Clarissa Santos Rocha

Anti‐inflammatory properties of dairy lactobacilli

Background: The intestinal microbiota plays an important role in human health through the modulation of innate immune responses. While selected commensal bacteria are marketed in specific probiotic products to control these responses, relatively little is known about the immune modulation potential of dairy bacteria that have principally been selected for their fermentation properties. The modulation of innate immune responses may reduce chronic inflammation in inflammatory bowel diseases like ulcerative colitis. Methods: A collection of dairy Lactobacillus delbrueckii strains was screened for immune modulation effects in vitro through the quantification of nuclear factor kappa B (NF‐&kgr;B) activation in a human intestinal epithelial cell line. Selected bacterial strains were then tested in vivo in a mouse dextran sodium sulfate (DSS) colitis model. Results: All L. delbrueckii strains tested showed anti‐inflammatory effects in vitro, to an extent that varied between strains. These effects rely on bacterial surface exposed proteins and affect the central part of the NF‐&kgr;B activation pathway. One of the selected strains significantly reduced the macroscopic and microscopic symptoms of DSS‐induced colitis in the mouse intestinal tract, diminished body weight loss, and improved survival. Conclusions: The results of this study show that dairy lactobacilli that often are part of a regular diet can modulate innate immune responses, and may thus affect health more than generally thought. One of the strains tested alleviated the symptoms of DSS‐induced colitis in mice, a model of human ulcerative colitis. (Inflamm Bowel Dis 2011;)

Importance of IL-10 Modulation by Probiotic Microorganisms in Gastrointestinal Inflammatory Diseases

Lactic acid bacteria (LAB) represent a heterogeneous group of microorganisms that are naturally present in many foods and possess a wide range of therapeutic properties. The aim of this paper is to present an overview of the current expanding knowledge of one of the mechanisms by which LAB and other probiotic microorganisms participate in the prevention and treatment of gastrointestinal inflammatory disease through their immune-modulating properties. A special emphasis will be placed on the critical role of the anti-inflammatory cytokine IL-10, and a brief overview of the uses of genetically engineered LAB that produce this important immune response mediator will also be discussed. Thus, this paper will demonstrate the critical role that IL-10 plays in gastrointestinal inflammatory diseases and how probiotics could be used in their treatment.

Local and systemic immune mechanisms underlying the anti-colitis effects of the dairy bacterium Lactobacillus delbrueckii.

Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD), showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327), also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS) colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-β, IL-6, and IL-12 in colonic tissue and of TGF-β and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.

Immunotherapy of allergic diseases using probiotics or recombinant probiotics.

Allergic diseases affect up to 30% of the western population, and their prevalence is increasing. Probiotics are able to modulate the mucosal immune response, and clinical trials demonstrated that specific strains, especially lactic acid bacteria (LAB) ones, reduce allergic symptoms. Moreover, the use of recombinant probiotics has been evaluated as possible strategies for the immunotherapy of allergic diseases. The production and delivery of allergens by recombinant LAB in concert with their ability to induce a Th1‐type immune response have been shown to be a promising mucosal vaccination strategy in mouse model. The aim of this article is to review the applications of probiotics in allergy immunotherapy with a special focus on recombinant LAB delivering proteins or DNA.

Genome Sequence of Lactococcus lactis subsp. lactis NCDO 2118, a GABA-Producing Strain

ABSTRACT Lactococcus lactis subsp. lactis NCDO 2118 is a nondairy lactic acid bacterium, a xylose fermenter, and a gamma-aminobutyric acid (GABA) producer isolated from frozen peas. Here, we report the complete genome sequence of L. lactis NCDO 2118, a strain with probiotic potential activity.

Potential Application of Probiotics in the Prevention and Treatment of Inflammatory Bowel Diseases

Lactic acid bacteria (LAB) represent a heterogeneous group of microorganisms that are naturally present in many foods and possess a wide range of therapeutic properties. The aim of this paper is to present an overview of the current expanding knowledge of the mechanisms by which LAB and other probiotic microorganisms participate in the prevention and treatment of inflammatory bowel diseases. These include changes in the gut microbiota, stimulation of the host immune responses, and reduction of the oxidative stress due to their antioxidant properties. A brief overview of the uses of genetically engineered LAB that produce either antioxidant enzymes (such as catalase and superoxide dismutase) or anti-inflammatory cytokines (such as IL-10) will also be discussed. This paper will show that probiotics should be considered in treatment protocols of IBD since they provide many beneficial effects and can enhance the effectiveness of traditional used medicines.

Milk Fermented with a 15-Lipoxygenase-1-Producing Lactococcus Lactis Alleviates Symptoms of colitis in a Murine Model

Inflammatory bowel diseases (IBD), such as Crohns disease and ulcerative colitis, is characterized by extensive inflammation due to dysregulation of the innate and adaptive immune system whose exact etiology is not yet completely understood. Currently there is no cure for IBD, thus the search for new molecules capable of controlling IBD and their delivery to the site of inflammation are the goal of many researchers. The aim of this work was to evaluate the anti-inflammatory effect of the administration of milks fermented by a Lactococcus (L.) lactis strain producing 15-lipoxygenase-1 (15-LOX-1) using a trinitrobenzenesulfonic acid-induced IBD mouse model. The results obtained demonstrated that 15-LOX-1 producing L. lactis was effective in the prevention of the intestinal damage associated to inflammatory bowel disease in a murine model. The work also confirmed previous studies showing that fermented milk is an effective form of administration of recombinant lactic acid bacteria expressing beneficial molecules.

Ornithine decarboxylase expression in the small intestine of broilers submitted to feed restriction and glutamine supplementation

Six hundred and forty one-day-old Cobb male broilers were used to evaluate ornithine decarboxylase (ODC) expression in the mucosa of the small intestine. Birds were submitted to early feed restriction from 7 to 14 days of age. The provided feed was supplemented with glutamine. A completely randomized design with a 2 x 2 factorial arrangement was used (with or without glutamine, with or without feed restriction). Restricted-fed birds were fed at 30% the amount of the ad libitum fed group from 7 to 14 days of age. Glutamine was added at the level of 1% in the diet supplied from 1 to 28 days of age. Protein concentration in the small intestine mucosa was determined, and ODC expression at 7, 14, 21, and 28 days of age was evaluated by dot blotting. ODC was present in the mucosa of broilers, and the presence of glutamine in the diet increased ODC activation. Glutamine prevented mucosa atrophy by stimulating protein synthesis, and was effective against the effects of feed restriction. Dot blotting can be used to quantify ODC expression in the intestinal mucosa of broilers.

Microbial Omics: Applications in Biotechnology

Abstract Omics studies are the global analysis of biologic systems that are explored intensively due to the large number of known genomes that involve the knowledge of structural and functional genomics. In this chapter, the subject of omics approaches related to microbial biotechnology, which encompasses various sciences, will be addressed along with their applications in a variety of fields: medical, agricultural, industrial, and environmental applications. This chapter starts with a brief introduction concerning the theme. Section 1.2 covers genome sequencing, comparative genomics, pan-genomics, and immunogenomics. Section 1.3 deals with transcriptomics, proteomics, metabolomics, and interactomics, to understand the organism better. This also comprises isolating and characterizing the genes, proteins, and metabolites and analyzing the interaction between them. Finally, this chapter focuses on the conclusions and the perspectives about this subject.