Like Cures Like: Pharmacological Activity of Anti-Inflammatory Lipopolysaccharides From Gut Microbiome

Linking gastrointestinal tract structure, function, and gene expression signatures to growth variability in broilers: a novel interpretation for flock uniformity

Variation in body weight (BW) within broiler flocks is a significant challenge in poultry production. Investigating differences in gut-related parameters between low (LBW) and high BW (HBW) chicks may provide insights into the underlying causes of BW heterogeneity. 908 day-old male broiler chicks were reared until d 7 and then ranked into LBW and HBW groups. Thereafter, performance parameters were compared between BW groups periodically. On d 7, 14, and 38, visceral organ characteristics, intestinal permeability, and duodenal and ileal histomorphology were examined. Expression profiles were analyzed for 79 ileal genes related to gut barrier function, immune function, nutrient transport, gut hormones, nutrient receptors, metabolism, and oxidation using high-throughput qPCR. Student's t-tests were performed to compare measurements. Multivariate statistics, including partial least square regression (PLSR) analysis, were applied to identify combinations of key genes discriminating BW groups, offering predictive capability for phenotypic variations. The HBW group remained heavier at each timepoint, which could be explained by higher feed intake. The HBW group had shorter relative small intestine length but higher villus height and villi height/crypt depth ratios. The LBW group demonstrated increased intestinal permeability on d 38. The LBW group showed upregulation of immune response genes including TNF-α on d 7 and CYP450 on d 38, while the HBW group showed higher AHSA1 and HSPA4 expressions on d 7. The LBW group had upregulation of the metabolism genes mTOR and EIF4EBP1 on d 7 and the satiety-induced hormone cholecystokinin on d 14, while the HBW group tended to increase expression of the hunger hormone ghrelin on d 38. Genes related to gut barrier function, nutrient transport, and oxidation categories were consistently upregulated in the HBW group. PLSR models revealed 4, 12, and 11 sets of key genes highly predictive of BW phenotypes on d 7, 14, and 38, respectively. These findings suggest that growth rates are linked to the intestinal size, structure, and function of broiler chickens, offering insights into the underlying mechanisms regulating BW.

Microbiota transfer early after birth modulates genetic susceptibility to chronic arthritis in mice

Genetics is central to the susceptibility or resistance to autoimmunity, and mounting evidence indicates that the intestinal microbiota also plays an essential role. In murine arthritis models, short-chain fat acid supplementation reduces disease severity by modulating tryptophan-metabolizing bacteria. Common microbiota transfer methods modulate arthritis severity, however, they are not practical for chronic models such as pristane-induced arthritis (PIA). PIA-resistant (HIII) and PIA-susceptible (LIII) mice harbor diverse intestinal microbiomes, which might be implicated in their divergent susceptibility. To investigate this hypothesis, we used cross-fostering to stably transfer the microbiota. In this study, we show that extreme susceptibility to arthritis can be modulated by early microbiota transfer, with long-lasting effects. HIII and LIII pups were cross-fostered and injected with pristane after weaning. PIA severity in cross-fostered LIII mice was significantly reduced in the chronic phase. Metagenomic analyses showed that HIII and LIII microbiomes were partly shifted by cross-fostering. Microbial groups whose abundance was associated with either HIII or LIII mice presented similar composition in cross-fostered mice of the opposite strains, suggesting a role in PIA susceptibility. Identification of bacterial groups that modulate chronic arthritis will contribute novel insights on the pathogenesis of human rheumatoid arthritis and targets for replication and functional studies.

Polycystic ovary syndrome: Insights into its prevalence, diagnosis, and management with special reference to gut microbial dysbiosis

Polycystic ovary syndrome (PCOS) represents major endocrine and metabolic disorder among women largely characterized by hyperandrogenism and oligomenorrhea precipitates serious complications such as type 2 diabetes, early atherosclerosis, infertility, and endometrial cancer. Several etiological theories were proposed to define the exact cause of the PCOS, which is characterized, by the hypothalamic-pituitary axis, ovarian morphology, and release of adrenal steroid hormones, metabolic syndrome, and hereditary factors. The review explored the role of dysbiosis and the mechanisms through which microbial dysbiosis can affect PCOS development. In recent time, various research groups highlighted the role of microbial gut dysbiosis associated with obesity as potential etiological factor for the PCOS. In the present review, we reviewed the mechanisms attributed to the microbial dysbiosis and treatment approaches to deal with the situation.

High methionine intake alters gut microbiota and lipid profile and leads to liver steatosis in mice

Methionine is an important sulfur-containing amino acid. Health effects of both methionine restriction (MR) and methionine supplementation (MS) have been studied. This study aimed to investigate the impact of a high-methionine diet (HMD) (1.64% methionine) on both the gut and liver functions in mice through multi-omic analyses. Hepatic steatosis and compromised gut barrier function were observed in mice fed the HMD. RNA-sequencing (RNA-seq) analysis of liver gene expression patterns revealed the upregulation of lipid synthesis and degradation pathways, cholesterol metabolism and inflammation-related nucleotide-binding oligomerization domain (NOD)-like receptor signaling pathway. Metagenomic sequencing of cecal content demonstrated a shift in gut microbial composition with an increased abundance of opportunistic pathogens and gut microbial functions with up-regulated lipopolysaccharide (LPS) biosynthesis in mice fed HMD. Metabolomic study of cecal content showed an altered gut lipid profile and the level of bioactive lipids, including docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), palmitoylethanolamide (PEA), linoleoyl ethanolamide (LEA) and arachidonoyl ethanolamide (AEA), that carry anti-inflammatory effects significantly reduced in the gut of mice fed the HMD. Correlation analysis demonstrated that gut microbiota was highly associated with liver and gut functions and gut bioactive lipid content. In conclusion, this study suggested that the HMD exerted negative impacts on both the gut and liver, and an adequate amount of methionine intake should be carefully determined to ensure normal physiological function without causing adverse effects.

Acupuncture influences multiple diseases by regulating gut microbiota

Acupuncture, an important green and side effect-free therapy in traditional Chinese medicine, is widely use both domestically and internationally. Acupuncture can interact with the gut microbiota and influence various diseases, including metabolic diseases, gastrointestinal diseases, mental disorders, nervous system diseases, and other diseases. This review presents a thorough analysis of these interactions and their impacts and examines the alterations in the gut microbiota and the potential clinical outcomes following acupuncture intervention to establish a basis for the future utilization of acupuncture in clinical treatments.

Hericium erinaceus polysaccharides ameliorate nonalcoholic fatty liver disease via gut microbiota and tryptophan metabolism regulation in an aged laying hen model

Polysaccharides extracted from Hericium erinaceus (HEP) exhibit hepatoprotective activity in the alleviation of non-alcoholic fatty liver disease (NAFLD); however, the mechanisms underlying whether and how HEP regulation of the gut microbiota to alleviate liver-associated metabolic disorders are not well understood. This study used an aged laying hen model to explore the mechanisms through which HEP alleviates NAFLD, with a focus on regulatory function of HEP in the gut microbiome. The results showed that HEP ameliorated hepatic damage and metabolic disorders by improving intestinal barrier function and shaping the gut microbiota and tryptophan metabolic profiles. HEP increased the abundance of Lactobacillus and certain tryptophan metabolites, including indole-3-carboxylic acid, kynurenic acid, and tryptamine in the cecum. These metabolites upregulated the expression of ZO-1 and Occludin by activating the AhR and restoring the intestinal barrier integrity. The increased intestinal barrier functions decreased LPS transferring from the intestine to the liver, inhibited hepatic LPS/TLR4/MyD88/NF-κB pathway activation, and reduced hepatic inflammatory response and apoptosis. Fecal microbiota transplantation experiments further confirmed that the hepatoprotective effect is likely mediated by HEP-altered gut microbiota and their metabolites. Overall, dietary HEP could ameliorate the hepatic damage and metabolic disorders of NAFLD through regulating the "gut-liver" axis.

Effect of lipopolysaccharides from pathogenic bacteria on broiler chickens' productivity: a meta-analysis

1. This meta-analysis investigated the impact of LPS and covariates (serotype, rearing period and administration route) on the productivity parameters of broiler chickens (average daily feed intake (ADFI), average daily gain (ADG) and feed conversion ratio (FCR)).2. Thirty-two eligible studies were included. Hedges' g effect size was determined using a random-effects model at 95% confidence interval.3. Results showed that LPS significantly decreased average daily feed intake (ADFI; p < 0.0001) and average daily gain (ADG; p < 0.0001) and increased FCR (p < 0.0001). The serotypes Escherichia coli 055: B5 (EC055: B5) and Escherichia coli 0127: B8 (EC 0127: B8) significantly reduced ADFI and ADG, and the serotype EC 055: B5 significantly increased the FCR (p < 0.05).4. The intraperitoneal administration of the LPS significantly reduced the productivity of broiler chickens (p < 0.05), but other administration routes did not show such effects. The reduction in ADFI and ADG was found in all rearing periods (p < 0.05), and the increase in FCR was observed in the starter (p = 0.0302) and grower periods (p = 0.0031).5. Exposure to LPS significantly reduced the productivity of broiler chickens (p < 0.05). However, no relationship was observed between LPS dosage and productivity as indicated by the meta-regression study.6. The findings indicated that LPS has detrimental effects on broiler chickens' ADFI, ADG and FCR across various LPS serotypes and rearing periods. These detrimental impacts of LPS remain consistent regardless of the administered dosage.

Human milk affects TLR4 activation and LPS-induced inflammatory cytokine expression in Caco-2 intestinal epithelial cells

Human milk (HM) components affect immune cell toll-like receptor 4 (TLR4) signaling. However, studies examining the immunomodulatory impacts of HM on TLR4 signaling in intestinal epithelial cells (IECs) are limited. This study utilized both a TLR4 reporter cell line and a Caco-2 IEC model to examine the effects of HM on lipopolysaccharide (LPS)-induced TLR4 activation and cytokine responses, respectively. Additionally, we performed fast protein liquid chromatography and mass spectrometry to identify a HM component that contributes to the effect of HM on LPS/TLR4 signaling. HM enhances LPS-induced TLR4 signaling as well as LPS-induced IEC gene expression of pro-inflammatory cytokines and negative regulators of NF-κB. Human serum albumin (HSA) present in HM contributes to these effects. HSA within HM synergizes with LPS to induce IEC gene expression of pro-inflammatory cytokines and negative regulators of NF-κB. Altogether, this study provides mechanistic evidence behind the immunomodulatory function of HM on IECs, which may contribute to an enhanced immune response in breast-fed neonates.

Gut Microbiome and Polycystic Ovary Syndrome: Interplay of Associated Microbial-Metabolite Pathways and Therapeutic Strategies

Polycystic ovary syndrome (PCOS) is a multifaceted disease with an intricate etiology affecting reproductive-aged women. Despite attempts to unravel the pathophysiology, the molecular mechanism of PCOS remains unknown. There are no effective or suitable therapeutic strategies available to ameliorate PCOS; however, the symptoms can be managed. In recent years, a strong association has been found between the gut microbiome and PCOS, leading to the formulation of novel ideas on the genesis and pathological processes of PCOS. Further, gut microbiome dysbiosis involving microbial metabolites may trigger PCOS symptoms via many mechanistic pathways including those associated with carbohydrates, short-chain fatty acids, lipopolysaccharides, bile acids, and gut-brain axis. We present the mechanistic pathways of PCOS-related microbial metabolites and therapeutic opportunities available to treat PCOS, such as prebiotics, probiotics, and fecal microbiota therapy. In addition, the current review highlights the emerging treatment strategies available to alleviate the symptoms of PCOS.

Exploring the Role of Gut-Lung Interactions in COPD Pathogenesis: A Comprehensive Review on Microbiota Characteristics and Inflammation Modulation

Chronic obstructive pulmonary disease (COPD) is a paramount contributor to global morbidity and mortality. Over the past decade, the concept of the "gut-lung axis" has emerged, offering a lens through which to examine the intricate interplay between the host, microbiome, and respiratory diseases, including COPD. An expanding body of evidence underscores that the composition of both the gastrointestinal and respiratory microbiome deviates in COPD patients compared to healthy individuals, leading to distinct host immune responses and clinical manifestations. The objective of this review is to provide a concise overview of the role both gut and respiratory microbiome play in the development of COPD. This was accomplished by compiling current literature on the microbiome profile in stable and exacerbated cases of COPD, as well as exploring the biological mechanisms through a discussion of relevant experiments conducted on murine models. Hallmark characteristics of the microbial profile in COPD encompass reduced Prevotella species in the respiratory microbiome, culminating in a loss of anti-inflammatory protection, and diminished Bacteroidetes in the gut microbiome, leading to a decrease in protective short-chain fatty acids. The proliferation of Proteobacteria, particularly the Haemophilus species, Moraxellaspecies, and Pseudomonas species contribute to COPD pathologies via recognition of proinflammatory lipopolysaccharide via Toll-like receptors. As a consequence, deteriorated pulmonary function, enhanced severity, increased onset of exacerbations, and elevated mortality were observed.

Probiotics, gut microbiome, and cardiovascular diseases: An update

Cardiovascular diseases (CVD) are one of the most challenging diseases and many factors have been demonstrated to affect their pathogenesis. One of the major factors that affect CVDs, especially atherosclerosis, is the gut microbiota (GM). Genetics play a key role in linking CVDs with GM, in addition to some environmental factors which can be either beneficial or harmful. The interplay between GM and CVDs is complex due to the numerous mechanisms through which microbial components and their metabolites can influence CVDs. Within this interplay, the immune system plays a major role, mainly based on the immunomodulatory effects of microbial dysbiosis and its resulting metabolites. The resulting modulation of chronic inflammatory processes was found to reduce the severity of CVDs and to maintain cardiovascular health. To better understand the specific roles of GM-related metabolites in this interplay, this review presents an updated perspective on gut metabolites related effects on the cardiovascular system, highlighting the possible benefits of probiotics in therapeutic strategies.

Effects of inhaled fine particulate matter on the lung injury as well as gut microbiota in broilers

Fine particulate matter (PM2.5) has been widely regarded as an important environmental risk factor that has widely influenced health of both animals and humans. Lung injury is the main cause of PM2.5 affecting respiratory tract health. Gut microbiota participates in the development of lung injury in many pathological processes. However, there is still unknown the specific effects of PM2.5 on the gut-lung axis in broilers. Thus, we conducted a broiler model based on 3-wk-old male Arbor Acres broiler to explore the underlying mechanism. Our results showed that PM2.5 exposure triggered TLR4 signaling pathway and induced the increase of IL-6, IFN-γ, TNF-α expression as well as the decrease of IL-10 expression in the lung. Inhaled PM2.5 exposure significantly altered the gut microbiota diversity and community. Specifically, PM2.5 exposure decreased α diversity and altered β diversity of gut microbiota, and reduced the abundance of DTU089, Oscillospirales, Staphylococcus, and increased the Escherichia-Shigella abundance, leading to the increase of gut-derived lipopolysaccharides (LPS). Moreover, PM2.5 significantly disrupted the intestinal epithelial barrier by reducing the expression of muc2 and claudin-1 to increase intestinal permeability, which possibly facilitated the LPS translocation into the blood. Spearman analysis revealed that gut microbiota dysbiosis was positively related to TLR4, TNF-α, and IFN-γ expression in the lung. In summary, our results showed that PM2.5 exposure induced lung injury by causing inflammation and triggering TLR4 signaling pathway, and also induced gut microbiota dysbiosis resulting in the overproduction of gut-derived LPS. And gut microbiota dysbiosis may be associated with lung injury. The above results provide basis data to comprehend the potential role of gut microbiota dysbiosis in the lung injury as well as providing a new regulatory target for alleviating lung injury associated with environmental pollutants.

Lactiplantibacillus plantarum ZDY2013 Inhibits the Development of Non-Alcoholic Fatty Liver Disease by Regulating the Intestinal Microbiota and Modulating the PI3K/Akt Pathway

Non-alcoholic fatty liver disease (NAFLD) is a common chronic hepatic condition whose impact on human health is increasingly significant. The imbalance of the gut microbiome, linked to insulin resistance, heightened intestinal permeability, and pro-inflammatory reactions, may be the linchpin in the development of NAFLD. In our research, the impact of Lactiplantibacillus plantarum ZDY2013 administration for 12 weeks on gut microbiota dysbiosis induced by a high-fat, high-fructose, high-cholesterol (FHHC) diet in male C57BL/6n mice was investigated. Research results presented that the intervention of L. plantarum ZDY2013 in mice fed with the FHHC diet could restore their liver function and regulate oxidative stress. Compared to mice in the model group, the intervention of L. plantarum ZDY2013 significantly regulated the gut microbiota, inhibited the LPS/NF-κB pathway, and led to a lower level of colonic inflammation in the mice administered with L. plantarum ZDY2013. It also improved insulin resistance to regulate the PI3K/Akt pathway and lipid metabolism, thereby resulting in reduced fat accumulation in the liver. The above results suggest that the intervention of L. plantarum ZDY2013 can hinder the progression of diet-induced NAFLD by reducing inflammation to regulate the PI3K/Akt pathway and regulating gut microbiota disturbance.

Advances in molecular agents targeting toll-like receptor 4 signaling pathways for potential treatment of sepsis

Sepsis is a systemic inflammatory response syndrome caused by an infection. Toll-like receptor 4 (TLR4) is activated by endogenous molecules released by injured or necrotic tissues. Additionally, TLR4 is remarkably sensitive to infection of various bacteria and can rapidly stimulate host defense responses. The TLR4 signaling pathway plays an important role in sepsis by activating the inflammatory response. Accordingly, as part of efforts to improve the inflammatory response and survival rate of patients with sepsis, several drugs have been developed to regulate the inflammatory signaling pathways mediated by TLR4. Inhibition of TLR4 signal transduction can be directed toward either TLR4 directly or other proteins in the TLR4 signaling pathway. Here, we review the advances in the development of small-molecule agents and peptides targeting regulation of the TLR4 signaling pathway, which are characterized according to their structural characteristics as polyphenols, terpenoids, steroids, antibiotics, anthraquinones, inorganic compounds, and others. Therefore, regulating the expression of the TLR4 signaling pathway and modulating its effects has broad prospects as a target for the treatment of lung, liver, kidneys, and other important organs injury in sepsis.

Gut microbiota and its metabolites in Alzheimer's disease: from pathogenesis to treatment

Introduction

An increasing number of studies have demonstrated that altered microbial diversity and function (such as metabolites), or ecological disorders, regulate bowel-brain axis involvement in the pathophysiologic processes in Alzheimer's disease (AD). The dysregulation of microbes and their metabolites can be a double-edged sword in AD, presenting the possibility of microbiome-based treatment options. This review describes the link between ecological imbalances and AD, the interactions between AD treatment modalities and the microbiota, and the potential of interventions such as prebiotics, probiotics, synbiotics, fecal microbiota transplantation, and dietary interventions as complementary therapeutic strategies targeting AD pathogenesis and progression.

Survey methodology

Articles from PubMed and china.com on intestinal flora and AD were summarized to analyze the data and conclusions carefully to ensure the comprehensiveness, completeness, and accuracy of this review.

Conclusions

Regulating the gut flora ecological balance upregulates neurotrophic factor expression, regulates the microbiota-gut-brain (MGB) axis, and suppresses the inflammatory responses. Based on emerging research, this review explored novel directions for future AD research and clinical interventions, injecting new vitality into microbiota research development.

Oxidized/unmodified-polyethylene microplastics neurotoxicity in mice: Perspective from microbiota-gut-brain axis

Microplastics (MPs) are inevitably oxidized in the environment, and their potential toxicity to organisms has attracted wide attention. However, the neurotoxicity and mechanism of oxidized polyethylene (Ox-PE) MPs to organisms remain unclear. Herein, we prepared oxidized low-density polyethylene (Ox-LDPE) and established a model of MPs exposure by continuously orally gavage of C57BL/6 J mice with LDPE-MPs/Ox-LDPE-MPs for 28 days with or without oral administration of Lactobacillus plantarum DP189 and galactooligosaccharides (DP189&GOS). The experimental results indicated that LDPE-MPs or Ox-LDPE-MPs caused several adverse effects in mice, mainly manifested by behavioral changes, disruption of the intestinal and blood-brain barrier (BBB), and simultaneous oxidative stress, inflammatory reactions, and pathological damage in the brain and intestines. Brain transcriptomic analysis revealed that the cholinergic synaptic signaling pathways, which affect cognitive function, were significantly disrupted after exposure to LDPE-MPs or Ox-LDPE-MPs. Real-time quantitative polymerase chain reaction and Western Blotting results further demonstrated that the critical genes (Slc5a7, Chat and Slc18a3) and proteins (Chat and Slc18a3) in the cholinergic synaptic signaling pathway were significantly down-regulated after exposure to LDPE-MPs or Ox-LDPE-MPs. These alterations lead to reduced acetylcholine concentration, which causes cognitive dysfunction in mice. Importantly, the DP189&GOS interventions effectively mitigated the MPs-induced cognitive dysfunction and intestinal microbiota alteration, improved intestinal and BBB integrity, attenuated the oxidative stress and inflammatory response, and also saw a rebound in the release of acetylcholine. These results indicated that LDPE-MPs and Ox-LDPE-MPs exert neurotoxic effects on mice by inducing oxidative stress, inflammatory responses, and dysregulation of cholinergic signaling pathways in the mouse brain. That probiotic supplementation is effective in attenuating MPs-induced neurotoxicity in mice. Overall, this study reveals the potential mechanisms of neurotoxicity of LDPE-MPs and Ox-LDPE-MPs on mice and their improvement measures, necessary to assess the potential risks of plastic contaminants to human health.

Anti-Diabetic Potentials of Lactobacillus Strains by Modulating Gut Microbiota Structure and β-Cells Regeneration in the Pancreatic Islets of Alloxan-Induced Diabetic Rats

Diabetes mellitus, a most common endocrine disorder of glucose metabolism, has become a global epidemic and poses a serious public health threat with an increased socio-economic burden. Escalating incidence of diabetes is correlated with changes in lifestyle and food habits that cause gut microbiome dysbiosis and β-cells damage, which can be addressed with dietary interventions containing probiotics. Hence, the search for probiotics of human origin with anti-diabetic, anti-AGE, and anti-ACE potentials has gained renewed interest for the effective management of diabetes and its associated complications. The present study used an alloxan (AXN)-induced diabetic rat model to investigate the effects of potential probiotic Lacticaseibacillus casei MKU1, Lactiplantibacillus pentosus MKU3, and Lactiplantibacillus plantarum MKU7 administration individually on physiochemical parameters related to diabetic pathogenesis. Experimental animals were randomly allotted into six groups viz. NCG (control), DCG (AXN), DGM (metformin), DGP1 (MKU1), DGP2 (MKU3), and DGP3 (MKU7), and biochemical data like serum glucose, insulin, AngII, ACE, HbA1c, and TNF-α levels were measured until 90 days. Our results suggest that oral administration with MKU1, MKU3, or MKU7 significantly improved serum insulin levels, glycemic control, glucose tolerance, and body weight. Additionally, β-cell mass was increased by preserving islet integrity in Lactobacillus-treated diabetic rats, whereas TNF-α (~40%), AngII (~30%), and ACE levels (~50%) were strongly inhibited and enhanced sIgA production (5.8 folds) abundantly. Furthermore, Lactobacillus administration positively influenced the gut microbiome with a significant increase in the abundance of Lactobacillus species and the beneficial Bacteroides uniformis and Bacteroides fragilis, while decreased the pathogenic Proteus vulgaris and Parabacteroides distasonis. Among the probiotic treatment groups, L. pentosus MKU3 performed greatly in almost all parameters, indicating its potential use for alleviating diabetes-associated complications.

Treadmill exercise can regulate the redox balance in the livers of APP/PS1 mice and reduce LPS accumulation in their brains through the gut-liver-kupffer cell axis

A growing body of clinical data has shown that patients with Alzheimer's disease (AD) have symptoms such as liver dysfunction and microbial-gut-brain axis dysfunction in addition to brain pathology, presenting a systemic multisystemic pathogenesis. Considering the systemic benefits of exercise, here, we first observed the effects of long-term treadmill exercise on liver injuries in APP/PS1 transgenic AD mice and explored the potential mechanisms of the gut-liver-brain axis's role in mediating exercise's ability to reduce bacterial lipopolysaccharide (LPS) pathology in the brain. The results showed that the livers of the AD mice were in states of oxidative stress, while the mice after long-term treadmill exercise showed alleviation of their oxidative stress, their intestinal barriers were protected, and the ability of their Kupffer cells to hydrolyze LPS was improved, in addition to the accumulation of LPS in their brains being reduced. Notably, the livers of the AD mice were in immunosuppressed states, with lower pro-oxidative and antioxidative levels than the livers of the wild-type mice, while exercise increased both their oxidative and antioxidative levels. These results suggest that long-term exercise modulates hepatic redox homeostasis in AD mice, attenuates oxidative damage, and reduces the accumulation of LPS in the brain through the combined action of the intestine-liver-Kupffer cells.

S-amlodipine induces liver inflammation and dysfunction through the alteration of intestinal microbiome in a rat model

S-amlodipine, a commonly prescribed antihypertensive agent, is widely used in clinical settings to treat hypertension. However, the potential adverse effects of long-term S-amlodipine treatment on the liver remain uncertain, given the cautionary recommendations from clinicians regarding its administration in individuals with impaired liver function. To address this, we conducted a study using an eight-week-old male rat model and administered a daily dose of 0.6 ~ 5 mg/kg of S-amlodipine for 7 weeks. Our findings demonstrated that 1.2 ~ 5 mg/kg of S-amlodipine treatment induced liver inflammation and associated dysfunction in rats, further in vitro experiments revealed that the observed liver inflammation and dysfunction were not attributable to direct effects of S-amlodipine on the liver. Metagenome sequencing analysis revealed that S-amlodipine treatment led to alterations in the gut microbiome of rats, with the bloom of E. coli (4.5 ~ 6.6-fold increase) and a decrease in A. muciniphila (1,613.4 ~ 2,000-fold decrease) and B. uniformis (20.6 ~ 202.7-fold decrease), subsequently causing an increase in the gut bacterial lipopolysaccharide (LPS) content (1.4 ~ 1.5-fold increase in feces). S-amlodipine treatment also induced damage to the intestinal barrier and increased intestinal permeability, as confirmed by elevated levels of fecal albumin; furthermore, the flux of gut bacterial LPS into the bloodstream through the portal vein resulted in an increase in serum LPS content (3.3 ~ 4-fold increase). LPS induces liver inflammation and subsequent dysfunction in rats by activating the TLR4 pathway. This study is the first to show that S-amlodipine induces liver inflammation and dysfunction by perturbing the rat gut microbiome. These results indicate the adverse effects of S-amlodipine on the liver and provide a rich understanding of the safety of long-term S-amlodipine administration.

Exploring the host range for genetic transfer of magnetic organelle biosynthesis

Magnetosomes produced by magnetotactic bacteria have great potential for application in biotechnology and medicine due to their unique physicochemical properties and high biocompatibility. Attempts to transfer the genes for magnetosome biosynthesis into non-magnetic organisms have had mixed results. Here we report on a systematic study to identify key components needed for magnetosome biosynthesis after gene transfer. We transfer magnetosome genes to 25 proteobacterial hosts, generating seven new magnetosome-producing strains. We characterize the recombinant magnetosomes produced by these strains and demonstrate that denitrification and anaerobic photosynthesis are linked to the ability to synthesize magnetosomes upon the gene transfer. In addition, we show that the number of magnetosomes synthesized by a foreign host negatively correlates with the guanine-cytosine content difference between the host and the gene donor. Our findings have profound implications for the generation of magnetized living cells and the potential for transgenic biogenic magnetic nanoparticle production.

The role of the glycome in symbiotic host-microbe interactions

Glycosylation plays a crucial role in many aspects of cell biology, including cellular and organismal integrity, structure-and-function of many glycosylated molecules in the cell, signal transduction, development, cancer, and in a number of diseases. Besides, at the inter-organismal level of interaction, a variety of glycosylated molecules are involved in the host-microbiota recognition and initiation of downstream signalling cascades depending on the outcomes of the glycome-mediated ascertainment. The role of glycosylation in host-microbe interactions is better elaborated within the context of virulence and pathogenicity in bacterial infection processes but the symbiotic host-microbe relationships also involve substantive glycome-mediated interactions. The works in the latter field have been reviewed to a much lesser extent, and the main aim of this mini-review is to compensate for this deficiency and summarise the role of glycomics in host-microbe symbiotic interactions.

Lactobacillus reuteri Ameliorates Lipopolysaccharide-Induced Acute Lung Injury by Modulating the Gut Microbiota in Mice

Acute lung injury (ALI) causes lung inflammation and edema as well as resulting in gut microbiota disorder. Probiotics, however, can improve the gut microbiota composition and modulate its immune response, playing an important role in ALI pathogenesis. Therefore, our study aims to investigate the effect of Lactobacillus reuteri on Lipopolysaccharide (LPS)-induced ALI in mice and to probe the mechanism of its synergistic modulatory effect on the lungs and intestines. We assessed the therapeutic effects of L. reuteri in the ALI mouse model by histopathology, alveolar lavage fluid and serum inflammatory factor analysis and explored microbiome and transcriptome alterations. L. reuteri intervention effectively attenuated lung tissue injury and significantly reduced the LPS-induced inflammatory response and macrophage and neutrophil infiltration. Additionally, L. reuteri improved the intestinal barrier function and remodeled the disordered microbiota. In conclusion, our study showed that L. reuteri attenuated the inflammatory response, ameliorated the pulmonary edema, repaired the intestinal barrier, and remodeled the gut microbiota in ALI mice. This study provides new perspectives on the clinical treatment of ALI.

Lipopolysaccharide (LPS) extracted from Bacteroides vulgatus effectively prevents LPS extracted from Escherichia coli from inducing epithelial‑mesenchymal transition

Pathological epithelial‑mesenchymal transition (EMT) has been shown to fulfill a key role in the development and progression of a variety of lung diseases. It has been demonstrated that the inflammatory microenvironment is a decisive factor in inducing pathological EMT. Hexacylated lipopolysaccharide (LPS) [or proacylated lipopolysaccharide (P‑LPS), which functions as proinflammatory lipopolysaccharide] is one of the most effective Toll‑like receptor 4 (TLR4) agonists. Furthermore, the pentacylated and tetracylated form of lipopolysaccharide (or A‑LPS, which functions as anti‑inflammatory lipopolysaccharide) has been shown to elicit competitive antagonistic effects against the pro‑inflammatory activity of P‑LPS. At present, it remains unclear whether LPS extracted from Bacteroides vulgatus (BV‑LPS) can prevent LPS extracted from Escherichia coli (EC‑LPS) from inducing pathological EMT. In the present study, A549 cells and C57BL/6 mice lung tissue were both induced by EC‑LPS (P‑LPS) and BV‑LPS (A‑LPS), either alone or in combination. The anticipated anti‑inflammatory effects of BV‑LPS were analyzed by examining the lung coefficient, lung pathology, A549 cell morphology and expression levels both of the inflammatory cytokines, IL‑1β, IL‑6 and TNF‑α and of the EMT signature proteins, epithelial cadherin (E‑cadherin), α‑smooth muscle actin (α‑SMA) and vimentin. In addition, the expression levels of TLR4, bone morphogenic protein and activin membrane‑bound inhibitor (BAMBI) and Snail were detected and the possible mechanism underlying how BV‑LPS may prevent EC‑LPS‑induced EMT was analyzed. The results obtained showed that the morphology of the A549 cells was significantly polarized, the lung index was significantly increased, the alveolar structure was collapsed and the expression levels of IL‑1β, IL‑6, TNF‑α, α‑SMA, vimentin, TLR4 and Snail in both lung tissue and A549 cells were significantly increased, whereas those of E‑cadherin and BAMBI were significantly decreased. Treatment with BV‑LPS in combination with EC‑LPS was found to reverse these changes. In conclusion, the present study demonstrated that BV‑LPS is able to effectively prevent EC‑LPS‑induced EMT in A549 cells and in mouse lung tissue and furthermore, the underlying mechanism may be associated with inhibition of the TLR4/BAMBI/Snail signaling pathway.

Antibiotic-induced gut dysbiosis and cognitive, emotional, and behavioral changes in rodents: a systematic review and meta-analysis

There are previous epidemiological studies reporting associations between antibiotic use and psychiatric symptoms. Antibiotic-induced gut dysbiosis and alteration of microbiota-gut-brain axis communication has been proposed to play a role in this association. In this systematic review and meta-analysis, we reviewed published articles that have presented results on changes in cognition, emotion, and behavior in rodents (rats and mice) after antibiotic-induced gut dysbiosis. We searched three databases-PubMed, Web of Science, and SCOPUS to identify such articles using dedicated search strings and extracted data from 48 articles. Increase in anxiety and depression-like behavior was reported in 32.7 and 40.7 percent of the study-populations, respectively. Decrease in sociability, social novelty preference, recognition memory and spatial cognition was found in 18.1, 35.3, 26.1, and 62.5 percent of the study-populations, respectively. Only one bacterial taxon (increase in gut Proteobacteria) showed statistically significant association with behavioral changes (increase in anxiety). There were no consistent findings with statistical significance for the potential biomarkers [Brain-derived neurotrophic factor (BDNF) expression in the hippocampus, serum corticosterone and circulating IL-6 and IL-1β levels]. Results of the meta-analysis revealed a significant association between symptoms of negative valence system (including anxiety and depression) and cognitive system (decreased spatial cognition) with antibiotic intake (p < 0.05). However, between-study heterogeneity and publication bias were statistically significant (p < 0.05). Risk of bias was evaluated to be high in the majority of the studies. We identified and discussed several reasons that could contribute to the heterogeneity between the results of the studies examined. The results of the meta-analysis provide promising evidence that there is indeed an association between antibiotic-induced gut dysbiosis and psychopathologies. However, inconsistencies in the implemented methodologies make generalizing these results difficult. Gut microbiota depletion using antibiotics may be a useful strategy to evaluate if and how gut microbes influence cognition, emotion, and behavior, but the heterogeneity in methodologies used precludes any definitive interpretations for a translational impact on clinical practice.

Dietary High Glycinin Reduces Growth Performance and Impairs Liver and Intestinal Health Status of Orange-Spotted Grouper (Epinephelus coioides)

The aim of the study was to investigate whether the negative effects of dietary glycinin are linked to the structural integrity damage, apoptosis promotion and microbiota alteration in the intestine of orange-spotted grouper (Epinephelus coioides). The basal diet (FM diet) was formulated to contain 48% protein and 11% lipid. Fish meal was replaced by soybean meal (SBM) in FM diets to prepare the SBM diet. Two experimental diets were prepared, containing 4.5% and 10% glycinin in the FM diets (G-4.5 and G-10, respectively). Triplicate groups of 20 fish in each tank (initial weight: 8.01 ± 0.10 g) were fed the four diets across an 8 week growth trial period. Fish fed SBM diets had reduced growth rate, hepatosomatic index, liver total antioxidant capacity and GSH-Px activity, but elevated liver MDA content vs. FM diets. The G-4.5 exhibited maximum growth and the G-10 exhibited a comparable growth with that of the FM diet group. The SBM and G-10 diets down-regulated intestinal tight junction function genes (occludin, claudin-3 and ZO-1) and intestinal apoptosis genes (caspase-3, caspase-8, caspase-9, bcl-2 and bcl-xL), but elevated blood diamine oxidase activity, D-lactic acid and endotoxin contents related to intestinal mucosal permeability, as well as the number of intestinal apoptosis vs FM diets. The intestinal abundance of phylum Proteobacteria and genus Vibrio in SBM diets were higher than those in groups receiving other diets. As for the expression of intestinal inflammatory factor genes, in SBM and G-10 diets vs. FM diets, pro-inflammatory genes (TNF-α, IL-1β and IL-8) were up-regulated, but anti-inflammatory genes (TGF-β1 and IL-10) were down-regulated. The results indicate that dietary 10% glycinin rather than 4.5% glycinin could decrease hepatic antioxidant ability and destroy both the intestinal microbiota profile and morphological integrity through disrupting the tight junction structure of the intestine, increasing intestinal mucosal permeability and apoptosis. These results further trigger intestinal inflammatory reactions and even enteritis, ultimately leading to the poor growth of fish.

Dapagliflozin Mitigates Hypotension in Lipopolysaccharide-Induced Acute Inflammation Independent of Glycemia Level

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been suggested to have anti-inflammatory properties in diabetes. The goal of this study was to evaluate the role of the SGLT2 inhibitor dapagliflozin (DAPA) in the attenuation of lipopolysaccharide (LPS)-induced hypotension. Male Wistar albino rats were divided into normal and diabetic groups and received DAPA (1 mg/kg/day) for two weeks followed by a single dose of 10 mg/kg LPS. Blood pressure was recorded throughout the study and the circulatory levels of cytokines were assessed using a multiplex array, while the aortas were harvested for analysis. DAPA attenuated the vasodilation and hypotension caused by LPS. Mean arterial pressure (MAP) was preserved in the normal and diabetic DAPA-treated septic groups (MAP = 83.17 ± 5.27, 98.43 ± 5.57 mmHg) compared to the vehicle-treated septic groups (MAP = 65.60 ± 3.31, 68.21 ± 5.88 mmHg). Most of the cytokines induced by LPS were decreased in the DAPA-treated septic groups. In the aorta, the inducible nitric oxide synthase-derived nitric oxide had lower expression in the DAPA-treated rats. In contrast, the expression of α-smooth muscle actin, a marker of the vessel's contractile state, was higher in the DAPA-treated rats in comparison with non-treated septic rats. These findings revealed that the protective role of DAPA against LPS-induced hypotension is likely to be glucose-lowering independent, as was observed in the non-diabetic septic group. Taken together, the results show that DAPA has a potential effect in the prevention of the hemodynamic disturbances of sepsis regardless of glycemia levels.

Metformin Contributes to the Therapeutic Effects of Acne Vulgaris by Modifying the Gut Microbiome

Background. Considering the increasing side effects of the first-line treatment for acne vulgaris, metformin was developed to be an effective adjunct therapy, but its mechanism of action is poorly defined. Recent evidence shows that the gut microbiota is a site of metformin action. The aim of this study was to evaluate the effects and mechanism of action for metformin in the adjuvant treatment of acne vulgaris by regulating gut microbiota. Methods. First, untreated acne patients were randomly allocated into two treatment groups. Both groups were treated with isotretinoin, but only one was additionally treated with metformin, for three months. Sprague Dawley (SD) rats were used as acne models, and they were also separated into groups that received isotretinoin, metformin, a combination of isotretinoin and metformin, and the vehicle, respectively. Then, the fecal samples from drug-intervention rats were transferred to germ-free rats with acne. The severity of the disease was evaluated using the Global Acne Grading System (GAGS) scoring for patients, and the number of comedones and mononuclear cells in pathological sections was used for rats. The composition of the gut microbiota was detected using gene sequencing for 16S rDNA. Results. Metformin had strong effects on the composition and function of the gut microbiota, and this correlated with the reduction in the severity of acne in both humans and rats. The fecal transfer to pseudo-germ-free rats improved both the inflammatory phenotype and comedones of acne in recipients of metformin-altered microbiota. Conclusion. The results suggest that metformin improves the symptoms of acne vulgaris by modulating the gut microbiota.

Dimethyl itaconate ameliorates cognitive impairment induced by a high-fat diet via the gut-brain axis in mice

BACKGROUND

Gut homeostasis, including intestinal immunity and microbiome, is essential for cognitive function via the gut-brain axis. This axis is altered in high-fat diet (HFD)-induced cognitive impairment and is closely associated with neurodegenerative diseases. Dimethyl itaconate (DI) is an itaconate derivative and has recently attracted extensive interest due to its anti-inflammatory effect. This study investigated whether intraperitoneal administration of DI improves the gut-brain axis and prevents cognitive deficits in HF diet-fed mice.

RESULTS

DI effectively attenuated HFD-induced cognitive decline in behavioral tests of object location, novel object recognition, and nesting building, concurrent with the improvement of hippocampal RNA transcription profiles of genes associated with cognition and synaptic plasticity. In agreement, DI reduced the damage of synaptic ultrastructure and deficit of proteins (BDNF, SYN, and PSD95), the microglial activation, and neuroinflammation in the HFD-fed mice. In the colon, DI significantly lowered macrophage infiltration and the expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) in mice on the HF diet, while upregulating the expression of immune homeostasis-related cytokines (IL-22, IL-23) and antimicrobial peptide Reg3γ. Moreover, DI alleviated HFD-induced gut barrier impairments, including elevation of colonic mucus thickness and expression of tight junction proteins (zonula occludens-1, occludin). Notably, HFD-induced microbiome alteration was improved by DI supplementation, characterized by the increase of propionate- and butyrate-producing bacteria. Correspondingly, DI increased the levels of propionate and butyrate in the serum of HFD mice. Intriguingly, fecal microbiome transplantation from DI-treated HF mice facilitated cognitive variables compared with HF mice, including higher cognitive indexes in behavior tests and optimization of hippocampal synaptic ultrastructure. These results highlight the gut microbiota is necessary for the effects of DI in improving cognitive impairment.

CONCLUSIONS

The present study provides the first evidence that DI improves cognition and brain function with significant beneficial effects via the gut-brain axis, suggesting that DI may serve as a novel drug for treating obesity-associated neurodegenerative diseases. Video Abstract.

In Vitro Anti-Inflammatory and Antioxidant Activities of pH-Responsive Resveratrol-Urocanic Acid Nano-Assemblies

Inflammatory environments provide vital biochemical stimuli (i.e., oxidative stress, pH, and enzymes) for triggered drug delivery in a controlled manner. Inflammation alters the local pH within the affected tissues. As a result, pH-sensitive nanomaterials can be used to effectively target drugs to the site of inflammation. Herein, we designed pH-sensitive nanoparticles in which resveratrol (an anti-inflammatory and antioxidant compound (RES)) and urocanic acid (UA) were complexed with a pH-sensitive moiety using an emulsion method. These RES-UA NPs were characterized by transmission electron microscopy, dynamic light scattering, zeta potential, and FT-IR spectroscopy. The anti-inflammatory and antioxidant activities of the RES-UA NPs were assessed in RAW 264.7 macrophages. The NPs were circular in shape and ranged in size from 106 to 180 nm. The RES-UA NPs suppressed the mRNA expression of the pro-inflammatory molecules inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in a concentration-dependent manner. Incubation of LPS-stimulated macrophages with RES-UA NPs reduced the generation of reactive oxygen species (ROS) in a concentration-dependent manner. These results suggest that pH-responsive RES-UA NPs can be used to decrease ROS generation and inflammation.

Neuroprotective Effects of Sodium Butyrate by Restoring Gut Microbiota and Inhibiting TLR4 Signaling in Mice with MPTP-Induced Parkinson's Disease

Parkinson's disease (PD) is a prevalent type of neurodegenerative disease. There is mounting evidence that the gut microbiota is involved in the pathogenesis of PD. Sodium butyrate (NaB) can regulate gut microbiota and improve brain functioning in neurological disorders. Hence, we examined whether the neuroprotective function of NaB on PD was mediated by the modulation of gut microbial dysbiosis and revealed its possible mechanisms. Mice were administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 7 consecutive days to construct the PD model. NaB gavage was given 2 h after the daily MPTP injections for 21 days. NaB improved the motor functioning of PD mice, increased striatal neurotransmitter levels, and reduced the death of dopaminergic neurons. The 16S rRNA sequencing analysis revealed that NaB restored the gut microbial dysbiosis. NaB also attenuated the intestinal barrier's disruption and reduced serum, colon, and striatal pro-inflammatory cytokines, along with inhibiting the overactivation of glial cells, suggesting an inhibitory effect on inflammation from NaB throughout the gut-brain axis of the PD mice. Mechanistic studies revealed that NaB treatment suppressed the TLR4/MyD88/NF-kB pathway in the colon and striatum. In summary, NaB had a neuroprotective impact on the PD mice, likely linked to its regulation of gut microbiota to inhibit gut-brain axis inflammation.

Anti-inflammatory activity of Echinosophora koreensis nakai root extract in lipopolysaccharides-stimulated RAW 264.7 cells and carrageenan-induced mouse paw edema model

ETHNOPHARMACOLOGICAL RELEVANCE

Echinosophora koreensis Nakai is an endemic plant species distributed in a limited area within the Korean province of Gangwon, including the Yanggu-gun, Inje-gun, Cheorwon-gun, Chuncheon-si, and Hongcheon-gun counties. It is used in traditional medicine to treat various disorders, such as fever, skin diseases, diuresis, and neuralgia.

MATERIALS AND METHODS

This study demonstrated the effects of E. koreensis Nakai root extract (EKRE) on lipopolysaccharide (LPS)-induced inflammatory responses in vitro and in vivo. Cell viability was assessed through a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Nitric oxide (NO) production was measured using Griess reagent. Interleukin (IL)-6 and tumor necrosis factor (TNF) levels were assessed using enzyme-linked immunosorbent assays. Inducible nitric oxide synthase (iNOS), nuclear factor kappa-B (NF-κB), and mitogen-activated protein kinase (MAPK) expression were assessed using Western blot analysis. To examine the effects of EKRE in vivo, it was administered orally at doses of 50 or 200 mg/kg for 3 days in mice. Edema in the paws was induced through λ-carrageenan injection and measured hourly for up to 5 h using calipers.

RESULTS

EKRE markedly suppressed LPS-generated NO, IL-6, and iNOS production in RAW 264.7 cells. Moreover, it suppressed the activation of the NF-κB and MAPK in LPS-stimulated cells. Furthermore, EKRE significantly inhibited carrageenan-induced edema in mouse paws. There were no significant differences in IL-6 and TNF production in paw tissue harvested from mice, but levels decreased at high EKRE concentrations (200 mg/kg).

CONCLUSION

The results of this study provided validation for EKRE-induced inhibition of inflammatory responses in vitro and in vivo. This research suggested that EKRE is a promising treatment for inflammatory disorders.

Interplay of Gut Microbiota in Polycystic Ovarian Syndrome: Role of Gut Microbiota, Mechanistic Pathways and Potential Treatment Strategies

Polycystic Ovarian Syndrome (PCOS) comprises a set of symptoms that pose significant risk factors for various diseases, including type 2 diabetes, cardiovascular disease, and cancer. Effective and safe methods to treat all the pathological symptoms of PCOS are not available. The gut microbiota has been shown to play an essential role in PCOS incidence and progression. Many dietary plants, prebiotics, and probiotics have been reported to ameliorate PCOS. Gut microbiota shows its effects in PCOS via a number of mechanistic pathways including maintenance of homeostasis, regulation of lipid and blood glucose levels. The effect of gut microbiota on PCOS has been widely reported in animal models but there are only a few reports of human studies. Increasing the diversity of gut microbiota, and up-regulating PCOS ameliorating gut microbiota are some of the ways through which prebiotics, probiotics, and polyphenols work. We present a comprehensive review on polyphenols from natural origin, probiotics, and fecal microbiota therapy that may be used to treat PCOS by modifying the gut microbiota.

Novel Insight into the Mechanisms of Neurotoxicity Induced by 6:6 PFPiA through Disturbing the Gut-Brain Axis

As alternatives to traditional per- and polyfluoroalkyl substances, perfluoroalkyl phosphonic acids (PFPiAs) are frequently detected in aquatic environments, but the neurotoxic effects and underlying mechanisms remain unclear. In this study, male zebrafish were exposed to 6:6 PFPiA (1 and 10 nM) for 28 days, which exhibited anxiety-like symptoms. Gut microbiome results indicated that 6:6 PFPiA significantly increased the abundance of Gram-negative bacteria, leading to enhanced levels of lipopolysaccharide (LPS) and inflammation in the gut. The LPS was delivered to the brain through the gut-brain axis (GBA), damaged the blood-brain barrier (BBB), stimulated neuroinflammation, and caused apoptosis as well as neural injury in the brain. This mechanism was verified by the fact that antibiotics reduced the LPS levels in the gut and brain, accompanied by reduced inflammatory responses and anxiety-like behavior. The BBB damage also resulted in the enhanced accumulation of 6:6 PFPiA in the brain, where it might bind strongly with and activate aryl hydrocarbon receptor (AhR) to induce brain inflammation directly. Additionally, as the fish received treatment with an inhibitor of AhR, the inflammation response and anxiety-like behavior decreased distinctly. This study sheds light on the new mechanisms of neurotoxicity-induced 6:6 PFPiA due to the interruption on GBA.

Airway microbiome-immune crosstalk in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) has significantly contributed to global mortality, with three million deaths reported annually. This impact is expected to increase over the next 40 years, with approximately 5 million people predicted to succumb to COPD-related deaths annually. Immune mechanisms driving disease progression have not been fully elucidated. Airway microbiota have been implicated. However, it is still unclear how changes in the airway microbiome drive persistent immune activation and consequent lung damage. Mechanisms mediating microbiome-immune crosstalk in the airways remain unclear. In this review, we examine how dysbiosis mediates airway inflammation in COPD. We give a detailed account of how airway commensal bacteria interact with the mucosal innate and adaptive immune system to regulate immune responses in healthy or diseased airways. Immune-phenotyping airway microbiota could advance COPD immunotherapeutics and identify key open questions that future research must address to further such translation.

Pueraria lobata polysaccharides alleviate neonatal calf diarrhea by modulating gut microbiota and metabolites

Introduction

Neonatal calf diarrhea (NCD) is still one of the most critical diseases in calf rearing. Studies have shown that Pueraria lobata polysaccharides (PLP) have intense antioxidant and immunomodulatory activity and modulate gut microbiota. This randomized clinical trial aimed to determine the effect of PLP on the neonatal calf with diarrhea.

Methods

In this study, we recorded the fecal score of experimental calves, and calves with fecal scores ≥ 2 were determined as diarrhea and assessed their serum concentrations of inflammatory cytokines and oxidative damage-related indices. Fecal microbiota and metabolomics of diarrheal calves were further investigated.

Results

Results showed that treatment with PLP decreased the fecal score of diarrheal calves, serum concentrations of IL-1β, TNF-γ, and malondialdehyde, and also elevated the level of superoxide dismutase. In addition, PLP treatment altered the gut microbiota, significantly increased the relative abundances of beneficial bacteria, including the phyla Bacteroidetes and Actinobacteria, the genus Collinsella, Megamonas, and Bifidobacterium; decreased the relative abundances of pathogenetic or diarrhea related bacteria, such as Proteobacteria, Fusobacteria, Clostridium_sensu_stricto_1, and Escherichia_Shigella. Moreover, PLP can increase the fecal concentrations of isobutyric acid, propionic acid, and pantothenate; lower the levels of PC [18:0/18:1(9Z)], arachidonic acid, and docosahexaenoic acid.

Discussion

Thus, the results suggested that the PLP may perform the therapeutic activity via alleviating intestinal inflammation and regulating gut microbiota, avoiding further dysbiosis to restore the metabolism of gut microbiota, and finally promoting the recovery of diarrhea. The change further mitigated intestinal inflammation and oxidative damage in diarrheal calves. This indicated that PLP might be a promising treatment to attenuate diarrhea in neonatal calves.

Araceae root and citrus fibers tend to decrease Escherichia coli adhesion and myeloperoxidase levels in weaned piglets

Introduction

Weaning is a stressful experience in the piglet's life, and it often coincides with impaired gut health. Post-weaning diarrhea in piglets is frequently caused by enterotoxigenic Escherichia coli (E. coli). The first step of an E. coli infection is the adhesion to host-specific receptors present on enterocytes, leading to pro-inflammatory immune responses. The aim of this study was to examine if specific fiber fractions in the piglet diet can prevent E. coli adhesion and subsequent immune responses.

Methods

The trial included 200 piglets (Danbred × Piétrain): 10 piglets/pen × 10 pens/dietary treatment × 2 dietary treatments. From weaning until 14 days (d14) post-weaning, piglets were fed a control diet or test diet with 2 kg/ton of a mixture of specific fiber fractions derived from Araceae root and citrus. Afterwards, 1 piglet per pen was euthanized, a section was taken at 75% of small intestinal length and E. coli colonization on the mucosal epithelium was quantified by scraping and conventional plating. From the same small intestinal section, histo-morphological indices were assessed, and mucosal scrapings were analyzed for gene expression of pro- and anti-inflammatory cytokines, and NF-kB. Analyses of specific intestinal bacteria and SCFA were performed on samples of intestinal content (small intestine, caecum, colon). Fecal samples were taken to measure myeloperoxidase (MPO), calprotectin and PAP/RAG3A as biomarkers for intestinal inflammation.

Results and discussion

Piglets fed the fiber mixture tended to have decreased E. coli colonization to the mucosal epithelium (5.65 vs. 4.84 log10 CFU/g; P = 0.07), less E. coli in the caecum (8.91 vs. 7.72 log10 CFU/g; P = 0.03) and more Lachnospiraceae in the colon (11.3 vs. 11.6 log10 CFU/g; P = 0.03). Additionally, the fiber mixture tended to increase cecal butyric acid (10.4 vs. 19.1 mmol/kg; P = 0.07). No significant effect on histo-morphological indices and on gene expression of pro- and anti-inflammatory cytokines and NF-kB was observed. The fecal MPO concentration tended to decrease (20.2 vs. 10.4 ng/g; P = 0.07), indicating less intestinal inflammation. In conclusion, this study showed that specific fiber fractions from Araceae root and citrus in piglet weaner diets may decrease the risk of pathogen overgrowth by reducing E. coli adhesion and intestinal inflammation.

Environmental influences on childhood asthma-The effect of diet and microbiome on asthma

Early life dietary patterns and timely maturation of mucosa-associated microbial communities are important factors influencing immune development and for establishing robust immune tolerance networks. Microbial fermentation of dietary components in vivo generates a vast array of molecules, some of which are integral components of the molecular circuitry that regulates immune and metabolic functions. These in turn protect against aberrant inflammatory processes and promote effector immune responses that quickly eliminate pathogens. Multiple studies suggest that changes in dietary habits, altered microbiome composition, and microbial metabolism are associated with asthma risk and disease severity. While it remains unclear whether these microbiome alterations are a cause or consequence of dysregulated immune responses, there is significant potential for using diet in targeted manipulations of the gut microbiome and its metabolic functions in promoting immune health. In this article, we will summarize our knowledge to date on the role of dietary patterns and microbiome activities on immune responses within the airways. Given the malleability of the human microbiome, its integration into the immune system, and its responsiveness to diet, this makes it a highly attractive target for therapeutic and nutritional intervention in children with asthma.

Genetics and Nutrition Drive the Gut Microbiota Succession and Host-Transcriptome Interactions through the Gilthead Sea Bream (Sparus aurata) Production Cycle

Fish genetically selected for growth (GS) and reference (REF) fish were fed with CTRL (15% FM, 5-7% FO) or FUTURE (7.5% FM, 10% poultry meal, 2.2% poultry oil + 2.5% DHA-algae oil) diets during a 12-months production cycle. Samples from initial (t0; November 2019), intermediate (t1; July 2020) and final (t2; November 2020) sampling points were used for Illumina 16S rRNA gene amplicon sequencing of the adherent microbiota of anterior intestine (AI). Samples from the same individuals (t1) were also used for the gene expression profiling of AI by RNA-seq, and subsequent correlation analyses with microbiota abundances. Discriminant analyses indicated the gut bacterial succession along the production cycle with the proliferation of some valuable taxa for facing seasonality and different developmental stages. An effect of genetic background was evidenced along time, decreasing through the progression of the trial, namely the gut microbiota of GS fish was less influenced by changes in diet composition. At the same time, these fish showed wider transcriptomic landmarks in the AI to cope with these changes. Our results highlighted an enhanced intestinal sphingolipid and phospholipid metabolism, epithelial turnover and intestinal motility in GS fish, which would favour their improved performance despite the lack of association with changes in gut microbiota composition. Furthermore, in GS fish, correlation analyses supported the involvement of different taxa with the down-regulated expression of pro-inflammatory markers and the boosting of markers of extracellular remodelling and response to bacterium. Altogether, these findings support the combined action of the gut microbiome and host transcriptionally mediated effects to preserve and improve gut health and function in a scenario of different growth performance and potentiality.

The PPARα Regulation of the Gut Physiology in Regard to Interaction with Microbiota, Intestinal Immunity, Metabolism, and Permeability

Peroxisome proliferator-activated receptor alpha (PPARα) is expressed throughout the mammalian gut: in epithelial cells, in the villi of enterocytes and in Paneth cells of intestinal crypts, as well as in some immune cells (e.g., lamina propria macrophages, dendritic cells) of the mucosa. This review examines the reciprocal interaction between PPARα activation and intestinal microbiota. We refer to the published data confirming that microbiota products can influence PPARα signaling and, on the other hand, PPARα activation is able to affect microbiota profile, viability, and diversity. PPARα impact on the broad spectrum of events connected to metabolism, signaling (e.g., NO production), immunological tolerance to dietary antigens, immunity and permeability of the gut are also discussed. We believe that the phenomena described here play a prominent role in gut homeostasis. Therefore, in conclusion we propose future directions for research, including the application of synthetic activators and natural endogenous ligands of PPARα (i.e., endocannabinoids) as therapeutics for intestinal pathologies and systemic diseases assumed to be related to gut dysbiosis.

Manipulation of the diet-microbiota-brain axis in Alzheimer's disease

Several studies investigating the pathogenesis of Alzheimer's disease have identified various interdependent constituents contributing to the exacerbation of the disease, including Aβ plaque formation, tau protein hyperphosphorylation, neurofibrillary tangle accumulation, glial inflammation, and the eventual loss of proper neural plasticity. Recently, using various models and human patients, another key factor has been established as an influential determinant in brain homeostasis: the gut-brain axis. The implications of a rapidly aging population and the absence of a definitive cure for Alzheimer's disease have prompted a search for non-pharmaceutical tools, of which gut-modulatory therapies targeting the gut-brain axis have shown promise. Yet multiple recent studies examining changes in human gut flora in response to various probiotics and environmental factors are limited and difficult to generalize; whether the state of the gut microbiota in Alzheimer's disease is a cause of the disease, a result of the disease, or both through numerous feedback loops in the gut-brain axis, remains unclear. However, preliminary findings of longitudinal studies conducted over the past decades have highlighted dietary interventions, especially Mediterranean diets, as preventative measures for Alzheimer's disease by reversing neuroinflammation, modifying the intestinal and blood-brain barrier (BBB), and addressing gut dysbiosis. Conversely, the consumption of Western diets intensifies the progression of Alzheimer's disease through genetic alterations, impaired barrier function, and chronic inflammation. This review aims to support the growing body of experimental and clinical data highlighting specific probiotic strains and particular dietary components in preventing Alzheimer's disease via the gut-brain axis.

Treadmill Exercise Modulates Intestinal Microbes and Suppresses LPS Displacement to Alleviate Neuroinflammation in the Brains of APP/PS1 Mice

Neuroinflammation occurs throughout the pathogenesis of Alzheimer’s disease (AD). Here, we investigated the effects of treadmill exercise on neuroinflammation in APP/PS1 transgenic AD mice and the potential involvement of microbe–gut–brain axis (MGB) mechanisms based on growing evidence that AD’s pathogenesis is correlated with a deterioration in the function of gut microbiota. APP/PS1 transgenic AD mice were subjected to 12 weeks of treadmill exercise, followed by spatial memory tests. After the behavioral study, the amyloid (Aβ) pathology, gut microbes and metabolites, bacterial lipopolysaccharide (LPS) displacement, and degree of neuroinflammation were analyzed. We found that this strategy of exercise enriched gut microbial diversity and alleviated neuroinflammation in the brain. Notably, exercise led to reductions in pathogenic bacteria such as intestinal Allobaculum, increases in probiotic bacteria such as Akkermansia, increased levels of intestine–brain barrier proteins, and attenuated LPS displacement. These results suggest that prolonged exercise can effectively modulate gut microbes and the intestinal barrier and thereby reduce LPS displacement and ultimately alleviate AD-related neuroinflammation.

SER-109: An Oral Investigational Microbiome Therapeutic for Patients with Recurrent Clostridioides difficile Infection (rCDI)

Clostridioides difficile infection (CDI) is classified as an urgent health threat by the Centers for Disease Control and Prevention (CDC), and affects nearly 500,000 Americans annually. Approximately 20−25% of patients with a primary infection experience a recurrence, and the risk of recurrence increases with subsequent episodes to greater than 40%. The leading risk factor for CDI is broad-spectrum antibiotics, which leads to a loss of microbial diversity and impaired colonization resistance. Current FDA-approved CDI treatment strategies target toxin or toxin-producing bacteria, but do not address microbiome disruption, which is key to the pathogenesis of recurrent CDI. Fecal microbiota transplantation (FMT) reduces the risk of recurrent CDI through the restoration of microbial diversity. However, FDA safety alerts describing hospitalizations and deaths related to pathogen transmission have raised safety concerns with the use of unregulated and unstandardized donor-derived products. SER-109 is an investigational oral microbiome therapeutic composed of purified spore-forming Firmicutes. SER-109 was superior to a placebo in reducing CDI recurrence at Week 8 (12% vs. 40%, respectively; p < 0.001) in adults with a history of recurrent CDI with a favorable observed safety profile. Here, we discuss the role of the microbiome in CDI pathogenesis and the clinical development of SER-109, including its rigorous manufacturing process, which mitigates the risk of pathogen transmission. Additionally, we discuss compositional and functional changes in the gastrointestinal microbiome in patients with recurrent CDI following treatment with SER-109 that are critical to a sustained clinical response.

Effects of inulin supplementation on inflammatory biomarkers and clinical symptoms of women with obesity and depression on a calorie-restricted diet: a randomised controlled clinical trial

Major depressive disorder (MDD) is regarded as an inflammatory disorder. Gut microbiota dysbiosis, observed in both MDD and obesity, leads to endotoxemia and inflammatory status, eventually exacerbating depressive symptoms. Manipulation of gut microbiota by prebiotics might help alleviate depression. The present study aimed to investigate the effects of inulin supplementation on psychological outcomes and biomarkers of gut permeability, endotoxemia, inflammation, and brain-derived neurotrophic factor (BDNF) in women with obesity and depression on a calorie-restricted diet. In a double-blind randomised clinical trial, forty-five women with obesity and MDD were allocated to receive 10 g/d of either inulin or maltodextrin for 8 weeks; all the patients followed a healthy calorie restricted diet as well. Anthropometric measures, dietary intakes, depression, and serum levels of zonulin, lipopolysaccharide (LPS), inflammatory biomarkers (TNF-α, IL-10, monocyte chemoattractant protein-1, toll-like receptor-4 and high-sensitivity C-reactive protein), and BDNF were assessed at baseline and end of the study. Weight and Hamilton Depression Rating Scale (HDRS) scores decreased in both groups; between-group differences were non-significant by the end of study (P = 0·333 for body weight and P = 0·500 for HDRS). No between-group differences were observed for the other psychological outcomes and serum biomarkers (P > 0·05). In this short-term study, prebiotic supplementation had no significant beneficial effects on depressive symptoms, gut permeability, or inflammatory biomarkers in women with obesity and depression.

Microbiome influences on neuro-immune interactions in neurodegenerative disease

Mounting evidence points to a role for the gut microbiome in a wide range of central nervous system diseases and disorders including depression, multiple sclerosis, Alzheimer's disease, Parkinson's disease, and autism spectrum disorder. Moreover, immune system involvement has also been implicated in these diseases, specifically with inflammation being central to their pathogenesis. In addition to the reported changes in gut microbiome composition and altered immune states in many neurological diseases, how the microbiome and the immune system interact to influence disease onset and progression has recently garnered much attention. This chapter provides a review of the literature related to gut microbiome influences on neuro-immune interactions with a particular focus on neurological diseases. Gut microbiome-derived mediators, including short-chain fatty acids and other metabolites, lipopolysaccharide, and neurotransmitters, and their impact on neuro-immune interactions as well as routes by which these interactions may occur are also discussed.

Gut microbiota: Linking nutrition and perinatal depression

Perinatal depression is a mood disorder that is reported in women during pregnancy (prenatal) and after childbirth (postnatal). The onset of perinatal depression is associated with changes in reproductive hormones, stress hormones and neurosteroids. These chemical compounds can be modulated by the gut microbiota, which may affect maternal mental health during the perinatal period via the gut-brain-axis. Recent studies suggest that nutritional and dietary interventions (vitamin D, ω-3 fatty acids, iron, and fiber) effectively prevent or mitigate maternal depression and anxiety, but their efficacy is confounded by various factors, including the gut microbiota. Probiotics are efficacious in maintaining microbiota homeostasis, and thus, have the potential to modulate the development of perinatal mood disorders, despite no evidence in human. Therefore, clinical trials are warranted to investigate the role of probiotic supplementation in perinatal depression and behavioral changes. This article reviews the interplay between nutrition, gut microbiota and mood and cognition, and the evidence suggesting that probiotics affect the onset and development of perinatal depression.

Lipopolysaccharide-Induced Immunological Tolerance in Monocyte-Derived Dendritic Cells

Bacterial lipopolysaccharides (LPS), also referred to as endotoxins, are major outer surface membrane components present on almost all Gram-negative bacteria and are major determinants of sepsis-related clinical complications including septic shock. LPS acts as a strong stimulator of innate or natural immunity in a wide variety of eukaryotic species ranging from insects to humans including specific effects on the adaptive immune system. However, following immune stimulation, lipopolysaccharide can induce tolerance which is an essential immune-homeostatic response that prevents overactivation of the inflammatory response. The tolerance induced by LPS is a state of reduced immune responsiveness due to persistent and repeated challenges, resulting in decreased expression of pro-inflammatory modulators and up-regulation of antimicrobials and other mediators that promote a reduction of inflammation. The presence of environmental-derived LPS may play a key role in decreasing autoimmune diseases and gut tolerance to the plethora of ingested antigens. The use of LPS may be an important immune adjuvant as demonstrated by the promotion of IDO1 increase when present in the fusion protein complex of CTB-INS (a chimera of the cholera toxin B subunit linked to proinsulin) that inhibits human monocyte-derived DC (moDC) activation, which may act through an IDO1-dependent pathway. The resultant state of DC tolerance can be further enhanced by the presence of residual E. coli lipopolysaccharide (LPS) which is almost always present in partially purified CTB-INS preparations. The approach to using an adjuvant with an autoantigen in immunotherapy promises effective treatment for devastating tissue-specific autoimmune diseases like multiple sclerosis (MS) and type 1 diabetes (T1D).

Prevotella: An insight into its characteristics and associated virulence factors

Prevotella species, a gram-negative obligate anaerobe, is commonly associated with human infections such as dental caries and periodontitis, as well as other conditions such as chronic osteomyelitis, bite-related infections, rheumatoid arthritis and intestinal diseases like ulcerative colitis. This generally harmless commensal possesses virulence factors such as adhesins, hemolysins, secretion systems exopolysaccharide, LPS, proteases, quorum sensing molecules and antibiotic resistance to evolve into a well-adapted pathogen capable of causing successful infection and proliferation in the host tissue. This review describes several of these virulence factors and their advantage to Prevotella spp. in causing inflammatory diseases like periodontitis. In addition, using genome analysis of Prevotella reference strains, we examined other putative virulence determinants which can provide insights as biomarkers and be the targets for effective interventions in Prevotella related diseases like periodontitis.

Chicken jejunal microbiota improves growth performance by mitigating intestinal inflammation

Background

Intestinal inflammation is prevalent in chicken, which results in decreased growth performance and considerable economic losses. Accumulated findings established the close relationship between gut microbiota and chicken growth performance. However, whether gut microbiota impacts chicken growth performance by lessening intestinal inflammation remains elusive.

Results

Seven-weeks-old male and female chickens with the highest or lowest body weights were significantly different in breast and leg muscle indices and average cross-sectional area of muscle cells. 16S rRNA gene sequencing indicated Gram-positive bacteria, such as Lactobacilli, were the predominant species in high body weight chickens. Conversely, Gram-negative bacteria, such as Comamonas, Acinetobacter, Brucella, Escherichia-Shigella, Thermus, Undibacterium, and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium were significantly abundant in low body weight chickens. Serum lipopolysaccharide (LPS) level was significantly higher in low body weight chickens (101.58 ± 5.78 ng/mL) compared with high body weight chickens (85.12 ± 4.79 ng/mL). The expression of TLR4, NF-κB, MyD88, and related inflammatory cytokines in the jejunum was significantly upregulated in low body weight chickens, which led to the damage of gut barrier integrity. Furthermore, transferring fecal microbiota from adult chickens with high body weight into 1-day-old chicks reshaped the jejunal microbiota, mitigated inflammatory response, and improved chicken growth performance.

Conclusions

Our findings suggested that jejunal microbiota could affect chicken growth performance by mitigating intestinal inflammation.

Integrated 16S rRNA gene sequencing and LC/MS-based metabolomics ascertained synergistic influences of the combination of acupuncture and NaoMaiTong on ischemic stroke

ETHNOPHARMACOLOGICAL RELEVANCE

Acupuncture is an effective therapy for ischemic stroke, which has been widely used in China and gradually accepted in more countries and regions recently. In addition, Chinese medicine also plays an important role in stroke treatment, among which NaoMaiTong (NMT) is an example of an effective herbal formula for the treatment of stroke. A therapeutic strategy that combines acupuncture and medicine was widely used in stroke patients. However, the synergistic influences and mechanisms of combined acupuncture and medicine on ischemic stroke have not yet been entirely elucidated.

AIM OF THIS STUDY

The purpose of this study is to explore whether acupuncture and medicine combination treatments can produce synergism by using NMT, a clinically effective Chinese medicinal formula for the treatment of ischemic stroke for decades and has been demonstrated to be effective against ischemic brain injury, as a probe. Meanwhile, the potential mechanisms were investigated via cecal microbiome and plasma metabolomics to provide more strategies and basis for acupuncture-medicine combination for stroke.

MATERIALS AND METHODS

Adopted middle-cerebral artery occlusion/reperfusion (MCAO/R) rat models, the effect for the stroke of the combination treatment consisting of acupuncture and NMT was evaluated by detecting neurological issues, cerebral infarct dimensions, levels of inflammatory factors (IL-6, IL-1β, TNF-α) and oxidative stress factors (SOD, MDA) and brain-derived neurotrophic factor (BDNF). Subsequently,16S rRNA gene sequencing and LC/MS-based metabolomic analysis were utilized to explore the characteristics of cecal-contents microecology and plasma metabolic profile, respectively. Finally, the correlation between intestinal microecological characteristics and plasma metabolic characteristics was analyzed to explore the potential mechanism of the acupuncture-NMT combination.

RESULTS

The efficacy of acupuncture-NMT therapy was more effective than a single treatment on ischemic stroke, with more effectively reduced infarct sizes, improved neurobehavioral deficits, and alleviated oxidative stress and inflammatory responses. Besides, the combination therapy not only adjusted gut microbiota disturbances by enriching species diversity, reducing the abundance of pathogenic bacteria (such as Escherichia-Shaigella), as well as increasing the abundance of beneficial bacteria (such as Turicibacter, Bifidobacterium), but also improved metabolic disorders by reversing metabolite plasma levels to normality. The results of the correlation analysis demonstrated a significant association between intestinal microbiota and plasma metabolic profile, especially the strong correlation of Turicibacter and isoflavones phyto-estrogens metabolites.

CONCLUSION

The combination of acupuncture and NMT could produce synergism, suggesting acupuncture-medicine combination therapy might be more conducive to the recovery of ischemic stroke. And the potential mechanism was probably related to the mediation of intestinal microecology and plasma metabolism. Turicibacter and isoflavones phyto-estrogens metabolites might be the targets for acupuncture-NMT combination for stroke. Our current findings could provide a potential therapeutic strategy against ischemic stroke.