Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Department of Obstetrics and Gynaecology, the Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Front Endocrinol (Lausanne). 2022 Jul 15;13:899271. doi: 10.3389/fendo.2022.899271. eCollection 2022.
Green tea extract (GTE) alleviated ocular inflammations in endotoxin-induced uveitis (EIU) rat model induced by lipopolysaccharide (LPS) but the underlying mechanism is unclear.
To investigate the systematic and local mechanisms of the alleviation by untargeted metabolomics using liquid chromatography-tandem mass spectrometry.
Sprague-Dawley rats were divided into control group, LPS treatment group, and LPS treatment group treated with GTE two hours after LPS injection. The eyes were monitored by slip lamp and electroretinography examination after 24 hours. The plasma and retina were collected for metabolomics analysis.
In LPS treated rats, the iris showed hyperemia. Plasma prostaglandins, arachidonic acids, corticosteroid metabolites, and bile acid metabolites increased. In the retina, histamine antagonists, corticosteroids, membrane phospholipids, free antioxidants, and sugars also increased but fatty acid metabolites, N-acetylglucosamine-6-sulphate, pyrocatechol, and adipic acid decreased. After GTE treatment, the a- and b- waves of electroretinography increased by 13%. Plasma phosphorylcholine lipids increased but plasma prostaglandin E1, cholanic metabolites, and glutarylglycine decreased. In the retina, tetranor-PGAM, pantothenic derivatives, 2-ethylacylcarinitine, and kynuramine levels decreased but anti-oxidative seleno-peptide level increased. Only phospholipids, fatty acids, and arachidonic acid metabolites in plasma and in the retina had significant correlation (p < 0.05, r > 0.4 or r < -0.4).
The results showed GTE indirectly induced systemic phosphorylcholine lipids to suppress inflammatory responses, hepatic damage, and respiratory mitochondrial stress in EIU rats induced by LPS. Phospholipids may be a therapeutic target of GTE for anterior chamber inflammation.
绿茶提取物（GTE）可减轻脂多糖（LPS）诱导的内毒素性葡萄膜炎（EIU）大鼠模型中的眼内炎症，但作用机制尚不清楚。
使用液相色谱-串联质谱法进行非靶向代谢组学研究，探讨其缓解作用的系统和局部机制。
将 Sprague-Dawley 大鼠分为对照组、LPS 处理组和 LPS 处理组，LPS 处理组在 LPS 注射后 2 小时给予 GTE 治疗。24 小时后通过裂隙灯和视网膜电流图检查观察眼睛情况。收集血浆和视网膜进行代谢组学分析。
在 LPS 处理的大鼠中，虹膜出现充血。血浆前列腺素、花生四烯酸、皮质类固醇代谢物和胆酸代谢物增加。在视网膜中，组胺拮抗剂、皮质类固醇、膜磷脂、游离抗氧化剂和糖也增加，但脂肪酸代谢物、N-乙酰氨基葡萄糖-6-硫酸盐、邻苯二酚和己二酸减少。GTE 治疗后，视网膜电图的 a-和 b-波增加了 13%。血浆磷酸胆碱脂质增加，但血浆前列腺素 E1、胆烷代谢物和谷氨酰甘氨酸减少。在视网膜中，四氢-N-甲基戊二酰氨、泛酸衍生物、2-乙基酰基卡尼汀和犬尿氨酸水平降低，但抗氧化硒肽水平升高。仅血浆和视网膜中的磷脂、脂肪酸和花生四烯酸代谢物具有显著相关性（p<0.05，r>0.4 或 r<-0.4）。
结果表明，GTE 间接诱导系统磷酸胆碱脂质，抑制 LPS 诱导的 EIU 大鼠的炎症反应、肝损伤和呼吸线粒体应激。磷脂可能是 GTE 治疗前房炎症的治疗靶点。
