Department of Food & Nutrition Education, Graduate School of Education, Soonchunhyang University, Asan, Chungnam 336-745, Korea.
Department of Obstetrics and Gynecology, Soonchunhyang University Cheonan Hospital, Soonchunhyang-6-gil 31, Dongnam-gu, Cheonan 330-721, Korea.
Nutr Res Pract. 2014 Oct;8(5):516-20. doi: 10.4162/nrp.2014.8.5.516. Epub 2014 Jun 30.
BACKGROUND/OBJECTIVES: Carnosic acid (CA), found in rosemary (Rosemarinus officinalis) leaves, is known to exhibit anti-obesity and anti-inflammatory activities. However, whether its anti-inflammatory potency can contribute to the amelioration of obesity has not been elucidated. The aim of the current study was to investigate the effect of CA on Toll-like receptor 4 (TLR4) pathways in the presence of lipopolysaccharide (LPS) in 3T3-L1 adipocytes.
MATERIALS/METHODS: 3T3-L1 adipocytes were treated with CA (0-20 µM) for 1 h, followed by treatment with LPS for 30 min; mRNA expression of adipokines and protein expression of TLR4-related molecules were then measured.
LPS-stimulated 3T3-L1 adipocytes showed elevated mRNA expression of tumor necrosis factor (TNF)-α, interleukin-6, and monocyte chemoattractant protein-1, and CA significantly inhibited the expression of these adipokine genes. LPS-induced up regulation of TLR4, myeloid differentiation factor 88, TNF receptor-associated factor 6, and nuclear factor-κB, as well as phosphorylated extracellular receptor-activated kinase were also suppressed by pre-treatment of 3T3-L1 adipocytes with CA.
Results of this study suggest that CA directly inhibits TLR4-MyD88-dependent signaling pathways and decreases the inflammatory response in adipocytes.
背景/目的：迷迭香（Rosemarinus officinalis）叶中的迷迭香酸（CA）具有抗肥胖和抗炎活性。然而，其抗炎效力是否有助于改善肥胖尚未阐明。本研究旨在探讨 CA 在 3T3-L1 脂肪细胞中存在脂多糖（LPS）时对 Toll 样受体 4（TLR4）途径的影响。
材料/方法：用 CA（0-20 μM）处理 3T3-L1 脂肪细胞 1 小时，然后用 LPS 处理 30 分钟；然后测量脂肪因子的 mRNA 表达和 TLR4 相关分子的蛋白表达。
LPS 刺激的 3T3-L1 脂肪细胞表现出肿瘤坏死因子（TNF）-α、白细胞介素-6 和单核细胞趋化蛋白-1 的 mRNA 表达升高，CA 显著抑制这些脂肪因子基因的表达。CA 预处理还抑制了 LPS 诱导的 TLR4、髓样分化因子 88、TNF 受体相关因子 6 和核因子-κB 的上调，以及细胞外受体激活激酶的磷酸化。
本研究结果表明，CA 直接抑制 TLR4-MyD88 依赖性信号通路，并降低脂肪细胞的炎症反应。
