Vasorelaxant activity and acute toxicity of the ethanolic extract of Zanthoxylum rhoifolium Lam leaves

Joliane Carvalho Silva,Gabriela Dantas Carvalho,Aldeídia Pereira De Oliveira,Fabiana De Moura Souza,Mariana Helena Chaves,Pedro Simão Da Silva Azevedo,Marcelo Bezerra Mendes,Carla Kelly Barroso Sabino,Ilmara Cecília Pinheiro Morais,Kalynca Kayla Viana Aragão

doi:10.1590/s2175-97902019000117754

Abstract

The study evaluated the vasorelaxant effect induced by the ethanolic extract of the leaves of Zanthoxylum rhoifolium Lam (EEtOH-Zr/leaves). Wistar rats were treated with the leaf extract containing a single dose of 2,000 mg / kg, v.o. After 14 days, the animals were anesthetized for blood collection and subsequent analysis of the biochemical parameters; they were then euthanized (sodium pentobarbital-100 mg/kg, i.p.) for the removal and morphological analysis of the heart, lung, liver and kidney. The vasorelaxation activity the and vascular reactivity of EEtOH-Zr/leaves were evaluated on artery mesenteric rings isolated from rats. The extract showed no signs of toxicity and no significant difference in the values of the biochemical parameters between the control group and the group of treated animals. In the evaluation of pharmacological activity in the smooth muscle, the EEtOH-Zr/leaves caused vasorelaxant effect on the tonic contraction induced by phenylephrine in mesenteric artery preparations in the presence (pD2=2.17±0.05 µg/mL; Emax=99.8±5.2%) and absence (pD2=2.14±0.05 µg/mL; Emax=95.3±6.4%) of the vascular endothelium. Oral administration of EEtOH-Zr/leaves reduced the contraction induced by the cumulative addition of PHE. It is concluded that the EEtOH-Zr/leaves promote vasorelaxation and reduce vascular reactivity of adrenergic alpha-1 agonist in the mesenteric artery. The results did not show toxic effects of the extract.

Highlights

Cardiovascular disorders are the leading cause of morbidity and mortality worldwide (Hoyert, Xu, 2012). 25% of adults suffer from this disease and this number will reach 29% by 2025 (Kearney et al, 2005)
There was no significant difference between the values of biochemical parameters observed in the serum of the control group compared with the group treated with EEtOH-Zr/leaves (Figure 5)
In the evaluation of pharmacological activity on the vascular smooth muscle, the main observation is that EEtOH-Zr/leaves promoted a vasorelaxant effect dependent on the concentration and independent on the vascular endothelium in mesenteric artery rings precontracted with phenylephrine (Figure 3)

Summary

Introduction

Cardiovascular disorders are the leading cause of morbidity and mortality worldwide (Hoyert, Xu, 2012). 25% of adults suffer from this disease and this number will reach 29% by 2025 (Kearney et al, 2005). Lowering blood pressure greatly reduces the risks of developing heart failure, coronary diseases, renal damages and cerebral vascular diseases (Ezzati et al, 2002). Most of these disorders are untreatable and the current pharmacological strategies only aim at the disease control (Canto, Kiefe, Greenland, 2012). There is a growing trend towards using medicinal plants in health care in general medicine, in cardiovascular medicine (Imanshahidi, Hosseinzadeh, 2008). The reputation of plants in saving human beings has a long history, cutting across different cultures in the world (Hosseinzadeh et al, 2015). In Brazil, the use of medicinal plants by the population in order to treat diseases was always expressive, mainly due to the extensive and diverse flora (Pasa, 2011). Secondary metabolites extracted from these plants raise great interest due to their pharmacological activities and healing potential (Pereira, Cardoso, 2012)

Methods

Results

Conclusion