Cochlospermum vitifolium induces vasorelaxant and antihypertensive effects mainly by activation of NO/cGMP signaling pathway

Aim of the studyCochlospermum vitifolium is a medicinal plant used for the treatment of diabetes, hepatobilary and cardiovascular illnesses. The aim of current study was to determine the in vivo antihypertensive and in vitro functional vasorelaxant mechanism of methanol extract of Cochlospermum vitifolium (MECv) and naringenin (NG).Materials and methodsTest material was assayed on rat isolated aorta rings test with- and without-endothelium to determine their vasorelaxant mechanism. Also, the in vivo antihypertensive effect was evaluated on spontaneously hypertensive rat (SHR) model. In addition, presence of NG into the extract was confirmed by reverse phase high performance liquid chromatography (RP-HPLC) analysis.ResultsMECv (120 mg/kg) and NG (50 and 160 mg/kg) showed acute antihypertensive effects on SHR when systolic and diastolic pressure were decreased at 1 h and 24 h after administration, respectively. Vasorelaxant effect of MECv and NG was shifted to the right when endothelium-intact aortic rings were pre-incubated with L-NAME (10 μM) and ODQ (1 μM). Also, NG relaxant curves were displaced to the right in the presence of tetraethylammonium (TEA, 1 mM) and 2-aminopyridine (2-AP, 100 μM) on endothelium-denuded aortic rings.ConclusionExperiments described above showed that MECv play an important role in hypertension regulation through NO synthesis and may be PGI2 production and potassium channel activation on excessive endothelial dysfunction conditions. Unfortunately, presence of NG into the extract is not significant on bioactivity of the extract; however, this compound could be tested and evaluated as structural scaffold for future drug design for development of antihypertensive agents.

Graphical abstractMethanolic extract of Cochlospermum vitifolium (MECv) induced antihypertensive effect on SHR by NO/cGMP signaling pathway.Figure optionsDownload full-size imageDownload as PowerPoint slide