Pu-erh tea attenuates hyperlipogenesis and induces hepatoma cells growth arrest through activating AMP-activated protein kinase (AMPK) in human HepG2 cells.
In the present study, we successively extracted the pu-erh raw tea with methanol (PR-1), chloroform (PR-2), ethyl acetate (PR-3), n-butanol (PR-4), and water (PR-5). Among these extracts, PR-3 extract contained ingredients with the most effective hypolipidemic potential and was further purified by column chromatography. Moreover, chronic administration of PR-3 provoked a significant reduction in levels of serum triglyceride and low-density lipoprotein (LDL) in rats. Our study demonstrated that fraction 5 from the PR-3 extract (PR-3-5s) showed a hypolipidemic effect in human hepatoma HepG2 cells. PR-3-5s decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Moreover, PR-3-5s blocked the progression of the cell cycle at the G1 phase by inducing p53 expression and in turn upregulating p21 expression.
Way
Tzong-Der
TD
Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung, Taiwan.
Lin
Hui-Yi
HY
Kuo
Daih-Huang
DH
Tsai
Shang-Jie
SJ
Shieh
Jia-Ching
JC
Wu
Jia-Chiun
JC
Lee
Maw-Rong
MR
Lin
Jen-Kun
JK
D055372:AMP-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000201:enzymology / Q000378:metabolism* / Q000503:physiopathology; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D050155:Lipogenesis / Q000187:drug effects*; D008297:Male; D023421:Models, Animal; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013662:Tea / Q000737:chemistry*
D010936:Plant Extracts; D013662:Tea; D055372:AMP-Activated Protein Kinases