Bifidobacterium adolescentis protects from the development of nonalcoholic steatohepatitis in a mouse model

Isolation and characterization of antimicrobial peptides from Lactobacillus: Exploring mechanisms of action

The rise of antibiotic-resistant bacteria necessitates the development of novel antimicrobial agents. In this study, antimicrobial peptides (AMPs) were isolated from Lactobacillus sp., yielding Bioactive Peptide I (BAP I) and Bioactive Peptide III (BAP III). Purified via gel filtration chromatography (GFC), these peptides were characterized by MALDI-TOF MS and SDS-PAGE, which confirmed their molecular masses as 4168.14 Da and 8076.45 Da, respectively, and verified their high purity. Both peptides demonstrated potent antibacterial activity against Pseudomonas aeruginosa, Streptococcus sanguinis, Bacillus cereus, and Staphylococcus aureus, with BAP I exhibiting superior efficacy. This enhanced activity is likely due to its amphipathic structure and hydrophobic C-terminal region, which promote effective bacterial membrane disruption as evidenced by FE-SEM imaging. In addition to compromising membrane integrity, both BAP I and BAP III inhibited bacterial DNA polymerase activity, as shown by reduced PCR product formation. Complementary Circular Dichroism (CD) spectroscopy analysis indicated that peptide binding induced conformational changes in Taq polymerase, reducing its α-helical and β-sheet content while increasing the proportion of random coil structures-thus enhancing the enzyme's flexibility. Molecular docking and dynamics studies further revealed stable interactions between the peptides and the enzyme, suggesting a dual mechanism of action that targets both the bacterial membrane and DNA replication processes. Collectively, these findings highlight the significant potential of BAP I and BAP III as novel antimicrobial agents against multidrug-resistant infections. Future research should focus on evaluating their safety and clinical efficacy, as well as exploring their synergistic potential with existing antibiotics to advance these peptides as therapeutic alternatives.

Bifidobacterium adolescentis prevents diabetes-induced liver injury via pyroptosis attenuation

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), along with non-alcoholic steatohepatitis (NASH), lacks definitive therapy and typically remains asymptomatic until reaching advanced stages. Lipid metabolism and inflammation management using probiotics such as Bifidobacterium adolescentis is suggested to alleviate or suppress NAFLD development. Hence, this study aims to investigate the effects of Bifidobacterium adolescentis treatment on mitigating pyroptosis, an inflammatory cell death pathway, in the liver of rats with NAFLD induced by high-fat diet (HFD) and streptozotocin (STZ) administration.

METHODS

Forty 8-week adult male Sprague Dawley rats were divided into four groups. Bifidobacterium adolescentis was administered for 8 and 16 weeks at 4 × 1010 CFU/day to rats fed a high-fat diet (HFD). Subsequently, the mRNA expression levels of pyroptotic-related genes including Cas1, Cas3, Cas11, NLRP3, GSDMD, IL-1β, and NF-κB were quantified in liver tissue using quantitative polymerase chain reaction (qPCR). Histopathological alterations and stereological changes in liver structure, as well as lipid profile (FBG, TG, TC, HDL, LDL), and liver indices (ALT, AST, ALP, LDH), were also evaluated across the different groups.

RESULTS

Bifidobacterium adolescentis administration significantly reduced the expression levels of NF-κB and pyroptotic-related genes. Additionally, this probiotic effectively reversed the adverse effects of the high-fat diet (HFD) on liver volume, Kupffer cell numbers, and hepatocyte nuclei. Furthermore, it improved the lipid profile and liver indices of rats fed with the HFD.

CONCLUSION

This study demonstrates that B. adolescentis supplementation prevents diabetes-induced liver injury by attenuating pyroptosis. These findings suggest that Bifidobacterium adolescentis may be a promising therapeutic approach for managing NAFLD and its associated complications, primarily by modulating key genes associated with pyroptosis and inflammation in rats fed with a high-fat diet.

Bifidobacterium adolescentis-derived hypaphorine alleviates acetaminophen hepatotoxicity by promoting hepatic Cry1 expression

Acetaminophen (APAP)-induced liver injury (AILI) is a pressing public health concern. Although evidence suggests that Bifidobacterium adolescentis (B. adolescentis) can be used to treat liver disease, it is unclear if it can prevent AILI. In this report, we prove that B. adolescentis significantly attenuated AILI in mice, as demonstrated through biochemical analysis, histopathology, and enzyme-linked immunosorbent assays. Based on untargeted metabolomics and in vitro cultures, we found that B. adolescentis generates microbial metabolite hypaphorine. Functionally, hypaphorine inhibits the inflammatory response and hepatic oxidative stress to alleviate AILI in mice. Transcriptomic analysis indicates that Cry1 expression is increased in APAP-treated mice after hypaphorine treatment. Overexpression of Cry1 by its stabilizer KL001 effectively mitigates liver damage arising from oxidative stress in APAP-treated mice. Using the gene expression omnibus (GEO) database, we verified that Cry1 gene expression was also decreased in patients with APAP-induced acute liver failure. In conclusion, this study demonstrates that B. adolescentis inhibits APAP-induced liver injury by generating hypaphorine, which subsequently upregulates Cry1 to decrease inflammation and oxidative stress.

Gestational supplementation of Bifidobacterium, Lactobacillus, and Streptococcus thermophilus attenuates hepatic steatosis in offspring mice through promoting fatty acid β-oxidation

Currently, Bifidobacterium, Lactobacillus, and Streptococcus thermophilus (BLS) are widely recognized as the crucially beneficial bacteria in the gut. Many preclinical and clinical studies have shown their protective effects against non-alcoholic fatty liver disease (NAFLD). However, whether gestational BLS supplementation could alleviate NAFLD in the offspring is still unknown. Kunming mice were given a high-fat diet (HFD) for 4 weeks before mating. They received BLS supplementation by gavage during pregnancy. After weaning, offspring mice were fed with a regular diet up to 5 weeks old. Gestational BLS supplementation significantly increased the abundance of Actinobacteriota, Bifidobacterium, and Faecalibaculum in the gut of dams exposed to HFD. In offspring mice exposed to maternal HFD, maternal BLS intake significantly decreased the ratio of Firmicutes to Bacteroidetes as well as the relative abundance of Prevotella and Streptococcus, but increased the relative abundance of Parabacteroides. In offspring mice, maternal BLS supplementation significantly decreased the hepatic triglyceride content and mitigated hepatic steatosis. Furthermore, maternal BLS supplementation increased the glutathione content and reduced malondialdehyde content in the liver. In addition, mRNA and protein expression levels of key rate-limiting enzymes in mitochondrial β-oxidation (CPT1α, PPARα, and PGC1α) in the livers of offspring mice were significantly increased after gestational BLS supplementation. Thus, gestational BLS supplementation may ameliorate maternal HFD-induced steatosis and oxidative stress in the livers of offspring mice by modulating fatty acid β-oxidation.

Insights into the Anti-Adipogenic and Anti-Inflammatory Potentialities of Probiotics against Obesity

Functional foods with probiotics are safe and effective dietary supplements to improve overweight and obesity. Thus, altering the intestinal microflora may be an effective approach for controlling or preventing obesity. This review aims to summarize the experimental method used to study probiotics and obesity, and recent advances in probiotics against obesity. In particular, we focused on studies (in vitro and in vivo) that used probiotics to treat obesity and its associated comorbidities. Several in vitro and in vivo (animal and human clinical) studies conducted with different bacterial species/strains have reported that probiotics promote anti-obesity effects by suppressing the differentiation of pre-adipocytes through immune cell activation, maintaining the Th1/Th2 cytokine balance, altering the intestinal microbiota composition, reducing the lipid profile, and regulating energy metabolism. Most studies on probiotics and obesity have shown that probiotics are responsible for a notable reduction in weight gain and body mass index. It also increases the levels of anti-inflammatory adipokines and decreases those of pro-inflammatory adipokines in the blood, which are responsible for the regulation of glucose and fatty acid breakdown. Furthermore, probiotics effectively increase insulin sensitivity and decrease systemic inflammation. Taken together, the intestinal microbiota profile found in overweight individuals can be modified by probiotic supplementation which can create a promising environment for weight loss along enhancing levels of adiponectin and decreasing leptin, tumor necrosis factor (TNF)-α, interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, and transforming growth factor (TGF)-β on human health.

The Effects of Bifidobacterium Probiotic Supplementation on Blood Glucose: A Systematic Review and Meta-Analysis of Animal Models and Clinical Evidence

Probiotic supplementation is a potential therapeutic for metabolic diseases, including obesity, metabolic syndrome (MetS), and type 2 diabetes (T2D), but most studies deliver multiple species of bacteria in addition to prebiotics or oral pharmaceuticals. This may contribute to conflicting evidence in existing meta-analyses of probiotics in these populations and warrants a systematic review of the literature to assess the contribution of a single probiotic genus to better understand the contribution of individual probiotics to modulate blood glucose. We conducted a systematic review and meta-analysis of animal studies and human randomized controlled trials (RCTs) to assess the effects of Bifidobacterium (BF) probiotic supplementation on markers of glycemia. In a meta-analysis of 6 RCTs, BF supplementation had no effect on fasting blood glucose {FBG; mean difference [MD] = -1.99 mg/dL [95% confidence interval (CI): -4.84, 0.86], P = 0.13}, and there were no subgroup differences between subjects with elevated FBG concentrations and normoglycemia. However, BF supplementation reduced FBG concentrations in a meta-analysis comprised of studies utilizing animal models of obesity, MetS, or T2D [n = 16; MD = -36.11 mg/dL (CI: -49.04, -23.18), P < 0.0001]. Translational gaps from animal to human trials include paucity of research in female animals, BF supplementation in subjects that were normoglycemic, and lack of methodologic reporting regarding probiotic viability and stability. More research is necessary to assess the effects of BF supplementation in human subjects with elevated FBG concentrations. Overall, there was consistent evidence of the efficacy of BF probiotics to reduce elevated FBG concentrations in animal models but not clinical trials, suggesting that BF alone may have minimal effects on glycemic control, may be more effective when combined with multiple probiotic species, or may be more effective in conditions of hyperglycemia rather than elevated FBG concentrations.

Fructose: a modulator of intestinal barrier function and hepatic health?

PURPOSE

Consumption of fructose has repeatedly been discussed to be a key factor in the development of health disturbances such as hypertension, diabetes type 2, and non-alcoholic fatty liver disease. Despite intense research efforts, the question if and how high dietary fructose intake interferes with human health has not yet been fully answered.

RESULTS

Studies suggest that besides its insulin-independent metabolism dietary fructose may also impact intestinal homeostasis and barrier function. Indeed, it has been suggested by the results of human and animal as well as in vitro studies that fructose enriched diets may alter intestinal microbiota composition. Furthermore, studies have also shown that both acute and chronic intake of fructose may lead to an increased formation of nitric oxide and a loss of tight junction proteins in small intestinal tissue. These alterations have been related to an increased translocation of pathogen-associated molecular patterns (PAMPs) like bacterial endotoxin and an induction of dependent signaling cascades in the liver but also other tissues.

CONCLUSION

In the present narrative review, results of studies assessing the effects of fructose on intestinal barrier function and their impact on the development of health disturbances with a particular focus on the liver are summarized and discussed.

The Role of Next-Generation Probiotics in Obesity and Obesity-Associated Disorders: Current Knowledge and Future Perspectives

Obesity and obesity-associated disorders pose a major public health issue worldwide. Apart from conventional weight loss drugs, next-generation probiotics (NGPs) seem to be very promising as potential preventive and therapeutic agents against obesity. Candidate NGPs such as Akkermansia muciniphila, Faecalibacterium prausnitzii, Anaerobutyricum hallii, Bacteroides uniformis, Bacteroides coprocola, Parabacteroides distasonis, Parabacteroides goldsteinii, Hafnia alvei, Odoribacter laneus and Christensenella minuta have shown promise in preclinical models of obesity and obesity-associated disorders. Proposed mechanisms include the modulation of gut flora and amelioration of intestinal dysbiosis, improvement of intestinal barrier function, reduction in chronic low-grade inflammation and modulation of gut peptide secretion. Akkermansia muciniphila and Hafnia alvei have already been administered in overweight/obese patients with encouraging results. However, safety issues and strict regulations should be constantly implemented and updated. In this review, we aim to explore (1) current knowledge regarding NGPs; (2) their utility in obesity and obesity-associated disorders; (3) their safety profile; and (4) their therapeutic potential in individuals with overweight/obesity. More large-scale, multicentric and longitudinal studies are mandatory to explore their preventive and therapeutic potential against obesity and its related disorders.

Feeding of Hermetia illucens Larvae Meal Attenuates Hepatic Lipid Synthesis and Fatty Liver Development in Obese Zucker Rats

The present study tested the hypothesis that dietary insect meal from Hermetia illucens (HI) larvae attenuates the development of liver steatosis and hyperlipidemia in the obese Zucker rat. To test the hypothesis, a 4-week trial with male, obese Zucker rats (n = 30) and male, lean Zucker rats (n = 10) was performed. The obese rats were assigned to three obese groups (group O-C, group O-HI25, group O-HI50) of 10 rats each. The lean rats served as a lean control group (L-C). Group L-C and group O-C were fed a control diet with 20% casein as protein source, whereas 25% and 50% of the protein from casein was replaced with protein from HI larvae meal in the diets of group O-HI25 and O-HI50, respectively. The staining of liver sections with Oil red O revealed an excessive lipid accumulation in the liver of group O-C compared to group L-C, whereas liver lipid accumulation in group O-HI25 and O-HI50 was markedly reduced compared to group O-C. Hepatic concentrations of triglycerides, cholesterol, C14:0, C16:0, C16:1, C18:0, C18:1, the sum of total fatty acids and hepatic mRNA levels of several genes associated with lipid synthesis and plasma concentration of cholesterol were markedly higher in group O-C than in group L-C, but lower in group O-HI50 than in group O-C (p < 0.05). In conclusion, partial replacement of casein by HI larvae meal attenuates liver steatosis and dyslipidemia in obese Zucker rats. This suggests that HI larvae meal serves as a functional food protecting from obesity-induced metabolic disorders.

Just Drink a Glass of Water? Effects of Bicarbonate-Sulfate-Calcium-Magnesium Water on the Gut-Liver Axis

Background and Aim: Fonte Essenziale® water is a bicarbonate-sulfate-calcium-magnesium water, low in sodium, recognized by the Italian health care system in hydropinotherapy and hepatobiliary dyspepsia therapy. We wanted to explore its effects on the gut-liver axis and microbiota in non-alcoholic fatty liver disease patients. Patients and Methods: We considered enrollment for 70 patients, of which four were excluded. We finally enrolled 55 patients with ultrasound-documented steatosis (SPs+) and 11 patients without it (SPs-). They then drank 400 ml of water for 6 months in the morning on an empty stomach. Routine hematochemical and metabolic parameters, oxidative stress parameters, gastrointestinal hormone levels, and fecal parameters of the gut microbiota were evaluated at three different assessment times, at baseline (T0), after 6 months (T6), and after a further 6 months of water washout (T12). We lost, in follow-up, 4 (T6) and 22 (T12) patients. Results: Between T0-T6, we observed a significant Futuin A and Selenoprotein A decrease and a GLP-1 and PYY increase in SPs+ and the same for Futuin A and GLP-1 in SPs-. Effects were lost at T12. In SPs+, between T0-T12 and T6-12, a significant reduction in Blautia was observed; between T0-T12, a reduction of Collinsella unc. was observed; and between T0-T12 and T6-12, an increase in Subdoligranulum and Dorea was observed. None of the bacterial strains we analyzed varied significantly in the SPs- population. Conclusion: These results indicate beneficial effects of water on gastrointestinal hormones and hence on the gut-liver axis in the period in which subjects drank water both in SPs- and in SPs+.

Rubus chingii Hu. unripe fruits extract ameliorates carbon tetrachloride-induced liver fibrosis and improves the associated gut microbiota imbalance

BACKGROUND

The unripe fruits of Rubus chingii Hu. ("Fu-peng-zi" in Chinese) is a well-known herbal tonic in traditional Chinese medicine (TCM) for tonifying liver and kidney. However, little is known regarding its therapeutic efficacy against liver fibrosis and the underlying mechanism.

METHODS

The current research aims to explore the potential of Rubus chingii Hu. unripe fruits extract (RF) in the treatment of liver fibrosis and explore the underlying mechanism. RF was administered (450 and 900 mg·kg^- 1 of body weight per day) orally to male C57BL/6 mice with CCl₄-induced liver fibrosis for 3 weeks. The histopathological changes and fibrosis stage in liver tissue were assessed using hematoxylin and eosin (H&E) and Sirius red staining. The distribution of α-SMA and Col1A1 in the liver was analyzed to determine the hepatic stellate cells (HSCs) activation using immunohistochemistry and immunofluorescent analysis. Various biochemical markers in serum (ALT, AST) and liver (Hyp, IL1-β, IL6, TNF-α and MCP-1) were observed to assess the liver's injury, fibrosis, and inflammation. In liver tissue, fibrosis-associated proteins including α-SMA, TGF-β1, Smad2/3, p-Smad2/3, and Smad4 were detected through a Western blot assay. Pyrosequencing-based analysis of bacterial 16 S ribosomal RNA from variable regions V3-V4 of fecal samples characterized the gut microbiota. Spearman's rank correlation analysis was performed for the association between altered bacterial genera by RF and pharmacodynamics parameters.

RESULTS

Three weeks of RF treatment can significantly lower liver inflammatory levels, pathological abnormalities, and collagen fibrous deposition in mice with CCl₄-induced liver fibrosis. The expressions of α-SMA and Col1A1 were lowered by RF, while the expression levels of TGF-β/Smads signaling pathway-related proteins, including TGF-β1, p-Smad2/3, and Smad4, were dramatically decreased by RF. The RF treatment significantly increased or reduced 18 different bacterial species, restoring the CCl₄-induced gut microbiota imbalance to the normal group's levels. According to correlation analysis, the bacterial genera Bifidobacterium and Turicibacter were the most significant in restoring CCl₄-induced liver fibrosis.

CONCLUSIONS

RF can reduce liver damage and delay the onset of liver fibrosis through modulating TGF-β/Smads signaling pathway. Furthermore, RF's anti-liver fibrosis effect was related to balancing the gut microbial community, partly attained by increasing Bifidobacterium and Turicibacter in liver fibrosis.

Feeding of cuticles from Tenebrio molitor larvae modulates the gut microbiota and attenuates hepatic steatosis in obese Zucker rats

Insect biomass obtained from large-scale mass-rearing of insect larvae has gained considerable attention in recent years as an alternative and sustainable source of food and feed. A byproduct from mass-rearing of insect larvae is the shed cuticles - the most external components of insects which are a relevant source of the polysaccharide chitin. While it has been shown that chitin modulates the gut microbiota and ameliorates lipid metabolic disorders in obese rodent models, feeding studies dealing with isolated insects' cuticles are completely lacking. Thus, the present study tested the hypothesis that dietary insects' cuticles modulate the gut microbiome and improve hepatic lipid metabolism in obese Zucker rats. To test this hypothesis, three groups of obese Zucker rats were fed a nutrient-adequate, semisynthetic basal diet which was supplemented with either 0% (group O), 1.5% (group O1.5) or 3.0% (group O3.0) Tenebrio molitor cuticles at the expense of cellulose. Oil red O-stained liver sections showed a marked lipid accumulation, but lipid accumulation was clearly less in group O3.0 than in groups O and O1.5. In line with this, hepatic lipid concentrations were 30% lower in group O3.0 than in group O (p < 0.05). No differences were observed across the obese groups regarding liver concentrations of methionine, S-adenosylmethionine and homocysteine. Analysis of cecal microbial community at the family level revealed that the relative abundances of Bifidobacteriaceae, Coriobacteriaceae Erysipelotrichaceae, Lactobacillaceae, Prevotellaceae, Sutterellaceae, unknown Deltaproteobacteria and unknown Firmicutes were higher and those of Anaeroplasmataceae, Desulfovibrionaceae, Eubacteriaceae, Ruminococcaceae, Saccharibacteria and unknown Clostridiales were lower in group O3.0 compared to group O (p < 0.05). Cecal digesta concentrations of total short-chain fatty acids, acetate and butyrate were higher in group O3.0 than in group O (p < 0.05). Targeted plasma metabolomics revealed 53 metabolites differing between groups, amongst which two indole metabolites, indole-3-propionic acid and 3-indoxylsulfate, were markedly elevated in group O3.0 compared to groups O1.5 and O. Regarding that increased abundances of bacteria of the Actinobacteria phylum and Lactobacillaceae family in the gut have been reported to be associated with antisteatotic, hepatoprotective and antiinflammatory effects, the pronounced increases of Bifidobacteriaceae and Coriobacteriaceae (both Actinobacteria), and of Lactobacillaceae in group O3.0 might have contributed to the amelioration of fatty liver.

Assessment of Two Potential Probiotic Strains As Anti-Obesity Supplements Under High-Fat Feeding Conditions

Obesity is one of the chronic diseases that increase annually and cause cardiovascular disease, which is the main cause of death worldwide. So, this study aims to evaluate the role of the two potential probiotics: Lactiplantibacillus plantarum Pro1 and Lacticaseibacillus rhamnosus Pro2, isolated from the fermented milk and corn silage as anti-obesity supplements. Seventy-five male BALB/c mice were distributed to five groups (control, obesity, obesity plus L. plantarum (OLP), obesity plus L. rhamnosus (OLR) and obesity plus mixture of two strains (OM)). The body weight, lipid profile, histopathology and enzymes of liver were assessed. RT-PCR was used to determine the expression of CYP7A1, ALTG4, TNFα and ROR genes.The findings show that the obesity group recorded the significant highest value of the body weight, TC, TG, LDL, AST and ALT, while OLP group recorded the significant lowest value. Liver tissue of obesity group has necrosis and fatty changes, while the OLP group was related to the control group. The findings of RT-PCR show non-significant differences between the control group and the OLP group, with significant differences between the control group and the set groups in expression of CYP7A1, ALTG4, TNFα and ROR genes. L. plantarum Pro1 reduced the expression of inflammation genes (TNFα and ROR), and increase the expression of the lipid metabolism genes (CYP7A1, ALTG4) to reduce the inflammatory effects of obesity in the liver, and decrease the cholesterol level in serum. Therefore, L. plantarum Pro1 is useful as anti-obesity supplements and an eliminator of the relevant diseases.

Engineered Probiotic and Prebiotic Nutraceutical Supplementations in Combating Non-communicable Disorders: A Review

Nutritional supplementations are a form of nutrition sources that may help in improving the health complexities of a person throughout his or her life span. Being also categorized as food supplementations, nutraceuticals are products that are extracted from edible sources with medical benefits as well as primary nutritional values. Nutraceuticals can be considered as functional foods. There are evidences that nutraceutical supplementations can alter the commensal gut microbiota and help to prevent or fight against chronic non-communicable degenerative diseases in adults, including neurological disorders (Autism Spectrum Disorder [ASD], Parkinson's disease [PD], Multiple sclerosis [MS]) and metabolic disorders (Type-II diabetes, obesity and non-alcoholic fatty liver disease). They can even lessen the complexities of preterm babies like extra-uterine growth restriction, necrotizing enterocolitis, infant eczema and allergy (during pregnancy) as well as bronchopulmonary dysplasia. Molecular perception of inflammatory and apoptotic modulators regulating the pathogenesis of these health risks, their control and management by probiotics and prebiotics could further emphasize the scientific overview of their utility. In this study, the pivotal role of nutraceutical supplementations in regulating or modulating molecular pathways in the above non-communicable diseases is briefly described. This work also gives an overall introduction of the sophisticated genome-editing techniques and advanced delivery systems in therapeutic activities applicable under these health risks.

Bifidobacterium bifidum Shows More Diversified Ways of Relieving Non-Alcoholic Fatty Liver Compared with Bifidobacterium adolescentis

The occurrence of non-alcoholic fatty liver disease (NAFLD) is closely related to intestinal microbiota disturbance, and probiotics has become a new strategy to assist in alleviating NAFLD. In order to investigate the effect of Bifidobacterium on NAFLD and the possible pathway, a NAFLD model was established by using a high-fat diet (HFD) for 18 weeks. Fourteen strains of Bifidobacterium were selected (seven Bifidobacterium adolescentis and seven Bifidobacterium bifidum) for intervention. The effects of different bifidobacteria on NAFLD were evaluated from liver cell injury, liver fat deposition, liver inflammatory state and liver histopathology, and were taken as entry points to explore the mitigation approaches of bifidobacteria through energy intake, lipid metabolism, glucose metabolism and intestinal permeability. The results showed that Bifidobacterium exerts species-specific effects on NAFLD. B. bifidum exerted these effects mainly through regulating the intestinal microbiota, increasing the relative abundance of Faecalibaculum and Lactobacillus, decreasing the relative abundance of Tyzzerella, Escherichia-Shigella, Intestinimonas, Osillibacter and Ruminiclostridium, and further increasing the contents of propionic acid and butyric acid, regulating lipid metabolism and intestinal permeability, and ultimately inhibiting liver inflammation and fat accumulation to alleviate NAFLD. B. adolescentis exerted its effects mainly through changing the intestinal microbiota, increasing the content of propionic acid, regulating lipid metabolism and ultimately inhibiting liver inflammation to alleviate NAFLD.

Probiotics and obesity associated disease: an extended view beyond traditional strains

Interaction between intestinal microbiota and obesity is becoming abundantly according to current many scientific investigations. In this article, probiotic therapy was offered as the promising strategy of metabolic disorders control through the recovery of microbiota composition and health maintenance with the help of impact on the abovementioned mechanisms. First, this therapy is safe, with minimal side effects, well-tolerated, and appropriate for long-term use. Second, it can improve body mass, glucose, and fat metabolism, increase insulin sensitivity, and decrease systemic chronic inflammation. In conclusion, the restorative role of gut microbiota on metabolic disorders and associated diseases could open new ways in the treatment of obesity, insulin resistance, and type 2 diabetes.

Enhanced Storage of Anaerobic Bacteria through Polymeric Encapsulation

Live microbes such as lactobacilli have long been used as probiotic supplements and, more recently, have been explored as live biotherapeutic products with the potential to treat a range of conditions. Among these microbes is a category of anaerobes that possess therapeutic potential while exhibiting unique oxygen sensitivity and thus requiring careful considerations in the formulation and storage processes. Existing microbial formulation development has focused on facultative anaerobes with natural oxygen tolerance; a few strategies have been reported for anaerobes with demonstrated oxygen intolerance, warranting novel approaches toward addressing the challenges for these oxygen-sensitive anaerobes. Here, we develop a polymeric encapsulation system for the formulation and storage of Bifidobacterium adolescentis (B. adolescentis), a model anaerobe that loses viability in aerobic incubation at 37 °C within 1 day. We discover that this strain remains viable under aerobic conditions for 14 days at 4 °C, enabling formulation development such as solution casting and air drying in an aerobic environment. Next, through a systematic selection of polymer encapsulants and excipients, we show that encapsulation with poly(vinyl alcohol) (PVA) acts as an oxygen barrier and facilitates long-term storage of B. adolescentis, which is partially attributed to reduced generation of reactive oxygen species. Lastly, PVA-based formulations can produce oral capsule-loaded films and edible gummy bears, demonstrating its compatibility with both pharmaceutical and food dosage forms.

Human Milk Oligosaccharides Modulate Fecal Microbiota and Are Safe for Use in Children With Overweight: A Randomized Controlled Trial

OBJECTIVES

Human milk oligosaccharides (HMOs) impact the intestinal microbiota by increasing beneficial bacteria in infants and adults, and are safe and well tolerated in these age groups. Effects on intestinal microbiota, safety, and digestive tolerance in children have not been, however, assessed. The aims of this trial were to evaluate if HMOs are able to specifically modulate the intestinal microbiota in children, and to assess safety and digestive tolerance.

METHODS

In this randomized, double-blinded, placebo-controlled trial, 75 children with overweight (including obesity) ages 6 to 12 years were randomized to receive 2'-fucosyllactose (2'FL), a mix of 2'FL and lacto-N-neotetraose (Mix), or a glucose placebo orally administrated once per day for 8 weeks.

RESULTS

The relative abundance of bifidobacteria increased significantly after 4 (P < 0.001) and 8 (P = 0.025) weeks of intervention in the 2'FL-group and after 4 weeks (P = 0.033) in the Mix-group, whereas no change was observed in the placebo group. Compared with placebo, the 2'FL-group had a significant increase in bifidobacteria abundance after 4 weeks (P < 0.001) and 8 weeks (P = 0.010) and the Mix-group showed a tendency to increased bifidobacteria abundance after 4 (P = 0.071) and 8 weeks (P = 0.071). Bifidobacterium adolescentis drove the bifidogenic effect in the 2 groups. Biochemical markers indicated no safety concerns, and the products did not induce digestive tolerance issues as assessed by Gastrointestinal Symptoms Rating Scale and Bristol Stool Form Scale.

CONCLUSIONS

Both 2'FL and the Mix beneficially modulate intestinal microbiota by increasing bifidobacteria. Furthermore, supplementation with either 2'FL alone or a Mix is safe and well tolerated in children.

Growth stimulation of Bifidobacterium from human colon using daikenchuto in an in vitro model of human intestinal microbiota

Daikenchuto (DKT) is a Japanese traditional herbal (Kampo) medicine containing ginseng, processed ginger, and Japanese or Chinese pepper. We aimed to determine how DKT affects human colonic microbiota. An in vitro microbiota model was established using fecal inocula collected from nine healthy volunteers, and each model was found to retain operational taxonomic units similar to the ones in the original human fecal samples. DKT was added to the in vitro microbiota model culture at a concentration of 0.5% by weight. Next-generation sequencing of bacterial 16S rRNA gene revealed a significant increase in the relative abundance of bacteria related to the Bifidobacterium genus in the model after incubation with DKT. In pure cultures, DKT significantly promoted the growth of Bifidobacterium adolescentis, but not that of Fusobacterium nucleatum or Escherichia coli. Additionally, in pure cultures, B. adolescentis transformed ginsenoside Rc to Rd, which was then probably utilized for its growth. Our study reveals the in vitro bifidogenic effect of DKT that likely contributes to its beneficial effects on the human colon.

Bifidobacterium adolescentis Alleviates Liver Steatosis and Steatohepatitis by Increasing Fibroblast Growth Factor 21 Sensitivity

The gut microbiota is a newly identified contributor to the development of non-alcoholic fatty liver disease (NAFLD). Previous studies of Bifidobacterium adolescentis (B. adolescentis), a species of Bifidobacterium that is common in the human intestinal tract, have demonstrated that it can alleviate liver steatosis and steatohepatitis. Fibroblast growth factor 21 (FGF21) has long been considered as a biomarker of NAFLD, and recent studies have shown the protective effect of FGF21 analogs on NAFLD. We wondered whether B. adolescentis treatment would alleviate NAFLD via the interaction with FGF21. To this end, male C57BL/6J mice on a choline-deficient high-fat diet (CDHFD) were treated with drinking water supplemented with B. adolescentis for 8 weeks, followed by the acute administration of recombinant mouse FGF21 protein (rmFGF21) to conduct the FGF21 response test. Consistent with previous studies, B. adolescentis supplementation reversed the CDHFD-induced liver steatosis and steatohepatitis. This was evaluated on the NAFLD activity score (NAS), reduced liver enzymes, and lipid accumulation. Further studies demonstrated that B. adolescentis supplementation preserved the gut barrier, reduced the gut microbiota-derived lipopolysaccharide (LPS), and inhibited the hepatic TLR4/NF-κB pathway. This was accompanied by the elevated expressions of the receptors of FGF21, fibroblast growth factor receptor 1 (FGFR1) and β-klotho (KLB), in the liver and the decreased expression of FGF21. The results of FGF21 response test showed that B. adolescentis supplementation alleviated the CDHFD-induced FGF21 resistance. In vivo experiments suggested that LPS could suppress the expression of FGF21 and KLB in a dose-dependent manner. Collectively, this study showed that B. adolescentis supplementation could alleviate NAFLD by increasing FGF21 sensitivity.

B. adolescentis ameliorates chronic colitis by regulating Treg/Th2 response and gut microbiota remodeling

Inflammatory bowel disease (IBD) is defined as an immune dysregulation disease with poor prognosis. Various therapies based on gut microbe modulation have been proposed. In this study, we aim to explore the therapeutic effect of B. adolescentis on IBD, as well as the immune and microecology mechanism of B. adolescentis in IBD. The fecal level of B. adolescentis was decreased in the IBD patients compared with the normal people in our cohort and the GMrepo database. To further clarify the role of B. adolescentis in IBD, we induced chronic colitis with three cycles of dextran sulfate sodium (DSS). We found B. adolescentis gavage exhibited protective effects as evidenced by the significantly decreased diarrhea score, spleen weight, and increased colon length. Accordingly, the cumulative histological grading was decreased in the B. adolescentis administration group. In addition, tight junction protein and mucin family were enhanced after B. adolescentis treatment. Furthermore, distinct effects were found with decreased pro-inflammatory cytokines such as TNF-α, IL-6, IL-1β, IL-18, IL-22, IL-9 and increased anti-inflammatory cytokines IL-10, IL-4, IL-5. Importantly, the colon lamina propria in the B. adolescentis group consisted of more Treg and Th2 cells, which inhibited extreme gut inflammation. Additionally, 16srRNA sequencing showed an evident increase in the B:F ratio in the B. adolescentis group. In particular, B. adolescentis application inhibited the excessive growth of Akkermansia and Escherichia-Shigella in genus level. In conclusion, B. adolescentis refined the DSS-induced chronic colitis by stimulating protective Treg/Th2 response and gut microbiota remodeling. B. adolescentis regularly treatment might improve the therapeutic effects for inflammatory bowel disease.

Bifidobacterium adolescentis supplementation attenuates fracture-induced systemic sequelae

The gut microbiota is an important contributor to both health and disease. While previous studies have reported on the beneficial influences of the gut microbiota and probiotic supplementation on bone health, their role in recovery from skeletal injury and resultant systemic sequelae remains unexplored. This study aimed to determine the extent to which probiotics could modulate bone repair by dampening fracture-induced systemic inflammation. Our findings demonstrate that femur fracture induced an increase in gut permeability lasting up to 7 days after trauma before returning to basal levels. Strikingly, dietary supplementation with Bifidobacterium adolescentis augmented the tightening of the intestinal barrier, dampened the systemic inflammatory response to fracture, accelerated fracture callus cartilage remodeling, and elicited enhanced protection of the intact skeleton following fracture. Together, these data outline a mechanism whereby dietary supplementation with beneficial bacteria can be therapeutically targeted to prevent the systemic pathologies induced by femur fracture.

Study on the additive protective effect of PGLYRP3 and Bifidobacterium adolescentis Reuter 1963 on severity of DSS-induced colitis in Pglyrp3 knockout (Pglyrp3 -/-) and wild-type (WT) mice

BACKGROUND AND AIMS

Pglyrp3 is a bactericidal innate immunity protein known to sustain the habitual gut microbiome and protect against experimental colitis. Intestinal inflammation and metaflammation are commonly associated with a marked reduction of commensal bifidobacteria. Whether Pglyrp3 and bifidobacteria interact synergistically or additively to alleviate metaflammation is unknown. We investigated the extent to which Pglyrp3 and bifidobacteria regulate metaflammation and gut bacterial dysbiosis in DSS-induced mouse models of intestinal inflammation.

MATERIAL & METHODS

8-10 weeks old male mice were used. In both WT and Pglyrp3 -/- experiments, the mice were randomly divided into three groups of 16 mice per group: (1) a control group receiving sterile tap water, (2) an experimental group receiving sterile tap water supplemented with only 5% DSS, and (3) an experimental group receiving sterile tap water supplemented with 5% DSS and 1 × 10⁹ CFU/ml of Bifidobacterium adolescentis (B.a.) for 7 days. Wild-type (WT) littermates of the respective gene (i.e. Pglyrp3) were used as controls throughout the study. Clinical signs of general health and inflammation were monitored daily. Faecal pellet samples were analysed by qRT-PCR for microbial composition. Histology of relevant organs was carried out on day 8. Metabolic parameters and liver inflammation were determined in serum samples.

RESULTS

Intestinal inflammation in mice of group 2 were significantly increased compared to those of control group 1. There was a significant difference in mean scores for inflammation severity between DSS-treated WT and DSS-treated Pglyrp3 -/- mice. Buildup of key serum metabolic markers (cholesterol, triglyceride and glucose) was set off by colonic inflammation. qRT-PCR quantification showed that DSS significantly decreased the Clostridium coccoides and Bifidobacterium cell counts while increasing those of Bacteroides group in both WT and Pglyrp3 -/- mice. These manifestations of DSS-induced dysbiosis were significantly attenuated by feeding B.a. Both the local and systemic ill-being of the mice alleviated when they received B.a.

DISCUSSION

This study shows that Pglyrp3 facilitates recognition of bifidobacterial cell wall-derived peptidoglycan, thus leading additively to a reduction of metaflammation through an increase in the number of bifidobacteria, which were able to mitigate intestinal immunopathology in the context of Pglyrp3 blockade.

Lactobacillus acidophilus Antimicrobial Peptide Is Antagonistic to Aeromonas hydrophila

We identified an antimicrobial peptide (AMP) from Lactobacillus acidophilus that was antagonistic to Aeromonas hydrophila. In vitro studies such as well-diffusion and field trials revealed that the AMP was active against A. hydrophila. The field trials of AMP using A. hydrophila-infected Channa striatus with a mannone oligosaccharide (MOS) prebiotic, A. hydrophila antigens, A. hydrophila-infected fish serum, L. acidophilus, and Lactobacillus cell free-supernatant (LABS-CFS) on an indicator organism further revealed that the antimicrobial agent could protect C. striatus. Other than the AMP, none of the above were able to eliminate the infectious agent A. hydrophila, and were only able to delay the death rate for 3-4 days. Thus, we conclude that the AMP is antagonistic to A. hydrophila and may be used for treatment of A. hydrophila infections. Subsequent L. acidophilus whole-genome sequence analyses enabled an understanding of the (probable) gene arrangement and its location on the chromosome. This information may be useful in the generation of recombinant peptides to produce larger quantities for treatment.

Effects of a high-fat-diet supplemented with probiotics and ω3-fatty acids on appetite regulatory neuropeptides and neurotransmitters in a pig model

The pig is a valuable animal model to study obesity in humans due to the physiological similarity between humans and pigs in terms of digestive and associated metabolic processes. The dietary use of vegetal protein, probiotics and omega-3 fatty acids is recommended to control weight gain and to fight obesity-associated metabolic disorders. Likewise, there are recent reports on their beneficial effects on brain functions. The hypothalamus is the central part of the brain that regulates food intake by means of the production of food intake-regulatory hypothalamic neuropeptides, as neuropeptide Y (NPY), orexin A and pro-opiomelanocortin (POMC), and neurotransmitters, such as dopamine and serotonin. Other mesolimbic areas, such as the hippocampus, are also involved in the control of food intake. In this study, the effect of a high fat diet (HFD) alone or supplemented with these additives on brain neuropeptides and neurotransmitters was assessed in forty-three young pigs fed for 10 weeks with a control diet (T1), a high fat diet (HFD, T2), and HFD with vegetal protein supplemented with Bifidobacterium breve CECT8242 alone (T3) or in combination with omega-3 fatty acids (T4). A HFD provoked changes in regulatory neuropeptides and 3,4-dihydroxyphenylacetic acid (DOPAC) in the hypothalamus and alterations mostly in the dopaminergic system in the ventral hippocampus. Supplementation of the HFD with B. breve CECT8242, especially in combination with omega-3 fatty acids, was able to partially reverse the effects of HFD. Correlations between productive and neurochemical parameters supported these findings. These results confirm that pigs are an appropriate animal model alternative to rodents for the study of the effects of HFD on weight gain and obesity. Furthermore, they indicate the potential benefits of probiotics and omega-3 fatty acids on brain function.

Bifidobacterium adolescentis and Lactobacillus rhamnosus alleviate non-alcoholic fatty liver disease induced by a high-fat, high-cholesterol diet through modulation of different gut microbiota-dependent pathways

The incidence of non-alcoholic fatty liver disease (NAFLD) has increased year on year, and the increasing appreciation of the importance of gut microbiota provides novel therapeutic avenues for the treatment of NAFLD. To explore the similarities and differences between lactic acid bacteria (LAB) known to alleviate NAFLD, we selected three strains of Bifidobacterium adolescentis and three strains of Lactobacillus rhamnosus to administer to C57BL/6J mice on a high-fat, high-cholesterol diet (HFHCD) for 23 weeks. Subsequently, the effects of the LAB were evaluated through various measures. The six LAB strains were found to have varying degrees of efficacy in the prevention of NAFLD. We found that there were interspecific and intraspecific differences in the beneficial effects, mainly with respect to energy metabolism, lipid metabolism and short-chain fatty acid concentration. Three strains of B. adolescentis and one strain of L. rhamnosus were found to relieve NAFLD by increasing the concentration of short-chain fatty acids in the intestine of NAFLD mice. The other two strains of L. rhamnosus, LGG and L10-1, relieved NAFLD through different ways, LGG modulated energy metabolism and lipid metabolism, and L10-1 reduced liver inflammation. Examination of gut microbiota indicated that the six LAB strains could block the HFHCD-induced elevation of Firmicutes/Bacteroidetes and alter the dominant species within the gut. These results suggest that B. adolescentis and L. rhamnosus can inhibit the development of NAFLD by regulating gut microbiota, and their use is thus a promising therapeutic strategy.

Probiotic mediated NF-κB regulation for prospective management of type 2 diabetes

Diabetes and other lifestyle disorders have been recognized as the leading cause of morbidity and mortality globally. Nuclear factor kappa B (NF-κB) is a major factor involved in the early pathobiology of diabetes and studies reveal that hyperglycemic conditions in body leads to NF-κB mediated activation of several cytokines, chemokines and inflammatory molecules. NF-κB family comprises of certain DNA-binding protein factors that elicit the transcription of pro-inflammatory molecules. Various studies have identified NF-κB as a promising target for diabetic management. Probiotics have been proposed as bio-therapeutic agents for treatment of inflammatory disorders and many other chronic clinical stages. The precise mechanisms by which probiotics acts is yet to be fully understood, however research findings have indicated their role in NF-κB modulation. The current review highlights NF-κB as a bio-therapeutic target for probable management of type 2 diabetes through probiotic intervention.

Probiotics: How Effective Are They in the Fight against Obesity?

Obesity has been associated with structural and functional changes in the gut microbiota. The abundance in, and diversity of, certain bacteria may favor energy harvest and metabolic pathways leading to obesity. Therefore, gut microbiota has become a potential target that can be manipulated to obtain optimal health. Probiotics have been shown to influence the composition of the gut microbiota, improve gut integrity, and restore the microbial shifts characteristic of obesity. Based on physical and biochemical parameters, metabolic and inflammatory markers, and alterations in gut microbe diversity, animal studies revealed beneficial results in obese models whereas the results in humans are sparse and inconsistent. Thus, the purpose of this review is to present evidence from animal studies and human clinical trials demonstrating the effects of various probiotic strains and their potential efficacy in improving obesity and associated metabolic dysfunctions. Furthermore, the review discusses current gaps in our understanding of how probiotics modulate gut microflora to protect against obesity. Finally, we propose future studies and methodological approaches that may shed light on the challenges facing the scientific community in deciphering the host–bacteria interaction in obesity.

Genetically Obese Human Gut Microbiota Induces Liver Steatosis in Germ-Free Mice Fed on Normal Diet

Dysbiotic gut microbiota contributes to genetically obese phenotype in human. However, the effect of genetic obesity-associated gut microbiota on host hepatic metabolic deteriorations remains largely unknown. Gut microbiota from a genetically obese human donor before and after a dietary weight loss program was transplanted into germ-free C57BL/6J male mice, grouped as PreM and PostM groups, respectively. The gut microbiome, liver pathology and transcriptome response in the gnotobiotic mice were evaluated. After being fed on normal chow diet for 4 weeks, PreM group developed liver macrovesicular steatosis accompanied with higher concentrations of hepatic triglyceride and cholesterol, while PostM group exhibited normal hepatic physiology. The gut microbiota in PreM and PostM groups was significantly different from each other and was more resembling with their respective donor. RNA-sequencing revealed that, in comparison with PostM group, PreM group showed a foregoing pro-steatotic transcriptional response in liver featuring by the repression of lipid beta-oxidation and the activation of lipid absorption and cholesterol uptake before the pathology of liver steatosis. Moreover, peroxisome proliferator-activated receptor alpha (PPARα), which was repressed in PreM group, may act as crucial regulator of the hepatic transcriptional profile of lipid metabolism between two groups. Our results show that gut microbiota from a genetically obese human promotes the onset of liver steatosis by impacting hepatic transcriptional profile of lipid metabolism in mice. This adds new evidence that gut microbiota may play a causative role in the development of non-alcoholic fatty liver disease.

Probiotic Bifidobacterium strains and galactooligosaccharides improve intestinal barrier function in obese adults but show no synergism when used together as synbiotics

BACKGROUND

One way to improve both the ecological performance and functionality of probiotic bacteria is by combining them with a prebiotic in the form of a synbiotic. However, the degree to which such synbiotic formulations improve probiotic strain functionality in humans has not been tested systematically. Our goal was to use a randomized, double-blind, placebo-controlled, parallel-arm clinical trial in obese humans to compare the ecological and physiological impact of the prebiotic galactooligosaccharides (GOS) and the probiotic strains Bifidobacterium adolescentis IVS-1 (autochthonous and selected via in vivo selection) and Bifidobacterium lactis BB-12 (commercial probiotic allochthonous to the human gut) when used on their own or as synbiotic combinations. After 3 weeks of consumption, strain-specific quantitative real-time PCR and 16S rRNA gene sequencing were performed on fecal samples to assess changes in the microbiota. Intestinal permeability was determined by measuring sugar recovery in urine by GC after consumption of a sugar mixture. Serum-based endotoxin exposure was also assessed.

RESULTS

IVS-1 reached significantly higher cell numbers in fecal samples than BB-12 (P < 0.01) and, remarkably, its administration induced an increase in total bifidobacteria that was comparable to that of GOS. Although GOS showed a clear bifidogenic effect on the resident gut microbiota, both probiotic strains showed only a non-significant trend of higher fecal cell numbers when administered with GOS. Post-aspirin sucralose:lactulose ratios were reduced in groups IVS-1 (P = 0.050), IVS-1 + GOS (P = 0.022), and GOS (P = 0.010), while sucralose excretion was reduced with BB-12 (P = 0.002) and GOS (P = 0.020), indicating improvements in colonic permeability but no synergistic effects. No changes in markers of endotoxemia were observed.

CONCLUSION

This study demonstrated that "autochthony" of the probiotic strain has a larger effect on ecological performance than the provision of a prebiotic substrate, likely due to competitive interactions with members of the resident microbiota. Although the synbiotic combinations tested in this study did not demonstrate functional synergism, our findings clearly showed that the pro- and prebiotic components by themselves improved markers of colonic permeability, providing a rational for their use in pathologies with an underlying leakiness of the gut.

Lack of liver steatosis in germ-free mice following hypercaloric diets

PURPOSE

Experimental liver steatosis induced by overfeeding is associated with enhanced gut permeability and endotoxin translocation to the liver. We examined the role of the gut microbiota for steatosis formation by performing the feeding experiments in mice raised under conventional and germ-free (GF) housing.

METHODS

Adult wild-type and GF mice were fed a Western-style diet (WSD) or a control diet (CD), the latter combined with liquid fructose supplementation (F) or not, for 8 weeks. Markers of liver steatosis and gut permeability were measured after intervention.

RESULTS

Mice fed a WSD increased body weight compared to those fed a CD (p < 0.01) under conventional, but not under GF conditions. Increased liver weight, liver-to-body-weight ratio and hepatic triglycerides observed in both the WSD and the CD + F groups, when compared with the CD group, were not apparent under GF conditions, whereas elevated plasma triglycerides were visible (p < 0.05). Wild-type mice fed a WSD or a CD + F, respectively, had thinner adherent mucus layer compared to those fed a CD (p < 0.01), whereas GF mice had always a thin mucus layer independently of the diet. GF mice fed a CD showed increased plasma levels of FITC-dextran 4000 (1.9-fold, p < 0.05) and intestinal fatty acid-binding protein-2 (2.4-fold, p < 0.05) compared with wild-type mice.

CONCLUSIONS

GF housing results in an impaired weight gain and a lack of steatosis following a WSD. Also the fructose-induced steatosis, which is unrelated to body weight changes, is absent in GF mice. Thus, diet-induced experimental liver steatosis depends in multiple ways on intestinal bacteria.

The development of probiotics therapy to obesity: a therapy that has gained considerable momentum

Obesity is a growing epidemic worldwide. The most frequent cause leading to the development of obesity is an imbalance between energy intake and energy expenditure. The gut microbiota is an environmental factor involved in obesity and metabolic disorders which reveals that obese animal and human subjects present alterations in the composition of the gut microbiota compared to their lean counterparts. Furthermore, evidence has so far demonstrated that the gut microbiota, which influences whole-body metabolism, by affecting energy balance, but also inflammation and gut barrier function, integrates peripheral and central food intake regulatory signals, thereby altering body weight. At the same time, these data suggest that species of intestinal commensal bacteria may play either a pathogenic or a protective role in the development of obesity. Though still a relatively nascent field of research, evidence to date suggests that manipulating the gut microbiome may represent effective treatment for the prevention or management of obesity. Various studies have described the beneficial effects of specific bacteria on the characteristics of obesity. However, the available data in this field remain limited and the relevant scientific work has only recently begun. This review aims to summarize the notable advances and contributions in the field that may prove useful for identifying probiotics that target obesity and its related disorders.

Synbiotics Bifidobacterium infantis and milk oligosaccharides are effective in reversing cancer-prone nonalcoholic steatohepatitis using western diet-fed FXR knockout mouse models

Milk oligosaccharides (MO) selectively increase the growth of Bifidobacterium infantis (B. infantis). This study examines the effects of bovine MO and B. infantis in preventing nonalcoholic steatohepatitis (NASH) in Western diet (WD)-fed bile acid (BA) receptor FXR (farnesoid x receptor) knockout (KO) mice. WD-fed FXR KO mice have cancer-prone NASH and reduced B. infantis. MO and/or B. infantis supplementation improved their insulin sensitivity and reduced hepatic inflammation. Additionally, B. infantis, but not MO, decreased hepatic triglyceride and cholesterol. A combination of both further reduced hepatic cholesterol, the precursor of BAs. All three treatments modulated serum and hepatic BA profile. Moreover, B. infantis and MO decreased hepatic CYP7A1 and induced Sult2a1, Sult2a2, and Sult2a3 suggesting reduced BA synthesis and increased detoxification. Furthermore, B. infantis and MO increased ileal BA membrane receptor TGR5-regulated signaling. Together, via BA-regulated signaling, synbiotics B. infantis and MO have their unique and combined effects in reversing NASH.

Efficacy of Probiotics and Smectite in Rats with Non-Alcoholic Fatty Liver Disease

INTRODUCTION AND AIM

Today probiotics have been suggested as a treatment for the prevention of non-alcoholic fatty liver disease (NAFLD). Smectite is a natural silicate that binds to digestive mucous and has the ability to bind endo- and exotoxins. The present study was designed to determine whether probiotics plus smectite is superior to probiotic alone on the monosodium glutamate (MSG) induced NAFLD model in rats.

MATERIALS AND METHODS

We included 60 rats divided into 4 groups 15 animals in each. Rats of group I were intact. Newborns rats of groups II-IV were injected with MSG. The III (Symbiter) group received 2.5 ml/kg of multiprobiotic "Symbiter" containing concentrated biomass of 14 probiotic bacteria genera. The IV (Symbiter+Smectite) groups received "Symbiter Forte" combination of probiotic biomass with smectite gel (250 mg).

RESULTS

In both interventional groups reduction of total NAS score as compared to MSG-obesity was observed. Indeed similar values of steatosis score (0.93 ± 0.22 vs. 0.87 ± 0.16) in both treatment groups, we observed that lower total score for Symbiter+ Smectite are associated with more pronounced reduction of lobular inflammation (0.13 ± 0.09 vs. 0.33 ± 0.15) as compared to administration of probiotic alone. This data accompanied with significant reduction of IL-1 and restoration of IL-10 between these 2 groups.

CONCLUSIONS

Additional to alive probiotic administration of smectite gel due to his absorbent activity and mucus layer stabilization properties can impact on synergistic enhancement of single effect which manifested with reduction of lobular inflammation and at list partly steatohepatitis prevention.

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.

Emerging Trends in "Smart Probiotics": Functional Consideration for the Development of Novel Health and Industrial Applications

The link between gut microbiota and human health is well-recognized and described. This ultimate impact on the host has contributed to explain the mutual dependence between humans and their gut bacteria. Gut microbiota can be manipulated through passive or active strategies. The former includes diet, lifestyle, and environment, while the latter comprise antibiotics, pre- and probiotics. Historically, conventional probiotic strategies included a phylogenetically limited diversity of bacteria and some yeast strains. However, biotherapeutic strategies evolved in the last years with the advent of fecal microbiota transplant (FMT), successfully applied for treating CDI, IBD, and other diseases. Despite the positive outcomes, long-term effects resulting from the uncharacterized nature of FMT are not sufficiently studied. Thus, developing strategies to simulate the FMT, using characterized gut colonizers with identified phylogenetic diversity, may be a promising alternative. As the definition of probiotics states that the microorganism should have beneficial effects on the host, several bacterial species with proven efficacy have been considered next generation probiotics. Non-conventional candidate strains include Akkermansia muciniphila, Faecalibacterium prausnitzii, Bacteroides fragilis, and members of the Clostridia clusters IV, XIVa, and XVIII. However, viable intestinal delivery is one of the current challenges, due to their stringent survival conditions. In this review, we will cover current perspectives on the development and assessment of next generation probiotics and the approaches that industry and stakeholders must consider for a successful outcome.

Probiotics Supplemented with Omega-3 Fatty Acids are More Effective for Hepatic Steatosis Reduction in an Animal Model of Obesity

Today probiotics have been suggested as a treatment for the prevention of NAFLD. Omega-3 fatty acid supplementation may have beneficial effects in regulating hepatic lipid metabolism, adipose tissue function and inflammation. The present study was designed to determine whether probiotics plus omega-3 are superior to probiotics alone on the monosodium glutamate (MSG)-induced NAFLD model in rats. We included 60 rats divided into four groups, 15 animals in each. Rats of group I were intact. Newborn rats of groups II-IV were injected with MSG. The III (Symbiter) group received 2.5 ml/kg of multiprobiotic "Symbiter" containing concentrated biomass of 14 probiotic bacteria genera. The IV (Symbiter-Omega) groups received "Symbiter-Omega" combination of probiotic biomass supplemented with flax and wheat germ oil (250 mg of each, concentration of omega-3 fatty acids 1-5 %). In both interventional groups reduction in total NAS score was observed. Supplementation of alive probiotic mixture with omega-3 fatty acids lead to 20 % higher decrease in steatosis score (0.73 ± 0.11 vs 0.93 ± 0.22, p = 0.848) and reduction by 16.6 % of triglycerides content in liver as compared to probiotic alone. Our study demonstrated more pronounced reduction in hepatic steatosis and hepatic lipid accumulation after treatment with combination of alive probiotics and omega-3 as compared to probiotics alone.

Microbial Impact on Host Metabolism: Opportunities for Novel Treatments of Nutritional Disorders?

Malnutrition is the cause of major public health concerns worldwide. On the one hand, obesity and associated pathologies (also known as the metabolic syndrome) affect more than 10% of the world population. Such pathologies might arise from an elevated inflammatory tone. We have discovered that the inflammatory properties of high-fat diets were linked to the translocation of lipopolysaccharide (LPS). We proposed a mechanism associating the gut microbiota with the onset of insulin resistance and low-grade inflammation, a phenomenon that we called "metabolic endotoxemia." We and others have shown that bacteria as well as host-derived immune-related elements control microbial communities and eventually contribute to the phenotype observed during diet-induced obesity, diabetes, and metabolic inflammation. On the other hand, undernutrition is one of the leading causes of death in children. A diet poor in energy and/or nutrients causes incomplete development of the gut microbiota and may profoundly affect energy absorption, initiating stunted growth, edema, and diarrhea. In this review, we discuss how changes in microbiota composition are associated with obesity and undernutrition. We also highlight that opposite consequences exist in terms of energy absorption from the diet (obesity versus undernutrition), but interestingly the two situations share similar defects in term of diversity, functionality, and inflammatory potential.

Loss of lipopolysaccharide-binding protein attenuates the development of diet-induced non-alcoholic fatty liver disease in mice

BACKGROUND AND AIM

It has been suggested in several studies that an increased translocation of bacterial lipopolysaccharide (LPS) and, subsequently, an activation of toll-like receptor (TLR)-dependent signaling pathways in the liver may contribute to the development of non-alcoholic fatty liver disease.

METHODS

Eight-week-old lipopolysaccharide-binding protein (LBP)-/- and wild-type (WT) mice were pair fed either a liquid diet rich in fat, fructose, and cholesterol (Western-style diet [WSD]) or a control liquid diet for 8 weeks. Parameters of liver injury, markers of TLR-4-dependent signaling pathway, and glucose/lipid metabolism were determined.

RESULTS

Despite similar total caloric intake, weight gain, fasting blood glucose levels, and liver-to-bodyweight ratio, indices of liver damage determined by liver histology and transaminases were markedly lower in WSD-fed LBP-/- mice than in WSD-fed WT animals. In line with these findings, number of neutrophils, F4/80 positive cells, and plasminogen activator inhibitor 1 were only found to be significantly increased in livers of WSD-fed WT mice. While mRNA expressions of TLR-4 and myeloid differentiation primary response 88 were similar between WSD-fed groups, concentrations of inducible nitric oxide synthase protein and 4-hydroxynonenal protein adducts were significantly higher in livers of WSD-fed WT mice than in WSD-fed LBP-/- animals. Markers of lipid metabolism, for example, sterol regulatory element-binding protein 1c and fatty acid synthase per se, were significantly lower in livers of LBP-/- mice; however, mRNA expressions did not differ between controls and WSD-fed mice within the respective mouse strain.

CONCLUSION

Taken together, our results suggest that LBP is a critical factor in the development of non-alcoholic fatty liver disease in mice.

Treatment with alpha-galactosylceramide protects mice from early onset of nonalcoholic steatohepatitis: Role of intestinal barrier function

SCOPE

The role of invariant natural killer T cells in the development of nonalcoholic steatohepatitis (NASH) has not yet been fully understood. Here, the effect of the invariant natural killer T-cell activator alpha-galactosylceramide (αGalCer) on the development of nonalcoholic fatty liver disease and intestinal barrier function was assessed in a mouse model of early Western-style diet (WSD) induced NASH.

METHODS AND RESULTS

Female C57BL/6J mice were either fed a liquid control diet or a liquid fructose-enriched WSD for 6 wk while being treated three times weekly with αGalCer (2 μg intraperitoneal) or vehicle. Indices of liver damage, glucose metabolism, and intestinal permeability were measured. Treatment with αGalCer markedly suppressed hepatic fat accumulation and inflammation while not affecting fasting glucose. The protective effects of αGalCer were associated with a protection against the increased translocation of bacterial endotoxins and the decreased protein levels of tight junction proteins occludin and zonula occludens 1 found in vehicle-treated mice while being fed a WSD.

CONCLUSION

Taken together, our data suggest that the protective effects of αGalCer against the development of a diet-induced NASH in mice are associated with a protection against the increased translocation of intestinal bacterial endotoxins associated with the development of NASH.

Effect of prebiotics of Agave salmiana fed to healthy Wistar rats

BACKGROUND

Inulin and other fructans are synthesized and stored in mezcal agave (Agave salmiana). Fructans provide several health benefits and have excellent technological properties, but only few data report their physiological effect when added in the diet.

RESULTS

Here, we studied the physiological effects of fructans obtained from A. salmiana when added in the diet of Wistar rats. Results showed favorable changes on Wistar rats when the fructans was added to their diet, including the decrease of the pH in the feces and the increase of the number of lactic acid bacteria (CFU g^-1 ) (Lactobacillus spp. and Bifidobacterium spp.), even these changes were enhanced with the synbiotic diet (fructans plus B. animalis subsp. lactis). Synbiotic diet, developed changes in the reduction of cholesterol and triglycerides concentrations in serum, with statistical differences (P < 0.05). Histological analysis of colon sections showed that synbiotic diet promoted colon cells growth suggesting that fructans from A. salmiana confer beneficial health effects through gut microbiota modulation.

CONCLUSION

Our data underline the advantage of targeting the gut microbiota by colonic nutrients like specific structure of fructans from A. salmiana, with their beneficial effects. More studies are necessary to define the role of fructans to develop more solid therapeutic solutions in humans. © 2016 Society of Chemical Industry.

Precision medicine in alcoholic and nonalcoholic fatty liver disease via modulating the gut microbiota

Alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) represent a major health burden in industrialized countries. Although alcohol abuse and nutrition play a central role in disease pathogenesis, preclinical models support a contribution of the gut microbiota to ALD and NAFLD. This review describes changes in the intestinal microbiota compositions related to ALD and NAFLD. Findings from in vitro, animal, and human studies are used to explain how intestinal pathology contributes to disease progression. This review summarizes the effects of untargeted microbiome modifications using antibiotics and probiotics on liver disease in animals and humans. While both affect humoral inflammation, regression of advanced liver disease or mortality has not been demonstrated. This review further describes products secreted by Lactobacillus- and microbiota-derived metabolites, such as fatty acids and antioxidants, that could be used for precision medicine in the treatment of liver disease. A better understanding of host-microbial interactions is allowing discovery of novel therapeutic targets in the gut microbiota, enabling new treatment options that restore the intestinal ecosystem precisely and influence liver disease. The modulation options of the gut microbiota and precision medicine employing the gut microbiota presented in this review have excellent prospects to improve treatment of liver disease.

Genome Structure of the Symbiont Bifidobacterium pseudocatenulatum CECT 7765 and Gene Expression Profiling in Response to Lactulose-Derived Oligosaccharides

Bifidobacterium pseudocatenulatum CECT 7765 was isolated from stools of a breast-fed infant. Although, this strain is generally considered an adult-type bifidobacterial species, it has also been shown to have pre-clinical efficacy in obesity models. In order to understand the molecular basis of its adaptation to complex carbohydrates and improve its potential functionality, we have analyzed its genome and transcriptome, as well as its metabolic output when growing in galacto-oligosaccharides derived from lactulose (GOS-Lu) as carbon source. B. pseudocatenulatum CECT 7765 shows strain-specific genome regions, including a great diversity of sugar metabolic-related genes. A preliminary and exploratory transcriptome analysis suggests candidate over-expression of several genes coding for sugar transporters and permeases; furthermore, five out of seven beta-galactosidases identified in the genome could be activated in response to GOS-Lu exposure. Here, we also propose that a specific gene cluster is involved in controlling the import and hydrolysis of certain di- and tri-saccharides, which seemed to be those primarily taken-up by the bifidobacterial strain. This was discerned from mass spectrometry-based quantification of different saccharide fractions of culture supernatants. Our results confirm that the expression of genes involved in sugar transport and metabolism and in the synthesis of leucine, an amino acid with a key role in glucose and energy homeostasis, was up-regulated by GOS-Lu. This was done using qPCR in addition to the exploratory information derived from the single-replicated RNAseq approach, together with the functional annotation of genes predicted to be encoded in the B. pseudocatenulatum CETC 7765 genome.

Comparative experimental investigation on the efficacy of mono- and multiprobiotic strains in non-alcoholic fatty liver disease prevention

BACKGROUND

To investigate the efficacy of different probiotic strains, their combinations and forms (alive or lyophilized) in nonalcoholic fatty liver disease (NAFLD) prevention.

METHODS

In this study, 70 rats have been used divided into 7 groups of 10 animals in each: I - intact rats, II-VII - rats with monosodium glutamate (MSG)-induced NAFLD. Rats with NAFLD were untreated (group II, MSG-obesity group) and treated with probiotics (groups III-VII). In order to develop NAFLD, newborn rats of groups II-VII were injected with a solution of monosodium glutamate (MSG) (4 mg/g) subcutaneously (s.c.) at 2nd,4th, 6th, 8th,10th postnatal day. The groups III-V received lyophilized monoprobiotics B. animalis VKL, B. animalis VKB, L.casei IMVB-7280, respectively. The group VI received 2.5 ml/kg of an aqueous solution of a mixture of the three probiotic strains (2:1:1 Lactobacillus casei IMVB-7280, Bifidobacterium animalis VKL, Bifidobacterium animalis VKB) at a dose of 50 mg/kg (5 × 10(9) CFU/kg) (g) (intragastrically). The group VII was treated with multiprobiotic "Symbiter" containing biomass of 14 alive probiotic strains (Lactobacillus + Lactococcus (6 × 10(10) CFU/g), Bifidobacterium (1 × 10(10)/g), Propionibacterium (3 × 10(10)/g), Acetobacter (1 × 10(6)/g)) at a dose of 140 mg/kg (1.4 × 10(10) CFU/kg). The treatment with probiotics was started at the age of 1 month. There were 3 courses of treatment, each included 2-week administration and 2-week break. All parameters were measured in 4-month aged rats.

RESULTS

Introduction of MSG during the neonatal period leads to the NAFLD development in the 4-months old rats. For steatosis degree there was no significant difference between MSG-obesity group and lyophilized monocomponent probiotics groups (III-V). The highest manifestation of steatosis was observed for B. animalis VKL group (2.0 ± 0.25) as compared to B. animalis VKB (1.70 ± 0.21) and L. casei IMVB-7280 (1.80 ± 0.20). The steatosis score changes between all monoprobiotics groups (III-V) were insignificant. Administration from birth of both alive (VII) and lyophilized (VI) probiotic mixture lead to a significant decrease by 69.5 % (p < 0.001) and 43.5 % (p < 0.025) of steatosis score respectively as compared to the MSG-obesity group (2.3 ± 0.21 %). For both alive and lyophilized probiotic mixtures, reduction of lobular inflammation was observed. These histological data were confirmed by the significant decrease of total lipids and triglycerides content in the liver approximately by 22-25 % in groups treated with probiotic mixtures (VI, VII) compared to the MSG-obesity group.

CONCLUSION

We established failure of NAFLD prevention with lyophilized monoprobiotic strains and the efficacy of probiotic mixture with the preference of alive probiotic strains.