title: Effects of carrageenan on cell permeability, cytotoxicity, and cytokine gene expression in human intestinal and hepatic cell lines.
abstract: Carrageenan (CGN) is a common food additive used for its gelling and thickening properties. The present study was done to evaluate intestinal permeability, cytotoxicity, and CGN-mediated induction of proinflammatory cytokines. A standard Caco-2 absorption model showed no CGN permeability or cytotoxicity at concentrations of 100, 500, and 1000 μg/mL. In two human intestinal cell lines (HT-29 and HCT-8) CGN (0.1, 1.0, and 10.0 μg/mL) did not induce IL-8, IL-6, or MCP-1 (CCL2) or produce cellular toxicity after 24 h. The TLR4 agonist LPS produced weak induction of IL-8 in HT-29 cells and no induction in HCT-8 cells. The effects of κ-CGN (0.1, 1.0, and 10 μg/mL) on cellular oxidative stress was assessed in HT-29 cells using CM-H2DCFDA as the probe. No effect on oxidative stress was observed after 24 h. In the human (HepG2) liver cell line, ʎ-CGN (0.1, 1.0, 10.0 and 100.0 μg/mL) had no effect on the expression of IL-8, IL-6, or MCP-1 (CCL2) after 24 h. In conclusion, CGN was not absorbed, and was not cytotoxic. It did not induce oxidative stress, and did not induce proinflammatory proteins.
authors.affiliation: IONTOX, LLC, Kalamazoo, MI, United States. Electronic address: jmckim@iontox.com.
authors.forename: James M
authors.initials: JM
authors.lastname: McKim
authors.affiliation: IONTOX, LLC, Kalamazoo, MI, United States.
authors.forename: Heidi
authors.initials: H
authors.lastname: Baas
authors.affiliation: IONTOX, LLC, Kalamazoo, MI, United States.
authors.forename: Gabriel P
authors.initials: GP
authors.lastname: Rice
authors.affiliation: Cyprotex, Kalamazoo, MI, United States.
authors.forename: Jamin A
authors.initials: JA
authors.lastname: Willoughby
authors.affiliation: TOXpertise, LLC, Princeton, NJ, United States.
authors.forename: Myra L
authors.initials: ML
authors.lastname: Weiner
authors.affiliation: Celtic Colloids, Inc., Topsham, ME, United States.
authors.forename: William
authors.initials: W
authors.lastname: Blakemore
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002351:Carrageenan / Q000494:pharmacology*; D002463:Cell Membrane Permeability / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D007414:Intestinal Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008113:Liver Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D012333:RNA, Messenger; D002351:Carrageenan
keywords: Carrageenan; Inflammation; Intestine; In vitro; Liver; Toll-like receptor 4