Antiobesity effects of Bifidobacterium breve strain B-3 supplementation in a mouse model with high-fat diet-induced obesity

Interventions to prevent women from developing gestational diabetes mellitus: an overview of Cochrane Reviews

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) is increasing, with approximately 15% of pregnant women affected worldwide, varying by country, ethnicity and diagnostic thresholds. There are associated short- and long-term health risks for women and their babies.

OBJECTIVES

We aimed to summarise the evidence from Cochrane systematic reviews on the effects of interventions for preventing GDM.

METHODS

We searched the Cochrane Database of Systematic Reviews (6 August 2019) with key words 'gestational diabetes' OR 'GDM' to identify reviews pre-specifying GDM as an outcome. We included reviews of interventions in women who were pregnant or planning a pregnancy, irrespective of their GDM risk status. Two overview authors independently assessed eligibility, extracted data and assessed quality of evidence using ROBIS and GRADE tools. We assigned interventions to categories with graphic icons to classify the effectiveness of interventions as: clear evidence of benefit or harm (GRADE moderate- or high-quality evidence with a confidence interval (CI) that did not cross the line of no effect); clear evidence of no effect or equivalence (GRADE moderate- or high-quality evidence with a narrow CI crossing the line of no effect); possible benefit or harm (low-quality evidence with a CI that did not cross the line of no effect or GRADE moderate- or high-quality evidence with a wide CI); or unknown benefit or harm (GRADE low-quality evidence with a wide CI or very low-quality evidence).

MAIN RESULTS

We included 11 Cochrane Reviews (71 trials, 23,154 women) with data on GDM. Nine additional reviews pre-specified GDM as an outcome, but did not identify GDM data in included trials. Ten of the 11 reviews were judged to be at low risk of bias and one review at unclear risk of bias. Interventions assessed included diet, exercise, a combination of diet and exercise, dietary supplements, pharmaceuticals, and management of other health problems in pregnancy. The quality of evidence ranged from high to very low. Diet Unknown benefit or harm: there was unknown benefit or harm of dietary advice versus standard care, on the risk of GDM: risk ratio (RR) 0.60, 95% CI 0.35 to 1.04; 5 trials; 1279 women; very low-quality evidence. There was unknown benefit or harm of a low glycaemic index diet versus a moderate-high glycaemic index diet on the risk of GDM: RR 0.91, 95% CI 0.63 to 1.31; 4 trials; 912 women; low-quality evidence. Exercise Unknown benefit or harm: there was unknown benefit or harm for exercise interventions versus standard antenatal care on the risk of GDM: RR 1.10, 95% CI 0.66 to 1.84; 3 trials; 826 women; low-quality evidence. Diet and exercise combined Possible benefit: combined diet and exercise interventions during pregnancy versus standard care possibly reduced the risk of GDM: RR 0.85, 95% CI 0.71 to 1.01; 19 trials; 6633 women; moderate-quality evidence. Dietary supplements Clear evidence of no effect: omega-3 fatty acid supplementation versus none in pregnancy had no effect on the risk of GDM: RR 1.02, 95% CI 0.83 to 1.26; 12 trials; 5235 women; high-quality evidence. Possible benefit: myo-inositol supplementation during pregnancy versus control possibly reduced the risk of GDM: RR 0.43, 95% CI 0.29 to 0.64; 3 trials; 502 women; low-quality evidence. Possible benefit: vitamin D supplementation versus placebo or control in pregnancy possibly reduced the risk of GDM: RR 0.51, 95% CI 0.27 to 0.97; 4 trials; 446 women; low-quality evidence. Unknown benefit or harm: there was unknown benefit or harm of probiotic with dietary intervention versus placebo with dietary intervention (RR 0.37, 95% CI 0.15 to 0.89; 1 trial; 114 women; very low-quality evidence), or probiotic with dietary intervention versus control (RR 0.38, 95% CI 0.16 to 0.92; 1 trial; 111 women; very low-quality evidence) on the risk of GDM. There was unknown benefit or harm of vitamin D + calcium supplementation versus placebo (RR 0.33, 95% CI 0.01 to 7.84; 1 trial; 54 women; very low-quality evidence) or vitamin D + calcium + other minerals versus calcium + other minerals (RR 0.42, 95% CI 0.10 to 1.73; 1 trial; 1298 women; very low-quality evidence) on the risk of GDM. Pharmaceutical Possible benefit: metformin versus placebo given to obese pregnant women possibly reduced the risk of GDM: RR 0.85, 95% CI 0.61 to 1.19; 3 trials; 892 women; moderate-quality evidence. Unknown benefit or harm:eight small trials with low- to very low-quality evidence showed unknown benefit or harm for heparin, aspirin, leukocyte immunisation or IgG given to women with a previous stillbirth on the risk of GDM. Management of other health issues Clear evidence of no effect: universal versus risk based screening of pregnant women for thyroid dysfunction had no effect on the risk of GDM: RR 0.93, 95% CI 0.70 to 1.25; 1 trial; 4516 women; moderate-quality evidence. Unknown benefit or harm: there was unknown benefit or harm of using fractional exhaled nitrogen oxide versus a clinical algorithm to adjust asthma therapy on the risk of GDM: RR 0.74, 95% CI 0.31 to 1.77; 1 trial; 210 women; low-quality evidence. There was unknown benefit or harm of pharmacist led multidisciplinary approach to management of maternal asthma versus standard care on the risk of GDM: RR 5.00, 95% CI 0.25 to 99.82; 1 trial; 58 women; low-quality evidence.

AUTHORS' CONCLUSIONS

No interventions to prevent GDM in 11 systematic reviews were of clear benefit or harm. A combination of exercise and diet, supplementation with myo-inositol, supplementation with vitamin D and metformin were of possible benefit in reducing the risk of GDM, but further high-quality evidence is needed. Omega-3-fatty acid supplementation and universal screening for thyroid dysfunction did not alter the risk of GDM. There was insufficient high-quality evidence to establish the effect on the risk of GDM of diet or exercise alone, probiotics, vitamin D with calcium or other vitamins and minerals, interventions in pregnancy after a previous stillbirth, and different asthma management strategies in pregnancy. There is a lack of trials investigating the effect of interventions prior to or between pregnancies on risk of GDM.

Effective bifidogenic growth factors cyclo-Val-Leu and cyclo-Val-Ile produced by Bacillus subtilis C-3102 in the human colonic microbiota model

Bifidobacterium species are known to fulfill important functions within the human colon. Thus, stimulating the activity of bifidobacteria is important to maintain host health. We revealed that culture supernatants of Bacillus subtilis C-3102 (referred to as C-3102) stimulated the growth of Bifidobacterium species. In this study, we isolated and identified six bifidogenic growth factors, which were cyclo (D-Val-D-Ile), cyclo (L-Val-D-Ile), cyclo (D-Val-L-Ile), cyclo (L-Val-L-Ile), cyclo (D-Val-L-Leu) and cyclo (L-Val-L-Leu). These six cyclic dipeptides increased the growth of Bifidobacterium species and had no effect on potentially harmful gut organisms. Moreover, supplementation with a mixture of these six cyclic dipeptides significantly increased the abundance of microorganisms related to the genus Bifidobacterium in a human colonic microbiota model culture system, although supplementation with a single type of dipeptide had no effect. These results show that cyclic dipeptides containing Val-Leu and Val-Ile produced by C-3102 could serve as bifidogenic growth factors in the gut microbial community.

Dietary intake of bioactive ingredients impacts liver and adipose tissue transcriptomes in a porcine model of prepubertal early obesity

Global prevalence of obesity has increased to epidemic proportions over the past 40 years, with childhood obesity reaching alarming rates. In this study, we determined changes in liver and adipose tissue transcriptomes of a porcine model for prepubertal early obesity induced by a high-calorie diet and supplemented with bioactive ingredients. A total of 43 nine-weeks-old animals distributed in four pens were fed with four different dietary treatments for 10 weeks: a conventional diet; a western-type diet; and a western-type diet with Bifidobacterium breve and rice hydrolysate, either adding or not omega-3 fatty acids. Animals fed a western-type diet increased body weight and total fat content and exhibited elevated serum concentrations of cholesterol, whereas animals supplemented with bioactive ingredients showed lower body weight gain and tended to accumulate less fat. An RNA-seq experiment was performed with a total of 20 animals (five per group). Differential expression analyses revealed an increase in lipogenesis, cholesterogenesis and inflammatory processes in animals on the western-type diet while the supplementation with bioactive ingredients induced fatty acid oxidation and cholesterol catabolism, and decreased adipogenesis and inflammation. These results reveal molecular mechanisms underlying the beneficial effects of bioactive ingredient supplementation in an obese pig model.

Effect of probiotics on obesity-related markers per enterotype: a double-blind, placebo-controlled, randomized clinical trial

Background

Prevention and improvement of disease symptoms are important issues, and probiotics are suggested as a good treatment for controlling the obesity. Human gut microbiota has different community structures. Because gut microbial composition is assumed to be linked to probiotic function, this study evaluated the efficacy of probiotics on obesity-related clinical markers according to gut microbial enterotype.

Methods

Fifty subjects with body mass index over 25 kg/m² were randomly assigned to either the probiotic or placebo group. Each group received either unlabeled placebo or probiotic capsules for 12 weeks. Body weight, waist circumference, and body composition were measured every 3 weeks. Using computed tomography, total abdominal fat area and visceral fat area were measured. Blood and fecal samples were collected before and after the intervention for biochemical parameters and gut microbial compositions analysis.

Results

Gut microbial compositions of all the subjects were classified into two enterotypes according to Prevotella/Bacteroides ratio. The fat percentage, blood glucose, and insulin significantly increased in the Prevotella-rich enterotype of the placebo group. The obesity-related markers, such as waist circumference, total fat area, visceral fat, and ratio of visceral to subcutaneous fat area, were significantly reduced in the probiotic group. The decrease of obesity-related markers was greater in the Prevotella-rich enterotype than in the Bacteroides-rich enterotype.

Conclusion

Administration of probiotics improved obesity-related markers in obese people, and the efficacy of probiotics differed per gut microbial enterotype and greater responses were observed in the Prevotella-dominant enterotype.

Heat-Killed Bifidobacterium breve B-3 Enhances Muscle Functions: Possible Involvement of Increases in Muscle Mass and Mitochondrial Biogenesis

A previous clinical study on pre-obesity subjects revealed that Bifidobacteriumbreve B-3 shows anti-obesity effects and possibly increases muscle mass. Here, we investigated the effects of B-3 on muscle function, such as muscle strength and metabolism, and some signaling pathways in skeletal muscle. Male rodents were orally administered live B-3 (B-3L) or heat-killed B-3 (B-3HK) for 4 weeks. We found that administration of B-3 to rats tended to increase muscle mass and affect muscle metabolism, with stronger effects in the B-3HK group than in the B-3L group. B-3HK significantly increased muscle mass and activated Akt in the rat soleus. With regard to muscle metabolism, B-3HK significantly increased phosphorylated AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α and cytochrome c oxidase (CCO) gene expression in the rat soleus, suggesting an effect on the AMPK-PGC1α-mitochondrial biogenesis pathway. Furthermore, B-3HK promoted oxidative muscle fiber composition in the gastrocnemius. We also observed a significantly higher level of murine grip strength in the B-3HK group than in the control group. These findings suggest the potential of heat-killed B-3 in promoting muscle hypertrophy and modifying metabolic functions, possibly through the Akt and AMPK pathways, respectively.

Salivary Microbiological and Gingival Health Status Evaluation of Adolescents With Overweight and Obesity: A Cluster Analysis

Given the high prevalence of obesity in children and adolescents, the investigation of early markers is of clinical importance to better manage this condition. Thus, the aim was to evaluate the cross-sectional relationship between salivary microbiota, gingival health status, and excess weight in adolescents. A total of 248 students (14-17 y; 119 girls) were included, free of caries lesions and periodontal pockets. Physical examination included measures of height, weight, and body fat percentage (%BF). Oral examination was performed to gather information on dental (DMFT index) and gingival health status. Unstimulated saliva was submitted to qPCR reactions to quantify Streptococcus mutans, Porphyromonas gingivalis, Bifidobacteria, and Streptococcus pneumoniae percentages and the NFKappaB expression. Two-way ANOVA was applied considering group (normal-weight/overweight/obesity) and sex factors, in addition to cluster analysis. Group effect was significant for %S. mutans (partial eta² = 0.20; p < 0.001) and %Bifidobacteria (partial eta² = 0.19; p < 0.001), with overweight and obesity groups showing the highest levels compared to normal-weight ones, with no significant sex effect. There was no difference in the frequency of gingivitis, P. gingivalis, and S. pneumoniae percentages or NFKappaB expression between groups. Cluster analysis generated three clusters according to body fat accumulation: "Higher %BF," "Moderate %BF," and "Lower %BF." "Higher %BF" cluster was characterized by higher body fat percentage and higher salivary %Bifidobacteria, while cluster "Lower %BF" was characterized by lower body fat percentage and lower frequency of gingivitis ("Moderate %BF" cluster was the contrast). According to nutritional status, a difference in salivary S. mutans and Bifidobacteria percentages was found, with overweight or obesity adolescents showing the highest percentages than normal-weight ones. Besides, a positive relationship between body fat accumulation and Bifidobacteria count was observed, indicating a possible interaction between oral bacteria communities and weight gain.

International Society of Sports Nutrition Position Stand: Probiotics

Position statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of probiotic supplementation to optimize the health, performance, and recovery of athletes. Based on the current available literature, the conclusions of the ISSN are as follows: 1)Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host (FAO/WHO).2)Probiotic administration has been linked to a multitude of health benefits, with gut and immune health being the most researched applications.3)Despite the existence of shared, core mechanisms for probiotic function, health benefits of probiotics are strain- and dose-dependent.4)Athletes have varying gut microbiota compositions that appear to reflect the activity level of the host in comparison to sedentary people, with the differences linked primarily to the volume of exercise and amount of protein consumption. Whether differences in gut microbiota composition affect probiotic efficacy is unknown.5)The main function of the gut is to digest food and absorb nutrients. In athletic populations, certain probiotics strains can increase absorption of key nutrients such as amino acids from protein, and affect the pharmacology and physiological properties of multiple food components.6)Immune depression in athletes worsens with excessive training load, psychological stress, disturbed sleep, and environmental extremes, all of which can contribute to an increased risk of respiratory tract infections. In certain situations, including exposure to crowds, foreign travel and poor hygiene at home, and training or competition venues, athletes' exposure to pathogens may be elevated leading to increased rates of infections. Approximately 70% of the immune system is located in the gut and probiotic supplementation has been shown to promote a healthy immune response. In an athletic population, specific probiotic strains can reduce the number of episodes, severity and duration of upper respiratory tract infections.7)Intense, prolonged exercise, especially in the heat, has been shown to increase gut permeability which potentially can result in systemic toxemia. Specific probiotic strains can improve the integrity of the gut-barrier function in athletes.8)Administration of selected anti-inflammatory probiotic strains have been linked to improved recovery from muscle-damaging exercise.9)The minimal effective dose and method of administration (potency per serving, single vs. split dose, delivery form) of a specific probiotic strain depends on validation studies for this particular strain. Products that contain probiotics must include the genus, species, and strain of each live microorganism on its label as well as the total estimated quantity of each probiotic strain at the end of the product's shelf life, as measured by colony forming units (CFU) or live cells.10)Preclinical and early human research has shown potential probiotic benefits relevant to an athletic population that include improved body composition and lean body mass, normalizing age-related declines in testosterone levels, reductions in cortisol levels indicating improved responses to a physical or mental stressor, reduction of exercise-induced lactate, and increased neurotransmitter synthesis, cognition and mood. However, these potential benefits require validation in more rigorous human studies and in an athletic population.

Oral administration of heat-killed Lactobacillus brevis SBC8803 elevates the ratio of acyl/des-acyl ghrelin in blood and increases short-term food intake

It is known that gastrointestinal microbiota, probiotics and heat-killed microbes can regulate intestinal immunity; however, their effect on the secretion of gastrointestinal hormones is unclear. The secretion of gastrointestinal hormones can be mediated by the elevation of intracellular Ca2+ concentration, suggesting that these hormones may act through common mechanisms. We have previously shown that heat-killed Lactobacillus brevis SBC8803 (hk-SBC8803) induced the secretion of serotonin and elevated intracellular Ca2+ concentration in serotonin-producing RIN-14B cells, suggesting that hk-SBC8803 could potentially cause the same effect on other gastrointestinal hormones, including hunger hormone ghrelin. Here, we tested this hypothesis by treating cultured cells and experimental animals with hk-SBC8803 and assessing ghrelin secretion, expression of ghrelin-related genes, and food intake. The results indicated that hk-SBC8803 treatment for 30 min significantly upregulated the secretion of acyl ghrelin (active form) (P=0.046) and mRNA expression of the Syt3 (synaptotagmin 3) gene related to ghrelin exocytosis (P<0.05) in primary mouse stomach cells. In addition, oral administration of 500 mg/kg hk-SBC8803 to rats tended to upregulate acyl ghrelin concentration (P=0.10) and significantly increased the ratio of acyl to des-acyl (inactive) ghrelin (P=0.027) in blood, which corresponded to a tendency of stimulating food intake (P=0.087) at 30 min post-treatment. However, when in order to minimise individual differences we normalised the data on food intake to those on one-day food intake prior to food deprivation, the resultant food intake ratio showed a significant increase (by 5% compared to control; P=0.032) at 30 min after hk-SBC8803 treatment, indicating that hk-SBC8803 administration stimulated rats to take more food during the first meal after fasting. These results suggest that hk-SBC8803 induces short-term ghrelin secretion and transiently increases appetite, which is an important effect for individuals with low energy intake.

L. plantarum, L. fermentum, and B. breve Beads Modified the Intestinal Microbiota and Alleviated the Inflammatory Response in High-Fat Diet-Fed Mice

This paper aims to study the effects of compound microbe-based beads on changes in the intestinal microbiota and alleviation of high-fat (HF) diet-induced inflammatory responses. Forty-eight mice were fed base chow or a high-fat diet for 4 weeks and then randomly separated into six groups: normal diet (group A), high-fat diet (group B), high-fat positive control (fed with high-fat chow plus Tetrahydrolipstatin, group C), high-fat chow plus B. breve beads (group D), high-fat chow plus L. plantarum-L. fermentum beads (group E), and high-fat chow plus L. plantarum-L. fermentum-B. breve beads (group F). The body weights were measured. The serum cytokine and lipid levels were determined by ELISA, and high-throughput sequence analysis of the fecal microbiota was conducted. Beads with cell encapsulation rates higher than 99% decreased the body weight from 50.97 ± 3.44 g in group B to 42.64 ± 2.63 g in group F at the end of the experiment (p = 0.00019). The total cholesterol content in group F was 80.14 ± 9.37 mmol/L, which was significantly lower than that in group A (96.13 ± 24.07 mmol/L) (p = 0.02765), group B (102.52 ± 12.20 mmol/L) (p = 0.00196), and group C (98.99 ± 11.32 mmol/L) (p = 0.00804). In addition, the serum IL-6 level showed no significant difference between group F and the base chow control group. The microbial cell-loaded bead intervention led to increased abundances of Bifidobacterium and Lactobacillus in mouse feces. Oral administration of three strain-based beads led to alleviation of inflammatory reactions in high-fat diet-fed mice.

Heat-killed Lactobacillus helveticus strain MCC1848 confers resilience to anxiety or depression-like symptoms caused by subchronic social defeat stress in mice

The gut microbiota is involved in the pathogenesis of stress-related disorders. Probiotics can benefit the central nervous system via the microbiota–gut–brain axis, which raises the possibility that probiotics are effective in managing depression. In the present study, we examined the effects of heat-killed Lactobacillus helveticus strain MCC1848 in subchronic and mild social defeat stress (sCSDS) model mice (a widely used animal model of depression). MCC1848 supplementation significantly enhanced the interaction time in the social interaction test and sucrose preference ratio in the sucrose preference test, suggesting that MCC1848 improved anxiety- or depressive-like behaviors in sCSDS mice. The gene expression profile analysis of the nucleus accumbens, which plays an important role in stress resilience, indicated that MCC1848 ameliorated sCSDS-induced gene expression alterations in signal transduction or nervous system development. These findings suggest that MCC1848 supplementation is useful as a preventive strategy for chronic-stress-induced depression.

Interventions to prevent women developing gestational diabetes mellitus: an overview of Cochrane Reviews

This is a protocol for a Cochrane Review (Overview). The objectives are as follows:

To summarise the evidence from Cochrane systematic reviews regarding the effects of interventions to prevent women developing gestational diabetes mellitus (GDM).

The role of diet and intestinal microbiota in the development of metabolic syndrome

Metabolic syndrome (MetS) is a cluster of metabolic factors that increase the risk of cardiovascular disease and type 2 diabetes mellitus (T2DM), which is in itself a major cardiovascular disease risk factor. The aim of this review is to summarize the data related to the influence of the gut microbiota on the development of obesity and the MetS, highlighting the role of diet in controlling the MetS by modifying the gut microbiota. The main alterations in the gut microbiota of individuals with MetS consist of an increased Firmicutes/Bacteriodetes ratio and a reduced capacity to degrade carbohydrates to short-chain fatty acids, which in turn is related with the metabolic dysfunction of the host organism rather than with obesity itself. In addition to a low-fat, high-carbohydrate diet, with its high fiber intake, a diet with 30% fat content but with a high content in fruit and vegetables, such as the Mediterranean diet, is beneficial and partially restores the dysbiosis found in individuals with MetS. Overall, the shaping of the gut microbiota through the administration of prebiotics or probiotics increases the short-chain fatty acid production and is therefore a valid alternative in MetS treatment.

Gut microbiota and obesity: An opportunity to alter obesity through faecal microbiota transplant (FMT)

Obesity is a global pandemic with immense health consequences for individuals and societies. Multiple factors, including environmental influences and genetic predispositions, are known to affect the development of obesity. Despite an increasing understanding of the factors driving the obesity epidemic, therapeutic interventions to prevent or reverse obesity are limited in their impact. Manipulation of the human gut microbiome provides a new potential therapeutic approach in the fight against obesity. Specific gut bacteria and their metabolites are known to affect host metabolism and feeding behaviour, and dysbiosis of this biosystem may lead to metabolic syndrome. Potential therapies to alter the gut microbiota to treat obesity include dietary changes, supplementation of the diet with probiotic organisms and prebiotic compounds that influence bacterial growth, and the use of faecal microbiota transplant, in which gut microbiota from healthy individuals are introduced into the gut. In this review, we examine the growing scientific evidence supporting the mechanisms by which the human gut microbiota may influence carbohydrate metabolism and obesity, and the various possible therapies that may utilize the gut microbiota to help correct metabolic dysfunction.

Bioactive factors secreted by Bifidobacterium breve B-3 enhance barrier function in human intestinal Caco-2 cells

Intestinal barrier function is closely related to intestinal health and diseases. Recent studies demonstrate that some probiotic and commensal bacteria secrete metabolites that are capable of affecting the intestinal functions. The present study examined an enhancing effect of bioactive factors secreted by Bifidobacterium breve strain B-3 on the intestinal tight junction (TJ) barrier integrity in human intestinal Caco-2 cells. Administration of conditioned medium obtained from B. breve strain B-3 (B3CM) to Caco-2 cells for 24 h increased trans-epithelial electrical resistance (TER), a TJ barrier indicator, across their monolayers. Immunoblot, immunofluorescence, and qPCR analyses demonstrated that B3CM increased an integral TJ protein, claudin-4 expression. In luciferase reporter assay, the administration of B3CM enhanced the claudin-4 promoter activity, indicating the transcriptional upregulation of claudin-4. Site-directed mutation of specificity protein 1 (Sp1) binding sites in the claudin-4 promoter sequence and suppression of Sp1 expression by siRNA technology clearly reduced the enhancing effect of B3CM on claudin-4 promoter activity. Liquid chromatography/mass spectrometry detected a significant amount of acetic acid in B3CM (28.3 mM). The administration of acetic acid to Caco-2 cells partially mimicked a B3CM-mediated increase in TER, but failed to increase claudin-4 expression. Taken together, bioactive factors secreted by B. breve B-3 enhanced the TJ barrier integrity in intestinal Caco-2 cells. Transcriptional regulation of claudin-4 through Sp1 is at least in part one of the underlying molecular mechanisms. In addition, acetic acid contributes to the B3CM-mediated barrier effect independently of claudin-4 expression.

Diet, Gut Microbiota, and Obesity: Links with Host Genetics and Epigenetics and Potential Applications

Diverse evidence suggests that the gut microbiota is involved in the development of obesity and associated comorbidities. It has been reported that the composition of the gut microbiota differs in obese and lean subjects, suggesting that microbiota dysbiosis can contribute to changes in body weight. However, the mechanisms by which the gut microbiota participates in energy homeostasis are unclear. Gut microbiota can be modulated positively or negatively by different lifestyle and dietary factors. Interestingly, complex interactions between genetic background, gut microbiota, and diet have also been reported concerning the risk of developing obesity and metabolic syndrome features. Moreover, microbial metabolites can induce epigenetic modifications (i.e., changes in DNA methylation and micro-RNA expression), with potential implications for health status and susceptibility to obesity. Also, microbial products, such as short-chain fatty acids or membrane proteins, may affect host metabolism by regulating appetite, lipogenesis, gluconeogenesis, inflammation, and other functions. Metabolomic approaches are being used to identify new postbiotics with biological activity in the host, allowing discovery of new targets and tools for incorporation into personalized therapies. This review summarizes the current understanding of the relations between the human gut microbiota and the onset and development of obesity. These scientific insights are paving the way to understanding the complex relation between obesity and microbiota. Among novel approaches, prebiotics, probiotics, postbiotics, and fecal microbiome transplantation could be useful to restore gut dysbiosis.

Therapeutic Microbiology: The Role of Bifidobacterium breve as Food Supplement for the Prevention/Treatment of Paediatric Diseases

The human intestinal microbiota, establishing a symbiotic relationship with the host, plays a significant role for human health. It is also well known that a disease status is frequently characterized by a dysbiotic condition of the gut microbiota. A probiotic treatment can represent an alternative therapy for enteric disorders and human pathologies not apparently linked to the gastrointestinal tract. Among bifidobacteria, strains of the species Bifidobacterium breve are widely used in paediatrics. B. breve is the dominant species in the gut of breast-fed infants and it has also been isolated from human milk. It has antimicrobial activity against human pathogens, it does not possess transmissible antibiotic resistance traits, it is not cytotoxic and it has immuno-stimulating abilities. This review describes the applications of B. breve strains mainly for the prevention/treatment of paediatric pathologies. The target pathologies range from widespread gut diseases, including diarrhoea and infant colics, to celiac disease, obesity, allergic and neurological disorders. Moreover, B. breve strains are used for the prevention of side infections in preterm newborns and during antibiotic treatments or chemotherapy. With this documentation, we hope to increase knowledge on this species to boost the interest in the emerging discipline known as "therapeutic microbiology".

Effect of combined bifidobacteria supplementation and resistance training on cognitive function, body composition and bowel habits of healthy elderly subjects

Physical exercise exerts favourable effects on brain health and quality of life of the elderly; some of these positive health effects are induced by the modulation of microbiota composition. We therefore conducted a randomised, double blind, placebo-controlled trial that assessed whether a combination of Bifidobacterium spp. supplementation and moderate resistance training improved the cognitive function and other health-related parameters in healthy elderly subjects. Over a 12-week period, 38 participants (66-78 years) underwent resistance training and were assigned to the probiotic Bifidobacterium supplementation (n=20; 1.25×10¹⁰ cfu each of Bifidobacterium longum subsp. longum BB536, B. longum subsp. infantis M-63, Bifidobacterium breve M-16V and B. breve B-3) or the placebo (n=18) group. At baseline and at 12 weeks, we assessed the cognitive function, using the Japanese version of the Montreal Cognitive Assessment instrument (MoCA-J); modified flanker task scores; depression-anxiety scores; body composition; and bowel habits. At 12 weeks, the MoCA-J scores showed a significant increase in both the groups, while the flanker task scores of the probiotic group increased more significantly than those of the placebo group (0.35±0.9 vs -0.29±1.1, P=0.056). Only the probiotic group showed a significant decrease in the depression-anxiety scores (5.2±6.3 to 3.4±5.5, P=0.012) and body mass index (24.0±2.8 to 23.5±2.8 kg/m², P<0.001), with a significant increase in the defecation frequency (5.3±2.3 to 6.4±2.3 times/5 days, P=0.023) at 12 weeks. Thus, in healthy elderly subjects, combined probiotic bifidobacteria supplementation and moderate resistance training may improve the mental condition, body weight and bowel movement frequency.

Effect of alive probiotic on insulin resistance in type 2 diabetes patients: Randomized clinical trial

BACKGROUND

Probiotics have beneficial effect on obesity related disorders in animal models. Despite a large number of animal data, randomized placebo-controlled trials (RCT) concluded that probiotics have a moderate effect on glycemic control-related parameters. However, effect of probiotics on insulin resistance are inconsistent.

AIM

In a double-blind single center RCT, effect of alive multistrain probiotic vs. placebo on insulin resistance in type 2 diabetes patient were assessed.

METHODS

A total of 53 patients met the criteria for inclusion. They were randomly assigned to receive multiprobiotic "Symbiter" (concentrated biomass of 14 probiotic bacteria genera Bifidobacterium, Lactobacillus, Lactococcus, Propionibacterium) or placebo for 8-weeks administered as a sachet formulation. The primary main outcome was the change HOMA-IR (homeostasis model assessment-estimated insulin resistance) which calculated using Matthews et al.'s equation. Secondary outcomes were the changes in glycemic control-related parameters, anthropomorphic variables and cytokines.

RESULTS

Supplementation with alive multiprobiotic for 8 weeks was associated with significant reduction of HOMA-IR from 6.85 ± 0.76 to 5.13 ± 0.49 (p = 0.047), but remained static in the placebo group. With respect to our secondary outcomes, HbA1c insignificant decreased by 0.09% (p = 0.383) and 0.24% (p = 0.068) respectively in placebo and probiotics groups. However, in probiotic responders (n = 22, patient with decrease in HOMA-IR) after supplementation a significant reduction in HbA1c by 0.39% (p = 0.022) as compared to non-responders was observed. In addition, from markers of chronic systemic inflammatory state only TNF-α and IL-1β changes significantly after treatment with probiotics.

CONCLUSION

Probiotic therapies modestly improved insulin resistance in patients with type 2 diabetes.

Anti-obesity properties of the strain Bifidobacterium animalis subsp. lactis CECT 8145 in Zücker fatty rats

We evaluated the effect of oral administration of Bifidobacterium animalis subsp. lactis CECT 8145 strain in Zücker fatty rats. The Zücker fatty rats were randomly divided into two groups (n=10 each) and administered either B. animalis subsp. lactis CECT 8145 (1010 cfu/day) suspended in skim milk, or skim milk alone (control group). Each treatment was administered in drinking bottles from week 5 until week 17 of age. A lean Zücker rat group (standard group) was included to provide normal values for the Zücker strain. This group was administered skim milk in the drinking bottle for the same experimental period as Zücker fatty rats. Body weight gain was greater in the fatty control group than in the fatty rats treated daily with B. animalis subsp. lactis CECT 8145. Furthermore, dry and liquid food intake significantly decreased in the treated Zücker fatty group and these rats also showed decreased plasma ghrelin levels as compared with the Zücker fatty control group. B. animalis subsp. lactis CECT 8145 intake also decreased plasma tumour necrosis factor-α (a proinflammatory cytokine) and plasma malondialdehyde (a biomarker of oxidative stress). Moreover, the ratio plasma total cholesterol/plasma cholesterol transported by high-density lipoproteins, considered as an index for cardiovascular disease, also significantly decreased in the Zücker fatty rats treated with B. animalis subsp. lactis CECT 8145. By contrast, this bacterial strain significantly increased plasma adiponectin (an insulin-sensitising adipokine), but did not produce significant effects on triglyceride levels or glucose metabolism biomarkers. Although further research is required to confirm B. animalis subsp. lactis CECT 8145 is an efficient anti-obesity treatment in humans, the results obtained in this study are promising and point to the health and anti-obesity properties of this bacterial strain.

Influence of the microbiota and probiotics in obesity

Gut microbiota plays a key role in the control of body weight. In the present review the different ways in which it can modify the energy homeostasis of the host are exposed, based on its capacity to modify the metabolism of the individual and its contribution in the energy consumption regulation. With the current evidence, it is not clear what microbiota profile is associated with the presence of obesity, although in animal models it seems to be related to a higher proportion of bacteria of the Firmicutes phylum, to the detriment of those of the Bacteroidetes phylum. Other factors clearly involved would be the diversity in the gut microbiota or its possible functional changes. More studies in humans are needed to clarify how dysbiosis can influence weight control. On the other hand, probiotics directly affect the gut microbiota, modulating its composition and, possibly, its functionality. A large number of studies in humans have evaluated the impact of probiotics on obesity. Although this intervention may have a potentially beneficial effect, more effort is needed to clarify which strains of probiotics should be recommended, at what dose and for how long.

Sterilized bifidobacteria suppressed fat accumulation and blood glucose level

Probiotics such as Lactobacillus and Bifidobacterium improve the balance of intestinal microflora and have various physiological functions beneficial to human health. It is not always known whether the ingested microbial cells are viable- or killed. However, even sterilized bacterial cells are functional. Bacterial cell functions are strain-specific and their modes of action are still poorly understood. The aim of this study was to elucidate the roles of sterilized bifidobacteria in obesity and lipid metabolism. To this end, mice were orally ingested sterilized bacteria. Male C57BL/6J mice aged 7 wks were raised on a high-fat diet and received oral sterilized bifidobacteria for 4 wks. Although the amount of food they ingested did not change in response to bifidobacteria administration, both weight gain and epididymal body fat mass were significantly reduced. In addition, the elevated blood glucose, triglyceride, and total cholesterol levels observed in the mice on the high-fat diet all decreased in response to bifidobacteria treatment. Hepatic triglyceride levels also decreased. Furthermore, oral glucose tolerance and insulin resistance tests indicated that sterilized bifidobacteria improved glucose tolerance and diminished insulin resistance. Sterilized bifidobacteria also decreased blood lipopolysaccharides and altered intestinal flora. The present study indicates that in mice on a high-fat diet, sterilized bifidobacteria suppressed fat accumulation, improved insulin resistance, and lowered blood glucose levels.

Effects of Bifidobacterium breve B-3 on body fat reductions in pre-obese adults: a randomized, double-blind, placebo-controlled trial

Accumulating evidence suggests a relationship between the gut microbiota and the development of obesity, indicating the potential of probiotics as a therapeutic approach. Bifidobacterium breve B-3 has been shown to exert anti-obesity effects in high-fat diet-induced obese mice. In the present study, the anti-obesity effects of the consumption of B. breve B-3 by healthy pre-obese (25 ≤ BMI < 30) adults were investigated in a randomized, double-blind, placebo-controlled trial (trial registration: UMIN-CTR No. 000023919; preregistered on September 2, 2016). Eighty participants were randomized to receive placebo or B. breve B-3 capsules (2 × 10¹⁰ CFU/day) daily for 12 weeks. The visceral fat area significantly increased at weeks 4 and 8 in the placebo group only; no significant change was observed in the B-3 group. Body fat mass and percent body fat were significantly lower in the B-3 group than in the placebo group at weeks 8 and 12 (p<0.05, ANCOVA adjusted with baseline values). Although no significant differences were observed in blood parameters between the groups, the intake of B. breve B-3 slightly decreased triglyceride levels and improved HDL cholesterol from the baseline. No serious adverse effects were noted in either group. These results suggest that the probiotic strain B. breve B-3 has potential as a functional food ingredient to reduce body fat in healthy pre-obese individuals.

The Effects of Synbiotic Supplementation on Body Mass Index, Metabolic and Inflammatory Biomarkers, and Appetite in Patients with Metabolic Syndrome: A Triple-Blind Randomized Controlled Trial

It has been shown recently that metabolic syndrome is associated with gut dysbiosis. The gut microbiota may be the main target for prevention or treatment of metabolic syndrome. We investigated the effects of synbiotic supplementation on metabolic syndrome. In this triple-blinded clinical trial, 46 Iranian patients with metabolic syndrome, from both sexes, aged 25-70 years, who fulfilled inclusion criteria were randomly categorized to receive either the synbiotic or a placebo capsule, twice a day for three months, plus a weight-loss diet using stratified random sampling based on body mass index (BMI). Each synbiotic capsule consisted of seven strains probiotic bacteria (2× 10⁸) plus fructooligosaccharide as a prebiotic. Anthropometric measurements and biochemical tests were assessed at baseline and at the end of week 12 for fasting blood sugar (FBS), insulin, lipid profile, high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), peptide YY (PYY), and glucagon-like peptide-1 (GLP-1). The mean changes of weight, BMI, FBS, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), and GLP-1 between the two groups was statistically significant (p < .001). Furthermore, peptide YY (PYY) increased significantly in the synbiotic group (p ≤ .05). The trend of weight loss in the synbiotic group was significant until the end of the study (p < .001) while it stopped at week 6 in the placebo group. Synbiotic treatment may improve the status of BMI, FBS, insulin resistance, HOMA-IR, GLP-1, and PYY in patients with metabolic syndrome.

Modulation of Active Gut Microbiota by Lactobacillus rhamnosus GG in a Diet Induced Obesity Murine Model

Gut microbiota play a key role in the development of metabolic disorders. Defining and correlating structural shifts in gut microbial assemblages with conditions related to metabolic syndrome have, however, been proven difficult. Results from 16S genomic DNA and 16S ribosomal RNA analyses of fecal samples may differ widely, leading to controversial information on the whole microbial community and metabolically active microbiota. Using a C57BL/6J murine model, we compared data from 16S genomic DNA and ribosomal RNA of the fecal microbiota. The study included three groups of experimental animals comprising two groups with high fat diet induced obesity (DIO) while a third group (control) received a low fat diet. One of the DIO groups was treated with the probiotic Lactobacillus rhamnosus GG (LGG). Compared to the data obtained by DNA analysis, a significantly higher abundance of OTUs was accounted for by RNA analysis. Moreover, rRNA based analysis showed a modulation of the active gut microbial population in the DIO group receiving LGG, thus reflecting a change in the induced obesity status of the host. As one of the most widely studied probiotics the functionality of LGG has been linked to the alleviation of metabolic syndrome, and, in some cases, to an impact on the microbiome. Yet, it appears that no study has reported thus far on modulation of the active microbiota by LGG treatment. It is postulated that the resulting impact on calorie consumption affects weight gain concomitantly with modulation of the functional structure of the gut microbial population. Using the 16S rRNA based approach therefore decisively increased the precision of gut microbiota metagenome analysis.

Perinatal microbial exposure may influence aortic intima-media thickness in early infancy

Background

The maternal and infant microbiome may influence infant cardiovascular risk through immune programming. The maternal vagino-enteric microbiome is often sampled for group B streptococcus (GBS) colonization during pregnancy. Our aim was to investigate the association between maternal GBS colonization, intrapartum antibiotics, antenatal pet exposure and infant aortic intima-media thickness (aIMT), an intermediate vascular phenotype, and whether this association varied by mode of delivery.

Methods

The Barwon Infant Study is a population-derived pre-birth cohort. Perinatal data were collected on participants. Women were tested for vagino-enteric group B streptococcus (GBS) colonization during third trimester. Six-week infant aIMT was measured by trans-abdominal ultrasound. Adjustment for confounders included maternal age, pre-pregnancy body mass index (BMI), smoking, socioeconomic status, gestational diabetes, length of gestation, infant sex, birthweight and aortic internal diameter.

Results

Data were available on 835 mother-infant pairs. Of these, 574 (69%) women delivered vaginally; of those, 129 (22%) were GBS-colonized; and of these women, 111 (86%) received prophylactic intrapartum antibiotics. An association between maternal GBS colonization and infant aIMT was observed among those delivered vaginally (β = 19.5 µm, 95% CI 9.5, 29.4; P  < 0.0001) but not by Caesarean section ( P for interaction = 0.02). A similar pattern was seen for intrapartum antibiotics. There was a negative association between antenatal pet exposure and aIMT observed in those delivered vaginally.

Conclusion

Maternal GBS colonization and intrapartum antibiotics were associated with increased infant aIMT in those delivered vaginally, whereas antenatal pet exposure was associated with decreased aIMT. These data suggest that differences in early life microbial experience may contribute to an increased cardiovascular risk.

Bifidobacteria and its rice fermented products on diet induced obese mice: analysis of physical status, serum profile and gene expressions

Obesity is highly correlated with the dysbiosis of intestinal microbiota, and bifidobacteria are one of the soft targets of this metabolic syndrome. The aim of this study is to evaluate the efficacy of Bifidobacterium sp. MKK4 and rice-based fermented foods on physical, haematological, gut microbiota and lypogenic-lypolytic marker genes in diet-induced obese mice. Adult male mice (21±0.7 g) were randomly divided into four groups (n=10) according to the type of diet: normal diet (ND), high fat diet (HFD), HFD supplemented with Bifidobacterium sp. MKK4 and HFD supplemented with MKK4 associated rice-fermented food. 8 weeks of bacterial therapy in the obese mice resulted in significant reduction of body and organ weights, improved serum levels of glucose, triglyceride and cholesterol, the histological structure of the liver (steatosis), and re-establishment of gut Lactobacillus, Bifidobacterium and Bacteroides species. The bacterial therapy led to up-regulation of lipolytic transcription factors, such as peroxisome proliferator-activated receptor (PPAR)-α, PPAR-δ, and their regulated gene products in fatty acid metabolism and glucose uptake, such as acyl-CoA oxidase, carnitine palmitoyl-transferase-1, uncoupling protein-3 and glucose transporter-4. Concomitantly, both adipocytogenesis and fatty acid synthesis were arrested as reflected by the down-regulation of sterol regulatory element binding protein-1c, acetyl-CoA carboxylase, fatty acid synthase and tumour necrosis factor alpha genes. The effectiveness of the fermented product was more profound than the single bacterium. These data provide experimental support with regard to the use of Bifidobacterium sp. MKK4 as a natural therapeutic agent to control obesity.

Safety evaluation of Bifidobacterium breve MCC1274 via oral toxicity tests in rats

In this study, the safety of Bifidobacterium breve MCC1274, a probiotic bifidobacterial strain, was assessed by single-dose and 90-day repeated-dose oral toxicity studies. In the single-dose oral toxicity assay using 6000 mg/kg of B. breve MCC1274 corresponding to 8.4 × 1011 colony-forming unit (CFU)/kg, mortality and adverse effects were not observed. Furthermore, the administration of 1000 mg/kg of B. breve MCC1274 by oral gavage in saline for 90 days did not induce any signs of toxicity, such as changes in clinical signs, body weight (BW), food consumption, ophthalmoscopy, urinalysis, hematology, blood chemistry, organ weight, gross pathology, and histopathology compared to the control group given cornstarch in saline (10/sex/group). The no-observed-adverse-effect-level of B. breve MCC1274 in the 90-day repeated-dose toxicity study was greater than 1000 mg/kg corresponding to 1.3 × 1011 CFU/kg. Based on the findings of this study, the acceptable daily intake of B. breve MCC1274 was calculated to be 1.3 × 109 CFU/kg BW/day.

Comparative study of probiotic effects of Lactobacillus and Bifidobacteria strains on cholesterol levels, liver morphology and the gut microbiota in obese mice

BACKGROUND

Microbiome-modulating interventions are promising for treatment and prevention of metabolic syndrome. The number of probiotic strains demonstrated ability to decrease cholesterol level in vivo, however, it was poorly confirmed in a clinical setting. The aim was to study the effects of L. acidophilus IMV B-7279, L. casei IMV B-7280, B. animalіs VKL and B. animalіs VKB separately and in various compositions on the level of serum cholesterol, gut microbiota contents and liver morphology on a high-calorie-induced obesity model in BALB/c mice.

MATERIALS AND METHODS

We used for the study female BALB/c mice 6-8 weeks old (18-24 g). Experimental animals were fed by a fat-enriched diet (FED), and 8 experimental groups were formed (12 mice in each group) to test strains of probiotic bacteria L. delbrueckii subsp. bulgaricus IMV B-7281, L. casei IMV B-7280, B. animalіs VKL and B. animalіs VKB and compositions. We used ultrasound for in vivo assessment of the liver and visceral (mesenteric) fat size. In the blood serum of the obese mice, the level of cholesterol was estimated. The liver morphology and gut microbiota of obese mice were studied.

RESULTS

We revealed that after treatment with all of the studied probiotic bacteria and compositions of B. animalis VKL/B. animalis VKB/L. casei IMV B-7280, the weight of obese mice decreased, and cholesterol and its fraction levels in serum were reduced. The size of the liver slightly decreased after treatment with L. delbrueckii subsp. bulgaricus IMV B-7281, B. аnimalis VKB or probiotic compositions; we observed reduction of the mesenteric fat size after injection of all these probiotic bacteria (separately) and probiotic compositions. We defined the strain-dependent effects on serum lipid profiles, liver morphology and the gut microbiota. The B. animalis VKL/B. animalis VKB/L. casei IMV B-7280 composition effectively recovered the liver morphological structure of obese mice. The number of Lactobacillus spp., Bifidobacterium spp. and coliform bacteria increased, the number of staphylococci and streptococci reduced, and the number of microscopic fungi significantly decreased in the gut of obese mice after treatment with L. casei IMV B-7280, L. delbrueckii subsp. bulgaricus IMV B-7281, B. animalis (separately) or their compositions.

CONCLUSION

L. casei IMV B-7280 (separately) and a composition of B. animalis VKL/B. animalis VKB/L. casei IMV B-7280 are effective at decreasing the weight of obese mice, decreasing cholesterol level, restoring the liver morphology and beneficially modulating the gut microbiome in high-calorie-induced obesity.

Probiotic strains and mechanistic insights for the treatment of type 2 diabetes

INTRODUCTION

The intestinal microbial composition appears to differ between healthy controls and individuals with Type 2 diabetes (T2D). This observation has led to the hypothesis that perturbations of the intestinal microbiota may contribute to the development of T2D. Manipulations of the intestinal microbiota may therefore provide a novel approach in the prevention and treatment of T2D. Indeed, fecal transplants have shown promising results in both animal models for obesity and T2D and in human clinical trials. To avoid possible complications associated with fecal transplants, probiotics are considered as a viable alternative therapy. An important, however often underappreciated, characteristic of probiotics is that individual strains may have different, even opposing, effects on the host. This strain specificity exists also within the same species. A comprehensive understanding of the underlying mechanisms at the strain level is therefore crucial for the selection of suitable probiotic strains.

PURPOSE

The aim of this review is to discuss the mechanisms employed by specific probiotic strains of the Lactobacillus and the Bifidobacterium genuses, which showed efficacy in the treatment of obesity and T2D. Some probiotic strains employ recurring beneficial effects, including the production of anti-microbial lactic acid, while other strains display highly unique features, such as hydrolysis of tannins.

CONCLUSION

A major obstacle in the evaluation of probiotic strains lays in the great number of strains, differences in detection methodology and measured outcome parameters. The understanding of further research should be directed towards the development of standardized evaluation methods to facilitate the comparison of different studies.

Therapeutic potential of Bifidobacterium breve strain A1 for preventing cognitive impairment in Alzheimer's disease

It has previously been shown that the consumption of probiotics may have beneficial effects not only on peripheral tissues but also on the central nervous system and behavior via the microbiota-gut-brain axis, raising the possibility that treatment with probiotics could be an effective therapeutic strategy for managing neurodegenerative disorders. In this study, we investigated the effects of oral administration of Bifidobacterium breve strain A1 (B. breve A1) on behavior and physiological processes in Alzheimer's disease (AD) model mice. We found that administration of B. breve A1 to AD mice reversed the impairment of alternation behavior in a Y maze test and the reduced latency time in a passive avoidance test, indicating that it prevented cognitive dysfunction. We also demonstrated that non-viable components of the bacterium or its metabolite acetate partially ameliorated the cognitive decline observed in AD mice. Gene profiling analysis revealed that the consumption of B. breve A1 suppressed the hippocampal expressions of inflammation and immune-reactive genes that are induced by amyloid-β. Together, these findings suggest that B. breve A1 has therapeutic potential for preventing cognitive impairment in AD.

Lactobacillus rhamnosus PB01 (DSM 14870) supplementation affects markers of sperm kinematic parameters in a diet-induced obesity mice model

Probiotics have been proposed as alternatives to pharmacological products in several medical conditions including the modulation of obesity, which is frequently associated with poor semen quality. However, effects of probiotics on male fertility have been less investigated. This study assessed the effect of Lactobacillus rhamnosus PB01 (DSM-14870) on sperm kinematic parameters in Normal-weight (NW) and diet-induced obese (DIO) models. NW and DIO C57BL/6NTac mice were divided into two subgroups with or without a single daily dose (1x109CFU) of L. rhamnosus for four weeks. Sperm motility and kinematics together with blood lipid profiles and reproductive hormone levels were assessed using the sperm class analyzer system. Probiotic supplementation increased serum testosterone, LH and FSH levels in both NW and DIO groups resulting in significantly (P<0.05) higher velocity (VSL, VCL and VAP) and percentages of progressively motile sperm and significantly lower percentages of immotile sperm. Other kinematic parameters (Lin, STR, ALH and BCF) were also increased in both probiotic supplemented DIO and NW groups at the 10% level of significance. Probiotic supplemented DIO mice demonstrated significantly higher percentages of progressively motile sperm versus DIO controls. This study demonstrated the potential of L. rhamnosus PB01 as a regulatory agent with positive effects on weight loss and reproductive-hormones, significantly improving sperm motility and kinematic parameters in male DIO models.

The anti-cholesterolaemic effect of a consortium of probiotics: An acute study in C57BL/6J mice

Hypercholesterolaemia is a major risk factor for cardiovascular disease and it has been found that some probiotic bacteria possess cholesterol-lowering capabilities. In this study, the ability of the Lab4 probiotic consortium to hydrolyse bile salts, assimilate cholesterol and regulate cholesterol transport by polarised Caco-2 enterocytes was demonstrated. Furthermore, in wild-type C57BL/6J mice fed a high fat diet, 2-weeks supplementation with Lab4 probiotic consortium plus Lactobacillusplantarum CUL66 resulted in significant reductions in plasma total cholesterol levels and suppression of diet-induced weight gain. No changes in plasma levels of very low-density lipoprotein/low-density lipoprotein, high-density lipoprotein, triglycerides, cytokines or bile acids were observed. Increased amounts of total and unconjugated bile acids in the faeces of the probiotic-fed mice, together with modulation of hepatic small heterodimer partner and cholesterol-7α-hydroxylase mRNA expression, implicates bile salt hydrolase activity as a potential mechanism of action. In summary, this study demonstrates the cholesterol-lowering efficacy of short-term feeding of the Lab4 probiotic consortium plus L. plantarum CUL66 in wild-type mice and supports further assessment in human trials.

Some current applications, limitations and future perspectives of lactic acid bacteria as probiotics

Several mechanism and non-mechanism-based studies supporting the claim that lactic acid bacteria (LAB) strains confer health benefits and play immune-modulatory roles were examined in this review. Probiotic applications of LAB on global burdens such as obesity and type-2 diabetes were discussed as well as the use of yoghurt and ice cream as important vehicles to convey several beneficial LAB strains. Probiotic and symbiotic dairy products may be used in the nearest future to treat a variety of health disorders. Current studies suggest that lactic acid bacteria possess anti-obesity and anti-diabetic propensities on their hosts and thus can play a crucial role in human health care. Research in the rheological and physicochemical properties of ice cream as well as its applications are also on the increase. These applications face certain hurdles including technological (for less developed countries), consumer acceptability of new functional foods may be influenced by culture, ethics or religion. There is need for more studies on the genetic basis for probiotic properties which will give further understanding regarding novel manipulation skills and applicability in nutrition and health sectors. More studies confirming the direct effects of probiotic LABs in lowering the spread of food-borne and other pathogens are also anticipated.

Rice- or pork-based diets with similar calorie and content result in different rat gut microbiota

Rice is the most important food crop, and pork is the most widely eaten meat in the world. In this study, we compared the gut microbiota of the rats fed with rice or pork mixed diets, which have similar caloric contents. The physiological indices (body weights, hematology, serum chemistry, organ weights and histopathology) of two groups were all within the normal range. Two diets did not induce difference in the diversity of gut bacteria. However, Firmicutes were significantly higher in rice diet group, while Bacteroidetes were enriched in pork diet group. Butyrate and the bacteria enzymes β-glucuronidase, β-glucosidase and nitroreductase in the feces were all drastically higher in pork diet group. This study indicates that different diets with similar calorie and nutritional composition could change the community structure but not the diversity of rat fecal microbiota.

Specific Strains of Lactic Acid Bacteria Differentially Modulate the Profile of Adipokines In Vitro

Obesity induces local/systemic inflammation accompanied by increases in macrophage infiltration into adipose tissue and production of inflammatory cytokines, chemokines, and hormones. Previous studies have shown that probiotics could improve the intestinal dysbiosis induced by metabolic diseases such as obesity, diabetes, and metabolic syndrome. Microorganisms could (directly or indirectly) affect adipokine levels due to their capacity to induce translocation of several intestinal microbial antigens into systemic circulation, which could lead to metabolic endotoxemia or produce immunomodulation in different organs. The aim of the present study was to select non-inflammatory lactic acid bacteria (LAB) strains with the capacity to modulate adipokine secretion by the adipose tissue. We wish to elucidate the role of potential probiotic strains in the regulation of the cross talking between immune cells such as macrophages and adipose cells. Mouse macrophage cell line RAW 264.7 was used for evaluating the ability of 14 LAB strains to induce cytokine production. The LAB strains were chosen based on their previously studied beneficial properties in health. Then, in murine adipocyte culture and macrophage–adipocyte coculture, we determined the ability of these strains to induce cytokines and leptin secretion. Tumor necrosis factor alpha, interleukin 6 (IL-6), IL-10, monocyte chemoattractant protein-1, and leptin levels were measured in cell supernatants. We also performed the detection and quantification of leptin receptor (Ob-Rb) expression in macrophage cell lines stimulated by these LAB strains. Differential secretion profile of cytokines in macrophage cells induced by LAB strains was observed. Also, the levels of Ob-Rb expression diverged among different LAB strains. In LAB-stimulated coculture cells (adipocytes and macrophages), we observed differential production of leptin and cytokines. Furthermore, we detected lower production levels in single culture than cocultured cells. The principal component analysis showed an association between the four clusters of strains established according to their inflammatory profiles and leptin adipocyte production and leptin receptor expression in macrophages. We conclude that coculture is the most appropriate system for selecting strains with the ability to modulate adipokine secretion. The use of microorganisms with low and medium inflammatory properties and ability to modulate leptin levels could be a strategy for the treatment of some metabolic diseases associated with dysregulation of immune response.

A proliferative probiotic Bifidobacterium strain in the gut ameliorates progression of metabolic disorders via microbiota modulation and acetate elevation

The gut microbiota is an important contributor to the worldwide prevalence of metabolic syndrome (MS), which includes obesity and diabetes. The anti-MS effects exerted by Bifidobacterium animalis ssp. lactis GCL2505 (BlaG), a highly proliferative Bifidobacterium strain in the gut, and B. longum ssp. longum JCM1217^T (BloJ) were comparatively examined. BlaG treatment reduced visceral fat accumulation and improved glucose tolerance, whereas BloJ had no effect on these parameters. Gut microbial analysis revealed that BlaG exerted stronger effects on the overall bacterial structure of the gut microbiota than BloJ, including enrichment of the genus Bifidobacterium. The levels of acetate and glucagon-like peptide-1 were increased by BlaG treatment in both the gut and plasma, but not by BloJ treatment. Correlation analysis suggested that the elevation of gut acetate levels by BlaG treatment plays a pivotal role in the BlaG-induced anti-MS effects. These findings indicated that BlaG, a highly viable and proliferative probiotic, improves metabolic disorders by modulating gut microbiota, which results in the elevation of SCFAs, especially acetate.

Impact of the Consumption of Tea Polyphenols on Early Atherosclerotic Lesion Formation and Intestinal Bifidobacteria in High-Fat-Fed ApoE-/- Mice

There is an increasing interest in the effect of dietary polyphenols on the intestinal microbiota and the possible associations between this effect and the development of some cardiovascular diseases, such as atherosclerosis (AS). However, limited information is available on how these polyphenols affect the gut microbiota and AS development. This study was designed to evaluate the modulation of dietary tea polyphenols (TPs) on intestinal Bifidobacteria (IB) and its correlation with AS development in apolipoprotein E-deficient (ApoE^−/−) mice. Fifty C57BL/6 ApoE^−/− mice were randomized into one of the five treatment groups (n = 10/group): control group fed normal diet (CK); a group fed a high-fat diet (HFD); and the other three groups fed the same HFD supplemented with TPs in drinking water for 16 weeks. The total cholesterol and low-density lipoprotein cholesterol (LDL-C) were decreased significantly (P < 0.05) after TP interference. In addition, the TP diet also decreased the plaque area/lumen area (PA/LA) ratios (P < 0.01) in the TP diet group. Interestingly, copies of IB in the gut of ApoE^−/− mice were notably increased with TP interference. This increase was dose dependent (P < 0.01) and negatively correlated with the PA/LA ratio (P < 0.05). We conclude that TPs could promote the proliferation of the IB, which is partially responsible for the reduction of AS plaque induced by HFD.

CST, an Herbal Formula, Exerts Anti-Obesity Effects through Brain-Gut-Adipose Tissue Axis Modulation in High-Fat Diet Fed Mice

The brain, gut, and adipose tissue interact to control metabolic pathways, and impairment in the brain-gut-adipose axis can lead to metabolic disorders, including obesity. Chowiseungcheng-tang (CST), a herbal formulation, is frequently used to treat metabolic disorders. Here, we investigated the anti-obesity effect of CST and its link with brain-gut-adipose axis using C57BL/6J mice as a model. The animals were provided with a normal research diet (NRD) or high-fat diet (HFD) in absence or presence of CST or orlistat (ORL) for 12 weeks. CST had a significant anti-obesity effect on a number of vital metabolic and obesity-related parameters in HFD-fed mice. CST significantly decreased the expression levels of genes encoding obesity-promoting neuropeptides (agouti-related peptide, neuropeptide Y), and increased the mRNA levels of obesity-suppressing neuropeptides (proopiomelanocortin, cocaine-and amphetamine-regulated transcript) in the hypothalamus. CST also effectively decreased the expression level of gene encoding obesity-promoting adipokine (retinol-binding protein-4) and increased the mRNA level of obesity-suppressing adipokine (adiponectin) in visceral adipose tissue (VAT). Additionally, CST altered the gut microbial composition in HFD groups, a phenomenon strongly associated with key metabolic parameters, neuropeptides, and adipokines. Our findings reveal that the anti-obesity impact of CST is mediated through modulation of metabolism-related neuropeptides, adipokines, and gut microbial composition.

Interventions for preventing gestational diabetes mellitus: an overview of Cochrane Reviews

This is the protocol for a review and there is no abstract. The objectives are as follows:

To summarise the evidence from Cochrane systematic Reviews regarding the effects of interventions for preventing gestational diabetes mellitus.

Probiotic Lactobacillus gasseri SBT2055 improves glucose tolerance and reduces body weight gain in rats by stimulating energy expenditure

Probiotic Lactobacillus gasseri SBT2055 (LG2055) reduces postprandial TAG absorption and exerts anti-obesity effects in rats and humans; however, the underlying mechanisms are not fully understood. In the present study, we addressed the mechanistic insights of the anti-obesity activity of LG2055 by feeding Sprague–Dawley rats diets containing skimmed milk fermented or not by LG2055 for 4 weeks and by analysing energy expenditure, glucose tolerance, the levels of SCFA in the caecum and serum inflammatory markers. Rats fed the LG2055-containing diet demonstrated significantly higher carbohydrate oxidation in the dark cycle (active phase for rats) compared with the control group, which resulted in a significant increase in energy expenditure. LG2055 significantly reduced cumulative blood glucose levels (AUC) compared with the control diet after 3 weeks and increased the molar ratio of butyrate:total SCFA in the caecum after 4 weeks. Furthermore, the LG2055-supplemented diet significantly reduced the levels of serum amyloid P component – an indicator of the inflammatory process. In conclusion, our results demonstrate that, in addition to the inhibition of dietary TAG absorption reported previously, the intake of probiotic LG2055 enhanced energy expenditure via carbohydrate oxidation, improved glucose tolerance and attenuated inflammation, suggesting multiple additive and/or synergistic actions underlying the anti-obesity effects exerted by LG2055.

Effects of Selenium-Enriched Probiotics on Lipid Metabolism, Antioxidative Status, Histopathological Lesions, and Related Gene Expression in Mice Fed a High-Fat Diet

A total of 80 female albino mice were randomly allotted into five groups (n = 16) as follows: (A) normal control, (B) high-fat diet (HFD),; (C) HFD + probiotics (P), (D) HFD + sodium selenite (SS), and (E) HFD + selenium-enriched probiotics (SP). The selenium content of diets in groups A, B, C, D, and E was 0.05, 0.05, 0.05, 0.3, and 0.3 μg/g, respectively. The amount of probiotics contained in groups C and E was similar (Lactobacillus acidophilus 0.25 × 10(11)/mL and Saccharomyces cerevisiae 0.25 × 10(9)/mL colony-forming units (CFU)). The high-fat diet was composed of 15 % lard, 1 % cholesterol, 0.3 % cholic acid, and 83.7 % basal diet. At the end of the 4-week experiment, blood and liver samples were collected for the measurements of lipid metabolism, antioxidative status, histopathological lesions, and related gene expressions. The result shows that HFD significantly increased the body weights and liver damages compared to control, while P, SS, or SP supplementation attenuated the body weights and liver damages in mice. P, SS, or SP supplementation also significantly reversed the changes of alanine aminotransferase (AST), aspartate aminotransferase (ALT), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), total protein (TP), high-density lipoprotein (HDL), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalasa (CAT), and malondialdehyde (MDA) levels induced by HFD. Generally, adding P, SS, or SP up-regulated mRNA expression of carnitine palmitoyltransferase-I (CPT1), carnitine palmitoyltransferase II (CPT2), acetyl-CoA acetyltransferase II (ACAT2), acyl-coenzyme A oxidase (ACOX2), and peroxisome proliferator-activated receptor alpha (PPARα) and down-regulated mRNA expression of fatty acid synthase (FAS), lipoprotein lipase (LPL), peroxisome proliferator-activated receptor gamma (PPARγ), and sterol regulatory element-binding protein-1 (SREBP1) involved in lipid metabolism. Among the group, adding SP has a maximum effect in improving lipid metabolism, antioxidative status, histopathological lesions, and related gene expression in mice fed a HFD.

Anti-obesity effect of milk fermented by Lactobacillus plantarum NCDC 625 alone and in combination with herbs on high fat diet fed C57BL/6J mice

The effect of dietary supplementation of milk fermented with indigenous probiotic Lactobacillus plantarum (LP625) alone and in combination with herbs (Aloe vera and Gymnema sylvestre) was investigated on high fat diet (HFD, 60 kcal% fat) fed mice for 12 weeks. Administration of LP625 alone or in combination with both herbs lowered the final body weight, however, a significant difference was observed with LP625 supplemented Gymnema sylvestre only as compared to the HFD fed group (25.06±0.18 vs 27.29±0.72 g, P<0.05). Similarly, the epididymal fat mass, fasting blood glucose and serum insulin levels were significantly (P<0.05) decreased by all treatment groups. In addition, a protective effect against the rise in serum and liver triglycerides, and in liver total cholesterol levels was found with the consumption of LP625 alone or in combination with herbs. Furthermore, the HFD fed mice showed a remarkable increase in the epididymal fat cell size, whereas administration of LP625 alone or in combination with herbs exhibited a significant decrease in the size. Finally, a significant increase in the relative mRNA expression of thermogenic proteins, i.e. uncoupling protein-2 (UCP-2, 1.16±0.25 fold change, P<0.05) and a decrease in pro-inflammatory markers, such as tumour necrosis factor-α and interleukin-6 (1.55±0.18 and 3.10±0.58 fold change, respectively, P<0.05) were due to LP625 supplementation in the HFD fed group. This shows that LP625 alone or supplemented with herbs seems to protect against diet induced obesity by decreasing the body and epididymal fat weight through upregulation of UCP-2 expression and reduced expression of pro-inflammatory cytokines.

Effect of Bifidobacterium animalis ssp. lactis GCL2505 on visceral fat accumulation in healthy Japanese adults: a randomized controlled trial

Bifidobacterium animalis ssp. lactis GCL2505 (B. lactis GCL2505) is able to survive passage through the intestine and then proliferate, leading to an increase in the amount of gut bifidobacteria. In the present study, we evaluated the impact of B. lactis GCL2505 on abdominal visceral fat storage in overweight and mildly obese Japanese adults. This clinical study was a double-blind, randomized, placebo-controlled, parallel-group comparative trial performed for 12 weeks. Healthy Japanese subjects (N=137) with body mass indices ranging from 23 to 30 kg/m² consumed either fermented milk containing B. lactis GCL2505 or a placebo every day, and then visceral and subcutaneous abdominal fat areas were measured by computed tomography as the primary endpoints. The number of fecal bifidobacteria was also measured. Visceral fat area, but not subcutaneous fat area, was significantly reduced from baseline at 8 and 12 weeks in the GCL2505 group, compared with the placebo group. The total number of fecal bifidobacteria was significantly increased in the GCL2505 group. These results indicate that B. lactis GCL2505 reduces abdominal visceral fat, a key factor associated with metabolic disorders. This finding suggests that this probiotic strain can potentially serve as a specific functional food to achieve visceral fat reduction in overweight or mildly obese individuals.

The Intestinal Microbiota in Metabolic Disease

Gut bacteria exert beneficial and harmful effects in metabolic diseases as deduced from the comparison of germfree and conventional mice and from fecal transplantation studies. Compositional microbial changes in diseased subjects have been linked to adiposity, type 2 diabetes and dyslipidemia. Promotion of an increased expression of intestinal nutrient transporters or a modified lipid and bile acid metabolism by the intestinal microbiota could result in an increased nutrient absorption by the host. The degradation of dietary fiber and the subsequent fermentation of monosaccharides to short-chain fatty acids (SCFA) is one of the most controversially discussed mechanisms of how gut bacteria impact host physiology. Fibers reduce the energy density of the diet, and the resulting SCFA promote intestinal gluconeogenesis, incretin formation and subsequently satiety. However, SCFA also deliver energy to the host and support liponeogenesis. Thus far, there is little knowledge on bacterial species that promote or prevent metabolic disease. Clostridium ramosum and Enterococcus cloacae were demonstrated to promote obesity in gnotobiotic mouse models, whereas bifidobacteria and Akkermansia muciniphila were associated with favorable phenotypes in conventional mice, especially when oligofructose was fed. How diet modulates the gut microbiota towards a beneficial or harmful composition needs further research. Gnotobiotic animals are a valuable tool to elucidate mechanisms underlying diet–host–microbe interactions.