Gut microbiota of healthy elderly NSAID users is selectively modified with the administration of Lactobacillus acidophilus NCFM and lactitol

Evidence of the Beneficial Impact of Three Probiotic-Based Food Supplements on the Composition and Metabolic Activity of the Intestinal Microbiota in Healthy Individuals: An Ex Vivo Study

Scientific evidence has increasingly supported the beneficial effects of probiotic-based food supplements on human intestinal health. This ex vivo study investigated the effects on the composition and metabolic activity of the intestinal microbiota of three probiotic-based food supplements, containing, respectively, (1) Bifidobacterium longum ES1, (2) Lactobacillus acidophilus NCFM®, and (3) a combination of L. acidophilus NCFM®, Lactobacillus paracasei Lpc-37™, Bifidobacterium lactis Bi-07™, and Bifidobacterium lactis Bl-04™. This study employed fecal samples from six healthy donors, inoculated in a Colon-on-a-plate® system. After 48 h of exposure or non-exposure to the food supplements, the effects were measured on the overall microbial fermentation (pH), changes in microbial metabolic activity through the production of short-chain and branched-chain fatty acids (SCFAs and BCFAs), ammonium, lactate, and microbial composition. The strongest effect on the fermentation process was observed for the combined formulation probiotics, characterized by the significant stimulation of butyrate production, a significant reduction in BCFAs and ammonium in all donors, and a significant stimulatory effect on bifidobacteria and lactobacilli growth. Our findings suggest that the combined formulation probiotics significantly impact the intestinal microbiome of the healthy individuals, showing changes in metabolic activity and microbial abundance as the health benefit endpoint.

The role of the microbiota-gut-brain axis in long-term neurodegenerative processes following traumatic brain injury

Traumatic brain injury (TBI) can be a devastating and debilitating disease to endure. Due to improvements in clinical practice, declining mortality rates have led to research into the long-term consequences of TBI. For example, the incidence and severity of TBI have been associated with an increased susceptibility of developing neurodegenerative disorders, such as Parkinson's or Alzheimer's disease. However, the mechanisms linking this alarming association are yet to be fully understood. Recently, there has been a groundswell of evidence implicating the microbiota-gut-brain axis in the pathogenesis of these diseases. Interestingly, survivors of TBI often report gastrointestinal complaints and animal studies have demonstrated gastrointestinal dysfunction and dysbiosis following injury. Autonomic dysregulation and chronic inflammation appear to be the main driver of these pathologies. Consequently, this review will explore the potential role of the microbiota-gut-brain axis in the development of neurodegenerative diseases following TBI.

Beneficial Effects of Lactic Acid Bacteria on Animal Reproduction Function

Considering the importance of a healthy uterus to the success of breeding, the beneficial effects of lactic acid bacteria on animal reproduction function are of particular interest. In recent decades, infertility has become a widespread issue, with microbiological variables playing a significant role. According to reports, dysbiosis of the vaginal microbiota is connected with infertility; however, the effect of the normal vaginal microbiota on infertility is unknown. In addition, lactic acid bacteria dominate the reproductive system. According to evidence, vaginal lactic acid bacteria play a crucial role in limiting the invasion of pathogenic bacteria by triggering anti-inflammatory chemicals through IL-8, IL-1, and IL-6; immunological responses through inhibition of the adherence of other microorganisms, production of inhibiting substances, and stimulation of mucus production; and also reproductive hormones by increased testosterone hormone release, enhanced the levels of luteinizing hormone, follicle stimulating hormone, the amount of prostaglandin E (2), and prostaglandin F2 alpha. The objective of this study was to compare the advantages of lactic acid bacteria in animal reproduction based on the most recent literature. The administration of a single strain or numerous strains of lactic acid bacteria has a favourable impact on steroidogenesis, gametogenesis, and animal fertility.

Current in Vitro and Animal Models for Understanding Foods: Human Gut-Microbiota Interactions

The food-gut microbiota interaction is an important regulator of human health. Numerous in vitro and animal models have thus been developed in order to simulate the specific food-gut microbiota and/or host-gut microbiota interactions in the human colon. This review summarizes the design principles of each model and discusses their advantages and weaknesses in terms of studying food-gut microbiota interactions. In vitro fermentation models appear to be reliable methods to investigate various aspects involved in the food-gut microbiota interactions in humans. However, many physiological perspectives lack appreciation of these models, such as peristaltic movement, biochemical conditions, and gastrointestinal anatomy. Animal models provide more physiological relevance to human trials compared to in vitro models. However, they may have gastrointestinal tract aspects that are distinct from human subjects. This review contains important information that can help the development of more advanced models to study food-gut microbiota interactions in humans.

Age-Related NAFLD: The Use of Probiotics as a Supportive Therapeutic Intervention

Human aging, a natural process characterized by structural and physiological changes, leads to alterations of homeostatic mechanisms, decline of biological functions, and subsequently, the organism becomes vulnerable to external stress or damage. In fact, the elderly population is prone to develop diseases due to deterioration of physiological and biological systems. With aging, the production of reactive oxygen species (ROS) increases, and this causes lipid, protein, and DNA damage, leading to cellular dysfunction and altered cellular processes. Indeed, oxidative stress plays a key role in the pathogenesis of several chronic disorders, including hepatic diseases, such as non-alcoholic fatty liver disease (NAFLD). NAFLD, the most common liver disorder in the Western world, is characterized by intrahepatic lipid accumulation; is highly prevalent in the aging population; and is closely associated with obesity, insulin resistance, hypertension, and dyslipidemia. Among the risk factors involved in the pathogenesis of NAFLD, the dysbiotic gut microbiota plays an essential role, leading to low-grade chronic inflammation, oxidative stress, and production of various toxic metabolites. The intestinal microbiota is a dynamic ecosystem of microbes involved in the maintenance of physiological homeostasis; the alteration of its composition and function, during aging, is implicated in different liver diseases. Therefore, gut microbiota restoration might be a complementary approach for treating NAFLD. The administration of probiotics, which can relieve oxidative stress and elicit several anti-aging properties, could be a strategy to modify the composition and restore a healthy gut microbiota. Indeed, probiotics could represent a valid supplement to prevent and/or help treating some diseases, such as NAFLD, thus improving the already available pharmacological intervention. Moreover, in aging, intervention of prebiotics and fecal microbiota transplantation, as well as probiotics, will provide novel therapeutic approaches. However, the relevant research is limited, and several scientific research works need to be done in the near future to confirm their efficacy.

The gut microbiome as a modulator of healthy ageing

The gut microbiome is a contributory factor in ageing-related health loss and in several non-communicable diseases in all age groups. Some age-linked and disease-linked compositional and functional changes overlap, while others are distinct. In this Review, we explore targeted studies of the gut microbiome of older individuals and general cohort studies across geographically distinct populations. We also address the promise of the targeted restoration of microorganisms associated with healthier ageing.

Food Additives Associated with Gut Microbiota Alterations in Inflammatory Bowel Disease: Friends or Enemies?

During the 21st century, the incidence and prevalence of inflammatory bowel disease (IBD) is rising globally. Despite the pathogenesis of IBD remaining largely unclear, the interactions between environmental exposure, host genetics and immune response contribute to the occurrence and development of this disease. Growing evidence implicates that food additives might be closely related to IBD, but the involved molecular mechanisms are still poorly understood. Food additives may be categorized as distinct types in accordance with their function and property, including artificial sweeteners, preservatives, food colorant, emulsifiers, stabilizers, thickeners and so on. Various kinds of food additives play a role in modifying the interaction between gut microbiota and intestinal inflammation. Therefore, this review comprehensively synthesizes the current evidence on the interplay between different food additives and gut microbiome alterations, and further elucidates the potential mechanisms of food additives–associated microbiota changes involved in IBD.

Acute and short-term effects of Lactobacillus paracasei subsp. paracasei 431 and inulin intake on appetite control and dietary intake: A two-phases randomized, double blind, placebo-controlled study

This study aims to examine the acute and short-term effects of prebiotics, probiotics, and their combination on appetite, energy intake and satiety related hormones in two phases. The first phase was a randomized, double blind, placebo controlled crossover study. Prebiotic (16 g inulin), probiotic (Lactobacillus paracasei subsp. paracasei 431 (L. casei 431) (>10⁶ cfu/ml), synbiotic (their combination) and control (16 g maltodextrin) dairy drinks were consumed by 16 healthy men with a standard breakfast on four separate test days, and the following satiety responses and ad libitum food intake at lunch and over 24 h were assessed. In the second phase, the effects of 21 days of synbiotic (n = 10) or control (n = 11) drink consumption on appetite sensation, energy intake, serum glucose, insulin, peptide YY, ghrelin, obestatin and adiponectin concentration were assessed in a randomized double-blind placebo-controlled design. In the first phase, energy intake values during ad libitum lunch were the lowest in the prebiotic drink, followed by probiotic, synbiotic and control drinks, respectively (p = 0.017); also the rest of the day and 24-h dietary energy intake was lower by prebiotic and probiotic drinks compared to the control drink (p < 0.05 for each). For short-term effects, no significant difference in anthropometric measurements, hunger-satiety scores and serum glucose, insulin, PYY, ghrelin, obestatin and adiponectin concentrations were recorded. Despite the potential of prebiotics and probiotics to reduce energy intake, further studies are required for a better understanding of their role in satiety related mechanisms.

Effects of phenylbutazone alone or in combination with a nutritional therapeutic on gastric ulcers, intestinal permeability, and fecal microbiota in horses

Background

Gastrointestinal (GI) injury and dysbiosis are adverse events associated with nonsteroidal anti‐inflammatory drug (NSAID) use in horses. Phenylbutazone has been shown to alter GI barrier function both in vitro and ex vivo, but its effects on barrier function have not been assessed in vivo. In addition, the ability of nutritional therapeutics to prevent these changes is not known.

Objective

Our objectives were to determine whether (a) phenylbutazone affected barrier function in vivo and (b) if phenylbutazone‐induced GI injury could be ameliorated by the use of a nutritional therapeutic.

Animals

Thirty healthy horses were randomly assigned to 3 groups (n = 10 per group): control, phenylbutazone, or phenylbutazone plus nutritional therapeutic.

Methods

This study was conducted as a blinded, randomized block design. All horses were managed identically throughout the study period. Samples were collected throughout the study period to monitor fecal microbiota changes and gastric ulcers before and after treatment. Quantification of the bacterial 16S rRNA gene in blood was used as a marker of intestinal permeability.

Results

Phenylbutazone increased amounts of bacterial 16S rDNA in circulation 3.02‐fold (95% confidence interval [CI], 0.1.89‐4.17), increased gastric ulceration score by a mean of 1.1 grade (P = .02), and induced specific changes in the microbiota, including loss of Pseudobutyrivibrio of family Lachnospiraceae. These changes were attenuated by nutritional treatment.

Conclusions and Clinical Importance

Collectively, these findings suggest that phenylbutazone induces GI injury, including impaired barrier function, and that nutritional treatment could attenuate these changes.

Role of Probiotics, Prebiotics, and Synbiotics in the Elderly: Insights Into Their Applications

Elderly people are an important part of the global population who suffer from the natural processes of senescence, which lead to changes in the gut microbiota composition. These modifications have a great impact on their quality of life, bringing a general putrefactive and inflammatory status as a consequence. Some of the most frequent conditions related to this status are constipation, undernutrition, neurodegenerative diseases, susceptibility to opportunistic pathogens, and metabolic disbalance, among others. For these reasons, there is an increasing interest in improving their quality of life by non-invasive treatments such as the consumption of probiotics, prebiotics, and synbiotics. The aim of the present mini-review is to describe the benefits of these functional supplements/food according to the most recent clinical and pre-clinical studies published during the last decade. In addition, insights into several aspects we consider relevant to improve the quality of future studies are provided.

The Gut Microbiome, Aging, and Longevity: A Systematic Review

Aging is determined by complex interactions among genetic and environmental factors. Increasing evidence suggests that the gut microbiome lies at the core of many age-associated changes, including immune system dysregulation and susceptibility to diseases. The gut microbiota undergoes extensive changes across the lifespan, and age-related processes may influence the gut microbiota and its related metabolic alterations. The aim of this systematic review was to summarize the current literature on aging-associated alterations in diversity, composition, and functional features of the gut microbiota. We identified 27 empirical human studies of normal and successful aging suitable for inclusion. Alpha diversity of microbial taxa, functional pathways, and metabolites was higher in older adults, particularly among the oldest-old adults, compared to younger individuals. Beta diversity distances significantly differed across various developmental stages and were different even between oldest-old and younger-old adults. Differences in taxonomic composition and functional potential varied across studies, but Akkermansia was most consistently reported to be relatively more abundant with aging, whereas Faecalibacterium, Bacteroidaceae, and Lachnospiraceae were relatively reduced. Older adults have reduced pathways related to carbohydrate metabolism and amino acid synthesis; however, oldest-old adults exhibited functional differences that distinguished their microbiota from that of young-old adults, such as greater potential for short-chain fatty acid production and increased butyrate derivatives. Although a definitive interpretation is limited by the cross-sectional design of published reports, we integrated findings of microbial composition and downstream functional pathways and metabolites, offering possible explanations regarding age-related processes.

Gut microbiota and old age: Modulating factors and interventions for healthy longevity

Our gut microbiota is a complex and dynamic ecosystem with a paramount role in shaping our metabolic and immunological functions. Recent research suggests that aging may negatively affect the composition, diversity, and function of our microbiota mainly due to alterations in diet and immunologic reactivity (i.e. immunosenescence), and increased incidence of certain diseases and, therefore, increased exposure to certain medication (e.g. antibiotics, proton pump inhibitors). In turn, this aging-related gut dysbiosis may contribute to the initiation and/or progress of other metabolic diseases, and consequently, to a decrease in healthy longevity. On the positive side, promising therapeutic interventions, such as diet supplementation with prebiotics, probiotics and synbiotics, or fecal microbiota transplantation, aimed to counteract these aging-related deleterious consequences, could improve our health, and extend our healthy lifespan. In this context, the current review aims to assess the latest progress in identifying the key elements affecting the gut microbiota of the older adults and their mechanism of action, and the effectiveness of the therapeutic interventions aimed at restoring the diversity and healthy functions of the gut microbiota in older individuals.

Association between Altered Blood Parameters and Gut Microbiota after Synbiotic Intake in Healthy, Elderly Korean Women

Synbiotics intake can alter the composition of intestinal microbes beneficially. We aimed to detect the changes in the intestinal microbiomes of 37 healthy elderly Korean women after the intake of a synbiotic drink. This was a longitudinal study controlled with a temporal series, including a control period of 3 weeks before intake, synbiotic intake for 3 weeks, and a washout period of 3 weeks. Fecal microbiota composition was analyzed by sequencing the V3-V4 hypervariable regions of 16S rRNA. Physical fecal activity increased with improvement in fecal shape. Thirty intestinal bacterial taxa were observed to change only after the intake period. In particular, Ellagibacter appeared only after ingestion. In addition, the abundance of Terrisporobacter showed a positive correlation with C-reactive protein, triglyceride. Lachnospiraceae_uc, Eubacterium_g5, and Blautia had a positive correlation with creatinine, whereas PAC001100_g had a negative correlation with creatinine. Short-term (3 weeks) intake of symbiotic organisms changes the composition of the gut microbiota in healthy elderly Korean women.

Plausible Biological Interactions of Low- and Non-Calorie Sweeteners with the Intestinal Microbiota: An Update of Recent Studies

Sweeteners that are a hundred thousand times sweeter than sucrose are being consumed as sugar substitutes. The effects of sweeteners on gut microbiota composition have not been completely elucidated yet, and numerous gaps related to the effects of nonnutritive sweeteners (NNS) on health still remain. The NNS aspartame and acesulfame-K do not interact with the colonic microbiota, and, as a result, potentially expected shifts in the gut microbiota are relatively limited, although acesulfame-K intake increases Firmicutes and depletes Akkermansia muciniphila populations. On the other hand, saccharin and sucralose provoke changes in the gut microbiota populations, while no health effects, either positive or negative, have been described; hence, further studies are needed to clarify these observations. Steviol glycosides might directly interact with the intestinal microbiota and need bacteria for their metabolization, thus they could potentially alter the bacterial population. Finally, the effects of polyols, which are sugar alcohols that can reach the colonic microbiota, are not completely understood; polyols have some prebiotics properties, with laxative effects, especially in patients with inflammatory bowel syndrome. In this review, we aimed to update the current evidence about sweeteners' effects on and their plausible biological interactions with the gut microbiota.

Prebiotics metabolism by gut-isolated probiotics

There are numerous species of bacteria resides in the lumen of human colon. The word 'colon', resembles colony or the colonization of microbiota of which plays an important role in the fermentation of prebiotics. The standpoint of prebiotic nowadays is well reported for attenuating gut dysbiosis in many clinical studies tested on animals and human. However, because of the huge amount of gut microbiome, the attempt to connect the dots between bacterial population and the host are not plainly discernible. Thus, a need to analyse recent research on the pathways of prebiotic metabolism adopted by commonly studied probiotics i.e. Bifidobacteria and Lactobacillus. Several different substrate-dependent gene expressions are induced to break down oligosaccharide molecules shown by those probiotics. The hydrolysis can occur either by membrane bound (extracellular) or cytoplasmic (intracellular) enzyme of the enteric bacteria. Therefore, this review narrates several prebiotic metabolisms occur during gut fermentation, and metabolite production i.e. organic acids conversion.

Diet Associated with Inflammation and Alzheimer's Disease

Neurocognitive disorders, such as Alzheimer's disease (AD), affect millions of people worldwide and are characterized by cognitive decline. Human and animal studies have shown that chronic immune response and inflammation are important factors in the pathogenesis of AD. Chronic inflammation can accelerate the aggregation of amyloid-β peptides and later hyperphosphorylation of tau proteins. The exact etiology of AD is not clear, but genetics and environmental factors, such as age, family history, and lifestyle are linked to neurodegenerative diseases. Lifestyle habits, such as poor diet, are associated with inflammation and could accelerate or slow down the progression of neurodegenerative diseases. Here we provide a review of the potential conditions and factors that stimulate the inflammatory processes in AD. An understanding of inflammatory mechanisms influencing the development of AD may help to protect against dementia and AD.

Gut microbiota is associated with adiposity markers and probiotics may impact specific genera

PURPOSE

It has been suggested that restoring gut microbiota alterations with probiotics represents a potential clinical target for the treatment of gut microbiota-related diseases, such as obesity. Here, we apply 16S rDNA microbiota profiling to establish which bacteria in the human gut are associated with obesity and cardiometabolic risk factors, and to evaluate whether probiotic supplementation modulates gut microbiota.

METHODS

We evaluated the effects of a probiotic mixture (2 × 10¹⁰ CFU/day of Lactobacillus acidophilus LA-14, Lactobacillus casei LC-11, Lactococcus lactis LL-23, Bifidobacterium bifidum BB-06, and Bifidobacterium lactis BL-4) in 32 overweight or obese women in a double-blind, randomized, placebo-controlled study. Using 16S rDNA sequencing, we characterized fecal samples and investigated the relationships between microbiome data and diet, body composition, antioxidant enzymes, and inflammatory profile. In addition, we characterized the degree of variation among fecal communities after the intervention.

RESULTS

BMI, weight, fat mass, lean mass, conicity index, protein intake, monounsaturated fat intake, glycated hemoglobin, TNF-α, and IL6/IL10 were significantly correlated with microbiome composition. The candidate division TM7 was strongly associated with all adiposity markers and Clostridiaceae associated negatively with TNF-α. The family Clostridiaceae increased and TM7 tended to decrease after the probiotic mixture supplementation. Subjects were clustered according to body composition, and a higher proportion of TM7 was observed in those with higher adiposity.

CONCLUSIONS

Ecosystem-wide analysis of probiotic use effects on the gut microbiota revealed a genera specific influence, and one of which (TM7) represents a promising novel target for obesity treatment.

TRIAL REGISTRATION NUMBER

U1111-1137-4566.

Effects of Sweeteners on the Gut Microbiota: A Review of Experimental Studies and Clinical Trials

The consumption of sugar-free foods is growing because of their low-calorie content and the health concerns about products with high sugar content. Sweeteners that are frequently several hundred thousand times sweeter than sucrose are being consumed as sugar substitutes. Although nonnutritive sweeteners (NNSs) are considered safe and well tolerated, their effects on glucose intolerance, the activation of sweet taste receptors, and alterations to the composition of the intestinal microbiota are controversial. This review critically discusses the evidence supporting the effects of NNSs, both synthetic sweeteners (acesulfame K, aspartame, cyclamate, saccharin, neotame, advantame, and sucralose) and natural sweeteners (NSs; thaumatin, steviol glucosides, monellin, neohesperidin dihydrochalcone, and glycyrrhizin) and nutritive sweeteners (polyols or sugar alcohols) on the composition of microbiota in the human gut. So far, only saccharin and sucralose (NNSs) and stevia (NS) change the composition of the gut microbiota. By definition, a prebiotic is a nondigestible food ingredient, but some polyols can be absorbed, at least partially, in the small intestine by passive diffusion: however, a number of them, such as isomaltose, maltitol, lactitol, and xylitol, can reach the large bowel and increase the numbers of bifidobacteria in humans. Further research on the effects of sweeteners on the composition of the human gut microbiome is necessary.

Nutrition and the gut microbiome in the elderly

The gut microbiota is the assembly of microorganisms living in our intestine and their genomes are known as the microbiome. The correct composition and functionality of this microbiome is essential for maintaining a "healthy status." Aging is related to changes in the gut microbiota which are frequently associated with physiological modifications of the gastrointestinal tract, as well as, to changes in dietary patterns, together with a concomitant decline in cognitive and immune function, all together contributing to frailty. Therefore, nutritional strategies directed at restoring the microbiota in the elderly have to be addressed from a global perspective, considering not only the microbiota but also other extra-intestinal targets of action. The present review aims at summarizing the current knowledge on intestinal microbiota alterations and other functions impaired in the elderly and to analyze tools for implementing nutritional strategies, through the use of probiotics, prebiotics or specific nutrients in order to counterbalance such alterations.

An In Vitro Approach to Study Effects of Prebiotics and Probiotics on the Faecal Microbiota and Selected Immune Parameters Relevant to the Elderly

The aging process leads to alterations of gut microbiota and modifications to the immune response, such changes may be associated with increased disease risk. Prebiotics and probiotics can modulate microbiome changes induced by aging; however, their effects have not been directly compared. The aim of this study was to use anaerobic batch culture fermenters to assess the impact of various fermentable carbohydrates and microorganisms on the gut microbiota and selected immune markers. Elderly volunteers were used as donors for these experiments to enable relevance to an aging population. The impact of fermentation supernatants on immune markers relevant to the elderly were assessed in vitro. Levels of IL-1β, IL-6, IL-8, IL-10 and TNF-α in peripheral blood mononuclear cell culture supernatants were measured using flow cytometry. Trans-galactooligosaccharides (B-GOS) and inulin both stimulated bifidobacteria compared to other treatments (p<0.05). Fermentation supernatants taken from faecal batch cultures supplemented with B-GOS, inulin, B. bifidum, L. acidophilus and Ba. coagulans inhibited LPS induced TNF-α (p<0.05). IL-10 production, induced by LPS, was enhanced by fermentation supernatants from faecal batch cultures supplemented with B-GOS, inulin, B. bifidum, L. acidophilus, Ba. coagulans and Bac. thetaiotaomicron (p<0.05). To conclude, prebiotics and probiotics could lead to potentially beneficial effects to host health by targeting specific bacterial groups, increasing saccharolytic fermentation and decreasing inflammation associated with aging. Compared to probiotics, prebiotics led to greater microbiota modulation at the genus level within the fermenters.

Independent and Combined Effects of Lactitol, Polydextrose, and Bacteroides thetaiotaomicron on Postprandial Metabolism and Body Weight in Rats Fed a High-Fat Diet

Obesity is related to the consumption of energy-dense foods in addition to changes in the microbiome where a higher abundance of gut Bacteroidetes can be found in lean subjects or after weight loss. Lactitol, a sweet-tasting sugar alcohol, is a common sugar-replacement in foods. Polydextrose (PDX), a highly branched glucose polymer, is known to reduce energy intake. Here, we test if the combined effects of lactitol or PDX in combination with Bacteroides species will have a beneficial metabolic response in rats fed a high-fat (HF) diet. A total of 175 male Wistar rats were fed either a LF or HF diet. Bacteroides thetaiotaomicron (10¹⁰ bacteria/animal/day) was orally administered with or without lactitol (1.6−2 g/animal/day) or PDX (2 g/animal/day) for 8 days. Postprandial blood samples, cecal digesta, and feces were collected on the last day. Measurements included: body weight, feed consumption, cecal short-chain fatty acids, fecal dry matter and heat value, blood glucose, insulin, triglyceride, and satiety hormone concentrations. Lactitol and PDX decreased the mean body weight when administered with B. thetaiotaomicron or when lactitol was administered alone. Levels of postprandial plasma triglycerides declined with lactitol and PDX when administered with B. thetaiotaomicron. For intestinal hormone release, lactitol – alone or with B. thetaiotaomicron – increased the release of gastrointestinal peptide tyrosine tyrosine (PYY) as well as the area under the curve (AUC) measured for PYY (0–8 h). In addition, levels of insulin AUC (0–8 h) decreased in the lactitol and PDX-supplemented groups. Lactitol and PDX may both provide additional means to regulate postprandial metabolism and weight management, whereas the addition of B. thetaiotaomicron in the tested doses had only minor effects on the measured parameters.

The Role of Probiotics on the Microbiota: Effect on Obesity

The microbiota and the human host maintain a symbiotic association. Nowadays, metagenomic analyses are providing valuable knowledge on the diversity and functionality of the gut microbiota. However, with regard to the definition of a "healthy microbiota" and the characterization of the dysbiosis linked to obesity, there is still not a clear answer. Despite this fact, attempts have been made to counteract obesity through probiotic supplementation. A literature search of experimental studies relevant to the topic was performed in PubMed database with the keywords "probiotic" and "obesity" and restricted to those with "Lactobacillus" or "Bifidobacterium" in the title. So far, evidence of an antiobesity effect of different lactobacilli and bifidobacteria has been mainly obtained from animal models of dietary-induced obesity. Using these experimental models, a substantial number of studies have reported reductions in weight gain and, in particular, fat tissue mass at different locations following administration of bacteria, as compared with controls. Antiatherogenic and anti-inflammatory effects-including regulation of expression of lipogenic and lipolytic genes in the liver, reduction in liver steatosis, improvement of blood lipid profile and glucose tolerance, decreased endotoxemia, and regulation of inflammatory pathways-are also reported in many of them. The number of human studies focused on probiotic administration for obesity management is still very scarce, and it is too soon to judge their potential efficacy, especially when considering the fact that the actions of probiotics are always strain specific and the individual response varies according to intrinsic factors, the overall composition of diet, and their interactions.

Lentinula edodes-derived polysaccharide rejuvenates mice in terms of immune responses and gut microbiota

Aging is characterized by impaired immunity and unbalanced gut microbiota. Prebiotics have the capability to prevent or reverse age-related declines in health by modulating gut microbiota. Mushroom polysaccharides have been suggested to be potential prebiotics. However, their effects on the immunity and gut microbiota in aged mice have not been determined. This study firstly assessed the effects of a heteropolysaccharide L2 isolated from the fruit body of L. edodes on the immune response of aged mice, and then compared the composition of fecal microbiota in adult (N), old (O) and L2-treated old (Oa) mice using the high-throughput pyrosequencing technique. The results showed that L2 can restore the age-attenuated immune responses by increasing cytokine levels in peripheral blood. Moreover, L2 can partly reverse the age-altered composition of gut microbiota. The Euclidean distances (De) among 3 groups (N, O and Oa) are determined to be De(O, N) = 0.19, De(O, Oa) = 0.20, and De(N, Oa) = 0.10, i.e. there is a marked reduction in the distance from 0.19 to 0.1 by L2. This suggests the beneficial effects of L2 on enhancing immunity and improving gut health.

The Differential Proteome of the Probiotic Lactobacillus acidophilus NCFM Grown on the Potential Prebiotic Cellobiose Shows Upregulation of Two β -Glycoside Hydrolases

Probiotics, prebiotics, and combinations thereof, that is, synbiotics, are known to exert beneficial health effects in humans; however interactions between pro- and prebiotics remain poorly understood at the molecular level. The present study describes changes in abundance of different proteins of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) when grown on the potential prebiotic cellobiose as compared to glucose. Cytosolic cell extract proteomes after harvest at late exponential phase of NCFM grown on cellobiose or glucose were analyzed by two dimensional difference gel electrophoresis (2D-DIGE) in the acidic (pH 4-7) and the alkaline (pH 6-11) regions showing a total of 136 spots to change in abundance. Proteins were identified by MS or MS/MS from 81 of these spots representing 49 unique proteins and either increasing 1.5-13.9-fold or decreasing 1.5-7.8-fold in relative abundance. Many of these proteins were associated with energy metabolism, including the cellobiose related glycoside hydrolases phospho-β-glucosidase (LBA0881) and phospho-β-galactosidase II (LBA0726). The data provide insight into the utilization of the candidate prebiotic cellobiose by the probiotic bacterium NCFM. Several of the upregulated or downregulated identified proteins associated with utilization of cellobiose indicate the presence of carbon catabolite repression and regulation of enzymes involved in carbohydrate metabolism.

A pilot study on the effect of Lactobacillus casei Zhang on intestinal microbiota parameters in Chinese subjects of different age

Ageing of the population is an imminent global problem. Lactobacillus casei Zhang (LcZ) was isolated from Inner Mongolian fermented milk, koumiss. LcZ possesses numerous probiotic properties in in vitro tests and in animal models. However, it has never been tested in any human trial. In the current study, the impact of oral consumption of LcZ on different age groups was tested. Chinese subjects, including 10 young, 7 middle-aged and 7 elderly volunteers (with mean age of 24.3, 47.6 and 64.7, respectively), were recruited. Each subject took 10.6 log10 cfu LcZ daily for a continuous period of 28 days. Several parameters, including the amounts of LcZ and four selected groups of bacteria, change of bacterial diversity, short chain fatty acids (SCFA) and total bile acids (TBA), were monitored in faecal samples collected from the subjects before starting, during and after stopping oral LcZ consumption. The consumption of LcZ exhibited beneficial effects to the subjects by modulating faecal microbiota in a temporal manner with a prolonged elevation of SCFA and reduction of TBA. The potentially harmful Pseudomonas and Acinetobacter genera were suppressed by the probiotic administration. Furthermore, a moderately divergent response was observed in the indigenous gut populations of Bifidobacterium and Bacteroides fragilis group in different age subjects. Taken together, the current study has provided proof on the positive effect of probiotic consumption and crucial insights into the design and application of probiotic-based products to users of different age segments.

Review on microbiota and effectiveness of probiotics use in older

The aim of the present systematic review is to summarize the existing knowledge about the human microbiota in the elderly and the effects of probiotics in elderly population. The elderly subjects, compared to adult population, show a reduction in the diversity of the microbiota, characterized by a large interindividual variability, with lower numbers of Firmicutes, Bifidobacteria, Clostridium cluster XIV, Faecalibacterium Prausnitzii, Blautia coccoides-Eubacterium rectal and higher presence of Enterobacteriaceae and Bacteroidetes. These differences of the intestinal microbiota of the elderly may not necessarily be caused by aging, but they could be associated with the decline of the general state of health with malnutrition and with increased need for medication, such as antibiotics and nonsteroidal anti-inflammatory drugs, situations that occur frequently in the elderly. Differences have been demonstrated in the composition of the microbiota between healthy elderly subjects and hospitalized or institutionalized elderly subjects. These findings which further indicates that the living conditions, health status, nutrition and drugs have a significant effect on the composition of the microbiota. According to the available knowledge, the use of probiotics is safe and could represent an useful intervention to prevent or treat antibiotic-associated diarrhea, in addition to reducing the severity of symptoms, other than to help the management of constipation.

Impaired responses to gliadin and gut microbes of immune cells from mice with altered stress-related behavior and premature immune senescence

Stress is associated with impaired communication between the nervous and immune systems leading to immunosenescence and increased disease risk. We investigated whether leukocytes from mice with altered stress-related behavior and premature immunosenescence, as well as from chronologically aged mice differently responded ex vivo to celiac disease (CD) triggers (gliadin) and intestinal bacteria by ELISA and flow cytometry and differed in microbiota composition. We found that altered stress-related behavior and premature immunosenescence led to alterations in T lymphocytes and cytokine release of immune cells basally and in response to peptic fragments of gliadin and commensal and pathogenic bacteria, possibly increasing susceptibility to CD in adulthood.

Compositional dynamics of the human intestinal microbiota with aging: implications for health

The human gut contains trillions of microbes which form an essential part of the complex ecosystem of the host. This microbiota is relatively stable throughout adult life, but may fluctuate over time with aging and disease. The gut microbiota serves a number of functions including roles in energy provision, nutrition and also in the maintenance of host health such as protection against pathogens. This review summarizes the age-related changes in the microbiota of the gastrointestinal tract (GIT) and the link between the gut microbiota in health and disease. Understanding the composition and function of the gut microbiota along with the changes it undergoes overtime should aid the design of novel therapeutic strategies to counteract such alterations. These strategies include probiotic and prebiotic preparations as well as targeted nutrients, designed to enrich the gut microbiota of the aging population.

Compositional dynamics of the human intestinal microbiota with aging: implications for health

The human gut contains trillions of microbes which form an essential part of the complex ecosystem of the host. This microbiota is relatively stable throughout adult life, but may fluctuate over time with aging and disease. The gut microbiota serves a number of functions including roles in energy provision, nutrition and also in the maintenance of host health such as protection against pathogens. This review summarizes the age-related changes in the microbiota of the gastrointestinal tract (GIT) and the link between the gut microbiota in health and disease. Understanding the composition and function of the gut microbiota along with the changes it undergoes overtime should aid the design of novel therapeutic strategies to counteract such alterations. These strategies include probiotic and prebiotic preparations as well as targeted nutrients, designed to enrich the gut microbiota of the aging population.

Synbiotic Lactobacillus acidophilus NCFM and cellobiose does not affect human gut bacterial diversity but increases abundance of lactobacilli, bifidobacteria and branched-chain fatty acids: a randomized, double-blinded cross-over trial

Probiotics, prebiotics, and combinations thereof, that is synbiotics, have been reported to modulate gut microbiota of humans. In this study, effects of a novel synbiotic on the composition and metabolic activity of human gut microbiota were investigated. Healthy volunteers (n = 18) were enrolled in a double-blinded, randomized, and placebo-controlled cross-over study and received synbiotic [Lactobacillus acidophilus NCFM (10(9) CFU) and cellobiose (5 g)] or placebo daily for 3 weeks. Fecal samples were collected and lactobacilli numbers were quantified by qPCR. Furthermore, 454 tag-encoded amplicon pyrosequencing was used to monitor the effect of synbiotic on the composition of the microbiota. The synbiotic increased levels of Lactobacillus spp. and relative abundances of the genera Bifidobacterium, Collinsella, and Eubacterium while the genus Dialister was decreased (P < 0.05). No other effects were found on microbiota composition. Remarkably, however, the synbiotic increased concentrations of branched-chain fatty acids, measured by gas chromatography, while short-chain fatty acids were not affected.

Effect of yogurt containing polydextrose, Lactobacillus acidophilus NCFM and Bifidobacterium lactis HN019: a randomized, double-blind, controlled study in chronic constipation

Background

Constipation is a frequent complaint and the combination of a prebiotic and probiotics could have a potentially synergic effect on the intestinal transit. The present study therefore aims to investigate the combination of polydextrose (Litesse®), L. acidophilus NCFM® and B. lactis HN019 in a yogurt on intestinal transit in subjects who suffer from constipation.

Methods

Patients with constipation were randomly divided into two groups, Control Group (CG) and Treatment Group (TG), and had to eat 180 ml of unflavored yogurt every morning for 14 days. Those in the CG received only yogurt, while the TG received yogurt containing polydextrose, L. acidophilus NCFM® (ATCC 700396) and B. lactis HN019 (AGAL NM97/09513).

Results

Favourable clinical response was assessed since Agachan score had a significant reduction at the end of the study in both groups and tended to be better in the TG. The subjects in the treatment group also had a shorter transit time at the end of the intervention compared to the control group (p = 0.01).

Conclusion

The product containing yogurt with polydextrose, B. lactis HN019 and L. acidophilus NCFM® significantly shortened colonic transit time after two weeks in the TG compared to CG and may be an option for treatment of constipation.

Chronic functional bowel syndrome enhances gut-brain axis dysfunction, neuroinflammation, cognitive impairment, and vulnerability to dementia

The irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder world wide that lasts for decades. The human gut harbors a diverse population of microbial organisms which is symbiotic and important for well being. However, studies on conventional, germ-free, and obese animals have shown that alteration in normal commensal gut microbiota and an increase in pathogenic microbiota-termed "dysbiosis", impact gut function, homeostasis, and health. Diarrhea, constipation, visceral hypersensitivity, and abdominal pain arise in IBS from the gut-induced dysfunctional metabolic, immune, and neuro-immune communication. Dysbiosis in IBS is associated with gut inflammation. Gut-related inflammation is pivotal in promoting endotoxemia, systemic inflammation, and neuroinflammation. A significant proportion of IBS patients chronically consume alcohol, non-steroidal anti-inflammatories, and fatty diet; they may also suffer from co-morbid respiratory, neuromuscular, psychological, sleep, and neurological disorders. The above pathophysiological substrate is underpinned by dysbiosis, and dysfunctional bidirectional "Gut-Brain Axis" pathways. Pathogenic gut microbiota-related systemic inflammation (due to increased lipopolysaccharide and pro-inflammatory cytokines, and barrier dysfunction), may trigger neuroinflammation enhancing dysfunctional brain regions including hippocampus and cerebellum. These as well as dysfunctional vago-vagal gut-brain axis may promote cognitive impairment. Indeed, inflammation is characteristic of a broad spectrum of neurodegenerative diseases that manifest demntia. It is argued that an awareness of pathophysiological impact of IBS and implementation of appropriate therapeutic measures may prevent cognitive impairment and minimize vulnerability to dementia.

Complete Genome Sequence of Probiotic Strain Lactobacillus acidophilus La-14

We present the 1,991,830-bp complete genome sequence of Lactobacillus acidophilus strain La-14 (SD-5212). Comparative genomic analysis revealed 99.98% similarity overall to the L. acidophilus NCFM genome. Globally, 111 single nucleotide polymorphisms (SNPs) (95 SNPs, 16 indels) were observed throughout the genome. Also, a 416-bp deletion in the LA14_1146 sugar ABC transporter was identified.

Ageing and gut microbes: perspectives for health maintenance and longevity

The ageing process affects the human gut microbiota phylogenetic composition and its interaction with the immune system. Age-related gut microbiota modifications are associated with immunosenescence and inflamm-ageing in a sort of self-sustaining loop, which allows the placement of gut microbiota unbalances among both the causes and the effects of the inflamm-ageing process. Even if, up to now, the link between gut microbiota and the ageing process is only partially understood, the gut ecosystem shows the potential to become a promising target for strategies able to contribute to the health status of older people. In this context, the consumption of pro/prebiotics may be useful in both prevention and treatment of age-related pathophysiological conditions, such as recovery and promotion of immune functions, i.e. adjuvant effect for influenza vaccine, and prevention and/or alleviation of common "winter diseases", as well as constipation and Clostridium difficile-associated diarrhoea. Moreover, being involved in different mechanisms which concur in counteracting inflammation, such as down-regulation of inflammation-associated genes and improvement of colonic mucosa conditions, probiotics have the potentiality to be involved in the promotion of longevity.

A probiotics-containing biscuit modulates the intestinal microbiota in the elderly

OBJECTIVES

Evaluation of the impact of a biscuit containing the probiotics Bifidobacterium longum Bar33 and Lactobacillus helveticus Bar13 on the intestinal microbiota in the elderly.

DESIGN

Randomized double-blind placebo-controlled trial.

PARTICIPANTS

Thirty-two elderly volunteers living in Italy. The group was composed of 19 women and 13 men aged between 71 and 88 years (mean 76).

INTERVENTION

Subjects were randomized in two groups consuming one dose of the probiotics-containing biscuit or placebo once a day for 30 days.

MEASUREMENTS

For each subject the intestinal microbiota was characterized using the phylogenetic microarray platform HTF-Microbi.Array before and after intervention.

RESULTS

Our data demonstrated that one-month consumption of a probiotics-containing biscuit was effective in redressing some of the age-related dysbioses of the intestinal microbiota. In particular, the probiotic treatment reverted the age-related increase of the opportunistic pathogens Clostridium cluster XI, Clostridium difficile, Clostridium perfringens, Enterococcus faecium and the enteropathogenic genus Campylobacter.

CONCLUSION

The present study opens the way to the development of elderly-tailored probiotic-based functional foods to counteract the age-related dysbioses of the intestinal microbiota.

The effect of selected synbiotics on microbial composition and short-chain fatty acid production in a model system of the human colon

BACKGROUND

Prebiotics, probiotics and synbiotics can be used to modulate both the composition and activity of the gut microbiota and thereby potentially affecting host health beneficially. The aim of this study was to investigate the effects of eight synbiotic combinations on the composition and activity of human fecal microbiota using a four-stage semicontinuous model system of the human colon.

METHODS AND FINDINGS

Carbohydrates were selected by their ability to enhance growth of the probiotic bacteria Lactobacillus acidophilus NCFM (NCFM) and Bifidobacterium animalis subsp. lactis Bl-04 (Bl-04) under laboratory conditions. The most effective carbohydrates for each probiotic were further investigated, using the colonic model, for the ability to support growth of the probiotic bacteria, influence the composition of the microbiota and stimulate formation of short-chain fatty acids (SCFA).The following combinations were studied: NCFM with isomaltulose, cellobiose, raffinose and an oat β-glucan hydrolysate (OBGH) and Bl-04 with melibiose, xylobiose, raffinose and maltotriose. All carbohydrates showed capable of increasing levels of NCFM and Bl-04 during fermentations in the colonic model by 10(3)-10(4) fold and 10-10(2) fold, respectively. Also the synbiotic combinations decreased the modified ratio of Bacteroidetes/Firmicutes (calculated using qPCR results for Bacteroides-Prevotella-Porphyromonas group, Clostridium perfringens cluster I, Clostridium coccoides - Eubacterium rectale group and Clostridial cluster XIV) as well as significantly increasing SCFA levels, especially acetic and butyric acid, by three to eight fold, as compared to the controls. The decreases in the modified ratio of Bacteroidetes/Firmicutes were found to be correlated to increases in acetic and butyric acid (p=0.04 and p=0.03, respectively).

CONCLUSIONS

The results of this study show that all synbiotic combinations investigated are able to shift the predominant bacteria and the production of SCFA of fecal microbiota in a model system of the human colon, thereby potentially being able to manipulate the microbiota in a way connected to human health.

Transcriptional analysis of prebiotic uptake and catabolism by Lactobacillus acidophilus NCFM

The human gastrointestinal tract can be positively modulated by dietary supplementation of probiotic bacteria in combination with prebiotic carbohydrates. Here differential transcriptomics and functional genomics were used to identify genes in Lactobacillus acidophilus NCFM involved in the uptake and catabolism of 11 potential prebiotic compounds consisting of α- and β- linked galactosides and glucosides. These oligosaccharides induced genes encoding phosphoenolpyruvate-dependent sugar phosphotransferase systems (PTS), galactoside pentose hexuronide (GPH) permease, and ATP-binding cassette (ABC) transporters. PTS systems were upregulated primarily by di- and tri-saccharides such as cellobiose, isomaltose, isomaltulose, panose and gentiobiose, while ABC transporters were upregulated by raffinose, Polydextrose, and stachyose. A single GPH transporter was induced by lactitol and galactooligosaccharides (GOS). The various transporters were associated with a number of glycoside hydrolases from families 1, 2, 4, 13, 32, 36, 42, and 65, involved in the catabolism of various α- and β-linked glucosides and galactosides. Further subfamily specialization was also observed for different PTS-associated GH1 6-phospho-β-glucosidases implicated in the catabolism of gentiobiose and cellobiose. These findings highlight the broad oligosaccharide metabolic repertoire of L. acidophilus NCFM and establish a platform for selection and screening of both probiotic bacteria and prebiotic compounds that may positively influence the gastrointestinal microbiota.

Bifidobacterium animalis ssp. lactis 420 Protects against Indomethacin-Induced Gastric Permeability in Rats

Gastrointestinal (GI) adverse effects such as erosion and increased permeability are common during the use of nonsteroidal anti-inflammatory drugs (NSAIDs). Our objective was to assess whether Bifidobacterium animalis ssp. lactis 420 protects against NSAID-induced GI side effects in a rat model. A total of 120 male Wistar rats were allocated into groups designated as control, NSAID, and probiotic. The NSAID and probiotic groups were challenged with indomethacin (10 mg/kg(-1); single dose). The probiotic group was also supplemented daily with 10(10) CFU of B. lactis 420 for seven days prior to the indomethacin administration. The control group rats received no indomethacin or probiotic. The permeability of the rat intestine was analysed using carbohydrate probes and the visual damage of the rat stomach mucosa was graded according to severity. B. lactis 420 significantly reduced the indomethacin-induced increase in stomach permeability. However, the protective effect on the visual mucosal damage was not significant. The incidence of severe NSAID-induced lesions was, nevertheless, reduced from 50% to 33% with the probiotic treatment. To conclude, the B. lactis 420 supplementation protected the rats from an NSAID-induced increase in stomach permeability and may reduce the formation of more serious GI mucosal damage and/or enhance the recovery rate of the stomach mucosa.

Probiotics and Immune Response to Exercise

Probiotics are live microorganisms present in several foods and nutritional supplements that may prevent or limit the effects of various illnesses and infections and elicit a range of health benefits in physically active individuals. The primary clinical areas of interest with probiotics include metabolism; gastrointestinal, inflammatory, and functional disorders; the respiratory system; and a range of infections and allergies. The gastrointestinal tract is a key element controlling and regulating adaptation to exercise and physical activity. Gut symptomatology such as nausea, bloating, cramping, pain, diarrhea, and bleeding occurs in some highly active individuals such as athletes, particularly in prolonged exhaustive events. A small number of studies examining probiotic supplementation in highly active individuals indicate modest clinical benefits in terms of reduced frequency, severity, and/or duration of respiratory and gastrointestinal illness. The purported mechanisms of action for probiotics include direct interaction with the gut microbiota, interaction with the gut epithelium and mucosal immune system, and via immune signaling to organs and systems including the liver, brain, and respiratory tract. Future research will identify additional biologically and clinically beneficial strains, validate multicomponent formulations, clarify dose–response issues, and inform the development of guidelines for clinicians, health care practitioners, and the general community.