European Journal of Nutrition

, Volume 53, Issue 1, pp 187–199 | Cite as

Epigallocatechin gallate attenuates fibrosis, oxidative stress, and inflammation in non-alcoholic fatty liver disease rat model through TGF/SMAD, PI3 K/Akt/FoxO1, and NF-kappa B pathways

  • Jia Xiao
  • Chi Tat Ho
  • Emily C. Liong
  • Amin A. Nanji
  • Tung Ming Leung
  • Thomas Yue Huen Lau
  • Man Lung Fung
  • George L. Tipoe
Original Contribution



To investigate the protective mechanisms of an 85 % pure extract of (−) epigallocatechin gallate (EGCG) in the development of fibrosis, oxidative stress and inflammation in a recently developed dietary-induced animal model of non-alcoholic fatty liver disease (NAFLD).


Female Sprague–Dawley rats were fed with either normal rat diet or high-fat diet for 8 weeks to develop NAFLD. For both treatments, rats were treated with or without EGCG (50 mg/kg, i.p. injection, 3 times per week). At the end, blood and liver tissue samples were obtained for histology, molecular, and biochemical analyses.


Non-alcoholic fatty liver disease (NAFLD) rats showed significant amount of fatty infiltration, necrosis, fibrosis, and inflammation. This was accompanied by a significant expressional increase in markers for fibrosis, oxidative stress, and inflammation. TGF/SMAD, PI3 K/Akt/FoxO1, and NF-κB pathways were also activated. Treatment with EGCG improved hepatic histology (decreased number of fatty score, necrosis, and inflammatory foci), reduced liver injury (from ~0.5 to ~0.3 of ALT/AST ratio), attenuated hepatic changes including fibrosis (reduction in Sirius Red and synaptophysin-positive stain) with down-regulation in the expressions of key pathological oxidative (e.g. nitrotyrosine formation) and pro-inflammatory markers (e.g. iNOS, COX-2, and TNF-α). EGCG treatment also counteracted the activity of TGF/SMAD, PI3 K/Akt/FoxO1, and NF-κB pathways. Treatment with EGCG did not affect the healthy rats.


Epigallocatechin gallate (EGCG) reduced the severity of liver injury in an experimental model of NAFLD associated with lower concentration of pro-fibrogenic, oxidative stress, and pro-inflammatory mediators partly through modulating the activities of TGF/SMAD, PI3 K/Akt/FoxO1, and NF-κB pathways. Therefore, green tea polyphenols and EGCG are useful supplements in the prevention of NAFLD.


EGCG NAFLD Fibrosis Oxidative stress Inflammation 

Supplementary material

394_2013_516_MOESM1_ESM.docx (14 kb)
Supplementary material 1 (DOCX 14 kb)


  1. 1.
    Harrison SA, Day CP (2007) Benefits of lifestyle modification in NAFLD. Gut 56:1760–1769CrossRefGoogle Scholar
  2. 2.
    Mendez-Sanchez N, Arrese M, Zamora-Valdes D, Uribe M (2007) Treating nonalcoholic fatty liver disease. Liver int 27:1157–1165Google Scholar
  3. 3.
    Selmi C, Bowlus CL, Keen CL, Gershwin ME (2007) Non-alcoholic fatty liver disease: the new epidemic and the need for novel nutritional approaches. J Med Food 10:563–565CrossRefGoogle Scholar
  4. 4.
    Yoneda M, Endo H, Nozaki Y, Tomimoto A, Fujisawa T, Fujita K, Yoneda K, Takahashi H, Saito S, Iwasaki T, Yamamoto S, Tsutsumi S, Aburatani H, Wada K, Hotta K, Nakajima A (2007) Life style-related diseases of the digestive system: gene expression in nonalcoholic steatohepatitis patients and treatment strategies. J Pharmacol Sci 105:151–156CrossRefGoogle Scholar
  5. 5.
    Pitt HA (2007) Hepato-pancreato-biliary fat: the good, the bad and the ugly. HPB 9:92–97CrossRefGoogle Scholar
  6. 6.
    Krasnoff JB, Painter PL, Wallace JP, Bass NM, Merriman RB (2008) Health-related fitness and physical activity in patients with nonalcoholic fatty liver disease. Hepatology (Baltimore, MD) 47:1158–1166CrossRefGoogle Scholar
  7. 7.
    McCullough AJ (2006) Pathophysiology of nonalcoholic steatohepatitis. J Clin Gastroenterol 40(Suppl 1):S17–S29Google Scholar
  8. 8.
    French SW, Takahashi H, Wong K, Mendenhall CL (1991) Ito cell activation induced by chronic ethanol feeding in the presence of different dietary fats. Alcohol Alcohol Suppl 1:357–361Google Scholar
  9. 9.
    Nanji AA (2004) Role of different dietary fatty acids in the pathogenesis of experimental alcoholic liver disease. Alcohol 34:21–25CrossRefGoogle Scholar
  10. 10.
    Lieber CS, Leo MA, Mak KM, Xu Y, Cao Q, Ren C, Ponomarenko A, DeCarli LM (2004) Model of nonalcoholic steatohepatitis. Am J Clin Nutr 79:502–509Google Scholar
  11. 11.
    Zou Y, Li J, Lu C, Wang J, Ge J, Huang Y, Zhang L, Wang Y (2006) High-fat emulsion-induced rat model of nonalcoholic steatohepatitis. Life Sci 79:1100–1107Google Scholar
  12. 12.
    Xiao J, Ching YP, Liong EC, Nanji AA, Fung ML, Tipoe GL (2012) Garlic-derived S-allylmercaptocysteine is a hepato-protective agent in non-alcoholic fatty liver disease in vivo animal model. Eur J Nutr. doi:10.1007/s00394-012-0301-0 Google Scholar
  13. 13.
    Tipoe GL, Ho CT, Liong EC, Leung TM, Lau TY, Fung ML, Nanji AA (2009) Voluntary oral feeding of rats not requiring a very high fat diet is a clinically relevant animal model of non-alcoholic fatty liver disease (NAFLD). Histol Histopathol 24:1161–1169Google Scholar
  14. 14.
    Higdon JV, Frei B (2003) Tea catechins and polyphenols: health effects, metabolism, and antioxidant functions. Crit Rev Food Sci Nutr 43:89–143CrossRefGoogle Scholar
  15. 15.
    Singh BN, Shankar S, Srivastava RK (2011) Green tea catechin, epigallocatechin-3-gallate (EGCG): mechanisms, perspectives and clinical applications. Biochem Pharmacol 82:1807–1821CrossRefGoogle Scholar
  16. 16.
    Tipoe GL, Leung TM, Hung MW, Fung ML (2007) Green tea polyphenols as an anti-oxidant and anti-inflammatory agent for cardiovascular protection. Cardiovasc Hematol Disord: Drug Targets 7:135–144CrossRefGoogle Scholar
  17. 17.
    Khan N, Afaq F, Saleem M, Ahmad N, Mukhtar H (2006) Targeting multiple signaling pathways by green tea polyphenol (−)-epigallocatechin-3-gallate. Cancer Res 66:2500–2505CrossRefGoogle Scholar
  18. 18.
    Bruno RS, Dugan CE, Smyth JA, DiNatale DA, Koo SI (2008) Green tea extract protects leptin-deficient, spontaneously obese mice from hepatic steatosis and injury. J Nutr 138:323–331Google Scholar
  19. 19.
    Fu Y, Zheng S, Lu SC, Chen A (2008) Epigallocatechin-3-gallate inhibits growth of activated hepatic stellate cells by enhancing the capacity of glutathione synthesis. Mol Pharmacol 73:1465–1473CrossRefGoogle Scholar
  20. 20.
    Kuzu N, Bahcecioglu IH, Dagli AF, Ozercan IH, Ustundag B, Sahin K (2008) Epigallocatechin gallate attenuates experimental non-alcoholic steatohepatitis induced by high fat diet. J Gastroenterol Hepatol 23:e465–e470CrossRefGoogle Scholar
  21. 21.
    Skrzydlewska E, Ostrowska J, Farbiszewski R, Michalak K (2002) Protective effect of green tea against lipid peroxidation in the rat liver, blood serum and the brain. Phytomedicine 9:232–238CrossRefGoogle Scholar
  22. 22.
    Nanji AA, Jokelainen K, Fotouhinia M, Rahemtulla A, Thomas P, Tipoe GL, Su GL, Dannenberg AJ (2001) Increased severity of alcoholic liver injury in female rats: role of oxidative stress, endotoxin, and chemokines. American journal of physiology. Gastrointest liver physiol 281:G1348–G1356Google Scholar
  23. 23.
    Cassiman D, van Pelt J, De Vos R, Van Lommel F, Desmet V, Yap SH, Roskams T (1999) Synaptophysin: a novel marker for human and rat hepatic stellate cells. Am J Pathol 155:1831–1839CrossRefGoogle Scholar
  24. 24.
    Hung MW, Tipoe GL, Poon AM, Reiter RJ, Fung ML (2008) Protective effect of melatonin against hippocampal injury of rats with intermittent hypoxia. J Pineal Res 44:214–221CrossRefGoogle Scholar
  25. 25.
    Tipoe GL, Leung TM, Liong E, So H, Leung KM, Lau TY, Tom WM, Fung ML, Fan ST, Nanji AA (2006) Inhibitors of inducible nitric oxide (NO) synthase are more effective than an NO donor in reducing carbon-tetrachloride induced acute liver injury. Histol Histopathol 21:1157–1165Google Scholar
  26. 26.
    Leung TM, Fung ML, Liong EC, Lau TY, Nanji AA, Tipoe GL (2011) Role of nitric oxide in the regulation of fibrogenic factors in experimental liver fibrosis in mice. Histol Histopathol 26:201–211Google Scholar
  27. 27.
    Nanji AA, Jokelainen K, Rahemtulla A, Miao L, Fogt F, Matsumoto H, Tahan SR, Su GL (1999) Activation of nuclear factor kappa B and cytokine imbalance in experimental alcoholic liver disease in the rat. Hepatology (Baltimore, MD) 30:934–943CrossRefGoogle Scholar
  28. 28.
    Feldstein AE, Papouchado BG, Angulo P, Sanderson S, Adams L, Gores GJ (2005) Hepatic stellate cells and fibrosis progression in patients with nonalcoholic fatty liver disease. Clin Gastroenterol Hepatol 3:384–389Google Scholar
  29. 29.
    Iredale JP (2001) Hepatic stellate cell behavior during resolution of liver injury. Semin Liver Dis 21:427–436CrossRefGoogle Scholar
  30. 30.
    Adachi M, Osawa Y, Uchinami H, Kitamura T, Accili D, Brenner DA (2007) The fork head transcription factor FoxO1 regulates proliferation and transdifferentiation of hepatic stellate cells. Gastroenterology 132:1434–1446CrossRefGoogle Scholar
  31. 31.
    dela Peña A, Leclercq I, Field J, George J, Jones B, Farrell G (2005) NF-κB activation, rather than TNF, mediates hepatic inflammation in a murine dietary model of steatohepatitis. Gastroenterology 129:1663–1674CrossRefGoogle Scholar
  32. 32.
    Butt MS, Sultan MT (2009) Green tea: nature’s defense against malignancies. Crit Rev Food Sci Nutr 49:463–473CrossRefGoogle Scholar
  33. 33.
    Chen JH, Tipoe GL, Liong EC, So HS, Leung KM, Tom WM, Fung PC, Nanji AA (2004) Green tea polyphenols prevent toxin-induced hepatotoxicity in mice by down-regulating inducible nitric oxide-derived prooxidants. American J clin nut 80:742–751Google Scholar
  34. 34.
    Chung MY, Park HJ, Manautou JE, Koo SI, Bruno RS (2012) Green tea extract protects against nonalcoholic steatohepatitis in ob/ob mice by decreasing oxidative and nitrative stress responses induced by proinflammatory enzymes. J Nutr Biochem 23:361–367CrossRefGoogle Scholar
  35. 35.
    Park HJ, Lee JY, Chung MY, Park YK, Bower AM, Koo SI, Giardina C, Bruno RS (2012) Green tea extract suppresses NFκB activation and inflammatory responses in diet-induced obese rats with nonalcoholic steatohepatitis. J Nutr 142:57–63CrossRefGoogle Scholar
  36. 36.
    Masterjohn C, Bruno RS (2012) Therapeutic potential of green tea in nonalcoholic fatty liver disease. Nutr Rev 70:41–56CrossRefGoogle Scholar
  37. 37.
    Nakagawa K, Okuda S, Miyazawa T (1997) Dose-dependent incorporation of tea catechins, (−)-epigallocatechin-3-gallate and (−)-epigallocatechin, into human plasma. Biosci Biotechnol Biochem 61:1981–1985CrossRefGoogle Scholar
  38. 38.
    Tang LX, He RH, Yang G, Tan JJ, Zhou L, Meng XM, Huang XR, Lan HY (2012) Asiatic acid inhibits liver fibrosis by blocking TGF-beta/Smad signaling in vivo and in vitro. PLoS ONE 7:e31350CrossRefGoogle Scholar
  39. 39.
    Adachi M, Brenner DA (2008) High molecular weight adiponectin inhibits proliferation of hepatic stellate cells via activation of adenosine monophosphate-activated protein kinase. Hepatology (Baltimore, MD) 47:677–685CrossRefGoogle Scholar
  40. 40.
    Chen D, Milacic V, Chen MS, Wan SB, Lam WH, Huo C, Landis-Piwowar KR, Cui QC, Wali A, Chan TH, Dou QP (2008) Tea polyphenols, their biological effects and potential molecular targets. Histol Histopathol 23:487–496Google Scholar
  41. 41.
    Frei B, Higdon JV (2003) Antioxidant activity of tea polyphenols in vivo: evidence from animal studies. J Nutr 133:3275S–3284SGoogle Scholar
  42. 42.
    Yumei F, Zhou Y, Zheng S, Chen A (2006) The antifibrogenic effect of (−)-epigallocatechin gallate results from the induction of de novo synthesis of glutathione in passaged rat hepatic stellate cells. Lab Invest 86:697–709CrossRefGoogle Scholar
  43. 43.
    Wang F, Wang LY, Wright D, Parmely MJ (1999) Redox imbalance differentially inhibits lipopolysaccharide-induced macrophage activation in the mouse liver. Infect Immun 67:5409–5416Google Scholar
  44. 44.
    Aktas O, Prozorovski T, Smorodchenko A, Savaskan NE, Lauster R, Kloetzel PM, Infante-Duarte C, Brocke S, Zipp F (2004) Green tea epigallocatechin-3-gallate mediates T cellular NF-kappa B inhibition and exerts neuroprotection in autoimmune encephalomyelitis. J immunol (Baltimore, Md.: 1950) 173:5794–5800Google Scholar
  45. 45.
    Yang F, Oz HS, Barve S, de Villiers WJ, McClain CJ, Varilek GW (2001) The green tea polyphenol (−)-epigallocatechin-3-gallate blocks nuclear factor-kappa B activation by inhibiting I kappa B kinase activity in the intestinal epithelial cell line IEC-6. Mol Pharmacol 60:528–533Google Scholar
  46. 46.
    Lin YL, Lin JK (1997) (−)-Epigallocatechin-3-gallate blocks the induction of nitric oxide synthase by down-regulating lipopolysaccharide-induced activity of transcription factor nuclear factor-kappaB. Mol Pharmacol 52:465–472Google Scholar
  47. 47.
    Gupta S, Hastak K, Afaq F, Ahmad N, Mukhtar H (2004) Essential role of caspases in epigallocatechin-3-gallate-mediated inhibition of nuclear factor kappa B and induction of apoptosis. Oncogene 23:2507–2522CrossRefGoogle Scholar
  48. 48.
    Afaq F, Adhami VM, Ahmad N, Mukhtar H (2003) Inhibition of ultraviolet B-mediated activation of nuclear factor kappaB in normal human epidermal keratinocytes by green tea Constituent (-)-epigallocatechin-3-gallate. Oncogene 22:1035–1044CrossRefGoogle Scholar
  49. 49.
    Shimizu M, Deguchi A, Joe AK, McKoy JF, Moriwaki H, Weinstein IB (2005) EGCG inhibits activation of HER3 and expression of cyclooxygenase-2 in human colon cancer cells. J Exp Ther Oncol 5:69–78Google Scholar
  50. 50.
    Nakamoto K, Takayama F, Mankura M, Hidaka Y, Egashira T, Ogino T, Kawasaki H, Mori A (2009) Beneficial effects of fermented green tea extract in a rat model of non-alcoholic steatohepatitis. J Clin Biochem Nutr 44:239–246CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Jia Xiao
    • 1
  • Chi Tat Ho
    • 2
  • Emily C. Liong
    • 2
  • Amin A. Nanji
    • 6
  • Tung Ming Leung
    • 2
    • 7
  • Thomas Yue Huen Lau
    • 5
  • Man Lung Fung
    • 3
    • 4
  • George L. Tipoe
    • 2
    • 4
  1. 1.Center for Gene and Cell Engineering, Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
  2. 2.Department of Anatomy, Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina
  3. 3.Department of Physiology, Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina
  4. 4.Research Centre of Heart, Brain, Hormone and Healthy Aging Centre, Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina
  5. 5.Department of Health Technology and Informatics, Faculty of Health and Social SciencesThe Hong Kong Polytechnic UniversityHong KongChina
  6. 6.Department of Pathology and Laboratory MedicineDalhousie University School of MedicineHalifaxCanada
  7. 7.Liver Disease Division, Department of MedicineMount Sinai School of MedicineNew York CityUSA

Personalised recommendations