RESUMEN
This work developed and characterized the physicochemical properties of a type A gelatin and amidated low-methoxyl pectin complex coacervate (GA-LMAP-CC) hydrogel and evaluated its suitability for preserving the viability of probiotics under in vitro gastrointestinal conditions. The formation of GA-LMAP-CC was achieved via height electrostatic attraction at pH 3 and a mixing ratio of 1, exhibiting thermoreversible gel behavior. The hydrogel had a porosity of 44% and a water absorption capacity of up to 12 times. Water absorption profiles were obtained at different pH values (2, 5, and 7). The influence of GA-LMAP-CC depended on the medium, which controlled the hydration and water absorption rate. GA-LMAP-CC promoted the viability of B. longum BB536 and L. acidophilus strains under simulated gastrointestinal conditions, thereby enhancing their potential for intestinal colonization. The hydrogel has suitable properties for potential application in food and pharmaceutical areas to encapsulate and preserve probiotics.
Asunto(s)
Gelatina , Hidrogeles , Pectinas , Probióticos , Pectinas/química , Gelatina/química , Probióticos/química , Hidrogeles/química , Viabilidad Microbiana/efectos de los fármacos , Lactobacillus acidophilus/química , Lactobacillus acidophilus/crecimiento & desarrollo , Lactobacillus acidophilus/metabolismo , Bifidobacterium/crecimiento & desarrollo , Bifidobacterium/metabolismo , Concentración de Iones de Hidrógeno , Tracto Gastrointestinal/metabolismo , Tracto Gastrointestinal/microbiologíaRESUMEN
Probiotics viability and stability is a core challenge for the food processing industry. To prolong the viability of probiotics (Lactobacillus acidophilus), gelatin (GE)-chitosan (CH) polyelectrolytes-coated nanoliposomes were developed and characterized. The average particle size of the nanoliposomes was in the range of 131.7-431.6 nm. The mean zeta potential value of the nanoliposomes differed significantly from -42.2 to -9.1 mV. Scanning electron micrographs indicated that the nanoliposomes were well distributed and had a spherical shape with a smooth surface. The Fourier transform infrared spectra revealed that the GE-CH polyelectrolyte coating has been effectively applied on the surface of nanoliposomes and L. acidophilus cells were successfully encapsulated in the lipid-based nanocarriers. X-ray diffraction results indicated that nanoliposomes are semicrystalline and GE-CH polyelectrolyte coating had an influence on the crystalline nature of nanoliposomes. Moreover, the coating of L. acidophilus-loaded nanoliposomes with GE-CH polyelectrolytes significantly improved its viability when exposed to simulated gastrointestinal environments. The findings of the current study indicated that polyelectrolyte-coated nanoliposomes could be used as an effective carrier for the delivery of probiotics and their application to food matrix for manufacturing functional foods.
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Quitosano , Probióticos , Polielectrolitos , Probióticos/química , Tracto Gastrointestinal/microbiología , Lactobacillus acidophilus/química , Tamaño de la Partícula , Quitosano/químicaRESUMEN
A number of studies have confirmed the relationship between constipation and gut microbiota. Additionally, many human and animal experiments have identified probiotics as effectors for the relief of constipation symptoms. In this study, probiotic compounds, including Lactobacillus acidophilus LA11-Onlly, Lacticaseibacillus rhamnosus LR22, Limosilactobacillus reuteri LE16, Lactiplantibacillus plantarum LP-Onlly, and Bifidobacterium animalis subsp. lactis BI516, were administered to mice with loperamide-induced constipation, and the impacts of these strains on constipation-related indicators and gut microbiota were evaluated. The effects of probiotic compounds on constipation relief were associated with various aspects, including gastrointestinal transit rate, number and weight of stools, serum and intestinal gastrointestinal regulatory hormones, and serum cytokines. Some of the probiotic compounds, including Limosilactobacillus reuteri, Lactiplantibacillus plantarum, and Lacticaseibacillus rhamnosus, were found to colonize the intestinal tract. Furthermore, higher dosages promoted the colonization of specific strains. This study yields a new perspective for the clinical use of probiotics to improve constipation symptoms by combining strains with different mechanisms for the alleviation of constipation.
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Estreñimiento/tratamiento farmacológico , Microbioma Gastrointestinal , Tracto Gastrointestinal/efectos de los fármacos , Probióticos/farmacología , Animales , Estreñimiento/microbiología , Citocinas/metabolismo , Heces/microbiología , Tracto Gastrointestinal/microbiología , Lactobacillus acidophilus/química , Lacticaseibacillus rhamnosus/química , Masculino , Ratones , Ratones Endogámicos BALB CRESUMEN
Lactobacillus is a genus of Gram-positive bacteria and comprises a major part of the lactic acid bacteria group that converts sugars to lactic acid. Lactobacillus species found in the gut microbiota are considered beneficial to human health and commonly used in probiotic formulations, but their molecular functions remain poorly defined. Microbes require metal ions for growth and function and must acquire them from the surrounding environment. Therefore, lactobacilli need to compete with other gut microbes for these nutrients, although their metal requirements are not well-understood. Indeed, the abundance of lactobacilli in the microbiota is frequently affected by dietary intake of essential metals like zinc, manganese, and iron, but few studies have investigated the role of metals, especially zinc, in the physiology and metabolism of Lactobacillus species. Here, we investigated metal uptake by quantifying total cellular metal contents and compared how transition metals affect the growth of two distinct Lactobacillus species, Lactobacillus plantarum ATCC 14917 and Lactobacillus acidophilus ATCC 4356. When grown in rich or metal-limited medium, both species took up more manganese, zinc, and iron compared with other transition metals measured. Distinct zinc-, manganese- and iron-dependent patterns were observed in the growth kinetics for these species and while certain levels of each metal promoted the growth kinetics of both Lactobacillus species, the effects depend significantly on the culture medium and growth conditions. IMPORTANCE The gastrointestinal tract contains trillions of microorganisms, which are central to human health. Lactobacilli are considered beneficial microbiota members and are often used in probiotics, but their molecular functions, and especially those which are metal-dependent, remain poorly defined. Abundance of lactobacilli in the microbiota is frequently affected by dietary intake of essential metals like manganese, zinc, and iron, but results are complex, sometimes contradictory, and poorly predictable. There is a significant need to understand how host diet and metabolism will affect the microbiota, given that changes in microbiota composition are linked with disease and infection. The significance of our research is in gaining insight to how metals distinctly affect individual Lactobacillus species, which could lead to novel therapeutics and improved medical treatment. Growth kinetics and quantification of metal contents highlights how distinct species can respond differently to varied metal availability and provide a foundation for future molecular and mechanistic studies.
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Hierro/metabolismo , Lactobacillus acidophilus/crecimiento & desarrollo , Lactobacillus acidophilus/metabolismo , Lactobacillus plantarum/crecimiento & desarrollo , Lactobacillus plantarum/metabolismo , Manganeso/metabolismo , Zinc/metabolismo , Cinética , Lactobacillus acidophilus/química , Lactobacillus plantarum/químicaRESUMEN
The role of probiotics in the prevention of ventilator-associated pneumonia (VAP) remains inconclusive. The aim of this study was to assess the efficacy of a probiotic regimen for VAP prophylaxis in mechanically ventilated multi-trauma patients, intubated immediately after the injurious insult. In a randomized, placebo-controlled study enrolling multi-trauma patients, patients expected to require mechanical ventilation for >10 days were assigned at random to receive prophylaxis with a probiotic formula (n=59) or placebo (n=53). The probiotic formula was a preparation of Lactobacillus acidophilus LA-5 [1.75 × 109 colony-forming units (cfu)], Lactobacillus plantarum (0.5 × 109 cfu), Bifidobacterium lactis BB-12 (1.75 × 109 cfu) and Saccharomyces boulardii (1.5 × 109 cfu) in sachets. Each patient received two sachets twice daily for 15 days: one through the nasogastric tube and one spread on the oropharynx. The incidence of VAP was the primary endpoint. The incidence of other infections and sepsis, and the duration of hospital stay were the secondary endpoints. Administration of probiotics reduced the incidence of VAP [11.9% vs 28.3%, hazard ratio (HR) 0.34, 95% confidence interval (CI) 0.13-0.92; P=0.034] and sepsis [6.8% vs 24.5%, odds ratio 0.22, 95% CI 0.07-0.74: P=0.016]. Furthermore, probiotic prophylaxis reduced the time of stay in the intensive care unit (ICU) and the length of hospital stay. The prophylactic use of probiotics with a combination of enteral and topical application to the oropharynx had a positive effect on the incidence of VAP and sepsis, as well as on ICU and total hospital stay in patients receiving protracted mechanical ventilation.
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Profilaxis Antibiótica , Bifidobacterium animalis/química , Lactobacillus acidophilus/química , Lactobacillus plantarum/química , Neumonía Asociada al Ventilador/tratamiento farmacológico , Probióticos/uso terapéutico , Saccharomyces boulardii/química , Adulto , Femenino , Grecia , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Probiotic L. acidophilus La-14 cells were co-encapsulated with Ganoderma lingzhi extract to prolong the viability of the cells under simulated gastrointestinal (SGI) condition and to protect the active ingredients of Reishi mushroom during the storage period. Combinations of distinctive reagents (sodium alginate, chitosan, maltose, Hydroxyethyl-cellulose (HEC), hydroxypropyl methylcellulose (HPMC), and calcium lactate) were tested. Optimal double layer Ca-alginate hydrogel beads were fabricated with significantly improved characteristics. The incorporation of maltose significantly decreases the release rate of mushrooms' phenolics, antioxidants, and ß-glucan during the storage time. Significant improvement in probiotic cells viability under SGI condition has been found and confirmed by confocal laser microscopy in maltose containing double layer coated calcium alginate beads variants. The encapsulation of newly formulated prebiotic Reishi extract and probiotic L. acidophilus is creating a new potential food application for such medicinal mushrooms and natural products with unpleasant taste upon oral consumption.
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Agaricales/química , Alginatos/química , Productos Biológicos/química , Ganoderma/química , Lactobacillus acidophilus/química , Probióticos/química , Antioxidantes/química , Antioxidantes/farmacología , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Fraccionamiento Químico/métodos , Fenómenos Químicos , Composición de Medicamentos/métodos , Glucosa/química , Metilcelulosa/química , beta-Glucanos/químicaRESUMEN
The effect of bioprotective extracts (BEs) from Lactobacillus acidophilus CRL641 (BE-1) and Latilactobacillus curvatus CRL705 (BE-2) against the exopolysaccharide producer Latilactobacillus sakei CRL1407 in vacuum-packaged meat discs at 4 °C was evaluated. Lat. sakei CRL1407 was able to grow in control samples from 2.80 to 7.77 log CFU/g after 38 days. BE-1 and BE-2 reduced bacterial growth by 2.11 and 1.35 log CFU/g, respectively, but their combination led to a greater growth reduction (3.31 log CFU/g). The antimicrobial activity was detected in treated samples with BE-1 and BE-1 + BE-2 until day 16, while with BE-2 only at the initial time. The pH values remained constant in the discs treated with the BEs combination, whereas the greatest drop in pH was observed in control samples. The minor lipid oxidation without perceptible color changes was detected in the presence of BE-1 and BE-1 + BE-2. The combination of BEs as biocontrol agent plus conventional preservation barriers could extend the fresh meat shelf-life without quality loss.
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Conservantes de Alimentos/farmacología , Lactobacillaceae/química , Lactobacillaceae/efectos de los fármacos , Lactobacillus acidophilus/química , Carne Roja/microbiología , Animales , Bovinos , Microbiología de Alimentos , Embalaje de Alimentos , Conservación de Alimentos/métodos , Concentración de Iones de Hidrógeno , Lactobacillaceae/crecimiento & desarrollo , Carne Roja/análisis , VacioRESUMEN
Obesity, a major healthcare problem worldwide, induces metabolic endotoxemia through the gut translocation of lipopolysaccharides (LPS), a major cell wall component of Gram-negative bacteria, causing a chronic inflammatory state. A combination of several probiotics including Lactobacillus acidophilus 5 (LA5), a potent lactic acid-producing bacterium, has previously been shown to attenuate obesity. However, data on the correlation between a single administration of LA5 versus microbiota alteration might be helpful for the probiotic adjustment. LA5 was administered daily together with a high-fat diet (HFD) for 8 weeks in mice. Furthermore, the condition media of LA5 was also tested in a hepatocyte cell-line (HepG2 cells). Accordingly, LA5 attenuated obesity in mice as demonstrated by weight reduction, regional fat accumulation, lipidemia, liver injury (liver weight, lipid compositions, and liver enzyme), gut permeability defect, endotoxemia, and serum cytokines. Unsurprisingly, LA5 improved these parameters and acidified fecal pH leads to the attenuation of fecal dysbiosis. The fecal microbiome analysis in obese mice with or without LA5 indicated; (i) decreased Bacteroidetes (Gram-negative anaerobes that predominate in non-healthy conditions), (ii) reduced total fecal Gram-negative bacterial burdens (the sources of gut LPS), (iii) enhanced Firmicutes (Gram-positive bacteria with potential benefits) and (iv) increased Verrucomycobia, especially Akkermansia muciniphila, a bacterium with the anti-obesity property. With LA5 administration, A. muciniphila in the colon were more than 2,000 folds higher than the regular diet mice as determined by 16S rRNA. Besides, LA5 produced anti-inflammatory molecules with a similar molecular weight to LPS that reduced cytokine production in LPS-activated HepG2 cells. In conclusion, LA5 attenuated obesity through (i) gut dysbiosis attenuation, partly through the promotion of A. muciniphila (probiotics with the difficulty in preparation processes), (ii) reduced endotoxemia, and (iii) possibly decreased liver injury by producing the anti-inflammatory molecules.
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Disbiosis/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Obesidad/tratamiento farmacológico , Probióticos/farmacología , Akkermansia/efectos de los fármacos , Akkermansia/crecimiento & desarrollo , Animales , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Disbiosis/dietoterapia , Disbiosis/microbiología , Disbiosis/patología , Humanos , Lactobacillus acidophilus/química , Lactobacillus acidophilus/metabolismo , Ratones , Ratones Obesos , Obesidad/etiología , Obesidad/microbiología , Obesidad/patología , Probióticos/química , ARN Ribosómico 16S/genéticaRESUMEN
The effect of bioprotective extracts (BEs) from Latilactobacillus curvatus CRL705 and Lactobacillus acidophilus CRL641 against Latilactobacillus sakei CRL1407 was evaluated in a refrigerated meat model system under vacuum and aerobic conditions at 4 and 10 °C. As shown by culturing, the BE-1 from L. acidophilus completely inhibited the spoilage strain, while that from Lat. Curvatus CRL705 (BE-2) and its combination with BE-1 exerted a bacteriostatic effect. The antimicrobial activity and exopolysaccharide production correlated with the efficacy of inhibitory treatment while final pH decrease was higher in control samples. When flow cytometry was applied, a lack of correlation with plate counting was found; counts under the detection limit for BE-1 at 21 and 28 days at 4 and 10 °C represented between 64.15 and 73.70% of dead cells. Thus, the concurrence of lactic acid bacteria as biocontrol agents and the use of more accurate tools to prevent the growth of deteriorating species will contribute to the extension of fresh meat shelf-life without quality loss.
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Conservantes de Alimentos/farmacología , Lactobacillaceae/efectos de los fármacos , Lactobacillus acidophilus/química , Lactobacillus/química , Carne/microbiología , Animales , Embalaje de Alimentos , Conservación de Alimentos/instrumentación , Conservación de Alimentos/métodos , Conservantes de Alimentos/química , Lactobacillaceae/crecimiento & desarrollo , Lactobacillaceae/metabolismo , Refrigeración , VacioRESUMEN
This work describes a new procedure that allows the targeted modification of the human gut microbiota by using antibodies raised against bacterial surface-associated proteins specific to the microorganism of interest. To this end, a polyclonal antibody recognising the surface-associated protein Surface Layer Protein A of Lactobacillus acidophilus DSM20079T was developed. By conjugating this antibody with fluorescent probes and magnetic particles, we were able to specifically identify this bacterium both in a synthetic, and in real gut microbiotas by means of a flow cytometry approach. Further, we demonstrated the applicability of this antibody to deplete complex human gut microbiotas from L. acidophilus in a single step. L. acidophilus was found to interact with other bacteria both in synthetic and in real microbiotas, as reflected by its concomitant depletion together with other species. Further optimization of the procedure including a trypsin step enabled to achieve the selective and complete isolation of this species. Depleting a single species from a gut microbiota, using antibodies recognizing specific cell surface elements of the target organism, will open up novel ways to tackle research on the specific immunomodulatory and metabolic contributions of a bacterium of interest in the context of a complex human gut microbiota, including the investigation into therapeutic applications by adding/depleting a key bacterium. This represents the first work in which an antibody/flow-cytometry based application enabled the targeted edition of human gut microbiotas, and represents the basis for the design of precision microbiome-based therapies.
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Anticuerpos/química , Proteínas Bacterianas/aislamiento & purificación , Microbioma Gastrointestinal , Lactobacillus acidophilus/aislamiento & purificación , Proteínas Bacterianas/química , Citometría de Flujo , Humanos , Lactobacillus acidophilus/química , MicrobiotaRESUMEN
Recently, researchers have reported the presence of patulin as a mycotoxin in commercial apple products, especially apple juices. The aim of this study was to assess adsorption of patulin from artificially contaminated apple juice using two lactic acid bacteria (LAB) strains of Lactobacillus acidophilus ATCC 4356 and Lactobacillus plantarum ATCC 8014. Furthermore, effects of five physical and chemical pretreatments on the patulin adsorption were investigated. Results demonstrated that patulin adsorption abilities of both strains increased with NaOH pretreatment but decreased after autoclaving. The NaOH-treated L. plantarum ATCC 8014 showed the best removal rate (59.74%) after 48 h of refrigerated storage, compared with the NaOH-treated L. acidophilus ATCC 4356 (52.36%). Moreover, stability of the LAB-patulin complex was assessed in simulated gastrointestinal tract conditions and a low quantity of patulin was released into the solution. The patulin adsorption process by NaOH-treated L. plantarum ATCC 8014 followed Freundlich isotherm model and pseudo-second-order kinetic model. Fourier transform infrared spectroscopy showed that polysaccharide and protein components of the L. plantarum ATCC 8014 cell wall played key roles in patulin adsorption. The major functional groups of the cell wall that were involved in adsorbing patulin included -OH/-NH, -CH2, C=O, and C-O groups. The current results suggest that NaOH-treated L. plantarum ATCC 8014 cells include the potential to detoxify patulin-contaminated apple juices.
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Contaminación de Alimentos , Jugos de Frutas y Vegetales , Tracto Gastrointestinal/metabolismo , Lactobacillus acidophilus/química , Lactobacillus plantarum/química , Malus/química , Modelos Biológicos , Patulina/química , HumanosRESUMEN
BACKGROUND: The anti-cancer activity of some lactic acid bacterial strains is well documented in several kinds of literatures. Lactobacillus strains have received considerable attention as a beneficial microbiota. The aim of this study is to evaluate the effects of anti-tumor activities of L. acidophilus ATCC4356 culture supernatants on the MCF-7 human breast cancer cells. MATERIALS AND METHODS: The anti-cancer effects of 24h and 48h culture supernatants at various concentrations (1.25, 2.5, 5, 10 and 20 µg/ml) were determined by various in vitro and in vivo assays including MTT, tumor volume measurement as well as 99mTc-MIBI biodistribution in MCF-7 tumor bearing nude mice and histopathology test. For evaluation of the related mechanism of action, quantitative PCR was conducted. RESULTS: The 48h culture supernatants at 10 and 20 µg/ml exhibited significant in vitro inhibition of MCF-7 cell proliferation. However, this inhibition was not observed for HUVEC human endothelial normal cells. Q-PCR indicated that treatment by the supernatant led to a significant downregulation of VEGFR (~ 0.009 fold) and Bcl- 2 (~ 0.5 fold) and upregulation of p53 (~ 1.3 fold). In vivo study using MCF-7 xenograft mouse models demonstrated a reduction in tumor weight and volume by both 24h and 48h supernatants (2 mg/kg) after 15 days. According to the 99mTc-MIBI biodistribution result, treatment of MCF-7 bearing nude mice with both 24h and 48h supernatant (2mg/kg) led to a significant decrease in tumor uptake compared with the control group. CONCLUSION: These results suggest that the culture supernatants of L. acidophilus ATCC4356 at suitable concentrations can be considered as a good alternative nutraceutical with promising therapeutic indexes for breast cancer.
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Antineoplásicos/farmacología , Medios de Cultivo/farmacología , Lactobacillus acidophilus/química , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones DesnudosRESUMEN
This study was aimed to assess effects of three strains of probiotics Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus HN001, and Bifidobacterium animalis subsp. lactis Bi-07 on the intestinal motility and inflammation in the zebrafish models. The intestinal motility model was established using 5 days postfertilization (dpf) zebrafish administered with a fluorescent dye Nile red at 10 ng/mL for 16 h, followed by probiotics treatment for 24 h and the intestinal motility was inversely proportional to the intestinal fluorescence intensity that was quantitatively measured by image analysis. The intestinal inflammation was induced by treating 3 dpf neutrophil fluorescent zebrafish with 0.0125% of trinitrobenzenesulfonic acid for 48 h. Probiotics were administered at low, moderate, and high concentrations determined based on maximum tolerable concentration through soaking. All three strains of probiotics promoted intestinal movement, of which B. animalis subsp. lactis Bi-07 was most potent at lower concentrations. L. rhamnosus HN001 and B. animalis subsp. lactis Bi-07 had the therapeutic effects on the intestinal inflammation and the inflammation-associated mucosal damage recovery. The anti-inflammatory mechanisms of L. rhamnosus HN001 was related to both reduce inflammatory factor interleukin-6 (IL-6) and restored tissue repair factor transforming growth factor-ß-1 (TGFß-1); whereas B. animalis subsp. lactis Bi-07 was probably only associated with TGFß-1 elevation. Using larval zebrafish models for probiotics screening and assessment would speed up product research and development and improve products' efficacy and quality.
Asunto(s)
Bifidobacterium animalis/química , Motilidad Gastrointestinal/efectos de los fármacos , Inflamación/tratamiento farmacológico , Lacticaseibacillus rhamnosus/química , Lactobacillus acidophilus/química , Probióticos/farmacología , Pez Cebra , Animales , Inflamación/fisiopatologíaRESUMEN
The present study was conducted to develop bacterial cellulose nanofibers (BCNF) and to evaluate its ability as a carrier material for the incorporation of the probiotic bacteria Lactobacillus acidophilus 016. Bacterial cellulose (5%) dissolved in trifluoroacetic acid (TFA) solution was amended with an equal volume of polyvinyl alcohol (PVA) solution to produce nanofibers via electrospinning. Fourier-transform infrared spectra of BCNF confirmed the absence of TFA used in the dissolution process. Mechanical properties, including tensile strength, surface area, pore-volume, and pore diameter, and thermal analysis of BCNF revealed that the nanofibers could be incorporated in food for the delivery of probiotics. L. acidophilus 016 was successfully immobilized onto the BCNF through the adsorption-incubation technique. SEM micrograph revealed that the immobilized bacteria sustained without any damage during the storage for up to 24 days. Further, the viability studies confirmed the survival of 71% population during the storage at 35 °C. These observations recommended the possibility of BCNF based probiotics for various commercial applications.
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Celulosa/química , Portadores de Fármacos/química , Lactobacillus acidophilus/metabolismo , Nanofibras/química , Probióticos/metabolismo , Lactobacillus acidophilus/química , Viabilidad Microbiana , Probióticos/químicaRESUMEN
A longstanding awareness in generating resistance to common antimicrobial therapies by Gram-negative bacteria has made them a major threat to global health. The application of antimicrobial peptides as a therapeutic agent would be a great opportunity to combat bacterial diseases. Here, we introduce a new antimicrobial peptide (â¼8.3 kDa) from probiotic strain Lactobacillus acidophilus ATCC 4356, designated acidocin 4356 (ACD). This multifunctional peptide exerts its anti-infective ability against Pseudomonas aeruginosa through an inhibitory action on virulence factors, bacterial killing, and biofilm degradation. Reliable performance over tough physiological conditions and low hemolytic activity confirmed a new hope for the therapeutic setting. Antibacterial kinetic studies using flow cytometry technique showed that the ACD activity is related to the change in permeability of the membrane. The results obtained from molecular dynamic (MD) simulation were perfectly suited to the experimental data of ACD behavior. The structure-function relationship of this natural compound, along with the results of transmission electron microscopy analysis and MD simulation, confirmed the ability of the ACD aimed at enhancing bacterial membrane perturbation. The peptide was effective in the treatment of P. aeruginosa infection in mouse model. The results support the therapeutic potential of ACD for the treatment of Pseudomonas infections.IMPORTANCE Multidrug-resistant bacteria are a major threat to global health, and the Pseudomonas bacterium with the ability to form biofilms is considered one of the main causative agents of nosocomial infections. Traditional antibiotics have failed because of increased resistance. Thus, finding new biocompatible antibacterial drugs is essential. Antimicrobial peptides are produced by various organisms as a natural defense mechanism against pathogens, inspiring the possible design of the next generation of antibiotics. In this study, a new antimicrobial peptide was isolated from Lactobacillus acidophilus ATCC 4356, counteracting both biofilm and planktonic cells of Pseudomonas aeruginosa A detailed investigation was then conducted concerning the functional mechanism of this peptide by using fluorescence techniques, electron microscopy, and in silico methods. The antibacterial and antibiofilm properties of this peptide may be important in the treatment of Pseudomonas infections.
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Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Proteínas Bacterianas/farmacología , Lactobacillus acidophilus/química , Pseudomonas aeruginosa/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Cinética , Simulación de Dinámica Molecular , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/patogenicidad , Pseudomonas aeruginosa/fisiología , Virulencia/efectos de los fármacosRESUMEN
Abdominal adhesions refer to abnormal adhesions which cause a series of complications in numerous patients. In the present study, the beneficial effect of a combination of probiotics (Lactobacillus plantarum, L. acidophilus, L. rhamnosus and Bifidobacterium animalis) on abdominal adhesions in a rat model were verified. The present results indicated that probiotic treatment significantly reduced the levels of proinflammatory factors interleukin (IL)1ß, IL6 and TNFα in serum and intestinal tissue (P<0.05), and markedly downregulated the inflammatory (TLR4/NFκB) and fibrotic (TGFß1/Smad) signalling pathways in intestinal tissue, especially in the prevention group (P<0.01). The highthroughput sequencing results further supported that the probiotics significantly increased the relative abundance of probiotic Bacteroidetes (at the phylum level), Bacteroidales (at the order level), Lactobacillales (at the order level) and Lactobacillus (at the genus level), and markedly reduced the number of pathogenic Proteobacteria (at the phylum level), Erysipelotrichales (at the order level), Verrucomicrobiales (at the order level), Klebsiella (at the genus level) and Serratia (at the genus level). In conclusion, probiotics can effectively reduce abdominal adhesions by restoring the microbial balance and reducing inflammation and fibrosis caused by surgery.
Asunto(s)
Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Inflamación/tratamiento farmacológico , Probióticos/farmacología , Animales , Bacterias/patogenicidad , Bifidobacterium animalis/química , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Inflamación/microbiología , Inflamación/patología , Interleucina-1beta/genética , Interleucina-6/genética , Intestinos/efectos de los fármacos , Intestinos/microbiología , Lactobacillus/química , Lactobacillus acidophilus/química , Lactobacillus plantarum/química , Lacticaseibacillus rhamnosus/química , Ratas , Factor de Crecimiento Transformador beta1/genéticaRESUMEN
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.
Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Arsénico/toxicidad , Lacticaseibacillus casei/química , Lactobacillus acidophilus/química , Levilactobacillus brevis/química , Probióticos/farmacología , Antiinflamatorios/química , Antioxidantes/química , Células CACO-2 , Permeabilidad de la Membrana Celular/efectos de los fármacos , Medios de Cultivo Condicionados/química , Medios de Cultivo Condicionados/farmacología , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Isoquinolinas/análisis , Isoquinolinas/metabolismo , Lactobacillus acidophilus/fisiología , Levilactobacillus brevis/fisiología , Lacticaseibacillus casei/fisiología , Estrés Oxidativo/efectos de los fármacos , Probióticos/química , Proteína de la Zonula Occludens-1/genética , Proteína de la Zonula Occludens-1/metabolismoRESUMEN
The objective of this research was to investigate the effects of Lactobacillus acidophilus CICC 6074 S-layer protein on the viability, adhesion, cell cycle, and apoptosis of human colon cancer HT-29 cells and to explore their molecular mechanism of tumor suppression. The S-layer protein at doses of 0, 25, 50, and 100 mg/L significantly suppressed the proliferation of HT-29 cells. The S-layer protein exerts its cytotoxic activities against colon cancer HT-29 cells by arresting the cell cycle in the G1 phase through upregulating the expression of p53, p21, and p16 and downregulating the expression of CDK1 (cyclin-dependent kinases) and cyclin B. Morphological changes were further observed by transmission electron microscopy, and the cells treated with the S-layer protein showed obvious characteristic changes of apoptosis including chromatin condensation, nuclear fragmentation, vacuoles, and so on. Furthermore, our mechanism studies indicated that the S-layer protein may induce HT-29 cell apoptosis through the death receptor apoptotic pathway and mitochondrial pathway and impede cell invasion by inhibiting the synthesis of the PI3K/AKT pathway and FasL. These results demonstrated that the L. acidophilus CICC 6074 S-layer protein may be a potential anticarcinogenic agent.
Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/fisiopatología , Lactobacillus acidophilus/química , Glicoproteínas de Membrana/farmacología , Proteína Quinasa CDC2/genética , Proteína Quinasa CDC2/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Ciclina B/genética , Ciclina B/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HT29 , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Many beneficial effects of probiotic Lactobacilli on cancer prevention and therapy were previously presented. So finding probiotics with proapoptotic activities is a promising approach for cancer drug discovery. Here, the antiproliferative and antioxidant activities of cell-free extracts of Lactobacillus acidophilus and Lactobacillus delbrueckii on HT-29 cell line were evaluated employing MTT and DPPH assays. The induction of apoptosis was assessed by Hoechst staining and flow cytometry analysis which was further confirmed by expression analysis of BCL-2, BAX, caspase-3, caspase-8, and caspase-9 genes using real-time quantitative PCR. Caspase-3 activity was also analyzed. Results showed that cell viability was significantly reduced to 42.2 ± 0.01% and 19.40 ± 0.01% by 5 and 8 mg ml-1 of L. acidophilus and L. delbrueckii extracts, respectively. Apoptosis induction was shown with both bacterial extracts. Caspase-9 and caspase-3 overexpression as well as Bax/Bcl-2 ratio increase revealed the ability of both probiotics to induce intrinsic pathway-dependent apoptosis. The extrinsic pathway was also activated by L. acidophilus. At the concentration of 198 µg ml-1, L. acidophilus and L. delbrueckii had a DPPH scavenging activity of 59.37 ± 3.97% and 71.19 ± 3.64%, respectively. Taken together, these findings provide evidence for antiproliferative, proapoptotic, and antioxidant effects driven by these probiotic lactic acid bacteria (LAB) strains.
Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Neoplasias del Colon/tratamiento farmacológico , Lactobacillus acidophilus/química , Lactobacillus delbrueckii/química , Probióticos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Células HT29 , HumanosRESUMEN
A newly developed molecularly imprinted photonic polymer (MIPP) film, which was prepared by colloidal crystal templating and surface molecular imprinting, was used for selective capture of S-layer protein (SLP) from a complex Lactobacillus acidophilus sample. The colloidal crystal templates were formed by a dipping process followed by chemical binding of the imprinted template SLP molecules. A sandwich structure consisting of two glass slides was formed after the SLP-silica layer had been covered with a poly(methyl methacrylate) glass slide. After polymerization of the SLP-silica layer with the preprepared polymerization solution, hydrofluoric acid and acetic phosphate buffer solutions removed the silica particles and SLP molecules, respectively. The MIPP film obtained exhibited a three-dimensional, highly ordered and interconnected macroporous structure (pore size greater than 200 nm), which is specifically accessible to SLP molecules. The adsorbed SLP molecules were simply and straightforwardly detected by a fiber-optic spectrometer. The redshift of the Bragg diffraction peak of the MIPP film was linearly related to the number of SLP molecules that had been harvested in the film. The detection limit of the SLP-MMIP-fiber-optic spectrometer method for SLP was 1 ng mL-1. The MIPP sensor was successfully applied to detect SLP molecules in a crudely extracted Lactobacillus acidophilus sample. Our results prove the applicability of the SLP-MIPP film for fast and real-time measurement of SLP. Graphical abstract.