Yoghurts containing probiotics reduce disruption of the small intestinal barrier in methotrexate-treated rats

Probiotics and Probiotic-like Agents against Chemotherapy-Induced Intestinal Mucositis: A Narrative Review

Cancer chemotherapy has allowed many patients to survive, but not without risks derived from its adverse effects. Drugs, such as 5-fluorouracil, irinotecan, oxaliplatin, methotrexate, and others, as well as different drug combinations trigger intestinal mucositis that may cause or contribute to anorexia, pain, diarrhea, weight loss, systemic infections, and even death. Dysbiosis is a hallmark of chemotherapy-induced intestinal mucositis and diarrhea, and, therefore, strategies aimed at modulating intestinal microbiota may be useful to counteract and prevent those dreadful effects. This narrative review offers an overview of the studies performed to test the efficacy of probiotics and probiotic-like agents against chemotherapy-induced intestinal mucositis and its consequences. Microbiota modulation through the oral administration of different probiotics (mainly strains of Lactobacillus and Bifidobacterium), probiotic mixtures, synbiotics, postbiotics, and paraprobiotics has been tested in different animal models and in some clinical trials. Regulation of dysbiosis, modulation of epithelial barrier permeability, anti-inflammatory effects, modulation of host immune response, reduction of oxidative stress, or prevention of apoptosis are the main mechanisms involved in their beneficial effects. However, the findings are limited by the great heterogeneity of the preclinical studies and the relative lack of studies in immunocompromised animals, as well as the scarce availability of results from clinical trials. Despite this, the results accumulated so far are promising. Hopefully, with the aid of these agents, intestinal mucositis will be less impactful to the cancer patient in the near future.

Review on the effect of chemotherapy on the intestinal barrier: Epithelial permeability, mucus and bacterial translocation

Chemotherapy kills fast-growing cells including gut stem cells. This affects all components of the physical and functional intestinal barrier, i.e., the mucus layer, epithelium, and immune system. This results in an altered intestinal permeability of toxic compounds (e.g., endotoxins) as well as luminal bacterial translocation into the mucosa and central circulation. However, there is uncertainty regarding the relative contributions of the different barrier components for the development of chemotherapy-induced gut toxicity. This review present an overview of the intestinal mucosal barrier determined with various types of molecular probes and methods, and how they are affected by chemotherapy based on reported rodent and human data. We conclude that there is overwhelming evidence that chemotherapy increases bacterial translocation, and that it affects the mucosal barrier by rendering the mucosa more permeable to large permeability probes. Chemotherapy also seems to impede the intestinal mucus barrier, even though this has been less clearly evaluated from a functional standpoint but certainly plays a role in bacteria translocation. Combined, it is however difficult to outline a clear temporal or succession between the different gastrointestinal events and barrier functions, especially as chemotherapy-induced neutropenia is also involved in intestinal immunological homeostasis and bacterial translocation. A thorough characterization of this would need to include a time dependent development of neutropenia, intestinal permeability, and bacterial translocation, ideally after a range of chemotherapeutics and dosing regimens.

The Protective Effects of Nutraceutical Components in Methotrexate-Induced Toxicity Models—An Overview

There are multiple concerns associated with methotrexate (MTX), widely recognized for anti-neoplastic and anti-inflammatory effects in life-threatening disease conditions, i.e., acute lymphoblastic leukemia, non-Hodgkin’s lymphoma, psoriasis, and rheumatoid arthritis, due to long-term side effects and associated toxicity, which limits its valuable potential. MTX acts as an inhibitor of dihydrofolate reductase, leading to suppression of purine and pyrimidine synthesis in high metabolic and turnover cells, targeting cancer and dysregulated immune cells. Due to low discrimination between neoplastic cells and naturally high turnover cells, MTX is prone to inhibiting the division of all fast-dividing cells, causing toxicity in multiple organs. Nutraceutical compounds are plant-based or food-derived compounds, used for their preventive and therapeutic role, ascertained in multiple organ dysfunctions, including cardiovascular disease, ischemic stroke, cancer, and neurodegenerative diseases. Gut microbiota and microbiota-derived metabolites take part in multiple physiological processes, their dysregulation being involved in disease pathogenesis. Modulation of gut microbiota by using nutraceutical compounds represents a promising therapeutic direction to restore intestinal dysfunction associated with MTX treatment. In this review, we address the main organ dysfunctions induced by MTX treatment, and modulations of them by using nutraceutical compounds. Moreover, we revealed the protective mechanisms of nutraceuticals in MTX-induced intestinal dysfunctions by modulation of gut microbiota.

Factors associated with the prescription of probiotics in patients with inflammatory bowel disease: a cross-sectional study

BACKGRUOUND

Commensal bacteria play an important role in the pathogenesis of inflammatory bowel disease (IBD) and probiotics have been used as treatment options. We aimed to explore the current use of probiotics and factors associated with their prescription in patients with IBD.

METHODS

This cross-sectional study was conducted on a single hospital-based cohort. Patients were eligible if they were ≥18 years old, visited the IBD clinic as an outpatient more than twice during the study period, and had a confirmed diagnosis of IBD. Patients were divided into two groups based on the prescription of probiotics. Clinical assessments were compared between the two groups.

RESULTS

In total, 217 patients were enrolled in this study. In patients with Crohn disease (CD), moderate or severe abdominal pain; prior use of methotrexate (MTX), iron, thiopurines, or biologics; history of IBD-related surgery; and stool frequency were independently associated with the prescription of probiotics. In patients with ulcerative colitis (UC), moderate or severe abdominal pain, hematochezia, stool frequency, and moderate or severe physician global assessment score were independently associated with the prescription of probiotics.

CONCLUSION

Increased disease activity may be associated with fewer prescriptions of probiotics in patients with IBD. However, physicians prescribed probiotics to control symptoms, such as abdominal pain and increased stool frequency in patients with UC and CD, and hematochezia in patients with UC. Additionally, the use of MTX and iron, and a history of IBD-related surgeries were associated with more frequent probiotic prescriptions in patients with CD.

Gut barrier disruption and chronic disease

The intestinal barrier protects the host against gut microbes, food antigens, and toxins present in the gastrointestinal tract. However, gut barrier integrity can be affected by intrinsic and extrinsic factors, including genetic predisposition, the Western diet, antibiotics, alcohol, circadian rhythm disruption, psychological stress, and aging. Chronic disruption of the gut barrier can lead to translocation of microbial components into the body, producing systemic, low-grade inflammation. While the association between gut barrier integrity and inflammation in intestinal diseases is well established, we review here recent studies indicating that the gut barrier and microbiota dysbiosis may contribute to the development of metabolic, autoimmune, and aging-related disorders. Emerging interventions to improve gut barrier integrity and microbiota composition are also described.

Lactobacillus casei Alleviated the Abnormal Increase of Cholestasis-Related Liver Indices During Tuberculosis Treatment: A Post Hoc Analysis of Randomized Controlled Trial

SCOPE

Probiotics are promising in mitigating drug-induced liver injury in animal experiments. However, the clinical evidence is absent. The objective is to investigate the effect of adjunctive Lactobacillus casei on tuberculosis-drug-induced liver injury.

METHODS AND RESULTS

A post hoc analysis is conducted for a previous randomized controlled trial. The trial is registered at the Chinese Clinical Trial Registry (No. ChiCTR-IOR-17013210). Four hundred twenty nine patients are allocated to receive standard tuberculosis therapy alone (control group), or together with 1 × 10¹⁰ colony-forming units (CFU) per day (low-dose group), or 2 × 10¹⁰ CFU per day of L. casei (high-dose group) during tuberculosis treatment. The L. casei supplementation significantly reduced the incidence of the abnormal increase of cholestasis-related liver indices including alkaline phosphatase (p = 0.024) and bilirubin (p = 0.013). Plasma lipopolysaccharide (p = 0.02), intestinal permeability biomarkers including zonula occludens-1 (p = 0.001) and intestinal fatty acid binding protein (p = 0.002) are significantly reduced. The gut microbiota composition is dramatically altered with a reduction of Bacteroidetes (p < 0.001) and a corresponding increase of Actinobacteria (p < 0.001) and Firmicutes (p = 0.003).

CONCLUSIONS

L. casei supplementation is beneficial for suppressing abnormally elevated cholestasis-related liver indices during tuberculosis treatment, which may be related to its modification on blood lipopolysaccharide, intestinal barrier function, and gut microbiota.

Pre-therapy fasting slows epithelial turnover and modulates the microbiota but fails to mitigate methotrexate-induced gastrointestinal mucositis

BACKGROUND

Recent findings by Tang et al. (2020) show dietary restriction (30%, 2 weeks) prevents methotrexate-induced mortality by modulation of the microbiota, specifically the expansion of Lactobacillus. While fundamentally insightful, upscaling this schedule is a major obstacle to clinical uptake. Here, we evaluate a safe and clinically achievable schedule of pre-therapy fasting for 48 h on microbiota composition, body composition and intestinal proliferation, and assess its impact on the severity of methotrexate-induced gastrointestinal mucositis using a validated preclinical rat model.

METHODS

Age- and weight-matched male Wistar rats were treated with a sublethal dose of 45 mg/kg methotrexate with or without pre-therapy fasting. The impact of acute fasting on epithelial proliferation, body composition and the microbiota was assessed using plasma citrulline, Ki67 immunohistochemistry, miniSpec and 16S rRNA sequencing. The severity of gastrointestinal mucositis was evaluated using plasma citrulline and body weight.

RESULTS

Whilst pre-therapy fasting slowed epithelial proliferation and increased microbial diversity and richness, it also induced significant weight loss and was unable to attenuate the severity of mucositis in both age- and weight-matched groups. In contrast to Tang et al., we saw no expansion of Lactobacillus following acute fasting.

CONCLUSIONS

Our findings suggest that the beneficial effects of acute fasting are masked by the detrimental effects on body weight and composition and lacking influence on Lactobacillus. Future studies should consider alternative fasting schedules or aim to induce comparable microbial and mucosal manipulation without compromising body composition using clinically feasible methods of dietary or microbial intervention.

Gut microbiota modulation: a novel strategy for prevention and treatment of colorectal cancer. Oncogene. 2020;39:4925-4943. [PMID: 32514151 PMCID: PMC7314664 DOI: 10.1038/s41388-020-1341-1]

Research about the role of gut microbiome in colorectal cancer (CRC) is a newly emerging field of study. Gut microbiota modulation, with the aim to reverse established microbial dysbiosis, is a novel strategy for prevention and treatment of CRC. Different strategies including probiotics, prebiotics, postbiotics, antibiotics, and fecal microbiota transplantation (FMT) have been employed. Although these strategies show promising results, mechanistically by correcting microbiota composition, modulating innate immune system, enhancing gut barrier function, preventing pathogen colonization and exerting selective cytotoxicity against tumor cells, it should be noted that they are accompanied by risks and controversies that can potentially introduce clinical complications. During bench-to-bedside translation, evaluation of risk-and-benefit ratio, as well as patient selection, should be carefully performed. In view of the individualized host response to gut microbiome intervention, developing personalized microbiome therapy may be the key to successful clinical treatment.

Low-fat yogurt alleviates the pro-inflammatory cytokine IL-1β-induced intestinal epithelial barrier dysfunction

Yogurt is a source of bioactive compounds and probiotic microorganisms that modify immunity and metabolism to benefit human health beyond nutrition. In this study, we examined the capacity of yogurt to prevent epithelial barrier disruption in vitro. Different preparations of yogurt were added apically to Caco-2 monolayers before IL-1β exposure. Dulbecco's modified Eagle medium containing 25% (vol/vol) low-fat yogurt prevented cytokine-induced transepithelial resistance reduction and increases to paracellular permeability measured with fluorescein isothiocyanate-dextran (4 kDa), whereas nonfat yogurt was unable to decrease paracellular permeability to fluorescein isothiocyanate-dextran. Moreover, the concentration of IL-8 in low-fat-yogurt-treated inflamed cells was decreased to 252.40 ± 27.24 pg/mL, which was lower than that of untreated, inflamed cells (407.20 ± 50.05 pg/mL), further indicating the anti-inflammatory roles of low-fat yogurt. The low-fat yogurt was able to downregulate the transcription of myosin light-chain kinase (MLCK) gene, but upregulate the expression of tight junction protein ZO-1 (TJP1). These findings indicate that low-fat yogurt can maintain intestinal barrier integrity better than nonfat yogurt after pro-inflammatory cytokine exposure.

Effects of Probiotic Bacillus as an Alternative of Antibiotics on Digestive Enzymes Activity and Intestinal Integrity of Piglets

The previous study in our team found that supplementation of probiotic Bacillus amyloliquefaciens (Ba) instead of antibiotics promote growth performance of piglets. Hence, the present study was carried out to further demonstrate the effect of Ba replacement of antibiotics on digestive and absorption enzyme activity and intestinal microbiota population of piglets. A total of 90 piglets were selected and divided into three groups: G1 group was fed with basal diet supplemented with 150 mg/Kg aureomycin, G2 group was fed with 1 × 10⁸ cfu/Kg Ba and half dose of aureomycin, G3 group was used the diet with 2 × 10⁸cfu/Kg Ba replaced aureomycin. Each treatment had three replications of 10 pigs per pen. Results indicated that Ba replacement significantly increased the activities of amylase, disaccharides and Na⁺/K⁺-ATPase. And chymotrypsin activity in different section of intestine was dramatically enhanced in half replacement of aureomycin with Ba. Moreover, Ba replacement maintained the intestinal integrity with the significantly decreased activity of DAO compared with aureomycin group. Besides, supplementation with Ba increased the β-diversity of intestinal microbiota. Taken together, the current study indicated that diet supplementation with Ba instead of aureomycin increased the growth performance of piglets by improving the digestive and absorb enzyme activities, enhancing the intestinal integrity and regulating the population of intestinal micrbiota.

Gut microbiome modulation during treatment of mucositis with the dairy bacterium Lactococcus lactis and recombinant strain secreting human antimicrobial PAP

Mucositis is an inflammatory condition of the gut, caused by an adverse effect of chemotherapy drugs, such as 5-fluorouracil (5-FU). In an attempt to develop alternative treatments for the disease, several research groups have proposed the use of probiotics, in particular, Lactic Acid Bacteria (LAB). In this context, the use of recombinant LAB, for delivering anti-inflammatory compounds has also been explored. In previous work, we demonstrated that either Lactococcus lactis NZ9000 or a recombinant strain expressing an antimicrobial peptide involved in human gut homeostasis, the Pancreatitis-associated Protein (PAP), could ameliorate 5-FU-induced mucositis in mice. However, the impact of these strains on the gut microbiota still needs to be elucidated. Therefore, in the present study, we aimed to characterize the effects of both Lactococci strains in the gut microbiome of mice through a 16 S rRNA gene sequencing metagenomic approach. Our data show 5-FU caused a significant decrease in protective bacteria and increase of several bacteria associated with pro-inflammatory traits. The Lactococci strains were shown to reduce several potential opportunistic microbes, while PAP delivery was able to suppress the growth of Enterobacteriaceae during inflammation. We conclude the strain secreting antimicrobial PAP was more effective in the control of 5-FU-dysbiosis.

Enzyme activity and phosphate uptake in the small intestine of Sprague Dawley rats improved by supplementation of infant formula with prebiotics

This study was to identify the effects of prebiotics supplemented in infant formula on enzyme activity and phosphate uptake in the small intestine of Sprague Dawley (SD) rats. Forty-eight healthy SD rats at 15 days old (a week before weaning) with similar weight were randomly divided into 3 groups: A (control group), B, C, with 16 rats per group. Rats in groups A, B, C were fed a standard infant formula, the standard infant formula supplemented with oligosaccharides, and the standard infant formula supplemented with polysaccharides, respectively. The feeding test was conducted for 28 d. Compared with group A, the results showed the following: 1) the activities of sucrose and lactase in the small intestine were significantly increased in SD rats of group C (P < 0.05); 2) the relative expressions of lactase gene in the anterior and posterior segments of the small intestine were significantly increased by 1.68 and 2.26 in SD rats of group C (P < 0.05), and the relative expression of Mgam gene in the posterior segment of the small intestine was significantly increased by 0.99 in SD rats of group C (P < 0.05); 3) the relative expressions of Na/Pi-IIb gene in the anterior and posterior segments of the small intestine were significantly increased by 1.85 and 2.28 in SD rats of group C (P < 0.05). These results indicate that the supplementation of infant formula with prebiotics can promote enzyme activity in the small intestine by increasing the relative expression of enzyme gene or by decreasing intestinal injury, and can increase the relative expression of Na/Pi-IIb gene. The effect of polysaccharides is better than that of oligosaccharides.

TGF-β activity in cow milk and fermented milk products: An in vitro bioassay with oral fibroblasts

OBJECTIVE

Milk is a rich source of transforming growth factor (TGF)-β which supports intestinal mucosal homeostasis of infants. Milk may also have beneficial effects on the integrity of the oral cavity, its being part of the gastrointestinal tract. However, it is unclear if milk and fermented milk products provoke a TGF-β response in oral cells.

MATERIAL AND METHODS

Human gingival fibroblasts were exposed to pasteurized cow milk, yoghurt, sour milk, buttermilk and whey, followed by a reverse transcriptase polymerase chain reaction of the TGF-β target genes interleukin11 (IL11), proteoglycan4 (PRG4), and NADPH oxidase 4 (NOX4). Immunoassays were performed for IL11 and TGF-β in cell culture supernatant and milk products, respectively. Signaling was investigated with the TGF-β receptor type I kinase inhibitor SB431542.

RESULTS

We report here that pasteurized cow milk and the aqueous fractions of yoghurt, sour milk, buttermilk and whey enhanced the expression of IL11, NOX4 and PRG4 in gingival fibroblasts. Moreover, IL11 protein levels in the respective supernatant were significantly increased. Cow milk, yoghurt, sour milk and buttermilk contain approximately 1-2 ng TGF-β1, whereas active TGF-β1 is hardly detectable in whey. SB431542 reduced the response of gingival fibroblasts to pasteurized cow milk and fermented milk products based on IL11 release into the supernatant.

CONCLUSIONS

These results demonstrate that gingival fibroblasts respond to pasteurized cow milk and to fermented milk products with an increased expression of TGF-β target genes.

Animal models of chemotherapy-induced mucositis: translational relevance and challenges

Chemotherapy for cancer patients induces damaging tissue reactions along the epithelium of the gastrointestinal tract (GIT). This chemotherapy-induced mucositis (CIM) is a serious side effect of cytotoxic drugs, and several animal models of CIM have been developed, mainly in rodents and piglets, to help understand the progression of CIM and how to prevent it. Animal models allow highly controlled experimental conditions, detailed organ (e.g., GIT) insights, standardized, clinically relevant treatment regimens, and discovery of new biomarkers. Still, surprisingly few results from animal models have been translated into clinical CIM management and treatments. The results obtained from specific animal models can be difficult to translate to the diverse range of CIM manifestations in patients, which vary according to the antineoplastic drugs, dose, underlying (cancer) disease, and patient characteristics (e.g., age, genetics, and body constitution). Another factor that hinders the direct use of results from animals is inadequate collaboration between basic science and clinical science in relation to CIM. Here, we briefly describe CIM pathophysiology, particularly the basic knowledge that has been obtained from CIM animal models. These model studies have indicated potential new preventive and ameliorating interventions, including supplementation with natural bioactive diets (e.g., milk fractions, colostrum, and plant extracts), nutrients (e.g., polyunsaturated fatty acids, short-chain fatty acids, and glutamine), and growth factor peptides (e.g., transforming growth factor and glucagon-like peptide-2), as well as manipulations of the gut microbiota (e.g., prebiotics, probiotics, and antibiotics). Rodent CIM models allow well-controlled, in-depth studies of animals with or without tumors while pig models more easily make clinically relevant treatment regimens possible. In synergy, animal models of CIM provide the basic physiological understanding and the new ideas for treatment that are required to make competent decisions in clinical practice.

Use of Wild Type or Recombinant Lactic Acid Bacteria as an Alternative Treatment for Gastrointestinal Inflammatory Diseases: A Focus on Inflammatory Bowel Diseases and Mucositis

The human gastrointestinal tract (GIT) is highly colonized by bacterial communities, which live in a symbiotic relationship with the host in normal conditions. It has been shown that a dysfunctional interaction between the intestinal microbiota and the host immune system, known as dysbiosis, is a very important factor responsible for the development of different inflammatory conditions of the GIT, such as the idiopathic inflammatory bowel diseases (IBD), a complex and multifactorial disorder of the GIT. Dysbiosis has also been implicated in the pathogenesis of other GIT inflammatory diseases such as mucositis usually caused as an adverse effect of chemotherapy. As both diseases have become a great clinical problem, many research groups have been focusing on developing new strategies for the treatment of IBD and mucositis. In this review, we show that lactic acid bacteria (LAB) have been capable in preventing and treating both disorders in animal models, suggesting they may be ready for clinical trials. In addition, we present the most current studies on the use of wild type or genetically engineered LAB strains designed to express anti-inflammatory proteins as a promising strategy in the treatment of IBD and mucositis.

Secretion of biologically active pancreatitis-associated protein I (PAP) by genetically modified dairy Lactococcus lactis NZ9000 in the prevention of intestinal mucositis

Background

Mucositis is one of the most relevant gastrointestinal inflammatory conditions in humans, generated by the use of chemotherapy drugs, such as 5-fluoracil (5-FU). 5-FU-induced mucositis affects 80% of patients undergoing oncological treatment causing mucosal gut dysfunctions and great discomfort. As current therapy drugs presents limitations in alleviating mucositis symptoms, alternative strategies are being pursued. Recent studies have shown that the antimicrobial pancreatitis-associated protein (PAP) has a protective role in intestinal inflammatory processes. Indeed, it was demonstrated that a recombinant strain of Lactococcus lactis expressing human PAP (LL-PAP) could prevent and improve murine DNBS-induced colitis, an inflammatory bowel disease (IBD) that causes severe inflammation of the colon. Hence, in this study we sought to evaluate the protective effects of LL-PAP on 5-FU-induced experimental mucositis in BALB/c mice as a novel approach to treat the disease.

Results

Our results show that non-recombinant L. lactis NZ9000 have antagonistic activity, in vitro, against the enteroinvasive gastrointestinal pathogen L. monocytogenes and confirmed PAP inhibitory effect against Opportunistic E. faecalis. Moreover, L. lactis was able to prevent histological damage, reduce neutrophil and eosinophil infiltration and secretory Immunoglobulin-A in mice injected with 5-FU. Recombinant lactococci carrying antimicrobial PAP did not improve those markers of inflammation, although its expression was associated with villous architecture preservation and increased secretory granules density inside Paneth cells in response to 5-FU inflammation.

Conclusions

We have demonstrated for the first time that L. lactis NZ9000 by itself, is able to prevent 5-FU-induced intestinal inflammation in BALB/c mice. Moreover, PAP delivered by recombinant L. lactis strain showed additional protective effects in mice epithelium, revealing to be a promising strategy to treat intestinal mucositis.

A review of complementary therapies for chemotherapy induced gastrointestinal mucositis

Administration of chemotherapy often leads to gastrointestinal mucositis (GIM). GIM manifests as nausea, abdominal pain and diarrhoea in recipients of chemotherapy. GIM is a major complication occurring in approximately 80% of patients receiving 5-flurouracil treatment. These side-effects may become so severe that significant dose reductions are required, ultimately affecting treatment efficacy and patient survival. Complementary and alternative medicine (CAM) is a growing area of public interest. This review will provide an overview of current knowledge of complementary medicinal therapies for chemotherapy induced GIM. An understanding of this evolving literature is useful in discussing these therapies with patients who are considering using them.

Lactobacillus plantarum NCU116 attenuates cyclophosphamide-induced intestinal mucosal injury, metabolism and intestinal microbiota disorders in mice

Anticancer drugs at high doses often damage the intestinal mucosa and metabolism. Lactobacillus plantarum NCU116 (NCU116) isolated from pickled vegetables was orally given to cyclophosphamide-treated mice to determine its effects on intestinal mucosal injury, nutrient metabolism and colon microbiota, and investigate the mechanisms accounting for its effects. Mice treated with the bacterium were found to favorably recover intestine morphology of villus height and crypt depth, and have improved mucins expression and quantity of goblet cells, as well as intestinal metabolism by increasing the level of short-chain fatty acids and reducing the concentration of ammonia in the colon feces. In addition, NCU116-treated mice showed a higher diversity of colonic microbiota than the group without bacterium supplementation. The number of Lactobacillus and Bifidobacterium in the mouse colon was increased after bacterium intake, which decreased the number of potentially pathogenic bacteria, Escherichia coli and Pseudomonas. These results indicated that NCU116 could be of significant advantage in reducing intestinal mucosal injury and improving the intestinal metabolism and the intestinal microbiota.

Effects of nimesulide on the small intestine mucositis induced by methotrexate in rats

Intestinal mucositis is one of the major problems in the patients receiving cancer treatment. Nimesulide is a drug with antioxidant, antiinflammatory and antiulcer features. We aimed to investigate the effect of nimesulide on the small intestine mucositis induced by methotrexate (MTX) in rats. Experimental animals were divided into the control group, MTX group (MTXG) and nimesulide+MTX administered group (NMTXG) with eight rats per group. The control and MTXG groups were given distilled water by gavage and the NMTXG was given nimesulide 100 mg/kg orally. After one hour, the NMTXG and MTXG rat groups were administered oral MTX 5 mg/kg. This procedure was repeated once a day for 15 days and the rats were sacrificed. The duodenum and jejunum of each rat was removed for the assessment of biochemical markers and histopathological evaluation. Malondialdehyde (MDA) and myeloperoxidase (MPO) levels were significantly higher in the duodenal and jejunal tissues of the animals which received MTX, compared to the control and NMTXG (P<0.001). Also, the levels of total glutathione (tGSH), glutathione reductase (GSHRd), glutathione peroxidase (GSHPx), catalase (CAT) and superoxide dismutase (SOD) were significantly lower in the MTXG (P<0.001) compared to other groups. MTX led to villus and crypt epithelial damage and inflammation containing marked PMNL and eosinophils in the intestinal tissues histopathologically. Whereas, there was only mild irregularities in the villus structures of the NMTXG. Nimesulide protected the small intestines against damage by MTX. Intestinal mucositis caused by MTX may be preventable by co-administered nimesulide.

Probiotic Pediococcus pentosaceus strain GS4 alleviates azoxymethane-induced toxicity in mice

Probiotic treatment has been gaining attention due to its remarkable effects in alleviating toxicity and carcinogenesis. The novel strain Pediococcus pentosaceus GS4 has been reported for probiotic, survivability in simulated gastrointestinal fluid, and antioxidative and biohydrogenation properties. Therefore, we hypothesize that this specific strain might be able to assuage the effect of azoxymethane (AOM)-induced toxicity in mice. Twenty-eight Swiss albino mice were divided into 4 groups and were studied for 32 weeks. Azoxymethane (10 mg/kg body weight) was administered intraperitoneally twice (0th and 14th days), and probiotic GS4 (1.1 × 10(9) colony-forming unit/mL) was given orally for the respective groups. Mice who served as the normal control received only normal saline. GS4-intervened AOM-induced mice showed marked improvement at the histopathologic level, in the liver and kidney. Moreover, probiotic GS4 intervention in AOM-induced mice exhibited a significant reduction in the liver function biomarker when compared with the AOM-induced mice. Probiotic GS4 intervention reduced the intestinal structural deformities as evident from the elevated brush border membrane-associated disaccharidases (sucrase, lactase) and intestinal alkaline phosphatase activities, which were found disrupted by AOM intoxication. Fecal bacterial load was found to be reduced in AOM-induced mice which were subsequently replenished by the probiotic GS4 intervention as apparent from the enhanced fecal bacterial load. There were no adverse effects observed in the probiotic control group. Conclusively, novel probiotic strain GS4 exhibited safe and beneficial effects against the toxicity threats posed by AOM. Thus, GS4 could be considered as a potential food supplement/additive for therapeutic purposes in gastrointestinal disorders related to inflammation and cancer.

Bovine Colostrum Modulates Myeloablative Chemotherapy-Induced Gut Toxicity in Piglets

BACKGROUND

Intensive chemotherapy frequently results in gut toxicity, indicated by oral and intestinal mucositis, resulting in poor treatment outcomes and increased mortality. There are no effective preventive strategies against gut toxicity and the role of diet is unknown.

OBJECTIVE

We hypothesized that the severity of chemotherapy-induced gut toxicity in early life is diet-dependent, and that intake of bovine colostrum (BC) provides better gut protection than an artificial milk replacer (MR).

METHODS

A total of 37 3-d-old pigs received for 6 d either intravenous saline control or myeloablative treatment with busulfan and cyclophosphamide, and were fed either BC or MR, resulting in the following 4 treatments (n = 8-10/group): bovine colostrum plus saline control (Ctr-BC), milk replacer plus saline control (Ctr-MR), bovine colostrum plus busulfan and cyclophosphamide chemotherapy (BUCY-BC), and milk replacer plus busulfan and cyclophosphamide chemotherapy (BUCY-MR). The gut was collected for analysis 11 d after the start of chemotherapy.

RESULTS

Relative to the control groups, both busulfan and cyclophosphamide chemotherapy (BUCY) groups showed signs of gut toxicity, with oral ulcers, reduced intestinal dimensions, and hematologic toxicity. Diet type did not affect mucosal structure on day 11, but BUCY-BC pigs had less vomiting than BUCY-MR pigs (1 of 10 vs. 10 of 10, P < 0.05). Markers of intestinal function were higher (up to 20-fold greater galactose absorption and 2-3-fold greater brush border enzyme activity, all P < 0.05), and tissue inflammatory cytokine concentrations and serum liver enzyme values were lower in BUCY-BC than in BUCY-MR pigs (30-50% reductions in interleukin 6 and 8, aminotransferase, and bilirubin concentrations, P < 0.05). Gut colonization was not significantly affected except that BUCY pigs had lower microbial diversity with a higher abundance of Lactobacilli.

CONCLUSION

BC may reduce gut toxicity during myeloablative chemotherapy in piglets by preserving intestinal function and reducing inflammation. Whether similar effects occur in children remains to be tested.

Mucosal barrier injury, fever and infection in neutropenic patients with cancer: introducing the paradigm febrile mucositis

Infection remains one of the most prominent complications after cytotoxic treatment for cancer. The connection between neutropenia and both infections and fever has long been designated as 'febrile neutropenia', but treatment with antimicrobial agents and haematopoietic growth factors has failed to significantly reduce its incidence. Moreover, emerging antimicrobial resistance is becoming a concern that necessitates the judicious use of available antimicrobial agents. In addition to neutropenia, patients who receive cytotoxic therapy experience mucosal barrier injury (MBI) or 'mucositis'. MBI creates a port-de-entrée for resident micro-organisms to cause blood stream infections and contributes directly to the occurrence of fever by disrupting the highly regulated host-microbe interactions, which, even in the absence of an infection, can result in strong inflammatory reactions. Indeed, MBI has been shown to be a pivotal factor in the occurrence of inflammatory complications after cytotoxic therapy. Hence, the concept 'febrile neutropenia' alone may no longer suffice and a new concept 'febrile mucositis' should be recognized as the two are at least complementary. This review we summarizes the existing evidence for both paradigms and proposes new therapeutic approaches to tackle the perturbed host-microbe interactions arising from cytotoxic therapy-induced tissue damage in order to reduce fever in neutropenic patients with cancer.

Protective effect of amifostine on high-dose methotrexate-induced small intestinal mucositis in mice

BACKGROUND

Amifostine has been shown to be capable of minimizing radiotherapy-induced oral mucositis, but whether it protects small intestinal mucosae from high-dose methotrexate-induced damage is presently unknown.

AIM

We aimed to evaluate the protective effect of amifostine against high-dose methotrexate-induced small intestinal mucositis and its mechanism.

METHODS

Ninety Kunming mice were randomly divided into five experimental groups: saline control; high-dose methotrexate (HDMTX) group: treated with a single high dose of methotrexate; calcium folinate (CF) group: treated with high-dose methotrexate followed with CF; Amifostine group: treated with amifostine, followed with high-dose methotrexate; and amifostine-CF group: treated with amifostine pre-high-dose methotrexate and followed by CF post-high-dose methotrexate. Mouse weight, villus height and crypt depth, stool consistency, white blood cell count, death and survival were recorded. Bax and Bcl-2 mRNA expression were quantified by semi-quantitative PCR.

RESULTS

Compared to the mice treated with HDMTX, CF, and amifostine, mice treated with Amifostine-CF group were heavier and had greater villus height, crypt depth, and normal white blood cell count and lower diarrhea rate and mortality than the HDMTX, CF and amifostine groups. There was a significant decrease in enterocyte apoptosis in amifostine-CF mice compared with the HDMTX and CF groups.

CONCLUSIONS

The effect of amifostine plus CF was greater than amifostine or CF alone in preventing high-dose methotrexate-induced intestinal mucositis and improving intestinal recovery in mice.

Oral Administration of the Probiotic Lactobacillus casei Ameliorates Gut Morphology and Physiology in Malnourished-Giardia intestinalis-Infected BALB/c Mice

Malnutrition reduces the host immunity and enhances the host susceptibility to various diseases. The present study describes the effect of oral administration of probiotic Lactobacillus casei to malnourished-Giardia-infected BALB/c mice with respect to surface alterations and brush border membrane enzyme activity of the small intestine. It was observed that probiotic feeding either prior to or simultaneously with Giardia infection to malnourished mice led to significantly enhanced activity of disaccharidases compared with malnourished and Giardia-infected mice. Scanning electron microscopy also revealed less mucosal damage in the villi of small intestine of probiotic-fed malnourished-Giardia-infected mice compared with completely damaged, mummified, or blunted villi of malnourished-Giardia-infected mice. The findings indicate that probiotics can be used as the prophylactic candidate in abrogating the gut and intestinal dissacharidases anamolies in malnourished hosts suffering from the intestinal diseases.

Lactobacillus rhamnosus GG antagonizes Giardia intestinalis induced oxidative stress and intestinal disaccharidases: an experimental study

The present study describes the in vivo modulatory potential of Lactobacillus rhamnosus GG (LGG), an effective probiotic, in Giardia intestinalis-infected BALB/c mice. Experimentally, it was observed that oral administration of lactobacilli prior or simultaneous with Giardia trophozoites to mice, efficiently (p < 0.05) reduced both the severity and duration of giardiasis. More specifically, probiotics fed, Giardia-infected mice, showed a significant increase in the levels of antioxidants [reduced glutathione (GSH) and superoxide dismutase (SOD)] and intestinal disaccharidases [sucrase and lactase] and decreased levels of oxidants in the small intestine, in comparison with Giardia-infected mice. Histopathological findings also revealed almost normal cellular morphology of the small intestine in probiotic-fed Giardia-infected mice compared with fused enterocytes, villous atrophy and increased infiltration of lymphocytes in Giardia-infected mice. The results of the present study has shed new light on the anti-oxidative properties of LGG in Giardia mediated tissue injury, thereby suggesting that the effects of probiotic LGG are biologically plausible and could be used as an alternative microbial interference therapy.

Evidence supporting the use of probiotics for the prevention and treatment of chemotherapy-induced intestinal mucositis

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.

Effect of lactobacilli on paracellular permeability in the gut

Paracellular permeability is determined by the complex structures of junctions that are located between the epithelial cells. Already in 1996, it was shown that the human probiotic strain Lactobacillus plantarum 299v and the rat-originating strain Lactobacillus reuteri R2LC could reduce this permeability in a methotrexate-induced colitis model in the rat. Subsequently, many animal models and cell culture systems have shown indications that lactobacilli are able to counteract increased paracellular permeability evoked by cytokines, chemicals, infections, or stress. There have been few human studies focusing on the effect of lactobacilli on intestinal paracellular permeability but recently it has been shown that they could influence the tight junctions. More precisely, short-term administration of L. plantarum WCSF1 to healthy volunteers increased the relocation of occludin and ZO-1 into the tight junction area between duodenal epithelial cells.

Intervention of alpha-lipoic acid ameliorates methotrexate-induced oxidative stress and genotoxicity: A study in rat intestine

Methotrexate (MTX) is an anti-metabolite, widely used in the cancer chemotherapy and rheumatoid arthritis. However, its long-term clinical use is restricted on account of its severe intestinal toxicity. The present study was aimed to investigate the intestinal toxicity of MTX and the possible protective effect of alpha-lipoic acid (LA) on Sprague-Dawley rats. MTX-induced intestinal toxicity was evaluated at the dose of 2.5mg/kg for short-term (5 days treatment) and 1mg/kg for long-term (5 days in a week for four consecutive weeks treatment) study. The possible protective effect of LA was evaluated in both short- as well as long-term study in a dose-dependent manner. MTX treatment induced diarrhoea and mortality in rats, indicating its severe toxicity in the target organ of investigation, i.e., intestine. Further, the intestinal toxicity of MTX was assessed by evaluating different parameters of oxidative stress, DNA damage, cytotoxicity as well as histological changes. Immunostaining for p53 revealed higher genotoxic assault in the intestinal cells due to MTX treatment. Pretreatment of rats with LA led to significant decrease in the oxidative stress, DNA damage, cellular damage, inflammatory changes and apoptosis as determined by malondialdehyde level, glutathione level, comet assay parameters, histological evaluation, immunostaining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. In the present investigation, we report that LA pretreatment ameliorates MTX-induced intestinal toxicity in rat as evident from the protection against oxidative stress, decrease in DNA damage and protection of cellular morphology as well as improvement in the stool consistency and animal survival rate.