Apolipoprotein E COG 133 mimetic peptide improves 5-fluorouracil-induced intestinal mucositis

Abstract

BackgroundIntestinal mucositis is one of the major troublesome side effects of anticancer chemotherapy leading to poor patient compliance. In this study we addressed the role of the novel apolipoprotein E (ApoE) COG 133 mimetic peptide in 5-fluorouracil (5-FU)-challenged Swiss mice and IEC-6 cell monolayers. Experiments were also conducted in C57BL6J ApoE knock-out mice to assess the effects of apoE peptide treatment.MethodsExperimental groups were as follows: unchallenged controls, 5-FU-challenged mice (450 mg/kg, i.p) with or without the ApoE peptide (0.3, 1, and 3 μM, given twice daily i.p. for 4 days). Mice were sacrificed 3 days after 5-FU challenge. Proximal small intestinal samples were harvested for molecular biology and histological processing. We conducted ELISA assays and RT-PCR to target IL-1β, TNF-α, IL-10, iNOS, and myeloperoxidase (MPO) to assess intestinal inflammation. Cell death and NF-κB assays were also conducted in apoE knock-out mice. In our in vitro models, IEC-6 cells were exposed to 1 mM of 5-FU in glutamine free media with or without the ApoE peptide (0.02, 0.2, 2, 5, 10, and 20 μM). We investigated IEC-6 cell proliferation and migration, 24 h after the 5-FU challenge. Additionally, apoptotic IEC-6 cells were measured by Tunel and flow cytometry. Equimolar doses of the ApoA-I (D4-F) peptide were also used in some experiments for comparative studies.ResultsVillus blunting and heavy inflammatory infiltrates were seen in the 5-FU-challenged group, findings that were partially ameliorated by the ApoE peptide. We found increased intestinal MPO and pro-inflammatory IL-1β and TNF-α levels, and TNF-α and iNOS transcripts, and reduction of IL-10 following 5-FU treatment, each of which were partially abrogated by the peptide. Improvements were also found in IEC-6 cell apoptosis and migration following ApoE and D-4F treatment.ConclusionAltogether, these findings suggest that the novel ApoE COG 133 mimetic peptide can reduce 5-FU-induced intestinal changes and potentially benefit mucositis.

L-Arginine Pretreatment Reduces Intestinal Mucositis as Induced by 5-FU in Mice

“…Neutrophil infiltration has been reported in several studies that assessed mucositis (24,32,33). We observed intermediate MPO activity in animals receiving L-arginine.…”

Alanyl-glutamine attenuates 5-fluorouracil-induced intestinal mucositis in apolipoprotein E-deficient mice

“…We have also confirmed a healing effect of the apoE COG133 in the rat jejunal IEC-6 wound model after 5-FU exposure (15). Ala-Gln is a glutamine compound with increased solubility and stability.…”

Inhibition of Interleukin-10 Signaling Induces Microbiota-dependent Chronic Colitis in Apolipoprotein E Deficient Mice

“…In a study by Singh et al (62), the group further demonstrated the protective efficacy of ApoE mimetic peptide COG112 in inhibiting inflammatory responses in murine models of Citrobacter rodentium- induced and DSS-induced colitis. In other studies with mice, the ApoE mimetic peptide COG133 was shown to be equally protective against 5-fluorouracil-induced intestinal mucositis (63) and mitigating the inflammatory response to LPS challenge (64). In this regard, our present findings further highlights the importance of ApoE in maintaining gut homeostasis and that perhaps ApoE mimetic peptides would present a potential therapeutics to correct ApoE deficiency-associated microbiotal dysbiosis that predisposes colitis.…”