Quantified Piper sarmentosum Roxb. Leaves Aqueous Leaf Extract and Its Antihypertensive Effect in Dexamethasone-Induced Hypertensive Rats

Abstract

The quality control of raw herbal materials is important to ensure the safety, efficacy, and reproducibility of herbal products. Herbal products with consistent efficacy should be standardized and quantified based on their bioactive phytochemical compounds. Piper sarmentosum Roxb. has been reported for its antihypertensive activity. However, its antihypertensive effect on dexamethasone-induced hypertension still lacks information. In this study, the quality of two batches of raw P. sarmentosum leaf materials was assessed for heavy metal and microbial contents, and their aqueous extracts were assayed for antioxidant activity. The aqueous extract of the second batch of P. sarmentosum leaves was the only extract that passed the heavy metal and microbial limits and had the highest antioxidant activity (50.00 ± 2.88%); therefore, this extract was used for subsequent studies. The extract was quantified for two phytochemical markers, rutin (0.09 ± 0.002%) and vitexin (0.23 ± 0.007%), using a validated ultrahigh performance liquid chromatography method. The quantified extract (500 mg/kg/day orally) was able to lower the systolic blood pressure, diastolic blood pressure, and mean arterial pressure of dexamethasone-induced hypertensive rats comparable to the positive control drug, captopril. In summary, the quantified aqueous extract of P. sarmentosum based on rutin and vitexin lowers the blood pressure of dexamethasone-induced hypertensive rats, but its underlying mechanism warrants further investigation.

Piper sarmentosum Roxb. Attenuates Vascular Endothelial Dysfunction in Nicotine-Induced Rats

“…For instance, AEPS up to 300 μg/ml concentration did not reduce endothelial cell viability (Sundar et al, 2019). In rats, treatment with 500 mg/kg/day AEPS for 28 days did not cause any remarkable change in blood pressure (Alwi et al, 2018;Ugusman et al, 2020;Azmi et al, 2021). Besides, rat aorta displayed normal histology under light and electron microscopic examinations following AEPS treatment (Thent et al, 2012a;Thent et al, 2012b).…”

Piper sarmentosum Roxb. Inhibits Angiotensin-Converting Enzyme Activity in Phorbol 12-Myristate-13-Acetate-Induced Endothelial Cells

“…Human umbilical cords were collected after obtaining informed consent from healthy subjects in the labor room of Hospital Universiti Kebangsaan Malaysia. HUVECs were isolated from human umbilical cords via the collagenase perfusion technique as described previously [ 31 ]. Briefly, the cells were isolated from umbilical cords using 0.1% collagenase (Worthington Biochemical Corporation, Lakewood, NJ, USA) and cultured in endothelial cell medium (ScienCell Research Laboratories, Inc., San Diego, CA, USA) at 37 °C in a humidified atmosphere of 5% CO 2 and 95% air.…”

“…Furthermore, AEPS exhibits multiple cardiovascular protective effects, such as antidiabetic [ 19 ], antioxidant [ 25 ], anti-inflammatory [ 26 ], and anti-atherosclerotic effects [ 27 ]. The antihypertensive effect of AEPS has been validated in various hypertensive animal models, including spontaneously hypertensive rats [ 28 , 29 , 30 ], dexamethasone-induced hypertensive rats [ 31 , 32 ], and L-NAME-induced hypertensive rats [ 33 ]. A meta-analysis has demonstrated that AEPS supplementation significantly lowers systolic blood pressure, diastolic blood pressure and mean arterial pressure in hypertensive rat models [ 19 ].…”

Phenolics-Enhancing Piper sarmentosum (Roxburgh) Extracts Pre-Treated with Supercritical Carbon Dioxide and its Correlation with Cytotoxicity and α-Glucosidase Inhibitory Activities

“…They also reported that naringenin was absent in the extract. On the other hand, vitexin was reported at 0.23% in aqueous extract using a high-speed extractor machine at 80 °C for 3 hours (Azmi et al, 2021). Naringenin was previously reported from P. sarmentosum leaves methanol extract; however, data on the quantification of the chemical compound was not available (Subramaniam et al, 2003).…”