Miyamoto Yohei, Sano Mariko, Haylor John L, El Nahas A Meguid
J Toxicol Sci. 2008 Aug;33(3):367-70. doi: 10.2131/jts.33.367.
(-)-Epigallocatechin 3-O-gallate (EGCG), a major catechin in green tea, suppresses renal failure in animals, and inhibits the growth of mesangial cells and opossum kidney proximal tubular cells. In addition, gallic acid, a structural constituent of this catechin, induces apoptosis in tumor cell lines. However, the effects of catechins on renal fibroblastic cells have not been investigated. In this experiment, the growth of normal rat kidney interstitial fibroblast (NRK-49F) cells was significantly inhibited by EGCG at concentrations higher than 6.25 microM, and almost completely inhibited at concentrations over 200 microM. The numbers of in situ end-labeled (ISEL) cells in cultures treated with EGCG at 6.25 to 200 microM increased dose-dependently. Furthermore, exposure to 6.25 to 50 microM EGCG for 24 hr led to a significant increase in caspase-3 activity compared to the control. These results suggest that EGCG induces apoptosis in NRK-49F cells.
（-）-表没食子儿茶素-3-没食子酸酯（EGCG）是绿茶中的主要儿茶素，可抑制动物肾衰竭，并抑制系膜细胞和负鼠肾近端小管细胞的生长。此外，这种儿茶素的结构成分没食子酸可诱导肿瘤细胞系凋亡。然而，儿茶素对肾成纤维细胞的作用尚未得到研究。在本实验中，浓度高于6.25微摩尔/升的EGCG可显著抑制正常大鼠肾间质成纤维细胞（NRK-49F）的生长，浓度超过200微摩尔/升时几乎完全抑制。用6.25至200微摩尔/升的EGCG处理的培养物中，原位末端标记（ISEL）细胞数量呈剂量依赖性增加。此外，与对照组相比，暴露于6.25至50微摩尔/升的EGCG 24小时导致caspase-3活性显著增加。这些结果表明EGCG可诱导NRK-49F细胞凋亡。
