Current and potential uses of probiotics

Abd El-Maksoud A, M. Ambrósio F. de Gouveia G. Recent Development in Antioxidant of Milk and Its Products

Free radicals are produced in humans through natural metabolism or the external environment, such as diet. These free radicals are neutralized by the antioxidant system, whereas enzymes, for example, catalase, superoxide dismutase, and glutathione peroxidase, play an important role in preventing excessive free radicals. Food antioxidants give a good hand in enhancing the human antioxidant system; high consumption of a diet rich in natural antioxidants protects against the risk of diseases such as cardiovascular, cancer, diabetes, and obesity. Milk and its products are popular for a wide range of consumers. Milk contains casein, whey protein, lactoferrin, milk lipid and phospholipids, vitamins, and microelements, for example, selenium (Se), which have antioxidant properties. Furthermore, probiotication of milk either sweet or fermented could enhance the antioxidant capacity of milk. This chapter focuses on presenting recent review data on milk components with antioxidant activity and their health benefits, probiotics as antioxidant agents, and methods for enhancing the antioxidant capacity of dairy products. The key aim of this chapter is to focus on major strategies for enhancing the antioxidant capacity of milk and its products.

The potential of probiotics in the amelioration of hyperuricemia

Hyperuricemia is a common disease caused by metabolic disorders or the excessive intake of high-purine foods. Persistent hyperuricemia in extreme cases induces gout, and asymptomatic hyperuricemia is probably linked to other metabolic diseases, such as hypertension. The typical damage caused by asymptomatic hyperuricemia includes inflammation, oxidative stress and gut dysbiosis. Probiotics have broad potential applications as food additives, not as drug therapies, in the amelioration of hyperuricemia. In this review, we describe novel methods for potential hyperuricemia amelioration with probiotics. The pathways through which probiotics may ameliorate hyperuricemia are discussed, including the decrease in uric acid production through purine assimilation and XOD (xanthine oxidase) inhibition as well as enhanced excretion of uric acid production by promoting ABCG2 (ATP binding cassette subfamily G member 2) activity, respectively. Three possible probiotic-related therapeutic pathways for alleviating the syndrome of hyperuricemia are also summarized. The first mechanism is to alleviate the oxidation and inflammation induced by hyperuricemia through the inhibition of NLRP3 inflammasome, the second is to restore damaged intestinal epithelium barriers and prevent gut microbiota dysbiosis, and the third is to enhance the innate immune system by increasing the secretion of immunoglobulin A (sIgA) to resist the stimulus by hyperuricemia. We propose that future research should focus on superior strain resource isolation and insight into the cause-effect mechanisms of probiotics for hyperuricemia amelioration. The safety and effects of the application of probiotics in clinical use also need verification.

Probiotics for glycemic control in patients with type 2 diabetes mellitus: protocol for a systematic review

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a major public health problem worldwide. It is characterized by the increased concentration of glucose in the blood and leads to damage of the body system, especially blood vessels and nerves. Lifestyle modification is often combined with anti-diabetic therapy as the standard of care for T2DM to maintain the proper blood glucose and to prevent long-term diabetic complications. The role of probiotics in improving glycemic control has been investigated in several randomized controlled trials (RCTs). Previous systematic reviews and meta-analyses, including different sets of trials have concluded an overall beneficial effect of probiotics in patients with T2DM. At least two RCTs with a longer treatment duration have been published since the publication of existing reviews.

METHODS

We will conduct a systematic review of RCTs that evaluated the effectiveness and safety of probiotics for glycemic control in T2DM patients. Primary outcomes are fasting blood glucose and glycosylated hemoglobin (A1c). Secondary outcomes are plasma insulin, blood lipid profile, adverse events, and cost associated with the intervention and hospital visits. We will search PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, and trial registries. Two reviewers will independently screen titles and abstracts, review full texts, extract information, and assess the risk of bias. We will summarize the results both qualitatively and statistically. We will use random-effects model for meta-analysis.

DISCUSSION

This systematic review aims to examine whether probiotics are effective and safe for glycemic control in T2DM patients. Evidence generated from this review will inform clinical and public health practice and future research.

SYSTEMATIC REVIEW REGISTRATION

CRD42019121682.

Antioxidant Properties of Probiotic Bacteria

Oxidative stress defines a condition in which the prooxidant-antioxidant balance in the cell is disturbed, resulting in DNA hydroxylation, protein denaturation, lipid peroxidation, and apoptosis, ultimately compromising cells' viability. Probiotics have been known for many beneficial health effects, and the consumption of probiotics alone or in food shows that strain-specific probiotics can present antioxidant activity and reduce damages caused by oxidation. However, the oxidation-resistant ability of probiotics, especially the underling mechanisms, is not properly understood. In this view, there is interest to figure out the antioxidant property of probiotics and summarize the mode of action of probiotic bacteria in antioxidation. Therefore, in the present paper, the antioxidant mechanisms of probiotics have been reviewed in terms of their ability to improve the antioxidant system and their ability to decrease radical generation. Since in recent years, oxidative stress has been associated with an altered gut microbiota, the effects of probiotics on intestinal flora composition are also elaborated.

Phylogenetic identification of bacterial MazF toxin protein motifs among probiotic strains and foodborne pathogens and potential implications of engineered probiotic intervention in food

BACKGROUND

Toxin-antitoxin (TA) systems are commonly found in bacteria and Archaea, and it is the most common mechanism involved in bacterial programmed cell death or apoptosis. Recently, MazF, the toxin component of the toxin-antitoxin module, has been categorized as an endoribonuclease, or it may have a function similar to that of a RNA interference enzyme.

RESULTS

In this paper, with comparative data and phylogenetic analyses, we are able to identify several potential MazF-conserved motifs in limited subsets of foodborne pathogens and probiotic strains and further provide a molecular basis for the development of engineered/synthetic probiotic strains for the mitigation of foodborne illnesses. Our findings also show that some probiotic strains, as fit as many bacterial foodborne pathogens, can be genetically categorized into three major groups based on phylogenetic analysis of MazF. In each group, potential functional motifs are conserved in phylogenetically distant species, including foodborne pathogens and probiotic strains.

CONCLUSION

These data provide important knowledge for the identification and computational prediction of functional motifs related to programmed cell death. Potential implications of these findings include the use of engineered probiotic interventions in food or use of a natural probiotic cocktail with specificity for controlling targeted foodborne pathogens.

A trial of adding Lactobacillus johnsonii EM1 to levocetirizine for treatment of perennial allergic rhinitis in children aged 7-12 years

BACKGROUND

Supplementary consumption of probiotics may temporarily alter the intestinal microflora of infants and children, thereby preventing and treating allergic disorders.

OBJECTIVE

To compare the clinical efficacy of levocetirizine with that of levocetirizine plus Lactobacillus johnsonii EM1 (Lj EM1) for treating perennial allergic rhinitis (PAR) in children.

METHODS

Sixty-three children aged 7-12 years fulfilled the entry criteria for the study and had moderate to severe PAR of at least 1 year's duration. The treatment followed a randomized, open-label crossover design: all subjects were randomized to 2 crossover treatment regimens of levocetirizine with Lj EM1 (group 1) or levocetirizine alone (group 2) for 12 weeks; subsequently, treatments were reversed for a further 12 weeks. The effects of the 2 regimens were compared using the Pediatric Rhinoconjunctivitis Quality of Life Questionnaire (PRQLQ) and the total symptom score (TSS) from diary cards. The parameters evaluated were nasal peak expiratory flow rate (nPEFR), FVC, FEV1, serum immunoglobulin E (IgE), mite-specific IgE, eosinophilic cationic protein (ECP), resistin, blood eosinophils, eosinophil percentage in nasal smears, IL-4, IL-10, interferon-γ (IFN-γ), and transforming growth factor-β (TGF-β).

RESULTS

After the first 12 weeks of treatment, TSS in both groups had improved progressively compared with that in the run-in period. Both groups had improved TSS at weeks 4, 8, and 12 (P<0.05), and group 1 was more efficacious than group 2 at week 4 (P=0.014), week 8 (P=0.011), and week 12 (P<0.009). During the second 12-week period, group 2 showed continual and progressive improvement, while group 1 did not. The PRQLQ scores were significantly decreased in both groups (P<0.05), but there was no statistically significant difference between the 2 groups (P=0.446). The eosinophil percentage in nasal smears decreased in both groups compared with that in the run-in period, and significant differences were detected in groups 2 and 1at 16 and 24 weeks of treatment, respectively (P<0.05). Both groups showed significant improvement in nPEFR at weeks 4, 8, 12, 16, and 24 (P<0.01), and the treatment for group 1 appeared to be more efficacious than that for group 2 at weeks 12, 16, and 20 (P<0.05). FVC and FEV1 were improved in both groups at weeks 8 through 24 (P<0.05), but there was no significant difference between the 2 groups. In cytokine measurements, IFN-γ and IL-10 increased significantly and IL-4 decreased significantly in both groups, while elevation of TGF-β was seen only in group 1 at 12 weeks (P<0.001). However, the difference in TGF-β disappeared after 24 weeks treatment. There was no difference in serum resistin levels. No serious adverse events were recorded in either treatment group.

CONCLUSION

The 24-week, 2-phase, crossover treatment program showed that levocetirizine plus Lj EM1 was more effective for PAR than levocetirizine and that this difference persisted for at least 3 months after discontinuation of Lj EM1.

Oral administration of Lactobacillus salivarius inhibits the allergic airway response in mice

Asthma is recognized throughout the world as a chronic airway inflammatory disease. In this study, we investigated the effect of probiotics in response to antigen challenge in an ovalbumin (OVA)-sensitized asthma model in BALB/c mice. Lactobacillus salivarius PM-A0006 was orally administered to mice before antigen challenge. After antigen challenge, serum OVA-specific antibody levels, airway responsiveness to methacholine, influx of inflammatory cells to the lung, and cytokine levels in bronchoalveolar lavage (BAL) fluid and splenocytes were assessed. Oral treatment with live L. salivarius PM-A0006 significantly attenuated the influx of eosinophils to the airway lumen and reduced the levels of serum OVA-specific IgE and eotaxin in BAL fluid of antigen-challenged animals. Furthermore, L. salivarius PM-A0006 also decreased allergen-induced airway hyperresponsiveness and elevated the levels of IFN-gamma. These results showed that oral treatment with L. salivarius PM-A0006 could have therapeutic potential in the treatment of allergic airway disease.

Bacteriophage Administration Reduces the Concentration of Listeria monocytogenes in the Gastrointestinal Tract and Its Translocation to Spleen and Liver in Experimentally Infected Mice

To investigate the efficacy of phage supplementation in reducing pathogen numbers, mice were treated via oral gavage with a Listeria monocytogenes phage preparation (designated ListShield) before being orally infected with L. monocytogenes. The concentrations of L. monocytogenes in the liver, spleen, and intestines were significantly lower (P < .05) in the phage-treated than in the control mice. Phage and antibiotic treatments were similarly effective in reducing the levels of L. monocytogenes in the internal organs of the infected mice. However, the significant weight loss detected in the control and antibiotic-treated groups was not observed in the infected, ListShield-treated mice. Long-term (90 days), biweekly treatment of uninfected mice with ListShield did not elicit detectable changes in the microbiota of their large intestines or deleterious changes in their health. Our data support the potential feasibility of using bacteriophages to control proliferation of L. monocytogenes in mice without affecting commensal microbiota composition.

Probiotics

PURPOSE

The pharmacology, uses, dosages, safety, drug interactions, and contraindications of probiotics are reviewed.

SUMMARY

Probiotics are live nonpathogenic microorganisms administered to improve microbial balance, particularly in the gastrointestinal tract. They consist of Saccharomyces boulardii yeast or lactic acid bacteria, such as Lactobacillus and Bifidobacterium species, and are regulated as dietary supplements and foods. Probiotics exert their beneficial effects through various mechanisms, including lowering intestinal pH, decreasing colonization and invasion by pathogenic organisms, and modifying the host immune response. Probiotic benefits associated with one species or strain do not necessarily hold true for others. The strongest evidence for the clinical effectiveness of probiotics has been in the treatment of acute diarrhea, most commonly due to rotavirus, and pouchitis. More research is needed to clarify the role of probiotics for preventing antibiotic-associated diarrhea, Clostridium difficile infection, travelers' diarrhea, irritable bowel syndrome, ulcerative colitis, Crohn's disease, and vulvovaginal candidiasis. There is no consensus about the minimum number of microorganisms that must be ingested to obtain a beneficial effect; however, a probiotic should typically contain several billion microorganisms to increase the chance that adequate gut colonization will occur. Probiotics are generally considered safe and well tolerated, with bloating and flatulence occurring most frequently. They should be used cautiously in patients who are critically ill or severely immunocompromised or those with central venous catheters since systemic infections may rarely occur. Bacteria-derived probiotics should be separated from antibiotics by at least two hours.

CONCLUSION

Probiotics have demonstrated efficacy in preventing and treating various medical conditions, particularly those involving the gastrointestinal tract. Data supporting their role in other conditions are often conflicting.

Probiotics and Prebiotics: Why Are They “Bugging” Us in the Pharmacy?

OBJECTIVES Specific organisms can be added to foods to target an effect (probiotics) or non-digestible carbohydrates can be used to foster the development of a favorable flora in the intestinal tract (prebiotics). The significance of pro- and prebiotics have been studied extensively, providing many current and theoretical treatment options. The objective of this paper is to provide a brief overview of commercial products available for the practicing clinician.

METHODS The literature was evaluated for the most commonly used and studied pre- and probiotics available. In addition, information regarding each of the products was obtained from the manufacturer.

RESULTS We found that all products are not formulated the same and the content of live organisms can differ. Currently available products are relatively safe but caution should be used for any patients that may have allergies to inactive ingredients in the product or are immunocompromised.

CONCLUSIONS Many probiotics and prebiotics are commercially available to aid in promoting healthy bowel flora to resist disease. This reference can be a helpful tool for the pharmacist when answering questions or making recommendations to a patient.

Long-term colonization of a Lactobacillus plantarum synbiotic preparation in the neonatal gut

BACKGROUND

Probiotic, prebiotic, and synbiotic (a combination of pro- and prebiotic) supplements increasingly are being used to prevent and treat a variety of health conditions. Although colonization is considered a key element in the success of such treatments, few clinical studies have addressed colonizing ability. Studies are even more limited in neonates and infants, who may benefit most from such treatment. The present study was conducted to determine the colonizing ability, tolerance, and impact on the stool flora of 7 days of administration of a synbiotic supplement to a neonatal cohort, in preparation for a larger hospital-based trial.

PATIENTS AND METHODS

In this randomized, double-masked, controlled trial, healthy inborn newborns >35 weeks of gestational age and >1800 g birth weight were randomized between 1 and 3 days after birth to receive an oral synbiotic preparation (Lactobacillus plantarum and fructooligosaccharides) or a dextrose saline placebo. Two babies were treated with the synbiotic preparation for every 1 baby treated with the placebo. Duration of therapy was 7 days. Comprehensive stool cultures were done at baseline and on days 3, 7, 14, 21, and 28.

RESULTS

Nineteen infants received the active study supplement and 12 infants received the placebo for 7 days. L plantarum was cultured from the stools of 84% of the treated infants after 3 days of treatment, and from 95% of infants on day 28 after birth. Of the infants, 100%, 94%, 88%, 56%, and 32% remained colonized at months 2, 3, 4, 5, and 6, respectively. In both groups, the total mean number of species and the mean log colony counts increased over time. The number of bacterial species was significantly higher on days 21 and 28 in the synbiotic preparation group compared with placebo (P = 0.002 and 0.03, respectively). There was a linear increase in the mean log gram-negative colony counts in the placebo group during the 4-week period that was significantly higher than that in the Lactobacillus group on days 14, 21, and 28 (P < 0.001 for each). In contrast, the supplement group had significantly higher gram-positive colony counts on days 14 (P = 0.002) and 28 (P = 0.04). Only 1 infant in the placebo group was colonized with L fermentum during the first 28 days of life. No difference was found in the percent increase in weight between baseline and day 7, but on day 28 and months 2, 3, and 6, the percent increase from baseline was higher in the probiotic-treated group (P </= 0.05). The supplement was tolerated well.

CONCLUSIONS

The synbiotic preparation colonized quickly after 3 days of administration and the infants stayed colonized for several months after therapy was stopped. There was an increase in bacterial diversity and gram-positive organisms and a reduction of gram-negative bacterial load in the treatment group. Because a combination preparation was used, it is difficult to specifically attribute the colonization to either the probiotic or prebiotic component in this study. Larger efficacy trials are warranted to examine the mechanism of action and precise effects of these supplements.

Probiotic-induced suppression of allergic sensitization and airway inflammation is associated with an increase of T regulatory-dependent mechanisms in a murine model of asthma

BACKGROUND

Microbial intestinal colonization in early in life is regarded to play a major role for the maturation of the immune system. Application of non-pathogenic probiotic bacteria during early infancy might protect from allergic disorders but underlying mechanisms have not been analysed so far.

OBJECTIVE

The aim of the current study was to investigate the immune effects of oral application of probiotic bacteria on allergen-induced sensitization and development of airway inflammation and airway hyper-reactivity, cardinal features of bronchial asthma.

METHODS

Newborn Balb/c mice received orally 10(9) CFU every second day either Lactobacillus rhamnosus GG or Bifidobacterium lactis (Bb-12) starting from birth for consecutive 8 weeks, during systemic sensitization (six intraperitoneal injections, days 29-40) and airway challenge (days 54-56) with ovalbumin.

RESULTS

The administration of either Bb-12 or LGG suppressed all aspects of the asthmatic phenotype: airway reactivity, antigen-specific immunoglobulin E production and pulmonary eosinophilia (mean: 137 vs. 17 and 13 cellsx10(3)/mL, respectively). Antigen-specific recall proliferation by spleen cells and T-helper type 2 cytokine production (IL-4, IL-5 and IL-10) by mesenteric lymph node cells also showed significant reduction, while TGF production remained unchanged. Oral LGG administration particularly suppressed allergen-induced proliferative responses and was associated with an increase in numbers of TGF-beta-secreting CD4+/CD3+ T cells in mesenteric lymph nodes (6.5, 16.7%) as well as nearly 2-fold up-regulation of Foxp3-expressing cells in peribronchial lymph nodes.

CONCLUSIONS

Neonatal application of probiotic bacteria inhibits subsequent allergic sensitization and airway disease in a murine model of asthma by induction of T regulatory cells associated with increased TGF-beta production.

Toll-like receptors—novel targets in allergic airway disease (probiotics, friends and relatives)

Experimental and epidemiological studies enabled to hypothesize that stimulation of the immune system by selected microbial products may prevent or treat allergic diseases. According to recent advances in molecular immunology, this stimulation acts via group of conserved receptors present on antigen presenting cells, known as toll-like receptors (TLRs). These receptors play an essential role in antigen presentation and latter development of immune response into pro-allergic (Th2), cellular (Th1) or regulatory (Tr1) responses. Since toll-like receptors govern decisive points in immune regulation, an extensive research focuses on agents interfering with their immunomodulatory activities. In this report, we review information on the potential use of microbial products in allergy prevention and therapy, which are believed to target toll-like receptor network. Current toll-like receptor-based approaches, as well as potential use of lipopolysaccharide (and derivates), oligonucleotides, mycobacteria, bacterial extracts, and probiotics are discussed herein.