A Mixture of Four Probiotic Strains (Probiatop®) Mitigates Food Allergy to Ovalbumin in Mice.

Food allergy is a pathological condition caused by a disruption of oral tolerance. This condition leads to a pro-inflammatory environment that culminates in symptoms that varies from abdominal pain to anaphylaxis and death. The gold standard treatment consists of removing the food that triggers the allergy from diet. However, this conduct can cause nutritional impairment and social restrictions. Therefore, the need for new treatment strategies is notorious. In this context, probiotics are investigated due to their immunomodulatory mechanisms. Therefore, the objective of the present work is to investigate the probiotic potential of a mixture of four probiotic strains (Probiatop®) in an in vivo model of food allergy to ovalbumin (OVA). Our results demonstrated that oral administration of Probiatop® attenuated weight loss and diminished significantly anti-OVA IgE and IgG1 levels. Furthermore, it mitigated proximal jejunum injury, neutrophil recruitment and local IL17 levels. In addition, the probiotic mixture modulated positively the gut microbiota composition by decreasing the levels and frequency of Staphylococcus and yeast. In summary, our data suggest that Probiatop® has the potential to alleviate important symptoms of IgE-mediated food allergy, suggesting its probiotic potential as an adjuvant in the treatment of ovalbumin food allergy.

Oral Treatment with Saccharomyces cerevisiae CNCM I-3856 Mitigates the Inflammatory Response Experimentally Induced by Salmonella enterica subsp. enterica Serovar Typhimurium in Mice.

Salmonella spp. are intracellular, Gram-negative pathogens responsible for a range of diarrheal diseases, which can present either as self-limited (gastroenteritis) or as a systemic form (typhoid fever), characterizing a serious public health problem. In this study, we investigated the therapeutic effects of oral administration of Saccharomyces cerevisiae CNCM I-3856 in a murine model infected with Salmonella Typhimurium (ST). This yeast species has previously demonstrated the potential to support immune function and reduce inflammation and the ability to exert antimicrobial activity, which is important considering the increasing prevalence of antibiotic-resistant bacteria. Our findings revealed that mice infected with ST and only treated with sterile saline exhibited a higher mortality rate and body weight loss. In contrast, mice treated with I-3856 showed a notable reduction in these adverse outcomes. The yeast demonstrated a high capacity for co-aggregation with the pathogen. Furthermore, the significant amounts of yeast found in the feces of treated mice suggest that intestinal colonization was effective, which was associated with several beneficial effects, including reduced intestinal permeability, which likely limits bacterial translocation to extraintestinal organs. Additionally, the administration of I-3856 reduced levels of sIgA and resulted in a decrease in the recruitment of neutrophils and eosinophils to infection sites, indicating a modulation of the inflammatory response. Histological analyses showed attenuated liver and intestinal lesions in the yeast-treated mice, corroborating the protective effects of the yeast. In conclusion, the results suggest that S. cerevisiae CNCM I-3856 has the potential to control the inflammatory response experimentally induced by S. Typhimurium when administered to mice.

A Functional Bread Fermented with Saccharomyces cerevisiae UFMG A-905 Prevents Allergic Asthma in Mice.

Background: The administration of probiotics has been shown to be beneficial in asthma. The administration of Saccharomyces cerevisiae UFMG A-905 prevented asthma development. Traditionally, probiotics are administered using dairy-based matrices, but other vehicles (e.g., fruit juices, biscuits, candies, and breads) can be used. Objectives: This study aimed to assess the effect of bread fermented with S. cerevisiae UFMG A-905 in asthma prevention. Methods: Three breads were produced: fermented with commercial yeast, fermented with S. cerevisiae UFMG A-905, and fermented with S. cerevisiae UFMG A-905 with the addition of alginate microcapsules containing live S. cerevisiae UFMG A-905. Characterization of the microbial composition of the breads was performed. Male Balb/c mice were sensitized and challenged with ovalbumin. Breads were administered 10 d before the first sensitization and during sensitization and challenge protocol. Yeast fecal count, in vivo airway hyperresponsiveness, and airway and lung inflammation were assessed. Results: In UFMG A-905 bread, there was an increase in yeast number and a decrease in total and lactic acid bacteria. Animals that received S. cerevisiae UFMG A-905 fermented bread with microcapsules had a significant increase in yeast recovery from feces. S. cerevisiae UFMG A-905-fermented breads partially reduced airway inflammation, decreasing eosinophils and IL5 and IL13 concentrations. When adding microcapsules, the bread also diminished airway hyperresponsiveness and increased IL17A concentrations. Conclusions: S. cerevisiae UFMG A-905 was able to generate long-fermentation breads. Microcapsules were a safe and viable way to inoculate the live yeast into food. The administration of breads fermented with S. cerevisiae UFMG A-905 prevented asthma-like characteristics, being more pronounced when the breads contained microcapsules with live yeast.

Evaluation of the Treatment with Akkermansia muciniphila BAA-835 of Chemotherapy-induced Mucositis in Mice.

Mucositis is a high-incidence side effect in cancer patients undergoing chemotherapy. Next-generation probiotics are emerging as new therapeutic tools for managing various disorders. Studies have demonstrated the potential of Akkermansia muciniphila to increase the efficiency of anticancer treatment and to mitigate mucositis. Due to the beneficial effect of A. muciniphila on the host, we evaluated the dose-response, the microorganism viability, and the treatment protocol of A. muciniphila BAA-835 in a murine model of chemotherapy-induced mucositis. Female Balb/c mice were divided into groups that received either sterile 0.9% saline or A. muciniphila by gavage. Mucositis was induced using a single intraperitoneal injection of 5-fluorouracil. The animals were euthanized three days after the induction of mucositis, and tissue and blood were collected for analysis. Prevention of weight loss and small intestine shortening and reduction of neutrophil and eosinophil influx were observed when animals were pretreated with viable A. muciniphila at 1010 colony-forming units per mL (CFU/mL). The A. muciniphila improved mucosal damage by preserving tissue architecture and increasing villus height and goblet cell number. It also improved the integrity of the epithelial barrier, decreasing intestinal permeability and bacterial translocation. In addition, the treatment prevented the expansion of Enterobacteriaceae. The immunological parameters were also improved by decreasing the expression of pro-inflammatory cytokines (IL6, IL1ß, and TNF) and increasing IL10. In conclusion, pretreatment with 1010 CFU/mL of viable A. muciniphila effectively controlled inflammation, protected the intestinal mucosa and the epithelial barrier, and prevented Enterobacteriaceae expansion in treated mice.

Comparative metatranscriptome analysis of Brazilian milk and water kefir beverages.

The present study compared bacterial and fungal diversity of kefir beverages produced using milk (MK) or sugared water (WK) as propagation matrices and grains from the cities of Curitiba (CU) or Salvador (SA), Brazil, by sequencing the complete set of RNA transcripts produced in four products. In Brazil, milk and sugared water are used as matrices to propagate kefir grains. In all beverages, the bacterial community was composed of Lactobacillaceae and Acetobacteraceae. Saccharomycetaceae was the yeast family more abundant in WK, and Dipodascaceae and Pichiaceae in MK. Regarding KEGG mapping of functional orthologs, the four kefir samples shared 70% of KO entries of yeast genes but only 36% of bacterial genes. Concerning main metabolic processes, the relative abundance of transcripts associated with metabolism (energy metabolism) and environmental information processing (membrane transport) had the highest water/milk kefir ratio observed in Firmicutes. In contrast, transcripts associated with genetic information processing (protein translation, folding, sorting, and degradation) oppositely had the lowest water/milk ratios. Concluding, milk and water kefir have quite different communities of microorganisms. Still, the main mapped functional processes are similar, with only quantitative variation in membrane transport and energy acquisition in the water kefir and protein synthesis and turnover in the milk kefir.

A Next-Generation Bacteria (Akkermansia muciniphila BAA-835) Presents Probiotic Potential Against Ovalbumin-Induced Food Allergy in Mice.

Next-generation microorganisms have recently gained prominence in the scientific community, mainly due to their probiotic and postbiotic potentials. However, there are few studies that investigate these potentials in food allergy models. Therefore, the present study was designed to evaluate the probiotic potential of Akkermansia muciniphila BAA-835 in an ovalbumin food allergy (OVA) model and also analyse possible postbiotic potential. To access the probiotic potential, clinical, immunological, microbiological, and histological parameters were evaluated. In addition, the postbiotic potential was also evaluated by immunological parameters. Treatment with viable A. muciniphila was able to mitigate weight loss and serum levels of IgE and IgG1 anti-OVA in allergic mice. In addition, the ability of the bacteria to reduce the injury of the proximal jejunum, the eosinophil and neutrophil influx, and the levels of eotaxin-1, CXCL1/KC, IL4, IL6, IL9, IL13, IL17, and TNF, was clear. Furthermore, A. muciniphila was able to attenuate dysbiotic signs of food allergy by mitigating Staphylococcus levels and yeast frequency in the gut microbiota. In addition, the administration of the inactivated bacteria attenuated the levels of IgE anti-OVA and eosinophils, indicating its postbiotic effect. Our data demonstrate for the first time that the oral administration of viable and inactivated A. muciniphila BAA-835 promotes a systemic immunomodulatory protective effect in an in vivo model of food allergy to ovalbumin, which suggests its probiotic and postbiotic properties.

Evaluation of a Functional Craft Wheat Beer Fermented with Saccharomyces cerevisiae UFMG A-905 to treat Salmonella Typhimurium infection in mice.

Functional foods containing probiotics are generally administered as dairy products. Non-dairy beverages are another possibility, but probiotic functionality must be confirmed in such vehicles. In the present study, a craft wheat beer brewed with the probiotic yeast Saccharomyces cerevisiae UFMG A-905 (905) was evaluated in a murine model of Salmonella Typhimurium infection. Unfiltered or filtered beer brewed with 905, a commercial wheat beer used as a negative control, or saline were administered orally to mice before and during oral S. Typhimurium challenge. High fecal levels of yeast were only counted in mice treated with the unfiltered 905 beer, which also had reduced mortality and body weight loss due to S. Typhimurium infection. Increased levels of intestinal IgA, translocation to liver and spleen, liver and intestinal lesions, pro-inflammatory cytokines in liver and ileum, and hepatic and intestinal myeloperoxidase and eosinophilic peroxidase activities were observed in animals infected with S. Typhimurium. All these parameters were reduced by the treatment with unfiltered 905 beer. In conclusion, the results show that a craft wheat beer brewed with S. cerevisiae UFMG A-905 maintained the probiotic properties of this yeast when administered orally to mice challenged with S. Typhimurium.

Isolation and Identification of Potential Probiotic Bacteria from Human Milk.

Breast milk was long considered a sterile environment, but now it is known to harbor many bacteria that will shape the newborn microbiota. The benefits of breastfeeding to newborn health are, on some level, related to the presence of beneficial bacteria in human milk. Therefore, this study aims to investigate and isolate potential probiotics present in human milk that might be associated with improved health in infants, being potential candidates to be used in simulated human milk formula. Milk samples of 24 healthy mothers were collected at three time points: 30 min (colostrum), 5-9 days (transitional milk), and 25-30 days (mature milk) postpartum. Samples were evaluated by culturing, and the isolated bacteria were identified by MALDI-TOF MS and 16S DNA sequencing. In vitro screening for probiotics properties was performed, and the potential probiotics were mono-associated with germ-free mice to evaluate their ability to colonize the gastrointestinal tract. The microorganisms were submitted to the spray-drying process to check their viability for a potential simulated milk formula production. Seventy-seven bacteria were isolated from breast milk pertaining to four bacterial genera (Staphylococcus, Streptococcus, Leuconostoc, and Lacticaseibacillus). Four potential probiotics were selected: Lacticaseibacillus rhamnosus (n = 2) and Leuconostoc mesenteroides (n = 2). Isolates were able to colonize the gastrointestinal tract of germ-free mice and remained viable after the spray-drying process. In conclusion, breast milk harbors a unique microbiota with beneficial microorganisms that will impact the newborn gut colonization, being an essential source of probiotic candidates to be used in a formula of simulated maternal milk.

Bifidobacterium longum subsp. longum 51A Attenuates Signs of Inflammation in a Murine Model of Food Allergy.

Food allergy is a pathological condition that can lead to hives, swelling, gastrointestinal distress, cardiovascular and respiratory compromise, and even anaphylaxis. The lack of treatment resources emphasizes the necessity for new therapeutic strategies, and in this way, probiotics has been pointed out as an alternative, especially because of its immunomodulatory properties. The goal of this study was to evaluate the probiotic effect of Bifidobacterium longum subsp. longum 51A (BL51A) in a murine model of ovalbumin (OVA) food allergy, as well as to investigate the effect of the dose and viability of the bacteria on the proposed model. For this purpose, the probiotic effect was assessed by clinical, immunological, and histological parameters in mice treated or not with the BL51A and sensitized or not with OVA. Oral administration of BL51A prevented weight loss and reduced serum levels of IgE anti-OVA and of sIgA in the intestinal fluid. Also, it reduced the intestinal permeability, proximal jejunum damage, recruitment of eosinophils and neutrophils, and levels of eotaxin-1, CXCL1/KC, IL4, IL5, IL6, IL13, and TNF. Furthermore, the treatment was able to increase the levels of IL10. Investigating different doses administered, the level of 108 CFU showed the best results in terms of protective effect. In addition, the administration of the inactivated bacteria did not present any beneficial effect. Results demonstrate that BL51A promotes a systemic immunomodulatory protective effect in a murine model of food allergy that depends on the dose and viability of the bacteria, suggesting its use as probiotic in such disease.

Changes in bovine milk bacterial microbiome from healthy and subclinical mastitis affected animals of the Girolando, Gyr, Guzera, and Holstein breeds.

Raw milk samples were collected from 200 dairy cows belonging to Girolando 1/2, Gyr, Guzera, and Holstein breeds, and the bacterial diversity was explored using 16S rRNA amplicon sequencing. SCC analysis showed that 69 animals were classified as affected with subclinical mastitis. The milk bacterial microbiome was dominated by Firmicutes, Proteobacteria, and Actinobacteria, with an increase of Firmicutes in animals with subclinical mastitis and Proteobacteria in healthy animals. At the family and genus level, the milk bacterial microbiome was dominated by Staphylococcus, Acinetobacter, Pseudomonas, members of the family Enterobacteriaceae, Lactococcus, Aerococcus, members of the family Rhizobiaceae, Anaerobacillus, Streptococcus, members of the family Intrasporangiaceae, members of the family Planococcaceae, Corynebacterium, Nocardioides, and Chryseobacterium. Significant differences in alpha and beta diversity analysis suggest an effect of udder health status and breed on the composition of raw bovine milk microbiota. LEfSe analysis showed 45 and 51 discriminative taxonomic biomarkers associated with udder health status and with one of the four breeds respectively, suggesting an effect of subclinical mastitis and breed on the microbiota of milk in cattle.

Bifidobacterium longum subsp. longum 51A attenuates intestinal injury against irinotecan-induced mucositis in mice.

Intestinal mucositis (IM) is a critical side-effect associated with antineoplastic therapy. Treatment available is only palliative and often not effective. However, alternative therapeutic strategies, such as probiotics, have attracted significant attention due to their immune-modulatory action in several diseases. Thus, the present study aims to elucidate the therapeutic potential of the probiotic strain Bifidobacterium longum 51A in a murine model of mucositis induced by irinotecan. Due to the scarcity of studies on dose-response and viability (probiotic vs paraprobiotic), we first evaluated which dose and cell viability would be most effective in treating mucositis. In this study, the oral pretreatment with viable B. longum 51A at a concentration of 1 × 109 CFU/mL reduced the daily disease activity index (p < 0.01), protected the intestinal architecture, preserved the length of the intestine (p < 0.05), and reduced intestinal permeability (p < 0.01), inflammation, and oxidative damage (p < 0.01) induced by irinotecan. Also, treatment with B. longum 51A increased the production of secretory immunoglobulin A (p < 0.05) in the intestinal fluid of mice with mucositis. Furthermore, B. longum 51A reversed the mucositis-induced increase in Enterobacteriaceae bacterial group in the gut (p < 0.01). In conclusion, these results showed that oral administration of B. longum 51A protects mice against intestinal damage caused by irinotecan, suggesting its use as a potential probiotic in therapy during mucositis.

Prospecting of potentially probiotic lactic acid bacteria from bovine mammary ecosystem: imminent partners from bacteriotherapy against bovine mastitis.

Mastitis is one of the most important causes of loss of cattle production, burdening producers due to the increased cost of milk production and decreased herd productivity. The development of alternative methods for the treatment and prevention of mastitis other than traditional chemical antibiotic therapy needs to be implemented to meet international pressures to reduce the use of these drugs and promote the elimination of multiresistant microbial strains from the environment. Treatment with probiotic bacteria or yeast strains offers a possible strategy for the control of mastitis. The objective of this work was to isolate, identify, and characterize lactic bacteria from milk and the intramammary duct of Gyr, Guzerat, Girolando 1/2, and Holstein cattle breeds from Brazil. Samples of 115 cows were taken, a total of 192 bacteria isolates belonging to 30 species were obtained, and 81 were selected to evaluate their probiotic potential in in vitro characterization tests. In general, bacteria isolated from the mammary gland have low autoaggregation, cell surface hydrophobicity, and co-aggregation with mastitis etiological bacteria Staphylococcus aureus and Escherichia coli. Also, they have biofilm assembly capacity, inability to produce exopolysaccharides, high production of H2O2, and strong antagonism against mastitis pathogens. Ten lactic bacteria isolates were used in co-culture with human MDA-MB-231 breast epithelial cells to assess their adhesion capacity and impairment of the S. aureus invasion. Our results, therefore, contribute to the future production of new prevention and treatment tools for bovine mastitis.

Antarctic Strain of Rhodotorula mucilaginosa UFMGCB 18,377 Attenuates Mucositis Induced by 5-Fluorouracil in Mice.

Mucositis is one of the most strenuous side effects caused by chemotherapy drugs, such as 5-fluorouracil (5-FU), during the treatment of several types of cancers. The disease is so prevalent and aggressive that many patients cannot resist such symptoms. However, despite its frequency and clinical significance, there is no effective treatment to prevent or treat mucositis. Thus, the use of probiotics as an adjuvant for the treatment has gained prominence. In the present study, we evaluated the effectiveness of oral administration of the Antarctic strain of Rhodotorula mucilaginosa UFMGCB 18,377 as an alternative to minimize side effects of 5-FU-induced mucositis in mice. Body weight, food consumption, stool consistency, and presence of blood in the feces were assessed daily in mice orally treated or not with the yeast and submitted or not to experimental mucositis. Blood, bones, and intestinal tissues and fluid were used to determine intestinal permeability and immunological, microbiological, and histopathological parameters. Treatment with R. mucilaginosa UFMGCB 18,377 was able to decrease clinical signs of the disease, such as reduction of food intake and body weight loss, and also decreased the number of intestinal enterobacteria and intestinal length shortening. Additionally, treatment was able to decrease the levels of MPO and EPO activities and inflammatory infiltrates, as well as the histopathological lesions characteristic of mucositis in the jejunum and ileum. Results of the present study showed that the oral administration of R. mucilaginosa UFMGCB 18,377 protected mice against mucositis induced by 5-FU.

Sex differences in the development of conditioned place preference induced by intragastric alcohol administration in mice.

BACKGROUND: The present study aimed to identify for the first time sex differences in the development of CPP induced by intragastric alcohol administration in mice. METHODS: Male and female adult Swiss mice were submitted to 16 days of conditioning with alcohol (0.5-3.0 g/kg, N = 8/dose/sex), with 2 post-conditioning tests (after 8 and 16 sessions) during the protocol. RESULTS: 8 days of conditioning (4 alcohol sessions, 4 saline sessions) with intragastric alcohol administration were sufficient to induce CPP in male mice at the doses of 1.0, 1.5 and 2.0 g/kg. However, only higher doses (2.0, 2.5 and 3.0 g/kg) induced CPP in female mice using an 8-day conditioning protocol, while a 16-day conditioning protocol was necessary for the development of intragastric alcohol-induced CPP at the doses of 1.0 and 1.5 g/kg. Regardless of the conditioning protocol, higher doses or alcohol that had rewarding effects in females (2.5 and 3.0 g/kg) did not induce CPP in males, with a significant difference between males and females at those doses. Analysis of the potency (EC50) and efficacy (Emax) of alcohol in inducing CPP when administered intragastrically in male and female mice showed significant sex differences with 8 conditioning sessions. CONCLUSIONS: Our data show a clear protocol (8 vs 16 days) and dose difference between male and female Swiss mice regarding the development of CPP induced by intragastric alcohol administration. Intragastric alcohol administration is closer to human drinking, and our protocol provides a more translational approach to studying the rewarding effects of alcohol in mice.

Bifidobacterium Strains Present Distinct Effects on the Control of Alveolar Bone Loss in a Periodontitis Experimental Model.

Periodontitis is an inflammatory disease induced by a dysbiotic oral microbiome. Probiotics of the genus Bifidobacterium may restore the symbiotic microbiome and modulate the immune response, leading to periodontitis control. We evaluated the effect of two strains of Bifidobacterium able to inhibit Porphyromonas gingivalis interaction with host cells and biofilm formation, but with distinct immunomodulatory properties, in a mice periodontitis model. Experimental periodontitis (P+) was induced in C57Bl/6 mice by a microbial consortium of human oral organisms. B. bifidum 1622A [B+ (1622)] and B. breve 1101A [B+ (1101)] were orally inoculated for 45 days. Alveolar bone loss and inflammatory response in gingival tissues were determined. The microbial consortium induced alveolar bone loss in positive control (P + B-), as demonstrated by microtomography analysis, although P. gingivalis was undetected in oral biofilms at the end of the experimental period. TNF-α and IL-10 serum levels, and Treg and Th17 populations in gingiva of SHAM and P + B- groups did not differ. B. bifidum 1622A, but not B. breve 1101A, controlled bone destruction in P+ mice. B. breve 1101A upregulated transcription of Il-1ß, Tnf-α, Tlr2, Tlr4, and Nlrp3 in P-B+(1101), which was attenuated by the microbial consortium [P + B+(1101)]. All treatments downregulated transcription of Il-17, although treatment with B. breve 1101A did not yield such low levels of transcripts as seen for the other groups. B. breve 1101A increased Th17 population in gingival tissues [P-B+ (1101) and P + B+ (1101)] compared to SHAM and P + B-. Administration of both bifidobacteria resulted in serum IL-10 decreased levels. Our data indicated that the beneficial effect of Bifidobacterium is not a common trait of this genus, since B. breve 1101A induced an inflammatory profile in gingival tissues and did not prevent alveolar bone loss. However, the properties of B. bifidum 1622A suggest its potential to control periodontitis.

Probiotics improve re-epithelialization of scratches infected by Porphyromonas gingivalis through up-regulating CXCL8-CXCR1/CXCR2 axis.

Porphyromonas gingivalis inhibits the release of CXCL8 by gingival epithelial cells and reduces their proliferation. We previously reported that Bifidocaterium sp. and Lactobacillus sp. immunomodulate gingival epithelial cells response to this periodontal pathogen, but their effects on re-epithelialization properties are still unknown. Herein we explored these activities of potential probiotics on gingival epithelial cells and clarified their mechanisms. The immortalized OBA-9 lineage was used to perform in vitro scratches. Twelve clinical isolates and commercially available strains of Bifidobacterium sp. and Lactobacillus sp. were screened. L. casei 324 m and B. pseudolongum 1191A were selected to perform mechanistic assays with P. gingivalis W83 infection and the following parameters were measured: percentage of re-epithelialization by DAPI immunofluorescence area measurement; cell number by Trypan Blue exclusion assay; CXCL8 regulation by ELISA and RT-qPCR; and expression of CXCL8 cognate receptors-CXCR1 and CXCR2 by Flow Cytometry. Complementary mechanistic assays were performed with CXCL8, in the presence or absence of the CXCR1/CXCR2 inhibitor-reparixin. L. casei 324 m and B. pseudolongum 1191A enhanced re-epithelialization/cell proliferation as well as inhibited the harmful effects of P. gingivalis W83 on these activities through an increase in the expression and release of CXCL8 and in the number of cells positive for CXCR1/CXCR2. Further, we revealed that the beneficial effects of these potential probiotics were dependent on activation of the CXCL8-CXCR1/CXCR2 axis. The current findings indicate that these potential probiotics strains may improve wound healing in the context of the periodontal tissues by a CXCL8 dependent mechanism.

Comparative genomics and in silico gene evaluation involved in the probiotic potential of Bifidobacterium longum 51A.

The Bifidobacterium longum 51A strain of isolated from feces of a healthy child, has demonstrated probiotic properties by in vivo and in vitro studies, which may be assigned to its production of metabolites such as acetate. Thus, through the study of comparative genomics, the present work sought to identify unique genes that might be related to the production of acetate. To perform the study, the DNA strain was sequenced using Illumina HiSeq technology, followed by assembly and manual curation of coding sequences. Comparative analysis was performed including 19 complete B. longum genomes available in Genbank/NCBI. In the phylogenetic analysis, the CECT 7210 and 157F strains of B. longum subsp. infantis aggregated within the subsp. longum cluster, suggesting that their taxonomic classification should be reviewed. The strain 51A of B. longum has 26 unique genes, six of which are possibly related to carbohydrate metabolism and acetate production. The phosphoketolase pathway from B. longum 51A showed a difference in acetyl-phosphate production. This result seems to corroborate the analysis of their unique genes, whose presence suggests the strain may use different sources of carbohydrates that allow a greater production of acetate and consequently offer benefits to the host health.

In Vitro and In Vivo Evaluation of the Probiotic Potential of Antarctic Yeasts.

Antarctica is one of the most pristine and inhospitable regions of the planet, mostly inhabited by microorganisms that survive due to unusual metabolic pathways to adapt to its extreme conditions, which could be interesting for the selection of new probiotics. The aim of the present study was to screen in vitro and in vivo putative probiotics among 254 yeasts isolated from different habitats of Antarctica. In vitro selection evaluated functional (growth at 37 °C, resistance to simulated gastric environment, and to bile salts), safety (degradation of mucin, production of ß-haemolysis and resistance to antifungal drugs), and beneficial (production of antagonistic substances and adhesion to pathogens) properties. Twelve yeasts were able to grow at 37 °C, one of which was eliminated to present ß-haemolytic ability. The remained yeasts resisted to gastric simulation and bile salts, but none presented antagonism against the pathogens tested. Because of the high co-aggregation with Salmonella enterica Typhimurium and growth yield, Rhodotorula mucilaginosa UFMGCB 18377 and Saccharomyces cerevisiae UFMGCB 11120 were selected for in vivo steps using mice challenged with S. Typhimurium. Both yeasts reached high faecal population levels when daily administered, but only R. mucilaginosa UFMGCB 18377 protected mice against Salmonella infection presenting a higher survival and reduced weight loss, bacterial translocation to the liver, sIgA intestinal levels, and intestinal and hepatic MPO and EPO activities. Our in vitro and in vivo results suggest that R. mucilaginosa UFMGCB 18377 presents probiotic potential and deserve further studies as candidate of probiotic by-products. In addition, this is the first screening study of yeasts isolated from Antarctic environments and of Rhodotorula genus for probiotic use.

Lactobacillus rhamnosus CGMCC 1.3724 (LPR) Improves Skin Wound Healing and Reduces Scar Formation in Mice.

Skin wounds are an important clinical problem which affects millions of people worldwide. The search for new therapeutic approaches to improve wound healing is needed. The present study aimed to evaluate the effects of the oral treatment with the skin-related probiotics Lactobacillus johnsonii LA1 (LJ), L. paracasei ST11 (LP), and L. rhamnosus LPR (LR) in a model of excisional skin wounds in Swiss mice. The animals received daily oral gavage of PBS or 1 × 107 colony-forming units of LJ, LP, or LR, singly, beginning just after the creation of wounds until euthanasia. Blood flow was evaluated by laser Doppler perfusion imaging. Myeloperoxidase and N-acetyl-ß-D-glucosaminidase activities were used to assess the accumulation of neutrophils and macrophages, respectively. The wound tissue was also collected for histological analyses (H&E, Toluidine blue, and Picrosirius red staining). The macroscopic wound closure rate was faster only in mice treated with LR, but not with LJ and LP, when compared to mice treated with PBS. Histological evaluations showed that treatment with LR stimulated wound epithelization when compared to PBS. Further analyses showed that wounds from LR-treated mice presented a significant decrease in macrophage (p < 0.001) and mast cell (p < 0.001) infiltration, along with improved angiogenesis (p < 0.001) and blood flow (p < 0.01). Of note, collagen deposition and scarring were reduced in LR-treated mice when compared to PBS-treated mice. In conclusion, our results show that the oral treatment with Lactobacillus rhamnosus accelerates skin wound closure and reduces scar, besides to reducing inflammation and fibrogenesis and improving angiogenesis in the wounded skin.

Impact of vitamin deficiency on microbiota composition and immunomodulation: relevance to autistic spectrum disorders.

OBJECTIVES: Inappropriate vitamin supply is a public health problem and is related to abnormalities in brain development, immune response and, more recently, in changes of gut microbial composition. It is known that low levels of vitamin in early life are linked to increased susceptibility to neurodevelopmental disorders, such as Autism Spectrum Disorders (ASD). Unfortunately, the possible peripheral influences of vitamin deficiency that leads to alterations in the gut microbiota-immune-brain axis, one important modulator of the ASD pathology, remain unclear. This narrative review discusses how the impact of vitamin deficiency results in changes in the immune regulation and in the gut microbiota composition, trying to understand how these changes may contribute for the development and severity of ASD. METHODS: The papers were selected using Pubmed and other databases. This review discusses the following topics: (1) vitamin deficiency in alterations of central nervous system in autism, (2) the impact of low levels of vitamins in immunomodulation and how it can favor imbalance in gut microbiota composition and gastrointestinal (GI) disturbances, (3) gut microbiota imbalance/inflammation associated with the ASD pathophysiology, and (4) possible evidences of the role of vitamin deficiency in dysfunctional gut microbiota-immune-brain axis in ASD. RESULTS: Studies indicate that hypovitaminosis A, B12, D, and K have been co-related with the ASD neuropathology. Furthermore, it was shown that low levels of these vitamins favor the Th1/Th17 environment in the gut, as well as the growth of enteropathogens linked to GI disorders. DISCUSSION: GI disorders and alterations in the gut microbiota-immune-brain axis seems to be linked with ASD severity. Although unclear, hypovitaminosis appears to regulate peripherally the ASD pathophysiology by modulating the gut microbiota-immune-brain axis, however, more research is still necessary to confirm this hypothesis.