The role of probiotic cultures in the prevention of colon cancer

Unraveling the Gut Microbiota: Implications for Precision Nutrition and Personalized Medicine

Recent studies have shown a growing interest in the complex relationship between the human gut microbiota, metabolism, and overall health. This review aims to explore the gut microbiota-host association, focusing on its implications for precision nutrition and personalized medicine. The objective is to highlight how gut microbiota modulate metabolic and immune functions, contributing to disease susceptibility and wellbeing. The review synthesizes recent research findings, analyzing key studies on the influence of gut microbiota on lipid and carbohydrate metabolism, intestinal health, neurobehavioral regulation, and endocrine signaling. Data were drawn from both experimental and clinical trials examining microbiota-host interactions relevant to precision nutrition. Our findings highlight the essential role of gut microbiota-derived metabolites in regulating host metabolism, including lipid and glucose pathways. These metabolites have been found to influence immune responses and gut barrier integrity. Additionally, the microbiota impacts broader physiological processes, including neuroendocrine regulation, which could be crucial for dietary interventions. Therefore, understanding the molecular mechanisms of dietary-microbiota-host interactions is pivotal for advancing personalized nutrition strategies. Tailored dietary recommendations based on individual gut microbiota compositions hold promise for improving health outcomes, potentially revolutionizing future healthcare approaches across diverse populations.

Neuroprotective Effects of Probiotic Lactobacillus reuteri GMNL-263 in the Hippocampus of Streptozotocin-Induced Diabetic Rats

Diabetes-related brain complications have been reported in clinical patients and experimental models. The objective of the present study was to investigate the neuroprotective mechanisms of Lactobacillus reuteri GMNL-263 in streptozotocin (STZ)-induced diabetic rats. In this study, three different groups, namely control group, STZ-induced (55 mg/kg streptozotocin intraperitoneally) diabetic rats (DM), and DM rats treated with Lactobacillus reuteri GMNL-263 (1 × 109 CFU/rat/day), were utilized to study the protective effect of GMNL-263 in the hippocampus of STZ-induced diabetic rats. The results demonstrated that GMNL-263 attenuated diabetes-induced hippocampal damage by enhancing the cell survival pathways and repressing both inflammatory and apoptotic pathways. Histopathological analysis revealed that GMNL-263 prevented structural changes in the hippocampus in the DM group and decreased the level of inflammation and apoptosis in the hippocampus of DM rats. The IGF1R cell survival signaling pathway also improved after GMNL-263 treatment. These results indicate that probiotic GMNL-263 exerts beneficial effects in the brain of diabetic rats and has potential ability for clinical application.

Targeted lactate dehydrogenase genes silencing in probiotic lactic acid bacteria: A possible paradigm shift in colorectal cancer treatment?

Even though the pathophysiology of colorectal cancer (CRC) is complicated and poorly understood, interactions between risk factors appear to be key in the development and progression of the malignancy. The popularity of using lactic acid bacteria (LAB) prebiotics and probiotics to modulate the tumor microenvironment (TME) has grown widely over the past decade. The objective of this study was therefore to determine the detrimental effects of LAB-derived lactic acid in the colonic mucosa in colorectal cancer management. Six library databases and a web search engine were used to execute a structured systematic search of the existing literature, considering all publications published up until August 2022. A total of 7817 papers were screened, all of which were published between 1995 and August 2022. However, only 118 articles met the inclusion criterion. Lactic acid has been directly linked to the massive proliferation of cancerous cells since the glycolytic pathway provides cancerous cells with not only ATP, but also biosynthetic intermediates for rapid growth and proliferation. Our research suggests that targeting LAB metabolic pathways is capable of suppressing tumor growth and that the LDH gene is critical for tumorigenesis. Silencing of Lactate dehydrogenase, A (LDHA), B (LDHB), (LDHL), and hicD genes should be explored to inhibit fermentative glycolysis yielding lactic acid as the by-product. More studies are necessary for a solid understanding of this topic so that LAB and their corresponding lactic acid by-products do not have more adverse effects than their widely touted positive outcomes in CRC management.

Growth kinetics of probiotic lactobacilli strains cultivated in a laboratory bioreactor with stirring

Batch cultivation in a laboratory bioreactor with stirring of the lactobacilli strains with probiotic properties Lacticaseibacillus casei ssp. casei G17 and Lacticaseibacillus casei ssp. rhamnosus G16 isolated from pink blossom of Rosa damascena Mill was conducted. The changes in the concentration of viable cells were monitored. The growth kinetics was modeled applying the classic and modified logistic curve model and the maximum specific growth rate (μm) of the studied strains was determined. The classical model of the logistic curve showed higher μm for Lacticaseibacillus casei ssp. casei G17 - 0.133 h-1, compared to Lacticaseibacillus casei ssp. rhamnosus G16 - 0.120 h-1, while the modified logistic curve model predicted comparable maximum growth rates of 0.105 h-1 and 0.101 h-1 for Lacticaseibacillus casei ssp. casei G17 and Lacticaseibacillus casei ssp. rhamnosus G16, respectively. Lacticaseibacillus casei ssp. casei G17 was characterized by a shorter induction period (τa = 0.72 h) and a higher adaptation rate constant (k0 – 0.390 h-1) compared to Lacticaseibacillus casei ssp. rhamnosus G16 (τa=1.66 h; k0=0.110 h-1). The established kinetic parameters show that Lacticaseibacillus casei ssp. rhamnosus G16 needs the addition of growth factors in the fermentation medium that will help to optimize its composition for scaling up the fermentation process.

Hyperglycemia-Induced Cardiac Damage Is Alleviated by Heat-Inactivated Lactobacillus reuteri GMNL-263 via Activation of the IGF1R Survival Pathway

Diabetes-induced cardiomyocyte apoptosis is one of the major causes of mortality in patients with diabetes. Numerous studies have indicated the beneficial effects of Lactobacillus reuteri GMNL-263. However, the protective effect of Lactobacillus reuteri GMNL-263 in cardiac damage associated with diabetes remains poorly understood. In this study, we aimed to investigate the protective effect of Lactobacillus reuteri GMNL-263 on cardiomyocytes in diabetic rats. Five-week-old male Wistar rats were categorized into normal control group, diabetes group (55 mg/kgw STZ-induced diabetes via intraperitoneal injection), and diabetic animals treated with Lactobacillus reuteri GMNL-263 (10⁹ CFU/rat/day, oral administration for 4 weeks). The results were presented that oral administration of a high dose of Lactobacillus reuteri GMNL-263 in diabetic rats activated IGF1R cell survival pathways to decrease the Fas-dependent and mitochondrial-dependent apoptotic pathways induced by hyperglycemia. We found that GMNL-263 significantly attenuated cell apoptosis via the IGF1R survival pathway in diabetic rats. The findings of this study suggest that GMNL-263 treatment maybe an effective therapeutic approach for the prevention of cardiac apoptosis in patients with diabetes.

Effect of diet and intestinal AhR expression on fecal microbiome and metabolomic profiles

BACKGROUND

Diet, loss of aryl hydrocarbon receptor (AhR) expression and their modification of the gut microbiota community composition and its metabolites affect the development of colorectal cancer (CRC). However, the concordance between fecal microbiota composition and the fecal metabolome is poorly understood. Mice with specific AhR deletion (AhRKO) in intestinal epithelial cell and their wild-type littermates were fed a low-fat diet or a high-fat diet. Shifts in the fecal microbiome and metabolome associated with diet and loss of AhR expression were assessed. Microbiome and metabolome data were integrated to identify specific microbial taxa that contributed to the observed metabolite shifts.

RESULTS

Our analysis shows that diet has a more pronounced effect on mouse fecal microbiota composition than the impact of the loss of AhR. In contrast, metabolomic analysis showed that the loss of AhR in intestinal epithelial cells had a more pronounced effect on metabolite profile compared to diet. Integration analysis of microbiome and metabolome identified unclassified Clostridiales, unclassified Desulfovibrionaceae, and Akkermansia as key contributors to the synthesis and/or utilization of tryptophan metabolites.

CONCLUSIONS

Akkermansia are likely to contribute to the synthesis and/or degradation of tryptophan metabolites. Our study highlights the use of multi-omic analysis to investigate the relationship between the microbiome and metabolome and identifies possible taxa that can be targeted to manipulate the microbiome for CRC treatment.

In vitro screening of probiotic properties of Lactobacillus plantarum isolated from fermented milk product

Objectives

The screening of traditional fermented products is essential for the assessment of safety, security, and further development of functional foods for the well-being of human health. The aim of the present study was to isolate and identify bacteria from fermented raw milk samples that exhibit health benefits upon consumption.

Methods

In order to confirm the isolates as probiotics, several in vitro assays were conducted to assess the probiotic properties of isolated bacteria. The initial screening includes tolerance to acid, bile, pancreatin, and NaCl. The cell surface properties demonstrate their interaction with mucosal epithelium, which includes hydrophobicity and auto-aggregation assay. Safety assessment was done by performing haemolytic test and antibiotic susceptibility test. The antagonistic activity of probiotic strain was further evaluated against some pathogenic bacteria.

Results

Lactobacillus plantarum (L. plantarum) isolated from fermented raw milk was preliminarily identified by biochemical tests and further confirmed using 16S rRNA identification. The isolate designated as L. plantarum strain GCC_19M1 demonstrated significant tolerance to low pH, 0.3% bile, 0.5% pancreatin, and 5% NaCl. In the presence of simulated gastric juice (at pH 3), the isolate exhibited a survival rate of 93.48–96.97%. Furthermore, the development of ecological niches in the human gut and their successful accumulation have been revealed by auto-aggregation and hydrophobicity properties. Absence of haemolytic activity ensures the non-virulent nature of the strain. Lactobacillus plantarum strain GCC_19M1 showed susceptibility towards gentamicin, tetracycline, kanamycin, meropenem, and ceftriaxone and exhibited an antagonistic effect on pathogenic bacteria.

Conclusion

The obtained results conveyed that L. plantarum strain GCC_19M1 has strong probiotic potential, and its presence in the fermented raw milk products may serve as a potent functional probiotic food.

Anti-inflammatory and Antioxidant Properties of Probiotic Bacterium Lactobacillus mucosae AN1 and Lactobacillus fermentum SNR1 in Wistar Albino Rats

The potent antioxidant probiotic strains Lactobacillus mucosae AN1 and Lactobacillus fermentum SNR1 were assessed for anti-inflammatory properties in carrageenan (acute) and complete Freund’s adjuvant-induced inflammation (chronic) models in the present study. The two probiotic strains were administered orally along with feed to the Wistar albino male rats as whole cell as well as microencapsulated form. The following experiments were performed to evaluate the anti-inflammatory properties of probiotic strains and the results were observed that the encapsulated and unencapsulated probiotic strains have exhibited statistically significant decrease in paw thickness. Percentage of inhibition in paw thickness of microencapsulated probiotic bacteria (Group VIII), unencapsulated strains (Group IX) were revealed 85 ± 13% and 77 ± 25%, respectively. In Hematoxylin and Eosin staining, results were revealed that the probiotic strains were exhibited anti-inflammatory effects on inflammation-induced paw tissues. qRT-PCR studies revealed upregulation of anti-inflammatory cytokine genes and down-regulation pro-inflammatory cytokine genes in probiotic-treated rat paw tissues. Further, the expression of anti-inflammatory and pro-inflammatory cytokines were examined using immunohistochemistry and ELISA methods. The probiotic administered rat paw tissue in different groups have exhibited the low level of lipid peroxides formation and higher anti-oxidant activities when compared to the control and inflammation control tissues.

Probiotics in the Treatment of Colorectal Cancer

The human microbiome plays many roles in inflammation, drug metabolism, and even the development of cancer that we are only beginning to understand. Colorectal cancer has been a focus for study in this field as its pathogenesis and its response to treatment have both been linked to the functioning of microbiota. This literature review evaluates the animal and human studies that have explored this relationship. By manipulating the microbiome with interventions such as probiotic administration, we may be able to reduce colorectal cancer risk and improve the safety and effectiveness of cancer therapy even though additional clinical research is still necessary.

Secretion metabolites of probiotic yeast, Pichia kudriavzevii AS-12, induces apoptosis pathways in human colorectal cancer cell lines

There is a common agreement on the important role of the gastrointestinal microbiota in the etiology of cancer. Benign probiotic yeast strains are able to ameliorate intestinal microbiota and regulate the host metabolism, physiology, and immune system through anti-inflammatory, antiproliferative, and anticancer effects. We hypothesized that Pichia kudriavzevii AS-12 secretion metabolites possess anticancer activity on human colorectal cancer cells (HT-29, Caco-2) via inhibiting growth and inducing apoptosis. This study aimed to assess the anticancer effect of P. kudriavzevii AS-12 secretion metabolites and the underlying mechanisms. The cytotoxicity evaluations were performed via 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay; 4',6-diamidino-2-phenylindole staining; and FACS-flow cytometry tests. Also, the effects of P. kudriavzevii AS-12 secretion metabolites on the expression level of 6 important genes (BAD, Bcl-2, Caspase-3, Caspase-8, Caspase-9 and Fas-R) involved in the extrinsic and intrinsic apoptosis pathways were studied by real-time polymerase chain reaction method. P. kudriavzevii AS-12 secretion metabolites showed significant (P < .0001) cytotoxic effects on HT-29 cells (57.5%) and Caco-2 (32.5%) compared to KDR/293 normal cells (25%). Moreover, the cytotoxic effects of examined yeast supernatant on HT-29 cells were comparable with 5-fluorouracil, as a positive control (57.5% versus 62.2% respectively). Flow cytometric results showed that the induction of apoptosis is the main mechanism of the anticancer effects. Also, according to the reverse transcriptase polymerase chain reaction results, the expression level of proapoptotic genes (BAD, Caspase-3, Caspase-8, Caspase-9, and Fas-R) in treated HT-29 and Caco-2 cells was higher than untreated and normal cells, whereas the antiapoptotic gene (Bcl-2) was downregulated. P. kudriavzevii AS-12 secretion metabolites exert its anticancer effects by inhibiting cell proliferation and inducing intrinsic and extrinsic apoptosis in colon cancer cells.

Lactobacilli enhance reactive oxygen species-dependent apoptosis-inducing signaling

H₂O₂-producing lactobacilli in the vaginal fluid have been suggested to play a potential tumor-preventive role in addition to the control of undesirable microorganisms. As the vaginal fluid also contains a significant concentration of peroxidase that might utilize lactobacilli-derived H₂O₂ as substrate for HOCl synthesis, a dominant biological role of HOCl in both natural defence systems has been postulated.

Our study shows that lactobacillus-derived H₂O₂ per se is not likely to be beneficial for the vaginal epithelium, as it causes apoptosis nonselectively in nontransformed as well as transformed cells. However, the combination of lactobacilli and peroxidase, i.e. the situation that is actually found in vivo, leads to the conversion of H₂O₂ to HOCl which does not affect non-malignant cells, as these do not generate extracellular superoxide anions. In contrast, malignant cells, due to their abundant extracellular superoxide anion generation allow the generation of apoptosis-inducing hydroxyl radicals through HOCl/superoxide anion interaction. In total, our data show that the combination of H₂O₂ -generating lactobacilli and peroxidase causes the selective elimination of malignant cells and thus might contribute to the tumorpreventive potential of lactobacilli. These findings are in good agreement with epidemiological data. The contribution of lactobacilli in this system can be completely mimicked by H₂O₂-generating glucose oxidase, indicating that it is fully explained by bacterial generation of H₂O₂.

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Lactobacillus-derived H₂O₂ induces apoptosis in nontransformed and transformed cells.

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MPO converts H₂O₂ into HOCl that exerts a selective apoptosis-inducing effect on malignant cells.

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Extracellular superoxide anions of malignant cells are crucial for selective apoptosis induction.

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A model for the tumor protective role of lactobacilli in the presence of peroxidase is presented.

Searching for the Perfect Homeostasis: Five Strains of Bifidobacterium longum From Centenarians Have a Similar Behavior in the Production of Cytokines

GOALS

To investigate the modulation of human cytokines by Bifidobacterium longum strains isolated from Centenarians. In particular, we measured the production of interleukin (IL)-12p70, interferon-γ, IL-17A, and IL-4 from human peripheral blood mononuclear cells after stimulation with live bacteria.

BACKGROUND

Probiotics may inhibit pathogens and modulate the immune system, bringing a beneficial effect on human health. Among the probiotic strains, bifidobacteria play a key role in the maturation of the host's immune system. At present, only a few comparative data are available on the effects of bifidobacteria associations on cytokine production.

STUDY

Peripheral blood mononuclear cells were isolated, cultured, and stimulated (ratio 1:1) with B. longum DLBL07, B. longum DLBL08, B. longum DLBL09, B. longum DLBL10, or B. longum DLBL11, either alone or in association. Cytokine production was determined by an enzyme-linked immunosorbent assay.

RESULTS

Both the B. longum DLBL mixture and the individual B. longum DLBL strains induced similar levels of IL-4, interferon-γ, and IL-17A. Under all conditions tested, no IL-12p70 release was detected.

CONCLUSIONS

The fact that B. longum strains were obtained from Centenarians suggests a perfect homeostasis between this specific species and the host. Moreover all the B. longum strains from Centenarians used in our study share some biological similarities.

Lactobacillus casei BL23 regulates Treg and Th17 T-cell populations and reduces DMH-associated colorectal cancer

BACKGROUND

Chronic intestinal inflammation alters host physiology and could lead to colorectal cancer (CRC). We have previously reported beneficial effects of the probiotic strain of Lactobacillus casei BL23 in different murine models of intestinal inflammation. In addition, there is an emerging interest on the potential beneficial effects of probiotics to treat CRC. We thus explored whether L. casei BL23 displays protective effects on CRC.

METHODS

Mice were subcutaneously injected with 1,2-dimethylhydrazine (DMH) weekly during 10 weeks and orally administered with L. casei BL23 in the drinking water until the 10th week. Multiple plaque lesions in the large intestine were observed macroscopically and counted and intestinal tissues were also histologically analyzed. Finally, T-cell populations and cytokine production were evaluated after co-incubation of L. casei BL23 with spleen cells from non-treated mice to determine the immuno-modulatory effects of this bacterium.

RESULTS

Our results show that oral treatment with this probiotic bacterium modulates host immune responses and significantly protect mice against DMH-induced CRC. This protection may be associated with the modulation of regulatory T-cells towards a Th17-biased immune response accompanied by the expression of regulatory cytokines (IL-6, IL-17, IL-10 and TGF-β), as demonstrated in L. casei BL23-treated splenocytes, but also with the colonic expression of IL-22 observed in vivo on L. casei BL23-treated mice; suggesting the induction of a fine-tune Th17-biased response.

CONCLUSIONS

Altogether our results reveal the high potential of L. casei BL23 to treat CRC and opens new frontiers for the study of immunomodulatory functions of probiotics.

The Potential Role of Probiotics in Cancer Prevention and Treatment

The human gut microbiota has a significant effect on many aspects of human physiology such as metabolism, nutrient absorption, and immune function. Imbalance of the microbiota has been implicated in many disorders including inflammatory bowel disease, obesity, asthma, psychiatric illnesses, and cancers. As a kind of functional foods, probiotics have been shown to play a protective role against cancer development in animal models. Clinical application of probiotics indicated that some probiotic strains could diminish the incidence of postoperative inflammation in cancer patients. Chemotherapy or radiotherapy-related diarrhea was relieved in patients who were administered oral probiotics. The present review summarizes the up-to-date studies on probiotic effects and the underlying mechanisms related to cancer. At present, it is commonly accepted that most commercial probiotic products are generally safe and can improve the health of the host. By modulating intestinal microbiota and immune response, some strains of probiotics can be used as an adjuvant for cancer prevention or/and treatment.

Probiotic and cultural characteristic of strain Lactobacillus gasseri 4/13 of human origin

Lactobacillus gasseri within the Lactobacillus acidophilus group is a major species in the human microflora. The potential probiotic properties of a L. gasseri strain of human origin were evaluated. Out of 17 studied L. gasseri strains, L. gasseri 4/13 showed the highest immunomodulatory effect (induction of interferon gamma measured by sandwich enzyme-linked immunosorbent assay) in Balb/c mouse splenocytes in vitro and the highest rate of adhesion to Caco-2 human epithelial cells. The strain also reduced the concentration of cholesterol in the growth medium by 65% as compared with the initial concentration (measured spectrophotometrically). These probiotic properties indicate that L. gasseri 4/13 could prove an attractive concentrated adjunct monoculture in the production of new functional foods. To obtain a freeze-dried bacterial concentrate from L. gasseri 4/13, the influence of different culture media, temperatures and pH values on the accumulation of cell biomass was studied. Yoghurt samples were produced using a classical fermentation technology. Freeze-dried concentrated monoculture of L. gasseri 4/13 with over 1 × 10¹⁰ CFU/g viable cells was added as an adjunct culture together with a starter. The viable L. gasseri 4/13 cells remained above the critical value of 10⁶ CFU/g during storage at 5 °C for the entire 20-day period. Organoleptic tests did not reveal any adverse change in the product taste and aroma of yoghurt samples at the 20th day. In conclusion, L. gasseri 4/13 was selected as having suitable probiotic and cultural characteristics for production of fermented milk products with high nutritional and biological value.

Multiple effects of Escherichia coli Nissle 1917 on growth, biofilm formation, and inflammation cytokines profile of Clostridium perfringens type A strain CP4

Clostridium perfringens is an important Gram-positive pathogen responsible for food poisoning, necrotic enteritis, gas gangrene, and even death. Escherichia coli Nissle 1917 (EcN) is a well-characterized probiotic strain with demonstrated benefits. In this study, we evaluated the effects of EcN on growth, toxin production, biofilm formation, and inflammatory cytokine responses of C. perfringens. In vitro co-culture experiments demonstrated that EcN inhibited growth, gas production, and toxin production (α-toxin and NetB) of C. perfringens in a dose-dependent manner. The growth inhibition effect was not observed when C. perfringens was incubated with EcN cell-free supernatants (CFSE), suggesting that growth inhibition was caused by nutrition competition during co-incubation. In vitro studies demonstrated that pre-incubation with EcN did not inhibit C. perfringens attachment to Caco-2 cells, but did reduce C. perfringens total number, toxin production, and cytotoxicity after 24 h. The similar growth inhibition results were also observed during the formation of C. perfringens biofilm. Finally, pre-incubation of EcN with RAW264.7 cells significantly decreased the production of inflammatory cytokines caused by the introduction of C. perfringens. Our results indicate that EcN can inhibit many of the pathological effects of C. perfringens in vitro conditions.

Prebiotics to fight diseases: reality or fiction?

Bacteria living in the gastrointestinal tract are crucial for human health and disease occurrence. Increasing the beneficial intestinal microflora by consumption of prebiotics, which are 'functional foods', could be an elegant way to limit the number and incidence of disorders and to recover from dysbiosis or antibiotic treatments. This review focuses on the short-chain low-digestible carbohydrates (LDCs) which are metabolized by gut microbiota serving as energy source, immune system enhancers or facilitators of mineral uptake. Intake of foods containing LDCs can improve the state of health and may prevent diseases as for example certain forms of cancer. Given the large number of different molecules belonging to LDCs, we focused our attention on fructans (inulin, fructo-oligosaccharides), galacto-oligosaccharides and resistant starches and their therapeutic and protective applications. Evidence is accumulating that LDCs can inhibit bacterial and viral infections by modulating host defense responses and by changing the interactions between pathogenic and beneficial bacteria. Animal studies and studies on small groups of human subjects suggest that LDCs might help to counteract colorectal cancer, diabetes and metabolic syndrome. The action mechanisms of LDCs in the human body might be broader than originally thought, perhaps also including reactive oxygen species scavenging and signaling events.

Delayed accumulation of intestinal coliform bacteria enhances life span and stress resistance in Caenorhabditis elegans fed respiratory deficient E. coli

Background

Studies with the nematode model Caenorhabditis elegans have identified conserved biochemical pathways that act to modulate life span. Life span can also be influenced by the composition of the intestinal microbiome, and C. elegans life span can be dramatically influenced by its diet of Escherichia coli. Although C. elegans is typically fed the standard OP50 strain of E. coli, nematodes fed E. coli strains rendered respiratory deficient, either due to a lack coenzyme Q or the absence of ATP synthase, show significant life span extension. Here we explore the mechanisms accounting for the enhanced nematode life span in response to these diets.

Results

The intestinal load of E. coli was monitored by determination of worm-associated colony forming units (cfu/worm or coliform counts) as a function of age. The presence of GFP-expressing E. coli in the worm intestine was also monitored by fluorescence microscopy. Worms fed the standard OP50 E. coli strain have high cfu and GFP-labeled bacteria in their guts at the L4 larval stage, and show saturated coliform counts by day five of adulthood. In contrast, nematodes fed diets of respiratory deficient E. coli lacking coenzyme Q lived significantly longer and failed to accumulate bacteria within the lumen at early ages. Animals fed bacteria deficient in complex V showed intermediate coliform numbers and were not quite as long-lived. The results indicate that respiratory deficient Q-less E. coli are effectively degraded in the early adult worm, either at the pharynx or within the intestine, and do not accumulate in the intestinal tract until day ten of adulthood.

Conclusions

The findings of this study suggest that the nematodes fed the respiratory deficient E. coli diet live longer because the delay in bacterial colonization of the gut subjects the worms to less stress compared to worms fed the OP50 E. coli diet. This work suggests that bacterial respiration can act as a virulence factor, influencing the ability of bacteria to colonize and subsequently harm the animal host. Respiratory deficient bacteria may pose a useful model for probing probiotic relationships within the gut microbiome in higher organisms.

Dietary modulation of the human colonic microbiota: updating the concept of prebiotics

Prebiotics are non-digestible (by the host) food ingredients that have a beneficial effect through their selective metabolism in the intestinal tract. Key to this is the specificity of microbial changes. The present paper reviews the concept in terms of three criteria: (a) resistance to gastric acidity, hydrolysis by mammalian enzymes and gastrointestinal absorption; (b) fermentation by intestinal microflora; (c) selective stimulation of the growth and/or activity of intestinal bacteria associated with health and wellbeing. The conclusion is that prebiotics that currently fulfil these three criteria are fructo-oligosaccharides, galacto-oligosaccharides and lactulose, although promise does exist with several other dietary carbohydrates. Given the range of food vehicles that may be fortified by prebiotics, their ability to confer positive microflora changes and the health aspects that may accrue, it is important that robust technologies to assay functionality are used. This would include a molecular-based approach to determine flora changes. The future use of prebiotics may allow species-level changes in the microbiota, an extrapolation into genera other than the bifidobacteria and lactobacilli, and allow preferential use in disease-prone areas of the body.

Probiotics prevent growth deficit of colon wall strata of malnourished rats post-lactation

The objective of this study was to analyze morphometrically the colon wall strata of malnourished rats supplemented with probiotics. Sixteen recently weaned Wistar rats (Rattus norvegicus) were distributed into four groups: animals that received commercial chow (G1, n = 4); animals that received the same feed as G1 and were supplemented with probiotics (G2, n = 4); animals that received chow with 4% of proteins (G3, n = 4); animals that received the same feed as G3 and were supplemented with probiotics (G4, n = 4). After 12 weeks, the proximal colon was collected and submitted to histological processing. Three-µm cuts were stained with H.E., Periodic Acid Schifff (P.A.S.) + diasthasis solution and Alcian Blue (A.B.) pH 2.5 and pH 1.0. The morphometric analysis of the intestinal wall showed that the supplementation with ABT-4 probiotic culture prevents the growth deficit of colon wall strata that normally occurs in malnourished rats right after lactation. Besides, no alteration was observed in the proportion of the number of globet cells in relation to the number of enterocytes in malnourished rats, regardless of the supplementation with probiotics.

Selenium-enriched probiotics improves murine male fertility compromised by high fat diet

A total of 75 male mice were allotted to five groups of 15 each in a completely randomized experimental design to study the effects of probiotics, inorganic selenium, and selenium-enriched probiotics on male fertility in hyperlipidemic status. The mice in group 1 were fed a normal basal diet and served as negative control. The mice in group 2 were fed a high fat diet and served as positive control. The mice in groups 3, 4, and 5 were fed the high fat diet supplemented with probiotics, inorganic selenium, and selenium-enriched probiotics, respectively. The high fat diet was composed of 15% lard, 1% cholesterol, 0.3% cholic acid, and 83.7% basal diet. Over 90% of the selenium in the selenium-enriched probiotics was present in forms of organic selenium. After the mice were fed these diets for 75 days, serumal total cholesterol, triglycerides, low density lipoprotein, high density lipoprotein, and testosterone levels, plus sperm index (count, motility and abnormalities), penis length, and weight and histopathology of testes were measured. The results showed that in the mice fed the high fat diet were significant (P < 0.01) elevations of serumal total cholesterol, triglycerides and low density lipoprotein, and decreases of high density lipoprotein. The high fat diet caused a decline in serumal testosterone level, reduced semen quality, and atrophy and degeneration of seminiferous tubules. No effects on penis length or relative weight of testis were observed. Supplementation of probiotics, inorganic selenium, or selenium-enriched probiotics to the high fat diet significantly alleviated (P < 0.05) the adverse effects of hyperlipidemia by reducing testicular tissue injury, increasing serumal testosterone level, and improving sperm indexes. It was concluded that hyperlipidemia had significant adverse effects on male fertility, which could be ameliorated at various degrees by feeding the diets supplemented with probiotics, inorganic selenium, or selenium-enriched probiotics. Selenium-enriched probiotics or inorganic selenium supplementation gave better results than probiotics supplementation and may be used to improve animal and human male fertility compromised by hyperlipidemia or obesity.

Synergistic impact of Lactobacillus fermentum, Lactobacillus plantarum and vincristine on 1,2-dimethylhydrazine-induced colorectal carcinogenesis in mice

Lactobacillus sp. is the most dominant probiotic strain of bacteria. Evidence indicates that the consumption of Lactobacillus sp. reduces the risk of colorectal cancer in animal models. The present study was carried out to determine whether administration of Lactobacillus fermentum/ Lactobacillus plantarum alone or in combination with vincristine have a synergistic impact on the control of colorectal cancer in an animal model. Mice with 1,2 dimethylhydrazine (DMH) hydrochloride-induced colon cancer were fed with L. fermentum and L. plantarum isolated along with vincristine. An increase in body weight, a decrease in ammonia concentration, a decrease in β glucosidase and β glucuronidase enzyme activity and a reduction in the number of crypts in the mice in the pre-carcinogen-induced group was noted when compared to these variables in the post-carcinogen-induced group. The body weight of the mice fed L. fermentum along with vincristine was increased (6.5 g), and was found to be 3.5 times higher compared to that of the control. A marked decrease in the ammonia concentration (240 mg), and β glucosidase (0.0023 IU) and β glucopyranose enzyme activity (0.0027 IU) was observed; 22.59% less ammonia concentration, 73.26% less β glucosidase activity and 56.46% less β glucuronidase enzyme activity was noted when compared to the control. A significant reduction in the number of aberrant crypt foci (ACF) (90%) was observed when compared to the control. Maximum protection was observed in the mice fed the probiotics and vincristine prior to cancer induction. Among the different dietary combinations tested in the present study, L. fermentum and vincristine showed a more extensive reduction in ammonia concentration, β glucosidase, β glucuronidase activity and the number of ACF.

Techniques used to characterize the gut microbiota: a guide for the clinician

The gut microbiota is a complex ecosystem that has a symbiotic relationship with its host. An association between the gut microbiota and disease was first postulated in the early 20(th) century. However, until the 1990s, knowledge of the gut microbiota was limited because bacteriological culture was the only technique available to characterize its composition. Only a fraction (estimated at <30%) of the gut microbiota has been cultured to date. Since the 1990s, advances in culture-independent techniques have spearheaded our knowledge of the complexity of this ecosystem. These techniques have elucidated the microbial diversity of the gut microbiota and have shown that alterations in the gut microbiota composition and function are associated with certain disease states, such as IBD and obesity. These new techniques are fast, facilitate high throughput, identify organisms that are uncultured to date and enable enumeration of organisms present in the gut microbiota. This Review discusses the techniques that can used to characterize the gut microbiota, when they can be applied to human studies and their relative advantages and limitations.

Probiotics prevent the development of 1,2-dimethylhydrazine (DMH)-induced colonic tumorigenesis through suppressed colonic mucosa cellular proliferation and increased stimulation of macrophages

Probiotics modulate immunity and inhibit colon carcinogenesis in experimental models, but these effects largely depend on the bacterial strain, and the precise mechanisms are not well understood. Therefore, we studied the effect of Bifidobacterium longum and/or Lactobacillus gasseri on the development of 1,2-dimethylhydrazine (DMH)-induced colonic precancerous lesions and tumors in mice while delineating the possible mechanisms involved. The results suggest that dietary consumption of probiotics (B. longum and L. gasseri) resulted in a significant inhibition of DMH-induced aberrant crypt foci (ACF) formation in male ICR mice. Long-term (24 weeks) dietary consumption of probiotics resulted in a reduction of colon tumor multiplicity and the size of the tumors. Administration of B. longum and L. gasseri suppressed the rate of colonic mucosa cellular proliferation in a manner correlating with the inhibition of tumor induction by DMH. In addition, the phagocytic activity of peritoneal macrophages was significantly increased in the DMH-treated mice that were fed various doses of B. longum, but not with L. gasseri or combined probiotics (B. longum + L. gasseri). We also found that L. gasseri significantly increased the proliferation of RAW264.7 macrophage cells through an increase in S phase DNA synthesis, which was related to the up-regulation of proliferating cell nuclear antigen (PCNA) and cyclin A. Taken together, these results demonstrate the in vivo chemopreventive efficacy and the immune stimulating mechanisms of dietary probiotics against DMH-induced colonic tumorigenesis.

[Chemopreventive effects of 5-fluorouracil and lactoferrin on goldfish intestinal carcinogenesis induced by 1,2-dimethylhydrazine]

The present study was carried out to examine the chemopreventive effects of 5-fluorouracil (5-FU) and lactoferrin (LF) on goldfish intestinal carcinogenesis induced by 1,2-dimethylhydrazine (DMH). DMH was given to fish by intraperitoneal injection in a dosage of 15 mg/kg body weight once a week for 6 weeks. Eight weeks after the initial DMH injection, fish were randomly divided into 2 groups, control and LF-treated groups. Control fish fed a commercial diet. LF- treated fish fed a commercial diet with bovine lactoferrin (oral administration at 200 mg/kg body weight/day). Ten weeks after the initial DMH injection, each was divided into 2 groups, saline- and 5-FU- treated groups. Physiological saline for freshwater fish (0.75% NaCl solution) in the saline-treated fish and 5-FU dissolved in 0.75% NaCl solution in the 5-FU-treated (75 mg/kg body weight) fish were injected intramuscularly three times every other day, respectively. The mean number of precancer cell foci (PCF) per intestine was 2.7 in DMH treated fish. PCF showed broader distribution in the entire intestine derived from DMH-treated fish. LF-only-treatment has no effect on the number of PCF. Mean number of PCF in 5-FU-only-treated fish decreased in comparison with that of the saline-treated control group, though no statistically significant reduction in PCF was found. But if 5-FU treatment was added to LF pretreatment, a statistically significant reduction in the number of PCF was observed. Pretreatment with LF for 2 weeks also reduced the deleterious side effects of 5-FU.

Fructo-oligosaccharide production from inulin through partial citric or phosphoric acid hydrolyses

Purified inulin from Dahlia tubers was partially hydrolyzed to form fructo-oligosaccharides by using citric or phosphoric acids (pH, 2.0-2.5) as mild acid catalysts. The ideal kinetic conditions to ensure a high yield of fructo-oligosaccharides relative to free fructose were a temperature range of 85°C-95°C, a hydrolysis time of 15-25 minutes, and a catalyst pH of 2.5. At the higher temperature and the longest hydrolysis time, an inversion of the product ratio occurred. Under these conditions, co-generation of hydroxymethylfurfural occurred, and it was eliminated by activated charcoal. Unlike in classic hydrolysis with hydrochloric or sulfuric acid, deionization of the actual hydrolysates was not necessary because the catalyst neutralization with common bases results in the formation of co-nutrients with alternative uses as foods or fermentation substrates. These whole hydrolysates can be advantageously added as nutraceuticals to carbonated beverages and acidic foods, such as soft drinks and yogurts.

Bacteriocinogeny in experimental pigs treated with indomethacin and Escherichia coli Nissle

AIM: To evaluate bacteriocinogeny in short-term high-dose indomethacin administration with or without probiotic Escherichia coli Nissle 1917 (EcN) in experimental pigs.

METHODS: Twenty-four pigs entered the study: Group A (controls), Group B (probiotics alone), Group C (indomethacin alone) and Group D (probiotics and indomethacin). EcN (3.5 × 10¹⁰ bacteria/d for 14 d) and/or indomethacin (15 mg/kg per day for 10 d) were administrated orally. Anal smears before and smears from the small and large intestine were taken from all animals. Bacteriocin production was determined with 6 different indicator strains; all strains were polymerase chain reaction tested for the presence of 29 individual bacteriocin-encoding determinants.

RESULTS: The general microbiota profile was rather uniform in all animals but there was a broad diversity in coliform bacteria (parallel genotypes A, B1, B2 and D found). In total, 637 bacterial strains were tested, mostly Escherichia coli (E. coli). There was a higher incidence of non-E. coli strains among samples taken from the jejunum and ileum compared to that of the colon and rectum indicating predominance of E. coli strains in the large intestine. Bacteriocinogeny was found in 24/77 (31%) before and in 155/560 (28%) isolated bacteria at the end of the study. Altogether, 13 individual bacteriocin types (out of 29 tested) were identified among investigated strains. Incidence of four E. coli genotypes was equally distributed in all groups of E. coli strains, with majority of genotype A (ranging from 81% to 88%). The following types of bacteriocins were most commonly revealed: colicins Ia/Ib (44%), microcin V (18%), colicin E1 (16%) and microcin H47 (6%). There was a difference in bacteriocinogeny between control group A (52/149, 35%) and groups with treatment at the end of the study: B: 31/122 (25%, P = 0.120); C: 43/155 (28%, P = 0.222); D: 29/134 (22%, P = 0.020). There was a significantly lower prevalence of colicin Ib, microcins H47 and V (probiotics group, P < 0.001), colicin E1 and microcin H47 (indomethacin group, P < 0.001) and microcins H47 and V (probiotics and indomethacin group, P = 0.025) compared to controls. Escherichia fergusonii (E. fergusonii) was identified in 6 animals (6/11 isolates from the rectum). One strain was non-colicinogenic, while all other strains of E. fergusonii solely produced colicin E1. All animals started and remained methanogenic despite the fact that EcN is a substantial hydrogen producer. There was an increase in breath methane (after the treatment) in 5/6 pigs from the indomethacin group (C).

CONCLUSION: EcN did not exert long-term liveability in the porcine intestine. All experimental pigs remained methanogenic. Indomethacin and EcN administered together might produce the worst impact on bacteriocinogeny.

The ability of green tea to positively modulate key markers of gastrointestinal function in rats

The beneficial effects of selenium-containing green tea (Se-GTE, 1.44 mg selenium/kg dry leaves) and China green tea (CH-GTE, 0.13 mg selenium/kg leaves) on the population size of lactobacilli and bifidobacteria and the activity of two microbial enzymes in the caeca of rats have been investigated. Oral gavage of rats with Se-GTE extract for 6 days resulted in a significant increase in caecal counts of lactobacilli and bifidobacteria (p < 0.05) while significantly reducing the caecal counts of bacteroides and clostridial bacteria. In contrast, gavaging the rats with CH-GTE extract for 6 days resulted in a slight but not significant increase in the numbers of caecal lactobacilli and bifidobacteria but decreased significantly the numbers of bacteroides (p < 0.05) and clostridia (p < 0.05). In addition, rats gavaged with CH-GTE and Se-GTE showed a 17.2% and 21.3% reduction in the activity of the bacterial enzyme β-glucuronidase, respectively, when compared with the rats gavaged with water only. β-glucuronidase is considered to be one of the enzymes that increases the risk for colorectal cancer. Moreover, gavaging rats with these teas resulted in 19% and 25.5% increments in the activity of β-glucosidase, respectively. In conclusion, Se-GTE showed both bifidogenic and lactogenic effects and the high level of selenium may be behind the superiority of this tea over CH-GTE.

Peptides from Lactobacillus hydrolysates of bovine milk caseins inhibit prolyl-peptidases of human colon cells

Prolyl-rich peptides derived from hydrolysates of bovine caseins have been previously shown to inhibit angiotensin converting enzyme (ACE) activity, suggesting that they may also be able to inhibit the enzymatic activities of prolyl-specific peptidases. This study shows that peptides derived from α(S1)-casein and β-casein inhibited the enzymatic activities of purified recombinant matrix metalloprotease (MMP)-2, MMP-7, and MMP-9. The inhibitory efficacy was sequence-dependent. These peptides also selectively inhibited the enzymatic activities of prolyl-amino-peptidases, prolyl-amino-dipeptidases, and prolyl-endopeptidases in extracts of HT-29 and SW480 human colon carcinoma cells, but not in intact cells. They were not cytotoxic or growth inhibitory for these cells. Thus, the prolyl-rich selected peptides were good and selective inhibitors of MMPs and post-proline-cleaving proteases, demonstrating their potential to control inadequate proteolytic activity in the human digestive tract, without inducing cytotoxic effects.

Coenzyme Q10 attenuated DMH-induced precancerous lesions in SD rats

Coenzyme Q10 (CoQ10) is known to be a compound with mitochondrial bioenergetic functions and antioxidant activity. In this study, we evaluated the effect of CoQ10 on the formation of aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH), DMH-induced leukocytic DNA damage and gene expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by real-time PCR in colonic mucosa of male SD rats. The animals were divided into three groups and fed a casein-based high-fat and low fiber diet (100 g lard+20 g cellulose/kg diet) with or without CoQ10 (0.4 mg in soybean oil/kg BW/d, i.p.). One week after beginning the diets, the rats were subjected to 6 wk of treatment with DMH (30 mg/kg/wk, s.c.) and CoQ10 treatments continued over the entirety of the experimental period (59 d). Administration of CoQ10 resulted in reduction of ACF numbers, to 20% of the carcinogen control value. CoQ10 supplementation induced an antigenotoxic effect on DMH-induced DNA damage in the blood cells. Colonic mucosa of DMH-injected rats had significantly greater COX-2 and iNOS gene expression than those of control rats, while treatment with CoQ10 induced an inhibitory effect on over-expression of COX-2 and iNOS in colon tumors. Our results provide evidence that CoQ10 has a protective effect on the process of colon carcinogenesis, suppressing the development of preneoplastic lesions, possibly by modulating COX-2 and iNOS gene expression in colonic mucosa and DNA damage in leukocytes, suggesting that CoQ10 has chemotherapeutic activity.

Saccharomyces boulardii inhibits EGF receptor signaling and intestinal tumor growth in Apc(min) mice

BACKGROUND & AIMS

Saccharomyces boulardii (Sb) is a probiotic yeast with anti-inflammatory and anti-microbial activities and has been used for decades in the prevention and treatment of a variety of human gastrointestinal disorders. We reported previously that Sb modulates host inflammatory responses through down-regulation of extracellular signal-regulated kinase (Erk)1/2 activities both in vitro and in vivo. The aim of this study was to identify upstream mediators responsible for extracellular signal-regulated kinase (Erk)1/2 inactivation and to examine the effects of Sb on tumor development in Apc(Min) mice.

METHODS

Signaling studies of colon cancer cells were done by western blot. Cell proliferation was measured by MTS and BrdU assay. Apoptosis was examined by flow cytometry, tunel assay and caspase assay. Apc(Min) mice were orally given Sb for 9 weeks before sacrifice for tumor analysis.

RESULTS

We found that the epidermal growth factor receptor (EGFR) was deactivated upon exposure to Sb, leading to inactivation of both the EGFR-Erk and EGFR-Akt pathways. In human colonic cancer cells, Sb prevented EGF-induced proliferation, reduced cell colony formation, and promoted apoptosis. HER-2, HER-3, and insulin-like growth factor-1 receptor were also found to be inactivated by Sb. Oral intake of Sb reduced intestinal tumor growth and dysplasia in C57BL/6J Min/+ (Apc(Min)) mice.

CONCLUSIONS

Thus, in addition to its anti-inflammatory effects, Sb inhibits EGFR and other receptor tyrosine kinase signaling and thereby may also serve a novel therapeutic or prophylactic role in intestinal neoplasia.

Probiotic bile salt hydrolase: current developments and perspectives

Probiotic has modernized the current dietetic sense with novel therapeutic and nutritional benefits to the consumers. The presence of bile salt hydrolase (BSH) in probiotics renders them more tolerant to bile salts, which also helps to reduce the blood cholesterol level of the host. This review focuses on the occurrence of bile salt hydrolase among probiotics and its characterization, importance, applications, and genetics involved with recent updates. Research on bile salt hydrolase is still in its infancy. The current perspective reveals a huge market potential of probiotics with bile salt hydrolase. Intensive research in this field is desired to resolve some of the lacunae.

Estimation of the potential antitumor activity of microencapsulated Lactobacillus acidophilus yogurt formulation in the attenuation of tumorigenesis in Apc(Min/+) mice

There is a strong correlation between orally administered probiotics and suppression of the low-grade inflammation that can lead to restoration of normal local immune functions. We studied the potential immunomodulatory and antitumorigenic properties of microencapsulated probiotic bacterial cells in a yogurt formulation in Min mice carrying a germline APC mutation. Daily oral administration of microencapsulated Lactobacillus acidophilus bacterial cells in the yogurt formulation mice resulted in significant suppression of colon tumor incidence, tumor multiplicity, and reduced tumor size. Results show that oral administration of microencapsulated L. acidophilus contributed to the stabilization of animal body weight and decreased the release of bile acids. Histopathological analyses revealed fewer adenomas in treated versus untreated animals. Furthermore, treated animals exhibited fewer gastrointestinal intra-epithelial neoplasias with a lower grade of dysplasia in detected tumors. Results suggest that oral administration of microencapsulated probiotic L. acidophilus exerts anti-tumorous activity, which consequently leads to reduced tumor outcome.

Recent advances and remaining gaps in our knowledge of associations between gut microbiota and human health

The complex gut microbial flora harbored by individuals (microbiota) has long been proposed to contribute to intestinal health as well as disease. Pre- and probiotic products aimed at improving health by modifying microbiota composition have already become widely available and acceptance of these products appears to be on the rise. However, although required for the development of effective microbiota based interventions, our basic understanding of microbiota variation on a population level and its dynamics within individuals is still rudimentary. Powerful new parallel sequence technologies combined with other efficient molecular microbiota analysis methods now allow for comprehensive analysis of microbiota composition in large human populations. Recent findings in the field strongly suggest that microbiota contributes to the development of obesity, atopic diseases, inflammatory bowel diseases and intestinal cancers. Through the ongoing National Institutes of Health Roadmap ‘Human Microbiome Project’ and similar projects in other parts of the world, a large coordinated effort is currently underway to study how microbiota can impact human health. Translating findings from these studies into effective interventions that can improve health, possibly personalized based on an individuals existing microbiota, will be the task for the next decade(s).

Effect of Lactobacillus casei DN-114001 application on the activity of fecal enzymes in children after liver transplantation

Immunosuppressive and antibacterial regimens in children after liver transplantation create a gut microflora imbalance that can be indirectly measured by the activity of fecal enzymes. The aim of this study was to specify the influence of diet supplementation with probiotic Lactobacillus casei DN on the activity of beta-glucuronidase, beta-glucosidase, and urease. Twenty-five children after liver transplantation (13 girls, 12 boys) ages 3 to 17 years were enrolled in the study. Two months after bacteria application the levels of all 3 enzymes decreased, reaching statistical significance for beta-glucuronidase and beta-glucosidase. Complete rebound in enzyme activity was observed months after the end of probiotic supplementation. We concluded that Lactobacillus casei DN-114001 consumption decreased fecal enzyme activity, a beneficial effect limited to the period of bacteria intake.

Effects of the probiotic agent Saccharomyces Boulardii on the DNA damage in acute necrotizing pancreatitis induced rats

Pancreatitis is a mild and self-limiting disease. Although severe forms such as acute necrotizing pancreatitis (ANP) are rare it is associated with significant mortality rate reported to be 30-70%. Probiotics are viable microbial dietary supplements when introduced in sufficient quantities can have beneficial effects. The physiological effects of probiotics include suppression of bacterial infections, production of some digestive enzymes and vitamins and reconstruction of normal intestinal microflora. In the present study, the aim was to investigate the role of probiotics on the DNA damage in the peripheral lymphocytes, in the exfoliated epithelial cells and lymphocytes of the peritoneal fluids and in the pancreatic acinar cells of ANP induced rats. DNA damage was determined by COMET assay. ANP was induced by intravenous infusion of cerulein and superimposed infusion glycodeoxycholic acid into biliopancreatic duct. Saccharomyces Boulardii was used as the probiotic agent. DNA damage in pancreatic acinar cells and exfoliated epithelial cells and the lymphocytes of the peritoneal fluids was significantly higher in pancreatitis group compared to the controls and probiotic treated groups (P<0.001). No significant difference was observed in the DNA damage between the groups in the peripheral lymphocytes. In conclusion; our results support that probiotic agent Saccharomyces Boulardii can diminish bacterial infections and offer health benefits in the therapy of pancreatitis.

Effects of milk fermented by Lactobacillus gasseri SBT2055 on adipocyte size in rats

Despite adequate scientific evidence of the potential benefits of probiotics to human health or disease prevention, their contribution to the growth of adipose tissue remains to be established. Four-week-old male Sprague-Dawley rats were fed a diet containing skim milk (control diet) or skim milk fermented by Lactobacillus gasseri SBT2055 (LGSP diet) for 4 weeks. Their body weight gain, adipose tissue weight, adipocyte size distribution profile, blood and hepatic lipids, and serum leptin, glucose and adiponectin levels were determined. There was a significant reduction in average adipocyte size in mesenteric white adipose tissue (P = 0.004). Moreover, the rats fed the LGSP diet displayed greater numbers of small adipocytes from mesenteric and retroperitoneal adipose tissues than did those on the control diet. Whereas adiponectin concentrations did not differ between the groups, serum leptin concentrations were decreased to 32 % in the LGSP diet group compared with the control group. Concentrations of serum glucose and lipids, and liver lipids, except for the liver TAG level, were similar in the two groups. These results indicate a possible role for a fermented milk product in the regulation of adipose tissue growth.

A probiotic strain of Bacillus polyfermenticus reduces DMH induced precancerous lesions in F344 male rat

Bacillus polyfermenticus has been used in an effective treatment for long-term intestinal disorders, as live strains in the form of active endospores have been shown to reach the target intestine successfully. In this study, we have assessed the effects of B. polyfermenticus on the antioxidant system and the process of colon carcinogenesis in male F344 rats. The rats were divided into three groups after a 1-week adaptation period, and were then fed on either a high-fat and low-fiber diet (control and DMH groups), or a high-fat and low-fiber diet supplemented with B. polyfermenticus (3.1x10(8) cfu/d) (DMH+B. polyfermenticus group). One week after beginning the diets, the rats were subjected to 6 weeks of treatment with 1,2-dimethylhydrazine (DMH, 30 mg/kg/week, s.c.). The dietary treatments continued over the entirety of the experimental period. Nine weeks after the initial DMH injection, the rats supplemented with B. polyfermenticus evidenced significantly lower numbers of aberrant crypt foci than were observed in the DMH group. Injections with DMH resulted in significantly higher leukocytic DNA damage and plasma lipid peroxidation levels, as well as a lower plasma total antioxidant potential, and these factors recovered as the result of supplementation with B. polyfermenticus. These data indicate that B. polyfermenticus exerts a protective effect on the antioxidant system and the process of colon carcinogenesis, thereby suppressing the development of preneoplastic lesions.