title: ERK pathway and sheddases play an essential role in ethanol-induced CX3CL1 release in pancreatic stellate cells.
abstract: The clinical course of chronic pancreatitis (CP) worsens with drinking, and pancreatic stellate cells (PSCs) have an important role in the pathogenesis of alcoholic CP. Chemokines recruit inflammatory cells, resulting in chronic pancreatic inflammation. Although serum levels of fractalkine (CX3CL1) are significantly elevated in patients with alcoholic CP, the mechanism of this elevation remains unclear. This study aims to determine the effects of cytokines, pathogen-associated molecular patterns (PAMPs), and ethanol and its metabolites on CX3CL1 secretion by PSCs. Male Wistar/Bonn Kobori (WBN/Kob) rats aged 15 to 20 weeks were used as rodent models of CP in vivo. PSCs were isolated from 6-week-old male Wistar rats. The effects of cytokines, PAMPs, and ethanol and its metabolites on chemokine production and activation of signaling pathways in PSCs in vitro were examined by real-time reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and enzyme-linked immunosorbent assay. Expression of CX3CL1 and matrix metalloprotease (MMP)-2 was increased in the pancreas of WBN/Kob rats. The rat PSCs expressed CX3CL1, MMP-2, and a disintegrin and metalloprotease domain (ADAM) 17. Cytokines and PAMPs induced CX3CL1 release and activated extracellular signal-regulated kinase (ERK), MMP-9, and ADAM17. CX3CL1 release was suppressed by specific inhibitors of ERK, MMP, and ADAM, and ERK was associated with CX3CL1 transcription. Ethanol and phorbol myristate acetate synergistically increased CX3CL1 release. Real-time PCR and western blotting confirmed the synergistic activation of ERK and ADAM17. Ethanol synergistically increased CX3CL1 release via ERK and ADAM17 activation in PSCs. In conclusion, we demonstrated for the first time that ethanol synergistically increased CX3CL1 release from PSCs at least in part through activation of ERK mitogen-activated protein kinase and ADAM17. This might be one of the mechanisms of serum CX3CL1 elevation and disease progression in patients with alcoholic CP.
authors.affiliation: Department of Medicine and Bioregulatory Science, Kyushu University, Fukuoka, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Uchida
authors.forename: Tetsuhide
authors.initials: T
authors.lastname: Ito
authors.forename: Taichi
authors.initials: T
authors.lastname: Nakamura
authors.forename: Hisato
authors.initials: H
authors.lastname: Igarashi
authors.forename: Takamasa
authors.initials: T
authors.lastname: Oono
authors.forename: Nao
authors.initials: N
authors.lastname: Fujimori
authors.forename: Ken
authors.initials: K
authors.lastname: Kawabe
authors.forename: Koichi
authors.initials: K
authors.lastname: Suzuki
authors.forename: Robert T
authors.initials: RT
authors.lastname: Jensen
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Takayanagi
mesh_terms: D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism; D000072198:ADAM17 Protein; D000818:Animals; D054428:Chemokine CX3CL1 / Q000235:genetics / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism; D000431:Ethanol / Q000494:pharmacology*; D006651:Histocytochemistry; D020935:MAP Kinase Signaling System / Q000187:drug effects* / Q000502:physiology; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D058954:Pancreatic Stellate Cells / Q000187:drug effects* / Q000201:enzymology* / Q000378:metabolism; D050500:Pancreatitis, Chronic / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D054428:Chemokine CX3CL1; C515540:Cx3cl1 protein, rat; D016207:Cytokines; D000431:Ethanol; D051722:ADAM Proteins; D020778:Matrix Metalloproteinase 2; D000072198:ADAM17 Protein; C000606464:Adam17 protein, rat