A zöld tea sokrétű egészségmegőrző (pl. tumorellenes és antidiabetikus) hatásai, melyek a flavanoloknak, közülük is elsősorban az epigallokatechin-gallátnak tulajdoníthatók, felkeltették a kutatók érdeklődését. Az endoplazmás retikulum a karcinogén mérgek metabolizmusában, a sejtfelszíni és szekretált fehérjék szintézisében, illetve a glükóztermelésben betöltött szerepe miatt a tumorellenes és antidiabetikus hatóanyagok kiváló célpontja lehet, ezért fontos kérdés, hogyan befolyásolják működését a teaflavanolok. Mikroszómán és hepatomasejteken végzett kísérletek eredményei azt mutatják, hogy a flavanolok az endoplazmás retikulumban gátolják a glukuronidtranszportot, így csökkenthetik a rákkeltő anyagok reaktiválását; gátolják a glukozidáz II enzimet, ami endoplazmás retikulum stresszt és apoptosist idézhet elő hepatomasejtekben; és akadályozzák a glükózkiáramlást, amely a máj glükóztermelését és így a vércukorszintet csökkentheti. Ezek a megfigyelések egyrészt az érintett transzportfolyamatok, illetve transzporterek további vizsgálata szempontjából fontosak, másrészt hozzájárulnak a flavanolok hatásmechanizmusának jobb megértéséhez is.
Cabrera, C., Artacho, R., Gimenez, R.: Beneficial effects of green tea – a review. J. Am. Coll. Nutr., 2006, 25 , 79–99.
Gimenez R. , 'Beneficial effects of green tea – a review ' (2006 ) 25 J. Am. Coll. Nutr. : 79 -99 .
Balentine, D. A., Wiseman, S. A., Bouwens, L. C.: The chemistry of tea flavonoids. Crit. Rev. Food Sci. Nutr., 1997, 37 , 693–704.
Bouwens L. C. , 'The chemistry of tea flavonoids ' (1997 ) 37 Crit. Rev. Food Sci. Nutr. : 693 -704 .
Cheynier, V.: Polyphenols in foods are more complex than often thought. Am. J. Clin. Nutr., 2005, 81 , 223S–229S.
Cheynier V. , 'Polyphenols in foods are more complex than often thought ' (2005 ) 81 Am. J. Clin. Nutr. : 223S -229S .
Csala M., Banhegyi G., Benedetti, A.: Endoplasmic reticulum: a metabolic compartment. FEBS Lett., 2006, 580 , 2160–2165.
Benedetti A. , 'Endoplasmic reticulum: a metabolic compartment ' (2006 ) 580 FEBS Lett. : 2160 -2165 .
Brown, J., Novak, E. K., Takeuchi, K. és mtsai: Lumenal location of the microsomal beta-glucuronidase-egasyn complex. J. Cell Biol., 1987, 105 , 1571–1578.
Takeuchi K. , 'Lumenal location of the microsomal beta-glucuronidase-egasyn complex ' (1987 ) 105 J. Cell Biol. : 1571 -1578 .
Lizak, B., Czegle I., Csala M. és mtsai.: Translocon Pores in the Endoplasmic Reticulum Are Permeable to Small Anions. Am. J. Physiol. Cell. Physiol., 2006, 291 , C511–C517.
Csala M. , 'Translocon Pores in the Endoplasmic Reticulum Are Permeable to Small Anions ' (2006 ) 291 Am. J. Physiol. Cell. Physiol. : C511 -C517 .
Banhegyi G., Braun, L., Marcolongo, P. és mtsai: Evidence for an UDP-glucuronic acid/phenol glucuronide antiport in rat liver microsomal vesicles. Biochem. J., 1996, 315 , 171–176.
Marcolongo P. , 'Evidence for an UDP-glucuronic acid/phenol glucuronide antiport in rat liver microsomal vesicles ' (1996 ) 315 Biochem. J. : 171 -176 .
Csala M., Staines, A. G., Banhegyi G. és mtsai: Evidence for multiple glucuronide transporters in rat liver microsomes. Biochem. Pharmacol., 2004, 68 , 1353–1362.
Banhegyi G. , 'Evidence for multiple glucuronide transporters in rat liver microsomes ' (2004 ) 68 Biochem. Pharmacol. : 1353 -1362 .
Csala M., Banhegyi G., Braun L. és mtsai: Beta-glucuronidase latency in isolated murine hepatocytes. Biochem. Pharmacol., 2000, 59 , 801–805.
Braun L. , 'Beta-glucuronidase latency in isolated murine hepatocytes ' (2000 ) 59 Biochem. Pharmacol. : 801 -805 .
Revesz K., Tutto, A., Margittai E. és mtsai: Glucuronide transport across the endoplasmic reticulum membrane is inhibited by epigallocatechin gallate and other green tea polyphenols. Int. J. Biochem. Cell Biol., 2007, 39 , 922–930.
Margittai E. , 'Glucuronide transport across the endoplasmic reticulum membrane is inhibited by epigallocatechin gallate and other green tea polyphenols ' (2007 ) 39 Int. J. Biochem. Cell Biol. : 922 -930 .
Boyland, E., Gasson, J. E., Williams, D. C.: Enzyme activity in relation to cance. the urinary beta-glucuronidase activity of patients suffering from malignant disease.; Br. J. Cancer, 1957, 11 , 120–129.
Williams D. C. , 'Enzyme activity in relation to cance ' (1957 ) 11 the urinary beta-glucuronidase activity of patients suffering from malignant disease.; Br. J. Cancer : 120 -129 .
Gupta, K. P., Singh, J.: Modulation of carcinogen metabolism and DNA interaction by calcium glucarate in mouse skin. Toxicol. Sci., 2004, 79 , 47–55.
Singh J. , 'Modulation of carcinogen metabolism and DNA interaction by calcium glucarate in mouse skin ' (2004 ) 79 Toxicol. Sci. : 47 -55 .
Banhegyi G., Csala M., Nagy G. és mtsai: Evidence for the transport of glutathione through ryanodine receptor channel type 1. Biochem. J., 2003, 376 , 807–812.
Nagy G. , 'Evidence for the transport of glutathione through ryanodine receptor channel type 1 ' (2003 ) 376 Biochem. J. : 807 -812 .
Csala M., Senesi, S., Banhegyi G. és mtsai: Characterization of sulfate transport in the hepatic endoplasmic reticulum. Arch. Biochem. Biophys., 2005, 440 , 173–180.
Banhegyi G. , 'Characterization of sulfate transport in the hepatic endoplasmic reticulum ' (2005 ) 440 Arch. Biochem. Biophys. : 173 -180 .
Staines, A. G., Burchell, B., Banhegyi G. és mtsai: Application of high-performance liquid chromatography-electrospray ionization-mass spectrometry to measure microsomal membrane transport of glucuronides. Anal. Biochem., 2005, 342 , 45–52.
Banhegyi G. , 'Application of high-performance liquid chromatography-electrospray ionization-mass spectrometry to measure microsomal membrane transport of glucuronides ' (2005 ) 342 Anal. Biochem. : 45 -52 .
Tu, B. P., Weissman, J. S.: Oxidative protein folding in eukaryotes: mechanisms and consequences. J. Cell Biol., 2004, 164 , 341–346.
Weissman J. S. , 'Oxidative protein folding in eukaryotes: mechanisms and consequences ' (2004 ) 164 J. Cell Biol. : 341 -346 .
Kornfeld, R., Kornfeld, S.: Assembly of asparagine-linked oligosaccharides. Annu. Rev. Biochem., 1985, 54 , 631–664.
Kornfeld S. , 'Assembly of asparagine-linked oligosaccharides ' (1985 ) 54 Annu. Rev. Biochem. : 631 -664 .
Ruddock, L. W., Molinari, M.: N-glycan processing in ER quality control. J. Cell. Sci., 2006, 119 , 4373–4380.
Molinari M. , 'N-glycan processing in ER quality control ' (2006 ) 119 J. Cell. Sci. : 4373 -4380 .
Szegezdi E., Logue, S. E., Gorman, A. M. és mtsai: Mediators of endoplasmic reticulum stress-induced apoptosis. EMBO Rep., 2006, 7 , 880–885.
Gorman A. M. , 'Mediators of endoplasmic reticulum stress-induced apoptosis ' (2006 ) 7 EMBO Rep. : 880 -885 .
Banhegyi G., Braun L., Csala M. és mtsai: Ascorbate metabolism and its regulation in animals. Free Radic. Biol. Med., 1997, 23 , 793–803.
Csala M. , 'Ascorbate metabolism and its regulation in animals ' (1997 ) 23 Free Radic. Biol. Med. : 793 -803 .
Banhegyi G., Csala M., Szarka A. és mtsai: Role of ascorbate in oxidative protein folding. Biofactors, 2003, 17 , 37–46.
Szarka A. , 'Role of ascorbate in oxidative protein folding ' (2003 ) 17 Biofactors : 37 -46 .
Szarka A., Stadler, K., Jenei V. és mtsai: Ascorbyl free radical and dehydroascorbate formation in rat liver endoplasmic reticulum. J. Bioenerg. Biomembr., 2002, 34 , 317–323.
Jenei V. , 'Ascorbyl free radical and dehydroascorbate formation in rat liver endoplasmic reticulum ' (2002 ) 34 J. Bioenerg. Biomembr. : 317 -323 .
Csala M., Mile, V., Benedetti, A. és mtsai: Ascorbate oxidation is a prerequisite for its transport into rat liver microsomal vesicles. Biochem. J., 2000, 349 , 413–415.
Benedetti A. , 'Ascorbate oxidation is a prerequisite for its transport into rat liver microsomal vesicles ' (2000 ) 349 Biochem. J. : 413 -415 .
Csala M., Braun, L., Mile, V. és mtsai: Ascorbate-mediated electron transfer in protein thiol oxidation in the endoplasmic reticulum. FEBS Lett., 1999, 460 , 539–543.
Mile V. , 'Ascorbate-mediated electron transfer in protein thiol oxidation in the endoplasmic reticulum ' (1999 ) 460 FEBS Lett. : 539 -543 .
Nardai G., Braun L., Csala M. és mtsai: Protein-disulfide isomerase- and protein thiol-dependent dehydroascorbate reduction and ascorbate accumulation in the lumen of the endoplasmic reticulum. J. Biol. Chem., 2001, 276 , 8825–8828.
Csala M. , 'Protein-disulfide isomerase- and protein thiol-dependent dehydroascorbate reduction and ascorbate accumulation in the lumen of the endoplasmic reticulum ' (2001 ) 276 J. Biol. Chem. : 8825 -8828 .
Csala M., Szarka A., Margittai E. és mtsai: Role of vitamin E in ascorbate-dependent protein thiol oxidation in rat liver endoplasmic reticulum. Arch. Biochem. Biophys., 2001, 388 , 55–59.
Margittai E. , 'Role of vitamin E in ascorbate-dependent protein thiol oxidation in rat liver endoplasmic reticulum ' (2001 ) 388 Arch. Biochem. Biophys. : 55 -59 .
Margittai E., Banhegyi G., Kiss A. és mtsai: Scurvy leads to endoplasmic reticulum stress and apoptosis in the liver of Guinea pigs. J. Nutr., 2005, 135 , 2530–2534.
Kiss A. , 'Scurvy leads to endoplasmic reticulum stress and apoptosis in the liver of Guinea pigs ' (2005 ) 135 J. Nutr. : 2530 -2534 .
Gamberucci, A., Konta, L., Colucci, A. és mtsai: Green tea flavonols inhibit glucosidase II. Biochem. Pharmacol., 2006, 72 , 640–646.
Colucci A. , 'Green tea flavonols inhibit glucosidase II ' (2006 ) 72 Biochem. Pharmacol. : 640 -646 .
Waltner-Law, M. E., Wang, X. L., Law, B. K. és mtsai: Epigallocatechin gallate, a constituent of green tea, represses hepatic glucose production. J. Biol. Chem., 2002, 277 , 34933–34940.
Law B. K. , 'Epigallocatechin gallate, a constituent of green tea, represses hepatic glucose production ' (2002 ) 277 J. Biol. Chem. : 34933 -34940 .
Csala M., Marcolongo, P., Lizak, B. és mtsai: Transport and transporters in the endoplasmic reticulum. Biochim. Biophys. Acta, 2007, 1768 , 1325–1341.
Lizak B. , 'Transport and transporters in the endoplasmic reticulum ' (2007 ) 1768 Biochim. Biophys. Acta : 1325 -1341 .
Belkaid, A., Copland, I. B., Massillon, D. és mtsai: Silencing of the human microsomal glucose-6-phosphate translocase induces glioma cell death: potential new anticancer target for curcumin. FEBS Lett., 2006, 580 , 3746–3752.
Massillon D. , 'Silencing of the human microsomal glucose-6-phosphate translocase induces glioma cell death: potential new anticancer target for curcumin ' (2006 ) 580 FEBS Lett. : 3746 -3752 .
Csala M., Margittai E., Senesi, S. és mtsai: Inhibition of hepatic glucose 6-phosphatase system by the green tea flavanol epigallocatechin gallate. FEBS Lett., 2007, 581 , 1693–1698.
Senesi S. , 'Inhibition of hepatic glucose 6-phosphatase system by the green tea flavanol epigallocatechin gallate ' (2007 ) 581 FEBS Lett. : 1693 -1698 .
Anton, S., Melville, L., Rena, G.: Epigallocatechin gallate (EGCG) mimics insulin action on the transcription factor FOXO1a and elicits cellular responses in the presence and absence of insulin. Cell. Signal., 2007, 19 , 378–383.
Rena G. , 'Epigallocatechin gallate (EGCG) mimics insulin action on the transcription factor FOXO1a and elicits cellular responses in the presence and absence of insulin ' (2007 ) 19 Cell. Signal. : 378 -383 .
Chow, H. H., Cai, Y., Hakim, I. A. és mtsai: Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals. Clin. Cancer Res., 2003, 9 , 3312–3319.
Hakim I. A. , 'Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals ' (2003 ) 9 Clin. Cancer Res. : 3312 -3319 .
Miyazawa, T.: Absorption, metabolism and antioxidative effects of tea catechin in humans. Biofactors, 2000, 13 , 55–59.
Miyazawa T. , 'Absorption, metabolism and antioxidative effects of tea catechin in humans ' (2000 ) 13 Biofactors : 55 -59 .
Kao, Y. H., Hiipakka, R. A., Liao, S.: Modulation of endocrine systems and food intake by green tea epigallocatechin gallate. Endocrinology, 2000, 141 , 980–987.
Liao S. , 'Modulation of endocrine systems and food intake by green tea epigallocatechin gallate ' (2000 ) 141 Endocrinology : 980 -987 .
Koyama, Y., Abe, K., Sano, Y. és mtsai: Effects of green tea on gene expression of hepatic gluconeogenic enzymes in vivo. Planta Med., 2004, 70 , 1100–1102.
Sano Y. , 'Effects of green tea on gene expression of hepatic gluconeogenic enzymes in vivo ' (2004 ) 70 Planta Med. : 1100 -1102 .
Wolfram, S., Raederstorff, D., Preller, M. és mtsai: Epigallocatechin gallate supplementation alleviates diabetes in rodents. J. Nutr., 2006, 136 , 2512–2518.
Preller M. , 'Epigallocatechin gallate supplementation alleviates diabetes in rodents ' (2006 ) 136 J. Nutr. : 2512 -2518 .