Probiotics and Prebiotics Orally Assumed as Disease Modifiers for Stable Mild Atopic Dermatitis: An Italian Real-Life, Multicenter, Retrospective, Observational Study.

The role of the skin-gut axis in atopic dermatitis (AD) remains a subject of debate, limiting non-pharmacological interventions such as probiotics and prebiotics. To improve understanding of their potential as a monotherapy for stable mild cases, we conducted a real-life, multicenter, retrospective observational study in Italy. We administered three selected bacteria (Bifidobacterium animalis subsp. lactis BS01, Lactiplantibacillus plantarum LP14, and Lacticaseibacillus rhamnosus LR05) orally to patients with mild atopic dermatitis without a placebo control group, following up for 12 weeks. Clinical assessments using the Scoring Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), and Three-Item Severity (TIS) score were conducted on 144 enrolled patients (average age: 25.1 ± 17.6 years). Notably, both pruritus and AD-related lesions (erythema, edema/papules, excoriation) exhibited significant clinical and statistical improvement (p < 0.001) after 12 weeks of exclusive probiotic and prebiotic use. These preliminary results suggest a potential link between the skin-gut microbiome and support the rationale for using specific probiotics and prebiotics in mild AD, even for maintenance, to reduce flares and dysbiosis.

Exploring the Effects of Probiotic Treatment on Urinary and Serum Metabolic Profiles in Healthy Individuals.

Probiotics are live microorganisms that confer health benefits when administered in adequate amounts. They are used to promote gut health and alleviate various disorders. Recently, there has been an increasing interest in the potential effects of probiotics on human physiology. In the presented study, the effects of probiotic treatment on the metabolic profiles of human urine and serum using a nuclear magnetic resonance (NMR)-based metabonomic approach were investigated. Twenty-one healthy volunteers were enrolled in the study, and they received two different dosages of probiotics for 8 weeks. During the study, urine and serum samples were collected from volunteers before and during probiotic supplementation. The results showed that probiotics had a significant impact on the urinary and serum metabolic profiles without altering their phenotypes. This study demonstrated the effects of probiotics in terms of variations of metabolite levels resulting also from the different probiotic posology. Overall, the results suggest that probiotic administration may affect both urine and serum metabolomes, although more research is needed to understand the mechanisms and clinical implications of these effects. NMR-based metabonomic analysis of biofluids is a powerful tool for monitoring host-gut microflora dynamic interaction as well as for assessing the individual response to probiotic treatment.

Cell-free Lactiplantibacillus plantarum OC01 supernatant suppresses IL-6-induced proliferation and invasion of human colorectal cancer cells: Effect on ß-Catenin degradation and induction of autophagy.

Background and aim: Gut microbiota is considered as a complex organ of human body. The interaction between the host and microbiota is dynamic and controlled by a huge number of factors, such as lifestyle, geography, pharmaceuticals, diet, and stress. The breakdown of this relationship could change microbiota composition favoring the onset of several diseases, including cancer. Metabolites released by microbiota bacterial strains have been reported to elicit protective effects on the mucosa that could contrast cancer development and progression. Here, we tested the ability of specific probiotic strain Lactiplantibacillus plantarum OC01-derived metabolites (NCIMB 30624) to contrast the malignant features of colorectal cancer (CRC) cells. Experimental procedure: The study was performed on two cell lines, HCT116 and HT29, cultured in 2D and 3D, and focused on the hallmarks of cell proliferation and migration. Results and conclusion: Probiotic metabolites reduced cell proliferation both in 2D and 3D-spheroid cultures, the latter model mimicking the growth in vivo. The bacterial metabolites also contrasted the pro-growth and pro-migratory activity of inteurleukin-6 (IL-6), an inflammatory cytokine abundantly found in the tumor microenvironment of CRC. These effects were associated with inhibition of the ERK and of the mTOR/p70S6k pathways and with the inhibition of the E-to N-Cadherin switch. In a parallel study, we found that sodium butyrate (a representative of the main probiotic metabolites) induced autophagy and ß-Catenin degradation, which is consistent with the growth inhibitory activity. The present data indicate that the metabolites of Lactiplantibacillus plantarum OC01 (NCIMB 30624) elicits anti-tumor effect and support its possible inclusion as adjuvant therapy of CRC for limiting cancer growth and progression.

Growth Conditions Influence Lactobacillus Cell-Free Supernatant Impact on Viability, Biofilm Formation, and Co-Aggregation of the Oral Periodontopathogens Fusobacterium nucleatum and Porphyromonas gingivalis.

Fusobacterium nucleatum and Porphyromonas gingivalis human periodontopathogens play a leading part in oral squamous cell carcinoma through cell proliferation, invasion, and persistent inflammation promotion and maintenance. To explore how the activity of Lactobacillus-derived cell-free supernatants (CFSs) can be influenced by growth medium components, CFSs were produced both in the standard MRS and the novel animal-derivative-free "Terreno Industriale Lattobacilli" (TIL) media, and in vitro screened for the containment of F. nucleatum and P. gingivalis both single and co-cultured and also for the interference on their co-aggregation. The viability assay demonstrated that the Limosilactobacillus reuteri LRE11 and Ligilactobacillus salivarius LS03 MRS-produced CFSs were significantly more effective against single and co-cultured pathogens. All the other CFSs significantly improved their efficacy when produced in TIL. Both MRS- and TIL-produced CFSs significantly inhibited the single and co-cultured pathogen biofilm formation. Only Levilactobacillus brevis LBR01 CFS in MRS specifically reduced F. nucleatum and P. gingivalis co-aggregation, while viable LBR01, LS03, and LRE11 in MRS significantly co-aggregated with the pathogens, but only LS03 cultivated in TIL improved this effect. This work paves the way to better consider environmental growth conditions when screening for probiotic and postbiotic efficacy as crucial to pathogen aggregation, adhesion to the host's niches, and exclusion.

Lactobacillus johnsonii LJO02 (DSM 33828) Cell-Free Supernatant and Vitamin D Improve Wound Healing and Reduce Interleukin-6 Production in Staphylococcus aureus-Infected Human Keratinocytes.

Methicillin-resistant biofilm-forming Staphylococcus spp. are found in about 25% of the overall cases of chronic wounds, which can undergo malignant degeneration and be associated with skin cancer. Although antimicrobial agents are clinically used to counteract pathogens and promote wound healing, they are increasingly ineffective against multi-drug resistant bacteria. Moreover, they can induce dysbiosis, which favors opportunistic pathogen infections and alters immune responses. Consequently, research on pathogen containment strategies is crucial. We aimed to evaluate the potential beneficial effect of Lactobacillus johnsonii LJO02 cell-free supernatant (CFS) and vitamin D, as single treatments or in combination, on cell viability, wound healing, and the pro-inflammatory interleukin-6 (IL-6) production of a Staphylococcus aureus-infected human immortalized keratinocyte cell line (HaCaT) in vitro model. The analysis showed that LJO02 CFS 20% v/v ratio and 100 nM vitamin D promoted infected cell viability and wound healing and significantly reduced IL-6 production. However, their effect was not synergic, since no significant difference between the single and combined treatments was observed. LJO02 CFS topic application and vitamin D supplementation could provide a valuable strategy for attenuating S. aureus-induced pathogenesis, promoting wound healing and opening new therapeutic strategies supporting the conventional approaches.

In Vitro Selection of Lactobacillus and Bifidobacterium Probiotic Strains for the Management of Oral Pathobiont Infections Associated to Systemic Diseases.

The human oral pathobionts Aggregatibacter actinomycetemcomitans, Streptococcus mitis and Streptococcus mutans, in dysbiosis-promoting conditions, lead to oral infections, which also represent a threat to human systemic health. This scenario may be worsened by antibiotic misuse, which favours multi-drug resistance, making the research on pathogen containment strategies more than crucial. Therefore, we aimed to in vitro select the most promising probiotic strains against oral pathogen growth, viability, biofilm formation, and co-aggregation capacity, employing both the viable probiotics and their cell-free supernatants (CFSs). Interestingly, we also assessed probiotic efficacy against the three-pathogen co-culture, mimicking an environment similar to that in vivo. Overall, the results showed that Lactobacillus CFSs performed better than the Bifidobacterium, highlighting Limosilactobacillus reuteri LRE11, Lacticaseibacillus rhamnosus LR04, Lacticaseibacillus casei LC04, and Limosilactobacillus fermentum LF26 as the most effective strains, opening the chance to deeper investigation of their action and CFS composition. Altogether, the methodologies presented in this study can be used for probiotic efficacy screenings, in order to better focus the research on a viable probiotic, or on its postbiotics, suitable in case of infections.

Assessment of shelf-life and metabolic viability of a multi-strain synbiotic using standard and innovative enumeration technologies.

The number of live bacterial cells is the most used parameter to assess the quality of finished probiotic products. Plate counting (PC) is the standard method in industry to enumerate cells. Application of PC implies critical aspects related to the selection of optimal nutrient media and growth conditions and underestimation of viable but not cultivable (VBNC) cells. Flow-cytometry (FC) is a culture-independent methodology having the potential to selectively enumerate live, damaged, and dead cells representing a powerful tool for in-depth monitoring of probiotic products. We monitored the shelf life of a clinical batch of a synbiotic composition PDS-08 targeting the pediatric population by means of PC and FC according to International Conference on Harmonization (ICH) pharma guidelines testing the Arrhenius model as predictive tool; PC enumeration revealed higher destruction rate than FC suggesting a faster reduction in cultivability than membrane integrity and thus a possible shift of the bacteria into a VBNC status. PDS-08 maintained acidification capability over time, when re-suspended in nutrient medium, even in samples tested sub-optimally for CFU detection (below 1 billion cells/dose). Due to similar kinetics described by the study of metabolic activity and membrane integrity, FC might be suggested as a valid tool for the study of functional stability of a probiotic product.

The Gut-Ex-Vivo System (GEVS) Is a Dynamic and Versatile Tool for the Study of DNBS-Induced IBD in BALB/C and C57BL/6 Mice, Highlighting the Protective Role of Probiotics.

BACKGROUND: IBD is a spectrum of pathologies characterized by dysregulated immune activation leading to uncontrolled response against the intestine, thus resulting in chronic gut inflammation and tissue damage. Due to its complexity, the molecular mechanisms responsible for disease onset and progression are still elusive, thus requiring intense research effort. In this context, the development of models replicating the etiopathology of IBD and allowing the testing of new potential therapies is critical. METHODS: Colon from C57BL/6 or BALB/c mice was cultivated in a Gut-Ex-Vivo System (GEVS), exposed for 5 h to DNBS 1.5 or 2.5 mg/mL, in presence or absence of two probiotic formulations (P1 = Bifidobacterium breve BR03 (DSM16604) and B632 (DSM24706); P2 = Lacticaseibacillus rhamnosus LR04 (DSM16605), Lactiplantibacillus plantarum LP14 (DSM33401) and Lacticaseibacillus paracasei LPC09), and the main hallmarks of IBD were evaluated. RESULTS: Gene expression analysis revealed the following DNBS-induced effects: (i) compromised tight junction organization, responsible for tissue permeability dysregulation; (ii) induction of ER stress, and (iii) tissue inflammation in colon of C57BL/6 mice. Moreover, the concomitant DNBS-induced apoptosis and ferroptosis pathways were evident in colon from both BALB/c and C57BL/6 mice. Finally, the co-administration of probiotics completely prevented the detrimental effects of DNBS. CONCLUSIONS: Overall, we have provided results demonstrating that GEVS is a consistent, reliable, and cost-effective system for modeling DNBS-induced IBD, useful for studying the onset and progression of human disease at the molecular level, while also reducing animal suffering. Moreover, we have confirmed the beneficial effect of probiotics administration in promoting the remission of IBD.

Randomized Double-Blind Crossover Study for Evaluating a Probiotic Mixture on Gastrointestinal and Behavioral Symptoms of Autistic Children.

Autism spectrum disorders (ASDs) represent a diagnostic challenge with a still partially uncertain etiology, in which genetic and environmental factors have now been assessed. Among the hypotheses underlying the involvement of biological and environmental factors, the gut-brain axis is of particular interest in autism spectrum disorders. Several studies have highlighted the related incidence of particular gastrointestinal symptoms (GISs) in children suffering from ASDs. Probiotics have shown success in treating several gastrointestinal dysbiotic disorders; therefore, it is plausible to investigate whether they can alleviate behavioral symptoms as well. On these bases, a randomized double-blind crossover study with a placebo was conducted, evaluating the effects of a mixture of probiotics in a group of 61 subjects aged between 24 months and 16 years old with a diagnosis of ASD. Behavioral evaluation was performed through the administration of a questionnaire including a Parenting Stress Index (PSI) test and the Vineland Adaptive Behavior Scale (VABS). The Psycho-Educational Profile and the Autism Spectrum Rating Scale (ASRS) were also evaluated. Microbial composition analyses of fecal samples of the two groups was also performed. The study showed significant improvements in GISs, communication skills, maladaptive behaviors, and perceived parental stress level after the administration of probiotics. Microbiome alpha diversity was comparable between treatment arms and no significant differences were found, although beta diversity results were significantly different in the treatment group between T0 and T1 time points. Streptococcus thermophilus, Bifidobacterium longum, Limosilactobacillus fermentum, and Ligilactobacillus salivarius species were identified as some of the most discriminant taxa positively associated with T1 samples. This preliminary study corroborates the relationship between intestinal microbiota and ASD recently described in the literature.

Orally administered Odoribacter laneus improves glucose control and inflammatory profile in obese mice by depleting circulating succinate.

BACKGROUND: Succinate is produced by both human cells and by gut bacteria and couples metabolism to inflammation as an extracellular signaling transducer. Circulating succinate is elevated in patients with obesity and type 2 diabetes and is linked to numerous complications, yet no studies have specifically addressed the contribution of gut microbiota to systemic succinate or explored the consequences of reducing intestinal succinate levels in this setting. RESULTS: Using germ-free and microbiota-depleted mouse models, we show that the gut microbiota is a significant source of circulating succinate, which is elevated in obesity. We also show in vivo that therapeutic treatments with selected bacteria diminish the levels of circulating succinate in obese mice. Specifically, we demonstrate that Odoribacter laneus is a promising probiotic based on its ability to deplete succinate and improve glucose tolerance and the inflammatory profile in two independent models of obesity (db/db mice and diet-induced obese mice). Mechanistically, this is partly mediated by the succinate receptor 1. Supporting these preclinical findings, we demonstrate an inverse correlation between plasma and fecal levels of succinate in a cohort of patients with severe obesity. We also show that plasma succinate, which is associated with several components of metabolic syndrome including waist circumference, triglycerides, and uric acid, among others, is a primary determinant of insulin sensitivity evaluated by the euglycemic-hyperinsulinemic clamp. CONCLUSIONS: Overall, our work uncovers O. laneus as a promising next-generation probiotic to deplete succinate and improve glucose tolerance and obesity-related inflammation. Video Abstract.

An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites.

The spread of multidrug-resistant bacteria, such as the skin commensal Staphylococcus aureus, is a worldwide health challenge; new methods to counteract opportunistic pathogen growth and virulence are urgent. We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300). CFS influence was assessed towards the viability, metabolic activity, and ability to form biofilm of the MDR strain through optical density, alamarBlue assay, and crystal violet staining; their content in short-chain fatty acids, lactic acid, and proteins was analysed via high-resolution mass spectrometry and gas chromatography. All CFSs reduce viable and metabolically active S. aureus, being TIL more efficient compared to MRS in stimulating lactic acid bacteria metabolism and decreasing S. aureus biofilm formation. Particularly, the CFS from LJO02 grown in TIL has the best efficacy, revealing a high amount of lactic acid and 59 peculiar proteins; its effectiveness is partially maintained upon trypsin and proteinase K treatments, but not by pepsin and pH basification. Therefore, antagonistic CFSs may represent a strategic prevention approach, with bacteriotherapeutic and bio-repair potential.

Probiotics as Potential Biological Immunomodulators in the Management of Oral Lichen Planus: What's New?

Oral lichen planus (OLP) is a T cell-mediated chronic inflammatory disorder with multifactorial aetiology and malignant transformation potential. Despite the treatments so far identified, new tailored and safe specific measures are needed. Recently, human microbiota imbalance has been linked to several immune-mediated diseases, opening new therapeutic perspectives for probiotics; besides their ability to directly interact with the host microbiota, they also display a strain-specific immune-modulatory effect. Thus, this non-systematic review aims to elucidate the molecular pathways underlying probiotic activity, mainly those of Lactobacilli and Bifidobacteria and their metabolites in OLP pathogenesis and malignant transformation, focusing on the most recent in vitro and in vivo research evidence. Findings related to their activity in other immune-mediated diseases are here included, suggesting a probiotic translational use in OLP. Probiotics show immune-modulatory and microbiota-balancing activities; they protect the host from pathogens, hamper an excessive effector T cell response, reduce nuclear factor-kappa B (NF-kB) signalling and basal keratinocytes abnormal apoptosis, shifting the mucosal response towards the production of anti-inflammatory cytokines, thus preventing uncontrolled damage. Therefore, probiotics could be a highly encouraging prevention and immunotherapeutic approach for a safer and more sustainable OLP management.

Probiotics-Supplemented Low-Protein Diet for Microbiota Modulation in Patients with Advanced Chronic Kidney Disease (ProLowCKD): Results from a Placebo-Controlled Randomized Trial.

The probiotics-supplemented low-protein diet in chronic kidney disease (ProLowCKD) was a single-centre, double-blind, placebo-controlled, randomised trial that was conducted to investigate whether the association between a low protein diet (LPD) and a new formulation of probiotics (Bifidobacterium longum and Lactobacillus reuteri) was effective at reducing traditional uremic, microbiota-derived, and proatherogenic toxins in sixty patients affected by advanced CKD. After 2 months of a LPD-a reduction in blood urea nitrogen (52 ± 17 vs. 46 ± 15 mg/dL, p = 0.003), total cholesterol (185 ± 41 vs. 171 ± 34 mg/dL, p = 0.001), and triglycerides (194 ± 148 vs. 161 ± 70 mg/dL, p = 0.03) was observed; 57 subjects were then randomized to receive probiotics or a placebo for the subsequent 3 months. A total of 27 patients in the placebo group showed increased serum values of total cholesterol (169 ± 36 vs. 185 ± 40 mg/dL, p = 0.01), LDL cholesterol (169 ± 36 vs. 185 ± 40 mg/dL, p = 0.02), lipoprotein-associated phospholipase A2 (155.4 ± 39.3 vs. 167.5 ± 51.4 nmol/mL/min, p = 0.006), and indoxyl-sulphate (30.1 ± 17.6 vs. 34.5 ± 20.2 µM, p = 0.026), while the 24 subjects in the probiotics group showed a trend in the reduction of microbiota toxins. A reduction of antihypertensive and diuretic medications was possible in the probiotics group. This study shows that associating probiotics to LPD may have an additional beneficial effect on the control and modulation of microbiota-derived and proatherogenic toxins in CKD patients.

The Probiotics in Pediatric Asthma Management (PROPAM) Study in the Primary Care Setting: A Randomized, Controlled, Double-Blind Trial with Ligilactobacillus salivarius LS01 (DSM 22775) and Bifidobacterium breve B632 (DSM 24706).

BACKGROUND: Type-2 inflammation commonly marks asthma in childhood. Also, gut and lung dysbiosis is detectable in patients with asthma. Strain-related probiotic supplementation may restore a physiological immune response, dampen airway inflammation, and repair dysbiosis. Therefore, the probiotics in pediatric asthma management (PROPAM) study is aimed at demonstrating that Ligilactobacillus salivarius LS01 (DSM 22775) and Bifidobacterium breve B632 (DSM 24706) mixture could reduce asthma exacerbations in children, followed in a primary care setting. METHODS: The study was randomized, placebo-controlled, and double-blind. It involved 11 Italian primary care pediatricians. The probiotic mixture (containing Ligilactobacillus salivarius LS01 1 × 109 live cells and Bifidobacterium breve B632 1 × 109 live cells) or placebo was taken twice daily (1 sachet in the morning and 1 in the evening) for eight weeks and subsequently once daily for a further eight weeks. Outcomes included number, severity, and duration of asthma exacerbations, intensity of maintenance and as need treatments, and safety. RESULTS: The per-protocol population included 422 children (mean age seven years, 240 males and 182 females). The probiotic mixture significantly reduced the number of asthmatic exacerbations (OR = 3.17). In addition, the number of children with two exacerbations was less than a third in the active group (OR = 3.65). CONCLUSIONS: This PROPAM study demonstrated that probiotic strains Ligilactobacillus salivarius LS01 (DSM 22775) and Bifidobacterium breve B632 (DSM 24706) were safe and significantly reduced by more than a third the frequency of asthma exacerbations. At present, the first-line treatment of asthma is still drug-based, but specific strains of probiotics may be auxiliary remedies.

Effectiveness of oral probiotics supplementation in the treatment of adult small chalazion.

AIM: To define the possible beneficial impact of probiotics oral supplementation on patients affected by chalazion. METHODS: Prospective comparative pilot study on 20 adults suffering from chalazion randomly divided into two groups. The first group (n=10) received conservative treatment with lid hygiene, warm compression, and dexamethasone/tobramycin ointment for at least 20d. The second group (n=10), in addition to the conservative treatment, received a mixture of probiotic microorganisms of Streptococcus thermophilus ST10 (DSM 25246), Lactococcus lactis LLC02 (DSM 29536) and Lactobacillus delbrueckii (DSM 16606) once a day up to 3mo. Chalazia were classified according to their size into three groups: small (<2 mm), medium (≥2 to <4 mm), or large (≥4 mm). When conservative treatment with and without probiotics supplementation failed to resolve the lesion, invasive methods were used, intralesional steroid injection in medium size chalazion and surgical incision and curettage for the largest ones. RESULTS: Medical treatment with or without probiotics supplementation was effective only on the small size chalazia. There was a significant difference in the time taken for complete resolution of small size chalazia between the two groups in favor of the patients receiving probiotics (38.50±9.04d vs 21.00±7.00d, P=0.039). Medium and large size chalazia did not respond to medical treatment with or without probiotics supplementation over the follow-up period (3mo). The treatment did not induce any complications in both groups and no recurrence of chalaziosis was recorded in both groups. CONCLUSION: The considerable difference in time taken for complete resolution of small chalazia between the two groups in favor of the experimental one confirms the presence of a gut-eye axis.

Facial Acne: A Randomized, Double-Blind, Placebo-Controlled Study on the Clinical Efficacy of a Symbiotic Dietary Supplement.

INTRODUCTION: Treatments other than topical and systemic antibiotics are needed to restore the dysbiosis correlated with acne onset and evolution. In this view, probiotics and botanical extracts could represent a valid adjunctive therapeutic approach. The purpose of this study was to test the efficacy of a dietary supplement containing probiotics (Bifidobacterium breve BR03 DSM 16604, Lacticaseibacillus casei LC03 DSM 27537, and Ligilactobacillus salivarius LS03 DSM 22776) and botanical extract (lupeol from Solanum melongena L. and Echinacea extract) in subjects with mild to moderate acne over an 8-week study period. METHODS: Monocentric, randomized, double-blind, four-arm, placebo-controlled clinical study involving 114 subjects. RESULTS: A significant (p < 0.05) effect on the number of superficial inflammatory lesions was reported over the study period in the subjects taking the study agent (group II) (-56.67%), the botanical extracts (group III) (-40.00%), and the probiotics (group IV) (-38.89%) versus placebo (-10.00%). A significant (p < 0.05) decrease in mean desquamation score, sebum secretion rate, and porphyrin mean count versus baseline was also reported, and the effect was most evident for group II. The analysis of log relative abundance after 4 and 8 weeks of treatment compared with baseline showed a significant (p < 0.01) decrease in Cutibacterium acnes and S. aureus, along with a contextually and significant (p < 0.05) increase in Staphylococcus epidermidis, especially in group II. No significant changes were reported for group I. CONCLUSION: The results from this study suggest that the administration of the dietary supplement under study was effective, safe, and well tolerated in subjects with mild to moderate acne and could represent a promising optional complement for the treatment of inflammatory acne as well as for control of acne-prone skin.

Assessing Gut Microbiota in an Infant with Congenital Propionic Acidemia before and after Probiotic Supplementation.

Propionic Acidemia (PA) is a rare inherited metabolic disorder caused by the enzymatic block of propionyl-CoA carboxylase with the consequent accumulation of propionic acid, which is toxic for the brain and cardiac cells. Since a considerable amount of propionate is produced by intestinal bacteria, interest arose in the attempt to reduce propionate-producing bacteria through a monthly antibiotic treatment of metronidazole. In the present study, we investigated the gut microbiota structure of an infant diagnosed at 4 days of life through Expanded Newborn Screening (NBS) and treated the child following international guidelines with a special low-protein diet, specific medications and strict biochemical monitoring. Microbiota composition was assessed during the first month of life, and the presence of Bacteroides fragilis, known to be associated with propionate production, was effectively decreased by metronidazole treatment. After five antibiotic therapy cycles, at 4 months of age, the infant was supplemented with a daily mixture of three bifidobacterial strains, known not to be propionate producers. The supplementation increased the population of bifidobacteria, with Bifidobacterium breve as the dominating species; Ruminococcus gnavus, an acetate and formate producer, was also identified. Metabarcoding analysis, compared with low coverage whole metagenome sequencing, proved to capture all the microbial biodiversity and could be the elected tool for fast and cost-effective monitoring protocols to be implemented in the follow up of rare metabolic disorders such as PA. Data obtained could be a possible starting point to set up tailored microbiota modification treatment studies in the attempt to improve the quality of life of people affected by propionic acidemia.

Supplementation with Bifidobacterium breve BR03 and B632 strains improved insulin sensitivity in children and adolescents with obesity in a cross-over, randomized double-blind placebo-controlled trial.

BACKGROUND & AIMS: Variations in gut microbiota might impact metabolism leading to body weight excess. We assessed the impact of a probiotic supplementation in pediatric obesity on weight, metabolic alterations, selected gut microbial groups, and functionality. METHODS: Cross-over, double-blind, randomized control trial (BIFI-OBESE trial; NCT03261466). 101 youths (6-18 years, Tanner stage ≥2) with obesity and insulin-resistance on diet were randomized to 2 × 109 CFU/AFU/day of Bifidobacterium breve BR03 (DSM 16604) and B. breve B632 (DSM 24706) (51) or placebo (50) for 8 weeks with a 4-weeks wash-out period. RESULTS: All subjects (M/F 54/47) completed the first 8 weeks, and 82 (M/F 43/39) the last part without adverse events. Mixed-effects models revealed a carry-over effect on many variables in the entire study, narrowing the analysis to the first 8 weeks before the wash-out periods. All subjects improved metabolic parameters, and decreased weight and Escherichia coli counts. Probiotics improved insulin sensitivity at fasting (QUICKI, 0.013 CI95%0.0-0.03) and during OGTT (ISI, 0.654 CI95%-0.11-1.41). Cytokines, GLP1, and target microbial counts did not vary. Of 25 SCFAs, acetic acid and acetic acid pentyl-ester relative abundance remained stable in the probiotics, while increased in the placebo (p < 0.02). A signature of five butanoic esters identified three clusters, one of them had better glucose responses during probiotics. CONCLUSION: An 8 weeks treatment with B. breve BR03 and B632 had beneficial effects on insulin sensitivity in youths with obesity. Microbiota functionality could influence metabolic answers to probiotics. Long-term studies to confirm and enrich our findings are justified. Tailored probiotic treatments could be an additional strategy for obesity. TRIAL REGISTRATION: NCT03261466.

Probiotics Supplements Reduce ER Stress and Gut Inflammation Associated with Gliadin Intake in a Mouse Model of Gluten Sensitivity.

Exposure to gluten, a protein present in wheat rye and barley, is the major inducer for human Celiac Disease (CD), a chronic autoimmune enteropathy. CD occurs in about 1% worldwide population, in genetically predisposed individuals bearing human leukocyte antigen (HLA) DQ2/DQ8. Gut epithelial cell stress and the innate immune activation are responsible for the breaking oral tolerance to gliadin, a gluten component. To date, the only treatment available for CD is a long-term gluten-free diet. Several studies have shown that an altered composition of the intestinal microbiota (dysbiosis) could play a key role in the pathogenesis of CD through the modulation of intestinal permeability and the regulation of the immune system. Here, we show that gliadin induces a chronic endoplasmic reticulum (ER) stress condition in the small intestine of a gluten-sensitive mouse model and that the coadministration of probiotics efficiently attenuates both the unfolded protein response (UPR) and gut inflammation. Moreover, the composition of probiotics formulations might differ in their activity at molecular level, especially toward the three axes of the UPR. Therefore, probiotics administration might potentially represent a new valuable strategy to treat gluten-sensitive patients, such as those affected by CD.

Oral microbiota and vitamin D impact on oropharyngeal squamous cell carcinogenesis: a narrative literature review.

An emerging body of research is revealing the microbiota pivotal involvement in determining the health or disease state of several human niches, and that of vitamin D also in extra-skeletal regions. Nevertheless, much of the oral microbiota and vitamin D reciprocal impact in oropharyngeal squamous cell carcinogenesis (OPSCC) is still mostly unknown. On this premise, starting from an in-depth scientific bibliographic analysis, this narrative literature review aims to show a detailed view of the state of the art on their contribution in the pathogenesis of this cancer type. Significant differences in the oral microbiota species quantity and quality have been detected in OPSCC-affected patients; in particular, mainly high-risk human papillomaviruses (HR-HPVs), Fusobacterium nucleatum, Porphyromonas gingivalis, Pseudomonas aeruginosa, and Candida spp. seem to be highly represented. Vitamin D prevents and fights infections promoted by the above identified pathogens, thus confirming its homeostatic function on the microbiota balance. However, its antimicrobial and antitumoral actions, well-described for the gut, have not been fully documented for the oropharynx yet. Deeper investigations of the mechanisms that link vitamin D levels, oral microbial diversity and inflammatory processes will lead to a better definition of OPSCC risk factors for the optimization of specific prevention and treatment strategies.