title: Alpha-Melanocyte Stimulating Hormone Protects against Cytokine-Induced Barrier Damage in Caco-2 Intestinal Epithelial Monolayers.
abstract: Alpha-melanocyte-stimulating hormone (α-MSH) is a potent anti-inflammatory peptide with cytoprotective effect in various tissues. The present investigation demonstrates the ability of α-MSH to interact with intestinal epithelial cell monolayers and mitigate inflammatory processes of the epithelial barrier. The protective effect of α-MSH was studied on Caco-2 human intestinal epithelial monolayers, which were disrupted by exposure to tumor necrosis factor-α and interleukin-1β. The barrier integrity was assessed by measuring transepithelial electric resistance (TEER) and permeability for marker molecules. Caco-2 monolayers were evaluated by immunohistochemistry for expression of melanocortin-1 receptor and tight junction proteins ZO-1 and claudin-4. The activation of nuclear factor kappa beta (NF-κB) was detected by fluorescence microscopy and inflammatory cytokine expression was assessed by flow cytometric bead array cytokine assay. Exposure of Caco-2 monolayers to proinflammatory cytokines lowered TEER and increased permeability for fluorescein and albumin, which was accompanied by changes in ZO-1 and claudin-4 immunostaining. α-MSH was able to prevent inflammation-associated decrease of TEER in a dose-dependent manner and reduce the increased permeability for paracellular marker fluorescein. Further immunohistochemistry analysis revealed proinflammatory cytokine induced translocation of the NF-κB p65 subunit into Caco-2 cell nuclei, which was inhibited by α-MSH. As a result the IL-6 and IL-8 production of Caco-2 monolayers were also decreased with different patterns by the addition of α-MSH to the culture medium. In conclusion, Caco-2 cells showed a positive immunostaining for melanocortin-1 receptor and α-MSH protected Caco-2 cells against inflammatory barrier dysfunction and inflammatory activation induced by tumor necrosis factor-α and interleukin-1β cytokines.
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Judit
authors.initials: J
authors.lastname: Váradi
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Harazin
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Ferenc
authors.initials: F
authors.lastname: Fenyvesi
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Katalin
authors.initials: K
authors.lastname: Réti-Nagy
authors.affiliation: Department of Immunology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
authors.forename: Péter
authors.initials: P
authors.lastname: Gogolák
authors.affiliation: Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Vámosi
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Ildikó
authors.initials: I
authors.lastname: Bácskay
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Pálma
authors.initials: P
authors.lastname: Fehér
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Ujhelyi
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Gábor
authors.initials: G
authors.lastname: Vasvári
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Eszter
authors.initials: E
authors.lastname: Róka
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.|Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: David
authors.initials: D
authors.lastname: Haines
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Mária A
authors.initials: MA
authors.lastname: Deli
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary.
authors.forename: Miklós
authors.initials: M
authors.lastname: Vecsernyés
mesh_terms: D018938:Caco-2 Cells; D062506:Claudin-4 / Q000378:metabolism; D019610:Cytoprotection / Q000187:drug effects; D017097:Electric Impedance; D006801:Humans; D007249:Inflammation / Q000517:prevention & control; D053583:Interleukin-1beta / Q000008:administration & dosage; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000293:injuries* / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D010539:Permeability / Q000187:drug effects; D044102:Receptor, Melanocortin, Type 1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage; D062826:Zonula Occludens-1 Protein / Q000378:metabolism; D000521:alpha-MSH / Q000494:pharmacology*
chemical_list: C568157:CLDN4 protein, human; C508606:CXCL8 protein, human; D062506:Claudin-4; C508600:IL6 protein, human; D053583:Interleukin-1beta; D015850:Interleukin-6; D016209:Interleukin-8; D016328:NF-kappa B; D044102:Receptor, Melanocortin, Type 1; C569042:TJP1 protein, human; D014409:Tumor Necrosis Factor-alpha; D062826:Zonula Occludens-1 Protein; D000521:alpha-MSH