Mucositis resulting from cancer chemotherapy is characterized by intestinal inflammation and ulceration. Previously, emu oil (EO) improved intestinal architecture (Br J Nutr, 2010) in a rat model of chemotherapy-induced mucositis. We investigated EO for its further potential to promote intestinal repair in this mucositis model. Female Dark Agouti rats (n = 8/group) were gavaged with water, olive oil (OO) or EO once daily (1 mL), injected with 5-fluorouracil (5-FU) or saline on day 5 and euthanized on day 8, 9, 10 or 11. Intestinal villus height (VH) and crypt depth (CD), neutral mucin-secreting goblet cell (GC) count, myeloperoxidase (MPO) activity and selected cytokines were quantified; P < 0.05 was considered significant. In 5-FU-injected rats, only EO administration significantly increased VH in the ileum (day 8), jejunum and jejunum-ileum junction (days 8 and 9) compared to 5-FU controls (P < 0.05). GC count was significantly reduced by 5-FU (jejunum: days 8 and 9; ileum: day 8; P < 0.05) and EO increased ileal GC on days 10 and 11 compared to 5-FU controls. MPO activity was significantly increased in jejunum (days 8 and 9) and ileum (day 8) following 5-FU injection, compared to normal controls (P < 0.05). Both EO and OO significantly reduced jejunal MPO on days 8 and 9; however, only EO decreased ileal MPO on day 8. Cytokine levels were not significantly affected by either oil or 5-FU administration at the day 8 time point. Promotion of repair from injury could represent a new mechanism of action for EO, suggesting potential as an adjunct to conventional treatment approaches for cancer management.

There is an acute need for the development of effective therapies for mucositis, a debilitating side effect of cancer chemotherapy. Iberogast ® is a herbal extract reported to possess anti-inflammatory properties. We investigated Iberogast ® for its potential to reduce the severity of 5-Fluorouracil (FU)-induced mucositis in rats. Rats were allocated to three treatment groups (n = 8) and gavaged daily with a 10% solution of Iberogast ® or water from day 0 to day 8. Rats were injected intraperitoneally with 5-FU (150 mg/kg) or saline on day 6, and killed after 72 h. In vivo and in vitro sucrase activity was assessed by 13 C-sucrose breath test (SBT) and sucrase assay respectively. Intestinal disease severity was determined by histological assessment of villus height and crypt depth. Significant increases in villus height (277 ± 9 μm) and crypt depth (67 ± 3 μm) were observed in 5-FU + Iberogast ® -treated rats compared with 5-FU + Water (224 ± 13 μm and 48 ± 2 μm respectively; p < 0.05). Sucrase activity was significantly reduced in all 5-FU groups compared to control. Significant reductions in SBT and sucrase activity were observed in all 5-FU groups compared with Saline + Water controls (p < 0.05). We conclude that although Iberogast ® partially improved the histopathological features of 5-FU induced mucositis, it conferred no significant protection as indicated by the assessed endpoints.

Behavioural indicators of affective state, including burrowing, clinical scores and the Mouse Grimace Score have not yet been validated in mouse models of chronic gastrointestinal disease. Additionally, a comparison of these methods has not been characterised. This study aimed to determine which behavioural assessment was the optimal indicator of disease, evidenced by correlation with clinically-assessed measures, in an azoxymethane (AOM)/dextran sulphate sodium (DSS) mouse model of colitis-associated colorectal cancer. C57BL/6 mice were allocated to four groups (n = 10/group); 1) saline control, 2) saline+buprenorphine, 3) AOM+DSS+water, 4) AOM+DSS+buprenorphine. Mice were gavaged thrice weekly with water or buprenorphine (0.5mg/kg; 80μL) for 9 weeks. Disease activity index (DAI) was measured daily; burrowing and grimace analyses occurred on days-1, 5, 19, 26, 40, 47 and 61. Colonoscopies were performed on days 20, 41 and 62. All animals were euthanized on day 63. Burrowing activity and retrospective grimace analyses were unaffected (P>0.05), whilst DAI was significantly increased (P<0.05) in mice with colitis-associated colorectal cancer compared to normal controls. In addition, DAI was positively correlated with colonoscopically-assessed severity and tumour number (P<0.05). We conclude that traditional measures of DAI or clinical scoring provide the most reliable assessment of wellbeing in mice with colitis-associated colorectal cancer.

Chemotherapy-induced mucositis is characterized by inflammation and ulcerating lesions lining the alimentary tract. Emu Oil and Lyprinol™ have independently demonstrated their therapeutic potential in intestinal inflammatory disorders, including mucositis. We investigated Emu Oil and Lyprinol™ in combination for their further potential to alleviate chemotherapy-induced mucositis in rats. Rats were gavaged with (1 ml) water, Olive Oil, Emu Oil + Olive Oil, Lyprinol™ + Olive Oil or Emu Oil + Lyprinol™ from Days 0 to 7, injected with saline (control) or 5-Fluorouracil (5-FU) on Day 5 and euthanized on Day 8. Myeloperoxidase (MPO) activity (indicative of acute inflammation), histological severity scores, and intestinal architecture were quantified. Myeloperoxidase activity was significantly increased in the jejunum and ileum following 5-FU, compared to saline controls. Both Olive Oil and Emu Oil + Lyprinol™ significantly reduced jejunal MPO levels (1.8-fold and 1.7-fold, respectively), whereas only Emu Oil + Lyprinol™ significantly decreased ileal MPO levels, relative to 5-FU controls. All oil treatments decreased histological severity scores in the jejunum and ileum, and normalized crypt depth in the mid small intestine, relative to 5-FU controls. Emu Oil combined with Lyprinol™ partially reduced acute small intestinal inflammation. Isolating bioactive constituents of these naturally sourced oils could provide a more targeted strategy to protect against intestinal mucositis.

Emu Oil improved clinical indicators and reduced severity of colitis-associated colorectal cancer, suggesting therapeutic potential in colitis management.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by cytokine driven inflammation that disrupts the mucosa and impedes intestinal structure and functions. Flightless I (Flii) is an immuno-modulatory protein is a member of the gelsolin family of actin-remodelling proteins that regulates cellular and inflammatory processes critical in tissue repair. Here we investigated its involvement in UC and show that Flii is significantly elevated in colonic tissues of patients with inflammatory bowel disease. Using an acute murine model of colitis, we characterised the contribution of Flii to UC using mice with low ( Flii +/− ), normal ( Flii +/+ ) and high Flii ( Flii Tg/Tg ). High levels of Flii resulted in significantly elevated disease severity index scores, increased rectal bleeding and degree of colon shortening whereas, low Flii expression decreased disease severity, reduced tissue inflammation and improved clinical indicators of UC. Mice with high levels of Flii had significantly increased histological disease severity and elevated mucosal damage with significantly increased inflammatory cell infiltrate and significantly higher levels of TNF-α, IFN-γ, IL-5 and IL-13 pro-inflammatory cytokines. Additionally, Flii overexpression resulted in decreased β-catenin levels, inhibited Wnt/β-catenin signalling and impaired regeneration of colonic crypts. These studies suggest that high levels of Flii, as is observed in patients with UC, may adversely affect mucosal healing via mechanisms involving Th 1 and Th 2 mediated tissue inflammation and Wnt/β-catenin signalling pathway.

No abstract

Crohn’s disease is a severe, incurable inflammatory bowel disease. Orally administered emu oil has demonstrated anti-inflammatory properties in previous models of gastrointestinal disease. We aimed to determine whether orally administered emu oil could attenuate disease in a mouse model of Crohn’s-like colitis. Female ARC(s) mice (CD-1 equivalent, n = 10/group) were intra-rectally administered water (120 μL) or trinitrobenzene sulfonic acid (TNBS; 3 mg in 50% ethanol; 120 μL bolus) on day 0. Mice were orally administered water (80 μL) or emu oil (80 μL or 160 μL) daily for five days and euthanized on day six. Bodyweight and disease activity were recorded daily. Colonoscopy, burrowing activity, facial grimace, histological parameters (damage severity, small intestinal villus height/crypt depth and colonic crypt depth), myeloperoxidase activity and intestinal permeability were assessed. P < 0.05 was considered statistically significant. TNBS decreased bodyweight (days 1, 2, 4; P < 0.05) and increased disease activity (days 1–6; P < 0.01), compared to normal controls. Emu oil (80 μL) attenuated disease activity on days 5–6 ( P < 0.05), although bodyweight loss was not significantly impacted ( P > 0.05). Facial grimace and colonoscopy scores were significantly increased in TNBS-control mice; effects attenuated by both volumes of emu oil ( P < 0.001). TNBS increased histological damage severity compared to normal controls ( P < 0.05); an effect attenuated by 80 μL emu oil (proximal and distal colon; P < 0.05) and 160 μL emu oil (distal colon; P < 0.01). In the ileum, villus height and crypt depth were unaffected by TNBS or emu oil treatment compared to normal ( P > 0.05). TNBS-induced distal colonic crypt lengthening was unaffected following emu oil administration ( P > 0.05). Remaining parameters, including burrowing, myeloperoxidase activity and intestinal permeability, were unchanged across all treatment groups ( P > 0.05). In normal mice, emu oil treatment did not significantly impact any parameter compared to normal controls. In conclusion, emu oil reduced overall disease severity and facial grimace scores in TNBS mice. These results suggest therapeutic potential for orally administered emu oil in the management of Crohn’s disease. Impact statement The submitted work details novel research to contribute to the field of inflammatory bowel diseases, specifically Crohn’s disease and alternative therapies. This work is important as current therapies for Crohn’s disease are variably effective and often significantly compromise patient quality of life. Emu oil, used in the current study, has the potential to alleviate disease severity and promote intestinal repair in a mouse model of Crohn’s-like colitis. The new findings from this manuscript, whereby emu oil attenuated disease severity from clinical scores and colonoscopy results, add to the literature of inflammatory bowel disease mouse models and support the therapeutic potential of emu oil. This research may advance the progression to clinical trials and ultimately the commercialization of emu oil as an adjunctive or alternative therapy for the detrimental inflammatory bowel diseases.