Different Curcuminoids Inhibit T-Lymphocyte Proliferation Independently of Their Radical Scavenging Activities
作者:Michael Deters、Heiko Knochenwefel、Daniel Lindhorst、Therese Koal、Hartmut H. Meyer、Wolfram Hänsel、Klaus Resch、Volkhard Kaever
DOI:10.1007/s11095-008-9579-2
日期:2008.8
We investigated the inhibitory effects of curcumin, curcumin derivatives and degradation products on OKT3-induced human peripheral blood mononuclear cell (PBMC) proliferation and the role of their radical scavenging activity. OKT3-induced human PBMC proliferation was determined by measuring 3H-thymidine incorporation. Radical scavenging activity was evaluated by using an in vitro DPPH assay. OKT3-induced PBMC proliferation was inhibited by curcumin, isocurcumin, bisdesmethoxy-, diacetyl-, tetrahydro-, hexahydro-, and octahydrocurcumin as well as by vanillin, ferulic acid, and dihydroferulic acid with IC50-values of 2.8, 2.8, 6.4, 1.0, 25, 38, 82, 729, 457, and >1,000 μM, respectively. The investigated substances with the strongest effect on radical scavenging were tetrahydro-, hexahydro-, and octahydrocurcumin with IC50 values of 10.0, 11.7, and 12.3 μM, respectively. IC50-values of dihydroferulic acid, ferulic acid, and curcumin were 19.5, 37, and 40 μM. The substances with the lowest radical scavenging activities were vanillin, isocurcumin, diacetylcurcumin, and bisdesmethoxycurcumin with IC50 values higher than 100 μM each. Curcuminoid-induced inhibition of OKT3-induced PBMC proliferation depends on the number of carbon atoms and double bonds of the 1,6-heptadiene-3,5-dione structure as well as on the phenolic ring substitutes of the curcuminoids but is not correlated to their respective radical scavenging activity.
我们研究了姜黄素、姜黄素衍生物和降解产物对OKT3诱导的人外周血单个核细胞(PBMC)增殖的抑制作用及其自由基清除活性所扮演的角色。通过测定3H-胸苷掺入量来确定OKT3诱导的人PBMC增殖。使用体外DPPH assay评估自由基清除活性。OKT3诱导的PBMC增殖被姜黄素、异姜黄素、双去甲氧基姜黄素、二乙酰姜黄素、四氢姜黄素、六氢姜黄素、八氢姜黄素、香兰素、阿魏酸和二氢阿魏酸以IC50值分别为2.8、2.8、6.4、1.0、25、38、82、729、457和>1000 μM抑制。研究中自由基清除效果最强的物质是四氢姜黄素、六氢姜黄素和八氢姜黄素,IC50值分别为10.0、11.7和12.3 μM。二氢阿魏酸、阿魏酸和姜黄素的IC50值分别为19.5、37和40 μM。自由基清除活性最低的物质是香兰素、异姜黄素、二乙酰姜黄素和双去甲氧基姜黄素,其IC50值均高于100 μM。姜黄素类化合物诱导的OKT3诱导PBMC增殖抑制依赖于1,6-庚二烯-3,5-二酮结构中的碳原子数目和双键,以及姜黄素类化合物的酚环取代基,但与其各自的自由基清除活性无相关性。