Evaluation of aqueous extract of syzygium polyanthum leaves as anti-hypertensive agent in spontaneous hypertensive rat (SHR)
Year: 2021
Type: dissertation
Abstract: Hypertension is associated with significant morbidity and mortality. The use \nof medicinal herbs as alternative medicines to manage hypertension is increasing \nexponentially. Syzygium polyanthum, has been claimed traditionally as an \nantihypertensive agent. This study aimed to determine the antihypertensive effects of \nthe aqueous extract of S. polyanthum (AESP) leaves and its mechanisms using \nspontaneously hypertensive rats (SHR). The phytochemical profiling, antioxidant \nproperties and antihypertensive activity were evaluated. Fifty male SHR were divided \nequally into 5 groups; untreated-SHR, Losartan-treated, 3 groups of AESP-treated \nwith different dosages (1500 mg/kg, 1750 mg/kg and 2250 mg/kg), and 10 male WKY \nrats as control. All treatments were given orally for 12th weeks. Systolic blood pressure \n(SBP) was measured biweekly. Whereas, the biochemical analysis, oxidative stress \nmarkers and angiotensin-converting enzyme (ACE) level were evaluated at the end of \nthe study. The histology of thoracic aorta and kidney were assessed using \nhaematoxylin & eosin (H&E) staining, and scanning electron microscope (SEM). \nAESP contains flavonoids and phenols with gallic acid detected. AESP showed high \nin vitro antioxidant and ACE-inhibitory activities. In AESP-treated SHR; SBP reduced \nsignificantly, improved renal function and oxidative stress markers. However, only \nAESP (2250 mg/kg) significantly reduced ACE concentration. There was also \nhistology improvement of the thoracic aorta and renal in AESP-treated SHR. Hence, \nthe study suggests that antihypertensive properties of AESP are due to its antioxidant(mainly gallic acid) and ACE inhibitory activity. Thus, this study reveals the \nantihypertensive mechanism of AESP exerted inhibitory activity through suppression \nof the ACE action which might involved RAAS pathway.
Author: Nurul Syahida Ramli
Language: English
Topic: Medicinal Plant Research
Subfield: Plant Science
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W3200886295