Lima-Júnior RCP, Freitas HC, Wong DVT, Wanderley CWS, Nunes LG, Leite LL, Miranda SP, Souza MHLP, Brito GAC, Magalhães PJC, Teixeira MM, Cunha FQ, Ribeiro RA. Targeted inhibition of IL-18 attenuates irinotecan-induced intestinal mucositis in mice.
Br J Pharmacol 2014;
171:2335-50. [PMID:
24428790 DOI:
10.1111/bph.12584]
[Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 12/08/2013] [Accepted: 12/26/2013] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE
Intestinal mucositis is a common side-effect of irinotecan-based cancer chemotherapy regimens. This mucositis is associated with cytokine activation and NO synthesis. Production of IL-18 is up-regulated in patients suffering from inflammatory bowel disease. Therefore, we have investigated the role of IL-18 in the pathogenesis of irinotecan-induced intestinal mucositis.
EXPERIMENTAL APPROACH
Wild type (WT), IL-18 or caspase-1 knockout mice were treated with either saline or irinotecan (60 mg·kg⁻¹ per 4 days, i.p.) or the IL-18 binding protein (IL-18bp, 10 mg·kg⁻¹) before irinotecan. On day 5, diarrhoea was monitored and proximal intestinal strips were obtained for histopathology, in vitro gut contractility, myeloperoxidase (MPO) and inducible NOS (iNOS) activity, and detection of IL-18 expression.
KEY RESULTS
Irinotecan induced severe diarrhoea accompanied by intestinal injury (villi shortening and increased crypt depth). Additionally, irinotecan treatment increased MPO and iNOS activity, iNOS immunostaining and IL-18 expression in WT mice compared with saline treatment. The IL-18 production was associated with macrophages. In vitro, intestinal smooth muscle strips were hyperresponsive to ACh after irinotecan treatment. Increases in MPO and iNOS activity, intestinal contractility and diarrhoea were prevented in caspase-1 knockout and IL-18 knockout mice, and in IL-18bp-treated WT mice. Furthermore, the Survival of irinotecan-treated mice was increased and iNOS immunoexpression and IL-18 production prevented in IL-18 knockout mice.
CONCLUSIONS AND IMPLICATIONS
Targeting IL-18 function may be a promising therapeutic approach to decreasing the severity of intestinal mucositis during irinotecan treatment regimens.
Collapse