Protective effects of protein hydrolysate from marine microalgae Navicula incerta on ethanol-induced toxicity in HepG2/CYP2E1 cells

• Published in: Food chemistry 2012-05, Vol.132 (2), p.677-685
• Main Authors: Kang, Kyong-Hwa, Qian, Zhong-Ji, Ryu, BoMi, Kim, Daekyung, Kim, Se-Kwon
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; culture media; Cytotoxicity; ethanol; Food industries; functional foods; Fundamental and applied biological sciences. Psychology; hepatocytes; hepatotoxicity; HepG2/CYP2E1; humans; Hydrolysates; Liver injury; Microalgae; Navicula; Navicula incerta; oxidative stress; papain; protective effect; protein hydrolysates; viability
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2011.10.031

► Microalgae Navicula incerta extract was hydrolysed by several enzymes. ► Navicula enzymatic hydrolysates (NEHs) were assayed for liver protection against ethanol-induced toxicity. ► NEHs were showed to regulate the ethanol-induced change in GGT and GSH levels. ► NEHs protected HepG2/CYP2E1 cells from ethanol-induced damage. Ethanol is independently known to cause tissue damage through various mechanisms. This study was designed to evaluate the protective effect of marine microalgae, Navicula incerta protein enzymatic hydrolysates (NEHs) against ethanol-induced hepatotoxicity in HepG2 cells transfected with human CYP2E1. Induction of CYP2E1 by ethanol is one of the central pathways by which ethanol generates a state of oxidative stress in hepatocytes. When the alcohol-induced cells were treated with NEHs at various concentrations, there was a dose-dependent decrease of gamma-glutamyl transpeptidase (GGT) activity in the culture media and loss of cell viability. Among the NEHs constituents the hydrolysates which were obtained by papain (P-NEH), pronase-E (PR-NEH) and α-chymotrypsin (A-NEH) activity attenuated the ethanol cytotoxicity effectively, respectively. The activity appeared to be a GGT inhibitor. Therefore, the cytoprotective effects at alcohol-induced HepG2/CYP2E1 cells could be attributed to the inhibition of GGT activity by NEHs. This study suggests that NEHs have enough potential to be considered as highly active compounds against ethanol toxicity which leads NEHs to be significant nutraceuticals.