Amelioration of Chemotherapy-Induced Intestinal Mucositis by Orally Administered Probiotics in a Mouse Model

Background and Aims

Intestinal mucositis is a frequently encountered side effect in oncology patients undergoing chemotherapy. No well-established or up to date therapeutic strategies are available. To study a novel way to alleviate mucositis, we investigate the effects and safety of probiotic supplementation in ameliorating 5-FU-induced intestinal mucositis in a mouse model.

Methods

Seventy-two mice were injected saline or 5-Fluorouracil (5-FU) intraperitoneally daily. Mice were either orally administrated daily saline, probiotic suspension of Lactobacillus casei variety rhamnosus (Lcr35) or Lactobacillus acidophilus and Bifidobacterium bifidum (LaBi). Diarrhea score, pro-inflammatory cytokines serum levels, intestinal villus height and crypt depth and total RNA from tissue were assessed. Samples of blood, liver and spleen tissues were assessed for translocation.

Results

Marked diarrhea developed in the 5-FU groups but was attenuated after oral Lcr35 and LaBi administrations. Diarrhea scores decreased significantly from 2.64 to 1.45 and 0.80, respectively (P<0.001). Those mice in 5-FU groups had significantly higher proinflammatory cytokine levels (TNF-α: 234.80 vs. 29.10, P<0.001, IL-6: 25.13 vs. 7.43, P<0.001, IFN-γ: 22.07 vs. 17.06, P = 0.137). A repairing of damage in jejunal villi was observed following probiotics administration. We also found TNF-α, IL-1β and IL-6 mRNA expressions were up-regulated in intestinal mucositis tissues following 5-FU treatment (TNF-α: 4.35 vs. 1.18, IL-1β: 2.29 vs. 1.07, IL-6: 1.49 vs. 1.02) and that probiotics treatment suppressed this up-regulation (P<0.05). No bacterial translocation was found in this study.

Conclusions

In conclusion, our results show that oral administration of probiotics Lcr35 and LaBi can ameliorate chemotherapy-induced intestinal mucositis in a mouse model. This suggests probiotics may serve as an alternative therapeutic strategy for the prevention or management of chemotherapy-induced mucositis in the future.     

Intestinal Distribution and Intraluminal Localization of Orally Administered Clostridium butyricum in Rats

Clostridium butyricum has been used as a probiotic in animals and humans for years, however, its fate in the intestine has not been clarified yet. We investigated the intestinal fate of C. butyricum using a selective medium and a monoclonal antibody after orally administering C. butyricum spores to rats. The number of C. butyricum, both viable and dead cells, in the intestinal contents were counted by enzyme-linked immunosorbent assay (ELISA) at various times after a single oral administration. The total viable number of C. butyricum was counted using a selective medium, and viable resting spores were selectively detected by treating the samples with ethanol. To investigate the intraluminal localization of the C. butyricum cells, frozen intestinal tracts were imprinted onto slides and stained with immunogold-silver. Total viable spores exceeded the number of viable resting spores by more than 10-fold from the proximal to middle of the small intestine 30 min after administration. Vegetative cells of C. butyricum were first detected in the distal small intestine after 2 hr, and vegetative growth was observed from the cecum to the colon 5 hr after administration. Dead vegetative cells were detected 9 hr after administration, and C. butyricum cells were not detected in the intestine after 3 days. The C. butyricum cells in the intestinal imprints were stained specifically by immunogold-silver staining, and proliferative cells were observed in the cecum after 3 hr. These results suggest that the administered C. butyricum germinated in the upper small intestine, grew mainly from the distal small intestine to the colon and were excreted from the rat intestine within 3 days.     

合生元益生菌冲剂对小鼠肠道菌群调节作用的研究

目的 研究合生无益生菌冲剂对小鼠肠道菌群的调节作用.方法 将小鼠分为阴性对照组、合生元益生菌冲剂组.阴性对照组灌服蒸馏水14 d,合生元益生菌冲剂组灌服1 g/kg·d剂量的台生元益生菌冲剂14 d,检测实验前后肠道菌群数量.结果 灌服后小鼠肠道菌群与灌服前比较,,双歧杆菌数量有显著性增加（P＜0.05）,肠杆菌、肠球菌、乳杆菌和产气荚膜梭菌数量有无显著性变化（P＞0.05）.结论 合生元益生菌冲剂对小鼠肠道菌群具有一定的调节作用.     

鼠伤寒沙门氏菌诱导昆明小鼠肠道感染模型的建立

目的:建立鼠伤寒沙门氏菌诱导昆明小鼠肠道感染模型。方法:先用5 mg/mL链霉素预处理2 d,提高小鼠对鼠伤寒沙门氏菌的敏感性,然后正常饲养1 d,攻毒前禁水禁食4 h,再分别以不同剂量灌胃攻毒2次,间隔24 h。观察小鼠临床症状,并通过组织病理切片、透射电镜和免疫组织化学的方法,分别观察小鼠肠道组织病理变化、小肠上皮细胞超微结构变化及肠道淋巴细胞增殖状况。结果:攻毒后昆明小鼠会出现昏睡、食欲不振、寒颤,甚至死亡的现象,解剖后发现小鼠肠道充血膨胀。组织病理切片显示小鼠肠粘膜受损,小肠绒毛肿胀,排列杂乱,炎性细胞浸润;透射电镜观察超微结构显示小肠上皮细胞线粒体空泡化,嵴和膜发生融合消失,粗面内质网发生扩张;免疫组织化学的方法显示肠道感染后,淋巴结肿大,T淋巴细胞大量增殖。结论:该模型对探索鼠伤寒沙门氏菌引发肠炎的发病机制、病理生理、免疫等方面作用具有重要意义,并为特异性卵黄抗体被动免疫保护效果的后续评价奠定基础。     

Simplified Intestinal Microbiota to Study Microbe-Diet-Host Interactions in a Mouse Model

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Teratogenicity and Embryotoxicity of Orally Administered Fenchlorphos in Blue Foxes

Pregnant blue foxes (Alopex lagopus) were administered fenchlorphos (0-0-dimethyl-0-(2,4,5-trichlorophenyl) phos-phorothioate) orally at a dose of 100 mg/kg/day in different periods of gestation. The dose chosen represents the therapeutic dose for the treatment of parasitic lesions. At term the mean number of whelps were recorded, and they were killed and examined for external, visceral and skeletal malformations. Of 19 medicated vixens the mean number of live whelps at term was 1.2 per vixen versus 9.5 in the control group. There was an evident predominance of males in the medicated groups. Several malformations of the head were registered, among them incomplete ossification of the skull bones, cleft palate, hydrocephalus internus and externus. Minor malformations like extra ribs or missing ribs occurred in the medicated groups. Congenital alopecia, hypoplastic kidneys, and hydronephrosis were observed in all the whelps in 1 medicated group. No significant difference in total brain weight, cerebellum weight or the cerebellum-to-total-brain weight was observed. Histological examination of the cerebellum showed a narrowing or absence of the granular and the molecular layers of the cortical zone.     

Continuous Orally Administered Coffee Enhanced the Antigen-Specific Th1 Response and Reduced Allergic Development in a TCR-Transgenic Mice Model

Coffee is a globally consumed beverage. Although recent studies have suggested that coffee reduced the risk of lifestyle-related diseases, there are few studies regarding allergic response.

This study investigates the effects of orally administered coffee (91 ml/kg/d) on allergic responses using a T cell receptor (TCR)-transgenic DO11.10 mouse allergic model. Splenocytes from coffee-administered naïve mice increased antigen (Ag)-specific interleukin (IL)-12p40 secretion. When Ag sensitization and coffee administration were concurrently performed, the splenocytes from coffee-administered mice showed a decrease of IL-2 and an increase of IL-12p40 secretion. The Ag-specific cutaneous response and serum IgE level were reduced in coffee-administered mice, although, after establishing the allergy, coffee administration did not suppress the allergic reaction.

These results suggest that coffee could induce a Th1-type response of the immune system and prevent an allergy developing. Further studies on the optimum dose, cultivar differences, and roasted degree need to be undertaken.     

Effects of Orally Administered Tetracycline on the Intestinal Community Structure of Chickens and on tet Determinant Carriage by Commensal Bacteria and Campylobacter jejuni

There is a growing concern that antibiotic usage in animal production has selected for resistant food-borne bacteria. Since tetracyclines are common therapeutic antibiotics used in poultry production, we sought to evaluate the effects of oral administration on the resistance of poultry commensal bacteria and the intestinal bacterial community structure. The diversity indices calculated from terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA amplicons did not indicate significant changes in the cecal bacterial community in response to oxytetracycline. To evaluate its effects on cultivable commensals, Enterococcus spp., Escherichia coli, and Campylobacter spp. were isolated from the cecal droppings of broiler chickens. Enterococcus spp. and E. coli expressed tetracycline MICs of >8 μg/ml and harbored a variety of tet resistance determinants regardless of the tetracycline exposure history of the birds. The enterococcal isolates possessed tetM (61%), tetL (25.4%), and tetK (1.3%), as well as tetO (52.5%), the determinant known to confer a tetracycline resistance phenotype in Campylobacter jejuni. E. coli isolates harbored tetA (32.2%) or tetB (30.5%). Tetracycline MICs remained at <2 μg/ml for Campylobacter isolates before and after tetracycline treatment of the chickens, even though isolates expressing MICs of >16 μg/ml were commonly cultured from flocks that did not receive oxytetracycline. The results imply that complex ecological and genetic factors contribute to the prevalence of antibiotic resistance arising from resistance gene transfer in the production environment.     

Oral Administered Particulate Yeast-Derived Glucan Promotes Hepatitis B Virus Clearance in a Hydrodynamic Injection Mouse Model

Hepatitis B virus (HBV) persistent infection is associated with ineffective immune response for the clearance of virus. Immunomodulators represent an important class of therapeutics, which potentially could be beneficial for the treatment of HBV infection. The particulate yeast-derived glucan (PYDG) has been shown to enhance the innate and adaptive immune responses. We therefore, assessed the efficacy of PYDG in enhancing HBV specific immune responses by employing the hydrodynamic injection-based (HDI) HBV transfection mouse model. Mice were intragatric administered PYDG daily for 9 weeks post pAAV/HBV1.2 hydrodynamic injection. PYDG treatment significantly promoted HBV DNA clearance and production of HBsAb compared to control mice. PYDG treatment resulted in recruitment of macrophages, dendritic cells (DCs) and effector T cells to the liver microenvironment, accompanied by a significantly augmented DCs maturation and HBV-specific IFN-γ and TNF-α production by T cell. In addition, enhanced production of Th1 cytokines in liver tissue interstitial fluid (TIF) was associated with PYDG administration. Live imaging showed the accumulation of PYDG in the mouse liver. Our results demonstrate that PYDG treatment significantly enhances HBV-specific Th1 immune responses, accompanied by clearance of HBV DNA, and therefore holds promise for further development of therapeutics against chronic hepatitis B.     

Deregulated Lipid Sensing by Intestinal CD36 in Diet-Induced Hyperinsulinemic Obese Mouse Model

The metabolic syndrome (MetS) greatly increases risk of cardiovascular disease and diabetes and is generally associated with abnormally elevated postprandial triglyceride levels. We evaluated intestinal synthesis of triglyceride-rich lipoproteins (TRL) in a mouse model of the MetS obtained by feeding a palm oil-rich high fat diet (HFD). By contrast to control mice, MetS mice secreted two populations of TRL. If the smaller size population represented 44% of total particles in the beginning of intestinal lipid absorption in MetS mice, it accounted for only 17% after 4 h due to the secretion of larger size TRL. The MetS mice displayed accentuated postprandial hypertriglyceridemia up to 3 h due to a defective TRL clearance. These alterations reflected a delay in lipid induction of genes for key proteins of TRL formation (MTP, L-FABP) and blood clearance (ApoC2). These abnormalities associated with blunted lipid sensing by CD36, which is normally required to optimize jejunal formation of large TRL. In MetS mice CD36 was not downregulated by lipid in contrast to control mice. Treatment of controls with the proteosomal inhibitor MG132, which prevented CD36 downregulation, resulted in blunted lipid-induction of MTP, L-FABP and ApoC2 gene expression, as in MetS mice. Absence of CD36 sensing was due to the hyperinsulinemia in MetS mice. Acute insulin treatment of controls before lipid administration abolished CD36 downregulation, lipid-induction of TRL genes and reduced postprandial triglycerides (TG), while streptozotocin-treatment of MetS mice restored lipid-induced CD36 degradation and TG secretion. In vitro, insulin treatment abolished CD36-mediated up-regulation of MTP in Caco-2 cells. In conclusion, HFD treatment impairs TRL formation in early stage of lipid absorption via insulin-mediated inhibition of CD36 lipid sensing. This impairment results in production of smaller TRL that are cleared slowly from the circulation, which might contribute to the reported association of CD36 variants with MetS risk.     

低聚半乳糖对肠道益生菌产胞外多糖作用的研究

旨在研究低聚半乳糖对肠道益生菌产胞外多糖的作用。以低聚半乳糖、葡萄糖、半乳糖和乳糖4种碳源作比较,分别从碳源的利用、胞外多糖的产量和种类及其对有害菌的黏附作用进行研究。结果显示,低聚半乳糖不仅能促进长双歧杆菌和植物乳杆菌的增殖,而且有利于胞外多糖的产生,其含量分别为208.78μg/m L和192.78μg/m L,产生的胞外多糖种类较其他3种碳源更多,对肠道有害菌大肠杆菌具有明显黏附作用。结果证明,与其他3种碳源相比,低聚半乳糖能促进植物乳杆菌和两歧双歧杆菌生成更多的胞外多糖。     

Treatment of Type 2 Diabetes Mellitus With Orally Administered Agents: Advances in Combination Therapy

ObjectiveTo discuss the effects and clinical benefit provided by combining various orally administered antidiabetic drugs (OADs) for the treatment of type 2 diabetes and to examine the advantages of single-tablet combinations with respect to targeting hyperglycemia and adherence.MethodsA review of randomized controlled trials that studied OAD combinations for the treatment of type 2 diabetes was conducted by using search terms in PubMed.ResultsReported data have documented that OAD combination therapies have additional benefits over monotherapy in terms of glycemic efficacy. Results from randomized controlled trials on a range of OAD combinations have demonstrated differences in safety and efficacy. The use of single-tablet OAD combinations has been shown to improve adherence in patients.ConclusionThe development of single-tablet OAD combinations that can address all aspects of glycemia with a favorable tolerability profile has the potential to help patients manage their glycemic control more effectively and to minimize the risk of long-term diabetes-related complications. In addition, single-tablet combinations of agents offer improved convenience for patients as well as potential cost benefits. Thus, they represent an important treatment option for type 2 diabetes. (Endocr Pract. 2009;15:750-762)     

Effects of Orally Administered Bovine Lactoperoxidase on Dextran Sulfate Sodium-Induced Colitis in Mice

The effect of lactoperoxidase (LPO) on dextran sulfate sodium-induced colitis was examined in mice. After 9 d of colitis induction, weight loss, colon shortening, and the histological score were significantly suppressed in mice orally administered LPO (62.5 mg/body/d) as compared to a group administered bovine serum albumin. These results suggest that LPO exhibits anti-inflammatory effects in the gastrointestinal tract.     

Recovery of Cognitive Dysfunction via Orally Administered Redox-Polymer Nanotherapeutics in SAMP8 Mice

Excessively generated reactive oxygen species are associated with age-related neurodegenerative diseases. We investigated whether scavenging of reactive oxygen species in the brain by orally administered redox nanoparticles, prepared by self-assembly of redox polymers possessing antioxidant nitroxide radicals, facilitates the recovery of cognition in 17-week-old senescence-accelerated prone (SAMP8) mice. The redox polymer was delivered to the brain after oral administration of redox nanoparticles via a disintegration of the nanoparticles in the stomach and absorption of the redox polymer at small intestine to the blood. After treatment for one month, levels of oxidative stress in the brain of SAMP8 mice were remarkably reduced by treatment with redox nanoparticles, compared to that observed with low-molecular-weight nitroxide radicals, resulting in the amelioration of cognitive impairment with increased numbers of surviving neurons. Additionally, treatment by redox nanoparticles did not show any detectable toxicity. These findings indicate the potential of redox polymer nanotherapeutics for treatment of the neurodegenerative diseases.