Rat Model Of Mucositis Research Articles

Whey preparation as an adjuvant to minimise the Intestinal inflammatory status in mucositis rat model

To study the effect of Whey Preparation on intestinal mucositis, model developed by administration of single dose of etoposide (60mg/Kg body wt., i.p). The experimental procedure included Adult albino rats (10±1 week old) of Wistar strain (n=30, 6/group). Freshly prepared whey preparation-(100 and 200mg/Kg/body wt.) was administered by orogastric gavage- Pre, both pre and post etoposide injection. Effectiveness of whey preparation was determined by estimating the biochemical parameters including intestinal Tumor Necrosis Factor-α, Interleukin-6, sodium potassium ATPase, inflammatory markers- Cyclooxygenase and Myeloperoxidase along with Nitric Oxide and reduced Glutathione with and without intervention after 72 hrs. of etoposide injection. There was a significant increase in the Tumor Necrosis Factor –α, Interleukin-6 levels and extent of apoptosis in etoposide controls. Etoposide administration caused a significant decreased the activity of Na+-K+ ATPase and reduced glutathione levels in intestinal tissue. However, in the post treatment groups, Tumor Necrosis Factor–α, Interleukin-6 as well as extent of apoptosis were reverted to normal after whey preparation administration.Whey Preparation gavage in both the study groups- pre and both pre and post etoposide exposure showed that intervention was able to preserve/ prevent changes in the biochemical activity. The results support the WP potentials to reduce the deleterious effects of etoposide on normal cells, which leads to mucositis.

Hepcidin expression in the trigeminal ganglion and the oral mucosa in an oral ulcerative mucositis rat model.

Severe intraoral pain induces difficulty in eating and speaking, leading to a decline in the quality of life. However, the molecular mechanisms underlying intraoral pain remain unclear. Here, we investigated gene modulation in the trigeminal ganglion and intraoral pain-related behavior in a rat model of acetic acid-induced oral ulcerative mucositis. Oral ulceration was observed on day 2 after acetic acid treatment to the oral mucosa of male Wistar rats, causing spontaneous pain and mechanical allodynia. Deoxyribonucleic acid microarray analysis of trigeminal ganglion tissue indicated that Hamp (a hepcidin gene that regulates cellular iron transport) was the most upregulated gene. In the oral ulcerative mucositis model, the upregulation of Hamp was also induced in the ulcer region but not in the liver, with no increase in hepcidin levels in the plasma and saliva, indicating that hepcidin was produced locally in the ulcer region in the model. Systemic antibiotic pretreatment did not increase the mRNA levels of Hamp in the trigeminal ganglion and ulcer regions. Hepcidin injection into the oral mucosa enhanced neuronal excitability in response to noxious mechanical stimulation of the oral mucosa in trigeminal spinal subnucleus interpolaris/caudalis neurons. These results imply that oral ulcerative mucositis induces oral mucosal pain because of infectious inflammation of the ulcerative area and potentiates Hamp, which represents anti-bacterial and anti-peptidase gene expression in the ulcer region and trigeminal ganglion. The regulation of cellular iron transport by hepcidin is likely involved in oral ulcerative mucositis-induced pain.

Fabrication, in Vitro, and in Vivo Characterization of Mucoadhesive Berberine-Loaded Blended Wafers for Treatment of Chemotherapy-Induced Oral Mucositis.

This study aims to design and characterize berberine-loaded wafers for the treatment of chemotherapy-induced oral mucositis. Wafers were prepared by lyophilization of hydrogels of various ratios of chitosan (CS)/sodium alginate (SA) as well as CS/hydroxypropyl methylcellulose (HPMC). In vitro release, in vitro mucoadhesion, porosity, and swelling studies were conducted to select the optimized formulations. Moreover, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and mechanical properties studies were also performed for further characterization. The efficacy of optimized berberine-loaded wafers in the treatment of oral mucositis was investigated in a 5FU-induced oral mucositis rat model. F2-CS-SA and F6-CS-HPMC wafers exhibited sustained release profile and excellent mucoadhesion strength. Therefore, these wafers were selected as the optimized formulations. SEM confirmed the porous structure of these wafers and is in agreement with the results of porosity and swelling studies. XRD and FTIR studies indicated that berberine was incorporated into the wafer matrix in the amorphous form. In vivo studies demonstrated that topical application of berberine-loaded optimized wafers reduced significantly the severity of 5FU-induced oral mucositis and decreased the expression of inflammatory markers (TNF-α and IL-1β). The results of in vitro and in vivo studies revealed that berberine-loaded F2-CS-SA and F6-CS-HPMC wafers can be effective in the treatment of chemotherapy-related oral mucositis.

Administration of a Probiotic Mixture Ameliorates Cisplatin-Induced Mucositis and Pica by Regulating 5-HT in Rats.

Probiotic-based therapies have been shown to be beneficial for chemotherapy-induced mucositis. Previous research has demonstrated that a probiotic mixture (Bifidobacterium brevis, Lactobacillus acidophilus, Lactobacillus casei, and Streptococcus thermophilus) can ameliorate chemotherapy-induced mucositis and dysbiosis in rats, but the underlying mechanism has not been completely elucidated. We aimed to determine the inhibitory effects of the probiotic mixture on cisplatin-induced mucositis and pica and the underlying mechanism, focusing on the levels of 5-hydroxytryptamine (5-HT, serotonin) regulated by the gut microbiota. A rat model of mucositis and pica was established by daily intraperitoneal injection of cisplatin (6 mg/kg) for 3 days. In the probiotic+cisplatin group, predaily intragastric injection of the probiotic mixture (1 × 109 CFU/kg BW) was administrated for 1 week before cisplatin injection. This was then followed by further daily probiotic injections for 6 days. Histopathology, pro-/anti-inflammatory cytokines, oxidative status, and 5-HT levels were assessed on days 3 and 6. The structure of the gut microbiota was analyzed by 16S rRNA gene sequencing and quantitative PCR. Additionally, 5-HT levels in enterochromaffin (EC) cells (RIN-14B cell line) treated with cisplatin and/or various probiotic bacteria were also determined. The probiotic mixture significantly attenuated kaolin consumption, inflammation, oxidative stress, and the increase in 5-HT concentrations in rats with cisplatin-induced intestinal mucositis and pica. Cisplatin markedly increased the relative abundances of Enterobacteriaceae_other, Blautia, Clostridiaceae_other, and members of Clostridium clusters IV and XIVa. These levels were significantly restored by the probiotic mixture. Importantly, most of the genera increased by cisplatin were significantly positively correlated with colonic 5-HT. Furthermore, in vitro, the probiotic mixture had direct inhibitory effects on the 5-HT secretion by EC cells. The probiotic mixture protects against cisplatin-induced intestine injury, exhibiting both anti-inflammatory and antiemetic properties. These results were closely related to the reestablishment of intestinal microbiota ecology and normalization of the dysbiosis-driven 5-HT overproduction.

Two Mixed-ligand Coordination Polymers: Treatment Activity on Acute Oral Mucositis during Orthodontic Process by Reducing Inflammatory Response.

By modulating the metal centers to adjust the coordination surroundings of the products, two mixed-linker coordination polymers [Cu2(L)(biz)(OH)]·H2O (1) and [Zn(HL)(biz)] (2) (H3L = 5-(4-carboxybenzyloxy)isophthalic acid, biz = benzimidazole), have been produced under mild hydrothermal conditions. To develop new candidates for the acute oral mucositis during orthodontic process, the acute oral mucositis rat model was constructed and the enzyme linked immunosorbent assay (ELISA) was used to find out the release levels of inflammatory cytokines Tumor Necrosis Factor-α (TNF-α) and Interleukin-1β (IL-1β). Next, the activation of the AKT signaling pathway was estimated through judging the relative expression of the inflammatory genes in the oral mucosa cells via reverse transcription-polymerase chain reaction (RT-PCR). After compounds treatment, the expression level of the AKT signaling pathway was evaluated by a western blot. Finally, the quantity of the reactive oxygen species (ROS) in the oral mucosa cells was gauged with ROS detection kit. All the results in this research indicated the much more excellent treatment activity of compound 1 than 2 on the acute oral mucositis.

Use of the Rat Grimace Scale to Evaluate Visceral Pain in a Model of Chemotherapy-Induced Mucositis.

Simple SummaryMucositis 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.

Amitriptyline prevents CPT-11-induced early-onset diarrhea and colonic apoptosis without reducing overall gastrointestinal damage in a rat model of mucositis.

Gastrointestinal mucositis (GIM) is one of the most debilitating side effects of the chemotherapy agent, irinotecan hydrochloride (CPT-11). The toll-like receptor (TLR) pathway is a key mediator implicated in the pathophysiology underlying GIM. The tricyclic antidepressant amitriptyline has been shown to inhibit TLR2 and TLR4 activity in in vitro models. The aim of this study was therefore to investigate the effect of amitriptyline on the development of GIM following CPT-11. Male albino Wistar rats were treated with either CPT-11 (125mg/kg, i.p., n = 18), amitriptyline (20mg/kg, n = 18), both agents (n = 18), or vehicle control (n = 18) and killed at 6, 48, or 96h. Differences between groups in measurements of gastrointestinal toxicity (diarrhea and weight loss), mucosal injury (apoptosis and histopathology score), colonic expression of TLRs, and pro-inflammatory cytokines were determined. CPT-11-induced diarrhea and colonic apoptosis were inhibited by amitriptyline at 6h. However, rats were not protected from weight loss or mucosal injury over the time course of CPT-11-induced GIM. Interleukin-1 beta transcript expression was significantly decreased with amitriptyline treatment at 6h, although protein expression did not differ between groups. There was no change in TLR4 or TLR2 expression in any group. Prophylactic amitriptyline was able to inhibit early intestinal damage in this rat model of CPT-11-induced GIM, but exacerbated late-onset injury. These findings do not support use of amitriptyline as an approach for mitigation of GIM in this setting.

Effect of Oral Insulin on the Severity and Recovery of Methotrexate-Induced Gastrointestinal Mucositis in the Rat.

Gastrointestinal (GI) mucositis is an adverse-effect of chemo- and radiotherapy. Oral insulin has been suggested as possible intestinal growth factor and possible intervention for GI mucositis. We aimed to determine the effect of oral insulin on the severity and recovery of mucositis in a methotrexate (MTX)-induced GI mucositis rat model. Male Wistar rats (n = 24) received a single injection of 60 mg/kg MTX intravenously at day 0. From day -3 oral insulin was added to the drinking water. Group MTX received normal drinking water, group MTX+INS0.5 received 0.5 U/mL insulin, and group MTX+INS1 received 1 U/mL insulin in drinking water. The severity of mucositis was determined by intake, bodyweight, illness, and plasma citrulline. In the recovery phase, the function of the gut was tested with an oral glucose tolerance test, and villus and crypt length of the small intestine were measured. MTX-induced mucositis in all 3 groups and oral insulin did not cause a change in the severity of mucositis, with comparable bodyweight, food intake, and water intake. Oral insulin did not alter the enterocyte mass, determined with plasma citrulline. The glucose level after bolus was higher in the MTX group than the MTX+INS1 group (P < 0.05). Histology was not significant different between all groups. Oral insulin does not alter the severity or the acceleration of recovery of mucositis. Therefore, we conclude that it is not useful to further study oral insulin as possible intervention to prevent or treat chemotherapy-induced GI mucositis.

Effects of Supernatants from Escherichia coli Nissle 1917 and Faecalibacterium prausnitzii on Intestinal Epithelial Cells and a Rat Model of 5-Fluorouracil-Induced Mucositis

ABSTRACTFaecalibacterium 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.

Differential Effectiveness of Clinically-Relevant Analgesics in a Rat Model of Chemotherapy-Induced 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.

Effect of minimal enteral feeding on recovery in a methotrexate-induced gastrointestinal mucositis rat model.

PurposePatients suffering from gastrointestinal mucositis often receive parenteral nutrition as nutritional support. However, the absence of enteral nutrition might not be beneficial for the intestine. We aimed to determine the feasibility of minimal enteral feeding (MEF) administration in a methotrexate (MTX)-induced mucositis rat model and thereby determine the effect of MEF on recovery.MethodsMale Wistar rats were attached to swivel systems from day 1 to 5 after 45 mg/kg MTX IV injection. The MTX group continued ad libitum feeding, and the MTX + MEF group continued ad libitum feeding and received from day 1 to 5 continuously MEF. MEF consisted of 20 % of their normal caloric intake. We measured body weight, intake, and plasma citrulline. At day 10, the rats were terminated and villus and crypt length were measured.ResultsThe administration of MEF caused no increased severity of mucositis phenotype, with comparable caloric intake, body weight, and plasma citrulline during mucositis. The recovery of plasma citrulline levels was not different between both groups. At day 7 and 8, the MTX + MEF group gained significantly more weight (p < 0.05 and p < 0.01, respectively), and at day 8 and 9 the total caloric intake was significantly increased (p < 0.01 and p < 0.05, respectively) compared to the MTX group. At day 10, the rats from the MTX + MEF group showed a significant increase in jejunal villus length compared to the MTX group (p < 0.05).ConclusionsThis is the first study in which the feasibility of MEF administration during chemotherapy-induced mucositis was determined. This study indicates that MEF administration is feasible during mucositis and suggests that MEF accelerates recovery after MTX-induced mucositis.

Assessment of the effect of laser irradiations at different wavelengths (660, 810, 980, and 1064 nm) on autophagy in a rat model of mucositis

It is known that high-dose radiation has an effect on tissue healing, but tissue healing does not occur when low dose radiation is applied. To clarify this issue, we compare the treatment success of low dose radiation with programmed cell death mechanisms on wounded tissue. In this study, we aimed to investigate the interactions of low and high-dose radiation using an autophagic mechanism. We included 35 adult Wistar-Albino rats in this study. All animals were injected with 100 mg/kg of 5-fluorouracil (5-FU) on the first day and 65 mg/kg of 5-FU on the third day. The tips of 18-gauge needles were used to develop a superficial scratching on the left cheek pouch mucosa by dragging in a linear movement on third and fifth days. After mucositis formation was clinically detected, animals were divided into five groups (n = 7). Different wavelengths of laser irradiations (1064 nm, Fidelis Plus, Fotona, Slovenia; 980 nm, FOX laser, A.R.C., Germany; 810 nm, Fotona XD, Fotona, Slovenia; 660 nm, HELBO, Medizintechnik GmbH, Wels, Austria) were performed on four groups once daily for 4 days. The laser irradiation was not performed on the control group. To get the tissue from the left cheek at the end of fourth day from all animals, oval excisional biopsy was performed. Molecular analysis assessments of pathological and normal tissue taken were performed. For this purpose, the expression analysis of autophagy genes was performed. The results were evaluated by normalization and statistics analysis. We found that Ulk1, Beclin1, and Atg5 expression levels were increased in the rats when the Nd:YAG laser was applied. This increase showed that a 1064-nm laser is needed to activate the autophagic mechanism. However, in the diode applications, we found that Beclin1, Atg10, Atg5, and Atg7 expressions numerically decreased. Atg5 is responsible for the elongation of autophagosome. Becn1 is a control gene in the control mechanism of autophagy. The reduction of the expression of these genes leads us to think that it may depend on the effect of drug (5-FU) used to form model. Expressions of therapeutic genes increase to ensure hemostasis, but in our study, expressions were found to decrease. More detailed studies are needed.

Substantial decreases in the number and diversity of microbiota during chemotherapy-induced gastrointestinal mucositis in a rat model.

Earlier, we showed in acute myeloid leukemia (AML) patients that the microbiota changes dramatically during anticancer treatment, coinciding with gastrointestinal mucositis: The commensal anaerobic populations reduce in favor of potential pathogens. Therefore, interventions targeting the microbiota during mucositis might be interesting but can better be tested in animals than in vulnerable mucositis patients. Here, we aimed to study the potential microbial changes during methotrexate (MTX)-induced gastrointestinal mucositis in a well-established rat model and to study whether this model can be used for future microbial intervention studies. After injection with MTX or saline (day 0), rats were sacrificed between days 2 and 11. Plasma citrulline level, jejunal histology, and the number and diversity of intestinal bacteria in feces (using fluorescence in situ hybridization (FISH)) were determined. Mucositis was most severe on day 4 when food intake, plasma citrulline, and villus length were the lowest, compared with controls (P < 0.0125). At the same time, MTX-treated rats showed an overall decrease (705-fold) in most bacteria (using a universal probe), compared with controls (P < 0.125). Reduced bacterial presence was related with the presence of diarrhea and a reduced villus length (rho = 0.38, P < 0.05). At day 4, there was an absolute and relative decrease of anaerobes (13-fold and -58 %, respectively) and streptococci (296-fold and -1 %, respectively) but a relative increase of Bacteroides (+49 %), compared with controls (P < 0.125). In the mucositis rat model, we found substantial decreases in the number and diversity of microbiota, resembling earlier findings in humans. The model therefore seems well suited to study the effects of different microbial interventions on mucositis, prior to performing human studies.

Low molecular weight procyanidins from grape seeds enhance the impact of 5-Fluorouracil chemotherapy on Caco-2 human colon cancer cells.

ObjectiveGrape seed procyanidins (PC) are flavan-3-ol oligomers and polymers known for their biological activity in the gut. Grape seed extract (GSE) have been reported to reduce intestinal injury in a rat model of mucositis. We sought to investigate effects of purified PC fractions differing in mean degree of polymerization (mDP) combined with 5-Fluorouracil (5-FU) chemotherapy on the viability of colon cancer cells (Caco-2).DesignSixPC fractions (F1-F6) were isolated from Cabernet Sauvignon seeds at two ripeness stages: pre-veraison unripe (immature) and ripe (mature), utilizing step gradient, low-pressure chromatography on a Sephadex LH-20 resin. Fractions were tested on Caco-2 cells, alone and in combination with 5-FU. Eluted fractions were characterized by phloroglucinolysis and gel permeation chromatography. Cell viability was determined by the 3-(4,5-Dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide) (MTT) assay.ResultsAll isolated fractions significantly reduced Caco-2 cell viability compared to the control (P<0.05), but F2 and F3 (mDP 2–6) were the most active fractions (immature F2 = 32% mDP 2.4, F3 = 35% mDP 5.8 and mature F2 = 13% mDP 3.6 and F3 = 17% mDP 5.9; percentage of viable cells remaining) on Caco-2 cells. When combined with 5-FU, immature fractions F1-F3 enhanced the cell toxicity effects of 5-FU by 27–73% (P<0.05). Mature seed PC fractions (F1–F4) significantly enhanced the toxicity of 5-FU by 60–83% against Caco-2 cells (P<0.05). Moreover, some fractions alone were more potent at decreasing viability in Caco-2 cells (P<0.05; immature fractions = 65–68% and mature fractions = 83–87%) compared to 5-FU alone (37%).ConclusionsPCs of mDP 2–6 (immature F1-F3 and mature F1 and F4)not only enhanced the impact of 5-FU in killing Caco-2 cells, but also surpassed standard 5-FU chemotherapy as an anti-cancer agent.The bioactivity of PC is therefore attributed primarily to lower molecular weight PCs.

Ostrich oil failed to improve intestinal barrier function following 5‐fluorouracil‐induced mucositis in rats (1111.5)

INTRODUCTION. Mucositis is characterized by intestinal barrier disruption following chemotherapy. Emu Oil promoted small intestinal repair in a rat model of mucositis (Mashtoub, 2013). However, the effects of Ostrich Oil (OO) remain unexplored. We investigated the effects of OO on mucin‐secreting goblet cells (GC) during the recovery phase of mucositis. METHODS. Female Dark Agouti rats were allocated to groups (n=8/group): Saline+Water; Saline+OO; 5‐Fluorouracil (5‐FU)+Water; 5‐FU+OO. Mucositis was induced on day 5 by 5‐FU injection and rats were euthanized on day 10. Intestinal villus height (VH), crypt depth (CD) and GC were quantified. p&lt;0.05 was considered significant. RESULTS. Compared to water controls, VH was increased 15% by OO (p&lt;0.05), however, VH was unaffected by 5‐FU. 5‐FU tended to decrease GC count in the villi, relative to water controls (p=0.069). GC count was unaffected by OO in 5‐FU‐treated rats compared to 5‐FU controls. CD was increased 24% by 5‐FU (p&lt;0.01); an effect that was not altered by OO. 5‐FU reduced GC count in crypts (33%; p&lt;0.01) compared to water controls. However, OO did not attenuate the decrease in GC count in 5‐FU‐treated rats. CONCLUSIONS. Ostrich Oil treatment failed to improve intestinal barrier function indicated by mucin‐secreting goblet cells. As this is the first report of Ostrich Oil in bowel disease, further studies are required to explore dosage and timing regimens.Grant Funding Source: Supported by The Rural Industries Research and Development Corporation Australia

Grape Seed Extract Dose-Responsively Decreases Disease Severity in a Rat Model of Mucositis; Concomitantly Enhancing Chemotherapeutic Effectiveness in Colon Cancer Cells

ObjectiveMucositis is a serious disorder of the gastrointestinal tract that results from cancer chemotherapy. We investigated the effects of increasing grape seed extract doses on the severity of chemotherapy in a rat model and its coincident impact on chemotherapeutic effectiveness in colon cancer cells.DesignFemale Dark Agouti rats were gavaged with grape seed extract (400–1000 mg/kg) or water (day 3–11) and were injected intraperitoneally with 5-Fluorouracil (150 mg/kg) or saline (control) on day 9 to induce mucositis. Daily metabolic data were collected and rats were sacrificed on day 12. Intestinal tissues were collected for histological and myeloperoxidase analyses. Caco-2 cell viability was examined in response to grape seed extract in combination with 5-Fluorouracil by 3-(4,5-Dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide) assay.ResultsCompared with 5-Fluorouracil controls, grape seed extract (400–1000 mg/kg) significantly decreased the histological damage score (P<0.05) in the jejunum. Grape seed extract (1000 mg/kg) increased jejunal crypt depth by 25% (P<0.05) in 5-Fluorouracil treated rats compared to 5-Fluorouracil controls, and attenuated the 5-Fluorouracil -induced reduction of mucosal thickness (25%, P<0.05). Grape seed extract (600 mg/kg) decreased myeloperoxidase activity by 55% (P<0.01) compared to 5-Fluorouracil controls. Grape seed extract was more effective at ameliorating 5-Fluorouracil induced intestinal injury, with effects most pronounced in the proximal jejunum. Grape seed extract (10–25 ug/mL) significantly enhanced the growth-inhibitory effects of 5-Fluorouracil by 26% (P<0.05) in Caco-2 cells and was more potent than 5-Fluorouracil at 50–100 µg/mL.ConclusionGrape seed extract may represent a new therapeutic option to decrease the symptoms of intestinal mucositis while concurrently impacting on the viability of colon cancer cells.

Effects of Streptococcus thermophilus TH-4 in a rat model of doxorubicin-induced mucositis

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 109 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.

Mo2128 Parenteral Feeding During Methotrexate-Induced Gastrointestinal Mucositis Prevents Weight Loss in the Rat

summary Background & aims: It is unknown what feeding strategy to use to prevent weight loss in patients with chemotherapy-induced gastrointestinal mucositis. When possible, enteral nutrition is preferred to parenteral nutrition because of negative side effects. In a mucositis rat model, we demonstrated disaccharide maldigestion and fat malabsorption but up to normal absorption of glucose and amino acids upon their continuous enteral administration. We now determined the effects of four different (par) enteral feeding strategies during mucositis on body weight and intestinal recovery. Methods: From days 2 to 5 after injection with methotrexate (60 mg/kg), rats continued ad libitum enteral feeding with purified diet (AIN-93G, strategy 1), received continuous enteral feeding [forcefeeding, normal daily amounts] with glucose and amino acids (Nutriflex , strategy 2) or with standard formula (Nutrini, strategy 3), or received continuous parenteral feeding with standard formula (NuTRIflex Lipid, strategy 4). Saline-treated controls continued ad libitum purified diet. Results: From day 2 on, methotrexate-treated ad libitum-fed rats showed a reduced food intake and body weight (P < 0.05), as seen before. Most continuously enterally-fed rats (88%) were terminated early because of severe abdominal distention. Parenterally-fed rats grew similarly like controls. On day 5, the jejunum of methotrexate-treated ad libitum-fed rats showed hypertrophic crypts and a normal villus length. In contrast, parenterally-fed rats showed no increase in crypt length and a reduced villus length, compared with controls (P < 0.05). Conclusion: Continuous enteral feeding in normal daily amounts during mucositis is poorly tolerated in rats. Parenteral feeding prevents weight loss during mucositis while enteral feeding in limited amounts accelerates intestinal recovery.

Parenteral feeding during methotrexate-induced gastrointestinal mucositis prevents weight loss in the rat

Summary Background & aims It is unknown what feeding strategy to use to prevent weight loss in patients with chemotherapy-induced gastrointestinal mucositis. When possible, enteral nutrition is preferred to parenteral nutrition because of negative side effects. In a mucositis rat model, we demonstrated disaccharide maldigestion and fat malabsorption but up to normal absorption of glucose and amino acids upon their continuous enteral administration. We now determined the effects of four different (par)enteral feeding strategies during mucositis on body weight and intestinal recovery. Methods From days 2 to 5 after injection with methotrexate (60 mg/kg), rats continued ad libitum enteral feeding with purified diet (AIN-93G, strategy 1), received continuous enteral feeding [force-feeding, normal daily amounts] with glucose and amino acids (Nutriflex ® , strategy 2) or with standard formula (Nutrini ® , strategy 3), or received continuous parenteral feeding with standard formula (NuTRIflex ® Lipid, strategy 4). Saline-treated controls continued ad libitum purified diet. Results From day 2 on, methotrexate-treated ad libitum-fed rats showed a reduced food intake and body weight ( P P Conclusion Continuous enteral feeding in normal daily amounts during mucositis is poorly tolerated in rats. Parenteral feeding prevents weight loss during mucositis while enteral feeding in limited amounts accelerates intestinal recovery.

Lactose maldigestion during methotrexate-induced gastrointestinal mucositis in a rat model

Patients with chemotherapy-induced gastrointestinal mucositis suffer from anorexia, diarrhea, and stomach pain, often causing weight loss and malnutrition. When the intestinal function during mucositis would be known, a rational feeding strategy might improve the nutritional state, accelerate recuperation, and increase survival of mucositis patients. We developed a methotrexate (MTX)-induced mucositis rat model to study nutrient digestion and absorption. To determine lactose digestion and absorption of its derivative glucose during mucositis, we injected Wistar rats intravenously with MTX (60 mg/kg) or 0.9% NaCl (controls). Four days later, we orally administered trace amounts of [1-(13)C]lactose and [U-(13)C]glucose and quantified the appearance of labeled glucose in the blood for 3 h. Finally, we determined plasma citrulline level and harvested the small intestine to assess histology, myeloperoxidase level, glycohydrolase activity, immunohistochemical protein, and mRNA expression. MTX-treated rats showed profound villus atrophy and epithelial damage. During the experimental period, the absorption of lactose-derived [1-(13)C]glucose was 4.2-fold decreased in MTX-treated rats compared with controls (P < 0.01). Lactose-derived [1-(13)C]glucose absorption correlated strongly with villus length (rho = 0.86, P < 0.001) and with plasma citrulline level (rho = 0.81, P < 0.001). MTX treatment decreased jejunal lactase activity (19.5-fold, P < 0.01) and immunohistochemical protein and mRNA expression (39.7-fold, P < 0.01) compared with controls. Interestingly, MTX treatment did not affect the absorption of [U-(13)C]glucose during the experimental period. We conclude that lactose digestion is severely decreased during mucositis while glucose absorption is still intact, when supplied in trace amounts. Plasma citrulline level might be a useful objective, noninvasive marker for lactose maldigestion during mucositis in clinic.