[Effect of green tea flavonols on the function of the endoplasmic reticulum].
The various (e.g. anti-tumor and anti-diabetic) health effects of green tea attributed to its flavonols, primarily to epigallocatechin-gallate, got into the focus of interest. The endoplasmic reticulum, which plays key role in the metabolism of carcinogens, in the synthesis of secreted or cell surface proteins as well as in the glucose production, might be a potential target for anti-tumor and anti-diabetic agents. Therefore, it is an important question how the flavonols affect its functions. Experiments carried out in microsomes and hepatoma cells revealed that flavonols inhibit glucuronide transport in the endoplasmic reticulum, which may reduce the reactivation of carcinogens; they inhibit glucosidase II, which may cause endoplasmic reticulum stress and apoptosis in hepatoma cells; and they hinder glucose efflux, which may decrease hepatic glucose production and blood glucose level. These observations are useful for further investigation of the relevant transport processes and transporters and also contribute to the better understanding of the mechanisms of flavanol effects.
Révész
Katalin
K
Semmelweis Egyetem, Orvosi Vegytani, Molekuláris Biológiai és Patobiokémiai Intézet Budapest. reveszkati@gmail.com
Tüttô
Anna
A
Konta
Laura
L
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001786:Blood Glucose / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism*; D044948:Flavonols / Q000494:pharmacology*; D020719:Glucuronides / Q000378:metabolism; D065089:Glycoside Hydrolase Inhibitors; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism; D008861:Microsomes / Q000187:drug effects; D013662:Tea; D000520:alpha-Glucosidases
D000970:Antineoplastic Agents; D001786:Blood Glucose; D044948:Flavonols; D020719:Glucuronides; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate; C034251:4-nitrophenyl-alpha-glucosidase; D000520:alpha-Glucosidases