title: Eremophila maculata-Isolation of a rare naturally-occurring lignan glycoside and the hepatoprotective activity of the leaf extract.
abstract: BACKGROUND
  The Australian plant Eremophila maculata F. Muell (Scrophulariaceae) is cultivated worldwide as an ornamental plant.
  
  
  OBJECTIVE
  This study was designed to assess the antioxidant and hepatoprotective activities of a methanol extract from E. maculata leaves (EMM) both in vitro and in vivo (rats) experiments. Detailed phytochemical study was done on the extract followed by molecular docking experiments on TNF-α ascertain the efficacy of the isolated compounds.
  
  
  METHODS
  The antiproliferative activity was evaluated in the human cancer cell lines A-495, PC3 and HepG2 cells using the SRB method. The antioxidant activitywas evaluated in vitro using the DPPH• assay while the hepatoprotective properties were investigated by determining the amelioration of CCl4-induced cytotoxicity and oxidative stress in HepG2 cells. The activity was confirmed in vivo by studying tamoxifen-induced hepatotoxicity in rats. An in-depth phytochemical investigation of a methanol extract was performed using 1D and 2D NMR experiments. In silico molecular modeling studies of the isolated compounds on TNF-α (PDB ID 2AZ5) were carried out using Discovery Studio 2.5 software applying C-Docker protocol.
  
  
  RESULTS
  The IC50values of EMM were >500µg/ml for both PC3 and HepG2 cells indicating its safety. Similar to the standard drug silymarin, EMM could restore AST, ALT values; replenish GSH level, SOD activity and TAC in vitro. The hepatoprotective activity was confirmed in vivo in which the extract (20mg/kg body weight) decreased ALT and AST levels by 45.23 and 45.79%, respectively as compared to the tamoxifen treated groups. Oxidative stress was reduced by lowering of thiobarbituric acid reactive substances by 28.57%. Additionally, hepatocyte inflammation was improved by reducing the pro-inflammatory mediator TNF-α by 54.29%. Phytochemical investigation resulted in the isolation of a rare naturally-occurring lignan glycoside, namely pinoresinol-4-O-[6″-O-(E)-feruloyl]-β-D-glucopyranoside for the first time from the Scrophulariaceae in addition to 12 known compounds.Pinoresinol-4-O-[6''-O-(E)-feruloyl]-β-D-glucopyranoside was the strongest inhibitor of TNF-α as evidenced from its higher fitting scores comparable to lead compound.
  
  
  CONCLUSIONS
  These findings highlighted for the first time that EMM could be an interesting candidate as a safe, natural liver supplement for relieving of various hepatic disorders and counteracting the effect of many xenobiotics.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt.
authors.forename: Fadia S
authors.initials: FS
authors.lastname: Youssef
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt; Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany. Electronic address: mohamed_ashour@pharm.asu.edu.eg.
authors.forename: Mohamed L
authors.initials: ML
authors.lastname: Ashour
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany.
authors.forename: Mansour
authors.initials: M
authors.lastname: Sobeh
authors.affiliation: Medical Laboratories Technology Department, Faculty of Applied Medical Sciences, Taibah University, Al- Madinah Al-Munwarah, Saudi Arabia.
authors.forename: Hesham A
authors.initials: HA
authors.lastname: El-Beshbishy
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt.
authors.forename: Abdel Nasser
authors.initials: AN
authors.lastname: Singab
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany. Electronic address: wink@uni-heidelberg.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Wink
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D001315:Australia; D002251:Carbon Tetrachloride; D002301:Cardiac Glycosides / Q000494:pharmacology; D005260:Female; D005663:Furans / Q000494:pharmacology*; D006027:Glycosides / Q000494:pharmacology*; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D006801:Humans; D017705:Lignans / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D008297:Male; D062105:Molecular Docking Simulation; D018384:Oxidative Stress / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D017207:Rats, Sprague-Dawley; D028083:Scrophulariaceae / Q000737:chemistry*; D012838:Silymarin / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002301:Cardiac Glycosides; D005663:Furans; D006027:Glycosides; D017705:Lignans; D010936:Plant Extracts; D012838:Silymarin; D014409:Tumor Necrosis Factor-alpha; D002251:Carbon Tetrachloride; C103298:pinoresinol
keywords: Antioxidant activity; Eremophila maculata; Hepatoprotection; Lignans; Molecular docking; Phenylpropanoids