Cellular and molecular effects of Baccharis dracunculifolia D.C. and Plectranthus barbatus Andrews medicinal plant extracts on retinoid metabolism in the human hepatic stellate cell LX-2.

BACKGROUND: Chronic hepatic diseases are serious problems worldwide, which may lead to the development of fibrosis and eventually cirrhosis. Despite the significant number of people affected by hepatic fibrosis, no effective treatment is available. In the liver, hepatic stellate cells are the major fibrogenic cell type that play a relevant function in chronic liver diseases. Thus, the characterization of components that control the fibrogenesis in the hepatic stellate cells is relevant in supporting the development of innovative therapies to treat and/or control liver fibrosis. The present study investigated the effects of Baccharis dracunculifolia D.C. and Plectranthus barbatus Andrews medicinal plant extracts in LX-2 transdifferentiation. METHODS: LX-2 is a human immortalized hepatic stellate cell that can transdifferentiate in vitro from a quiescent-like phenotype to a more proliferative and activated behavior, and it provides a useful platform to assess antifibrotic drugs. Then, the antifibrotic effects of hydroalcoholic extracts of Baccharis dracunculifolia and Plectranthus barbatus medicinal plants on LX-2 were evaluated. RESULTS: The results in our cellular analyses, under the investigated concentrations of the plant extracts, indicate no deleterious effects on LX-2 metabolism, such as toxicity, genotoxicity, or apoptosis. Moreover, the extracts induced changes in actin filament distribution of activated LX-2, despite not affecting the cellular markers of transdifferentiation. Consistent effects in cellular retinoid metabolism were observed, supporting the presumed activity of the plant extracts in hepatic lipids metabolism, which corroborated the traditional knowledge about their uses for liver dysfunction. CONCLUSION: The combined results suggested a potential hepatoprotective effect of the investigated plant extracts reinforcing their safe use as coadjuvants in treating imbalanced liver lipid metabolism.

New chemical evidence for the ability to generate radical molecular ions of polyenes from ESI and HR-MALDI mass spectrometry.

We report here new chemical evidence for the generation of radical molecular ions of compounds with a conjugated pi-system (polyene) in ESI and HR-MALDI mass spectrometry. The oxidation potential of the neutral polyenes was calculated by cyclic-voltammetry and the results compared with those previously published for other complex conjugated compounds that have also been shown to form M*+ in ESI-MS. This study clearly demonstrates the correlation between the oxidation potential and the formation of the M*+ for the polyenes studied.

La prevención química del cáncer / The chemoprevention of cancer

El objetivo de este trabajo fue evaluar el concepto, la situación actual y las perspectivas en la prevención química del cáncer. Para dicho análisis se consideraron los mecanismos involucrados en el proceso, las características que requieren los compuestos para ubicarlos en estudios preclínicos y clínicos, y el estado actual en que se encuentran agentes como los retinoides, carotenoides, calcio, ácido alérgico y fumárico, curcumino y aspirina. La información sugiere que la estrategia planteada tiene bases sólidas y que en un futuro cercano se verán efectos positivos en el hombre

Bases para el uso combinado de los interferones y de los retinoides en oncología clínica / Basis for the combined use of interferon and retinoid in clinical oncology

El acido retinoico y el interferón alfa tienen actividad limitada en el tratamiento de cáncer avanzado. La información obtenida de los cultivos celulares indican que, en combinación, estos agentes tienen incremento de la actividad biológica modulando el crecimiento y la diferenciación en un número de tipos celulares malignos. Trabajos clínicos recientes sobre el tratamiento de algunos carcinomas avanzados de células escamosas informan actividad terapéutica con este régimen. Este artículo revisa los datos preclínicos obtenidos al evaluar el ácido retinoico en combinación con interferones