Antiviral and Virucidal Activities of Uncaria tomentosa (Cat's Claw) against the Chikungunya Virus.

Uncaria tomentosa (UT) is a medicinal plant popularly known as cat's claw belonging to the Rubiaceae family that has been reported to display antiviral and anti-inflammatory activities. The chikungunya virus (CHIKV) outbreaks constitute a Brazilian public health concern. CHIKV infection develops an abrupt onset of fever, usually accompanied by a skin rash, besides incapacitating polyarthralgia. There is no vaccine available or treatment for CHIKV infection. The present study evaluates the hydroalcoholic extract of UT bark as a potential antiviral against CHIKV. The in vitro antiviral activity of the UT extract against the Brazilian CHIKV strain was assessed using quantitative reverse transcription polymerase chain reaction, flow cytometry, and plaque assay. Results obtained demonstrated that UT inhibits CHIKV infection in a dose-dependent manner. At the non-cytotoxic concentration of 100 µg/mL, UT exhibited antiviral activity above 90% as determined by plaque reduction assay, and it reduced the viral cytopathic effect. Similarly, a significant virucidal effect of 100 µg/mL UT was observed after 24 and 48 h post-infection. This is the first report on the antiviral activity of UT against CHIKV infection, and the data presented here suggests UT as a potential antiviral to treat CHIKV infection.

In vitro leishmanicidal activity of monoterpenes present in two species of Protium (Burseraceae) on Leishmania amazonensis.

ETHNOPHARMACOLOGICAL RELEVANCE: Leishmaniasis is a neglected disease that affects millions of people around the world. Parasite resistance and the toxicity to the current treatments lead to the search for new effective molecules. Plants are widely used in traditional and indigenous medicine to treat different diseases. The oleoresin of the genus Protium, which is rich in volatile compounds active against different microorganisms, is among these plants. AIM: The aim of this study was to evaluate the leishmanicidal potential of Protium altsonii (PaEO) and P. hebetatum (PhEO) (Burseraceae) oleoresins, as well as of three representative monoterpenes in their constitution: α-pinene, p-cymene and 1,8-cineole. MATERIALS AND METHODS: Protium altsonii (PaEO) and P. hebetatum (PhEO) oleoresins and three of their constituents were tested in vitro on promastigotes and amastigotes-infected macrophages in different concentrations. Their toxicity for macrophages was analyzed by XTT assay and phagocytic ability. It was evaluated the ability of the compounds to induce NO production on treated-macrophages using Griess reaction and the effect of them in lipid profile on treated-parasite through Thin Layer Chromatography. RESULTS: Our data showed that both essential oils have toxic effect on promastigotes and amastigotes of L. amazonensis in vitro in a dose-dependent manner. PaEO IC50 were 14.8 µg/mL and 7.8 µg/mL and PhEO IC50s were 0.46 µg/mL and 30.5 µg/m for promastigotes and amastigotes, respectively. Toxicity to macrophages was not observed at 50 µg/mL with both EOs. The compounds 1,8- cineole, α-pinene, and p-cymene inhibited amastigotes survival in a dose-dependent manner with IC50s of 48.4 µg/mL, 37 µg/mL, 46 µg/mL, respectively. Macrophage viability was around 90% even at 200 µg/mL and the phagocytic capacity was not altered in the treated-macrophages to up 50 µg/mL. The compounds were not able to modulate the nitric oxide production either at rest or LPS-activated macrophages. In addition, treated promastigote revealed an important change in their lipid profile after 48 h at 50 µg/mL in the presence of the compounds. CONCLUSIONS: The results indicate that oleoresins of Protium genus are potent against Leishmania and α-pinene, p-cymene and 1,8-cineole have anti-Leishmania properties that could be explored in synergistic assays in order to develop new drug candidates.

Reactivation of latent HIV-1 in vitro using an ethanolic extract from Euphorbia umbellata (Euphorbiaceae) latex.

Euphorbia umbellata (E. umbellata) belongs to Euphorbiaceae family, popularly known as Janauba, and its latex contains a combination of phorbol esters with biological activities described to different cellular protein kinase C (PKC) isoforms. Here, we identified deoxi-phorbol esters present in E. umbellata latex alcoholic extract that are able to increase HIV transcription and reactivate virus from latency models. This activity is probably mediated by NF-kB activation followed by nuclear translocation and binding to the HIV LTR promoter. In addition, E. umbellata latex extract induced the production of pro inflammatory cytokines in vitro in human PBMC cultures. This latex extract also activates latent virus in human PBMCs isolated from HIV positive patients as well as latent SIV in non-human primate primary CD4+ T lymphocytes. Together, these results indicate that the phorbol esters present in E. umbellata latex are promising candidate compounds for future clinical trials for shock and kill therapies to promote HIV cure and eradication.

The in vitro antileishmanial activity of essential oil from Aloysia gratissima and guaiol, its major sesquiterpene against Leishmania amazonensis.

Leishmaniases is a tropical disease caused by protozoa of the genus Leishmania for which the current treatment is expensive, besides increasing reports of parasite resistance. This study investigated the anti-Leishmania amazonensis activity of the essential oil from Aloysia gratissima (AgEO) and guaiol, the major sesquiterpene constituent in the oil. Our results showed that AgEO killed promastigotes and intracellular amastigotes at an IC50 of 25 and 0·16 µg mL-1, respectively, while guaiol killed amastigotes at an IC50 of 0·01 µg mL-1. Both AgEO and guaiol were safe for macrophages up to 100 µg mL-1, as evaluated by the dehydrogenase activity, membrane integrity and phagocytic capacity. AgEO and guaiol did not induce nitrite oxide (NO) in resting macrophages and inhibited the production of NO in lipopolysaccharide-stimulated macrophages. The ultrastructural analysis suggested that AgEO and guaiol act directly on parasites, affecting promastigotes kinetoplast, mitochondrial matrix and plasma membrane. Together, these results pointed out that AgEO and guaiol could be promising candidates to develop anti-Leishmania drugs.

Decrease in Dengue virus-2 infection and reduction of cytokine/chemokine production by Uncaria guianensis in human hepatocyte cell line Huh-7.

BACKGROUND: Dengue fever may present hemorrhages and cavitary effusions as result of exacerbated immune responses. We investigated hydro-alcoholic extracts from leaves (UGL) and bark (UGB) of the medicinal species Uncaria guinanensis with respect to antiviral effects in Dengue virus (DENV) infection and in immunological parameters associated with in vivo physiopathological features. METHODS: Chemical profiles from UGB or UGL were compared in thin layer chromatography and 1H nuclear magnetic resonance using flavonoid compounds and a pentacyclic oxindole alkaloid-enriched fraction as references. DENV-2-infected hepatocytes (Huh-7) were treated with extracts. Cell viability, DENV antigens and immunological factors were detected by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. FINDINGS: The UGL mainly differed from UGB by selectively containing the flavonoid kaempferitrin. UGB and UGL improved hepatocyte viability. Both extracts reduced intracellular viral antigen and inhibited the secretion of viral non-structural protein (NS1), which is indicative of viral replication. Reduction in secretion of macrophage migration inhibitory factor was achieved by UGB, of interleukin-6 by UGL, and of interleukin-8 by both UGB and UGL. MAIN. CONCLUSIONS: The U. guianensis extracts presented, antiviral and immunomodulatory effects for DENV and possibly a hepatocyte-protective activity. Further studies may be performed to consider these products as potential candidates for the development of an herbal product for the future treatment of dengue.

Decrease in Dengue virus-2 infection and reduction of cytokine/chemokine production by Uncaria guianensis in human hepatocyte cell line Huh-7

ABSTRACT BACKGROUND Dengue fever may present hemorrhages and cavitary effusions as result of exacerbated immune responses. We investigated hydro-alcoholic extracts from leaves (UGL) and bark (UGB) of the medicinal species Uncaria guinanensis with respect to antiviral effects in Dengue virus (DENV) infection and in immunological parameters associated with in vivo physiopathological features. METHODS Chemical profiles from UGB or UGL were compared in thin layer chromatography and 1H nuclear magnetic resonance using flavonoid compounds and a pentacyclic oxindole alkaloid-enriched fraction as references. DENV-2-infected hepatocytes (Huh-7) were treated with extracts. Cell viability, DENV antigens and immunological factors were detected by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. FINDINGS The UGL mainly differed from UGB by selectively containing the flavonoid kaempferitrin. UGB and UGL improved hepatocyte viability. Both extracts reduced intracellular viral antigen and inhibited the secretion of viral non-structural protein (NS1), which is indicative of viral replication. Reduction in secretion of macrophage migration inhibitory factor was achieved by UGB, of interleukin-6 by UGL, and of interleukin-8 by both UGB and UGL. MAIN CONCLUSIONS The U. guianensis extracts presented, antiviral and immunomodulatory effects for DENV and possibly a hepatocyte-protective activity. Further studies may be performed to consider these products as potential candidates for the development of an herbal product for the future treatment of dengue.

Vernonia polyanthes (Spreng. ) Less.: uma visão geral da sua utilização como planta medicinal, composição química e atividades farmacológicas / Vernonia polyanthes (Spreng. ) Less.: an overview of its use as medicinal plant, chemical composition and pharmacological activities

As aplicações da biodiversidade brasileira em saúde são abrangentes, mas ainda não têm sido bem exploradas oficialmente, considerando o pequeno número de espécies vegetais listadas em compêndios oficiais para uso medicinal. Das espécies conhecidas como assa-peixe, empregadas comumente pela população há muitos anos para diversos fins, sobretudo nas afecções respiratórias, Vernonia polyanthes (Spreng.) Less. é a única regulamentada para utilização no Brasil, indicada como expectorante no Formulário de Fitoterápicos da Farmacopeia Brasileira. Seu cultivo é também praticado em Arranjos Produtivos Locais (APLs) de plantas medicinais, os quais possuem importante papel na conservação e sustentabilidade dos recursos naturais e na economia das famílias que dependem dessa parceria. Esta difusão de uso é característica de diversas espécies que compõem a Relação Nacional de Plantas Medicinais de Interesse ao SUS, mas ainda sem monografias que respaldem os critérios de qualidade para seu uso seguro, conforme o preconizado pela Organização Mundial de Saúde para plantas medicinais. O objetivo deste trabalho foi apresentar uma visão geral do conhecimento científico desta espécie, com foco em sua utilização na fitoterapia, identificação química e atividades farmacológicas, na expectativa de subsidiar a elaboração de monografias de Vernonia polyanthes, agregando valor e qualidade nas atividades dos APLs a longo prazo.(AU)

The applications of the Brazilian biodiversity in health are comprehensive, but still officially underused, since the number of medicinal plants listed in official compendia is minimal. Of several species popularly known as assa-peixe, which have been in common use by the population for many years with diverse pharmacological actions, particularly that related to respiratory affections, Vernonia polyanthes (Spreng.) Less. is the only one listed for use by Herbal Formulary of the Brazilian Pharmacopoeia, indicated as expectorant. It is also cultivated by Local Productive Arrangements (LPA) of medicinal plants, which have an important role in the conservation and sustainability of natural resources, as well as for the economic status of families that depend on this partnership. Several species widely used in folk medicine that compose the National List of Medicinal Plants of Interest to Unified Health System have no monograph that support the quality criteria for the safe use of medicinal plants, following the recommendations of World Health Organization. The present study aims at providing an overview of the scientific knowledge about this species, focusing on its use in herbal medicine, phytochemical identification, and pharmacological activities. This overview can help the elaboration of monographs of Vernonia polyanthes, adding value and quality in the LPA activities at long term.(AU)

Uncaria tomentosa alkaloidal fraction reduces paracellular permeability, IL-8 and NS1 production on human microvascular endothelial cells infected with dengue virus.

Dengue is the major Arbovirus in the world, annually causing morbidity and death. Severe dengue is associated with changes in the endothelial barrier function due to the production of inflammatory mediators by immune cells and by the endothelium. Dengue virus (DENV) replicates efficiently in human endothelial cells in vitro and elicits immune responses resulting in endothelial permeability. Uncaria tomentosa (Willd.) DC.(Rubiaceae), known as cat's claw, has been used in folk medicine for the treatment of a wide-array of symptoms, and several scientific studies reported its antiviral, immunomodulatory, anti-inflammatory and antioxidant properties. Here we infected a human lineage of dermal microvascular endothelial cells (HMEC-1) with DENV-2 and treated it with an alkaloidal fraction from U. tomentosa bark (AFUT). We showed antiviral and immunomodulatory activities of U. tomentosa by determining the NS1 antigen and IL-8 in supernatant of DENV-2 infected HMEC-1. Furthermore, by measurement of transendothelial electrical resistance (TEER) we demonstrated, for the first time, that a plant derivative contributed to the reduction of paracellular permeability in DENV-2 infected HMEC-1. We also showed that IL-8 contributed significantly to the induction of permeability. Although further investigations should be conducted before a new drug can be suggested, our in vitro data support evidence that AFUT could be potentially useful in developing a treatment for severe dengue.

Prevention of experimental diabetes by Uncaria tomentosa extract: Th2 polarization, regulatory T cell preservation or both?

ETHNOPHARMACOLOGICAL RELEVANCE: Uncaria tomentosa (Willd.) DC (Rubiaceae) is a species native to the Amazon rainforest and surrounding tropical areas that is endowed with immunomodulatory properties and widely used around the world. In this study we investigated the immunomodulatory potential of Uncaria tomentosa (UT) aqueous-ethanol extract on the progression of immune-mediated diabetes. MATERIALS AND METHODS: C57BL/6 male mice were injected with MLDS (40 mg/kg) and orally treated with UT at 10-400mg/kg during 21 days. Control groups received MLDS alone or the respective dilution vehicle. Pancreatic mononuclear infiltrate and ß-cell insulin content were analyzed by HE and immunohistochemical staining, respectively, and measured by digital morphometry. Lymphocyte immunophenotyping and cytokine production were determined by flow cytometry analysis. RESULTS: Treating the animals with 50-400mg/kg of UT caused a significant reduction in the glycemic levels, as well as in the incidence of diabetes. The morphometric analysis of insulitis revealed a clear protective effect. Animals treated with UT at 400mg/kg presented a higher number of intact islets and a significant inhibition of destructive insulitis. Furthermore, a significant protection against the loss of insulin-secreting presented ß-cells was achieved, as observed by a careful immunohistochemical evaluation. The phenotypic analysis indicated that the groups treated with higher doses (100-400mg/kg) presented CD4(+) and CD8(+) T-cell values similar to those observed in healthy animals. These same higher doses also increased the number of CD4(+)CD25(+)Foxp3(+) regulatory T-cells. Moreover, the extract modulated the production of Th1 and Th2, with increased levels of IL-4 and IL-5. CONCLUSIONS: The extract was effective to prevent the progression of immune-mediated diabetes by distinct pathways.

Uncaria tomentosa aqueous-ethanol extract triggers an immunomodulation toward a Th2 cytokine profile.

Uncaria tomentosa (Willd.) DC (Rubiaceae) is a large woody vine that is native to the Amazon and Central American rainforests and is used widely in traditional medicine for its immunomodulatory and antiinflammatory activities. The present work used in vivo immunotoxic and in vitro immunomodulatory experiments to investigate the effects of a pentacyclic oxindole alkaloid extract from U. tomentosa bark on lymphocyte phenotype, Th1/Th2 cytokine production, cellular proliferation and cytotoxicity. For the in vivo immunotoxicity testing, BALB/c male mice were treated once a day with 125, 500 or 1250 mg/kg of U. tomentosa extract for 28 days. For the in vitro protocol, lymphocytes were cultured with 10-500 µg/mg of the extract for 48 h. The extract increased the cellularity of splenic white pulp and the thymic medulla and increased the number of T helper lymphocytes and B lymphocytes. Also, a large stimulatory effect on lymphocyte viability was observed. However, mitogen-induced T lymphocyte proliferation was significantly inhibited at higher concentrations of U. tomentosa extract. Furthermore, an immunological polarization toward a Th2 cytokine profile was observed. These results suggest that the U. tomentosa aqueous-ethanol extract was not immunotoxic to mice and was able to modulate distinct patterns of the immune system in a dose-dependent manner.

Development of an HPLC method for the determination of tetranortriterpenoids in Carapa guianensis seed oil by experimental design.

Carapa guianensis crabwood, popularly known in Brazil as "andiroba", is a tree that grows in South and Central America and is used by the local population mainly for its anti-inflammatory and insect anti-feeding activities. Scientific studies on this plant have led to the development of an insect-repellent candle and the investigations of the anti-inflammatory properties of its more important biomarkers-tetranortriterpenoids. These compounds, together with glycerides and fatty acids, are present in the seed oil, the most important commercial product from this plant. The growing scientific and commercial interest in "andiroba oil" has urged the development of adequate analytical methods for assessing its quality. Central composite experimental design is a useful statistical method for the development and optimization of HPLC methods, and has been used for a variety of samples. The aim of this work is to develop a HPLC method for the determination of tetranortriterpenoids in "andiroba" oil, by means of central composite experimental design, as well as to prevalidate this method.

O óleo de chaulmoogra como conhecimento científico: a construção de uma terapêutica antileprótica / Chaulmoogra oil as scientific knowledge: the construction of a treatment for leprosy

Analisa os processos de assimilação e transformação de saberes e práticas terapêuticas que envolvem o uso de plantas medicinais, e destaca o uso, no combate à lepra, do óleo da chaulmoogra. Atenta para os diferentes modos de incorporação e transformação das chaulmoogras em conhecimentos validados cientificamente, tendo em vista a entrada em cena da 'chaulmoogra brasileira'. Privilegia a chegada dos derivados dessa planta à pauta de produção do Instituto Oswaldo Cruz (IOC), na década de 1920, estabelecendo nexos entre os diferentes processos produtivos e articulando-os ao contexto científico no período estudado. O óleo de chaulmoogra representou, até a década de 1940, a grande esperança para a tentativa de cura da lepra. Observa ainda que a terapêutica chaulmúgrica durante esse período, consolidou-se como um saber científico graças à realização de diversas pesquisas feitas em laboratórios de todo o mundo ocidental.(AU)

O óleo de chaulmoogra como conhecimento científico: a construção de uma terapêutica antileprótica / Chaulmoogra oil as scientific knowledge: the construction of a treatment for leprosy

Analisa os processos de assimilação e transformação de saberes e práticas terapêuticas que envolvem o uso de plantas medicinais, e destaca o uso, no combate à lepra, do óleo da chaulmoogra. Atenta para os diferentes modos de incorporação e transformação das chaulmoogras em conhecimentos validados cientificamente, tendo em vista a entrada em cena da 'chaulmoogra brasileira'. Privilegia a chegada dos derivados dessa planta à pauta de produção do Instituto Oswaldo Cruz (IOC), na década de 1920, estabelecendo nexos entre os diferentes processos produtivos e articulando-os ao contexto científico no período estudado. O óleo de chaulmoogra representou, até a década de 1940, a grande esperança para a tentativa de cura da lepra. Observa ainda que a terapêutica chaulmúgrica durante esse período, consolidou-se como um saber científico graças à realização de diversas pesquisas feitas em laboratórios de todo o mundo ocidental.

The article investigates how knowledge of medicinal plants and related treatment practices are assimilated and transformed. Taking as its focus the use of chaulmoogra oil to treat leprosy, it examines how information on this plant was incorporated and transformed into scientifically validated knowledge when 'Brazilian chaulmoogra' came onto the scene. Pointing to the addition of chaulmoogra byproducts to the Instituto Oswaldo Cruz's production agenda in the 1920s, the study establishes links between productive processes and relates these to the period's scientific context. From the late nineteenth century until the 1940s, chaulmoogra oil was the great hope in efforts to cure leprosy. During this period, chaulmoogric treatment earned a place as scientific knowledge thanks to research studies conducted in laboratories throughout the Western world.

[Chaulmoogra oil as scientific knowledge: the construction of a treatment for leprosy]. / O óleo de chaulmoogra como conhecimento científico: a construção de uma terapêutica antileprótica.

The article investigates how knowledge of medicinal plants and related treatment practices are assimilated and transformed. Taking as its focus the use of chaulmoogra oil to treat leprosy, it examines how information on this plant was incorporated and transformed into scientifically validated knowledge when 'Brazilian chaulmoogra' came onto the scene. Pointing to the addition of chaulmoogra byproducts to the Instituto Oswaldo Cruz's production agenda in the 1920s, the study establishes links between productive processes and relates these to the period's scientific context. From the late nineteenth century until the 1940s, chaulmoogra oil was the great hope in efforts to cure leprosy. During this period, chaulmoogric treatment earned a place as scientific knowledge thanks to research studies conducted in laboratories throughout the Western world.