Potential interventions and interactions of bioactive polyphenols and functional polysaccharides to alleviate inflammatory bowel disease - A review.

Inflammatory bowel disease is a multifaceted condition that is influenced by nutritional, microbial, environmental, genetic, psychological, and immunological factors. Polyphenols and polysaccharides have gained recognition for their therapeutic potential. This review emphasizes the biological effects of polyphenols and polysaccharides, and explores their antioxidant, anti-inflammatory, and microbiome-modulating properties in the management of inflammatory bowel disease (IBD). However, polyphenols encounter challenges, such as low stability and low bioavailability in the colon during IBD treatment. Hence, polysaccharide-based encapsulation is a promising solution to achieve targeted delivery, improved bioavailability, reduced toxicity, and enhanced stability. This review also discusses the significance of covalent and non-covalent interactions, and simple and complex encapsulation between polyphenols and polysaccharides. The administration of these compounds in appropriate quantities has proven beneficial in preventing the development of Crohn's disease and ulcerative colitis, ultimately leading to the management of IBD. The use of polyphenols and polysaccharides has been found to reduce histological scores and colon injury associated with IBD, increase the abundance of beneficial microbes, inhibit the development of colitis-associated cancer, promote the production of microbial end-products, such as short-chain fatty acids (SCFAs), and improve anti-inflammatory properties. Despite the combined effects of polyphenols and polysaccharides observed in both in vitro and in vivo studies, further human clinical trials are needed to comprehend their effectiveness on inflammatory bowel disease.

RG-I pectic polysaccharides and hesperidin synergistically modulate gut microbiota: An in vitro study targeting the proportional relationship.

In this study, we investigated how different proportions blends of Rhamnogalacturonan-I pectic polysaccharides and hesperidin impact the gut microbiota and metabolites using an in vitro simulated digestion and fermentation model. The results indicated that both of them could modulate the gut microbiota and produce beneficial metabolites. However, their blends in particular proportions (such as 1:1) exhibited remarkable synergistic effects on modulating the intestinal microenvironment, surpassing the effects observed with individual components. Specifically, these blends could benefit the host by increasing short-chain fatty acids production (such as acetate), improving hesperidin bioavailability, producing more metabolites (such as hesperetin, phenolic acids), and promoting the growth of beneficial bacteria. This synergistic and additive effect was inseparable from the role of gut microbiota. Certain beneficial bacteria, such as Blautia, Faecalibacterium, and Prevotella, exhibited strong preferences for those blends, thereby contributing to host health through participating in carbohydrate and flavonoid metabolism.

Uncovering the pharmacological mechanisms of Patchouli essential oil for treating ulcerative colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Pogostemonis Herba has long been used in traditional Chinese medicine to treat inflammatory disorders. Patchouli essential oil (PEO) is the primary component of Pogostemonis Herba, and it has been suggested to offer curative potential when applied to treat ulcerative colitis (UC). However, the pharmacological mechanisms of PEO for treating UC remain to be clarified. AIM OF THE STUDY: To elucidate the pharmacological mechanisms of PEO for treating UC. METHODS AND RESULTS: In the present study, transcriptomic and network pharmacology approaches were combined to clarify the mechanisms of PEO for treating UC. Our results reveal that rectal PEO administration in UC model mice significantly alleviated symptoms of UC. In addition, PEO effectively suppressed colonic inflammation and oxidative stress. Mechanistically, PEO can ameliorate UC mice by modulating gut microbiota, inhibiting inflammatory targets (OPTC, PTN, IFIT3, EGFR, and TLR4), and inhibiting the PI3K-AKT pathway. Next, the 11 potential bioactive components that play a role in PEO's anti-UC mechanism were identified, and the therapeutic efficacy of the pogostone (a bioactive component) in UC mice was partially validated. CONCLUSION: This study highlights the mechanisms through which PEO can treat UC, providing a rigorous scientific foundation for future efforts to develop and apply PEO for treating UC.

Uncovering the mechanisms of Zhubi decoction against rheumatoid arthritis through an integrated study of network pharmacology, metabolomics, and intestinal flora.

ETHNOPHARMACOLOGICAL RELEVANCE: Zhubi Decoction (ZBD) is a modified formulation derived from the classic traditional Chinese medicine prescription "Er-Xian Decoction" documented in the esteemed "Clinical Manual of Chinese Medical Prescription". While the utilization of ZBD has exhibited promising clinical outcomes in treating rheumatoid arthritis (RA), the precise bioactive chemical constituents and the underlying mechanisms involved in its therapeutic efficacy remain to be comprehensively determined. AIM OF THE STUDY: This study aims to systematically examine ZBD's pharmacological effects and molecular mechanisms for RA alleviation. MATERIALS AND METHODS: Utilizing the collagen-induced arthritis (CIA) rat model, we comprehensively evaluated the anti-rheumatoid arthritis effects of ZBD in vivo through various indices, such as paw edema, arthritis index, ankle diameter, inflammatory cytokine levels, pathological conditions, and micro-CT analysis. The UPLC-MS/MS technique was utilized to analyze the compounds of ZBD. The potential therapeutic targets and signaling pathways of ZBD in the management of RA were predicted using network pharmacology. To analyze comprehensive metabolic profiles and identify underlying metabolic pathways, we conducted a serum-based widely targeted metabolomics analysis utilizing LC-MS technology. Key targets and predicted pathways were further validated using immunofluorescent staining, which integrated findings from serum metabolomics and network pharmacology analysis. Additionally, we analyzed the gut microbiota composition in rats employing 16 S rDNA sequencing and investigated the effects of ZBD on the microbiota of CIA rats through bioinformatics and statistical methods. RESULTS: ZBD exhibited remarkable efficacy in alleviating RA symptoms in CIA rats without notable side effects. This included reduced paw redness and swelling, minimized joint damage, improved the histopathology of cartilage and synovium, mitigated the inflammatory state, and lowered serum concentrations of cytokines TNF-α, IL-1ß and IL-6. Notably, the effectiveness of ZBD was comparable to MTX. Network pharmacology analysis revealed inflammation and immunity-related signaling pathways, such as PI3K/AKT, MAPK, IL-17, and TNF signaling pathways, as vital mediators in the effectual mechanisms of ZBD. Immunofluorescence analysis validated ZBD's ability to inhibit PI3K/AKT pathway proteins. Serum metabolomics studies revealed that ZBD modulates 170 differential metabolites, partially restored disrupted metabolic profiles in CIA rats. With a notable impact on amino acids and their metabolites, and lipids and lipid-like molecules. Integrated analysis of metabolomics and network pharmacology identified 6 pivotal metabolite pathways and 3 crucial targets: PTGS2, GSTP1, and ALDH2. Additionally, 16 S rDNA sequencing illuminated that ZBD mitigated gut microbiota dysbiosis in the CIA group, highlighting key genera such as Ligilactobacillus, Prevotella_9, unclassified_Bacilli, and unclassified_rumen_bacterium_JW32. Correlation analysis disclosed a significant link between 47 distinct metabolites and specific bacterial species. CONCLUSION: ZBD is a safe and efficacious TCM formulation, demonstrates efficacy in treating RA through its multi-component, multi-target, and multi-pathway mechanisms. The regulation of inflammation and immunity-related signaling pathways constitutes a crucial mechanism of ZBD's efficacy. Furthermore, ZBD modulates host metabolism and intestinal flora. The integrated analysis presents experimental evidence of ZBD for the management of RA.

A novel antidepressant homogeneous polysaccharide YLP-1 from Millettia pulchra ameliorates tryptophan metabolism and SCFAs through modulating gut microbiota.

The root of Millettia pulchra (YLS) has been traditionally used as a folk medicine for the treatment of depression and insomnia in the Zhuang nationality of China, and its polysaccharides have potential antidepressant effect. In this study, a novel homogeneous polysaccharide (YLP-1) was purified from the crude polysaccharides of YLS, and it is mainly composed of glucose, arabinose and mannose with molar ratio of 87.25%, 10.77%, and 1.98%, respectively. YLP-1 is a novel α-glucan with the backbone of 1,4-Glcp and branched at C6 of 1,4,6-Glcp to combine 1,4-Manp and 1,5-Araf. The microstructure of YLP-1 displayed a uniform ellipsoidal-like chain morphology and dispersed uniformly in solution. YLP-1 effectively ameliorated depression-like ethological behaviors and restored the decreased catecholamine levels in chronic variable stress (CVS)-induced depression rats. Additionally, it significantly improved the disturbance of gut microbiota induced by CVS stimuli, particularly affecting bacteria that produce short-chain fatty acids (SCFAs), such as bacteria species Lactobacillus spp.. In vitro fermentation study further confirmed that YLP-1 intake could promote SCFAs production by Lactobacillus spp. YLP-1 also mitigated the disruption of tryptophan metabolites in urine and serum. These findings provide evidences for the further development of YLP-1 as a macromolecular antidepressant drug.

Grifola frondosa polysaccharide's therapeutic potential in oxazolone-induced ulcerative colitis.

Grifola frondosa polysaccharide (GFP) is a consumable fungus recognized for its potential health advantages. The present study aimed to investigate the development and potential etiologies of ulcerative colitis (UC) utilizing oxazolone (OXZ) as an inducer in mice, along with assessing the therapeutic effects of GFP at varying doses in UC mice, with sulfasalazine (SASP) serving as the positive control. The obtained results indicated that OXZ intervention in mice induced numerous physical manifestations of UC, including increased disease activity index (DAI), decreased goblet cell division, enhanced fibrosis, reduced expression of Claudin1 and Zona encludens protein1 (ZO-1), decreased proliferative activity of colonic mucosal epithelial cells, disturbed oxidation balance, and alterations in intestinal flora. Nonetheless, GFP intervention significantly ameliorated or even resolved these abnormal indicators to a considerable extent. Consequently, this study suggests that GFP might serve as a prebiotic to regulate intestinal flora, mitigate enterotoxin production, restore oxidative balance, thereby reducing the generation of inflammatory mediators, restoring the intestinal barrier, and ultimately improving OXZ-induced UC in mice. GFP demonstrates promising potential as a candidate drug for colitis treatment and as a dietary supplement for alleviating intestinal inflammatory issues.

A fructan-type garlic polysaccharide upregulates immune responses in macrophage cells and in immunosuppressive mice.

The anti-inflammatory effects of plant polysaccharides are well known. However, the stimulatory effects of polysaccharides under immunosuppressive conditions and their link with the polysaccharide structure is underexplored. In this work, the immune modulatory effects of a garlic polysaccharide (GP) are investigated via in vitro and vivo methods. It is observed that GP enhance the immune response of macrophages (RAW264.7) as indicated by the elevated levels of nitric oxide, TNF-α and IL-6. The observation that GP are able to stimulate the immune response in vitro was then explored with the use of an immunosuppressed mouse model. Surprisingly, GP exhibited dose-dependent up-regulatory impacts on the cyclophosphamide (CTX) suppressed levels of cytokines such as IFN-γ and IL-6 and immunoglobulins (e.g. IgA and IgG). The GP intervention reversed histopathological damage to the small intestine and spleen and increased fecal short-chain fatty acid levels. Moreover, GP modulates the gut microbiota dysbiosis by increasing the abundance of immunogenic bacteria such as g__norank_f__Erysipelotrichaceae, while inhibiting the over-abundance of g_Bacteroides. Functional predictions indicated that gut biomarkers of GP possessed the functions of glycoside hydrolase family 32 (GH32) and ß-fructofuranosidase. It is concluded that GP is a promising immunostimulant for immune-compromised individuals.

Oat ß-(1 → 3, 1 → 4)-d-glucan alleviates food allergy-induced colonic injury in mice by increasing Lachnospiraceae abundance and butyrate production.

Oat ß-(1 â†’ 3, 1 â†’ 4)-d-glucan (OBG), a linear polysaccharide primarily found in oat bran, has been demonstrated to possess immunomodulatory properties and regulate gut microbiota. This study aimed to investigate the impact of low molecular weight (Mw) OBG (155.2 kDa) on colonic injury and allergic symptoms induced by food allergy (FA), and to explore its potential mechanism. In Experiment 1, results indicated that oral OBG improved colonic inflammation and epithelial barrier, and significantly relieved allergy symptoms. Importantly, the OBG supplement altered the gut microbiota composition, particularly increasing the abundance of Lachnospiraceae and its genera, and promoted the production of short-chain fatty acids, especially butyrate. However, in Experiment 2, the gut microbial depletion eliminated these protective effects of OBG on the colon in allergic mice. Further, in Experiment 3, fecal microbiota transplantation and sterile fecal filtrate transfer directly validated the role of OBG-mediated gut microbiota and its metabolites in relieving FA and its induced colonic injury. Our findings suggest that low Mw OBG can alleviate FA-induced colonic damage by increasing Lachnospiraceae abundance and butyrate production, and provide novel insights into the health benefits and mechanisms of dietary polysaccharide intervention for FA.

The Effects of 1-Kestose on the Abundance of Inflammation-Related Gene mRNA in Adipose Tissue and the Gut Microbiota Composition in Rats Fed a High-Fat Diet.

Chronic inflammation in adipose tissue is thought to contribute to insulin resistance, which involves the gut microbiota. Our previous studies have demonstrated that ingestion of 1-kestose can alter the gut microbiota composition, increase cecal butyrate levels, and improve insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Additionally, we found that 1-kestose supplementation ameliorated insulin resistance in obese rat models fed a high-fat diet (HFD), although the effects of 1-kestose on the abundance of inflammation-related gene in adipose tissue and gut microbiota composition in these rats were not explored. This study aimed to investigate the impact of 1-kestose on these parameters in HFD-fed rats, compared to OLETF rats. Male Sprague-Dawley rats were divided into two dietary groups, control or HFD, for 19 wk. Each group was further subdivided to receive either tap water or tap water supplemented with 2% (w/v) 1-kestose throughout the study. We evaluated gene expression in adipose tissue, as well as short-chain fatty acids (SCFAs) levels and microbial composition in the cecum contents. 1-Kestose intake restored the increased relative abundance of tumor necrosis factor (Tnf) mRNA in adipose tissue and the reduced level of butyrate in the cecum contents of HFD-fed rats to those observed in control diet-fed rats. Additionally, 1-kestose consumption changed the composition of the gut microbiota, increasing Butyricicoccus spp., decreasing UGC-005 and Streptococcus spp., in the cecum contents of HFD-fed rats. Our findings suggest that 1-kestose supplementation reduces adipose tissue inflammation and increases butyrate levels in the gut of HFD-fed rats, associated with changes in the gut microbiota composition, distinct from those seen in OLETF rats.

The Intake of Dietary Lipids Improves Glucose Tolerance via Modulating Gut Microbiota.

The composition of gut microbiota is determined not only by genetic factors but also by environmental factors, such as diet, exercise, and disease conditions. Among these factors, diet is crucial in changing the gut microbial composition. Dietary lipids composed of different fatty acids not only alter host metabolism but also have a significant impact on the composition of gut microbiota. However, the molecular mechanisms underlying the relationship between these host effects and their impact on gut microbiota remain unclear. Here, we demonstrated that intake of different dietary lipids improved glucose tolerance by modulating gut microbiota. The results of our analysis show that the taxa of bacteria that increase in number as a result of dietary lipid intake play an important role in glucose metabolism. Thus, we have identified a new mechanism underlying the function of dietary lipids in regulating glucose homeostasis. Our findings contribute to possible new methods to prevent and treat metabolic disorders by modifying the composition of gut microbiota.

[Research progress on the relationship between the gut microbiota dysbiosis and sepsis-induced cardiomyopathy].

Sepsis is a life-threatening organ dysfunction caused by the host's dysfunctional response to infection. Sepsis-induced cardiomyopathy (SICM), as a serious complication of sepsis, is an acute reversible cardiac dysfunction syndrome unrelated to myocardial ischemia, which affects the outcome and prognosis of sepsis. As a complex microbial system, gut microbiota has been confirmed to be involved in the development of coronary heart disease, hypertension, heart failure and other cardiovascular diseases, and is also related to the occurrence and development of sepsis. However, there are few studies on the relationship between gut microbiota and SICM. This paper reviews the current research progress on gut microbiota and SICM, aiming at provide a new idea for clinical treatment of SICM.

Gut redox and microbiome: charting the roadmap to T-cell regulation.

The gastrointestinal (GI) tract redox environment, influenced by commensal microbiota and bacterial-derived metabolites, is crucial in shaping T-cell responses. Specifically, metabolites from gut microbiota (GM) exhibit robust anti-inflammatory effects, fostering the differentiation and regulation of CD8+ tissue-resident memory (TRM) cells, mucosal-associated invariant T (MAIT) cells, and stabilizing gut-resident Treg cells. Nitric oxide (NO), a pivotal redox mediator, emerges as a central regulator of T-cell functions and gut inflammation. NO impacts the composition of the gut microbiome, driving the differentiation of pro-inflammatory Th17 cells and exacerbating intestinal inflammation, and supports Treg expansion, showcasing its dual role in immune homeostasis. This review delves into the complex interplay between GI redox balance and GM metabolites, elucidating their profound impact on T-cell regulation. Additionally, it comprehensively emphasizes the critical role of GI redox, particularly reactive oxygen species (ROS) and NO, in shaping T-cell phenotype and functions. These insights offer valuable perspectives on disease mechanisms and potential therapeutic strategies for conditions associated with oxidative stress. Understanding the complex cross-talk between GI redox, GM metabolites, and T-cell responses provides valuable insights into potential therapeutic avenues for immune-mediated diseases, underscoring the significance of maintaining GI redox balance for optimal immune health.

Evaluation of efficacy and safety of Lacticaseibacillus rhamnosus LRa05 in the eradication of Helicobacter pylori: a randomized, double-blind, placebo-controlled trial.

Aim: This study aims to evaluate the efficacy of Lacticaseibacillus rhamnosus LRa05 supplementation in enhancing Helicobacter pylori (H. pylori) eradication rate and alleviating the gastrointestinal side effects associated with bismuth quadruple therapy. Methods: H. pylori-positive patients were randomized to receive levofloxacin-based bismuth quadruple therapy combined either probiotic LRa05 or a placebo for two weeks, followed by LRa05 (1 × 1010 CFU) or maltodextrin for the next two weeks. H. pylori infection was detected by 13C breath test pre- and post-treatment. Blood and stool samples were collected at week 0 and week 4 for routine and biochemical analysis, and serum inflammatory markers. Gastrointestinal symptoms were evaluated using the gastrointestinal symptom rating scale (GSRS). Intestinal microbiota was analyzed using 16S rRNA sequencing. The research was listed under the Chinese Clinical Trial Registry (ChiCTR2300072220), and written informed consent was obtained from all participants. Results: The LRa05 group exhibited a trend toward higher H. pylori eradication rates (86.11%) compared to the placebo group (82.86%), though the difference was not statistically significant. Significant reductions in neutrophil count, alanine aminotransferase, aspartate aminotransferase, pepsinogen I, interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) (p < 0.05) suggest that LRa05 supplementation may mitigate inflammation, enhance liver function, and potential aid in early cancer prevention. GSRS symptom scores showed that LRa05 alleviated abdominal pain, acid reflux, bloating, and diarrhea, enhancing patient compliance. Furthermore, 16S rRNA sequencing showed that LRa05 countered the antibiotic-induced disruption of gut microbiota diversity, primarily by increasing beneficial bacteria. Conclusion: Although LRa05 did not significantly improve the success rate of H. pylori eradication therapy, it has the potential to improve liver function and reduced levels of inflammatory markers such as IL-6 and TNF-α in the body, regulating the inflammatory response. In addition, it played a positive role in alleviating the adverse symptoms and gut microbiota disturbances caused by eradication therapy, providing a possible way to improve the overall health of patients and demonstrating promising clinical potential. Clinical Trial Registration: http://www.chictr.org.cn, identifier ChiCTR2300072220.

Gut microbial subtypes and clinicopathological value for colorectal cancer.

BACKGROUND: Gut bacteria are related to colorectal cancer (CRC) and its clinicopathologic characteristics. OBJECTIVE: To develop gut bacterial subtypes and explore potential microbial targets for CRC. METHODS: Stool samples from 914 volunteers (376 CRCs, 363 advanced adenomas, and 175 normal controls) were included for 16S rRNA sequencing. Unsupervised learning was used to generate gut microbial subtypes. Gut bacterial community composition and clustering effects were plotted. Differences of gut bacterial abundance were analyzed. Then, the association of CRC-associated bacteria with subtypes and the association of gut bacteria with clinical information were assessed. The CatBoost models based on gut differential bacteria were constructed to identify the diseases including CRC and advanced adenoma (AA). RESULTS: Four gut microbial subtypes (A, B, C, D) were finally obtained via unsupervised learning. The characteristic bacteria of each subtype were Escherichia-Shigella in subtype A, Streptococcus in subtype B, Blautia in subtype C, and Bacteroides in subtype D. Clinical information (e.g., free fatty acids and total cholesterol) and CRC pathological information (e.g., tumor depth) varied among gut microbial subtypes. Bacilli, Lactobacillales, etc., were positively correlated with subtype B. Positive correlation of Blautia, Lachnospiraceae, etc., with subtype C and negative correlation of Coriobacteriia, Coriobacteriales, etc., with subtype D were found. Finally, the predictive ability of CatBoost models for CRC identification was improved based on gut microbial subtypes. CONCLUSION: Gut microbial subtypes provide characteristic gut bacteria and are expected to contribute to the diagnosis of CRC.

Gut microbiota as an efficacy marker of surgical treatment of obesity.

OBJECTIVE: Aim: To study the impact of bariatric interventions on changes in the parameters of the intestinal microbiome. PATIENTS AND METHODS: Materials and Methods: The research method is a prospective observational cohort monocentric study. 112 patients were included in the study. All patients had indications for surgical obesity treatment due to IFSO criteria. All patients were offered surgical treatment. 53 patients who consented to the operation formed the study group. 59 patients who refused surgical treatment formed the control group. The result of the study was evaluated one year after the start of treatment. The studied group of patients underwent bariatric interventions. The control group consisted of 59 obese patients who were treated conservatively. RESULTS: Results: evaluating criteria was: %EWL (percentage of excess weight loss), comorbidity regression, life quality improvement. Overwhelming majority of surgically treated patients with gut microbiome composition improvement reached %EWL≥50. Patients who didn't have improvements in gut microbiota composition had insufficient efficacy of surgical treatment. CONCLUSION: Conclusions: 1) Surgical treatment of obesity leads to the positive changes in the gut microbiota. 2) Operated patients, who had positive dynamics in changes of gut microbiota demonstrated sufficient efficacy of surgical treatment due to %EWL. 3) Firmicutes/Bacteriodetes ratio and Bacterioidetes/Faecalibacterium ratio can be one of the criteria of the efficacy of surgical treatment of obesity. 4) Patients of the control group, had positive dynamics of changes in gut microbiota much rarely than operated patients and the effectiveness of obesity treatment was insufficient.

Unveiling the Intricate Link Between Anaerobe Niche and Alzheimer Disease Pathogenesis.

Dysbiosis within microbiomes has been increasingly implicated in many systemic illnesses, such as cardiovascular disease, metabolic syndrome, respiratory infections, and Alzheimer disease (Ad). The correlation between Ad and microbial dysbiosis has been repeatedly shown, yet the etiologic cause of microbial dysbiosis remains elusive. From a neuropathology perspective, abnormal (often age-related) changes in the brain, associated structures, and bodily lumens tend toward an accumulation of oxygen-depleted pathologic structures, which are anaerobically selective niches. These anaerobic environments may promote progressive change in the microbial community proximal to the brain and thus deserve further investigation. In this review, we identify and explore what is known about the anaerobic niche near or associated with the brain and the anaerobes that it is harbors. We identify the anaerobe stakeholders within microbiome communities and the impacts on the neurodegenerative processes associated with Ad. Chronic oral dysbiosis in anaerobic dental pockets and the composition of the gut microbiota from fecal stool are the 2 largest anaerobic niche sources of bacterial transference to the brain. At the blood-brain barrier, cerebral atherosclerotic plaques are predominated by anaerobic species intimately associated with the brain vasculature. Focal cerebritis/brain abscess and corpora amylacea may also establish chronic anaerobic niches in direct proximity to brain parenchyma. In exploring the anaerobic niche proximal to the brain, we identify research opportunities to explore potential sources of microbial dysbiosis associated with Ad.

Temperament in Early Childhood Is Associated With Gut Microbiota Composition and Diversity.

Temperament is a key predictor of human mental health and cognitive and emotional development. Although human fear behavior is reportedly associated with gut microbiome in infancy, infant gut microbiota changes dramatically during the first 5 years, when the diversity and composition of gut microbiome are established. This period is crucial for the development of the prefrontal cortex, which is involved in emotion regulation. Therefore, this study investigated the relationship between temperament and gut microbiota in 284 preschool children aged 3-4 years. Child temperament was assessed by maternal reports of the Children's Behavior Questionnaire. Gut microbiota (alpha/beta diversity and genera abundance) was evaluated using 16S rRNA sequencing of stool samples. A low abundance of anti-inflammatory bacteria (e.g., Faecalibacterium) and a high abundance of pro-inflammatory bacteria (e.g., Eggerthella, Flavonifractor) were associated with higher negative emotionality and stress response (i.e., negative affectivity, ß = -0.17, p = 0.004) and lower positive emotionality and reward-seeking (i.e., surgency/extraversion, ß = 0.15, p = 0.013). Additionally, gut microbiota diversity was associated with speed of response initiation (i.e., impulsivity, a specific aspect of surgency/extraversion, ß = 0.16, p = 0.008). This study provides insight into the biological mechanisms of temperament and takes important steps toward identifying predictive markers of psychological/emotional risk.

Highly accurate and sensitive absolute quantification of bacterial strains in human fecal samples.

BACKGROUND: Next-generation sequencing (NGS) approaches have revolutionized gut microbiome research and can provide strain-level resolution, but these techniques have limitations in that they are only semi-quantitative, suffer from high detection limits, and generate data that is compositional. The present study aimed to systematically compare quantitative PCR (qPCR) and droplet digital PCR (ddPCR) for the absolute quantification of Limosilactobacillus reuteri strains in human fecal samples and to develop an optimized protocol for the absolute quantification of bacterial strains in fecal samples. RESULTS: Using strain-specific PCR primers for L. reuteri 17938, ddPCR showed slightly better reproducibility, but qPCR was almost as reproducible and showed comparable sensitivity (limit of detection [LOD] around 104 cells/g feces) and linearity (R2 > 0.98) when kit-based DNA isolation methods were used. qPCR further had a wider dynamic range and is cheaper and faster. Based on these findings, we conclude that qPCR has advantages over ddPCR for the absolute quantification of bacterial strains in fecal samples. We provide an optimized and easy-to-follow step-by-step protocol for the design of strain-specific qPCR assays, starting from primer design from genome sequences to the calibration of the PCR system. Validation of this protocol to design PCR assays for two L. reuteri strains, PB-W1 and DSM 20016 T, resulted in a highly accurate qPCR with a detection limit in spiked fecal samples of around 103 cells/g feces. Applying our strain-specific qPCR assays to fecal samples collected from human subjects who received live L. reuteri PB-W1 or DSM 20016 T during a human trial demonstrated a highly accurate quantification and sensitive detection of these two strains, with a much lower LOD and a broader dynamic range compared to NGS approaches (16S rRNA gene sequencing and whole metagenome sequencing). CONCLUSIONS: Based on our analyses, we consider qPCR with kit-based DNA extraction approaches the best approach to accurately quantify gut bacteria at the strain level in fecal samples. The provided step-by-step protocol will allow scientists to design highly sensitive strain-specific PCR systems for the accurate quantification of bacterial strains of not only L. reuteri but also other bacterial taxa in a broad range of applications and sample types. Video Abstract.

Age and environment are the main drivers shaping the wild common sole (Solea solea) microbiota.

Microbiota plays an essential role in fish growth and health and may be influenced by the changing environmental conditions. Here, we explored the microbiota of wild common sole, one of the most important fishery resources in the Mediterranean Sea, collected from different areas in the North Adriatic Sea. Our results show that the sole microbiota differs from that of the surrounding environment and among the different body sites (gill, skin and gut). Gut microbiota composition showed to be strongly related to fish age, rather than maturity, sex or sampling site. Age-related shifts in gut microbial communities were identified, with increased abundances of Bacteroidia and Desulfobacteria, unveiling potential microbial proxies for age estimation crucial for fisheries management. Our results expand the limited knowledge of the wild common sole microbiota, also in the light of the potential usefulness of the fish microbiota as a tool for future stock identification and connectivity studies.

Prebiotic effects of commercial apple juice in high-fat diet fed rat.

OBJECTIVES: Apples are one of the most frequently consumed fruits and are effective in preventing lifestyle-related and other diseases. However, few studies have been conducted to evaluate health benefits of processed apple products such as juice. In this study, we analyzed the health benefits of consuming apple juice, focusing on changes in the gut microbiota, which plays an important role in maintaining human health. RESULTS: Rats were fed apple juice ad libitum, and the relative abundances of various gut microbiota in fecal samples were analyzed. In addition, rats treated apple juice were fed with a high-fat diet, and body weight, plasma triglyceride, glucose, and cholesterol levels were measured. The relative abundance of Clostridium cluster XIV did not change with the treatment of apple juice, but the relative abundance of Clostridium cluster IV was significantly decreased. In contrast, the relative abundances of Lactobacillus and Bifidobacterium, which provide benefits to the human body, were significantly increased by 3-fold and 10-fold, respectively, with apple juice consumption. When apple juice-treated rats were fed a high-fat diet, the increase in body weight, liver fat, and blood lipid parameters were all suppressed compared to high-fat alone group. CONCULUSION: This study suggests that the consumption of apple juice changes the gut microbiota, exerts a prebiotic effect, and is effective in improving lifestyle-related diseases.