Blood pressure-reducing activity of Gongronema latifolium Benth. (Apocynaeceae) and the identification of its main phytochemicals by UHPLC Q-Orbitrap mass spectrometry

Abstract

BackgroundGongronema latifolium Benth. (family Apocynaceae) leaves (GL) has interesting medicinal properties. The effects of extracts from G. latifolium on blood pressure (BP) and the possible mechanisms of action were also investigated.MethodsThe ultrahigh resolution liquid chromatography orbitrap MS analysis was used to identify the phytochemicals present. Normotensive Wistar rats were anesthetized with sodium pentobarbitone (40 mg/kg) intraperitoneally, and the jugular vein was cannulated for infusion of drugs while the carotid artery was cannulated for direct BP measurement. GL extract (5–20 mg) alone or with nifedipine (10 mg/kg), atropine (2 mg/kg), L-NAME (5 mg/kg), methyl blue (3 mg/kg) and propranolol (1 mg/kg) were administered intravenously to Wistar rats and direct BP measurements were carried out.ResultsSystolic and diastolic BP levels (128/90 mm Hg; MAP 103 ± 3 mm Hg) and heart rates were all significantly (p < 0.01) decreased after GL administration. Raised mean arterial pressure (MAP) and heart rate by atropine, L-NAME and methyl blue were significantly (p < 0.01) reduced after GL administration, while propranolol significantly (p < 0.01) inhibited hypotension caused by GL. Infusion of GL reduced MAP (95 ± 3 mm Hg) comparable with nifedipine (93 ± 2 mm Hg), a calcium channel blocker. The phytochemicals identified were 34 compounds, including oleanolic acid derivatives, flavonoids, antioxidant fatty acids, 2 coumarins and 2 iridoids.ConclusionsThese results suggest that G. latifolium has hypotensive properties mediated by the synergistic activity of the compounds, probably via the β-adrenergic blockade mechanism.

Gongronema latifolium leaf extract protects against dexamethasone‐induced myocardial cell injury via cardiac oxido‐inflammatory molecules modulation

“…This would have shown the blood pressure pattern and electrical activity in this model of myocardial injury. However, a previous study from our laboratory has shown that GL leaves extract has blood pressure lowering effect under normotensive conditions (Beshel et al, 2019). Also, the expression of apoptotic markers in the heart and liver was not measured.…”

“…This is in line with previous reports that the GL extract has anti‐lipid peroxidation and antioxidant properties which are attributed to the presence of phytochemicals such as alkaloid, saponin, tannins, and flavonoids (Okoko & Silas‐Olu, 2021). We previously demonstrated that the extract of GL leaf is rich in saponins, triterpenes, coumarins, and flavonoids, of which kaempferol and rutin were the most abundant (Beshel et al, 2019) that have antioxidant potentials.…”

“…The plant has hypoglycemic, hypolipidemic, and antioxidant properties (Ajiboye et al, 2019; Balogun et al, 2016), and it has been shown to reduce some cardiovascular risk factors (Okon et al, 2019). Phytochemical screening and Ultra‐high‐performance liquid chromatography performance on an ethanol extract of GL leaf from our laboratory revealed that it contains 34 compounds including flavonoid, alkaloid, saponins, and tannins (Beshel et al, 2019) which play a significant role in the body's defense mechanism against diseases caused by increased production of ROS and cardiovascular‐related disorders (Okesola et al, 2020).…”

Anti-inflammatory potentials of ethanolic leaf extract of Gongronema latifolium in streptozotocin induced diabetic rats

“…The decrease in the C-reactive protein levels in the two treated group is an indication of the anti-inflammatory potential of G. latifolium which may be due to the flavonoid and polyphenols in the plant extract [29]. A study reported that flavonoids present in G. latifolium leaves extract are kaempherol, kaempferol 3-O-rutinoside, rutin and laricitrin-3-Oglucoside [30]. Kaempferol and the rutinoside, and rutin have anti-inflammatory and antioxidant activity [31,32].…”

Galangin Attenuates Isoproterenol-Induced Inflammation and Fibrosis in the Cardiac Tissue of Albino Wistar Rats

“…phytochemicals maintains homodynamic function of heart rate and significantly prevents heart failure (Paulino et al, 2019;Beshel et al, 2019). During the MI development the cardiac membrane becomes damaged which has resulted in the outflow of cardiac tissue enzymes to the blood stream.…”