Abundance Of Intestinal Bacteria Research Articles

Acupuncture ameliorates inflammation by regulating gut microbiota in acute ischemic stroke.

Fine particulate matter (PM2.5) is associated with risks of liver diseases and intestinal bacterial dysbiosis, in which the gut-liver axis regulation mechanisms induced by PM2.5 exposure are still limited so far. In this study, after 12 weeks of exposure to atmospheric PM2.5 (64 μg/m3) and clean air in winter in Taiyuan, China, we collected liver and intestinal tissues and serum in male mice to perform toxicology experiments. The results showed that PM2.5 significantly exacerbated the pathological injury in the liver and intestine and liver fibrosis in mice, along with elevated levels of pro-inflammatory cytokines and lipopolysaccharide (LPS) levels in the serum. PM2.5 caused abnormal liver function and activated TLR4/NF-κB/NLRP3 pathway in mouse liver. PM2.5 also significantly inhibited the expression of intestinal mucosal tight junction proteins such as ZO-1 and occludin. Besides, from 16S rRNA gene sequencing results in intestinal and fecal samples, we found that PM2.5 decreased the diversity and abundance of intestinal bacteria, along with reducing Shannon, Chao1 and Ace indices and increasing Simpson indices. Principal component analysis (PCA) showed that mice's intestinal bacterial composition and β-diversity in the PM2.5-exposed group significantly differed from the control group. KEGG pathway analyzed key functional genes and metabolic pathways in important mouse bacterial communities in the PM2.5-exposed group. It suggested that PM2.5 exposure exacerbates liver fibrosis in mice via the NLRP3 pathway. PM2.5 caused intestinal mucosal injury, intestinal bacterial disorders and increased LPS levels, leading to the activation of inflammatory pathways, which can exacerbate liver fibrosis via the gut-liver axis.

5-Fluorouracil (5-FU) is commonly used as the primary chemotherapy for colorectal cancer (CRC). However, it can lead to unwanted chemoresistance. Resistant starch (RS), which functions similarly to fermentable dietary fiber, has the potential to reduce the risk of CRC. The effects of RS on improving CRC-associated cachectic symptoms and 5-FU chemotherapy-induced microbial dysbiosis remain unknown. Female BALB/cByJNarl mice were randomly divided into four groups: one tumor group (with CT26 colonic carcinoma but no treatment) and three CT26 colonic carcinoma-bearing groups that were administered 20 mg/kg 5-FU (T+5-FU group), a probiotic cocktail (4 × 108 CFUs) plus chemotherapy (T+5-FU+Pro), or resistant-starch-encapsulated probiotics plus chemotherapy (T+5-FU+RS-Pro). T+5-FU and T+5-FU+RS-Pro administration significantly suppressed tumor growth and activated apoptotic cell death in CT26-bearing mice. 5-FU-induced increases in inflammatory cytokines and NF-κB signaling were mitigated by the Pro or RS-Pro supplementation. A gut microbial composition comparison indicated that the abundance of intestinal bacteria in the T and T+5-FU groups decreased significantly, while the groups receiving Pro or RS-Pro maintained a greater abundance and healthy gut microbiota composition, suggesting that RS can reduce the microbial dysbiosis that occurs during 5-FU chemotherapy. The use of RS-Pro before chemotherapy should be considered for the regulation of chemotherapy-associated cachectic symptoms, inflammation, and chemotherapy-induced microbial dysbiosis.

To investigate the intestinal inflammatory response and the abundance of intestinal bacteria in rats with high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) and assess the intervention effects of taurine (TAU). Forty male Sprague-Dawley rats were randomly divided into five groups: group I, normal diet and normal saline gavage; group II, normal diet and TAU gavage; group III, HFD and normal saline gavage; group IV, HFD and TAU gavage (from the 1st week); group V, HFD and TAU gavage (from the 10th week). At the end of the 16th week, all the animals were sacrificed. Body weight, liver weight, liver function, and serum lipid levels were measured. The histopathologies of the liver and ileum were observed. The mRNA and protein expression levels of interleukin 17 (IL-17) and IL-10 in the ileum were detected by reverse transcription quantitative polymerase chain reaction (qPCR) and immunohistochemistry. Three types of bacteria were detected in intestinal feces using the 16S rDNA qPCR method. The ileal IL-17 level in group III was significantly higher than those in the other four groups (P < 0.01). The ileal IL-10 mRNA levels in group IV was significantly higher than those in groups III and V (P < 0.05), and IL-10 protein MOD levels in group III was significantly lower than those in the other four groups (P < 0.01). The numbers of Lactobacillus in group III were significantly lower than those in the other four groups (P < 0.01 or P < 0.05). The numbers of Bifidobacteria in groups IV and V were significantly increased compared with that in group III (P < 0.05). TAU may down-regulate the expression of IL-17, up-regulate the expression of IL-10 and regulate the intestinal flora, and alleviate the liver and intestinal damage in rats with HFD-induced NAFLD.

In this study, we investigated the ameliorative gut modulatory effect of carboxymethylated Lycium barbarum seed dreg insoluble dietary fiber (LBSDIDF) on hyperlipidemic mice. After seven weeks of insoluble dietary fiber (IDF) intervention, the results demonstrated that IDFs effectively inhibited body weight gain, with slimming and hypolipidemic effects, and improved liver histopathology by decreasing ALT, AST, TNF-α and IL-6, and increasing short-chain fatty acid (SCFA) levels in hyperlipidemic mice. With the increasing diversity and abundance of intestinal bacteria and decreasing ratio of Firmicutes to Bacteroidetes, intestinal flora facilitated cholesterol lowering effects in hyperlipidemic mice. Our research offers a novel concept for the use of LBSDIDF as a prebiotic to improve intestinal dysbiosis or as a preventive measure against obesity and dyslipidemia.

A direct correlation has been reported between excessive fat intake and the development and progression of various enteropathies. Plant foods may contain bioactive compounds and non-digestible dietary fiber, with potential to improve intestinal health. Chia is a good source of dietary fiber and bioactive compounds. Our study evaluated the role of chia flour associated with a high-fat diet (HFD) on colon histomorphometry, intestinal functionality and intestinal microbiome composition and function in Wistar rats. The study used 32 young male rats separated into four groups to receive a standard diet (SD) or HFD, with or without chia, for 35 days. At the end of the study, the cecum, cecal content and duodenum were collected. The consumption of chia increased the production of short-chain fatty acids and improved fecal moisture. Chia consumption improved the circular muscle layer in the SD group. The diversity and abundance of intestinal bacteria were not affected, but increased richness was observed in the microbiome of the SD+chia group. Moreover, chia consumption decreased the expression of proteins involved in intestinal functionality. Chia consumption improved intestinal morphology and functionality in young Wistar rats but was insufficient to promote significant changes in the intestinal microbiome in a short term of 35 days.

Observational findings achieved that gut microbes mediate human metabolic health and disease risk. The types of intestinal microorganisms depend on the intake of food and drugs and are also related to their metabolic level and genetic factors. Recent studies have shown that chronic inflammatory pain is closely related to intestinal microbial homeostasis. Compared with the normal intestinal flora, the composition of intestinal flora in patients with chronic inflammatory pain had significant changes in Actinomycetes, Firmicutes, Bacteroidetes, etc. At the same time, short-chain fatty acids and amino acids, the metabolites of intestinal microorganisms, can regulate neural signal molecules and signaling pathways, thus affecting the development trend of chronic inflammatory pain. Glucocorticoids and non-steroidal anti-inflammatory drugs in the treatment of chronic inflammatory pain, the main mechanism is to affect the secretion of inflammatory factors and the abundance of intestinal bacteria. This article reviews the relationship between intestinal microorganisms and their metabolites on chronic inflammatory pain and the possible mechanism.

The influence of diet on the composition of the intestinal microbiota and related pathologies has been known for some time. Some classes of nutrients, such as fatty acids belonging to the omega 3 series, have particular effects on the bacteria that make up the intestinal microbiota. ω-3 PUFAs affect the gut microbiota in three different ways: by modulating the type and abundance of intestinal bacteria, by regulate SCFAs levels, and by alter the levels of proinflammatory mediators. Through these modalities, ω-3 PUFAs could be useful for the prevention of intestinal diseases such as Colorectal Cancer (CRC). The ability of ω-3 PUFAs to modulate the intestinal inflammatory response, to preserve the integrity of the intestinal mucosa and to modulate the bacterial composition of the intestine, could be useful as a preventive strategic approach to hinder the development of CRC.

Consumption of 85% cocoa dark chocolate improves mood in association with gut microbial changes in healthy adults: a randomized controlled trial

Egg white ovomucin (OVM) is homologically related to MUC2, the key component of colonic mucous layer. This study investigated the effects of orally administered OVM from egg white on the colonic mucosal barrier and the development of colitis using a colitis C57BL/6J mice model. The results showed that daily supplementation of 125 and 250 mg/kg BW of OVM partially relieved the villous destruction and loss of intestinal barrier integrity, and hence decreased the epithelial barrier permeability. The supplementation also reduced the secretion of proinflammatory cytokines TNF-α and IL-6. Besides, OVM administration significantly increased the relative abundance of intestinal beneficial bacteria including Lactobacilli, Faecalibaculum, Ruminococcus, etc. and further upregulated the production of bacterial metabolites such as short-chain fatty acids (SCFAs), which is a direct source of energy for the proliferation of epithelia and goblet cells. In conclusion, OVM from egg white ameliorates colitis by enhancing the intestinal barrier function and abundance of intestinal bacteria, thereby increasing the number of SCFAs.

Intestinal bacteria are involved in Radix Glycyrrhizae and Radix Euphorbiae Pekinensis incompatibility

This study aimed to investigate the intestinal microbiota in duodenal ulcer (DU) patients, effects of proton pump inhibitors,clarithromycin and amoxicillin, PCA) for Helicobacter pylori (H. pylori) and Bacillus subtilis and Enterococcus faecium (BSEF) on intestinal microbiota. DU patients were randomly assigned to receive either PCA (group TT) or PCA plus BSEF(group TP). The fecal microbiome was conducted using high throughput 16S rDNA gene and internal transcribed spacer sequencings. The diversity and abundance of intestinal bacteria in the DU were significantly lower than health check control (HC) group. In the TT group, the abundance and diversity of both intestinal bacteria and fungi decreased after PCA treatment, compared with those before treatment, whereas in the TP group no obvious changes were observed. In the TT group at all the time points, both the intestinal bacteria and fungi were different from those in the HC group. However, in the TP group, at 10w the bacterial flora abundance was close to that in the HC group. The results indicate that anti- H. pylori treatment induced significant decrease in the diversity of intestinal microbiota, while the combined therapy supplemented with BSEF could protect and restore the intestinal microbiota.

Effect of dietary xylan on immune response, tight junction protein expression and bacterial community in the intestine of juvenile turbot (Scophthalmus maximus L.)

Intestinal dysbacteriosis mediates the reference memory deficit induced by anaesthesia/surgery in aged mice

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

This study was conducted to determine effects of dietary supplementation with 1 % L-glutamine for 14 days on the abundance of intestinal bacteria and the activation of intestinal innate immunity in mice. The measured variables included (1) the abundance of Bacteroidetes, Firmicutes, Lactobacillus, Streptococcus and Bifidobacterium in the lumen of the small intestine; (2) the expression of toll-like receptors (TLRs), pro-inflammatory cytokines, and antibacterial substances secreted by Paneth cells and goblet cells in the jejunum, ileum and colon; and (3) the activation of TLR4-nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPK), and phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt) signaling pathways in the jejunum and ileum. In the jejunum, glutamine supplementation decreased the abundance of Firmicutes, while increased mRNA levels for antibacterial substances in association with the activation of NF-κB and PI3K-Akt pathways. In the ileum, glutamine supplementation induced a shift in the Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes, and enhanced mRNA levels for Tlr4, pro-inflammatory cytokines, and antibacterial substances participating in NF-κB and JNK signaling pathways. These results indicate that the effects of glutamine on the intestine vary with its segments and compartments. Collectively, dietary glutamine supplementation of mice beneficially alters intestinal bacterial community and activates the innate immunity in the small intestine through NF-κB, MAPK and PI3K-Akt signaling pathways.