Induction of CXCL1 by extracellular matrix and autocrine enhancement by interleukin-1 in rat pancreatic beta-cells.
As we showed previously, the extracellular matrix (ECM) derived from rat bladder carcinoma cells (804G-ECM) has positive effects on rat primary beta-cell function and survival in vitro. The aim of this study was to define beta-cell genes induced by this ECM with a specific focus on cytokines. Analysis of differential gene expression by oligonucleotide microarrays, RT-PCR, and in situ hybridization was performed to identify cytokine mRNA induced by this matrix. Four cytokines were overexpressed on 804G-ECM compared with poly-L-lysine: C-X-C motif ligand 1 (CXCL1), CXCL2, interferon-inducible protein-10, and IL-1beta. A time-course experiment indicated that maximal induction by 804G-ECM of CXCL1/2 and interferon-inducible protein-10 occurred at 4 h. Stimulation of CXCL1 release by beta-cells on 804G-ECM was confirmed at the protein level. Moreover, secreted CXCL1 was shown to be functionally active by attracting rat granulocytes. Preventing the interaction of beta1 integrins and laminin-5 (a major component of 804G-ECM) with specific antibodies resulted in a 40-50% inhibition of CXCL1 expression. Using the nuclear factor-kappaB pathway inhibitor Bay 11-7082 it is demonstrated that CXCL1 expression and secretion are dependent on nuclear factor-kappaB activation. IL-1 secreted by beta-cells plated on 804G-ECM was found to be a key soluble mediator because treatment of cells with the IL-1 receptor antagonist significantly reduced both CXCL1 gene expression and secretion. It is concluded that ECM induces expression of cytokines including CXCL1 with amplification by IL-1 acting via a positive autocrine feedback loop.
Ribaux
Pascale
P
Department of Genetic Medicine and Development, University Medical Center, 1211, Geneva-4, Switzerland. Pascale.Ribaux@medecine.unige.ch
Ehses
Jan A
JA
Lin-Marq
Nathalie
N
Carrozzino
Fabio
F
Böni-Schnetzler
Marianne
M
Hammar
Eva
E
Irminger
Jean-Claude
JC
Donath
Marc Y
MY
Halban
Philippe A
PA
D000818:Animals; D019898:Autocrine Communication / Q000187:drug effects*; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D054360:Chemokine CXCL1 / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D017077:Culture Media, Conditioned / Q000494:pharmacology; D016207:Cytokines / Q000235:genetics; D005109:Extracellular Matrix / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006098:Granulocytes / Q000166:cytology / Q000187:drug effects; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D008954:Models, Biological; D051381:Rats; D017208:Rats, Wistar
D054360:Chemokine CXCL1; D017077:Culture Media, Conditioned; C513297:Cxcl1 protein, rat; D016207:Cytokines; D007375:Interleukin-1