During bloodfeeding, the presence of sand fly saliva in the hemorrhagic pool where Leishmania is also inoculated modulates the development of host immune mechanisms creating a favorable environment for disease progression. To date, information obtained through experimental models suggests that sand fly saliva induces cellular recruitment and modulates production of eicosanoids. However, the effect of sand fly saliva in the different steps of the inflammatory response triggered by Leishmania remains undefined. Here we further investigate if interaction of Lutzomyia longipalpis salivary gland sonicate (SGS) with different host cells present during the initial inflammatory events regulate Leishmania infantum infectivity. Initially, we observed that incubation of human peripheral blood mononuclear cells (PBMC) with Lu. longipalpis SGS in the presence of L. infantum significantly increased IL-10 but did not alter expression of IFN-γ and TNF-α by CD4+ T cells induced by the parasite alone. Interestingly, incubation of PBMC with Lu. longipalpis SGS alone or in the presence of L. infantum resulted in increased IL-17 production. The presence of IL-17 is related to neutrophil recruitment and plays an important role at the site of infection. Here, we also observed increased migration of neutrophil using an in vitro chemotactic assay following incubation with supernatants from PBMC stimulated with L. infantum and Lu. longipalpis SGS. Neutrophil migration was abrogated following neutralization of IL-17 with specific antibodies. Moreover, culture of human neutrophils with L. infantum in the presence of Lu. longipalpis SGS promoted neutrophil apoptosis resulting in increased parasite viability. Neutrophils operate as the first line of defense in the early stages of infection and later interact with different cells, such as macrophages. The crosstalk between neutrophils and macrophages is critical to determine the type of specific immune response that will develop. Here, we observed that co-culture of human macrophages with autologous neutrophils previously infected in the presence of Lu. longipalpis SGS resulted in a higher infection rate, accompanied by increased production of TGF-β and PGE2. Our results provide new insight into the contribution of Lu. longipalpis SGS to L. infantum-induced regulation of important inflammatory events, creating a favorable environment for parasite survival inside different host cells.

Abstract:The plant Hydrocotyle umbellata L., Araliaceae (water pennywort), is widely used in Brazilian folk medicine to reduce anxiety. This work investigates the anxiolytic-like effects of the ethanol extract from H. umbellata subterraneous parts as well as the extract's other putative central nervous system effects that could justify its common use. Oral dosing of the extract (0.3 and 1 g/kg) clearly showed an anxiolytic-like profile in the elevated plus maze test where it increased the percentage of entries into and the time spent in the open arms of the maze. In the marble-burying test, the extract induced anxiolyticlike effects only at a dose of 1 g/kg, which also causes mild sedative properties in other models. The sedated state was characterized by a slight reduction in spontaneous exploratory activity during the open field test and a potentiating of pentobarbital-induced hypnosis. No signs of motor impairment were detected in the rota rod or chimney tests. The extract did not show antidepressant properties in mice as assessed by the forced swimming test. These results support the use of H. umbellata in Brazilian folk medicine as an anxiolytic and contribute to the scientific knowledge of this possible phytotherapeutic resource.

BACKGROUND Herpesvirus transmission between humans and non-human primate (NHP) can occur through contact scratches with lesions, infected saliva, and mainly through contaminated food. Therefore, cross-infection can lead to severe illness or even death for both the animal and human. In 2017, during the yellow fever (YF) outbreak in Brazil, species of the New World Primates (NWP) from Rio de Janeiro state, tested negative for yellow fever virus (YFV) detection. OBJECTIVES To evaluate herpesvirus in the population NWP in Rio de Janeiro. METHODS To investigate, liver samples of 283 NWP, from several regions of the state of Rio de Janeiro, were tested for the herpesvirus family using a Pan -polymerase chain reaction ( Pan -PCR) and sequencing. FINDINGS 34.6% (98/283) tested positive for at least one herpesvirus; 29.3% (83/283) tested positive to Human alphaherpesvirus 1 (HSV-1), this virus from humans can be lethal to New World monkey; 13% (37/283) were detected Callitrichine gammaherpesvirus 3 (CalHV-3), responsible for lymphoproliferative disease that can be fatal in NWP. In addition, CalHV-3 / HSV-1 co-infection was in 11.6% (33/283) of the samples. MAIN CONCLUSIONS Pan -herpesvirus was useful to identify species-specific herpesviruses and virus from human that can infect animals. Furthermore, during an outbreak of YF other infections should be monitored.