scholarly journals Propionibacterium freudenreichii: General Characteristics and Probiotic Traits

2021 ◽  
Author(s):  
Vinícius de Rezende Rodovalho ◽  
Diego Lucas Neres Rodrigues ◽  
Gwénaël Jan ◽  
Yves Le Loir ◽  
Vasco Ariston de Carvalho Azevedo ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Bacterial Species ◽  
Short Chain Fatty Acids ◽  
Surface Proteins ◽  
Propionibacterium Freudenreichii ◽  
Long Time ◽  
Beneficial Traits

Propionibacterium freudenreichii is a Gram-positive dairy probiotic bacterial species that has been used as a ripening starter in the production of Swiss-type cheese for a long time. It has been exploited for the optimization of cheese production, including ripening capacities and aroma compounds production, but also for the production of vitamin B12 and organic acids. Furthermore, it has emerged in the probiotics landscape owing to several beneficial traits, including tolerance to stress in the gastrointestinal tract, adhesion to host cells, anti-pathogenic activity, anticancer potential and immunomodulatory properties. These beneficial properties have been confirmed with in vitro and in vivo investigations, using several omics approaches that allowed the identification of important molecular actors, such as surface proteins, short-chain fatty acids and bifidogenic factors. The diversity within the species was shown to be an important aspect to take into consideration, since many of these properties were strain-dependent. New studies should dive further into the molecular mechanisms related to the beneficial properties of this species and of its products, while considering the complexities of strain diversity and the interactions with the host and its microbiota. This chapter reviews current knowledge on the possible impact of P. freudenreichii on human health.

scholarly journals Identification of Functional LsrB-Like Autoinducer-2 Receptors

2009 ◽  
Vol 191 (22) ◽  
pp. 6975-6987 ◽  
Author(s):  
Catarina S. Pereira ◽  
Anna K. de Regt ◽  
Patrícia H. Brito ◽  
Stephen T. Miller ◽  
Karina B. Xavier
Keyword(s):  
Structure Prediction ◽  
Molecular Mechanisms ◽  
Bacterial Species ◽  
Autoinducer 2 ◽  
Communication Signal ◽  
Independent Events ◽  
Key Species ◽  
Serovar Typhimurium

ABSTRACT Although a variety of bacterial species have been reported to use the interspecies communication signal autoinducer-2 (AI-2) to regulate multiple behaviors, the molecular mechanisms of AI-2 recognition and signal transduction remain poorly understood. To date, two types of AI-2 receptors have been identified: LuxP, present in Vibrio spp., and LsrB, first identified in Salmonella enterica serovar Typhimurium. In S. Typhimurium, LsrB is the ligand binding protein of a transport system that enables the internalization of AI-2. Here, using both sequence analysis and structure prediction, we establish a set of criteria for identifying functional AI-2 receptors. We test our predictions experimentally, assaying key species for their abilities to import AI-2 in vivo, and test their LsrB orthologs for AI-2 binding in vitro. Using these experimental approaches, we were able to identify AI-2 receptors in organisms belonging to phylogenetically distinct families such as the Enterobacteriaceae, Rhizobiaceae, and Bacillaceae. Phylogenetic analysis of LsrB orthologs indicates that this pattern could result from one single origin of the functional LsrB gene in a gammaproteobacterium, suggesting possible posterior independent events of lateral gene transfer to the Alphaproteobacteria and Firmicutes. Finally, we used mutagenesis to show that two AI-2-interacting residues are essential for the AI-2 binding ability. These two residues are conserved in the binding sites of all the functional AI-2 binding proteins but not in the non-AI-2-binding orthologs. Together, these results strongly support our ability to identify functional LsrB-type AI-2 receptors, an important step in investigations of this interspecies signal.

scholarly journals Anti-Cancer Effects of Green Tea Polyphenols Against Prostate Cancer

Molecules ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 193 ◽  
Author(s):  
Yasuyoshi Miyata ◽  
Yohei Shida ◽  
Tomoaki Hakariya ◽  
Hideki Sakai
Keyword(s):  
Prostate Cancer ◽  
Green Tea ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Tea Polyphenols ◽  
Green Tea Polyphenols ◽  
Anti Cancer ◽  
Prevention And Treatment

Prostate cancer is the most common cancer among men. Green tea consumption is reported to play an important role in the prevention of carcinogenesis in many types of malignancies, including prostate cancer; however, epidemiological studies show conflicting results regarding these anti-cancer effects. In recent years, in addition to prevention, many investigators have shown the efficacy and safety of green tea polyphenols and combination therapies with green tea extracts and anti-cancer agents in in vivo and in vitro studies. Furthermore, numerous studies have revealed the molecular mechanisms of the anti-cancer effects of green tea extracts. We believe that improved understanding of the detailed pathological roles at the molecular level is important to evaluate the prevention and treatment of prostate cancer. Therefore, in this review, we present current knowledge regarding the anti-cancer effects of green tea extracts in the prevention and treatment of prostate cancer, with a particular focus on the molecular mechanisms of action, such as influencing tumor growth, apoptosis, androgen receptor signaling, cell cycle, and various malignant behaviors. Finally, the future direction for the use of green tea extracts as treatment strategies in patients with prostate cancer is introduced.

scholarly journals Phage Therapy as a Focused Management Strategy in Aquaculture

2021 ◽  
Vol 22 (19) ◽  
pp. 10436
Author(s):  
José Ramos-Vivas ◽  
Joshua Superio ◽  
Jorge Galindo-Villegas ◽  
Félix Acosta
Keyword(s):  
Bacterial Infections ◽  
Therapeutic Potential ◽  
Current Knowledge ◽  
Control Strategies ◽  
Bacterial Species ◽  
Lytic Enzymes ◽  
Wide Range ◽  
Cultured Fish

Therapeutic bacteriophages, commonly called as phages, are a promising potential alternative to antibiotics in the management of bacterial infections of a wide range of organisms including cultured fish. Their natural immunogenicity often induces the modulation of a variated collection of immune responses within several types of immunocytes while promoting specific mechanisms of bacterial clearance. However, to achieve standardized treatments at the practical level and avoid possible side effects in cultivated fish, several improvements in the understanding of their biology and the associated genomes are required. Interestingly, a particular feature with therapeutic potential among all phages is the production of lytic enzymes. The use of such enzymes against human and livestock pathogens has already provided in vitro and in vivo promissory results. So far, the best-understood phages utilized to fight against either Gram-negative or Gram-positive bacterial species in fish culture are mainly restricted to the Myoviridae and Podoviridae, and the Siphoviridae, respectively. However, the current functional use of phages against bacterial pathogens of cultured fish is still in its infancy. Based on the available data, in this review, we summarize the current knowledge about phage, identify gaps, and provide insights into the possible bacterial control strategies they might represent for managing aquaculture-related bacterial diseases.

scholarly journals Seaweed Components as Potential Modulators of the Gut Microbiota

Marine Drugs ◽  
2021 ◽  
Vol 19 (7) ◽  
pp. 358
Author(s):  
Emer Shannon ◽  
Michael Conlon ◽  
Maria Hayes
Keyword(s):  
Gut Microbiota ◽  
Large Scale ◽  
Current Knowledge ◽  
Ex Vivo ◽  
Short Chain Fatty Acids ◽  
In Vivo Studies ◽  
Therapeutic Effects ◽  
Oral Bioaccessibility

Macroalgae, or seaweeds, are a rich source of components which may exert beneficial effects on the mammalian gut microbiota through the enhancement of bacterial diversity and abundance. An imbalance of gut bacteria has been linked to the development of disorders such as inflammatory bowel disease, immunodeficiency, hypertension, type-2-diabetes, obesity, and cancer. This review outlines current knowledge from in vitro and in vivo studies concerning the potential therapeutic application of seaweed-derived polysaccharides, polyphenols and peptides to modulate the gut microbiota through diet. Polysaccharides such as fucoidan, laminarin, alginate, ulvan and porphyran are unique to seaweeds. Several studies have shown their potential to act as prebiotics and to positively modulate the gut microbiota. Prebiotics enhance bacterial populations and often their production of short chain fatty acids, which are the energy source for gastrointestinal epithelial cells, provide protection against pathogens, influence immunomodulation, and induce apoptosis of colon cancer cells. The oral bioaccessibility and bioavailability of seaweed components is also discussed, including the advantages and limitations of static and dynamic in vitro gastrointestinal models versus ex vivo and in vivo methods. Seaweed bioactives show potential for use in prevention and, in some instances, treatment of human disease. However, it is also necessary to confirm these potential, therapeutic effects in large-scale clinical trials. Where possible, we have cited information concerning these trials.

scholarly journals Cancer Initiation, Progression and Resistance: Are Phytocannabinoids from Cannabis sativa L. Promising Compounds?

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2668
Author(s):  
Ersilia Nigro ◽  
Marialuisa Formato ◽  
Giuseppina Crescente ◽  
Aurora Daniele
Keyword(s):  
Molecular Mechanisms ◽  
Cannabinoid Receptors ◽  
Cannabis Sativa ◽  
Current Knowledge ◽  
Endocannabinoid System ◽  
Peripheral Tissues ◽  
Positive Effects ◽  
Cancer Initiation

Cannabis sativa L. is a source of over 150 active compounds known as phytocannabinoids that are receiving renewed interest due to their diverse pharmacologic activities. Indeed, phytocannabinoids mimic the endogenous bioactive endocannabinoids effects through activation of CB1 and CB2 receptors widely described in the central nervous system and peripheral tissues. All phytocannabinoids have been studied for their protective actions towards different biological mechanisms, including inflammation, immune response, oxidative stress that, altogether, result in an inhibitory activity against the carcinogenesis. The role of the endocannabinoid system is not yet completely clear in cancer, but several studies indicate that cannabinoid receptors and endogenous ligands are overexpressed in different tumor tissues. Recently, in vitro and in vivo evidence support the effectiveness of phytocannabinoids against various cancer types, in terms of proliferation, metastasis, and angiogenesis, actions partially due to their ability to regulate signaling pathways critical for cell growth and survival. The aim of this review was to report the current knowledge about the action of phytocannabinoids from Cannabis sativa L. against cancer initiation and progression with a specific regard to brain, breast, colorectal, and lung cancer as well as their possible use in the therapies. We will also report the known molecular mechanisms responsible for such positive effects. Finally, we will describe the actual therapeutic options for Cannabis sativa L. and the ongoing clinical trials.

Investigating the Biological and Molecular Mechanisms Underpinning the Engraftment/Selection Advantage Conferred to Hematopoietic Stem Cells by HOXB4.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2101-2101
Author(s):  
Michael D. Milsom ◽  
Laura Hollins ◽  
Dorothy Gagen ◽  
Lorna B. Woolford ◽  
Leslie J. Fairbairn
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Cellular Transformation ◽  
Model Systems ◽  
Self Renewal ◽  
Hematopoietic Stem ◽  
Increased Risk ◽  
Vitro Analysis

Abstract We have recently demonstrated that co-expression of HOXB4 enables the enhanced delivery of HSC harbouring a second therapeutic trans-gene. Nonetheless, it is of great importance to elaborate the current knowledge about the mechanism of HOXB4 action in order to both evaluate the safety implications of its use in a clinical strategy, and to gain greater insight into the regulation of HSC self-renewal/expansion. To these ends we have performed an extensive in vitro analysis of the consequences of HOXB4 overexpression in primary murine BMC and in a murine multipotent myeloid progenitor cell line (FDCP-mix). We demonstrate for the first time in murine cells, that ectopic HOXB4 reduces the responsiveness of murine hematopoietic cells to differentiation stimuli. Furthermore, by performing a detailed investigation into the kinetics of FDCP-mix differentiation, we reveal that HOXB4 overexpression results in a specific differentiation delay as opposed to an outright block. We propose that an analogous delay is in operation in repopulating cells in order that the shift to increased assymetrical self-renewal, a requirement for stem cell expansion, is achieved. Notwithstanding this, it is clear that any perturbation in differentiation constitutes an increased risk of cellular transformation if this technology were transferred to a clinical setting. In order to further define the repercussions of ectopic HOXB4 delivery, we have developed a retroviral vector which encodes an activatable version of HOXB4. We have shown that this vector is able to mediate an in vitro differentiation delay in primary murine BMC and FDCP-mix as well as enable enhanced engraftment of BMC in vivo, both dependent upon the addition of the estrogen analogue; tamoxifen. Using this system, we are currently examining the effect of ectopic HOXB4 on the transcriptome of FDCP-mix cells, in addition to performing an in depth study into the biological mechanisms affected by HOXB4 overexpression in BMC in vivo. We envisage that these model systems will be particularly amenable to the manipulation required for target gene identification/validation.

scholarly journals The Impact of Acute or Chronic Alcohol Intake on the NF-κB Signaling Pathway in Alcohol-Related Liver Disease

2020 ◽  
Vol 21 (24) ◽  
pp. 9407
Author(s):  
Aleksander J. Nowak ◽  
Borna Relja
Keyword(s):  
Liver Disease ◽  
Signaling Pathway ◽  
Molecular Mechanisms ◽  
Inflammatory Responses ◽  
Current Knowledge ◽  
In Vivo Studies ◽  
Related Liver Disease ◽  
The Impact

Ethanol misuse is frequently associated with a multitude of profound medical conditions, contributing to health-, individual- and social-related damage. A particularly dangerous threat from this classification is coined as alcoholic liver disease (ALD), a liver condition caused by prolonged alcohol overconsumption, involving several pathological stages induced by alcohol metabolic byproducts and sustained cellular intoxication. Molecular, pathological mechanisms of ALD principally root in the innate immunity system and are especially associated with enhanced functionality of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. NF-κB is an interesting and convoluted DNA transcription regulator, promoting both anti-inflammatory and pro-inflammatory gene expression. Thus, the abundancy of studies in recent years underlines the importance of NF-κB in inflammatory responses and the mechanistic stimulation of inner molecular motifs within the factor components. Hereby, in the following review, we would like to put emphasis on the correlation between the NF-κB inflammation signaling pathway and ALD progression. We will provide the reader with the current knowledge regarding the chronic and acute alcohol consumption patterns, the molecular mechanisms of ALD development, the involvement of the NF-κB pathway and its enzymatic regulators. Therefore, we review various experimental in vitro and in vivo studies regarding the research on ALD, including the recent active compound treatments and the genetic modification approach. Furthermore, our investigation covers a few human studies.

Challenges in translational research on probiotic lactobacilli: from in vitro assays to clinical trials

2013 ◽  
Vol 4 (1) ◽  
pp. 83-100 ◽  
Author(s):  
M. Meijerink ◽  
A. Mercenier ◽  
J.M. Wells
Keyword(s):  
Translational Research ◽  
Selection Criteria ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Intestinal Barrier ◽  
Probiotic Strain ◽  
In Vitro Assays ◽  
Intestinal Barrier Function

Beneficial effects of certain probiotic strains have been established in the treatment and prevention of various immune and intestinal disorders in humans, including allergic diseases, chronic inflammatory diseases and diarrhoea. The proposed mechanisms underlying the immunomodulatory effects of probiotics in humans are not understood in precise detail but include enhancement of intestinal barrier function, altered epithelial signalling, competition with pathogens and effects on immune cells and immunity depending on the probiotic strain. The publication of controversial or inconclusive probiotic studies in humans highlights the need for a better understanding of the mechanisms and improved strain selection criteria. This review focuses on the immunomodulatory properties of lactobacilli and bifidobacteria in vitro and in vivo, current knowledge concerning the mechanisms in vivo and challenges in translational research on probiotics. A better understanding of the molecular mechanisms of probiotics, the effect of probiotic mixtures versus single strains, the effect of formulation of probiotics and the fate of ingested probiotics should help to clarify the value of immune assays as selection criteria for probiotics.

scholarly journals Licorice in the Treatment of Acne Vulgaris and Postinflammatory Hyperpigmentation: A Review

2021 ◽  
Author(s):  
Kosar Raoufinejad ◽  
Mehdi Rajabi
Keyword(s):  
Clinical Trials ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Acne Vulgaris ◽  
Controlled Clinical Trials ◽  
Pharmacological Activities ◽  
Postinflammatory Hyperpigmentation ◽  
Licorice Extract

Clinical advantages of licorice (Glycyrrhiza spp.) have been investigated for several years. It has been traditionally used for a variety of disorders. Different constituents with various characteristics have been isolated from Glycyrrhiza spp. extracts. This review aimed to summarize the current knowledge on the pharmacological efficacy and safety of licorice extract constituents to treat the pathophysiology of acne vulgaris (AV) and the associated postinflammatory hyperpigmentation (PIH). Anti-androgenic, antimicrobial, anti-inflammatory, antioxidant, depigmenting, and skinturnover-accelerating properties have been identified for licorice extract which could be effective against AV and PIH through multiple pharmacological mechanisms. The active compounds responsible for these pharmacological activities, molecular mechanisms, safety profile, as well as the in vitro, in vivo, animal, and clinical studies are discussed. Licorice extract possesses broadspectrum activity and could be considered as an effective and safe option in the treatment of AV and its associated PIH. However, evidence-based clinical trials are required to prove its efficacy as well as safety. We hope this paper can provide new insights for further studies, particularly large controlled clinical trials.

scholarly journals Human blastocyst outgrowths recapitulate primordial germ cell specification events

2019 ◽  
Vol 25 (9) ◽  
pp. 519-526 ◽  
Author(s):  
Mina Popovic ◽  
Monika Bialecka ◽  
Maria Gomes Fernandes ◽  
Jasin Taelman ◽  
Margot Van Der Jeught ◽  
...  
Keyword(s):  
Germ Cell ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Descriptive Analysis ◽  
Primordial Germ Cell ◽  
Human Embryos ◽  
Embryo Viability ◽  
Germ Cell Specification

Abstract Our current knowledge of the mechanisms leading to human primordial germ cell (PGC) specification stems solely from differentiation experiments starting from human pluripotent stem cells. However, information regarding the origin of PGCs in vivo remains obscure. Here we apply an improved system for extended in vitro culture of human embryos to investigate the presence of PGC-like cells (PGCLCs) 12 days post fertilization (dpf). Good quality blastocysts (n = 141) were plated at 6 dpf and maintained in hypoxia, in medium supplemented with Activin A until 12 dpf. We primarily reveal that 12 dpf outgrowths recapitulate human peri-implantation events and demonstrate that blastocyst quality significantly impacts both embryo viability at 12 dpf, as well as the presence of POU5F1+ cells within viable outgrowths. Moreover, detailed examination of 12 dpf blastocyst outgrowths revealed a population of POU5F1+, SOX2– and SOX17+ cells that may correspond to PGCLCs, alongside POU5F1+ epiblast-like cells and GATA6+ endoderm-like cells. Our findings suggest that, in human, PGC precursors may become specified within the epiblast and migrate either transiently to the extra-embryonic mesoderm or directly to the dorsal part of the yolk sac endoderm around 12 dpf. This is a descriptive analysis and as such the conclusion that POU5F1+ and SOX17+ cells represent bona fide PGCs can only be considered as preliminary. In the future, other PGC markers may be used to further validate the observed cell populations. Overall, our findings provide insights into the origin of the human germline and may serve as a foundation to further unravel the molecular mechanisms governing PGC specification in human.

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