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

Angiotensin-converting enzyme (ACE) plays a crucial role in the pathogenesis of hypertension. Piper sarmentosum Roxb., an herb known for its antihypertensive effect, lacks a comprehensive understanding of the mechanism underlying its antihypertensive action. This study aimed to elucidate the antihypertensive mechanism of aqueous extract of P. sarmentosum leaves (AEPS) via its modulation of the ACE pathway in phorbol 12-myristate-13-acetate (PMA)-induced human umbilical vein endothelial cells (HUVECs). HUVECs were divided into five groups: control, treatment with 200 µg/mL AEPS, induction 200 nM PMA, concomitant treatment with 200 nM PMA and 200 µg/mL AEPS, and treatment with 200 nM PMA and 0.06 µM captopril. Subsequently, ACE mRNA expression, protein level and activity, angiotensin II (Ang II) levels, and angiotensin II type 1 receptor (AT1R) and angiotensin II type 2 receptor (AT2R) mRNA expression in HUVECs were determined. AEPS successfully inhibited ACE mRNA expression, protein and activity, and angiotensin II levels in PMA-induced HUVECs. Additionally, AT1R expression was downregulated, whereas AT2R expression was upregulated. In conclusion, AEPS reduces the levels of ACE mRNA, protein and activity, Ang II, and AT1R expression in PMA-induced HUVECs. Thus, AEPS has the potential to be developed as an ACE inhibitor in the future.

Potential use of Lentinus squarrosulus mushroom as fermenting agent and source of natural antioxidant additive in livestock feed.

BACKGROUND: Fermenting feed has gained a lot of popularity in recent years owing to its renowned benefits to the livestock and feed quality. In the current study, Lentinus squarrosulus mushroom mycelium was tested for its potential as a fermenting agent and source of natural antioxidant in the feed. RESULTS: Phenolic content of methanolic and hot water extracts of the mycelium culture and its fermented maize ranged from 94.01 to 386.59 mg gallic acid equivalents g(-1) extract while the DPPH radical scavenging, CUPRAC, reducing power (RPA) and ß-carotene bleaching (BCB) antioxidant activity had EC50 values ranged from 15.30 to 120.3, 0.74 to 4.71, 1.86 to 13.5 and 0.01 to 0.21 mg mL(-1) , respectively. At 1.0-20.0 mg mL(-1) , the extracts retarded 21.02-55.35% of lipid deterioration. Pearson correlation analysis revealed the phenolic content of the extracts has moderate correlation with DPPH (r = 0.589) and RPA (r = 0.580), also a high correlation with BCB antioxidant activity (r = 0.872). In principal component analysis, DPPH, CUPRAC and RPA were seen to be clustered tightly together while BCB antioxidant activity was grouped with the phenolic content. CONCLUSION: Overall, L. squarrosulus mycelium functioned as antioxidants via several mechanisms, involving either electron transfer or hydrogen transfer-based reactions suggesting it as a promising fermentation agent to enhance feed nutrition and the fermented maize as a valuable feed resource.

Evaluation of Selected Culinary-Medicinal Mushrooms for Antioxidant and ACE Inhibitory Activities.

Considering the importance of diet in prevention of oxidative stress-related diseases including hypertension, this study was undertaken to evaluate the in vitro antioxidant and ACE inhibitory activities of selected culinary-medicinal mushrooms extracted by boiling in water for 30 min. Antioxidant capacity was measured using the following assays: DPPH free radical scavenging activity, ß-carotene bleaching, inhibition of lipid peroxidation, reducing power ability, and cupric ion reducing antioxidant capacity (CUPRAC). Antioxidant potential of each mushroom species was calculated based on the average percentages relative to quercetin and summarized as Antioxidant Index (AI). Ganoderma lucidum (30.1%), Schizophyllum commune (27.6%), and Hericium erinaceus (17.7%) showed relatively high AI. Total phenolics in these mushrooms varied between 6.19 to 63.51 mg GAE/g extract. In the ACE inhibitory assay, G. lucidum was shown to be the most potent species (IC(50) = 50 µg/mL). Based on our findings, culinary-medicinal mushrooms can be considered as potential source of dietary antioxidant and ACE inhibitory agents.