Unveiling the Health Benefits of Prebiotics: A Comprehensive Review.

Prebiotics play a pivotal role in fostering probiotics, essential contributors to the creation and maintenance of a conducive environment for beneficial microbiota within the human gut. To qualify as a prebiotic, a substance must demonstrate resilience to stomach enzymes, acidic pH levels, and intestinal bacteria, remaining unabsorbed in the digestive system while remaining accessible to gut microflora. The integration of prebiotics and probiotics into our daily diet establishes a cornerstone for optimal health, a priority for health-conscious consumers emphasizing nutrition that supports a balanced gut flora. Prebiotics offer diverse biological functions in humans, exhibiting antiobesity, antimicrobial, anticancer, anti-inflammatory, antidiabetic, and cholesterol-lowering properties, along with preventing digestive disorders. Numerous dietary fibers possessing prebiotic attributes are inadvertently present in our diets, emphasizing the broader significance of prebiotics. It is crucial to recognize that, while all dietary fibers are prebiotics, not all prebiotics fall under the category of dietary fibers. The versatile applications of prebiotics extend across various industries, such as dairy, bakery, beverages, cosmetics, pharmaceuticals, and other food products. This comprehensive review provides insights into different prebiotics, encompassing their sources, chemical compositions, and applications within the food industry.

Probiotics for oral health: a critical evaluation of bacterial strains.

Oral health is critical for total body health and well-being; however, little improvement in oral health status has occurred in the U.S. over the past 20 years. Tooth decay and gum disease remain highly prevalent, with more than 90% and 50% of adults suffering from these conditions, respectively. To combat this lack of improvement, alternative approaches to dental care are now being suggested. One such alternative therapy is probiotics for oral care. In the oral cavity, probiotic strains have been shown to reduce levels of oral pathogens, inhibit the formation of dental caries, and reduce the levels of bacteria that cause halitosis. However, as the oral care probiotic market expands, many products contain bacterial species and strains with no documented health benefits leading to confusion and mistrust among consumers and clinicians. This confusion is enhanced by the regulatory status of probiotic products which puts the onus of safety and efficacy on the manufacturer rather than a central regulatory body. The overarching goal of this review is to provide consumers and clinicians with documented evidence supporting (or refuting) the health benefits of oral care probiotics marketed for sale in the United States. This includes defining what constitutes an oral care probiotic product and a strain level analysis of candidate probiotics from the genera Streptococcus, Lactobacillus, Bifidobacterium, and Bacillus. Additionally, prebiotics and postbiotics will be discussed. Finally, a set of considerations for consumers and clinicians is provided to empower probiotic product decision making. Together, this review will improve understanding of oral care probiotics marketed in the US for dental professionals and consumers.

Mechanisms and intervention of prebiotic foods in musculoskeletal health.

The review focuses primarily on collating and analysing the mechanistic research data that discusses the function of prebiotics to halt the frailty of musculoskeletal system. Musculoskeletal diseases (MSDs) are frequently reported to co-occur within their own categories of conditions, such as osteoarthritis, rheumatoid arthritis, gouty arthritis and psoriatic arthritis due to their overlapping pathogenesis. Consequently, the same drugs are often used to manage the complications of most types. A few recent studies have addressed the therapeutic functions of gut microbes towards those commonly shared MSD pathway targets. Improving microbial diversity and enriching their population in the gut would promote the regeneration and recovery of the musculoskeletal system. Prebiotics are usually non-digestible substrates that are selectively utilized/ digested by the gut microbes conferring health promotion. The microbial fermentation of prebiotics generates numerous host-beneficial therapeutic molecules. This study inspects the presumptive functions of plant-derived prebiotics for the growth and restoration of intestinal microbiota and the consequent improvement of skeletal health. The review also highlights the discrete functions of prebiotics against inflammation, autoimmunity, infection, physiological overloading mechanism and ageing-associated loss of metabolism in MSD.

Beneficial Effects of Synbiotics on the Gut Microbiome in Individuals with Low Fiber Intake: Secondary Analysis of a Double-Blind, Randomized Controlled Trial.

Insufficient dietary fiber intake can negatively affect the intestinal microbiome and, over time, may result in gut dysbiosis, thus potentially harming overall health. This randomized controlled trial aimed to improve the gut microbiome of individuals with low dietary fiber intake (<25 g/day) during a 7-week synbiotic intervention. The metabolically healthy male participants (n = 117, 32 ± 10 y, BMI 25.66 ± 3.1 kg/m2) were divided into two groups: one receiving a synbiotic supplement (Biotic Junior, MensSana AG, Forchtenberg, Germany) and the other a placebo, without altering their dietary habits or physical activity. These groups were further stratified by their dietary fiber intake into a low fiber group (LFG) and a high fiber group (HFG). Stool samples for microbiome analysis were collected before and after intervention. Statistical analysis was performed using linear mixed effects and partial least squares models. At baseline, the microbiomes of the LFG and HFG were partially separated. After seven weeks of intervention, the abundance of SCFA-producing microbes significantly increased in the LFG, which is known to improve gut health; however, this effect was less pronounced in the HFG. Beneficial effects on the gut microbiome in participants with low fiber intake may be achieved using synbiotics, demonstrating the importance of personalized synbiotics.

Symptoms and management of cow's milk allergy: perception and evidence.

Introduction: The diagnosis and management of cow's milk allergy (CMA) is a topic of debate and controversy. Our aim was to compare the opinions of expert groups from the Middle East (n = 14) and the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) (n = 13). Methods: These Expert groups voted on statements that were developed by the ESPGHAN group and published in a recent position paper. The voting outcome was compared. Results: Overall, there was consensus amongst both groups of experts. Experts agreed that symptoms of crying, irritability and colic, as single manifestation, are not suggestive of CMA. They agreed that amino-acid based formula (AAF) should be reserved for severe cases (e.g., malnutrition and anaphylaxis) and that there is insufficient evidence to recommend a step-down approach. There was no unanimous consensus on the statement that a cow's milk based extensively hydrolysed formula (eHF) should be the first choice as a diagnostic elimination diet in mild/moderate cases. Although the statements regarding the role for hydrolysed rice formula as a diagnostic and therapeutic elimination diet were accepted, 3/27 disagreed. The votes regarding soy formula highlight the differences in opinion in the role of soy protein in CMA dietary treatment. Generally, soy-based formula is seldom available in the Middle-East region. All ESPGHAN experts agreed that there is insufficient evidence that the addition of probiotics, prebiotics and synbiotics increase the efficacy of elimination diets regarding CMA symptoms (despite other benefits such as decrease of infections and antibiotic intake), whereas 3/14 of the Middle East group thought there was sufficient evidence. Discussion: Differences in voting are related to geographical, cultural and other conditions, such as cost and availability. This emphasizes the need to develop region-specific guidelines considering social and cultural conditions, and to perform further research in this area.

Colorectal cancer and inulin supplementation: the good, the bad, and the unhelpful.

The prebiotic inulin has been vaunted for its potential to reduce the risk of colorectal cancer. Inulin fermentation resulting in the production of short-chain fatty acids, primarily butyrate, has been reported to be associated with properties that are beneficial for gut health and has led to an increased consumption of inulin in the Western population through processed food and over-the-counter dietary supplements. However, in clinical trials, there is limited evidence of the efficacy of inulin in preventing colorectal cancer. Moreover, recent data suggest that improper inulin consumption may even be harmful for gastro-intestinal health under certain circumstances. The main objective of this review is to provide insight into the beneficial and potentially detrimental effects of inulin supplementation in the context of colorectal cancer prevention and enhancement of treatment efficacy.

Dietary fiber monosaccharide content alters gut microbiome composition and fermentation.

Members of the mammalian gut microbiota metabolize diverse complex carbohydrates that are not digested by the host, which are collectively labeled "dietary fiber." While the enzymes and transporters that each strain uses to establish a nutrient niche in the gut are often exquisitely specific, the relationship between carbohydrate structure and microbial ecology is imperfectly understood. The present study takes advantage of recent advances in complex carbohydrate structure determination to test the effects of fiber monosaccharide composition on microbial fermentation. Fifty-five fibers with varied monosaccharide composition were fermented by a pooled feline fecal inoculum in a modified MiniBioReactor array system over a period of 72 hours. The content of the monosaccharides glucose and xylose was significantly associated with the reduction of pH during fermentation, which was also predictable from the concentrations of the short-chain fatty acids lactic acid, propionic acid, and the signaling molecule indole-3-acetic acid. Microbiome diversity and composition were also predictable from monosaccharide content and SCFA concentration. In particular, the concentrations of lactic acid and propionic acid correlated with final alpha diversity and were significantly associated with the relative abundance of several of the genera, including Lactobacillus and Dubosiella. Our results suggest that monosaccharide composition offers a generalizable method to compare any dietary fiber of interest and uncover links between diet, gut microbiota, and metabolite production. IMPORTANCE: The survival of a microbial species in the gut depends on the availability of the nutrients necessary for that species to survive. Carbohydrates in the form of non-host digestible fiber are of particular importance, and the set of genes possessed by each species for carbohydrate consumption can vary considerably. Here, differences in the monosaccharides that are the building blocks of fiber are considered for their impact on both the survival of different species of microbes and on the levels of microbial fermentation products produced. This work demonstrates that foods with similar monosaccharide content will have consistent effects on the survival of microbial species and on the production of microbial fermentation products.

Ribosome-Free Translation up to Pentapeptides via Template Walk on RNA Sequences.

The origin of translation is one of the most difficult problems of molecular evolution. Identifying molecular systems that translate an RNA sequence into a peptide sequence in the absence of ribosomes and enzymes is a challenge. Recently, single-nucleotide translation via coupling of 5' phosphoramidate-linked amino acids to 2'/3'-aminoacyl transfer-NMPs, as directed by the sequence of an RNA template, was demonstrated for three of the four canonical nucleotides. How single-nucleotide translation could be expanded to include all four bases and to produce longer peptides without translocation along the template strand remained unclear. Using transfer strands of increasing length containing any of the four bases that interrogate adjacent positions along the template, we now show that pentapeptides can be produced in coupling reactions and subsequent hydrolytic release in situ. With 2'/3'-aminoacylated mono-, di, tri- and tetranucleotides we thus show just how efficient translation can be without biomacromolecules.

Determination of prebiotic properties of rice bran extract.

This research investigated and compared the prebiotic properties of a rice bran extract obtained through commercial xylanase extraction in comparison with water extraction. Prebiotic properties were evaluated by probiotic growth stimulation (Lacticaseibacillus casei and Lactiplantibacillus plantarum) and gastrointestinal pathogen inhibition (Bacillus cereus and Escherichia coli). The rice bran extract obtained with xylanase (RB1) displayed significantly higher total polysaccharide and total reducing sugar contents than those obtained with water (RB2; p<0.05). After extraction for 30 min, RB1 exhibited the highest total polysaccharide and total reducing sugar contents. HPLC (high performance liquid chromatography) analysis revealed that RB1 primarily contained xylose, while RB2 contained less glucose and lacked other sugar derivatives. RB1 proved effective in stimulating the growth of L. casei and L. plantarum, surpassing even inulin (a commercial prebiotic). Furthermore, it demonstrated a high potential for inhibiting the growth of pathogenic B. cereus and E. coli, comparable to inulin. In contrast, RB2 exhibited lower inhibitory capacity against B. cereus and E. coli.

Sucralose Influences the Productive Performance, Carcass Traits, Blood Components, and Gut Microflora Using 16S rRNA Sequencing of Growing APRI-Line Rabbits.

This study investigated how sucralose influenced rabbit intestine and caecal microbial activity, blood parameters, growth performance, carcass characteristics, and digestibility. In total, 160 5-week-old rabbits from the APRI line weighing 563.29 gm were randomly assigned to four experimental groups with four replicates-5 males and 5 females in each. Four experimental groups were used, as follows: SUC1, SUC2, and SUC3 got 75, 150, and 300 mg of sucralose/kg body weight in water daily, while the control group ate a basal diet without supplements. The results showed that both the control and SUC1 groups significantly (p < 0.05) increased daily weight gain and final body weight. Sucralose addition significantly improved feed conversion ratio (p < 0.05) and decreased daily feed intake (gm/d). The experimental groups do not significantly differ in terms of mortality. Furthermore, nutrient digestibility was not significantly affected by sucralose treatment, with the exception of crud protein digestion, which was significantly reduced (p < 0.05). Additionally, without altering liver or kidney function, sucralose administration dramatically (p < 0.05) decreased blood serum glucose and triglyceride levels while increasing total lipids, cholesterol, and malonaldehyde in comparison to the control group. Furthermore, the addition of sucrose resulted in a significant (p < 0.05) increase in the count of total bacteria, lactobacillus, and Clostridium spp., and a decrease in the count of Escherichia coli. Further analysis using 16S rRNA data revealed that sucralose upregulated the expression of lactobacillus genes but not that of Clostridium or E. Coli bacteria (p < 0.05). Therefore, it could be concluded that sucralose supplementation for rabbits modifies gut microbiota and boosts beneficial bacteria and feed conversion ratios without side effects. Moreover, sucralose could decrease blood glucose and intensify hypercholesterolemia and should be used with caution for human consumption.

Effects of Physicochemical and Biological Treatment on Structure, Functional and Prebiotic Properties of Dietary Fiber from Corn Straw.

Corn straw is one kind of agricultural by-product containing 70-80% insoluble dietary fiber (IDF). In order to develop corn straw dietary fiber, this study was conducted to increase soluble dietary fiber (SDF) yield and improve the structure, functional and prebiotic properties of IDF and SDF from corn straw treated by alkali oxidation treatment, enzymatic hydrolysis, microbial fermentation and the combination of these methods. The results demonstrated that the yield of SDF was significantly increased from 2.64% to 17.15% after corn straw was treated by alkali oxidation treatment + Aspergillus niger fermentation + cellulase hydrolysis, compared with untreated corn straw. The SDF extracted from corn straw treated by alkali oxidation treatment + Aspergillus niger fermentation + cellulase hydrolysis (F-SDF) exhibited a honeycomb structure, low crystallinity (11.97%), good antioxidant capacity and high capacities of water holding, water solubility and cholesterol absorption and promoted short-chain fatty acids production by chicken cecal microbial fermentation in vitro. F-SDF enhanced the antibacterial activity against Escherichia coli and Staphylococcus aureus proliferations of Lactobacillus plantarum when it was used as a substrate for Lactobacillus plantarum fermentation. It could be concluded that the combined treatments could increase SDF yield from corn straw and improve its functional and prebiotic properties.

The Efficacy of Probiotics, Prebiotics, Synbiotics, and Fecal Microbiota Transplantation in Irritable Bowel Syndrome: A Systematic Review and Network Meta-Analysis.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with gut microbiota imbalance playing a significant role. There are increasing numbers of research studies exploring treatment options involving probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT), but it is still uncertain which treatment option is superior. The research was conducted on various databases and unpublished trial data (up to February 2023). Randomized controlled trials (RCTs) were screened for adult patients with IBS comparing interventions with placebo. Probiotics, prebiotics, synbiotics, and FMT were assessed for their impact using mean difference and Bayesian network meta-analysis. Out of 6528 articles, 54 were included for probiotics, 7 for prebiotics/synbiotics, and 6 for FMT. Probiotics showed improvement in IBS symptoms, particularly with Bifidobacterium and Lactobacillus strains. Prebiotics and synbiotics did not show significant improvement. Network meta-analysis indicated the favorable effects of probiotics (OR = 0.53, 95% CI, 0.48 to 0.59) and FMT (OR = 0.46, 95% CI, 0.33 to 0.64) on IBS, with no serious adverse events reported. In short, probiotics and FMT are effective for managing IBS, with Bifidobacterium and Lactobacillus being dominant strains. However, the most effective probiotic combination or strain remains unclear, while prebiotics and synbiotics did not show significant improvement.

Photochemically Driven Peptide Formation in Supersaturated Aerosol Droplets.

The condensation of amino acids into peptides plays a crucial role in protein synthesis and is thus essential for understanding the origins of life. However, the spontaneous formation of peptides from amino acids in bulk aqueous media is energetically unfavorable, posing a challenge for elucidating plausible abiotic mechanisms. In this study, we investigate the formation of amide bonds between amino acids within highly supersaturated aerosol droplets containing dicyandiamide (DCD), a cyanide derivative potentially present on primordial Earth. Metastable states, i.e. supersaturation, within individual micron-sized droplets are studied using both an optical trap and a linear quadrupole electrodynamic balance. When irradiated with intense visible light, amide bond formation is observed to occur and can be monitored using vibrational bands in Raman spectra. The reaction rate is found to be strongly influenced by droplet size and kinetic modelling suggests that it is driven by the photochemical product of a DCD self-reaction. Our results highlight the potential of atmospheric aerosol particles as reaction environments for peptide synthesis and have potential implications for the prebiotic chemistry of early Earth.

Edible herbal source-derived polysaccharides as potential prebiotics: Composition, structure, gut microbiota regulation, and its related health effects.

Recently, with changes in dietary patterns, there has been increased interest in the concept of food and medicine homology, which can help prevent disease development. This has led to a growing focus on the development of functional health foods derived from edible herbal sources. Polysaccharides, found in many edible herbal sources, are gaining popularity as natural ingredients in the production of functional food products. The gut microbiota can effectively utilize most edible herbal polysaccharides (EHPs) and produce beneficial metabolites; therefore, the prebiotic potential of EHPs is gradually being recognized. In this review, we comprehensively discuss the structural features and characterization of EHPs to promote gut microbiota regulation as well as the structure-activity relationship between EHPs and gut microbiota. As prebiotics, intestinal microbiota can use EHPs to indirectly produce metabolites such as short-chain fatty acids to promote overall health; on the other hand, different EHP structures possess some degree of selectivity on gut microbiota regulation. Moreover, we evaluate the functionality and mechanism underlying EHPs in terms of anticancer activity, antimetabolic diseases, anti-inflammatory activity, and anti-neuropsychiatric diseases.

Exploring the relationship between gut microbiome modulation and blood pressure in type 2 diabetes: An umbrella review.

AIMS: Given the epidemic proportions of type 2 diabetes mellitus (T2DM) globally, it's crucial to comprehensively understand the factors influencing its management. The gut microbiome, known for its influence on various aspects of health, has emerged as a potential regulator of blood pressure in individuals with T2DM. This umbrella review aimed to consolidate the findings of existing meta-analyses investigating the impact of gut microbiome modulation on systolic and diastolic blood pressure in T2DM patients. DATA SYNTHESIS: Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we systematically searched PubMed, Scopus, and Web of Science databases from inception to July 2023. Quality assessment was performed using the AMSTAR2 and GRADE checklists. Statistical analyses were conducted using Comprehensive Meta-Analysis (CMA) version 3. A total of 6 meta-analyses meeting the inclusion criteria were included. The results revealed a significant association between microbial modulation and diastolic blood pressure (SMD: -0.133; 95% CI: -0.219 to -0.048; P = 0.002). However, the effect of gut microbial modulation on systolic blood pressure did not reach statistical significance (SMD: -0.077; 95% CI: -0.162 to 0.009; P = 0.078). CONCLUSION: This study found that modulating the gut microbiome had a statistically significant impact on diastolic blood pressure in individuals with type 2 diabetes mellitus (T2DM). However, no significant effect was observed on systolic blood pressure. While high-quality meta-analyses reported favorable outcomes, caution is warranted due to the low clinical importance, diversity in study populations, and variations in interventions.

Modulation of chicken gut microbiota for enhanced productivity and health: A review.

Microbiota in the digestive tract has become an interesting topic for researchers in recent years. The profile of chicken digestive tract microbiota and its relationship with health and production efficiency have become basic data for modulating the diversity and abundance of the digestive tract microbiota. This article reviews the techniques used to analyze the diversity, role, and function of the gastrointestinal microbiota and the mechanisms by which they are modulated. The gut microbiota plays an important role in animal production, especially during feed digestion and animal health, because it interacts with the host against pathogens. Feed modulation can be a strategy to modulate gut composition and diversity to increase production efficiency by improving growth conditions.

Exploratory analysis on the association of dietary live microbe and non-dietary prebiotic/probiotic intake with serum cotinine levels in the general adult population.

Background: Previous research has indicated the potential involvement of the microbiota in smoking-related processes. The present study seeks to examine the relationship between dietary live microbes, as well as probiotic or prebiotic consumption, and serum cotinine levels. Methods: This study used data from the National Health and Nutrition Examination Survey 1999-2018. Dietary intake information and probiotic/prebiotic intake data was collected through self-reported questionnaires. Participants were stratified into low, medium, and high intake groups according to their consumption of foods with varying microbial content. Multiple linear models were applied to explore the relationships of dietary live microbes, probiotic or prebiotic use with the serum cotinine level. Results: A total of 42,000 eligible participants were included in the final analysis. The weighted median serum cotinine level was 0.05 (0.01, 10.90) ng/ml. Participants with low, medium, and high dietary microbe intake represented 35.4, 43.6, and 21.0% of the cohort, respectively. Furthermore, participants were stratified into three groups based on their overall consumption of foods with variable microbe contents. The association between dietary live microbe intake and serum cotinine levels remained robust across all models, with medium intake as the reference (Model 2: ß = -0.14, 95% CI: -0.20, -0.07; High: ß = -0.31, 95% CI: -0.39, -0.22). Moreover, both prebiotic and probiotic use exhibited an inverse relationship with serum cotinine levels (Prebiotic: ß = -0.19, 95% CI: -0.37, -0.01; Probiotic: ß = -0.47, 95% CI: -0.64, -0.30). Subgroup analyses revealed no discernible interactions between dietary live microbe, prebiotic, probiotic use, and serum cotinine levels. Conclusion: Our findings suggest a negative correlation between dietary live microbe intake, as well as non-dietary prebiotic/probiotic consumption, and serum cotinine levels.

The microbial revolution: Unveiling the benefits of vaginal probiotics and prebiotics.

Vaginal health is essential to a woman's overall well-being, as abnormalities in vaginal health can lead to a variety of gynaecological disorders, such as urinary tract infections, yeast infections, and bacterial vaginosis. The vaginal microbiome is essential for the prevention of these infections. Disruptions in this microbial ecosystem can significantly impact vaginal health. The concept of utilizing probiotics and prebiotics to stimulate the growth of protective vaginal microbiota has gathered substantial interest in recent years. Probiotics are live micro-organisms that strengthen and restore vaginal microbial balance by lowering pH levels, production of bacteriocins, biofilm disruption, modulation of immune response, and production of hydrogen peroxide (H2O2), consequently combating the development of pathogens. Prebiotics are oligosaccharides that encourage the development of probiotics such as lactobacilli species. Probiotics and prebiotics also have some broader implications for vaginal health, including their role in minimizing the incidence of premature birth, optimizing fertility, managing menopausal symptoms, and preventing vaginal infections. Synbiotics are a combination of probiotics and prebiotics that deliver additional benefits by encouraging the development and activity of beneficial microbes. Furthermore, postbiotics are bioactive compounds derived from probiotic bacteria during fermentation that have immunomodulatory actions and provide an additional layer of protection against vaginal infections. The present study highlights the most prevalent vaginal infections and limitations of existing therapies that influence the vaginal microbiota. The profound consequences of probiotics and prebiotics in women's health, including their role in minimizing the prevalence of vaginal infections and promoting overall vaginal health, as well as advanced therapeutic strategies such as synbiotics and postbiotics, are also discussed. The literature offers significant insights into the mechanism, efficacy, and safety of probiotics and prebiotics to healthcare providers and researchers.

A Prebiotic Pathway to Nicotinamide Adenine Dinucleotide.

Enzymes play a fundamental role in cellular metabolism. A wide range of enzymes require the presence of complementary coenzymes and cofactors to function properly. While coenzymes are believed to have been part of the last universal ancestor (LUCA) or have been present even earlier, the syntheses of crucial coenzymes like the redox-active coenzymes flavin adenine dinucleotide (FAD) or nicotinamide adenine dinucleotide (NAD+) remain challenging. Here, we present a pathway to NAD+ under prebiotic conditions starting with ammonia, cyanoacetaldehyde, prop-2-ynal and sugar-forming precursors, yielding in situ the nicotinamide riboside. Regioselective phosphorylation and water stable light activated adenosine monophosphate derivatives allow for topographically and irradiation-controlled formation of NAD+. Our findings indicate that NAD+, a coenzyme vital to life, can be formed non-enzymatically from simple organic feedstock molecules via photocatalytic activation under prebiotically plausible early Earth conditions in a continuous process under aqueous conditions.

Prebiotic Treatment in Patients with Nonalcoholic Fatty Liver Disease (NAFLD)-A Randomized Pilot Trial.

Several studies show that gut microbiotas in patients with nonalcoholic fatty liver disease (NAFLD) differ from those in a healthy population, suggesting that this alteration plays a role in NAFLD pathogenesis. We investigated whether prebiotic administration affects liver fat content and/or liver-related and metabolic parameters. Patients with NAFLD and metabolic syndrome (age: 50 ± 11; 79% men) were randomized to receive either 16 g/day of prebiotic (ITFs-inulin-type fructans) (n = 8) or placebo (maltodextrin) (n = 11) for 12 weeks. Patients were instructed to maintain a stable weight throughout the study. Liver fat content (measured by H1MRS), fecal microbiota, and metabolic, inflammatory, and liver parameters were determined before and after intervention. Fecal samples from patients who received the prebiotic had an increased content of Bifidobacterium (p = 0.025), which was not observed with the placebo. However, the baseline and end-of-study liver fat contents did not change significantly in the prebiotic and placebo groups, neither did the liver function tests' metabolic and inflammatory mediators, including fibroblast growth factor-19 and lipopolysaccharide-binding protein. Body weight remained stable in both groups. These findings suggest that prebiotic treatment without weight reduction is insufficient to improve NAFLD.