Effectiveness of prophylactic oral and/or vaginal probiotic supplementation in the prevention of recurrent urinary tract infections: A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Widespread antibiotic resistance has sparked interest in the lookout for non-antibiotic strategies, particularly focusing on probiotics for the prevention of recurrent urinary tract infections (UTIs). We evaluated the effectiveness of prophylactic probiotic supplementation through oral and intravaginal routes in the prevention of recurrent UTIs. METHODS: This double-blind, placebo-controlled study enrolled 174 premenopausal women with a history of recurrent UTIs and randomized them to either of the four treatment groups, namely, Placebo (G1, oral placebo+vaginal placebo); Oral probiotic (G2, oral lactic acid bacteria and bifidobacteria+vaginal placebo); Vaginal probiotic (G3, oral placebo+vaginal lactobacilli); and Probiotic combination (oral lactic acid bacteria and bifidobacteria+vaginal lactobacilli), for 4 months. Participants were followed-up for symptomatic UTIs for one year. The primary endpoints were the number of symptomatic UTIs at 4 months, the proportion of subjects with at least one symptomatic UTI, and the time to the first symptomatic UTI. RESULTS: The incidence of UTI at 4 months in G1, G2, G3 and G4 was 70.4%, 61.3%, 40.9%, and 31.8%, respectively. The mean number of symptomatic UTI recurrence at 4 months was significantly lower (p<0.05) in G3 (1.06) and G4 (1.07) compared to G1 (2.1) and G2 (1.63). Further, the time to first symptomatic UTI (days) was significantly longer (p<0.05) in G3 (123.8) and G4 (141.8) compared to G1 (69.3) and G2 (71.9). Probiotic supplementations were well tolerated with no serious adverse events. CONCLUSION: Prophylactic supplementation with either vaginal probiotics or in combination with oral probiotics demonstrated effectiveness in preventing recurrent symptomatic UTI episodes.

Faecalibacterium prausnitzii is not decreased in symptomatic uncomplicated diverticular disease of the colon.

In this letter, assessment of the amount of fecal Faecalibacterium prausnitzii in symptomatic uncomplicated diverticular disease (SUDD) is described. Among 44 consecutive patients, comprising 15 SUDD patients, 13 patients with asymptomatic diverticulosis (AD), and 16 healthy controls (HC), the fecal amount of Faecalibacterium prausnitzii was not found to be significantly different between HC, AD and SUDD subjects (p=0.871). Moreover, its count in the HC microbiota (-4.57 ± 2.15) was lower compared with those in the AD (-4.11 ± 1.03) and SUDD subjects (-4.03 ± 1.299). This behavior seems to be different from that occurring in inflammatory bowel disease (IBD) and similar to that of other mucin-degrading species in a SUDD setting.

Are Fecal Metabolome and Microbiota Profiles Correlated with Autism Severity? A Cross-Sectional Study on ASD Preschoolers.

Autism spectrum disorders (ASD) make up a heterogeneous group of neurodevelopmental disorders characterized by social and communication difficulties associated with repetitive and restrictive behaviors. Besides core features, metabolic imbalances, inflammation, gastrointestinal (GI) symptoms, and altered gut microbiota composition were often described in association with ASD, but their connection with the severity of autism (SA) remains unexplored. In this study, fecal metabolome, microbiota, and calprotectin levels of 80 ASD preschoolers were quantified and correlated with SA. Twelve of the fifty-nine molecules that were quantified by fecal metabolome analysis were significantly associated with SA. No links between SA or GI symptoms and microorganisms' relative abundance were highlighted. Significant correlations between bifidobacteria, Sutterella, lactobacilli relative abundance, and metabolomics profiles were found. These results suggest that fecal metabolome discriminates the SA and intestinal microorganisms mediate the link between metabolome and SA regardless of GI symptomatology. The study raises the possibility that grouping ASD populations through metabolomics and fecal microbiota could aid the identification of specific ASD endophenotypes, on the basis of the SA. Mechanistic studies focusing on detected biomarkers might be an option for future studies.

Probiotics combined with rifaximin influence the neurometabolic changes in a rat model of type C HE.

Type C hepatic encephalopathy (HE) is a neuropsychiatric disease caused by chronic liver disease. Management of type C HE remains an important challenge because treatment options are limited. Both the antibiotic rifaximin and probiotics have been reported to reduce the symptoms of HE, but longitudinal studies assessing their effects on brain metabolism are lacking and the molecular mechanisms underpinning their effects are not fully understood. Therefore, we evaluated in detail the effects of these different treatments on the neurometabolic changes associated with type C HE using a multimodal approach including ultra-high field in vivo 1H MRS. We analyzed longitudinally the effect of rifaximin alone or in combination with the probiotic Vivomixx on the brain metabolic profile in the hippocampus and cerebellum of bile duct ligated (BDL) rats, an established model of type C HE. Overall, while rifaximin alone appeared to induce no significant effect on the neurometabolic profile of BDL rats, its association with the probiotic resulted in more attenuated neurometabolic alterations in BDL rats followed longitudinally (i.e. a smaller increase in Gln and milder decrease in Glu and Cr levels). Given that both rifaximin and some probiotics are used in the treatment of HE, the implications of these findings may be clinically relevant.

Can Resveratrol-Inhaled Formulations Be Considered Potential Adjunct Treatments for COVID-19?

The pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has led to an extraordinary threat to the global healthcare system. This infection disease, named COVID-19, is characterized by a wide clinical spectrum, ranging from asymptomatic or mild upper respiratory tract illness to severe viral pneumonia with fulminant cytokine storm, which leads to respiratory failure. To improve patient outcomes, both the inhibition of viral replication and of the unwarranted excessive inflammatory response are crucial. Since no specific antiviral drug has been proven effective for the treatment of patients and the only upcoming promising agents are monoclonal antibodies, inexpensive, safe, and widely available treatments are urgently needed. A potential anti-inflammatory molecule to be evaluated, which possesses antiviral activities in several experimental models, is the polyphenol resveratrol. This compound has been shown to inhibit SARS-CoV-2 replication in human primary bronchial epithelial cell cultures and to downregulate several pathogenetic mechanisms involved in COVID-19 severity. The use of resveratrol in clinical practice is limited by the low bioavailability following oral administration, due to the pharmacokinetic and metabolic characteristics of the molecule. Therefore, topical administration through inhaled formulations could allow us to achieve sufficiently high concentrations of the compound in the airways, the entry route of SARS-CoV-2.

Probiotics improve the neurometabolic profile of rats with chronic cholestatic liver disease.

Chronic liver disease leads to neuropsychiatric complications called hepatic encephalopathy (HE). Current treatments have some limitations in their efficacy and tolerability, emphasizing the need for alternative therapies. Modulation of gut bacterial flora using probiotics is emerging as a therapeutic alternative. However, knowledge about how probiotics influence brain metabolite changes during HE is missing. In the present study, we combined the advantages of ultra-high field in vivo 1H MRS with behavioural tests to analyse whether a long-term treatment with a multistrain probiotic mixture (VIVOMIXX) in a rat model of type C HE had a positive effect on behaviour and neurometabolic changes. We showed that the prophylactic administration of this probiotic formulation led to an increase in gut Bifidobacteria and attenuated changes in locomotor activity and neurometabolic profile in a rat model of type C HE. Both the performance in behavioural tests and the neurometabolic profile of BDL + probiotic rats were improved compared to the BDL group at week 8 post-BDL. They displayed a significantly lesser increase in brain Gln, a milder decrease in brain mIns and a smaller decrease in neurotransmitter Glu than untreated animals. The clinical implications of these findings are potentially far-reaching given that probiotics are generally safe and well-tolerated by patients.

Bacterial-Based Strategies to Hydrolyze Gluten Peptides and Protect Intestinal Mucosa.

Gluten is a mixture of proteins highly resistant to hydrolysis, resulting in the emergence of toxic peptides responsible for gluten-related disorders. Currently, a gluten-free diet (GFD) is the unique proven therapy for celiac disease (CD). Several research groups and pharmaceutical companies are developing new nondietetic therapeutic strategies for CD. Probiotics are viable microorganisms thought to have a healthy effect on the host. The proteolytic mechanism of lactic acid bacteria comprises an extracellular serine protease, di- and oligopeptide-specific transport systems, and several intracellular peptidases that might affect gluten degradation. Therefore, probiotic supplementation is an attractive therapy because of its possible anti-inflammatory and immunomodulatory properties. Several studies have been performed to assess the effectiveness of various specific probiotic strains, showing positive effects on immune-modulation (inhibition of pro-inflammatory cytokine TNF-α) restoring gut microbiota and decrease of immunogenic peptides. The present review aims to summarize the current knowledge on the ability of probiotic strain (single or mixtures) to digest gliadin peptides in vitro and to modulate the inflammatory response in the gut.

Effects of Probiotic Supplementation on Gastrointestinal, Sensory and Core Symptoms in Autism Spectrum Disorders: A Randomized Controlled Trial.

The microbiota-gut-brain axis has been recently recognized as a key modulator of neuropsychiatric health. In this framework, probiotics (recently named "psychobiotics") may modulate brain activity and function, possibly improving the behavioral profiles of children with Autism Spectrum Disorder (ASD). We evaluated the effects of probiotics on autism in a double-blind randomized, placebo-controlled trial of 85 preschoolers with ASD (mean age, 4.2 years; 84% boys). Participants were randomly assigned to probiotics (De Simone Formulation) (n=42) or placebo (n=43) for six months. Sixty-three (74%) children completed the trial. No differences between groups were detected on the primary outcome measure, the Total Autism Diagnostic Observation Schedule - Calibrated Severity Score (ADOS-CSS). An exploratory secondary analysis on subgroups of children with or without Gastrointestinal Symptoms (GI group, n= 30; NGI group, n=55) revealed in the NGI group treated with probiotics a significant decline in ADOS scores as compared to that in the placebo group, with a mean reduction of 0.81 in Total ADOS CSS and of 1.14 in Social-Affect ADOS CSS over six months. In the GI group treated with probiotics we found greater improvements in some GI symptoms, adaptive functioning, and sensory profiles than in the GI group treated with placebo. These results suggest potentially positive effects of probiotics on core autism symptoms in a subset of ASD children independent of the specific intermediation of the probiotic effect on GI symptoms. Further studies are warranted to replicate and extend these promising findings on a wider population with subsets of ASD patients which share targets of intervention on the microbiota-gut-brain axis. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT02708901.

Therapeutic potential of resveratrol against emerging respiratory viral infections.

Resveratrol has been widely studied for its therapeutic potential due to its antioxidant, anti-inflammatory and anti-microbial properties. In particular, resveratrol has shown promising antiviral activity against numerous viruses responsible for severe respiratory infections. Amongst these, influenza virus, respiratory syncytial virus and the emerging SARS-cov-2 are known to cause pneumonia, acute respiratory distress syndrome or multi-organ failure, especially, in vulnerable individuals like immunocompromised patients or the elderly, leading to a considerable economic burden worldwide. In this context, resveratrol may have potential value for its anti-inflammatory activity, since most of the severe virus-associated complications are related to the overactivation of the host-immune response, leading to lung damage. Herein, we present an overview of the antiviral activity and potential mechanisms of resveratrol against the respiratory tract viruses considered as a public threat for their rapid transmission and high morbidity and mortality in the general population.

Resveratrol plus carboxymethyl-ß-glucan in infants with common cold: A randomized double-blind trial.

OBJECTIVES: To evaluate effectiveness of a nasal resveratrol/carboxymethyl-ß-glucan solution compared to nasal saline solution: a) on common cold symptoms by means of a validated measure scale (CARIFS score), b) on Rhinovirus infection and CCL2, CCL5, IL8, IL6, CXCL10 and TLR2 expression in nasal swabs, c) on frequency of relapses after 30 days of follow-up. METHODS: 89 infants with respiratory infection symptoms were randomly assigned to receive either a nasal resveratrol/carboxymethyl-ß-glucan solution or nasal saline solution.All patients were evaluated with CARIFS score at enrollment, after 48 h, 7 and 30 days by physicians and parents. Nasal swabs were obtained at enrollment, after 48 h and after one week. RESULTS: CARIFS score improved in both groups. Episodes of sneezing and cough were fewer in study group after 7 days of follow-up (p < 0.05). No significant differences were found on nasopharyngeal swabs in Rhinovirus detection and cytokines expression after 48 h, nor in 30 days relapses. TLR2 expression was significantly higher in Rhinovirus infected children of the study group. No adverse effects occurred. CONCLUSIONS: These data suggest that a solution containing resveratrol plus carboxymethyl-ß-glucan might have a positive impact on both clinical and socio-economic burden due to infant common cold.

A Probiotic Preparation Hydrolyzes Gliadin and Protects Intestinal Cells from the Toxicity of Pro-Inflammatory Peptides.

Celiac disease (CD) is an autoimmune enteropathy caused by an intolerance to gluten proteins. It has been hypothesized that probiotic bacteria may exert beneficial effects by modulating inflammatory processes and by sustaining peptide hydrolysis at the intestinal level. This study aims at evaluating the capacity of a probiotic mixture (two different strains of lactobacilli and three of bifidobacteria) to hydrolyze gluten peptides following simulated gastrointestinal digestion of gliadin (PT-gliadin). The capacity of bacterial hydrolysates to counteract the toxic effects of gliadin-derived peptides in Caco-2 cells was also assessed. The protein and peptide mixtures, untreated or proteolyzed with the probiotic preparation, were analyzed before and after each proteolytic step with different techniques (SDS-PAGE, reverse phase HPLC, filtration on different molecular cut-off membranes). These experiments demonstrated that PT-gliadin can be further digested by bacteria into lower molecular weight peptides. PT-gliadin, untreated or digested with the probiotics, was then used to evaluate oxidative stress, IL-6 cytokine production and expression of tight junctions' proteins-such as occludin and zonulin-in Caco-2 cells. PT-gliadin induced IL-6 production and modulation and redistribution of zonulin and occludin, while digestion with the probiotic strains reversed these effects. Our data indicate that this probiotic mixture may exert a protective role in CD.

A prophylactic multi-strain probiotic treatment to reduce the absorption of toxic elements: In-vitro study and biomonitoring of breast milk and infant stools.

Potential exposure to toxic elements initially occurs during gestation and after birth via breast milk, which is the principal source of nutrients for infants during the first months of life. In this study, we evaluated whether maternal oral supplementation with a multi-strain probiotic product can protect infants from exposure to arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) via breast milk. In-vitro studies of the bacterial strains present in this probiotic product showed a high bacterial tolerance for As, Cd, Hg, and Pb, and good binding capacity for Cd, Hg, and Pb (72%, 81%, and 64%, respectively) within 1 h of contact. We evaluated concentrations (5 mg L-1 for Cd and Pb, and 2 mg L-1 for Hg) that largely exceeded the provisional tolerable weekly intake of these toxic elements via food or water applicable for human consumption. Changes in the levels of these elements in breast milk and newborn stools were evaluated in the control (orally supplemented with placebo) and experimental (orally supplemented with probiotic) groups at birth (t0), 15 days (t15), and 30 days (t30) after delivery. Elemental analysis of breast milk did not show significant differences between the control and experimental groups at different stages of lactation; however, stool samples obtained from newborns of mothers supplemented with the probiotic product showed that Cd levels were significantly reduced (by 26%) at t15 compared with the levels of the controls. Our data did not show an association between concentration of toxic elements in breast milk and that in newborn stools. Indeed, the concentration of Cd, Hg, and Pb in breast milk decreased during the lactation period, whereas the levels of these elements in newborn stools were stable over time. Although our in-vitro data indicate that the consortium of these probiotic strains can absorb toxic compounds, this study was limited by its small sample size and potential uncontrolled confounding effects, such as maternal diet and lifestyle. Therefore, we could not confirm whether prophylactic use of this probiotic product can reduce the absorption of toxic elements. The risk assessment in the studied population evidenced a margin of exposure (MOE) of 1, or between 1 and 10 for Pb, and lower than 50 for As. This poses a potential risk for breastfed infants, indicating that interventions aimed to avoid breastfeeding-related health risks remain a major challenge in public health.

Rationale of Probiotic Supplementation during Pregnancy and Neonatal Period.

Probiotics are living microorganisms that confer a health benefit when administered in adequate amounts. It has been speculated that probiotics supplementation during pregnancy and in the neonatal period might reduce some maternal and neonatal adverse outcomes. In this narrative review, we describe the rationale behind probiotic supplementation and its possible role in preventing preterm delivery, perinatal infections, functional gastrointestinal diseases, and atopic disorders during early life.

Optimization and validation of a fast digestion method for the determination of major and trace elements in breast milk by ICP-MS.

Breast milk guarantees all the nutrients required by infants during their first few months of life and remains the most important food source for their health and growth. However, the mother may transfer potentially toxic chemicals to the suckling infant through breastfeeding. The aim of this study was to optimize and validate a fast method for the determination of a total content of 34 elements (Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sb, Se, Si, Sn, Sr, Te, Ti, Tl, U, V, and Zn) in liquid and lyophilized breast milk. The samples were subjected to HNO3:H2O2 (2:1) digestion in an open vessel heated in a water bath (WBD; 80 °C) and subsequently analysed by quadrupole inductively coupled plasma mass spectrometry equipped with a collision-reaction interface. The performance of the proposed method was evaluated in terms of selectivity, detection and quantification limits, linearity, accuracy, and robustness by using standard reference materials and filed samples of breast milk. Compared to microwave-assisted acid digestion, the proposed open vessel digestion allows a significant reduction in treatment time and sample manipulation, while maintaining a similar analytical performance. Masses of 0.5 g of breast milk were efficiently digested with the WBD treatment allowing a residual carbon content lower than 60 mg L-1 and a residual acidity lower than 0.87 mol L-1 in final digested samples. Thus, it shows great potential for application to routine analysis. The method provides satisfactory detection limits and good performance (trueness and recovery percentages 80-111%; coefficient of variation <10%; and relative repeatability <15%) and allows a high sample throughput for multi-elemental determination in human biomonitoring studies.

Role of Lactobacilli and Lactoferrin in the Mucosal Cervicovaginal Defense.

The innate defense system of the female mucosal genital tract involves a close and complex interaction among the healthy vaginal microbiota, different cells, and various proteins that protect the host from pathogens. Vaginal lactobacilli and lactoferrin represent two essential actors in the vaginal environment. Lactobacilli represent the dominant bacterial species able to prevent facultative and obligate anaerobes outnumber in vaginal microbiota maintaining healthy microbial homeostasis. Several mechanisms underlie the protection exerted by lactobacilli: competition for nutrients and tissue adherence, reduction of the vaginal pH, modulation of immunity, and production of bioactive compounds. Among bioactive factors of cervicovaginal mucosa, lactoferrin, an iron-binding cationic glycoprotein, is a multifunctional glycoprotein with antibacterial, antifungal, antiviral, and antiparasitic activities, recently emerging as an important modulator of inflammation. Lactobacilli and lactoferrin are largely under the influence of female hormones and of paracrine production of various cytokines. Lactoferrin is strongly increased in lower genital tract mucosal fluid of women affected by Neisseria gonorrheae, Chlamydia trachomatis, and Trichomonas vaginalis infections promoting both innate and adaptive immune responses. In vaginal dysbiosis characterized by low amounts of vaginal lactobacilli and increased levels of endogenous anaerobic bacteria, the increase in lactoferrin could act as an immune modulator assuming the role normally played by the healthy microbiota in vaginal mucosa. Then lactoferrin and lactobacilli may be considered as biomarkers of altered microbial homeostasis at vaginal level. Considering the shortage of effective treatments to counteract recurrent and/or antibiotic-resistant bacterial infections, the intravaginal administration of lactobacilli and lactoferrin could be a novel efficient therapeutic strategy and a valuable tool to restore mucosal immune homeostasis.

Effectiveness and Safety of a Probiotic-Mixture for the Treatment of Infantile Colic: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial with Fecal Real-Time PCR and NMR-Based Metabolomics Analysis.

INTRODUCTION: To investigate the effectiveness and the safety of a probiotic-mixture (Vivomixx®, Visbiome®, DeSimone Formulation®; Danisco-DuPont, Madison, WI, USA) for the treatment of infantile colic in breastfed infants, compared with a placebo. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in exclusively breastfed infants with colic, randomly assigned to receive a probiotic-mixture or a placebo for 21 days. A structured diary of gastrointestinal events of the infants was given to the parents to complete. Samples of feces were also collected to evaluate microbial content and metabolome using fecal real-time polymerase chain reaction (qPCR) and Nuclear magnetic resonance (NMR)-based analysis. Study registered at ClinicalTrials.gov (NCT01869426). RESULTS: Fifty-three exclusively-breastfed infants completed three weeks of treatment with a probiotic-mixture (n = 27) or a placebo (n = 26). Infants receiving the probiotic-mixture had less minutes of crying per day throughout the study by the end of treatment period (68.4 min/day vs. 98.7 min/day; p = 0.001). A higher rate of infants from the probiotic-mixture group responded to treatment (defined by reduction of crying times of ≥50% from baseline), on day 14, 12 vs. 5 (p = 0.04) and on day 21, 26 vs. 17 (p = 0.001). A higher quality of life, assessed by a 10-cm visual analogue scale, was reported by parents of the probiotic-mixture group on day 14, 7.1 ± 1.2 vs. 7.7 ± 0.9 (p = 0.02); and on day 21, 6.7 ± 1.6 vs. 5.9 ± 1.0 (p = 0.001). No differences between groups were found regarding anthropometric data, bowel movements, stool consistency or microbiota composition. Probiotics were found to affect the fecal molecular profile. No adverse events were reported. CONCLUSIONS: Administration of a probiotic-mixture appears safe and reduces inconsolable crying in exclusively breastfed infants.

Efficacy and Safety of a Multistrain Probiotic Formulation Depends from Manufacturing.

BACKGROUND: Variability in probiotics manufacturing may affect their properties, with potential implications for their efficacy and safety. This is of particular concern with probiotic products destined for use in patients with serious medical conditions, including human immunodeficiency virus (HIV) infection. The purpose of the study was to carry out a series of experiments comparing the properties of the US-made probiotic formulation originally commercialized under the brand name VSL#3®, with those of the Italian-made formulation now commercialized under the same name. The US-made formulation has previously shown beneficial effects at the intestinal and neurological levels in HIV-infected subjects as well as in patients with inflammatory bowel diseases and hepatic encephalopathy. METHODS: Eleven subjects receiving combined antiretroviral therapy for HIV-1 were treated for 6 months with the US-made VSL#3 formulation. At baseline and 6 months, T-cells were analyzed for phenotype and activation markers, and fecal samples were analyzed for bifidobacteria, lactobacilli, and their metabolites. The fecal metabolome was assessed using 1H-NMR spectroscopy. Production of metabolites of interest by bacteria obtained from sachets of the two formulations was compared in vitro and their effects on a rat intestinal epithelial cell line (IEC-6) were assessed. Particular attention was paid to the metabolite 1,3-dihydroxyacetone (DHA). RESULTS: At 6 months, fecal samples showed a significant increase in the specific bacterial genera contained in the probiotic supplement. Immune activation was reduced as shown by a significant reduction in the percentage of CD4+CD38+HLA-DR+ T-cells at 6 months. Fecal concentrations of DHA decreased significantly. In vitro, significant differences in the production and metabolism of DHA were found between bacteria from the US-made and Italian-made formulations: the US-made formulation was able to metabolize DHA whereas the bacteria in the Italian-made formulation were producing DHA. DHA reduced the viability of Streptococcus thermophilus, reduced IEC-6 cell viability in a dose-dependent manner, and also led to a lower rate of repair to scratched IEC-6 cell monolayer. CONCLUSION: Our data, in conjunction with previously published findings, confirm that the new Italian-made formulation of VSL#3® is different from the previous US-made VSL#3 and therefore its efficacy and safety in HIV-infected subjects is still unproven.

Probiotic supplementation promotes a reduction in T-cell activation, an increase in Th17 frequencies, and a recovery of intestinal epithelium integrity and mitochondrial morphology in ART-treated HIV-1-positive patients.

INTRODUCTION: HIV infection is characterized by a persistent immune activation associated to a compromised gut barrier immunity and alterations in the profile of the fecal flora linked with the progression of inflammatory symptoms. The effects of high concentration multistrain probiotic (Vivomixx®, Viale del Policlinico 155, Rome, Italy in EU; Visbiome®, Dupont, Madison, Wisconsin in USA) on several aspects of intestinal immunity in ART-experienced HIV-1 patients was evaluated. METHODS: A sub-study of a longitudinal pilot study was performed in HIV-1 patients who received the probiotic supplement twice a day for 6 months (T6). T-cell activation and CD4+ and CD8+ T-cell subsets expressing IFNγ (Th1, Tc1) or IL-17A (Th17, Tc17) were stained by cytoflorimetric analysis. Histological and immunohistochemical analyses were performed on intestinal biopsies while enterocytes apoptosis index was determined by TUNEL assay. RESULTS: A reduction in the frequencies of CD4+ and CD8+ T-cell subsets, expressing CD38+ , HLA-DR+ , or both, and an increase in the percentage of Th17 cell subsets, especially those with central or effector memory phenotype, was recorded in the peripheral blood and in gut-associated lymphoid tissue (GALT) after probiotic intervention. Conversely, Tc1 and Tc17 levels remained substantially unchanged at T6, while Th1 cell subsets increase in the GALT. Probiotic supplementation was also associated to a recovery of the integrity of the gut epithelial barrier, a reduction of both intraepithelial lymphocytes density and enterocyte apoptosis and, an improvement of mitochondrial morphology sustained in part by a modulation of heat shock protein 60. CONCLUSIONS: These findings highlight the potential beneficial effects of probiotic supplementation for the reconstitution of physical and immunological integrity of the mucosal intestinal barrier in ART-treated HIV-1-positive patients.