Schinus terebenthifolius Raddi extracts: From sunscreen activity toward protection of the placenta to Zika virus infection, new uses for a well-known medicinal plant.

Schinus terebinthifolius Raddi is a well-known medicinal plant native of South America. This species has demonstrated important biological activities such as antihypertensive and vasodilator, antimicrobial, anti-inflammatory and antioxidant. However, no studies have been, so far, reported with the fruits of S. terebinthifolius as a protector of the placenta against Zika virus infection and as sunscreen agents. The present study aimed to investigate new uses for the ethanolic fruit extracts of S. terebinthifolius, from fruits'peel (STPE) and from the whole fruits (STWFE). Zika virus (ZIKV) has been linked to several fetal malformations, such as microcephaly and other central nervous system abnormalities. Thus, the potential of these natural extracts against ZIKV infection was evaluated, using an in vitro method. The photoprotective potential, determined by spectrometry, along with phenolic content, antioxidant capacity, and chemical composition of both extracts were also evaluated. The chemical composition of the extracts was evaluated by HPLC-UV / vis. The cytotoxicity of peel and whole fruit extracts in vero E6 cell lines, in placental cell lines and placental explant cultures were evaluated by the MTT assay. The infectivity of placental cells and explants was evaluated by qRT-PCR and the effects of extracts on ZIKV infection were investigated using HTR-8/SVneo cells, pre-treated with 100 µg mL-1 of STWFE for 1 h, and infected with MR766 (AD) or PE243 (EH) ZIKV strains. STFE and STWFE were well-tolerated by both placental-derived trophoblast cell line HTR-8/SVneo as well as by term placental chorionic villi explants, which indicate absence of cytotoxicity in all analysed concentrations. Two strains of ZIKV were tested to access if pre-treatment of trophoblast cells with the STWFE would protect them against infection. Flow cytometry analysis revealed that STWFE extract greatly reduced ZIKV infection. The extracts were also photoprotective with SPF values equivalent to the standard, benzophenone-3. The formulations prepared in different concentrations of the extracts (5-10 %) had shown maximum SPF values of 32.21. STWFE represents a potential natural mixture to be used in pregnancy in order to restrain placental infection by ZIKV and might potentially protect fetus against ZIKV-related malformations. The extracts exhibited photoprotective activity and some of the phenolic compounds, mainly resveratrol, catechin and epicatechin, are active ingredients in all assayed activities. The development of biotechnological/medical products, giving extra value to products from family farming, is expected, with strong prospects for success.

Cytokines and chemokines triggered by Chikungunya virus infection in human patients during the very early acute phase.

BACKGROUND: The immune response against the Chikungunya virus (CHIKV) during the very early acute phase is not fully elucidated. Therefore we explored the cytokine and chemokine profile triggered by CHIKV in infected patients. METHODS: Cytokines, chemokines and C5a anaphylatoxin were analysed in serum from CHIKV-infected patients during the viraemic phase (mean 2.97±1.27 d after illness onset) compared with a healthy group. RESULTS: CHIKV-infected patients had a significant increase of interferon-α (IFN-α), interleukin-6 (IL-6), interleukin-8 (CXCL8/IL-8), interleukin-10 (IL-10), interferon-γ (IFN-γ), monokine induced by interferon-γ (CXCL9/MIG), monocyte chemoattractant protein-1 (CCL2/MCP-1), interferon-γ-induced protein-10 (CXCL10/IP-10) and complement C5a anaphylatoxin. CONCLUSIONS: The very early acute immune response triggered against CHIKV leads to an increase in pro-inflammatory immune mediators such as IFN-γ and its induced chemokines, and a high level of C5a anaphylatoxin as a result of complement activation.

Cellular and Molecular Immune Response to Chikungunya Virus Infection.

Chikungunya virus (CHIKV) is a re-emergent arthropod-borne virus (arbovirus) that causes a disease characterized primarily by fever, rash and severe persistent polyarthralgia. In the last decade, CHIKV has become a serious public health problem causing several outbreaks around the world. Despite the fact that CHIKV has been around since 1952, our knowledge about immunopathology, innate and adaptive immune response involved in this infectious disease is incomplete. In this review, we provide an updated summary of the current knowledge about immune response to CHIKV and about soluble immunological markers associated with the morbidity, prognosis and chronicity of this arbovirus disease. In addition, we discuss the progress in the research of new vaccines for preventing CHIKV infection and the use of monoclonal antibodies as a promising therapeutic strategy.