LUIZ FELIPE DOMINGUES PASSERO
Projetos de Pesquisa
Unidades Organizacionais
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina
9 resultados
Resultados de Busca
Agora exibindo 1 - 9 de 9
- Salivary gland homogenates from wild-caught sand flies Lutzomyia flaviscutellata and Lutzomyia (Psychodopygus) complexus showed inhibitory effects on Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis infection in BALB/c mice(2014) FRANCESQUINI, Fernanda C.; SILVEIRA, Fernando T.; PASSERO, Luiz Felipe D.; TOMOKANE, Thaise Y.; CARVALHO, Ana Kely; CORBETT, Carlos Eduardo P.; LAURENTI, Marcia D.During the natural transmission of Leishmania parasites, the infected sand fly female regurgitates promastigotes into the host's skin together with its saliva. It has been reported that vector saliva contains immunomodulatory molecules that facilitate the establishment of infection. Thus, the main objective of this study was to evaluate the specificity of Lutzomyia (Lu.) flaviscutellata and Lu.(Psychodopygus) complexus salivas on the infectivity of Leishmania (L.) (Leishmania) amazonensis and L.(Viannia) braziliensis, respectively. BALB/c mice were inoculated into the skin of hind footpad with L.(L.) amazonensis and L.(V.) braziliensis promastigotes in the absence or presence of Lu.flaviscutellata and Lu.(P.) complexus salivary gland homogenates (SGHs). The evolution of the infection was evaluated by lesion size, histopathological analysis and determination of the parasite load in the skin biopsies collected from the site of infection at 4 and 8weeks PI. The lesion size and the parasite load of both groups of mice infected in the presence of SGHs were smaller than the control groups. The histopathological features showed that the inflammatory reaction was less prominent in the groups of mice infected in the presence of both SGHs when compared to the control group. The results showed that the presence of SGHs of Lu.flaviscutellata and Lu.(P.) complexus led to induction of processes that were disadvantageous to parasite establishment during infection by L.(L.) amazonensis and L.(V.) braziliensis. An inhibitory effect on Leishmania infection could be observed in both groups inoculated with SGHs, especially when the SGH from Lu.(P.) complexus was used.
article 24 Citação(ões) na Scopus Chemical Composition and in vitro Cytotoxic and Antileishmanial Activities of Extract and Essential Oil from Leaves of Piper cernuum(2015) CAPELLO, Tabata M.; MARTINS, Euder G. A.; FARIAS, Camyla F. de; FIGUEIREDO, Carlos R.; MATSUO, Alisson L.; PASSERO, Luiz Felipe D.; OLIVEIRA-SILVA, Diogo; SARTORELLI, Patricia; LAGO, Joao Henrique G.Fractionation of the MeOH extract from leaves of Piper cernuum Veil. (Piperaceae) afforded six phenylpropanoid derivatives: 3',4'-dimethoxydihydrocinnamic acid (1), piplaroxide (2), methyl 4'-hydroxy-3',5'-dimethoxy cinnamate (3), 3',4',5'-trimethoxydihydrocinnamic acid (3), dihydropiplartine (5), and piplartine (6). The structures of isolated metabolites were characterized by NMR and MS spectral data analysis. The chemical composition of essential oil from the leaves was determined using GC/LREIMS followed by the determination of Kovats indexes. This procedure allowed the identification of nineteen terpenoids, with beta-elemene (7), bicyclogermacrene (8), germacrene D (9), and (E)-caryophyllene (10) as the main compounds. Compounds 1 and 3-6 displayed no in vitro cytotoxicity against cancer cell lineages B16F10-Nex2, U87, HeLa, HL-60, HCT, and A2058 while 2 showed moderate activity against B16F10-Nex2 and HL-60 lines. Otherwise, compounds 7-10 displayed high cytotoxic activity. Evaluation against non-tumorigenic HFF cells indicated a reduced selectivity of compounds 7-10 to tumoral cells. No antileishmanial activity on macrophages infected with L. (L.) amazonensis was found for the crude MeOH extract and compounds 1-6. The crude essential oil and compounds 7-10 reduced parasitism and eliminated the majority of infected and non-infected cells at 50 mu g/mL.- Antimicrobial Activity of Oleanolic and Ursolic Acids: An Update(2015) JESUS, Jessica A.; LAGO, Joao Henrique G.; LAURENTI, Marcia D.; YAMAMOTO, Eduardo S.; PASSERO, Luiz Felipe D.Triterpenoids are the most representative group of phytochemicals, as they comprise more than 20,000 recognized molecules. These compounds are biosynthesized in plants via squalene cyclization, a C-30 hydrocarbon that is considered to be the precursor of all steroids. Due to their low hydrophilicity, triterpenes were considered to be inactive for a long period of time; however, evidence regarding their wide range of pharmacological activities is emerging, and elegant studies have highlighted these activities. Several triterpenic skeletons have been described, including some that have presented with pentacyclic features, such as oleanolic and ursolic acids. These compounds have displayed incontestable biological activity, such as antibacterial, antiviral, and antiprotozoal effects, which were not included in a single review until now. Thus, the present review investigates the potential use of these triterpenes against human pathogens, including their mechanisms of action, via in vivo studies, and the future perspectives about the use of compounds for human or even animal health are also discussed.
- New insights into neutrophil and Leishmania infantum in vitro immune interactions(2015) MARQUES, Claudia S.; PASSERO, Luiz Felipe D.; VALE-GATO, Ines; RODRIGUES, Armanda; RODRIGUES, Olivia Roos; MARTINS, Catarina; CORREIA, Ivone; TOMAS, Ana M.; ALEXANDRE-PIRES, Graca; FERRONHA, M. Helena; SANTOS-GOMES, Gabriela M.The interaction between polymorphonuclear leukocytes (PMN) or neutrophils and Leishmania became an interesting focus of research, since PMN turn out to be essential cells in transiently hosting the parasites. This study aims to evaluate whether L. infantum, the etiological agent of zoonotic visceral leishmaniasis, influences the in vitro functional activity of murine neutrophils. Phagocytosis, chemotaxis, oxidative burst, degranulation and apoptosis assays were performed. Cytokines, chemokines and toll-like receptors gene expression were evaluated by Real-time PCR. Results indicate that some of the innate features of PMN immunity were activated when in contact with L. infantum. However, parasites might negatively interfere with PMN defense mechanisms compromising the link between innate and acquired immunity. This work provides additional insights on the inflammatory immune interactions between neutrophils and L. infantum highlighting the role of PMN in Leishmania infection.
- Proteins of Leishmania (Viannia) shawi confer protection associated with Th1 immune response and memory generation(2012) PASSERO, Luiz Felipe D.; CARVALHO, Ana Kely; BORDON, Maria L. A. C.; BONFIM-MELO, Alexis; CARVALHO, Karina; KALLAS, Esper G.; SANTOS, Bianca B. A.; TOYAMA, Marcos H.; PAES-LEME, Adriana; CORBETT, Carlos E. P.; LAURENTI, Marcia D.Background: Leishmania (Viannia) shawi parasite was first characterized in 1989. Recently the protective effects of soluble leishmanial antigen (SLA) from L. (V.) shawi promastigotes were demonstrated using BALB/c mice, the susceptibility model for this parasite. In order to identify protective fractions, SLA was fractionated by reverse phase HPLC and five antigenic fractions were obtained. Methods: F1 fraction was purified from L. (V.) shawi parasite extract by reverse phase HPLC. BALB/c mice were immunized once a week for two consecutive weeks by subcutaneous routes in the rump, using 25 mu g of F1. After 1 and 16 weeks of last immunization, groups were challenged in the footpad with L. (V.) shawi promastigotes. After 2 months, those same mice were sacrificed and parasite burden, cellular and humoral immune responses were evaluated. Results: The F1 fraction induced a high degree of protection associated with an increase in IFN-gamma, a decrease in IL-4, increased cell proliferation and activation of CD8(+)T lymphocytes. Long-term protection was acquired in F1-immunized mice, associated with increased CD4(+) central memory T lymphocytes and activation of both CD4+ and CD8(+) T cells. In addition, F1-immunized groups showed an increase in IgG2a levels. Conclusions: The inductor capability of antigens to generate memory lymphocytes that can proliferate and secrete beneficial cytokines upon infection could be an important factor in the development of vaccine candidates against American Tegumentary Leishmaniasis.
- Anti-leishmanial effects of purified compounds from aerial parts of Baccharis uncinella C. DC. (Asteraceae)(2011) PASSERO, Luiz Felipe D.; BONFIM-MELO, Alexis; CORBETT, Carlos Eduardo P.; LAURENTI, Marcia D.; TOYAMA, Marcos H.; TOYAMA, Daniela O. de; ROMOFF, Paulete; FAVERO, Oriana A.; GRECCO, Simone S. dos; ZALEWSKY, Cynthia A.; LAGO, Joo Henrique G.Species of Baccharis exhibit antibiotic, antiseptic, wound-healing, and anti-protozoal properties, and have been used in the traditional medicine of South America for the treatment of several diseases. In the present work, the fractionation of EtOH extract from aerial parts of Baccharis uncinella indicated that the isolated compounds caffeic acid and pectolinaringenin showed inhibitory activity against Leishmania (L.) amazonensis and Leishmania (V.) braziliensis promastigotes, respectively. Moreover, amastigote forms of both species were highly sensible to the fraction composed by oleanolic + ursolic acids and pectolinaringenin. Caffeic acid also inhibited amastigote forms of L. (L.) amazonensis, but this effect was weak in L. (V.) braziliensis amastigotes. The treatment of infected macrophages with these compounds did not alter the levels of nitrates, indicating a direct effect of the compounds on amastigote stages. The results presented herein suggest that the active components from B. uncinella can be important to the design of new drugs against American tegumentar leishmaniases.
- Treatment with triterpenic fraction purified from Baccharis uncinella leaves inhibits Leishmania (Leishmania) amazonensis spreading and improves Th1 immune response in infected mice(2014) YAMAMOTO, Eduardo Seiji; CAMPOS, Bruno Luiz S.; LAURENTI, Marcia Dalastra; LAGO, Joao H. G.; GRECCO, Simone dos Santos; CORBETT, Carlos E. P.; PASSERO, Luiz Felipe D.The current medications used to treat leishmaniasis have many side effects for patients; in addition, some cases of the disease are refractory to treatment. Therefore, the search for new leishmanicidal compounds is indispensable. Recently, it was demonstrated that oleanolic- and ursolic-containing fraction from Baccharis uncinella leaves eliminated the promastigote and amastigote forms of Leishmania (Leishmania) amazonensis and L. (Viannia) braziliensis without causing toxic effects for J774 macrophages. Thus, the aim of the present work was to characterize the therapeutic effect of the triterpenic fraction in L. (L.) amazonensis-infected BALB/c mice. Oleanolic- and ursolic acid-containing fraction was extracted from B. uncinella leaves using organic solvents and chromatographic procedures. L. (L.) amazonensis-infected BALB/c mice were treated intraperitoneally with triterpenic fraction during five consecutive days with 1.0 and 5.0 mg/kg of triterpenic fraction, or with 10.0 mg/kg of amphotericin B drug. Groups of mice treated with the triterpenic fraction, presented with decreased lesion size and low parasitism of the skin-both of which were associated with high amounts of interleukin-12 and interferon gamma. The curative effect of this fraction was similar to amphotericin B-treated mice; however, the final dose, required to eliminate amastigotes, was lesser than amphotericin B. Moreover, triterpenic fraction did not cause microscopic alterations in liver, spleen, heart, lung, and kidney of experimental groups. This work suggests that this fraction possesses compounds that are characterized by leishmanicidal and immunomodulatory activities. From this perspective, the triterpenic fraction can be explored as a new therapeutic agent for use against American Tegumentar Leishmaniasis.
- Evaluation of anti-inflammatory activity of derivatives from aerial parts of Baccharis uncinella(2011) ZALEWSKI, Cynthia A.; PASSERO, Luiz Felipe D.; MELO, Alexis S. R. B.; CORBETT, Carlos Eduardo P.; LAURENTI, Marcia D.; TOYAMA, Marcos H.; TOYAMA, Daniela O.; ROMOFF, Paulete; FAVERO, Oriana A.; LAGO, Joao Henrique G.Context: Species of Baccharis exhibit antibiotic, antiseptic, and wound-healing properties, and have been used in the traditional medicine of South America for the treatment of inflammation, headaches, diabetes, and hepatobiliary disorders. Objective: To investigate the anti-inflammatory activity of organic phases from EtOH extract of the aerial parts of Baccharis uncinella DC (Asteraceae). Materials and methods: The crude EtOH extract from the aerial parts of B. uncinella was subjected to partition procedures and the corresponding CH(2)Cl(2) and EtOAc phases were subjected to several chromatographic separation procedures. Thus, these phases and their purified compounds were assayed for evaluation of anti-inflammatory activity. Results: The CH(2)Cl(2) phase from EtOH extract from B. uncinella contained two triterpenoids (oleanolic and ursolic acids) and one flavonoid (pectolinaringenin), whereas the respective EtOAc phase showed to be composed mainly by two phenylpropanoid derivatives (caffeic and ferulic acids). The CH(2)Cl(2) and EtOAc phases as well as their isolated compounds exhibited anti-inflammatory effects against inflammatory reactions induced by phospholipase A2 (from Crotalus durissus terrificus venom) and by carrageenan. Discussion and conclusion: The results suggested that the components obtained from partition phases of EtOH extract of B. uncinella could represent lead molecules for the development of anti-inflammatory agents. Additionally, the results confirmed the use of Baccharis genus in the traditional medicine of South America for the treatment of inflammation and other heath disorders. To date, the present work describes for the first time the anti-inflammatory effects of compounds isolated from B. uncinella.
- Antileishmanial activity evaluation of adunchalcone, a new prenylated dihydrochalcone from Piper aduncum L.(2014) PICOLO, Camilla R. Dal; BEZERRA, Mariana P.; GOMES, Kaio S.; PASSERO, Luiz Felipe D.; LAURENTI, Marcia D.; MARTINS, Euder Glendes A.; SARTORELLI, Patricia; LAGO, Joao Henrique G.Bioactivity-guided fractionation of EtOH extract from the leaves of Piper aduncum L. (Piperaceae) afforded a new dihydrochalcone, named adunchalcone. Its structure was elucidated on the basis of their spectroscopic data, primarily NMR and MS. Adunchalcone was evaluated against promastigote forms of Leishmania (L.) amazonensis, L. (V.) braziliensis, L. (V.) shawl, and L. (L.) chagasi and displayed 50% effective concentrations (EC50) of 11.03, 26.70, and 11.26 mu M, as well as selective indexes of 4.86, 2.01, 4.76 and 0.50, respectively. This compound was also tested against intracellular forms of L. (L.) amazonensis, displaying weak activity, in comparison to reference drug amphotericin B. However, despite reduced effect of adunchalcone against amastigotes of L. (L.) amazonensis, this work opens the perspective to use this particular molecule as a scaffold for the design of novel and selective drug candidates for neglected diseases, mainly leishmaniasis.