Avaliação do efeito bioinseticida dos extratos de Tabernaemontana catharinensis A.DC. (Apocynaceae) e Zeyheria montana Mart. (Bignoniaceae) sobre a mosca Zaprionus indianus (Díptera: Drosophilidae) (Gupta, 1970)

Zaprionus indianus (Díptera: Drosophilidae) (Gupta, 1970) is considered a potential pest-fly of commercial fruits in Brazil, particularly for cultivars of figs, star fruits and persimmons in  the southeast area. Considering the need of new alternatives for Z. indianus control, the aim of this work was to evaluate the insecticidal activity of ethanol extracts from Tabernaemontana catharinensis A.DC. (Apocynaceae: Tabernaemontana) stem bark and Zeyheria montana Mart. (Bignoniaceae: Zeyheria) leaves against different development stages of Z. indianus. Overall results showed that these extracts did not affect this fly in the adult stage, neither considering the total number of survivors when compared to control group or survival ratio by sex. However, they were effective in inhibiting the emergence of imagoes of Z. indianus, which could be of relevance for the control of this harmful fruit fly.  Zaprionus indianus (Díptera: Drosophilidae) (Gupta, 1970) é uma espécie de mosca invasora que tem se tornado uma praga relevante da cultura de figos, particularmente na região sudeste do Brasil. Salienta-se que a espécie, dita oportunista, apresenta grande potencial para o ataque de outros tipos de frutíferas, tais como o caqui e a carambola. Considerando a necessidade de busca por novas alternativas para o combate desta mosca, o objetivo deste estudo foi avaliar o efeito bioinseticida dos extratos etanólicos da casca do caule de Tabernaemontana catharinensis A.DC. (Apocynaceae) e das folhas de Zeyheria montana Mart. (Bignoniaceae) sobre as diferentes fases de desenvolvimento de Z. indianus. Neste contexto, quando considerada a fase adulta da mosca, os dados obtidos não revelaram um padrão de mortalidade diferencial para os tratamentos com os extratos, seja considerando o número de moscas vivas em relação ao grupo controle ou as diferenças absolutas nas taxas de sobrevivência por sexo, o que indica a ineficiência dos extratos contra Z. indianus na fase adulta. Entretanto, ambos os tratamentos afetaram seletivamente o grau de emergência de imagos de Z. indianus, o que pode ser de relevância no desenvolvimento de novas estratégias de combate a este inseto

Cloral hidratado: avaliação de risco à saúde humana como subproduto da desinfecção da água

No tratamento da água potável são utilizados produtos clorados de modo a garantir o nível de segurança sanitária exigido. Contudo, na presença de precursores, pode ocorrer a formação de Subprodutos da Desinfecção (SPD) em decorrência da reação com o cloro. O SPD Cloral Hidratado (CH), composto hipnótico e sedativo, tem sido encontrado na água, no entanto não é citado no padrão de potabilidade brasileiro. Este trabalho tem como objetivo geral avaliar o risco toxicológico do CH a partir de ensaios específicos e calcular um Valor Máximo Permissível (VMP). Roedores foram expostos a diferentes concentrações padronizadas de CH e submetidos a análises bioquímicas e bioensaios comportamentais e de locomoção, tais quais os de campo aberto, indução de sono e rotarod. Foi identificado o Nível de Efeito Adverso Não Observado (NOAEL) na dose 9,60 mg.kg-1.d-1, obtendo-se o VMP de 2,3 mg.L-1 de CH; considerando o Nível de Menor Efeito Observado (LOAEL) na dose 0,96 mg.kg-1.d-1, obteve- se o VMP de 0,023 mg.L-1 de CH, valor próximo ao 0,02 mg.L-1 citado nos padrões da Austrália (2017) e da Nova Zelândia (2017)

Isolation of flavonoids from Anemopaegma arvense (Vell) Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

Anemopaegma arvense pertence à família Bignoniaceae, sendo conhecida popularmente como Catuaba. Para avaliação de sua atividade citotóxica e antimicrobiana, a fração cromatográfica F3 e os flavonoides 1 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-glucopiranosídeo) (rutina) e flavonoide 2 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-galactopiranosídeo) foram isolados das folhas de A. arvense. A fração 3 e os flavonoides não apresentaram atividade antibacteriana. Nenhuma atividade citotóxica foi observada para a fração F3 e para os flavonoides, quando avaliados contra as células tumorais em teste. Entretanto, e considerando a atividade antifúngica, o flavonóide 1 apresentou valor de concentração inibitória mínima (CIM) de 0,5 mg/mL, enquanto o flavonóide 2, CIM de 0,25 mg/mL contra as cepas selvagem e mutante de Trichophyton rubrum, demonstrando, pela primeira vez, que os flavonoides isolados possuem atividade antifúngica, o que valida a mesma atividade para A. arvense.Anemopaegma arvense (Vell) Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside) (rutin) and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside) were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant). This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense

Gene Expression Response of Trichophyton rubrum during Coculture on Keratinocytes Exposed to Antifungal Agents

Trichophyton rubrum is the most common causative agent of dermatomycoses worldwide, causing infection in the stratum corneum, nails, and hair. Despite the high prevalence of these infections, little is known about the molecular mechanisms involved in the fungal-host interaction, particularly during antifungal treatment. The aim of this work was to evaluate the gene expression of T. rubrum cocultured with keratinocytes and treated with the flavonoid trans-chalcone and the glycoalkaloid α-solanine. Both substances showed a marked antifungal activity against T. rubrum strain CBS (MIC = 1.15 and 17.8 µg/mL, resp.). Cytotoxicity assay against HaCaT cells produced IC50 values of 44.18 to trans-chalcone and 61.60 µM to α-solanine. The interaction of keratinocytes with T. rubrum conidia upregulated the expression of genes involved in the glyoxylate cycle, ergosterol synthesis, and genes encoding proteases but downregulated the ABC transporter TruMDR2 gene. However, both antifungals downregulated the ERG1 and ERG11, metalloprotease 4, serine proteinase, and TruMDR2 genes. Furthermore, the trans-chalcone downregulated the genes involved in the glyoxylate pathway, isocitrate lyase, and citrate synthase. Considering the urgent need for more efficient and safer antifungals, these results contribute to a better understanding of fungal-host interactions and to the discovery of new antifungal targets

Essential oils of Citrus aurantifolia, Anthemis nobile and Lavandula officinalis: in vitro anthelmintic activities against Haemonchus contortus

Abstract Background Infections of sheep with gastrointestinal parasites, especially Haemonchus contortus, have caused serious losses in livestock production, particularly after the emergence of resistance to conventional anthelmintics. The search for new anthelmintic agents, especially those of botanical origin, has grown substantially due to the perspective of less contamination of meat and milk, as well as other advantages related to their cost and accessibility in less developed countries. The aim of this study was to evaluate the in vitro anthelmintic activity of essential oils of the plant species Citrus aurantifolia, Anthemis nobile and Lavandula officinalis against the main developmental stages of the parasite H. contortus. Results Plant species were selected based on substantial ethnopharmacological information. Analysis of the composition of each oil by gas chromatography coupled to mass spectrometry (GC-MS) demonstrated the presence of limonene (56.37%), isobutyl angelate (29.26%) and linalool acetate (35.97%) as the major constituents in C. aurantifolia, A. nobile and L. officinalis, respectively. Different concentrations of each oil were tested in vitro for their capacity to inhibit egg hatching (EHT), larval development (LDT) and adult worm motility (AWMT) using a multidrug-resistant strain of H. contortus (Embrapa 2010). The IC50 values obtained for the oils of C. aurantifolia, A. nobile and L. officinalis were 0.694, 0.842 and 0.316 mg/ml in the EHT and 0.044, 0.117 and 0.280 mg/ml in the LDT, respectively. The three oils were able to inhibit adult worm motility completely within the first 8–12 h of observation in the AWMT. Conclusions The present results demonstrate significant anthelmintic activity of the three oils against the different developmental stages of H. contortus. Furthermore, this study is of ethnopharmacological importance by validating the anthelmintic activity of the oils studied. Although new experiments are necessary, these data contribute to the development of pharmaceutical-veterinary products for sheep farming by opening up new therapeutic possibilities against gastrointestinal infections caused by H. contortus

Parawixin2 Protects Hippocampal Cells in Experimental Temporal Lobe Epilepsy

Epilepsy is considered as one of the major disabling neuropathologies. Almost one third of adult patients with temporal lobe epilepsy (TLE) do not respond to current antiepileptic drugs (AEDs). Additionally, most AEDs do not have neuroprotective effects against the inherent neurodegenerative process underlying the hippocampal sclerosis on TLE. Dysfunctions in the GABAergic neurotransmission may contribute not only to the onset of epileptic activity but also constitute an important system for therapeutic approaches. Therefore, molecules that enhance GABA inhibitory effects could open novel avenues for the understanding of epileptic plasticity and for drug development. Parawixin2, a compound isolated from Parawixia bistriata spider venom, inhibits both GABA and glycine uptake and has an anticonvulsant effect against a wide range of chemoconvulsants. The neuroprotective potential of Parawixin2 was analyzed in a model of TLE induced by a long-lasting Status Epilepticus (SE), and its efficiency was compared to well-known neuroprotective drugs, such as riluzole and nipecotic acid. Neuroprotection was assessed through histological markers for cell density (Nissl), astrocytic reactivity (GFAP) and cell death labeling (TUNEL), which were performed 24 h and 72 h after SE. Parawixin2 treatment resulted in neuroprotective effects in a dose dependent manner at 24 h and 72 h after SE, as well as reduced reactive astrocytes and apoptotic cell death. Based on these findings, Parawixin2 has a great potential to be used as a tool for neuroscience research and as a probe to the development of novel GABAergic neuroprotective agents

Dual RNA-Seq Analysis of Trichophyton rubrum and HaCat Keratinocyte Co-Culture Highlights Important Genes for Fungal-Host Interaction

The dermatophyte Trichophyton rubrum is the major fungal pathogen of skin, hair, and nails that uses keratinized substrates as the primary nutrients during infection. Few strategies are available that permit a better understanding of the molecular mechanisms involved in the interaction of T. rubrum with the host because of the limitations of models mimicking this interaction. Dual RNA-seq is a powerful tool to unravel this complex interaction since it enables simultaneous evaluation of the transcriptome of two organisms. Using this technology in an in vitro model of co-culture, this study evaluated the transcriptional profile of genes involved in fungus-host interactions in 24 h. Our data demonstrated the induction of glyoxylate cycle genes, ERG6 and TERG_00916, which encodes a carboxylic acid transporter that may improve the assimilation of nutrients and fungal survival in the host. Furthermore, genes encoding keratinolytic proteases were also induced. In human keratinocytes (HaCat) cells, the SLC11A1, RNASE7, and CSF2 genes were induced and the products of these genes are known to have antimicrobial activity. In addition, the FLG and KRT1 genes involved in the epithelial barrier integrity were inhibited. This analysis showed the modulation of important genes involved in T. rubrum–host interaction, which could represent potential antifungal targets for the treatment of dermatophytoses