Abundance Of Intestinal Microbiota Research Articles

The Gut Microbiota and Its Relevance to Peripheral Lymphocyte Subpopulations and Cytokines in Patients with Rheumatoid Arthritis.

Growing experimental and clinical evidence suggests that a chronic inflammatory response induced by gut microbiome critically contribute to the development of rheumatoid arthritis (RA). Previous studies demonstrated the disturbance of lymphocyte subpopulations in RA patients. The purpose of this study was to explore the characteristics of gut microbiome and the associations between bacterium and lymphocyte subpopulations as well as cytokines in patients with RA. Fecal samples from 205 RA patients and 199 healthy controls (HCs) were collected for bacterial DNA extraction and 16S ribosomal RNA (rRNA) gene sequencing. The levels of peripheral lymphocyte subpopulation such as T, B, CD4+T, CD8+T, NK, T helper 1 (Th1), Th2, Th17, and regulatory T cells (Tregs) of these subjects were detected by flow cytometry combined with standard absolute counting beads. The serum levels of cytokines interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-17, tumour necrosis factor-α (TNF-α), and interferon-γ (INF-γ) were tested by flow cytometric bead array (CBA). Alpha and beta diversity of gut microbiome were explored by bioinformatics analysis. Spearman rank correlation test was used to explore the relationships between gut microbiome and lymphocyte subsets as well as serum cytokines. The diversity and relative abundance of intestinal microbiota in patients with RA were significantly different from those in HCs. Detailly, the abundant of phylum Proteobacteria in RA patients was more than that in HCs, while Firmicutes was less than in HCs. There was increased relative abundance of genus Clostridium_XlVa as well as genus Blautia, more abundance of Ruminococcus2 in patients with lower levels of T, B, CD4+T, and Tregs. In addition, the relative abundances of Pelagibacterium, Oxalobacter, ClostridiumXlVb, and ClostridiumXVIII were correlated with cytokines. Gut microbiome of RA patients was clearly different from that of HCs. Abnormal bacteria communities are associated with the altered levels of lymphocyte subpopulation and cytokines, which might be one of the pathogenesis of RA.

Maternal Probiotic or Synbiotic Supplementation Modulates Jejunal and Colonic Antioxidant Capacity, Mitochondrial Function, and Microbial Abundance in Bama Mini-piglets.

The present study was conducted to investigate the effects of maternal probiotic or synbiotic supplementation during gestation and lactation on antioxidant capacity, mitochondrial function, and intestinal microbiota abundance in offspring weaned piglets. A total of 64 pregnant Bama mini-sows were randomly allocated into the control group (basal diet), antibiotic group (basal diet + 50 g/t virginiamycin), probiotic group (basal diet + 200 mL/d probiotics per pig), or synbiotic group (basal diet + 200 mL/d probiotics per pig + 500 g/t xylo-oligosaccharides). On day 30 of post-weaning, eight piglets per group with average body weight were selected for sample collection. The results showed that maternal probiotic supplementation increased the catalase (CAT) activity in plasma and glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities in plasma, jejunum, and colon of piglets while decreased the malondialdehyde (MDA) and H2O2 concentrations in plasma compared with the control group (P < 0.05). Moreover, maternal synbiotic supplementation increased the plasma CAT activity, jejunal glutathione and GSH-Px activities, jejunal and colonic total antioxidant capacity activity, and plasma and colonic SOD activity while decreased the colonic MDA concentration of offspring piglets compared with the control group (P < 0.05). The mRNA levels of antioxidant enzyme-related genes (copper- and zinc-containing superoxide dismutase, nuclear factor erythroid 2-related factor 1, and nuclear factor erythroid 2-related factor 2) and mitochondrial-related genes (adenosine triphosphate synthase alpha subunit, adenosine triphosphate synthase β, and mitochondrial transcription factor A) in the jejunal mucosa were significantly upregulated, while the level of colonic peroxisome proliferator-activated receptor γ coactivator-1α was downregulated by maternal synbiotic supplementation (P < 0.05). Maternal probiotic supplementation increased (P < 0.05) the Bacteroidetes abundance in the jejunum and Bifidobacterium abundance in the jejunum and colon, and synbiotic supplementation increased (P < 0.05) the abundances of Firmicutes, Bacteroidetes, Bifidobacterium, and Lactobacillus in the jejunum of piglets. Furthermore, correlation analysis revealed that intestinal microbiota abundances were significantly correlated with antioxidant enzyme activities and mitochondrial-related indexes. These findings indicated that maternal probiotic or synbiotic supplementation might be a promising strategy to improve the antioxidant capacity and mitochondrial function of offspring weaned piglets by altering the intestinal microbiota.

Glucagon-like peptide (GLP) -2 improved colonizing bacteria and reduced severity of ulcerative colitis by enhancing the diversity and abundance of intestinal mucosa

ABSTRACT The global incidence of ulcerative colitis (UC) continues to increase while it’s clinical cure rate remains low. Intestinal mucosal ulcers have segmental distribution and variable severity. Intestinal bacteria are closely related to intestinal immunity and metabolism; however, the relationship between intestinal microbiome profile and the occurrence of UC, as well as the contribution of glucose metabolism, are not well understood. This was investigated in the present study using mucosal biopsies from patients with UC and healthy control subjects. We performed high throughput 16S rRNA gene sequencing to estimate microbiota composition and abundance as well as their association with clinical indices such as lesion severity. The results showed that the diversity and abundance of intestinal microbiota were significantly lower in patients with UC than in healthy subjects; however, these were unrelated to ulcer severity. Serum glucagon-like peptide 2 (GLP-2) level was associated with reduced microbiota diversity and abundance in UC. These results indicate that colonization by specific microbiota is not the main determinant of pathologic status in UC. Additionally, therapeutic strategies that increase GLP-2 levels in intestinal mucosa may be effective in the treatment of UC.

The secondary bacterial infection caused by WSSV outbreaks impacts shrimp Marsupenaeus japonicus’ growth as well as its intestinal microbiota’s composition and function

Intestinal microbiota homeostasis is a complex ecosystem and is essential for promoting aquatic animals’ growth. Invading pathogens can cause dynamical composition and structure change in the hosts’ microbiota due to this affecting their functions. WSSV is one of the most common and dangerous shrimp pathogens, which leads to white spot disease with too high mortality. A few studies on shrimp intestinal microbiota mainly focused on the changes during acute infection stage. Marsupenaeus japonicus is one of the most cultured shrimp with a decent ability to cope with environmental changes. In the current research, using M. japonicus as a model, we compared the differences of intestinal microbiota between healthy shrimp and the shrimp that survived through the WSSV outbreak. Our study showed that compared to the healthy M. japonicus, the WSSV outbreak disrupted intestinal microbiota structure in the survived shrimp: There was less potential beneficial bacteria and more harmful bacteria. Furthermore, the diversity and total abundance of intestinal microbiota in WSSV-survived shrimp increased significantly. On top of that, a metagenomic analysis by PICRUSt suggested that the changed intestinal microbiota could help the host to combat the secondary bacterial infections caused by WSSV outbreaks by regulating cell growth and death, reducing cell motility, improving energy metabolism, and increasing intestinal enzyme activities regardless the smaller sizes of WSSV-survived shrimp. This could be a result of excessive energy consumption and reduced nutrient-absorbing intestinal microbiota. Our study indicated that shrimp intestinal microbiota plays a fundamental role in combating against secondary infections and regulating the hosts’ growth post WSSV outbreaks. The eventual goal is to development of more efficient diagnostics and therapeutic strategies.

Probiotic Lactobacillus rhamnosus GG Promotes Mouse Gut Microbiota Diversity and T Cell Differentiation.

Lactic acid bacteria (LAB) are the primary genera of the intestinal flora and have many probiotic functions. In the present study, Lactobacillus rhamnosus GG (LGG) ATCC 53103 was used to treat BALB/c mice. After LGG intervention, both low and high LGG doses were shown to improve the observed OTU, Chao1, ACE, and Shannon indices, while the Simpson index decreased, demonstrating that LGG can promote intestinal microbiota abundance and diversity. Furthermore, LGG treatment increased the abundances of intestinal Firmicutes, Bacteroides and Actinomycetes while reducing that of Proteobacteria. In addition to its effect on gut the microbiota, LGG could also regulate the host immune system. In the present study, we showed that LGG could affect the percentage of CD3+ T lymphocytes in the spleens (SPLs), mesenteric lymph nodes (MLNs), Peyer’s patches (PPs) and lamina propria lymphocytes (LPLs) of mice, including total CD3+ T, CD3+CD4+ T, and CD3+CD8+ T lymphocytes. Furthermore, LGG could effectively increase the expression of Th1-type cytokines (IFN-γ) and Th2 cytokines (IL-4) in CD4+ T cells, indicating that the proportion of Th1 and Th2 cells in mice with LGG treatment was in a high equilibrium state compared to the control group. In addition, the IFN-γ/IL-4 ratio was greater than 1 in mice with LGG intervention, suggesting that LGG tends to mediate the Th1 immune response. The results of the present study also showed that LGG upregulated the expression of IL-17 in CD4+ T cells and regulated the percentage of CD4+CD25+Foxp3+ Treg cells in various secondary immunological organs, indicating that LGG may promote the balance of Th-17 and Treg cells.

Fecal and Serum Metabolomic Signatures and Microbial Community Profiling of Postmenopausal Osteoporosis Mice Model.

BackgroundMultiple studies have shown that an imbalance in the intestinal microbiota is related to bone metabolism, but the role of the intestinal microbiota in postmenopausal osteoporosis remains to be elucidated. We explored the effect of the intestinal microbiota on osteoporosis.MethodsWe constructed a postmenopausal osteoporosis mouse model, and Micro CT was used to observe changes in bone structure. Then, we identified the abundance of intestinal microbiota by 16S RNA sequencing and found that the ratio of Firmicutes and Bacteroidetes increased significantly. UHPLC-MS analysis was further used to analyze changes in metabolites in feces and serum.ResultsWe identified 53 upregulated and 61 downregulated metabolites in feces and 2 upregulated and 22 downregulated metabolites in serum under OP conditions, and interestedly, one group of bile acids showed significant differences in the OP and control groups. Network analysis also found that these bile acids had a strong relationship with the same family, Eggerthellaceae. Random forest analysis confirmed the effectiveness of the serum and fecal models in distinguishing the OP group from the control group.ConclusionsThese results indicated that changes in the gut microbiota and metabolites in feces and serum were responsible for the occurrence and development of postmenopausal osteoporosis. The gut microbiota is a vital inducer of osteoporosis and could regulate the pathogenesis process through the “microbiota-gut-metabolite-bone” axis, and some components of this axis are potential biomarkers, providing a new entry point for the future study on the pathogenesis of postmenopausal osteoporosis.

Rice-shrimp culture: a better intestinal microbiota, immune enzymatic activities, and muscle relish of crayfish (Procambarus clarkii) in Sichuan Province.

Intestinal microbiota play an important role in the intestinal immunity and nutrient absorption, even muscle nutritional components, and the composition and function were affected by environment. In this study, the intestinal microbiota and immune enzyme, nutritional flavor of muscle of crayfish in rice field, and pond cultivation model were compared in summer and autumn. The results of Shannon diversity and Chao 1 index of intestinal microbiota based on 16S sequencing analysis showed that the diversity and abundance in autumn were higher than in summer. And the diversity and abundance of intestinal microbiota of different model in the same season were different. Four dominant phyla (relative abundance > 5% at least in one sample) of the intestinal microbiota were Bacteroidetes, Firmicutes, Proteobacteria, and Tenericutes. From summer to autumn, the intestinal immune enzyme activity of crayfish in both models showed a decreasing trend. In summer, the activity of catalase and alkaline phosphatase of crayfish cultured in the pond was significantly higher than that in rice field (P < 0.05). In autumn, the activity of catalase and lysozyme of crayfish cultured in rice field was significantly higher than that in pond (P < 0.05). The contents of umami and sweetish amino acids of muscle were higher in rice field than in pond, and the percentage of glutamic acid and alanine was significantly higher in rice field than in pond (P < 0.05). Thus, rice field model can make crayfish a more stable intestinal environment and a better intestinal immune enzyme activity and muscular flavor. Key points • The intestinal microbiota of crayfish in rice field had tended to stabilize from summer to autumn. • The crayfish had better nutrient absorption and stronger immune abilities in the rice field. • The crayfish cultured in rice field had higher overall umami concentration than in pond.

Enteritis in hybrid sturgeon (Acipenser schrenckii♂ × Acipenser baeri♀) caused by intestinal microbiota disorder

Intestinal microbiota is crucial for the regulation of the immune system and feeding habits in aquatic animals, as well as preventing the invasion of pathogenic microorganisms. However, disorders of the intestinal microbiota can lead to numerous, possibly life-threatening diseases. In the present study, we reported a disease occurring in cultured hybrid sturgeons (Acipenser schrenckii♂×Acipenser baeri♀) in the Sichuan province, Southwest China. The diseased fish did not exhibit obvious skin lesions, with observed symptoms including intestine dilatation with large amounts of gas and a transparent intestinal wall. Pathological examinations, microbiological tests, and the high-throughput sequencing of intestinal microbiota were performed to investigate the cause of death of diseased sturgeons. Results demonstrated that no bacteria were isolated from the liver, spleen and kidney, and no obvious changes were observed in tissues, with the exception of the intestine. The intestines demonstrated marked necrotic enteritis with lumen dilatation and a large number of bacteria attached to the base of the intestinal villus. Furthermore, observations from an electron microscope revealed the invasion by bacteria of the striated border. Results from the 16 s rRNA high-throughput sequencing of intestinal microbiota indicate variations in the relative abundance and distribution uniformity of the intestinal microbiota in the diseased group. More specifically, the intestinal microbiota abundance in the diseased group was higher in Clostridium, Cetobacterium, and Lactococcus, and lower in Mycoplasma at the genus level compared to the healthy group. Our observations suggest that the death of the hybrid sturgeons was caused by intestinal enteritis, which itself was a result of the intestinal microbiota disorder. To our knowledge, this is the first study to reveal hybrid sturgeon death via enteritis caused by an intestinal microbiota disorder.

Individual and combined toxicogenetic effects of microplastics and heavy metals (Cd, Pb, and Zn) perturb gut microbiota homeostasis and gonadal development in marine medaka (Oryzias melastigma)

Currently, microplastics (MPs) attracted increased attention for their ubiquity and toxic properties. In this study, marine medaka was used to explore the individual and combined toxicity of heavy metals (HMs) and MPs on intestinal bacteria and gonadal development. After exposure to environmentally relevant concentrations of MPs and HMs, significant alterations of intestinal microbiota were found. The MPs treatment reduced the diversity and abundance of intestinal microbiota, while the HMs and MPs-HMs treatments increased them, which were confirmed by the abundance changes of Proteobacteria. According to the KEGG analysis, the metabolism and environmental information processing (EIP) pathways in the microbial community were significantly affected. This study showed that the MPs-HMs treatment caused a higher pollution load on the gut of the marine medaka, and triggered more significant changes of specific bacterial species and gut function in the males. However, during the gonadal development, HMs and MPs-HMs treatments resulted in empty follicles (EF) and follicular atresia (FA), and altered the gene expression levels related to hypothalamic-pituitary-gonadal (HPG) axis. In short, this study demonstrated that the reproductive disturbance was mainly due to HMs, but the combination of MPs and HMs did not strengthen the risk to the gonad development of the marine medaka.

Two Bariatric Surgical Procedures Differentially Alter the Intestinal Microbiota in Obesity Patients.

To explore the intestinal microbiota composition affected by the two most widely used procedures of bariatric surgery, laparoscopic sleeve gastrectomy (LSG) and laparoscopic roux-en-Y gastric bypass (LRYGB), in Chinese obesity patients. Stool samples were collected from the obese patients before (n = 87) and with follow-up after the surgery (n = 53). After DNA extraction, 16S rDNA (V3 + V4 regions) sequencing was completed on Illumina HiSeq 2500 sequencing platform. The samples were analyzed base on four groups, pre-LSG (n = 54), pre-LRYGB (n = 33), post-LSG (n = 33), and post-LRYGB (n = 20). The linear mixed models were used to analyze the alteration of intestinal microbiota before and after the surgeries of LSG or LRYGB. Student's t test and χ2 test were used for analysis of independent groups; Metastats analysis was used to compare the relative abundance of bacteria, and Pearson correlation and Spearman correlation analysis were used to test the correlation between indicated groups. 87 patients were included and 53 (60.92%) of them completed the follow-up (9.60 ± 3.92months). Body mass index (BMI) decreased from 37.84 ± 6.16kg/m2 to 26.22 ± 4.33kg/m2 after LSG and from 45.75 ± 14.26kg/m2 to 33.15 ± 10.99kg/m2 after LRYGB. The relative abundance of 5 phyla and 42 genera were altered after the surgery in the cohort. Although no alteration of Firmicutes was observed at phylum level, 54.76% of the altered genera belong to phylum Firmicutes. Both LSG and LRYGB procedures increased the richness and evenness of intestinal microbiota in obese patients after the surgery. Particularly, 33 genera altered after LSG and 19 genera altered after LRYGB, in which 11 genera were common alterations in both procedures. Both LSG and LRYGB altered the composition of intestinal microbiota in Chinese obesity patients, and particularly increased the richness and evenness of microbiota. Genera belonging to phylum Firmicutes were the most altered bacteria by bariatric surgery. The procedure of LSG resulted in much more pronounced alteration of the intestinal microbiota abundance than that observed in LRYGB. While different genera were altered after LSG and LRYGB procedures, 10 genera were the common altered genera in both procedures. Bacteria altered after LSG and LRYGB were functionally associated with BMI, and with relieving of the metabolic syndromes.

Inclusion of the direct-fed microbial Clostridium butyricum in diets for weanling pigs increases growth performance and tends to increase villus height and crypt depth, but does not change intestinal microbial abundance.

An experiment was conducted to test the hypothesis that inclusion of the direct fed microbial Clostridium butyricum in diets for weanling pigs will improve growth performance, systemic immune function, microbiota composition, and gut morphology in weaned pigs. A total of 275 newly weaned pigs (20 ± 2 d of age) with an average initial BW of 6.4 ± 0.8 kg were allotted to a randomized complete block design with 11 pens per treatment. Diets included a positive control diet containing Carbadox, a negative control diet without Carbadox, and three treatment diets in which 1,250 × 108 cfu/kg, 2,500 × 108 cfu/kg, or 3,500 × 108 cfu/kg of C. butyricum was added to the negative control diet. A two-phase feeding program was used (phase 1, 14 d; phase 2, 21 d). At the conclusion of the experiment (day 35), a blood sample was collected from one pig per pen (11 pigs per treatment) and this pig was then euthanized and digesta and tissues samples were collected. Results indicated that for the overall phase, pigs fed the positive control diet had greater (P < 0.05) ADG and ADFI and tended (P = 0.064) to have greater final BW than pigs fed the negative control diet. The ADG and G:F increased and then decreased as increasing doses of C. butyricum were included in the diet (quadratic, P < 0.05). The concentration of tumor necrosis factor-α was less (P < 0.05) in pigs fed the positive control diet compared with pigs fed the negative control diet or diets containing C. butyricum. Crypt depth tended (P = 0.08) to be less in pigs fed the negative control diet compared with pigs fed the positive control diet and villus height tended to increase as the doses of C. butyricum increased in the diets (quadratic, P = 0.08). Villus height also tended (P = 0.084) to be greater in pigs fed diets containing C. butyricum compared with pigs fed the positive control diet. Crypt depth increased as the dose of C. butyricum increased (quadratic, P < 0.05) and villus width at the bottom tended to increase (linear, P = 0.072) as the dose of C. butyricum increased in the diet. Alpha and beta diversity indices of ileal and colonic microbiota were not affected by diet. In conclusion, addition of 1,250 × 108 cfu/kg of C. butyricum, but not greater levels, to diets fed to weanling pigs increased growth performance and tended to increase villus height and crypt depth, but changes in the abundance of intestinal microbiota were not observed.

Changes of intestinal bacterial microbiota in coronary heart disease complicated with nonalcoholic fatty liver disease

BackgroundPrevious study reported that patients who suffered coronary heart disease (CHD) complicated with non-alcoholic fatty liver disease (NAFLD) had worse cardiac function and clinical outcomes than patients with CHD only. Notably, the mechanism is still unclear. This study aimed to investigate the changes and roles of intestinal bacterial microbiota in CHD-NAFLD patients.Methods and resultsPeople were recruited and divided into three groups, including CHD patients (without NAFLD), CHD-NAFLD patients and healthy controls (HCs). Each group contained 24 people. Fecal samples and clinical information were carefully collected. The Illumina sequencing of 16S rRNA was applied to profile the overall structure of the fecal bacterial microbiota and the characteristics of the bacterial microbiota based on the Operational Taxonomic Units. In clinical information, the CHD-NAFLD patients showed an increase in BMI, uric acid and triglyceride. There was a significant reduction in the abundance of Parabacteroides and Collinsella in overall CHD patients (including CHD-NAFLD and CHD patients). The intestinal bacterial microbiota in CHD-NAFLD patients showed an increase in the abundance of Copococcus and Veillonella, and a reduction in the abundance of Parabacteroides, Bacteroides fragilis, Ruminococcus gnavus, Bacteroides dorei, and Bifidobacterium longum subsp infantis. Among them, the abundance of Ruminococcus gnavus and Bacteroides dorei was significantly lower than that in CHD patients. Additionally, BMI positively correlated with the abundance of Copococcus and negatively correlated with the abundance of Bifidobacterium longum subsp infantis. The abundance of Veillonella positively correlated with AST. The abundance of Bacteroides dorei negatively correlated with ALT and AST. It indicates that the abundance of intestinal microbiota was related to the changes in clinical indexes.ConclusionsChanges of intestinal bacterial microbiota in CHD-NAFLD patients may be important factors affecting the degree of metabolic disorder, which may be one of the important reasons for the worse clinical outcome and disease progression in CHD-NAFLD patients than in CHD patients.

Bacupari (Garcinia brasiliensis) extract modulates intestinal microbiota and reduces oxidative stress and inflammation in obese rats.

The objective of this study was to evaluate the effects of an ethanolic extract of the bark of bacupari (Garcinia brasiliensis - EEB) on the abundance of intestinal microbiota, concentration of short-chain fatty acids (SCFAs), oxidative stress, and inflammation in obese rats fed a high-fat diet (HFD). Male Wistar rats were divided into three groups: an HFD-fed obese control group, a group fed HFD plus EEB (BHFD) at a dose of 300 mg per animal per day (42 mg 7-epiclusianone and 10.76 mg morelloflavone), and a lean control group fed an AIN-93 M diet for 8 weeks. EEB decreased (p < 0.05) the abundance of organisms belonging to the phyla Firmicutes and Proteobacteria, and increased (p < 0.05) the concentration of propionic acid. Liver concentrations of malondialdehyde, nitric oxide, resistin, and p65 nuclear factor-kappa B p65(NF-κB) decreased (p < 0.05), while the expression of heat shock protein (HSP)72 and catalase increased (p < 0.05) with the consumption of EEB. Moreover, computational molecular modeling studies involving molecular docking between the main constituents of EEB, 7-epiclusianone and morelloflavone, and NF-κB suggested its inhibitory activity, thus corroborating the experimental results. The consumption of EEB may therefore be a promising strategy for the beneficial dietary modulation of the intestinal ecosystem, thereby countering oxidative stress and inflammation in obese rats. This activity is attributable to the presence of bioactive compounds that act individually or synergistically in the scavenging of free radicals or in the inflammatory process.

Structural characteristics and succession of intestinal microbiota for Paralichthys olivaceus during the early life stage

The research of intestinal microflora structures for Paralichthys olivaceus larvae and juveniles will help us to master the ontogeny and developmental colonization of microflora during the larval rearing stage. In this study, we sequenced the total bacterial genomic DNA in larval and juvenile guts with an Illumina MiSeq PE300 system, and analysed the structural characteristics of these microbiota, feed and rearing water in live and formulated feeding periods. The structure of gut microbiota was gradually similar to those in wild P. olivaceus at the phylum level and the newly hatched ones with the growth, according to the distribution and abundance of intestinal microbiota. And the colonized rule of main microbial species in guts was decreased initially and then increased during the larvae and juveniles stage. Meantime, the core microflora of this study were obtained through the analysis of shared and dominant species, which included Bacteroides, Bacillus, Enterococcus, Lactobacillus, Lactococcus, Escherichia_Shigella, Acinetobacter, Pseudomonas, Vibrio, Nitrosomonas, and Glaciecola. The correlation analysis of microbiota between intestines and environmental factors suggested that microflora in feed and water could affect the distribution of larval and juvenile gut microbiota. Moreover, many species of Acinetobacter, Pseudomonas and Vibrio are treated as important potential pathogens in aquaculture. These all pointed out the microbial quality of feed and rearing water should be strictly controlled in fish breeding and farming, and supply theoretical bases for screening the native probiotics to artificially regulate the gut microbiota.

A Microbiota-Derived Bacteriocin Targets the Host to Confer Diarrhea Resistance in Early-Weaned Piglets

Alternatives to antibiotics for preventing diarrhea in early-weaned farm animals are sorely needed. CM piglets (a native Chinese breed) are more resistant to early-weaning stress-induced diarrhea than the commercial crossbred LY piglets. Transferring fecal microbiota, but not saline, from healthy CM into LY piglets by oral administration prior to early weaning conferred diarrhea resistance. By comparing the relative abundance of intestinal microbiota in saline and microbiota transferred LY piglets, we identified and validated Lactobacillus gasseri LA39 and Lactobacillus frumenti as two bacterial species that mediate diarrhea resistance. Diarrhea resistance depended on the bacterial secretory circular peptide gassericin A, a bacteriocin. The binding of gassericin A to Keratin 19 (KRT19) on the plasma membrane of intestinal epithelial cells was essential for enhancement of fluid absorption and decreased secretion. These findings suggest the use of L. gasseri LA39 and L. frumenti as antibiotic alternatives for preventing diarrhea in mammals.

Effects of prebiotics on immunologic indicators and intestinal microbiota structure in perioperative colorectal cancer patients.

The aim of the present study was to investigate the effects of prebiotics (containing fructooligosaccharides, xylooligosaccharides, polydextrose, and resistant dextrin) intake on immune function and intestinal microbiota structure in perioperative patients with colorectal cancer (CRC). A randomized, double-blind, no-treatment parallel control clinical trial involving 140 perioperative patients (90 men and 50 women, aged 40-75 y) with CRC was performed. Patients were randomly divided into two groups: an intervention group (prebiotic group, n = 70) that received prebiotic supplementation of 30 g/d for 7 d, and a control group (non-prebiotic group, n = 70) that received no prebiotic supplementation. The nutritional and immunologic indices were evaluated for both groups before and after operation and analyzed against baseline values. Moreover, fecal samples were collected from 40 patients randomly chosen from the two groups to study intestinal microbiota, which was analyzed by sequencing the V3-V4 region of 16S ribosomal DNA using the Illumina (San Diego, CA) MiSeq (PE 2 × 300 bp) platform. Oral intake of prebiotics produced significant effects on immunologic indices in both the preoperative and postoperative periods, but the patterns of effects were different. In the preoperative period, prebiotics increased serum levels of immunoglobulin G (IgG; P = 0.02), IgM (P = 0.00), and transferrin (P = 0.027; all P < 0.05). In the postoperative period, enhanced levels of IgG (P = 0.003), IgA (P = 0.007), suppressor/cytotoxic T cells (CD3+CD8+; P = 0.043), and total B lymphocytes (CD19+; P = 0.012) were identified in the prebiotic group (all P < 0.05). The differences in the intestinal microbiota at the phylum level were not statistically significant between the intervention and control groups (P > 0.05). At the genus level, prebiotics increased the abundance of Bifidobacterium (P = 0.017) and Enterococcus (P = 0.02; both P < 0.05) but decreased the abundance of Bacteroides (P = 0.04) in the preoperative period (all P < 0.05). In the postoperative period, the abundance of Bacteroides (P = 0.04) was decreased, but the abundance of Enterococcus (P = 0.00), Bacillus (P = 0.01), Lactococcus (P = 0.00), and Streptococcus (P = 0.037) increased in the non-prebiotic group (all P < 0.05); however, no significant change was identified in the abundance of Enterococcus (P = 0.56), Lactococcus (P = 0.07), and Streptococcus (P = 0.56) as a result of prebiotic intervention in this period (all P > 0.05). The abundance of Escherichia-Shigella was increased after prebiotic intake in the postoperative period (P = 0.014, P < 0.05). There was a notable trend of decline in the abundance of intestinal microbiota from preoperative to postoperative in the non-prebiotic group. Prebiotic intake is recommended to improve serum immunologic indicators in patients with CRC 7 d before operation. Prebiotics improved the abundance of four commensal microbiota containing opportunistic pathogens in patients with CRC. Surgical stress decreased the abundance of most intestinal microbiota in the intestinal tract but increased the abundance of some opportunistic pathogens and commensal microbiota. Bacteroides is a relevant bacterial species for further research on the mechanism of prebiotics.

Effects of shenling baizhu powder herbal formula on intestinal microbiota in high-fat diet-induced NAFLD rats

BackgroundWorldwide, non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease closely associated with obesity, diabetes and other metabolic diseases. Shenling Baizhu powder (SLBZP), a formulation of a variety of natural medicinal plants, has hepatoprotective properties and clinical efficacy in treating non-infectious intestinal disease. SLBZP has improved NAFLD symptoms; however, its mechanism of action is unknown. MethodsWe established an NAFLD model in rats given a high-fat diet (HFD), administered different interventions and measured serum biochemical indices and inflammatory factors. Liver tissues were stained with hematoxylin and eosin (HE) and oil red O, and colon tissues were analyzed by immunohistochemistry. The expression profiles of liver TLR4 pathway related protein was confirmed by western blotting. Changes in intestinal microbiota composition were analyzed using a 16S rDNA sequencing technique. ResultsOf note, SLBZP effectively reduced body weight in HFD-fed rats (p < 0.05). Serum biochemical analysis indicated that SLBZP decreased the serum level of total cholesterol (TC) and improved liver function. Additionally, SLBZP decreased the serum level of endotoxin, tumor necrosis factor α (TNF-α), interleukin-1β (IL-β) (p < 0.05), and decreased the expression of TLR4 pathway related protein. Pathological examination showed that SLBZP alleviates hepatic steatosis and repairs colon mucosa. Microbiome analysis revealed that SLBZP improved the abundance of intestinal microbiota. In taxonomy-based analysis, compared with control rats, SLBZP-treated rats showed obvious changes in intestinal microbiota composition. Moreover, SLBZP increased the relative abundance of short-chain fatty acid (SCFA)-producing bacteria, including Bifidobacterium and Anaerostipes. ConclusionTaken together, these results suggest that the effects of SLBZP against NAFLD may be related to the increased abundance of beneficial gut microbiota and decreased levels of LPS in the portal vein.