Stachyose-enriched α-galacto-oligosaccharides regulate gut microbiota and relieve constipation in mice

Prebiotic stachyose inhibits PRDX5 activity and castration-resistant prostate cancer development

Stachyose (STA) is a prebiotic with poor oral bioavailability. In this study, we developed stachyose caproate (C6-STA), as a novel STA derivative, to demonstrate its high adsorption rate via oral administration. Pharmacokinetic analysis reveals that after absorption, the STA derived from C6-STA reaches its highest peak in the blood, liver, and kidney at 20 min, 30 min, and 12-24 h, with approximate levels of 1200 μg/mL, 0.14 μg/mL, and 0.2-0.3 μg/mL, respectively. In addition, the accumulation of STA in prostate tissues of mice with castration-resistant prostate cancer (CRPC) (1.75 μg/mg) is 10-fold higher than that in normal prostate tissues (0.14 μg/mg). The analysis also reveals that C6-STA has t1/2 of 12.8 h and Tmax of 0.25 h, indicating that it has the potential to be used as a promising drug in clinical practice. The toxicological evaluation shows no obvious side effects of C6-STA in mice administered with a 0.2 g/kg intragastric dose. Pharmacodynamic analysis and mechanism investigation of C6-STA show its ability to inhibit peroxiredoxin 5 (PRDX5) enzyme activity, disrupt PRDX5-nuclear factor erythroid 2-related factor 2 (NRF2) interaction, and decrease NAD(P)H quinone dehydrogenase 1 (NQO1) levels. NQO1 decrease further causes the accumulation of quinone radicals, which ultimately leads to the apoptosis of LNCaP cell-derived drug-tolerant persister (DTP) cells and slows CRPC progression. Our study discovered the anti-tumor activity of stachyose and shows that prebiotics have biological functions in vivo besides in the gut. Further investigation of C6-STA, especially in CRPC patients, is warranted.

Network meta-analysis of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults

OBJECTIVE

To compare the outcomes associated with the use of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults.

METHODS

We searched eight electronic databases from database inception to July 11, 2023, to identify randomized controlled trials (RCTs) that report efficacy and safety for the treatment of chronic constipation. The risk of bias in the included RCTs was evaluated according to the Cochrane tool, and the certainty of the evidence was assessed using the Confidence in Network Meta-Analysis framework. The analysis was conducted using R version 4.3.0.

RESULTS

Out of the 37 RCTs, a total of 21 different types of interventions were reported, involving 3,903 patients. This NMA demonstrated that both prebiotics and synbiotics resulted in an increase in frequency of stool movements per week. Compared to placebo, lactulose (Mean difference [MD] = 3.39, 95% Confdence interval [CI] [1.13, 5.65], moderate certainty), mix2 (consisting of Lactulose and Bacillus coagulans) (MD = 3.63, 95% CI [1.37, 5.89], moderate certainty), mix6 (consisting of Lactulose and Bifidobacterium coagulans) (MD = 4.30, 95% CI [1.04, 7.54], low certainty), and mix7 (consisting of Lactulose, Bifidobacterium subtilis, and Enterococcus faecium) (MD = 4.58, 95% CI [1.35, 7.78], moderate certainty) exhibited a significant effect. Notably, mix7 demonstrated the highest probability of being the most effective intervention (94.8%). Furthermore, when compared to L. plantarum, four probiotics and two synbiotics showed significant advantages in the Patient Assessment of Constipation Symptoms (PAC-SYM) score. L. reuteri (MD = -13.74, 95% CI [-22.20, -4.66], very low certainty) exhibited a significant effect in improving the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. In terms of safety, there were no statistically significant differences between the intervention and control groups in all adverse event analyses.

CONCLUSIONS

Moderate to very low evidence supports the use of lactulose and synbiotics to increase the number of weekly stool movements in patients, particularly highlighting the significant impact of synbiotics in increasing the number of weekly stool movements in patients with constipation. The use of L. paracasei showed improvements in PAC-SYM scores, while L. reuteri demonstrated enhancements in PAC-QoL scores.

Characteristics of stachyose-induced effects on gut microbiota and microbial metabolites in vitro associated with obesity in children

Childhood obesity presents a serious health concern associated with gut microbiota alterations. Dietary interventions targeting the gut microbiota have emerged as promising strategies for managing obesity in children. This study aimed to elucidate the impact of stachyose (STS) supplementation on the gut microbiota composition and metabolic processes in obese children. Fecal samples were collected from 40 obese children (20 boys and 20 girls) aged between 6 and 15 and in vitro fermentation was conducted with or without the addition of STS, respectively, followed by 16S rRNA amplicon sequencing and analysis of short-chain fatty acids (SCFAs) and gases. Notably, our results revealed that STS supplementation led to significant alterations in gut microbiota composition, including an increase in the abundance of beneficial bacteria such as Bifidobacterium and Faecalibacterium, and a decrease in harmful bacteria including Escherichia-Shigella, Parabacteroides, Eggerthella, and Flavonifractor. Moreover, STS supplementation resulted in changes in SCFAs production, with significant increases in acetate levels and reductions in propionate and propionate, while simultaneously reducing the generation of gases such as H2S, H2, and NH3. The Area Under the Curve (AUC)-Random Forest algorithm and PICRUSt 2 were employed to identify valuable biomarkers and predict associations between the gut microbiota, metabolites, and metabolic pathways. The results not only contribute to the elucidation of STS's modulatory effects on gut microbiota but also underscore its potential in shaping metabolic activities within the gastrointestinal environment. Furthermore, our study underscores the significance of personalized nutrition interventions, particularly utilizing STS supplementation, in the management of childhood obesity through targeted modulation of gut microbial ecology and metabolic function.

Exploring the effects of the dietary fiber compound mediated by a longevity dietary pattern on antioxidation, characteristic bacterial genera, and metabolites based on fecal metabolomics

BACKGROUND

Age-related dysbiosis of the microbiota has been linked to various negative health outcomes. This study aims to investigate the effects of a newly discovered dietary fiber compound (DFC) on aging, intestinal microbiota, and related metabolic processes. The DFC was identified through in vitro fermentation screening experiments, and its dosage and composition were determined based on a longevity dietary pattern.

METHODS

Aged SPF C57BL/6 J mice (65 weeks old) and young mice (8 weeks old) were divided into three groups: a subgroup without dietary fiber (NDF), a low DFC dose subgroup (LDF, 10% DFC), and a high DFC dose subgroup (HDF, 20% DFC). The total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD) activity, malondialdehyde (MDA) content, and glutathione peroxidase (GSH-Px) activity in liver and serum samples of the mice were measured according to the manufacturer's protocol. The expression levels of characteristic bacterial genera and fecal metabolite concentrations in mice were determined using quantitative real-time PCR (qPCR) and nuclear magnetic resonance hydrogen spectroscopy (1H NMR). Metabolomics analysis was further conducted to identify biological functions and potential pathways related to aging.

RESULTS

After an 8-weeks dietary intervention, DFC supplementation significantly attenuated age-related weight loss, organ degeneration, and oxidative stress. And promoted the growth of Lactobacillus and Bifidobacterium and inhibited the growth of Escherichia coli (E. coli) and Bacteroides (p < 0.05) in the intestinal tracts of aged mice. Metabolomic analysis identified glycolipid and amino acid metabolic pathway biomarkers associated with aging that were differentially regulated by DFC consumption. Correlation analysis between the identified microbial flora and the biomarkers revealed potential mechanistic links between altered microbial composition and metabolic activity with aging markers.

CONCLUSIONS

In conclusion, this study revealed an important mechanism by which DFC consumption impacts healthspan and longevity, shedding light on optimizing dietary fiber or developing fiber-based interventions to improve human health.

Exploring Impact of Probiotic-Fermented Soymilk on Dextran-Sulfate-Sodium-Induced Ulcerative Colitis via Modulating Inflammation and Gut Microbiota Profile

SCOPE

Lactic acid bacteria with probiotic functions and their fermentation products play a role in regulating ulcerative colitis (UC). This study investigates the potential role of fermented soymilk (FSM4) rich in isoflavones on DSS-induced UC.

METHODS AND RESULTS

Mice received 3% DSS and are supplemented daily once for 1 week by NFSM and FSM4. DSS usually causes intestinal inflammation and alters the gut microbiota. FSM4 intervention improves the UC-related inflammation and gut microbiota alteration. It considerably decreases pro-inflammatories such as TNF-α, IL-1β, and IL-6 in serum and COX-2 and MPO in colon tissues and pathogenic bacteria (Escherichia-Shigella). This facilitates gut-healthy bacteria growth. These healthy bacteria negatively correlat with pro-inflammatory factors but positively associated with acetic acid, butyric acid, and propionic acid, which may act for PPAR-γ pathway activating and NF-κB p65 pathway inhibiting, lowering the risk of UC. Overall, FSM4 might alleviate UC and significantly reverse the dysbiosis of gut microbiota via the PPAR-γ activation. It could be a good alternative for developing functional food to protect against UC.

CONCLUSION

FSM4 attenuates intestinal inflammation and modulates the SCFA-producing bacteria growth, which enable the PPAR-γ activation to alleviate the UC target, which could be a dietary intervention strategy for gut health.

Revisiting the Intestinal Microbiome and Its Role in Diarrhea and Constipation

The gut microbiota represents a community of microorganisms (bacteria, fungi, archaea, viruses, and protozoa) that colonize the gut and are responsible for gut mucosal structural integrity and immune and metabolic homeostasis. The relationship between the gut microbiome and human health has been intensively researched in the past years. It is now widely recognized that gut microbial composition is highly responsible for the general health of the host. Among the diseases that have been linked to an altered gut microbial population are diarrheal illnesses and functional constipation. The capacity of probiotics to modulate the gut microbiome population, strengthen the intestinal barrier, and modulate the immune system together with their antioxidant properties have encouraged the research of probiotic therapy in many gastrointestinal afflictions. Dietary and lifestyle changes and the use of probiotics seem to play an important role in easing constipation and effectively alleviating diarrhea by suppressing the germs involved. This review aims to describe how probiotic bacteria and the use of specific strains could interfere and bring benefits as an associated treatment for diarrhea and constipation.

Nondigestible Functional Oligosaccharides: Enzymatic Production and Food Applications for Intestinal Health

Nondigestible functional oligosaccharides are of particular interest in recent years because of their unique prebiotic activities, technological characteristics, and physiological effects. Among different types of strategies for the production of nondigestible functional oligosaccharides, enzymatic methods are preferred owing to the predictability and controllability of the structure and composition of the reaction products. Nondigestible functional oligosaccharides have been proved to show excellent prebiotic effects as well as other benefits to intestinal health. They have exhibited great application potential as functional food ingredients for various food products with improved quality and physicochemical characteristics. This article reviews the research progress on the enzymatic production of several typical nondigestible functional oligosaccharides in the food industry, including galacto-oligosaccharides, xylo-oligosaccharides, manno-oligosaccharides, chito-oligosaccharides, and human milk oligosaccharides. Moreover, their physicochemical properties and prebiotic activities are discussed as well as their contributions to intestinal health and applications in foods.

Probiotic Potential and Safety Assessment of Type Strains of Weissella and Periweissella Species

Although numerous strains belonging to the Weissella genus have been described in the last decades for their probiotic and biotechnological potential, others are known to be opportunistic pathogens of humans and animals. Here, we investigated the probiotic potential of two Weissella and four Periweissella type strains belonging to the species Weissella diestrammenae, Weissella uvarum, Periweissella beninensis, Periweissella fabalis, Periweissella fabaria, and Periweissella ghanensis by genomic and phenotypic analyses, and performed a safety assessment of these strains. Based on the results of the survival to simulated gastrointestinal transit, autoaggregation and hydrophobicity characteristics, as well as adhesion to Caco-2 cells, we showed that the P. beninensis, P. fabalis, P. fabaria, P. ghanensis, and W. uvarum type strains exhibited a high probiotic potential. The safety assessment, based on the genomic analysis, performed by searching for virulence and antibiotic resistance genes, as well as on the phenotypic evaluation, by testing hemolytic activity and antibiotic susceptibility, allowed us to identify the P. beninensis type strain as a safe potential probiotic microorganism. IMPORTANCE A comprehensive analysis of safety and functional features of six Weissella and Periweissella type strains was performed. Our data demonstrated the probiotic potential of these species, indicating the P. beninensis type strain as the best candidate based on its potential probiotic features and the safety assessment. The presence of different antimicrobial resistance profiles in the analyzed strains highlighted the need to establish cutoff values to perform a standardized safety evaluation of these species, which, in our opinion, should be mandatory on a strain-specific basis.

Eurotium cristatum reduces obesity by alleviating gut microbiota dysbiosis and modulating lipid and energy metabolism

BACKGROUND

Fuzhuan brick tea (FBT) has been shown to prevent obesity, but little is known about the effect of Eurotium cristatum, a critical fungus from FBT. This study examined the effects of live E. cristatum on lipid metabolism and gut microbiota composition in high-fat (HF) diet-induced obese mice.

RESULTS

Male HF diet-fed mice were treated with E. cristatum for 12 weeks. The results showed that E. cristatum administration caused strong inhibition against HF-induced body weight gain, dyslipidemia and liver oxidative stress damage. Additionally, Firmicutes and Bacteroidetes in phylum level and six types of bacterial including short-chain fatty acids (SCFAs) producing bacteria in genus level were found to be significantly changed in E. cristatum treated mice as compared to HF fed mice. As expected, E. cristatum could increase total SCFAs levels in feces. Interestingly, E. cristatum markedly increased the proportion of Akkermansia to resist obesity. Functional prediction analysis indicated that E. cristatum changed lipid and energy metabolism. Furthermore, E. cristatum ingestion can modulate hepatic acetyl-coa carboxylase (ACC), fatty acid synthase (FAS), sterol-regulatory element binding protein-1 (SREBP-1) and adipose uncoupling protein-1 (UCP-1) expression.

CONCLUSION

Conclusively, these findings suggest that E. cristatum can prevent the HF-induced lipid accumulation and other complications by modulating gut microbiota, lipid and energy metabolism. © 2022 Society of Chemical Industry.

Protective Effect of Dietary Polysaccharides from Yellow Passion Fruit Peel on DSS-Induced Colitis in Mice

Inflammatory bowel disease (IBD) is a complex inflammatory disorder characterized by chronic and spontaneously relapsing inflammation of the gastrointestinal tract. IBD includes two idiopathic disorders: Crohn’s disease (CD) and ulcerative colitis (UC). In particular, UC causes inflammation and ulceration of the colon and rectum. There is no cure for UC. The pharmacological treatment is aimed at controlling and/or reducing the inflammatory process and promoting disease remission. The present study investigated the possible protective effects of soluble dietary fiber (SDF) isolated from yellow passion fruit peel in the dextran sulfate sodium- (DSS-) induced colitis model in mice, induced by 5% of DSS. The animals were treated with SDF (10, 30, or 100 mg/kg (po)), and the disease activity index was monitored. Colon tissues were collected, measured, and prepared for oxidative stress, inflammation, and histology analysis. SDF improved body weight loss, colon length, and disease activity index and prevented colonic oxidative stress by regulating GSH levels and SOD activity. Furthermore, SDF reduced colonic MPO activity, TNF-α, and IL-1β levels and increased IL-10 and IL-6 levels. As observed by histological analysis, SDF treatment preserved the colonic tissue, the mucus barrier, and reduced inflammatory cell infiltration. Although this is a preliminary study, taken together, our data indicate that SDF may improve the course of DSS-UC. More studies are needed to explore and understand how SDF promotes this protection.

Alteration of intestinal microflora by the intake of millet porridge improves gastrointestinal motility

Foxtail millet (Setaria italica) has a long history of treating gastrointestinal ailments in China; however, little is known about the functional mechanism driving its therapeutic effects. The primary edible form of millet is porridge. This study investigates the effects of millet porridge on diphenoxylate-induced constipation and intestinal microflora in mice. Fifty mice were randomly divided into five groups: normal control group, constipation model group, and low-dose, medium-dose, and high-dose millet porridge groups. After 14 days of millet porridge gavage, constipation was induced and measured. The results showed that millet porridge prevented constipation by increasing the water content of feces, shortened the time of the first melena defecation, promoted gastric emptying, and improved the rate of gastrointestinal propulsion. Millet porridge also dose-dependently increased levels of Bifidobacterium and Lactobacillus and decreased levels of Escherichia coli, Enterococcus, and Bacteroides in the intestine. These results show that millet porridge could accelerate intestinal motility and change the proportions of intestinal flora and that it has a potent prebiotic effect.

High-fat diet and alcohol induced-mice could cause colonic injury through molecular mechanisms of endogenous toxins

Due to the complexity and diverse causes, the pathological mechanism of diet-induced colonic injury and colitis remains unclear. In this study, we studied the effects of the combination of a high-fat diet (HFD) plus alcohol on colonic injury in mice. We found HFD plus alcohol treatment induced disturbance of the gut microbiota; increased the production of intestinal toxins lipopolysaccharide (LPS), indole, and skatole; destroyed the stability of the intestinal mucosa; and caused the colonic epithelial cells damage through the activation of nuclear factor (NF)-κB and aromatic hydrocarbon receptors (AhR) signaling pathways. To mimic the effect of HFD plus alcohol in vivo, NCM460 cells were stimulated with alcohol and oleic acid with/without intestinal toxins (LPS, indole, and skatole) in vitro. Combinative treatment of alcohol and oleic acid caused moderate damage on NCM460 cells, while combination with intestinal toxins induced serious cell apoptosis. Western blot data indicated that the activation of NF-κB and AhR pathways further augmented after intestinal toxins treatment in alcohol- and oleic acid-treated colonic cells. This study provided new evidence for the relationship between diet pattern and colonic inflammation, which might partly reveal the pathological development of diet-induced colon disease and the involvement of intestinal toxins.

The role of functional oligosaccharides as prebiotics in ulcerative colitis

The incidence rate of ulcerative colitis (UC) has increased significantly over the past decades and it places an increasing burden on health and social systems. The current studies on UC implicate a strong correlation between host gut microbiota immunity and the pathogenesis of UC. Meanwhile, more and more functional oligosaccharides have been reported as prebiotics to alleviate UC, since many of them can be metabolized by gut microbiota to produce short-chain fatty acids (SCFAs). The present review is focused on the structure, sources and specific applications of various functional oligosaccharides related to the prevention and treatment of UC. The available evidence for the usage of functional oligosaccharides in UC treatment are summarized, including fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), chito-oligosaccharides (COS), alginate-oligosaccharides (AOS), xylooligosaccharides (XOS), stachyose and inulin.

Stachyose Alleviates Corticosterone-Induced Long-Term Potentiation Impairment via the Gut–Brain Axis

Stress can induce learning and memory impairment; corticosterone is often used to study the effects and mechanisms of stress in animal models. Long-term potentiation (LTP) has been widely used for tackling the mechanisms of memory. Liuwei Dihuang decoction-active fraction combination (LW-AFC) can improve stress-induced LTP and cognition impairment; stachyose is an oligosaccharide in LW-AFC. The effects and mechanisms of stachyose on stress are unknown. In this study, stachyose showed protective effects against LTP impairment by corticosterone in vivo only via intragastric administration for 7 consecutive days, but there was little effect even after direct intracerebroventricular injection; the protective effect of stachyose could be canceled by non-absorbable antibiotics (ATB) which disturbed gut flora. 16S rRNA sequencing, alpha diversity, and principal coordinate analysis (PCoA) revealed that the gut flora in corticosterone-treated mice was disturbed and stachyose could improve corticosterone-induced gut flora disturbance. Bacteroidetes were decreased and Deferribacteres were increased significantly in corticosterone-treated mice, and stachyose restored Bacteroidetes and Deferribacteres to the normal level. D-serine, a coactivator of NMDA receptors, plays an important role in synaptic plasticity and cognition. Here, corticosterone had little effect on the content of D-serine and L-serine (the precursor of D-serine), but it reduced the D-serine release-related proteins, Na⁺-independent alanine–serine–cysteine transporter-1 (ASC-1), and vesicle-associated membrane protein 2 (VAMP2) significantly in hippocampus; stachyose significantly increased ASC-1 and VAMP2 in corticosterone-treated mice, and ATB blocked stachyose’s effects on ASC-1 and VAMP2. NMDA receptors co-agonists L-serine, D-serine, and glycine significantly improved LTP impairment by corticosterone. These results indicated that stachyose might indirectly increase D-serine release through the gut–brain axis to improve LTP impairment by corticosterone in the hippocampus in vivo.

In Vivo Healthy Benefits of Galacto-Oligosaccharides from Lupinus albus (LA-GOS) in Butyrate Production through Intestinal Microbiota

Animal digestive systems host microorganism ecosystems, including integrated bacteria, viruses, fungi, and others, that produce a variety of compounds from different substrates with healthy properties. Among these substrates, α-galacto-oligosaccharides (GOS) are considered prebiotics that promote the grow of gut microbiota with a metabolic output of Short Chain Fatty Acids (SCFAs). In this regard, we evaluated Lupinus albus GOS (LA-GOS) as a natural prebiotic using different animal models. Therefore, the aim of this work was to evaluate the effect of LA-GOS on the gut microbiota, SCFA production, and intestinal health in healthy and induced dysbiosis conditions (an ulcerative colitis (UC) model). Twenty C57BL/6 mice were randomly allocated in four groups (n = 5/group): untreated and treated non-induced animals, and two groups induced with 2% dextran sulfate sodium to UC with and without LA-GOS administration (2.5 g/kg bw). We found that the UC treated group showed a higher goblet cell number, lower disease activity index, and reduced histopathological damage in comparison to the UC untreated group. In addition, the abundance of positive bacteria to butyryl-CoA transferase in gut microbiota was significantly increased by LA-GOS treatment, in healthy conditions. We measured the SCFA production with significant differences in the butyrate concentration between treated and untreated healthy groups. Finally, the pH level in cecum feces was reduced after LA-GOS treatment. Overall, we point out the in vivo health benefits of LA-GOS administration on the preservation of the intestinal ecosystem and the promotion of SCFA production.

Dietary synbiotic ameliorates constipation through the modulation of gut microbiota and its metabolic function

The purpose of this study is to investigate the mitigatory effect of a novel synbiotic (SBT) on constipation from the perspective of gut microbiome and metabolome. Here, intake of SBT effectively attenuated diphenoxylate-induced constipation, recuperated colonic epithelial integrity and increased serum levels of gastrointestinal excitatory neurotransmitters (P substance, vasoactive intestinal peptide, motilin, gastrin and serotonin). 16S rRNA sequencing showed that SBT intake rehabilitated the composition and functionality of gut microbiota. Relative abundances of short-chain fatty acids (SCFAs)-producing bacteria including Lactobacillus, Faecalibaculum and Bifidobacterium were elevated by administration of SBT. The gas chromatography-mass spectrometry analysis confirmed that fecal concentrations of propionate and butyrate were significantly increased in the rats intervened with SBT. In addition, SBT ingestion reduced the relative levels of opportunistic pathogens, such as Oscillibacter, Parasutterella and Parabacteroides. Microbial functional prediction showed that the relative abundances of lipopolysaccharide (LPS) biosynthesis and arachidonic acid metabolism were downregulated with SBT administration, which were in accordance with the serum metabolomics results. Furthermore, serum levels of LPS, tumour necrosis factor alpha and interleukin 6 were significantly decreased, indicating that SBT supplementation suppressed inflammatory responses. Therefore, this study demonstrated that consumption of SBT ameliorated constipation possibly by regulating gut microbiota, promoting the SCFAs production and inhibiting inflammatory responses in rats. Our study also indicated that SBT may provide a novel alternative strategy for the treatment of constipation clinically in future.

Stachyose inhibits vancomycin-resistant Enterococcus colonization and affects gut microbiota in mice

Vancomycin-resistant Enterococcus (VRE) caused nosocomial infections are rising globally. Multiple measures have been investigated to address this issue, altering gut microbiota through dietary intervention represents one of such effort. Stachyose can promote probiotic growth, which makes it a good candidate for potentially inhibiting VRE infection. This study aimed to determine whether stachyose inhibits VRE colonization and investigated the involvement of gut microbiota this effect of stachyose. In VRE-infection experiment, 6-week old female C57/6 J mice pre-treated with vancomycin were infected with 2 × 10⁸ CFU VRE via gavage. These mice then received oral administration of stachyose or PBS as control for 7days. Two groups of uninfected mice were also received daily gavage of stachyose or PBS for 7 days to observe the impact of stachyose treatment on normal mice. Fresh fecal and colon samples were collected, then VRE colonization, gut microbiota and gene expression were respectively assessed using cultivation, 16s rRNA sequencing and RNA-sequencing in two parallel experiment, respectively. In VRE-infected mice, stachyose treatment significantly reduced VRE colonization on days 9 and 10 post-infection. Stachyose treatment increased the relative abundance of Porphyromonadaceae, Parabacteroides, and Parabacteroides distasonis compared to the PBS-treated infection mice (P < 0.01). Uninfected mice treated with stachyose showed a significant increase in Lactobacillaceae and Lactobacillus compared to the PBS-treated uninfected mice(P < 0.05). RNA-sequencing results showed that stachyose treatment in VRE-infected mice increased expression of genes involved in TNF and IL-17 signaling pathways. Stachyose treatment also up-regulated Hsd17b14, Cyp3a44, Arg1, and down-regulated Pnliprp2, Ces1c, Pla2g4c genes involving in metabolic pathway in uninfected mice. In conclusion, stachyose supplementation can effectively inhibit VRE colonization and probably altering composition of the microbiome, which can in turn result in changes in expression of genes. Stachyose may also benefit health by increasing the abundance of Lactobacillus and expression of genes involving in metabolic pathway in normal mice.

Effects of inulin and isomalto-oligosaccharide on diphenoxylate-induced constipation, gastrointestinal motility-related hormones, short-chain fatty acids, and the intestinal flora in rats

The prebiotics inulin (INU) and isomalto-oligosaccharide (IMO) influence intestinal health and immunity, but their effects on constipation are not clearly established. We evaluated the effects of INU and IMO in a rat model of diphenoxylate-induced constipation. Twenty-four male rats were divided into four groups: basal diet (Con), 40 mg kg-1 diphenoxylate (PCon), 20 g kg-1 INU and treated with 40 mg kg-1 diphenoxylate, and 20 g kg-1 IMO and treated with 40 mg kg-1 diphenoxylate. INU and IMO increased the number, weight, and water content of fecal pellets, and decreased the time to the first black stool in rats with constipation. Serum levels of the gastrointestinal motility-related hormones adrenocorticotropic hormone (ACTH), motilin (MTL), and Substance P (SP) were higher and corticosterone (CORT), vasoactive intestinal peptide (VIP), and calcitonin gene-related peptide (CGRP) were lower in rats treated with prebiotics than in untreated rats. Colon tissue levels of MTL and SP were increased, and VIP and CGRP were decreased by prebiotics. Furthermore, in rats with constipation, INU and IMO increased the colonic contents of short-chain fatty acids. The relative abundance of Bacteroidetes was lower in the prebiotics groups than in the Con and PCon groups. Lactobacillus was more abundant in the INU and IMO groups than in PCon rats. Lactobacillus reuteri and Lactobacillus intestinalis were more abundant in the IMO group than in the PCon group (P < 0.01), and L. intestinalis was more abundant in the INU group than in the PCon group (P < 0.01). In summary, INU and IMO improved constipation and altered the intestinal microbiota in a rat model of constipation.

Do Bioactive Food Compound with Avena sativa L., Linum usitatissimum L. and Glycine max L. Supplementation with Moringa oleifera Lam. Have a Role against Nutritional Disorders? An Overview of the In Vitro and In Vivo Evidence

Functional clinical nutrition is an integrative science; it uses dietary strategies, functional foods and medicinal plants, as well as combinations thereof. Both functional foods and medicinal plants, whether associated or not, form nutraceuticals, which can bring benefits to health, in addition to being included in the prevention and treatment of diseases. Some functional food effects from Avena sativa L. (oats), Linum usitatissimum L. (brown flaxseed), Glycine max L. (soya) and Moringa oleifera have been proposed for nutritional disorders through in vitro and in vivo tests. A formulation called a bioactive food compound (BFC) showed efficiency in the association of oats, flaxseed and soy for dyslipidemia and obesity. In this review, we discuss the effects of BFC in other nutritional disorders, as well as the beneficial effects of M. oleifera in obesity, cardiovascular disease, diabetes mellitus type 2, metabolic syndrome, intestinal inflammatory diseases/colorectal carcinogenesis and malnutrition. In addition, we hypothesized that a BFC enriched with M. oleifera could present a synergistic effect and play a potential benefit in nutritional disorders. The traditional consumption of M. oleifera preparations can allow associations with other formulations, such as BFC. These nutraceutical formulations can be easily accepted and can be used in sweet preparations (fruit and/or vegetable juices, fruit and/or vegetable vitamins, porridges, yogurt, cream, mousses or fruit salads, cakes and cookies) or savory (vegetable purees, soups, broths and various sauces), cooked or not. These formulations can be low-cost and easy-to-use. The association of bioactive food substances in dietary formulations can facilitate adherence to consumption and, thus, contribute to the planning of future nutritional interventions for the prevention and adjuvant treatment of the clinical conditions presented in this study. This can be extended to the general population. However, an investigation through clinical studies is needed to prove applicability in humans.

Microbiome-metabolomic analyses of the impacts of dietary stachyose on fecal microbiota and metabolites in infants intestinal microbiota-associated mice

BACKGROUND

The intestinal microbiota and metabolites play an important role in human health and immunity. However, few studies have investigated the long-term effects of stachyose on the human intestinal microbiota and metabolism. Therefore, in this study, the feces of infants were transplanted into germ-free mice, and the effect of long-term stachyose intake on intestinal metabolism was examined by comparing the results of microbiome and metabolome analyses. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to study the effects of stachyose intake on the metabolites and metabolic pathways of the transplanted human intestinal microbiota.

RESULTS

We observed that stachyose significantly altered the composition of the intestinal microbiota and metabolites, up-regulated production of the metabolite taurocholic acid, down-regulated amino acid metabolism, and significantly regulated the metabolism of taurine and hydroxytaurine, pantothenate and coenzyme A (CoA) biosynthesis, and other signaling pathways.

CONCLUSION

These findings may provide a basis for elucidating the mechanism by which stachyose promotes host health. © 2020 Society of Chemical Industry.

Metabolome analysis and chemical profiling of Indonesian royal jellies as the raw material for cosmetic and bio-supplement products

Royal jellies (RJs) possess moisturizing, emulsifying, and stabilizing properties, and several pharmacological activities have also been found to be present, which make them an ideal component for cosmetic and skin care products. However, despite the abundant efficacies, there is a lack of studies that explore the chemical composition of RJ using metabolome analysis. Furthermore, an evaluation of the chemical composition of Indonesian RJs collected from different regions has yet to be carried out. Therefore, the main objective of this study was to identify any differences in the chemical composition of such RJs. Chemical profiling was also carried out to enable more targeted utilization based on the actual compositions. Chemical profiling is also important given the rich Indonesian biodiversity and the high dependence of the RJ compositions on the botanical source. In this research, ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used as part of an untargeted metabolomics approach. From the chemical profiling, >30 compounds were identified across four RJ samples. The major constituents of the samples were found to be oligosaccharides, fatty acids, and adenosine monophosphate derivatives. Meanwhile, sucrose and planteose were found to be highest in the samples from Banjarnegara and Kediri, whereas dimethyloctanoic acid was found to be unique to the sample from Banjarnegara. It was also discovered that the RJs from Demak and Tuban contained more organic fatty acids and oligosaccharides than the other samples. Although the sample from Demak demonstrated good potential for use in the cosmetic, skin care, and bio-supplement industries, the higher abundance of fatty acids and oligosaccharides in the sample from Tuban indicated that it is perhaps the most suitable RJ for use in this field.

A strain of Bacteroides thetaiotaomicron attenuates colonization of Clostridioides difficile and affects intestinal microbiota and bile acids profile in a mouse model

Clostridioides difficile infection (CDI) is a growing global public health threat. While fecal microbiota transplantation (FMT) is an effective therapy for CDI, a number of challenges limit its application. Studies suggest that probiotics may be a promising alternative therapy. In the current study, we evaluated whether Bacteroides thetaiotaomicron (B. thetaiotaomicron) would inhibit colonization of toxigenic BI/NAP1/027 C. difficile in a mouse model. We found that B. thetaiotaomicron administration decreased the copies of C. difficile and inhibited inflammation in the colon. 16S rRNA sequencing showed that B. thetaiotaomicron administration was associated with a significantly increased relative abundance of Bacteroidetes and decreased level of Proteobacteria, leading to the reversal of the effect of antibiotics treatment and C. difficile infection on microbiota. B. thetaiotaomicron administration was associated with increases in the concentrations of alpha-muricholic acid, beta-muricholic acid, 12 ketolithocholic acid, and deoxycholic acid which are known to inhibit the growth of C. difficile, as well as reductions in the level of taurocholic acid, which promotes germination of C. difficile. Altered profile of major high abundance bile acids by B. thetaiotaomicron administration was similar to that with FMT treatment. Based on these results, we proposed the concept of "the ratio of promotion/inhibition BAs" which would advance our understanding of the relation of C. difficile and BAs.

Development and assessment of GC/MS and HPAEC/PAD methodologies for the quantification of α-galacto-oligosaccharides (GOS) in dry beans (Phaseolus vulgaris)

The quantification of α-Galacto-oligosaccharides (GOS) in beans has been increasingly approached through different methodologies. However, reported GOS contents revealed up to 8-times disparity, which cannot be only attributed to the bean cultivar and underlines the need of using validated analytical methodologies. This study aimed to optimize and validate the extraction of the most abundant GOS found in beans, namely raffinose, stachyose and verbascose, and comparatively assess their determination by High-Performance Anion Exchange Chromatography/Pulsed Amperometric Detector (HPAEC/PAD) and Gas Chromatography/Mass Spectrometry (GC/MS). Hot sonication followed by shaking with 70% ethanol resulted in excellent GOS extraction efficiencies (92.54-107.94%). GC/MS determination was more reliable than HPAEC/PAD, with limits of quantification of 4.48-224.31 mg/kg and intra/inter-day repeatabilities <10%. The analysis of six bean varieties proved the feasibility of the GC/MS methodology, displaying total GOS contents from 1453.07 ± 169.31 to 2814.34 ± 95.28 mg/100 g. Stachyose was significantly (p < 0.05) the main GOS in all samples.

1H NMR-Based Fecal Metabolomics Reveals Changes in Gastrointestinal Function of Aging Rats Induced by d-Galactose

d-galactose (d-gal) is widely used to induce aging. However, it is still unclear whether long-term injection of d-gal affects the gastrointestinal functions of aging rats, and how. In this study, we investigated the effects of d-gal on the gastrointestinal functions of aging rats, especially from the perspective of fecal metabolomics. Biochemical and behavioral analyses were performed. Besides, a ¹H NMR-based metabolomics approach was built and applied in combination with multivariate data analysis including principal components analysis (PCA) and orthogonal partial least squares-discriminate analysis (OPLS-DA). Regarding gastrointestinal functions, d-gal significantly decreased the small intestine propulsion rates and prolonged gastrointestinal transit time. In addition, d-gal significantly increased the oxidative damages. PCA results showed that d-gal interrupted the metabolic profiles of endogenous small molecules in aging rats. Furthermore, OPLS-DA showed that 40 metabolites were screened and identified to be involved in the disruption of gastrointestinal functions in aging rats. Accordingly, seven metabolic pathways were recognized as the most influenced pathways associated with gastrointestinal functions of aging rats induced by d-gal, including amino acid metabolism, energy metabolism, intestinal flora metabolism, and metabolism of short chain fatty acids. It is the first report to investigate the effects and underlying mechanisms of d-gal on gastrointestinal functions of aging rats from the perspective of fecal metabolomics. The current results are conducive to further comprehensively understand d-gal-induced aging and will expand the applications of d-gal in pharmacological researches.

Soy bioactive peptides and the gut microbiota modulation

The balance of protein, carbohydrate, and fat affect the composition and functions of the gut microbiota. The complexities involved thereof require insights into the roles and impacts of individual dietary components due to the difficulty of defining such in a group of others. Peptides and proteins from several animal and plant sources have been widely explored in relation to the gut microbiome modulation, but the effects of soy peptides and other soy derivatives on the gut microbiota are largely unexplored. This piece considered an overview of the production and interventions of soy bioactive peptides on gut, as they affect the composition and functions of the gut microorganisms. A mini review on the production of soy protein hydrolysates/peptides and highlights of the most recent knowledge regarding their physiological effects on host's gut microbiota cum health were investigated. Overall deductions and research gaps were critically evaluated for futuristic interventions and relevance. Key points • Diet affects the composition of gut microorganisms. • Modulation of the gut microbiota by soy biopeptides is described. • Critical deductions on personal and commercial use are provided.

How Food Affects Colonization Resistance Against Enteropathogenic Bacteria

Food has a major impact on all aspects of health. Recent data suggest that food composition can also affect susceptibility to infections by enteropathogenic bacteria. Here, we discuss how food may alter the microbiota as well as mucosal defenses and how this can affect infection. Salmonella Typhimurium diarrhea serves as a paradigm, and complementary evidence comes from other pathogens. We discuss the effects of food composition on colonization resistance, host defenses, and the infection process as well as the merits and limitations of mouse models and experimental foods, which are available to decipher the underlying mechanisms.

Beneficial effects of lactitol on the composition of gut microbiota in constipated patients

OBJECTIVE

To explore the changes in microbial composition and the corresponding impact after lactitol treatment in constipated patients.

METHODS

Altogether 29 consecutive outpatients diagnosed with chronic constipation from three centers were recruited and stratified based on their history of diabetes mellitus. All patients were administered with oral lactitol for 2 weeks, and a symptoms diary of constipation was recorded. Fecal samples were collected before and after lactitol treatment, and were analyzed by 16S rRNA sequencing and real-time polymerase chain reaction (PCR) to detect gut microbiota.

RESULTS

Twenty patients with diabetes mellitus and nine without, all with chronic constipation, were enrolled in this study. After 2-week administration of lactitol, their subscale scores and constipation symptoms significantly decreased (P < 0.05). An analysis of fecal flora using 16S rRNA sequencing found an increasing trend of abundance of Bifidobacterium in the post-lactitol group (P = 0.08). Actinobacteria, Actinobacteria, Bifidobacteriales, Bifidobacteriaceae and Bifidobacterium were significantly more abundant after lactitol administration. Real-time PCR showed significantly high DNA copy numbers of Bifidobacterium after lactitol treatment (1.39 × 10¹⁰ vs 2.74 × 10⁹ copies/μL, P = 0.01). The results of 16S rRNA sequencing and real-time PCR illustrated an increasing trend of Bifidobacterium in both patients with and without diabetes. In addition, Bifidobacterium was negatively correlated with constipation subscale scores.

CONCLUSIONS

Alterations in fecal flora composition after lactitol supplementation, especially in terms of an increasing trend of Bifidobacterium, alleviated constipation symptoms. Lactitol may be a promising prebiotic candidate for patients with constipation, regardless of diabetes mellitus.

Stachyose modulates gut microbiota and alleviates dextran sulfate sodium-induced acute colitis in mice

BACKGROUND/AIM

Ulcerative colitis (UC) has been implicated to imbalanced enteric flora and reduced microbial diversity. Stachyose is a kind of natural prebiotic which favorably modulate the composition of the gut microbiota. The present study aims to investigate the effects of stachyose on inflammatory levels and gut microbiota of acute colitis mice.

MATERIALS AND METHODS

In this study, the mice were randomly divided into four groups: (1) control group; (2) stachyose group; (3) dextran sulfate sodium (DSS) group; (4) stachyose + DSS group. Hemotoxylin and Eosin (H and E) staining was performed for the distal colon to examine the inflammation and tissue damage. The inflammatory cytokines including IL-6, IL-10, IL-17a, and TNF-α in serum were determined by ELISA assay. The differences in the gut microbiota were analyzed by 16S rDNA gene sequencing.

RESULTS

Histological assay showed that the stachyose treatment significantly reduced the lesions of the colon in DSS-induced colitis. And the upregulated inflammatory cytokines induced by DSS were significantly inhibited by stachyose treatment. Additionally, the sequencing analysis showed that the stachyose changed the gut microbiota composition with a higher level of Akkermansia, as well as selectively increasing some probiotics, including Lactobacillus.

CONCLUSIONS

Our results suggested that stachyose increased beneficial microbiota and bacterial diversity to alleviate acute colitis in mice, which might be a new promising option to UC patients.

Diet and the Human Gut Microbiome: An International Review

This review summarizes the key results of recently published studies on the effects of dietary change and nutritional intervention on the human microbiome from around the world, focusing on the USA, Canada, Europe, Asia, and Africa. It first explores mechanisms that might explain the ability of fiber-rich foods to suppress the incidence and mortality from westernized diseases, notably cancers of the colon, breast, liver, cardiovascular, infectious, and respiratory diseases, diabetes, and obesity (O'Keefe in Lancet Gastroenterol Hepatol 4(12):984-996, 2019; Am J Clin Nutr 110:265-266, 2019). It summarizes studies from Africa which suggest that disturbance of the colonic microbiome may exacerbate chronic malnutrition and growth failure in impoverished communities and highlights the importance of breast feeding. The American section discusses the role of the microbiome in the swelling population of patients with obesity and type 2 diabetes and examines the effects of race, ethnicity, geography, and climate on microbial diversity and metabolism. The studies from Europe and Asia extoll the benefits of whole foods and plant-based diets. The Asian studies examine the worrying changes from low-fat, high-carbohydrate diets to high-fat, low-carbohydrate ones and the increasing appearance of westernized diseases as in Africa and documents the ability of high-fiber traditional Chinese diets to reverse type 2 diabetes and control weight loss. In conclusion, most of the studies reviewed demonstrate clear changes in microbe abundances and in the production of fermentation products, such as short-chain fatty acids and phytochemicals following dietary change, but the significance of the microbiota changes to human health, with the possible exception of the stimulation of butyrogenic taxa by fiber-rich foods, is generally implied and not measured. Further studies are needed to determine how these changes in microbiota composition and metabolism can improve our health and be used to prevent and treat disease.

Interactions of tea polyphenols with intestinal microbiota and their implication for anti-obesity

Tea polyphenols (TP) are the main components in tea. Studies in vitro have shown they have significant biological activity; however, the results are inconsistent with experiments in vivo. For the low bioavailability, most TP are thought to remain in the gut and metabolized by intestinal bacteria. In the gut, the unabsorbed TP are metabolized to a variety of derivative products by intestinal flora, which may accumulate to exert beneficial effects. Numerous studies have shown that TP can inhibit obesity and its related metabolism disorders effectively. Meanwhile, it has demonstrated that TP and their derivatives may modulate intestinal micro-ecology. The understanding of the interaction between TP and intestinal microbiota will allow us to better evaluate the contribution of microbial metabolites of TP to anti-obesity activity. This review showed implications for the use of TP as functional food with potential therapeutic utility against obesity by modulating intestinal microbiota, contributing to the improvement of human health. © 2019 Society of Chemical Industry.

GH36 α-galactosidase from Lactobacillus plantarum WCFS1 synthesize Gal-α-1,6 linked prebiotic α-galactooligosaccharide by transglycosylation

α-Galactosidases are potent industrial glycoside hydrolases which are relatively less explored for their transglycosylation potential, especially from Lactobacillus genera. A GH36 α-galactosidase from Lactobacillus plantarum WCFS1 was cloned and over expressed in Hi-control Escherichia coli BL21(DE3). Ni-NTA affinity gel chromatography resulted in purified α-galactosidase (LpαG; specific activity 3077.35 U mg^-1) having a monomeric weight of ~80 kDa with 29.3% yield. Size exclusion chromatography of LpαG showed native molecular mass of ~240.5 kDa. LpαG displayed optimum activity at pH 6 and 37 °C. The K_m,V_max and k_cat/K_m of LpαG towards pNPαGal were found to be 0.93 mM and 714.3 μmol ml^-1 min^-1 and 12,075 s^-1 mM^-1, respectively. LpαG displayed maximum transglycosylation activity towards melibiose substrate (as both donor and acceptor) and synthesized majorly a trisaccharide with 0.26 mg ml^-1 yield. Nuclear magnetic resonance (NMR) characterization revealed that trisaccharide consist of only single species of α-linked galactooligosaccharide (manninotriose; α-d-Galp-(1 → 6)-α-d-Galp-(1 → 6)-d-Glcp) with α-(1 → 6) regioselectivity. Manninotriose displayed prebiotic property by supporting the growth of probiotic L. plantarum WCFS1 and Bifidobacteria adolescentis DSM 20083.

Prebiotic UG1601 mitigates constipation-related events in association with gut microbiota: A randomized placebo-controlled intervention study

BACKGROUND

Constipation is a common functional gastrointestinal disorder and its etiology is multifactorial. Growing evidence suggests that intestinal dysbiosis is associated with the development of constipation. Prebiotics are subjected to bacterial fermentation in the gut to produce short-chain fatty acids (SCFAs), which can help relieve constipation symptoms. The prebiotic UG1601 consists of inulin, lactitol, and aloe vera gel, which are known laxatives, but randomized, controlled clinical trials that examine the effects of this supplement on gut microbiota composition are lacking.

AIM

To assess the efficacy of the prebiotic UG1601 in suppressing constipation-related adverse events in subjects with mild constipation.

METHODS

Adults with a stool frequency of less than thrice a week were randomized to receive either prebiotics or a placebo supplement for 4 wk. All participants provided their fecal and blood samples at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were evaluated. The concentrations of serum endotoxemia markers and fecal SCFAs were determined. The relative abundance of SCFA-producing bacteria and the gut microbial community in the responders and non-responders in the prebiotics supplementation group were evaluated.

RESULTS

There were no significant differences in gastrointestinal symptoms between groups, although the prebiotic group showed greater symptom improvement. However, after prebiotic usage, serum cluster of differentiation (CD) 14 and lipopolysaccharide (LPS) concentrations were significantly decreased (CD14, P = 0.012; LPS, P < 0.001). The change in LPS concentration was significantly larger in the prebiotic group than in the placebo group (P < 0.001). Fecal SCFAs concentrations did not differ between groups, while the relative abundance of Roseburia hominis, a major butyrate producer, was significantly increased in the prebiotic group (P = 0.045). The abundances of the phylum Firmicutes and the family Lachnospiraceae (phylum Firmicutes, class Clostridia) (P = 0.009) were decreased in the responders within the prebiotic group. In addition, the proportions of the phylum Firmicutes, the class Clostridia, and the order Clostridiales were inversely correlated with several fecal SCFAs (P < 0.05).

CONCLUSION

Alterations in gut microbiota composition, including a decrease in the phylum Firmicutes and an increase in butyrate-producing bacteria, following prebiotic UG1601 supplementation might help alleviate symptom scores and endotoxemia.

Regulatory Effects of Stachyose on Colonic and Hepatic Inflammation, Gut Microbiota Dysbiosis, and Peripheral CD4+ T Cell Distribution Abnormality in High-Fat Diet-Fed Mice

A long-term high-fat diet (HFD) can cause a range of health problems. Gut microbiota plays a decisive role in the development of HFD-associated inflammation, involved in function of T cells. This study was designed to probe the regulative effects of dietary stachyose, a functional oligosaccharide, on HFD-induced weight gain, inflammation, gut microbiota dysbiosis, and T cell abnormality in C57Bl/6 mice. Mice were divided into three groups which received normal chow, HFD and HFD plus stachyose (400 mg/kg), respectively. Results showed that administration of stachyose diminished the HFD-induced upregulation of serum TNF-α level and elevation of peripheral blood leukocyte populations to alleviate the HFD-caused colonic and hepatic inflammation in mice. Analysis of gut microbiota revealed that stachyose improved the intestinal homeostasis of HFD-fed mice by improving the bacterial diversity with the increases in the relative abundances of the Prevotellaceae_NK3B31_group, Parasutterella, Christensenellaceae_R-7_group, and Anaerovorax, as well as the fecal level of butanoic acid, while decreasing the ratio of Firmicutes-to-Bacteroidetes and the abundances of the Lachnospiraceae_NK4A136_group, Desulfovibrio, Anaerotruncus, Mucispirillum, Roseburia, and Odoribacter. Flow cytometric analysis showed that stachyose antagonized the HFD-induced decrease of peripheral CD4⁺ T cell population in mice. Conclusively, these findings suggest that long-term consumption of stachyose can ameliorate the HFD-associated colonic and hepatic inflammation and its complications by modulating gut microbiota.

Protective effects of α-galacto-oligosaccharides against a high-fat/western-style diet-induced metabolic abnormalities in mice

In this study, we investigated the effects of a newly synthesized α-galacto-oligosaccharide mixture (α-GOSg), 0.5% in drinking water, on high-fat/western-style diet (HFWD)-induced metabolic abnormality in mice in a study of 13 weeks. Raffinose family oligosaccharides (RFOs) were included as a comparison. Mice treated with α-GOSg had significantly lower body weight and body fat (p < 0.05), while RFOs were less effective. Both α-GOSg and RFOs significantly reduced serum levels of total cholesterol and low-density lipoprotein cholesterol, alanine aminotransferase and liver lipids. However, only α-GOSg significantly decreased the histopathological score for liver steatosis and downregulated hepatic fatty acid synthesis gene acetyl CoA carboxylase-α. α-GOSg also significantly reduced the content of bile acids in the small intestine and significantly increased the abundance of gut Bifidobacterium and decreased the abundance of Clostridium leptum. These actions are proposed to be key mechanisms contributing to the beneficial health effects of α-GOSg.

Active fraction combination from Liuwei Dihuang decoction (LW-AFC) ameliorates corticosterone-induced long-term potentiation (LTP) impairment in mice in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Liuwei Dihuang decoction (LW), a classic formula in Traditional Chinese medicine (TCM), has been used for nearly one thousand years for various diseases with characteristic features of kidney yin deficiency. LW consists of 6 herbs including Dihuang (prepared root of Rehmannia glutinosa (Gaertn.) DC.), Shanyao (rhizome of Dioscorea polystachya Turcz.), Shanzhuyu (fruit of Cornus officinalis Siebold & Zucc.), Mudanpi (root bark of Paeonia × suffruticosa Andrews), Zexie (rhizome of Alisma plantago-aquatica L.) and Fuling (scleorotia of Wolfiporia extensa (Peck) Ginns). LW-active fraction combination (LW-AFC) is extracted from LW, it is effective for the treatment of kidney yin deficiency in many animal models. Recent researches indicate that the "kidney deficiency" is related to a disturbance in the neuroendocrine immunomodulation (NIM) network, and glucocorticoids play an important role in kidney deficiency.

AIM OF THE STUDY

This study evaluated the effects of LW-AFC and the active fractions (polysaccharide, LWB-B; glycoside, LWD-b; oligosaccharide, CA-30) on corticosterone (Cort)-induced long-term potentiation (LTP) impairment in vivo.

MATERIALS AND METHODS

In this study, LTP was used to evaluate the synaptic plasticity. LW-AFC was orally administered for seven days. The active fractions were given by either chronic administration (i.g., i.p., 7 days) or single administration (i.c.v., i.g., i.p.). Cort was injected subcutaneously 1 h before the high-frequency stimulation (HFS) to induce LTP impairment. Moreover, in order to research on the possible effective pathways, an antibiotic cocktail and an immunosuppressant were also used.

RESULTS

Chronic administration (i.g.) of LW-AFC and its three active fractions could ameliorate Cort-induced LTP impairment. Single administration (i.c.v., i.g., i.p.) of any of the active fractions had no effect on Cort-induced LTP impairment, while chronic administration (i.g., i.p.) of LWB-B or LWD-b showed positive effects against Cort. Interestingly, CA-30 only showed protective effects via i.g. administration, and there was little effect when CA-30 was administered i.p. In addition, when the intestinal microbiota was disrupted by application of the antibiotic cocktail, CA-30 showed little protective effects against Cort. The effects of LW-AFC were also abolished when the immune function was inhibited. In the hippocampal tissue, Cort treatment increased corticosterone and glutamate, and LW-AFC could inhibit the Cort-induced elevation of corticosterone and glutamate; there was little change in D-serine in Cort-treated animals, but LW-AFC could increase the D-serine levels.

CONCLUSION

LW-AFC and its three active fractions could ameliorate Cort-induced LTP impairment. Their protective effects are unlikely by a direct way, and immune modulation might be the common pathway. CA-30 could protect LTP from impairment via modulating the intestinal microbiota. Decreasing corticosterone and glutamate and increasing D-serine in the Cort-treated animals' hippocampal tissue might be one of the mechanisms for the neural protective effects of LW-AFC. Further study is needed to understand the underlying mechanisms.

Food Supplements to Mitigate Detrimental Effects of Pelvic Radiotherapy

Pelvic radiotherapy has been frequently reported to cause acute and late onset gastrointestinal (GI) toxicities associated with significant morbidity and mortality. Although the underlying mechanisms of pelvic radiation-induced GI toxicity are poorly understood, they are known to involve a complex interplay between all cell types comprising the intestinal wall. Furthermore, increasing evidence states that the human gut microbiome plays a role in the development of radiation-induced health damaging effects. Gut microbial dysbiosis leads to diarrhea and fatigue in half of the patients. As a result, reinforcement of the microbiome has become a hot topic in various medical disciplines. To counteract GI radiotoxicities, apart from traditional pharmacological compounds, adjuvant therapies are being developed including food supplements like vitamins, prebiotics, and probiotics. Despite the easy, cheap, safe, and feasible approach to protect patients against acute radiation-induced toxicity, clinical trials have yielded contradictory results. In this review, a detailed overview is given of the various clinical, intestinal manifestations after pelvic irradiation as well as the role of the gut microbiome herein. Furthermore, whilst discussing possible strategies to prevent these symptoms, food supplements are presented as auspicious, prophylactic, and therapeutic options to mitigate acute pelvic radiation-induced GI injury by exploring their molecular mechanisms of action.

Lactobacillus casei Strain Shirota Alleviates Constipation in Adults by Increasing the Pipecolinic Acid Level in the Gut

The benefits of probiotics for constipation are widely accepted, but the mechanisms involving gut metabolites are unclear. In this study, we investigated the effects of Lactobacillus casei strain Shirota (LcS) on constipated patients and revealed that a metabolite mediator is involved in the LcS-induced constipation alleviation. Sixteen constipated patients and 22 non-constipated participants were recruited. The subjects consumed 100 mL of an LcS beverage (10⁸ CFU/mL) per day for 28 days. The fecal non-volatile metabolites were determined by GC/MS, and the targeted metabolites were further verified in a constipated mouse model. In constipated patients, LcS intervention significantly improved defecation frequency (from 4.81 to 7.81 times per week, p < 0.05), stool consistency (from 2.52 to 3.68, p < 0.05) and constipation-related symptoms. A total of 14 non-volatile fecal metabolites were obtained as potential constipation-related metabolites that were regulated by LcS. Among these metabolites, pipecolinic acid (PIPA) had a significant positive correlation with defecation frequency in constipated patients. PIPA significantly promoted the small intestinal propulsive rate (from 25.45 to 39.68%) and increased the number of fecal pellets (from 30.38 to 57.38 pellets) in constipated mice (p < 0.05). The 5-hydroxytryptamine (5-HT) and acetylcholine (ACh) in colonic tissue may be partly involved in PIPA-mediated constipation alleviation. In conclusion, PIPA was a metabolic mediator in the gut that participated in LcS-induced constipation alleviation.

Study on the ability of partially hydrolyzed guar gum to modulate the gut microbiota and relieve constipation

The aim of this study was to evaluate the effects of high- (HHGG, Mw 10,000-30,000 Da) and medium-molecular-weight (MHGG, Mw 2,000-10,000 Da) partially hydrolyzed guar gum (PHGG) on modulation of gut microbiota and relief of constipation in mice. Mice were treated with galacto-oligosaccharide (GOS) and xylo-oligosaccharide (XOS) at a dose of 1 g/kg bw as positive controls. Low- and high-dose HHGG and MHGG groups received 250 mg or 1 g/kg bw, respectively. Treatment was administered intragastrically for 15 days, and constipation model was induced by loperamide lavage at d 16. PHGG could increase fecal moisture and small intestinal transit and shortened the time to first black stool defecation after constipation. The highest short-chain fatty acid production was observed in the high-dose MHGG group. Additionally, PHGG, GOS, and XOS predominantly promoted the accumulation of Bacteroidetes and inhibited the growth of Desulfovibrio. This study suggested that MHGG treatment could elicit constipation relief in mice. PRACTICAL APPLICATIONS: In this study, partially hydrolyzed guar gum (PHGG) produced by mannanase hydrolysis was applied for the relieving constipation in mice. The medium-molecular-weight product (Mw 2,000-10,000 Da) could elicit constipation relief and modulate the gut microbiota in mice, which shows the potential to act as dietary fiber for constipation treatment.

Immunomodulatory Effects of Enzymatic-Synthesized α-Galactooligosaccharides and Evaluation of the Structure-Activity Relationship

In this study, α-galactooligosaccharides (α-GOSs) were synthesized using galactose as the substrate and α-galactosidase from Aspergillus niger as the catalyst. In the reaction, synthesized products of U1, U2, U3, and U4 were detected by high-performance liquid chromatography. By mass spectrometry, nuclear magnetic resonance, and 1-phenyl-3-methyl-5-pyrazolone derivatization, U1 was the mixture of disaccharides of α-d-Gal p-(1→1)-α-d-Gal, α-d-Gal p-(1→2)-α-d-Gal, α-d-Gal p-(1→3)-α-d-Gal, α-d-Gal p-(1→4)-α-d-Gal, U2 was identified to be α-d-Gal p-(1→6)-α-d-Gal, U3 was the mixture of galactotrisaccharides linked by one α-(1→6)-glycosidic linkage and one other α-glycosidic linkage, and U4 was identified as α-d-Gal p-(1→6)-α-d-Gal p-(1→6)-α-d-Gal. Afterward, the synthesized α-GOSs (U1, U2, U3, U4, and their mixture) as well as α-GOSs (manninotriose, stachyose, ciceritol, and verbascose) obtained from natural materials were used as subjects to evaluate their immunomodulatory effects in vitro by culturing mouse macrophage RAW264.7 cells. The results showed that α-GOS with a higher degree of polymerization had better immunomodulatory activity, while to a certain extent, α-GOS linked with α-(1→6)-galactosidic linkage showed a better immunomodulatory effect.

Composition and metabolism of fecal microbiota from normal and overweight children are differentially affected by melibiose, raffinose and raffinose-derived fructans

The aim of the study was to investigate the metabolism of non-digestible oligo- and polysaccharides by fecal microbiota, using isothermal microcalorimetry. The five tested substrates were raffinose, melibiose, a mixture of oligo- and polysaccharides produced from raffinose by levansucrase, levan synthesized from raffinose, and levan from timothy grass. Two inocula were comprised of pooled fecal samples from overweight or normal-weight children, from healthy adult volunteers and a pure culture of Bacteroides thetaiotaomicron as a reference bacterium for colon microbiota. The growth was analyzed based on the heat evolution curves, and the production of organic acids and gases. Taxonomic profiles of the microbiota were assessed by 16S rDNA sequencing. Raffinose and melibiose promoted the growth of bifidobacteria in all fecal pools. Several pool-specific substrate-related responses to raffinose and melibiose were revealed. Lactate-producing bacteria (Streptococcus and Enterococcus) became enriched in the pool of overweight children resulting in lactic acid as the major fermentation product on short saccharides. Acetic and butyric acids were prevalent at fermentation in the normal-weight pool coinciding with the enrichment of Catenibacterium. In the adult pool, the specific promotion of Bacteroides and Lachnospiraceae by levans was disclosed. In the fecal pool of normal-weight children, levans stimulated the growth of Senegalimassilia and Lachnoclostridium and this particular pool also showed the highest maximum heat production rate at levan fermentation. Levans and raffinose-derived oligosaccharides, but not raffinose and melibiose were completely fermented by a pure culture of Bacteroides thetaiotaomicron. The main conclusion from the study is that fecal microbiota of normal and overweight children have different compositions and they respond in specific manners to non-digestible oligo- and polysaccharides: raffinose, melibiose, raffinose-derived oligosaccharides and levans. The potential of the tested saccharides to support a healthy balance of colon microbiota requires further studies.

Bacterial Cellulose Relieves Diphenoxylate-Induced Constipation in Rats

This study was to probe the effects of bacterial cellulose (BC) on diphenoxylate-induced constipation in rats. Administration with BC at 500 mg/kg of body weight in diphenoxylate-induced constipation rats distinctly improved the carmine propulsion rate (83.5 ± 5.2%), shortened the defecating time of the first red feces (249.0 ± 23.3 min), and increased the weight of carmine red feces within 5 h (2.7 ± 1.3 g). The levels of aquaporins (AQP-2, AQP-3, and AQP-4) and inhibitory neurotransmitters (nitric oxide, nitric oxide synthetase, vasoactive intestinal peptide, and arginine vasopressin) in the BC-treated groups reduced by 31.9-40.0% ( p < 0.01) and 21.1-67.7% ( p < 0.01) compared to those in the constipation group, respectively. However, the secretion of excitability neurotransmitters (substance P and motilin) in the BC-treated groups was increased by 20.0-39.9% ( p < 0.01). The activities of ATPases in the colon of constipation rats were significantly weakened by BC administration ( p < 0.01). Histological morphology of the colon showed that BC supplementation could effectively increase the length of villus cells and the thickness of colonic mucosa and muscle ( p < 0.01). Moreover, BC supplementation could protect colonic smooth muscle cells against apoptosis. All of the findings suggest that BC supplementation effectively relieves constipation in rats and BC would be used as a great promising dietary fiber for alleviating constipation.

Stachyose Improves Inflammation through Modulating Gut Microbiota of High-Fat Diet/Streptozotocin-Induced Type 2 Diabetes in Rats

SCOPE

The present study is undertaken to assess the effects of stachyose (STS) on type 2 diabetes in rats and changes in the gut microbiota compared to metformin (MET).

METHODS AND RESULTS

The type 2 diabetic model is successfully established via a high-fat diet /streptozotocin in Wistar rats, and STS or MET is administered for 4 weeks. Blood is collected to analyze biochemical parameters, pancreas for mRNA expression of related gene, and contents of colon for gut microbiota. STS or MET decreases serum LPS, mRNA expression of IL-6, and tumor necrosis factor-α (TNF-α). In addition, STS and MET show a similar shifting of the structure of the gut microbiota and a selective enrichment of key species. At the genus level, STS shows selective enrichment of Phascolarctobacterium, Bilophila, Oscillospira, Turicibacter, and SMB5, but MET demonstrates a selective effect on Sutterella, Prevotella, 02d06, and rc4. The correlation analysis indicates that STS and MET decrease IL-6 and TNF-α and increase Akt/PI3K expression, which are relative to key species of gut microbiota.

CONCLUSION

STS decreases pancreatic mRNA expression of IL-6 and TNF-α via key species of gut microbiota. The mechanism of this effect is similar to that of MET.