Department of Nutrition, Faculty of Medicine, University of Oslo, 0316 Oslo, Norway.
Free Radic Biol Med. 2010 May 1;48(9):1218-27. doi: 10.1016/j.freeradbiomed.2010.02.005. Epub 2010 Feb 20.
Coffee, one of the most popular beverages worldwide, is a major contributor of phytochemicals in the diet and contributes more than 50% of dietary antioxidants in many countries. A moderate intake of coffee has been linked to reduced risk of chronic diseases. Furthermore, experimental studies demonstrate bioactivity of coffee or coffee compounds in inflammation and oxidative stress, two major, related biological processes. We show that the degree of roasting correlates with the efficiency of dampening inflammation-induced NF-kappaB activity and inducing antioxidant defense through Nrf2/EpRE activity. Extracts of dark-roasted coffee inhibit NF-kappaB activity by more than 80% and induce EpRE activity more than 25-fold in vitro. In transgenic NF-kappaB-luciferase mice, a single dose of dark-roasted coffee extract per os inhibits NF-kappaB activation by 63% in the whole mouse, with the liver being the main target, with a 68% reduction in activity. In transgenic EpRE-luciferase mice, the extract of coffee increased overall EpRE activity by 30%, again with the liver as the main contributor, with a 2.7-fold increase. Our results demonstrate that dark-roasted coffee dampens a crucial mechanism in inflammation and induces a pivotal mechanism in oxidative stress defense.
咖啡是全球最受欢迎的饮品之一，是饮食中植物化学物质的主要来源，在许多国家，咖啡提供的膳食抗氧化剂超过 50%。适量饮用咖啡与降低慢性病风险有关。此外，实验研究表明，咖啡或咖啡化合物具有抗炎和氧化应激的生物活性，这是两个主要的相关生物学过程。我们发现，烘焙程度与抑制炎症诱导的 NF-κB 活性和通过 Nrf2/EpRE 活性诱导抗氧化防御的效率相关。深度烘焙咖啡提取物在体外可使 NF-κB 活性抑制超过 80%，并使 EpRE 活性诱导超过 25 倍。在 NF-κB-荧光素酶转基因小鼠中，单次口服深度烘焙咖啡提取物可使整个小鼠的 NF-κB 激活抑制 63%，肝脏是主要靶点，活性降低 68%。在 EpRE-荧光素酶转基因小鼠中，咖啡提取物使整体 EpRE 活性增加 30%，肝脏仍是主要贡献者，活性增加 2.7 倍。我们的结果表明，深度烘焙咖啡可抑制炎症中的关键机制，并诱导氧化应激防御中的关键机制。
