title: Effects of globularifolin on cell survival, nuclear factor-κB activity, neopterin production, tryptophan breakdown and free radicals in vitro.
abstract: The potential effects of globularifolin, an acylated iridoid glucoside, on cell survival, inflammation markers and free radicals scavenging were investigated. Viability assay on human myelomomonocytic cell line THP-1 and human peripheral blood mononuclear cells (PBMC) using the Cell-Titer Blue assay proved that globularifolin had no toxic effect at the tested concentrations. Conversely, it is proportional to the dose globularifolin increased growth of THP-1 cells (p <0.01). On human PBMC, globularifolin at 6.25 and 12.5 μM concentrations showed a stimulatory effect, while at 12.5-200 μM it suppressed response of PBMC to stimulation with phytohemagglutinin (PHA). Globularifolin (50-200 μM) enhanced neopterin formation dose-dependently, whereas tryptophan breakdown was not influenced. At 50-200 μM in unstimulated PBMC in THP-1 cells, globularifolin induced a significant expression of nuclear factor-κB (NF-κB) as was quantified by Quanti-Blue assay. By contrast, in lipopolysaccharide (LPS)-stimulated cells, the higher concentrations of globularifolin suppressed NF-κB expression dose-dependently and a significant decrease was observed at 200 μM concentration. A positive correlation was found between increased neopterin and NF-κB activity (p <0.01). Similarly, a positive correlation was observed between neopterin levels in mitogen-induced cells and NF-κB activity in LPS-stimulated cells after treatment with globularifolin (p=0.001). The free radical scavenging capacity of globularifolin evaluated by Oxygen Radical Absorbance Capacity (ORAC) assay showed relative ORAC values of 0.36±0.05 μmol Trolox equivalent/μmol. All together, results show that natural antioxidant globularifolin might represent a potential immunomodulatory as well as proliferative agent, which deserves further in vitro and in vivo studies.
authors.affiliation: Department of Toxicology, Faculty of Pharmacy, Yeditepe University, Kayisdagi, Istanbul, Turkey; Divisions of Biological Chemistry, Biocenter, Medical University, Innsbruck, Austria.
authors.forename: Hande
authors.initials: H
authors.lastname: Sipahi
authors.affiliation: Medical Biochemistry, Biocenter, Medical University, Innsbruck, Austria.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Becker
authors.affiliation: Medical Biochemistry, Biocenter, Medical University, Innsbruck, Austria.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Gostner
authors.affiliation: Department of Toxicology, Faculty of Pharmacy, Yeditepe University, Kayisdagi, Istanbul, Turkey.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Charehsaz
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Yeditepe University, Kayisdagi, Istanbul, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Kirmizibekmez
authors.affiliation: Central Institute of Blood Transfusion and Immunology, University Clinics, Innsbruck, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Schennach
authors.affiliation: Department of Toxicology, Faculty of Pharmacy, Yeditepe University, Kayisdagi, Istanbul, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Aydin
authors.affiliation: Medical Biochemistry, Biocenter, Medical University, Innsbruck, Austria. Electronic address: dietmar.fuchs@i-med.ac.at.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Fuchs
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005609:Free Radicals / Q000378:metabolism*; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology; D018836:Inflammation Mediators / Q000378:metabolism; D057888:Iridoid Glucosides / Q000494:pharmacology*; D007948:Leukemia, Monocytic, Acute / Q000276:immunology / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000378:metabolism; D008070:Lipopolysaccharides; D008934:Mitogens / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism*; D019798:Neopterin / Q000096:biosynthesis*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology; D010943:Plantago / Q000737:chemistry; D014364:Tryptophan / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D007155:Immunologic Factors; D018836:Inflammation Mediators; D057888:Iridoid Glucosides; D008070:Lipopolysaccharides; D008934:Mitogens; D016328:NF-kappa B; D010936:Plant Extracts; C000591472:globularifolin; D019798:Neopterin; D014364:Tryptophan
keywords: 2,2′-azobis(2-amidinopropane) dihydrochloride; 6-hydroxy- 2,5,7,8-tetramethyl-2-carboxylic acid; AAPH; Antioxidant activity; CTB; Cell-Titer Blue®; Cytotoxicity; FCS; FL; Globularifolin; HAT; IDO; IFN-γ; Immunomodulatory; Immunosuppressive; Iridoid glycoside; NF-κB; ORAC; PBMC; PHA; SEAP; TNF-α; Trolox; fetal calf serum; fluorescein; hydrogen atom transfer; indoleamine (2,3)-dioxygenase; interferon gamma; kyn; kynurenine; neop; neopterin; nuclear factor-κB; oxygen radical absorbance capacity; peripheral blood mononuclear cells; phytohemagglutinin; secreted embryonic alkaline phosphatase; trp; tryptophan; tumor necrosis factor alpha