Liposomal photosensitizers : potential platforms for anticancer photodynamic therapy

Photodynamic therapy is a well-established and clinically approved treatment for several types of cancer. Antineoplastic photodynamic therapy is based on photosensitizers, i.e., drugs that absorb photons translating light energy into a chemical potential that damages tumor tissues. Despite the encouraging clinical results with the approved photosensitizers available today, the prolonged skin phototoxicity, poor selectivity for diseased tissues, hydrophobic nature, and extended retention in the host organism shown by these drugs have stimulated researchers to develop new formulations for photodynamic therapy. In this context, due to their amphiphilic characteristic (compatibility with both hydrophobic and hydrophilic substances), liposomes have proven to be suitable carriers for photosensitizers, improving the photophysical properties of the photosensitizers. Moreover, as nanostructured drug delivery systems, liposomes improve the efficiency and safety of antineoplastic photodynamic therapy, mainly by the classical phenomenon of extended permeation and retention. Therefore, the association of photosensitizers with liposomes has been extensively studied. In this review, both current knowledge and future perspectives on liposomal carriers for antineoplastic photodynamic therapy are critically discussed

The pequi pulp oil (Caryocar brasiliense Camb.) provides protection against aging-related anemia, inflammation and oxidative stress in Swiss mice, especially in females

Continued exposure to reactive oxygen species and inflammation are the rationale behind aging theories and associated diseases. Scientific evidence corroborates the ethnomedicinal use of the oil of pequi (Caryocar brasiliense Camb.), a typical Brazilian Cerrado fruit, against oxidative damage to biomolecules and inflammation. We aimed to investigate in vivo the antioxidant and anti-inflammatory effects of pequi oil on hemogram and DNA damage in healthy young adult and older middle-aged Swiss mice of both genders. Animals, aged 6-7 and 11-12 months, were orally treated for 15 days with pequi oil at 30 mg/day. Blood samples were used for hemogram and comet assay, and bone marrow for micronucleus test. Female controls of 11-12 months had significantly lower haemoglobin and hematocrit than those of 6-7 months. Treatment with pequi oil improved this state, removing the differences. Pequi oil had no genotoxic or clastogenic effects and significantly increased lymphocytes and decreased neutrophils+monocytes in females of 11-12 months, removing the significant differences observed between controls of 6-7 and 11-12 months. The results suggest that dietary supplementation with pequi oil could protect against anemia, inflammation and oxidative stress related to aging, helping to prevent aging-related chronic degenerative diseases, mainly for females

Photodynamic Therapy, a new approach in the treatment of oral cancer

RESUMEN La incidencia del cáncer de cabeza y cuello es aproximadamente 640.000 casos nuevos por año. El cáncer oral representa un tercio de todos los cánceres y es el octavo más diagnosticado en hombres. Los tratamientos más usados para estos tumores son la cirugía, radioterapia, quimioterapia, o una combinación de estas modalidades terapéuticas. Debido al gran deterioro estructural, funcional y estético que causan los tratamientos convencionales, muchos estudios buscan nuevos métodos para remplazar o asistir el tratamiento del cáncer oral. La terapia fotodinámica (PDT) es una nueva modalidad promisoria en el tratamiento del cáncer que apenas está siendo usada clínicamente. Este artículo describe el uso de PDT como una alternativa para el tratamiento del cáncer oral. Salud UIS 2010; 42: 167-174 Palabras clave: Terapia fotodinámica, cáncer oral, tratamiento       ABSTRACT The worldwide incidence of head and neck cancer is, approximately, 640,000 new cases per year. Oral cancer accounts for one third of all cancers and it is the eighth most diagnosed in men. The most used treatments for these tumors are surgery, radiotherapy, chemotherapy, or a combination of these therapeutic modalities. Due to the large structural, functional and aesthetic impairment that conventional treatments cause, many studies seek new methods to replace or to assist the treatment of oral cancer. Photodynamic therapy (PDT) is a promising new modality of cancer treatment that is already being used clinically. This article describes the use of PDT as an alternative for the treatment of oral cancer. Salud UIS 2010; 42: 167-174 Keywords: Photodynamic therapy, oral cancer, treatmen

Photodynamic Therapy, a new approach in the treatment of oral cancer

RESUMEN La incidencia del cáncer de cabeza y cuello es aproximadamente 640.000 casos nuevos por año. El cáncer oral representa un tercio de todos los cánceres y es el octavo más diagnosticado en hombres. Los tratamientos más usados para estos tumores son la cirugía, radioterapia, quimioterapia, o una combinación de estas modalidades terapéuticas. Debido al gran deterioro estructural, funcional y estético que causan los tratamientos convencionales, muchos estudios buscan nuevos métodos para remplazar o asistir el tratamiento del cáncer oral. La terapia fotodinámica (PDT) es una nueva modalidad promisoria en el tratamiento del cáncer que apenas está siendo usada clínicamente. Este artículo describe el uso de PDT como una alternativa para el tratamiento del cáncer oral. Salud UIS 2010; 42: 167-174 Palabras clave: Terapia fotodinámica, cáncer oral, tratamiento       ABSTRACT The worldwide incidence of head and neck cancer is, approximately, 640,000 new cases per year. Oral cancer accounts for one third of all cancers and it is the eighth most diagnosed in men. The most used treatments for these tumors are surgery, radiotherapy, chemotherapy, or a combination of these therapeutic modalities. Due to the large structural, functional and aesthetic impairment that conventional treatments cause, many studies seek new methods to replace or to assist the treatment of oral cancer. Photodynamic therapy (PDT) is a promising new modality of cancer treatment that is already being used clinically. This article describes the use of PDT as an alternative for the treatment of oral cancer. Salud UIS 2010; 42: 167-174 Keywords: Photodynamic therapy, oral cancer, treatmen

An overview on immunogenic cell death in cancer biology and therapy

Immunogenic cell death (ICD) is a modality of regulated cell death that is sufficient to promote an adaptive immune response against antigens of the dying cell in an immunocompetent host. An important characteristic of ICD is the release and exposure of damage-associated molecular patterns, which are potent endogenous immune adjuvants. As the induction of ICD can be achieved with conventional cytotoxic agents, it represents a potential approach for the immunotherapy of cancer. Here, different aspects of ICD in cancer biology and treatment are reviewed

Oral delivery of fish oil in oil-in-water nanoemulsion : development, colloidal stability and modulatory effect on in vivo inflammatory induction in mice

To improve the oral absorption of fish oil and test its anti-inflammatory effect, a fish oil nanoemulsion was developed using cis-4,7,10,13,16,19-docosahexaenoic fatty acid as a biomarker for oral administration. The colloidal stability tests of the fish oil nanoemulsion showed an average size of 155.44 nm ± 6.46 (4 °C); 163.04 nm ± 9.97 (25 °C) and polydispersity index 0.22 ± 0.02 (4 °C), 0.21 ± 0.02 (25 °C), indicating systems with low polydispersity and stable droplets. The fish oil nanoemulsion did not alter the cell viability of the RAW 264.7 macrophages and, at a concentration of 0.024 mg/mL, was kinetically incorporated into the cells after 18 h of contact. The nanoemulsion was maintained in the gastrointestinal region for a significantly shorter period of time (p ≤ 0.05) compared to the intake of fish oil in free form. Inflammatory tests demonstrated that nanoemulsion and fish oil showed less (p ≤ 0.05) neutrophil infiltration after 24h of sepsis induction and there was a significant reduction (p ≤ 0.05) in the volume of paw edema in female adult Balb/c mice who received the nanoemulsion diet compared to the other experimental groups (control, formalin, fish oil and sunflower oil). These results indicate that the fish oil nanoemulsion was significantly effective in the dietary conditions tested here, presenting satisfactory responses in the modulation of inflammatory disorders, demonstrating interesting and beneficial nutraceutical effects

Avaliação da aplicação da terapia fotodinâmica mediada pela alumínio-cloro-ftalocianina em formulação lipossomal sobre o câncer bucal em modelos experimentais in vivo e in vitro

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Medicina, 2008.O tratamento atual para o câncer de boca é feito através de cirurgia, radioterapia, quimioterapia ou uma associação destas modalidades terapêuticas. Por promoverem graves efeitos adversos aos pacientes, constantes esforços são tomados no desenvolvimento de novos protocolos terapêuticos que possam substituir ou auxiliar os tratamentos convencionais. A Terapia Fotodinâmica (TFD) é uma alternativa que tem sido utilizada clinicamente com sucesso para o tratamento de tumores superficiais com efeitos colaterais mínimos. Esta dissertação teve como objetivo a avaliação da aplicação da TFD mediada pela Alumínio-Cloro-Ftalocianina (AlClFt) em formulação lipossomal sobre o Câncer de Boca em modelos experimentais in vitro e in vivo. Experimentos in vitro utilizando células derivadas de carcinoma epidermóide bucal humano (linhagem OSCC) demonstraram alta eficiência daTFD na destruição destas células tumorais. Para os experimentos in vivo, foram induzidos três diferentes modelos experimentais: (1) indução química pela aplicação tópica do carcinógeno 4-NQO na língua de camundongos Swiss; (2) injeção das células OSCC no subcutâneo dorsal de camundongos nude-Balb/c; (3) injeção de células derivadas do tumor de Ehrlich na lingua de camundongos Swiss. A análise histológica dos três modelos experimentais monstrou que a TFD atua na destruiçao tumoral pela (1) indução de citotoxidade direta às células tumorais e (2) pela promoção de efeitos lesivos nos vasos do microambiente neoplásico, que culminaria no desenvolvimento de necrose tumoral por hipóxia. Os resultados apresentados indicam excelentes perspectivas para a utilização da TFD mediada pela AlClFt em ensaios clínicos posteriores. _______________________________________________________________________________________ ABSTRACTSurgery, chemotherapy, radiotherapy or a combination of these three methods are common treatments for oral cancer. Although these protocols have demonstrated some effectiveness in oral cancer therapy, they can promote a series of side effects for patients during treatment. Alternatively for these traditional treatments, Photodynamic Therapy (PDT) has been used clinically for oral cancer and precancerous lesions treatment. The objective of this study was the evaluation of PDT mediated by Aluminum-Chlorine-Phtalocyanine (AlClPc) in different in vitro and in vivo oral cancer models. In vitro experiments showed PDT as a high citotoxic treatment in oral squamous cell carcinoma cell line (OSCC). As animal model, three different tumor were induced: (1) 4-NQO carcinogenesis induction in Swiss mice tongue; (2) injection of OSCC cell line in dorsal subcutaneous Balb/c-nude mice; (3) Ehrlich tumor cell injection in Swiss mice tongue. Histopathological analyses showed that PDT produce a (1) direct citotoxicity in tumor cells and (2) vascular damage that could produces hypoxia areas in tumor microambient. Taken together, the results indicated that PDT mediated by AlClPt has excellent perspectives to be applied in future clinical trials