Department of Biotechnology, University of Kaiserslautern, Kaiserslautern, Germany.
Mol Nutr Food Res. 2009 Oct;53(10):1263-80. doi: 10.1002/mnfr.200800575.
Apples (Malus spp., Rosaceae) and products thereof contain high amounts of polyphenols which show diverse biological activities and may contribute to beneficial health effects, like protecting the intestine against inflammation initiated by chronic inflammatory bowel diseases (IBD). IBD are characterized by an excessive release of several proinflammatory cytokines and chemokines by different cell types which results consequently in an increased inflammatory response. In the present study we investigated the preventive effectiveness of polyphenolic juice extracts and single major constituents on inflammatory gene expression in immunorelevant human cell lines (DLD-1, T84, MonoMac6, Jurkat) induced with specific stimuli. Besides the influence on proinflammatory gene expression, the effect on NF-kappaB-, IP-10-, IL-8-promoter-, STAT1-dependent signal transduction, and the relative protein levels of multiple released cytokines and chemokines were studied. DNA microarray analysis of several genes known to be strongly regulated during gastrointestinal inflammation, combined with quantitative real-time PCR (qRT-PCR) revealed that the apple juice extract AE04 (100-200 microg/mL) significantly inhibited the expression of NF-kappaB regulated proinflammatory genes (TNF-alpha, IL-1beta, CXCL9, CXCL10), inflammatory relevant enzymes (COX-2, CYP3A4), and transcription factors (STAT1, IRF1) in LPS/IFN-gamma stimulated MonoMac6 cells without significant effects on the expression of house-keeping genes. A screening of some major compounds of AE04 revealed that the flavan-3-ol dimer procyanidin B(2 )is mainly responsible for the anti-inflammatory activity of AE04. Furthermore, the dihydrochalcone aglycone phloretin and the dimeric flavan-3-ol procyanidin B(1 )significantly inhibited proinflammatory gene expression and repressed NF-kappaB-, IP-10-, IL-8-promoter-, and STAT1-dependent signal transduction in a dose-dependent manner. The influence on proinflammatory gene expression by the applied polyphenols thereby strongly correlated with the increased protein levels investigated by human cytokine array studies. In summary, we evaluated selected compounds responsible for the anti-inflammatory activity of AE04. In particular, procyanidin B(1), procyanidin B(2), and phloretin revealed anti-inflammatory activities in vitro and therefore may serve as transcription-based inhibitors of proinflammatory gene expression.
苹果（Malus spp.，蔷薇科）及其产品含有大量的多酚，具有多种生物活性，可能有助于对健康有益的影响，如保护肠道免受慢性炎症性肠病（IBD）引起的炎症。IBD 的特征是不同细胞类型过度释放几种促炎细胞因子和趋化因子，导致炎症反应增加。在本研究中，我们研究了多酚果汁提取物和单一主要成分对特定刺激诱导的无免疫相关性人细胞系（DLD-1、T84、MonoMac6、Jurkat）中炎症基因表达的预防作用。除了对促炎基因表达的影响外，还研究了 NF-kappaB、IP-10、IL-8 启动子、STAT1 依赖性信号转导以及多种释放细胞因子和趋化因子的相对蛋白水平的影响。对已知在胃肠道炎症期间强烈调节的几种基因进行 DNA 微阵列分析，并结合定量实时 PCR（qRT-PCR），发现苹果汁提取物 AE04（100-200μg/mL）可显著抑制 LPS/IFN-γ刺激的 MonoMac6 细胞中 NF-kappaB 调节的促炎基因（TNF-α、IL-1β、CXCL9、CXCL10）、炎症相关酶（COX-2、CYP3A4）和转录因子（STAT1、IRF1）的表达，而对管家基因的表达没有显著影响。AE04 中一些主要化合物的筛选表明，黄烷-3-醇二聚体原花青素 B2 主要负责 AE04 的抗炎活性。此外，二氢查耳酮糖苷元根皮素和二聚黄烷-3-醇原花青素 B1 以剂量依赖的方式显著抑制促炎基因表达，并抑制 NF-kappaB、IP-10、IL-8 启动子和 STAT1 依赖性信号转导。所应用的多酚对促炎基因表达的影响与通过人类细胞因子阵列研究调查的增加的蛋白质水平强烈相关。总之，我们评估了负责 AE04 抗炎活性的选定化合物。特别是原花青素 B1、原花青素 B2 和根皮素在体外具有抗炎活性，因此可作为促炎基因表达的基于转录的抑制剂。
