Restoration of cefixime-induced gut microbiota changes by Lactobacillus cocktails and fructooligosaccharides in a mouse model

Studies on the Probiotic, Adhesion, and Induction Properties of Artisanal Lactic Acid Bacteria: to Customize a Gastrointestinal Niche to Trigger Anti-obesity Functions

The primary goals of this work are to explore the potential of probiotic lactic acid bacteria's (LAB) mucin/mucus layer thickening properties and to identify anti-obesity candidate strains that improve appropriate habitat for use with the Akkermansia group population in the future. The HT-29 cell binding, antimicrobial properties, adhesion to the mucin/mucus layer, growth in the presence of mucin, stability during in vitro gastrointestinal (GI) conditions, biofilm formation, and mucin/mucus thickness increment abilities were all assessed for artisanal LAB strains. Sixteen LAB strains out of 40 were chosen for further analysis based on their ability to withstand GI conditions. Thirteen strains remained viable in simulated intestinal fluid, while most showed high viability in gastric juice simulation. Furthermore, 35.9-65.4% of those 16 bacteria adhered to the mucin layer. Besides, different lactate levels were produced, and Streptococcus thermophilus UIN9 exhibited the highest biofilm development. In the HT-29 cell culture, the highest mucin levels were 333.87 µg/mL with O. AK8 at 50 mM lactate, 313.38 µg/mL with Lactobacillus acidophilus NRRL-B 1910 with initial mucin, and 311.41 µg/mL with Lacticaseibacillus casei NRRL-B 441 with initial mucin and 50 mM lactate. Nine LAB strains have been proposed as anti-obesity candidates, with olive isolates of Lactiplantibacillus plantarum being particularly important due to their ability to avoid mucin sugar consumption. Probiotic LAB's attachment to the colonic mucosa and its ability to stimulate HT-29 cells to secrete mucus are critical mechanisms that may support the development of Akkermansia.

Probiotics and Antibiotic-Induced Microbial Aberrations in Children: A Secondary Analysis of a Randomized Clinical Trial

Importance

Probiotics are often considered in children to prevent antibiotic-associated diarrhea. However, the underlying mechanistic effects and impact of probiotics on antibiotic-induced microbiota changes are not well understood.

Objective

To investigate the effects of a multispecies probiotic on the gut microbiota composition in children receiving antibiotics.

Design, Setting, and Participants

This is a secondary analysis of a randomized, quadruple-blind, placebo-controlled clinical trial from February 1, 2018, to May 31, 2021, including 350 children receiving broad-spectrum antibiotics in the inpatient and outpatient settings. Patients were followed up until 1 month after the intervention period. Fecal samples and data were analyzed between September 1, 2022, and February 28, 2023. Eligibility criteria included 3 months to 18 years of age and recruitment within 24 hours following initiation of broad-spectrum systemic antibiotics. In total, 646 eligible patients were approached and 350 participated in the trial.

Intervention

Participants were randomly assigned to receive daily placebo or a multispecies probiotic formulation consisting of 8 strains from 5 different genera during antibiotic treatment and for 7 days afterward.

Main Outcomes and Measures

Fecal stool samples were collected at 4 predefined times: (1) inclusion, (2) last day of antibiotic use, (3) last day of the study intervention, and (4) 1 month after intervention. Microbiota analysis was performed by 16S ribosomal RNA gene sequencing.

Results

A total of 350 children were randomized and collected stool samples from 88 were eligible for the microbiota analysis (54 boys and 34 girls; mean [SD] age, 47.09 [55.64] months). Alpha diversity did not significantly differ between groups at the first 3 times. Shannon diversity (mean [SD], 3.56 [0.75] vs 3.09 [1.00]; P = .02) and inverse Simpson diversity (mean [SD], 3.75 [95% CI, 1.66-5.82] vs -1.31 [95% CI, -3.17 to 0.53]; P = 1 × 10-4) indices were higher in the placebo group compared with the probiotic group 1 month after intervention. Beta diversity was not significantly different at any of the times. Three of 5 supplemented genera had higher relative abundance during probiotic supplementation, but this difference had disappeared after 1 month.

Conclusions and Relevance

The studied probiotic mixture had minor and transient effects on the microbiota composition during and after antibiotic treatment. Further research is needed to understand their working mechanisms in manipulating the microbiome and preventing antibiotic-associated dysbiosis and adverse effects such as antibiotic-associated diarrhea.

Trial Registration

ClinicalTrials.gov Identifier: NCT03334604.

Simultaneous application of oral and intravaginal probiotics for Helicobacter pylori and its antibiotic-therapy-induced vaginal dysbacteriosis

Helicobacter pylori is a prevalent bacterial pathogen globally, implicated in various gastrointestinal disorders. Current recommended antibiotic therapies for H. pylori infection have been proven to be therapeutically insufficient, with low eradication rates and high recurrence rates. Emerging evidence suggests that antibiotic therapy for H. pylori can lead to gastrointestinal and subsequent vaginal dysbiosis, posing challenges for conventional antibiotic approaches. Thus, this article proposes a novel probiotic therapy involving simultaneous oral and intra-vaginal probiotic administration alongside antibiotics for H. pylori treatment, aiming to enhance eradication rates and mitigate dysbiosis. We begin by providing an overview of gastrointestinal and vaginal microbiota and their interconnectedness through the vagina-gut axis. We then review the efficacy of current antibiotic regimens for H. pylori and discuss how antibiotic treatment impacts the vaginal microenvironment. To explore the feasibility of this approach, we evaluate the effectiveness of oral and intra-vaginal probiotics in restoring normal microbiota in the gastrointestinal and vaginal tracts, respectively. Additionally, we analyze the direct mechanisms by which oral and intra-vaginal probiotics act on their respective tracts and discuss potential cross-tract mechanisms. Considering the potential synergistic therapeutic effects of probiotics in both the gastrointestinal and vaginal tracts, dual-channel probiotic therapy holds promise as a more effective approach for H. pylori eradication and dysbiosis mitigation, presenting a novel concept in the collaborative treatment of gastrointestinal and genital disorders.

Prevention and treatment of antibiotics-associated adverse effects through the use of probiotics: A review

BACKGROUND

The human gut hosts a diverse microbial community, essential for maintaining overall health. However, antibiotics, commonly prescribed for infections, can disrupt this delicate balance, leading to antibiotic-associated diarrhea, inflammatory bowel disease, obesity, and even neurological disorders. Recognizing this, probiotics have emerged as a promising strategy to counteract these adverse effects.

AIM OF REVIEW

This review aims to offer a comprehensive overview of the latest evidence concerning the utilization of probiotics in managing antibiotic-associated side effects.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Probiotics play a crucial role in preserving gut homeostasis, regulating intestinal function and metabolism, and modulating the host immune system. These mechanisms serve to effectively alleviate antibiotic-associated adverse effects and enhance overall well-being.

The hidden threat: Environmental toxins and their effects on gut microbiota

The human gut microbiota (GM), which consists of a complex and diverse ecosystem of bacteria, plays a vital role in overall wellness. However, the delicate balance of this intricate system is being compromised by the widespread presence of environmental toxins. The intricate connection between contaminants in the environment and human well-being has garnered significant attention in recent times. Although many environmental pollutants and their toxicity have been identified and studied in laboratory settings and animal models, there is insufficient data concerning their relevance to human physiology. Consequently, research on the toxicity of environmental toxins in GM has gained prominence in recent years. Various factors, such as air pollution, chemicals, heavy metals, and pesticides, have a detrimental impact on the composition and functioning of the GM. This comprehensive review aims to comprehend the toxic effects of numerous environmental pollutants, including antibiotics, endocrine-disrupting chemicals, heavy metals, and pesticides, on GM by examining recent research findings. The current analysis concludes that different types of environmental toxins can lead to GM dysbiosis and have various potential adverse effects on the well-being of animals. We investigate the alterations to the GM composition induced by contaminants and their impact on overall well-being, providing a fresh perspective on research related to pollutant exposure.

Autoinducer-2 promotes the colonization of Lactobacillus rhamnosus GG to improve the intestinal barrier function in a neonatal mouse model of antibiotic-induced intestinal dysbiosis

BACKGROUND

Human health is seriously threatened by antibiotic-induced intestinal disorders. Herein, we aimed to determine the effects of Autoinducer-2 (AI-2) combined with Lactobacillus rhamnosus GG (LGG) on the intestinal barrier function of antibiotic-induced intestinal dysbiosis neonatal mice.

METHODS

An antibiotic-induced intestinal dysbiosis neonatal mouse model was created using antibiotic cocktails, and the model mice were randomized into the control, AI-2, LGG, and LGG + AI-2 groups. Intestinal short-chain fatty acids and AI-2 concentrations were detected by mass spectrometry and chemiluminescence, respectively. The community composition of the gut microbiota was analyzed using 16S rDNA sequencing, and biofilm thickness and bacterial adhesion in the colon were assessed using scanning electron microscopy. Transcriptome RNA sequencing of intestinal tissues was performed, and the mRNA and protein levels of HCAR2 (hydroxycarboxylic acid receptor 2), claudin3, and claudin4 in intestinal tissues were determined using quantitative real-time reverse transcription PCR and western blotting. The levels of inflammatory factors in intestinal tissues were evaluated using enzyme-linked immunosorbent assays (ELISAs). D-ribose, an inhibitor of AI-2, was used to treat Caco-2 cells in vitro.

RESULTS

Compared with the control, AI-2, and LGG groups, the LGG + AI-2 group showed increased levels of intestinal AI-2 and proportions of Firmicutes and Lacticaseibacillus, but a reduced fraction of Proteobacteria. Specifically, the LGG + AI-2 group had considerably more biofilms and LGG on the colon surface than those of other three groups. Meanwhile, the combination of AI-2 and LGG markedly increased the concentration of butyric acid and promoted Hcar2, claudin3 and claudin4 expression levels compared with supplementation with LGG or AI-2 alone. The ELISAs revealed a significantly higher tumor necrosis factor alpha (TNF-α) level in the control group than in the LGG and LGG + AI-2 groups, whereas the interleukin 10 (IL-10) level was significantly higher in the LGG + AI-2 group than in the other three groups. In vitro, D-ribose treatment dramatically suppressed the increased levels of Hcar2, claudin3, and claudin4 in Caco-2 cells induced by AI-2 + LGG.

CONCLUSIONS

AI-2 promotes the colonization of LGG and biofilm formation to improve intestinal barrier function in an antibiotic-induced intestinal dysbiosis neonatal mouse model.

Dietary nobiletin regulated cefuroxime- and levofloxacin-associated "gut microbiota-metabolism" imbalance and intestinal barrier dysfunction in mice

Nobiletin (NOB) exhibits significant biological activities and may be a potential dietary treatment for antibiotic-associated gut dysbiosis. In this study, mice were gavaged with 0.2 mL day-1 of 12.5 g L-1 cefuroxime (LFX) and 10 g L-1 levofloxacin (LVX) for a duration of 10 days, accompanied by 0.05% NOB to investigate the regulatory effect and potential mechanisms of NOB on antibiotic-induced intestinal microbiota disorder and intestinal barrier dysfunction. Our results indicated that dietary NOB improved the pathology of intestinal epithelial cells and the intestinal permeability by upregulating the expression of intestinal tight junction proteins (TJs) and the number of goblet cells. Furthermore, dietary NOB reduced the levels of serum lipopolysaccharide (LPS) and pro-inflammatory factors (TNF-α and IL-1β), thereby facilitating the restoration of the intestinal mucosal barrier. Additionally, dietary NOB increased the abundance of beneficial bacteria f_Lachnospiraceae and regulated the metabolic disorders of short-chain fatty acids (SCFAs) and bile acids (BAs). Notably, NOB supplementation resulted in elevated levels of butyric acid and lithocholic acid (LCA), which contributed to the repair of the intestinal mucosal barrier function and the maintenance of intestinal homeostasis. Collectively, our results propose a healthy dietary strategy for the prevention or mitigation of antibiotic-associated gut dysbiosis by dietary NOB.

Depression-associated gut microbes, metabolites and clinical trials

Depression is one of the most prevalent mental disorders today. Over the past decade, there has been considerable attention given to the field of gut microbiota associated with depression. A substantial body of research indicates a bidirectional communication pathway between gut microbiota and the brain. In this review, we extensively detail the correlation between gut microbiota, including Lactobacillus acidophilus and Bifidobacterium longum, and metabolites such as short-chain fatty acids (SCFAs) and 5-hydroxytryptamine (5-HT) concerning depression. Furthermore, we delve into the potential health benefits of microbiome-targeted therapies, encompassing probiotics, prebiotics, and synbiotics, in alleviating depression. Lastly, we underscore the importance of employing a constraint-based modeling framework in the era of systems medicine to contextualize metabolomic measurements and integrate multi-omics data. This approach can offer valuable insights into the complex metabolic host-microbiota interactions, enabling personalized recommendations for potential biomarkers, novel drugs, and treatments for depression.

Influence of Lactose Supplementation on Regulation of Streptococcus thermophilus on Gut Microbiota

It has been found that Streptococcus thermophilus (S. thermophilus) influenced the gut microbiota and host metabolism with strain specificity in C57BL/6J mice in the previous study, though it remains unclear whether lactose as a dietary factor associated with dairy consumption is involved as the mediator in the interaction. In the present study, integrated analysis of 16S rRNA gene sequencing and untargeted metabolomics by liquid chromatography-mass spectrometry of fecal samples in C57BL/6J mice was applied to evaluate the effect of lactose on the regulation of gut microbiota by two S. thermophilus strains (4M6 and DYNDL13-4). The results showed that the influence of lactose supplementation on gut microbiota induced by S. thermophilus ingestion was strain-specific. Although two S. thermophilus strains ingestion introduced similar perturbations in the fecal microbiota and gut microbial metabolism, the regulation of DYNDL13-4 on the gut microbiota and metabolism was more affected by lactose than 4M6. More specifically, lactose and 4M6 supplementation mainly enriched pathways of d-glutamine and d-glutamate metabolism, alanine, aspartate, and glutamate metabolism, and tryptophan and phenylalanine metabolism in the gut, whereas 4M6 only enriched tryptophan and phenylalanine metabolism. DYNDL13-4-L (DYNDL13-4 with lactose) had significant effects on sulfur, taurine, and hypotaurine metabolism in the gut and on phenylalanine, tyrosine, tryptophan biosynthesis, and linoleic acid metabolism in serum relative to the DYNDL13-4. Our study demonstrated the strain-specific effect of lactose and S. thermophilus supplementation on gut microbiota and host metabolism. However, considering the complexity of the gut microbiota, further research is necessary to provide insights to facilitate the design of personalized fermented milk products as a dietary therapeutic strategy for improving host health.

Responses of the gut microbiota to environmental heavy metal pollution in tree sparrow (Passer montanus) nestlings

Gut microbiota plays a critical role in regulating the health and adaptation of wildlife. However, our understanding of how exposure to environmental heavy metals influences the gut microbiota of wild birds, particularly during the vulnerable and sensitive nestling stage, remains limited. In order to investigate the relationship between heavy metals and the gut microbiota, we analyzed the characteristics of gut microbiota and heavy metals levels in tree sparrow nestlings at different ages (6, 9 and 12-day-old). The study was conducted in two distinct areas: Baiyin (BY), which is heavily contaminated with heavy metals, and Liujiaxia (LJX), a relatively unpolluted area. Our result reveled a decrease in gut microbiota diversity and increased inter-individual variation among nestlings in BY. However, we also observed an increase in the abundance of bacterial groups and an up-regulation of bacterial metabolic functions associated with resistance to heavy metals toxicity in BY. Furthermore, we identified a metal-associated shift in the relative abundance of microbial taxa in 12-day-old tree sparrow nestlings in BY, particularly involving Aeromonadaceae, Ruminococcaceae and Pseudomonadaceae. Moreover, a significant positive correlation was found between the body condition of tree sparrow nestlings and the abundance of Bifidobacteriaceae in BY. Collectively, our findings indicate that the gut microbiota of tree sparrow nestlings is susceptible to heavy metals during early development. However, the results also highlight the presence of adaptive responses that enable them to effectively cope with environmental heavy metal pollution.

Targeting the gut microbiome to control drug pharmacomicrobiomics: the next frontier in oral drug delivery

INTRODUCTION

The trillions of microorganisms that comprise the gut microbiome form dynamic bidirectional interactions with orally administered drugs and host health. These relationships can alter all aspects of drug pharmacokinetics and pharmacodynamics (PK/PD); thus, there is a desire to control these interactions to maximize therapeutic efficacy. Attempts to modulate drug-gut microbiome interactions have spurred advancements within the field of 'pharmacomicrobiomics' and are poised to become the next frontier of oral drug delivery.

AREAS COVERED

This review details the bidirectional interactions that exist between oral drugs and the gut microbiome, with clinically relevant case examples outlining a clear motive for controlling pharmacomicrobiomic interactions. Specific focus is attributed to novel and advanced strategies that have demonstrated success in mediating drug-gut microbiome interactions.

EXPERT OPINION

Co-administration of gut-active supplements (e.g. pro- and pre-biotics), innovative drug delivery vehicles, and strategic polypharmacy serve as the most promising and clinically viable approaches for controlling pharmacomicrobiomic interactions. Targeting the gut microbiome through these strategies presents new opportunities for improving therapeutic efficacy by precisely mediating PK/PD, while mitigating metabolic disturbances caused by drug-induced gut dysbiosis. However, successfully translating preclinical potential into clinical outcomes relies on overcoming key challenges related to interindividual variability in microbiome composition and study design parameters.

Supplementing a specific synbiotic suppressed the incidence of AOM/DSS-induced colorectal cancer in mice

In this study, we evaluated the effect of a specific synbiotic on CAC (AOM/DSS-induced colitis-associated cancer). We confirmed that the synbiotic intervention was able to protect the intestinal barrier and inhibit CAC occurrence via upregulating tight junction proteins and anti-inflammatory cytokines, and downregulating pro-inflammatory cytokines. Moreover, the synbiotic significantly improved the disorder of the colonic microbiota of CAC mice, promoted the formation of SCFAs and the production of secondary bile acids, and alleviated the accumulation of primary bile acids in the CAC mice. Meanwhile, the synbiotic could significantly inhibit the abnormal activation of the intestinal Wnt/β-catenin signaling pathway significantly related to IL-23. In a word, the synbiotic can inhibit the occurrence and development of colorectal tumors and it may be a functional food to prevent inflammation-related colon tumors, and the research also provided a theoretical basis for improving the intestinal microecological environment through diet therapy.

Lactobacillus acidophilus and propionate attenuate Sjögren's syndrome by modulating the STIM1-STING signaling pathway

BACKGROUND

Sjögren's syndrome (SS) is an autoimmune disease characterized by inflammation of the exocrine gland. An imbalance of gut microbiota has been linked to SS. However, the molecular mechanism is unclear. We investigated the effects of Lactobacillus acidophilus (L. acidophilus) and propionate on the development and progression of SS in mouse model.

METHODS

We compared the gut microbiomes of young and old mice. We administered L. acidophilus and propionate up to 24 weeks. The saliva flow rate and the histopathology of the salivary glands were investigated, and the effects of propionate on the STIM1-STING signaling pathway were evaluated in vitro.

RESULTS

Lactobacillaceae and Lactobacillus were decreased in aged mice. SS symptoms were ameliorated by L. acidophilus. The abundance of propionate-producing bacterial was increased by L. acidophilus. Propionate ameliorated the development and progression of SS by inhibiting the STIM1-STING signaling pathway.

CONCLUSIONS

The findings suggest that Lactobacillus acidophilus and propionate have therapeutic potential for SS. Video Abstract.

Dietary 5-demethylnobiletin prevents antibiotic-associated dysbiosis of gut microbiota and damage to the colonic barrier

5-Demethylnobiletin (5DN) is an important ingredient of citrus extract that is rich in polymethoxyflavones (PMFs). In this study, we systemically investigated the preventive effects of 5DN on antibiotic-associated intestinal disturbances. Experimental mice were gavaged 0.2 mL per day of the antibiotic cocktail (12.5 g L^-1 cefuroxime and 10 g L^-1 levofloxacin) for 10 days, accompanied by dietary 0.05% 5DN for 10 and 20 days. The results showed that the combination of cefuroxime and levofloxacin caused swelling of the cecum and injury to the colon tissue. Meanwhile, the balance of intestinal oxidative stress and the barrier function of mice was also damaged by the antibiotics through upregulation of the relative mRNA levels of superoxide dismutase 3 (SOD3), quinine oxidoreductase 1 (NQO1) and glutathione peroxidase 1 (GPX1), and downregulation of the relative protein levels of tight junction proteins (TJs). Moreover, antibiotic exposure led to disorder of the gut microbiota, particularly increased harmful bacteria (Proteobacteria) and decreased beneficial bacteria (Bacteroideta). However, dietary 5DN could reduce antibiotic-associated intestinal damage, evidenced by the results that 5DN alleviated gut oxidative damage and attenuated intestinal barrier injury via increasing the expression of TJs including occludin and zonula occluden1 (ZO1). Additionally, dietary 5DN modulated the composition of the gut microbiota in antibiotic-treated mice by increasing the relative levels of beneficial bacteria, such as Dubosiella and Lactobacillus. Moreover, PMFs increased the contents of isobutyric acid and butyric acid, which were almost eliminated by antibiotic exposure. In conclusion, 5DN could alleviate antibiotic-related imbalance of intestinal oxidative stress, barrier function damage, intestinal flora disorders and the reduction of short-chain fatty acids (SCFAs), which lays a foundation for exploring safer and more effective ways to prevent or mitigate antibiotic-associated intestinal damage.

Polysaccharide from Flammulina velutipes residues protects mice from Pb poisoning by activating Akt/GSK3β/Nrf-2/HO-1 signaling pathway and modulating gut microbiota

Lead (Pb) can cause damages to the brain, liver, kidney, endocrine and other systems. Flammulina velutipes residues polysaccharide (FVRP) has been reported to exhibit anti-heavy metal toxicity on yeast, but its regulating mechanism is unclear. Therefore, the protective effect and the underlying mechanism of FVRP on Pb-intoxicated mice were investigated. The results showed that FVRP could reduce liver and kidney function indexes, serum inflammatory factor levels, and increase antioxidant enzyme activity of Pb-poisoned mice. FVRP also exhibited a protective effect on histopathological damages in organs of Pb-intoxicated mice. Furthermore, FVRP attenuated Pb-induced kidney injury by inhibiting apoptosis via activating the Akt/GSK3β/Nrf-2/HO-1 signaling pathway. In addition, based on 16 s rRNA and ITS-2 sequencing data, FVRP regulated the imbalance of gut microbiota to alleviate the damage of Pb-poisoned mice by increasing the abundance of beneficial microbiota (Lachnospiraceae, Lactobacillaceae, Saccharomyces and Mycosphaerella) and decreasing the abundance of harmful microbiota (Muribaculaceae and Pleosporaceae). In conclusion, FVRP inhibited kidney injury in Pb-poisoned mice by inhibiting apoptosis via activating Akt/GSK3β/Nrf-2/HO-1 signaling pathway, and regulating gut fungi and gut bacteria. This study not only revealed the role of gut fungi in Pb-toxicity, but also laid a theoretical foundation for FVRP as a natural drug against Pb-toxicity.

Current understanding of antibiotic-associated dysbiosis and approaches for its management

Increased exposure to antibiotics during early childhood increases the risk of antibiotic-associated dysbiosis, which is associated with reduced diversity of gut microbial species and abundance of certain taxa, disruption of host immunity, and the emergence of antibiotic-resistant microbes. The disruption of gut microbiota and host immunity in early life is linked to the development of immune-related and metabolic disorders later in life. Antibiotic administration in populations predisposed to gut microbiota dysbiosis, such as newborns, obese children, and children with allergic rhinitis and recurrent infections; changes microbial composition and diversity; exacerbating dysbiosis and resulting in negative health outcomes. Antibiotic-associated diarrhea (AAD), Clostridiodes difficile-associated diarrhea (CDAD), and Helicobacter pylori infection are all short-term consequences of antibiotic treatment that persist from a few weeks to months. Changes in gut microbiota, which persist even 2 years after antibiotic exposure, and the development of obesity, allergies, and asthma are among the long-term consequences. Probiotic bacteria and dietary supplements can potentially prevent or reverse antibiotic-associated gut microbiota dysbiosis. Probiotics have been demonstrated in clinical studies to help prevent AAD and, to a lesser extent, CDAD, as well as to improve H pylori eradication rates. In the Indian setting, probiotics (Saccharomyces boulardii and Bacillus clausii) have been shown to reduce the duration and frequency of acute diarrhea in children. Antibiotics may exaggerate the consequences of gut microbiota dysbiosis in vulnerable populations already affected by the condition. Therefore, prudent use of antibiotics among neonates and young children is critical to prevent the detrimental effects on gut health.

Galactooligosaccharides ameliorate dietary advanced glycation end product-induced intestinal barrier damage in C57BL/6 mice by modulation of the intestinal microbiome

Advanced glycation end products (AGEs) are increasingly recognized as potentially pathogenic components of processed foods, and long-term consumption of dietary AGEs triggers disruption of the intestinal barrier integrity and increases the risk of chronic diseases. Galactooligosaccharides (GOS) as prebiotics can modulate the intestinal microbiota and improve the intestinal barrier integrity. In this study, we aimed to investigate whether GOS could ameliorate the intestinal barrier damage induced by AGEs. The results showed an increased number of goblet cells (AGEs vs. H-GOS, 133.4 vs. 174.7, p < 0.05) and neutral mucin area (PAS positive area, 7.29% vs. 10.05%, p < 0.05). Upregulated expressions of occludin and claudin-1 and improved intestinal barrier integrity were observed in the H-GOS group. Using 16S rRNA sequencing analysis, we found that GOS significantly reduced the high enrichment of Akkermansia (16.95% vs. 1.29%, p < 0.05) induced by dietary AGEs while increasing the content of short-chain fatty acids. Fecal microbiota transplantation (FMT) showed that AGE-induced damage to the intestinal mucus barrier was reversed in the H-GOS transplanted group. Collectively, GOS ameliorated dietary AGE-induced intestinal barrier damage by reversing the dysregulated state of the intestinal microbiota. Our study lays the foundation for further research on dietary guidelines for populations with high AGE diets.

Advances in Lactobacillus Restoration for β-Lactam Antibiotic-Induced Dysbiosis: A System Review in Intestinal Microbiota and Immune Homeostasis

A balanced gut microbiota and their metabolites are necessary for the maintenance of the host's health. The antibiotic-induced dysbiosis can cause the disturbance of the microbial community, influence the immune homeostasis and induce susceptibility to metabolic- or immune-mediated disorders and diseases. The Lactobacillus and their metabolites or components affect the function of the host's immune system and result in microbiota-mediated restoration. Recent data have indicated that, by altering the composition and functions of gut microbiota, antibiotic exposure can also lead to a number of specific pathologies, hence, understanding the potential mechanisms of the interactions between gut microbiota dysbiosis and immunological homeostasis is very important. The Lactobacillus strategies for detecting the associations between the restoration of the relatively imbalanced microbiome and gut diseases are provided in this discussion. In this review, we discuss the recently discovered connections between microbial communities and metabolites in the Lactobacillus treatment of β-lactam antibiotic-induced dysbiosis, and establish the relationship between commensal bacteria and host immunity under this imbalanced homeostasis of the gut microbiota.

Growth differentiation factor 11 delivered by dairy Lactococcus lactis strains modulates inflammation and prevents mucosal damage in a mice model of intestinal mucositis

Mucositis is an inflammation of the gastrointestinal mucosa that debilitate the quality of life of patients undergoing chemotherapy treatments. In this context, antineoplastic drugs, such as 5-fluorouracil, provokes ulcerations in the intestinal mucosa that lead to the secretion of pro-inflammatory cytokines by activating the NF-κB pathway. Alternative approaches to treat the disease using probiotic strains show promising results, and thereafter, treatments that target the site of inflammation could be further explored. Recently, studies reported that the protein GDF11 has an anti-inflammatory role in several diseases, including in vitro and in vivo results in different experimental models. Hence, this study evaluated the anti-inflammatory effect of GDF11 delivered by Lactococcus lactis strains NCDO2118 and MG1363 in a murine model of intestinal mucositis induced by 5-FU. Our results showed that mice treated with the recombinant lactococci strains presented improved histopathological scores of intestinal damage and a reduction of goblet cell degeneration in the mucosa. It was also observed a significant reduction of neutrophil infiltration in the tissue in comparison to positive control group. Moreover, we observed immunomodulation of inflammatory markers Nfkb1, Nlrp3, Tnf, and upregulation of Il10 in mRNA expression levels in groups treated with recombinant strains that help to partially explain the ameliorative effect in the mucosa. Therefore, the results found in this study suggest that the use of recombinant L. lactis (pExu:gdf11) could offer a potential gene therapy for intestinal mucositis induced by 5-FU.

Prospect of bacteria for tumor diagnosis and treatment

In recent decades, the comprehensive cancer treatments including surgery, chemotherapy, and radiotherapy have improved the overall survival rate and quality of life of many cancer patients. However, we are still facing many difficult problems in the cancer treatment, such as unpredictable side effects, high recurrence rate, and poor curative effect. Therefore, the better intervention strategies are needed in this field. In recent years, the role and importance of microbiota in a variety of diseases were focused on as a hot research topic, and the role of some intracellular bacteria of cancer cells in carcinogenesis has recently been discovered. The impact of bacteria on cancer is not limited to their contribution to tumorigenesis, but the overall susceptibility of bacteria to subsequent tumor progression, the development of concurrent infections, and the response to anti-cancer therapy have also been found to be affected. Concerns about the contribution of bacteria in the anti-cancer response have inspired researchers to develop bacteria-based anti-cancer treatments. In this paper, we reviewed the main roles of bacteria in the occurrence and development of tumors, and summarized the mechanism of bacteria in the occurrence, development, and clinical anti-tumor treatment of tumors, providing new insights for the in-depth study of the role of bacteria in tumor diagnosis and treatment. This review aims to provide a new perspective for the development of new technologies based on bacteria to enhance anti-tumor immunotherapy.

Shen-Ling-Bai-Zhu-San Enhances the Antipneumonia Effect of Cefixime in Children by Ameliorating Gut Microflora, Inflammation, and Immune Response

Objective

Shen-Ling-Bai-Zhu-San (SLBZS) is used for treating gastrointestinal disorders. However, the role of SLBZS in treating pneumonia in children is still unclear.

Methods

In this study, children (≥2 and <9 years) with pneumonia were treated with 0.1 g cefixime (cefixime group) or 0.1 g cefixime + 9 g SLBZS (SLBZS + cefixime). The drugs were administered twice daily for 10 days. The therapeutic effects of the two groups were compared. The white blood cell (WBC), neutrophil, and lymphocyte counts; neutrophil-lymphocyte ratio (NLR); serum inflammatory factor levels; and gut microflora were assessed.

Results

The clinical efficacy of SLBZS + cefixime treatment of pneumonia in children was higher than that of cefixime alone (93.3% vs. 86.7%). Both cefixime and SLBZS + cefixime treatments decreased the area of pulmonary inflammatory lesions, reduced white blood cell and neutrophil counts, neutrophil-lymphocyte ratio, inflammation, and increased lymphocyte count in children with pneumonia compared with those before treatment. Moreover, SLBZS enhanced the anti-inflammation and immunity-enhancing effects of cefixime in children with pneumonia. SLBZS + cefixime treatment decreased Enterobacter, Enterococcus, Bacteroides, and Fusobacterium counts and increased Bifidobacterium and Lactobacillus counts. Compared with the cefixime treatment group, the count of the six bacterial strains in the SLBZS + cefixime treatment group was closer to the normal level.

Conclusion

SLBZS enhanced the antipneumonia effect of cefixime in children with pneumonia by ameliorating gut microflora, inflammation, and immune response.

Survival and Interplay of γ-Aminobutyric Acid-Producing Psychobiotic Candidates with the Gut Microbiota in a Continuous Model of the Human Colon

Simple Summary

Appreciable evidence suggests that gut microbiota interact with the brain and play a key role in the pathogenesis of mental illnesses. Psychobiotics are beneficial bacteria (probiotics) or support for such bacteria (prebiotics) that can positively modulate microbiota–gut–brain interactions. Several trials suggest probiotics are involved in normalizing brain processes related to stress responses and mood improvements. Here, we studied the growth and competitiveness of recently identified GABA-producing psychobiotic candidates in a continuous model of the human colon. In summary, supplementation with these probiotic candidates positively modulated the gut microbiome composition and metabolism, suggesting their suitability for gut health-promoting applications.

Abstract

Over decades, probiotic research has focused on their benefits to gut health. Recently, the gut microbiota has been proven to share bidirectional connections with the brain through the gut–brain axis. Therefore, the manipulation of this axis via probiotics has garnered interest. We have recently isolated and characterized in vitro probiotic candidates producing γ-aminobutyric acid (GABA), a major neuromodulator of the enteric nervous system. This study investigates the growth and competitiveness of selected GABA-producing probiotic candidates (Bifidobacterium animalis, Streptococcus thermophilus, and Lactobacillus delbrueckii subsp. bulgaricus) in the presence of human gut microbiota ex vivo in a model mimicking physiological and microbiological conditions of the human proximal colon. Supplementation with GABA-producing probiotic candidates did not affect the overall gut microbiota diversity over 48 h of treatment. However, these candidates modulated the microbiota composition, especially by increasing the Bacteroidetes population, a key gut microbe associated with anti-inflammatory activities. The level of microbiota-generated SCFAs within 12 h of treatment was also increased, compared to the control group. Results from this study demonstrate the probiotic potential of the tested GABA-producing bacteria and their impact on gut microbiota structure and metabolism, suggesting their suitability for gut health-promoting applications.

Lactic acid bacteria alleviate di-(2-ethylhexyl) phthalate-induced liver and testis toxicity via their bio-binding capacity, antioxidant capacity and regulation of the gut microbiota

Di-(2-ethylhexyl) phthalate (DEHP) is a plasticiser that, if absorbed into the human body, can cause various adverse effects including reproductive toxicity, liver toxicity and gut microbiota dysbiosis. So far, some studies have proved that the toxicity of DEHP can be reduced by using antioxidants. However, these candidates all show potential side effects and cannot prevent the accumulation of DEHP in the body, making them unable to be used as a daily dietary supplement to relieve the toxic effects of DEHP. Lactic acid bacteria (LAB) have antioxidant capacity and the ability to adsorb harmful substances. Herein, we investigated the protective effects of five strains of LAB, selected based on our in vitro assessments on antioxidant capacities or bio-binding capacities, against the adverse effects of DEHP exposure in rats. Our results showed that LAB strains with outstanding DEHP/MEHP binding capacities, Lactococcus lactis subsp. lactis CCFM1018 and Lactobacillus plantarum CCFM1019, possess the ability to facilitate the elimination of DEHP and its metabolite mono-(2-ethylhexyl) phthalate (MEHP) with the faeces, decrease DEHP and MEHP level in serum further. Meanwhile, DEHP-induced liver and testicular injuries were effectively alleviated by CCFM1018 and CCFM1019. In addition, CCFM1018 effectively alleviated the DEHP-induced oxidative stress with its strong antioxidant ability. Furthermore, both CCFM1018 and CCFM1019 modulated the gut microbiota, which in turn increased the concentrations of faecal propionate and butyrate and regulated the pathways related to host metabolism. Correlation analysis indicate that DEHP/MEHP bio-binding capacity of LAB plays a crucial role in protecting the body from DEHP exposure, and its antioxidant capacity and the ability to alleviate the gut microbiota dysbiosis are also involved in the alleviation of damage. Thus, LAB with powerful bio-binding capacity of DEHP and MEHP can be considered as a potential therapeutic dietary strategy against DEHP exposure.

Saireito, a Japanese herbal medicine, alleviates leaky gut associated with antibiotic-induced dysbiosis in mice

Antibiotics disrupt normal gut microbiota and cause dysbiosis, leading to a reduction in intestinal epithelial barrier function. Disruption of the intestinal epithelial barrier, which is known as “leaky gut”, results in increased intestinal permeability and contributes to the development or exacerbation of gastrointestinal diseases such as inflammatory bowel disease and irritable bowel syndrome. We have previously reported on a murine model of intestinal epithelial barrier dysfunction associated with dysbiosis induced by the administration of ampicillin and vancomycin. Saireito, a traditional Japanese herbal medicine, is often used to treat autoimmune disorders including ulcerative colitis; the possible mechanism of action and its efficacy, however, remains unclear. In this study, we examined the efficacy of Saireito in our animal model for leaky gut associated with dysbiosis. C57BL/6 mice were fed a Saireito diet for the entirety of the protocol (day1-28). To induce colitis, ampicillin and vancomycin were administered in drinking water for the last seven consecutive days (day22-28). As previously demonstrated, treatment with antibiotics caused fecal occult bleeding, cecum enlargement with black discoloration, colon inflammation with epithelial cell apoptosis, and upregulation of pro-inflammatory cytokines. Oral administration of Saireito significantly improved antibiotics-induced fecal occult bleeding and cecum enlargement by suppressing inflammation in the colon. Furthermore, Saireito treatment ensured the integrity of the intestinal epithelial barrier by suppressing apoptosis and inducing cell adhesion proteins including ZO-1, occludin, and E-cadherin in intestinal epithelial cells, which in turn decreased intestinal epithelial permeability. Moreover, the reduced microbial diversity seen in the gut of mice treated with antibiotics was remarkably improved with the administration of Saireito. In addition, Saireito altered the composition of gut microbiota in these mice. These results suggest that Saireito alleviates leaky gut caused by antibiotic-induced dysbiosis. Our findings provide a potentially new therapeutic strategy for antibiotic-related gastrointestinal disorders.

Bacteria and tumor: Understanding the roles of bacteria in tumor genesis and immunology

In the past, tumor and microbial infection were commonly regarded as independent diseases with few interrelations. The discovery of bacteria in tumor tissue changed the knowledge of bacteria-tumor relationship. Recently, more and more findings have demonstrated the significant effects of bacteria on the genesis, development and metastasis of tumor. Particularly, the influence of bacteria on tumor immunity is of great interest. Bacteria can inhibit the function of immune system through multiple mechanisms. On the other hand, some bacteria can also enhance the immune response and inhibit tumor progression. Understanding the bacteria-tumor interactions is of great importance for developing novel anticancer approaches. Herein, we aim to provide a comprehensive understanding of the tumor/tumor immunology, the biogenesis of bacteria in tumor and the relation of tumorigenesis with bacteria. In addition, the roles of bacteria in tumor immunology and the potential approaches to use bacteria for cancer therapy are discussed.

The role of bacterial translocation in sepsis: a new target for therapy

Sepsis is a leading cause of death in critically ill patients, primarily due to multiple organ failures. It is associated with a systemic inflammatory response that plays a role in the pathogenesis of the disease. Intestinal barrier dysfunction and bacterial translocation (BT) play pivotal roles in the pathogenesis of sepsis and associated organ failure. In this review, we describe recent advances in understanding the mechanisms by which the gut microbiome and BT contribute to the pathogenesis of sepsis. We also discuss several potential treatment modalities that target the microbiome as therapeutic tools for patients with sepsis.

Fructooligosaccharide Reduces Weanling Pig Diarrhea in Conjunction with Improving Intestinal Antioxidase Activity and Tight Junction Protein Expression

This study was to illustrate the effects of fructooligosaccharide (FOS) on the antioxidant capacity, intestinal barrier function, and microbial community of weanling pigs. Results showed that FOS reduced the incidence of diarrhea (6.5 vs. 10.8%) of pigs (p < 0.05) but did not affect growth performance when compared with the control group. A diet supplemented with FOS increased ileal mRNA expression of occludin (1.7 vs. 1.0), claudin-1 (1.9 vs. 1.0), claudin-2 (1.8 vs. 1.0), and claudin-4 (1.7 vs. 1.0), as well as colonic mRNA expression of ZO-1 (1.6 vs. 1.0), claudin-1 (1.7 vs. 1.0), occludin (1.9 vs. 1.0), and pBD-1 (1.5 vs. 1.0) when compared with the control group (p < 0.05). FOS supplementation improved the anti-oxidase activity and expression of nuclear factor erythroid-2 related factor 2 (Nrf2), and decreased concentrations of D-lactate (3.05 U/L vs. 2.83 U/L) and TNF-α (59.1 pg/mL vs. 48.0 pg/mL) in the serum when compared with the control group (p < 0.05). In addition, FOS increased Sharpea, Megasphaera, and Bacillus populations in the gut when compared with the control group (p < 0.05). Association analysis indicated that mRNA expression of occludin and claudin-1 in the ileal mucosa were correlated positively with populations of Sharpea and Bacillus (p < 0.05). Furthermore, mRNA expression of occludin and claudin-1 in the colonic mucosa were correlated positively with abundances of Sharpea, Lactobocillus, and Bifidobacterium (p < 0.05). In conclusion, FOS activated Nrf2 signaling and increased the expression of specific tight junction proteins, which were associated with reduced diarrhea incidence.

Faecal microbiota transplantation alleviates early-life antibiotic-induced gut microbiota dysbiosis and mucosa injuries in a neonatal piglet model

Faecal microbiota transplantation (FMT) is a promising approach to modulate the gut microbiota. Gut microbiota dysbiosis caused by antibiotic administration is a universal problem. This study aimed to evaluate the effect of FMT on the dysbiosis of gut microbiota and metabolic profiles and injury of the intestinal barrier induced by antibiotics and used a neonatal piglet model. Neonatal piglets were administered ampicillin for 3 days, and antibiotic-induced dysbiosis was evaluated by the occurrence of diarrhoea and alteration of gut microbiota. Then, FMT was conducted for 3 days to rebuild the gut microbiota. High-throughput sequencing and a mass spectrometry platform were used for integrated microbiome-metabolome analysis. The results showed that antibiotics led to a decline in the diversity of gut microbiota. Furthermore, there was an increase in the relative abundance of potential pathogenic bacteria, such as Oscillibacter, Pseudomonas and Eubacterium, and an increase in the relative abundance of tetracycline resistance genes (tet genes). FMT restored the diversity and promoted the relative abundance of beneficial bacteria, such as Parabacteroides, Dorea and Parasutterella, while decreasing the relative abundance of tet genes. Untargeted metabolomics analysis found that alpha linolenic acid and linoleic acid metabolism were the key metabolic pathways utilized in the FMT group, and targeted metabolomics analysis further verified the variation in the associated metabolites arachidonic acid and conjugated linoleic acid. FMT also significantly enhanced the relative expression of tight junction (ZO-1, claudin-1 and occludin) and adherens junction (β-catenin, E-cadherin) proteins and anti-inflammatory cytokines (IL-10, TGF-β1) and reduced the production of proinflammatory cytokines (IL-6, IL-1β, TNF-α and IFN-γ) in the colon. FMT not only modulated the gut microbiota composition and microbial metabolism but also reduced the relative abundance of tet genes, improving the intestinal barrier function and inflammatory responses in antibiotic-treated piglets.

Differential effect of polysaccharide and nonpolysaccharide components in Sijunzi decoction on spleen deficiency syndrome and their mechanisms

BACKGROUND

Sijunzi decoction (SJZD), reported in "Tai Ping Hui Min He Ji Ju Fang" of the Song dynasty, is the basic prescription for the treatment of spleen deficiency syndrome (SDS) in traditional Chinese medicine (TCM). It is composed of Ginseng Radix et Rhizoma, Atractylodisa Macricephalae Rhizoma, Poria and Glycyrrhizae Radix et Rhizoma Praeparata Cum Melle.

PURPOSE

This study sought to explore the effects of different components in SJZD (including nonpolysaccharide NPS and active polysaccharide S-3) on SDS rats and their underlying mechanisms.

STUDY DESIGN AND METHODS

First, SDS model rats were established by reserpine injection and then treated with SJZD, NPS and S-3. To clarify their effect on GI motility and immune function, the gastrointestinal (GI) hormone levels in rat serum and their related receptor expressions in rat intestine were detected by enzyme-linked immunosorbent assay (ELISA) and western blot, and the intestinal T lymphocyte expression were quantified by flow cytometry. The levels of SCFAs in feces and serum were measured by gas chromatography-mass spectrometry (GC-MS), and the gut microbiota composition was determined by 16S RNA sequencing. Furthermore, pseudo-germ-free (pGF) and gut microbiota dysbiosis (GMD) model rats were established to verify the key role of the gut microbiota in the treatment of SDS with SJZD, NPS and S-3.

RESULTS

SJZD has a stronger therapeutic effect on intestinal immune and GI hormone secretion in SDS rats, while the efficacy of NPS and S-3 showed slight differences. NPS mainly regulated the secretion of GI hormones in SDS rats and directly improved intestinal immunity by increasing the expression of T lymphocyte cells, while S-3 mainly enhanced intestinal immune function by increasing the expression of T lymphocyte cells and repairing the intestinal barrier in both direct and indirect ways. Additionally, experiments in pGF and GMD rats have proven that the immune-enhancing effects of SJZD, NPS, and S-3 on SDS rats and the regulation of GI hormones of S-3 are related to modulation of the gut microbiota composition, while the regulation of GI hormones by SJZD and NPS is not completely dependent on this modulation. In particular, Lactobacillus, SMB53, Blautia, Dorea, Collinsella and Adlercreutzia were significantly modulated by SJZD, and 3 genera (including Lactobacillus, Dorea and SMB53) were also remarkably regulated by NPS. S-3 significantly increased the abundance of Butyricimonas and Collinsella, which were different from altered genera in the SJZD group.

CONCLUSION

This study uncovered that NPS and S-3 are inseparable effective substances for SJZD in the treatment of SDS rats, in which NPS mainly improves intestinal motility dysfunction and S-3 mainly enhances intestinal immunity. The mediation effect of the gut microbiota is extremely important, but the regulating effect of NPS on gastrointestinal hormones has nothing to do with the gut microbiota.

Protective Effects of Lactobacillus plantarum CCFM8610 against Acute Toxicity Caused by Different Food-Derived Forms of Cadmium in Mice

Cadmium (Cd) is an environmental pollutant that is toxic to almost every human organ. Oral supplementation with lactic acid bacteria (LAB) has been reported to alleviate cadmium toxicity. However, research on the mitigation of cadmium toxicity by LAB is still limited to inorganic cadmium, which is not representative of the varied forms of cadmium ingested daily. In this study, different foodborne forms of cadmium were adopted to establish an in vivo toxicity model, including cadmium–glutathione, cadmium–citrate, and cadmium–metallothionein. The ability of Lactobacillus plantarum CCFM8610 to reduce the toxic effects of these forms of cadmium was further investigated. The 16S rRNA gene sequencing and metabolomics technologies based on liquid chromatography with tandem mass spectrometry (LC–MS/MS) were adopted for the exploration of relevant protective mechanisms. The results demonstrated that the consumption of CCFM8610 can reduce the content of cadmium in mice and relieve the oxidative stress caused by different food–derived forms of cadmium, indicating that CCFM8610 has a promising effect on the remediation of the toxic effects of cadmium food poisoning. Meanwhile, protective effects on gut microflora and serum metabolites might be an important mechanism for probiotics to alleviate cadmium toxicity. This study provides a theoretical basis for the application of L. plantarum CCFM8610 to alleviate human cadmium poisoning.

Glutamine deficiency links clindamycin-induced dysbiosis and intestinal barrier dysfunction in mice

Antibiotics rank as the most powerful weapons against bacterial infection, but their use is often limited by antibiotic-associated diarrhoea (AAD). Here, we reported that glutamine deficiency might act as a new link between clindamycin-induced dysbiosis and intestinal barrier dysfunction during AAD progression. Using a mouse model, we demonstrated that glutamine became a conditionally essential amino acid upon persistent therapeutic-dose clindamycin exposure, evidenced by a dramatic decrease in intestinal glutamine level and glutaminase expression. Mechanistically, clindamycin substantially confounded the abundance of butyrate-producing strains, leading to the deficiency of faecal butyrate which is normally a fundamental fuel for enterocytes, and in turn increased the compensatory use of glutamine. In addition to its pivotal roles in colonic epithelial cell turnover, glutamine was required for nitric oxide production in classic macrophage-driven host defence facilitating pathogen removal. Importantly, oral administration of glutamine effectively attenuated clindamycin-induced dysbiosis and restored intestinal barrier dysfunction in mice. Collectively, the present study highlighted the importance of gut microbiota in host energy homoeostasis and provided a rationale for introducing glutamine supplementation to patients receiving long-term antibiotic treatment.

Nutritional and therapeutic approaches for protecting human gut microbiota from psychotropic treatments

Emerging evidence highlighted the essential role played by the microbiota-gut-brain axis in maintaining human homeostasis, including nutrition, immunity, and metabolism. Much recent work has linked the gut microbiota to many psychiatric and neurodegenerative disorders such as depression, schizophrenia, and Alzheimer's disease. Shared gut microbiota alterations or dysbiotic microbiota have been identified in these separate disorders relative to controls. Much attention has focused on the bidirectional interplay between the gut microbiota and the brain, establishing gut dysbiotic status as a critical factor in psychiatric disorders. Still, the antibiotic-like effect of psychotropic drugs, medications used for the treatment of these disorders, on gut microbiota is largely neglected. In this review, we summarize the current findings on the impact of psychotropics on gut microbiota and how their antimicrobial potency can trigger dysbiosis. We also discuss the potential therapeutic strategies, including probiotics, prebiotics, and fecal transplantation, to attenuate the dysbiosis related to psychotropics intake.

Probiotics, Photobiomodulation, and Disease Management: Controversies and Challenges

In recent decades, researchers around the world have been studying intensively how micro-organisms that are present inside living organisms could affect the main processes of life, namely health and pathological conditions of mind or body. They discovered a relationship between the whole microbial colonization and the initiation and development of different medical disorders. Besides already known probiotics, novel products such as postbiotics and paraprobiotics have been developed in recent years to create new non-viable micro-organisms or bacterial-free extracts, which can provide benefits to the host with additional bioactivity to probiotics, but without the risk of side effects. The best alternatives in the use of probiotics and postbiotics to maintain the health of the intestinal microbiota and to prevent the attachment of pathogens to children and adults are highlighted and discussed as controversies and challenges. Updated knowledge of the molecular and cellular mechanisms involved in the balance between microbiota and immune system for the introspection on the gut-lung-brain axis could reveal the latest benefits and perspectives of applied photobiomics for health. Multiple interconditioning between photobiomodulation (PBM), probiotics, and the human microbiota, their effects on the human body, and their implications for the management of viral infectious diseases is essential. Coupled complex PBM and probiotic interventions can control the microbiome, improve the activity of the immune system, and save the lives of people with immune imbalances. There is an urgent need to seek and develop innovative treatments to successfully interact with the microbiota and the human immune system in the coronavirus crisis. In the near future, photobiomics and metabolomics should be applied innovatively in the SARS-CoV-2 crisis (to study and design new therapies for COVID-19 immediately), to discover how bacteria can help us through adequate energy biostimulation to combat this pandemic, so that we can find the key to the hidden code of communication between RNA viruses, bacteria, and our body.

Is it time to reconsider prophylactic antimicrobial use for hematopoietic stem cell transplantation? a narrative review of antimicrobials in stem cell transplantation

INTRODUCTION

Hematopoietic Stem Cell Transplantation (HSCT) is a life-saving procedure for multiple types of hematological cancer, autoimmune diseases, and genetic-linked metabolic diseases in humans. Recipients of HSCT transplant are at high risk of microbial infections that significantly correlate with the presence of graft-versus-host disease (GVHD) and the degree of immunosuppression. Infection in HSCT patients is a leading cause of life-threatening complications and mortality.

AREAS COVERED

This review covers issues pertinent to infection in the HSCT patient, including bacterial and viral infection; strategies to reduce GVHD; infection patterns; resistance and treatment options; adverse drug reactions to antimicrobials, problems of antimicrobial resistance; perturbation of the microbiome; the role of prebiotics, probiotics, and antimicrobial peptides. We highlight potential strategies to minimize the use of antimicrobials.

EXPERT OPINION

Measures to control infection and its transmission remain significant HSCT management policy and planning issues. Transplant centers need to consider carefully prophylactic use of antimicrobials for neutropenic patients. The judicious use of appropriate antimicrobials remains a crucial part of the treatment protocol. However, antimicrobials' adverse effects cause microbiome diversity and dysbiosis and have been shown to increase morbidity and mortality.

Isomaltooligosaccharide and Bacillus regulate the duration of farrowing and weaning-estrous interval in sows during the perinatal period by changing the gut microbiota of sows

This study investigated the effects of isomaltooligosaccharide (IMO) and Bacillus in perinatal diets on the duration of farrowing and post-weaning estrus, serum reproductive hormone concentrations, and gut microbiota and its metabolites of sows. Multiparous sows (n = 130) were fed diets without IMO (control, CON group), or diets containing only IMO (IMO group), IMO and Bacillus subtilis (IMOS group), IMO and Bacillus licheniformis (IMOL group), and IMO and B. subtilis and B. licheniformis (IMOSL group), respectively. The results indicate that the duration of farrowing and post-weaning estrus was shorter in sows in the IMOS, IMOL, and IMOSL groups, and the weaning-estrous interval was lower in sows in the IMOL greoup. In addition, the lowest fecal score was observed in the IMOL group during d 106 to 112 of gestation. Sows in most of the treatment groups had a higher concentration of serum prolactin and prostaglandin at farrowing, but a lower serum concentration of estradiol, oxytocin, and progesterone on d 18 of lactation than sows in the CON group. The treatment groups had a higher abundance of Candidatus Methanoplasma and Bacillus and a lower abundance of Escherichia-Shigella in their feces at farrowing. Furthermore, the treatment groups had higher concentrations of total short-chain fatty acids (SCFA) in feces at farrowing and a higher concentration of branched fatty acids in feces on d 18 of lactation. Furthermore, the abundance of Bacillus in feces was positively correlated with serum prostaglandin concentrations and fecal total SCFA of sows at farrowing, but was negatively correlated with the duration of farrowing. Overall, dietary IMO and Bacillus supplementation affected the concentration of serum reproductive hormones and the duration of farrowing and post-weaning estrus, and the gut microbiota is a key factor.

Tea polyphenols regulate gut microbiota dysbiosis induced by antibiotic in mice

Tea polyphenols (TPs) are now widely used in foods for various biological activities. However, they are rarely used in foods to regulate gut microbiota dysbiosis induced by antibiotics. We assessed the regulation of TPs on gut microbiota with an antibiotic-induced intestinal flora disorder mouse model. The mice were orally administered with cefixime for 8 days, then received TPs for 28 days. We found that the antibiotic had a profound impact on the gut microbiota. Compared with the normal group, significant decreases in the species richness and diversity and the production of short-chain fatty acids (SCFAs) were still observed 28 days after the antibiotic treatment, although there was no significant difference in the colonic mucosa. TPs significantly alleviated the decrease of the richness and diversity of gut microbiota caused by the antibiotic treatment, and significantly increased the relative abundance of beneficial microbes such as Lactobacillus, Akkermansia, Blautia, Roseburia, and Eubacterium. The function prediction showed that TPs significantly decreased the relative abundance of genes related to human diseases, yet significantly increased the relative abundance of genes related to cell growth and death, cell motility, and energy metabolism. These showed that TPs could regulate the gut microbiota dysbiosis induced by antibiotics, thus decreasing the risk of diseases such as obesity, cancer, and diabetes. These suggest that TPs have a great potential to be used as a functional food ingredient to prevent or reduce adverse effects of antibiotics.

Xianglian Pill ameliorates antibiotic-associated diarrhea by restoring intestinal microbiota and attenuating mucosal damage

ETHNOPHARMACOLOGICAL RELEVANCE

Xianglian Pill (XLP), a traditional Chinese pharmaceutical preparation for the treatment of gastrointestinal disease, possessing anti-inflammatory, anti-microbial and analgesic activities, may represent a promising candidate for the treatment of antibiotic-associated diarrhea (AAD).

AIM OF THE STUDY

This study aimed to unravel the underlying mechanism of XLP on the amelioration of AAD.

MATERIALS AND METHODS

AAD was induced by intragastric administration of a mixture of cefuroxime and levofoxacin (300 mg/kg. bw + 200 mg/kg. bw) for five consecutive days. Then AAD mice were treated with XLP at the dose of 500, 1000 and 2000 mg/kg. bw, respectively for 5 days. The physical manifestations, diarrhea status were monitored during the drug delivery. Histopathology of colon, intestinal microbiota, inflammatory cytokines, tight junction protein and short chain fat acids (SCFAs) were determined.

RESULTS

Mice received cefuroxime and levofoxacin for 5 days developed medium to severe diarrhea. XLP treatment, however, mitigated the diarrhea status. Further evaluation revealed that XLP promoted the recovery of mucosa, maintained the integrity of tight junction, attenuated the inflammatory disorders, restored intestinal microbiota and increased SCFAs level in feces.

CONCLUSION

XLP ameliorates AAD by restoring intestinal microbiota and attenuating mucosal damage.

Antibiotic-induced gut dysbiosis and barrier disruption and the potential protective strategies

The oral antibiotic therapies administered widely to people and animals can cause gut dysbiosis and barrier disruption inevitably. Increasing attention has been directed toward antibiotic-induced gut dysbiosis, which involves a loss of diversity, changes in the abundances of certain taxa and consequent effects on their metabolic capacity, and the spread of antibiotic-resistant bacterial strains. Treatment with beta-lactam, glycopeptide, and macrolide antibiotics is associated with the depletion of beneficial commensal bacteria in the genera Bifidobacterium and Lactobacillus. The gut microbiota is a reservoir for antibiotic resistance genes, the prevalence of which increases sharply after antibiotic ingestion. The intestinal barrier, which comprises secretory, physical, and immunological barriers, is also a target of antibiotics. Antibiotic induced changes in the gut microbiota composition could induce weakening of the gut barrier through changes in mucin, cytokine, and antimicrobial peptide production by intestinal epithelial cells. Reports have indicated that dietary interventions involving prebiotics, probiotics, omega-3 fatty acids, and butyrate supplementation, as well as fecal microbiota transplantation, can alleviate antibiotic-induced gut dysbiosis and barrier injuries. This review summarizes the characteristics of antibiotic-associated gut dysbiosis and barrier disruption, as well as the strategies for alleviating this condition. This information is intended to provide a foundation for the exploration of safer, more efficient, and affordable strategies to prevent or relieve antibiotic-induced gut injuries.

Novel Strategies for Efficient Production and Delivery of Live Biotherapeutics and Biotechnological Uses of Lactococcus lactis: The Lactic Acid Bacterium Model

Lactic acid bacteria (LAB) are traditionally used in fermentation and food preservation processes and are recognized as safe for consumption. Recently, they have attracted attention due to their health-promoting properties; many species are already widely used as probiotics for treatment or prevention of various medical conditions, including inflammatory bowel diseases, infections, and autoimmune disorders. Some LAB, especially Lactococcus lactis, have been engineered as live vehicles for delivery of DNA vaccines and for production of therapeutic biomolecules. Here, we summarize work on engineering of LAB, with emphasis on the model LAB, L. lactis. We review the various expression systems for the production of heterologous proteins in Lactococcus spp. and its use as a live delivery system of DNA vaccines and for expression of biotherapeutics using the eukaryotic cell machinery. We have included examples of molecules produced by these expression platforms and their application in clinical disorders. We also present the CRISPR-Cas approach as a novel methodology for the development and optimization of food-grade expression of useful substances, and detail methods to improve DNA delivery by LAB to the gastrointestinal tract. Finally, we discuss perspectives for the development of medical applications of recombinant LABs involving animal model studies and human clinical trials, and we touch on the main safety issues that need to be taken into account so that bioengineered versions of these generally recognized as safe organisms will be considered acceptable for medical use.

Probiotics, Prebiotics, Synbiotics, and Paraprobiotics as a Therapeutic Alternative for Intestinal Mucositis

Intestinal mucositis, a cytotoxic side effect of the antineoplastic drug 5-fluorouracil (5-FU), is characterized by ulceration, inflammation, diarrhea, and intense abdominal pain, making it an important issue for clinical medicine. Given the seriousness of the problem, therapeutic alternatives have been sought as a means to ameliorate, prevent, and treat this condition. Among the alternatives available to address this side effect of treatment with 5-FU, the most promising has been the use of probiotics, prebiotics, synbiotics, and paraprobiotics. This review addresses the administration of these "biotics" as a therapeutic alternative for intestinal mucositis caused by 5-FU. It describes the effects and benefits related to their use as well as their potential for patient care.

Contributions of Lactobacillus plantarum PC170 administration on the recovery of gut microbiota after short-term ceftriaxone exposure in mice

This study aimed to determine the impact of Lactobacillus plantarum PC170 concurrent with antibiotic treatment and/or during the recovery phase after antibiotic treatment on the body weight, faecal bacterial composition, short-chain fatty acids (SCFAs) concentration, and splenic cytokine mRNA expression of mice. Orally administrated ceftriaxone quantitatively and significantly decreased body weight, faecal total bacteria, Akkermansia muciniphila, and Lactobacillus plantarum, and faecal SCFAs concentration. Ceftriaxone treatment also dramatically altered the faecal microbiota with an increased Chao1 index, decreased species diversities and Bacteroidetes, and more Firmicutes and Proteobacteria. After ceftriaxone intervention, these changes all gradually started to recover. However, faecal microbiota diversities were still totally different from control by significantly increased α- and β-diversities. Bacteroidetes all flourished and became dominant during the recovery process. However, mice treated with PC170 both in parallel with and after ceftriaxone treatment encouraged more Bacteroidetes, Verrucomicrobia, and Actinobacteria, and the diversity by which to make faecal microbiota was very much closer to control. Furthermore, the expression of splenic pro-inflammatory cytokine tumour necrosis factor-α mRNA in mice supplemented with PC170 during the recovery phase was significantly lower than natural recovery. These results indicated that antibiotics, such as ceftriaxone, even with short-term intervention, could dramatically damage the structure of gut microbiota and their abilities to produce SCFAs with loss of body weight. Although such damages could be partly recovered with the cessation of antibiotics, the implication of antibiotics to gut microbiota might remain even after antibiotic treatment. The selected strain PC170 might be a potential probiotic because of its contributions in helping the host animal to remodel or stabilise its gut microbiome and enhancing the anti-inflammatory response as protection from the side effects of antibiotic therapy when it was administered in parallel with and after antibiotic treatment.

Bifidobacterium adolescentis and Lactobacillus rhamnosus alleviate non-alcoholic fatty liver disease induced by a high-fat, high-cholesterol diet through modulation of different gut microbiota-dependent pathways

The incidence of non-alcoholic fatty liver disease (NAFLD) has increased year on year, and the increasing appreciation of the importance of gut microbiota provides novel therapeutic avenues for the treatment of NAFLD. To explore the similarities and differences between lactic acid bacteria (LAB) known to alleviate NAFLD, we selected three strains of Bifidobacterium adolescentis and three strains of Lactobacillus rhamnosus to administer to C57BL/6J mice on a high-fat, high-cholesterol diet (HFHCD) for 23 weeks. Subsequently, the effects of the LAB were evaluated through various measures. The six LAB strains were found to have varying degrees of efficacy in the prevention of NAFLD. We found that there were interspecific and intraspecific differences in the beneficial effects, mainly with respect to energy metabolism, lipid metabolism and short-chain fatty acid concentration. Three strains of B. adolescentis and one strain of L. rhamnosus were found to relieve NAFLD by increasing the concentration of short-chain fatty acids in the intestine of NAFLD mice. The other two strains of L. rhamnosus, LGG and L10-1, relieved NAFLD through different ways, LGG modulated energy metabolism and lipid metabolism, and L10-1 reduced liver inflammation. Examination of gut microbiota indicated that the six LAB strains could block the HFHCD-induced elevation of Firmicutes/Bacteroidetes and alter the dominant species within the gut. These results suggest that B. adolescentis and L. rhamnosus can inhibit the development of NAFLD by regulating gut microbiota, and their use is thus a promising therapeutic strategy.

Shen-ling-bai-zhu-san ameliorates inflammation and lung injury by increasing the gut microbiota in the murine model of Streptococcus pneumonia-induced pneumonia

Background

Shen-ling-bai-zhu-san (SLBZS) regulates inflammation and gut microbiota which are associated with Streptococcus pneumoniae (Spn)-induced pneumonia. So, we studied the therapeutic effect of SLBZS and evaluated whether gut microbiota is associated with the effects of SLBZS in improving Spn-induced pneumonia.

Methods

Spn-induced pneumonia NIH mice were treated by SLBZS and cefixime. A CT scan was performed and Myeloperoxidase (MPO) activity in lung homogenates was determined using the MPO Colorimetric Assay Kit. Inflammation levels in lung homogenates were measured using ELISA. Bacterial load was coated on a TSAII sheep blood agar. Intestinal gut microbiota information was analyzed according to sequencing libraries.

Results

SLBZS decreased bacterial load, reduced wet/dry weight ratio, inhibited myeloperoxidase activity, reduced the neutrophils count, and ameliorated lung injury. Furthermore, SLBZS inhibited interleukin (IL)-1β, IL-6, tumor necrosis factor-α, IL-2, IL-8, IL-12, and interferon-γ secretion and enhanced IL-10 secretion. These results suggest that SLBZS ameliorates lung injury in mice with Spn-induced pneumonia. Moreover, SLBZS reduced inflammatory cytokine levels in a concentration-dependent manner and increased gut microbiota abundance and diversity. After SLBZS treatment, bacteria such as Epsilonbacteraeota, Bacteroidetes, Actinobacteria, Proteobacteria, and Patescibacteria were significantly reduced, while Tenericutes and Firmicutes were significantly increased.

Conclusion

SLBZS ameliorates inflammation, lung injury, and gut microbiota in mice with S. pneumoniae-induced pneumonia.

Traditional Chinese Medicine and Gut Microbiome: Their Respective and Concert Effects on Healthcare

Advances in systems biology, particularly based on the omics approaches, have resulted in a paradigm shift in both traditional Chinese medicine (TCM) and the gut microbiome research. In line with this paradigm shift, the importance of TCM and gut microbiome in healthcare, as well as their interplay, has become clearer. Firstly, we briefly summarize the current status of three topics in this review: microbiome, TCM, and relationship of TCM and microbiome. Second, we focused on TCM's therapeutic effects and gut microbiome's mediation roles, including the relationships among diet, gut microbiome, and health care. Third, we have summarized some databases and tools to help understand the impact of TCM and gut microbiome on diagnosis and treatment at the molecular level. Finally, we introduce the effects of gut microbiome on TCM and host health, with two case studies, one on the metabolic effect of gut microbiome on TCM, and another on cancer treatment. In summary, we have reviewed the current status of the two components of healthcare: TCM and gut microbiome, as well as their concert effects. It is quite clear that as the holobiont, the maintenance of the health status of human would depend heavily on TCM, gut microbiome, and their combined effects.

Molecular mechanisms of probiotic prevention of antibiotic-associated diarrhea

Antibiotic-associated diarrhea (AAD) is a common and unintended adverse effect of antibiotic treatment. It is characterized by the disruption of the gut microbiota, decreased intestinal short chain fatty acid (SCFA) concentrations, accumulation of luminal carbohydrates and colonic bile acids, altered water absorption, and ultimately diarrhea. Probiotics were shown to prevent AAD in numerous clinical trials. This review examines what is currently known about how probiotics reduce the risk for AAD via modulating the gut microbiota, altering nutrient and bile acid metabolism, inducing epithelial solute transporter activity, supporting intestinal barrier function, and influencing the immune system. Although probiotics are frequently prescribed with antibiotic use, mechanistic evidence verifying how they confer protection against AAD is extremely limited. This information is urgently needed for improving recommendations for sustaining probiotic development and for implementing probiotics in clinical settings.

Modulatory effect of Lactobacillus acidophilus KLDS 1.0738 on intestinal short-chain fatty acids metabolism and GPR41/43 expression in β-lactoglobulin-sensitized mice

We investigated the correlation between the beneficial effect of Lactobacillus acidophilus on gut microbiota composition, metabolic activities, and reducing cow's milk protein allergy. Mice sensitized with β-lactoglobulin (β-Lg) were treated with different doses of L. acidophilus KLDS 1.0738 for 4 weeks, starting 1 week before allergen induction. The results showed that intake of L. acidophilus significantly suppressed the hypersensitivity responses, together with increased fecal microbiota diversity and short-chain fatty acids (SCFAs) concentration (including propionate, butyrate, isobutyrate, and isovalerate) when compared with the allergic group. Moreover, treatment with L. acidophilus induced the expression of SCFAs receptors, G-protein-coupled receptors 41 (GPR41) and 43 (GPR43), in the spleen and colon of the allergic mice. Further analysis revealed that the GPR41 and GPR43 messenger RNA expression both positively correlated with the serum concentrations of transforming growth factor-β and IFN-γ (p < .05), but negatively with the serum concentrations of IL-17, IL-4, and IL-6 in the L. acidophilus-treated group compared with the allergic group (p < .05). These results suggested that L. acidophilus protected against the development of allergic inflammation by improving the intestinal flora, as well as upregulating SCFAs and their receptors GPR41/43.

Synergistic and antagonistic interactions between antibiotics and synbiotics in modifying the murine fecal microbiome

Purpose

Pro- and synbiotics have been reported to ameliorate the adverse (dysbiotic) effects of antibiotics on the gut microbial architecture, but little is known how synbiotics and antibiotics interact with each other in shaping the gut microbiota. To explore this mutual interaction we examined, first, the effect of a multi-strain synbiotic on antibiotic-induced dysbiosis and, second, the dysbiotic effect of antibiotics followed by prolonged synbiotic exposure.

Methods

The synbiotic containing nine bacterial strains was administered to male mice via the drinking water, while the antibiotic mix containing bacitracin, meropenem, neomycin, and vancomycin was administered via oral gavage. Two experimental protocols were used. In protocol 1, mice were administered placebo or synbiotic for 3 weeks prior to and during an 11-day vehicle or antibiotic treatment. In protocol 2 the synbiotic was administered for a prolonged period of time, starting 3 weeks prior and continuing for 12 weeks after an 11-day vehicle or antibiotic treatment. Subsequently, the fecal microbiome was analyzed by 16S rRNA sequencing using oligonucleotide primers 16s_515_S3_fwd: GATTGCCAGCAGCCGCGGTAA and 16s_806_S2_rev: GGACTACCAGGGTATCTAAT followed by sequencing using the Ion Torrent One. The final sequence files were analyzed by QIIME 1.8 workflow scripts.

Results

Antibiotic treatment markedly decreased the bacterial richness and diversity of the fecal microbiota. Synbiotic administration for 3 weeks prior to and during an 11-day antibiotic treatment preserved the Lactobacillales and expanded the Verrucomicrobiales and Bifidobacteriales order, but did not prevent the depletion of Bacteroidales and the short-term proliferation of Enterobacteriales. When the synbiotic administration was continued for 12 weeks after the end of antibiotic treatment, the rise of Verrucomicrobiales was maintained, whereas the preservation of Lactobacillales and boost of Bifidobacteriales was lost. The abundance of Clostridiales was enhanced by long-term synbiotic treatment after short-term exposure to antibiotics, while the antibiotic-depleted Bacteroidales underwent a delayed recovery.

Conclusions

There are complex synergistic and antagonistic interactions of synbiotics and antibiotics in influencing distinct bacterial orders of the fecal microbiota. The impact of a short-term antibiotic exposure is profoundly different when analyzed after synbiotic pretreatment or following prolonged synbiotic administration in the post-antibiotic period.

A Review on Gut Remediation of Selected Environmental Contaminants: Possible Roles of Probiotics and Gut Microbiota

Various environmental contaminants including heavy metals, pesticides and antibiotics can contaminate food and water, leading to adverse effects on human health, such as inflammation, oxidative stress and intestinal disorder. Therefore, remediation of the toxicity of foodborne contaminants in human has become a primary concern. Some probiotic bacteria, mainly Lactobacilli, have received a great attention due to their ability to reduce the toxicity of several contaminants. For instance, Lactobacilli can reduce the accumulation and toxicity of selective heavy metals and pesticides in animal tissues by inhibiting intestinal absorption of contaminants and enhancing intestinal barrier function. Probiotics have also shown to decrease the risk of antibiotic-associated diarrhea possibly via competing and producing antagonistic compounds against pathogenic bacteria. Furthermore, probiotics can improve immune function by enhancing the gut microbiota mediated anti-inflammation. Thus, these probiotic bacteria are promising candidates for protecting body against foodborne contaminants-induced toxicity. Study on the mechanism of these beneficial bacterial strains during remediation processes and particularly their interaction with host gut microbiota is an active field of research. This review summarizes the current understanding of the remediation mechanisms of some probiotics and the combined effects of probiotics and gut microbiota on remediation of foodborne contaminants in vivo.