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Objectives: Ulcerative colitis is an incurable inflammatory bowel disease that increases the risk of colorectal cancer (CRC). 5-Fluorouracil (5-FU) is the predominant chemotherapy for CRC patients; however, undesirable side-effects, including mucositis, are common. This study utilised 5-FU-treatment in a model of colitis-associated CRC to develop a pre-clinical setting of intestinal mucositis coincident with manifestation of CRC. Materials/methods: On day 0, female C57BL/6 mice ( n  = 10/group); (1) saline control, (2) AOM/DSS control, or (3) AOM/DSS + 5-FU were injected with saline or AOM (i.p; 7.4 mg/kg). Groups 2 and 3 underwent cycles of seven days 2%w/v DSS followed by 14 days plain water. After three cycles, 5-FU was administered weekly (i.p; 75 mg/kg) to group 3 for five weeks. Clinical indicators were measured daily and colonoscopy performed at four time-points. Mice were euthanized at 13 weeks (day 91). Intestinal sections were collected for histological and biochemical analyses. p  < .05 was considered significant. Results: AOM/DSS resulted in bodyweight loss, increased disease activity index, colitis-severity and tumour number compared to saline controls ( p  < .05). 5-FU-treatment in AOM/DSS mice decreased bodyweight and disease activity index at selected time-points compared to AOM/DSS controls ( p  < .05). 5-FU did not impact colitis-severity or overall tumour burden; although, resulted in fewer small tumours compared to AOM/DSS controls (<2mm; p  < .05). AOM/DSS increased histological severity scores in intestinal sections ( p  < .05), however, 5-FU-treatment did not further increase histologically-assessed disease severity ( p  > .05). Conclusion: Weekly 5-FU administration at a dose of 75 mg/kg was insufficient to reduce overall tumour burden or induce intestinal mucositis in the AOM/DSS mouse model.

Background: Prebiotics selectively stimulate the growth of beneficial bacteria within the gastrointestinal tract, and have been investigated in human and animal studies for their capacity to improve intestinal health., Objective: We investigated the prebiotics fructo-oligosaccharide (FOS), galacto-oligosaccharide (GOS), and mannan-oligosaccharide (MOS) for their potential to alleviate intestinal damage in rats., Methods: Female Dark Agouti rats (6-8 wk old, 110-150 g) were allocated to 1 of the following treatment groups (n = 8/group): saline/water, saline/FOS, saline/GOS, saline/MOS, 5-fluorouracil (5FU)/water, 5FU/FOS, 5FU/GOS, and 5FU/MOS. Rats were pretreated with either 5% GOS, MOS, or FOS or vehicle (water) from day -12 to day 0. On day 0, rats received a single intraperitoneal injection of saline or 5FU. Metabolic data were recorded daily and all rats were killed on day 3. Histopathology was quantified in hematoxylin and eosin-stained sections. Intestinal sucrase and myeloperoxidase activity were quantified by biochemical assay. Fecal SCFAs-acetic, propionic, and butyric acid-were also measured. Statistical analysis was by repeated-measures, 2-factor ANOVA or Kruskal-Wallis and Mann-Whitney U test; P < 0.05 was considered statistically significant., Results: Body weight was significantly decreased in all treatment groups after 5FU injection, with no change in body weight observed in any prebiotic treatment group. Total food intake was lower by ≥7% in the GOS treatment group pre-5FU than in all other groups (P < 0.05). Ileal villus height was 18% higher in GOS-treated rats pre-5FU than in respective water controls (P < 0.05). Jejunal and ileal villus height and crypt depth were significantly decreased in all treatment groups after 5FU injection, with no prebiotic effect observed. SCFAs were differentially increased in prebiotic treatment groups compared with water-only controls (P < 0.05)., Conclusions: FOS, GOS, and MOS have differential effects in modifying small intestinal pathology and SCFA profiles in rats with healthy and damaged small intestinal mucosa., (Copyright © American Society for Nutrition 2019.)

Chemotherapy-induced mucositis is an extremely painful condition that occurs in 40-60% of patients undergoing chemotherapy. As mucositis currently has no effective treatment, and due to the self-limiting nature of the condition, the major treatment aims are to manage symptoms and limit pain with significance placed on improving patient quality of life. Rodent models are frequently used in mucositis research. These investigations typically assess pathological outcomes, yet fail to include a measure of affective state; the key therapeutic goal. Assessment of cognitive biases is a novel approach to determining the affective state of animals. Consequently, this study aimed to validate a cognitive bias test through a judgement bias paradigm to measure affective state in a rat model of chemotherapy-induced intestinal mucositis. Rats with intestinal mucositis demonstrated a negative affective state, which was partially ameliorated by analgesic administration, whilst healthy rats showed an optimistic response. This study concluded that the judgement bias test was able to evaluate the emotional state of rats with chemotherapy-induced mucositis. These findings provide a foundation for future refinement to the experimental design associated with the animal model that will expedite successful transitioning of novel therapeutics to clinical practice, and also improve humane endpoint implementation.

Faecalibacterium prausnitzii (Fp) and Escherichia coli Nissle 1917 (EcN) are probiotics, which have been reported to ameliorate certain gastrointestinal disorders. We evaluated the effects of supernatants (SN) derived from Fp and EcN on 5-fluorouracil (5-FU)-treated intestinal cells and in a rat model of mucositis. In vitro: IEC-6, Caco-2, and T-84 cells were analyzed for viability and monolayer permeability. In vivo: Female dark agouti rats were gavaged with Fp or EcN SN and injected intraperitoneally with saline (control) or 5-FU to induce mucositis. Rats were euthanized and intestinal tissues collected for myeloperoxidase assay and histological analyses. In vitro: Caco-2 cell viability was further reduced when treated with Fp SN + 5-FU compared to 5-FU controls. In both Caco-2 and T-84 cells, Fp SN partially prevented the decrease in transepithelial electrical resistance (TER) caused by 5-FU administration. In vivo: 5-FU-injected rats administered Fp SN or EcN SN partly prevented body weight loss and normalized water intake compared to 5-FU controls. These results suggest a growth inhibitory mechanism of Fp SN action on transformed epithelial cells that could be mediated by effects on tight junctions. Factors derived from Fp SN and EcN SN could have a role in reducing the severity of intestinal mucositis.

Aim: To investigate the effects of orally gavaged aqueous rhubarb extract (RE) on 5-fluorouracil (5-FU)-induced intestinal mucositis in rats., Methods: Female Dark Agouti rats ( n = 8/group) were gavaged daily (1 mL) with water, high-dose RE (HDR; 200 mg/kg) or low-dose RE (LDR; 20mg/kg) for eight days. Intestinal mucositis was induced (day 5) with 5-FU (150 mg/kg) via intraperitoneal injection. Intestinal tissue samples were collected for myeloperoxidase (MPO) activity and histological examination. Xenopus oocytes expressing aquaporin 4 water channels were prepared to examine the effect of aqueous RE on cell volume, indicating a potential mechanism responsible for modulating net fluid absorption and secretion in the gastrointestinal tract. Statistical significance was assumed at P < 0.05 by one-way ANOVA., Results: Bodyweight was significantly reduced in rats administered 5-FU compared to healthy controls ( P < 0.01). Rats administered 5-FU significantly increased intestinal MPO levels (≥ 307%; P < 0.001), compared to healthy controls. However, LDR attenuated this effect in 5-FU treated rats, significantly decreasing ileal MPO activity (by 45%; P < 0.05), as compared to 5-FU controls. 5-FU significantly reduced intestinal mucosal thickness (by ≥ 29% P < 0.001) as compared to healthy controls. LDR significantly increased ileal mucosal thickness in 5-FU treated rats (19%; P < 0.05) relative to 5-FU controls. In xenopus oocytes expressing AQP4 water channels, RE selectively blocked water influx into the cell, induced by a decrease in external osmotic pressure. As water efflux was unaltered by the presence of extracellular RE, the directional flow of water across the epithelial barrier, in the presence of extracellular RE, indicated that RE may alleviate water loss across the epithelial barrier and promote intestinal health in chemotherapy-induced intestinal mucositis., Conclusion: In summary, low dose RE improves selected parameters of mucosal integrity and reduces ileal inflammation, manifesting from 5-FU-induced intestinal mucositis., Competing Interests: Conflict-of-interest statement: The authors wish to acknowledge no conflict of interest.

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.

Chemotherapy-induced intestinal mucositis is characterized by pain and a pro-inflammatory tissue response. Rat models are frequently used in mucositis disease investigations yet little is known about the presence of pain in these animals, the ability of analgesics to ameliorate the condition, or the effect that analgesic administration may have on study outcomes. This study investigated different classes of analgesics with the aim of determining their analgesic effects and impact on research outcomes of interest in a rat model of mucositis. Female DA rats were allocated to 8 groups to include saline and chemotherapy controls (n = 8). Analgesics included opioid derivatives (buprenorphine; 0.05mg/kg and tramadol 12.5mg/kg) and NSAID (carprofen; 15mg/kg) in combination with either saline or 5-Fluorouracil (5-FU; 150mg/kg). Research outcome measures included daily clinical parameters, pain score and gut histology. Myeloperoxidase assay was performed to determine gut inflammation. At the dosages employed, all agents had an analgesic effect based on behavioural pain scores. Jejunal myeloperoxidase activity was significantly reduced by buprenorphine and tramadol in comparison to 5-FU control animals (53%, p = 0.0004 and 58%, p = 0.0001). Carprofen had no ameliorating effect on myeloperoxidase levels. None of the agents reduced the histological damage caused by 5-FU administration although tramadol tended to increase villus length even when administered to healthy animals. These data provide evidence that carprofen offers potential as an analgesic in this animal model due to its pain-relieving efficacy and minimal effect on measured parameters. This study also supports further investigation into the mechanism and utility of opioid agents in the treatment of chemotherapy-induced mucositis.

Chemotherapy-induced mucositis is characterized by inflammation and ulceration of the intestinal mucosa, compromising intestinal function. Exogenous nucleotides have been reported to repair the mucosa. The nucleotide preparation, Nucleoforce F0328 (Nucleoforce), was investigated for its potential to ameliorate intestinal mucositis in rats. Female Dark Agouti rats (n = 8/group) were gavaged once daily with Nucleoforce (175 mg/kg) or water from Days 0 to 8 and injected (i.p.) with 5-fluorouracil (5-FU; 150 mg/kg) or saline on Day 5. Histological parameters (disease severity, crypt depth, and villus height measurements) and myeloperoxidase activity were quantified. P < 0.05 was considered significant. Jejunal and ileal histological disease severity scores were significantly increased by 5-FU, compared to normal controls (P < 0.05). Nucleoforce treatment in 5-FU-injected rats significantly reduced jejunal and ileal disease severity compared to 5-FU controls (P < 0.05). In 5-FU-injected rats, jejunal and ileal villus heights and crypt depths were significantly decreased compared to 5-FU controls, with no additional Nucleoforce effect (P > 0.05). Intestinal myeloperoxidase activity was significantly elevated by 5-FU (8.8-fold), compared to normal controls (P < 0.05), which was not normalized by Nucleoforce treatment (P > 0.05). Nucleoforce only partially improved parameters associated with experimentally-induced mucositis. Future studies could investigate increased concentrations, more frequent administration, or protective microencapsulation delivery methods, to increase bioavailability.

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.

Background: Mucositis is a debilitating intestinal side effect of chemotherapeutic regimens. Probiotics have been considered a possible preventative treatment for mucositis. Streptococcus thermophilus TH-4 (TH-4), a newly identified probiotic, has been shown to partially alleviate mucositis induced by administration of the antimetabolite chemotherapy drug, methotrexate in rats; likely mediated through a mechanism of folate production. However, its effects against other classes of chemotherapy drug have yet to be determined., Aims: The authors investigated the effects of TH-4 in a rat model of mucositis induced by the anthracycline chemotherapy drug, doxorubicin., Methods: Gastrointestinal damage was induced in female Dark Agouti rats (148.3 ± 1.5 g) by intraperitoneal injection of doxorubicin (20 mg/kg). Animals recieved a daily oral gavage of TH-4 at 10(9) cfu/ml or skim milk (vehicle) from days 0 to 8. At day 6, rats were injected with either saline or doxorubicin. At kill, small intestinal tissues were collected for determination of sucrase and myeloperoxidase (MPO) activities and histological assessment., Results: Body weight was significantly decreased by doxorubicin compared with normal controls (p < 0.05). Histological parameters, such as crypt depth and villus height, were also significantly decreased by doxorubicin. TH-4 partially prevented the loss of body weight induced by doxorubicin (2.3% compared with 4%), but provided no further therapeutic benefit., Conclusions: The minimal amelioration of doxorubicin-induced mucositis by TH-4 further supports folate production as a likely mechanism of TH-4 action against methotrexate-induced mucositis. Further studies into TH-4 are required to confirm its applicability to other conventional chemotherapy regimens.

The potential efficacy of a probiotic-based preventative strategy against intestinal mucositis has yet to be investigated in detail. We evaluated supernatants (SN) from Escherichia coli Nissle 1917 (EcN) and Lactobacillus rhamnosus GG (LGG) for their capacity to prevent 5-fluorouracil (5-FU)-induced damage to intestinal epithelial cells. A 5-day study was performed. IEC-6 cells were treated daily from days 0 to 3, with 1 mL of PBS (untreated control), de Man Rogosa Sharpe (MRS) broth, tryptone soy roth (TSB), LGG SN, or EcN SN. With the exception of the untreated control cells, all groups were treated with 5-FU (5 μM) for 24 h at day 3. Transepithelial electrical resistance (TEER) was determined on days 3, 4, and 5, while activation of caspases 3 and 7 was determined on days 4 and 5 to assess apoptosis. Pretreatment with LGG SN increased TEER (p < 0.05) compared to controls at day 3. 5-FU administration reduced TEER compared to untreated cells on days 4 and 5. Pretreatment with MRS, LGG SN, TSB, and EcN SN partially prevented the decrease in TEER induced by 5-FU on day 4, while EcN SN also improved TEER compared to its TSB vehicle control. These differences were also observed at day 5, along with significant improvements in TEER in cells treated with LGG and EcN SN compared to healthy controls. 5-FU increased caspase activity on days 4 and 5 compared to controls. At day 4, cells pretreated with MRS, TSB, LGG SN, or EcN SN all displayed reduced caspase activity compared to 5-FU controls, while both SN groups had significantly lower caspase activity than their respective vehicle controls. Caspase activity in cells pretreated with MRS, LGG SN, and EcN SN was also reduced at day 5, compared to 5-FU controls. We conclude that pretreatment with selected probiotic SN could prevent or inhibit enterocyte apoptosis and loss of intestinal barrier function induced by 5-FU, potentially forming the basis of a preventative treatment modality for mucositis.

Introduction: Pre-clinical studies have indicated that palifermin may be an effective treatment modality for intestinal mucositis, a debilitating complication of cancer chemotherapy. We determined whether palifermin was protective in rats with experimentally induced intestinal mucositis and the applicability of the sucrose breath test (SBT) to monitor palifermin for its efficacy as an anti-mucositis agent., Results: SBT values and sucrase activity were reduced in all 5-FU-treated groups compared with untreated controls (p < 0.05). At 72 h post 5-FU, sucrase activity was higher in rats treated with palifermin compared with 5-FU controls (p < 0.05). Jejunal and ileal villus heights were lower in all 5-FU groups compared with saline controls., Methods: Dark agouti rats (n = 10) were subcutaneously injected with palifermin or vehicle for 3 d after which they were injected with 5-fluorouracil (5-FU) and sacrificed after 72 h. The in vivo SBT and in vitro sucrase assay were used to evaluate small intestinal function and damage. Intestinal disease severity was determined by histological assessment of villus height and crypt depth., Conclusion: The SBT can monitor the ability of palifermin to modify the functional capacity of the small intestine in rats with intestinal mucositis. Further studies are indicated to investigate the prophylactic potential of palifermin against intestinal mucositis.

Preventative or adjunctive agents for the amelioration of small intestinal chemotherapy-induced mucositis are not currently available for clinical use. We have previously demonstrated that oral ingestion of Streptococcus thermophilus (TH-4) partially attenuated chemotherapy-induced mucositis in the rat. Here we assess the effects of TH-4 on small intestinal damage and tumor progression in tumor-bearing rats with experimentally-induced mucositis. Female Dark Agouti tumor-bearing (mammary adenocarcinoma) rats (n = 36; 139 ± 1 g) had small intestinal damage induced via the administration of methotrexate (MTX). Rats were administered MTX; (1.5 mg/kg intramuscular) or saline at 0 and 24 h; with daily gavage administration of TH-4 (109 cfu/mL) or skim milk from -48 to +96 h post-MTX. Rats were allocated to groups (n=9): saline control, TH-4 control, MTX control or TH-4+MTX. The non-invasive ( 13) C-sucrose breath test (SBT) was conducted prior to tumor inoculation, pre-MTX (-24 h) and prior to sacrifice (96 h) to monitor gut function. At sacrifice small intestinal segments were excised and assessed for sucrase and myeloperoxidase activity as well as histological damage. Irrespective of TH-4 treatment, MTX-treated rats had a significant decrease in bodyweight, SBT levels, sucrase and myeloperoxidase activity, and histological damage score (p < 0.05) compared to saline and TH-4 control rats. TH-4 treatment did not result in tumor progression (p > 0.05) but failed to alleviate mucositis indices. Although TH-4, at a dose of 109 cfu/mL, yielded neither protection nor amelioration of chemotherapy-induced mucositis, progression of mammary adenocarcinoma was unaffected.

Certain live bacteria have demonstrated preliminary indications of efficacy for the treatment of chemotherapy-induced intestinal mucositis. However, probiotic derived supernatants (SN) have yet to be investigated in the mucositis setting. We evaluated SN from Escherichia coli Nissle 1917 (EcN) and Lactobacillus fermentum BR11 (BR11) for their capacity to decrease 5-Fluorouracil (5-FU)-induced damage in vivo. Female Dark Agouti rats were gavaged with 1 mL of either SN or vehicle daily (days 0-8) and intraperitoneally injected with 5-FU (150 mg/kg) on day 5 to induce mucositis. On day 9, animals were culled and intestinal tissues collected. Significantly lower histological damage scores were apparent in the jejunum of 5-FU treated rats receiving SN compared to 5-FU controls. Myeloperoxidase levels in the jejunum of 5-FU treated rats were increased in vehicle and BR11 SN treatments compared to untreated controls, whereas no significant increase was observed after EcN SN treatment. 5-FU treatment significantly reduced villus height and crypt depth in the jejunum compared to normal controls; however no significant reduction in these parameters was observed in 5-FU treated rats receiving either SN. We conclude that bacterial SN, especially EcN, partially protect the intestine from 5-FU mucositis. Further studies are required to define specific mechanisms by which SN exert their beneficial effects.

Although chemotherapy remains the current best practice for the treatment of neoplasia, the severity of its associated side-effects continues to impact detrimentally on the quality of life. Mucositis can affect both the oral cavity and intestine, and represents one of the most common side-effects of chemotherapy. It is characterized by ulceration, inflammation, diarrhoea, and intense abdominal pain. Despite extensive research there remains no definitive therapy for mucositis. This may be due to the multiple factors which contribute to its pathogenesis, including up-regulation of pro-inflammatory cytokines, increased apoptosis of epithelial cells, alteration of the gastrointestinal microbiota, and damage to the epithelium. Although employed increasingly in other gastrointestinal disorders, probiotics are yet to be comprehensively investigated in the treatment or prevention of chemotherapy-induced mucositis. Probiotic-based therapies have been shown to exert beneficial effects, including modulation of the microbiota and inhibition of pro-inflammatory cytokines. This review outlines the current evidence supporting the use of probiotics in intestinal mucositis, and suggests further research directions for the future.

Mucositis resulting from cancer chemotherapy is a serious disorder of the alimentary tract. Emu oil has demonstrated anti-inflammatory properties in animal models of arthritis and wound healing; however, its effects on the intestine remain unknown. We investigated emu oil for its potential to decrease the severity of mucositis in a rat model. Female Dark Agouti rats (110-150 g) were orogastrically gavaged with emu oil (0.5 or 1 ml) or water (1 ml) for 5 d before intraperitoneal injection of 5-fluorouracil (5-FU, 150 mg/kg) or saline (control), and this was continued up to the day of sacrifice (48, 72 and 96 h post 5-FU administration). Histological (villus height, crypt depth (CD) and disease severity score) and biochemical (myeloperoxidase (MPO) activity) parameters were determined in intestinal tissues collected at sacrifice. Sucrase activity in vivo was quantified by the sucrose breath test. Activated neutrophil activity (MPO) in the ileum was significantly decreased by emu oil (0.5 ml, 451 (sem 168) U/g and 1 ml, 503 (sem 213) U/g) compared with 5-FU-treated controls (1724 (sem 431) U/g) 96 h post 5-FU administration. There were also significant increases in CD (152 (sem 8) microm) in the ileum of rats that received 1 ml emu oil at 96 h compared with 5-FU-treated controls (CD (106 (sem 12) microm)). Emu oil did not affect sucrase activity. Emu oil decreased acute ileal inflammation, and improved mucosal architecture in the intestine during recovery from chemotherapy in rats. Further studies investigating the potential benefits of emu oil as a nutritional supplement for the treatment of intestinal disorders are indicated.

Background: Chemotherapy-induced small intestinal mucositis is a debilitating side effect of cancer chemotherapy and currently there are no effective therapies. Zinc (Zn), an essential trace element required for normal growth and development and tissue repair processes, may be a potential treatment strategy. Zn induces metallothionein (MT) which has been shown to sequester free radicals. The aim of this study was to determine the capacity for dietary Zn supplementation to ameliorate methotrexate (MTX)-induced intestinal mucositis., Results: The duodenum and jejunum were significantly (p < 0.05) damaged at the 500 mg/kg MTX dose compared to 300 and 400 mg/kg MTX doses. Dietary Zn supplementation did not induce gut MT in MT(+/+) mice nor ameliorate MTX-induced gut damage in either MT(+/+) or MT(-/-) mice. However, MT(-/-) mice had markedly (p < 0.05) higher histological severity scores and MPO activity compared to MT(+/+) mice, irrespective of dietary Zn. methods: MT-knockout (MT(-/-)) and wild-type (MT(+/+)) mice were fed either a 10 mg/kg (control) or 400 mg/kg diet (high Zn) for 7 d and intestinal mucositis was induced by a single injection of MTX (500 mg/kg) subcutaneously. Mice were sacrificed at 24 and 72 h (n = 8/timepoint/genotype) after the MTX injection while continuing their respective diets. Daily weights were recorded and gut tissues were collected for histology, MT levels and myeloperoxidase (MPO) activity., Conclusions: Dietary Zn supplementation did not ameliorate MTX-induced small bowel damage, possibly signifying a deficiency in induction of MT by Zn. However, the presence of MT was able to reduce histological damage and neutrophil infiltration caused by MTX in the gut.

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 microm) and crypt depth (67 +/- 3 microm) were observed in 5-FU + Iberogast-treated rats compared with 5-FU + Water (224 +/- 13 microm and 48 +/- 2 microm 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.

Mucositis is a common and debilitating side effect of chemotherapy that manifests due to the inability of chemotherapy agents to discriminate between normal and neoplastic cells. This results in ulcerating lesions lining the gastrointestinal tract. Moreover, the development of efficacious treatments for small intestinal mucositis has been hindered as the pathobiology of mucositis is still not fully understood. The small intestine is an extensive organ which is largely inaccessible by conventional means. Non-invasive biomarkers such as small intestinal permeability, H(2) breath tests, serum citrulline tests and the (13)C-sucrose breath test (SBT) have emerged as potential markers of small intestinal function. The SBT is emerging as the more appropriate biomarker to assess chemotherapy-induced mucositis in cancer patients and animal models, where it measures the decrease in sucrase activity associated with villus blunting and crypt disruption. The SBT has been successfully applied to detect mucositis induced by different classes of chemotherapy agents and has been used successfully to monitor small intestinal function with a range of candidate anti-mucositis treatments. We propose the SBT a superior biomarker of small intestinal function that could be successfully applied in clinical practice for monitoring the development of mucositis in cancer patients undergoing chemotherapy.

Beneficial bacteria (probiotics) and probiotic-derived factors have the potential to ameliorate disorders of the intestine. The aim of this study was to compare live Streptococcus thermophilus TH-4 (TH-4), dead TH-4 and TH-4 supernatant in rats treated with 5-Fluorouracil. Rats were randomly allocated to five treatment groups (n=8-10): Saline+Water; 5-FU+Skim Milk; 5-FU+Live TH-4; 5-FU+Supernatant TH-4; and 5-FU+Dead TH-4. 5-FU (150mg.kg(-1)) was administered by a single intraperitoneal injection on day 0; animals were killed on day 4. Treatments were administered daily from days -2 to 3 via oro-gastric gavage. Metabolic parameters were measured daily. Blood was obtained by cardiac puncture, and intestinal tissues removed for quantitative and qualitative histological assessment, including: villous height and area; crypt depth and area, mitotic count and crypt fission; biochemical determination of sucrase and myeloperoxidase (MPO) activity; and disease severity scoring. One-way ANOVA statistical analyses were conducted for the majority of outcome measures. Live TH-4 significantly reduced disease severity score by 13% (p< 0.05), and partially normalised mitotic counts compared with 5-FU+Skim milk controls. Live and supernatant TH-4 reduced crypt fission by 69% and 48% (p< 0.05), respectively, compared to 5-FU+Skim Milk controls. No significant differences (p> 0.05) in the occurrence of bacteraemia were evident across all groups. Live TH-4 partially normalised mitotic count and histological severity score in 5-FU treated rats. The inhibitory effect of live TH-4 and TH-4 supernatant on crypt fission suggests therapeutic utility in the prevention of disorders characterised by increased crypt fission, such as colorectal carcinoma.

Mucositis is a common side-effect of high-dose chemotherapy regimens. Grape seed extract (GSE) represents a rich source of proanthocyanidins with the potential to decrease oxidative damage and inflammation within the gastrointestinal tract. We evaluated GSE for its capacity to decrease the severity of chemotherapy-induced mucositis in vitro and in vivo. In vitro: GSE was administered to IEC-6 intestinal epithelial cells prior to damage induced by 5-Fluorouracil (5-FU). Cell viability was determined by neutral red assay. In vivo: Female Dark Agouti rats (130-180 g) were gavaged with 1 ml GSE (400 mg/kg) daily (day 3-11) and received 5-FU (150 mg/kg) by intraperitoneal (i.p.) injection on day nine to induce mucositis. Rats were sacrificed at day 12 and intestinal tissues collected for myeloperoxidase and sucrase activity assays and histological analyses. Statistical analysis was performed by one-way ANOVA. GSE prevented the decrease in IEC-6 cell viability induced by 5-FU (p < 0.01). Compared with 5-FU controls, GSE significantly reduced myeloperoxidase activity by 86% and 27% in the proximal jejunum (p < 0.001) and distal ileum (p < 0.05) respectively; decreased qualitative histological scores of damage (p < 0.05) in the proximal jejunum; increased villus height in the proximal jejunum (17%; p < 0.05) and distal ileum (50%; p < 0.01), and attenuated the 5-FU-induced reduction of mucosal thickness by 16% in the jejunum (p < 0.05) and 45% in the ileum (p < 0.01). GSE partially protected IEC-6 cells from 5-FU-induced cytotoxicity and ameliorated intestinal damage induced by 5-FU in rats. GSE may represent a promising prophylactic adjunct to conventional chemotherapy for preventing intestinal mucositis.

Background: Intestinal mucositis is a common and debilitating side-effect of chemotherapy, associated with severe small intestinal inflammation. Marine oils, such as Lyprinol, a lipid extract derived from New Zealand Green-lipped Mussels, rich in long-chain omega-3 polyunsaturated fatty acids (n-3 PUFA), have demonstrated therapeutic potential for the treatment of inflammatory conditions. We assessed the effects of Lyprinol on the severity of 5-fluorouracil (5-FU)-induced mucositis in female Dark Agouti rats., Results: Small intestinal weight was significantly greater in rats treated with 5-FU+HDL, 5-FU+LDL and 5-FU+FO compared to 5-FU-treated controls (p < 0.05). Myeloperoxidase activity in the proximal and mid small intestine were significantly lower in 5-FU+OO-treated rats compared to 5-FU+vehicle-treated controls (p < 0.05). Histological damage severity was elevated in 5-FU+vehicle, 5-FU+OO and 5-FU+FO-treated rats compared to saline-treated controls, but not in rats treated with 5-FU+HDL or 5-FU+LDL. SBT results and biochemically-assessed sucrase activity were lower in all 5-FU-treated rats compared to saline-treated controls. 5-FU+HDL treated animals had significantly longer crypts and increased proliferation in the mid small intestine compared to 5-FU+vehicle rats (p < 0.05)., Conclusion: Lyprinol treatment in rats with 5-FU-induced mucositis only minimally decreased indicators of intestinal integrity. Further studies of marine oils high in omega-3 PUFA content are warranted for the potential prophylactic treatment of intestinal mucositis., Methods: Rats were allocated to six groups (n = 8/group); Saline+vehicle, 5-FU+vehicle, 5-FU+high-dose Lyprinol (5-FU+HDL), 5-FU+low-dose Lyprinol (5-FU+LDL), 5-FU+olive oil (5-FU+OO), and 5-FU+fish oil (5-FU+FO). Treatments were administered via oro-gastric gavage from days 0-7. Mucositis was induced on day 5 by 5-FU injection (150mg/kg i.p.). (13)C-sucrose breath tests (SBT) were conducted on days 0, 5 and 8 to assess small intestinal function. Rats were sacrificed on day 8 and small intestinal tissues collected for histological and biochemical analysis.

Although probiotics are beginning to enter mainstream medicine for disorders of the colon, their effects on the small bowel remain largely unexplored. We investigated the recently identified probiotic, Lactobacillus fermentum (L. fermentum) BR11 (BR11) and the prebiotic, fructo-oligosaccharide (FOS), both individually and in synbiotic combination, for their potential to alleviate intestinal mucositis. From Days 0-9, rats consumed skim milk (SM; saline + SM), low dose (LD-BR11; 1 x 10(6)cfu/ml), high dose (HD-BR11; 1 x 10(9)cfu/ml), LD-FOS (3%), HD-FOS (6%), or synbiotic (HD-BR11/FOS). On Day 7, rats were injected with 5-fluorouracil (5-FU; 150 mg/kg). All rats were sacrificed on Day 10. Intestinal tissues were collected for quantitative histology, sucrase, and myeloperoxidase (MPO) determinations. 5-FU decreased sucrase activity, villus height, crypt depth, and crypt cell proliferation compared to controls. Compared to 5-FU + SM, histological damage severity scores were increased for all treatments, although all were effective at reducing jejunal inflammation, indicated by reduced MPO activity (P < 0.05). The combination of BR11 and FOS did not provide additional protection. Moreover, HD-FOS and the synbiotic actually increased clinical mucositis severity (P < 0.05). We conclude that L. fermentum BR11 has the potential to reduce inflammation of the upper small intestine. However, its combination with FOS does not appear to confer any further therapeutic benefit for the alleviation of mucositis.

Background: The Sucrose Breath Test (SBT) is a simple noninvasive technique for the detection of small intestinal mucositis., Aim: We utilised rat models of intestinal mucositis induced by different classes of chemotherapeutic agents to broaden application of the SBT., Methods: Mucositis was induced in rats by injection of Doxorubicin (Dox), Etoposide (Etop), Irinotecan (Irin), or Cyclophosphamide (Cy) and Etop in combination (Cy+Etop). The SBT was carried out following sucrose gavage, 72 h after chemotherapy. At kill, intestinal tissues were collected for mucositis assessments., Results: SBT for controls was 16.0 +/- 0.6% (mean +/- SEM) cumulative dose at 90 min. Irin, Doxo, Etop, and Cy+Etop significantly decreased the SBT to 53%, 43%, 32% and 30% of saline control values, respectively (p < 0.01) whilst sucrase activity was correspondingly decreased to 60%, 36%, 14% and 2%. There was good concordance with histological mucositis severity in the jejunum, with median scores of 11, 19, 28 and 27. Correlations between SBT, sucrase activity, and histological severity score yielded r(2) values of 0.82., Conclusions: The SBT detected mucositis induced by the alkylating agent, anthracycline and DNA-topoisomerase inhibitor classes, facilitating the detection of small intestinal dysfunction, providing a further means to screen newly-developed drugs for intestinal side-effects.

Background: Currently, there are no available effective preventative or adjunctive agents to alleviate symptoms of chemotherapy-induced mucositis. This is compounded by the absence of a recognized and validated noninvasive biomarker to assess gut function. This study investigated the effects of orally ingested Streptococcus thermophilus (TH-4) on chemotherapy-induced small intestinal damage in rats using the noninvasive (13)C-sucrose breath test (SBT)., Methods: Gastrointestinal damage was induced in 27 female dark agouti rats (148 +/- 1g) with MTX (1.5 mg/kg; i.m.). Rats received MTX or saline at 0 h; with daily treatment of: TH-4 at doses of 10(9) (high), 10(8) (low) cfu/mL, or skim milk (vehicle), 48 h pre and 96 h post-MTX. The noninvasive (13)C-sucrose breath test (SBT) was conducted at -24, 24 and 96 h post-MTX to monitor gut function. At sacrifice, small intestinal tissues were collected for determinations of sucrase activity, myeloperoxidase (MPO) activity and histological assessment., Results: MTX + vehicle and MTX + low TH-4-treated rats produced significantly lower SBT and sucrase activity results compared to saline controls (p < 0.001). In contrast, MTX + high TH-4 treatment showed no significant differences in the SBT compared to saline controls, and the SBT results were significantly higher compared to MTX + vehicle and MTX + low TH-4 (p < 0.05). MPO levels were significantly elevated (p < 0.05) in MTX + vehicle and MTX + low TH-4, but not following MTX + high TH-4 treatment, compared to saline controls. This was further confirmed by histological analyses., Conclusion: Oral ingestion of TH-4 at 10(9) cfu/mL is capable of partially attenuating small bowel damage in rats. The noninvasive SBT is a useful technique to longitudinally assess the efficacy of treatments or interventions for small bowel disease.

Mucositis is a debilitating side-effect of chemotherapy which affects the mucosa of the gastrointestinal tract, particularly the small intestine. Currently there are no simple, noninvasive methods to detect and monitor small intestinal function and the severity of mucosal damage. Activity of the brush-border enzyme sucrase provides an indicator of small intestinal absorptive function that remains relatively constant throughout life. Measuring 13CO2 levels in expired breath following ingestion of 13C-sucrose is a non-invasive marker of total intestinal sucrase activity. We evaluated the sucrose breath test (SBT) as an indicator of small intestinal injury and dysfunction, utilizing a rat model of chemotherapy-induced mucositis. SBT results reflected the time-course of damage and repair after methotrexate (MTX) treatment, with damage most severe 72 h after chemotherapy, and repair commencing after 96 h. SBT results correlated significantly with jejunal sucrase activity determined biochemically (r2= 0.89; p < 0.005). Moreover, calcium folinate ingested prior to chemotherapy totally prevented damage to the small intestinal mucosa induced by MTX, as assessed by the SBT in concert with structural, and biochemical indices. The SBT provides a simple, non-invasive, integrated measure of small intestinal damage and function. The SBT holds significant potential to monitor small intestinal function in cancer patients undergoing chemotherapy. This technique possesses further applicability to the screening of newly-developed agents for potential gastrointestinal toxicity including the development of new therapies targeted at minimising or preventing the onset of chemotherapy-induced mucositis.

The central nervous system and gastrointestinal tract form the primary targets of chemotherapy-induced toxicities. Symptoms associated with damage to these regions have been clinically termed chemotherapy-induced cognitive impairment and mucositis. Whilst extensive literature outlines the complex etiology of each pathology, to date neither chemotherapy-induced side-effect has considered the potential impact of one on the pathogenesis of the other disorder. This is surprising considering the close bidirectional relationship shared between each organ; the gut-brain axis. There are complex multiple pathways linking the gut to the brain and vice versa in both normal physiological function and disease. For instance, psychological and social factors influence motility and digestive function, symptom perception, and behaviors associated with illness and pathological outcomes. On the other hand, visceral pain affects central nociception pathways, mood and behavior. Recent interest highlights the influence of functional gut disorders, such as inflammatory bowel diseases and irritable bowel syndrome in the development of central comorbidities. Gut-brain axis dysfunction and microbiota dysbiosis have served as key portals in understanding the potential mechanisms associated with these functional gut disorders and their effects on cognition. In this review we will present the role gut-brain axis dysregulation plays in the chemotherapy setting, highlighting peripheral-to-central immune signaling mechanisms and their contribution to neuroimmunological changes associated with chemotherapy exposure. Here, we hypothesize that dysregulation of the gut-brain axis plays a major role in the intestinal, psychological and neurological complications following chemotherapy. We pay particular attention to evidence surrounding microbiota dysbiosis, the role of intestinal permeability, damage to nerves of the enteric and peripheral nervous systems and vagal and humoral mediated changes. [ABSTRACT FROM AUTHOR]

Mucositis, characterized by ulcerative lesions along the alimentary tract, is a common consequence of many chemotherapy regimens. Chemotherapy negatively disrupts the intestinal microbiota, resulting in increased numbers of potentially pathogenic bacteria, such as Clostridia and Enterobacteriaceae, and decreased numbers of “beneficial” bacteria, such as Lactobacilli and Bifidobacteria. Agents capable of restoring homeostasis in the bowel microbiota could, therefore, be applicable to mucositis. Prebiotics are indigestible compounds, commonly oligosaccharides, that seek to reverse chemotherapy-induced intestinal dysbiosis through selective colonization of the intestinal microbiota by probiotic bacteria. In addition, evidence is emerging that certain prebiotics contribute to nutrient digestibility and absorption, modulate intestinal barrier function through effects on mucin expression, and also modify mucosal immune responses, possibly via inflammasome-mediated processes. This review examines the known mechanisms of prebiotic action, and explores their potential for reducing the severity of chemotherapy-induced mucositis in the intestine. [ABSTRACT FROM PUBLISHER]

We evaluated supernatants (SNs) fromEscherichia coliNissle 1917 (EcN) grown in commonly used growth media for their capacity to affect the viability of Caco-2 colon cancer cells in the presence and absence of 5-Fluorouracil (5-FU) chemotherapy. EcN was grown in Luria-Bertani (LB), tryptone soya (TSB), Man Rogosa Sharpe (MRS), and M17 broth supplemented with 10% (v/v) lactose solution (M17). Human Caco-2 colon cancer cells were treated with DMEM (control), growth media alone (LB, TSB, MRS, and M17) or EcN SNs derived from these 4 media, in the presence and absence of 5-FU. Cell viability, reactive oxygen species (ROS), and cell monolayer permeability were determined. EcN SN in LB medium reduced Caco-2 cell viability significantly, to 51% at 48 h. The combination of this EcN SN and 5-FU further reduced cell viability to 37% at 48 h, compared to 5-FU control. MRS broth and EcN SN in MRS, together with 5-FU, generated significantly lower levels of ROS compared to 5-FU control. However, all 5-FU treatments significantly disrupted the Caco-2 cell barrier compared to control; with no significant differences observed among any of the 5-FU treatments. EcN SNs (LB+) was most effective at decreasing the viability of Caco-2 cells. This could indicate a potential role for this EcN SN in chemoprevention for colon cancer. [ABSTRACT FROM PUBLISHER]

Mucositis is a common side-effect of cancer chemotherapy and radiotherapy. Features of mucositis include erythema, ulceration, and inflammation of the gastrointestinal tract accompanied by clinical symptoms of abdominal pain and digestive disturbances. New treatment strategies are required. Experimental evidence is accumulating showing therapeutic promise for new nutraceutical agents including probiotic bacteria, probiotic-derived factors, prebiotics, and plant extracts. However, the targeted development of new combinations of these agents (synbiotics) to combat mucositis remains largely unexplored. The current review addresses the potential for these nutraceutical agents to reduce the severity of chemotherapy-damaged mucositis by strategically aligning their underlying mechanism of action with features of mucositis pathogenesis. The potential for certain plant extracts to act as prebiotics, in combination with probiotics or their derived factors, is further investigated. These unique synbiotic formulations could form the basis of a new naturally sourced adjunctive approach to cancer chemotherapy. [ABSTRACT FROM PUBLISHER]

Simple Summary: Mucositis is a painful and often debilitating condition associated with cancer treatment. Management of associated symptoms is an important clinical consideration. Animal models are used in mucositis research to model the condition in humans in order to develop novel therapeutic agents to relieve symptoms. Previous animal studies have focused on disease severity and outcomes, but often failed to measure pain. The rat grimace scale (RGS) is a validated observational measure used to gauge pain levels experienced by rats. The aim of this study was to assess the rat grimace scale in a rat model of mucositis, and to examine whether changes in clinical signs and anxiety reflected the grimace responses recorded. We also aimed to determine whether the responses were pain-specific by administering potent opioid painkilling agents. In the present study rat grimace scores did not change significantly between treatments. Development of reliable pain assessment methods in animal models is urgently required to improve model relevance to human clinical practice, in addition to safeguarding animal welfare. The rat grimace scale (RGS) is a measure of spontaneous pain that evaluates pain response. The ability to characterize pain through a non-invasive method has considerable utility for numerous animal models of disease, including mucositis, a painful, self-limiting side-effect of chemotherapy treatment. Preclinical studies investigating novel therapeutics for mucositis often focus on pathological outcomes and disease severity. These investigations fail to measure pain, in spite of reduction of pain being a key clinical therapeutic goal. This study assessed the utility of the RGS for pain assessment in a rat model of mucositis, and whether changes in disease activity index (DAI) and open field test (OFT) reflected the grimace responses recorded. Sixty tumor-bearing female Dark Agouti rats were injected with either saline or 5-Fluourouracil alone, or with co-administration of opioid analgesics. Whilst differences in DAI were observed between treatment groups, no difference in RGS scores or OFT were demonstrated. Significant increases in grimace scores were observed across time. However, whilst a statistically significant change may have been noted, the biological relevance is questionable in terms of practical usage, since an observer is only able to score whole numbers. Development of effective pain assessment methods in animal models is required to improve welfare, satisfy regulatory requirements, and increase translational validity of the model to human patients. [ABSTRACT FROM AUTHOR]