Navegando por Autor "Ivanova, Natalia"
Agora exibindo 1 - 2 de 2
Resultados por página
Opções de Ordenação
Item Effects of the phototherapy (blue light) on the heart inflammatory response induced by Trypanosoma cruzi in mice.(2019) Ivanova, Natalia; Silva, André Talvani Pedrosa da; Bianchi, Rodrigo Fernando; Silva, André Talvani Pedrosa da; Silva, Maria Cláudia da; Perucci, Luiza Oliveira; Rezende, Simone AparecidaThe Trypanosoma cruz, is the causative agent of Chagas disease. According to WHO (2019), currently about 7 million people are infected with T. cruzi mainly in Latin America. Despite the fact that pharmaceutical industry releases various new drugs every year, Chagas disease has only two standard substances for treatment, Benznidazole and Nifurtimox, which were recognized as chemotherapy. However, at the same time these medicines have many side effects and are inefficient in chronic phase. Nowadays the blue light is commonly used in medicine practice around the world. It was proved its antimicrobial characteristics. In the current study, were evaluated the influence of the blue light on the inflammatory parameters in C57BL6 mice (in vivo) infected with T. cruzi and as well as development of parasites in vitro. For in vitro experiment we used Y and CL strain of T. cruzi. The blue light was applied (with the pic 460 nm and 80 μW/cm2) on parasite cell culture for 5 days, 6h per day, at room temperature. The parasites were counted in 10 μL every day using the Neubauer Chamber. Treatment with the blue light led to the reduction of replication of T. cruzi in vitro. Data showed 50% reduction of parasites in experiment after 5 days of exposition, in comparison to control. For in vivo experiment was used Y strain of T. cruzi. 40 animals were separated into 4 groups: non-infected + conventional light, non-infected + blue light, infected + conventional light, and infected + blue light. Blue light was applied (with the pic 460 nm and 7 μW/cm2) for 9 days, 12 h per day. Was found that phototherapy with blue light reduce quantity of parasites circulating in the blood of animals comparing with conventional light. Blue light altered the plasma pattern of the inflammatory and regulatory mediators. After morphological analysis, was found that both infected groups exhibited parasitized cardiomyocytes with intense myocarditis with predominance of pericellular and perivascular mononuclear inflammatory infiltrate. Phototherapy with blue light reduced the quantity amastigote in the nests in cardiac tissue. These data can be used for the development of a new way of treatment for Chagas disease in the future.Item New insights into blue light phototherapy in experimental Trypanosoma cruzi infection.(2021) Ivanova, Natalia; Leite, Ana Luísa Junqueira; Vieira, Marcel Barbosa; Silva, Otto Henrique Cezar e; Mota, Ludmilla Walter Reis; Costa, Guilherme de Paula; Azevedo, Cristiano Schetini de; Auharek, Sarah Alves; Novaes, Romulo Dias; Pinto, Kelerson Mauro de Castro; Bianchi, Rodrigo Fernando; Silva, André Talvani Pedrosa daThe search for an effective etiologic treatment to eliminate Trypanosoma cruzi, the causative agent of Chagas disease, has continued for decades and yielded controversial results. In the 1970s, nifurtimox and benznidazole were introduced for clinical assessment, but factors such as parasite resistance, high cellular toxicity, and efficacy in acute and chronic phases of the infection have been debated even today. This study proposes an innovative strategy to support the controlling of the T. cruzi using blue light phototherapy or blue light-emitting diode (LED) intervention. In in vitro assays, axenic cultures of Y and CL strains of T. cruzi were exposed to 460 nm and 40 μW/cm2 of blue light for 5 days (6 h/day), and parasite replication was evaluated daily. For in vivo experiments, C57BL6 mice were infected with the Y strain of T. cruzi and exposed to 460 nm and 7 μW/cm2 of blue light for 9 days (12 h/day). Parasite count in the blood and cardiac tissue was determined, and plasma interleukin (IL-6), tumoral necrosis factor (TNF), chemokine ligand 2 (CCL2), and IL-10 levels and the morphometry of the cardiac tissue were evaluated. Blue light induced a 50% reduction in T. cruzi (epimastigote forms) replication in vitro after 5 days of exposure. This blue light-mediated parasite control was also observed by the T. cruzi reduction in the blood (trypomastigote forms) and in the cardiac tissue (parasite DNA and amastigote nests) of infected mice. Phototherapy reduced plasma IL-6, TNF and IL-10, but not CCL2, levels in infected animals. This non-chemical therapy reduced the volume density of the heart stroma in the cardiac connective tissue but did not ameliorate the mouse myocarditis, maintaining a predominance of pericellular and perivascular mononuclear inflammatory infiltration with an increase in polymorphonuclear cells. Together, these data highlight, for the first time, the use of blue light therapy to control circulating and tissue forms of T. cruzi. Further investigation would demonstrate the application of this promising and potential complementary strategy for the treatment of Chagas disease.