Aslan M, Kıraç E, Yılmaz Ö, Ünal B, Konuk E K, Özcan F, Tuzcu H
1 Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
2 Human Gene and Cell Therapy Center, Akdeniz University Faculty of Medicine, Antalya, Turkey.
Hum Exp Toxicol. 2018 Aug;37(8):803-816. doi: 10.1177/0960327117734621. Epub 2017 Oct 13.
The aim of this study was to evaluate hepatic polyunsaturated fatty acids (PUFAs) and inflammatory response in an animal and cell model of endoplasmic reticulum (ER) stress. Rats were divided into control, tunicamycin (TM)-treated, and TM + tauroursodeoxycholic acid (TUDCA)-treated groups. Hepatic ER stress was induced by TM and the ER stress inhibitor TUDCA was injected 30 min before induction of ER stress. Liver THLE-3 cells were treated with TM and TUDCA was administered in advance to decrease cytotoxic effects. Necroinflammation was evaluated in liver sections, while cell viability was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay kit. ER stress was confirmed by immunofluorescence and Western blot analysis of C/EBP-homologous protein and 78-kDa glucose-regulated protein. Arachidonic acid (C20:4n-6), dihomo-γ-linolenic acid (C20:3n-6), eicosapentaenoic acid (C20:5n-3), and docosahexaenoic acid (C22:6n-3) in liver tissue and THLE-3 cells were determined by liquid chromatography tandem mass spectrometry (LC-MS/MS). Phospholipase A2 (PLA2), cyclooxygenase (COX), and prostaglandin E2 (PGE2) were measured in tissue and cell samples. Hepatic ER stress was accomplished by TM and was alleviated by TUDCA. TM treatment significantly decreased PUFAs in both liver and THLE-3 cells compared to controls. PLA2, COX, and PGE2 levels were significantly increased in TM-treated rats and THLE-3 cells compared to controls. TUDCA leads to a partial restoration of liver PUFA levels and decreased PLA2, COX, and PGE2. This study reports decreased PUFA levels in ER stress and supports the use of omega-3 fatty acids in liver diseases demonstrating ER stress.
本研究旨在评估内质网（ER）应激动物模型和细胞模型中的肝脏多不饱和脂肪酸（PUFA）及炎症反应。将大鼠分为对照组、衣霉素（TM）处理组和TM + 牛磺熊去氧胆酸（TUDCA）处理组。通过TM诱导肝脏ER应激，并在诱导ER应激前30分钟注射ER应激抑制剂TUDCA。用TM处理肝脏THLE-3细胞，并预先给予TUDCA以降低细胞毒性作用。在肝脏切片中评估坏死性炎症，同时使用3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐检测试剂盒测定细胞活力。通过免疫荧光以及对C/EBP同源蛋白和78 kDa葡萄糖调节蛋白进行蛋白质印迹分析来确认ER应激。采用液相色谱串联质谱法（LC-MS/MS）测定肝组织和THLE-3细胞中的花生四烯酸（C20:4n-6）、二高-γ-亚麻酸（C20:3n-6）、二十碳五烯酸（C20:5n-3）和二十二碳六烯酸（C22:6n-3）。测定组织和细胞样品中的磷脂酶A2（PLA2）、环氧化酶（COX）和前列腺素E2（PGE2）。TM可诱导肝脏ER应激，而TUDCA可减轻该应激。与对照组相比，TM处理显著降低了肝脏和THLE-3细胞中的PUFA。与对照组相比，TM处理的大鼠和THLE-3细胞中PLA2、COX和PGE2水平显著升高。TUDCA可使肝脏PUFA水平部分恢复，并降低PLA2、COX和PGE2。本研究报告了ER应激时PUFA水平降低，并支持在表现出ER应激的肝脏疾病中使用ω-3脂肪酸。
