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1.
Development ; 148(5)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33593820

RESUMO

Microbial factors influence homeostatic and oncogenic growth in the intestinal epithelium. However, we know little about immediate effects of commensal bacteria on stem cell division programs. In this study, we examined the effects of commensal Lactobacillus species on homeostatic and tumorigenic stem cell proliferation in the female Drosophila intestine. We identified Lactobacillus brevis as a potent stimulator of stem cell divisions. In a wild-type midgut, L. brevis activates growth regulatory pathways that drive stem cell divisions. In a Notch-deficient background, L. brevis-mediated proliferation causes rapid expansion of mutant progenitors, leading to accumulation of large, multi-layered tumors throughout the midgut. Mechanistically, we showed that L. brevis disrupts expression and subcellular distribution of progenitor cell integrins, supporting symmetric divisions that expand intestinal stem cell populations. Collectively, our data emphasize the impact of commensal microbes on division and maintenance of the intestinal progenitor compartment.


Assuntos
Adesão Celular , Proliferação de Células , Drosophila/metabolismo , Intestinos/citologia , Lactobacillus brevis/fisiologia , Células-Tronco/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Antibacterianos/farmacologia , Diferenciação Celular , Linhagem da Célula , Transformação Celular Neoplásica/efeitos dos fármacos , Regulação para Baixo , Drosophila/microbiologia , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Integrinas/metabolismo , Intestinos/microbiologia , Lactobacillus brevis/efeitos dos fármacos , Receptores Notch/deficiência , Receptores Notch/genética , Células-Tronco/citologia , Células-Tronco/microbiologia
2.
Microb Cell Fact ; 19(1): 106, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430020

RESUMO

BACKGROUND: We evaluated the functional capacity of plantaricin-producing Lactobacillus plantarum SF9C and S-layer-carrying Lactobacillus brevis SF9B to withstand gastrointestinal transit and to compete among the gut microbiota in vivo. Considering the probiotic potential of Lb. brevis SF9B, this study aims to investigate the antibacterial activity of Lb. plantarum SF9C and their potential for in vivo colonisation in rats, which could be the basis for the investigation of their synergistic functionality. RESULTS: A plantaricin-encoding cluster was identified in Lb. plantarum SF9C, a strain which efficiently inhibited the growth of Listeria monocytogenes ATCC® 19111™ and Staphylococcus aureus 3048. Homology-based three-dimensional (3D) structures of SF9C plantaricins PlnJK and PlnEF were predicted using SWISS-MODEL workspace and the helical wheel representations of the plantaricin peptide helices were generated by HELIQUEST. Contrary to the plantaricin-producing SF9C strain, the S-layer-carrying SF9B strain excluded Escherichia coli 3014 and Salmonella enterica serovar Typhimurium FP1 from the adhesion to Caco-2 cells. Finally, PCR-DGGE analysis of the V2-V3 regions of the 16S rRNA gene confirmed the transit of the two selected lactobacilli through the gastrointestinal tract (GIT). Microbiome profiling via the Illumina MiSeq platform revealed the prevalence of Lactobacillus spp. in the gut microbiota of the Lactobacillus-treated rats, even on the 10th day after the Lactobacillus application, compared to the microbiota of the healthy and AlCl3-exposed rats before Lactobacillus treatment. CONCLUSION: The combined application of Lb. plantarum SF9C and Lb. brevis SF9B was able to influence the intestinal microbiota composition in rats, which was reflected in the increased abundance of Lactobacillus genus, but also in the altered abundances of other bacterial genera, either in the model of healthy or aberrant gut microbiota of rats. The antibacterial activity and capacity to withstand in GIT conditions contributed to the functional aspects of SF9C and SF9B strains that could be incorporated in the probiotic-containing functional foods with a possibility to positively modulate the gut microbiota composition.


Assuntos
Antibiose , Trânsito Gastrointestinal , Lactobacillus brevis/fisiologia , Lactobacillus plantarum/fisiologia , Probióticos/administração & dosagem , Animais , Bacteriocinas , Células CACO-2 , Microbioma Gastrointestinal , Humanos , Lactobacillus brevis/genética , Lactobacillus plantarum/genética , Masculino , Glicoproteínas de Membrana/genética , Ratos , Salmonella typhimurium , Staphylococcus aureus
3.
Nutrients ; 12(3)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110872

RESUMO

Our previous study reported that lactic acid bacteria (L. brevis OPK-3) isolated from kimchi ameliorated intracellular lipid accumulation in 3T3-L1 adipocyte. The current study explored potential roles of L. brevis OPK-3 (KLAB) on preventing body weight gain and its effect on the inflammatory response of adipose tissue. Male C57BL/6 mice (n = 10) were divided into four groups: normal diet with distilled water (NDC), high-fat diet with distilled water (HDC), high-fat diet with L-ornithine (OTC) or high-fat diet with KLAB. The KLAB supplement resulted in significantly lower body weight, lower epididymal fat tissue mass, and lower serum and hepatic TG levels than the HDC. KLAB supplementation improved serum cytokines, and real-time polymerase chain reaction (PCR) analysis showed significantly lower inflammatory cytokine mRNA levels in epididymal adipose tissue. These results suggest that the administration of KLAB inhibits the induction of inflammation in adipose tissue along with the inhibition of weight gain. Therefore, this study demonstrates the therapeutic and beneficial value of this strain produced during the fermentation of kimchi.


Assuntos
Adipogenia/genética , Tecido Adiposo/patologia , Dieta Hiperlipídica , Alimentos e Bebidas Fermentados/microbiologia , Regulação da Expressão Gênica , Inflamação/genética , Lactobacillus brevis/fisiologia , Obesidade/genética , Animais , Glicemia/metabolismo , Composição Corporal , Peso Corporal , Análise por Conglomerados , Citocinas/sangue , Perfilação da Expressão Gênica , Mediadores da Inflamação/sangue , Lipídeos/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/sangue , Tamanho do Órgão , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Appl Microbiol Biotechnol ; 104(9): 4071-4080, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32179950

RESUMO

This study aimed to model the inactivation of Lactobacillus brevis DSM 6235 while retaining the viability of yeasts during washing brewer's yeast with phosphoric acid and chlorine dioxide. The independent variables in the acid washing were pH (1-3) and temperature (1-9 °C), whereas in the washing with chlorine dioxide, concentration (10-90 mg/L) and temperature (5-25 °C) were assessed. The predictive models obtained for the four response variables γLA, γCl (decimal reduction of L. brevis DSM 6235), Vf/V0LA, and Vf/V0Cl (brewer's yeast viability ratio) were found to have R2 > 0.80 and values of Fcalc > Freference. Then, the models were considered predictive and statistically significant (p < 0.10). Our results indicated that phosphoric acid and chlorine dioxide washing resulted in up to 7 and 6.4 (log CFU/mL) decimal reductions of L. brevis DSM 6235, respectively. On the other hand, the viability of the brewer's yeast ranged from 22.3 to 99.4%. L. brevis DSM 6235 inactivation was significantly influenced by parameters pH(Q) and T°C(Q) when phosphoric acid was applied, and by parameters mg/L(L), mg/L(Q), T°C(Q), and mg/L × T°C when ClO2 was applied. The validation of the models resulted in bias (γLA, 0.93/Vf/V0LA, 0.99 - γCl, 1.0/Vf/V0Cl, 0.99) and accuracy values (γLA, 1.12/Vf/V0LA, 1.01 - γCl, 1.08/Vf/V0Cl, 1.03). The results of this study indicate that it might be possible to decontaminate brewer's yeast through acid and chlorine dioxide washing while keeping its viability. This procedure will result in the reduction of costs and the lower generation of brewer's waste.


Assuntos
Compostos Clorados/farmacologia , Fermentação , Lactobacillus brevis/fisiologia , Viabilidade Microbiana , Óxidos/farmacologia , Ácidos Fosfóricos/farmacologia , Saccharomyces cerevisiae/fisiologia , Cerveja/microbiologia , Concentração de Íons de Hidrogênio , Lactobacillus brevis/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Temperatura
5.
Probiotics Antimicrob Proteins ; 12(4): 1484-1491, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32077013

RESUMO

Inorganic arsenic [iAs, As(III) + As(V)] is considered a human carcinogen. Recent studies show that it has also toxic effects on the intestinal epithelium which might partly explain its systemic toxicity. The aim of this study is to evaluate the protective role of lactic acid bacteria (LAB) against the toxic effects of iAs on the intestinal epithelium. For this purpose, the human colonic cells Caco-2 were exposed to As(III) in the presence of various LAB strains or their conditioned medium. Results showed that some strains and their conditioned media partially revert the oxidative stress, the production of pro-inflammatory cytokines, the alterations of the distribution of tight junction proteins, and the cell permeability increases caused by As(III). These results show that both soluble factors secreted or resulting from LAB metabolism and cell-cell interactions are possibly involved in the beneficial effects. Therefore, some LAB strains have potential as protective agents against iAs intestinal barrier disruption.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Arsênio/toxicidade , Lactobacillus acidophilus/química , Lactobacillus brevis/química , Lactobacillus casei/química , Probióticos/farmacologia , Anti-Inflamatórios/química , Antioxidantes/química , Células CACO-2 , Permeabilidade da Membrana Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Corantes Fluorescentes/análise , Corantes Fluorescentes/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Isoquinolinas/análise , Isoquinolinas/metabolismo , Lactobacillus acidophilus/fisiologia , Lactobacillus brevis/fisiologia , Lactobacillus casei/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Probióticos/química , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
6.
Sci Rep ; 9(1): 16323, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704943

RESUMO

Metabolic and neuroactive metabolite production represents one of the mechanisms through which the gut microbiota can impact health. One such metabolite, gamma-aminobutyric acid (GABA), can modulate glucose homeostasis and alter behavioural patterns in the host. We previously demonstrated that oral administration of GABA-producing Lactobacillus brevis DPC6108 has the potential to increase levels of circulating insulin in healthy rats. Therefore, the objective of this study was to assess the efficacy of endogenous microbial GABA production in improving metabolic and behavioural outcomes in a mouse model of metabolic dysfunction. Diet-induced obese and metabolically dysfunctional mice received one of two GABA-producing strains, L. brevis DPC6108 or L. brevis DSM32386, daily for 12 weeks. After 8 and 10 weeks of intervention, the behavioural and metabolic profiles of the mice were respectively assessed. Intervention with both L. brevis strains attenuated several abnormalities associated with metabolic dysfunction, causing a reduction in the accumulation of mesenteric adipose tissue, increased insulin secretion following glucose challenge, improved plasma cholesterol clearance and reduced despair-like behaviour and basal corticosterone production during the forced swim test. Taken together, this exploratory dataset indicates that intervention with GABA-producing lactobacilli has the potential to improve metabolic and depressive- like behavioural abnormalities associated with metabolic syndrome in mice.


Assuntos
Comportamento Animal , Depressão/complicações , Lactobacillus brevis/metabolismo , Síndrome Metabólica/microbiologia , Síndrome Metabólica/psicologia , Ácido gama-Aminobutírico/biossíntese , Tecido Adiposo/patologia , Animais , Peso Corporal , Colesterol/metabolismo , Corticosterona/metabolismo , Depressão/metabolismo , Depressão/fisiopatologia , Modelos Animais de Doenças , Trânsito Gastrointestinal , Glucose/metabolismo , Resistência à Insulina , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Lactobacillus brevis/fisiologia , Aprendizagem em Labirinto , Síndrome Metabólica/complicações , Síndrome Metabólica/fisiopatologia , Metabolômica , Camundongos
7.
J Microbiol Biotechnol ; 29(12): 1894-1903, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31581386

RESUMO

The purpose of this study was to determine the probiotic properties of Lactobacillus brevis KCCM 12203P isolated from the Korean traditional food kimchi and to evaluate the antioxidative activity and immune-stimulating potential of its heat-killed cells to improve their bio-functional activities. Lactobacillus rhamnosus GG, which is a representative commercial probiotic, was used as a comparative sample. Regarding probiotic properties, L. brevis KCCM 12203P was resistant to 0.3% pepsin with a pH of 2.5 for 3 h and 0.3% oxgall solution for 24 h, having approximately a 99% survival rate. It also showed strong adhesion activity (6.84%) onto HT-29 cells and did not produce ß-glucuronidase but produced high quantities of leucine arylamidase, valine arylamidase, ß-galactosidase, and N-acetyl-ß- glucosaminidase. For antioxidant activity, it appeared that viable cells had higher radical scavenging activity in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, while in the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, heat-killed cells had higher antioxidant activity. Additionally, L. brevis KCCM 12203P showed higher lipid oxidation inhibition ability than L. rhamnosus GG; however, there was no significant difference (p < 0.05) between heat-killed cells and control cells. Furthermore, heat-killed L. brevis KCCM 12203P activated RAW 264.7 macrophage cells without cytotoxicity at a concentration lower than 108 CFU/ml and promoted higher gene expression levels of inducible nitric oxide synthase, interleukin-1ß, and interleukin-6 than L. rhamnosus GG. These results suggest that novel L. brevis KCCM 12203P could be used as a probiotic or applied to functional food processing and pharmaceutical fields for immunocompromised people.


Assuntos
Antioxidantes/metabolismo , Alimentos e Bebidas Fermentados/microbiologia , Imunização , Lactobacillus brevis/isolamento & purificação , Lactobacillus brevis/fisiologia , Probióticos/farmacologia , Animais , Aderência Bacteriana , Sobrevivência Celular/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Manipulação de Alimentos , Sequestradores de Radicais Livres , Expressão Gênica , Células HT29 , Temperatura Alta , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lactobacillus brevis/classificação , Lactobacillus brevis/genética , Camundongos , Óxido Nítrico Sintase/metabolismo , Filogenia , Células RAW 264.7
8.
Nutrients ; 11(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234292

RESUMO

There is growing interest in bioactive substances from marine organisms for their potential use against diverse human diseases. Osteoporosis is a skeletal disorder associated with bone loss primarily occurring through enhanced osteoclast differentiation and resorption. Recently, we reported the anti-osteoclastogenic activity of fermented Pacific oyster (Crassostrea gigas) extract (FO) in vitro. The present study focused on investigating the anti-osteoporotic efficacy of FO in bone loss prevention in an experimental animal model of osteoporosis and elucidating the mechanism underlying its effects. Oral administration of FO significantly decreased ovariectomy-induced osteoclast formation and prevented bone loss, with reduced serum levels of bone turnover biomarkers including osteocalcin and C-terminal telopeptide fragment of type I collagen C-terminus (CTX). FO significantly suppressed receptor activator of nuclear factor-κB ligand (RANKL)-induced differentiation of bone marrow-derived macrophages (BMMs) into osteoclasts and attenuated the induction of osteoclast-specific genes required for osteoclastogenesis and bone resorption. Furthermore, FO inhibited RANKL-mediated IκBα and p65 phosphorylation in BMMs. Taken together, these results demonstrate that FO effectively suppresses osteoclastogenesis in vivo and in vitro, and that FO can be considered as a potential therapeutic option for the treatment of osteoporosis and osteoclast-mediated skeletal diseases.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Crassostrea/microbiologia , Fermentação , Lactobacillus brevis/fisiologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/prevenção & controle , Ovariectomia , Alimentos Marinhos/microbiologia , Tíbia/efeitos dos fármacos , Actinas/metabolismo , Animais , Conservadores da Densidade Óssea/isolamento & purificação , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Transdução de Sinais , Tíbia/metabolismo , Tíbia/patologia , Tíbia/fisiopatologia
9.
Anticancer Res ; 39(4): 1935-1942, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30952736

RESUMO

BACKGROUND: Oropharyngeal mucositis occurs in virtually all patients with head and neck cancer receiving radiochemotherapy. The manipulation of the oral cavity microbiota represents an intriguing and challenging target. PATIENTS AND METHODS: A total of 75 patients were enrolled to receive Lactobacillus brevis CD2 lozenges or oral care regimen with sodium bicarbonate mouthwashes. The primary endpoint was the incidence of grade 3 or 4 oropharyngeal mucositis during radiotherapy treatment. RESULTS: There was no statistical difference in the incidence of grade 3-4 oropharyngeal mucositis between the intervention and control groups (40.6% vs. 41.6% respectively, p=0.974). The incidence of pain, dysphagia, body weight loss and quality of life were not different between the experimental and standard arm. CONCLUSION: Our study was not able to demonstrate the efficacy of L. brevis CD2 lozenges in preventing radiation-induced mucositis in patients with head and neck cancer. Although modulating homeostasis of the salivary microbiota in the oral cavity seems attractive, it clearly needs further study.


Assuntos
Quimiorradioterapia/efeitos adversos , Neoplasias de Cabeça e Pescoço/terapia , Lactobacillus brevis/fisiologia , Boca/microbiologia , Antissépticos Bucais/administração & dosagem , Probióticos/administração & dosagem , Bicarbonato de Sódio/administração & dosagem , Estomatite/prevenção & controle , Administração Oral , Adulto , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Antissépticos Bucais/efeitos adversos , Estudos Prospectivos , Saliva/microbiologia , Bicarbonato de Sódio/efeitos adversos , Estomatite/diagnóstico , Estomatite/microbiologia , Fatores de Tempo , Resultado do Tratamento
10.
Biosci Biotechnol Biochem ; 83(8): 1523-1529, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30822234

RESUMO

Some Lactobacillus brevis strains were found to aggregate upon the addition of glucose, which resulted in glucose fermentation and pH decrease. Surface layer proteins (Slp) that represented the outermost layer of the bacteria decreased under these low pH conditions, probably because of the partial detachment of Slp from the cell surface triggered by the acidic environment. Similar observations of decreased Slp and aggregation were observed under the culture conditions, confirming that L. brevis aggregation was due to the partial Slp detachment under the acidic conditions of glucose fermentation. Such Slp detachment might affect the electrostatic nature of L. brevis cells by initiating the formation of irregular charge across the L. brevis cell surface, thereby leading to aggregation. These observations would be useful for elucidating the aggregation mechanism of lactic acid bacteria, which was considered to be involved in the probiotic effect of the bacteria.


Assuntos
Fermentação , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus brevis/fisiologia , Lactobacillus brevis/metabolismo , Probióticos , Eletricidade Estática
11.
BMC Complement Altern Med ; 19(1): 37, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30709347

RESUMO

BACKGROUND: Listeria monocytogenes is an opportunistic foodborne pathogen that causes human Listeriosis and high mortality particularly in immunocompromised individuals. Pregnant women are more prone to L. monocytogenes infection resulting in abortions. In the present study, antilisterial activity of Lactobacillus brevis (LB) MF179529, a probiotic bacterial strain, was investigated in a murine model. METHODS: Initially a pilot study was conducted to determine the dose of L. monocytogenes required to cause symptomatic listeriosis. In the main trial, mice were divided into 4 groups. Group I was kept as negative control, group II was exposed to L. monocytogenes and maintained as positive control. Group III was fed with L. brevis only, while group IV received L. brevis for 3 days prior to L. monocytogenes infection. A volume of 200 µl of L. monocytogenes ATCC 19115 and L. brevis MF179529 bacterial suspension corresponding to cell density of 109CFU/ml were given to respective groups by intragastric route. Progress of infection was monitored for 7 days including general health scoring, listeria dispersion in organs, bacterial load in intestine and blood biochemistry were recorded on 3rd, 5th and 7th days post infection (dpi). RESULTS: Clinical listeriosis was induced by 109CFU/ml of L. monocytogenes ATCC 19115 in mice. Animals of group IV displayed minor signs of infection. L. brevis supplementation resulted in significant reduction in dispersion and propagation of L. monocytogenes in liver, spleen and intestine. L. brevis MF179529 consumption led to a significant elevation of number of lactic acid bacteria and reduction of total plate count, anaerobic count and coliform population in intestine. Moreover, total leukocyte and neutrophil counts of treated animals were similar to the negative control while positive control group displayed higher number. Safety evaluation of L. brevis was performed by monitoring general health, hematological and serological parameters of L. brevis fed and negative control group (group III and I). No significant difference in feed intake, body temperature, body weight and blood picture could be detected in L. brevis supplemented and control groups. CONCLUSION: Our results indicate ameliorative role of L. brevis in L. monocytogenes infection and suggest that L. brevis could be used for prophylactic measure.


Assuntos
Antibacterianos/farmacologia , Lactobacillus brevis/fisiologia , Listeria monocytogenes/efeitos dos fármacos , Probióticos/farmacologia , Animais , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/métodos , Temperatura Corporal , Bovinos , Modelos Animais de Doenças , Feminino , Listeria monocytogenes/patogenicidade , Listeriose/tratamento farmacológico , Listeriose/microbiologia , Camundongos , Probióticos/uso terapêutico
12.
J Appl Microbiol ; 126(4): 1221-1232, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30597726

RESUMO

AIMS: This study aimed at isolating a probiotic strain from a collection of lactic acid bacteria (LAB) with the high antioxidant property and confirms its potential in d-gal-induced oxidative stress (OS) murine model. METHODS AND RESULTS: The in vitro antioxidant ability of 16 LAB strains was determined in the cell-free supernatant of 3- to 5-day-old culture, intact cells and cell lysates using three different methods for determining the reactive oxygen species scavenging activity and inhibition of lipid peroxidation. The strain, An28, presented the best antioxidant activity and was identified as Lactobacillus brevis MG000874 on the basis of 16 sRNA gene sequencing. The antioxidant potential of L. brevis MG000874 was confirmed in an OS murine model. Albino mice were exposed to d-galactose at a dose of 150 mg kg-1 BW and fed with L. brevis MG000874 (0·2 ml of 1010 CFU per ml cell suspension per animal per day). Antioxidant enzymes were quantified spectrophotometrically in the liver, kidney and serum. Subcutaneous administration of d-gal resulted in decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) and increase in glutathione-S-transferase (GST) levels in animals. The L. brevis MG000874-treated animals displayed improvement in SOD, CAT and GST in all tissues and GSH in the liver and serum. The safety assessment of L. brevis MG000874 was performed by comparing liver and renal function tests. None of the selected indicators was significantly different from the negative control group. CONCLUSIONS: The antioxidant potential of 16 strains was noticed to be strain specific and in vivo performance of L. brevis MG000874 was found satisfactory in a d-gal murine model. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus brevis MG000874 was identified for its admirable antioxidant property. This strain or/and its metabolites could be further investigated for possible applications in humans and veterinary fields.


Assuntos
Antioxidantes/fisiologia , Lactobacillus brevis/fisiologia , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Modelos Animais de Doenças , Galactose/efeitos adversos , Lactobacillus brevis/classificação , Lactobacillus brevis/genética , Lactobacillus brevis/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Probióticos , Espécies Reativas de Oxigênio/metabolismo
13.
BMC Microbiol ; 18(1): 221, 2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30577728

RESUMO

BACKGROUND: The microflora composition of the oral cavity affects oral health. Some strains of commensal bacteria confer probiotic benefits to the host. Lactobacillus is one of the main probiotic genera that has been used to treat oral infections. The objective of this study was to select lactobacilli with a spectrum of probiotic properties and investigate their potential roles in oral health. RESULTS: An oral isolate characterized as Lactobacillus brevis BBE-Y52 exhibited antimicrobial activities against Streptococcus mutans, a bacterial species that causes dental caries and tooth decay, and secreted antimicrobial compounds such as hydrogen peroxide and lactic acid. Compared to other bacteria, L. brevis BBE-Y52 was a weak acid producer. Further studies showed that this strain had the capacity to adhere to oral epithelial cells. Co-incubation of L. brevis BBE-Y52 with S. mutans ATCC 25175 increased the IL-10-to-IL-12p70 ratio in peripheral blood mononuclear cells, which indicated that L. brevis BBE-Y52 could alleviate inflammation and might confer benefits to host health by modulating the immune system. CONCLUSIONS: L. brevis BBE-Y52 exhibited a spectrum of probiotic properties, which may facilitate its applications in oral care products.


Assuntos
Cárie Dentária/microbiologia , Lactobacillus brevis/fisiologia , Probióticos/isolamento & purificação , Adulto , Cárie Dentária/tratamento farmacológico , Feminino , Humanos , Lactobacillus brevis/genética , Lactobacillus brevis/isolamento & purificação , Masculino , Boca/microbiologia , Probióticos/administração & dosagem , Saliva/microbiologia , Streptococcus mutans/fisiologia , Adulto Jovem
14.
Sci Rep ; 8(1): 5684, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29632321

RESUMO

Sourdough fermentation by lactic acid bacteria is commonly used in bread baking, affecting several attributes of the final product. We analyzed whole-grain wheat and rye breads and doughs prepared with baker's yeast or a sourdough starter including Candida milleri, Lactobacillus brevis and Lactobacillus plantarum using non-targeted metabolic profiling utilizing LC-QTOF-MS. The aim was to determine the fermentation-induced changes in metabolites potentially contributing to the health-promoting properties of whole-grain wheat and rye. Overall, we identified 118 compounds with significantly increased levels in sourdough, including branched-chain amino acids (BCAAs) and their metabolites, small peptides with high proportion of BCAAs, microbial metabolites of phenolic acids and several other potentially bioactive compounds. We also identified 69 compounds with significantly decreased levels, including phenolic acid precursors, nucleosides, and nucleobases. Intensive sourdough fermentation had a higher impact on the metabolite profile of whole-grain rye compared to milder whole-grain wheat sourdough fermentation. We hypothesize that the increased amount of BCAAs and potentially bioactive small peptides may contribute to the insulin response of rye bread, and in more general, the overall protective effect against T2DM and CVD.


Assuntos
Pão/análise , Candida/fisiologia , Lactobacillales/fisiologia , Metabolômica/métodos , Secale/microbiologia , Triticum/microbiologia , Aminoácidos de Cadeia Ramificada/análise , Pão/microbiologia , Cromatografia Líquida , Fermentação , Hidroxibenzoatos/análise , Lactobacillus brevis/fisiologia , Lactobacillus plantarum/fisiologia , Peptídeos/análise , Análise de Componente Principal , Espectrometria de Massas em Tandem
15.
Carbohydr Polym ; 184: 435-444, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29352939

RESUMO

The knowledge about the association of lignocellulosic biomass-degrading microbes with lactic acid bacteria (LAB) in ensilages is still limited. Paenibacillus strains are important microbes in sustainable agriculture. Here, P. panacisoli SDMCC050309 was isolated from ensiled corn stover and used as an example to investigate the effects on LAB. This strain produced at least 7 xylanases, and two of them were purified and characterized. Temperature and pH optima were determined to be 55 °C and 8.0 for Xyn10 and 40 °C and 7.0 for Xyn11, respectively. They could degraded larch wood xylan and alkali-pretreated corn stover into xylooligosaccharides (XOS). Using the produced XOS to culture Lactobacillus brevis SDMCC050297 and L. parafarraginis SDMCC050300, both of them grew well with high level of acetic acid production. The same phenomenon was observed when co-culturing those two Lactobacillus strains with P. panacisoli SDMCC050309. Therefore, P. panacisoli enhances growth of LAB by producing XOS in corn stover ensilages.


Assuntos
Glucuronatos/metabolismo , Oligossacarídeos/metabolismo , Zea mays/química , Ácido Acético/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Lactobacillus brevis/fisiologia , Paenibacillus/enzimologia
16.
Probiotics Antimicrob Proteins ; 10(4): 740-747, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-28852985

RESUMO

We performed a randomized double-blind controlled trial to compare the efficacy and safety of multistrain probiotic and acyclovir in women patients with recurrent genital herpes simplex virus type 2 (HSV-2) infections. Eighty-one patients enrolled in the study were being treated with multistrain Lactobacillus brevis one vaginal capsule every 12 h and oral acyclovir 400 mg twice daily for 6 months. Of 53 patients who completed both treatment courses, no important differences were identified between acyclovir and probiotic for the primary and secondary efficacy endpoint, resolution of episode (hazard ratio, 0.60; 95% CI, 0.3429 to 1.0663; P = 0.08), lesion healing time (hazard ratio, 0.57; 95% CI, 0.3034 to 1.0717, P = 0.08), viral shedding (hazard ratio, 0.54; 95% CI, 0.3027 to 0.9750, P = 0.04), and percentage of pain (hazard ratio, 0.48; 95% CI, 0.2708 to 0.8545, P = 0.01). The median time to first and second recurrence after treatment were 43 and 121 days in patients receiving acyclovir and 33 and 118 days in patients receiving probiotic (HR 2.61; 95% CI, 1.4427 to 4.7546, P = 0.001, and HR 0.62; 95% CI, 0.3500 to 1.1133, P = 0.1, respectively). No clinically important effects happened during the probiotic treatment but some of adverse events reported in patients taking acyclovir. Easy availability, low cost, and no side effect of L. brevis are valuable properties of probiotic therapy compared with acyclovir. Therefore, we concluded that multistrain L. brevis could play an important role in suppression of recurrent genital herpes simplex virus infection.


Assuntos
Aciclovir/administração & dosagem , Antivirais/administração & dosagem , Herpes Genital/tratamento farmacológico , Lactobacillus brevis/fisiologia , Probióticos/administração & dosagem , Aciclovir/efeitos adversos , Administração Intravaginal , Adolescente , Adulto , Antivirais/efeitos adversos , Feminino , Herpesvirus Humano 2/efeitos dos fármacos , Herpesvirus Humano 2/fisiologia , Humanos , Pessoa de Meia-Idade , Recidiva , Eliminação de Partículas Virais/efeitos dos fármacos , Adulto Jovem
17.
Probiotics Antimicrob Proteins ; 10(2): 201-209, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29150754

RESUMO

Aflatoxins are a large group of highly toxic, mutagenic, and carcinogenic mycotoxins produced by specific species of fungi. Potential contamination of food commodities by these compounds causes extensive damage that lead to great economic losses. This study explored the potential use of antifungal compounds, produced by Lactobacillus brevis and Lactobacillus paracasei, for growth inhibition and subsequent aflatoxin B1 production from select strains of Aspergillus flavus and Aspergillus parasiticus. Lactobacilli strains were isolated from traditional Egyptian dairy products, whereas fungal strains were isolated from infected cereal seeds. There were noticeable decreases in mycelium biomass and aflatoxin production as well. L. brevis exhibited the highest reduction of aflatoxin B1 production by A. flavus and A. parasiticus, 96.31 and 90.43%, respectively. The concentrations of amino acids of the antifungal compound produced by L. brevis were significantly higher than that produced by L. paracasei. Asparagine, glutamine, glycine, alanine, and leucine were the most concentrated amino acids for both strains. The antifungal compounds produced by L. brevis and L. paracasei were active in a wide range of pH, heat stable and inactivated by proteolytic enzymes (protease K and trypsin A). The expression of Omt-A gene that involved in the later step of aflatoxin production was evaluated by real-time PCR. There was a vigorous reduction at transcriptional level of Omt-A gene observed in A. flavus that is treated by L. brevis and L. paracasei (80 and 70%, respectively). However, the reduction of Omt-A gene observed in A. parasiticus that is treated by L. brevis and L. paracasei was 64.5 and 52%, respectively. Treating maize seeds with antifungal compounds exhibited great efficiency in controlling fungal infection and increasing seed germination. The results confirmed that lactic acid bacteria are a promising strategy to control food contamination of fermented food and dairy products.


Assuntos
Aflatoxina B1/metabolismo , Antibiose , Aspergillus flavus/metabolismo , Laticínios/microbiologia , Lactobacillus brevis/fisiologia , Lactobacillus paracasei/fisiologia , Aspergillus flavus/genética , Egito , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Lactobacillus brevis/genética , Lactobacillus brevis/isolamento & purificação , Lactobacillus paracasei/genética , Lactobacillus paracasei/isolamento & purificação , Sementes/microbiologia , Zea mays/microbiologia
18.
Microb Pathog ; 112: 135-141, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28963009

RESUMO

This study aimed at evaluating the functional and probiotic properties of three lactic acid bacterial (LAB) strains isolated from kimchi. The selected LAB strains, which had potential probiotic functions, were identified by 16S rRNA sequence analysis as Lactobacillus brevis G1, L. brevis KU15006, and Lactobacillus curvatus KCCM 200173. All LAB strains were able to tolerate incubation at pH 2.5 with 0.3% pepsin for 3 h and with 0.3% Oxgall for 24 h and showed similar enzyme production levels, antimicrobial activities, and antibiotic susceptibilities. L. brevis G1 and KU15006 presented higher adhesion ability, auto-aggregation, and cell surface hydrophobicity than Lactobacillus rhamnosus KCTC 12202BP, a commercial strain used as positive control. All LAB strains showed 50-60% co-aggregation activity with selected foodborne pathogens. L. brevis KU15006 showed anti-adhesion activity against Escherichia coli and Salmonella Typhimurium. In addition, cell-free supernatant and cell-free extract from L. brevis KU15006 displayed the highest inhibitory activities against α-glucosidase. These results indicate that L. brevis KU15006 has the best properties, with pathogen antagonistic and antidiabetic activity, for use in probiotic products.


Assuntos
Aderência Bacteriana , Alimentos e Bebidas Fermentados/microbiologia , Doenças Transmitidas por Alimentos/terapia , Hipoglicemiantes , Lactobacillus brevis/isolamento & purificação , Lactobacillus brevis/fisiologia , Probióticos , Aclimatação , Adesinas Bacterianas , Adesinas de Escherichia coli , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antibiose/fisiologia , Ácidos e Sais Biliares , Células CACO-2 , Ativação Enzimática , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lactobacillus/genética , Lactobacillus brevis/classificação , Lactobacillus brevis/genética , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Salmonella typhimurium , Análise de Sequência , Especificidade da Espécie , alfa-Glucosidases
19.
J Appl Microbiol ; 123(2): 535-543, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28632956

RESUMO

AIMS: Atopic dermatitis (AD) is an allergic skin disease driven by the Th2-prone immune response. Therefore, a fundamental approach to restoring the Th1/Th2 balance is needed to treat AD. METHODS AND RESULTS: Eighteen different Lactobacillus strains isolated from Kimchi were screened to identify those that stimulated immune cells to secret Th1-type or Th2-type cytokines. Lactobacillus brevis NS1401 induced the greatest IFN-γ and IL-12 secretion and the least IL-4 production among the tested Lactobacillus strains. Furthermore, oral administration of heat-killed NS1401 ameliorated the symptoms of dust mite-induced AD in NC/Nga mice by decreasing the serum IgE level and reducing the number of mast cells and eosinophils in lesions. Also, the size and number of cells in the draining lymph nodes of NS1401-administered mice were significantly reduced. In agreement with these results, secretion of a Th1-type cytokine (IFN-γ) and allergen-specific IgG2a were increased, whereas secretion of Th2-type cytokines (IL-4, IL-5, and IL-10) and allergen-specific IgG1 were decreased upon administration of NS1401 in mice. CONCLUSIONS: Lactobacillus brevis NS1401 alleviates the symptoms of AD by restoring the Th1/Th2 balance through enhancing Th1-prone immunity. SIGNIFICANCE AND IMPACT OF THE STUDY: The immunomodulatory function of L. brevis NS1401 may provide effective new therapeutics against AD.


Assuntos
Brassica/microbiologia , Dermatite Atópica/microbiologia , Lactobacillus brevis/imunologia , Probióticos/administração & dosagem , Pyroglyphidae/imunologia , Animais , Dermatite Atópica/imunologia , Feminino , Temperatura Alta , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-4/imunologia , Lactobacillus brevis/química , Lactobacillus brevis/isolamento & purificação , Lactobacillus brevis/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/química , Pele/patologia , Células Th2/imunologia
20.
FEMS Microbiol Lett ; 364(6)2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333177

RESUMO

Bioluminescent imaging (BLI) has become a useful tool for monitoring bacterial infections in real time. Citrobacter rodentium and its BLI are widely used as a murine model of enteropathogenic and enterohaemorrhagic Escherichia coli infection. In this study, we evaluated the protective effects of the probiotic Lactobacillus brevis KB290 against C. rodentium infection by the BLI approach. First, we examined several solutions for making the suspension of bioluminescent C. rodentium for an oral inoculation to establish a stable intestinal infection. Three percent NaHCO3 solution was found to be the best. Subsequently, mice were orally administered KB290 once daily for 7 days before inoculation with bioluminescent C. rodentium and for 8 days after infection. The bioluminescence intensity of mice fed with KB290 was significantly lower than that of unfed mice on days 1-3 after infection. The mRNA levels of tumour necrosis factor-α and interferon-γ in the distal colon from KB290-fed mice were shown to be significantly higher than those from unfed mice on day 3 after infection. The results suggested that KB290 intake partially inhibited the proliferation of C. rodentium, especially in the early stages of infection, viathe moderate enhancement of tumour necrosis factor-α and interferon-γ production in the colon.


Assuntos
Antibiose , Citrobacter rodentium/fisiologia , Infecções por Enterobacteriaceae/diagnóstico por imagem , Infecções por Enterobacteriaceae/microbiologia , Lactobacillus brevis/fisiologia , Medições Luminescentes , Animais , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Citocinas/genética , Citocinas/metabolismo , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/metabolismo , Feminino , Expressão Gênica , Mediadores da Inflamação/metabolismo , Medições Luminescentes/métodos , Camundongos , Probióticos/administração & dosagem
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