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1.
Front Cell Infect Microbiol ; 14: 1391758, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716194

RESUMO

Campylobacter jejuni, a Gram-negative bacterium, is one of the most common causes of foodborne illness worldwide. Its adhesion mechanism is mediated by several bacterial factors, including flagellum, protein adhesins, lipooligosaccharides, proteases, and host factors, such as surface glycans on epithelial cells and mucins. Fungal lectins, specialized carbohydrate-binding proteins, can bind to specific glycans on host and bacterial cells and thus influence pathogenesis. In this study, we investigated the effects of fungal lectins and protease inhibitors on the adhesion of C. jejuni to model biotic surfaces (mucin, fibronectin, and collagen) and Caco-2 cells as well as the invasion of Caco-2 cells. The lectins Marasmius oreades agglutinin (MOA) and Laccaria bicolor tectonin 2 (Tec2) showed remarkable efficacy in all experiments. In addition, different pre-incubations of lectins with C. jejuni or Caco-2 cells significantly inhibited the ability of C. jejuni to adhere to and invade Caco-2 cells, but to varying degrees. Pre-incubation of Caco-2 cells with selected lectins reduced the number of invasive C. jejuni cells the most, while simultaneous incubation showed the greatest reduction in adherent C. jejuni cells. These results suggest that fungal lectins are a promising tool for the prevention and treatment of C. jejuni infections. Furthermore, this study highlights the potential of fungi as a rich reservoir for novel anti-adhesive agents.


Assuntos
Aderência Bacteriana , Campylobacter jejuni , Lectinas , Inibidores de Proteases , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/fisiologia , Campylobacter jejuni/metabolismo , Humanos , Células CACO-2 , Aderência Bacteriana/efeitos dos fármacos , Lectinas/metabolismo , Lectinas/farmacologia , Inibidores de Proteases/farmacologia , Inibidores de Proteases/metabolismo , Fungos/efeitos dos fármacos , Mucinas/metabolismo , Células Epiteliais/microbiologia , Fibronectinas/metabolismo
2.
Plants (Basel) ; 12(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37836176

RESUMO

The antioxidant activity (AA) of hop extracts obtained from different hop genotypes (n = 14) was studied. For comparison, the purified ß-acids-rich fraction and α-acids-with-ß-acids-rich fraction were also used to test the antioxidative potential. The AA of purified hydroacetonic hop extracts was investigated using the Ferric Reducing Ability of Plasma (FRAP), Oxygen Radical Absorption Capacity (ORAC) and Intracellular Antioxidant (IA) methods. The FRAP values in different hop genotypes ranged between 63.5 and 101.6 µmol Trolox equivalent (TE)/g dry weight (DW), the ORAC values ranged between 1069 and 1910 µmol TE/g DW and IA potential values ranged between 52.7 and 118.0 mmol TE/g DW. Significant differences in AA between hop genotypes were observed with all three methods. AAs were determined using three different methods, which did not highly correlate with each other. We also did not find significant correlations between AA and different chemical components, which applies both to AA determined using individual methods as well as the total AA. Based on this fact, we assume that the synergistic or antagonistic effects between hop compounds have a more pronounced effect on AA than the presence and quantity of individual hop compounds.

3.
Plants (Basel) ; 12(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37653960

RESUMO

Increasing antimicrobial resistance has caused a great interest in natural products as alternatives or potentiators of antibiotics. The objective of this study was to isolate individual tannins from crude chestnut extract as well as to determine the influence of both crude extracts (tannic acid extract, chestnut extract) and individual pure tannins (gallic acid, vescalin, vescalagin, castalin, castalagin) on the growth of Gram-positive Staphylococcus aureus bacteria. Their antibacterial activity was monitored by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) as well as the duration of the lag phase, growth rate and generation time. The effect of growth medium strength on the MIC of different tannins was also investigated. Bacterial growth was followed spectrophotometrically, and MIC values were determined by the microdilution method. The MIC values of various isolated compounds allowed us to determine the bioactive compounds and their contribution to antimicrobial activity. It was found that MIC values increase with increasing growth medium strength and that the lag phase lengthens with increasing tannin concentrations, while the growth rates decrease. Comparing the results of the two studies, the antimicrobial activity of tannins against S. aureus was not as pronounced as in the case of E. coli, which may indicate that a different mechanism of action is responsible for the antimicrobial effects of tannins on Gram-positive than on Gram-negative bacteria, or that a different mechanism is more pronounced.

4.
Foods ; 12(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569132

RESUMO

For risk communication, it is important to understand the difference between "hazard" and "risk". Definitions can be found in Codex Alimentarius and the European Union (EU) General Food Regulation (EC) No. 178/2002. The use of these terms as synonyms or their interchange is a recurrent issue in the area of food safety, despite awareness-raising messages sent by EFSA (European Food Safety Authority) and other interested entities. A quick screening of the EU's food regulations revealed several inconsistencies. Hence, it was considered necessary to further investigate if regulations could act as a source for this problem. A software tool was developed to support the detection and listing of inconsistent translations of "hazard" and "risk" in certain EU food regulations. Subsequently, native-speaking experts working in food safety from each EU country were asked to provide their individual scientific opinion on the prepared list. All data were statistically analysed after applying numerical scores (1-5) describing different levels of consistency. Results showed that the most common problem was the interchange of "hazard" with "risk" and vice versa. This lack of consistency can create confusion that can further translate into misjudgments at food risk assessment and communication levels.

5.
Life (Basel) ; 13(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37240735

RESUMO

In our previous studies, Lactobacillus reuteri B1/1, which was renamed Limosilactobacillus reuteri (L. reuteri), was able to modulate the production of pro-inflammatory cytokines and other components of the innate immune response in vitro and in vivo. In this study, we evaluated the effect of Lactobacillus reuteri B1/1 in two concentrations (1 × 107 and 1 × 109 CFU) on the metabolic activity, adherence ability and relative gene expression of pro-inflammatory interleukins (IL-1ß, IL-6, IL-8, IL-18), lumican and olfactomedin 4 produced by non-carcinogenic porcine-derived enterocytes (CLAB). CLAB cells were cultured in a 12-well cell culture plate at a concentration of 4 × 105 cells/well in DMEM medium in a controlled humidified atmosphere for 48 h. A 1 mL volume of each probiotic bacterial suspension was added to the CLAB cells. Plates were incubated for 2 h and 4 h. Our results revealed that L. reuteri B1/1 was able to adhere to CLAB cells in sufficient numbers in both concentrations. In particular, the concentration of 109L. reuteri B1/1 allowed to modulate the gene expression of pro-inflammatory cytokines, as well as to increase the metabolic activity of the cells. In addition, administration of L. reuteri B1/1 in both concentrations significantly stimulated gene expression for both proteins in the CLAB cell line after 4 h of incubation.

6.
EFSA J ; 20(Suppl 2): e200905, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36531272

RESUMO

Food risk assessment plays an important role in protecting public health worldwide. Stakeholders involved in food risk assessment, such as national authorities, agencies, non-governmental organisations (NGOs), industry and consumers, need to properly understand the terminology of food risk assessment effectively. In this respect, the first part of the EU-FORA work programme (WP1) aimed to provide insights into the actual translation of two essential terms used in food risk assessment. 'Hazard' and 'risk' were first identified and compared between the English version of various food regulations and their equivalents in the national legislation of EU Member States. The comparison and critical evaluation revealed several inconsistencies. These inconsistencies could lead to misinterpretations, followed by errors in conducting risk assessments or communicating risks. We recommend that consistency is restored and maintained so that the message is properly communicated. The second part of the work programme (WP2) was focused on a specific area within chemical risk assessment (CRA). In this context, special attention was given to the impact of the food matrix on the bioaccessibility and bioavailability of heavy metals and metalloids. After collection and careful selection of data from scientific journals, a database with information on the bioaccessibility and bioavailability of cadmium (Cd), lead (Pb), mercury (Hg) and arsenic (As) in different food matrices was created for future statistical analyses related to dietary exposure.

7.
J Clin Med ; 11(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36498583

RESUMO

Urinary tract infections (UTI) are frequent bacterial infections in childhood. Considering the known beneficial effects of probiotics in the gastrointestinal field, they could also help to alleviate UTIs. In our clinical pilot study, we sought to verify the positive effects of the specific probiotic strain on the course and prevention of UTI in children. Thirty children with UTIs were enrolled and sequentially sampled into two groups (placebo/control and probiotic/test) in a double-blind, randomized, placebo-controlled clinical pilot study. We chose Lactobacillus plantarum PCS 26 (Lp26) derived from local Slovenian cheese in Pathogen Combat Project, which showed a good in vitro antimicrobial effect on Escherichia coli (E. coli). Several parameters were followed to look for differences between both groups in the acute phase of the UTI and after 6 months of taking probiotic or placebo supplementation. Our results showed no statistically significant differences between both groups; however, two children in the placebo group suffered a recurrence of febrile UTI within 6 months of the follow-up period, while there were no recurrences of UTI in the probiotic group. In the test group, the number of febrile days after the initiation of antibiotics with probiotics was shorter, although not reaching statistical significance (p = 0.084). According to our results, probiotics might be helpful in alleviating UTI symptoms and in UTI prevention. Further research with a larger sample size is warranted. Additionally, basic scientific studies for the selection of proper immunobiotic strains of probiotics should be performed.

8.
Life (Basel) ; 12(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36013366

RESUMO

The maintenance of a healthy status depends on the coexistence between the host organism and the microbiota. Early studies have already focused on the nutritional properties of probiotics, which may also contribute to the structural changes in the gut microbiota, thereby affecting host metabolism and homeostasis. Maintaining homeostasis in the body is therefore crucial and is reflected at all levels, including that of glucose, a simple sugar molecule that is an essential fuel for normal cellular function. Despite numerous clinical studies that have shown the effect of various probiotics on glucose and its homeostasis, knowledge about the exact function of their mechanism is still scarce. The aim of our review was to select in vivo and in vitro studies in English published in the last eleven years dealing with the effects of probiotics on glucose metabolism and its homeostasis. In this context, diverse probiotic effects at different organ levels were highlighted, summarizing their potential mechanisms to influence glucose metabolism and its homeostasis. Variations in results due to different methodological approaches were discussed, as well as limitations, especially in in vivo studies. Further studies on the interactions between probiotics, host microorganisms and their immunity are needed.

9.
Plants (Basel) ; 12(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36616249

RESUMO

The antimicrobial activity of hop extracts obtained from different hop genotypes were investigated against Staphylococcus aureus and Lactobacillus acidophilus. In this study the pure xanthohumol, purified ß-acids rich fraction, as well as α-acids with ß-acids rich fraction were used to test antimicrobial activity against Staphylococcus aureus and Lactobacillus acidophilus; whereby, the antimicrobial activity of different hop extracts against Lactobacillus acidophilus was studied for the first time. Microbial susceptibility to purified hydroacetonic extracts from different hop varieties was investigated by the broth microdilution assay to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The hop hydroacetonic extracts were more effective against Staphylococcus aureus than against Lactobacillus acidophilus. Strong inverse correlations of MIC and MBC values were obtained with xanthohumol, cohumulone, n+adhumulone, colupulone and n+adlupulone contents, suggesting that the identified chemical hop compounds are directly responsible for antimicrobial effects. Moreover, the effect of the growth medium strength on the MIC values of hop extracts against Staphylococcus aureus was systematically investigated for the first time. The current study also reveals the effect of different hop extracts on Staphylococcus aureus, which responds to their presence by lag phase extension and generation time prolongation.

10.
Arch Public Health ; 79(1): 68, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947465

RESUMO

BACKGROUND: Strategies to reduce salt intake are encouraged to be implemented in parallel with those that aim to ensure iodine adequacy at the population level. The aim of the present study was to assess and compare knowledge, attitudes and behaviours related to salt and iodine among students in Europe and Asia. METHODS: A multicentre cross-sectional study was conducted with 2459 university students in total (42.7% males, median age 21 years) from four countries in Europe and two countries in Asia. Data were collected with the use of a self-administered questionnaire, and univariate and multivariate statistical analyses were performed to explore any association between variables. RESULTS: Only 6.5% of all participants knew the correct salt recommendations. Nearly a quarter of them (24.4%) found salt recommendations confusing and/or contradictory. There were significant differences between European and Asian participants, with those from Europe being better informed about salt recommendations, but significantly less knowledgeable about iodine. The reported frequency of use of salt and salt-containing sauces either at the table or for cooking, as well as knowledge about ways to reduce salt intake among those who indicated to make conscious efforts to do so, differed significantly between countries. Significant differences between countries were also observed with respect to the type of salt used, with about one third of all participants (34%) not being aware of the kind of salt they used. CONCLUSION: The results of this survey highlight serious salt- and iodine-related knowledge gaps among university students in Europe and Asia. Raising awareness and conducting information campaigns is needed to promote changes in behaviour that would result in a reduction of salt intake and conscious use of iodised salt at the individual level.

11.
Nutr Res ; 86: 10-22, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450655

RESUMO

Although human clinical studies have suggested probiotic effects on blood glucose levels, knowledge about molecular mechanisms is still scarce. To test the hypothesis that selected Lactobacillus probiotic bacteria could regulate the activity of enterocyte glucose transporters, we aimed to measure in vitro effects of selected Lactobacillus probiotic bacteria on transcription and translation of intestinal glucose transporters sodium-dependent glucose cotransporter 1 (SGLT1) and glucose transporter 2 (GLUT2) as well as transepithelial glucose transport. Lactobacillus plantarum strains (PCS20 and PCS26), Lactobacillus rhamnosus GG (LGG) (ATCC 53103) and Lactobacillus acidophilus (L acidophilus) (ATCC 4356) were co-cultivated with noncarcinogenic porcine enterocytes (CLAB) and human epithelial colorectal adenocarcinoma cells (Caco-2) (ATCC HTB-37). Changes in transcription and expression of SGLT1 and GLUT2 were strain and cell line-specific. In CLAB, LGG was the most potent SGLT1 up-regulator, and PCS26 the most potent down-regulator of GLUT2 transcription, which was also reflected on the protein level. In Caco-2, all tested strains tended to downregulate GLUT2 gene expression, while L acidophilus most effectively reduced GLUT2 protein levels. Statistically significant effect of PCS26 and L acidophilus on GLUT2 molecular and protein levels in CLAB and Caco-2 cell lines, respectively, was also followed by a decreased rate of transepithelial glucose transport. Careful selection of specific Lactobacillus probiotic strains could be used to downregulate glucose absorption in intestinal epithelial cells and thereby could be beneficial as a support treatment of pathologies related to glucose homeostasis.


Assuntos
Enterócitos/metabolismo , Transportador de Glucose Tipo 2/genética , Glucose/metabolismo , Mucosa Intestinal/metabolismo , Lactobacillus , Probióticos , Animais , Transporte Biológico , Células CACO-2 , Linhagem Celular , Regulação para Baixo , Células Epiteliais/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Humanos , Mucosa Intestinal/citologia , Transportador 1 de Glucose-Sódio/genética , Transportador 1 de Glucose-Sódio/metabolismo , Suínos , Transcrição Gênica
12.
BMC Vet Res ; 16(1): 34, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013961

RESUMO

BACKGROUND: Campylobacter spp. are a major cause of bacterial food-borne diarrhoeal disease. This mainly arises through contamination of meat products during processing. For infection, Campylobacter spp. must adhere to epithelial cells of the mucus layer, survive conditions of the gastrointestinal tract, and colonise the intestine of the host. Addition of probiotic bacteria might promote competitive adhesion to epithelial cells, consequently reducing Campylobacter jejuni colonisation. Effect of Lactobacillus spp. (PCS20, PCS22, PCS25, LGG, PCK9) on C. jejuni adhesion, invasion and translocation in pig (PSI cl.1) and chicken (B1OXI) small-intestine cell lines, as well as pig enterocytes (CLAB) was investigated. RESULTS: Overall, in competitive adhesion assays with PSI cl.1 and CLAB cell monolayers, the addition of Lactobacillus spp. reduced C. jejuni adherence to the cell surface, and negatively affected the C. jejuni invasion. Interestingly, Lactobacillus spp. significantly impaired C. jejuni adhesion in three-dimensional functional PSI cl.1 and B1OXI cell models. Also, C. jejuni did not translocate across PSI cl.1 and B1OXI cell monolayers when co-incubated with probiotics. Among selected probiotics, Lactobacillus rhamnosus LGG was the strain that reduced adhesion efficacy of C. jejuni most significantly under co-culture conditions. CONCLUSION: The addition of Lactobacillus spp. to feed additives in livestock nutrition might be an effective novel strategy that targets Campylobacter adhesion to epithelial cells, and thus prevents colonisation, reduces the transmission, and finally lowers the incidence of human campylobacteriosis.


Assuntos
Aderência Bacteriana , Translocação Bacteriana , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/fisiologia , Lactobacillus/fisiologia , Animais , Infecções por Campylobacter/fisiopatologia , Campylobacter jejuni/crescimento & desenvolvimento , Linhagem Celular , Galinhas , Células Epiteliais/microbiologia , Probióticos , Suínos
13.
Artigo em Inglês | MEDLINE | ID: mdl-31466273

RESUMO

The objective of this study was to survey health professionals to investigate their knowledge of probiotics. An online survey was conducted to gather data on the knowledge of health professionals. The online survey was distributed via email and social media platforms using snowball sampling. A total of 1066 health professionals (859; 80.6% female) from 30 countries responded to the survey. Most of the respondents evaluated their knowledge of probiotics as medium (36.4%) or good (36.2%). Only 8.9% of the respondents rated it as excellent. No statistical difference in knowledge was found between male and female health professionals. Over 80% of pharmacists, allied health professionals, medical doctors and dentists, and other health professionals knew the correct definition of probiotics as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host", whereas three quarters of registered nurses and midwives and less than two thirds of psychologists identified the correct definition. Statistically, more female than male health professionals knew the correct definition of probiotics. The most frequently recognized species of bacteria containing probiotic strains were Lactobacillus acidophilus (92%), Bifidobacterium bifidum (82%), and Lactobacillus rhamnosus (62%). The opinions on when it is best to take probiotics were different (χ2 = 28.375; p < 0.001), with 90.2% of respondents identifying that probiotics have beneficial effects if taken during antibiotic therapy, 83.5% for diarrhea, 70.6% for constipation, 63.3% before traveling abroad, and 60.4% for treating allergies. Almost 79% of health professionals involved in this study have advised their patients to use probiotics and 57.5% of the respondents wanted to learn more about probiotics. All things considered, health professionals have a medium level of knowledge of probiotics, which could be improved by the implementation of targeted learning programs. As probiotics have many beneficial effects in a wide range of health areas, health professionals need to adopt the use of probiotics in clinical practice.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Probióticos , Inquéritos e Questionários , Adulto , Idoso , Constipação Intestinal/terapia , Diarreia/terapia , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Mídias Sociais , Adulto Jovem
14.
Clin Nutr ; 38(3): 1373-1381, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29960810

RESUMO

BACKGROUND & AIMS: Celiac disease (CD) is an immune-mediated systemic disease, caused by ingestion of gluten in genetically predisposed individuals. Gut microbiota dysbiosis might play a significant role in pathogenesis of chronic enteropathies and its modulation can be used as an intervention strategy in CD as well. In this study, we aimed to identify correlations between fecal microbiota, serum tumor necrosis factor alpha (TNF-α) and fecal short-chain fatty acids (SCFAs) in healthy children and children with CD after administration of probiotic Bifidobacterium breve BR03 and B632. METHODS: A double-blind placebo-controlled study enrolled 40 children with CD (CD) and 16 healthy children (HC). CD children were randomly allocated into two groups, of which 20 belonged to the placebo (PL) group and 20 to the Probiotic (PR) group. The PR group received a probiotic formulation containing a mixture of 2 strains, B. breve BR03 (DSM 16604) and B. breve B632 (DSM 24706) in 1:1 ratio for 3 months. Subsequently, for statistical analysis, blood and fecal samples from CD children (on enrolment - T0 and after 3 months, at the end of intervention with probiotic/placebo - T1) and HC children were used. The HC group was sampled only once (T0). RESULTS: Verrucomicrobia, Parcubacteria and some yet unknown phyla of Bacteria and Archaea may be involved in the disease, indicated by a strong correlation to TNF-α. Likewise, Proteobacteria strongly correlated with fecal SCFAs concentration. The effect of probiotic administration has disclosed a negative correlation between Verrucomicrobia, some unknown phyla of Bacteria, Synergistetes, Euryarchaeota and some SCFAs, turning them into an important target in microbiome restoration process. Synergistetes and Euryarchaeota may have a role in the anti-inflammatory process in healthy human gut. CONCLUSIONS: Our results highlight new phyla, which may have an important relation to disease-related parameters, CD itself and health.


Assuntos
Bifidobacterium breve , Doença Celíaca/tratamento farmacológico , Doença Celíaca/metabolismo , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal , Probióticos/uso terapêutico , Fator de Necrose Tumoral alfa/sangue , Doença Celíaca/microbiologia , Criança , Método Duplo-Cego , Fezes/microbiologia , Feminino , Humanos , Masculino
15.
Biomed Res Int ; 2019: 7585486, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31915703

RESUMO

The skin and its microbiota serve as physical barriers to prevent invasion of pathogens. Skin damage can be a consequence of illness, surgery, and burns. The most effective wound management strategy is to prevent infections, promote healing, and prevent excess scarring. It is well established that probiotics can aid in skin healing by stimulating the production of immune cells, and they also exhibit antagonistic effects against pathogens via competitive exclusion of pathogens. Our aim was to conduct a review of recent literature on the efficacy of using probiotics against pathogens that cause wound infections. In this integrative review, we searched through the literature published in the international following databases: PubMed, ScienceDirect, Web of Science, and Scopus using the search terms "probiotic" AND "wound infection." During a comprehensive review and critique of the selected research, fourteen in vitro studies, 8 animal studies, and 19 clinical studies were found. Two of these in vitro studies also included animal studies, yielding a total of 39 articles for inclusion in the review. The most commonly used probiotics for all studies were well-known strains of the species Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, and Lactobacillus rhamnosus. All in vitro studies showed successful inhibition of chosen skin or wound pathogens by the selected probiotics. Within the animal studies on mice, rats, and rabbits, probiotics showed strong opportunities for counteracting wound infections. Most clinical studies showed slight or statistically significant lower incidence of surgical site infections, foot ulcer infection, or burn infections for patients using probiotics. Several of these studies also indicated a statistically significant wound healing effect for the probiotic groups. This review indicates that exogenous and oral application of probiotics has shown reduction in wound infections, especially when used as an adjuvant to antibiotic therapy, and therefore the potential use of probiotics in this field remains worthy of further studies, perhaps focused more on typical skin inhabitants as next-generation probiotics with high potential.


Assuntos
Antibacterianos/uso terapêutico , Lacticaseibacillus casei/fisiologia , Lactobacillus acidophilus/fisiologia , Lactobacillus plantarum/fisiologia , Probióticos/uso terapêutico , Infecção dos Ferimentos/prevenção & controle , Animais , Quimioterapia Adjuvante , Cicatriz/prevenção & controle , Humanos , Camundongos , Coelhos , Ratos , Cicatrização
16.
Biomed Pharmacother ; 94: 1176-1185, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28830068

RESUMO

Over the past decade, it has become clear that specific probiotic lactobacilli are valuable in the prevention and treatment of infectious and inflammatory diseases of gastrointestinal tract but their successful application would benefit greatly from a better understanding of the mechanisms of individual strains. Hence, each probiotic strain should be characterized for their immune activity before being proposed for clinical applications. The aim of the study was to characterize the immunomodulatory activity of the strain Lactobacillus (L.) plantarum LS/07 in vitro using functional gut model and to study its anti-inflammatory potential in dextran sulphate sodium (DSS)-induced colitis in rats. We showed that L. plantarum LS/07 induced production of IL-10 in macrophages derived from blood monocytes as well as monocyte/macrophages cell line stimulated indirectly via enterocytes in vitro. In rat model of colitis, L. plantarum LS/07 attenuated the DSS-induced signs of inflammatory process in colon such as weight loss, diarrhoea, infiltration of inflammatory cells associated with decreased colon weight/length ratio, inhibited gut mucosa destruction and depletion of goblet cells. Moreover, the strain increased the concentration of anti-inflammatory cytokine IL-10 in mucosal tissue. In conclusion, the protective effects of L. plantarum LS/07 in the DSS-induced colitis model seem to be related to the stimulation of IL-10 and the restoration of goblet cells and indicate it as a good candidate to prevent and treat diseases associated with inflammation.


Assuntos
Colite/tratamento farmacológico , Citocinas/metabolismo , Lactobacillus plantarum/fisiologia , Probióticos/farmacologia , Adulto , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Colite/induzido quimicamente , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-10/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Lactobacillus plantarum/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Food Chem Toxicol ; 104: 14-25, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28286311

RESUMO

This work aims at deepening the understanding of the mode of action of some of the most prominent perfluorinated compounds (PFCs) by detecting in a realistic way their effects. To this end, after adjusting the exposure media taking into account the biological model employed and the physico-chemical properties of PFCs, we evaluated the toxic effects of PFOA, PFOS and PFNA in a human macrophage cell line (TLT cells) and in zebrafish embryos. We performed such evaluation on individual compounds and mixtures. Acute toxicity was greater for PFOS in zebrafish; however, it was greater for PFNA in TLT cells. PFNA was also the compound producing the greatest levels of oxidative stress, both in zebrafish and TLT cells. Additionally, in both biological systems, it showed a much stronger effect on mixtures in comparison to the others PFCs tested in this work. Mixture studies in zebrafish showed that acute toxicity depended on the concentration and that the mixture was far more toxic than the individual compounds. This study highlights the importance of studying PFCs in realistic conditions on various biological models.


Assuntos
Fluorocarbonos/toxicidade , Macrófagos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular , Fluorocarbonos/análise , Humanos , Macrófagos/metabolismo , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/análise , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
18.
Food Res Int ; 94: 45-53, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28290366

RESUMO

Malabsorption of dietary sugars is a common cause of gastrointestinal discomfort, affecting up to one in three people with debilitating symptoms, such as abdominal pain, osmotic diarrhoea, bloating and flatulence. Besides dietary interventions, it has been suggested that ingestion of lactobacilli may alleviate these symptoms. The objectives of this study were to generate strains with improved potential to ameliorate sugar malabsorption related gastrointestinal disorders. Initial selection was made from 183 natural isolates of lactic acid bacteria, on the basis of broad sugar fermentation ability, absence of gas production, gastrointestinal survival and susceptibility to important medical antimicrobials. Two strains of L. plantarum (KR6 and M5) exhibited favourable characteristics for all criteria, and were further optimised through random mutagenesis and selection approaches. Ultraviolet light (UV) exposure resulted in mutants characterized by better survival (for 1.9 log and 1.4 log) in gastrointestinal conditions. Subsequent exposure to ethyl methanesulfonate (EMS) provided mutants with greater tolerance to glucose induced catabolic repression. UV and UV-EMS mutants of L. plantarum M5 showed improved adhesion ability. As a result of this optimisation, L. plantarum MP2026 and L. plantarum MP2420 have been identified as promising candidates for probiotics, intended for alleviation of gastrointestinal discomfort originating from sugar malabsorption.


Assuntos
Açúcares da Dieta/metabolismo , Gastroenteropatias/microbiologia , Intestinos/microbiologia , Lactobacillus plantarum , Síndromes de Malabsorção/complicações , Probióticos , Dor Abdominal/etiologia , Dor Abdominal/microbiologia , Dor Abdominal/prevenção & controle , Aderência Bacteriana , Metabolismo dos Carboidratos , Linhagem Celular , Fermentação , Flatulência , Gastroenteropatias/etiologia , Gastroenteropatias/prevenção & controle , Glucose/metabolismo , Humanos , Absorção Intestinal , Intestinos/citologia , Lactobacillus plantarum/genética , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/isolamento & purificação , Mutagênese , Mutação , Especificidade da Espécie
19.
Anal Biochem ; 526: 9-21, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28300535

RESUMO

Short-chain fatty acids (SCFAs) play a crucial role in maintaining homeostasis in humans, therefore the importance of a good and reliable SCFAs analytical detection has raised a lot in the past few years. The aim of this scoping review is to show the trends in the development of different methods of SCFAs analysis in feces, based on the literature published in the last eleven years in all major indexing databases. The search criteria included analytical quantification techniques of SCFAs in different human clinical and in vivo studies. SCFAs analysis is still predominantly performed using gas chromatography (GC), followed by high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) and capillary electrophoresis (CE). Performances, drawbacks and advantages of these methods are discussed, especially in the light of choosing a proper pretreatment, as feces is a complex biological material. Further optimization to develop a simple, cost effective and robust method for routine use is needed.


Assuntos
Ácidos Graxos Voláteis/análise , Fezes/química , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humanos
20.
Nutrients ; 8(10)2016 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-27782071

RESUMO

Coeliac disease (CD) is associated with alterations of the intestinal microbiota. Although several Bifidobacterium strains showed anti-inflammatory activity and prevention of toxic gliadin peptides generation in vitro, few data are available on their efficacy when administered to CD subjects. This study evaluated the effect of administration for three months of a food supplement based on two Bifidobacterium breve strains (B632 and BR03) to restore the gut microbial balance in coeliac children on a gluten free diet (GFD). Microbial DNA was extracted from faeces of 40 coeliac children before and after probiotic or placebo administration and 16 healthy children (Control group). Sequencing of the amplified V3-V4 hypervariable region of 16S rRNA gene as well as qPCR of Bidobacterium spp., Lactobacillus spp., Bacteroides fragilis group Clostridiumsensu stricto and enterobacteria were performed. The comparison between CD subjects and Control group revealed an alteration in the intestinal microbial composition of coeliacs mainly characterized by a reduction of the Firmicutes/Bacteroidetes ratio, of Actinobacteria and Euryarchaeota. Regarding the effects of the probiotic, an increase of Actinobacteria was found as well as a re-establishment of the physiological Firmicutes/Bacteroidetes ratio. Therefore, a three-month administration of B. breve strains helps in restoring the healthy percentage of main microbial components.


Assuntos
Bifidobacterium breve , Doença Celíaca/terapia , Suplementos Nutricionais , Microbioma Gastrointestinal/fisiologia , Probióticos/administração & dosagem , Actinobacteria , Adolescente , Bacteroidetes , Doença Celíaca/microbiologia , Criança , Pré-Escolar , Terapia Combinada , DNA Bacteriano/análise , Dieta Livre de Glúten , Método Duplo-Cego , Fezes/microbiologia , Feminino , Firmicutes , Humanos , Lactente , Masculino , Projetos Piloto , RNA Ribossômico 16S/análise , Adulto Jovem
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