title: Bioactivites of two common polyphenolic compounds: Verbascoside and catechin.
abstract: BACKGROUND
  Natural products can present remarkable biological and pharmacological activities. In traditional medicine, plants have been used historically in treating cancer, infections, and other inflammatory conditions.
  
  
  OBJECTIVE
  Verbascoside and catechin are widespread polyphenolic plant compounds that could play a role in the anti-inflammatory and health-promoting effects of plants and plant extracts.
  
  
  METHODS
  This study compares the potential cytotoxic effects of polyphenols verbascoside and catechin (6.25-200 µM) on human peripheral blood mononuclear cells (PBMC) for 48 h and myelomonocytic THP-1 and THP-1 Blue cells for 24 h. The effects of the compounds on immune activation markers such as indoleamine 2,3-dioxygenase (IDO) activity as well as on neopterin formation and nuclear factor-κB (NF-κB) activation were investigated. Cytotoxicity of the compounds was tested using Cell-Titer Blue assay.
  
  
  RESULTS
  Verbascoside exhibited significant suppressive effects in mitogen-stimulated PBMC on tryptophan breakdown (>50 µM; IC50 value: 58.6 µM) and the production of neopterin (>6.25 µM; IC50 value: 217 µM). These effects correlated with a decline in cell viability, while THP-1 Blue cells were less sensitive. NF-κB activity was slightly enhanced at lower concentrations (<50 µM verbascoside) in stimulated cells and at the highest concentration used in unstimulated cells. Catechin had no relevant effects on cell viability and on the tested inflammation markers, except NF-κB activation in THP-1 Blue cells.
  
  
  CONCLUSIONS
  The results obtained show that verbascoside and catechin represent effective compounds which interfere with immunobiochemical pathways that are highly relevant for immunosurveillance and competing virus infections.
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Yeditepe University , Kayisdagi , Istanbul , Turkey .|b Division of Biological Chemistry , Biocenter, Medical University , Innsbruck , Austria .
authors.forename: Hande
authors.initials: H
authors.lastname: Sipahi
authors.affiliation: c Division of Medical Biochemistry , Biocenter, Medical University , Innsbruck , Austria .
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Gostner
authors.affiliation: b Division of Biological Chemistry , Biocenter, Medical University , Innsbruck , Austria .
authors.forename: Kathrin
authors.initials: K
authors.lastname: Becker
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Yeditepe University , Kayisdagi , Istanbul , Turkey .
authors.forename: Mohammad
authors.initials: M
authors.lastname: Charehsaz
authors.affiliation: d Department of Pharmacognosy , Faculty of Pharmacy, Yeditepe University , Kayisdagi , Istanbul , Turkey , and.
authors.forename: Hasan
authors.initials: H
authors.lastname: Kirmizibekmez
authors.affiliation: e Central Institute of Blood Transfusion and Immunology, University Clinics , Innsbruck , Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Schennach
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Yeditepe University , Kayisdagi , Istanbul , Turkey .
authors.forename: Ahmet
authors.initials: A
authors.lastname: Aydin
authors.affiliation: b Division of Biological Chemistry , Biocenter, Medical University , Innsbruck , Austria .
authors.forename: Dietmar
authors.initials: D
authors.lastname: Fuchs
mesh_terms: D002392:Catechin / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D006801:Humans; D020902:Hypericum; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000502:physiology; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000068377:Plantaginaceae; D059808:Polyphenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D059808:Polyphenols; D002392:Catechin
keywords: (+)-Catechin; NF-κB; cytotoxicity kynurenine; neopterin; tryptophan