Diversity Of Intestinal Bacteria Research Articles

Effects of Formulated Pellet Feed or Live Fish Food on the Intestinal and Aquaculture Water Microbial Communities in Goldfish, Carassius auratus

This study investigates the impact of different diets on fish growth and bacterial community structure present in the intestine of goldfish (Carassius auratus) and their aquaculture water under recirculating water conditions. We assumed that different types of diet would form different intestinal microbiota that may affect host growth. Using Illumina MiSeq high-throughput sequencing, we analyzed bacterial communities in goldfish fed with formulated pellet feed, Tubifex worms (Limnodrilus hoffmeisteri), and an alternating diet of both. Over a 14-day feeding trial, no significant differences in juvenile goldfish growth were observed between groups. After 7 days, diet changes significantly influenced the abundance and diversity of intestinal bacteria, with the alternating diet notably enhancing bacterial diversity in both the intestines and water. However, these differences in bacterial diversity decreased by day 14. The results indicate that diet type affects microbial community diversity in the intestines and water of goldfish, and that goldfish intestines maintain a stable core bacterial community structure. This highlights the potential for optimizing diet types to enhance microbial health and stability in aquaculture systems and, in addition, provides an important scientific basis for alternative diets in goldfish aquaculture in the industry.

Gut Microbial Adaptation to Varied Altitudes and Temperatures in Tibetan Plateau Yaks.

The yak (Bos grunniens) exhibits exceptional regional adaptability, enabling it to thrive in the distinctive ecological niches of the Qinghai-Tibet Plateau. Its survival relies on the intricate balance of its intestinal microbiome, essential for adapting to harsh environmental conditions. Despite the documented significance of bacteria and fungi in maintaining intestinal homeostasis and supporting immune functions, there is still a substantial gap in understanding how the composition and functionality of yak gut microbiota vary along altitude-temperature gradients. This study aims to fill this gap by employing 16S rRNA and ITS amplicon sequencing techniques to analyze and compare the intestinal microbiome of yaks residing at different elevations and exposed to varying temperatures. The findings demonstrate subtle variations in the diversity of intestinal bacteria and fungi, accompanied by significant changes in taxonomic composition across various altitudes and temperature gradients. Notably, Firmicutes, Actinobacteriota, and Bacteroidota emerged as the dominant phyla across all groups, with Actinobacteriota exhibiting the highest proportion (35.77%) in the LZF group. Functional prediction analysis revealed significant associations between the LZF group and metabolic pathways related to amino acid metabolism and biosynthesis. This suggests a potential role for actinomycetes in enhancing nutrient absorption and metabolism in yaks. Furthermore, our findings suggest that the microbiota of yaks may enhance energy metabolism and catabolism by modulating the Firmicutes-to-Bacteroidota ratio, potentially mitigating the effects of temperature variations. Variations in gut bacterial and fungal communities among three distinct groups were analyzed using metagenomic techniques. Our findings indicate that microbial genera exhibiting significant increases in yaks at lower altitudes are largely beneficial. To sum up, our research investigated the changes in gut bacterial and fungal populations of yaks residing across diverse altitude and temperature ranges. Moreover, these results enhance comprehension of gut microbial makeup and variability, offering perspectives on the environmental resilience of dry lot feeding yaks from a microbial angle.

Relationship between gut microbiota and its metabolite dysregulation and postoperative cognitive dysfunction in elderly male C57BL/6J mice after laparotomy exploration

Objective: To explore the relationship between gut microbiota and its metabolite dysregulation and postoperative cognitive dysfunction in elderly male C57BL/6J mice after laparotomy exploration. Methods: A total of 48 specific pathogen-free (SPF) male C57BL/6J mice, aged 16-17 months, were divided into two groups by random number table method: control group (n=24) and operation group (n=24). Mice in the operation group were induced with 1.4% isoflurane for 15 minutes, followed by a 10 minutes exploratory laparotomy anesthetized with 1.4% isoflurane and 100% oxygen, and anesthesia continued for 2 hours after surgery. Mice in control group were put in 100% oxygen for 2 hours. Feces and venous blood samples of both groups were collected 48 hours after surgery. Changes in the abundance and diversity of intestinal bacteria in the feces were detected by 16S rDNA gene sequencing. Functional changes of fecal metabolic profiles were detected by liquid chromatography tandem mass spectrometry (LC/MS) metabolomics and differential metabolite functions were analyzed. The serum level of interleukin (IL)-6, IL-1β and tumor necrosis factor-α (TNF-α) were detected by Enzyme-linked immunosorbent assay (ELISA). The cognitive function of the mice was detected by Morris water maze test 3 days after operation. Results: The postoperative escape latency of mice in control group and operation group was (22.0±4.9) and (35.0±5.1) s, and the target quadrant residence time was (26.0±3.7) and (16.0±2.9) s, respectively. Compared with the control group, the postoperative escape latency of mice in the operation group was prolonged (P=0.035), and the residence time in the target quadrant was reduced (P=0.006). The difference of intestinal flora between the two groups was comparable. The expression levels of Escherichia coli, shigella and clostridium in the operation group were up-regulated, while the expression levels of rumen bacteria and butyricobacteria were down-regulated. Fecal metabolic profiles of mice in control group and operation group were obtained by LC/MS, and 14 and 21 different metabolites were screened in positive and negative ion modes, respectively. The different metabolites in positive ion mode were glutamic acid, 2-indoleic acid, kynuuric acid and glyceraldehyde. The negative ion pattern differential metabolites are methionine, aspartic acid, L-threonine, tyrosyl-threonine and 5-hydroxyindole-3-acetic acid. The identified differential metabolite pathways are mainly involved in amino acid, fatty acid and tryptophan metabolism and nucleotide synthesis. There were no significant differences in serum levels of IL-1β, IL-6 and TNF-α between the two groups (all P>0.05). Conclusion: The dysregulated changes of gut microbiota and its metabolites are correlated with the occurrence of postoperative cognitive dysfunction in elderly male C57BL/6J mice. Anesthesia and surgery alter the structure of mice intestinal bacteria on the level of abundance, and change the metabolic balance and feces metabolomic phenotype.

Fucosylated chondroitin sulfate from sea cucumber Stichopus chloronotus alleviate the intestinal barrier injury and oxidative stress damage in vitro and in vivo

This study aimed to investigate the alleviative effects of fucosylated chondroitin sulfate from sea cucumber Stichopus chloronotus (fCSSc) on the intestinal barrier injury and oxidative stress damage in vitro and in vivo. The results showed that fCS-Sc protected the intestinal barrier and improved the antioxidant function in H2O2 damaged Caco-2 cells via up-regulating the tight junction proteins and activating Keap1-Nrf2-ARE antioxidant pathway. Furthermore, administration fCS-Sc could ameliorate the weight loss and spleen index decrease in Cyclophosphamide (Cy) treated mice, improve the expressions of ZO-1, Claudin-1, Nrf2, SOD, and NQO-1 in Cy damaged colon tissue, showing significant protective effects against intestinal barrier damage and oxidative stress in vivo. fCS-Sc intervention also alleviated the gut microbiota disorder though increasing the richness and diversity of intestinal bacteria, regulating the structural composition of gut microbiota. fCS-Sc promoted the relative abundance of beneficial microbiota and inhibited the growth of harmful bacteria. This study provided a theoretical basis for the application of fCS-Sc as a prebiotic in chemotherapy.

Does intestinal bacteria diversity drive multi-dimensional sheep (Ovis aries) health?

Although previous research has shown that several health disorders affect gastrointestinal microbiome flora, there is no consensus on the relationship between gastrointestinal microorganism diversity and ruminant health. Therefore, we revealed how intestinal bacterial flora diversity affects the overall health of sheep (Ovis aries) from multiple perspectives. We gathered total 17 data on behaviour (time allocation and action intensity on a 3-dimensional axis), nutrition (blood parameters, body condition), physical attributes, and resistance to parasitic infection (blood parameters, blood cell components, and eggs per gram [EPG] counts) from 20 sheep—both housed and grazing—at a Japanese farm. We defined an abnormal individual as one out of the normal range for blood parameters and the confidence interval among the 20 sheep in each behaviour. The species composition and diversity of intestinal bacteria in each sheep were determined by 1) extracting DNA from collected faeces, 2) identifying the species based on genetic approaches, and 3) calculating the diversity index using species composition at the phylum and genus levels. The calculated diversity indices were compared with those of the sheep group classified by the sum of abnormal measurements. The Shannon and Simpson diversity indices at the phylum and genus levels were 1.69 and 4.47 and 0.55 and 0.93, respectively. The sum of abnormal health measurements in each sheep ranged from 4 to 7, including mainly blood biological properties. Healthy sheep with lower total numbers of abnormal measurements tended to have higher Simpson lambda (p = 0.095) and Shannon–Weiner H′ indices (p = 0.085) of intestinal microbiota at the genus level. Therefore, it can be considered that the higher the diversity of intestinal microbiota at the genus level, the more functional species (working in the intestine in absorption, ingestion, immunity, and physiologically) would coexist, playing a role in overall ruminant health.

The Microbiome-Thyroid Link: A Review of the Role of the Gut Microbiota in Thyroid Function and Disease

The gut microbiota has emerged as a potential regulator of thyroid homeostasis and disease. Recent studies suggest that the composition and diversity of intestinal bacteria can impact thyroid stimulating hormone levels, thyroid hormone synthesis & metabolism and the risk of thyroid conditions like hypothyroidism and autoimmune thyroiditis. However, the mechanisms through which the gut microbiota influences the thyroid remain poorly understood. This review aims to summarize the current evidence on the role of the gut-thyroid microbiome axis in thyroid physiology and pathophysiology. Studies investigating the association of gut dysbiosis with altered thyroid function and disorders like Hashimoto’s thyroiditis were discussed. Potential mechanisms through which gut bacteria may influence thyroid hormone levels and autoimmunity, such as interference with autoantigen presentation, induction of inflammation, and production of metabolites were evaluated. The impact of dietary and probiotic interventions targeting the gut microbiota for managing thyroid disease is assessed. Future research directions focusing on delineating key bacteria influencing thyroid health, characterizing longitudinal microbiota changes in thyroid conditions, and identifying novel microbiota-based therapies are proposed. A deeper understanding of the gut-thyroid axis may lead to microbiota-targeted strategies for managing thyroid disorders.

Shimanami Leaf Intake Affects Bowel Movement and Intestinal Microbiota in Mice.

The Shimanami Leaf®, produced at Innoshima Island in Onomichi City, Hiroshima Prefecture, Japan, is a leafy vegetable that does not require pesticide use and has a high nutritional value. Although the leaf has abundant dietary fiber and other nutrients, reports on its biological regulatory functions are lacking. Therefore, this study aimed to elucidate the effects of Shimanami leaf intake on bowel movement and gut microbiota in mice. We examined the effects of Shimanami leaves on fecal weight, fecal water content, and intestinal microbiota composition. On day 10 of administration, the Shimanami leaf-treated group exhibited significantly higher fecal weight and water content than the control group. Next-generation sequencing analysis revealed that the ingestion of Shimanami leaf increased the abundances and diversity of intestinal bacteria, including members from Lactococcus, Streptococcus, and Muribaculaceae. Our findings suggest that Shimanami leaf supplementation improves bowel movement and promotes defecation.

Aluminum, Arsenic, Beryllium, Cadmium, Chromium, Cobalt, Copper, Iron, Lead, Mercury, Molybdenum, Nickel, Platinum, Thallium, Titanium, Vanadium, and Zinc: Molecular Aspects in Experimental Liver Injury.

Experimental liver injury with hepatocelluar necrosis and abnormal liver tests is caused by exposure to heavy metals (HMs) like aluminum, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, mercury, molybdenum, nickel, platinum, thallium, titanium, vanadium, and zinc. As pollutants, HMs disturb the ecosystem, and as these substances are toxic, they may affect the health of humans and animals. HMs are not biodegradable and may be deposited preferentially in the liver. The use of animal models can help identify molecular and mechanistic steps leading to the injury. HMs commonly initiate hepatocellular overproduction of ROS (reactive oxygen species) due to oxidative stress, resulting in covalent binding of radicals to macromolecular proteins or lipids existing in membranes of subcellular organelles. Liver injury is facilitated by iron via the Fenton reaction, providing ROS, and is triggered if protective antioxidant systems are exhausted. Ferroptosis syn pyroptosis was recently introduced as mechanistic concept in explanations of nickel (Ni) liver injury. NiCl2 causes increased iron deposition in the liver, upregulation of cyclooxygenase 2 (COX-2) protein and mRNA expression levels, downregulation of glutathione eroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), nuclear receptor coactivator 4 (NCOA4) protein, and mRNA expression levels. Nickel may cause hepatic injury through mitochondrial damage and ferroptosis, defined as mechanism of iron-dependent cell death, similar to glutamate-induced excitotoxicity but likely distinct from apoptosis, necrosis, and autophagy. Under discussion were additional mechanistic concepts of hepatocellular uptake and biliary excretion of mercury in exposed animals. For instance, the organic anion transporter 3 (Oat3) and the multidrug resistance-associated protein 2 (Mrp2) were involved in the hepatic handling of mercury. Mercury treatment modified the expression of Mrp2 and Oat3 as assessed by immunoblotting, partially explaining its impaired biliary excretion. Concomitantly, a decrease in Oat3 abundance in the hepatocyte plasma membranes was observed that limits the hepatic uptake of mercury ions. Most importantly and shown for the first time in liver injury caused by HMs, titanium changed the diversity of gut microbiota and modified their metabolic functions, leading to increased generation of lipopolysaccharides (LPS). As endotoxins, LPS may trigger and perpetuate the liver injury at the level of gut-liver. In sum, mechanistic and molecular steps of experimental liver injury due to HM administration are complex, with ROS as the key promotional compound. However, additional concepts such as iron used in the Fenton reaction, ferroptosis, modification of transporter systems, and endotoxins derived from diversity of intestinal bacteria at the gut-liver level merit further consideration.

Fermented grape seed meal promotes broiler growth and reduces abdominal fat deposition through intestinal microorganisms.

The fermentation of grape seed meal, a non-conventional feed resource, improves its conventional nutritional composition, promotes the growth and development of livestock and fat metabolism by influencing the structure and diversity of intestinal bacteria. In this study, the nutritional components of Fermented grape seed meal (FGSM) and their effects on the growth performance, carcass quality, serum biochemistry, and intestinal bacteria of yellow feather broilers were investigated. A total of 240 male 14-day-old yellow-feathered broilers were randomly selected and divided into four groups, with three replicates of 20 chickens each. Animals were fed diets containing 0% (Group I), 2% (Group II), 4% (Group III), or 6% (Group IV) FGSM until they were 56 days old. The results showed that Acid soluble protein (ASP) and Crude protein (CP) contents increased, Acid detergent fiber (ADF) and Neutral detergent fiber (NDF) contents decreased, and free amino acid content increased in the FGSM group. The non-targeted metabolome identified 29 differential metabolites in FGSM, including organic acids, polyunsaturated fatty acids, and monosaccharides. During the entire trial period, Average daily gain (ADG) increased and Feed conversion ratio (FCR) decreased in response to dietary FGSM supplementation (p < 0.05). TP content in the serum increased and BUN content decreased in groups III and IV (p < 0.05). Simultaneously, the serum TG content in group III and the abdominal fat rate in group IV were significantly reduced (p < 0.05). The results of gut microbiota analysis showed that FGSM could significantly increase the Shannon and Simpson indices of broilers (35 days). Reducing the relative abundance of Bacteroidetes significantly altered cecal microbiota composition by increasing the relative abundance of Firmicutes (p < 0.05). By day 56, butyric acid content increased in the cecal samples from Group III (p < 0.05). In addition, Spearman’s correlation analysis revealed a strong correlation between broiler growth performance, abdominal fat percentage, SCFAs, and gut microbes. In summary, the addition of appropriate levels of FGSM to rations improved broiler growth performance and reduced fat deposition by regulating gut microbes through differential metabolites and affecting the microbiota structure and SCFA content of the gut.

Bacterial diversity in the intestinal mucosa of heart failure rats treated with Sini Decoction

BackgroundSini Decoction (SND), a classic Chinese medicine prescription, has been proved to have a good effect on heart failure (HF), whereas its underlying mechanism is still unclear. In order to explore the therapeutic mechanism of SND, we combined with 16S rRNA gene sequencing to analyze the composition of gut microflora in rats with HF.Material and methodsTwenty Sprague–Dawley (SD) rats were divided into four groups (n = 5): normal group, model group, SND treatment group (SNT group), and metoprolol (Met) treatment group (Meto group). All the rats except the normal group were intraperitoneally injected with doxorubicin (concentration 2 mg/mL, dose 0.15 mL/100 g) once a week to induce HF. After successfully modeling, SND and Met were gavaged to rats, respectively. After the treatment period, blood was collected for hematological analyses, myocardial tissue and colon tissues were collected for Hematoxylin–Eosin (H&E) staining, and mucosal scrapings were collected for Illumina Miseq high-throughput sequencing.ResultsEchocardiographic results suggested that both left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) in Model rats decreased compared with normal rats. The results of H&E staining showed that compared with the model group, the structures of myocardial tissue and colon tissue in the SNT group and Meto group showed a recovery trend. Alpha results showed that the model group had higher species diversity and richness compared with the normal group. After treatment, the richness and diversity of intestinal bacteria in the SNT group were significantly restored, and Met also showed the effect of adjusting bacterial diversity, but its effect on bacterial richness was not ideal. At the Family level, we found that the number of several bacteria associated with HF in the model group increased significantly. Excitingly, SND and Met had shown positive effects in restoring these HF-associated bacteria. Similarly, the results of Linear discriminant analysis (LDA) showed that both SND and Met could reduce the accumulation of bacteria in the model group caused by HF.ConclusionCollectively, SND can improve HF by regulating the intestinal flora. This will provide new ideas for the clinical treatment of patients with HF.

Toxicity of Pb continuous and pulse exposure on intestinal anatomy, bacterial diversity, and metabolites of Pelophylax nigromaculatus in pre-hibernation

Amphibians are often exposed to pulse pollution due to fluctuational inputs of pollutants in water. Traditional ecotoxicology research is mainly performed under constant exposure conditions, which is not consistent with the true environmental pollution. Frogs are sensitive to changes in water pollutants in pre-hibernation. Thus, to understand the toxicity difference to continuous and pulse exposure in environmental concentrations of Pb (100 μg/L), Pelophylax nigromaculatus adults were exposed to short-term treatments (8 days) in pre-hibernation. Individual mortality, intestinal anatomical structure, bacterial diversity, and metabolites were measured in a control group (CON), a Pb continuous treatment group (CEPb) and a Pb pulse treatment group (PEPb). The results showed that PEPb significantly increased individual mortality, compared to the control group and CEPb. PEPb induced pathological changes in the small intestinal tissues, such as mucosal erosion, swollen and distorted villi, large vacuoles, and the proliferation of goblet cells. In addition, PEPb altered the structure and diversity of intestinal bacteria, resulting in an increase in some pathogenic bacteria (e.g. Bacteroides and Ruminococcus) and a decrease in beneficial bacteria (e.g. Cetobacterium and Akkermansia). Both CEPb and PEPb significantly changed intestinal metabolites and metabolic pathways. Moreover, PEPb has a significant effect on the metabolism of amino acids by increasing the content of 5-Aminopentanoic acid, cis-4-Hydroxy-l-proline, Glycocholic acid, l-Alanine, and l-Isoleucine. We concluded that PEPb may lead to intestine impairment of P. nigromaculatus in pre-hibernation by inducing intestinal structural integrity destruction, bacterial imbalance, and metabolic dysfunction, resulting in a significant increase in mortality. The study provides new insights for understanding the intestinal responses of frogs to pulse metal exposure.

Fecal Stream Diversion Changes Intestinal Environment, Modulates Mucosal Barrier, and Attenuates Inflammatory Cells in Crohn's Disease.

The intestinal environment plays important roles in mucosal barrier homeostasis and intestinal inflammation, as clarified in studies using experimental animals but not in humans. We investigated whether environmental changes in the fecal stream cause phenotypic changes in the human mucosal barrier. We obtained human ileal samples after fecal stream diversions in patients with rectal cancer or Crohn's disease. We investigated the bacterial load and diversity in the human defunctioned ileum, defined as the anal side of the ileum relative to the ileostomy. We also examined the epithelium and lamina propria cell phenotypes in the defunctioned ileum. After fecal stream diversion, bacterial loads decreased significantly in the defunctioned ileum. Based on the Chao1, Shannon, and observed species indices, the diversity of mucosa-associated microbiota was lower in the defunctioned ileum than in the functional ileum. Moreover, the healthy defunctioned ileum showed reductions in villous height, goblet cell numbers, and Ki-67+ cell numbers. Additionally, interferon-γ+, interleukin-17+, and immunoglobulin A+ cell abundance in the lamina propria decreased. After the intestinal environment was restored with an ileostomy closure, the impaired ileal homeostasis recovered. The defunctioned ileum samples from patients with Crohn's disease also showed reductions in interferon-γ+ and interleukin-17+ cell numbers. Fecal stream diversion reduced the abundance and diversity of intestinal bacteria. It also altered the intestinal mucosal barrier, similar to the alterations observed in germ-free animals. In patients with Crohn's disease, Th1 and Th17 cell numbers were attenuated, which suggests that the host-microbiome interaction is important in disease pathogenesis.

Ursolic acid reverses liver fibrosis by inhibiting NOX4/NLRP3 inflammasome pathways and bacterial dysbiosis

ABSTRACT Activation of the NOX4/NLRP3 inflammasome pathway has been associated with fibrosis in other organs. An imbalance in intestinal bacteria is an important driving factor of liver fibrosis through the liver-gut axis. This study aimed to explore whether the effect of ursolic acid (UA) on liver fibrosis was associated with the NOX4/NLRP3 inflammasome pathways and intestinal bacteria. Wild-type (WT), NLRP3−/- , and NOX4−/- mice and AP-treated mice were injected with CCI4 and treated with or without UA. The intestinal contents of the mice were collected and analyzed by 16S rRNA sequencing. UA alleviated liver fibrosis, which manifested as decreases in collagen deposition, liver injury, and the expression of fibrosis-related factors, and the expression of NOX4 and NLRP3 was significantly inhibited by UA treatment. Even after CCI4 injection, liver damage and fibrosis-related factors were significantly decreased in NLRP3−/-, NOX4−/- , and AP-treated mice. Importantly, the expression of NLRP3 was obviously inhibited in NOX4−/- and AP-treated mice. In addition, the diversity of intestinal bacteria and the abundance of probiotics in NLRP3−/- and NOX4−/- mice was significantly higher than those in WT mice, while the abundance of harmful bacteria in NLRP3−/- and NOX4−/- mice was significantly lower than that in WT mice. The NOX4/NLRP3 inflammasome pathway plays a crucial role in liver fibrosis and is closely associated with the beneficial effect of UA. The mechanism by which the NOX4/NLRP3 inflammasome pathway is involved in liver fibrosis may be associated with disordered intestinal bacteria.

Metagenomic analysis of intestinal microbiota in geese from different farming systems in Gunungpati, Semarang

The diversity of intestinal bacteria in geese correlates with environmental conditions, rearing methods, and consumed feeds. The intestinal bacteria composition is useful for the absorption of nutrition, improving the metabolism, and may be related to the immune system. This study was conducted to examine the intestinal bacteria composition and the diversity of maintained goose in aviaries and barns. This research was an observational exploratory. Five geese were taken purposively from local breeders in Gunungpati District, Semarang City. A total of 5 g of intestinal contents from each sample was used for microbial genome isolation. Then, the genome was amplified to collect 16S rRNA gene region V3-V4. The amplicons were then sequenced using the next generation sequencing (NGS) method (Illumina high-throughput sequencing; paired-end reads) and analyzed using QIIME2 to identify bacterial species. In addition, GC-MS was performed to identify and measure fatty acid contents in the intestinal. The results showed that both rearing and caged goose contained nine phyla of intestinal bacteria. The number of intestinal bacteria of barn geese (SU) reached 32,748 Operational Taxonomy Units (OTU); higher than aviary geese (SK), which was 11,646 OTU. The intestinal bacteria community in barn geese was approved by Phylum TM7 (Saccharibacteria candidate) (53.18%), followed by Firmicutes (32.51%) and Bacteriodetes (5.42%). Whereas on SK Firmicutes was compiled 49.3 4% of total OTU, TM7 (S. candidate) up to 21.17%, and Actinobacteria up to 15.99 %. The abundance of TM7 may contribute to high 9,12-octadecadienoic acid production, while Firmicutes was related to the high production of oleic acid. Based on these data, the reared geese had a more abundant diversity of bacteria than the caged one.

Intestinal flora imbalance affects bile acid metabolism and is associated with gallstone formation

BackgroundThe gut microbiota participates in the metabolism of substances and energy, promotes the development and maturation of the immune system, forms the mucosal barrier, and protects the host from pathogen attacks. Although the pathogenesis of cholesterol gallstones is still not clear, studies have suggested that gut microbiota dysbiosis plays an important role in their formation.MethodsMicrobial DNA from faeces of normal control patients and those of patients with calculi was subjected to 16S rRNA gene sequencing to detect gene expression changes in intestinal microbes. ELISA kits were used to measure free bile acids, secondary bile acids and coprostanol according to the manufacturer’s instructions. The relationship between flora and their metabolites was then analysed.ResultsIn the gallstone group, the diversity of intestinal bacteria and the abundances of certain phylogroups were significantly decreased (p < 0.05), especially Firmicutes (p < 0.05), the largest phylum represented by the gut microbiota. This study found an increase in free bile acids (p < 0.001) and secondary bile acids (p < 0.01) in the enterohepatic circulation. Bile salt hydrolase activity was not related to the abundances of BSH-active bacteria. 7a-dehydroxylating gut bacteria were significantly increased (p < 0.01), whereas cholesterol-lowering bacteria were significantly reduced (p < 0.05). The Ruminococcus gnavus group could be used as a biomarker to distinguish the gallstone group from the control group.ConclusionWe conclude that intestinal flora imbalance affects bile acid and cholesterol metabolism and is associated with gallstone formation.

Borealis awards engineering services (EPCM) contract to Maire Tecnimont Group for new world-scale propane dehydrogenation plant in Belgium

Intestinal microflora, as a component of the host bacteria ecosystem, can influence the healthy growth of crab. The aim of this study was to determine the intestinal microflora of the juvenile Chinese mitten crab Eriocheir sinensis with different feeding modes. We investigated the bacterial communities of crab intestine resulting from three different feeding modes using high-throughput sequencing technology, including traditional, formulated, and mixture (combined traditional and formulated) diet feeding modes. Intestinal microbiota biodiversity and richness were not affected by the different feeding modes. The most dominant community members at the phylum level were Tenericutes, Bacteroidetes, Firmicutes, and Proteobacteria. Significant differences were only observed in the relative abundance of Tenericutes (P = 0.0390) and Proteobacteria (P = 0.0273) in the female crab intestines among different feeding modes. The seven most abundant genera in the intestine of male and female crabs included Candidatus Bacilloplasma, Candidatus Hepatoplasma, Prolixibacter, Vibrio, Dysgonomonas, Coprobacillus, and Lactovum. Moreover, high average similarity of the microbial community was observed in the intestine of male and female crabs among the three different feeding modes and also between male and female crabs within these feeding modes. The most abundant genera in the latter (>10%) were Candidatus Bacilloplasma, Candidatus Hepatoplasma, and Prolixibacter. In addition, unique microbial genera were found in male or female crab intestine among different feeding modes. Differences were also observed in the relative enrichment of the dominant bacteria in male and female crab intestine among different feeding modes. Nevertheless, these findings suggested that the microbial communities in the intestines of crabs showed overall high average similarity among the three feeding modes or between the sexes as reflected by the biodiversity, richness of intestinal microbiota, and the most dominant community members at the phylum and genera levels. The results of this study provide a theoretical reference regarding the diversity of intestinal bacteria in juvenile E. sinensis.

Microbiota comparison in the intestine of juvenile Chinese mitten crab Eriocheir sinensis fed different diets

Intestinal microflora, as a component of the host bacteria ecosystem, can influence the healthy growth of crab. The aim of this study was to determine the intestinal microflora of the juvenile Chinese mitten crab Eriocheir sinensis with different feeding modes. We investigated the bacterial communities of crab intestine resulting from three different feeding modes using high-throughput sequencing technology, including traditional, formulated, and mixture (combined traditional and formulated) diet feeding modes. Intestinal microbiota biodiversity and richness were not affected by the different feeding modes. The most dominant community members at the phylum level were Tenericutes, Bacteroidetes, Firmicutes, and Proteobacteria. Significant differences were only observed in the relative abundance of Tenericutes (P = 0.0390) and Proteobacteria (P = 0.0273) in the female crab intestines among different feeding modes. The seven most abundant genera in the intestine of male and female crabs included Candidatus Bacilloplasma, Candidatus Hepatoplasma, Prolixibacter, Vibrio, Dysgonomonas, Coprobacillus, and Lactovum. Moreover, high average similarity of the microbial community was observed in the intestine of male and female crabs among the three different feeding modes and also between male and female crabs within these feeding modes. The most abundant genera in the latter (>10%) were Candidatus Bacilloplasma, Candidatus Hepatoplasma, and Prolixibacter. In addition, unique microbial genera were found in male or female crab intestine among different feeding modes. Differences were also observed in the relative enrichment of the dominant bacteria in male and female crab intestine among different feeding modes. Nevertheless, these findings suggested that the microbial communities in the intestines of crabs showed overall high average similarity among the three feeding modes or between the sexes as reflected by the biodiversity, richness of intestinal microbiota, and the most dominant community members at the phylum and genera levels. The results of this study provide a theoretical reference regarding the diversity of intestinal bacteria in juvenile E. sinensis.

Gut Dysbiosis and the Intestinal Microbiome: Streptococcus thermophilus a Key Probiotic for Reducing Uremia.

In the intestines, probiotics can produce antagonistic effects such as antibiotic–like compounds, bactericidal proteins such as bacteriocins, and encourage the production of metabolic end products that may assist in preventing infections from various pathobionts (capable of pathogenic activity) microbes. Metabolites produced by intestinal bacteria and the adoptions of molecular methods to cross-examine and describe the human microbiome have refreshed interest in the discipline of nephology. As such, the adjunctive administration of probiotics for the treatment of chronic kidney disease (CKD) posits that certain probiotic bacteria can reduce the intestinal burden of uremic toxins. Uremic toxins eventuate from the over manifestation of glucotoxicity and lipotoxicity, increased activity of the hexosamine and polyol biochemical and synthetic pathways. The accumulation of advanced glycation end products that have been regularly associated with a dysbiotic colonic microbiome drives the overproduction of uremic toxins in the colon and the consequent local pro-inflammatory processes. Intestinal dysbiosis associated with significant shifts in abundance and diversity of intestinal bacteria with a resultant and maintained uremia promoting an uncontrolled mucosal pro-inflammatory state. In this narrative review we further address the efficacy of probiotics and highlighted in part the probiotic bacterium Streptococcus thermophilus as an important modulator of uremic toxins in the gut of patients diagnosed with chronic kidney disease. In conjunction with prudent nutritional practices it may be possible to prevent the progression of CKD and significantly downregulate mucosal pro-inflammatory activity with the administration of probiotics that contain S. thermophilus.

Comparative analysis of gut bacterial communities in housefly larvae fed different diets using a high-throughput sequencing approach.

Housefly larvae are a synanthropic host for various bacteria, including pathogens and commensals and an important protein source for monogastric animal feed. Many factors, such as diets, life stages, host habitats can influence microbial community structure. In this study, the diversity of bacterial communities in the gut of housefly larvae fed on different artificial diets was comprehensively characterized using high-throughput sequencing with the aim shedding light on an optimal larval diet. The results showed that the dominant bacteria belonging to Proteobacteria, Firmicutes and Bacteroidetes phyla were related to polysaccharide degradation. The comparative analysis indicated that the dominant intestinal bacteria of larvae fed on high-protein were similar to those on high-fat diet. The same was the case in larvae fed high-starch diet and wheat bran alone. In addition, the diversity of intestinal bacteria at genus level in larvae fed high-protein and high-fat diet was higher than in larvae fed the other two diets. Further analysis indicated that the increase of potential commensals and decrease of pathogens in larvae fed on high-fat diet contributed to the increase of housefly larvae immunity. It established a foundation for further research on improvement of nutrition of housefly larvae used for poultry and fish feed.

The community structure of intestinal bacteria from cirrhosis patients and its influence factors

Objective To investigate the community structure of intestinal bacteria from patients with cirrhosis and its influencing factors. Methods From 2016 to 2017, 24 patients with liver cirrhosis (the LC group) and 23 healthy family members of patients (the HC group) were enrolled at the First Hospital of Lanzhou University. A comparative analysis of the community structure of intestinal bacteria was performed using 16S rRNA gene sequencing in LC and HC groups. Combined with LEfSe analysis and NMDS analysis, the differential markers were screened and the factors affecting the intestinal community structure of subjects were studied. Results The dominant six phylum of bacteria in intestines in LC and HC groups included Firmicutes, Bacteroides, Proteobacteria, Actinobacteria, Fusobacteria and Tenericumes. However, in the LC sample, Firmicutes was significantly reduced, while Bacteroides was significantly increased. The diversity of intestinal bacteria was significantly reduced, and the Firmicutes/Bacteroides ratio was significantly decreased, suggesting a variation of the community structure in intestinal bacteria of cirrhosis patients. The LEfSe result indicated that the abundance of Enterococcus, Lactobacillales, Bacilli, and Bacteroidetes showed a significant difference in the LC sample, which may be used as potential marked bacterial groups for cirrhosis. The NMDS analysis revealed a positive relationship between the concentration of Cd and Pb and the abundance of intestinal bacteria in the LC sample. Conclusion The community structure of intestinal bacteria from patients with cirrhosis has changed. Enterococcus, Lactobacillales, Bacilli, and Bacteroidetes are potential marked bacterial groups. The concentration of Cd and Pb in the intestinal tract of cirrhosis patients may interact with the abundance and structure of bacteria, and further affect the occurrence and development of cirrhosis. Key words: Cirrhosis; Intestinal bacteria; Bacterial community structure; Influencing factor