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  1. Article: Insights from Leishmania (Viannia) guyanensis in vitro behavior and intercellular communication

    Pereira, Luiza O. R. / Sousa, Cíntia S. / Ramos, Hellen C. P. / Torres-Santos, Eduardo C. / Pinheiro, Liliane S. / Alves, Marcelo R. / Cuervo, Patricia / Romero, Gustavo A. Sierra / Boité, Mariana C. / Porrozzi, Renato / Cupolillo, Elisa

    Parasites & vectors. 2021 Dec., v. 14, no. 1

    2021  

    Abstract: BACKGROUND: Pentavalent antimonial-based chemotherapy is the first-line approach for leishmaniasis treatment and disease control. Nevertheless antimony-resistant parasites have been reported in some endemic regions. Treatment refractoriness is complex ... ...

    Abstract BACKGROUND: Pentavalent antimonial-based chemotherapy is the first-line approach for leishmaniasis treatment and disease control. Nevertheless antimony-resistant parasites have been reported in some endemic regions. Treatment refractoriness is complex and is associated with patient- and parasite-related variables. Although amastigotes are the parasite stage in the vertebrate host and, thus, exposed to the drug, the stress caused by trivalent antimony in promastigotes has been shown to promote significant modification in expression of several genes involved in various biological processes, which will ultimately affect parasite behavior. Leishmania (Viannia) guyanensis is one of the main etiological agents in the Amazon Basin region, with a high relapse rate (approximately 25%). METHODS: Herein, we conducted several in vitro analyses with L. (V.) guyanensis strains derived from cured and refractory patients after treatment with standardized antimonial therapeutic schemes, in addition to a drug-resistant in vitro-selected strain. Drug sensitivity assessed through Sb(III) half-maximal inhibitory concentration (IC₅₀) assays, growth patterns (with and without drug pressure) and metacyclic-like percentages were determined for all strains and compared to treatment outcomes. Finally, co-cultivation without intercellular contact was followed by parasitic density and Sb(III) IC₅₀ measurements. RESULTS: Poor treatment response was correlated with increased Sb(III) IC₅₀ values. The decrease in drug sensitivity was associated with a reduced cell replication rate, increased in vitro growth ability, and higher metacyclic-like proportion. Additionally, in vitro co-cultivation assays demonstrated that intercellular communication enabled lower drug sensitivity and enhanced in vitro growth ability, regardless of direct cell contact. CONCLUSIONS: Data concerning drug sensitivity in the Viannia subgenus are emerging, and L. (V.) guyanensis plays a pivotal epidemiological role in Latin America. Therefore, investigating the parasitic features potentially related to relapses is urgent. Altogether, the data presented here indicate that all tested strains of L. (V.) guyanensis displayed an association between treatment outcome and in vitro parameters, especially the drug sensitivity. Remarkably, sharing enhanced growth ability and decreased drug sensitivity, without intercellular communication, were demonstrated.
    Keywords amastigotes ; antimony ; basins ; cell communication ; coculture ; disease control ; drug resistance ; drug therapy ; drugs ; leishmaniasis ; parasites ; promastigotes ; relapse ; vertebrates ; Latin America
    Language English
    Dates of publication 2021-12
    Size p. 556.
    Publishing place BioMed Central
    Document type Article
    ZDB-ID 2409480-8
    ISSN 1756-3305
    ISSN 1756-3305
    DOI 10.1186/s13071-021-05057-x
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  2. Article ; Online: Insights from Leishmania (Viannia) guyanensis in vitro behavior and intercellular communication.

    Pereira, Luiza O R / Sousa, Cíntia S / Ramos, Hellen C P / Torres-Santos, Eduardo C / Pinheiro, Liliane S / Alves, Marcelo R / Cuervo, Patricia / Romero, Gustavo A Sierra / Boité, Mariana C / Porrozzi, Renato / Cupolillo, Elisa

    Parasites & vectors

    2021  Volume 14, Issue 1, Page(s) 556

    Abstract: Background: Pentavalent antimonial-based chemotherapy is the first-line approach for leishmaniasis treatment and disease control. Nevertheless antimony-resistant parasites have been reported in some endemic regions. Treatment refractoriness is complex ... ...

    Abstract Background: Pentavalent antimonial-based chemotherapy is the first-line approach for leishmaniasis treatment and disease control. Nevertheless antimony-resistant parasites have been reported in some endemic regions. Treatment refractoriness is complex and is associated with patient- and parasite-related variables. Although amastigotes are the parasite stage in the vertebrate host and, thus, exposed to the drug, the stress caused by trivalent antimony in promastigotes has been shown to promote significant modification in expression of several genes involved in various biological processes, which will ultimately affect parasite behavior. Leishmania (Viannia) guyanensis is one of the main etiological agents in the Amazon Basin region, with a high relapse rate (approximately 25%).
    Methods: Herein, we conducted several in vitro analyses with L. (V.) guyanensis strains derived from cured and refractory patients after treatment with standardized antimonial therapeutic schemes, in addition to a drug-resistant in vitro-selected strain. Drug sensitivity assessed through Sb(III) half-maximal inhibitory concentration (IC
    Results: Poor treatment response was correlated with increased Sb(III) IC
    Conclusions: Data concerning drug sensitivity in the Viannia subgenus are emerging, and L. (V.) guyanensis plays a pivotal epidemiological role in Latin America. Therefore, investigating the parasitic features potentially related to relapses is urgent. Altogether, the data presented here indicate that all tested strains of L. (V.) guyanensis displayed an association between treatment outcome and in vitro parameters, especially the drug sensitivity. Remarkably, sharing enhanced growth ability and decreased drug sensitivity, without intercellular communication, were demonstrated.
    MeSH term(s) Antiprotozoal Agents/pharmacology ; Cell Communication ; Drug Resistance ; Humans ; Inhibitory Concentration 50 ; Latin America ; Leishmania guyanensis/drug effects ; Leishmania guyanensis/growth & development ; Leishmania guyanensis/physiology ; Leishmaniasis, Cutaneous/drug therapy ; Leishmaniasis, Cutaneous/parasitology
    Chemical Substances Antiprotozoal Agents
    Language English
    Publishing date 2021-10-28
    Publishing country England
    Document type Journal Article
    ZDB-ID 2409480-8
    ISSN 1756-3305 ; 1756-3305
    ISSN (online) 1756-3305
    ISSN 1756-3305
    DOI 10.1186/s13071-021-05057-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Unmasking the Amphotericin B Resistance Mechanisms in

    Silva, Laura N / Oliveira, Simone S C / Magalhães, Lucas B / Andrade Neto, Valter V / Torres-Santos, Eduardo C / Carvalho, Mariana D C / Pereira, Marcos D / Branquinha, Marta H / Santos, André L S

    ACS infectious diseases

    2020  Volume 6, Issue 5, Page(s) 1273–1282

    Abstract: The polyene amphotericin B (AMB) exerts a powerful and broad antifungal activity. AMB acts by (i) binding to ergosterol, leading to pore formation at the fungal plasma membrane with subsequent ion leakage, and (ii) inducing the intracellular accumulation ...

    Abstract The polyene amphotericin B (AMB) exerts a powerful and broad antifungal activity. AMB acts by (i) binding to ergosterol, leading to pore formation at the fungal plasma membrane with subsequent ion leakage, and (ii) inducing the intracellular accumulation of reactive oxygen species (ROS). Herein, we have deciphered the AMB resistance mechanisms in clinical isolates of
    MeSH term(s) Amphotericin B/pharmacology ; Antifungal Agents/pharmacology ; Candida/drug effects ; Candida/metabolism ; Drug Resistance, Fungal ; Humans ; Microbial Sensitivity Tests
    Chemical Substances Antifungal Agents ; Amphotericin B (7XU7A7DROE)
    Language English
    Publishing date 2020-04-14
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2373-8227
    ISSN (online) 2373-8227
    DOI 10.1021/acsinfecdis.0c00117
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Naphthoquinones and Derivatives for Chemotherapy: Perspectives and Limitations of their Anti-trypanosomatids Activities.

    Dantas-Pereira, Luíza / Cunha-Junior, Edézio F / Andrade-Neto, Valter V / Bower, John F / Jardim, Guilherme A M / da Silva Júnior, Eufrânio N / Torres-Santos, Eduardo C / Menna-Barreto, Rubem F S

    Current pharmaceutical design

    2020  Volume 27, Issue 15, Page(s) 1807–1824

    Abstract: Chagas disease, Sleeping sickness and Leishmaniasis, caused by trypanosomatids Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively, are considered neglected tropical diseases, and they especially affect impoverished populations in the ...

    Abstract Chagas disease, Sleeping sickness and Leishmaniasis, caused by trypanosomatids Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively, are considered neglected tropical diseases, and they especially affect impoverished populations in the developing world. The available chemotherapies are very limited, and a search for alternatives is still necessary. In folk medicine, natural naphthoquinones have been employed for the treatment of a great variety of illnesses, including parasitic infections. This review is focused on the anti-trypanosomatid activity and mechanistic analysis of naphthoquinones and derivatives. Among all the series of derivatives tested in vitro, naphthoquinone-derived 1,2,3-triazoles were very active on T. cruzi infective forms in blood bank conditions, as well as in amastigotes of Leishmania spp. naphthoquinones containing a CF
    MeSH term(s) Animals ; Chagas Disease ; Leishmaniasis ; Naphthoquinones/pharmacology ; Trypanosoma brucei brucei ; Trypanosoma cruzi
    Chemical Substances Naphthoquinones
    Language English
    Publishing date 2020-11-07
    Publishing country United Arab Emirates
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 1304236-1
    ISSN 1873-4286 ; 1381-6128
    ISSN (online) 1873-4286
    ISSN 1381-6128
    DOI 10.2174/1381612826666201109111802
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Design, Synthesis and Antileishmanial Activity of Naphthotriazolyl-4- Oxoquinolines.

    Oliveira, Vanessa G / Dos Santos Faiões, Viviane / Gonçalves, Gabrieli B R / Lima, Miriam F O / Boechat, Fernanda C S / Cunha, Anna C / de Andrade-Neto, Valter V / de C da Silva, Fernando / Torres-Santos, Eduardo C / de Souza, Maria Cecília B V

    Current topics in medicinal chemistry

    2018  Volume 18, Issue 17, Page(s) 1454–1464

    Abstract: Background: Leishmaniasis is a neglected public health problem caused by several protozoanspecies of the genus Leishmania. The therapeutic arsenal for treating leishmaniasis is quite limited, raising concerns about the occurrence of resistant strains. ... ...

    Abstract Background: Leishmaniasis is a neglected public health problem caused by several protozoanspecies of the genus Leishmania. The therapeutic arsenal for treating leishmaniasis is quite limited, raising concerns about the occurrence of resistant strains. Furthermore, most of these drugs were developed more than 70 years ago and suffer from poor efficacy and safety and are not well adapted to the needs of patients. Therefore, research on novel natural or synthetic compounds with antiparasitic activity is urgently needed. In this paper, we evaluated the effect and the mechanism of action of naphthotriazolyl-4-oxoquinolines on promastigotes and intracellular amastigotes of Leishmania amazonensis.
    Materials and methods: The naphthotriazolyl-4-oxoquinoline derivatives were obtained in good to moderate yields via the [3+2] cycloaddition reaction between 1,4-naphtoquinone and azido-4- oxoquinoline derivatives. HMPA at 100°C was established as the best solvent and temperature condition for this reaction. The structures of the compounds were confirmed by spectral analyses (infrared spectroscopy, one- and two-dimensional ¹H and ¹³C NMR spectroscopy, and high-resolution mass spectrometry). The compounds exhibited promising activities with IC50 values ranging from 0.7 to 2.0 µM against intracellular amastigotes of Leishmania amazonensis. The most selective compound was the Npentyl- substituted derivative, which showed a Selectivity Index (SI) of 8.6, making it less toxic than pentamidine (SI 4.5).
    Results: Our results demonstrated that all compounds, except the N-propyl-substituted derivative, induce ROS production by parasites early in the culture. As a proof of concept, we demonstrated that the most selective compound was able to interfere with sterol biosynthesis in L. amazonensis.
    Conclusion: The naphthotriazolyl-4-oxoquinoline derivatives were obtained in good to moderate yields. These conjugates have potent in vitro antileishmanial activity involving at least two different mechanisms of action, making them promising lead compounds for the development of new therapeutic alternatives for leishmaniasis.
    MeSH term(s) Antiprotozoal Agents/chemical synthesis ; Antiprotozoal Agents/chemistry ; Antiprotozoal Agents/pharmacology ; Dose-Response Relationship, Drug ; Drug Design ; Leishmania/drug effects ; Molecular Structure ; Parasitic Sensitivity Tests ; Quinolines/chemical synthesis ; Quinolines/chemistry ; Quinolines/pharmacology ; Structure-Activity Relationship
    Chemical Substances Antiprotozoal Agents ; Quinolines ; naphthotriazolyl-4- oxoquinoline
    Language English
    Publishing date 2018-10-01
    Publishing country United Arab Emirates
    Document type Journal Article
    ZDB-ID 2064823-6
    ISSN 1873-4294 ; 1568-0266
    ISSN (online) 1873-4294
    ISSN 1568-0266
    DOI 10.2174/1568026618666181002110116
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: HPLC analysis of supercritical carbon dioxide and compressed propane extracts from Piper amalago L. with antileishmanial activity.

    Carrara, Vanessa da Silva / Serra, Lara Zampar / Cardozo-Filho, Lúcio / Cunha, Edézio F / Torres-Santos, Eduardo C / Cortez, Diógenes Aparício Garcia

    Molecules (Basel, Switzerland)

    2011  Volume 17, Issue 1, Page(s) 15–33

    Abstract: Piper amalago L. leaves were extracted with supercritical carbon dioxide and compressed propane under different conditions, and with chloroform by the conventional maceration method. These methods were compared for the pyrrolidine alkaloid content. ... ...

    Abstract Piper amalago L. leaves were extracted with supercritical carbon dioxide and compressed propane under different conditions, and with chloroform by the conventional maceration method. These methods were compared for the pyrrolidine alkaloid content. Supercritical carbon dioxide (SFE-CO₂) at 313 K and 12.55 MPa showed the highest selectivity for the main compound (600.53 mg/g of extract). A gradient high-performance liquid chromatography (HPLC) method was developed and validated to quantify the alkaloid N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl]pyrrolidine in the extracts. The HPLC method showed linearity, precision and accuracy, allowing the quantitative analysis of the alkaloid in all the samples. All the extracts were tested against the promastigote and intracellular amastigote forms of Leishmania amazonensis. The antileishmanial activity was evaluated in terms of inhibitory concentration for 50% of protozoa (IC₅₀). The cytotoxicity was also evaluated against J774A1 macrophages, and the cytotoxic concentrations for 50% of macrophages were obtained (CC₅₀). The SFE-CO₂ (313 K; 12.55 MPa) extract showed the highest antileishmanial activity with the following IC₅₀ values of 16 and 7 µg/mL against the promastigotes and intracellular amastigotes forms, respectively. The extract showed low cytotoxicity with a CC₅₀ value of 93 µg/mL.
    MeSH term(s) Alkaloids/analysis ; Animals ; Antiprotozoal Agents/pharmacology ; Carbon Dioxide/analysis ; Chloroform/analysis ; Chromatography, High Pressure Liquid ; Chromatography, Supercritical Fluid ; Leishmania/drug effects ; Macrophages/drug effects ; Macrophages/parasitology ; Male ; Mice ; Mice, Inbred BALB C ; Parasitic Sensitivity Tests ; Piper/chemistry ; Plant Extracts/pharmacology ; Plant Leaves/chemistry ; Propane/analysis ; Reproducibility of Results ; Sensitivity and Specificity
    Chemical Substances Alkaloids ; Antiprotozoal Agents ; Plant Extracts ; Carbon Dioxide (142M471B3J) ; Chloroform (7V31YC746X) ; Propane (T75W9911L6)
    Language English
    Publishing date 2011-12-22
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules17010015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Pterocarpanquinone LQB-118 induces apoptosis in Leishmania (Viannia) braziliensis and controls lesions in infected hamsters.

    Costa, Luciana / Pinheiro, Roberta O / Dutra, Patrícia M L / Santos, Rosiane F / Cunha-Júnior, Edézio F / Torres-Santos, Eduardo C / da Silva, Alcides J M / Costa, Paulo R R / Da-Silva, Silvia A G

    PloS one

    2014  Volume 9, Issue 10, Page(s) e109672

    Abstract: 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 ... ...

    Abstract 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 promastigote and intracellular amastigote forms. The cell death induced by LQB-118 in the L. braziliensis promastigotes was analyzed using an annexin V-FITC/PI kit, the oxidative stress was evaluated by 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) and the ATP content by luminescence. In situ labeling of DNA fragments by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to investigate apoptosis in the intracellular amastigotes. L. braziliensis-infected hamsters were treated from the seventh day of infection with LQB-118 administered intralesionally (26 µg/kg/day, three times a week) or orally (4,3 mg/kg/day, five times a week) for eight weeks. LQB-118 was active against the L. braziliensis promastigotes and intracellular amastigotes, producing IC50 (50% inhibitory concentration) values of 3,4±0,1 and 7,5±0,8 µM, respectively. LQB-118 induced promastigote phosphatidylserine externalization accompanied by increased reactive oxygen species production and ATP depletion. Intracellular amastigote DNA fragmentation was also observed, without affecting the viability of macrophages. The treatment of L. braziliensis-infected hamsters with LQB-118, either orally or intralesionally, was effective in the control of lesion size, parasite load and increase intradermal reaction to parasite antigen. Taken together, these results show that the antileishmanial effect of LQB-118 extends to L. braziliensis in the hamster model, involves the induction of parasite apoptosis and shows promising therapeutic option by oral or local routes in leishmaniasis.
    MeSH term(s) Animals ; Antiprotozoal Agents/pharmacology ; Apoptosis/drug effects ; Cricetinae ; Female ; Leishmania braziliensis/drug effects ; Leishmaniasis, Cutaneous/parasitology ; Leishmaniasis, Cutaneous/pathology ; Macrophages/drug effects ; Macrophages/parasitology ; Membrane Potential, Mitochondrial/drug effects ; Mesocricetus ; Naphthoquinones/pharmacology ; Phosphatidylserines/metabolism ; Pterocarpans/pharmacology
    Chemical Substances Antiprotozoal Agents ; LQB 118 ; Naphthoquinones ; Phosphatidylserines ; Pterocarpans
    Language English
    Publishing date 2014-10-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0109672
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  8. Article ; Online: Effectiveness of novel 5-(5-amino-1-aryl-1H-pyrazol-4-yl)-1H-tetrazole derivatives against promastigotes and amastigotes of Leishmania amazonensis.

    dos Santos Faiões, Viviane / Leon, Leonor L / Canto-Cavalheiro, Marilene M / Torres-Santos, Eduardo C / Bernardino, Alice M R / Vegi, Percilene F / dos Santos, Maurício S

    Chemical biology & drug design

    2014  Volume 83, Issue 3, Page(s) 272–277

    Abstract: 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 ... ...

    Abstract 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).
    MeSH term(s) Animals ; Antiprotozoal Agents/chemical synthesis ; Antiprotozoal Agents/chemistry ; Antiprotozoal Agents/pharmacology ; Cell Line ; Cell Survival/drug effects ; Leishmania/drug effects ; Mice ; Mice, Inbred BALB C ; Tetrazoles/chemical synthesis ; Tetrazoles/chemistry ; Tetrazoles/pharmacology
    Chemical Substances Antiprotozoal Agents ; Tetrazoles
    Language English
    Publishing date 2014-03
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2216600-2
    ISSN 1747-0285 ; 1747-0277
    ISSN (online) 1747-0285
    ISSN 1747-0277
    DOI 10.1111/cbdd.12235
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: LDL uptake by Leishmania amazonensis: involvement of membrane lipid microdomains.

    De Cicco, Nuccia N T / Pereira, Miria G / Corrêa, José R / Andrade-Neto, Valter V / Saraiva, Felipe B / Chagas-Lima, Alessandra C / Gondim, Katia C / Torres-Santos, Eduardo C / Folly, Evelize / Saraiva, Elvira M / Cunha-E-Silva, Narcisa L / Soares, Maurilio J / Atella, Georgia C

    Experimental parasitology

    2012  Volume 130, Issue 4, Page(s) 330–340

    Abstract: Leishmania amazonensis lacks a de novo mechanism for cholesterol synthesis and therefore must scavenge this lipid from the host environment. In this study we show that the L. amazonensis takes up and metabolizes human LDL(1) particles in both a time and ... ...

    Abstract Leishmania amazonensis lacks a de novo mechanism for cholesterol synthesis and therefore must scavenge this lipid from the host environment. In this study we show that the L. amazonensis takes up and metabolizes human LDL(1) particles in both a time and dose-dependent manner. This mechanism implies the presence of a true LDL receptor because the uptake is blocked by both low temperature and by the excess of non-labelled LDL. This receptor is probably associated with specific microdomains in the membrane of the parasite, such as rafts, because this process is blocked by methyl-β-cyclodextrin (MCBD). Cholesteryl ester fluorescently-labeled LDL (BODIPY-cholesteryl-LDL) was used to follow the intracellular distribution of this lipid. After uptake it was localized in large compartments along the parasite body. The accumulation of LDL was analyzed by flow cytometry using FITC-labeled LDL particles. Together these data show for the first time that L. amazonensis is able to compensate for its lack of lipid synthesis through the use of a lipid importing machinery largely based on the uptake of LDL particles from the host. Understanding the details of the molecular events involved in this mechanism may lead to the identification of novel targets to block Leishmania infection in human hosts.
    MeSH term(s) Animals ; Cattle ; Cholesterol Esters/metabolism ; Endocytosis/physiology ; Esterification ; Flow Cytometry ; Fluorescein-5-isothiocyanate ; Fluorescent Dyes ; Humans ; Leishmania mexicana/drug effects ; Leishmania mexicana/growth & development ; Leishmania mexicana/metabolism ; Lipoproteins, HDL/blood ; Lipoproteins, HDL/metabolism ; Lipoproteins, LDL/blood ; Lipoproteins, LDL/metabolism ; Membrane Lipids/metabolism ; Membrane Microdomains/drug effects ; Membrane Microdomains/metabolism ; Mice ; Mice, Inbred BALB C ; Receptors, LDL/metabolism ; beta-Cyclodextrins/pharmacology
    Chemical Substances Cholesterol Esters ; Fluorescent Dyes ; Lipoproteins, HDL ; Lipoproteins, LDL ; Membrane Lipids ; Receptors, LDL ; beta-Cyclodextrins ; methyl-beta-cyclodextrin ; Fluorescein-5-isothiocyanate (I223NX31W9)
    Language English
    Publishing date 2012-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 391089-1
    ISSN 1090-2449 ; 0014-4894
    ISSN (online) 1090-2449
    ISSN 0014-4894
    DOI 10.1016/j.exppara.2012.02.014
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: LDL uptake by Leishmania amazonensis: Involvement of membrane lipid microdomains

    De Cicco, Nuccia N.T / Pereira, Miria G / Corrêa, José R / Andrade-Neto, Valter V / Saraiva, Felipe B / Chagas-Lima, Alessandra C / Gondim, Katia C / Torres-Santos, Eduardo C / Folly, Evelize / Saraiva, Elvira M / Cunha-e-Silva, Narcisa L / Soares, Maurilio J / Atella, Georgia C

    Experimental parasitology. 2012 Apr., v. 130, no. 4

    2012  

    Abstract: Leishmania amazonensis lacks a de novo mechanism for cholesterol synthesis and therefore must scavenge this lipid from the host environment. In this study we show that the L. amazonensis takes up and metabolizes human LDL¹ particles in both a time and ... ...

    Abstract Leishmania amazonensis lacks a de novo mechanism for cholesterol synthesis and therefore must scavenge this lipid from the host environment. In this study we show that the L. amazonensis takes up and metabolizes human LDL¹ particles in both a time and dose-dependent manner. This mechanism implies the presence of a true LDL receptor because the uptake is blocked by both low temperature and by the excess of non-labelled LDL. This receptor is probably associated with specific microdomains in the membrane of the parasite, such as rafts, because this process is blocked by methyl-β-cyclodextrin (MCBD). Cholesteryl ester fluorescently-labeled LDL (BODIPY-cholesteryl-LDL) was used to follow the intracellular distribution of this lipid. After uptake it was localized in large compartments along the parasite body. The accumulation of LDL was analyzed by flow cytometry using FITC-labeled LDL particles. Together these data show for the first time that L. amazonensis is able to compensate for its lack of lipid synthesis through the use of a lipid importing machinery largely based on the uptake of LDL particles from the host. Understanding the details of the molecular events involved in this mechanism may lead to the identification of novel targets to block Leishmania infection in human hosts.
    Keywords Leishmania amazonensis ; cholesterol ; dose response ; flow cytometry ; hosts ; human diseases ; humans ; low density lipoprotein ; parasites ; parasitology ; temperature
    Language English
    Dates of publication 2012-04
    Size p. 330-340.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 391089-1
    ISSN 0014-4894
    ISSN 0014-4894
    DOI 10.1016/j.exppara.2012.02.014
    Database NAL-Catalogue (AGRICOLA)

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