title: Antioxidative effects of Alisma orientale extract in palmitate-induced cellular injury.
abstract: BACKGROUND
  Alisma orientale (Sam.) Juzepczuk (Alismataceae) is an indigenous medicinal herb that has been traditionally used for diuretic, hypolipidemic, anti-inflammatory, and antidiabetic proposes in northern and eastern Asia.
  
  
  OBJECTIVE
  This study examined the mechanisms underlying the cytoprotective effect of an aqueous extract of A. orientale (AEAO) against long-chain saturated fatty acid-induced cellular injury.
  
  
  METHODS
  HepG2 cells were treated with 0.5 mM palmitate to generate a cellular model of nonalcoholic fatty liver disease (NAFLD). Using this cellular model, the cytoprotective effect of AEAO (100 µg/mL) against long-chain saturated fatty acid-induced cellular injury was evaluated by measuring the steatosis, ROS accumulation, and apoptosis.
  
  
  RESULTS
  AEAO significantly attenuated palmitate-induced intracellular steatosis and cellular damage up to 54 and 33%, respectively. Palmitate-induced intracellular levels of reactive oxygen species (ROS) and reactive aldehydes were significantly reduced in the presence of AEAO to 40 and 75%, respectively, suggesting that oxidative stress plays a role in the palmitate-induced damage. AEAO inhibited the palmitate-mediated activation of c-Jun NH(2)-terminal kinase (JNK), a kinase that is correlated with NAFLD. Inhibition of JNK by SP600125 or addition of AEAO significantly reduced palmitate-induced steatosis, ROS accumulation, and apoptosis, indicating that the protective effects of AEAO against palmitate-induced cellular damage result from blocking ROS-activated JNK signaling.
  
  
  CONCLUSIONS
  The combined properties of AEAO in cellular steatosis and ROS production are beneficial for treating NAFLD, which includes complex metabolic changes, such that modulation of a single target is often not sufficient to achieve the desired therapeutic effect.
authors.affiliation: Department of Internal Medicine, Pusan National University School of Korean Medicine, Yangsan, Korea.
authors.forename: Chang Woo
authors.initials: CW
authors.lastname: Han
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Kang
authors.forename: Sun Ah
authors.initials: SA
authors.lastname: Ham
authors.forename: Hong Jung
authors.initials: HJ
authors.lastname: Woo
authors.forename: Jang Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Han Geuk
authors.initials: HG
authors.lastname: Seo
mesh_terms: D034902:Alisma / Q000737:chemistry*; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular; D019610:Cytoprotection / Q000187:drug effects; D005234:Fatty Liver / Q000188:drug therapy / Q000473:pathology*; D056945:Hep G2 Cells; D018197:Hepatoblastoma / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008518:Medicine, East Asian Traditional; D065626:Non-alcoholic Fatty Liver Disease; D018384:Oxidative Stress / Q000187:drug effects; D010168:Palmitates / Q000633:toxicity; D010936:Plant Extracts / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D010168:Palmitates; D010936:Plant Extracts; D017382:Reactive Oxygen Species