Wakabayashi I, Yasui K
Department of Hygiene and Preventive Medicine, School of Medicine, Yamagata University, Iida-Nishi 2-2-2, 990-9585, Yamagata, Japan.
Eur J Pharmacol. 2000 Oct 20;406(3):477-81. doi: 10.1016/s0014-2999(00)00695-6.
Effects of 5,7-dihydroxy-8-methoxyflavone (wogonin) on cyclooxygenase-2 (COX-2)-mediated prostaglandin E(2) production in macrophages were investigated. Stimulation with lipopolysaccharide (LPS; 1 microg/ml) greatly increased prostaglandin E(2) production in RAW 264.7 murine macrophages. The stimulated prostaglandin E(2) production was abolished in the presence of indomethacin (1 microM) or cycloheximide (2 microM), suggesting that the increased production of prostaglandin E(2) by LPS reflects the inducible synthesis of prostaglandin E(2) by COX-2. Wogonin (0.1-50 microM) concentration-dependently inhibited inducible prostaglandin E(2) production. Wogonin at concentrations as low as 0.5 microM directly attenuated enzymatic activity of COX-2. The protein expression of COX-2 was depressed by wogonin at concentrations of 10 microM and more. These results suggest that wogonin decreases inducible prostaglandin E(2) production in macrophages by inhibiting both COX-2 activity and COX-2 expression. The former action requires much lower doses of wogonin. These wogonin actions may explain, in part, its anti-inflammatory action.
研究了5,7 - 二羟基 - 8 - 甲氧基黄酮（汉黄芩素）对巨噬细胞中环氧合酶 - 2（COX - 2）介导的前列腺素E2生成的影响。用脂多糖（LPS；1微克/毫升）刺激可显著增加RAW 264.7小鼠巨噬细胞中前列腺素E2的生成。在吲哚美辛（1微摩尔）或环己酰亚胺（2微摩尔）存在的情况下，刺激引起的前列腺素E2生成被消除，这表明LPS导致的前列腺素E2生成增加反映了COX - 2诱导的前列腺素E2合成。汉黄芩素（0.1 - 50微摩尔）呈浓度依赖性抑制诱导性前列腺素E2的生成。低至0.5微摩尔浓度的汉黄芩素可直接减弱COX - 2的酶活性。浓度为10微摩尔及以上的汉黄芩素可降低COX - 2的蛋白表达。这些结果表明，汉黄芩素通过抑制COX - 2活性和COX - 2表达来减少巨噬细胞中诱导性前列腺素E2的生成。前一种作用所需的汉黄芩素剂量要低得多。这些汉黄芩素的作用可能部分解释了其抗炎作用。
