Probiotic use in pediatric kidney transplant recipients: What are current practices, and are they evidence-based? A pediatric nephrology research consortium study

BACKGROUND

Probiotics are living microorganisms that may confer health benefits to their host if administered in sufficient quantities. However, data on the use of probiotics in transplant recipients are scarce.

METHOD

This multi-center survey of pediatric nephrologists aimed to examine variations in practice regarding the use of probiotics in pediatric kidney transplant recipients. The survey was conducted via a 10-item questionnaire (developed in Survey Monkey) administered to pediatric nephrologists participating in the Pediatric Nephrology Research Consortium meeting in April 2023.

RESULTS

Sixty-four pediatric nephrologists completed the survey. Twenty-seven (42.2%) respondents reported having prescribed probiotics to pediatric kidney transplant recipients. The primary reason for probiotic use was the treatment of antibiotic-associated diarrhea (n = 20), with other reasons including recurrent Clostridium difficile infection (n = 15), general gut health promotion (n = 12), recurrent urinary tract infections (n = 8), and parental request (n = 1). Of those who prescribed probiotics, 48.1% held them during periods of neutropenia and 14.8% during central venous line use. Of the 64 respondents, 20 reported the lack of safety data as a concern for using probiotics in kidney transplant recipients.

CONCLUSION

Pediatric nephrologists are increasingly prescribing probiotics to pediatric kidney transplant recipients; nevertheless, substantial practice variations exist. The paucity of safety data is a significant deterrent to probiotic use in this population.

Exploring the Significance of Gut Microbiota in Diabetes Pathogenesis and Management-A Narrative Review

Type 2 diabetes is a disease with significant health consequences for the individual. Currently, new mechanisms and therapeutic approaches that may affect this disease are being sought. One of them is the association of type 2 diabetes with microbiota. Through the enteric nervous system and the gut-microbiota axis, the microbiota affects the functioning of the body. It has been proven to have a real impact on influencing glucose and lipid metabolism and insulin sensitivity. With dysbiosis, there is increased bacterial translocation through the disrupted intestinal barrier and increased inflammation in the body. In diabetes, the microbiota's composition is altered with, for example, a more abundant class of Betaproteobacteria. The consequences of these disorders are linked to mechanisms involving short-chain fatty acids, branched-chain amino acids, and bacterial lipopolysaccharide, among others. Interventions focusing on the gut microbiota are gaining traction as a promising approach to diabetes management. Studies are currently being conducted on the effects of the supply of probiotics and prebiotics, as well as fecal microbiota transplantation, on the course of diabetes. Further research will allow us to fully develop our knowledge on the subject and possibly best treat and prevent type 2 diabetes.

Probiotics an emerging therapeutic approach towards gut-brain-axis oriented chronic health issues induced by microplastics: A comprehensive review

Applications for plastic polymers can be found all around the world, often discarded without any prior care, exacerbating the environmental issue. When large waste materials are released into the environment, they undergo physical, biological, and photo-degradation processes that break them down into smaller polymer fragments known as microplastics (MPs). The time it takes for residual plastic to degrade depends on the type of polymer and environmental factors, with some taking as long as 600 years or more. Due to their small size, microplastics can contaminate food and enter the human body through food chains and webs, causing gastrointestinal (GI) tract pain that can range from local to systemic. Microplastics can also acquire hydrophobic organic pollutants and heavy metals on their surface, due to their large surface area and surface hydrophobicity. The levels of contamination on the microplastic surface are significantly higher than in the natural environment. The gut-brain axis (GB axis), through which organisms interact with their environment, regulate nutritional digestion and absorption, intestinal motility and secretion, complex polysaccharide breakdown, and maintain intestinal integrity, can be altered by microplastics acting alone or in combination with pollutants. Probiotics have shown significant therapeutic potential in managing various illnesses mediated by the gut-brain axis. They connect hormonal and biochemical pathways to promote gut and brain health, making them a promising therapy option for a variety of GB axis-mediated illnesses. Additionally, taking probiotics with or without food can reduce the production of pro-inflammatory cytokines, reactive oxygen species (ROS), neuro-inflammation, neurodegeneration, protein folding, and both motor and non-motor symptoms in individuals with Parkinson's disease. This study provides new insight into microplastic-induced gut dysbiosis, its associated health risks, and the benefits of using both traditional and next-generation probiotics to maintain gut homeostasis.

Bacteria of healthy periodontal tissues as candidates of probiotics: a systematic review

OBJECTIVES

The use of probiotics could promote the balance of the subgingival microbiota to contribute to periodontal health. This study aimed to identify the potential of bacteria commonly associated with healthy periodontal tissues as probiotic candidates.

MATERIAL AND METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, Scopus, Science Direct, ProQuest, and Ovid databases as well as the combination of Medical Subject Headings (MeSH) and non-MeSH terms. Based on the selection criteria, original studies published in English and identifying the microorganisms present in the periodontium of healthy individuals and patients with periodontitis using the high-throughput 16S ribosomal gene sequencing technique were included.

RESULTS

Out of 659 articles, 12 met the criteria for this review. These articles were published from 2012 to 2020 and mainly originated from the United States, China, and Spain. Most of these studies reported adequate criteria for selecting participants, using standardized clinical criteria, and compliance with quality based on the tools used. In periodontal healthy tissue were identified species like Actinomyces viscosus, Actinomyces naeslundii, Haemophilus parainfluenzae, Rothia dentocariosa, Streptococcus sanguinis, Streptococcus mitis, Streptococcus oralis, Streptococcus gordonii, Streptococcus intermedius, and Prevotella nigrescens which have recognized strains with a capacity to inhibit periodontopathogens.

CONCLUSIONS

S. sanguinis, S. oralis, S. mitis, and S. gordonii are among the bacterial species proposed as potential probiotics because some strains can inhibit periodontopathogens and have been reported as safe for humans.

Mutation of the peptide-regulated transcription factor ComR for amidated peptide specificity and heterologous function in Lactiplantibacillus plantarum WCFS1

There is a growing interest in the use of probiotic bacteria as biosensors for the detection of disease. However, there is a lack of bacterial receptors developed for specific disease biomarkers. Here, we have investigated the use of the peptide-regulated transcription factor ComR from Streptococcus spp. for specific peptide biomarker detection. ComR exhibits a number of attractive features that are potentially exploitable to create a biomolecular switch for engineered biosensor circuitry within the probiotic organism Lactiplantibacillus plantarum WCFS1. Through iterative design-build-test cycles, we developed a genomically integrated, ComR-based biosensor circuit that allowed WCFS1 to detect low nanomolar concentrations of ComR's cognate peptide XIP. By screening a library of ComR proteins with mutant residues substituted at the K100 position, we identified mutations that increased the specificity of ComR toward an amidated version of its cognate peptide, demonstrating the potential for ComR to detect this important class of biomarker.IMPORTANCEUsing bacteria to detect disease is an exciting possibility under active study. Detecting extracellular peptides with specific amino acid sequences would be particularly useful as these are important markers of health and disease (biomarkers). In this work, we show that a probiotic bacteria (Lactiplantibacillus plantarum) can be genetically engineered to detect specific extracellular peptides using the protein ComR from Streptococcus bacteria. In its natural form, ComR allowed the probiotic bacteria to detect a specific peptide, XIP. We then modified XIP to be more like the peptide biomarkers found in humans and engineered ComR so that it activated with this modified XIP and not the original XIP. This newly engineered ComR also worked in the probiotic bacteria, as expected. This suggests that with additional engineering, ComR might be able to activate with human peptide biomarkers and be used by genetically engineered probiotic bacteria to better detect disease.

Supplementation of Heat-Treated Lactiplantibacillus plantarum nF1 Changes the Production of Short-Chain Fatty Acids in Healthy Infants

Background

Imbalance of the gut microbiome and decrease in the number of short-chain fatty acid (SCFA)-producing bacteria often affect human health by altering intestinal and immune homeostasis. The use of probiotics has been shown to be an attractive method to modulate gut microbiota to prevent or treat intestinal dysbiosis. Likewise, this study aimed to determine whether the oral consumption of heat-treated Lactiplantibacillus plantarum nF1 (HLp-nF1) induces changes in the gut environment in healthy infants by measuring changes in fecal SCFAs.

Methods

The study enrolled 43 infants aged under 2 months, with 30 infants in the HLp-nF1 group receiving HLp-nF1 orally (2.5 × 1010 cells/g/pack, daily dose of two packs) for 8 weeks. The fecal samples were collected and the questionnaires were administered at weeks 0 and 8.

Results

The concentrations of the total SCFAs, acetate, propionate, and butyrate significantly increased following HLp-nF1 supplementation (P < 0.0001, P < 0.0001, P < 0.0001, and P=0.028, respectively).

Conclusions

Supplementation of HLp-nF1 has a positive effect on SCFA production and could be a potentially useful and straightforward method to manipulate SCFA formation.

The Role of Probiotics in the Prevention of Clostridioides difficile Infection in Patients with Chronic Kidney Disease

In patients suffering from chronic kidney disease (CKD), substantial unfavourable alterations in the intestinal microbiota composition, i.e., dysbiosis, have been noted. The main causes of such dysbiosis among others are insufficient dietary fibre content in the diet, fluid restrictions, medications used, and physical activity limitation. One clinically important consequence of dysbiosis in CKD patients is high risk of Clostridioides difficile infection (CDI). In observational studies, it was found that CDI is more frequent in CKD patients than in the general population. This appears to be related to high hospitalization rate and more often antibiotic therapy use, leading up to the occurrence of dysbiosis. Therefore, the use of probiotics in CKD patients may avert changes in the intestinal microbiota, which is the major risk factor of CDI. The aim of this review paper is to summarize the actual knowledge concerning the use of probiotics in CDI prevention in CKD patients in the context of CDI prevention in the general population.

Stable expression of HIV-1 MPER extended epitope on the surface of the recombinant probiotic bacteria Escherichia Coli Nissle 1917 using CRISPR/Cas9

BACKGROUND

Mucosal vaccines have the potential to induce protective immune responses at the sites of infection. Applying CRISPR/Cas9 editing, we aimed to develop a probiotic-based vaccine candidate expressing the HIV-1 envelope membrane-proximal external region (MPER) on the surface of E. coli Nissle 1917.

RESULTS

The HIV-1 MPER epitope was successfully introduced in the porin OmpF of the E. coli Nissle 1917 (EcN-MPER) and the modification was stable over 30 passages of the recombinant bacteria on the DNA and protein level. Furthermore, the introduced epitope was recognized by a human anti-HIV-1 gp41 (2F5) antibody using both live and heat-killed EcN-MPER, and this antigenicity was also retained over 30 passages. Whole-cell dot blot suggested a stronger binding of anti-HIV-1 gp41 (2F5) to heat-killed EcN-MPER than their live counterpart. An outer membrane vesicle (OMV) - rich extract from EcN-MPER culture supernatant was equally antigenic to anti-HIV-1 gp41 antibody which suggests that the MPER antigen could be harboured in EcN-MPER OMVs. Using quantitative ELISA, we determined the amount of MPER produced by the modified EcN to be 14.3 µg/108 cfu.

CONCLUSIONS

The CRISPR/Cas9 technology was an effective method for establishment of recombinant EcN-MPER bacteria that was stable over many passages. The developed EcN-MPER clone was devoid of extraneous plasmids and antibiotic resistance genes which eliminates the risk of plasmid transfer to animal hosts, should this clone be used as a vaccine. Also, the EcN-MPER clone was recognised by anti-HIV-1 gp41 (2F5) both as live and heat-killed bacteria making it suitable for pre-clinical evaluation. Expression of OmpF on bacterial surfaces and released OMVs identifies it as a compelling candidate for recombinant epitope modification, enabling surface epitope presentation on both bacteria and OMVs. By applying the methods described in this study, we present a potential platform for cost-effective and rational vaccine antigen expression and administration, offering promising prospects for further research in the field of vaccine development.

Characterization of Lactococcus lactis 11/19-B1 Isolated from Kiwi Fruit as a Potential Probiotic and Paraprobiotic

Probiotics are live bacteria used as food additives that are beneficial to human health. Lactococcus lactis 11/19-B1 strain isolated from kiwi fruit stimulates innate immunity in silkworms. Intake of yogurt containing the living 11/19-B1 strain significantly decreases the level of low-density lipoproteins (LDLs) in high-LDL volunteers and improves atopic dermatitis in humans. In this study, the probiotic properties of the 11/19-B1 strain, such as sensitivity to antimicrobial compounds, biogenic amine production, some virulence genes for human health, antimicrobial activity, tolerance to gastric acid and bile acids, and ability to adhere to the intestinal mucosa, were evaluated. The 11/19-B1 strain did not show resistance to the tested antimicrobial compounds except cefoxitin and fosfomycin. In addition, no production of amines that can harm humans, the antimicrobial activity required for probiotics, and the absence of adhesion to Caco-2 cells suggest that it is unlikely to attach to the intestinal epithelium. The 11/19-B1 strain grew in 0.3% but not in 1% bile salt. In the presence of 2% skim milk, the survival rate of the 11/19-B1 strain under simulated gastrointestinal tract conditions was 67% even after 4 h. These results indicate that the 11/19-B1 strain may function as a probiotic or paraprobiotic to be utilized in the food industry.

Probiotic Lactobacillus and the potential risk of spreading antibiotic resistance: a systematic review

Background and purpose

Lactobacillus, the most popular probiotic, has recently gained more attention because it is a potential reservoir of antibiotic resistance. This review summarized and discussed the phenotypic-genotypic characteristics of antibiotic resistance.

Experimental approach

Google Scholar, PubMed, Web of Science, and Scopus were searched up to February 2022. The inclusion criteria were all studies testing antibiotic resistance of probiotic Lactobacillus strains present in human food supplementation and all human/animal model studies in which transferring antibiotic-resistant genes from Lactobacillus strains to another bacterium were investigated.

Findings/Results

Phenotypic and genotypic characterization of Lactobacillus probiotics showed that the most antibiotic resistance was against protein synthesis inhibitors (fourteen studies, 87.5%) and cell wall synthesis inhibitors (ten studies, 62.5%). Nine of these studies reported the transfer of antibiotic resistance from Lactobacillus probiotic as donor species to pathogenic bacteria and mostly used in vitro methods for resistance gene transfer.

Conclusion and implications

The transferability of resistance genes such as tet and erm in Lactobacillus increases the risk of spreading antibiotic resistance. Further studies need to be conducted to evaluate the potential spread of antibiotic resistance traits via probiotics, especially in elderly people and newborns.

Roles of Gut Microbiota in Alcoholic Liver Disease

Alcoholic liver disease (ALD)-one of the most common liver diseases - involves a wide range of disorders, including asymptomatic hepatic steatosis, alcoholic hepatitis (AH), liver fibrosis, and cirrhosis. Alcohol consumption induces a weakened gut barrier and changes in the composition of the gut microbiota. The presence of CYP2E1 and its elevated levels in the gastrointestinal tract after alcohol exposure lead to elevated levels of ROS and acetaldehyde, inducing inflammation and oxidative damage in the gut. At the same time, the influx of harmful molecules such as the bacterial endotoxin LPS and peptidogly from gut dysbiosis can induce intestinal inflammation and oxidative damage, further compromising the intestinal mucosal barrier. In this process, various oxidative stress-mediated post-translational modifications (PTMs) play an important role in the integrity of the barrier, eg, the presence of acetaldehyde will result in the sustained phosphorylation of several paracellular proteins (occludin and zona occludens-1), which can lead to intestinal leakage. Eventually, persistent oxidative stress, LPS infiltration and hepatocyte damage through the enterohepatic circulation will lead to hepatic stellate cell activation and hepatic fibrosis. In addition, probiotics, prebiotics, synbiotics, fecal microbial transplantation (FMT), bioengineered bacteria, gut-restricted FXR agonists and others are promising therapeutic approaches that can alter gut microbiota composition to improve ALD. In the future, there will be new challenges to study the interactions between the genetics of individuals with ALD and their gut microbiome, to provide personalized interventions targeting the gut-liver axis, and to develop better techniques to measure microbial communities and metabolites in the body.

Evaluation of Enterococcal Probiotic Usage and Review of Potential Health Benefits, Safety, and Risk of Antibiotic-Resistant Strain Emergence

Enterococci are often used in probiotics but can also cause nosocomial infections. As such, enterococcal consumption may have beneficial health effects, but a thorough evaluation of virulence absence and risk of antibiotic resistance spread is needed at the strain level. This article reviewed ten online health product shopping websites in the US. On these websites, 23 probiotic products using enterococci were found across 12 companies. In addition, this article reviewed studies that demonstrated the probiotic potential of enterococcal consumption (e.g., gastrointestinal and respiratory disease, hyperlipidemia alleviation, as well as infection prevention). To investigate the safety aspects of enterococci, the present work examined studies evaluating virulence factors and antibiotic resistance. Furthermore, this article assessed research that explored these virulent factors, specifically in probiotics containing enterococci, as well as the potential transfer mechanism of their antibiotic resistance. Based on reviewed data, enterococcal probiotic consumption has been proven beneficial for conditions or symptoms of multiple diseases without any apparent adverse effects. However, due to the plasmid- or transposon-mediated gene transfer ability of enterococci, surveillance monitoring and further studies regarding enterococcal consumption are warranted. Future studies that identify enterococcal strains safe to use in probiotics without virulence factors and antibiotic resistance are imperative for evidence-based decisions by health organizations and government agencies.

A Three-Arm, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Safety of Lactobacillus salivarius AP-32 and Bifidobacterium animalis CP-9 Used Individually in Healthy Infants

Probiotics are considered safe and beneficial to human health. However, the safety of Lactobacillus salivarius AP-32 and Bifidobacterium animalis CP-9 in infants has not been confirmed. This study was to assess the safety of long-term oral administration of L. salivarius AP-32 and B. animalis CP-9 in healthy infants compared with placebo. A three-arm, randomized, double-blind, placebo-controlled trial was conducted in healthy, full-term infants. Eighty-eight infants between 7 days and 2 months (60 ± 7 days) of age were selected and randomized to treatment with L. salivarius AP-32, B. animalis CP-9 or placebo for 4 months. The unblinding indicated subjects were randomized to receive B. animalis CP-9 (N = 28), L. salivarius AP-32 (N = 29), or placebo (N = 31). A total of 76 infants completed the 4-month treatment with fully compliance. The primary outcome was weight gain, with no significant difference in infant weight at 4 months when comparing AP-32 or CP-9 group with the placebo group, either. The head circumference and recumbent length of the CP-9 group were not significantly different from those of the placebo group. The recumbent length of the AP-32 group was slightly lower than that in the placebo group at month 4, but there was no difference between the two groups in head circumference. Overall, the growth trend of all treatments was similar without significant difference. Furthermore, there were no apparent differences between each group in digestive tolerance, the occurrence of adverse events, crying/fussing time and episodes, alpha diversity, and beta diversity. The CP-9 group showed a significant increase in the abundance of the Bacteroides genus, while the AP-32 group demonstrated a significant increase in the abundance of the Lactobacillus genus when comparing the two probiotic groups. Our study findings indicate that the oral administration of both AP-32 and CP-9 strains has a positive impact on the maintenance of a healthy gut flora in infants. Long-term use of L. salivarius AP-32 or B. animalis CP-9 is safe for infants from 7 days to 6 months of age.

The Potential Value of Probiotics after Dental Implant Placement

Dental implantation is currently the optimal solution for tooth loss. However, the health and stability of dental implants have emerged as global public health concerns. Dental implant placement, healing of the surgical site, osseointegration, stability of bone tissues, and prevention of peri-implant diseases are challenges faced in achieving the long-term health and stability of implants. These have been ongoing concerns in the field of oral implantation. Probiotics, as beneficial microorganisms, play a significant role in the body by inhibiting pathogens, promoting bone tissue homeostasis, and facilitating tissue regeneration, modulating immune-inflammatory levels. This review explores the potential of probiotics in addressing post-implantation challenges. We summarize the existing research regarding the importance of probiotics in managing dental implant health and advocate for further research into their potential applications.

Photodynamic Therapy, Probiotics, Acetic Acid, and Essential Oil in the Treatment of Chronic Wounds Infected with Pseudomonas aeruginosa

As a prevalent medical problem that burdens millions of patients across the world, chronic wounds pose a challenge to the healthcare system. These wounds, often existing as a comorbidity, are vulnerable to infections. Consequently, infections hinder the healing process and complicate clinical management and treatment. While antibiotic drugs remain a popular treatment for infected chronic wounds, the recent rise of antibiotic-resistant strains has hastened the need for alternative treatments. Future impacts of chronic wounds are likely to increase with aging populations and growing obesity rates. With the need for more effective novel treatments, promising research into various wound therapies has seen an increased demand. This review summarizes photodynamic therapy, probiotics, acetic acid, and essential oil studies as developing antibiotic-free treatments for chronic wounds infected with Pseudomonas aeruginosa. Clinicians may find this review informative by gaining a better understanding of the state of current research into various antibiotic-free treatments. Furthermore. this review provides clinical significance, as clinicians may seek to implement photodynamic therapy, probiotics, acetic acid, or essential oils into their own practice.

Beneficial Effects of Probiotics on Benign Gynaecological Disorders: A Review

Probiotics are live microorganisms that confer beneficial effects on human health when an adequate dose is administered. Recently, the use of probiotics has gained tremendous interest from the public due to its promising effects in the management of various reproductive diseases. However, the review of probiotics' benefits on benign gynaecological disorders, including vaginal infections, polycystic ovary syndrome (PCOS) and endometriosis, remains scarce. Therefore, this review is built on current knowledge on the beneficial effects of probiotics against selected benign gynaecological disorders. Recent findings point out that probiotics' supplementation in different clinical and in vivo models showed promising health effects and results in the amelioration of disease symptoms. Thus, in this review, we showed the findings of both studies performed in clinical settings and animal studies. However, current information, solely based on clinical trials or animal studies, is inadequate in communicating the excellent findings on the beneficial effects of probiotics on human health. Therefore, future clinical intervention studies are required to further elucidate the evidence of the benefits of probiotics benefits regarding these gynaecological disorders.

A case of Lactobacillus jensenii associated native valve endocarditis

Lactobacillus jensenii is rarely reported as a cause of endocarditis in immunocompetent patients. We describe a case of Lactobacillus jensenii associated native valve endocarditis that was identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) technology. While most Lactobacillus species are generally resistant to vancomycin, Lactobacillus jensenii is frequently susceptible, but treatment requires accurate susceptibility results followed by timely medical and surgical intervention. Probiotic use in patients can be a risk factor for infection with Lactobacillus species.

The isolation, identification, whole-genome sequencing of Clostridium butyricum LV1 and its effects on growth performance, immune response, and disease-resistance of Litopenaeus vannamei

In this study, a strain of Clostridium butyricum was isolated from the intestine of Litopenaeus vannamei with the method of anaerobic microbial isolation and culture. Next, the probiotic properties of LV1 were evaluated with susceptibility tests, tolerance tests, and whole genome sequencing in vivo and in vitro, followed by the analysis of the effect of LV1 on the growth performance, immune response, and disease resistance of Litopenaeus vannamei. According to the results, the 16 S rDNA sequence of LV1 was 100% homolofgous to the reference sequence of Clostridium butyricum. Moreover, LV1 was resistant to several antibiotics including amikacin, streptomycin, and gentamicin and highly tolerated artificial gastric and artificial intestinal fluids. The whole genome of LV1 was 4625,068 bp in size and included 4336 coding genes. Among these genes, GO, KEGG, and COG databases exhibited the highest number of genes annotated to metabolic pathway classes and 105 genes annotated as glycoside hydrolases. Meanwhile, 176 virulence genes were predicted. The use of diets supplemented with 1.2 × 10⁹ CFU/kg of LV1 live cells significantly increased the weight gain and specific growth rates of Litopenaeus vannamei and the activity of serum superoxide dismutase, glutathione peroxidase, acid phosphatase, and alkaline phosphatase (P < 0.05). Meanwhile, the use of these diets markedly improved the relative expression of intestinal immunity- and growth-related genes. In conclusion, LV1 has excellent probiotic properties. Specifically, the addition of 1.2 × 10⁹ CFU/kg of LV1 live cells to the diet improved the growth performance, immune response, and disease-resistance of Litopenaeus vannamei.

Dysbiome and Its Role in Surgically Relevant Medical Disease

Several surgically relevant conditions are directly or indirectly influenced by the human microbiome. Different microbiomes may be found within, or along, specific organs and intra-organ variation is common. Such variations include those found along the course of the gastrointestinal tract as well as those on different regions of the skin. A variety of physiologic stressors and care interventions may derange the native microbiome. A deranged microbiome is termed a dysbiome and is characterized by decreased diversity and an increase in the proportion of potentially pathogenic organisms; the elaboration of virulence factors coupled with clinical consequences defines a pathobiome. Specific conditions such as Clostridium difficile colitis, inflammatory bowel disease, obesity, and diabetes mellitus are tightly linked to a dysbiome or pathobiome. Additionally, massive transfusion after injury appears to derange the gastrointestinal microbiome as well. This review explores what is known about these surgically relevant clinical conditions to chart how non-surgical interventions may support surgical undertakings or potentially reduce the need for operation.

Lactobacillus Bacteremia and Probiotics: A Review

Lactobacilli are widely found in nature, are commensal microbes in humans, and are commonly used as probiotics. Concerns about probiotic safety have arisen due to reports of bacteremia and other Lactobacillus-associated infections. We reviewed the literature for articles on the pathogenicity of Lactobacillus spp. bacteremia and reports of probiotics in these patients. Our aim is to review these articles and update the present knowledge on the epidemiology of Lactobacillus spp. bacteremia and determine the role of probiotics in Lactobacillus bacteremia. Lactobacillus bacteremia is infrequent but has a higher risk of mortality and risk factors, including severe underlying diseases, immune system suppression, admission to intensive care units, and use of central venous catheters. A variety of Lactobacillus species may cause bacteremia and may or may not be associated with probiotic exposure. To determine if oral probiotics are the source of these infections, the blood isolates and the oral probiotic strain(s) must be compared by sensitive identification methods. The prevalence of Lactobacillus bacteremia is infrequent but is more common in patients taking probiotics compared to those not taking probiotics. Three probiotics (Lacticaseibacillus rhamnosus GG, Lactiplantibacillus plantarum, and Lacticaseibacillus paracasei) were directly linked with blood isolates from bacteremia patients using molecular identification assays.

Potential Probiotic Lactic Acid Bacteria with Anti-Penicillium expansum Activity from Different Species of Tunisian Edible Snails

This study aimed to isolate lactic acid bacteria (LAB) from the digestive tract, meat and slime of edible snails (Helix lucorum, Helix aspersa and Eobania vermiculata) and investigate their antagonistic activity against Penicillium expansum. They were then characterized for their probiotic potential. Among 900 bacterial isolates, 47 LAB exhibiting anti-P. expansum activity were identified through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as Levilactobacillus brevis (25), Lactococcus lactis (3), Enterococcus faecium (12), Enterococcus faecalis (4), Enterococcus casseliflavus (1), and Enterococcus mundtii (2). Sixty-two percent of the strains were tolerant to 100 mg/L of lysozyme. Seventy two percent of the isolates were able to survive at pH 3 and most of them tolerate 2.5% bile salt concentration. Moreover, 23% of the strains displayed bile salt hydrolase activity. Interestingly, all strains were biofilm strong producers. However, their auto- and co-aggregation properties were time and pH dependent with high aggregative potentiality at pH 4.5 after 24 h. Remarkably, 48.94% of the strains showed high affinity to chloroform. The safety assessment revealed that the 47 LAB had no hemolytic activity and 64% of them lacked mucin degradation activity. All isolated strains were susceptible to gentamycin, streptomycin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole. Overall, 43 LAB strains showed inhibitory activity against a broad spectrum of pathogenic Gram-positive and gram-negative bacteria, fungi, and yeast. Our findings suggest that L. brevis (EVM12 and EVM14) and Ent. faecium HAS34 strains could be potential candidates for probiotics with interesting antibacterial and anti-P. expansum activities.

Commercial probiotic products in public health: current status and potential limitations

Consumption of commercial probiotics for health improvement and disease treatment has increased in popularity among the public in recent years. The local shops and pharmacies are brimming with various probiotic products such as probiotic food, dietary supplement and pharmaceuticals that herald a range of health benefits, from nutraceutical benefits to pharmaceutical effects. However, although the probiotic market is expanding rapidly, there is increasing evidence challenging it. Emerging insights from microbiome research and public health demonstrate several potential limitations of the natural properties, regulatory frameworks, and market consequences of commercial probiotics. In this review, we highlight the potential safety and performance issues of the natural properties of commercial probiotics, from the genetic level to trait characteristics and probiotic properties and further to the probiotic-host interaction. Besides, the diverse regulatory frameworks and confusing probiotic guidelines worldwide have led to product consequences such as pathogenic contamination, overstated claims, inaccurate labeling and counterfeit trademarks for probiotic products. Here, we propose a plethora of available methods and strategies related to strain selection and modification, safety and efficacy assessment, and some recommendations for regulatory agencies to address these limitations to guarantee sustainability and progress in the probiotic industry and improve long-term public health and development.

A, Bhardwaj S, Yadav NK, Patel A, Patel A. Gut Microbiota Interventions for the Management of Obesity: A Literature Review

The gut microbiota (GM) has been recognized as an important factor in the development of metabolic diseases such as obesity; it has been reported that the composition of the GM differs in obese and lean subjects, suggesting that microbiota dysbiosis can contribute to changes in body weight. Dysbiosis occurs due to an imbalance in the composition of gut bacteria, changes in the metabolic process, or changes in the distribution of microbiota within the gut. Dysbiosis can change the functioning of the intestinal barrier and the gut-associated lymphoid tissues (GALT). Microbial manipulation may help with preventing or treating weight gain and associated comorbidities. Approaches to this may range from dietary manipulation, which is suitable to treat the individual’s microflora, to probiotics, prebiotics, synbiotics, and fecal microbiota transplant (FMT).

Potential Application of Living Microorganisms in the Detoxification of Heavy Metals

Heavy metal (HM) exposure remains a global occupational and environmental problem that creates a hazard to general health. Even low-level exposure to toxic metals contributes to the pathogenesis of various metabolic and immunological diseases, whereas, in this process, the gut microbiota serves as a major target and mediator of HM bioavailability and toxicity. Specifically, a picture is emerging from recent investigations identifying specific probiotic species to counteract the noxious effect of HM within the intestinal tract via a series of HM-resistant mechanisms. More encouragingly, aided by genetic engineering techniques, novel HM-bioremediation strategies using recombinant microorganisms have been fruitful and may provide access to promising biological medicines for HM poisoning. In this review, we summarized the pivotal mutualistic relationship between HM exposure and the gut microbiota, the probiotic-based protective strategies against HM-induced gut dysbiosis, with reference to recent advancements in developing engineered microorganisms for medically alleviating HM toxicity.

Influence of Probiotics in Prevention and Treatment of Patients Who Undergo Chemotherapy or/and Radiotherapy and Suffer from Mucositis, Diarrhoea, Constipation, Nausea and Vomiting

The administration of probiotics to patients treated with chemo- and/or radiotherapy is assumed to be beneficial. The aim of this study was to evaluate the effects of probiotic intake on the severity of selected gastrointestinal side effects of chemotherapy and radiotherapy. The searched databases included PubMed, Web of Science, and Scopus from which twenty-one studies were included. Most of them concerned diarrhoea, however, two of the studies examined constipation, another two nausea and vomiting, and eight of the included studies regarded mucositis. The total number of patients equalled 2621. The time of the conducted therapy, the administered species, neoplasm pathology, and adjuvant therapy varied. The outcome was assessed by gathering information about the statistical significance of the improvements. An enhancement was observed in thirteen studies, where probiotics had a significant impact on each of the included chemo- and/or radiotherapy side effects. However, the heterogeneity of the assessed data makes it impossible to state a firm conclusion.

Whole genome sequencing for the risk assessment of probiotic lactic acid bacteria

Probiotic bacteria exhibit beneficial effects on human and/or animal health, and have been widely used in foods and fermented products for decades. Most probiotics consist of lactic acid bacteria (LAB), which are used in the production of various food products but have also been shown to have the ability to prevent certain diseases. With the expansion of applications for probiotic LAB, there is an increasing concern with regard to safety, as cases with adverse effects, i.e., severe infections, transfer of antimicrobial resistance genes, etc., can occur. Currently, in vitro assays remain the primary way to assess the properties of LAB. However, such methodologies are not meeting the needs of strain risk assessment on a high-throughput scale, in the context of the evolving concept of food safety. Analyzing the complete genetic information, including potential virulence genes and other determinants with a negative impact on health, allows for assessing the safe use of the product, for which whole-genome sequencing (WGS) of individual LAB strains can be employed. Genomic data can also be used to understand subtle differences in the strain level important for beneficial effects, or protect patents. Here, we propose that WGS-based bioinformatics analyses are an ideal and cost-effective approach for the initial in silico microbial risk evaluation, while the technique may also increase our understanding of LAB strains for food safety and probiotic property evaluation.

Gut health benefit and application of postbiotics in animal production

Gut homeostasis is of importance to host health and imbalance of the gut usually leads to disorders or diseases for both human and animal. Postbiotics have been applied in manipulating of gut health, and utilization of postbiotics threads new lights into the host health. Compared with the application of probiotics, the characteristics such as stability and safety of postbiotics make it a potential alternative to probiotics. Studies have reported the beneficial effects of components derived from postbiotics, mainly through the mechanisms including inhibition of pathogens, strengthen gut barrier, and/or regulation of immunity of the host. In this review, we summarized the characteristics of postbiotics, main compounds of postbiotics, potential mechanisms in gut health, and their application in animal production.

The Anti-Cancer Potential of Heat-Killed Lactobacillus brevis KU15176 upon AGS Cell Lines through Intrinsic Apoptosis Pathway

Recent research has focused on the anti-cancer properties of Lactobacillus strains isolated from fermented foods. Their anti-cancer effects are caused by the apoptosis induction in cancer cells. However, sepsis, which can occur when cancer patients consume living organisms, can cause serious conditions in patients with reduced immunity because of cancer. Therefore, this study was conducted using heat-killed Lactobacillus brevis KU15176 (KU15176). To determine the relationship between inflammation and cancer, the anti-inflammatory effect of KU15176 was evaluated using a nitric oxide (NO) assay. Then, 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay was conducted to select cancer cells that showed the anti-proliferative effect of KU15176. Next, reverse transcription-polymerase chain reaction (RT-PCR), 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and caspase colorimetric assay were performed. As a result, it was confirmed that KU15176 could cause the increasing expression of apoptosis-related genes (Bax, caspase-3, and caspase-9), DNA breakage, effective apoptosis rate, and increased caspase activity in the human stomach adenocarcinoma (AGS) gastric cancer cell line. In conclusion, these results suggest a potential prophylactic effect of KU15176 against cancer.

Lacticaseibacillus rhamnosus: A Suitable Candidate for the Construction of Novel Bioengineered Probiotic Strains for Targeted Pathogen Control

Probiotics, with their associated beneficial effects, have gained popularity for the control of foodborne pathogens. Various sources are explored with the intent to isolate novel robust probiotic strains with a broad range of health benefits due to, among other mechanisms, the production of an array of antimicrobial compounds. One of the shortcomings of these wild-type probiotics is their non-specificity. A pursuit to circumvent this limitation led to the advent of the field of pathobiotechnology. In this discipline, specific pathogen gene(s) are cloned and expressed into a given probiotic to yield a novel pathogen-specific strain. The resultant recombinant probiotic strain will exhibit enhanced species-specific inhibition of the pathogen and its associated infection. Such probiotics are also used as vehicles to deliver therapeutic agents. As fascinating as this approach is, coupled with the availability of numerous probiotics, it brings a challenge with regard to deciding which of the probiotics to use. Nonetheless, it is indisputable that an ideal candidate must fulfil the probiotic selection criteria. This review aims to show how Lacticaseibacillus rhamnosus, a clinically best-studied probiotic, presents as such a candidate. The objective is to spark researchers’ interest to conduct further probiotic-engineering studies using L. rhamnosus, with prospects for the successful development of novel probiotic strains with enhanced beneficial attributes.

Gastrointestinal Microbiome and Neurologic Injury

Communication between the enteric nervous system (ENS) of the gastrointestinal (GI) tract and the central nervous system (CNS) is vital for maintaining systemic homeostasis. Intrinsic and extrinsic neurological inputs of the gut regulate blood flow, peristalsis, hormone release, and immunological function. The health of the gut microbiome plays a vital role in regulating the overall function and well-being of the individual. Microbes release short-chain fatty acids (SCFAs) that regulate G-protein-coupled receptors to mediate hormone release, neurotransmitter release (i.e., serotonin, dopamine, noradrenaline, γ-aminobutyric acid (GABA), acetylcholine, and histamine), and regulate inflammation and mood. Further gaseous factors (i.e., nitric oxide) are important in regulating inflammation and have a response in injury. Neurologic injuries such as ischemic stroke, spinal cord injury, traumatic brain injury, and hemorrhagic cerebrovascular lesions can all lead to gut dysbiosis. Additionally, unfavorable alterations in the composition of the microbiota may be associated with increased risk for these neurologic injuries due to increased proinflammatory molecules and clotting factors. Interventions such as probiotics, fecal microbiota transplantation, and oral SCFAs have been shown to stabilize and improve the composition of the microbiome. However, the effect this has on neurologic injury prevention and recovery has not been studied extensively. The purpose of this review is to elaborate on the complex relationship between the nervous system and the microbiome and to report how neurologic injury modulates the status of the microbiome. Finally, we will propose various interventions that may be beneficial in the recovery from neurologic injury.

Inflammatory Bowel Disease Therapeutics: A Focus on Probiotic Engineering

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of gastrointestinal (GI) tract with dysregulated mucosal immune functions and disturbed commensal ecosystem of the intestinal lumen. IBD is categorized into two major subsets: Crohn's disease (CD) and ulcerative colitis (UC). Though advent of biologics has shifted the treatment with relatively longer remission compared to small molecule pharmaceuticals, patients still suffer from long-term complications. Since gut-microbiome is now accepted as another human organ holding potential for long-lasting human health, probiotics, and its engineering hold great promises to treat several previously untreatable chronic inflammatory conditions including IBD. Several emerging biological engineering tools have unlimited potential to manipulate probiotic bacterial system. These can produce useful therapeutic biologics with a goal to either ameliorate and/or treat previously untreatable chronic inflammatory conditions. As gut-microbiome is diverse and vary in different ethnic, geographic, and cultural human population, it will be important to develop vision for personalized probiotic treatment and develop the technology thereof to make personalized probiotic options a reality. The aim of this review paper is to present an overview of the current knowledge on both pharmacological and nonpharmacological IBD treatment modalities with a special emphasis on probiotic strains that are developed through the probiotic engineering. These engineered probiotics contain the most anti-inflammatory cytokines found within the human immune response and are currently being used to treat the intestinal inflammation in IBD for the IBD treatment.

Role of Probiotics in the Management of COVID-19: A Computational Perspective

Coronavirus disease 2019 (COVID-19) was declared a pandemic at the beginning of 2020, causing millions of deaths worldwide. Millions of vaccine doses have been administered worldwide; however, outbreaks continue. Probiotics are known to restore a stable gut microbiota by regulating innate and adaptive immunity within the gut, demonstrating the possibility that they may be used to combat COVID-19 because of several pieces of evidence suggesting that COVID-19 has an adverse impact on gut microbiota dysbiosis. Thus, probiotics and their metabolites with known antiviral properties may be used as an adjunctive treatment to combat COVID-19. Several clinical trials have revealed the efficacy of probiotics and their metabolites in treating patients with SARS-CoV-2. However, its molecular mechanism has not been unraveled. The availability of abundant data resources and computational methods has significantly changed research finding molecular insights between probiotics and COVID-19. This review highlights computational approaches involving microbiome-based approaches and ensemble-driven docking approaches, as well as a case study proving the effects of probiotic metabolites on SARS-CoV-2.

Antibiotic susceptibility of Lactobacillus plantarum strains, isolated from katak

Several Lactobacillus species are accepted as microorganisms with Qualified Presumption of Safety (QPS) in the EFSA’s list. One of them, Lactobacillus plantarum is a widely distributed species with a proven probiotic potential and technological relevance. In addition, every strain must complete several requirements, before implementation. Antibiotic susceptibility is one of EFSA’s important criteria regarding the safety of probiotics. The reason is to avoid any possibility of antibiotic resistance genes transfer to opportunistic pathogens in the gut. In the present study 14 Lactobacillus plantarum strains were assessed for susceptibility to 21 antibiotics from different groups. A high number of resistant strains was determined toward 12 antibiotics (penicillins – penicillin, piperacillin; IIIth generation cephalosporins – cefotaxime, ceftriaxone, ceftazidime; glycopeptides – vancomycin; tetracyclines – tetracycline; aminoglycosides – gentamicin; macrolides – clarithromycin; quinolones – nalidixic acid, ciprofloxacin, levofloxacin). Concerning the other tested antibiotics, strain-specific antibiotic-sensitivity patterns were observed. Antibiotic resistance was also discussed as an advantage in the selection of probiotic strains, however only when it is not transferable. Estimated susceptibility patterns of some of tested candidate probiotic strains are also important, considering the use of the latter as agents accompanying antibiotic therapy

Microbiota shaping — the effects of probiotics, prebiotics, and fecal microbiota transplant on cognitive functions: A systematic review

BACKGROUND

Dementia is a chronic progressive neurological disease affecting millions of people worldwide, and represents a relevant economic burden for healthcare systems. Although its pathogenesis is still unknown, recent findings have reported that a dysregulated gut-brain axis communication, a fundamental relationship mediated by several host and microbial molecules, is associated with cognitive disorders. In addition, gut microbiota manipulation reduces neuroinflammation, improving cognitive function by restoring the functional gut-brain axis.

AIM

To better define the effects of probiotics, prebiotics, synbiotics, and fecal microbiota transplant (FMT) on cognitive function.

METHODS

We performed a literature search of human randomized clinical trials to examine the effects of the administration of probiotics, prebiotics, synbiotics, or FMT on cognition outcomes in healthy or sick people of every age, sex, and nationality. We systematically searched Embase, Medline/PubMed, Cochrane Library, central and clinicaltrials.gov databases with a combination of comprehensive terms related to cognition and gut microbiota manipulation. Then we carefully reviewed and synthesized the data by type of study design and setting, characteristics of the studied population, kind of intervention (strain type or mixture type, dosage, and frequency of administration), control treatment, inclusion and exclusion criteria, follow-up duration, and cognitive or memory outcomes.

RESULTS

After examining the titles and abstracts, the initial literature screening identified 995 articles, but we added 23 papers in our systematic review. The analyses of these selected studies highlighted that both probiotic supplementation and FMT improved cognitive function regardless of the type and posology of administration and the adopted cognitive tests and questionnaires. We found that most of the studies conducted in healthy people showed a significant positive effect of the intervention on at least one of the performed cognitive tests. Regarding unhealthy subjects, while FMT and especially probiotic administration had multiple beneficial effects on different cognitive functions, supplementation with prebiotics did not provide any cognitive improvement.

CONCLUSION

Probiotic supplementation and FMT may represent a promising strategy to restore gut eubiosis and enhance the cognitive functions of healthy people and patients with neurological disorders.

Invasive Infections Associated with the Use of Probiotics in Children: A Systematic Review

Although the effectiveness of probiotics has only been proven in specific conditions, their use in children is massively widespread because of their perception as harmless products. Recent evidence raises concerns about probiotics' safety, especially but not only in the paediatric population due to severe opportunistic infections after their use. This review aimed at summarising available case reports on invasive infections related to probiotics' use in children. For this purpose, we assessed three electronic databases to identify papers describing paediatric patients with documented probiotic-derived invasive infections, with no language restrictions. A total of 49 case reports from 1995 to June 2021 were identified. The infections were caused by Lactobacillus spp. (35%), Saccharomyces spp. (29%), Bifidobacterium spp. (31%), Bacillus clausii (4%), and Escherichia coli (2%). Most (80%) patients were younger than 2 years old and sepsis was the most observed condition (69.4%). All the patients except one had at least one condition facilitating the development of invasive infection, with prematurity (55%) and intravenous catheter use (51%) being the most frequent. Three (6%) children died. Given the large use of probiotics, further studies aiming at evaluating the real incidence of probiotic-associated systemic infections are warranted.

Beneficial Effects of Plant Extracts and Bioactive Food Components in Childhood Supplementation

The pivotal role of childhood nutrition has always roused a growing interest from the scientific community. Plant extracts and bioactive dietary components play a significant role in the maintenance of human health and wellness, with the potential to modulate risk factors and manage symptoms for a large number of common childhood disorders such as memory impairment, respiratory illnesses, gastrointestinal disorders, metabolic derangements, and pathologies related to the oral cavity. This review is designed to highlight the health benefits of botanical extracts and bioactive dietary components in children as evidenced by clinical trials, considering their safety with regards to childhood sensibilities. The supplementation of children with the herbal extracts or bioactive components mentioned in this review leads to the conclusion that they are useful for treating various ailments, with no serious adverse events being reported. However, for the limited number of investigations specifically focused on the safety of such products in children, time is needed to expand the literature data covering the safety of childhood supplementation with botanical extract and bioactive food components.

Probiotics-Live Biotherapeutics: a Story of Success, Limitations, and Future Prospects-Not Only for Humans

In livestock production, lactic acid bacteria (LAB) represent the most widespread microorganisms used as probiotics. For such critical use, these bacteria must be correctly identified and characterized to ensure their safety and efficiency. Recently, probiotics have become highly recognized as supplements for humans and in particular for animals because of their beneficial outcome on health improvement and well-being maintenance. Various factors, encompassing dietary and management constraints, have been demonstrated to tremendously influence the structure, composition, and activities of gut microbial communities in farm animals. Previous investigations reported the potential of probiotics in animal diets and nutrition. But a high rate of inconsistency in the efficiency of probiotics has been reported. This may be due, in a major part, to the dynamics of the gastrointestinal microbial communities. Under stressing surroundings, the direct-fed microbials may play a key role as the salient limiting factor of the severity of the dysbiosis caused by disruption of the normal intestinal balance. Probiotics are live microorganisms, which confer health benefits on the host by positively modifying the intestinal microflora. Thus, the aim of this review is to summarize and to highlight the positive influence of probiotics and potential probiotic microbe supplementation in animal feed with mention of several limitations.

Immuno-stimulatory effect and toxicology studies of salt pan bacteria as probiotics to combat shrimp diseases in aquaculture

The shrimp aquaculture industry has experienced serious economic losses due to diseases caused by Vibrio species. The application of antibiotics to combat diseases has led to environmental hazards, antibiotic-resistance in pathogens and accumulation of antibiotics in tissues. This study explores the use of probiotics as an alternative to antibiotics. A probiotic consortium SFSK4 (comprising salt pan bacteria Bacillus licheniformis TSK71, Bacillus amyloliquefaciens SK27, Bacillus subtilis SK07, Pseudomonas sp. ABSK55) was used as a water additive during shrimp culture. It significantly increased shrimp (Litopenaeus vannamei) immunity i.e. total hemocyte count, phagocytosis, total plasma protein, respiratory burst and bactericidal activity as compared to the control. It also stimulated the phenoloxidase activity by two-fold. Proteomic analysis revealed the differential expression of 50 immune proteins (39 up-regulated and 11 down-regulated) in SFSK4 treated shrimps. Four major immune modulation proteins viz. Caspase2, GTPase activating protein, Hemocyanin and Glucan pattern-recognition lipoprotein involved in cell mediated immune response were identified in SFSK4 treated shrimp hemolymph. SFSK4 decreased shrimp mortality by more than 50% against pathogens. Toxicology studies revealed that administration of the highest dose of probiotic (10¹² CFU/mL) showed no adverse effect on shrimp survival (LC₅₀ analysis) and neither exhibited cytotoxicity. Genotoxicity study confirmed that the probiotic did not cause DNA damage in shrimps. The findings suggest that the probiotic SFSK4 is an eco-friendly water additive to enhance shrimp immunity against diseases in aquaculture, which could help curtail environmental hazards as an effective alternative to antibiotics.

Role of probiotics in prevention and treatment of enteric infections: a comprehensive review

Microorganisms that inhabits human digestive tract affect global health and enteric disorders. Previous studies have documented the effectiveness and mode of action of probiotics and classified as human-friendly biota and a competitor to enteric pathogens. Statistical studies reported more than 1.5 billion cases of gastrointestinal infections caused by enteric pathogens and their long-term exposure can lead to mental retardation, temporary or permanent physical weakness, and leaving the patient susceptible for opportunistic pathogens, which can cause fatality. We reviewed previous literature providing evidence about therapeutic approaches regarding probiotics to cure enteric infections efficiently by producing inhibitory substances, immune system modulation, improved barrier function. The therapeutic effects of probiotics have shown success against many foodborne pathogens and their therapeutic effectiveness has been exponentially increased using genetically engineered probiotics. The bioengineered probiotic strains are expected to provide a better and alternative approach than traditional antibiotic therapy against enteric pathogens, but the novelty of these strains also raise doubts about the possible untapped side effects, for which there is a need for further studies to eliminate the concerns relating to the use and safety of probiotics. Many such developments and optimization of the classical techniques will revolutionize the treatments for enteric infections.

Assessment of the Safety of Lactobacillus casei IMV B-7280 Probiotic Strain on a Mouse Model

Probiotics, in particular Lactobacillus (lactic acid bacteria, LAB) strains, are widely used in clinical practice. Despite that these probiotics have GRAS (generally regarded as safe) and qualified presumption of safety (QPS) statuses, the safety of particular strains still needs to be thoroughly studied. The aim of the study was to evaluate the safety of Lact. casei IMV B-7280 strain by investigating toxicity and the effects on gut microbiota in experimental animal model. Male BALB/c mice (7-8 weeks, weight 20-24 g) were treated with amounts of Lact. casei IMV B-7280 strain: 5 × 10⁶, 5 × 10⁸, or 5 × 10⁹ CFU/animal once per day during 7 days, or in the amount of 1 × 10¹⁰ CFU/animal once per day during 3 days (most of the proposed probiotic doses for humans-from 10⁸ to 10⁹ CFU) and monitored during 14 days. Blood tests and serum biochemistry were conducted; the cecal content from mice of the experimental and control groups were freshly collected and analyzed. At the end of the experiments (15th day), the presence of LAB in the heart, liver, kidney, and mesenteric lymph nodes and peripheral blood was determined; histology of the brain, liver, heart, fragments of the small and large intestine, and mesenteric lymph nodes was conducted. Survival rate of BALB/c mice treated with Lact. casei IMV B-7280 strain in different concentrations in toxicity experiments during 14 days was 100%. We observed no signs of toxicity as changes in gait, lethargy, sleep, somatomotor activity as well as changes in fur, eyes, skin and mucous membranes, tremors, behavior pattern, convulsions, salivation, diarrhea, and local injuries in mice from all experimental groups. After administration of probiotic strain, the number of opportunistic bacteria in cecal contents, such as Staphylococcus spp., Candida spp., Pseudomonas spp., and total aerobic and optionally anaerobic bacteria decreased compared to controls; the population of beneficial bacteria such as lactobacilli increased in cecal contents of these mice. LAB were not detected in the peripheral blood, heart, liver, kidneys, and mesenteric lymph nodes after administration of this strain to intact mice. Lact. casei IMV B-7280 strain is safe at dose up to 10¹⁰ CFU/animal during 3- and 7-day oral administration to mice and has a positive effect on the gut microbiota composition; it could be potentially considered as safe probiotic for humans.

Therapeutic modulation methods of gut microbiota and gut-liver axis

Liver diseases are considered global health problems that cause more than 1 million deaths each year. Due to the increase in the prevalence of liver diseases worldwide, studies on different treatment methods have increased. Some of these methods is diagnostic and therapeutic applications based on the examination of the intestinal and intestinal microbiota. In this study, research articles, systematic review and review in the literature were examined in order to determine gut-liver axis relationship and treatment methods for liver diseases with gut modulation methods. Studies related to the subject have been searched in Google Scholar and Pubmed databases. The keywords "liver disease" and "gut-liver axis" and "microbiota" and "gut modulation methods" or "probiotic" or "prebiotic" or "symbiotic" or "antibiotic" or "bile acid regulation" or "adsorbent" or "fecal microbiota transplantation" were used in the searches. Improvements have been achieved in biomarkers of liver diseases by providing intestinal modulation with probiotic, prebiotic, symbiotic, antibiotic and adsorbents applications, bile acid regulation and fecal microbiota transplantation. In the results of experimental and clinical studies, it was seen that the therapeutic potential of the treatments performed by applying probiotics, prebiotics and symbiotics was higher.

Investigation of Antibacterial Activity and Probiotic Properties of Strains Belonging to Lactobacillus and Bifidobacterium Genera for Their Potential Application in Functional Food and Feed Products

For novel food/feed product formulation, the selection of the right culture with probiotic properties is essential. The purpose of this research was to evaluate antibacterial activity and probiotic features of Lactobacillus and Bifidobacterium spp. for its potential application in functional food/feed products as supplement. The evaluation of antibacterial activities was carried out by agar diffusion assay and broth inhibition assay methods against twelve pathogenic strains belonging to Staphylococcus aureus, Escherichia coli, Staphylococcus chromogenes, and Staphylococcus hyicus species. Metabolites produced by Lactobacillus paracasei subsp. paracasei DSM 20020, L. paracasei subsp. paracasei DSM 4905, and L. gasseri DSM 20077 inhibited the growth of all tested pathogens. The strains were characterized in vitro for their probiotic characteristics such as resistance to low pH and bile salts, antibiotic sensitivity by gradient diffusion using MIC Test Strips, autoaggregation and coaggregation assay with E. coli DSM 27503, and antioxidant activity by 1-diphenyl-2-picrylhydrazyl (DPPH) and 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. The results demonstrated that tested probiotic properties varied among the strains. Lactobacillus spp. tolerated pH 3 for 4 h, while 8 of 14 strains survived 4 h in pH 2. Most of tested strains were able to tolerate 0.3% bile salts for 4 h. All tested strains were sensitive to ampicillin. No gelatinase and hemolytic activities were detected. These results suggest Lactobacillus acidophilus DSM 20079, Bifidobacterium pseudolongum DSM 20099, and Bifidobacterium animalis DSM 20105 as probiotic candidates for the development of functional food/feed.

Update on Strategies of Probiotics for the Prevention and Treatment of Colorectal Cancer

In recent years, with the further research on probiotics, probiotics may become an indispensable part in the prevention and treatment of colorectal cancer (CRC) in the future. As one of the most common cancer, the incidence of CRC is still rising in developing countries. Nowadays, there are lacking in prevention methods with low side effect. Surgery and chemotherapy, as the main treatment of CRC, bring many complications and affect the quality of life of patients. Probiotics has provided new ideas to solve these problems. Probiotics have anti-inflammatory, immune-enhancing, tumor-suppressing and other beneficial effects. Probiotics may provide some safe and effective prevention strategies for CRC. In addition, probiotics can also reduce the complications of surgery and chemotherapy, and improve the effectiveness of chemotherapy. Target administration with probiotics or probiotics cooperated with TRAIL to treat CRC. This article aims to review the mechanisms of probiotics for the prevention and treatment of CRC, as well as specific ways to use probiotics, in order to provide more new strategies for the prevention and treatment of CRC in the future, and reduce the incidence of and improve the quality of life of patients.

Update of Probiotics in Human World: A Nonstop Source of Benefactions till the End of Time

Lactic acid bacteria (LAB) are known for their biotechnological potential. Moreover, LAB are distinguished by amazing criteria: Adjusting the intestinal environment, inhibiting pathogenic microbes in the gastrointestinal tract, ability to reduce pathogen adhesion activity, improving the balance of the microbiota inside the intestine, capabilities of regulating intestinal mucosal immunity, and maintaining intestinal barrier function. The escalating number of research and studies about beneficial microorganisms and their impact on promoting health has attracted a big interest in the last decades. Since antiquity, various based fermented products of different kinds have been utilized as potential probiotic products. Nevertheless, the current upsurge in consumers' interest in bioalternatives has opened new horizons for the probiotic field in terms of research and development. The present review aims at shedding light on the world of probiotics, a continuous story of astonishing success in various fields, in particular, the biomedical sector and pharmaceutical industry, as well as to display the importance of probiotics and their therapeutic potential in purpose to compete for sturdy pathogens and to struggle against diseases and acute infections. Shadows and future trends of probiotics use are also discussed.

Pilot Study of Probiotic Supplementation on Uremic Toxicity and Inflammatory Cytokines in Chronic Kidney Patients

Background:

Bacterial metabolism contributes to the generation of uremic toxins in patients with chronic kidney disease (CKD). It has been investigated the use of probiotics in the reduction of uremic toxins intestinal production.

Objective:

The aim of this pilot study was to evaluate the effect of probiotic supplementation on reducing the production of uremic toxins and the inflammatory profile of CKD patients.

Methods:

We performed a randomized, blind, placebo-controlled, crossover study on patients with CKD stages 3 and 4. The intervention was a probiotic formulation composed of Lactobacillus acidophilus strains given orally three times a day for 3 months. Changes in uremic toxins (p-Cresylsulfate and Indoxyl Sulfate) and serum inflammatory cytokines were the primary endpoints.

Results:

Of the 44 patients randomized, 25 completed the study (mean age 51 ± 9.34, 64% female, mean eGFR 36 ± 14.26 mL/min/1.73m², mean BMI 28.5 ± 5.75 kg/m²). At 3 months, there were no significant changes in any of the studied biomarkers including p-cresylsulfate (p = 0.57), Indoxyl sulfate (p = 0.08) and interleukin-6 (p = 0.55).

Conclusion:

Lactobacillus acidophilus strains given as probiotic were not able to reduce serum levels of uremic toxins and biomarkers of inflammation in CKD patients in stage 3 and 4.

Saccharomyces cerevisiae-Based Probiotics as Novel Antimicrobial Agents to Prevent and Treat Vaginal Infections

Vaginal infections affect 70% of women during their lifetimes and account for millions of annual doctors’ visits. These infections are predominantly represented by vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV). Although standard antimicrobial agents remain the major strategy for the prevention and treatment of vaginal infections, both VVC and BV are difficult to treat due to high rates of resistance and recurrence, high probability of complications, and negative effects on the vaginal microbiota. This review focuses on a new approach of yeast-based probiotics for the prevention and/or treatment of these common vaginal infections.

Microbial-Based and Microbial-Targeted Therapies for Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), including Crohn's disease, ulcerative colitis, and pouchitis, are chronic, relapsing intestinal inflammatory disorders mediated by dysregulated immune responses to resident microbiota. Current standard therapies that block immune activation with oral immunosuppressives or biologic agents are generally effective, but each therapy induces a sustained remission in only a minority of patients. Furthermore, these approaches can have severe adverse events. Recent compelling evidence of a role of unbalanced microbiota (dysbiosis) driving immune dysfunction and inflammation in IBD supports the therapeutic rationale for manipulating the dysbiotic microbiota. Traditional approaches using currently available antibiotics, probiotics, prebiotics, and synbiotics have not produced optimal results, but promising outcomes with fecal microbiota transplant provide a proof of principle for targeting the resident microbiota. Rationally designed oral biotherapeutic products (LBPs) composed of mixtures of protective commensal bacterial strains demonstrate impressive preclinical results. Resident microbial-based and microbial-targeted therapies are currently being studied with increasing intensity for IBD primary therapy with favorable early results. This review presents current evidence and therapeutic mechanisms of microbiota modulation, emphasizing clinical studies, and outlines prospects for future IBD treatment using new approaches, such as LBPs, bacteriophages, bacterial function-editing substrates, and engineered bacteria. We believe that the optimal clinical use of microbial manipulation may be as adjuvants to immunosuppressive for accelerated and improved induction of deep remission and as potential safer solo approaches to sustained remission using personalized regimens based on an individual patient's microbial profile.

Safety profiles of beneficial lactic acid bacteria isolated from dairy systems

This study aimed to assess the safety aspects of 15 lactic acid bacteria (LAB) strains previously isolated from a dairy environment with relation to their beneficial features. LAB strains were assessed using phenotypic methods according to their production of virulence factors at 25 °C and 37 °C, as well as by examining their potential resistance to 15 antibiotics. Polymerase chain reaction (PCR) was also used to identify the presence of 50 genes associated with virulence factors and antibiotic resistance in the strains. None of the strains presented hemolytic activity or the production of gelatinase, lipase, deoxyribonuclease, or the tested biogenic amines. Based on the disk diffusion assay, all strains were resistant to oxacillin and sulfa/trimethoprim. Further, some were resistant to gentamicin (14), clindamycin (11), vancomycin (9), rifampicin (8), erythromycin (5), tetracycline (4), ampicillin (2), and chloramphenicol (1); no strain was resistant to imipenem. Regarding virulence- and antibiotic-resistance-related genes, 19 out of 50 tested genes were present in some strains; there was a variable association of expression. Based on the obtained data, the isolates presented relatively safe characteristics and behavior, findings that should lead to further studies to assess their potential usage as beneficial cultures in the food industry.