Clinical trial on the efficacy of a new symbiotic formulation, Flortec, in patients with acute diarrhea: a multicenter, randomized study in primary care

Future Modulation of Gut Microbiota: From Eubiotics to FMT, Engineered Bacteria, and Phage Therapy

The human gut is inhabited by a multitude of bacteria, yeasts, and viruses. A dynamic balance among these microorganisms is associated with the well-being of the human being, and a large body of evidence supports a role of dysbiosis in the pathogenesis of several diseases. Given the importance of the gut microbiota in the preservation of human health, probiotics, prebiotics, synbiotics, and postbiotics have been classically used as strategies to modulate the gut microbiota and achieve beneficial effects for the host. Nonetheless, several molecules not typically included in these categories have demonstrated a role in restoring the equilibrium among the components of the gut microbiota. Among these, rifaximin, as well as other antimicrobial drugs, such as triclosan, or natural compounds (including evodiamine and polyphenols) have common pleiotropic characteristics. On one hand, they suppress the growth of dangerous bacteria while promoting beneficial bacteria in the gut microbiota. On the other hand, they contribute to the regulation of the immune response in the case of dysbiosis by directly influencing the immune system and epithelial cells or by inducing the gut bacteria to produce immune-modulatory compounds, such as short-chain fatty acids. Fecal microbiota transplantation (FMT) has also been investigated as a procedure to restore the equilibrium of the gut microbiota and has shown benefits in many diseases, including inflammatory bowel disease, chronic liver disorders, and extraintestinal autoimmune conditions. One of the most significant limits of the current techniques used to modulate the gut microbiota is the lack of tools that can precisely modulate specific members of complex microbial communities. Novel approaches, including the use of engineered probiotic bacteria or bacteriophage-based therapy, have recently appeared as promising strategies to provide targeted and tailored therapeutic modulation of the gut microbiota, but their role in clinical practice has yet to be clarified. The aim of this review is to discuss the most recently introduced innovations in the field of therapeutic microbiome modulation.

Putative Probiotic Strains Isolated from Kefir Improve Gastrointestinal Health Parameters in Adults: a Randomized, Single-Blind, Placebo-Controlled Study

The dairy products remain as the largest reservoir for isolation of probiotic microorganisms. While probiotics have been immensely reported to exert various health benefits, it is also a common notion that these health potentials are strain and host dependent, leading to the need of more human evidence based on specific strains, health targets, and populations. This randomized, single-blind, and placebo-controlled human study aimed to evaluate the potential benefits of putative probiotic strains isolated from kefir on gastrointestinal parameters in fifty-six healthy adults. The consumption of AB-kefir (Bifidobacterium longum, Lactobacillus acidophilus, L. fermentum, L. helveticus, L. paracasei, L. rhamnosus, and Streptococcus thermophiles; total 10 log CFU/sachet) daily for 3 week reduced symptoms of abdominal pain, bloating (P = 0.014), and appetite (P = 0.041) in male subjects as compared to the control. Gut microbiota distribution profiles were shifted upon consumption of AB-kefir compared to baseline, where the abundance of bifidobacteria was increased in male subjects and maintained upon cessation of AB-kefir consumption. The consumption of AB-kefir also increased gastrointestinal abundance of total anaerobes (P = 0.038) and total bacterial (P = 0.049) in female subjects compared to the control after 3 weeks. Our results indicated that AB-kefir could potentially be developed as a natural strategy to improve gastrointestinal functions in adults.

Practical Recommendations of Scientific Society for the Study of Human Microbiome and the Russian Gastroenterological Association on Use of Probiotics, Prebiotics, Synbiotics and Functional Foods in Treatment and Prevention of Gastroenterological Diseases in Children and Adults

Aim. The practical guidelines are intended for primary care physicians, general practitioners, paediatricians, gastroenterologists and general internists to advance the treatment and prevention of gastroenterological diseases in adults and children in therapies with probiotics, prebiotics, synbiotics and their enriched functional foods.

Key points. Probiotics are live microorganisms that sustain health of the host when supplied in adequate amounts. Prebiotics include human-indigestible but accessible to gut microbiota substances expediting specific changes in the composition and/or activity of gastrointestinal microbiota that favour the host health. The mechanism of probiotic action comprises the quorum resistance maintenance, nutrient substrate metabolism and end metabolite recycling, macroorganism-sustaining substrate production, as well as the mediation of local and adaptive immune responses.

The Russian Federation regulates market differently for biologically active food additives (BAFA), medicinal products (drugs) and functional food products (FFP). We overview the probiotic strains regulated in Russia as BAFAs, drugs and FFPs and provide recommendations on the use of these strains in treatment and prevention of gastroenterological diseases in children and adults.

Conclusion. The clinical efficacy of probiotics, prebiotics, synbiotics and fortified functional foods depends on the prebiotic and strain properties and is verified in appropriate comparative clinical trials. Not all probiotics registered in Russia as BAFAs, drugs and FFPs have a strain identity, which provides no warranty of the clinical effect expected. The FFP legislation demands improved regulation mechanisms and control for therapeutic efficacy.

Serological Biomarkers and Diversion Colitis: Changes after Stimulation with Probiotics

Diversion colitis is a non-specific inflammation of a defunctionalised segment of the colon after a temporary stoma has been performed. This inflammation is associated with an alteration of certain inflammatory serum markers. The aims of this study were, firstly, to evaluate the modification of inflammatory biomarkers after stimulation with probiotics prior to closure of the protective ileostomy. Secondly, to identify if a relationship could be established between the severity of diversion colitis and the alteration of inflammatory biomarkers in the blood. A prospective, randomized, double-blind, controlled study was conducted. Patients who underwent surgery for colorectal carcinoma with protective ileostomy between January 2017 and December 2018 were included, pending reconstructive surgery and with diversion colitis as diagnosis. The sample was randomly divided into a group stimulated with probiotics (SG) (n = 34) and a control group (CG) (n = 35). Histological and endoscopic changes were evaluated after stimulation, after restorative surgery and during the short-term follow-up after surgery, including the correlation with pro-inflammatory biomarkers in blood. As main findings, a significant decrease in C-reactive protein (CRP), Neutrophil/lymphocyte ratio (NLR ratio), and monocyte/lymphocyte ratio (LMR ratio) was observed in the SG versus the CG with a p < 0.001. A significant increase in transferrin values and in the platelet/lymphocyte ratio (PLR) was observed in the SG versus CG after stimulation with probiotics with a p < 0.001. A normalisation of CRP and transferrin levels was observed in the third month of follow-up after closure ileostomy, and NLR, LMR and PLR ratios were equal in both groups. Decreased modified Glasgow prognostic score was found in SG compared to CG after probiotic stimulation (p < 0.001). The endoscopic and histological severity of diversion colitis is associated with a greater alteration of blood inflammatory biomarkers. The stimulation with probiotics prior to reconstructive surgery promotes an early normalization of these parameters.

Practical Recommendations of Scientific Society for the Study of Human Microbiome and Russian Gastroenterological Association (RGA) for Probiotics in Treatment and Prevention of Gastroenterological Diseases in Adults

Aim. To provide practical recommendations on the use of probiotics for the treatment and prevention of gastroenterological diseases in adults.

General provisions. Probiotics are living microorganisms that benefit the health of the host when administered in adequate amounts. The main functions of probiotics include the support for colonisation resistance, the metabolism of food substrates and utilisation of end metabolites, the production of substrates necessary for the macro-organism, as well as the regulation of local and adaptive immune responses. Probiotics can be registered in the Russian Federation as biologically active food additives (BAFA) or as pharmaceutical products (drugs) in accordance with the microbiological standards and legislative requirements of the Russian Federation. The probiotics registered in the Russian Federation as BAFA for adults include bacteria of the Lactobacillus, Bifidobacterium, Enterococcus, Pediococcus, Lactococcus, Streptococcus, Bacillus, and Escherichia genera, and fungi of the Saccharomyces genus; probiotics registered as drugs — bacteria of Lactobid, Lactobacid, Escherichia and Enterococcus genera and fungi of the Saccharomyces genus. Some probiotics registered in the Russian Federation include probiotic strains that have proved to be effective for the prevention and treatment of antibiotic-associated diarrhea, the prevention of C. difficile-associated disease, the eradication of H. pylori infection, as well as for the treatment of irritable bowel syndrome and functional constipation.

Conclusions. The clinical efficacy of probiotics depends on the probiotic strains included in their composition and is confirmed by a comparative analysis of the results of appropriate clinical studies. Not all probiotics registered in the Russian Federation as BAFA or drugs contain bacterial or fungal strains; as a result, the expected clinical effect may not be achieved.

Probiotics, prebiotics and the gastrointestinal tract in health and disease

The microbiome located in the human gastrointestinal tract (GIT) comprises the largest community (diverse and dense) of bacteria, and in conjunction with a conducive internal milieu, promotes the development of regulated pro- and anti-inflammatory signals within the GIT that promotes immunological and metabolic tolerance. In addition, host-microbial interactions govern GIT inflammation and provide cues for upholding metabolic regulation in both the host and microbes. Failure to regulate inflammatory responses can increase the risk of developing inflammatory conditions in the GIT. Here, we review clinical studies regarding the efficacy of probiotics/prebiotics and the role they may have in restoring host metabolic homeostasis by rescuing the inflammatory response. The clinical studies reviewed included functional constipation, antibiotic-associated diarrhoea, Clostridium difficile diarrhoea, infectious diarrhoea/gastroenteritis, irritable bowel syndrome, inflammatory bowel diseases and necrotizing enterocolitis. We have demonstrated that there was an overall reduction in risk when probiotics were administered over placebo in the majority of GIT inflammatory conditions. The effect size of a cumulative reduction in relative risk for the GIT conditions/diseases investigated was 0.65 (0.61-0.70) (z = 13.3); p < 0.0001 that is an average reduction in risk of 35 % in favour of probiotics. We also progress a hypothesis that the GIT comprises numerous micro-axes (e.g. mucus secretion, Th1/Th2 balance) that are in operational homeostasis; hence probiotics and prebiotics may have a significant pharmacobiotic regulatory role in maintaining host GIT homeostasis in disease states partially through reactive oxygen species signalling.

The use of probiotic strains in caries prevention: a systematic review

This paper aims to provide a systematic review of the caries-prevention effect of probiotics in human. The hypothesis was that the administration of probiotic strains might play a role in caries lesion prevention and in the control of caries-related risk factors. The main relevant databases (Medline, Embase) were searched. Quality of the Randomized Clinical Trials (RCTs) was classified using the “Consolidated Standards of Reporting Trials” (CONSORT) checklist and the Impact Factor (IF) value of each journal was recorded. Sixty-six papers were identified, and 23 fulfilled the inclusion criteria. Only three studies had caries lesion development as outcome, all the others reported caries risk factors as interim evaluation. Using the CONSORT Score, the papers were coded as 4 excellent, 9 good and 10 poor. The mean IF value recorded was 1.438. Probiotics may play a role as antagonistic agent on mutans streptococci (MS), acidogenic/aciduric bacteria that contributes to the caries process. In two-thirds of the selected papers, probiotics have demonstrated the capacity to reduce MS counts in saliva and/or plaque in short-term. The effect of probiotics on the development of caries lesion seems encouraging, but to date, RCTs on this topic are insufficient to provide scientific clinical evidence.

High-fibre diet and Lactobacillus paracasei B21060 in symptomatic uncomplicated diverticular disease

AIM: To investigate in symptomatic uncomplicated diverticular disease the efficacy of symbiotics associated with a high-fibre diet on abdominal symptoms.

METHODS: This study was a multicentre, 6-mo randomized, controlled, parallel-group intervention with a preceding 4-wk washout period. Consecutive outpatients with symptomatic uncomplicated diverticular disease, aged 40-80 years, evaluated in 4 Gastroenterology Units, were enrolled. Symptomatic uncomplicated diverticular disease patients were randomized to two treatment arms A or B. Treatment A (n = 24 patients) received 1 symbiotic sachet Flortec^© (Lactobacillus paracasei B21060) once daily plus high-fibre diet for 6 mo. Treatment B (n = 21 patients) received high-fibre diet alone for 6 mo. The primary endpoint was regression of abdominal symptoms and change of symptom severity after 3 and 6 mo of treatment.

RESULTS: In group A, the proportion of patients with abdominal pain < 24 h decreased from 100% at baseline to 35% and 25% after 3 and 6 mo, respectively (P < 0.001). In group B the proportion of patients with this symptom decreased from 90.5% at baseline to 61.9% and 38.1% after 3 and 6 mo, respectively (P = 0.001). Symptom improvement became statistically significant at 3 and 6 mo in group A and B, respectively.

The proportion of patients with abdominal pain >24 h decreased from 60% to 20% then 5% after 3 and 6 mo, respectively in group A (P < 0.001) and from 33.3% to 9.5% at both 3 and 6 mo in group B (P = 0.03). In group A the proportion of patients with abdominal bloating significantly decreased from 95% to 60% after 3 mo, and remained stable (65%) at 6-mo follow-up (P = 0.005) while in group B, no significant changes in abdominal bloating was observed (P = 0.11). After 6 mo of treatment, the mean visual analogic scale (VAS) values of both short-lasting abdominal pain (VAS, mean ± SD, group A: 4.6 ± 2.1 vs 2.2 ± 0.8, P = 0.02; group B: 4.6 ± 2.9 vs 2.0 ± 1.9, P = 0.03) and abdominal bloating (VAS, mean ± SD, group A: 5.3 ± 2.2 vs 3.0 ± 1.7, P = 0.005; group B: 5.3 ± 3.2 vs 2.3 ± 1.9, P = 0.006) decreased in both groups, whilst the VAS values of prolonged abdominal pain decreased in the Flortec^© group, but remained unchanged in the high-fibre diet group (VAS, mean ± SD, group A: 6.5 ± 1.5 vs 4.5 ± 2.1, P = 0.052; group B: 4.5 ± 3.8 vs 5.5 ± 3.5).

CONCLUSION: A high-fibre diet is effective in relieving abdominal symptoms in symptomatic uncomplicated diverticular disease. This treatment may be implemented by combining the high-fibre diet with Flortec^©.

Randomised clinical trial: efficacy of a new synbiotic formulation containing Lactobacillus paracasei B21060 plus arabinogalactan and xilooligosaccharides in children with acute diarrhoea

BACKGROUND

Acute diarrhoea is a frequent problem in children with heavy economic burden for families and society.

AIM

To test the efficacy of a new synbiotic formulation containing Lactobacillus paracasei B21060, arabinogalactan and xilooligosaccharides in children with acute diarrhoea.

METHODS

Double-blind, randomised, placebo-controlled trial, including children (age 3-36 m) with acute diarrhoea who were allocated to placebo or synbiotic group. Major outcome was resolution rate of diarrhoea at 72 h. Total duration of diarrhoea, daily stool outputs, stool consistency, working days lost by parents, adjunctive medications, and hospitalisation were also assessed.

RESULTS

We enrolled 55 children in placebo group and 52 in synbiotic group. The two groups were similar for demographic and clinical characteristics. Resolution rate of diarrhoea at 72 h was significantly higher in synbiotic group (67%) compared to placebo group (40%, P = 0.005). Children in synbiotic group showed a significant reduction in the duration of diarrhoea (90.5 h, 78.1-102.9 vs. 109.8 h, 96.0-123.5, P = 0.040), daily stool outputs (3.3, 2.8-3.8 vs. 2.4, 1.9-2.8, P = 0.005) and stool consistency (1.3, 0.9-1.6 vs. 0.6, 0.4-0.9, P = 0.002) compared to placebo group (data expressed as mean, 95% CI). Rate of parents that missed at least one working day (41.8% vs. 15.4%, P = 0.003), rate of children that needed adjunctive medications (25.5% vs. 5.8%, P = 0.005) or hospitalisation (10.9% vs. 0%, P = 0.014) after the first 72 h of treatment, were reduced in synbiotic group.

CONCLUSION

The synbiotic formulation studied is effective in children with acute diarrhoea. Australian New Zealand Clinical Trials Registry (ACTRN12611000641998).