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Ligilactobacillus salivarius is a lactic acid bacterium exhibiting several health benefits. However, it is sensitive to freeze-drying and storage in the dried state, thus limiting its commercial exploitation. Our objective was to identify markers of cell resistance by applying multiscale characterization to L. salivarius CECT5713 cell populations exhibiting different resistance to freeze-dried storage. Cells were produced under two different sets of production conditions differing in the culture parameters (temperature, neutralizing solution, and harvesting time) and the protective formulation composition. The culturability, membrane integrity, and cell biochemical composition assessed by Fourier transform infrared (FTIR) micro-spectroscopy were evaluated after freezing, freeze-drying, and subsequent storage at 37 °C. Membrane properties (fatty acid composition, membrane fluidity, and phospholipid organization), as well as matrix physical properties (glass transition temperature and water activity), were determined. The most resistant cells to freeze-dried storage exhibited the highest cyclic fatty acid content and the most rigid membrane. Freeze-drying and storage induced damage to membrane integrity, proteins, nucleic acids, and constituents of the peptidoglycan cell wall. From the FTIR spectra analysis, we propose the minimization of the variations of the 1058 and 1714 cm-1 vibration bands (that arise mainly from symmetric C-O-C stretching and CO stretching, respectively) induced by the freeze-drying process as a marker of storage stability. We confirmed that a matrix with a glass transition temperature at least 50 °C higher than the storage temperature is crucial for L. salivarius CECT5713 storage stability. In addition, this work explored promising FTIR methods for a better understanding of the protection mechanisms involved.
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Criopreservação , Ácidos Graxos , Congelamento , Criopreservação/métodos , Liofilização/métodos , TemperaturaRESUMO
Ligilactobacillus salivarius is a lactic acid bacterium exhibiting several health benefits but remains commercially underexploited due to its inability to survive during long-term storage in the dried state. Our objective was to study the effect of various protective molecules (maltodextrin, trehalose, antioxidants, and fructooligosaccharides), being efficient on other bacteria, on the freeze-dried stability of L. salivarius CECT5713. The culturability was evaluated after freezing, freeze-drying, and subsequent storage at 37 °C, as well as the biochemical composition of cells in an aqueous environment using Fourier transform infrared (FTIR) micro-spectroscopy. The assignment of principal absorption bands to cellular components was performed using data from the literature on bacteria. The membrane fatty acid composition was determined after freeze-drying and storage. Glass transition temperature of the liquid and freeze-dried bacterial suspensions and water activity of the freeze-dried samples were measured. The best storage stability was observed for the formulations involving maltodextrin and antioxidants. The analysis of the FTIR spectra of freeze-thawed cells and rehydrated cells after freeze-drying and storage revealed that freeze-drying induced damage to proteins, peptidoglycans of the cell wall and nucleic acids. Storage stability appeared to be dependent on the ability of the protective molecules to limit damage during freeze-drying. The inactivation rates of bacteria during storage were analyzed as a function of the temperature difference between the product temperature during sublimation or during storage and the glass transition temperature, allowing a better insight into the stabilization mechanisms of freeze-dried bacteria. Maintaining during the process a product temperature well below the glass transition temperature, especially during storage, appeared essential for L. salivarius CECT5713 storage stability. KEY POINTS: ⢠L. salivarius CECT5713 highly resisted freezing but was sensitive to freeze-drying and storage. ⢠Freeze-drying and storage mainly altered cell proteins, peptidoglycans, and nucleic acids. ⢠A glassy matrix containing maltodextrin and an antioxidant ensured the highest storage stability.
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Ácidos Nucleicos , Trealose , Antioxidantes , Liofilização/métodos , Proteínas/química , Água , Ácido Láctico , Ácidos GraxosRESUMO
Following the spread of the SARS-CoV-2 coronavirus, an unprecedented burden has been placed on health care systems, with health care workers (HCWs) being most at risk of COVID-19 infection. The effect of the probiotic Loigolactobacillus coryniformis K8 CECT 5711 on frontline HCWs exposed to the virus was studied in a randomized, double-blind, placebo controlled trial. Parameters related to the incidence and severity of COVID-19 as well as the immune response and the side effects of the COVID-19 vaccine were evaluated. For 2 months, a group of 250 front-line HCWs over the age of 20 was randomly allocated to receive either L. coryniformis K8 or a placebo daily. SARS-CoV-2 infection incidence was verified via PCR or antigen test. In those volunteers who were vaccinated during the intervention, serum levels of specific IgG were analyzed at the end of the study. The incidence of COVID-19 infection was very low [IR (SD) = 0.016 (0.011)], and no significant difference was found between the groups [IRR (95% CI): 1.008 (0.140-7.268), p = 0.994]. For immune response analysis, the total sample was divided according to the days between the first dose and the antibody analysis (cutoff points were set at ≤ 56, 57-80 and ≥ 81 days). The specific IgG level decreased over time (p > 0.001). However, in the subgroup of subjects for whom more than 81 days had passed since they received the first dose, the specific IgG levels were significantly higher in the those that took the L. coryniformis K8 [7.12 (0.21)] than in the control group [6.48 (0.19)] (P = 0.040). Interestingly, the subjects who started probiotic consumption before the first dose reported significantly fewer side effects (of any kind) at the 1st dose of the vaccine (OR: 0.524, p = 0.043), specifically less arm pain (OR: 0.467, p = 0.017). In conclusion, the administration of L. coryniformis K8 CECT 5711 to HCWs helps to extend the immune protection generated by the COVID-19 vaccine over time.
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Cesarean section (CS) disrupts the natural microbiota colonization process in infants, which might compromise immune system maturation, leading to a higher risk of infections. We evaluated the effect of the probiotic Limosilactobacillus (L.) fermentum CECT 5716 on the incidence of gastrointestinal and respiratory infections in the CS infant subgroups (n = 173) of three randomized clinical trials in which this probiotic strain was demonstrated to be safe and effective for preventing infections. Therefore, the data for the CS infants were extracted to obtain the incidence rate ratio (IRR) and 95% CI for gastrointestinal and respiratory infections for each study and were then combined to obtain a pooled IRR and 95% CI using the generic inverse variance method. There was a significant reduction of 73% in the incidence of gastrointestinal infections in CS infants receiving L. fermentum CECT 5716 compared with those receiving the control formula [n = 173, IRR: 0.27 (0.13, 0.53), p = 0.0002]. Regarding respiratory infections, although pooled results showed a reduction of 14% in the probiotic group, the difference was not statistically significant [n = 173, IRR (95% CI): 0.86 (0.67, 1.11), p = 0.25]. In conclusion, the administration of L. fermentum CECT 5716 to CS-born infants protects them from gastrointestinal infections by reducing the risk by up to 73% in this population.
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Mastitis is an inflammation of the mammary gland occurring in 3-33% of the breastfeeding mothers. The majority of mastitis cases have an infectious etiology. More than 75% of infectious mastitis are caused by Staphylococcus epidermidis and Staphylococcus aureus and involves breast milk microbiota alteration, which, may have an impact in lactating infant. The aim of this study was to analyze in rats during the suckling period and later in life the impact of a high and a low overload of Staphylococcus epidermidis, similarly as it occurs during the clinical and the subclinical mastitis, respectively. From days 2 to 21 of life, suckling rats were daily supplemented with low (Ls group) or high (Hs group) dose of S. epidermidis. Body weight and fecal humidity were periodically recorded. On days 21 and 42 of life, morphometry, hematological variables, intestinal gene expression, immunoglobulin (Ig) and cytokine profile and spleen cells' phenotype were measured. Although no differences were found in body weight, Ls and Hs groups showed higher body length and lower fecal humidity. Both doses induced small changes in lymphocytes subpopulations, reduced the plasma levels of Ig and delayed the Th1/Th2 balance causing a bias toward the Th2 response. No changes were found in cytokine concentration. The low dose affected the Tc cells intestinal homing pattern whereas the high dose had an impact on the hematological variables causing leukocytosis and lymphocytosis and also influenced the intestinal barrier maturation. In conclusion, both interventions with Staphylococcus epidermidis overload during suckling, affects the immune system development in short and long term.
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Background: The pathogenesis of autism spectrum disorder (ASD) is under investigation and one of the main alterations relates to the metabolic and inflammatory system dysfunctions. Indeed, based on a possible deficit of omega-3 fatty acids (FAs) of patients with ASD and looking for an anti-inflammatory effect, dietary supplements with omega-3 fatty acids have been proposed. We aimed to evaluate differences in plasma and erythrocyte FA profiles and plasma cytokines in patients with infantile ASD after supplementation with docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids or placebo and both compared at baseline with a reference healthy group. Methods: A double-blind, randomized placebo-controlled intervention with DHA/EPA for 6 months was carried out in 54 children between 2 and 6 years diagnosed with ASD. They were selected and randomly assigned into two groups: 19 children received 800 mg/day of DHA and 25 mg/day of EPA, or placebo. In addition, another reference group of 59 healthy children of the same age was included. Plasma lipids and cytokines, and FA profiles in plasma and erythrocytes were measured at baseline and after 6 months of treatment in ASD children, and at baseline in the reference group. Results: There were no differences in demographic, anthropometric characteristics, and omega-3 intake between the healthy reference group and the ASD children at baseline. Children with ASD showed the higher plasma percentages of palmitic acid and total saturated FA and lower total omega-6 polyunsaturated FA (PUFA) compared with healthy children. An increased level of DHA and reduced EPA level in erythrocytes were detected in the ASD group vs. the reference group. After 6 months of treatment, the ASD group that received DHA enriched product significantly increased the plasma and erythrocyte percentages of DHA, but no differences were observed in the clinical test scores and other parameters as plasma cytokines between the two groups of ASD related to the intervention. Conclusion: Spanish children with ASD exhibit an appropriate omega-3 FA status in plasma and erythrocytes. Neither a clinical improvement of ASD children nor a better anti-inflammatory or fatty acid state has been found after an intervention with DHA/EPA for 6 months. So, the prescription of n-3 LC-PUFA and other dietary supplements in ASD should be only indicated after a confirmed alteration of FA metabolism or omega-3 LC-PUFA deficiency evaluated by specific erythrocyte FA. Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT03620097].
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Elderly people are particularly vulnerable to COVID-19, with a high risk of developing severe disease and a reduced immune response to the COVID-19 vaccine. A randomized, placebo-controlled, double-blind trial to assess the effect of the consumption of the probiotic Loigolactobacillus coryniformis K8 CECT 5711 on the immune response generated by the COVID-19 vaccine in an elderly population was performed. Two hundred nursing home residents >60 yrs that had not COVID-19 were randomized to receive L. coryniformis K8 or a placebo daily for 3 months. All volunteers received a complete vaccination schedule of a mRNA vaccine, starting the intervention ten days after the first dose. Specific IgG and IgA antibody levels were analyzed 56 days after the end of the immunization process. No differences between the groups were observed in the antibody levels. During the intervention, 19 subjects had COVID-19 (11 receiving K8 vs. 8 receiving placebo, p = 0.457). Subgroup analysis in these patients showed that levels of IgG were significantly higher in those receiving K8 compared to placebo (p = 0.038). Among subjects >85 yrs that did not get COVID-19, administration of K8 tended to increase the IgA levels (p = 0.082). The administration of K8 may enhance the specific immune response against COVID-19 and may improve the COVID-19 vaccine-specific responses in elderly populations.
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Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Avaliação Geriátrica/métodos , Imunidade/imunologia , Lactobacillus/imunologia , Probióticos/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , Método Duplo-Cego , Feminino , Humanos , Masculino , SARS-CoV-2RESUMO
Our group tested the effects of Lactobacillus fermentum CECT5716 (LC40) and/or Bifidobacterium breve CECT7263 (BFM) in the prevention of gut dysbiosis, hypertension and endothelial dysfunction in a pharmacologically-induced model of systemic lupus erythematosus (SLE). We treated eight-week-old BALB/cByJRj mice without (Ctrl) or with the agonist of TLR-7 Imiquimod (IMQ) for 8 weeks. Concomitantly, LC40 (109 CFU/mL) and BFM (109 CFU/mL) were administered through oral gavage once a day. IMQ induced intestinal dysbiosis consisting of a decrease in the α-diversity measured with Chao-richness and numbers of species. LC40 and BFM did not restore these parameters. The three-dimensional principal component analysis of bacterial taxa in stool samples presented perfect clustering between Ctrl and IMQ groups. Clusters corresponding to LC40 and BFM were more akin to IMQ. BFM and LC40 were detected colonizing the gut microbiota of mice treated respectively. LC40 and BFM decreased plasma double-stranded DNA autoantibodies, and B cells in spleen, which were increased in the IMQ group. Also, LC40 and BFM treatments activated TLR9, reduced T cells activation, and Th17 polarization in mesenteric lymph nodes. Aortae from IMQ mice displayed a decreased endothelium-dependent vasodilator response to acetylcholine linked to pro-inflammatory and pro-oxidative status, which were normalized by both BFM and LC40. In conclusion, we demonstrate for the first time that the chronic treatment with LC40 or BFM prevented hypertension and endothelial dysfunction in a mouse lupus model induced by TLR-7 activation.
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Hipertensão/prevenção & controle , Lúpus Eritematoso Sistêmico/complicações , Probióticos/uso terapêutico , Receptor 7 Toll-Like/agonistas , Animais , Bifidobacterium breve , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Disbiose/microbiologia , Feminino , Microbioma Gastrointestinal , Imunidade , Limosilactobacillus fermentum , Lúpus Eritematoso Sistêmico/imunologia , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Ribossômico 16S , Espécies Reativas de OxigênioRESUMO
Reducing the incidence of gastrointestinal infections (GIs) that occur at early stages to mitigate hospitalizations and treatments with adverse effects is a promising strategy for providing well-being to infants and their families. This systematic review and meta-analysis explores whether the early administration of Limosilactobacillus fermentum CECT5716 might be effective as a preventive therapy for GIs. We reviewed the literature to identify randomized controlled trials (RCTs) investigating the effectiveness of milk formulas supplemented with L. fermentum CECT5716 administered to infants at early stages to reduce the incidence of GIs. The MEDLINE (via PubMed), Web of Science (WoS), and Cochrane Central Register of Controlled Trials (via CENTRAL) databases were searched up to 15 June 2021. GI data from the included studies were synthesized in a random-effects model. Three RCTs were finally selected including 435 infants. There was a significant reduction in the incidence rate of GIs for those receiving L. fermentum CECT5716 compared with those receiving placebo (IRR: 0.52, 95% CI: 0.36-0.74, p = 0.0004). Heterogeneity between studies was moderate (I2 = 54.5%). Based on the present systematic review and meta-analysis, the administration of L. fermentum CECT5716 at doses from 1 × 109 to 8.4 × 108 cfu/day in milk formulas may prevent GIs in infants up to 12 months old. Longer-term studies including a higher number of infants are needed to determine whether the use of this probiotic during the early stages of life is an efficient way to reduce the incidence of GIs.
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Aspergillus fumigatus is a human fungal pathogen that can cause devastating pulmonary infections, termed "aspergilloses," in individuals suffering immune imbalances or underlying lung conditions. As rapid adaptation to stress is crucial for the outcome of the host-pathogen interplay, here we investigated the role of the versatile posttranslational modification (PTM) persulfidation for both fungal virulence and antifungal host defense. We show that an A. fumigatus mutant with low persulfidation levels is more susceptible to host-mediated killing and displays reduced virulence in murine models of infection. Additionally, we found that a single nucleotide polymorphism (SNP) in the human gene encoding cystathionine γ-lyase (CTH) causes a reduction in cellular persulfidation and correlates with a predisposition of hematopoietic stem cell transplant recipients to invasive pulmonary aspergillosis (IPA), as correct levels of persulfidation are required for optimal antifungal activity of recipients' lung resident host cells. Importantly, the levels of host persulfidation determine the levels of fungal persulfidation, ultimately reflecting a host-pathogen functional correlation and highlighting a potential new therapeutic target for the treatment of aspergillosis.
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Antifúngicos/farmacologia , Aspergillus fumigatus/patogenicidade , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Sulfetos/metabolismo , Células A549 , Adulto , Animais , Aspergilose/epidemiologia , Aspergilose/genética , Aspergilose/microbiologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/enzimologia , Cistationina gama-Liase/genética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Incidência , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único/genética , Células THP-1 , Transplantados , Virulência/efeitos dos fármacos , Adulto JovemRESUMO
Obesity is one of the main features of metabolic syndrome, where a low-grade chronic inflammation and gut dysbiosis contribute to the development of the related metabolic dysfunctions. Different probiotics have demonstrated beneficial effects on this condition, increasing the interest in the development of probiotic treatments. Lactobacillus fermentum CECT5716 has shown anti-inflammatory effects and capacity to modulate microbiota composition in different experimental models. In this study, L. fermentum CECT5716 was evaluated in a model of high fat diet-induced obesity in mice. It exerts anti-obesity effects, associated with its anti-inflammatory properties and amelioration of endothelial dysfunction and gut dysbiosis. The probiotic restores Akkermansia sp. abundance and reduced Erysipelotrichi class and Clostridium spp presence as well as increased Bacteroides proportion. In conclusion, this probiotic represents a very interesting approach. Our findings describe, for the first time, the ability of this probiotic to ameliorate experimental obesity through microbiome modulation, affecting different bacteria that have been reported to play a key role in the pathogenesis of obesity. Therefore, this suggests a potential use of L. fermentum CECT5716 in clinical practice, also taking into account that probiotic treatments have demonstrated to be relatively safe and well tolerated.
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Disbiose/terapia , Microbioma Gastrointestinal , Limosilactobacillus fermentum , Obesidade/terapia , Probióticos/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Disbiose/etiologia , Disbiose/metabolismo , Limosilactobacillus fermentum/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/metabolismo , Probióticos/metabolismoRESUMO
The alarming increase of antibiotic-resistant bacteria, causing conventional treatments of bacterial infections to become increasingly inefficient, is one of the biggest threats to global health. Here, we have developed probiotic cellulose, an antibiotic-free biomaterial for the treatment of severe skin infections and chronic wounds. This composite biomaterial was in-depth characterized by Gram stain, scanning electron microscopy (SEM) and confocal fluorescence microscopy. Results demonstrated that probiotic cellulose consists of dense films of cellulose nanofibers, free of cellulose-producing bacteria, completely invaded by live probiotics (Lactobacillus fermentum or Lactobacillus gasseri). Viability assays, including time evolution of pH and reducing capacity against electrochromic polyoxometalate, confirmed that probiotics within the cellulose matrix are not only alive but also metabolically active, a key point for the use of probiotic cellulose as an antibiotic-free antibacterial biomaterial. Antibacterial assays in pathogen-favorable media, a real-life infection scenario, demonstrated that probiotic cellulose strongly reduces the viability of Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA), the most active pathogens in severe skin infections and chronic wounds. Likewise, probiotic cellulose was also found to be effective to inhibit the proliferation of methicillin-resistant SA (MRSA). The combination of the properties of bacterial cellulose as wound dressing biomaterial and the antibacterial activity of probiotics makes probiotic cellulose an alternative to antibiotics for the treatment of topical infections, including severe and hard-to-heal chronic wounds. In addition, probiotic cellulose was obtained by a one-pot synthetic approach under mild conditions, not requiring the long and expensive chemical treatments to purify the genuine bacterial cellulose.
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Staphylococcus aureus Resistente à Meticilina , Probióticos , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , CeluloseRESUMO
Hydroxytyrosol (HT) from olives and polyphenols from almond skin (ASPs) possess cardioprotective properties. This pilot study evaluates the effect of supplementation with a combination of olive fruit and almond skin extracts on low-density lipoprotein (LDL) cholesterol oxidation, lipid homeostasis, and inflammatory parameters in adults with moderate hypercholesterolemia. A randomized, parallel, double-blind, placebo-controlled pilot study of 8 weeks was performed. The extract group (EG) received the supplement with 7.5 mg HT +210 mg ASPs, and the control group (CG) received a placebo composed of maltodextrin. Oxidized LDL (oxLDL) levels and the oxLDL/LDL ratio were lower in the EG than in the CG after 8 weeks of treatment (18.76 ± 3.91 vs. 10.34 ± 4.22, P < .001 and 0.151 ± 0.025 vs. 0.08 ± 0.023, P < .001, respectively). Interleukin-1ß levels were significantly higher in the CG than in the EG at week 4 (P = .004), IL-6 was significantly higher in the CG than in the EG at week 4 (P = .049), and IL-10 was significantly increased at week 4 in both groups (P = .002 for CG and P = .001 for EG). In conclusion, daily consumption of a combination of an olive fruit extract and an almond skin extract for 8 weeks seems to protect LDL from oxidation and to prevent inflammatory status in moderately hypercholesterolemic subjects.
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Olea , Prunus dulcis , Adulto , Método Duplo-Cego , Frutas , Humanos , Inflamação , Lipoproteínas LDL , Estresse Oxidativo , Projetos Piloto , Extratos VegetaisRESUMO
PURPOSE: Probiotics have been shown to exert beneficial effects in IBD although their exact mechanisms are not completely understood. The aim of the present study was to assess the intestinal anti-inflammatory activity of different probiotics (Lactobacillus fermentum CECT5716, Lactobacillus salivarius CECT5713, Escherichia coli Nissle 1917, Saccharomyces boulardii CNCMI-745 in the dinitrobenzene sulfonic acid (DNBS) model of mouse colitis and correlate it with the modifications of the gut microbiota and the immune response, focusing on miRNA expression. METHODS: The probiotics were daily administered orally for 25 days. On day 19 colitis was induced by rectal installation of DNBS. At the end of the treatment, mice were sacrificed and the colonic damage was assessed biochemically by analysing the expression of different markers involved in the immune response, including miRNAs; and the colonic microbiota by pyrosequencing. Probiotics properties were also evaluated in vitro in different immune cell types (CMT-93 intestinal epithelial cells and bone marrow-derived macrophages), where the expression of different mRNAs and miRNAs was examined. RESULTS: All the probiotics displayed intestinal anti-inflammatory effects but slightly different, especially regarding miRNAs expression. Likewise, the probiotics ameliorated the colitis-associated dysbiosis, although showing differences in the main bacterial groups affected. CONCLUSION: Among the probiotics assayed, Lactobacillus fermentum CECT5716 and Escherichia coli Nissle 1917 appear to present the best intestinal anti-inflammatory effects, being the latter one of the few probiotics with reputed efficacy in human IBD. Therefore, Lactobacillus fermentum CECT5716 could be considered as a complementary nutritional strategy for IBD treatment.
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Colite , Microbioma Gastrointestinal , MicroRNAs , Probióticos , Animais , Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Colite/terapia , Dinitrobenzenos/uso terapêutico , Camundongos , MicroRNAs/genética , Ácidos Sulfônicos/uso terapêuticoRESUMO
There is an urgent need to develop novel antifungals to tackle the threat fungal pathogens pose to human health. Here, we have performed a comprehensive characterization and validation of the promising target methionine synthase (MetH). We show that in Aspergillus fumigatus the absence of this enzymatic activity triggers a metabolic imbalance that causes a reduction in intracellular ATP, which prevents fungal growth even in the presence of methionine. Interestingly, growth can be recovered in the presence of certain metabolites, which shows that metH is a conditionally essential gene and consequently should be targeted in established infections for a more comprehensive validation. Accordingly, we have validated the use of the tetOFF genetic model in fungal research and improved its performance in vivo to achieve initial validation of targets in models of established infection. We show that repression of metH in growing hyphae halts growth in vitro, which translates into a beneficial effect when targeting established infections using this model in vivo Finally, a structure-based virtual screening of methionine synthases reveals key differences between the human and fungal structures and unravels features in the fungal enzyme that can guide the design of novel specific inhibitors. Therefore, methionine synthase is a valuable target for the development of new antifungals.IMPORTANCE Fungal pathogens are responsible for millions of life-threatening infections on an annual basis worldwide. The current repertoire of antifungal drugs is very limited and, worryingly, resistance has emerged and already become a serious threat to our capacity to treat fungal diseases. The first step to develop new drugs is often to identify molecular targets in the pathogen whose inhibition during infection can prevent its growth. However, the current models are not suitable to validate targets in established infections. Here, we have characterized the promising antifungal target methionine synthase in great detail, using the prominent fungal pathogen Aspergillus fumigatus as a model. We have uncovered the underlying reason for its essentiality and confirmed its druggability. Furthermore, we have optimized the use of a genetic system to show a beneficial effect of targeting methionine synthase in established infections. Therefore, we believe that antifungal drugs to target methionine synthase should be pursued and additionally, we provide a model that permits gaining information about the validity of antifungal targets in established infections.
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5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/antagonistas & inibidores , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/genética , Animais , Modelos Animais de Doenças , Genes Essenciais , Aspergilose Pulmonar Invasiva , Larva/microbiologia , Leucopenia , Masculino , Camundongos , Mariposas/microbiologia , Virulência/genéticaRESUMO
The aim of this study was to evaluate the effect of two doses of d-chiro-inositol (DCI) in combination with Myo-inositol (MYO) on the oocyte quality (OQ) of women with polycystic ovarian syndrome (PCOS) undergoing intracytoplasmic sperm injection (ICSI). Methods: This was a controlled, randomized, double-blind, parallel group study on 172 oocytes from 11 women. The study compared the effect of two MYO-DCI formulations given over 12 weeks on OQ. Five women received 550 mg of MYO + 300 mg of DCI daily (high DCI content group), while 6 women were given a daily dose of 550 mg of MYO with the only 27.6 mg of DCI (low DCI content group). Results: According to a multivariate analysis using linear mixed effect models, high doses of DCI have a positive influence on the quality of the cytoplasm of the oocyte (ß = 1.631, χ2 = 7.347, d.f. = 1, p = .00672). Zona pellucida, plasma membrane, cytoplasm, and sperm reception have also been improved with any combination of MYO/DCI by decreasing testosterone or improving insulin sensitivity, regardless of age and body mass index. Conclusion: The combination of MYO with high doses of DCI improved oocyte cytoplasm quality in women with PCOS undergoing ICSI.
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Infertilidade Feminina/tratamento farmacológico , Inositol/administração & dosagem , Oócitos/efeitos dos fármacos , Síndrome do Ovário Policístico/complicações , Complexo Vitamínico B/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Humanos , Infertilidade Feminina/etiologia , Injeções de Esperma IntracitoplásmicasRESUMO
Pathogen-pathogen interactions in polymicrobial infections are known to directly impact, often to worsen, disease outcomes. For example, co-infection with Pseudomonas aeruginosa and Aspergillus fumigatus, respectively the most common bacterial and fungal pathogens isolated from cystic fibrosis (CF) airways, leads to a worsened prognosis. Recent studies of in vitro microbial cross-talk demonstrated that P. aeruginosa-derived volatile sulfur compounds (VSCs) can promote A. fumigatus growth in vitro. However, the mechanistic basis of such cross-talk and its physiological relevance during co-infection remains unknown. In this study we combine genetic approaches and GC-MS-mediated volatile analysis to show that A. fumigatus assimilates VSCs via cysteine (CysB)- or homocysteine (CysD)-synthase. This process is essential for utilization of VSCs as sulfur sources, since P. aeruginosa-derived VSCs trigger growth of A. fumigatus wild-type, but not of a ΔcysBΔcysD mutant, on sulfur-limiting media. P. aeruginosa produces VSCs when infecting Galleria mellonella and co-infection with A. fumigatus in this model results in a synergistic increase in mortality and of fungal and bacterial burdens. Interestingly, the increment in mortality is much greater with the A. fumigatus wild-type than with the ΔcysBΔcysD mutant. Therefore, A. fumigatus' ability to assimilate P. aeruginosa derived VSCs significantly triggers a synergistic association that increases the pathobiology of infection. Finally, we show that P. aeruginosa can promote fungal growth when growing on substrates that resemble the lung environment, which suggests that this volatile based synergism is likely to occur during co-infection of the human respiratory airways.
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Previous studies have reported that probiotics may improve clinical and inflammatory parameters in patients with obesity and metabolic syndrome (MetS). Lactobacillus (L.) reuteri V3401 has shown promising results on the components of MetS in animal studies. We aimed to evaluate the effects of L. reuteri V3401 together with healthy lifestyle recommendations on adult patients with MetS. METHODS: We carried out a randomized, crossover, placebo-controlled, single-center trial in which we included 53 adult patients newly diagnosed with MetS. Patients were block randomly allocated by body mass index (BMI) and sex to receive a capsule containing either the probiotic L. reuteri V3401 (5 × 109 colony-forming units) or a placebo once daily for 12 weeks. Anthropometric variables, biochemical and inflammatory biomarkers, as well as the gastrointestinal microbiome composition were determined. RESULTS: There were no differences between groups in the clinical characteristics of MetS. However, we found that interleukin-6 (IL-6) and soluble vascular cell adhesion molecule 1 (sVCAM-1) diminished by effect of the treatment with L. reuteri V3401. Analysis of the gastrointestinal microbiome revealed a rise in the proportion of Verrucomicrobia. CONCLUSIONS: Consumption of L. reuteri V3401 improved selected inflammatory parameters and modified the gastrointestinal microbiome. Further studies are needed to ascertain additional beneficial effects of other probiotic strains in MetS as well as the mechanisms by which such effects are exerted.
Assuntos
Microbioma Gastrointestinal , Inflamação/metabolismo , Limosilactobacillus reuteri , Síndrome Metabólica/sangue , Síndrome Metabólica/terapia , Adulto , Biomarcadores/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Inflamação/sangue , Masculino , Síndrome Metabólica/metabolismo , ProbióticosRESUMO
The purpose of this study was to evaluate the effect of two doses of D-chiro-inositol (DCI) in combination with Myo-inositol (MYO) in women with PCOS undergoing ICSI. This was a multicenter controlled, randomized, double-blind parallel group study with two MYO-DCI formulations for 12 weeks. The study group (SG) was administered 550 mg of MYO + 150 mg of DCI twice daily; the control group (CG) was administered 550 mg of MYO + 13.8 mg of DCI twice daily. The participants comprised 60 women with PCOS undergoing ICSI. At baseline, no differences were found between the two groups regarding age, BMI, HOMA-IR or testosterone levels. The pregnancy and live birth rates were significantly higher in the SG than in the CG (65.5 vs. 25.9 and 55.2 vs. 14.8, respectively) [risk ratio (RR) = 0.4; 95%CI (0.2, 0.79); p = .003 and RR = 0.27; 95%CI (0.10, 0.70); p = .002 respectively]. The risk of ovarian hyperstimulation syndrome (OHSS) was lower in the SG (3.44 vs. 18.5%, p = .07). The combination of MYO-DCI at high doses of DCI improves the pregnancy rates and reduces the risk of OHSS in women with PCOS undergoing ICSI.