Polar compounds isolated from the leaves of Calea prunifolia H.B.K. and their anti-adrenergic related vasodilator activity

Abstract

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 CE 50 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 CE 50 from 2.3 × 10-8 to 1.3 × 10-7 and 8.0 × 10-7 mol L-1 , respectively.

The genus Calea L.: A review of isolated compounds and biological activities

“…Although these compounds were devoid of significant vasodilator activity when they were tested alone (1 μg mL , respectively. While a mixture of these three compounds exerted preventive anti-adrenergic activity, they did not show vasodilator activity (Puebla et al, 2011).…”

The genus Calea L.: A review on traditional uses, phytochemistry, and biological activities

“…The results showed that rutin (199), 3,5‐di‐ O ‐ E ‐caffeoylquinic acid and ent ‐15β‐(β‐D‐glucopyranosyloxy)‐kaur‐16‐en‐19‐oic acid β‐D‐glucopyranosyl ester exhibited no significant vasodilator effect when they were tested individually at concentration of 1.0 μg·ml −1 . However, a mixture of them in equal proportions (1:1:1) and own ethanol extract (1.0 μg·ml −1 ) showed preventive antiadrenergic activity (EC 50 = 1.3 × 10 −7 and 8.0 × 10 −7 mol·L −1 , respectively), suggesting a synergistic interaction among these polar components (Puebla et al, ).…”

“…Calea L. genus belongs to Melampodiinae subtribe, Heliantheae tribe, and Asteroideae subfamily, which is the most diverse subfamily from Asteraceae (=Compositae) (Pruski & Urbatsch, ; Puebla et al, ). This genus is well‐known, comprising approximately 125 species widely distributed in tropical and subtropical regions of the New World (Roque & Carvalho, ).…”

“…DC. to cure oliguria, gastric ulcers, and other inflammatory injuries (Borges del Castillo et al, ), and Calea glomerata Klatt and Calea prunifolia Kunth are utilized in colombian folk medicine for treating arterial hypertension (Guerrero et al, ; Onzaga, Rincón, & Guerrero, ; Puebla et al, ). In addition to these indications, antibacterial (Borges del Castillo et al, ), giardicidal, and amebicidal effects have also been described (Ferreira, Roque, Gottlieb, Oliveira, & Gottleib, ; Kato et al, ).…”

“…199), 3,5-di-O-E-caffeoylquinic acid and ent-15β-(β-D-glucopyranosyloxy)-kaur-16-en-19-oic acid β-Dglucopyranosyl ester exhibited no significant vasodilator effect when they were tested individually at concentration of 1.0 μg·ml −1 . However, a mixture of them in equal proportions (1:1:1) and own ethanol extract (1.0 μg·ml −1 ) showed preventive antiadrenergic activity (EC 50 = 1.3 × 10 −7 and 8.0 × 10 −7 mol·L −1 , respectively), suggesting a synergistic interaction among these polar components(Puebla et al, 2011).Butanol-containing fraction from leaves of C. prunifolia (0.1-100 μg·ml −1 ) was examined for its cardiovascular effects on two different rat preparations (conscious and anesthetized). Results of this work revealed that this fraction possesses vasorelaxant action on rat aortic smooth muscle contracted by phenylephrine (IC 50 = 58 μg·ml −1 ) and was able to decrease contractile response induced by noradrenaline in vas deferens, displaying a competitive antagonism profile [pA 2 = 4.48, slope (m) = 1024] and a hypotensive effect in a dose-dependent manner in the anesthetized normotensive rats (1-100 mg·kg −1 ).…”