Institute of Cardiovascular Diseases, Jiangxi Academy of Clinical Medical Sciences, the First Affiliated Hospital of Nanchang University, Nanchang 330006, China.
Jiangxi Provincial Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang 330006, China.
Chin J Nat Med. 2022 Jan;20(1):22-32. doi: 10.1016/S1875-5364(21)60110-3.
Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine. Its primary therapies include clearing heat and detoxification, activating blood circulation, and removing blood stasis. Lonicera japonica flos (LJF) has long been known as an excellent antipyretic and antidote. Luteoloside (Lut) is one of the main components of LJF and exhibits antioxidant, anti-inflammatory, and cytoprotective properties. However, the protection of Lut against iron overload injury and its underlying mechanisms remain unclear. Therefore, HUVECs were exposed to 50 μmol·L iron dextran for 48 h to establish an iron overload damage model and the effects of Lut were assessed. Our results showed that 20 μmol·L Lut not only increased cell viability and weakened LDH activity, but also significantly up-regulated DDAHⅡ expression and activity, increased p-eNOS/eNOS ratio and NO content, and reduced ADMA content in HUVECs exposed to iron overload. Furthermore, Lut significantly attenuated intracellular/mitochondrial ROS generation, improved SOD, CAT, and GSH-Px activities, reduced MDA content, maintained MMP, inhibited mPTP opening, prevented cyt c from mitochondria released into cytoplasm, reduced cleaved-caspase3 expression, and ultimately decreased cell apoptosis induced by iron overload. The effects of Lut were similar to those of L-arginine (an ADMA competitive substrate), cyclosporin A (a mPTP blocker agent), and edaravone (a free radical scavenger) as positive controls. However, addition of pAD/DDAH II-shRNA adenovirus reversed the above beneficial effects of Lut. In conclusion, Lut can protect HUVECs against iron overload injury via the ROS/ADMA/DDAH II/eNOS/NO pathway. The mitochondria are the target organelles of Lut's protective effects.
铁过载损伤被认为是中医痹症血瘀证的一部分。其主要治疗方法包括清热解毒、活血化瘀。金银花（LJF）一直被认为是一种很好的解热解毒剂。木犀草苷（Lut）是 LJF 的主要成分之一，具有抗氧化、抗炎和细胞保护作用。然而，Lut 对铁过载损伤的保护作用及其机制尚不清楚。因此，我们将 HUVEC 暴露于 50μmol·L 铁右旋糖苷 48 h 以建立铁过载损伤模型，并评估 Lut 的作用。我们的结果表明，20μmol·L Lut 不仅增加了细胞活力并减弱了 LDH 活性，而且还显著上调了 DDAHⅡ的表达和活性，增加了 p-eNOS/eNOS 比值和 NO 含量，降低了 HUVEC 中铁过载时 ADMA 的含量。此外，Lut 显著减轻了细胞内/线粒体 ROS 的产生，提高了 SOD、CAT 和 GSH-Px 的活性，降低了 MDA 含量，维持了 MMP，抑制了 mPTP 的开放，防止了 Cyt c 从线粒体释放到细胞质中，减少了裂解 caspase3 的表达，最终减少了铁过载引起的细胞凋亡。Lut 的作用与 L-精氨酸（ADMA 的竞争底物）、环孢素 A（mPTP 阻断剂）和依达拉奉（自由基清除剂）作为阳性对照相似。然而，pAD/DDAH II-shRNA 腺病毒的添加逆转了 Lut 的上述有益作用。总之，Lut 可以通过 ROS/ADMA/DDAH II/eNOS/NO 通路保护 HUVEC 免受铁过载损伤。线粒体是 Lut 保护作用的靶细胞器。
