Do you have a probiotic in your future?

Clinical Implications of Probiotics in Oral and Periodontal Health: A Comprehensive Review

Probiotic therapy represents a novel concept in dentistry. The microbial nature of dental plaque can be altered, or the probiotic strategy can efficiently inhibit oral pathogens. Probiotics are dietary supplements that are vital for boosting immunity as they include beneficial bacteria and yeast. In dentistry and medicine, the interest in probiotics, prebiotics, and synbiotics is increasing. By forming a biofilm and assisting in preventing dental cavities, probiotics play a crucial role in dentistry and significantly impact immunity. Prebiotics are non-digestible dietary supplements that enhance health by increasing the quantity and activity of beneficial bacteria such as Lactobacilli and Bifidobacteria. It has been demonstrated that prebiotics, in addition to probiotics, can help treat oral diseases. They promote the growth and activity of beneficial organisms while inhibiting potentially harmful bacteria's growth and activity. Synbiotics are dietary supplements that combine probiotics and prebiotics, believed to work in tandem through a process known as synergism. Studies have indicated that synbiotics, or a combination of probiotics with a prebiotic, may have greater efficacy than either supplement alone.

An In Vitro Evaluation of the Antimicrobial Activity of Probiotics Against Endodontic Pathogens

Background and aim: Despite scientific evidence that even some microorganisms may be useful, endodontic intervention has persisted to prioritize the removal of all microorganisms from the root canal system. Indeed, information regarding the significant role of probiotic microorganisms in endodontic treatment has been sparse. This study aimed to carry out an in vitro evaluation of the antimicrobial activity of probiotics against endodontic pathogens.

Methods: The evaluation was carried out in three stages. In Stage 1, the agar cup well procedure was used to analyse the efficiency of probiotics microorganisms against Enterococcus faecalis bacteria and Candida albicans microorganisms in the planktonic stage. In Stage 2, a deferred antagonistic experiment was used to determine the activity of probiotic microorganisms against endodontic pathogens like E. faecalis and C. albicans in the planktonic phase. In Stage 3, biofilm phase evaluation of an intracanal probiotic microorganism carrier was done. The region of maximum inhibition was measured at the end of Stages 1 and 2. The antimicrobial activity was recognized when the dimension of the region of maximum inhibition was 10 mm or above. The colony-forming unit/millilitre was measured at the end of Stage 3.

Results: There was marked antimicrobial activity of probiotic microorganisms against the pathogenic microorganisms E. faecalis as well as C. albicans in Stages 1 and 3, i.e., during the evaluation involving agar cup and evaluation at the biofilm stage. However, no antimicrobial activity of probiotic microorganisms was observed against pathogenic endodontic microorganisms in Stage 2, i.e., during evaluation involving the use of the deferred antagonistic technique.

Conclusion: It can be concluded that probiotic therapy is a promising antibacterial treatment approach that should be further investigated. This study shows that probiotics can help effectively in endodontic treatment and that more in vitro as well as in vivo research is needed to fully appreciate the advantages of bacteriotherapy in the field of endodontics.

Effects of Vitamin B2 Supplementation in Broilers Microbiota and Metabolome

The study of the microbiome in broiler chickens holds great promise for the development of strategies for health maintenance and performance improvement. Nutritional strategies aimed at modulating the microbiota-host relationship can improve chickens' immunological status and metabolic fitness. Here, we present the results of a pilot trial aimed at analyzing the effects of a nutritional strategy involving vitamin B2 supplementation on the ileum, caeca and litter microbiota of Ross 308 broilers, as well as on the metabolic profile of the caecal content. Three groups of chickens were administered control diets and diets supplemented with two different dosages of vitamin B2. Ileum, caeca, and litter samples were obtained from subgroups of birds at three time points along the productive cycle. Sequencing of the 16S rRNA V3-V4 region and NMR metabolomics were used to explore microbiota composition and the concentration of metabolites of interest, including short-chain fatty acids. Vitamin B2 supplementation significantly modulated caeca microbiota, with the highest dosage being more effective in increasing the abundance of health-promoting bacterial groups, including Bifidobacterium, resulting in boosted production of butyrate, a well-known health-promoting metabolite, in the caeca environment.

Application of Bacillus coagulans in Animal Husbandry and Its Underlying Mechanisms

Simple Summary

Probiotics, a kind of feed additive, are widely used in animal husbandry and the effects are quite positive. Many strains of Bacillus spp. are currently used as probiotic dietary supplements in animal feeds. Bacillus coagulans, a probiotic with good application prospects, piqued our strong interest. In this review, information on Bacillus coagulans in scientific research and production practices is summarized.

Abstract

In recent decades, probiotics have attracted widespread attention and their application in healthcare and animal husbandry has been promising. Among many probiotics, Bacillus coagulans (B. coagulans) has become a key player in the field of probiotics in recent years. It has been demonstrated to be involved in regulating the balance of the intestinal microbiota, promoting metabolism and utilization of nutrients, improving immunity, and more importantly, it also has good industrial properties such as high temperature resistance, acid resistance, bile resistance, and the like. This review highlights the effects of B. coagulans in animal husbandry and its underlying mechanisms.

Antimicrobial activity of probiotics against endodontic pathogens:- A preliminary study

Introduction

The purpose of this study was to evaluate the antibacterial effectiveness of probiotics lactobacilli group and Bifidobacterium against Enterococcus faecalis and Candida albicans in both planktonic stage and biofilm stage.

Materials and Methods

Phase 1 of the study was conducted by agar well diffusion method. About 0.5 ml of test pathogen culture was inoculated on 20 ml of molten agar and allowed to solidify. 4-5 circular wells of diameter 8-10 mm were punched in each poured plates and 150 μl of diluted test samples were added to the wells. Phase 2 was deferred antagonism test, wherein purified culture of pathogen strain was streaked at right angle to the original producer growth and incubated at 37°C for 24 h. Zone of inhibition was measured for both the phases. Phase 3 biofilm stage evaluation was conducted by mixing 9 ml of 30% poloxamer 407 and De Man, Rogosa and Sharpe (MRS) broth in a test tube with 500 μl of either pathogen, together with 500 μl of test probiotic strains and incubated (37°C, 48 h), followed by serially diluting the mixture by 1 ml into 9 ml sterile saline till 10⁸ dilutions for evaluation of colony-forming unit/ml counts. Controls were endodontic pathogens in 30% poloxamer with MRS broth and no probiotics.

Results

Results were evaluated and statistically analysed using one-way analysis of variance and unpaired t-test. In the planktonic stage, probiotics showed inhibitory activity against endodontic pathogens with valid statistical significance (P < 0.05), while there was no activity by deferred antagonism method. In biofilm stage, all three probiotics showed growth reduction for E. faecalis, while lactobacilli group showed reduction in C. albicans colonies.

Conclusion

This preliminary study suggested that probiotics are effective for preventing the growth of endodontic pathogens in vitro. Poloxamer could be utilised as an ideal delivery vehicle for probiotics.

[Association of food patterns with different forms of small intestinal bacterial overgroth syndrome and treatment efficacy]

AIM

To assess food patterns in patients with different types of SIBO and their impact onto the course and treatment outcomes.

MATERIALS AND METHODS

The data of 988 patients who signed informed consent surved as a source data. On the basis of lactulose breath test (LBT; GastroCH4eck, Bedfont, UK), the patients were selected into one of the studied groups: SIBO-H2, SIBO-CH4, SIBO-CH4-H2 and control. Twenty - four hours food recall test was used to analyze nutritional habits. In patients with SIBO-H2, standard treatment with Tilichinol 100 mg/Tilbrochinol 200 mg (Intetrix, Beaufour-Ipsen International, France) 2 caps BID for 10 days) was provided. Efficacy of treatment was assessed on the bass of the result of LBT 2 month after treatment completion. Mann-Whitney T test (Statistica 10, StatSoft, USA) was used to compare nutritional patterns in patients with or without SIBO, in different types of SIBO and in accordance to the results of treatment.

RESULTS AND DISCUSSION

Nine hundred eighty eight patients were enrolled. On the basis of hydrogene breath test they were divided into 4 main groups: SIBO of hydrogen - producing flora (SIBO-H2, n=526), methane - producing flora (SIBO-CH4, n=129), SIBO with hyperproduction of methane and hydrogene (SIBO-CH4-H2, n=225). The control group consisted of 108 patients with no no excessive gas production on LBT. In contrast to controls, nutritional patterns of patients with SIBO were characterized by low dietary fiber and amount of red meat dishes in the rations. Those with SIBO-CH4 consumed more fruits (p=0.03), vegetables (p=0.003), and fish (p=0.026), compared to those with other variants of SIBO and the control group. Nutritional patterns of SIBO-H2 group were characterized by larger amount of poultry meat consumption (p=0.026) compared to other SIBO groups and controls. In SIBO-H2 "cured" group greater amounts of buckwheat (p.

Isolation and Identification of Lactic Acid Bacteria Probiotic Culture Candidates for the Treatment of Salmonella enterica Serovar Enteritidis in Neonatal Turkey Poults

The effect of Lactobacillus spp.-based probiotic candidates on Salmonella enterica serovar Enteritidis (SE) colonization was evaluated in two separate experiments. In each experiment, sixty-one day-of-hatch female turkey poults were obtained from a local hatchery. In both experiments, poults were challenged via oral gavage with 10⁴ cfu/poult of SE and randomly allocated to one of two groups (n = 30 poults): (1) the positive control group and (2) the probiotic treated group. Heated brooder batteries were used for housing each group separately and poults were allowed ad libitum access to water and unmedicated turkey starter feed. 1 h following the SE challenge, poults were treated with 10⁶ cfu/poult of probiotic culture via oral gavage or phosphate-buffered saline （PBS）to control groups. A total of 24 h post-treatment, poults were euthanized and the ceca and cecal tonsils from twenty poults were collected aseptically for SE recovery. In both trials, a significant reduction in the incidence and log₁₀ cfu/g of SE were observed in poults treated with the probiotic when compared with control poults (p ≤ 0.05). The results of the present study suggest that the administration of this lactic acid-producing bacteria (LAB)-based probiotic 1 h after an SE challenge can be useful in reducing the cecal colonization of this pathogen in neonatal poults.

Bacteriocin production and adhesion properties as mechanisms for the anti-listerial activity of Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA

Probiotics play an important role in maintaining a healthy and stable intestinal microbiota, primarily by preventing infection. Probiotic lactic acid bacteria (LAB) are known to be inhibitory to many bacterial enteric pathogens, including antibiotic-resistant strains. Whilst the positive role that probiotics have on human physiology, specifically in the treatment or prevention of specific infectious diseases of the gastro-intestinal tract (GIT) is known, the precise mechanistic basis of these effects remains a major research goal. In this study, molecular evidence to underpin the protective and anti-listerial effect of Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA against orally administered Listeria monocytogenes EGDe in the GIT of mice is provided. Bacteriocins plantaricin 423 and mundticin ST4SA, produced by L. plantarum 423 and E. mundtii ST4SA, respectively, inhibited the growth of L. monocytogenes in vitro and in vivo. Bacteriocin-negative mutants of L. plantarum 423 and E. mundtii ST4SA failed to exclude L. monocytogenes EGDe from the gastrointestinal tract (GIT) of mice. Furthermore, L. plantarum 423 and E. mundtii ST4SA failed to inhibit recombinant strains of L. monocytogenes EGDe in vivo that expressed the immunity proteins of the two bacteriocins. These results confirmed that bacteriocins plantaricin 423 and mundticin ST4SA acted as anti-infective mediators in vivo. Compared to wild type strains, mutants of L. plantarum 423 and E. mundtii ST4SA, in which the adhesion genes were knocked out, were less effective in the exclusion of L. monocytogenes EGDe from the GIT of mice. This work demonstrates the importance of bacteriocin and adhesion genes as probiotic anti-infective mechanisms.

Human microbiota, blood group antigens, and disease

Far from being just "bugs in our guts," the microbiota interacts with the body in previously unimagined ways. Research into the genome and the microbiome has revealed that the human body and the microbiota have a long-established but only recently recognized symbiotic relationship; homeostatic balance between them regulates body function. That balance is fragile, easily disturbed, and plays a fundamental role in human health-our very survival depends on the healthy functioning of these microorganisms. Increasing rates of cardiovascular, autoimmune, and inflammatory diseases, as well as epidemics in obesity and diabetes in recent decades are believed to be explained, in part, by unintended effects on the microbiota from vaccinations, poor diets, environmental chemicals, indiscriminate antibiotic use, and "germophobia." Discovery and exploration of the brain-gut-microbiota axis have provided new insights into functional diseases of the gut, autoimmune and stress-related disorders, and the role of probiotics in treating certain affective disorders; it may even explain some aspects of autism. Research into dietary effects on the human gut microbiota led to its classification into three proposed enterotypes, but also revealed the surprising role of blood group antigens in shaping those populations. Blood group antigens have previously been associated with disease risks; their subsequent association with the microbiota may reveal mechanisms that lead to development of nutritional interventions and improved treatment modalities. Further exploration of associations between specific enteric microbes and specific metabolites will foster new dietary interventions, treatment modalities, and genetic therapies, and inevitably, their application in personalized healthcare strategies. This article is categorized under: Laboratory Methods and Technologies > Metabolomics Translational, Genomic, and Systems Medicine > Translational Medicine Physiology > Mammalian Physiology in Health and Disease.

Western Indian Rural Gut Microbial Diversity in Extreme Prakriti Endo-Phenotypes Reveals Signature Microbes

Heterogeneity amidst healthy individuals at genomic level is being widely acknowledged. This, in turn, is modulated by differential response to environmental cues and treatment regimens, necessitating the need for stratified/personalized therapy. We intend to understand the molecular determinants of Ayurvedic way (ancient Indian system of medicine) of endo-phenotyping individuals into distinct constitution types termed “Prakriti,” which forms the basis of personalized treatment. In this study, we explored and analyzed the healthy human gut microbiome structure within three predominant Prakriti groups from a genetically homogenous cohort to discover differentially abundant taxa, using 16S rRNA gene based microbial community profiling. We found Bacteroidetes and Firmicutes as major gut microbial components in varying composition, albeit with similar trend across Prakriti. Multiple species of the core microbiome showed differential abundance within Prakriti types, with gender specific signature taxons. Our study reveals that despite overall uniform composition of gut microbial community, healthy individuals belonging to different Prakriti groups have enrichment of specific bacteria. It highlights the importance of Prakriti based endo-phenotypes to explain the variability amongst healthy individuals in gut microbial flora that have important consequences for an individual's health, disease and treatment.

A review of metabolic potential of human gut microbiome in human nutrition

The human gut contains a plethora of microbes, providing a platform for metabolic interaction between the host and microbiota. Metabolites produced by the gut microbiota act as a link between gut microbiota and its host. These metabolites act as messengers having the capacity to alter the gut microbiota. Recent advances in the characterization of the gut microbiota and its symbiotic relationship with the host have provided a platform to decode metabolic interactions. The human gut microbiota, a crucial component for dietary metabolism, is shaped by the genetic, epigenetic and dietary factors. The metabolic potential of gut microbiota explains its significance in host health and diseases. The knowledge of interactions between microbiota and host metabolism, as well as modification of microbial ecology, is really beneficial to have effective therapeutic treatments for many diet-related diseases in near future. This review cumulates the information to map the role of human gut microbiota in dietary component metabolism, the role of gut microbes derived metabolites in human health and host-microbe metabolic interactions in health and diseases.

Effect of dietary supplementation with Lactobacillus acidophilus D2/CSL (CECT 4529) on caecum microbioma and productive performance in broiler chickens

This study examines the effects of the dietary supplementation with Lactobacillus acidophilus D2/CSL (CECT 4529) (LA) on productive performances, incidence of foot pad dermatitis and caecum microbioma in broiler chickens. A total of 1,100 one-day old male Ross 308 chicks were divided into 2 groups of 16 replicates with 25 birds each and reared from 1–41 d. One group was fed a basal diet (CON) and the other group the same diet supplemented with LA. Caecum contents were collected from 4 selected birds at day one and 5 selected birds at the end of the rearing period. Then, they were submitted to DNA extraction and whole DNA shotgun metagenomic sequencing. Overall, the LA supplementation produced a significant beneficial effect on body weight gain between 15–28 d and improved feed conversion rate in the overall period. On the contrary, litter moisture, pH and incidence of the foot pad lesions were not affected by LA. Birds treated with LA showed a lower occurrence of pasty vent at both 14 and 28 d. At the end of the rearing period, Lachanospiraceae were significantly higher in LA birds in comparison to CON (17.07 vs 14.39%; P = 0.036). Moreover, Ruminococcus obeum, Clostridium clostridioforme, Roseburia intestinalis, Lachnospiraceae bacterium 14-2T and Coprococcus eutactus were significantly higher in LA birds in comparison to CON. The relative abundance of Lactobacillus acidophilus was comparable between LA and CON groups. However, a positive effect was observed in relation to the metabolic functions in the treated group, with particular reference to the higher abundance of β-glucosidase. In conclusion, the LA supplementation improved broiler productive performances and metabolic functions promoting animal health.

Probiotic Lactic Acid Bacteria and Skin Health

Human skin is the first defense barrier against the external environment, especially microbial pathogens and physical stimulation. Many studies on skin health with Lactic acid bacteria (LAB) have been published for many years, including prevention of skin disease and improvement of skin conditions. LAB, a major group of gram-positive bacteria, are known to be beneficial to human health by acting as probiotics. Recent studies have shown that LAB and their extracts have beneficial effects on maintenance and improvement of skin health. Oral administration of Lactobacillus delbrueckii inhibits the development of atopic disease. In addition, LAB and LAB extracts are known to have beneficial effects on intestinal diseases, with Lactobacillus plantarum having been shown to attenuate IL-10 deficient colitis. In addition to intestinal health, L. plantarum also has beneficial effects on skin. pLTA, which is lipoteichoic acid isolated from L. plantarum, has anti-photoaging effects on human skin cells by regulating the expression matrix meralloprotionase-1 (MMP-1) expression. While several studies have proposed a relationship between diseases of the skin and small intestines, there are currently no published reviews of the effects of LAB for skin health through regulation of intestinal conditions and the immune system. In this review, we discuss recent findings on the effects of LAB on skin health and its potential applications in beauty foods.

Evaluation of a selected lactic acid bacteria-based probiotic on Salmonella enterica serovar Enteritidis colonization and intestinal permeability in broiler chickens

Two experiments were conducted to evaluate the effect of a lactic acid bacteria-based probiotic (FloraMax-B11^®) against Salmonella enterica serovar Enteritidis intestinal colonization and intestinal permeability in broiler chickens. Experiment 1 consisted of two independent trials. In each trial, day-old broiler chicks were assigned to one of two groups: control + S. Enteritidis or probiotic + S. Enteritidis. At 72 h post-S. Enteritidis challenge, haematology and caecal content were evaluated for S. Enteritidis colonization. In Experiment 2, day-old broiler chicks were assigned to one of four groups: negative control; probiotic; control + S. Enteritidis; or probiotic + S. Enteritidis. At 72 h post-S. Enteritidis challenge, chickens in all groups were given an oral gavage dose of fluorescein isothiocyanate dextran (FITC-d). In both trials of Experiment 1, a significant reduction (P < 0.05) in colony-forming units/gram of S. Enteritidis in caecal content and a reduction in the incidence of S. Enteritidis enriched caecal samples were observed in probiotic + S. Enteritidis chickens. In addition, significant heterophilia and lymphopaenia were observed in control + S. Enteritidis chickens. In Experiment 2, a decrease in numbers of S. Enteritidis in caeca were observed in probiotic + S. Enteritidis chickens when compared to control + S. Enteritidis. Also, an increase in serum FITC-d concentration was detected in control + S. Enteritidis. These results suggest that early infection with S. Enteritidis can increase intestinal permeability, but the adverse effects can be prevented by the administration of the probiotic tested.

Food-producing animals and their health in relation to human health

The fields of immunology, microbiology, and nutrition converge in an astonishing way. Dietary ingredients have a profound effect on the composition of the gut microflora, which in turn regulates the physiology of metazoans. As such, nutritional components of the diet are of critical importance not only for meeting the nutrient requirements of the host, but also for the microbiome. During their coevolution, bacterial microbiota has established multiple mechanisms to influence the eukaryotic host, generally in a beneficial fashion. The microbiome encrypts a variety of metabolic functions that complements the physiology of their hosts. Over a century ago Eli Metchnikoff proposed the revolutionary idea to consume viable bacteria to promote health by modulating the intestinal microflora. The idea is more applicable now than ever, since bacterial antimicrobial resistance has become a serious worldwide problem both in medical and agricultural fields. The impending ban of antibiotics in animal feed due to the current concern over the spread of antibiotic resistance genes makes a compelling case for the development of alternative prophylactics. Nutritional approaches to counteract the debilitating effects of stress and infection may provide producers with useful alternatives to antibiotics. Improving the disease resistance of animals grown without antibiotics will benefit the animals’ health, welfare, and production efficiency, and is also a key strategy in the effort to improve the microbiological safe status of animal-derived food products (e.g. by poultry, rabbits, ruminants, or pigs). This review presents some of the alternatives currently used in food-producing animals to influence their health in relation to human health.

Microbiome, holobiont and the net of life

Holistic emerging approaches allow us to understand that every organism is the result of integration mechanisms observed at every level of nature: integration of DNA from virus and bacteria in metazoans, endosymbiotic relationships and holobionts. Horizontal gene transfer events in Bacteria, Archaea and Eukaryotes have resulted in the chimeric nature of genomes. As a continuity of this genomic landscape, the human body contains more bacterial than human cells. Human microbiome has co-evolved with the human being as a unity called holobiont. The loss of part of our microbiome along evolution can explain the continuous increasing incidence of immune and inflammatory-related diseases. Life is a continuous process in which the organism experiences its environment and this interaction impacts in the epigenetic system and the genomic structure. The emerging perspectives restitute the great importance of Lamarck's theoretical contributions (the milieu) and Darwin's pangenesis theory.

Prokaryotes Versus Eukaryotes: Who is Hosting Whom?

Microorganisms represent the largest component of biodiversity in our world. For millions of years, prokaryotic microorganisms have functioned as a major selective force shaping eukaryotic evolution. Microbes that live inside and on animals outnumber the animals' actual somatic and germ cells by an estimated 10-fold. Collectively, the intestinal microbiome represents a "forgotten organ," functioning as an organ inside another that can execute many physiological responsibilities. The nature of primitive eukaryotes was drastically changed due to the association with symbiotic prokaryotes facilitating mutual coevolution of host and microbe. Phytophagous insects have long been used to test theories of evolutionary diversification; moreover, the diversification of a number of phytophagous insect lineages has been linked to mutualisms with microbes. From termites and honey bees to ruminants and mammals, depending on novel biochemistries provided by the prokaryotic microbiome, the association helps to metabolize several nutrients that the host cannot digest and converting these into useful end products (such as short-chain fatty acids), a process, which has huge impact on the biology and homeostasis of metazoans. More importantly, in a direct and/or indirect way, the intestinal microbiota influences the assembly of gut-associated lymphoid tissue, helps to educate immune system, affects the integrity of the intestinal mucosal barrier, modulates proliferation and differentiation of its epithelial lineages, regulates angiogenesis, and modifies the activity of enteric as well as the central nervous system. Despite these important effects, the mechanisms by which the gut microbial community influences the host's biology remain almost entirely unknown. Our aim here is to encourage empirical inquiry into the relationship between mutualism and evolutionary diversification between prokaryotes and eukaryotes, which encourage us to postulate: who is hosting whom?

Impact of probiotics on risk factors for cardiovascular diseases. A review

Probiotic microorganisms have historically been used to rebalance disturbed intestinal microbiota and to diminish gastrointestinal disorders, such as diarrhea or inflammatory bowel diseases (e.g., Crohn's disease and ulcerative colitis). Recent studies explore the potential for expanded uses of probiotics on medical disorders that increase the risk of developing cardiovascular diseases and diabetes, such as obesity, hypercholesterolemia, arterial hypertension, and metabolic disturbances such as hyperhomocysteinemia and oxidative stress. This review aims at summarizing the proposed molecular and cellular mechanisms involved in probiotic-host interactions and to identify the nature of the resulting beneficial effects. Specific probiotic strains can act by modulating immune response, by producing particular molecules or releasing biopeptides, and by modulating nervous system activity. To date, the majority of studies have been conducted in animal models. New investigations on the related mechanisms in humans need to be carried out to better enable targeted and effective use of the broad variety of probiotic strains.

Mechanisms and biological roles of contact-dependent growth inhibition systems

Bacterial contact-dependent growth inhibition (CDI) is mediated by the CdiA/CdiB family of two-partner secretion proteins. CDI(+) cells bind to susceptible target bacteria and deliver a toxic effector domain derived from the carboxyl terminus of CdiA (CdiA-CT). More than 60 distinct CdiA-CT sequence types have been identified, and all CDI toxins characterized thus far display RNase, DNase, or pore-forming activities. CDI systems also encode CdiI immunity proteins, which specifically bind and inactivate cognate CdiA-CT toxins to prevent autoinhibition. CDI activity appears to be limited to target cells of the same species, suggesting that these systems play a role in competition between closely related bacteria. Recent work on the CDI system from uropathogenic Escherichia coli (UPEC 536) has revealed that its CdiA-CT toxin binds tightly to a cysteine biosynthetic enzyme (CysK) in the cytoplasm of target cells. The unanticipated complexity in the UPEC CDI pathway raises the possibility that these systems perform other functions in addition to growth inhibition. Finally, we propose that the phenomenon of CDI is more widespread than previously appreciated. Rhs (rearrangement hotspot) systems encode toxin-immunity pairs, some of which share significant sequence identity with CdiA-CT/CdiI proteins. A number of recent observations suggest that Rhs proteins mediate a distinct form of CDI.

Implications of the human microbiome in inflammatory bowel diseases

The study of the human microbiome or community of microorganisms and collection of genomes found in the human body is one of the fastest growing research areas because many diseases are reported to be associated with microbiome imbalance or dysbiosis. With the improvement in novel sequencing techniques, researchers are now generating millions of sequences of different sites from the human body and evaluating specific differences in microbial communities. The importance of microbiome constituency is so relevant that several consortia like the Human Microbiome project (HMP) and Metagenomics of the Human Intestinal Tract (MetaHIT) project are focusing mainly on the human microbiome. The aim of this review is to highlight points of research in this field, mainly focusing on particular factors that modulate the microbiome and important insights into its potential impact on our health and well-being.

Impact of lactobacilli on orally acquired listeriosis

Listeria monocytogenes is a foodborne pathogen that crosses the intestinal barrier and disseminates within the host. Here, we report a unique comprehensive analysis of the impact of two Lactobacillus species, Lactobacillus paracasei CNCM I-3689 and Lactobacillus casei BL23, on L. monocytogenes and orally acquired listeriosis in a gnotobiotic humanized mouse model. We first assessed the effect of treatment with each Lactobacillus on L. monocytogenes counts in host tissues and showed that each decreases L. monocytogenes systemic dissemination in orally inoculated mice. A whole genome intestinal transcriptomic analysis revealed that each Lactobacillus changes expression of a specific subset of genes during infection, with IFN-stimulated genes (ISGs) being the most affected by both lactobacilli. We also examined microRNA (miR) expression and showed that three miRs (miR-192, miR-200b, and miR-215) are repressed during L. monocytogenes infection. Treatment with each Lactobacillus increased miR-192 expression, whereas only L. casei association increased miR-200b and miR-215 expression. Finally, we showed that treatment with each Lactobacillus significantly reshaped the L. monocytogenes transcriptome and up-regulated transcription of L. monocytogenes genes encoding enzymes allowing utilization of intestinal carbon and nitrogen sources in particular genes involved in propanediol and ethanolamine catabolism and cobalamin biosynthesis. Altogether, these data reveal that the modulation of L. monocytogenes infection by treatment with lactobacilli correlates with a decrease in host gene expression, in particular ISGs, miR regulation, and a dramatic reshaping of L. monocytogenes transcriptome.

Selfishness, warfare, and economics; or integration, cooperation, and biology

The acceptance of Darwin's theory of evolution by natural selection is not complete and it has been pointed out its limitation to explain the complex processes that constitute the transformation of species. It is necessary to discuss the explaining power of the dominant paradigm. It is common that new discoveries bring about contradictions that are intended to be overcome by adjusting results to the dominant reductionist paradigm using all sorts of gradations and combinations that are admitted for each case. In addition to the discussion on the validity of natural selection, modern findings represent a challenge to the interpretation of the observations with the Darwinian view of competition and struggle for life as theoretical basis. New holistic interpretations are emerging related to the Net of Life, in which the interconnection of ecosystems constitutes a dynamic and self-regulating biosphere: viruses are recognized as a macroorganism with a huge collection of genes, most unknown that constitute the major planet's gene pool. They play a fundamental role in evolution since their sequences are capable of integrating into the genomes in an “infective” way and become an essential part of multicellular organisms. They have content with “biological sense” i.e., they appear as part of normal life processes and have a serious role as carrier elements of complex genetic information. Antibiotics are cell signals with main effects on general metabolism and transcription on bacterial cells and communities. The hologenome theory considers an organism and all of its associated symbiotic microbes (parasites, mutualists, synergists, amensalists) as a result of symbiopoiesis. Microbes, helmints, that are normally understood as parasites are cohabitants and they have cohabited with their host and drive the evolution and existence of the partners. Each organism is the result of integration of complex systems. The eukaryotic organism is the result of combination of bacterial, virus, and eukaryotic DNA and it is the result of the interaction of its own genome with the genome of its microbiota, and their metabolism are intertwined (as a “superorganism”) along evolution. The darwinian paradigm had its origin in the free market theories and concepts of Malthus and Spencer. Then, nature was explained on the basis of market theories moving away from an accurate explanation of natural phenomena. It is necessary to acknowledge the limitations of the dominant dogma. These new interpretations about biological processes, molecules, roles of viruses in nature, and microbial interactions are remarkable points to be considered in order to construct a solid theory adjusted to the facts and with less speculations and tortuous semantic traps.

GanedenBC30 cell wall and metabolites: anti-inflammatory and immune modulating effects in vitro

BACKGROUND

This study was performed to evaluate anti-inflammatory and immune modulating properties of the probiotic, spore-forming bacterial strain: Bacillus coagulans: GBI-30, (PTA-6086, GanedenBC30TM). In addition, cell wall and metabolite fractions were assayed separately to address whether biological effects were due to cell wall components only, or whether secreted compounds from live bacteria had additional biological properties. The spores were heat-activated, and bacterial cultures were grown. The culture supernatant was harvested as a source of metabolites (MTB), and the bacteria were used to isolate cell wall fragments (CW). Both of these fractions were compared in a series of in vitro assays.

RESULTS

Both MTB and CW inhibited spontaneous and oxidative stress-induced ROS formation in human PMN cells and increased the phagocytic activity of PMN cells in response to bacteria-like carboxylated fluorospheres. Both fractions supported random PMN and f-MLP-directed PMN cell migration, indicating a support of immune surveillance and antibacterial defense mechanisms. In contrast, low doses of both fractions inhibited PMN cell migration towards the inflammatory mediators IL-8 and LTB4. The anti-inflammatory activity was strongest for CW, where the PMN migration towards IL-8 was inhibited down to dilutions of 1010.Both MTB and CW induced the expression of the CD69 activation marker on human CD3- CD56+ NK cells, and enhanced the expression of CD107a when exposed to K562 tumor cells in vitro.The fractions directly modulated cytokine production, inducing production of the Th2 cytokines IL-4, IL-6, and IL-10, and inhibiting production of IL-2.Both fractions further modulated mitogen-induced cytokine production in the following manner: Both fractions enhanced the PHA-induced production of IL-6 and reduced the PHA-induced production of TNF-alpha. Both fractions enhanced the PWM-induced production of TNF-alpha and IFN-gamma. In addition, MTB also enhanced both the PHA- and the PWM-induced expression of IL-10.

CONCLUSION

The data suggest that consumption of GanedenBC30TM may introduce both cell wall components and metabolites that modulate inflammatory processes in the gut. Both the cell wall and the supernatant possess strong immune modulating properties in vitro. The anti-inflammatory effects, combined with direct induction of IL-10, are of interest with respect to possible treatment of inflammatory bowel diseases as well as in support of a healthy immune system.