Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, 1-1, Jen-Ai Road, Taipei, 100, Taiwan.
Inflamm Res. 2012 Feb;61(2):151-60. doi: 10.1007/s00011-011-0399-1. Epub 2011 Nov 18.
A 1:1 ratio of fatty acid (FA)-albumin complex was chosen to mimic physiological conditions, and the effects of FA-bovine serum albumin (BSA) complexes were tested in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.
Nitric oxide (NO) and various proteins/factors in RAW264.7 cells were quantified as follows: NO by the Griess assay; prostaglandin (PG) E(2), interleukin (IL)-6 and tumor necrosis factor (TNF)-α by ELISA; inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 by Western blotting; and NF-κB and CD14/TLR4 by Western blotting or flow cytometry.
BSA- or FA-BSA-treated RAW264.7 cells without LPS stimulation did not show any significant changes in NO or the tested proteins/factors and thus did not have any pro-inflammatory responses. Pre-treatment with unsaturated FA-BSA complexes significantly decreased the production of LPS-induced NO, PGE(2), IL-6 and TNF-α, the expression of iNOS, COX-2 and CD14, IκB degradation and NF-κB translocation. On the contrary, pre-treatment with saturated FA-BSA complexes enhanced these LPS-induced pro-inflammatory factors and the subsequent responses.
We concluded that unsaturated FA-BSA complexes, but not saturated FA-BSA complexes, exert an inhibitory effect on the LPS-induced pro-inflammatory response and that this effect may be partially mediated through suppression of the NF-κB signaling pathway. We suggest that an increase of unsaturated FA-BSA complexes may enhance the host's defense against bacterial infection.
选择脂肪酸（FA）-白蛋白复合物的 1:1 比例来模拟生理条件，并测试 FA-牛血清白蛋白（BSA）复合物在脂多糖（LPS）刺激的 RAW264.7 巨噬细胞中的作用。
通过格里塞斯测定法来定量 RAW264.7 细胞中的一氧化氮（NO）和各种蛋白质/因子；通过 ELISA 来定量前列腺素（PG）E(2)、白细胞介素（IL）-6 和肿瘤坏死因子（TNF）-α；通过 Western 印迹来定量诱导型一氧化氮合酶（iNOS）和环氧化酶（COX）-2；通过 Western 印迹或流式细胞术来定量 NF-κB 和 CD14/TLR4。
未经 LPS 刺激的 BSA 或 FA-BSA 处理的 RAW264.7 细胞在 NO 或测试的蛋白质/因子方面没有显示出任何显著变化，因此没有产生任何促炎反应。预先用不饱和 FA-BSA 复合物处理可显著降低 LPS 诱导的 NO、PGE(2)、IL-6 和 TNF-α的产生，降低 iNOS、COX-2 和 CD14 的表达，抑制 IκB 降解和 NF-κB 易位。相反，预先用饱和 FA-BSA 复合物处理会增强这些 LPS 诱导的促炎因子及其后续反应。
我们得出结论，不饱和 FA-BSA 复合物而非饱和 FA-BSA 复合物对 LPS 诱导的促炎反应具有抑制作用，这种作用可能部分通过抑制 NF-κB 信号通路来介导。我们建议，增加不饱和 FA-BSA 复合物可能会增强宿主对细菌感染的防御能力。
