Probiotics for infectious diseases: more drugs, less dietary supplementation

Antimicrobial Peptides and Their Mimetics: Promising Candidates of Next-Generation Therapeutic Agents Combating Multidrug-Resistant Bacteria

The increasing morbidity and mortality caused by multidrug-resistant bacteria alerts human beings to the fact that conventional antibiotics are no longer reliable and effective alternatives are imperatively needed. Owing to wide range of sources, diverse structures, and unique mode of action, antimicrobial peptides have been highly anticipated and extensively studied in recent years. Besides, the integration of artificial intelligence helps researchers gain access to the vast unexplored chemical space, which opens more opportunities for the optimization and design of novel structures. Moreover, Due to advances in chemistry and synthetic biology, researchers have also begun to focus on the potential of chemical mimetics of antimicrobial peptides. In this review, a comprehensive discussion about natural and synthesized antimicrobial peptides as well as their chemical mimetics is made, so as to provide a comprehensive summary of this field and inspire follow-up research.

The Interaction of Microbiome and Pancreas in Acute Pancreatitis

Acute pancreatitis (AP) is a common acute abdomen disease characterized by the pathological activation of digestive enzymes and the self-digestion of pancreatic acinar cells. Secondary infection and sepsis are independent prognosticators for AP progression and increased mortality. Accumulating anatomical and epidemiological evidence suggests that the dysbiosis of gut microbiota affects the etiology and severity of AP through intestinal barrier disruption, local or systemic inflammatory response, bacterial translocation, and the regulatory role of microbial metabolites in AP patients and animal models. Recent studies discussing the interactions between gut microbiota and the pancreas have opened new scopes for AP, and new therapeutic interventions that target the bacteria community have received substantial attention. This review concentrates on the alterations of gut microbiota and its roles in modulating gut-pancreas axis in AP. The potential therapies of targeting microbes as well as the major challenges of applying those interventions are explored. We expect to understand the roles of microbes in AP diagnosis and treatment.

Gut microbiota interacts with inflammatory responses in acute pancreatitis

Acute pancreatitis (AP) is one of the most common acute abdominal conditions, and its incidence has been increasing for years. Approximately 15-20% of patients develop severe AP (SAP), which is complicated by critical inflammatory injury and intestinal dysfunction. AP-associated inflammation can lead to the gut barrier and function damage, causing dysbacteriosis and facilitating intestinal microbiota migration. Pancreatic exocrine deficiency and decreased levels of antimicrobial peptides in AP can also lead to abnormal growth of intestinal bacteria. Meanwhile, intestinal microbiota migration influences the pancreatic microenvironment and affects the severity of AP, which, in turn, exacerbates the systemic inflammatory response. Thus, the interaction between the gut microbiota (GM) and the inflammatory response may be a key pathogenic feature of SAP. Treating either of these factors or breaking their interaction may offer some benefits for SAP treatment. In this review, we discuss the mechanisms of interaction of the GM and inflammation in AP and factors that can deteriorate or even cure both, including some traditional Chinese medicine treatments, to provide new methods for studying AP pathogenesis and developing therapies.

Clinical efficacy of probiotics in prevention of infectious diseases among hospitalized patients in ICU and non-ICU wards in clinical randomized trials: A systematic review

Background and Aims

The present study aimed to review probiotics' clinical efficacy in preventing infectious diseases among hospitalized patients in ICU and non-ICU wards.

Methods

A search of Medline, EMBASE, The Cochrane Library, Science Direct, Open Grey, and Google Scholar was conducted for eligible publications from 2002 to 2020 following the requirements outlined in the PRISMA guideline. The search strategy was based on the combination of the following terms: "probiotics," "prebiotics," "synbiotics," and "cross-infection." The logical operators "AND" (or the equivalent operator for the databases) and "OR" (e.g., probiotics OR prebiotics OR synbiotics) were used.

Results

The results indicated that the probiotic consumption caused a significant reduction in antibiotic-associated diarrhea (AAD) and Clostridioides difficile infection (CDI) in 2/8 randomized clinical trials (RCTs) investigating AAD/CDI. Also, 5/12 clinical trials highlighted the considerable effects of probiotics on the reduction or prevention of ventilator associated pneumoniae (VAP), so the mean prevalence of VAP was lower in the probiotic group than in the placebo group. The total rate of nosocomial infections among preterm infants was nonsignificantly higher in the probiotic group compared to the control group.

Conclusion

This systematic review shows that the administration of probiotics has moderate preventive or mitigating effects on the occurrence of VAP in ICU patients, CDI, AAD, and nosocomial infections among children. Consequently, applying antibiotics along with the proper probiotic species can be advantageous.

Microencapsulation for Food Applications: A Review

Food products contain various active ingredients, such as flavors, nutrients, unsaturated fatty acids, color, probiotics, etc., that require protection during food processing and storage to preserve their quality and shelf life. This review provides an overview of standard microencapsulation technologies, processes, materials, industrial examples, reasons for market success, a summary of recent applications, and the challenges in the food industry, categorized by active food ingredients: flavors, polyunsaturated fatty acids, probiotics, antioxidants, colors, vitamins, and others. We also provide a comprehensive analysis of the advantages and disadvantages of the most common microencapsulation technologies in the food industry such as spray drying, coacervation, extrusion, and spray cooling. This review ends with future perspectives on microencapsulation for food applications.

A FOUR PROBIOTIC PREPARATION FOR VENTILATOR-ASSOCIATED PNEUMONIA IN MULTI-TRAUMA PATIENTS: RESULTS OF A RANDOMIZED CLINICAL TRIAL

The role of probiotics for the prevention of ventilator-associated pneumonia remains inconclusive. Our aim was to assess the efficacy of a probiotics regimen for VAP prophylaxis in mechanically ventilated multi-trauma patients, intubated immediately after the injurious insult. In a randomized, placebo-controlled study enrolling multi-trauma patients, anticipated to require mechanical ventilation for more than 10 days were randomly assigned to receive prophylaxis either with a probiotic formula [n=59] or placebo [n=53]. The probiotic formula was a preparation of Lactobacillus acidophilus LA-5 (1.75 × 10⁹ cfu), L. plantarum (0.5 × 10⁹ cfu), B. lactis BB-12 (1.75 × 10⁹ cfu) and S. boulardii (1.5 × 10⁹ cfu) per sachet. Each patient received two sachets twice daily for 15 days; one through the nasogastric tube; and another spread on the oropharynx. The incidence of VAP was the primary endpoint. The incidence of other infections and sepsis and the duration of hospital stay were the secondary endpoints. Probiotics administration reduced notably the incidence of VAP [11.9% vs 28.3%, odds ratio 0.34, 95%CIs 0.13-0.92, p=0.034] and of sepsis [6.8% vs 24.5%, OR 0.22, 95% CIs 0.07-0.74, p=0.016]. Furthermore, probiotics prophylaxis decreases the time of stay in the intensive care unit (ICU) and of hospital stay. The prophylactic use of probiotics as a combination of enteral and topical application to oropharynx exerted a positive effect on the incidence of VAP and sepsis as well as on the ICU and total hospital stay in patients under protracted mechanical ventilation.

The probiotic supplementation role in improving the immune system among people with ulcerative colitis: a narrative review

OBJECTIVES

The purpose of this paper is to summarize the current evidence on probiotics' uses as an adjuvant for ulcerative colitis (UC) and provide an understanding of the effect of probiotics supplement on the immune system and inflammatory responses among UC patients and subsequent therapeutic benefits.

CONTENT

A narrative review of all the relevant published papers known to the author was conducted.

SUMMARY

UC is a chronic inflammatory bowel disease (IBD) that results in inflammation and ulceration of the colon and rectum. The primary symptoms of active disease are diarrhea, abdominal pain, and rectal bleeding. About 70% of the human immune system (mucosal-associated lymphoid tissue) originates in the intestine. Probiotics are live microorganisms that help in stabilizing the gut microbiota (nonimmunologic gut defense), restores normal flora, and enhance the humoral immune system. Probiotics especially Bifidobacterium, Saccharomyces boulardii, and lactic acid-producing bacteria have been used as an adjunct therapy for treating UC to ameliorate disease-related symptoms and reduce relapse rate. Probiotics, in general, modulate the immune system through their ability to enhance the mucosal barrier function, or through their interaction with the local immune system to enhance regulatory T cell responses, decrease the pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin 1 beta and increase anti-inflammatory factor interleukin 10.

OUTLOOK

More studies are needed to explore the properties of the various probiotic bacterial strains, their different uses, as well as the dosage of probiotics and duration for treating different disorders. Further clinical investigations on mechanisms of action and how probiotics modulate the immune system may lead to further advances in managing IBD.

The probiotic supplementation role in improving the immune system among people with ulcerative colitis: a narrative review

OBJECTIVES

The purpose of this paper is to summarize the current evidence on probiotics' uses as an adjuvant for ulcerative colitis (UC) and provide an understanding of the effect of probiotics supplement on the immune system and inflammatory responses among UC patients and subsequent therapeutic benefits.

CONTENT

A narrative review of all the relevant published papers known to the author was conducted.

SUMMARY

UC is a chronic inflammatory bowel disease (IBD) that results in inflammation and ulceration of the colon and rectum. The primary symptoms of active disease are diarrhea, abdominal pain, and rectal bleeding. About 70% of the human immune system (mucosal-associated lymphoid tissue) originates in the intestine. Probiotics are live microorganisms that help in stabilizing the gut microbiota (nonimmunologic gut defense), restores normal flora, and enhance the humoral immune system. Probiotics especially Bifidobacterium, Saccharomyces boulardii, and lactic acid-producing bacteria have been used as an adjunct therapy for treating UC to ameliorate disease-related symptoms and reduce relapse rate. Probiotics, in general, modulate the immune system through their ability to enhance the mucosal barrier function, or through their interaction with the local immune system to enhance regulatory T cell responses, decrease the pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin 1 beta and increase anti-inflammatory factor interleukin 10.

OUTLOOK

More studies are needed to explore the properties of the various probiotic bacterial strains, their different uses, as well as the dosage of probiotics and duration for treating different disorders. Further clinical investigations on mechanisms of action and how probiotics modulate the immune system may lead to further advances in managing IBD.

Targeted Therapeutic Strategies in the Battle Against Pathogenic Bacteria

The emergence and rapid spread of antibiotic resistance in pathogenic bacteria constitute a global threat for public health. Despite ongoing efforts to confront this crisis, the pace of finding new potent antimicrobials is far slower than the evolution of drug resistance. The abuse of broad-spectrum antibiotics not only accelerates the formation of resistance but also imposes a burden on the intestinal microbiota, which acts a critical role in human homeostasis. As such, innovative therapeutic strategies with precision are pressingly warranted and highly anticipated. Recently, target therapies have achieved some breakthroughs by the aid of modern technology. In this review, we provide an insightful illustration of current and future medical targeted strategies, including narrow-spectrum agents, engineered probiotics, nanotechnology, phage therapy, and CRISPR-Cas9 technology. We discuss the recent advances and potential hurdles of these strategies. Meanwhile, the possibilities to mitigate the spread of resistance in these approaches are also mentioned. Altogether, a better understanding of the advantages, disadvantages, and mechanisms of action of these targeted therapies will be conducive to broadening our horizons and optimizing the existing antibacterial approaches.

Combination of Enteral Nutrition and Probiotics Promote Recovery Following Ileal Pouch-Anal Anastomosis in Rats

Many patients with ulcerative colitis suffer from malnutrition and intestinal flora disorders, which affect the postoperative intestinal barrier function of the ileal pouch. This study aimed to investigate the effects of enteral nutrition combined with probiotics after ileal pouch-anal anastomosis in rats. Male Sprague-Dawley rats underent ileal pouch-anal anastomosis and were randomly assigned to a control group (standard rat chow), enteral nutrition group (short-peptide enteral nutrition), or probiotic nutrition group (short-peptide enteral nutrition and Lactobacillus acidophilus). The primary outcomes were a histological score and occludin levels in the ileal pouch. The secondary outcomes were nutritional status and fecal flora distribution. The histological scores in the control group were significantly higher than in the enteral nutrition and probiotic nutrition groups (P < 0.05), while occludin levels were significantly lower in the controls compared with the other two groups (P < 0.05). Serum total protein, albumin, transthyretin, and transferrin levels were significantly higher in the probiotic nutrition group, followed by the enteral nutrition and control groups (all P < 0.05). Total fecal flora, and Gram-positive and Gram-negative rods differed significantly among the groups (all P < 0.05), but there were no significant differences in Gram-positive or Gram-negative cocci (all P > 0.05). Enteral nutrition combined with probiotics can effectively protect the intestinal barrier function of the ileal pouch in rats, possibly via the stable distribution of the intestinal flora and good nutritional status.

A Tale of Two Ends: Repurposing Metallic Compounds from Anti-Tumour Agents to Effective Antibacterial Activity

The rise in antibiotic resistance coupled with the gap in the discovery of active molecules has driven the need for more effective antimicrobials while focusing the attention into the repurpose of already existing drugs. Here, we evaluated the potential antibacterial activity of one cobalt and two zinc metallic compounds previously reported as having anticancer properties. Compounds were tested against a range of Gram-positive and -negative bacteria. The determination of the minimum inhibitory and bactericidal concentrations (MIC/MBC) of the drugs were used to assess their potential antibacterial activity and their effect on bacterial growth. Motility assays were conducted by exposing the bacteria to sub-MIC of each of the compounds. The effect of sub-MIC of the compounds on the membrane permeability was measured by ethidium bromide (EtBr) accumulation assay. Cell viability assays were performed in human cells. Compound TS262 was the most active against the range of bacteria tested. No effect was observed on the motility or accumulation of EtBr for any of the bacteria tested. Cell viability assays demonstrated that the compounds showed a decrease in cell viability at the MIC. These results are promising, and further studies on these compounds can lead to the development of new effective antimicrobials.

Comparative evaluation of Lactobacillus strains with different adhesion ability on growth performance and immunomodulatory activity in broiler chickens

The study was designed to assess the effect of 2 Lactobacillus strains (Lactobacillus kefiri 1.3207 and Lactobacillus plantarum 1.2567) with different adherence ability on growth performance and immunomodulatory activity in broiler. The BW and FCR were higher in L. kefiri 1.3207 and L. plantarum 1.2567 groups compared to control group at 42 days of age, and BW of broilers in L. kefiri 1.3207 group was significantly higher than that in L. plantarum 1.2567 group. IgA and IgG contents and the spleen and bursa of Fabricius indices in significantly increased in the L. kefiri 1.3207 group, but not in the L. plantarum 1.2567-treated group. L. kefiri 1.3207 had more significant effect on growth performance, plasma IgA and IgG levels and immune organs indices because it had better adhesion ability.

Alternatives to Conventional Antibiotics in the Era of Antimicrobial Resistance

As more antibiotics are rendered ineffective by drug-resistant bacteria, focus must be shifted towards alternative therapies for treating infections. Although several alternatives already exist in nature, the challenge is to implement them in clinical use. Advancements within biotechnology, genetic engineering, and synthetic chemistry have opened up new avenues towards the search for therapies that can substitute for antibiotics. This review provides an introduction to the various promising approaches that have been adopted in this regard. Whilst the use of bacteriophages and antibodies has been partly implemented, other promising strategies, such as probiotics, lysins, and antimicrobial peptides, are in various stages of development. Propitious concepts such as genetically modified phages, antibacterial oligonucleotides, and CRISPR-Cas9 are also discussed.

Feasibility of a Lactobacillus casei Drink in the Intensive Care Unit for Prevention of Antibiotic Associated Diarrhea and Clostridium difficile

Background: Over 70% of patients are prescribed antibiotics during their intensive care (ICU) admission. The gut microbiome is dramatically altered early in an ICU stay, increasing the risk for antibiotic associated diarrhea (AAD) and Clostridium difficile infections (CDI). Evidence suggests that some probiotics are effective in the primary prevention of AAD and CDI. Aim: To demonstrate safety and feasibility of a probiotic drink in ICU patients. Methods: ICU patients initiated on antibiotics were recruited, and matched with contemporary controls. Study patients received two bottles daily of a drink containing 10 billion Lactobacillus casei which was bolused via feeding tube. Tolerance to probiotics and enteral nutrition, development of adverse events, and incidence of AAD was recorded. CDI rates were followed for 30 days post antibiotic treatment. Results: Thirty-two patients participated in the trial. There were no serious adverse events in the probiotic group, compared to three in the control group. AAD was documented in 12.5% of the probiotic group and 31.3% in the control group. One patient in the probiotic group developed CDI compared to three in the control group. Discussion: A probiotic containing drink can safely be delivered via feeding tube and should be considered as a preventative measure for AAD and CDI in ICU.

Sustainable farming of the mealworm Tenebrio molitor for the production of food and feed

The farming of edible insects is an alternative strategy for the production of protein-rich food and feed with a low ecological footprint. The industrial production of insect-derived protein is more cost-effective and energy-efficient than livestock farming or aquaculture. The mealworm Tenebrio molitor is economically among the most important species used for the large-scale conversion of plant biomass into protein. Here, we review the mass rearing of this species and its conversion into food and feed, focusing on challenges such as the contamination of food/feed products with bacteria from the insect gut and the risk of rapidly spreading pathogens and parasites. We propose solutions to prevent the outbreak of infections among farmed insects without reliance on antibiotics. Transgenerational immune priming and probiotic bacteria may provide alternative strategies for sustainable insect farming.

Recipe for IBD: can we use food to control inflammatory bowel disease?

The mucosal immune system and the microbiota in the intestinal tract have recently been shown to play a key role in the pathogenesis of inflammatory bowel disease (IBD). Both of these can be influenced by food. Thus, we propose dietary intervention as a therapeutic option for IBD. In this review, we discuss the interaction of the intestinal mucosal immune system and the intestinal microbiota in the context of IBD. In addition, we discuss the impact of food components on immune responses in IBD. Finally, we address the current evidence of how this interaction (i.e., immune system-microbiota) can be modulated by food components, pre/probiotics, and fecal microbiota transplantation (FMT) and how these approaches can support intestinal homeostasis. By gathering the vast amount of literature available on the impact of food on IBD, we aim to distinguish between scientifically sound data and theories, which have not been included in this review.

Probiotic Enterococcus mundtii Isolate Protects the Model Insect Tribolium castaneum against Bacillus thuringiensis

Enterococcus mundtii strains isolated from the larval feces of the Mediterranean flour moth Ephestia kuehniella show antimicrobial activity against a broad spectrum of Gram-positive and Gram-negative bacteria. The in vitro probiotic characterization of one isolate revealed a high auto-aggregation score, a hydrophilic cell surface, tolerance for low pH, no hemolytic activity, and susceptibility to all tested antibiotics. We used the red flour beetle Tribolium castaneum, an established model organism, for the in vivo characterization of one probiotic E. mundtii isolate from E. kuehniella larvae. Tribolium castaneum larvae were fed orally with the probiotic isolate or the corresponding supernatant and then infected with either the entomopathogen Bacillus thuringiensis or Pseudomonas entomophila. Larvae exposed to the isolate or the supernatant showed increased survival following infection with B. thuringiensis but not P. entomophila. Heat treatment or treatment with proteinase K reduced the probiotic effect of the supernatant. However, the increased resistance attracts a fitness penalty manifested as a shorter lifespan and reduced fertility. T. castaneum has, pending on further research, the potential as an alternative model for the pre-screening of probiotics.

In vitro gene expression-coupled bacterial cell chip for screening species-specific antimicrobial enzymes

Targeting infectious bacterial pathogens is important for reducing the evolution of antibiotic-resistant bacteria and preserving the endogenous human microbiome. Cell lytic enzymes including bacteriophage endolysins, bacterial autolysins, and other bacteriolysins are useful antibiotic alternatives due to their exceptional target selectivity, which may be used to lysins rapidly kill target bacteria and their high specificity permit the normal commensal microflora to be left undisturbed. Genetic information of numerous lysins is currently available, but the identification of their antimicrobial function and specificity has been limited because most lysins are often poorly expressed and exhibit low solubilities. Here, we report the development of bacterial cell chip for rapidly accessing the function of diverse genes that are suggestive of encoding lysins. This approach can be used to evaluate rapidly the species-specific antimicrobial activity of diverse lysins synthesized from in vitro transcription and translation (TNT) of plasmid DNA. In addition, new potent lysins can be assessed that are not expressed in hosts and display low solubility. As a result of evaluating the species-specific antimicrobial function of 11 (un)known lysins with an in vitro TNT-coupled bacterial cell chip, a potent recombinant lysin against Staphylococcus strains, SA1, was identified. The SA1 was highly potent against not only S. aureus, but also both lysostaphin-resistant S. simulans and S. epidermidis cells. To this end, the SA1 may be applicable to treat both methicillin-resistant S. aureus (MRSA) and lysostaphin-resistant MRSA mutants. Biotechnol. Bioeng. 2017;114: 1648-1657. © 2017 Wiley Periodicals, Inc.

Inhibitory effect of Lactobacillus plantarum and Lb. fermentum isolated from the faeces of healthy infants against nonfermentative bacteria causing nosocomial infections

Nosocomial infection constitutes a major public health problem worldwide. Increasing antibiotic resistance of pathogens associated with nosocomial infections has also become a major therapeutic challenge for physicians. Thus, development of alternative treatment protocols, such as the use of probiotics, matters. The aim of this research was to determine the antagonistic properties of Lactobacillus plantarum and Lb. fermentum isolated from the faeces of healthy infants against nonfermentative bacteria causing nosocomial infections. One hundred five samples of nosocomial infections were collected and processed for bacterial isolation and antimicrobial susceptibility testing following standard bacteriologic techniques. The antibiotic susceptibility test was performed by the disk diffusion method, and antagonistic effect of Lactobacillus strains was investigated by well diffusion method. Of 105 samples, a total of 29 bacterial strains were identified as nonfermentative bacteria, including 17 Acinetobacter baumannii and 12 Pseudomonas aeruginosa. A. baumannii showed high resistance to tested antibiotics except ampicillin/sulbactam, and P. aeruginosa showed resistance to ampicillin/sulbactam and gentamicin and sensitive to amikacin and meropenem. Lb. plantarum had antagonistic properties against both A. baumannii and P. aeruginosa strains. Lb. plantarum had considerable effects on preventing the growth of A. baumannii and P. aeruginosa strains. However, further research is needed to better understanding of these effects on P. aeruginosa.

Gut microbiome, surgical complications and probiotics

The trigger for infectious complications in patients following major abdominal operations is classically attributed to endogenous enteral bacterial translocation, due to the critical condition of the gut. Today, extensive gut microbiome analysis has enabled us to understand that almost all "evidence-based" surgical or medical intervention (antibiotics, bowel preparation, opioids, deprivation of nutrition), in addition to stress-released hormones, could affect the relative abundance and diversity of the enteral microbiome, allowing harmful bacteria to proliferate in the place of depressed beneficial species. Furthermore, these bacteria, after tight sensing of host stress and its consequent humoral alterations, can and do switch their virulence accordingly, towards invasion of the host. Probiotics are the exogenously given, beneficial clusters of live bacteria that, upon digestion, seem to succeed in partially restoring the distorted microbial diversity, thus reducing the infectious complications occurring in surgical and critically ill patients. This review presents the latest data on the interrelationship between the gut microbiome and the occurrence of complications after colon surgery, and the efficacy of probiotics as therapeutic instruments for changing the bacterial imbalance.

Identification of a Peptide Produced by Bifidobacterium longum CECT 7210 with Antirotaviral Activity

Rotavirus is one of the main causes of acute diarrhea and enteritis in infants. Currently, studies are underway to assess the use of probiotics to improve rotavirus vaccine protection. A previous work demonstrated that the probiotic strain Bifidobacterium longum subsp. infantis CECT 7210 is able to hinder rotavirus replication both in vitro and in vivo. The present study takes a systematic approach in order to identify the molecule directly involved in rotavirus inhibition. Supernatant protease digestions revealed both the proteinaceous nature of the active substance and the fact that the molecule responsible for inhibiting rotavirus replication is released to the supernatant. Following purification by cationic exchange chromatography, active fractions were obtained and the functional compound was identified as an 11-amino acid peptide (MHQPHQPLPPT, named 11-mer peptide) with a molecular mass of 1.282 KDa. The functionality of 11-mer was verified using the synthesized peptide in Wa, Ito, and VA70 rotavirus infections of both HT-29 and MA-104 cell lines. Finally, protease activity was detected in B. longum subsp. infantis CECT 7210 supernatant, which releases 11-mer peptide. A preliminary identification of the protease is also included in the study.

Alternatives to antibiotics-a pipeline portfolio review

Antibiotics have saved countless lives and enabled the development of modern medicine over the past 70 years. However, it is clear that the success of antibiotics might only have been temporary and we now expect a long-term and perhaps never-ending challenge to find new therapies to combat antibiotic-resistant bacteria. A broader approach to address bacterial infection is needed. In this Review, we discuss alternatives to antibiotics, which we defined as non-compound approaches (products other than classic antibacterial agents) that target bacteria or any approaches that target the host. The most advanced approaches are antibodies, probiotics, and vaccines in phase 2 and phase 3 trials. This first wave of alternatives to antibiotics will probably best serve as adjunctive or preventive therapies, which suggests that conventional antibiotics are still needed. Funding of more than £1·5 billion is needed over 10 years to test and develop these alternatives to antibiotics. Investment needs to be partnered with translational expertise and targeted to support the validation of these approaches in phase 2 trials, which would be a catalyst for active engagement and investment by the pharmaceutical and biotechnology industry. Only a sustained, concerted, and coordinated international effort will provide the solutions needed for the future.

Probiotic-based strategies for therapeutic and prophylactic use against multiple gastrointestinal diseases

Probiotic bacteria offer a number of potential health benefits when administered in sufficient amounts that in part include reducing the number of harmful organisms in the intestine, producing antimicrobial substances and stimulating the body's immune response. However, precisely elucidating the probiotic effect of a specific bacterium has been challenging due to the complexity of the gut's microbial ecosystem and a lack of definitive means for its characterization. This review provides an overview of widely used and recently described probiotics, their impact on the human's gut microflora as a preventative treatment of disease, human/animal models being used to help show efficacy, and discusses the potential use of probiotics in gastrointestinal diseases associated with antibiotic administration.

Probiotic bacteria, B. longum and L. acidophilus inhibit infection by rotavirus in vitro and decrease the duration of diarrhea in pediatric patients

BACKGROUND AND OBJECTIVES

Evidence suggests that specific probiotics may be antagonistic to enteric pathogens and enhance immunity, and thus, provide a means of preventing or treating diarrheal diseases. In the present study, we aimed to evaluate the efficacy of probiotic strains isolated from Koreans for the treatment of viral gastroenteritis in young children and against rotavirus in vitro.

METHODS

In vitro antiviral activities of probiotic isolates on rotavirus infection were investigated in the Vero cell using a plaque reduction assay. Then several probiotic strains with the high antiviral activity were chosen for further clinical trials. Twenty-nine pediatric patients who presented with symptoms of viral gastroenteritis were enrolled in a double-blind trial and randomly assigned at admission to receive six probiotic strains (Bifidobacterium longum, B. lactis, Lactobacillus acidophilus, L. rhamnosus, L. plantarum, and Pediococcus pentosaceus) at a dose of 10(9) colony forming units/g or a comparable placebo twice daily for 1 week.

RESULTS AND CONCLUSIONS

Of the tested probiotic strains, B. longum isolated from an infant showed the greatest inhibitory effect and L. acidophilus showed the second-highest inhibitory effect. These probiotics significantly shortened the duration of diarrhea as compared with a placebo (6.1 ± 0.5 vs 7.2 ± 1.9, P = 0.030) and did not induce any adverse effects. Our findings suggest that the probiotic strains selected in the present study may be useful for the treatment of acute rotaviral gastroenteritis or as an alternative therapy without adverse effects.

Obesity, inflammation, and the gut microbiota

As the prevalence of obesity and associated disease continues to rise and concerns for the spiralling economic and social costs also escalate, innovative management strategies beyond primary prevention and traditional lifestyle interventions are urgently needed. The biological basis of disease is one avenue for further exploration in this context. Several key inflammatory markers have been consistently associated with both obesity and risk of adverse outcomes in obesity-associated diseases, which suggests that a persistent, low-grade, inflammatory response is a potentially modifiable risk factor. In this Review, we provide evidence supporting perturbation of the intestinal microbiota and changes in intestinal permeability as potential triggers of inflammation in obesity. Further characterisation of the mechanisms underpinning the triggers of such inflammatory responses in overweight and obese individuals could offer unique opportunities for intervention strategies to help ameliorate the risk of obesity-associated disease.

Pre-treatment with probiotics prolongs survival after experimental infection by multidrug-resistant Pseudomonas aeruginosa in rodents: an effect on sepsis-induced immunosuppression

Based on several randomised clinical studies indicating benefit from oral probiotic intake for the prevention of hospital-acquired infections in critically ill patients, this study aimed to explain the mechanism of action of probiotics for the prevention of lethal experimental infection by multidrug-resistant (MDR) Pseudomonas aeruginosa. Experiments using an Escherichia coli strain susceptible to all antimicrobials were also conducted. C57BL/6 mice were pre-treated intraperitoneally with sterile water for injection or Lactobacillus plantarum. Survival was recorded and mice were sacrificed for measurement of apoptosis and tissue bacterial overgrowth and for isolation and culture of splenocytes for cytokine production. Experiments were repeated after pre-treatment with a commercial preparation of four probiotics (L. plantarum, Lactobacillus acidophilus, Saccharomyces boulardii and Bifidobacterium lactis; LactoLevure(®)). Peripheral blood mononuclear cells (PBMCs) of healthy volunteers were stimulated by heat-killed P. aeruginosa following pre-treatment with medium or probiotics. Pre-treatment with L. plantarum significantly prolonged survival after challenge by either MDR P. aeruginosa (66.7% vs. 31.3%; P=0.026) or E. coli (56.0% vs. 12.0%, P=0.003). Survival benefit was even more pronounced when mice were pre-treated with LactoLevure(®). Tissue bacterial outgrowth and apoptosis of white blood cells and splenocytes were not altered. TNFα and IL-10 production by splenocytes of mice pre-treated with probiotic was increased and IFNγ production was decreased. Pre-treatment with LactoLevure(®) restored production of IL-17. Stimulation of human PBMCs after probiotic pre-treatment was accompanied by reduced gene expression of SOCS3. The results suggest that the protective effect of probiotics is mediated through prevention of sepsis-induced immunosuppression.

Effect of early enteral nutrition with Bifico on levels of inflammatory mediators in plasma of patients with severe acute pancreatitis

AIM: To explore the effect of early enteral nutrition combined with probiotic treatment (Bifico) on the levels of inflammatory mediators in plasma of patients with severe acute pancreatitis (SAP).

METHODS: Eighty patients diagnosed with SAP between January 2006 and October 2013 at our hospital were included. They were given parenteral nutrition (PN group), enteral nutrition (EN group) or EN and probiotics (P + EN group). Plasma levels of interleukin-8 (IL-8), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP) and lactate dehydrogenase (LDH), white blood cell count, serum amylase, and plasma lipase were measured 1 d before and 7 d and 14 d after treatment. Hospitalization time and gastrointestinal function score were also recorded and compared.

RESULTS: After treatment, white blood cell count, serum amylase, plasma lipase and IL-8, CRP and LDH, and gastrointestinal function score were decreased in all the three groups (P < 0.05), while TNF-α in the PN group had no significant change between before and after treatment (F = 0.793, 0.745; P = 0.854, 0.772). White blood cell count, amylase and lipase levels after treatment in the P + EN group were significantly lower than those in the PN group and EN group (4.9 × 10⁹/L ± 2.4 × 10⁹/L vs 9.6 × 10⁹/L ± 3.0 × 10⁹/L vs 5.3 × 10⁹/L ± 2.7 × 10⁹/L; 197 U/L ± 50 U/L vs 297 U/L ± 77 U/L vs 253 U/L ± 63 U/L; 297 U/L ± 72 U/L vs 724 U/L ± 103 U/L vs 323 U/L ± 74 U/L; F = 5.346, 5.753; P = 0.023, 6.556, 0.022, 0.029). IL-8 and TNF-α levels were also significantly lower than those in the PN group and EN group (27.0 pg/mL ± 7.9 pg/mL vs 47.6 pg/mL ± 8.4 pg/mL vs 31.0 pg/mL ± 8.0 pg/mL; 43.5 pg/mL ± 22.7 pg/mL vs 132.5 pg/mL ± 32.6 pg/mL vs 67.5 pg/mL ± 21.4 pg/mL; F = 8.375, 7.278; P = 0.017, 0.012). Plasma CRP and LDH levels were significantly lower in the P + EN group after treatment than in the PN group and EN group (39.4 mg/L ± 19.7 mg/L vs 102.5 mg/L ± 41.9 mg/L vs 68.3 mg/L ± 32.9 mg/L; 20.3 U/L ± 12.3 U/L vs 79.3 U/L ± 34.4 U/L vs 35.3 U/L ± 10.4 U/L; F = 8.353, 10.354; P = 0.032, 0.013). Gastrointestinal function scores in the PN group, EN group and P + EN group on 14 d were significantly decreased, and the decrease was more significant in the P + EN group than in the PN group and EN group (0.25 ± 0.02 vs 0.71 ± 0.08 vs 0.40 ± 0.04; F = 12.456; P = 0.000). The mortality and incidence of complications were significantly lower and duration of hospitalization was significantly shorter in the combination group than in the EN group (χ² = 4.428, 28.986; P = 0.019, 0.000).

CONCLUSION: Early application of EN combined with Bifico can reduce the levels of enzymes and mediators of inflammation, pancreatic secretion, complications, hospitalization time, and mortality in SAP patients.

Probiotic actions on diseases: implications for therapeutic treatments

The ecology of gut microflora, which colonizes all body surfaces, has long coevolved with its hosts in a complicated fashion. Health benefits conferred by gut microflora include defense against invading pathogens, improvement of nutritional bioavailability, and development of the regional and systemic immune systems. The past decade has witnessed growing interest in the fact that the gut microflora affects the host's energy homeostasis by means of various mechanisms, including supplying nourishment from indigestible compounds, producing small biomolecules responsible for lipid profiles, and participating in the absorption, distribution, metabolism and excretion of nutrition. Much in vitro and in vivo research has indicated that aberrant gut microflora plays an important role in the pathogenesis of a wide spectrum of diseases. This is accomplished by a shift in focus, from laying an emphasis on pharmacotherapy to placing more effort on gut microflora normalization. The objectives of this review include illustrating trends in the clinical application of probiotics on diseases, as well as discussing current methodology limitations on probiotic selection. Furthermore, it is expected to shed light on the nature of probiotics, with the aim of giving greater insight into the implications for clinical use of probiotics in the treatment of diseases.

Nutritional and Physical Activity Interventions to Improve Immunity

Physical activity and nutrition are important in a healthy lifestyle with potential benefits to immunity often overlooked. Infection of the upper respiratory tract, and the associated symptoms, are the most frequent presentations to general practitioners and may have significant economic and social impact. In this review, we consider the role of physical activity and nutrition in improving immunity. Evidence suggests that regular moderate activity is particularly beneficial for immune enhancement and reducing the risk of infection. We also discuss some nutritional strategies. Unfortunately, the evidence for many is weak. Avoiding nutritional deficiencies seems the most pragmatic recommendation. This can be achieved with a balanced diet. Including a variety of fruits and vegetables may help ensure adequate intake of essential nutrients with little risk of excess intake of any single nutrient. Supplementation with individual nutrients is generally not recommended. Multinutrients may be beneficial for those with a preexisting deficiency but not if normal dietary intake is sufficient. Further benefit may be gained from some supplements including probiotics, bovine colostrum, and some plant-derived products (Echinacea, black elderberry, and some polyphenols) but only in specific situations/contexts. Individuals should consider their personal needs, use caution, and avoid the indiscriminate use of supplements.

Commercially available probiotic drinks containing Lactobacillus casei DN-114001 reduce antibiotic-associated diarrhea

AIM: To investigate the effect of Lactobacillus-containing commercially available probiotic formulations in Germany during antibiotic treatment with an analysis of cost-efficiency.

METHODS: In an observational study, we analyzed the frequency of bowel movements from 258 patients with infections in a primary care hospital in western Germany; 107 of the patients were offered a probiotic drink containing at least 10 billion cultures of Lactobacillus casei DN 114001 b.i.d. The economic analysis was based on the costs of patient isolation vs preventive intake of probiotics. In a second pilot study, two commercially available probiotic drinks with different Lactobacillus casei strains were directly compared in 60 patients in a randomized controlled fashion.

RESULTS: In the first study, the incidence of antibiotic-associated diarrhea (AAD) was significantly reduced in the intervention group (6.5% vs 28.4%), and the duration of AAD in days was significantly shorter (1.7 ± 1.1 vs 3.1 ± 2.1). Higher age and creatinine and lower albumin were identified as risk factors for AAD. Ampicillin was the antibiotic with the highest rate of AAD (50%) and with the greatest AAD reduction in the probiotic group (4.2%, relative risk reduction 92%). The economic analysis showed a cost advantage of nearly 60000 €/year in a department of this size. The second study confirmed the preventive effect of the drink with Lactobacillus casei DN114001; however, there were no advantages found for the other tested probiotic drink containing Lactobacillus casei Shirota.

CONCLUSION: In contrast to a drink containing Lactobacillus casei Shirota, a commercially available probiotic drink containing Lactobacillus casei DN 114001 cost-efficiently reduces the prevalence of AAD during antibiotic treatment.

Intestinal microbiota, probiotics and prebiotics in inflammatory bowel disease

It has been presumed that aberrant immune response to intestinal microorganisms in genetically predisposed individuals may play a major role in the pathogenesis of the inflammatory bowel disease, and there is a good deal of evidence supporting this hypothesis. Commensal enteric bacteria probably play a central role in pathogenesis, providing continuous antigenic stimulation that causes chronic intestinal injury. A strong biologic rationale supports the use of probiotics and prebiotics for inflammatory bowel disease therapy. Many probiotic strains exhibit anti-inflammatory properties through their effects on different immune cells, pro-inflammatory cytokine secretion depression, and the induction of anti-inflammatory cytokines. There is very strong evidence supporting the use of multispecies probiotic VSL#3 for the prevention or recurrence of postoperative pouchitis in patients. For treatment of active ulcerative colitis, as well as for maintenance therapy, the clinical evidence of efficacy is strongest for VSL#3 and Escherichia coli Nissle 1917. Moreover, some prebiotics, such as germinated barley foodstuff, Psyllium or oligofructose-enriched inulin, might provide some benefit in patients with active ulcerative colitis or ulcerative colitis in remission. The results of clinical trials in the treatment of active Crohn’s disease or the maintenance of its remission with probiotics and prebiotics are disappointing and do not support their use in this disease. The only exception is weak evidence of advantageous use of Saccharomyces boulardii concomitantly with medical therapy in maintenance treatment.

Probiotics in treatment of severe acute pancreatitis

Severe acute pancreatitis (SAP) is a life-threatening condition characterized by high mortality, with infection and bacteremia being major causes of death. Prophylactic antibiotic administration failed to show any favorable effect on the incidence of infectious complications in SAP patients. Consequently, microorganism intervention is recommend by World Health Organization (WHO). Probiotics improve the prognosis of SAP patients by promoting gastrointestinal peristalsis, modulating the content of gut microbiota, maintaining the integrity of the gut barrier, modulating the immune response by the gut-associated immune system and reducing the damage to the pancreas, lung and liver. It has been demonstrated that probiotics in combination with immunonutrition could improve the prognosis of SAP patients. However, the use of probiotics in SAP remains controversial currently.

Obesity as a consequence of gut bacteria and diet interactions

Obesity is a major public health concern, caused by a combination of increased consumption of energy-dense foods and reduced physical activity, with contributions from host genetics, environment, and adipose tissue inflammation. In recent years, the gut microbiome has also been found to be implicated and augmented research in mice and humans have attributed to it both the manifestation and/or exacerbation of this major epidemic and vice versa. At the experimental level, analysis of fecal samples revealed a potential link between obesity and alterations in the gut flora (drop in Bacteroidetes and increase in Firmicutes), the specific gut microbiome being associated with the obese phenotype. Conventionally raised mice were found to have over 40% more total body fat compared with those raised under germ-free conditions, while conventionalization of germ-free mice resulted in a significant increase in total body fat. Similarly, the sparse data in humans supports the fact that fat storage is favoured by the presence of the gut microbiota, through a multifaceted mechanism. Efforts to identify new therapeutic strategies to modulate gut microbiota would be of high priority for public health, and to date, probiotics and/or prebiotics seem to be the most effective tools.

Nutraceuticals for older people: facts, fictions and gaps in knowledge

In the last decades nutraceuticals have entered the health market as an easy and attractive means of preventing diseases. These products are of interest for an increasingly health-concerned society and may be especially relevant for preventing or delaying a number of age-related diseases, i.e. arthritis, cancer, metabolic and cardiovascular diseases, osteoporosis, cataracts, brain disorders, etc. Nutraceuticals are marketed in a variety of forms, composition and potential applications which have made their definition ambiguous and their use uncontrolled and poorly funded. Although epidemiological, animal and in vitro studies have given evidence of the potential benefits of some of these nutraceuticals or of their components, definitive proof of their effects in appropriate human clinical trials is still lacking in most cases, more critically among people above 65 years of age. We cover the well-established nutraceuticals (polyvitamins, omega-3 fatty acids, etc.) and will focus on many other 'novel' commercial nutraceuticals where the scientific evidence is more limited (food extracts, polyphenols, carotenoids, etc.). Solid scientific evidence has been reported only for a few nutraceuticals, which have some health claims approved by the European Food Safety Authority (EFSA). Further well-designed trials are needed to improve the current knowledge on the health benefits of nutraceuticals in the elderly. Overall, there are some facts, a lot of fiction and many gaps in the knowledge of nutraceutical benefits.