RESUMO
The lack of effective treatment options for an increasing number of cancer cases highlights the need for new anticancer therapeutic strategies. Immunotherapy mediated by Salmonella enterica Typhimurium is a promising anticancer treatment. Candidate strains for anticancer therapy must be attenuated while retaining their antitumor activity. Here, we investigated the attenuation and antitumor efficacy of two S. enterica Typhimurium mutants, ΔtolRA and ΔihfABpmi, in a murine melanoma model. Results showed high attenuation of ΔtolRA in the Galleria mellonella model, and invasion and survival in tumor cells. However, it showed weak antitumor effects in vitro and in vivo. Contrastingly, lower attenuation of the attenuated ΔihfABpmi strain resulted in regression of tumor mass in all mice, approximately 6 days after the first treatment. The therapeutic response induced by ΔihfABpmi was accompanied with macrophage accumulation of antitumor phenotype (M1) and significant increase in the mRNAs of proinflammatory mediators (TNF-α, IL-6, and iNOS) and an apoptosis inducer (Bax). Our findings indicate that the attenuated ΔihfABpmi exerts its antitumor activity by inducing macrophage infiltration or reprogramming the immunosuppressed tumor microenvironment to an activated state, suggesting that attenuated S. enterica Typhimurium strains based on nucleoid-associated protein genes deletion could be immunotherapeutic against cancer.
Assuntos
Salmonella typhimurium , Animais , Salmonella typhimurium/imunologia , Salmonella typhimurium/genética , Camundongos , Camundongos Endogâmicos C57BL , Melanoma/imunologia , Melanoma/genética , Melanoma/patologia , Imunoterapia/métodos , Macrófagos/imunologia , Macrófagos/metabolismo , Linhagem Celular Tumoral , Mutação , Feminino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Modelos Animais de DoençasRESUMO
Visceral leishmaniasis remains a serious public health issue, and Brazil was among the seven countries with the highest prevalence of this disease worldwide. The measures to control this disease are not easily developed, and the improvement of its diagnosis, surveillance, and control is still needed. This study aimed to carry out the polymerase chain reaction (PCR) diagnosis of Leishmania infantum in vector samples in some municipalities of the State of São Paulo, which included two municipalities with human disease transmission and two with dog transmission only. Vectors were collected in traps with luminous bait. Next, they were killed at -4 °C and kept in 70% alcohol. Groups of ten female insects (pools) were mashed on cation exchange paper (fine cellulose phosphate with 18 µEq/cm² ionic exchange capacity) for DNA extraction. The PCR was carried out to identify the natural infection of the Leishmania genus in female Lutzomyia longipalpis (Lu. Longipalpis). Out of the 3,880 Lu. longipalpis phlebotomines, 1060 were female and 2820 were male (3:1). The method used to extract the DNA in pools of ten phlebotomines and the PCR resulted in sensitivity, specificity, practicality, and faster analyses when compared to the individual analysis method. The procedure described can be used on a large scale in the leishmaniasis epidemiological surveillance, enabling a higher number of analyses and the optimization of human resources because the traditional diagnostic method is carried out via desiccation of the insect digestive system and microscopic examination, which is time-demanding and there is the need of manual skills.
RESUMO
A seleção natural é o principal mecanismo da evolução das espécies, e favorece fenótipos com defesas imunes efetivas contra patógenos. Entretanto, há uma grande variação das respostas imunes entre os indivíduos da espécie humana e a ocorrência de fenômenos imunopatológicos. A infecção com o vírus da família Coronaviridae, SARS-CoV-2, responsável pela doença conhecida como COVID-19, induz a respostas imunes inflamatórias exacerbadas e à tempestade de citocinas, nos casos graves. Nesta revisão discutiremos, à luz da Evolução, esse aparente paradoxo entre as respostas imunes, e os três principais fatores que contribuem para a manutenção dos fenótipos hiperativos: o custo-benefício das respostas imunes, a coevolução e a história de vida da espécie.
Natural selection is the main mechanism by which species evolve, and it favors phenotypes associated with an effective immune defense against pathogens. However, human immune responses and the occurrence of immunopathological phenomena vary considerably from individual to individual. Infection with SARSCoV- 2, a virus of the Coronaviridae family causing the disease known as COVID-19, induces exacerbated inflammatory immune responses and cytokine storm in severe cases. In this review, we discuss, in the light of Evolution, this apparent paradox between the immune responses and the 3 main factors contributing to the maintenance of hyperactive phenotypes: the cost-effectiveness of immune responses, coevolution, and the life history of the species.
Assuntos
HumanosRESUMO
The etiologic agents of visceral leishmaniasis are Leishmania infantum and Leishmania donovani. Despite the variety of drugs available to treat leishmaniasis, most lead to serious adverse effects, and resistance to these drugs has been reported. Currently, no leishmaniasis vaccine is available for humans. That is why the group developed transgenic L. infantum promastigote lines, which express toxic proteins after differentiation into amastigotes. That is why group developed the pFL-AMA plasmid and transfected it into L. Infantum promastigotes. This plasmid was expressed only in the amastigote form of the parasite. Sequences encoding toxic proteins (active bovine trypsin and egg avidin) were inserted in this plasmid, and the transfected parasites died after the differentiation process. In this study, two immunization protocols were performed in BALB/c mice: prime and prime-boost immunization prior to challenge with the wild-type L. infantum (WT). The parasite burdens in the spleen, liver, and bone marrow were evaluated to verify immunological protection. Histopathological analysis of the spleen and liver and the humoral immune response were also performed. The data showed that the parasite burden was reduced in prime-boosted mice in the spleen, liver, and bone marrow, indicating that mice immunized with two doses of the transfected parasites were satisfactorily protected. High levels of IgG, IgG1, and IgG2a antibodies were observed, as well as the presence of anti-inflammatory cytokine Interleukine-10 and pro-inflammatory cytokine Tumor Necrosis Factor-α (TNF-α) and Interferon-γ (IFN - γ) suggesting a Th1/Th2 mix response, in addition to the presence of multinucleated giant cells in the spleen and lymphocyte infiltration in the liver. Therefore, L. infantum transfected with a toxic plasmid is an excellent vaccine candidate against visceral leishmaniasis and the application of a boost before the challenge promotes greater protection against WT L. infantum infection.
Assuntos
Leishmania infantum , Leishmaniose Visceral , Parasitos , Vacinas Protozoárias , Animais , Anticorpos Antiprotozoários , Bovinos , Citocinas/metabolismo , Imunização , Leishmaniose Visceral/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , PlasmídeosRESUMO
Leishmaniasis is a neglected disease caused by species of the protozoan Leishmania. Leishmania (Viannia) braziliensis causes the cutaneous and mucocutaneous forms of the disease. Experimental cutaneous infection of mice is one of the most important preclinical research models of leishmaniasis. Here, we investigated the course of infection in mice inoculated with two reference strains of L. (V.) braziliensis (MHOM/BR/00/BA788 strain [BA] and MHOM/BR/94/H-3227 strain [CE]). Although both parasite strains induced detectable footpad lesions, BA-infected mice developed small non-ulcerated lesions that self-healed, whereas CE-infected mice developed small non-ulcerated lesions that did not regress. The parasites were detected in the footpad lesions, lymph nodes draining the site of inoculation, spleen, and bone marrow of mice infected with BA or CE parasites at 6 and 25 weeks post-inoculation. These data indicate that L (V.) braziliensis-infected mice harbor parasites that spread, even when these animals do not display overt lesions. In addition, this is the first report of the presence of the parasite in the bone marrow of mice inoculated with L. (V.) braziliensis.
Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Animais , Medula Óssea , Leishmaniose Cutânea/parasitologia , Camundongos , Pele/patologiaRESUMO
Leishmaniasis is a zoonotic and neglected disease, which represents an important public health problem worldwide. Different species of Leishmania are associated with different manifestations, and a practical problem that can worsen the condition of hosts infected with Leishmania is the secondary infection caused by bacteria. This review aims to examine the importance and prevalence of bacteria co-infection during leishmaniasis and the nature of this ecological relationship. In the cases discussed in this review, the facilitation phenomenon, defined as any interaction where the action of one organism has a beneficial effect on an organism of another species, was considered in the Leishmania-bacteria interaction, as well as the effects on one another and their consequences for the host.
Assuntos
Leishmania , Leishmaniose , Bactérias/genética , Humanos , Leishmaniose/epidemiologiaRESUMO
OBJECTIVES: Leishmaniasis is a zoonotic disease and several drugs have been used in the treatment, including meglumine antimoniate (AME). The chemotherapy reaches clinical cure but does not eliminate parasites, contributing to drug resistance. To improve AME efficacy we incorporated it in anionic liposomes. The antiparasitic activity and intracellular localization were investigated in canine macrophages infected with Leishmania infantum. METHODS: Liposomes (L-AME) is composed of egg phosphatidylcholine, cholesterol, palmitoyl oleoyl phosphatidyl serine and α-tocopherol (4 : 3 : 0.4 : 0.07 mol%) plus AME. L-AME size, polydispersity, zeta potential and morphology were analysed as well as antileishmanial activity and intracellular localization in DH82 macrophages. KEY FINDINGS: Liposomes (360 nm) zeta potential range from -40 to -65 mV, had 23% encapsulation efficiency and were stable for 180 days at 4°C. Free AME was cytotoxic towards L. infantum infected macrophages (ID50 = 0.012 M) while L-AME did not reduce cell viability. L-AME colocalized with parasites inside macrophages in a time-dependent manner, and reduced the percentage of infected cells and the number of intracellular parasites, decreasing the infection index (75-80%) twice as compared with AME treatment. CONCLUSIONS: Liposomal AME is a promising delivery system for treating visceral leishmaniasis, improving meglumine efficacy against L. infantum and minimizing its cytotoxicity towards canine macrophages.
Assuntos
Leishmania infantum , Compostos Organometálicos , Animais , Cães , Lipossomos , Macrófagos , Antimoniato de Meglumina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Compostos Organometálicos/farmacologia , Compostos Organometálicos/uso terapêuticoRESUMO
Telomeres from different eukaryotes, including trypanosomatids, are transcribed into TERRA noncoding RNAs, crucial in regulating chromatin deposition and telomere length. TERRA is transcribed from the C-rich subtelomeric strand towards the 3'-ends of the telomeric array. Using bioinformatics, we confirmed the presence of subtelomeric splice acceptor sites at all L. major chromosome ends. Splice leader sequences positioned 5' upstream of L. major chromosomes subtelomeres were then mapped using SL-RNA-Seq libraries constructed from three independent parasite life stages and helped confirm TERRA expression from several chromosomes ends. Northern blots and RT-qPCR validated the results showing that L. major TERRA is processed by trans-splicing and polyadenylation coupled reactions. The number of transcripts varied with the parasite's life stage and continuous passages, being more abundant in the infective forms. However, no putative subtelomeric promoters involved in TERRA's transcriptional regulation were detected. In contrast, the observed changes in parasite's telomere length during development, suggest that differences in telomeric base J levels may control TERRA transcription in L. major. Also, TERRA-R loops' detection, mainly in the infective forms, was suggestive of TERRA's involvement in telomere protection. Therefore, Leishmania TERRA shares conserved features with other eukaryotes and advances new telomere specific functions in a Public Health-impacting parasite.
Assuntos
Clonagem Molecular/métodos , Perfilação da Expressão Gênica/métodos , Leishmania major/crescimento & desenvolvimento , Fatores de Transcrição/genética , Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Leishmania major/genética , Leishmania major/metabolismo , Poliadenilação , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Splicing de RNA , Análise de Sequência de RNA , Telômero/genética , Fatores de Transcrição/metabolismoRESUMO
Human visceral leishmaniasis (VL) and canine leishmaniasis (CanL) in countries of South and Central America are caused by Leishmania infantum and has been endemic in Brazil for several years. The parasite biodiversity as well as the pharmacologic properties of drugs and the host species, are involved in the efficacy or inefficacy of leishmaniasis treatments. Although there are substantial number of reports describing the genetic characterization of the clinical field isolates of L. infantum,the phenotypic parameters have been less studied. In this study isolates from human and canine leishmaniasis (Hum1 and Can1) obtained in Campinas, São Paulo state, Brazil were identified as L. infantum. The Hum1 and Can1 isolates exhibited typical promastigote growth pattern. Regarding morphological features Can1 isolate differed in cell size. The infectivity in vitro of both isolatesis lower compared to the reference strain of L. infantum. Moreover, the in vivo infectivity of the three parasites is similar in Balb/c mice. The Hum1 isolate is more sensitive to leishmanial drugs (amphotericin B, miltefosine and glucantime) than the Can1 isolate when inside human macrophages, but not when inside canine macrophages. These findings indicated that L. infantum isolates differs in some phenotypic characteristics.
Assuntos
Doenças do Cão/parasitologia , Leishmania infantum/classificação , Leishmaniose Visceral/parasitologia , Animais , Brasil/epidemiologia , Linhagem Celular , Criança , Doenças do Cão/tratamento farmacológico , Doenças do Cão/epidemiologia , Cães , Doenças Endêmicas , Feminino , Humanos , Leishmania infantum/genética , Leishmania infantum/crescimento & desenvolvimento , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/epidemiologia , Macrófagos/citologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Reação em Cadeia da PolimeraseRESUMO
Parasitic diseases affect more than one billion people worldwide, and most of them are chronic conditions in which the treatment and prevention are difficult. The appearance of granulomas, defined as organized and compact structures of macrophages and other immune cells, during various parasitic diseases is frequent, since these structures will only form when individual immune cells do not control the invading agent. Th2-typering various parasitic diseases are frequent, since these structures will only form when individual immune cells do not control the invading agent. The characterization of granulomas in different parasitic diseases, as well as recent findings in this field, is discussed in this review, in order to understand the significance of the granuloma and its modulation in the host-parasite interaction and in the immune, pathological, and parasitological aspects of this interaction. The parasitic granulomatous diseases granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, neurocysticercosis, and schistosomiasis mansoni are discussed as well as the mechanistic and dynamical aspects of the infectious granulomas.
Assuntos
Granuloma/imunologia , Granuloma/patologia , Macrófagos/imunologia , Neurocisticercose/imunologia , Esquistossomose mansoni/imunologia , Toxoplasmose/imunologia , Animais , Granuloma/parasitologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Macrófagos/patologia , Neurocisticercose/patologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/patologia , Taenia solium/imunologia , Toxoplasma/imunologia , Toxoplasmose/patologiaRESUMO
Leishmaniasis is a poverty-related disease, the chemotherapy of which is based on few drugs. The in vitro macrophage-amastigote model using mouse peritoneal cells, human-monocyte transformed macrophages and immortalized cell lines have been used to test new and safe antileishmanial drugs. Considering the differences for drug sensitivities between these Leishmania infected cells, the efficacy of amphotericin B, pentavalent antimonial, miltefosine and resveratrol was evaluated in a recently developed ex vivo culture of macrophages isolated from mouse lesion induced by L. amazonensis (CD11b+F4/80+CD68+CD14+) compared with infected peritoneal macrophages (CD11b+F4/80+CD68+CD14+). The results show that IC50 values of amphotericin B, miltefosine and pentavalent antimonial for parasites in lesional and peritoneal macrophages were similar, although high doses of these compounds did not result in total clearance of parasites in lesional cells (amphotericin B), peritoneal cells (miltefosine) and both cell cultures (pentavalent antimonial). Amastigotes infecting lesional macrophages were more resistant to resveratrol as compared to parasites in peritoneal macrophages. The cytoxicity of miltefosine and resveratrol was higher in infected peritoneal macrophages than in lesional cells. These data suggest that the antileishmanial effect and citotoxicity of some anti leishmanial compounds are dependent of macrophage source and mouse peritoneal macrophages loaded with amastigotes do not represent the lesion cell.
Assuntos
Antiprotozoários/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Macrófagos/parasitologia , Anfotericina B/farmacologia , Animais , Técnicas de Cultura de Células , Feminino , Concentração Inibidora 50 , Leishmaniose/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologiaRESUMO
Hyperbaric oxygen is a clinical treatment that contributes to wound healing by increasing fibroblasts proliferation, collagen synthesis, and production of growth factors, inducing angiogenesis and inhibiting antimicrobial activity. It also has been shown that hyperbaric oxygen treatment (HBO), through the activation of nitric oxide synthase promotes an increase in the nitric oxide levels that may improve endothelial progenitor cells (EPC) mobilization from bone marrow to the peripheral blood and stimulates the vessel healing process. However, cellular mechanisms involved in cell proliferation and activation of EPC after HBO treatment remain unknown. Therefore, the present work aimed to analyze the effect of HBO on the proliferation of pre-treated bone marrow-derived EPC with TNF-alpha. Also, we investigated the expression of ICAM and eNOS by immunochemistry, the production of reactive species of oxygen and performed an in vitro wound healing. Although 1h of HBO treatment did not alter the rate of in vitro wound closure or cell proliferation, it increased eNOS expression and decreased ICAM expression and reactive oxygen species production in cells pre-treated with TNF-alpha. These results indicate that HBO can decrease the inflammatory response in endothelial cells mediated by TNF-alpha, and thus, promote vascular recovery after injury.
Assuntos
Proliferação de Células/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Oxigênio/farmacologia , Animais , Células da Medula Óssea/citologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Graphene oxide (GO) and silver nanoparticles (AgNPs) can be formed into a hybrid nanomaterial, known as GOAg nanocomposite, which presents high antibacterial activity. The successful translation of this nanomaterial into medical use depends on critical information about its toxicological profile. In keeping with a Safe-by-design approach, we evaluated the immunotoxicity of GOAg using J774 and primary murine macrophages. The interaction between GOAg and macrophages was investigated with a scanning electron microscope (SEM). High-throughput technologies were employed to evaluate cell viability, apoptosis/necrosis, mitochondrial depolarization and lipid peroxidation. The inflammogenicity of nanomaterials was predicted after quantification of the cytokines IL-1ß, TNF-α and IL-10 before and after stimulation with interferon-γ (IFN-γ). The ratio between CD80 and CD206 macrophage populations were also estimated. In addition, the production of nitric oxide (NO) was investigated. SEM surveys revealed the potential of GOAg to induce frustrated phagocytosis. GOAg induced a dose-dependent mitochondrial depolarization, apoptosis and lipid peroxidation to J774 macrophages. GOAg toxicity was not modified in an inflammatory microenvironment, but its toxicity was within the range of concentrations used in bacterial inactivation. GOAg did not induce primary macrophages to significantly produce inflammatory cytokines, and previous macrophage stimulation did not enhance GOAg inflammogenicity. Additionally, the pristine nanomaterials and GOAg do not shift macrophages polarization towards M1. Sublethal concentrations of GOAg did not impair macrophages NO production. Finally, we suggest options for improvement of GOAg nanocomposite in ways that may help minimize its possible adverse outcomes to human health.
Assuntos
Anti-Infecciosos/toxicidade , Citocinas/imunologia , Grafite/toxicidade , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Nanocompostos/toxicidade , Prata/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Humanos , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose/efeitos dos fármacos , Propriedades de SuperfícieRESUMO
The cell culture insert system is a culturing system for the study of contact-independent cellular communication. Leishmaniasis is a neglect tropical disease with no vaccines and the available drugs present toxic side effects. Studies on Leishmania interaction with host macrophages aim to develop strategies for parasite control and drug development. The purpose of this study was to evaluate the effects of interaction between non-infected and L. amazonensis-infected human macrophages, by using the cell culture system. The results showed that the infection index was reduced by 56.2% as compared to controls only when infected macrophages were inserted on both sides of the Transwell membranes. An improvement in macrophage viability was also observed in this cell culture. The levels of interleukin-1ß, an inflammatory cytokine, and nitric oxide, a microbicidal molecule, did not increase in L. amazonensis-infected macrophage cultures in the Transwell system; thus other soluble factors were responsible for parasite control
Assuntos
Leishmania mexicana , Leishmaniose , Cultura Primária de Células , MacrófagosRESUMO
Several immune markers have been studied in controlling American tegumentary leishmaniosis based on mouse models. However, there is a lack of studies regarding human tegumentary leishmaniosis caused by Leishmania braziliensis. In this study, hypoxia-inducible factor-1α was found to be an important effector element in the localized control of human cutaneous and mucocutaneous lesions.
Assuntos
Regulação da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Adulto , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genéticaRESUMO
Cerebral malaria (CM) is a multifactorial syndrome involving an exacerbated proinflammatory status, endothelial cell activation, coagulopathy, hypoxia, and accumulation of leukocytes and parasites in the brain microvasculature. Despite significant improvements in malaria control, 15% of mortality is still observed in CM cases, and 25% of survivors develop neurologic sequelae for life-even after appropriate antimalarial therapy. A treatment that ameliorates CM clinical signs, resulting in complete healing, is urgently needed. Previously, we showed a hyperbaric oxygen (HBO)-protective effect against experimental CM. Here, we provide molecular evidence that HBO targets brain endothelial cells by decreasing their activation and inhibits parasite and leukocyte accumulation, thus improving cerebral microcirculatory blood flow. HBO treatment increased the expression of aryl hydrocarbon receptor over hypoxia-inducible factor 1-α (HIF-1α), an oxygen-sensitive cytosolic receptor, along with decreased indoleamine 2,3-dioxygenase 1 expression and kynurenine levels. Moreover, ablation of HIF-1α expression in endothelial cells in mice conferred protection against CM and improved survival. We propose that HBO should be pursued as an adjunctive therapy in CM patients to prolong survival and diminish deleterious proinflammatory reaction. Furthermore, our data support the use of HBO in therapeutic strategies to improve outcomes of non-CM disorders affecting the brain.-Bastos, M. F., Kayano, A. C. A. V., Silva-Filho, J. L., Dos-Santos, J. C. K., Judice, C., Blanco, Y. C., Shryock, N., Sercundes, M. K., Ortolan, L. S., Francelin, C., Leite, J. A., Oliveira, R., Elias, R. M., Câmara, N. O. S., Lopes, S. C. P., Albrecht, L., Farias, A. S., Vicente, C. P., Werneck, C. C., Giorgio, S., Verinaud, L., Epiphanio, S., Marinho, C. R. F., Lalwani, P., Amino, R., Aliberti, J., Costa, F. T. M. Inhibition of hypoxia-associated response and kynurenine production in response to hyperbaric oxygen as mechanisms involved in protection against experimental cerebral malaria.
Assuntos
Encéfalo/metabolismo , Hipóxia/metabolismo , Cinurenina/metabolismo , Malária Cerebral/metabolismo , Oxigênio/metabolismo , Animais , Circulação Cerebrovascular/fisiologia , Células Endoteliais/metabolismo , Feminino , Oxigenoterapia Hiperbárica/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação/fisiologiaRESUMO
Plant products are an important source of bioactive agents against parasitic diseases, including leishmaniasis. Among these products, vegetable oils have gained ground in the pharmaceutical field. Here we report the development of nanoemulsions as a delivery system for copaiba and andiroba oils (nanocopa and nanoandi) in order to test their effects on Leishmania infantum and L. amazonensis. The nanocopa and nanoandi had an average particle size of 76.1 and 88.1, respectively with polydispersity index 0.14 to 0.16 and potential zeta -2.54 to -3.9. The data indicated toxic activity of nanocopa and nanoandi against promastigotes of both Leishmania species ultrastructural analyses by scanning electron microscopy revealed that exposition to nanoemulsions induced oval cell shape and retracted flagella. The treatment with nanocopa and nanoandi led to a reduction in L. infantum and L. amazonensis infection levels in macrophage cultures. The nanoemulsions treatment have significant beneficial effects on all the parameters evaluated in lesions induced by L. amazonensis (lesion size, parasite burden and histopathology) on BALB/c mice. The treatment of L. infantum-infected BALB/c mice with nanoemulsions also showed promising results reducing parasite burden in spleen and liver and improving histopathological features.
Assuntos
Fabaceae/química , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Óleos Voláteis/administração & dosagem , Animais , Antiprotozoários/uso terapêutico , Emulsões , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Intestinos/patologia , Rim/patologia , Leishmania infantum/ultraestrutura , Leishmania mexicana/ultraestrutura , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/patologia , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/patologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Óleos Voláteis/química , Fosforilcolina/análogos & derivados , Fosforilcolina/uso terapêutico , Estômago/patologiaRESUMO
Leishmanioses are neglected diseases and the parasite Leishmania survives and proliferates within mononuclear phagocytes, particularly macrophages. In vitro studies of the immunology and cell biology of leishmaniosis are performed in murine peritoneum and bone marrow macrophages and immortalized cell lines despite the normal and injured tissue-specific heterogeneity of macrophages. In this work, we established an ex vivo methodology to culture lesional cells from BALB/c mice infected with Leishmania amazonensis. The cells were successfully isolated from footpad skin lesions and those exhibiting macrophage morphology were maintained in long-term culture (12 days), while the small number of lymphocytes, polymorphonuclear and unidentified cells died after 1 day of culture. The frequency of infected cells decreased over 2 days. Most lesional cells cultivated ex vivo were myeloid CD11b+ CD14+ F4/80+ CD68+ cells. Low levels of IFN-γ and IL-4, IL-10 production and low arginase and phagocytic activities were detected in ex vivo lesional cell cultures. The ex vivo model developed in this study open perspectives for studying the biology of leishmanial lesions in cellular subpopulations and at the single-cell level.
Assuntos
Antígenos de Superfície/imunologia , Leishmania/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos Peritoneais/imunologia , Pele/citologia , Animais , Arginase/biossíntese , Técnicas de Cultura de Células , Células Cultivadas , Modelos Animais de Doenças , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-4/biossíntese , Leishmaniose Cutânea/microbiologia , Linfócitos/microbiologia , Macrófagos Peritoneais/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/microbiologia , Fagocitose/imunologia , Pele/patologiaRESUMO
Conventional chemotherapy for leishmaniasis includes considerably toxic drugs and reports of drug-resistance are not uncommon. Liposomal encapsulated drugs appear as an option for the treatment of leishmaniasis, providing greater efficacy for the active and reducing its side effects by promoting superior tissue absorption, favouring drug penetration into the macrophages, and retarding its clearance from the site of action. In this paper, a review on the advances achieved with liposome-based anti-leishmaniasis drug delivery systems is presented. Formulations prepared with either conventional or modified (sugar-coated, cationic, niosomes, peptides- and antibodies-bounded) liposomes for the delivery of pentavalent antimonials, amphotericin B, pentamidine, paromomycyn, and miltefosine were covered. This literature review depicts a scenario of no effective therapeutic agents for the treatment of this neglected disease, where liposomal formulations appear to improve the effectiveness of the available antileishmania agents.
Assuntos
Antiprotozoários/química , Antiprotozoários/uso terapêutico , Leishmaniose/tratamento farmacológico , Lipossomos/química , Anfotericina B/química , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Animais , Antiprotozoários/farmacologia , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Nanopartículas , Paromomicina/química , Paromomicina/farmacologia , Paromomicina/uso terapêutico , Tamanho da Partícula , Pentamidina/química , Pentamidina/farmacologia , Pentamidina/uso terapêutico , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Propriedades de SuperfícieRESUMO
Particular lipid profiles have been found in two different protozoa of the Leishmania genus. Leishmania infantum, a visceral leishmaniasis causative agent and Leishmania amazonensis, a cutaneous leishmaniasis, reveal distinctive lipid contents of phosphatidylethanolamine and phosphatidylserine plasmalogens, sphingolipids, phosphatidylinositols, phosphatidylcholine, and phosphatidylethanolamine, which have been shown to be related to species, life-cycle of the parasite, and macrophage infection. L. infantum displayed a higher content of phosphatidylethanolamine plasmalogens than L. amazonensis, which may help to differentiate their unique clinical manifestations. Phosphatidylserines plasmalogens are also found to be an important lipid class for the intracellular form of the parasite. Our findings also reveal lipid classes that may be involved in visceralization pathways and parasite differentiation.