HIRO GOTO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Medicina Preventiva, Faculdade de Medicina - Docente
LIM/38 - Laboratório de Epidemiologia e Imunobiologia, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/38 - Laboratório de Epidemiologia e Imunobiologia, Hospital das Clínicas, Faculdade de Medicina - Líder
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- ATP6V(0)d2 controls Leishmania parasitophorous vacuole biogenesis via cholesterol homeostasis(2019) PESSOA, Carina Carraro; REIS, Luiza Campos; RAMOS-SANCHEZ, Eduardo Milton; ORIKAZA, Cristina Mary; CORTEZ, Cristian; LEVATTI, Erica Valadares de Castro; BADARO, Ana Carolina Benites; YAMAMOTO, Joyce Umbelino da Silva; D'ALMEIDA, Vania; GOTO, Hiro; MORTARA, Renato Arruda; REAL, FernandoV-ATPases are part of the membrane components of pathogen-containing vacuoles, although their function in intracellular infection remains elusive. In addition to organelle acidification, V-ATPases are alternatively implicated in membrane fusion and anti-inflammatory functions controlled by ATP6V(0)d2, the d subunit variant of the V-ATPase complex. Therefore, we evaluated the role of ATP6V(0)d2 in the biogenesis of pathogen-containing vacuoles using ATP6V(0)d2 knock-down macrophages infected with the protozoan parasite Leishmania amazonensis. These parasites survive within IFN gamma/LPS-activated inflammatory macrophages, multiplying in large/fusogenic parasitophorous vacuoles (PVs) and inducing ATP6V(0)d2 upregulation. ATP6V(0)d2 knock-down decreased macrophage cholesterol levels and inhibited PV enlargement without interfering with parasite multiplication. However, parasites required ATP6V(0)d2 to resist the influx of oxidized low-density lipoprotein (ox-LDL)-derived cholesterol, which restored PV enlargement in ATP6V(0)d2 knock-down macrophages by replenishing macrophage cholesterol pools. Thus, we reveal parasite-mediated subversion of host V-ATPase function toward cholesterol retention, which is required for establishing an inflammation-resistant intracellular parasite niche. Author summary V-ATPases control acidification and other processes at intracellular vesicles that bacteria and parasites exploit as compartments for replication and immune evasion. We report that the protozoan intracellular parasite Leishmania amazonensis resists inflammatory macrophage immune responses and upregulates an alternative isoform of subunit d of V-ATPase (ATP6V(0)d2). Leishmania are still sequestered within acidified parasitophorous vacuoles (PVs) in cells lacking ATP6V(0)d2, but these PVs do not enlarge in volume, a distinguishing feature of intracellular infection by these parasites. Cholesterol levels in ATP6V(0)d2-deficient cells are reduced and exogenous cholesterol repletion can restore vacuole size, leading to enhanced parasite killing. This study demonstrates the ATP6V(0)d2-mediated interplay of macrophage cholesterol retention and control of the biogenesis of large pathogen-containing vacuoles. The study provides grounds for the development of new therapeutic strategies for diseases caused by intracellular pathogens sheltered in host cell compartments.
- Macrophages From Subjects With Isolated GH/IGF-I Deficiency Due to a GHRH Receptor Gene Mutation Are Less Prone to Infection by Leishmania amazonensis(2019) BARRIOS, Monica R.; CAMPOS, Viviane C.; PERES, Nalu T. A.; OLIVEIRA, Lais L. de; CAZZANIGA, Rodrigo A.; SANTOS, Marcio B.; AIRES, Murilo B.; SILVA, Ricardo L. L.; BARRETO, Aline; GOTO, Hiro; ALMEIDA, Roque P.; SALVATORI, Roberto; AGUIAR-OLIVEIRA, Manuel H.; JESUS, Amelia M. R.Isolated growth hormone (GH) deficiency (IGHD) affects approximately 1 in 4,000 to 1 in 10,000 individuals worldwide. We have previously described a large cohort of subjects with IGHD due to a homozygous mutation in the GH releasing hormone (GHRH) receptor gene. These subjects exhibit throughout the life very low levels of GH and its principal mediator, the Insulin Growth Factor-I (IGF-I). The facilitating role of IGF-I in the infection of mouse macrophages by different Leishmania strains is well-known. Nevertheless, the role of IGF-I in Leishmania infection of human macrophages has not been studied. This study aimed to evaluate the behavior of Leishmania infection in vitro in macrophages from untreated IGHD subjects. To this end, blood samples were collected from 14 IGHD individuals and 14 age and sex-matched healthy controls. Monocytes were isolated and derived into macrophages and infected with a strain of Leishmania amazonensis. In addition, IGF-I was added to culture medium to evaluate its effect on the infection. Cytokines were measured in the culture supernatants. We found that macrophages from IGHD subjects were less prone to Leishmania infection compared to GH sufficient controls. Both inflammatory and anti-inflammatory cytokines increase only in the supernatants of the control macrophages. Addition of IGF-I to the culture medium increased infection rates. In conclusion, we demonstrated that IGF-I is crucial for Leishmania infection of human macrophages.
conferenceObject Altered expression of microRNAs in infections with cutaneous and visceral strains of Leishmania(2019) GOTO, H.; SOUZA, M. A.; RAMOS-SANCHEZ, E. M.; MUXEL, S. M.; BRITO, M. E. F.; PEREIRA, V. R. A.; FLOETER-WINTER, L. M.- Association between Insulin-Like Growth Factor-I Levels and the Disease Progression and Anemia in Visceral Leishmaniasis(2019) PINHO, Flaviane Alves de; VENDRAME, Celia Maria Vieira; MACIEL, Bruna Leal Lima; SILVA, Lucilene dos Santos; MIYASHIRO, Samantha Ive; JERONIMO, Selma Maria Bezerra; GOTO, HiroWe analyzed the association between insulin-like growth factor-I (IGF-I) and the pathogenesis of anemia during active visceral leishmaniasis (VL). Serum levels of IGF-I, IGF-binding protein 3 (IGFBP3), and cytokines were measured in samples from individuals with active VL and cured VL, asymptomatic Leishmania-infected, and noninfected individuals. Then, we extended our analysis to VL dogs to evaluate hematimetric parameters, bone marrow alterations, and cytokine and IGF-I expression. We identified a positive correlation between lower IGF-I and IGFBP3 levels in active VL patients and lower hemoglobin levels. In infected dogs, there was a positive correlation between lower IGF-I expression in the bone marrow and lower peripheral blood hematocrit and hemoglobin levels. There was no correlation between decreased IGF-I level/expression and any measured cytokine serum levels in either host. The data suggest that low IGF-I expression is associated with pathogenesis of anemia in active VL, primarily in severe cases, by mechanisms other than alterations in cytokine production.