ABSTRACT
BACKGROUND: Butyrate is a histone deacetylase inhibitor that induces apoptosis and inhibits cell proliferation of colorectal cancer cells. To improve its anticancer activity, butyrate has been evaluated mixed with drugs and different molecules. Plant antimicrobial peptides are attractive anticancer alternative molecules because they show selective cytotoxic activity against different cancer cell lines. In this work, we explore if the plant defensin c-thionin (Capsicum chinense) can improve butyrate activity on Caco-2 cell line and we also determined the mechanism of death activated. RESULTS: The combined treatment of c-thionin (3.5 mM) and butyrate (50 mM) showed higher cytotoxicity on Caco-2 cells with respect to single treatments. Also, the combined treatment reduced cell proliferation and exhibited a higher rate of apoptosis than single treatments. Combined treatment induced caspases 8 and 9 activation to an extent comparable with that of butyrate while c-thionin did not activate caspases. Additionally, reactive oxygen species generation preceded the onset of apoptosis, and superoxide anion production was higher in cells treated with the combined treatment. CONCLUSIONS: The c-thionin from Habanero chili pepper improved the butyrate cytotoxicity on Caco-2 cells. This effect occurred through apoptosis induction associated with reactive oxygen species production. Therefore, the combination of butyrate with cytotoxic antimicrobial peptides could be an attractive strategy for cancer therapy.
Subject(s)
Humans , Butyrates , Capsicum/chemistry , Adenocarcinoma , Colonic Neoplasms , Cell Cycle , Reactive Oxygen Species , Apoptosis , Caco-2 Cells , Defensins , ThioninsABSTRACT
Abstract Background: The most common ocular disease affecting cattle worldwide is infectious bovine keratoconjunctivitis (IBK), which has been associated with Moraxella bovis bacterium. Objective: To report the molecular characterization of the ocular bacterial microbiota and its relation to IBK in cattle in two dairy regions in Michoacán, Mexico. Methods: A total population of 761 bovines were evaluated, of which 17 (2.23%) showed symptoms of IBK. Thirty-eight bacterial isolates from ocular samples of bovines with IBK were characterized by Gram-staining and antimicrobial sensitivity. In addition, isolates were identified by sequence comparisons of the 16S ribosomal gene. Results: The genus Moraxella was one of the most abundant bacteria and M. bovoculi was the most predominant species. Conclusion: The bacterial isolates identified in eye lesions of cattle and associated to IBK are diverse. To the author´s knowledge, this is the first study on the subject in Mexico; therefore, more research is needed to estimate the incidence of IBK and determine its associated microbiota.
Resumen Antecedentes: la enfermedad ocular más común que afecta al ganado en todo el mundo es la queratoconjuntivitis infecciosa bovina (IBK), que se ha asociado con la bacteria Moraxella bovis. Objetivo: reportar la caracterización molecular de la microbiota bacteriana ocular y su relación con IBK en ganado de dos regiones lecheras en Michoacán, México. Métodos: se evaluó una población total de 761 bovinos de los cuales 17 (2,23%) mostraron síntomas de IBK. Se obtuvieron treinta y ocho aislamientos bacterianos de muestras oculares de bovinos con IBK, los cuales se caracterizaron por tinción de Gram y sensibilidad antimicrobiana. Además, los aislamientos se identificaron mediante comparaciones de secuencias del gen ribosomal 16S. Resultados: el género Moraxella fue una de las bacterias más abundantes y M. bovoculi fue la especie más predominante. Conclusión: los aislamientos bacterianos identificados en lesiones oculares de bovinos y asociados a IBK son diversos. Hasta donde sabemos, este es el primer estudio sobre el tema realizado en México; por lo tanto, es necesario ampliar esta investigación para estimar la incidencia de IBK y determinar la microbiota asociada con la misma.
Resumo Antecedentes: a doença ocular mais comum que afeta o gado no mundo é a ceratoconjuntivite bovina (IBK), que tem sido associada à bactéria Moraxella bovis. Objetivo: relatar a caracterização molecular da microbiota bacteriana ocular e sua relação com a IBK em bovinos de duas regiões leiteiras de Michoacán, México. Métodos: foi avaliada uma população total de 761 bovinos, más apenas 17 (2,23%) apresentaram sintomas de IBK. Trinta e oito isolados bacterianos de amostras de olho bovino com IBK foram caracterizados por coloração de Gram e sensibilidade antimicrobiana. Além disso, os isolados foram identificados por comparação de sequências do gene ribossômico 16S. Resultados: a microbiota bacteriana associada à IBK foi diversa, sendo o gênero Moraxella uma das mais abundantes e M. bovoculi a espécie predominante. Conclusão: de acordo com o conhecimento dos autores, este é o primeiro estudo sobre o tema no México até o momento, portanto é necessário expandir essa pesquisa para estimar a incidência de IBK e determinar a microbiota associada à mesma.
ABSTRACT
Background: The actions of plant antimicrobial peptides (PAP) against intracellular pathogens are poorly known. It has been reported that wheat puroindolines show antibacterial activity against Staphylococcus epidermidis endocyted by macrophages. In this work, we evaluated the intracellular antimicrobial activity of PAP gamma-thionin and thionin Thi2.1 produced by bovine endothelial cells against intracellular Staphylococcus aureus and Candida albicans. We used three host-pathogen models: 1) bovine mammary epithelial cells (BMEC)-S. aureus, 2) bovine endothelial cells (BEC)-S. aureus and 3) BEC-C. albicans, and evaluated the effect of conditioned media from BEC producers of PAP (gamma-thionin and thionin Thi2.1). Results: In the first model, conditioned medium (CM) containing Thi2.1 completely inhibited S. aureus intracellular after 24 hrs treatment. In the second model, CM from BEC containing gamma-thionin has a better effect killing intracellular S. aureus for 12-24 hrs incubations than CM from endothelial cells producers of Thi2.1; this was related with an increase of nitric oxide production (~2 times) in BEC infected and treated for 12 hrs with CM containing gamma-thionin, which negatively correlates with bacterial viability. In the third model, CM containing Thi2.1 showed a more potent intracellular fungicidal activity (~85 percent of inhibition) at 24 hrs treatment than CM containing gamma-thionin (~35 percent of inhibition). Conclusions: This work shows new effects of PAP to control intracellular bacterial or fungal infections.