Kim Min-Hye, Kim Jin Nam, Han Sung Nim, Kim Hye-Kyeong
Department of Food Science and Nutrition, The Catholic University of Korea , Bucheon , Republic of Korea and.
Immunopharmacol Immunotoxicol. 2015 Jun;37(3):228-35. doi: 10.3109/08923973.2015.1021355. Epub 2015 Mar 10.
Psidium guajava (guava) leaves have been frequently used for the treatment of rheumatism, fever, arthritis and other inflammatory conditions. The purpose of this study was to identify major anti-inflammatory compounds from guava leaf extract. The methanol extract and its hexane-, dichloromethane-, ethylacetate-, n-butanol- and water-soluble phases derived from guava leaves were evaluated to determine their inhibitory activity on nitric oxide (NO) production by RAW 264.7 cells stimulated with lipopolysaccharide (LPS). The methanol extract decreased NO production in a dose-dependent manner without cytotoxicity at a concentration range of 0-100 μg/mL. The n-butanol soluble phase was the most potent among the five soluble phases. Four compounds were isolated by reversed-phase HPLC from the n-butanol soluble phase and identified to be avicularin, guaijaverin, leucocyanidin and ursolic acid by their NMR spectra. Among these compounds, ursolic acid inhibited LPS-induced NO production in a dose-dependent manner without cytotoxity at a concentration range of 1-10 µM, but the other three compounds had no effect. Ursolic acid also inhibited LPS-induced prostaglandin E2 production. A western blot analysis showed that ursolic acid decreased the LPS-stimulated inducible nitric oxide synthase and cyclooxygenase protein levels. In addition, ursolic acid suppressed the production of intracellular reactive oxygen species in LPS-stimulated RAW 264.7 cells, as measured by flow cytometry. Taken together, these results identified ursolic acid as a major anti-inflammatory compound in guava leaves.
番石榴叶常用于治疗风湿、发热、关节炎及其他炎症性疾病。本研究旨在从番石榴叶提取物中鉴定出主要的抗炎化合物。对番石榴叶的甲醇提取物及其正己烷、二氯甲烷、乙酸乙酯、正丁醇和水溶性相进行评估，以确定它们对脂多糖（LPS）刺激的RAW 264.7细胞产生一氧化氮（NO）的抑制活性。甲醇提取物在0 - 100μg/mL浓度范围内呈剂量依赖性降低NO产生且无细胞毒性。正丁醇可溶相在五个可溶相中活性最强。通过反相高效液相色谱从正丁醇可溶相中分离出四种化合物，经核磁共振光谱鉴定为杨梅苷、番石榴苷、无色花青素和熊果酸。在这些化合物中，熊果酸在1 - 10μM浓度范围内呈剂量依赖性抑制LPS诱导的NO产生且无细胞毒性，但其他三种化合物无此作用。熊果酸还抑制LPS诱导的前列腺素E2产生。蛋白质印迹分析表明，熊果酸降低了LPS刺激的诱导型一氧化氮合酶和环氧化酶蛋白水平。此外，通过流式细胞术检测，熊果酸抑制了LPS刺激的RAW 264.7细胞内活性氧的产生。综上所述，这些结果确定熊果酸是番石榴叶中的主要抗炎化合物。
