DEFAR - Departamento de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530

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Resultados da Pesquisa

Agora exibindo 1 - 4 de 4
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    Vaccination with formulation of nanoparticles loaded with Leishmania amazonensis antigens confers protection against experimental visceral leishmaniasis in hamster.
    (2023) Cabrera González, Marco Antonio; Gonçalves, Ana Alice Maia; Ottino, Jennifer; Leite, Jaqueline Costa; Resende, Lucilene Aparecida; Melo Júnior, Otoni Alves de Oliveira; Silveira, Patricia; Cardoso, Mariana Santos; Fujiwara, Ricardo Toshio; Bueno, Lilian Lacerda; Santos, Renato Lima; Carvalho, Tatiane Furtado de; Garcia, Giani Martins; Paes, Paulo Ricardo de Oliveira; Galdino, Alexsandro Sobreira; Chávez Fumagalli, Miguel Angel; Melo, Marilia Martins; Lemos, Denise da Silveira; Martins Filho, Olindo Assis; Dutra, Walderez Ornelas; Mosqueira, Vanessa Carla Furtado; Giunchetti, Rodolfo Cordeiro
    Visceral leishmaniasis (VL) is a fatal disease caused by the protozoa Leishmania infantum for which dogs are the main reservoirs. A vaccine against canine visceral leishmaniasis (CVL) could be an important tool in the control of human and CVL by reducing the infection pressure of L. infantum. Despite the CVL vaccine available on the market, the Brazilian Ministry of Health did not implement the use of it in their control programs. In this sense, there is an urgent need to develop more efficient vaccines. In this study, the association between two polymeric nanoformulations, (poly (D, L-lactic) acid (PLA) polymer) loading Leishmania amazonensis antigens, was evaluated as a potential immunobiological agent against VL using golden hamsters as an experimental model. The results indicated that no significant adverse reactions were observed in animals vaccinated with LAPSmP. LAPSmP presented similar levels of total anti-Leishmania IgG as compared to LAPSmG. The LAPSmP and LAPSmG groups showed an intense reduction in liver and spleen parasitic load by qPCR. The LAPSmP and LAPSmG vaccines showed exceptional results, indicating that they may be promising candidates as a VL vaccine.
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    Nanoformulations with Leishmania braziliensis antigens triggered controlled parasite burden in vaccinated golden hamster (Mesocricetus auratus) against visceral leishmaniasis.
    (2022) Ottino, Jennifer; Leite, Jaqueline Costa; Melo Júnior, Otoni Alves de Oliveira; Cabrera González, Marco Antonio; Carvalho, Tatiane Furtado de; Garcia, Giani Martins; Batista, Maurício Azevedo; Silveira, Patrícia; Cardoso, Mariana Santos; Bueno, Lilian Lacerda; Fujiwara, Ricardo Toshio; Santos, Renato Lima; Paes, Paulo Ricardo de Oliveira; Lemos, Denise da Silveira; Martins Filho, Olindo Assis; Galdino, Alexsandro Sobreira; Chávez Fumagalli, Miguel Angel; Dutra, Walderez Ornelas; Mosqueira, Vanessa Carla Furtado; Giunchetti, Rodolfo Cordeiro
    Leishmaniasis is a widespread vector-borne disease in Brazil, with Leishmania (Leishmania) infantum as the primary etiological agent of visceral leishmaniasis (VL). Dogs are considered the main reservoir of this parasite, whose treatment in Brazil is restricted to the use of veterinary medicines, which do not promote a parasitological cure. Therefore, efficient vaccine development is the best approach to Canine Visceral Leishmaniasis (CVL) control. With this in mind, this study used hamsters (Mesocricetus auratus) as an experimental model in an anti-Leishmania preclinical vaccine trial to evaluate the safety, antigenicity, humoral response, and effects on tissue parasite load. Two novel formulations of nanoparticles made from poly(D, L-lactic) acid (PLA) polymer loading Leishmania braziliensis crude antigen (LB) exhibiting two different particle sizes were utilized: LBPSmG (570 nm) and LBPSmP (388 nm). The results showed that the nanoparticles were safe and harmless to hamsters and were antigenic with the induction in LBSap, LBPSmG, and LBPSmG groups of total anti-Leishmania IgG antibodies 30 days after challenge, which persists 200 days in LBSap and LBPSmP. At the same time, a less pronounced hepatosplenomegaly in LBSap, LBPSmG, and LBPSmP was found when compared to control groups, as well as a less pronounced inflammatory infiltrate and granuloma formation in the spleen. Furthermore, significant reductions of 84%, 81%, and 90% were observed in spleen parasite burden accessed by qPCR in the LBSap, LBPSmG, and LBPSmP groups, respectively. In this way, LBSap, LBPSmG, and LBPSmP formulations showed better results in vaccinated and L. infantum-challenged animals in further reducing parasitic load in the spleen and attenuating lesions in liver and splenic tissues. This results in safe, harmless nanoformulation vaccines with significant immunogenic and infection control potential. In addition, animals vaccinated with LBPSmP had an overall reduction in parasite burden in the spleen, indicating that a smaller nanoparticle could be more efficient in targeting antigen-presenting cells.
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    A chloroquinoline derivate presents effective in vitro and in vivo antileishmanial activity against Leishmania species that cause tegumentary and visceral leishmaniasis.
    (2019) Sousa, Jéssica Karine Távora de; Antinarelli, Luciana Maria Ribeiro; Mendonça, Débora Vasconcelos Costa; Lage, Daniela Pagliara; Tavares, Grasiele de Sousa Vieira; Dias, Daniel Silva; Ribeiro, Patrícia Aparecida Fernandes; Ribeiro, Fernanda Ludolf; Coelho, Vinicio Tadeu da Silva; Silva, João Augusto Oliveira da; Melo, Luísa Helena Perin de; Oliveira, Bianka A.; Alvarenga, Denis Fernando; Chávez Fumagalli, Miguel Angel; Brandão, Geraldo Célio; Vandack, Nobre; Pereira, Guilherme Rocha; Coimbra, Elaine Soares; Coelho, Eduardo Antônio Ferraz
    The identification of new therapeutics to treat leishmaniasis is desirable, since available drugs are toxic and present high cost and/or poor availability. Therefore, the discovery of safer, more effective and selective pharmaceutical options is of utmost importance. Efforts towards the development of new candidates based on molecule analogs with known biological functions have been an interesting and cost-effective strategy. In this context, quinoline derivatives have proven to be effective biological activities against distinct diseases. In the present study, a new chloroquinoline derivate, AM1009, was in vitro tested against two Leishmania species that cause leishmaniasis. The present study analyzed the necessary inhibitory concentration to preclude 50% of the Leishmania promastigotes and axenic amastigotes (EC50 value), as well as the inhibitory concentrations to preclude 50% of the murine macrophages and human red blood cells (CC50 and RBC50 values, respectively). In addition, the treatment of infected macrophages and the inhibition of infection using pre-treated parasites were also investigated, as was the mechanism of action of the molecule in L. amazonensis. To investigate the in vivo therapeutic effect, BALB/c mice were infected with L. amazonensis and later treated with AM1009. Parasitological and immunological parameters were also evaluated. Clioquinol, a known antileishmanial quinoline derivate, and amphotericin B (AmpB), were used as molecule and drug controls, respectively. Results in both in vitro and in vivo experiments showed a better and more selective action of AM1009 to kill the in vitro parasites, as well as in treating infected mice, when compared to results obtained using clioquinol or AmpB. AM1009-treated animals presented significantly lower average lesion diameter and parasite burden in the infected tissue and organs evaluated in this study, as well as a more polarized antileishmanial Th1 immune response and low renal and hepatic toxicity. This result suggests that AM1009 should be considered a possible therapeutic target to be evaluated in future studies for treatment against leishmaniasis.
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    Poloxamer 407 (Pluronic® F127)-based polymeric micelles for amphotericin B : in vitro biological activity, toxicity and in vivo therapeutic efficacy against murine tegumentary leishmaniasis.
    (2016) Mendonça, Débora Vasconcelos Costa; Lage, Letícia Martins dos Reis; Lage, Daniela Pagliara; Chávez Fumagalli, Miguel Angel; Ribeiro, Fernanda Ludolf; Roatt, Bruno Mendes; Souza, Daniel Menezes; Faraco, André Augusto Gomes; Castilho, Rachel Oliveira; Tavares, Carlos Alberto Pereira; Barichello, José Mario; Duarte, Mariana Costa; Coelho, Eduardo Antônio Ferraz
    In the present study, a Poloxamer 407-based amphotericin B (AmpB)-containing polymeric micelles system (AmpB/M) was employed in the treatment of Leishmania amazonensis-infected BALB/c mice. Initially, the in vitro antileishmanial activity (IC50 value) of AmpB/M and B-AmpB/M (empty micelles) against stationary promastigotes and amastigotes-like forms of the parasites was determined, and results were of 1.83 ± 0.4 and 22.1 ± 0.7 mM, respectively, for the promastigotes, and of 2.27 ± 0.5 and 33.98 ± 2.6 mM, respectively, for the amastigotes-like. The cytotoxic concentration (CC50) values of these products were also evaluated, and we found the results of 119.5 ± 9.6 and 134.7 ± 10.3 mM, respectively. With these values, the selectivity index (SI) was calculated and results were of 65.3 and 5.4, respectively, for the promastigotes, and of 59.3 and 3.96, respectively, for the amastigotes-like of the parasites. Free AmpB showed IC50 values of 1.2 ± 0.3 and 2.5 ± 0.5 mM for the promastigotes and amastigotes-like, respectively, whereas the CC50 value was of 9.5 ± 0.4 mM. The SI values of this drug were of 7.9 and 3.8, respectively, for the promastigote and amastigote-like stages of the parasites. After, animals were infected and received saline or were treated subcutaneously with free AmpB, AmpB/M or B-AmpB/M. In the results, free AmpB-treated and infected mice showed reductions in their body weight, which were associated with hepatic and renal damage; however, no organic alteration was observed in the AmpB/Mtreated animals. In addition, these animals showed significant reductions in their lesion average size and in the parasite burden in all evaluated infected tissue and organs, when compared to the other groups; as well as significantly higher levels of antileishmanial IFN-g, IL-12, GM-CSF and nitrite, which were associated with low production of IL-4, IL-10 and IgG1 isotype antibodies. In conclusion, this AmpB/M system could be considered as an alternative for future studies in the treatment of tegumentary leishmaniasis.