Diversity Of Intestinal Microbiota Research Articles

Lactic acid bacteria and yeast co-fermented milk alleviate cow milk allergy.

Cow milk allergy is one of the common food allergies. Our previous study showed that the allergenicity of fermented milk is lower than that of unfermented skimmed milk in vitro, and the antigenicity of β-lactoglobulin and α-lactalbumin in fermented milk was decreased by 67.54% and 80.49%, respectively. To confirm its effects in vivo, allergic BALB/C mice model was used to further study the allergenicity of fermented milk. It was found that compared with the skim milk (SM) group, the intragastrically sensitization with fermented milk had no obvious allergic symptoms and the fingers were more stable: lower levels of IgE, IgG, and IgA in serum, lower levels of plasma histamine and mast cell protein-1, and immune balance of Th1/Th2 and Treg/Th17. At the same time, intragastrically sensitization with fermented milk increased the α diversity of intestinal microbiota and changed the microbiota abundance: the relative abundance of norank-f-Muribaculaceae and Staphylococcus significantly decreased, and the abundance of Lachnospiraceae NK4A136 group, Bacteroides, and Turicibacter increased. In addition, fermented milk can also increase the level of short-chain fatty acids in the intestines of mice. It turns out that fermented milk is much less allergenicity than SM. PRACTICAL APPLICATION: Fermentation provides a theoretical foundation for reducing the allergenicity of milk and dairy products, thereby facilitating the production of low-allergenic dairy products suitable for individuals with milk allergies.

High-altitude-induced alterations in intestinal microbiota.

In high-altitude environments characterized by low pressure and oxygen levels, the intestinal microbiota undergoes significant alterations. Whether individuals are subjected to prolonged exposure or acute altitude changes, these conditions lead to shifts in both the diversity and abundance of intestinal microbiota and changes in their composition. While these alterations represent adaptations to high-altitude conditions, they may also pose health risks through certain mechanisms. Changes in the intestinal microbiota induced by high altitudes can compromise the integrity of the intestinal mucosal barrier, resulting in gastrointestinal dysfunction and an increased susceptibility to acute mountain sickness (AMS). Moreover, alterations in the intestinal microbiota have been implicated in the induction or exacerbation of chronic heart failure. Targeted modulation of the intestinal microbiota holds promise in mitigating high-altitude-related cardiac damage. Dietary interventions, such as adopting a high-carbohydrate, high-fiber, low-protein, and low-fat diet, can help regulate the effects of intestinal microbiota and their metabolic byproducts on intestinal health. Additionally, supplementation with probiotics, either through dietary sources or medications, offers a means of modulating the composition of the intestinal microbiota. These interventions may offer beneficial effects in preventing and alleviating AMS following acute exposure to high altitudes.

Yacon (Smallanthus sonchifolius) root extracts affect laying performance, egg quality, serum biochemical parameters and intestinal microbiota in hens.

The objective of this study was to investigate the influence of yacon root extracts (YREs) on productive performance and health of laying hens. Six hundred 30-week-old Xiaoshan Chicken layers were divided into 5 groups, control group, antibiotic positive control group, and 3 YREs treatment groups. In a 9-wk feeding experiment, at the end of wk 3, 6 and 9, twenty eggs were collected from each replicate to measure egg qualities. At the end of wk 9, three hen serum samples, and 5 hen cecal content samples were collected from each replicate. Compared to the control group, 0.8%, 1.6% and 2.4% YREs treatments could increase hens' daily feed intake, and YREs supplementation affected daily feed intake in linear manner. YREs did not change egg size, but 0.8% and 2.4% YREs changed egg shape by decreasing the egg shape index and sphericity, and 0.8% YREs tended to improve the eggshell breaking strength. 1.6% YREs might decrease yolk color grade but optimize the pH of thick egg white in fresh egg; moreover, 1.6% and 2.4% YREs might be helpful for eggs to inhibit water loss during storage, and YREs supplementation affected water loss rate in linear manner. 2.4% YREs could decrease the serum lactate dehydrogenases (LDH) level, and YREs supplemental levels linearly affected serum LDH content. Finally, YREs could enrich the diversity of intestinal microbiota of hens fed with 0.8% and be beneficial for the relative abundance of phylum Bacteroidota and Halobacterota; 2.4% YREs might increase the abundance of phylum Actinobacteriota and genus Bifidobacterium, while decrease genus Bacteroides; YREs supplemental levels affected the abundance of phylum Actinobacteriota, and genera Bifidobacterium and Bacteroides in linear manner. Dietary supplementation with YREs could affect egg quality, protect the health of organs and exhibit prebiotic activity.

Characterization of gut microbiota in patients with stage 3-4 chronic kidney disease: a retrospective cohort study.

Multiple factors, such as dietary patterns, pharmaceutical interventions, and exposure to harmful substances, possess the capacity to influence gut microbiota composition. Gut microbiota dysbiosis has emerged as a significant contributor to the progression of chronic kidney disease (CKD) and its associated complications. By comprehending the intricacies of the intestinal microbiota, this research endeavor holds the potential to offer novel perspectives on potential strategies for mitigating CKD progression. In this retrospective analysis, we assessed gut microbiota composition in CKD patients. Fecal samples were collected from a cohort of 44 patients with stage 3-4 CKD, alongside a control group consisting of 132 healthy volunteers. Subsequently, 16s rDNA sequencing was conducted to examine the composition of the gut microbiota. Our findings revealed significant alterations in the diversity of intestinal microbiota in fecal samples between patients with stage 3-4 CKD and healthy subjects. Among the 475 bacterial genera, 164 were shared, while 242 dominant genera were exclusive to healthy subjects and 69 to CKD stages 3-4 samples. Notably, healthy volunteers exhibited a prevalence of intestinal Firmicutes and Bacteroidetes, whereas stage 3-4 CKD patients displayed higher abundance of Proteobacteria and Actinobacteria. The presence of uncultured Coprobacillus sp. notably contributed to distinguishing between the two groups. ROC curve analysis identified distinct microbiota with superior diagnostic efficacy for discriminating stage 3-4 CKD patients from healthy individuals. Metabolic pathway analysis revealed differing dominant pathways between the two groups-the NADH dehydrogenase pathway in healthy individuals and the phosphate acetyltransferase pathway in stage 3-4 CKD patients. Moreover, the CKD cohort displayed a higher proportion of Gram-negative bacteria and facultative anaerobes. In conclusion, our study underscores the profound influence of gut microbiota dysbiosis on CKD progression. The distinct microbial profiles observed in CKD patients highlight the potential efficacy of microbiota-based interventions in mitigating CKD advancement.

Analysis of the characteristics of intestinal microbiota after oral tolerance in infants with food protein-induced proctocolitis.

To understand the characteristics of the intestinal microbiota after oral tolerance in infants with food protein-induced proctocolitis (FPIAP) treated with amino acid formula and their differences from healthy children, aiming to provide a scientific basis for guiding the application of probiotics during treatment. FPIAP infants were prospectively enrolled, fecal specimens were obtained, and DNA was extracted for PCR amplification of the bacterial 16S rRNA gene V4 region. Library construction and sequencing were performed, and bioinformatic analysis was performed after obtaining valid data. There were 36 patients in the FPIAP group: 20 males and 16 females, age 21.944 ± 13.277 months. Diarrhea with blood in the stool were the main symptom, with an average course of 14.83 ± 9.33 days. Thirty infants (83.33%) had mucus stool, 11.11% (4/36) of them experiencing vomiting, and 55.56% (20/36) of the infants displaying poor intake and weight gain, 28 (77.78%) patients with moderate eczema, 2 (5.6%) patients with chronic respiratory symptoms. The treatment time with amino acid formula was 5.51 ± 2.88 months. A control group comprising of 25 healthy infants who were full-term, natural delivery, bottle fed, and matched in terms of age (24.840 ± 12.680 months) and gender (15 males and 10 females) was selected. Anaerobic bacteria were less abundant in FPIAP infants than healthy infants (P = 4.811 × 10-5), but potentially pathogenic bacteria were more abundant (P = 0.000). The abundance of Actinobacteria was low in FPIAP infants, the abundance of Proteobacteria was high, and the abundance of Firmicutes was reduced. Bifidobacterium could be used as a bacterial genus to differentiate healthy and FPIAP infants. Both α-and β-diversity indicators of intestinal microbiota were lower in FPIAP infants. In FPIAP infants, glucose and energy metabolism and amino acid anabolism were decreased, and inflammation-related lipopolysaccharide synthesis pathways were increased. Compared with healthy infants, FPIAP infants with oral tolerance after amino acid formula treatment had differences in the structure and diversity of intestinal microbiota, among which Bifidobacterium was significantly reduced. This trial was registered on https://register.clinicaltrials.gov/.

Intestinal microbiota diversity from broilers with runting and stunting syndrome performed by metagenomics

ABSTRACT Runting and stunting syndrome (RSS) is an enteric viral disease in commercial poultry that directly affects gut health; however, its influence on gut microbiota remains unknown. This study aimed to investigate the compositional changes in the bacterial community of the ileum of 7-day-old broiler chicks naturally affected and not affected by RSS, using next-generation sequencing (NGS) technology. Twenty-one samples were obtained from the ileal contents and mucosa of 11 chicks with RSS and 10 healthy chicks, raised in a dark house system located on a farm in the state of Minas Gerais, Brazil. The results revealed overall changes in the gut microbiota of the chicks with RSS, including a decrease in microbial richness and diversity. In particular, there was a decrease in Lactobacillus and an increase in Candidatus Arthromitus and Clostridium sensu stricto 1. These results indicate a relationship between viral infection and the gut microbial composition, which can cause gut dysbiosis and may influence inflammation in this organ. RESEARCH HIGHLIGHTS RSS causes dysbiosis of the gut microbiota of the ilea of chicks. A difference was found in gut microbiota between chicks with and without RSS. Candidatus Arthromitus was predominant in chicks with RSS. Clostridium sensu stricto 1 was strictly associated with chicks with RSS.

Whole-plant silage maize to improve fiber digestive characteristics and intestinal microbiota of Hezuo pigs.

Utilizing roughage resources is an effective approach to alleviate the shortage of corn-soybean feed and reducing the costs in the swine industry. Hezuo pig is one group of plateau type local Tibetan pig with strong tolerance to crude feeding. Nevertheless, current research on the roughage tolerance in Hezuo pigs and the microbiological mechanisms behind it is still minimally.This study explored the impact of various ratios of whole-plant silage (WPS) maize on the pH, cellulase activity, short-chain fatty acids (SCFAs), and intestinal microbiota in Hezuo pigs. Thirty-two Hezuo pigs were randomly divided into four groups (n = 8). The control group received a basal diet, while experimental groups I, II, and III were given diets with incremental additions of 5%, 10%, and 15% air-dried WPS maize, respectively, for 120 days. The findings revealed that compared with the control group, in Group II, the pH of cecum and colon were notably decreased (p < 0.05), while acid detergent fiberdigestibility, the concentration of propionic and isobutyric acid in the cecum, and the concentration of isobutyric acid in the colon were significantly increased (p < 0.05). Also, carboxymethyl cellulase activity in the cecum in group II of Hezuo pigs was significantly higher than that in the other three groups (p < 0.05). Furthermore, the cecum microbiota showed a higher diversity in the group II of Hezuo pigs than that in the control group, as shown by the Simpson and Shannon indices. Specifically, 15 and 24 bacterial species showed a significant difference in relative abundance at the family and genus levels, respectively. Correlation analyses revealed significant associations between bacterial genera and SCFAs concentrations in the cecum. The abundance of Bacteroides and NK4A214_group was positively correlated with amounts of valeric and isovaleric acid but negatively with propionic acid (p < 0.05). The abundance of UCG-010 was positively linked with acetic acid and negatively correlated with butyric acid (p < 0.05). Actinobacillus abundance was positively associated with butyric acid levels (p < 0.05). In conclusion, a 10% WPS maize diet improved crude fiber digestibility by lowering cecal and colonic chyme pH, enhancing intestinal cellulase activity, improving SCFA production, and increasing intestinal microbiota diversity.

Interaction of Trypanosoma cruzi, Triatomines and the Microbiota of the Vectors-A Review.

This review summarizes the interactions between Trypanosoma cruzi, the etiologic agent of Chagas disease, its vectors, triatomines, and the diverse intestinal microbiota of triatomines, which includes mutualistic symbionts, and highlights open questions. T. cruzi strains show great biological heterogeneity in their development and their interactions. Triatomines differ from other important vectors of diseases in their ontogeny and the enzymes used to digest blood. Many different bacteria colonize the intestinal tract of triatomines, but only Actinomycetales have been identified as mutualistic symbionts. Effects of the vector on T. cruzi are indicated by differences in the ability of T. cruzi to establish in the triatomines and in colonization peculiarities, i.e., proliferation mainly in the posterior midgut and rectum and preferential transformation into infectious metacyclic trypomastigotes in the rectum. In addition, certain forms of T. cruzi develop after feeding and during starvation of triatomines. Negative effects of T. cruzi on the triatomine vectors appear to be particularly evident when the triatomines are stressed and depend on the T. cruzi strain. Effects on the intestinal immunity of the triatomines are induced by ingested blood-stage trypomastigotes of T. cruzi and affect the populations of many non-symbiotic intestinal bacteria, but not all and not the mutualistic symbionts. After the knockdown of antimicrobial peptides, the number of non-symbiotic bacteria increases and the number of T. cruzi decreases. Presumably, in long-term infections, intestinal immunity is suppressed, which supports the growth of specific bacteria, depending on the strain of T. cruzi. These interactions may provide an approach to disrupt T. cruzi transmission.

Effect of prednisolone in a kindling model of epileptic seizures in rats on cytokine and intestinal microbiota diversity

Epilepsy is a neurological disease characterized by spontaneous and recurrent seizures. Epileptic seizures can be initiated and facilitated by inflammatory mechanisms. As the dysregulation of the immune system would be involved in epileptogenesis, it is suggested that anti-inflammatory medications could impact epileptic seizures. These medications could potentially have a side effect by altering the structure and composition of the intestinal microbiota. These changes can disrupt microbial homeostasis, leading to dysbiosis and potentially exacerbating intestinal inflammation. We hypothesize that prednisolone may affect the development of epileptic seizures, potentially influencing the diversity of the intestinal microbiota and the regulation of pro-inflammatory cytokines in intestinal tissue. This study aimed to evaluate the effects of prednisolone treatment on epileptic seizures and investigate the effect of this drug on the bacterial diversity of the intestinal microbiota and markers of inflammatory processes in intestinal tissue. We used Male Wistar rat littermates (n = 31, 90-day-old) divided into four groups: positive control treated with 2 mg/kg of diazepam (n = 6), negative control treated with 0.9 g% sodium chloride (n = 6), and the remaining two groups were subjected to treatment with prednisolone, with one receiving 1 mg/kg (n = 9) and the other 5 mg/kg (n = 10). All administrations were performed intraperitoneally (i.p.) over 14 days. To induce the chronic model of epileptic seizures, we administered pentylenetetrazole (PTZ) 25 mg/kg i.p. on alternate days. Seizure latency (n = 6 – 10) and TNF-α and IL-1β concentrations from intestinal samples were measured by ELISA (n = 6 per group), and intestinal microbiota was evaluated with intergenic ribosomal RNA (rRNA) spacer (RISA) analysis (n = 6 per group). The prednisolone treatment demonstrated an increase in the latency time of epileptic seizures and TNF-α and IL-1β concentrations compared to controls. There was no statistically significant difference in intestinal microbiota diversity between the different treatments. However, there was a strong positive correlation between microbial diversity and TNF-α and IL-1β concentrations. The administration of prednisolone yields comparable results to diazepam on increasing latency between seizures, exhibiting promise for its use in clinical studies. Although there were no changes in intestinal microbial diversity, the increase in the TNF-α and IL-1β cytokines in intestinal tissue may be linked to immune system signaling pathways involving the intestinal microbiota. Additional research is necessary to unravel the intricacies of these pathways and to understand their implications for clinical practice.

Phlorizin Limits Bovine Viral Diarrhea Virus Infection in Mice via Regulating Gut Microbiota Composition.

Phlorizin (PHZ) is one of the main pharmacologically active ingredients in Lithocarpus polystachyus. We have previously shown that PHZ inhibits the replication of bovine viral diarrhea virus (BVDV), but the exact antiviral mechanism, especially in vivo, is still unknown. Here, we further confirm that PHZ has good protective effects in BVDV-infected mice. We analyzed BVDV-induced CD3+, CD4+, and CD8+ T cells among peripheral blood lymphocytes and found that PHZ significantly restored their percentage. Metagenomic analyses revealed that PHZ markedly improved the richness and diversity of intestinal microbiota and increased the abundance of potentially health-related microbes (families Lachnosipiraceae, Ruminococcaceae, and Oscillospiraceae). Specifically, the relative abundance of short chain fatty acid (SCFA)-producing bacteria, including Lachnospiraceae_UCG-006, unclassified_f_Ruminococcaceae, Oscillibacter, Intestinimonas, Blautia, and Lachnoclostridium increased significantly after PHZ treatment. Interestingly, BVDV-infected mice that received fecal microbiota from PHZ-treated mice (PHZ-FMT) had a significantly lower viral load in the duodenum and jejunum than untreated mice. Pathological lesions of duodenum and jejunum were also greatly reduced in the PHZ-FMT group, confirming a significant antiviral effect. These findings show that gut microbiota play an important role in PHZ's antiviral activity and suggest that their targeted intervention might be a promising endogenous strategy to prevent and control BVDV.

The role of dietary Clostridium autoethanogenum protein in the growth, disease resistance, intestinal health and transcriptome response of Pacific white shrimp under different stocking densities

With the rapid development of intensive farming mode and the high price of fishmeal (FM), finding alternatives to FM and exploring the application under different stocking densities has become a focus of current research in aquaculture. In this research, the ability of Pacific white shrimp (Litopenaeus vannamei) to utilize Clostridium autoethanogenum protein (CAP) at different stocking densities was investigated from the aspects of growth, disease resistance, intestinal health and transcriptome response. A 3 × 2 factorial design stocking experiment was conducted, using L. vannamei fed diets of two protein sources (FM and CAP) at three stocking densities with 100 per m3 (low, LSD), 200 per m3 (medium, MSD) and 300 per m3 (high, HSD) for 8 weeks. At the end of the feeding trail, the growth performance and the resistance to Vibrio parahaemolyticus of shrimp decreased with the increase of stocking density, and dietary CAP could promote the effects at the same stocking density when compared with the FM group, with more notable enhancement effect at high stocking density was observed. There was a significant interaction between stocking density and protein source on the activities of alkaline phosphatase (AKP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), catalase (CAT), superoxide dismutase (SOD), lysozyme (LYS), amylase and lipase, most of which were significantly different between CAP and FM groups only at high stocking density. Analysis of 16S rDNA sequencing showed that dietary CAP increased the alpha diversity of intestinal microbiota, inhibited the colonization of pathogenic bacteria and enhanced the abundance of beneficial bacteria. Transcriptomics results showed that DEGs in the FM vs CAP group at the same stocking densities were mainly enriched in immune and metabolism-related pathways including Toll and Imd, PI3K-Akt, and JAK/STAT signaling pathway. Pearson correlation analysis revealed significant correlation between the top ten intestinal bacteria at the genus level and markedly enriched DEGs, also more were detected under high density situations. In conclusion, dietary CAP could not only promote the growth of shrimp, but also improves the immunity and metabolism, and maintains the intestinal health of shrimp when compared with dietary FM, along with more pronounced improvement effect at high-density stocking. The results implied that CAP had a great potential as a novel protein source in shrimp intensive aquaculture.

Gamma ray irradiation enhances defatted Hermetia illucens larvae meal as a dietary alternative to fishmeal for Acanthopagrus schlegelii juveniles

The current research investigated whether gamma (γ)-irradiation could improve the viability of defatted Hermetia illucens larvae (HIL) meal as a fishmeal alternative in black sea bream (Acanthopagrus schlegelii) diets. Three diets were formulated with equal protein (420 g/kg) and lipid (80 g/kg) contents. A diet containing 400 g/kg fishmeal was served as the control diet (C), and 50% of fishmeal in diet C was replaced by either defatted HIL meal or γ-irradiated defatted HIL meal to produce diet HR and diet HR10, respectively. Fish fed diet HR exhibited lower final body weight and weight gain compared to those fed diet C, while no statistically significant differences were found between fish fed diets C and HR10. Additionally, fish fed diet HR10 exhibited significantly lower feed intake, feed conversion rate, nitrogen waste, hepatic malondialdehyde content, relative usage of fishmeal and fish oil, fish-in to fish-out ratio, and economic conversion ratio, and meanwhile significantly higher nitrogen retention efficiency, hepatic total antioxidant capacity, economic profitability index and profitability, than those fed diet C. Fish fed different test diets showed statistically equal alpha diversity of intestinal microbiota, whereas the beta diversity of intestinal microbiota in group HR was far from groups C and HR10. Compared to fish fed diet C, the gut microbiota composition of fish fed diet HR showed significant alterations at both the phylum and genus levels. However, the altered composition of intestinal bacteria was partially restored in fish fed diet HR10. The above findings indicate that treating defatted HIL meal with γ-ray can reduce dietary fishmeal content for black sea bream to 200 g/kg without any adverse effects on growth, proximate composition and intestinal microbial diversity, and meanwhile ameliorates the feed utilization, hepatic antioxidant capacity, and intestinal microbiological composition of black sea bream. Furthermore, feeding γ-irradiated defatted HIL meal enhances the economic profitability, while reduces the waste output and reliance on fishery resource of black sea bream aquaculture.

Exploring the sex dimorphism in the expression of intestinal barrier and immune-related genes and intestinal microbiota in cage-cultured large yellow croaker (Larimichthys crocea) during the overwintering period along the Zhoushan coast

In Zhejiang province, large yellow croakers are primarily cultured in net cages, facing significant challenges during the overwintering period such as susceptibility to cold and starvation stress. Notably, the observable sexual dimorphism in the large yellow croaker hints at the likelihood of gender differences in their responses to these environmental stresses. However, the potential sex-specific adaptive changes during overwintering remain unexplored. To gain deeper insights, we investigated the expression of intestinal barrier-related genes, immune responses, and changes in intestinal microbiota during the overwintering period in males and females separately. The results revealed a more pronounced loss of body weight in females than that in males. In male intestines, there was a significant decrease in the expression of intestinal barrier-related genes (arp2/3, occludin, and zo1), contrasting with a significant increase in females. The expression of TLR1, TLR3, TLR7, TLR9, MyD88, and NF-κB genes in the intestines of female fish decreased significantly in March compared to November, while the opposite trend was observed in male fish. However, in the liver, TLR1, TLR3, TLR7, TLR9, MyD88, and NF-κB genes expression were both decreased significantly in males and females. In the male intestines, there was a significant increase in the expression of inflammatory cytokine genes (IL-1β and IL-6). In the females, IL-1β gene expression significantly decreased, while IL-6 expression increased significantly. The expression of IL-10 genes decreased in both males and females. In the liver, both the males and females exhibited a significant increase in the expression of IL-1β and IL-6 genes. Further analysis revealed greater susceptibility of male intestinal microbiota diversity during the overwintering period. Firmicutes’ relative abundance exhibited opposing changes between the males and females, and Proteobacteria abundance, driven by a significant increase in Vibrio bacteria, significantly increased in the males. In conclusion, the overwintering period may compromise the structural integrity of male fish intestines, reducing their immune function. Additionally, the response strategy of the intestinal microbiota differs between sexes. The findings provide crucial insights for crafting effective strategies and management decisions in cage-cultured large yellow croaker during the overwintering period, as well as offering theoretical references for monosex aquaculture.

Dietary apidaecin Api-PR19 addition improves growth performance, intestinal health and modulating gut microbiota in broilers.

This study investigated the effects of Apidaecin Api-PR19 as feed additive on growth performance, intestinal health, and small intestinal microbiota of broilers. A total of 360 1-d-old Arbor Acres broilers were randomly assigned to 3 groups with 6 replicates including control group with basal diet (CON), antibiotic growth promotor group with basal plus 10 mg/kg colistin sulfate and 50mg/kg roxarsone (AGP), and antibacterial peptide group with basal diet plus 330 mg/kg Apidaecin Api-PR19 (ABP). The trial lasted 35 d. Results showed that dietary Api-PR19 addition increased (p＜0.05) the average daily feed intake (ADFI), average daily gain (ADG) and decreased (p＜0.05) feed conversion ratio (FCR) during 1 to 21 d compared with the CON group. The digestibility of dry matter and crude protein were higher in AGP and ABP groups (p＜0.05) where greater trypsin activity was detected in duodenum (p＜0.05). The ratio of villus height to crypt depth (V/R) in duodenum and jejunum was increased at 35 d when broilers were given diets with ABP or AGP (p＜0.05). Besides, ABP treatments up-regulated (p＜0.05) the mRNA expression of EAAT3, GLUT2, ZO-1 and Claudin-1 in duodenum of broilers at 35 d of age. The results of immunohistochemistry showed that ABP treatment significantly increased (p＜0.05) duodenal sIgA content. In addition, 16S rRNA gene sequencing revealed that there were differences in the intestinal microbiota diversity and composition among three groups. Notably, the linear discriminant analysis effect size (LEfSe) showed that p_Firmicutes, g_Enterococcus, g_Carnobacterium, g_Kitasatospora and g_Acidaminococcus were dominant in ABP group. Redundancy analysis showed that these changes in gut microbiota in ABP group had correlation with growth performance, intestinal morphology, and content of sIgA. In general, these results indicated that dietary 330 mg/kg Apidaecin Api-PR19 supplementation promoted growth performance of broilers by improving intestinal development, nutrients absorption, immune function and modulating intestinal microbiota.

New insights into the interactions between the gut microbiota and the inflammatory response to ulcerative colitisin a mouse model of dextran sodium sulfate and possible mechanisms of action for treatment with PE&AFWE.

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is a heterogeneous state of chronic intestinal inflammation. Intestinal innate immunity, including innate immune cells, defends against pathogens and excessive entry of gut microbiota, while preserving immune tolerance to resident intestinal microbiota, and may be characterized by its capacity to produce a rapid and nonspecific reaction. The association between microbiota dysbiosis and the pathogenesis of IBD is complex and dynamic. When the intestinal ecosystem is in dysbiosis, the reduced abundance and diversity of intestinal gut microbiota make the host more vulnerable to the attack of exogenous and endogenous pathogenic gut microbiota. The aim of our study was to comprehensively assess the relationship between microbial populations within UC, the signaling pathways of pathogenic gut microbe therein and the inflammatory response, as well as to understand the effects of using PE&AFWE (poppy extract [Papaver nudicaule L.] and Artemisia frigida Willd. extract) on UC modulation. A UC mouse model was established by inducing SPF-grade C57BL/6 mice using dextrose sodium sulfate (DSS). Based on metagenomic sequencing to characterize the gut microbiome, the relationship between gut microbiota dysbiosis and gut microbiota was further studied using random forest and Bayesian network analysis methods, as well as histopathological analysis. (1) We found that the 5 gut microbiota with the highest relative abundance of inflammatory bowel disease UC model gut microbiota were consistent with the top 5 ranked natural bacteria. There were three types of abundance changes in the model groups: increases (Chlamydiae/Proteobacteria and Deferribacteres), decreases (Firmicutes), and no significant changes (Bacteroidetes). The UC model group was significantly different from the control group, with 1308 differentially expressed species with abundance changes greater than or equal to 2-fold. (2) The proportion of the fecal flora in the UC group decreased by 37.5% in the Firmicutes and increased by 14.29% in the proportion of Proteobacteria compared to the control group before treatment. (3) The significantly enriched and increased signaling pathways screened were the 'arachidonic acid metabolic pathway' and the 'phagosomal pathway', which both showed a decreasing trend after drug administration. (4) Based on the causal relationship between different OTUs and the UC model/PE&AFWE administration, screening for directly relevant OTU networks, the UC group was found to directly affect OTU69, followed by a cascade of effects on OTU12, OTU121, OTU93, and OTU7, which may be the pathway of action that initiated the pathological changes in normal mice. (5) We identified a causal relationship between common differentially expressed OTUs and PE&AFWE and UC in the pre- and post-PE&AFWE-treated groups. Thereby, we learned that PE&AFWE can directly affect OTU90, after which it inhibits UC, inhibiting the activity of arachidonic acid metabolic pathway by affecting OTU118, which in turn inhibits the colonization of gut microbiota by OTU93 and OTU7. (6) Histopathological observation and scoring (HS) of the colon showed that there was a significant difference between the model group and the control group (p < 0.001), and that there was a significant recovery in both the sulfasalazine (SASP)and the PE&AFWE groups after the administration of the drug (p < 0.0001). We demonstrated causal effects and inflammatory metabolic pathways in gut microbiota dysbiosis and IBD, with five opportunistic pathogens directly contributing to IBD. PE&AFWE reduced the abundance of proteobacteria in the gut microbiota, and histopathology showed significant improvement.

Gut microbially produced tryptophan metabolite melatonin ameliorates osteoporosis via modulating SCFA and TMAO metabolism.

Osteoporosis (OP)is a severe global health issue that has significant implications for productivity and human lifespan. Gut microbiota dysbiosis has been demonstrated to be closely associated with OP progression. Melatonin (MLT)is an important endogenous hormone that modulates bone metabolism, maintains bone homeostasis, and improves OP progression. Multiple studies indicated that MLT participates in the regulation of intestinal microbiota and gut barrier function. However, the promising effects of gut microbiota-derived MLT in OP remain unclear. Here, we found that OP resulted in intestinal tryptophan disorder and decreased the production of gut microbiota-derived MLT, while administration with MLT could mitigate OP-related clinical symptoms and reverse gut microbiota dysbiosis, including the diversity of intestinal microbiota, the relative abundance of many probiotics such as Allobaculum and Parasutterella, and metabolic function of intestinal flora such as amino acid metabolism, nucleotide metabolism, and energy metabolism. Notably, MLT significantly increased the production of short-chain fatty acids and decreased trimethylamine N-oxide-related metabolites. Importantly, MLT could modulate the dynamic balance of M1/M2 macrophages, reduce the serum levels of pro-inflammatory cytokines, and restore gut-barrier function. Taken together, our results highlighted the important roles of gut microbially derived MLT in OP progression via the "gut-bone" axis associated with SCFA metabolism, which may provide novel insight into the development of MLT as a promising drug for treating OP.

Combined intestinal microbiota and transcriptomic analysis to investigate the effect of different stocking densities on the ability of Pacific white shrimp (Litopenaeus vannamei) to utilize Chlorella sorokiniana

Aiming to investigate the impact of different stocking densities on the ability of Pacific white shrimp (Litopenaeus vannamei) to utilize Chlorella sorokiniana (CHL), a 3 × 2 factorial design stocking experiment was used in this study. Specifically, shrimp was fed with two dietary protein sources (fishmeal (FM) and CHL) at low (LSD, 100 per m³), medium (MSD, 200 per m³) and high (HSD, 300 per m³) stocking densities for 8 weeks. The growth performance and resistance to Vibrio parahaemolyticus (1.0 × 107 CFU per mL) of shrimp decreased with the increase of stocking density, but dietary CHL improved this result. Differences between the CHL and FM groups for V. parahaemolyticus resistance were significant only under high-density conditions (P < 0.05). Significant interactions between stocking density and protein source were found on the activities of catalase (CAT), superoxide dismutase (SOD) and phenol oxidase (PO), and the contents of malondialdehyde (MDA) in the hepatopancreas and the activities of intestinal amylase, most of which were significantly different between CHL and FM groups only at high stocking density (P < 0.05). Analysis of 16S rDNA sequencing showed that dietary CHL increased the alpha diversity of intestinal microbiota, inhibited the colonization of pathogenic bacteria and enhanced the abundance of beneficial bacteria. Transcriptomic results showed that at high stocking densities, differentially expressed genes (DEGs) in the FM vs CHL group were mostly upregulated and primarily enriched in immune and metabolic related pathways including Toll, immune deficiency (Imd) and glycolysis-gluconeogenesis pathways. Pearson correlation analysis revealed significant correlation between the top ten intestinal bacteria at the genus level and markedly enriched DEGs, also more were detected under high density situations. In conclusion, CHL has great potential as a novel protein source in the intensive farming of shrimp.

Effects of diet containing germinated faba bean (Vicia faba L.) on the intestinal health and gut microbial communities of Nile tilapia (Oreochromis niloticus)

Crisp Nile tilapia (Oreochromis niloticus) is a valuable fish product with high muscle firmness and chewiness generated by dietary faba beans (Vicia faba L.). However, the overconsumption of faba bean could induce intestinal inflammation in Nile tilapia due to its endogenous anti-nutritional factors (ANFs). Germination has been cited as an effective method for reducing ANFs in faba beans. But, the effects of germinated faba beans on the tilapia remain unclear. In this report, Nile tilapia were fed a diet supplemented with dry faba beans (FB0), or germinated faba beans (FB5), or a basal diet (control) for 75 days. Thereafter, samples of the fish were examined for textural quality, digestive enzyme activity, histology of the inner intestinal wall, expression of related genes, and composition of intestinal microbes. The hardest fillets were obtained from the FB5 (406.17 ± 42.51 gf) group, followed by the FB0 (301.17 ± 24.70 gf) and control (117.50 ± 8.19 gf) groups. The amylase levels were lower in the FB0 and FB5 groups, whereas the trypsin activities were up to 1.9-fold higher than in the control group. The gene expressions of IL-1β, CCL3, and TNF-α were significantly up-regulated in both the FB0 and FB5 groups, whereas metallothionein expression was down-regulated in the intestine relative to control group. Moreover, expression of IFN-γ and Hsp70 decreased in FB5, but increased in FB0. In particular, the diversity of intestinal microbiota was higher in the FB5 group than in the FB0 group (Fusobacteria abundance significantly decreased from 79.18% to 55.87%, while Proteobacteria abundance decreased from 8.12% to 7.02%), indicating that the intestinal microbiota structure was affected by altered diets. These results indicate that germinated faba bean could be a good substitute for dry faba beans in tilapia culture.

Dihydroartemisinin Protects Mice from CUMS-induced Depression-like Behaviors by Regulating Gut Microbes

Depression is one of the most common forms of psychopathology, which is associated with gut microbiota dysfunction. Dihydroartemisinin (DHA) has been shown to regulate gut microbiota and ameliorate neuropathies, but whether it can be used to treat depression remains unclear. Our study found that DHA treatment raised the preference for sugar water in chronic unpredictable mild stress (CUMS)-induced mice and reduced the immobility time in open field, forced swimming and tail suspension experiments, and promoted doublecortin expression. Additionally, DHA up-regulated the diversity and richness of intestinal microbiota in depression-like mice, and restored the abnormal abundance of microbiota induced by CUMS, such as Turicibacter, Lachnospiraceae, Erysipelotrichaceae, Erysipelatoclostridium, Eubacterium, Psychrobacter, Atopostipes, Ileibacterium, Coriobacteriacea, Alistipes, Roseburia, Rikenella, Eggerthellaceae, Ruminococcus, Tyzzerella, and Clostridia. Furthermore, KEGG pathway analysis revealed that gut microbiota involved in the process of depression may be related to glucose metabolism, energy absorption and transport, and AMPK signaling pathway. These results indicated that DHA may play a protective role in CUMS-induced depression by mediating gut-microbiome.

Fusobacteria alterations are associated with colorectal cancer liver metastasis and a poor prognosis.

Liver metastasis is a major cause of mortality in patients with advanced stages of colorectal cancer (CRC). The gut microbiota has been demonstrated to influence the progression of liver diseases, potentially providing novel perspectives for diagnosis, treatment and research. However, the gut microbial characteristics in CRC with liver metastasis (LM) and with no liver metastasis (NLM) have not yet been fully established. In the present study, high-throughput 16S RNA sequencing technology was employed, in order to examine the gut microbial richness and composition in patients with CRC with LM or NLM. A discovery cohort (cohort 2; LM=18; NLM=36) and a validation cohort (cohort 3; LM=13; NLM=41) were established using fresh feces. In addition, primary carcinoma tissue samples were also analyzed (LM=8 and NLM=10) as a supplementary discovery cohort (cohort 1). The findings of the present study indicated that the intestinal microbiota richness and diversity were increased in the LM group as compared to the NLM group. A significant difference was observed in species composition between the LM and NLM group. In the two discovery cohorts with two different samples, the dominant phyla were consistent, but varied at lower taxonomic levels. Phylum Fusobacteria presented consistent and significant enrichment in LM group in both discovery cohorts. Furthermore, with the application of a random forest model and receiver operator characteristic curve analysis, Fusobacteria was identified as a potential biomarker for LM. Moreover, Fusobacteria was also a poor prognosis factor for survival. Importantly, the findings were reconfirmed in the validation cohort. On the whole, the findings of the present study demonstrated that CRC with LM and NLM exhibit distinct gut microbiota characteristics. Fusobacteria detection thus has potential for use in predicting LM and a poor prognosis of patients with CRC.