1,721,058 research outputs found
Uso de bacterias lácticas como vehículos de moléculas terapéuticas
No full textLa administración de moléculas terapéuticas a través de las mucosas presenta varias ventajas importantes sobre la administración sistémica clásica, tales como: reducción de efectos secundarios, fácil administración y la posibilidad de modular la respuesta inmune tanto sistémica como local. Las superficies de mucosas son los principales sitios de interacción entre un organismo y su medio ambiente y por lo tanto representan la principal puerta de entrada de patógenos. En los últimos 15 años, una gran cantidad de trabajos científicos ha reportado una variedad de vehículos de moléculas terapéuticas, vacunas principalmente, para una inmunización efectiva a nivel de mucosas. Este tipo de administración puede además, inducir una eficiente respuesta inmune sistémica con un menor riesgo de provocar efectos colaterales secundarios como lo hacen las vacunas sistémicas clásicas. Adicionalmente, la inmunización por vía mucosal se realiza de una manera más simple sin la necesidad de jeringas y agujas, eliminando así la necesidad de personal capacitado, lo cual representa una clara ventaja en programas de vacunación masiva. Sin embargo, una desventaja importante de este tipo de administración de moléculas terapéuticas, es que una gran cantidad de proteína debe ser administrada, debido al hecho de que la mayoría de la proteína será degradada en las superficies de mucosas tales como el tracto gastro-intestinal por las enzimas digestivas y las condiciones hostiles de este sitio. Por lo tanto, el desarrollo de nuevos vectores, capaces de entregar y/o expresar eficientemente moléculas terapéuticas in situ representa un reto biotecnológico.Fil: Cortes Perez, Naima G.. Institut National de la Recherche Agronomique; FranciaFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Langella, Philippe. Institut National de la Recherche Agronomique; FranciaFil: Bermudez Humaran, Luis. Institut National de la Recherche Agronomique; Franci
Implications of the human microbiome in inflammatory bowel diseases
Full text linkThe study of the human microbiome or community of microbes 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 consortialike MetaHIT and HMP 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.Fil: Bakhtiar, Syeda M.. Universidade Federal de Minas Gerais; BrasilFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina. Universidad Nacional de Tucuman. Facultad de Medicina; ArgentinaFil: Salvucci, Emiliano Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Ali, Amjad. Universidade Federal de Minas Gerais; BrasilFil: Martin, Rebeca. No especifíca;Fil: Langella, Philippe. No especifíca;Fil: Chatel, Jean Marc. No especifíca;Fil: Miyoshi, Anderson. Universidade Federal de Minas Gerais; BrasilFil: Bermudez Humaran, Luis G.. No especifíca;Fil: Azevedo, Vasco. Universidade Federal de Minas Gerais; Brasi
Current review of genetically modified lactic acid bacteria for the prevention and treatment of colitis using murine models
Full text linkInflammatory Bowel Diseases (IBD) are disorders of the gastrointestinal tract characterized by recurrent inflammation that requires lifelong treatments. Probiotic microorganisms appear as an alternative for these patients; however, probiotic characteristics are strain dependent and each probiotic needs to be tested to understand the underlining mechanisms involved in their beneficial properties. Genetic modification of lactic acid bacteria (LAB) was also described as a tool for new IBD treatments.The first part of this review shows different genetically modified LAB (GM-LAB) described for IBD treatment since 2000.Then, the two principally studied strategies are discussed (i) GM-LAB producing antioxidant enzymes and (ii) GM-LAB producing the anti-inflammatory cytokine IL-10. Different delivery systems, including protein delivery and DNA delivery, will also be discussed. Studies show the efficacy of GM-LAB (using different expression systems) for the prevention and treatment of IBD, highlighting the importance of the bacterial strain selection (with anti-inflammatory innate properties) as a promising alternative. These microorganisms could be used in the near future for the development of therapeutic products with anti-inflammatory properties that can improve the quality of life of IBD patients.Fil: de Moreno, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: del Carmen, Silvina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Chatel, Jean Marc. Institut National de la Recherche Agronomique; FranciaFil: Miyoshi, Anderson. Universidade Federal do Minas Gerais; BrasilFil: Azevedo, Vasco. Universidade Federal do Minas Gerais; BrasilFil: Langella, Philippe. Institut National de la Recherche Agronomique; FranciaFil: Bermudez Humaran, Luis G.. Institut National de la Recherche Agronomique; FranciaFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin
Evaluation of the biosafety of recombinant lactic acid bacteria designed to prevent and treat colitis
Full text linkInflammatory bowel diseases (IBDs) affect the gastrointestinal tract and are characterized by recurrent inflammation that requires lifelong therapies. Probiotics such as lactic acid bacteria (LAB) have been proposed to complement current treatment protocols for these patients; however, their characteristics are strain dependent. In this regard, certain novel characteristics are only possible through the genetic modification of these beneficial micro-organisms. Different delivery systems, such as protein delivery of anti-oxidant enzymes and anti-inflammatory cytokines, have been shown to be effective in preventing and treating IBD in animal models. In this study, the safety of the recombinant LAB (recLAB) Streptococcus thermophilus CRL807: CAT, S. thermophilus CRL807: SOD, Lactococcus lactis NCDO2118 pXILCYT: IL-10, L. lactis MG1363 pValac: IL-10 and L. lactis MG1363 pGroESL: IL-10 with proven beneficial effects was compared to their progenitor strains S. thermophilus CRL807, L. lactis NCDO2118 or L. lactis MG1363. The prolonged administration of these genetically modified strains showed that they were just as safe as the native strains from which they derive, as demonstrated by normal animal growth and relative organ weights, absence of microbial translocation from the gastrointestinal tract, normal blood parameters and intestinal histology. The results show the potential use of these recLAB in future therapeutic formulations; however, the use of modern bio-containment systems is required for the future acceptance of these recLAB by the medical community and patients with IBD.Fil: de Moreno, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: del Carmen, Silvina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Chatel, Jean Marc. INRA and AgroParisTech; FranciaFil: Azevedo, Vasco. Universidade Federal do Minas Gerais; BrasilFil: Langella, Philippe. INRA and AgroParisTech; FranciaFil: Bermudez Humaran, Luis. INRA and AgroParisTech; FranciaFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin
Gnotobiotic rodents: an in vivo model for the study of microbe-microbe interactions
No full textGerm-free rodents have no microorganisms living in or on them, allowing researchers to specifically control an animal's microbiota through the direct inoculation of bacteria of interest. This strategy has been widely used to decipher host microbe interactions as well as the role of microorganisms in both (i) the development and function of the gut barrier (mainly the intestinal epithelium) and (ii) homeostasis and its effects on human health and disease. However, this in vivo model also offers a more realistic environment than an assay tube in which to study microbe microbe interactions, without most of the confounding interactions present in the intestinal microbiota of conventionally raised mice. This review highlights the usefulness of controlled-microbiota mice in studying microbe microbe interactions. To this end, we summarize current knowledge on germ free animals as an experimental model for the study of the ecology and metabolism of intestinal bacteria as well as of microbe microbe interactions
Anti-inflammatory properties of lactic acid bacteria: Current knowledge, applications and prospects
Full text linkLactic acid bacteria (LAB) represent a heterogeneous group of microorganisms that are naturally present in many foods. Some selected strains are frequently added as probiotics in order to confer specific benefits to consumers. Many studies have shown that LAB possess therapeutic properties since they are able to prevent the development of some diseases, as shown mostly on animal models for cancer, infections and gastrointestinal disorders such as intestinal inflammation. They have been shown to regulate mucosal immune responses by modulating the production and liberation of regulatory agents such as cytokines by the host. Some of these cytokines, such as the anti-inflammatory interleukin-10 (IL-10), modulate the inflammatory immune response, thus immunomodulation is a mechanism by which LAB can prevent certain inflammatory bowel diseases (IBD). Since oxidative stress participates to the inflammatory processes and to the appearance of damages in pathologies of the gastrointestinal tract of humans such as IBD, LAB could also prevent inflammation by eliminating reactive oxygen species (ROS) through the activity of antioxidant enzymes. Engineering LAB to produce either antioxidant enzymes (such as catalases and superoxide dismutases) or anti-inflammatory cytokines (such as IL-10) is a strategy currently exploited by several groups. These novel strains have successfully been used to prevent inflammatory bowel diseases in animal models and could be evaluated in human clinical trials. Here, we present an overview of the current knowledge of the mechanisms by which LAB can be used to prevent undesired intestinal inflammatory responses.Fil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: de Moreno, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Perdigon, Gabriela del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Miyoshi, Anderson. Universidade Federal de Minas Gerais; BrasilFil: Rochat, Tatiana. Institut National de la Recherche Agronomique; FranciaFil: Bermudez Humaran, Luis. Institut National de la Recherche Agronomique; FranciaFil: Langella, Philippe. Institut National de la Recherche Agronomique; FranciaFil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Azevedo, Vasco. Universidade Federal de Minas Gerais; Brasi
Milk fermented with a 15-lipoxygenase-1-producing lactococcus lactis alleviates symptoms of colitis in a murine model
Full text linkInflammatory bowel diseases (IBD), such as Crohn's 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.Fil: Saraiva, Tessália D. L.. Universidade Federal do Minas Gerais; BrasilFil: Morais, Kátia. Universidade Federal do Minas Gerais; BrasilFil: Pereira, Vanessa B.. Universidade Federal do Minas Gerais; BrasilFil: de Azevedo, Marcela. Universidade Federal do Minas Gerais; BrasilFil: Santos Rocha, Clarissa. Universidade Federal do Minas Gerais; BrasilFil: Castro Prosperi, Camila. Universidade Federal do Minas Gerais; BrasilFil: Gomes Santos, Ana C.. Universidade Federal do Minas Gerais; BrasilFil: Bermudez Humaran, Luis. Institut National de la Recherche Agronomique; FranciaFil: Caetano Faria, Ana M.. Universidade Federal do Minas Gerais; BrasilFil: Blottiere, Hervé M.. Institut National de la Recherche Agronomique; FranciaFil: Langella, Philippe. Institut National de la Recherche Agronomique; FranciaFil: Miyoshi, Anderson. Universidade Federal do Minas Gerais; BrasilFil: de Moreno, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Azevedo, Vasco. Universidade Federal do Minas Gerais; Brasi
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
From probiotics to psychobiotics: live beneficial bacteria which act on the brain-gut axis
No full textThere is an important relationship between probiotics, psychobiotics and cognitive and behavioral processes, which include neurological, metabolic, hormonal and immunological signaling pathways; the alteration in these systems may cause alterations in behavior (mood) and cognitive level (learning and memory). Psychobiotics have been considered key elements in affective disorders and the immune system, in addition to their effect encompassing the regulation of neuroimmune regulation and control axes (the hypothalamic-pituitary-adrenal axis or HPA, the sympathetic-adrenal-medullary axis or SAM and the inflammatory reflex) in diseases of the nervous system. The aim of this review is to summarize the recent findings about psychobiotics, the brain-gut axis and the immune system. The review focuses on a very new and interesting field that relates the microbiota of the intestine with diseases of the nervous system and its possible treatment, in neuroimmunomodulation area. Indeed, although probiotic bacteria will be concentrated after ingestion, mainly in the intestinal epithelium (where they provide the host with essential nutrients and modulation of the immune system), they may also produce neuroactive substances which act on the brain-gut axis
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