ABSTRACT Plants are considered among the main sources of biologically active chemicals. The species Solidago chilensis Meyen, Asteraceae, is native to the southern parts of South America, where the aerial parts of the plant are commonly used for the treatment of inflammatory conditions. However, the effects of S. chilensis on human cancer cells remain to be elucidated. In this study, we evaluated the antiproliferative effects of the hydroalcoholic and dichloromethane extracts of S. chilensis, as well as their chemical constituents quercitrin and solidagenone against the five human tumor cell lines in vitro. The dichloromethane extract showed a promisor antiproliferative effects in vitro, especially against glioma cell line. Besides, the hydroalcoholic extract and quercitrin were inactive. The diterpene solidagenone showed highly potent antiproliferative effects against breast (MCF-7), kidney (786-0), and prostate cancer (PC-3) cells (total growth inhibition: TGI < 6.25 µg/ml). Solidagenone meets the theoretical physico-chemical criteria for bioavailability of drugs, according to the "Rule of Five" and, by theorical studies, the observed biological effects were probably related to the interaction of the molecule with nuclear receptors and as an enzymatic inhibitor. This study contributes to chemical study and to the identification of antiproliferative molecules in S. chilensis.

RESUMEN Antecedentes: Passiflora quadrangularis L. es una de las especies utilizadas en medicina tradicional en Colombia para la hipertensión pero hasta el momento no se ha evaluado en modelos experimentales. Objetivos: Evaluar la capacidad del extracto etanólico de P. quadrangularis L. para prevenir la hipertensión y el remodelado vascular inducidos por déficit de óxido nítrico (NO) en ratas Wistar. Métodos: El inhibidor de la óxido nítrico (NO) sintasa L-NAME (10 mg/kg, i.p, cada 48 h) se administró durante siete semanas a los siguientes grupos de tratamiento: P. quadrangularis L. 75, 150 y 300 mg/kg/d, p.o; Enalapril como agente de referencia, 10 mg/kg/d, p.o., y vehículo como control (mezcla de propilenglicol 10%, glicerina 10% y polisorbato 2%). Se midió la presión arterial (BP) y la frecuencia cardiaca (HR) dos veces por semana. Después del sacrificio, se aislaron los anillos aórticos, se desencadenó la contracción con fenilefrina (PE 10-6 M) y la respuesta relajante con concentraciones acumulativas de acetilcolina (ACh, 10-10 - 10 -5 M) o nitroprusiato de sodio (SNP, 10-10 - 10 -5 M). También se realizaron estudios histopatológicos de la relación entre el espesor y el lumen tanto en el ventrículo izquierdo como en las paredes de la aorta, así como un cribado fitoquímico. Resultados: Enalapril y todas las dosis de P. quadrangularis L. evitaron la hipertensión inducida por L-NAME (122 ± 1,2 frente a 155 ± 1,3 mm Hg a la séptima semana). P. quadrangularis L. aumentó significativamente el efecto relajante inducido por ACh en la aorta aislada y disminuyó la relación entre el espesor y la luz de los especímenes en la pared de la aorta. Conclusiones: P. quadrangularis L. previene la hipertensión experimental inducida por déficit de óxido nítrico en ratas, mejorando la respuesta del endotelio y protegiendo frente al remodelado vascular.

ABSTRACT Background: Passiflora quadrangularis L. is among the species used in Colombian folk medicine for hypertension, but until now it has not been studied in experimental models. Objectives : To assess the capacity of P. quadrangularis L. EtOH extract to prevent the hypertension and vascular remodelling induced by nitric oxide (NO) deficit in Wistar rats. Methods: The nitric oxide (NO) synthase inhibitor L-NAME (10 mg/kg, i.p (intraperitoneal), every 48h) was administered for seven weeks to the following groups of rats: P. quadrangularis L.75, 150 and 300 mg/kg/d, p.o. (oral route); enalapril as reference agent, 10 mg/kg/d, p.o. and vehicle as control (mixture of propylene glycol 10%, glycerine 10% and polysorbate 2%). Arterial blood pressure (BP) and heart rate (HR) were measured twice a week. After sacrifice, the aortic rings were isolated, contraction was triggered with phenylephrine (PE 10-6 M) and then the relaxant response achieved with cumulative concentrations of acetylcholine (ACh, 10-10 - 10-5 M) or sodium nitroprusside (SNP, 10-10 - 10-5 M) was assessed. Histopathologic measures of thickness/lumen ratio from both the left ventricle and aorta walls, as well as phytochemical screening, were also performed. Results: As for enalapril, all doses of P. quadrangularis L. prevented the hypertension induced by L-NAME (122±1.2 versus 155±1.3 mmHg at seventh week). P. quadrangularis L. significantly increased the relaxant effect induced by ACh in isolated aorta and decreased the thickness/lumen ratio of aorta wall specimens. Conclusions: P. quadrangularis L. prevents experimental hypertension induced in rats with nitric oxide deficits improving the endothelium vasodilatation response and protecting against vascular remodelling.

As folhas da Calea prunifolia H.B.K., espécie usada na medicina popular da Colômbia para a hipertensão, foram analisadas quanto à composição química, resultando no isolamento de um glicosídeo flavonóico, um derivado do ácido quínico e um glicosídeo diterpênico com esqueleto do tipo caurano. As estruturas químicas foram elucidadas por análise espectral, incluindo dados de HRMS e RMN 1D e 2D. A atividade anti adrenérgica dos três compostos foi avaliada. O efeito vasodilatador relacionado com a atividade anti adrenérgica dos três compostos foi avaliada em anéis de aorta isolada de ratos Wistar, contraídos cumulativamente com fenilefrina (de 1 × 10-9 a 5 × 10-5 mol L-1). Embora esses compostos não tenham apresentado atividade vasodilatadora significativa quando testados isoladamente (1 µg mL-1), misturas deles (1:1:1) e o próprio extrato de EtOH exerceu atividade anti adrenérgica preventiva, aumentando a CE50 da fenilefrina, de 2,3 × 10-8 para 1,3 × 10-7 e 8,0 × 10-7 mol L-1, respectivamente.

The leaves of Calea prunifolia H.B.K., medicinal specie used in Colombian folk medicine for hypertension have been analysed for their chemical constituents, resulting in the isolation of one flavonoid glycoside, one quinic acid derivative and one kaurane diterpenoid glycoside. Their chemical structures were elucidated on the basis of spectral analysis, including HRMS, 1D- and 2D-NMR data. The vasodilator effect related to anti adrenergic activity of the three compounds was evaluated in isolated aortic rings from Wistar rats contracted cumulatively with phenylephrine (from 1× 10-9 to 5 × 10-5 mol L-1). Although these compounds were devoid of significant vasodilator activity when they were tested alone (1 µg mL-1), mixtures of them (1:1:1) and the own EtOH extract exerted preventive anti-adrenergic activity increasing the phenylephrine CE50 from 2.3 × 10-8 to 1.3 × 10-7 and 8.0 × 10-7 mol L-1, respectively.