizing Agents; Anti-Bacterial Agents; Bacteria
PubMed: 37428928
DOI: 10.1073/pnas.2218973120 -
Pharmacological Research May 2024Cancer, with its diversity, heterogeneity, and complexity, is a significant contributor to global morbidity, disability, and mortality, highlighting the necessity for... (Review)
Review
Cancer, with its diversity, heterogeneity, and complexity, is a significant contributor to global morbidity, disability, and mortality, highlighting the necessity for transformative treatment approaches. Photodynamic therapy (PDT) has aroused continuous interest as a viable alternative to conventional cancer treatments that encounter drug resistance. Nanotechnology has brought new advances in medicine and has shown great potential in drug delivery and cancer treatment. For precise and efficient therapeutic utilization of such a tumor therapeutic approach with high spatiotemporal selectivity and minimal invasiveness, the carrier-free noncovalent nanoparticles (NPs) based on chemo-photodynamic combination therapy is essential. Utilizing natural products as the foundation for nanodrug development offers unparalleled advantages, including exceptional pharmacological activity, easy functionalization/modification, and well biocompatibility. The natural-product-based, carrier-free, noncovalent NPs revealed excellent synergistic anticancer activity in comparison with free photosensitizers and free bioactive natural products, representing an alternative and favorable combination therapeutic avenue to improve therapeutic efficacy. Herein, a comprehensive summary of current strategies and representative application examples of carrier-free noncovalent NPs in the past decade based on natural products (such as paclitaxel, 10-hydroxycamptothecin, doxorubicin, etoposide, combretastatin A4, epigallocatechin gallate, and curcumin) for tumor chemo-photodynamic combination therapy. We highlight the insightful design and synthesis of the smart carrier-free NPs that aim to enhance PDT efficacy. Meanwhile, we discuss the future challenges and potential opportunities associated with these NPs to provide new enlightenment, spur innovative ideas, and facilitate PDT-mediated clinical transformation.
Topics: Humans; Photochemotherapy; Animals; Neoplasms; Nanoparticles; Biological Products; Antineoplastic Agents; Photosensitizing Agents
PubMed: 38521285
DOI: 10.1016/j.phrs.2024.107150 -
International Journal of Molecular... Aug 2015Photodynamic therapy (PDT) is a clinical modality used to treat cancer and infectious diseases. The main agent is the photosensitizer (PS), which is excited by light and... (Review)
Review
Photodynamic therapy (PDT) is a clinical modality used to treat cancer and infectious diseases. The main agent is the photosensitizer (PS), which is excited by light and converted to a triplet excited state. This latter species leads to the formation of singlet oxygen and radicals that oxidize biomolecules. The main motivation for this review is to suggest alternatives for achieving high-efficiency PDT protocols, by taking advantage of knowledge on the chemical and biological processes taking place during and after photosensitization. We defend that in order to obtain specific mechanisms of cell death and maximize PDT efficiency, PSes should oxidize specific molecular targets. We consider the role of subcellular localization, how PS photochemistry and photophysics can change according to its nanoenvironment, and how can all these trigger specific cell death mechanisms. We propose that in order to develop PSes that will cause a breakthrough enhancement in the efficiency of PDT, researchers should first consider tissue and intracellular localization, instead of trying to maximize singlet oxygen quantum yields in in vitro tests. In addition to this, we also indicate many open questions and challenges remaining in this field, hoping to encourage future research.
Topics: Animals; Cell Death; Humans; Oxidation-Reduction; Photochemistry; Photochemotherapy; Photosensitizing Agents
PubMed: 26334268
DOI: 10.3390/ijms160920523