Phenolic acids, found in cereals, legumes, vegetables, and fruits, have various biological functions. We aimed to compare the antihypertensive potential of different phenolic acids by evaluating their ACE inhibitory activity and cytoprotective capacity in EA.hy 926 endothelial cells. In addition, we explored the mechanism underlying the antihypertensive activity of sinapic acid. Of all the phenolic acids studied, sinapic acid, caffeic acid, coumaric acid, and ferulic acid significantly inhibited ACE activity. Moreover, gallic acid, sinapic acid, and ferulic acid significantly enhanced intracellular NO production. Based on the results of GSH depletion, ROS production, and MDA level analyses, sinapic acid was selected to study the mechanism underlying the antihypertensive effect. Sinapic acid decreases endothelial dysfunction by enhancing the expression of antioxidant-related proteins. Sinapic acid increased phosphorylation of eNOS and Akt in a dose-dependent manner. These findings indicate the potential of sinapic acid as a treatment for hypertension.

We comparatively evaluated the antioxidant properties of key triterpenes from Centella asiatica, including asiatic acid (AA), asiaticoside, madecassic acid, and madecassoside, in several cell types, including skin fibroblasts, macrophages, hepatocytes, and endothelial cells, under conditions promoting oxidative stress. AA conferred the highest viability on Hs68 cells exposed to ultraviolet B (UVB) irradiation. Triterpene pretreatment attenuated the UVB-induced generation of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as the UVB-induced depletion of glutathione (GSH) in skin fibroblasts. AA most potently inhibited UVB-induced MMP generation, resulting in increased intracellular collagen levels. Pretreatment with triterpenes, particularly AA, significantly improved cell viability and attenuated TBHP-induced levels of ROS, alanine aminotransferase, and aspartate aminotransferase in HepG2 cells. Triterpenes attenuated ROS levels and reduced MDA and GSH expression in EA.hy926 cells. In RAW264.7 macrophages, production of nitric oxide, tumor necrosis factor-α, and interleukin-6 (indicators of LPS-induced oxidative damage) was significantly reduced by treatment with any of the triterpenes. Statistical analyses of triterpene biological activities using principal component analysis and hierarchical clustering revealed that AA exerted the greatest overall influence and showed remarkable activity in Hs68 and HepG2 cells.

Unsaponifiable matter (USM) from perilla seed meal contains numerous phytochemicals, including tocopherols, phytosterols, squalene, and policosanols, that exhibit antioxidant and health-promoting properties. In this study, the protective effects of USM on UVB-induced skin aging were investigated in Hs68 cells. UVB irradiation decreased cell viability by 26% compared to the control. However, USM blocked UVB-induced cytotoxicity. Moreover, USM treatment significantly decreased the UVB-induced production of reactive oxygen species and attenuated the UVB-induced production and mRNA expression of matrix metalloproteinases (MMPs) by inhibiting the phosphorylation of mitogen-activated protein kinases and activator protein 1 (AP-1). Furthermore, UVB exposure led to a 49.4% reduction in collagen synthesis. However, USM treatment restored collagen synthesis through upregulation of the transforming growth factor beta (TGF-β)/Smad2/3 pathways. These data indicate that USM regulates the production of MMPs and collagen by modulation of the TGF-β/Smad pathway and AP-1 activity, suggesting that USM may be a useful anti-photoaging ingredient.

Centella asiatica possess various health-promoting activities owing to its bioactive compounds such as triterpenes, flavonoids, and vitamins. Ultrasound treatment during the post-harvest process is a good strategy for eliciting secondary metabolite in plants. The present study investigated the effect of ultrasound treatment for different time durations on the bioactive compounds and biological activities of C. asiatica leaves. The leaves were treated with ultrasound for 5, 10, and 20 min. Ultrasound elicitation (especially for 10 min) markedly elevated the accumulation of stress markers, leading to enhanced phenolic-triggering enzyme activities. The accumulation of secondary metabolites and antioxidant activities were also significantly improved compared with that in untreated leaves. In addition, ultrasound-treated C. asiatica leaves protected myoblasts against H₂O₂-induced oxidative stress by regulating reactive oxygen species production, glutathione depletion, and lipid peroxidation. These findings indicate that elicitation using ultrasound can be a simple method for increasing functional compound production and enhancing biological activities in C. asiatica leaves.

Ginseng seeds are rich in phytosterols, ginsenosides, and fatty acids, and can therefore be used in skincare to delay the aging process. Ginseng seed embryo (GSE) and ginseng seed coat (GSC) were separated from ginseng seeds (Panax ginseng Meyer). This study evaluated the protective activity and underlying mechanism of GSE and GSC on UVB irradiation-induced skin photoaging using Hs68 cells. Their bioactive compounds, including phytosterols, ginsenosides, tocopherols, tocotrienols, and fatty acids were determined by HPLC and GC. The levels of reactive oxygen species, matrix metalloproteinases (MMPs), and collagen levels were measured in human dermal fibroblast cell line, Hs68 cells. The antioxidant capacity and contents of total polyphenols and flavonoids were higher in GSC than those in GSE. Linoleic acid was the major fatty acid in both GSE and GSC. GSE and GSC treatment alleviated UVB-induced increase of reactive oxygen species (ROS), matrix metalloproteinase (MMP)-1, and MMP-3, resulting in reduced collagen degradation. Increased UVB-mediated phosphorylation of mitogen activated protein kinase (MAPK) and activator protein-1 (AP-1) was inhibited by GSE and GSC treatment. Moreover, GSE and GSC effectively upregulated transforming growth factor-β (TGF-β) 1 levels. It was found that ginseng seeds regulate the expression of TGF-β/Smad and MAPK/AP-1 pathways. Ginseng seeds contain various bioactive compounds and have protective activity against UVB-induced skin photoaging. Therefore, ginseng seeds have the potential for use in cosmeceutical preparations.

This study aimed to evaluate the effects of taxifolin and sorghum ethanol extract on free fatty acid (FFA)-induced hepatic insulin resistance. FFA treatment decreased glucose uptake by 16.2% compared with that in the control, whereas taxifolin and sorghum ethanol extract increased the glucose uptake. Additionally, taxifolin and sorghum ethanol extract increased the expression of p-PI3K, p-IRS1, p-AKT, p-AMPK, and p-ACC in FFA-induced hepatocytes. Furthermore, FFA treatment increased the expression of miR-195. However, compared with the FFA treatment, treatment with taxifolin and sorghum ethanol extract decreased miR-195 expression in a dose-dependent manner. Taxifolin and sorghum ethanol extract enhanced p-IRS1, p-PI3K, p-AMPK, p-AKT, and p-ACC expression by suppressing miR-195 levels in miR-195 mimic- or inhibitor-transfected cells. These results indicate that taxifolin and sorghum ethanol extract attenuate insulin resistance by regulating miR-195 expression, which suggests that taxifolin and sorghum ethanol extract may be useful antidiabetic agents.