| leishmania braziliensis replication protein a subunit 1: molecular modelling, protein expression and analysis of its affinity for both dna and rna. | replication factor a (rpa) is a single-strand dna binding protein involved in dna replication, recombination and repair processes. it is composed by the subunits rpa-1, rpa-2 and rpa-3; the major dna-binding activity resides in the subunit 1 of the heterotrimeric rpa complex. in yeast and higher eukaryotes, besides the three basic structural dna-binding domains, the rpa-1 subunit contains an n-terminal region involved in protein-protein interactions with a fourth dna-binding domain. remarkably, ... | 2014 | 25498946 |
| il-27 enhances leishmania amazonensis infection via ds-rna dependent kinase (pkr) and il-10 signaling. | the protozoan parasite leishmania infects and replicates in macrophages, causing a spectrum of diseases in the human host, varying from cutaneous to visceral clinical forms. it is known that cytokines modulate the immunological response against leishmania and are relevant for infection resolution. here, we report that interleukin (il)-27 increases leishmania amazonensis replication in human and murine macrophages and that the blockage of the il-10 receptor on the surface of infected cells abolis ... | 2015 | 25466588 |
| synthesis and biological evaluation of novel 2,3-disubstituted quinoxaline derivatives as antileishmanial and antitrypanosomal agents. | quinoxalines belong to the n-containing heterocyclic compounds that stand out as having promising biological activity due to their privileged scaffold. in this work, we report the synthesis, antileishmanial, and antitrypanosomal properties of 46 new 2,3-disubstituted quinoxaline and 40 previously reported derivatives. among all of the compounds screened for in vitro activity against epimastigotes and trypomastigotes of trypanosoma cruzi and promastigotes of leishmania amazonensis as well as mamm ... | 2015 | 25461316 |
| syzygium cumini (l.) skeels essential oil and its major constituent α-pinene exhibit anti-leishmania activity through immunomodulation in vitro. | syzygium cumini (l.) skeels (myrtaceae), commonly known as "jambolão" in brazil is widely used in folk medicine against leishmaniasis, inflammation, chronic diarrhea, and ulcers. it is one of the most commonly used plants for the treatment of diabetes worldwide. in previous studies, syzygium cumini was shown to possess antihyperlipidemic and anti-allergic properties, and to exhibit good performance as an antimicrobial agent against bacteria, fungi, and protozoa parasites of the genus leishmania ... | 2015 | 25460590 |
| rpa-1 from leishmania amazonensis (larpa-1) structurally differs from other eukaryote rpa-1 and interacts with telomeric dna via its n-terminal ob-fold domain. | replication protein a-1 (rpa-1) is a single-stranded dna-binding protein involved in dna metabolism. we previously demonstrated the interaction between larpa-1 and telomeric dna. here, we expressed and purified truncated mutants of larpa-1 and used circular dichroism measurements and molecular dynamics simulations to demonstrate that the tertiary structure of larpa-1 differs from human and yeast rpa-1. larpa-1 interacts with telomeric ssdna via its n-terminal ob-fold domain, whereas rpa from hig ... | 2014 | 25451229 |
| in vitro evaluation of (-)α-bisabolol as a promising agent against leishmania amazonensis. | current treatments for leishmaniasis present some difficulties due to their toxicity, the use of the intravenous route for administration and therapy duration, which may lead to treatment discontinuation. the aim of this study is to investigate new treatment alternatives to improve patients well being. therefore, we evaluated the inhibitory effect of (-)α-bisabolol, a sesquiterpene alcohol found in various essential oils of different plant species, against the promastigotes and intracellular ama ... | 2015 | 25448354 |
| an optimized nanoparticle delivery system based on chitosan and chondroitin sulfate molecules reduces the toxicity of amphotericin b and is effective in treating tegumentary leishmaniasis. | amphotericin b (ampb) is active against leishmaniasis, but its use is hampered due to its high toxicity observed in patients. in this study, a nanoparticles-delivery system for ampb (nqc-ampb), containing chitosan and chondroitin sulfate molecules, was evaluated in balb/c mice against leishmania amazonensis. an in vivo biodistribution study, including biochemical and toxicological evaluations, was performed to evaluate the toxicity of ampb. nanoparticles were radiolabeled with technetium-99m and ... | 2014 | 25429219 |
| [cutaneous leishmaniosis: unusual clinical manifestation]. | clinical manifestations of leishmaniasis are diverse and related to the infecting species, its relationship with the environment and the host immune response. a case of late andean cutaneous leishmaniasis with extensive manifestation is presented. the case was confirmed through microbiological and immunological studies; identification was performed by cytochrome b gene sequencing and the species was determined as leishmania (leishmania) amazonensis. the patient was treated with sodium stibogluco ... | 2016 | 25418662 |
| protective effects of the antileishmanial extract of tephrosia cinerea (l.) pers. (fabaceae) against cyclophosphamide-induced damage. | tephrosia cinerea l. (pers.) is a tropical species that exhibits antileishmanial activity in leishmania amazonensis promastigote cultures and is commonly used to treat infections, inflammations, ulcers, nervous conditions, and diarrhea. however, no studies have investigated its effects on genetic material. therefore, we evaluated the genotoxic potential, antigenotoxic potential, and cytotoxic effects of hydroalcoholic extracts of t. cinerea leaves. in an in vitro genotoxicity study, human periph ... | 2014 | 25366795 |
| pterocarpanquinone lqb-118 induces apoptosis in leishmania (viannia) braziliensis and controls lesions in infected hamsters. | previous results demonstrate that the hybrid synthetic pterocarpanquinone lqb-118 presents antileishmanial activity against leishmania amazonensis in a mouse model. the aim of the present study was to use a hamster model to investigate whether lqb-118 presents antileishmanial activity against leishmania (viannia) braziliensis, which is the major leishmania species related to american tegumentary leishmaniasis. the in vitro antileishmanial activity of lqb-118 on l. braziliensis was tested on the ... | 2014 | 25340550 |
| the comparative genomics and phylogenomics of leishmania amazonensis parasite. | leishmaniasis is an infectious disease caused by leishmania species. leishmania amazonensis is a new world leishmania species belonging to the mexicana complex, which is able to cause all types of leishmaniasis infections. the l. amazonensis reference strain mhom/br/1973/m2269 was sequenced identifying 8,802 codifying sequences (cds), most of them of hypothetical function. comparative analysis using six leishmania species showed a core set of 7,016 orthologs. l. amazonensis and leishmania mexica ... | 2014 | 25336895 |
| evidences for leishmanicidal activity of the naphthoquinone derivative epoxy-α-lapachone. | in this work, we analyze the leishmanicidal effects of epoxy-α-lapachone on leishmania (viannia) braziliensis and leishmania (leishmania) amazonensis. promasigotes and amastigotes (inhabiting human macrophages) from both species were assayed to verify the compound's activity over the distinct morphological stages. the incubation with epoxy-α-lapachone led to a significant decrease in the numbers of promastigotes from both species in the cultures, in a dose-and time-dependent fashion. the surviva ... | 2014 | 25307687 |
| insulin-like growth factor-i induces arginase activity in leishmania amazonensis amastigote-infected macrophages through a cytokine-independent mechanism. | leishmania (leishmania) amazonensis exhibits peculiarities in its interactions with hosts. because amastigotes are the primary form associated with the progression of infection, we studied the effect of insulin-like growth factor (igf)-i on interactions between l. (l.) amazonensis amastigotes and macrophages. upon stimulation of infected macrophages with igf-i, we observed decreased nitric oxide production but increased arginase expression and activity, which lead to increased parasitism. howeve ... | 2014 | 25294956 |
| photodynamic effects of zinc phthalocyanines on intracellular amastigotes of leishmania amazonensis and leishmania braziliensis. | this study investigated the photoactivity of four zinc phthalocyanines (pczns) on a murine macrophage cell line infected with leishmania amazonensis or leishmania braziliensis. infected and uninfected cells were incubated with pczns at different concentrations (1-10 μm) for 3 h and then exposed to an led device in continuous wave mode at 660 nm with a fluency of 50 j/cm(2) (25 mv). enzymatic activity was determined by mtt assay 24 h after light treatment. the results demonstrated that all pczns ... | 2015 | 25288263 |
| nanobiotechnologic approach to a promising vaccine prototype for immunisation against leishmaniasis: a fast and effective method to incorporate gpi-anchored proteins of leishmania amazonensis into liposomes. | liposomes are known to be a potent adjuvant for a wide range of antigens, as well as appropriate antigen carriers for antibody generation response in vivo. in addition, liposomes are effective vehicles for peptides and proteins, thus enhancing their immunogenicity. considering these properties of liposomes and the antigenicity of the leishmania membrane proteins, we evaluated if liposomes carrying glycosylphosphatidylinositol (gpi)-anchored proteins of leishmania amazonensis promastigotes could ... | 2015 | 25265060 |
| cell death and ultrastructural alterations in leishmania amazonensis caused by new compound 4-nitrobenzaldehyde thiosemicarbazone derived from s-limonene. | the treatment of leishmaniasis with pentavalent antimonials is problematic because of their toxicity. investigations of potentially active molecules are important to discover less toxic drugs that are viable economic alternatives for the treatment of leishmaniasis. thiosemicarbazones are a group of molecules that are known for their wide versatility and biological activity. in the present study, we examined the antileishmania activity, mechanism of action, and biochemical alterations produced by ... | 2014 | 25253283 |
| leishmanicidal compounds and potent pparγ activators from renealmia thyrsoidea (ruiz & pav.) poepp. & endl. | leaves and rhizomes of renealmia thyrsoidea (ruiz & pav.) poepp. & endl. traditionally used in the yanesha pharmacopoeia to treat skin infections such as leishmaniasis ulcers, or to reduce fever were chemically investigated to identify leishmanicidal compounds, as well as pparγ activators. | 2014 | 25251262 |
| synthesis, leishmanicidal activity and theoretical evaluations of a series of substituted bis-2-hydroxy-1,4-naphthoquinones. | a series of eight substituted bis-2-hydroxy-1,4-naphthoquinone derivatives was synthesized through lawsone condensation with various aromatic and aliphatic aldehydes under mild acidic conditions. the title compounds were evaluated for antileishmanial activity in vitro against leishmania amazonensis and leishmania braziliensis promastigotes; six compounds showed good activity without significant toxic effects. the compound with the highest activity was used for an in vivo assay with leishmania am ... | 2014 | 25247686 |
| intranasal vaccination with extracellular serine proteases of leishmania amazonensis confers protective immunity to balb/c mice against infection. | previously, we demonstrated that unlike subcutaneous or intramuscular vaccination, intranasal vaccination of balb/c mice with whole leishmania amazonensis antigens leads to protection against cutaneous leishmaniasis. here, the role of parasite serine proteases in the protective immunity was investigated. | 2014 | 25239157 |
| extracellular vesicles from leishmania-infected macrophages confer an anti-infection cytokine-production profile to naïve macrophages. | extracellular vesicles (evs) are structures with phospholipid bilayer membranes and 100-1000 nm diameters. these vesicles are released from cells upon activation of surface receptors and/or apoptosis. the production of evs by dendritic cells, mast cells, macrophages, and b and t lymphocytes has been extensively reported in the literature. evs may express mhc class ii and other membrane surface molecules and carry antigens. the aim of this study was to investigate the role of evs from leishmania- ... | 2014 | 25232947 |
| effectiveness of miltefosine-pentoxifylline compared to miltefosine in the treatment of cutaneous leishmaniasis in c57bl/6 mice. | the treatment of leishmaniasis ischallenging, given the difficulties in drug administration and resistance. therefore, we chose to test the efficacy of miltefosine combined with pentoxifylline. | 2014 | 25229296 |
| n-butyl-[1-(4-methoxy)phenyl-9h-β-carboline]-3-carboxamide prevents cytokinesis in leishmania amazonensis. | leishmaniasis, a complex of diseases caused by protozoa of the genus leishmania, is endemic in 98 countries, affecting approximately 12 million people worldwide. current treatments for leishmaniasis have many disadvantages, such as toxicity, high costs, and prolonged treatment, making the development of new treatment alternatives highly relevant. several studies have verified the antileishmanial activity of β-carboline compounds. in the present study, we investigated the in vitro antileishmanial ... | 2014 | 25224005 |
| the in vitro biological activity of the brazilian brown seaweed dictyota mertensii against leishmania amazonensis. | seaweeds present a wide variety of interesting bioactive molecules. in the present work we evaluated the biological activity of the dichloromethane/methanol (2:1) extract (dme) from the brown seaweed dictyota mertensii against leishmania amazonensis and its cytotoxic potential on mammalian cells. the extract showed significant inhibitory effect on the growth of promastigote forms (ic50=71.60 μg/ml) and low toxicity against mammalian cells (cc50=233.10 μg/ml). the dme was also efficient in inhibi ... | 2014 | 25207712 |
| furofuran lignans display schistosomicidal and trypanocidal activities. | parasitic diseases continue to be a major worldwide health problem, and there is an urgent need for development of therapeutic drugs. this paper describes synthesis of dehydrodiferulic acid dilactone 1 and dehydrodisinapic acid dilactone 2 furofuran lignans by oxidative coupling of ferulic and sinapic acids, respectively. their schistosomicidal, trypanocidal, and leishmanicidal activities were evaluated in vitro against schistosoma mansoni adult worms, trypomastigote and amastigotes forms of try ... | 2014 | 25200100 |
| an in vitro model of antibody-enhanced killing of the intracellular parasite leishmania amazonensis. | footpad infection of c3heb/fej mice with leishmania amazonensis leads to chronic lesions accompanied by large parasite loads. co-infecting these animals with l. major leads to induction of an effective th1 immune response that can resolve these lesions. this cross-protection can be recapitulated in vitro by using immune cells from l. major-infected animals to effectively activate l. amazonensis-infected macrophages to kill the parasite. we have shown previously that the b cell population and the ... | 2014 | 25191842 |
| leishmania amazonensis: increase in ecto-atpase activity and parasite burden of vinblastine-resistant protozoa. | leishmania amazonensis is a protozoan parasite that induces mucocutaneous and diffuse cutaneous lesions upon infection. an important component in treatment failure is the emergence of drug-resistant parasites. it is necessary to clarify the mechanism of resistance that occurs in these parasites to develop effective drugs for leishmaniasis treatment. promastigote forms of l. amazonensis were selected by gradually increasing concentrations of vinblastine and were maintained under continuous drug p ... | 2014 | 25176449 |
| leishmania amazonensis infection impairs dendritic cell migration from the inflammatory site to the draining lymph node. | in vitro studies show that leishmania infection decreases the adhesion of inflammatory phagocytes to connective tissue by a mechanism dependent on the modulation of integrin function. however, we know little about the influence of this reduction in leukocyte adhesion on parasite dissemination from the infection site. | 2014 | 25142021 |
| antileishmanial activity of medicinal plants used in endemic areas in northeastern brazil. | this study investigates the leishmanicidal activity of five species of plants used in folk medicine in endemic areas of the state of alagoas, brazil. data were collected in the cities of colonia leopoldina, novo lino, and união dos palmares, alagoas state, from patients with cutaneous leishmaniasis (leishmania amazonensis) who use medicinal plants to treat this disease. plants extracts were tested at a concentration of 1-100 μg/ml in all experiments, except in an assay to evaluate activity again ... | 2014 | 25126099 |
| arginase i, polyamine, and prostaglandin e2 pathways suppress the inflammatory response and contribute to diffuse cutaneous leishmaniasis. | diffuse cutaneous leishmaniasis (dcl) is a rare clinical manifestation of tegumentary leishmaniasis. the molecular mechanisms underlying dcl pathogenesis remain unclear, and there is no efficient treatment available. this study investigated the systemic and in situ expression of the inflammatory response that might contribute to suppression in dcl. the plasma levels of arginase i, ornithine decarboxylase (odc), transforming growth factor β (tgf-β), and prostaglandin e2 (pge2) were higher in pati ... | 2015 | 25124926 |
| resveratrol is active against leishmania amazonensis: in vitro effect of its association with amphotericin b. | resveratrol is a polyphenol found in black grapes and red wine and has many biological activities. in this study, we evaluated the effect of resveratrol alone and in association with amphotericin b (amb) against leishmania amazonensis. our results demonstrate that resveratrol possesses both antipromastigote and antiamastigote effects, with 50% inhibitory concentrations (ic50s) of 27 and 42 μm, respectively. the association of resveratrol with amb showed synergy for l. amazonensis amastigotes, as ... | 2014 | 25114129 |
| short-term protection conferred by leishvacin® against experimental leishmania amazonensis infection in c57bl/6 mice. | to date, there is no vaccine available against human leishmaniasis. although some vaccination protocols can induce immunity in murine models, they fail to induce protection in humans. the reasons for that remain unclear. the aim of the present study was to characterize the changes in the pattern of the immune response during subcutaneous vaccination with leishvacin® in mice. we also investigated whether ifn-γ and nitric oxide synthase are indispensable for the protection elicited by the vaccine. ... | 2014 | 25102355 |
| terpenes increase the lipid dynamics in the leishmania plasma membrane at concentrations similar to their ic50 values. | although many terpenes have shown antitumor, antibacterial, antifungal, and antiparasitic activity, the mechanism of action is not well established. electron paramagnetic resonance (epr) spectroscopy of the spin-labeled 5-doxyl stearic acid revealed remarkable fluidity increases in the plasma membrane of terpene-treated leishmania amazonensis promastigotes. for an antiproliferative activity assay using 5×10(6) parasites/ml, the sesquiterpene nerolidol and the monoterpenes (+)-limonene, α-terpine ... | 2014 | 25101672 |
| the new pyrazolyltetrazole derivative msn20 is effective via oral delivery against cutaneous leishmaniasis. | an orally delivered, safe and effective treatment for leishmaniasis is an unmet medical need. azoles and the pyrazolylpyrimidine allopurinol present leishmanicidal activity, but their clinical efficacies are variable. here, we describe the activity of the new pyrazolyltetrazole hybrid, 5-[5-amino-1-(4'-methoxyphenyl)1h-pyrazole-4-yl]1h-tetrazole (msn20). msn20 showed a 50% inhibitory concentration (ic50) of 22.3 μm against amastigotes of leishmania amazonensis and reduced significantly the paras ... | 2014 | 25092697 |
| liposomal formulation of turmerone-rich hexane fractions from curcuma longa enhances their antileishmanial activity. | promastigote forms of leishmania amazonensis were treated with different concentrations of two fractions of curcuma longa cortex rich in turmerones and their respective liposomal formulations in order to evaluate growth inhibition and the minimal inhibitory concentration (mic). in addition, cellular alterations of treated promastigotes were investigated under transmission and scanning electron microscopies. liporhic and liporhiwc presented lower mic, 5.5 and 12.5 μg/ml, when compared to nonencap ... | 2014 | 25045693 |
| leishmania amazonensis amastigotes highly express a tryparedoxin peroxidase isoform that increases parasite resistance to macrophage antimicrobial defenses and fosters parasite virulence. | professional phagocytes generate a myriad of antimicrobial molecules to kill invading microorganisms, of which nitrogen oxides are integral in controlling the obligate intracellular pathogen leishmania. although reactive nitrogen species produced by the inducible nitric oxide synthase (inos) can promote the clearance of intracellular parasites, some leishmania species/stages are relatively resistant to inos-mediated antimicrobial activity. the underlying mechanism for this resistance remains lar ... | 2014 | 25033301 |
| in vitro and in vivo miltefosine susceptibility of a leishmania amazonensis isolate from a patient with diffuse cutaneous leishmaniasis. | miltefosine was the first oral compound approved for visceral leishmaniasis chemotherapy, and its efficacy against leishmania donovani has been well documented. leishmania amazonensis is the second most prevalent species causing cutaneous leishmaniasis and the main etiological agent of diffuse cutaneous leishmaniasis in brazil. driven by the necessity of finding alternative therapeutic strategies for a chronic diffuse cutaneous leishmaniasis patient, we evaluated the susceptibility to miltefosin ... | 2014 | 25033218 |
| in vitro and in vivo activity of benzo[c]phenanthridines against leishmania amazonensis. | seven benzo[c]phenanthridines, synthetic or isolated from zanthoxylum rhoifolium root bark, were evaluated against leishmania amazonensis axenic amastigotes. five of them were considered leishmanicidal, with ic50 values ranging from 0.03 to 0.54 µm, and were evaluated on intramacrophagic amastigotes of l. amazonensis. chelerythrine displayed the best activity (ic50=0.5 µm), which was in the same range as the reference compound amphotericin b (ic50=0.4 µm). in vivo studies with chelerythrine, avi ... | 2014 | 25029171 |
| in vivo antileishmanial efficacy of miltefosine against leishmania (leishmania) amazonensis. | leishmaniasis, a disease caused by parasites of the leishmania genus, constitutes a significant health and social problem in many countries and is increasing worldwide. the conventional treatment, meglumine antimoniate (ma), presents numerous disadvantages, including invasiveness, toxicity, and frequent therapeutic failure, justifying the attempts at finding alternatives to the first-line therapy. we have studied the comparative long-term efficacy of ma against miltefosine (mf) in leishmania inf ... | 2014 | 25014108 |
| increased tau phosphorylation and receptor for advanced glycation endproducts (rage) in the brain of mice infected with leishmania amazonensis. | leishmaniasis is a parasitosis caused by several species of the genus leishmania, an obligate intramacrophagic parasite. although neurologic symptoms have been observed in human cases of leishmaniasis, the manifestation of neurodegenerative processes is poorly studied. the aim of the present work was to investigate if peripheral infection of balb/c mice with leishmania amazonensis affects tau phosphorylation and rage protein content in the brain, which represent biochemical markers of neurodegen ... | 2015 | 25014011 |
| functional properties and stability of spray-dried pigments from bordo grape (vitis labrusca) winemaking pomace. | the stability of anthocyanin and phenolic compounds, the antioxidant capacity, the antimicrobial activity and the capacity to inhibit arginase from leishmania were evaluated in spray-dried powders from bordo grape winemaking pomace extract. the pigments were produced using maltodextrin as the carrier agent at concentrations varying from 10% to 30% and air entrance temperatures varying from 130 to 170°c. a sample of freeze-dried extract without the carrier was also evaluated. the anthocyanins in ... | 2014 | 24996348 |
| nlr proteins and parasitic disease. | parasitic diseases are a serious global health concern. many of the most common and most severe parasitic diseases, including chagas' disease, leishmaniasis, and schistosomiasis, are also classified as neglected tropical diseases and are comparatively less studied than infectious diseases prevalent in high income nations. the nlrs (nucleotide-binding domain leucine-rich-repeat-containing proteins) are cytosolic proteins known to be involved in pathogen detection and host response. the role of nl ... | 2014 | 24989828 |
| leishmania donovani nucleoside hydrolase terminal domains in cross-protective immunotherapy against leishmania amazonensis murine infection. | nucleoside hydrolases of the leishmania genus are vital enzymes for the replication of the dna and conserved phylogenetic markers of the parasites. leishmania donovani nucleoside hydrolase (nh36) induced a main cd4(+) t cell driven protective response against l. chagasi infection in mice which is directed against its c-terminal domain. in this study, we used the three recombinant domains of nh36: n-terminal domain (f1, amino acids 1-103), central domain (f2 aminoacids 104-198), and c-terminal do ... | 2014 | 24966857 |
| synthesis and antiparasitic activity of new bis-arylimidamides: db766 analogs modified in the terminal groups. | fifteen novel bis-arylimidamide derivatives with various 6-membered (7a-c) and 5-membered (7d-o) heterocyclic rings replacing the terminal pyridyl rings of the lead compound db766{(2,5-bis[2-i-propoxy-4-(2-pyridylimino)aminophenylfuran]}, were prepared and evaluated versus trypanosoma cruzi, leishmania amazonensis, trypanosoma brucei rhodesiense and plasmodium falciparum. compound 7a with pyrimidine replacing the pyridine rings showed good activity versus t. cruzi, t. brucei rhodesiense and p. f ... | 2014 | 24956553 |
| cell death in amastigote forms of leishmania amazonensis induced by parthenolide. | leishmania amazonensis infection results in diverse clinical manifestations: cutaneous, mucocutaneous or visceral leishmaniasis. the arsenal of drugs available for treating leishmania infections is limited. therefore, new, effective, and less toxic leishmaniasis treatments are still needed. we verified cell death in amastigote forms of leishmania amazonensis induced by the sesquiterpene lactone parthenolide. | 2014 | 24913205 |
| leishmanicidal activities of novel synthetic furoxan and benzofuroxan derivatives. | a novel series of furoxan (1,2,5-oxadiazole 2-oxide) (compounds 3, 4a and -b, 13a and -b, and 14a to -f) and benzofuroxan (benzo[c][1,2,5]oxadiazole 1-oxide) (compounds 7 and 8a to -c) derivatives were synthesized, characterized, and evaluated for in vitro activity against promastigote and intracellular amastigote forms of leishmania amazonensis. the furoxan derivatives exhibited the ability to generate nitric oxide at different levels (7.8% to 27.4%). the benzofuroxan derivative 8a was able to ... | 2014 | 24913171 |
| in vitro and in vivo activity of major constituents from pluchea carolinensis against leishmania amazonensis. | the search for new therapeutic agents from natural sources has been a constant for the treatment of diseases such as leishmaniasis. herein, in vitro and in vivo pharmacological activities of pure major phenolic constituents (caffeic acid, chlorogenic acid, ferulic acid, quercetin, and rosmarinic acid) from pluchea carolinensis against leishmania amazonensis are presented. pure compounds showed inhibitory activity against promastigotes (ic50 = 0.2-0.9 μg/ml) and intracellular amastigotes (ic50 = ... | 2014 | 24906989 |
| impact of tumor necrosis factor receptor p55 deficiency in susceptibility of c57bl/6 mice to infection with leishmania (leishmania) amazonensis. | tumor necrosis factor (tnf) is involved in host resistance to several intracellular pathogens. although the critical role of tnf receptor (tnfr)p55 in leishmania (leishmania) major infection has been demonstrated, the impact of tnfrp55 deficiency on l. (l.) amazonensis infection has not been explored. l. (l.) amazonensis-infected tnfrp55(-/-) mice failed to resolve lesions, whereas c57bl/6 wild-type mice completely healed. the susceptibility of the tnfrp55(-/-) mice was characterized by higher l ... | 2016 | 24856420 |
| antileishmanial activity and cytotoxicity of brazilian plants. | leishmaniasis is a major public health problem, and the alarming spread of parasite resistance has increased the importance of discovering new therapeutic products. the present study aimed to investigate the in vitro leishmanicidal activity from 16 different brazilian medicinal plants. stationary-phase promastigotes of leishmania amazonensis and murine macrophages were exposed to 44 plant extracts or fractions for 48 h at 37°c, in order to evaluate their antileishmanial activity and cytotoxicity ... | 2014 | 24846006 |
| cross-protective immunity to leishmania amazonensis is mediated by cd4+ and cd8+ epitopes of leishmania donovani nucleoside hydrolase terminal domains. | the nucleoside hydrolase (nh) of leishmania donovani (nh36) is a phylogenetic marker of high homology among leishmania parasites. in mice and dog vaccination, nh36 induces a cd4+ t cell-driven protective response against leishmania chagasi infection directed against its c-terminal domain (f3). the c-terminal and n-terminal domain vaccines also decreased the footpad lesion caused by leishmania amazonensis. we studied the basis of the crossed immune response using recombinant generated peptides co ... | 2014 | 24822054 |
| arrabidaea chica hexanic extract induces mitochondrion damage and peptidase inhibition on leishmania spp. | currently available leishmaniasis treatments are limited due to severe side effects. arrabidaea chica is a medicinal plant used in brazil against several diseases. in this study, we investigated the effects of 5 fractions obtained from the crude hexanic extract of a. chica against leishmania amazonensis and l. infantum, as well as on the interaction of these parasites with host cells. promastigotes were treated with several concentrations of the fractions obtained from a. chica for determination ... | 2014 | 24818162 |
| antileishmanial activity of the estrogen receptor modulator raloxifene. | the treatment of leishmaniasis relies mostly on parenteral drugs with potentially serious adverse effects. additionally, parasite resistance in the treatment of leishmaniasis has been demonstrated for the majority of drugs available, making the search for more effective and less toxic drugs and treatment regimens a priority for the control of leishmaniasis. the aims of this study were to evaluate the antileishmanial activity of raloxifene in vitro and in vivo and to investigate its mechanism of ... | 2014 | 24810565 |
| in vitro and in vivo antileishmania activity of sesquiterpene lactone-rich dichloromethane fraction obtained from tanacetum parthenium (l.) schultz-bip. | the discovery of new treatments for neglected diseases, including leishmaniasis, is a substantial challenge for scientific research. plant extracts have shown potential in the selective treatment of tropical diseases. the present study evaluated the in vitro and in vivo antileishmania effects of a sesquiterpene lactone-rich dichloromethane fraction (df) obtained from the aerial parts of tanacetum parthenium (l.) schultz-bip. in vitro studies of the df indicated an ic50 of 2.40±0.76 μg ml(-1) aga ... | 2014 | 24810433 |
| periodate-oxidized atp modulates macrophage functions during infection with leishmania amazonensis. | previously, we showed that treating macrophages with atp impairs the intracellular growth of leishmania amazonensis, and that the p2x7 purinergic receptor is overexpressed during leishmaniasis. in the present study, we directly evaluated the effect of periodate-oxidized atp (oatp) on parasite control in leishmania-infected macrophages. we found that oatp impaired the attachment/entrance of l. amazonensis promastigotes to c57bl/6 mouse macrophages in a p2x7 receptor-independent manner, as macroph ... | 2014 | 24804957 |
| leishmanicidal evaluation of tetrahydroprotoberberine and spirocyclic erythrina-alkaloids. | leishmaniasis is one of the world's most problematic diseases in developing countries. traditional medicines to treat leishmaniasis have serious side effects, as well as significant parasite resistance problems. in this work, two alkaloids 1 and 2 were obtained from corydalis govaniana wall and seven alkaloids 3-9, were obtained from erythrina verna. the structures of the compounds were confirmed by mass spectrometry and 1d- and 2d-nmr spectroscopy. the leishmanicidal activity of compounds 1-9 a ... | 2014 | 24802983 |
| antileishmanial activity of essential oil from chenopodium ambrosioides and its main components against experimental cutaneous leishmaniasis in balb/c mice. | chenopodium ambrosioides have been used during centuries by native people to treat parasitic diseases. | 2014 | 24768411 |
| leishmania amazonensis promastigotes in 3d collagen i culture: an in vitro physiological environment for the study of extracellular matrix and host cell interactions. | leishmania amazonensis is the causative agent of american cutaneous leishmaniasis, an important neglected tropical disease. once leishmania amazonensis is inoculated into the human host, promastigotes are exposed to the extracellular matrix (ecm) of the dermis. however, little is known about the interaction between the ecm and leishmania promastigotes. in this study we established l. amazonensis promastigote culture in a three-dimensional (3d) environment mainly composed of collagen i (col i). t ... | 2014 | 24765565 |
| role of protein kinase r in the killing of leishmania major by macrophages in response to neutrophil elastase and tlr4 via tnfα and ifnβ. | in cutaneous leishmaniasis, leishmania amazonensis activates macrophage double-stranded, rna-activated protein kinase r (pkr) to promote parasite growth. in our study, leishmania major grew normally in raw cells, raw-expressing dominant-negative pkr (pkr-dn) cells, and macrophages of pkr-knockout mice, revealing that pkr is dispensable for l. major growth in macrophages. pkr activation in infected macrophages with poly i:c resulted in parasite death. fifty percent of l. major-knockout lines for ... | 2014 | 24732131 |
| leukotriene b4 modulates p2x7 receptor-mediated leishmania amazonensis elimination in murine macrophages. | atp is an important signaling molecule in the immune system, and it is able to bind the p2x7 purinergic receptor. recently, our group showed that atp-treated macrophages eliminate leishmania amazonensis. it has been reported that leukotriene b4 (ltb4) reduces the parasitic load of infected macrophages. additionally, it has been demonstrated that the p2x7 receptor can induce pla2 activation and arachidonic acid mobilization. based on these findings, we investigated whether ltb4 is produced upon p ... | 2014 | 24729618 |
| antiparasitic activities of novel ruthenium/lapachol complexes. | the present study describes the synthesis, characterization, antileishmanial and antiplasmodial activities of novel diimine/(2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), 4,4'-methylbipyridine (me-bipy) and 4,4'-methoxybipyridine (meo-bipy)/phosphine/ruthenium(ii) complexes containing lapachol (lap, 2-hydroxy-3-(3-33 methyl-2-buthenyl)-1,4-naphthoquinone) as bidentate ligand. the [ru(lap)(pph3)2(bipy)]pf6 (1), [ru(lap)(pph3)2(me-bipy)]pf6 (2), [ru(lap)(pph3)2(meo-bipy)]pf6(3) and[ru(lap)(p ... | 2014 | 24727183 |
| purification and biochemical characterization of three myotoxins from bothrops mattogrossensis snake venom with toxicity against leishmania and tumor cells. | bothrops mattogrossensis snake is widely distributed throughout eastern south america and is responsible for snakebites in this region. this paper reports the purification and biochemical characterization of three new phospholipases a2 (pla2s), one of which is presumably an enzymatically active asp49 and two are very likely enzymatically inactive lys49 pla2 homologues. the purification was obtained after two chromatographic steps on ion exchange and reverse phase column. the 2d sds-page analysis ... | 2014 | 24724078 |
| in vitro cytokines profile and ultrastructural changes of microglia and macrophages following interaction with leishmania. | in the present study, we assessed morphological changes and cytokine production after in vitro interaction with causative agents of american cutaneous leishmaniasis and compared the microglia and macrophage immune responses. cultures of microglia and macrophages infected with stationary-phase promastigotes of leishmania (viannia) shawi, leishmania (viannia) braziliensis or leishmania (leishmania) amazonensis were evaluated 24, 48 and 72 h after interaction. macrophages only presented the classic ... | 2014 | 24717447 |
| in vitro and in vivo efficacy of novel flavonoid dimers against cutaneous leishmaniasis. | treatment of leishmaniasis by chemotherapy remains a challenge because of limited efficacy, toxic side effects, and drug resistance. we previously reported that synthetic flavonoid dimers have potent antipromastigote and antiamastigote activity against leishmania donovani, the causative agent of visceral leishmaniasis. here, we further investigate their leishmanicidal activities against cutaneous leishmania species. one of the flavonoid dimers (compound 39) has marked antipromastigote (50% inhib ... | 2014 | 24687505 |
| correlation between glucose uptake and membrane potential in leishmania parasites isolated from dcl patients with therapeutic failure: a proof of concept. | besides infection with drug-resistant parasites, therapeutic failure in leishmaniasis may be caused by altered drug pharmacokinetics, re-infection, and host immunologic compromise. our aim has been to evaluate if relapses that occur in patients suffering from diffuse cutaneous leishmaniasis (dcl) associate with changes in the fitness of infecting organisms. therefore, in isolates from patients suffering dcl, we correlated glucose uptake and plasma membrane potential and compared the results with ... | 2014 | 24671239 |
| activity of anti-cancer protein kinase inhibitors against leishmania spp. | there is an urgent need to develop new and effective treatments for poverty-related neglected diseases. in light of the time required to bring a new drug to market and the cost involved (10-15 years, >1 billion us$), one approach to identifying new treatments for diseases like leishmaniasis is to evaluate drugs that are already registered for the treatment of other diseases. this paper describes the anti-leishmanial activities of 10 fda-approved protein kinase inhibitors already available for th ... | 2014 | 24668412 |
| immunization with antigenic extracts of leishmania associated with montanide isa 763 adjuvant induces partial protection in balb/c mice against leishmania (leishmania) amazonensis infection. | a proper adjuvant has a relevant role in vaccine formulations to generate an effective immune response. in this study, total leishmania antigen (tla) formulated with montanide isa 763 or r848 as adjuvants were evaluated as a first generation leishmania vaccine in a murine model. | 2016 | 24662018 |
| understanding the mechanisms controlling leishmania amazonensis infection in vitro: the role of ltb4 derived from human neutrophils. | neutrophils are rapidly recruited to the site of leishmania infection and play an active role in capturing and killing parasites. they are the main source of leukotriene b4 (ltb4), a potent proinflammatory lipid mediator. however, the role of ltb4 in neutrophil infection by leishmania amazonensis is not clear. in this study, we show that l. amazonensis or its lipophosphoglycan can induce neutrophil activation, degranulation, and ltb4 production. using pharmacological inhibitors of leukotriene sy ... | 2014 | 24634497 |
| novel targeting using nanoparticles: an approach to the development of an effective anti-leishmanial drug-delivery system. | the study reported here aimed to develop an optimized nanoparticle delivery system for amphotericin b (ampb) using a polyelectrolyte complexation technique. for this, two oppositely charged polymers presenting anti-leishmanial activity - chitosan (cs) and chondroitin sulfate (chs) - were used: cs as a positively charged polymer and chs as a negatively charged polymer. the chitosan (nq) nanoparticles, chitosan-chondroitin sulfate (nqc) nanoparticles, and chitosan-chondroitin sulfate-amphotericin ... | 2014 | 24627630 |
| identification and characterization of new leishmania promastigote surface antigens, lapsa-38s and lipsa-50s, as major immunodominant excreted/secreted components of l. amazonensis and l. infantum. | we have previously demonstrated that sera from dogs vaccinated with excreted/secreted antigens (esa) of leishmania infantum promastigotes (liesap) mainly recognized an immunodominant antigen of 54 kda. an anti-liesap-specific igg2 humoral response was observed and associated to th1-type response in vaccinated dogs. this response was highly correlated with a long-lasting and strong liesap-vaccine protection toward l. infantum experimental infection. in addition, it was also shown that dogs from t ... | 2014 | 24614507 |
| miltefosine increases lipid and protein dynamics in leishmania amazonensis membranes at concentrations similar to those needed for cytotoxicity activity. | miltefosine (mt) is a membrane-active alkylphospholipid licensed for the topical treatment of breast cancer skin metastases and the oral treatment of leishmaniasis, although its mechanism of action remains unclear. electron paramagnetic resonance (epr) spectroscopy of a spin-labeled lipid and a thiol-specific spin label in the plasma membrane of leishmania promastigotes showed that mt causes dramatic increases in membrane dynamics. although these alterations can be detected using a spin-labeled ... | 2014 | 24614380 |
| combination therapy with tamoxifen and amphotericin b in experimental cutaneous leishmaniasis. | leishmaniasis chemotherapy remains very challenging. the high cost of active drugs, along with the severity of their side effects and the increasing failure rate of the current therapeutic schemes, calls for the discovery of new active drugs and schemes of treatment. the use of combination therapy has gained much attention in recent years as a possible strategy for overcoming the various shortcomings in the present arsenal. we recently described the effectiveness of tamoxifen in murine models of ... | 2014 | 24550333 |
| potential therapeutic use of herbal extracts in trypanosomiasis. | the aim of the present study was to evaluate the effects of crude extracts from handroanthus impetiginosa, ageratum conyzoides, and ruta graveolens on leishmania amazonensis and trypanosoma cruzi infection in vitro. the results showed that the extracts caused significant toxicity in promastigotes and trypomastigotes. a significant decrease in the rate of cell invasion by pretreated trypomastigotes and promastigotes was also observed. the extracts caused a significant reduction of the multiplicat ... | 2014 | 24548158 |
| molecular characterization of the mrpa transporter and antimony uptake in four new world leishmania spp. susceptible and resistant to antimony. | atp-binding cassette (abc) transporters have been associated with drug resistance in various diseases. the mrpa gene, a transporter of abcc subfamily, is involved in the resistance by sequestering metal-thiol conjugates in intracellular vesicles of leishmania parasite. in this study, we performed the molecular characterization of the mrpa transporter, analysis of p-glycoprotein (pgp) and aquaglyceroporin-1 (aqp1) expression, and determination of antimony level in antimony-susceptible and -resist ... | 2013 | 24533304 |
| isolation of arginase inhibitors from the bioactivity-guided fractionation of byrsonima coccolobifolia leaves and stems. | byrsonima coccolobifolia leaf and stem extracts were studied in the search for possible leishmanicidal compounds using arginase (arg) from leishmania amazonensis as a molecular target. flavonoids 1b, 1e-1g, 2a, 2b, and 2d-2f showed significant inhibitory activity, with ic50 values ranging from 0.9 to 4.8 μm. the kinetics of the most active compounds were determined. flavonoids 1e, 1f, 2a, 2b, and 2e were characterized as noncompetitive inhibitors of arg with dissociation constants (ki) ranging f ... | 2014 | 24521209 |
| sod1 plasma level as a biomarker for therapeutic failure in cutaneous leishmaniasis. | we show that increased plasma superoxide dismutase 1 (sod1) levels are statistically significant predictors of the failure of pentavalent antimony treatment for cutaneous leishmaniasis caused by leishmania braziliensis. in leishmania amazonensis-infected patients, host sod1 levels can be used to discriminate between localized and drug-resistant diffuse cutaneous leishmaniasis. using in situ transcriptomics (ncounter), we demonstrate a significant positive correlation between host sod1 and interf ... | 2014 | 24511100 |
| the calpain inhibitor mdl28170 induces the expression of apoptotic markers in leishmania amazonensis promastigotes. | human cutaneous leishmaniasis is caused by distinct species, including leishmania amazonensis. treatment of cutaneous leishmaniasis is far from satisfactory due to increases in drug resistance and relapses, and toxicity of compounds to the host. as a consequence for this situation, the development of new leishmanicidal drugs and the search of new targets in the parasite biology are important goals. | 2014 | 24498160 |
| leishmania braziliensis and leishmania amazonensis amastigote extracts differ in their enhancement effect on leishmania infection when injected intradermally. | it has been reported that repeated intravenous injections of a relatively large amount of leishmania amazonensis amastigote extract (lae) in balb/c mice exacerbates the infection of these mice by leishmania braziliensis. the identification of the extract active principle(s) through physicochemical purification often involves dilution and losses of protein in the course of successive purification procedures. the large amount of the extract required to induce the phenomenon, therefore, hinders the ... | 2014 | 24484604 |
| targeted extracellular signal-regulated kinase activation mediated by leishmania amazonensis requires mp1 scaffold. | leishmania amazonensis infection promotes alteration of host cellular signaling and intracellular parasite survival, but specific mechanisms are poorly understood. we previously demonstrated that l. amazonensis infection of dendritic cells (dc) activated extracellular signal-regulated kinase (erk), an map-kinase kinase kinase, leading to altered dc maturation and non-healing cutaneous leishmaniasis. studies using growth factors and cell lines have shown that targeted, robust, intracellular phosp ... | 2014 | 24463270 |
| excreted leishmania peruviana and leishmania amazonensis iron-superoxide dismutase purification: specific antibody detection in colombian patients with cutaneous leishmaniasis. | leishmania sp. survival in the vertebrate host depends on the host macrophage immune response as well as on the parasite's defense against free radicals. iron-superoxide dismutase (fe-sod) is a key antioxidant enzyme that contributes to radical superoxide dismutation, preventing the disease from surging and propagating itself. leishmania sp. has various fe-sod isoforms, one of which (fe-sode) is excreted into the medium and, being highly immunogenic, can be considered a very good molecular marke ... | 2014 | 24440468 |
| dynamic identification of h2 epitopes from leishmania (leishmania) amazonensis cysteine proteinase b with potential immune activity during murine infection. | peptides from the cooh-terminal extension of cysteine proteinase b from leishmania (leishmania) amazonensis (cyspep) can modulate immune responses in vertebrate hosts. with this hypothesis as base, we used the online analysis tool syfpeithi to predict seven epitopes from this region with potential to bind h2 proteins. we performed proliferation tests and quantified reactive t lymphocytes applying a cytometry analysis, using samples from draining lymph node of lesions from l. (l.) amazonensis-inf ... | 2014 | 24436127 |
| complexes of different nitrogen donor heterocyclic ligands with sbcl3 and phsbcl2 as potential antileishmanial agents against sb(iii)-sensitive and -resistant parasites. | novel trivalent antimony complexes with the nitrogen donor heterocyclic ligand 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) or dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) have been synthesized by the reaction with sbcl3 or phsbcl2. the crystal structures of [sb(phen)cl3] and [phsb(phen)cl2]ch3cooh were determined and shown to adopt a distorted square pyramid geometry with a five-coordinated sb center. surprisingly, all the complexes, the ligands and phsbcl2 showed very high antileishmanial ac ... | 2014 | 24412095 |
| in vitro interaction between surfacen® and surfactant protein a against leishmania amazonensis. | leishmaniasis is caused by a parasite of the leishmania genus, affecting more than 12 million people in 98 countries. the control of leishmaniasis remains a serious problem. there are currently no vaccines for leishmaniasis. the drugs available are toxic, expensive and frequently ineffective. the in vitro activity of surfacen® and sp-a against leishmania amazonensis was evaluated. the combination of both products resulted in a synergic pharmacology effect, demonstrated by a fractional inhibitory ... | 2013 | 24401208 |
| unsymmetrical 1,5-diaryl-3-oxo-1,4-pentadienyls and their evaluation as antiparasitic agents. | in this work the synthesis and antiparasitical activity of new 1,5-diaryl-3-oxo-1,4-pentadienyl derivatives are described. first, compounds 1a, 1b, 1c and 1d were prepared by acid-catalyzed aldol reaction between 2-butanone and benzaldehyde, anisaldehyde, p-n,n-dimethylaminobenzaldehyde and p-nitrobenzaldehyde. reacting each of the methyl ketones 1a, 1b, 1c and 1d with the p-substituted benzaldehydes under basic-catalyzed aldol reaction, we further prepared compounds 2a-2p. all twenty compounds ... | 2014 | 24398381 |
| cross-protective effect of a combined l5 plus l3 leishmania major ribosomal protein based vaccine combined with a th1 adjuvant in murine cutaneous and visceral leishmaniasis. | two leishmania major ribosomal proteins l3 (lml3) and l5 (lml5) have been described as protective molecules against cutaneous leishmaniasis due to infection with l. major and leishmania braziliensis in balb/c mice when immunized with a th1 adjuvant (non-methylated cpg-oligodeoxynucleotides; cpg-odn). in the present study we analyzed the cross-protective efficacy of an lml3-lml5-cpg odn combined vaccine against infection with leishmania amazonensis and leishmania chagasi (syn. leishmania infantum ... | 2014 | 24382098 |
| in vitro activity of the antifungal azoles itraconazole and posaconazole against leishmania amazonensis. | leishmaniasis, caused by protozoan parasites of the leishmania genus, is one of the most prevalent neglected tropical diseases. it is endemic in 98 countries, causing considerable morbidity and mortality. pentavalent antimonials are the first line of treatment for leishmaniasis except in india. in resistant cases, miltefosine, amphotericin b and pentamidine are used. these treatments are unsatisfactory due to toxicity, limited efficacy, high cost and difficult administration. thus, there is an u ... | 2013 | 24376670 |
| synthesis and evaluation of the antiparasitic activity of bis-(arylmethylidene) cycloalkanones. | a series of bis-(arylmethylidene)-cycloalkanones was synthesized by cross-aldol condensation. the activity of the compounds was evaluated against amastigotes forms of trypanosoma cruzi and promastigotes forms of leishmania amazonensis. the cytotoxicity of the active compounds on uninfected fibroblasts or macrophages was established in vitro to evaluate the selectivity of their antiparasitic effects. six compounds displayed trypanocidal activity against amastigotes intracellular forms of t. cruzi ... | 2014 | 24321832 |
| leishmania amazonensis: characterization of an ecto-pyrophosphatase activity. | several ecto-enzymatic activities have been described in the plasma membrane of the protozoan leishmania amazonensis, which is the major etiological agent of diffuse cutaneous leishmaniasis in south america. these enzymes, including ecto-phosphatases, contribute to the survival of the parasite by participating in phosphate metabolism. this work identifies and characterizes the extracellular hydrolysis of inorganic pyrophosphate related to an ecto-pyrophosphatase activity of the promastigote form ... | 2014 | 24316462 |
| in vitro antiparasitic activity and chemical composition of the essential oil obtained from the fruits of piper cubeba. | protozoans of the trypanosomatid family cause the neglected tropical diseases leishmaniasis and trypanosomiasis, for which few drugs are available. in this context our group has recently reported that the essential oil obtained by steam distillation of the fruits of piper cubeba is active against schistosoma mansoni. therefore, we have investigated the in vitro effects of the essential oil against the trypomastigote and amastigote forms of trypanosoma cruzi isolated from an llcmk₂ cell line cult ... | 2013 | 24288276 |
| leishmania amazonensis promastigotes present two distinct modes of nucleus and kinetoplast segregation during cell cycle. | here, we show the morphological events associated with organelle segregation and their timing in the cell cycle of a reference strain of leishmania (l.) amazonensis promastigotes, the main causative agent of tegumentary leishmaniasis in the americas. we show evidences that during the cell cycle, l. amazonensis promastigotes present two distinct modes of nucleus and kinetoplast segregation, which occur in different temporal order in different proportions of cells. we used dapi-staining and edu-la ... | 2013 | 24278433 |
| a2 and other visceralizing proteins of leishmania: role in pathogenesis and application for vaccine development. | visceral leishmaniasis is a re-emergent disease and a significant cause of morbidity worldwide. amongst the more than 20 leishmania species, leishmania donovani, leishmania infantum and more rarely leishmania amazonensis are associated with visceral leishmaniasis. a major question in leishmaniasis research is how these species migrate to and infect visceral organs whereas other species such as leishmania major and leishmania braziliensis remain in the skin, causing tegumentary leishmaniasis. her ... | 2014 | 24264241 |
| brazilian brown propolis elicits antileishmanial effect against promastigote and amastigote forms of leishmania amazonensis. | propolis is a complex matrix of chemical constituents extracted from plants and produced by bees which is used in folk medicine due to its several pharmacological properties. its chemical composition varies according to the region where it is produced. this work has studied the antileishmanial activity and cytotoxicity of brown propolis (bp) originating from the semi-arid region of piauí, brazil. the bp showed significant inhibition of the leishmania amazonensis promastigotes growth as well as b ... | 2014 | 24261482 |
| inhibition of leishmania (leishmania) amazonensis and rat arginases by green tea egcg, (+)-catechin and (-)-epicatechin: a comparative structural analysis of enzyme-inhibitor interactions. | epigallocatechin-3-gallate (egcg), a dietary polyphenol (flavanol) from green tea, possesses leishmanicidal and antitrypanosomal activity. mitochondrial damage was observed in leishmania treated with egcg, and it contributed to the lethal effect. however, the molecular target has not been defined. in this study, egcg, (+)-catechin and (-)-epicatechin were tested against recombinant arginase from leishmania amazonensis (arg-l) and rat liver arginase (arg-1). the compounds inhibit arg-l and arg-1 ... | 2013 | 24260115 |
| genotoxicity and antileishmanial activity evaluation of physalis angulata concentrated ethanolic extract. | antileishmanial in vitro tests, as well as ames and micronucleus assays were performed with a concentrated ethanolic extract of physalis angulata (eepa) results: eepa did not present mutagenic effect in salmonella typhimurium strains at concentration reaching 3000 μg/plate and did not induce mutagenic effects after two oral administrations with a 24h interval at a dose level of 2000 mg/kg. eepa presented antileishmanial activity and presented an ic₅₀ value of 5.35 ± 2.50 μg/ml and 4.50 ± 1.17 μg ... | 2013 | 24231691 |
| synthetic oxoisoaporphine alkaloids: in vitro, in vivo and in silico assessment of antileishmanial activities. | leishmaniasis is a growing health problem worldwide. as there are certain drawbacks with the drugs currently used to treat human leishmaniasis and resistance to these drugs is emerging, there is a need to develop novel antileishmanial compounds, among which isoquinoline alkaloids are promising candidates. in this study, 18 novel oxoisoaporphine derivatives were synthesized and their possible antileishmanial activity was evaluated. the in vitro activity of these derivatives against leishmania ama ... | 2013 | 24204870 |
| strychnos pseudoquina and its purified compounds present an effective in vitro antileishmanial activity. | the development of new and cost-effective alternative therapeutic strategies to treat leishmaniasis has become a high priority. in the present study, the antileishmanial activity of strychnos pseudoquina st. hil. was investigated and pure compounds that presented this biological effect were isolated. an ethyl acetate extract was prepared, and it proved to be effective against leishmania amazonensis. a bioactivity-guided fractionation was performed, and two flavonoids were identified, quercetin 3 ... | 2013 | 24194781 |
| essential oil from chenopodium ambrosioides and main components: activity against leishmania, their mitochondria and other microorganisms. | chenopodium ambrosioides is an aromatic herb used by native people to treat parasitic diseases. the aim of this work is to compare the in vitro anti-leishmanial activity of the essential oil (eo) from c. ambrosioides and its major components (ascaridole, carvacrol and caryophyllene oxide) and study their mechanism of action and activity against a panel of microorganism. antileishmanial activity and cytotoxicity of the eo and major components was study. in addition, experiments to elucidate the m ... | 2014 | 24184772 |
| treatment with triterpenic fraction purified from baccharis uncinella leaves inhibits leishmania (leishmania) amazonensis spreading and improves th1 immune response in infected mice. | 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 mac ... | 2014 | 24173812 |
| in vitro and in vivo antileishmanial and trypanocidal studies of new n-benzene- and n-naphthalenesulfonamide derivatives. | we report in vivo and in vitro antileishmanial and trypanocidal activities of a new series of n-substituted benzene and naphthalenesulfonamides 1-15. compounds 1-15 were screened in vitro against leishmania infantum , leishmania braziliensis , leishmania guyanensis , leishmania amazonensis , and trypanosoma cruzi . sulfonamides 6e, 10b, and 10d displayed remarkable activity and selectivity toward t. cruzi epimastigotes and amastigotes. 6e showed significant trypanocidal activity on parasitemia i ... | 2013 | 24151871 |
| synthesis and activity of novel tetrazole compounds and their pyrazole-4-carbonitrile precursors against leishmania spp. | a new series of 5-(1-aryl-3-methyl-1h-pyrazol-4-yl)-1h-tetrazole derivatives (4a-m) and their precursor 1-aryl-3-methyl-1h-pyrazole-4-carbonitriles (3a-m) were synthesized and evaluated as antileishmanials against leishmania braziliensis and leishmania amazonensis promastigotes in vitro. in parallel, the cytotoxicity of these compounds was evaluated on the raw 264.7 cell line. the results showed that among the assayed compounds the substituted 3-chlorophenyl (4a) (ic50/24h=15±0.14 μm) and 3,4-di ... | 2013 | 24125880 |
| constitutive mosaic aneuploidy is a unique genetic feature widespread in the leishmania genus. | using fluorescence in situ hybridization, we determined the ploidy of four species of leishmania: leishmania infantum, leishmania donovani, leishmania tropica and leishmania amazonensis. we found that each cell in a strain possesses a combination of mono-, di- and trisomies for all chromosomes; ploidy patterns were different among all strains/species. these results extend those we previously described in leishmania major, demonstrating that mosaic aneuploidy is a genetic feature widespread to th ... | 2014 | 24120456 |
| effectiveness of novel 5-(5-amino-1-aryl-1h-pyrazol-4-yl)-1h-tetrazole derivatives against promastigotes and amastigotes of leishmania amazonensis. | in this research, a series of substituted 5-(5-amino-1-aryl-1h-pyrazol-4-yl)-1h-tetrazoles were synthesized and evaluated for in vitro antileishmanial activity. among the derivatives, examined compounds 3b and 3l exhibited promising activity against promastigotes and amastigotes forms of leishmania amazonensis. the cytotoxicity of these compounds was evaluated on murine cells, giving access to the corresponding selectivity index (si). | 2014 | 24119090 |