MARTA LOPES LIMA
Projetos de Pesquisa
Unidades Organizacionais
9 resultados
Resultados de Busca
Agora exibindo 1 - 9 de 9
- New alkenyl derivative from Piper malacophyllum and analogues: Antiparasitic activity against Trypanosoma cruzi and Leishmania infantum(2017) VARELA, Marina T.; LIMA, Marta L.; GALUPPO, Mariana K.; TEMPONE, Andre G.; OLIVEIRA, Alberto de; LAGO, Joao Henrique G.; FERNANDES, Joao Paulo S.Alkylphenols isolated from Piper malacophyllum (Piperaceae), gibbilimbols A and B, showed interesting activity against the parasites Trypanosoma cruzi and Leishmania infantum. In continuation to our previous work, a new natural product from the essential oil of the leaves of P.malacophyllum was isolated, the 5-[(3E)-oct-3-en-1-il]-1,3-benzodioxole, and also a new set of five compounds was prepared. The antiparasitic activity of the natural product was evaluated in vitro against these parasites, indicating potential against the promastigote/trypomastigote/amastigote forms (IC50 32-83m) of the parasites and low toxicity (CC50>200m) to mammalian cells. The results obtained to the synthetic compounds indicated that the new derivatives maintained the promising antiparasitic activity, but the cytotoxicity was considerably lowered. The amine derivative LINS03011 displayed the most potent IC50 values (13.3 and 16.7m) against amastigotes of T.cruzi and L.infantum, respectively, indicating comparable activity to the phenolic prototype LINS03003, with threefold decreased (CC50 73.5m) cytotoxicity, leading the selectivity index (SI) towards the parasites up to 24.5. In counterpart, LINS03011 has not shown membrane disruptor activity in SYTOX Green model. In summary, this new set showed the hydroxyl is not essential for the antiparasitic activity, and its substitution could decrease the toxicity to mammalian cells.
- Membrane targeting peptides toward antileishmanial activity: Design, structural determination and mechanism of interaction(2017) MARTINS, Danubia Batista; VIEIRA, Maira Ramos; FADEL, Valmir; SANTANA, Viviane Aparecida Camargo; GUERR, Mirian Elisa Rodrigues; LIMA, Marta Lopes; TEMPONE, Andre G.; CABRERA, Marcia Perez dos SantosBackground: Leishmaniasis threatens poor areas population worldwide, requiring new drugs less prone to resistance development. Antimicrobial peptides with antileishmanial activity are considered among fulfilling alternatives, but not much is known about the mode of action of membrane-targeting peptides, considering promastigote and infected macrophage membranes. In a previous work, structural features of very active known peptides were prospected using molecular dynamics simulations. Methods: Combining sequences of these peptides, analogs were designed. The structure of analog DecP-11 was validated by NMR. In vitro bioassays determined the peptide cytotoxicity toward mammalian cells, IC50 values on promastigotes and amastigotes, and membranolytic activity compared to Decoralin, one of the parent peptides. With biophysical methods, the mechanism of interaction with membrane mimetic systems was investigated. Results: The designed peptide exhibits potent cytolytic and membrane permeabilizing activities, and decreased antileishmanial activity compared to the parent peptide. Interactions with lipid bilayers mimicking those of promastigotes, infected macrophage and mammalian cells showed that these peptides strongly bind to vesicles with intense lytic activity at low concentrations. Additionally, circular dichroism and light scattering experiments showed changes in the secondary structure of peptides and in vesicle size, depending on vesicles compositions. Altogether they suggest that DecP-11 antileishmanial activity is impaired by the aggregation and that aminophospholipids are probably involved. Conclusions: DecP-11 potent cytolytic and membranolytic activities with lack of selectivity toward promastigote model membranes warrant further structural studies to improve selectivity.
- Neolignans from leaves of Nectandra leucantha (Lauraceae) display in vitro antitrypanosomal activity via plasma membrane and mitochondrial damages(2017) GRECCO, Simone S.; COSTA-SILVA, Thais A.; JERZ, Gerold; SOUSA, Fernanda S. de; LONDERO, Vinicius S.; GALUPPO, Mariana K.; LIMA, Marta L.; NEVES, Bruno J.; ANDRADE, Carolina H.; TEMPONE, Andre G.; LAGO, Joao Henrique G.Chagas disease is a neglected tropical disease, caused by the protozoan parasite Trypanosoma cruzi, which affects more than eight million people in Tropical and Subtropical countries especially in Latin America. Current treatment is limited to nifurtimox and benznidazole, both with reduced effectiveness and high toxicity. In this work, the n-hexane extract from leaves of Nectandra leucantha (Lauraceae) displayed in vitro antitrypanosomal activity against T. cruzi. Using several chromatographic steps, four related neolignans were isolated and chemically characterized as dehydrodieugenol B (1), 1-(8-propenyl)-3-[3'-methoxy-1'-(8-propenyl)-phenoxy]-4,5dimethoxybenzene (2), 1-[(7S)-hydroxy-8-propenyl]-3-[3'-methoxy-1'-(8'-propenyl)-phenoxy]-4hydroxy-5-methoxybenzene (3), and 1-[(7S)-hydroxy-8-propenyl]-3-[3'-methoxy-1'-(8'-propenyl)-phenoxy]-4,5-dimethoxybenzene (4). These compounds were tested against intracellular amastigotes and extracellular trypomastigotes of T. cruzi and for mammalian cytotoxicity. Neolignan 4 showed the higher selectivity index (SI) against trypomastigotes (>5) and amastigotes (>13) of T. cruzi. The investigation of the mechanism of action demonstrated that neolignan 4 caused substantial alteration of the plasma membrane permeability, together with mitochondrial dysfunctions in trypomastigote forms. In silico studies of pharmacokinetics and toxicity (ADMET) properties predicted that all compounds were non-mutagenic, non-carcinogenic, non-genotoxic, weak hERG blockers, with acceptable volume of distribution (1.66-3.32 L/kg), and low rodent oral toxicity (LD50 810-e2200 mg/kg). Considering some clinical events of cerebral Chagas disease, the compounds also demonstrated favorable properties, such as blood-brain barrier penetration. Unfavorable properties were also predicted as high promiscuity for P450 isoforms, high plasma protein binding affinity (>91%), and moderate-to-low oral bioavailability. Finally, none of the isolated neolignans was predicted as interference compounds (PAINS). Considering the promising chemical and biological properties of the isolated neolignans, these compounds could be used as starting points to develop new lead compounds for Chagas disease.
- Ergosterol isolated from the basidiomycete Pleurotus salmoneostramineus affects Trypanosoma cruzi plasma membrane and mitochondria(2017) ALEXANDRE, Tatiana Rodrigues; LIMA, Marta Lopes; GALUPPO, Mariana Kolos; MESQUITA, Juliana Tonini; NASCIMENTO, Matilia Ana do; SANTOS, Augusto Leonardo dos; SARTORELLI, Patricia; PIMENTA, Daniel Carvalho; TEMPONE, Andre GustavoBackground: Major drawbacks of the available treatment against Chagas disease (American trypanosomiasis) include its toxicity and therapeutic inefficiency in the chronic phase of the infection, which makes it a concern among neglected diseases. Therefore, the discovery of alternative drugs for treating chronic Chagas disease requires immediate action. In this work, we evaluated the mushroom Pleurotus salmoneostramineus in the search for potential antiparasitic compounds. Methods: Fruit bodies of the basidiomycete Pleurotus salmoneostramineus were triturated and submitted to organic solvent extraction. After liquid-liquid partition of the crude extract, three fractions were obtained and the bioguided fractionation study was conducted to isolate the active metabolites. The elucidation of the chemical structure was performed using GC-MS and NMR techniques. The biological assays for antiparasitic activity were carried out using trypomastigotes of Trypanosoma cruzi and murine macrophages for mammalian cytotoxicity. The mechanism of action of the isolated compound used different fluorescent probes to evaluate the plasma membrane permeability, the potential of the mitochondrial membrane and the intracellular levels of reactive oxygen species (ROS). Results: The most abundant fraction showing the antiparasitic activity was isolated and chemically elucidated, confirming the presence of ergosterol. It showed anti-Trypanosoma cruzi activity against trypomastigotes, with an IC50 value of 51.3 mu g/mL. The compound demonstrated no cytotoxicity against mammalian cells to the maximal tested concentration of 200 mu g/mL. The mechanism of action of ergosterol in Trypanosoma cruzi trypomastigotes resulted in permeabilization of the plasma membrane, as well as depolarization of mitochondrial membrane potential, leading to parasite death. Nevertheless, no increase in ROS levels could be observed, suggesting damages to plasma membrane rather than an induction of oxidative stress in the parasite. Conclusions: The selection of naturally antiparasitic secondary metabolites in basidiomycetes, such as ergosterol, may provide potential scaffolds for drug design studies against neglected diseases.
- Antiparasitic activity of new gibbilimbol analogues and SAR analysis through efficiency and statistical methods(2018) VARELA, Marina T.; ROMANELI, Maiara M.; LIMA, Marta L.; BORBOREMA, Samanta E. T.; TEMPONE, Andre G.; FERNANDES, Joao P. S.Chagas' disease and leishmaniasis are parasitic infections enrolled among the neglected tropical diseases, which urge for new treatments. In the search for new chemical entities as prototypes, gibbilimbols A/B have shown antiparasitic activity against Trypanosoma cruzi and Leishmania infantum, and then a set of analogues (LINS03 series) of this natural product were synthesized and evaluated in vitro against the parasites. In the present paper we reported five new compounds with activity against these protozoan parasites, and quite low cytotoxicity. Moreover, the interference of plasma membrane permeability of these analogues were also evaluated. We found that [(4-methoxyphenyl) methyl] octylamine (4) was noteworthy due to its high activity against the amastigote form of both parasites (IC50 1.3-5.8 mu M) and good selectivity index. In order to unveil the SAR for this chemotype, we also presented a group efficiency analysis and PCA and HCA study, which indicated that the methoxyl provides good activity with lower cytotoxicity to mammalian cells. The results from SAR analyses suggest different mechanisms of action between the neutral and basic compounds. In summary, the analogues represent important activity against these parasites and must be prototypes for further exploitation.
- Metabolomics as a tool to evaluate the toxicity of formulations containing amphotericin B, an antileishmanial drug(2016) SANTOS, Delia C. M.; LIMA, Marta L.; TOLEDO, Juliano S.; FERNANDES, Paula A.; AGUIAR, Marta M. G.; LOPEZ-GONZALVEZ, Angeles; FERREIRA, Lucas A. M.; FERNANDES, Ana Paula; BARBAS, CoralAmphotericin B (AmB) is a drug of choice against life-threatening systemic fungal infections and an alternative therapy for the treatment of all forms of leishmaniasis. It is known that AmB and its conventional formulation cause renal damage; however, the lipid formulations can reduce these effects. The aim of the present study was to identify metabolic changes in mice treated with two different AmB formulations, a nanoemulsion (NE) (lipid system carrier) loaded with AmB and the conventional formulation (C-AmB). For this purpose, metabolic fingerprinting represents a valuable strategy to monitor, in a non-targeted manner, the changes that are at the base of the toxicity mechanism of AmB. Plasma samples of BALB-c mice were collected after treatment with 3 alternate doses of AmB at 1 mg kg(-1) administered intravenously and analysed with CE, LC and GC coupled to MS. Blood urea nitrogen (BUN) and plasma creatinine levels were also analysed. Kidney tissue specimens were collected and evaluated. It was not observed that there were any alterations in BUN and creatinine levels as well as in histopathological analysis. Approximately 30 metabolites were identified as potentially related to early C-AmB-induced nephrotoxicity. Disturbances in the arachidonic acid, glycerophospholipid, acylcarnitine and polyunsaturated fatty acid (PUFA) pathways were observed in C-AmB-treated mice. In the AmB-loaded NE group, it was observed that there were fewer metabolic changes, including changes in the plasma levels of cortisol and pyranose. The candidate biomarkers revealed in this study could be useful in the detection of the onset and severity of kidney injury induced by AmB formulations.
- Investigation of the Anti-Leishmania (Leishmania) infantum Activity of Some Natural Sesquiterpene Lactones(2017) WULSTEN, Imke E.; COSTA-SILVA, Thais A.; MESQUITA, Juliana T.; LIMA, Marta L.; GALUPPO, Mariana K.; TANIWAKI, Noemi N.; BORBOREMA, Samanta E. T.; COSTA, Fernando B. Da; SCHMIDT, Thomas J.; TEMPONE, Andre G.Leishmaniases are neglected infectious diseases caused by parasites of the 'protozoan' genus Leishmania. Depending on the parasite species, different clinical forms are known as cutaneous, muco-cutaneous, and the visceral leishmaniasis (VL). VL is particularly fatal and the therapy presents limitations. In the search for new anti-leishmanial hit compounds, seven natural sesquiterpene lactones were evaluated against promastigotes and intracellular amastigotes of Leishmania (Leishmania) infantum, a pathogen causing VL. The pseudoguaianolides mexicanin I and helenalin acetate demonstrated the highest selectivity and potency against intracellular amastigotes. In addition, promastigotes treated with helenalin acetate were subject to an ultrastructural and biochemical investigation. The lethal action of the compound was investigated by fluorescence-activated cell sorting and related techniques to detect alterations in reactive oxygen species (ROS) content, plasma membrane permeability, and mitochondrial membrane potential. Helenalin acetate significantly reduced the mitochondrial membrane potential and the mitochondrial structural damage was also confirmed by transmission electron microscopy, displaying an intense organelle swelling. No alteration of plasma membrane permeability or ROS content could be detected. Additionally, helenalin acetate significantly increased the production of nitric oxide in peritoneal macrophages, probably potentiating the activity against the intracellular amastigotes. Helenalin acetate could hence be a useful anti-leishmanial scaffold for further optimization studies.
- Cyclobenzaprine Raises ROS Levels in Leishmania infantum and Reduces Parasite Burden in Infected Mice(2017) CUNHA-JUNIOR, Edezio Ferreira; ANDRADE-NETO, Valter Viana; LIMA, Marta Lopes; COSTA-SILVA, Thais Alves da; GALISTEO JUNIOR, Andres J.; ABENGOZAR, Maria A.; BARBAS, Coral; RIVAS, Luis; ALMEIDA-AMARAL, Elmo Eduardo; TEMPONE, Andre Gustavo; TORRES-SANTOS, Eduardo CaioBackground The leishmanicidal action of tricyclic antidepressants has been studied and evidences have pointed that their action is linked to inhibition of trypanothione reductase, a key enzyme in the redox metabolism of pathogenic trypanosomes. Cyclobenzaprine (CBP) is a tricyclic structurally related to the antidepressant amitriptyline, differing only by the presence of a double bond in the central ring. This paper describes the effect of CBP in experimental visceral leishmaniasis, its inhibitory effect in trypanothione reductase and the potential immunomodulatory activity. Methodology/Principal Findings In vitro antileishmanial activity was determined in promastigotes and in L. infantum-infected macrophages. For in vivo studies, L. infantum-infected BALB/c mice were treated with CBP by oral gavage for five days and the parasite load was estimated. Trypanothione reductase activity was assessed in the soluble fraction of promastigotes of L. infantum. For evaluation of cytokines, L. infantum-infected macrophages were co-cultured with BALB/c splenocytes and treated with CBP for 48 h. The supernatant was analyzed for IL-6, IL-10, MCP-1, IFN-gamma and TNF-alpha. CBP demonstrated an IC50 of 14.5 +/- 1.1 mu M and an IC90 of 74.5 +/- 1.2 mu M in promastigotes and an IC50 of 12.6 +/- 1.05 mu M and an IC90 of 28.7 +/- 1.3 mu M in intracellular amastigotes. CBP also reduced the parasite load in L. infantum-infected mice by 40.4 +/- 10.3% and 66.7 +/- 10.5% in spleen at 24.64 and 49.28 mg/kg, respectively and by 85.6 +/- 5.0 and 89.3 +/- 4.8% in liver at 24.64 and 49.28mg/kg, after a short-term treatment. CBP inhibited the trypanothione reductase activity with a Ki of 86 +/- 7.7 mu M and increased the ROS production in promastigotes. CBP inhibited in 53% the production of IL-6 in infected macrophages coculture. Conclusion/Significance To the best of our knowledge, this study is the first report of the in vivo antileishmanial activity of the FDA-approved drug CBP. Modulation of immune response and induction of oxidative stress in parasite seem to contribute to this efficacy.
- Antileishmanial Activity and Immunomodulatory Effects of Tricin Isolated from Leaves of Casearia arborea (Salicaceae)(2017) SANTOS, Augusto L.; YAMAMOTO, Eduardo S.; PASSERO, Luiz Felipe D.; LAURENTI, Marcia D.; MARTINS, Ligia F.; LIMA, Marta L.; UEMI, Miriam; SOARES, Marisi G.; LAGO, Joao Henrique G.; TEMPONE, Andre G.; SARTORELLI, PatriciaBioactivity-guided fractionation of antileishmanial active extract from leaves of Casearia arborea led to isolation of three metabolites: tricin (1), 1,6 '-di-O-beta-D-vanilloyl glucopyranoside (2) and vanillic acid (3). Compound 1 demonstrated the highest activity against the intracellular amastigotes of Leishmania infantum, with an IC50 value of 56 mu m. Tricin (1) demonstrated selectivity in mammalian cells (SI > 7) and elicited immunomodulatory effect on host cells. The present work suggests that tricin modulated the respiratory burst of macrophages to a leishmanicidal state, contributing to the parasite elimination. Therefore, the natural compound tricin could be further explored in drug design studies for leishmaniasis treatment.