FBS or BSA Inhibits EGCG Induced Cell Death through Covalent Binding and the Reduction of Intracellular ROS Production.
Previously we have shown that (-)-epigallocatechin gallate (EGCG) can induce nonapoptotic cell death in human hepatoma HepG2cells only under serum-free condition. However, the underlying mechanism for serum in determining the cell fate remains to be answered. The effects of fetal bovine serum (FBS) and its major component bovine serum albumin (BSA) on EGCG-induced cell death were investigated in this study. It was found that BSA, just like FBS, can protect cells from EGCG-induced cell death in a dose-dependent manner. Detailed analysis revealed that both FBS and BSA inhibited generation of ROS to protect against toxicity of EGCG. Furthermore, EGCG was shown to bind to certain cellular proteins including caspase-3, PARP, andα-tubulin, but not LC3 norβ-actin, which formed EGCG-protein complexes that were inseparable by SDS-gel. On the other hand, addition of FBS or BSA to culture medium can block the binding of EGCG to these proteins.In silicodocking analysis results suggested that BSA had a stronger affinity to EGCG than the other proteins. Taken together, these data indicated that the protective effect of FBS and BSA against EGCG-induced cell death could be due to (1) the decreased generation of ROS and (2) the competitive binding of BSA to EGCG.
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Yin
Y
Zhang
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Yu-Ying
YY
Xu
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Wen-Jie
WJ
Sun
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Mo-Han
MH
Zhang
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Yi-Fan
YF
Zheng
Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597.
Han-Ming
HM
Shen
Department of Toxicology, School of Public Health, Hangzhou Normal University, 16 Xue Lin Street, Hangzhou, Zhejiang 310036, China; Collaborative Innovation Center for the Diagnosis and Treatment of Infectious Diseases, National Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Jun
J
Yang
Department of Toxicology, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
Xin-Qiang
0000-0002-9088-7906
XQ
Zhu
D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002417:Cattle; D016923:Cell Death / Q000187:drug effects; D056945:Hep G2 Cells; D006801:Humans; D042541:Intracellular Space / Q000378:metabolism*; D062105:Molecular Docking Simulation; D011485:Protein Binding / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D044967:Serum / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000494:pharmacology*
D017382:Reactive Oxygen Species; D012710:Serum Albumin, Bovine; D002392:Catechin; C045651:epigallocatechin gallate