In traditional Arabian medicine, the Rhus tripartita plant (family Anacardiaceae) has been used to treat inflammatory conditions. Although Rhus extracts have been reported for their cardioprotective effects, information regarding their active principle compounds remains insufficient. The present investigation was aimed at determining the antioxidant chemical constituents of the methanolic extract of R. tripartita stem bark and evaluating their ability to ameliorate methylglyoxal-induced endothelial cell apoptosis. Ten flavonoid compounds (1-10) were isolated and identified using DPPH radical scavenging bioassay-guided chromatographic separation. A new proanthocyanidin (rhuspartin) (1) was isolated and identified as 3,5,13,14-flavantetrol-(4β→8)-catechin, using extensive spectroscopic data and high resolution-mass spectrometry. Among the compounds (1, 5, 7-10) tested for toxicity toward cultured endothelial cells (HUVECs), the non-cytotoxic compounds 1 and 7 evinced cytoprotective potential that reversed the methylglyoxal-induced apoptosis (by 62% and 64%, respectively) through downregulation of caspase 3/7.

中文翻译：

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三叶漆树皮中的原花青素改善甲基环戊二醛诱导的内皮细胞凋亡

在传统的阿拉伯医学中，Rhus tripartita 植物（漆树科）已被用于治疗炎症。尽管已经报道了漆树提取物的心脏保护作用，但有关其活性成分的信息仍然不足。本研究旨在确定 R. tripartita 茎皮甲醇提取物的抗氧化化学成分，并评估其改善甲基乙二醛诱导的内皮细胞凋亡的能力。十种黄酮类化合物 (1-10) 使用 DPPH 自由基清除生物测定引导的色谱分离进行分离和鉴定。使用广泛的光谱数据和高分辨率质谱法，分离出一种新的原花青素 (rhuspartin) (1)，并将其鉴定为 3,5,13,​​14-flavantetrol-(4β→8)-catechin。