Department of Surgery and Alvin J Siteman Cancer Center, Washington University in St. Louis, 660 South Euclid Avenue, Campus Box 8109, St Louis, Missouri 63110, USA.
Pharm Res. 2010 Jun;27(6):1066-71. doi: 10.1007/s11095-010-0056-3. Epub 2010 Jan 29.
To compare the chemopreventive efficacy of Polyphenon E (Poly E), (-)-epigallocatechin-3-gallate (EGCG) and Polyphenon E without EGCG (Poly E-EGCG) on the development of benzo(a)pyrene (B(a)P)-induced lung tumors in A/J mice.
Female A/J mice were given a single intraperitoneal injection of B(a)P (100 mg/kg body weight). One week after B(a)P injection, animals received AIN-76A purified powder diet containing 0.975% (wt/wt) EGCG, 0.525% (wt/wt) Poly E-EGCG or 1.5% (wt/wt) Poly E for 24 weeks or control diet with no additives.
Poly E treatment significantly decreased tumor multiplicity by 52% and tumor load by 64%, while EGCG and Poly E-EGCG did not significantly inhibit lung tumor multiplicity. EGCG was more stable in a complex mixture (Poly E) than as a pure compound.
EGCG was ineffective when administered by diet likely due to its instability. Thus, EGCG's efficacy on mice lung tumorigenesis requires the presence of other tea catechins.
比较多酚 E(Poly E)、(-)-表没食子儿茶素-3-没食子酸酯(EGCG)和不含 EGCG 的多酚 E(Poly E-EGCG)对 A/J 小鼠苯并(a)芘(B(a)P)诱导肺肿瘤发展的化学预防功效。
雌性 A/J 小鼠单次腹腔注射 B(a)P(100mg/kg 体重)。B(a)P 注射后 1 周,动物接受含 0.975%(wt/wt)EGCG、0.525%(wt/wt)Poly E-EGCG 或 1.5%(wt/wt)Poly E 的 AIN-76A 纯化粉末饮食,或不含添加剂的对照饮食,共 24 周。
Poly E 处理显著降低了 52%的肿瘤多发性和 64%的肿瘤负荷,而 EGCG 和 Poly E-EGCG 并未显著抑制肺肿瘤多发性。EGCG 在复杂混合物(Poly E)中比作为纯化合物更稳定。
EGCG 通过饮食给药时无效,可能是由于其不稳定性。因此,EGCG 对小鼠肺癌发生的功效需要其他茶儿茶素的存在。