In vitro screening for growth inhibition activity on cancer cell lines of northern Chile highlands shrubs / Triagem in vitro da atividade de inibição do crescimento em linhagens celulares de câncer em arbustos das montanhas do norte do Chile

ABSTRACT: Cancer is still one of the leading causes of death worldwide. Many chemotherapeutics from plants have been tested in cancer, such as vinblastine and paclitaxel. The north of Chile, Arica & Parinacota region, is characterized by its vegetal biodiversity due to its unique geographical and climatological conditions, offering an unexplored and unique source of naturally-derived compounds. The present research has considered a screening of 26 highland herbs using an in vitro growth inhibition model in a panel of six cancer cell lines from different tissues. 5 of the 26 studied ethanolic extracts shows strong activity at least in one cell line when tested at 10 µg mL-1. We present a group of plants worthy to be evaluated as promissory extracts. This work is part of the systematic attempt to find new candidates to be used in cancer therapies.

RESUMO: O câncer ainda é uma das principais causas de morte no mundo. Muitos quimioterápicos de plantas foram testados em câncer, como vinblastina e paclitaxel. O norte do Chile, região de Arica e Parinacota, caracteriza-se por sua biodiversidade vegetal devido às suas condições geográficas e climatológicas únicas, oferecendo uma fonte inexplorada e única de compostos de origem natural. A presente pesquisa considerou uma triagem de 26 ervas das terras altas usando um modelo de inibição de crescimento in vitro em um painel de seis linhas celulares de câncer de diferentes tecidos. Cinco, dos 26 extratos etanólicos estudados, mostram forte atividade pelo menos em uma linhagem celular quando testados a 10 µg mL-1. Apresentamos um grupo de plantas dignas de serem avaliadas como extratos promissórios. Este trabalho faz parte da tentativa sistemática de encontrar novos candidatos para serem usados ​​em terapias contra o câncer.

Potential of Baccharis alnifolia Meyen & Walpan (Chilka) from northern Chile used as a medicinal infusion / Potencial de Baccharis alnifolia Meyen & Walpan (Chilka) do norte do Chile usado como infusão medicinal

ABSTRACT: Baccharis alnifolia Meyen & Walp. is a native and medicinal, Chilean Altiplano herb that is used as a poultice and also consumed as an infusion to relieve inflammation. This study evaluated the antioxidant and cytotoxic effect of the ethanolic extract of B. alnifolia and their infusion. It was reported that the ethanol extract contains 4.42 mg GAE/g of dry weight and the infusion contains 35.86 mg GAE/L of total polyphenols. Also, it determined the antioxidant capacity using Ferric reducing antioxidant power (FRAP), Oxygen Radical Absorbance Capacity (ORAC) and Trolox equivalent antioxidant capacity (TEAC) assay. Moreover, seven metabolites including between phenolic acids and flavonoids were identified for the first time in both extracts of the medicinal plant Baccharis alnifolia. The UHPLC-DAD chromatograms revealed the majority presence of ferulic acid and luteolin, both could be responsible for the antioxidant and cytotoxic activity. Furthermore, we realized a preliminary screening of cytotoxicity in different tumor cell lines, finding that these extracts have cytotoxic potential on kidney cells.

RESUMO: Baccharis alnifolia Meyen & Walp. é uma erva altiplana nativa e medicinal, chilena que é usada como cataplasma e também consumida como uma infusão para aliviar a inflamação. Este estudo avaliou o efeito antioxidante e citotóxico do extrato etanólico de B. alnifolia e sua infusão. Verificou-se que o extrato etanólico contém 4,42 mg GAE / g de peso seco e a infusão contém 35,86 mg GAE / L de polifenóis totais. Além disso, determinou a capacidade antioxidante utilizando o poder antioxidante redutor de Fração (FRAP), Capacidade de Absorção Radical de Oxigênio (ORAC) e capacidade antioxidante equivalente de Trolox (TEAC). Além disso, sete metabólitos, entre ácidos fenólicos e flavonóides, foram identificados pela primeira vez em ambos os extratos da planta medicinal Baccharis alnifolia. Os cromatogramas UHPLC-DAD revelaram a presença majoritária de ácido ferúlico e luteolina, ambos podendo ser responsáveis pela atividade antioxidante e citotóxica. Além disso, realizamos uma triagem preliminar da citotoxicidade em diferentes linhagens de células tumorais, descobrindo que esses extratos têm potencial citotóxico nas células renais.

Nutritional composition, antioxidant activity and isolation of scopoletin from Senecio nutans: support of ancestral and new uses.

Continuing with our study characterising Senecio nutans Sch. Bip., we have isolated and identified a simple coumarin, scopoletin, that could be relevant for the biological properties of the species related with the ancestral medical uses. This is the first report of scopoletin from S. nutans. In addition, the extract was analysed for its antioxidant activity using the ABTS and FRAP method as well as providing the first nutritional analyses of this plant from northern Chile highlands.

Identification and Characterization of the V(D)J Recombination Activating Gene 1 in Long-Term Memory of Context Fear Conditioning.

An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data using C57BL/6 mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor that introduces DSBs in immunoglobulin and T-cell receptor genes, is induced in the amygdala, but not in the hippocampus, after context fear conditioning. Amygdalar induction of RAG1 mRNA, measured by real-time PCR, was not observed in context-only or shock-only controls, suggesting that the context fear conditioning response is related to associative learning processes. Furthermore, double immunofluorescence studies demonstrated the neuronal localization of RAG1 protein in amygdalar sections prepared after perfusion and fixation. In functional studies, intra-amygdalar injections of RAG1 gapmer antisense oligonucleotides, given 1 h prior to conditioning, resulted in amygdalar knockdown of RAG1 mRNA and a significant impairment in LTM, tested 24 h after training. Overall, these findings suggest that the V(D)J recombination-activating gene 1, RAG1, may play a role in LTM consolidation.