Mu Fei, Zhao Jiaxin, Zhao Meina, Lin Rui, Liu Kedi, Zhao Shi, Tao Xingru, Li Weihong, Dai Qi, Xi Miaomiao, Tang Haifeng, Wang Jingwen
Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
Department of Chinese Materia Medica and Natural Medicines, Fourth Military Medical University, Xi'an 710032, China.
J Pharm Pharmacol. 2023 Dec 8;75(12):1496-1508. doi: 10.1093/jpp/rgad093.
To explore the effect of extract of Styrax (ES) on myocardial ischemic injury and its molecular mechanism, indirectly providing a theoretical basis for the development of ES.
In order to assess the impact of ES treatment on ischemic heart disease, both a left anterior descending ligation-induced myocardial infarction (MI) model and an ischemia/hypoxia (I/H)-induced H9c2 cell injury model have been constructed. Specifically, Sprague-Dawley rats were randomly assigned to the following groups (n = 8) and administered intragastrically once a day for seven consecutive days: Sham group, MI group, ES-L (0.2 g/kg) group, ES-M (0.4 g/kg) group, ES-H (0.8 g/kg) group, and trimetazidine (TMZ, 0.02 g/kg) group. The cardiac functions and biochemical assessment of rats were detected. Then, we validated experimentally the targets and mechanism of ES on these pathological processes in I/H-induced H9c2 cell injury model.
These results showed that different doses of ES (0.2 g/kg, 0.4 g/kg, 0.8 g/kg, intragastric) significantly improved myocardial structure and function when compared to the MI group. The results of 2,3,5-triphenyltetrazolium chloride (TTC), hematoxylin-eosin, and masson staining indicated that ES could significantly reduce infarct size, inhibit myocardium apoptosis, and decrease myocardial fibrosis. Moreover, ES distinctly suppressed the serum levels of lactate dehydrogenase (LDH), cardiac troponin T (cTnT), and creatine kinase-MB (CK-MB), alleviated myocardial mitochondrial morphology, and stimulated adenosine triphosphate (ATP) production, increased the level of succinate dehydrogenase (SDH), complex I and complex V activity. Different doses of ES (5 μg/ml, 10 μg/ml, 20 μg/ml) also improved cardiomyocyte morphology and decreased the apoptosis rate in H9c2 cells that had been exposed to I/H. Furthermore, the results of western blotting and qRT-PCR indicated that ES promoted the expression of proteins and mRNA related to energy metabolism, including phosphorylated adenosine monophosphate activated protein kinase (p-AMPK), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PCG-1α), nuclear respiratory factor 1, and mitochondrial transcription factor A (TFAM). Mechanically, after the administration of Compound C (dorsomorphin), an AMPK inhibitor, these effects of myocardial protection produced by ES were reversed.
Collectively, these results demonstrated that ES could improve myocardial mitochondrial function and reduce ischemic injury by activating AMPK/PCG-1α signaling pathway, while indicating its potential advantages as a dietary supplement.
探讨苏合香提取物（ES）对心肌缺血损伤的影响及其分子机制，为ES的开发间接提供理论依据。
为评估ES治疗对缺血性心脏病的影响，构建了左前降支结扎诱导的心肌梗死（MI）模型和缺血/缺氧（I/H）诱导的H9c2细胞损伤模型。具体而言，将Sprague-Dawley大鼠随机分为以下几组（n = 8），连续7天每天灌胃一次：假手术组、MI组、ES-L（0.2 g/kg）组、ES-M（0.4 g/kg）组、ES-H（0.8 g/kg）组和曲美他嗪（TMZ，0.02 g/kg）组。检测大鼠的心功能和生化指标。然后，我们在I/H诱导的H9c2细胞损伤模型中通过实验验证了ES对这些病理过程的作用靶点和机制。
这些结果表明，与MI组相比，不同剂量的ES（0.2 g/kg、0.4 g/kg、0.8 g/kg，灌胃）显著改善了心肌结构和功能。2,3,5-氯化三苯基四氮唑（TTC）、苏木精-伊红和Masson染色结果表明，ES可显著减小梗死面积，抑制心肌细胞凋亡，并减少心肌纤维化。此外，ES明显抑制血清乳酸脱氢酶（LDH）、心肌肌钙蛋白T（cTnT）和肌酸激酶同工酶MB（CK-MB）水平，减轻心肌线粒体形态改变，刺激三磷酸腺苷（ATP）生成，提高琥珀酸脱氢酶（SDH）水平、复合体I和复合体V活性。不同剂量的ES（5 μg/ml、10 μg/ml、20 μg/ml）也改善了I/H处理后的H9c2细胞的心肌细胞形态并降低凋亡率。此外，蛋白质免疫印迹和qRT-PCR结果表明，ES促进了与能量代谢相关的蛋白质和mRNA的表达，包括磷酸化的腺苷酸活化蛋白激酶（p-AMPK）、过氧化物酶体增殖物激活受体γ共激活因子1α（PCG-1α）、核呼吸因子1和线粒体转录因子A（TFAM）。机制上，给予AMPK抑制剂Compound C（ Dorsomorphin）后，ES产生的这些心肌保护作用被逆转。
总体而言，这些结果表明ES可通过激活AMPK/PCG-１α信号通路改善心肌线粒体功能并减轻缺血损伤，同时表明其作为膳食补充剂的潜在优势。
