title: Nelumbo nucifera leaves protect hydrogen peroxide-induced hepatic damage via antioxidant enzymes and HO-1/Nrf2 activation.
abstract: Naturally occurring phenolic compounds are widely found in plants. Here, the phenolic composition and hepatoprotective effect of the butanolic extract (BE) from Nelumbo nucifera leaves against H2O2-induced hepatic damage in cultured hepatocytes were investigated. BE showed high total phenol and flavonoid contents, and major phenolic compounds are quercetin, catechin, ferulic acid, rutin, and protocatechuic acid by HPLC analysis. BE effectively scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) cation radicals (IC50 values of 5.21 μg mL(-1) for DPPH and 6.22 μg mL(-1) for ABTS(+)) and showed strong reducing power. Pretreatment of BE prior to 650 μM H2O2 exposure markedly increased cell viability and suppressed H2O2-induced intracellular reactive oxygen species generation and AAPH-induced cell membrane lipid peroxidation. In addition, BE up-regulated intracellular glutathione levels under normal and oxidative stress conditions. Notably, the hepatoprotective effect of BE was directly correlated with the increased expression of superoxide dismutase-1 (SOD-1) by 0.62-fold, catalase (CAT) by 0.42-fold, and heme oxygenase-1 (HO-1) by 2.4-fold. Pretreatment of BE also increased the nuclear accumulation of Nrf2 by 8.1-fold indicating that increased SOD-1, CAT, and HO-1 expressions are Nrf2-mediated.
authors.affiliation: Department of Marine-Bio Convergence Science, Pukyong National University, Busan 608-737, Republic of Korea. jjy1915@pknu.ac.kr.
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Je
authors.forename: Da-Bin
authors.initials: DB
authors.lastname: Lee
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000627:therapeutic use; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D056486:Chemical and Drug Induced Liver Injury / Q000378:metabolism / Q000517:prevention & control; D019587:Dietary Supplements / Q000032:analysis; D004789:Enzyme Activation; D005419:Flavonoids / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use; D005978:Glutathione / Q000819:agonists / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000737:chemistry / Q000378:metabolism*; D022781:Hepatocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors / Q000633:toxicity; D015227:Lipid Peroxidation / Q000187:drug effects; D051267:NF-E2-Related Factor 2 / Q000819:agonists* / Q000378:metabolism; D031653:Nelumbo / Q000737:chemistry*; D018384:Oxidative Stress / Q000187:drug effects; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D010636:Phenols / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000627:therapeutic use; D018515:Plant Leaves / Q000737:chemistry; D056910:Republic of Korea
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D010636:Phenols; D010936:Plant Extracts; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D005978:Glutathione