Protective Mechanism of Eurotium amstelodami from Fuzhuan Brick Tea against Colitis and Gut-Derived Liver Injury Induced by Dextran Sulfate Sodium in C57BL/6 Mice

The study explored the potential protective impact of the probiotic fungus Eurotium amstelodami in Fuzhuan brick tea on ulcerative colitis, along with the underlying mechanism. A spore suspension of E. amstelodami was administered to C57BL/6 mice to alleviate DSS-induced colitis. The findings indicated that administering E. amstelodami evidently enhanced the ultrastructure of colonic epithelium, showing characteristics such as enhanced TJ length, reduced microvilli damage, and enlarged intercellular space. After HLL supplementation, the activation of the liver inflammation pathway, including TLR4/NF-kB and NLRP3 inflammasome caused by DSS, was significantly suppressed, and bile acid metabolism, linking liver and gut, was enhanced, manifested by restoration of bile acid receptor (FXR, TGR5) level. The dysbiosis of the gut microbes in colitis mice was also restored by HLL intervention, characterized by the enrichment of beneficial bacteria (Lactobacillus, Bifidobacterium, Akkermansia, and Faecalibaculum) and fungi (Aspergillus, Trichoderma, Wallemia, Eurotium, and Cladosporium), which was closely associated with lipid metabolism and amino acid metabolism, and was negatively correlated with inflammatory gene expression. Hence, the recovery of gut microbial community structure, implicated deeply in the inflammatory index and metabolites profile, might play a crucial role in the therapeutic mechanism of HLL on colitis.

Faecalibacterium prausnitzii Supplementation Prevents Intestinal Barrier Injury and Gut Microflora Dysbiosis Induced by Sleep Deprivation

Sleep deprivation (SD) leads to impaired intestinal barrier function and intestinal flora disorder, especially a reduction in the abundance of the next generation of probiotic Faecalibacterium prausnitzii (F. prausnitzii). However, it remains largely unclear whether F. prausnitzii can ameliorate SD-induced intestinal barrier damage. A 72 h SD mouse model was used in this research, with or without the addition of F. prausnitzii. The findings indicated that pre-colonization with F. prausnitzii could protect against tissue damage from SD, enhance goblet cell count and MUC2 levels in the colon, boost tight-junction protein expression, decrease macrophage infiltration, suppress pro-inflammatory cytokine expression, and reduce apoptosis. We found that the presence of F. prausnitzii helped to balance the gut microbiota in SD mice by reducing harmful bacteria like Klebsiella and Staphylococcus, while increasing beneficial bacteria such as Akkermansia. Ion chromatography analysis revealed that F. prausnitzii pretreatment increased the fecal butyrate level in SD mice. Overall, these results suggested that incorporating F. prausnitzii could help reduce gut damage caused by SD, potentially by enhancing the intestinal barrier and balancing gut microflora. This provides a foundation for utilizing probiotics to protect against intestinal illnesses.

Chitosan oligosaccharide improves intestinal homeostasis to achieve the protection for the epithelial barrier of female Drosophila melanogaster via regulating intestinal microflora

Chitosan oligosaccharide (COS) is a new type of marine functional oligosaccharide with biological activities such as regulating intestinal microflora and improving intestinal immunity. In this study, female Drosophila melanogaster was used as a model organism to evaluate the effect of COS on intestinal injury by H2O2 induction, and its mechanism was explored through the analysis of intestinal homeostasis. The results showed that 0.25% of COS could effectively prolong the lifespan of stressed female D. melanogaster by increasing its antioxidant capacity and maintaining intestinal homeostasis, which included protecting the mechanical barrier, promoting the chemical barrier, and regulating the biological barrier by affecting its autophagy and the antioxidant signaling pathway. Additionally, the protective effect of COS on the intestinal barrier and homeostasis of D. melanogaster under oxidative stress status is directly related to its regulation of the intestinal microflora, which could decrease excessive autophagy and activate the antioxidant system to promote health.

IMPORTANCE

The epithelial barrier plays an important role in the organism's health. Chitosan oligosaccharide (COS), a new potential prebiotic, exhibits excellent antioxidant capacity and anti-inflammatory effects. Our study elucidated the protective mechanisms of COS on the intestinal barrier of Drosophila melanogaster under oxidative stress, which could provide new insights into COS application in various industries, such as food, agriculture, and medicine.

Asiaticoside ameliorates DSS-induced colitis in mice by inhibiting inflammatory response, protecting intestinal barrier and regulating intestinal microecology

Ulcerative colitis (UC) is one of the most prevalent inflammatory bowel diseases and poses a serious threat to human health. Currently, safe and effective preventive measures are unavailable. In this study, the protective effects of asiaticoside (AS) on dextran sodium sulfate (DSS)-induced colitis in mice and the underlying molecular mechanism were investigated. In this experiment, colitis was induced in mice with DSS. Subsequently, the role of AS in colitis and its underlying mechanisms were examined using H&E staining, immunofluorescence staining, western blot, Elisa, FMT, and other assays. The results showed that AS significantly attenuated the related symptoms of DSS-induced colitis in mice. In addition, AS inhibited the activation of signaling pathways TLR4/NF-κB and MAPK reduced the release of inflammatory factors, thereby attenuating the inflammatory response in mice. AS administration also restored the permeability of the intestinal barrier by increasing the levels of tight junction-associated proteins (claudin-3, occludin, and ZO-1). In addition, AS rebalanced the intestinal flora of DSS-treated mice by increasing the diversity of the flora. AS can alleviate DSS-induced ulcerative colitis in mice by maintaining the intestinal barrier, thus inhibiting the signaling pathways TLR4/NF-κB and MAPK activation, reducing the release of inflammatory factors, and regulating intestinal microecology.

Multi-omics analysis of miRNA-mediated intestinal microflora changes in crucian carp Carassius auratus infected with Rahnella aquatilis

Infection by an emerging bacterial pathogen Rahnella aquatilis caused enteritis and septicemia in fish. However, the molecular pathogenesis of enteritis induced by R. aquatilis infection and its interacting mechanism of the intestinal microflora associated with microRNA (miRNA) immune regulation in crucian carp Carassius auratus are still unclear. In this study, C. auratus intraperitoneally injected with R. aquatilis KCL-5 was used as an experimental animal model, and the intestinal pathological changes, microflora, and differentially expressed miRNAs (DEMs) were investigated by multi-omics analysis. The significant changes in histopathological features, apoptotic cells, and enzyme activities (e.g., lysozyme (LYS), alkaline phosphatase (AKP), alanine aminotransferase (ALT), aspartate transaminase (AST), and glutathione peroxidase (GSH-Px)) in the intestine were examined after infection. Diversity and composition analysis of the intestinal microflora clearly demonstrated four dominant bacteria: Proteobacteria, Fusobacteria, Bacteroidetes, and Firmicutes. A total of 87 DEMs were significantly screened, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that the potential target genes were mainly involved in the regulation of lipid, glutathione, cytosine, and purine metabolism, which participated in the local immune response through the intestinal immune network for IgA production, lysosome, and Toll-like receptor (TLR) pathways. Moreover, the expression levels of 11 target genes (e.g., TLR3, MyD88, NF-κB, TGF-β, TNF-α, MHC II, IL-22, LysC, F2, F5, and C3) related to inflammation and immunity were verified by qRT-PCR detection. The correlation analysis indicated that the abundance of intestinal Firmicutes and Proteobacteria was significantly associated with the high local expression of miR-203/NF-κB, miR-129/TNF-α, and miR-205/TGF-β. These findings will help to elucidate the molecular regulation mechanism of the intestinal microflora, inflammation, and immune response-mediated miRNA-target gene axis in cyprinid fish.

Synergistic impact of Gui Zhi Shao Yao Zhi Mu Decoction and leflunomide on gut microbiota in rheumatoid arthritis: insights from 16S rDNA sequencing

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease with complex pathogenesis, including alterations in the gut microbiota. Gui Zhi Shao Yao Zhi Mu Decoction (GSZD), a traditional Chinese herbal formula, has shown efficacy in RA treatment, but its impact on intestinal microflora remains unclear. This study aimed to investigate the effects of GSZD combined with leflunomide on the gut microbiota of RA patients.

METHODS

The study enrolled 48 RA patients who were randomly assigned to either a control group receiving leflunomide or a treatment group receiving GSZD combined with leflunomide for 12 weeks. Gut microbiota composition was analyzed pre- and post-intervention using 16S rDNA sequencing. Changes in microbial diversity, abundance, and metabolic functions were assessed.

RESULTS

Post-treatment, both groups exhibited significant alterations in gut microbiota composition. GSZD combined with leflunomide led to an increased Bacteroidetes/Firmicutes ratio and a reduction in Actinobacteria compared to leflunomide alone. This was associated with beneficial shifts in microbial genera and metabolic pathways, suggesting improved gut health and systemic immune modulation.

CONCLUSION

GSZD combined with leflunomide significantly modulates the gut microbiota in RA patients. This study provides insights into the mechanisms underlying the therapeutic effects of GSZD and highlights the potential of integrating traditional Chinese medicine with conventional treatments in managing RA.

Comparative Effects on Using Bilberry Leaves in Broiler Diet Reared under Thermoneutral Conditions vs. Heat Stress on Performance, Health Status and Gut Microbiota

The study aims to investigate the impact of dietary bilberry leaves on the performance, health status, and gut microbiota of broilers reared in both thermoneutral conditions and under heat stress. Sixty Cobb 500 broiler chicks were divided into two groups (C-TN, BL-TN) and reared in thermoneutral conditions for the first trial. For the second trial, two other groups (C-HS and BL-HS) were reared in heat stress (32 °C), with 30 chickens in each group. The experimental diets were supplemented with 1% bilberry leaves compared to the control diets. The broilers fed a diet with bilberry leaves had lower levels of cholesterol compared to the control birds. At the end of the experiment, six broilers per group were slaughtered, and intestinal contents were collected for bacteriological analyses. The results revealed that bilberry leaves increased body weight and average daily feed intake in the BL-TN group compared to the C-HS group. However, the broilers fed a bilberry leaves diet and reared in heat stress had a significantly lower average daily feed intake and average daily weight gain than the C-TN group. Additionally, the number of staphylococci colonies decreased significantly in the group fed with a BL-supplemented diet and reared in TN compared to C-TN, while lactobacilli increased significantly in BL-TN compared to C-TN. In summary, bilberry leaves can be used as a natural supplement in a broiler's diet to regulate serum cholesterol in heat stress and maintain the health of intestinal microflora in thermoneutral conditions.

Baizhu-Baishao herb pair ameliorates functional constipation and intestinal microflora disorder in rats

BACKGROUND

In China, Rhizoma atractylodis macrocephalae-Paeonia lactiflora Pall (Biazhu-Baishao, BZBS) is a classic herb pair used to treat intestinal stress syndrome, ulcerative colitis and other diseases. However, the mechanism of BZBS in the treatment of functional constipation (FC) has been little studied and remains unclear. In this study, a behavioral investigation, colon tissue morphology, enzyme-linked immunosorbent assay (Elisa) and intestinal microflora analysis have been used to illuminate the potential mechanism of the effects of BZBS on FC in a rat model.

METHODS

A FC rat model was constructed and BZBS was given as treatment. Observations and recordings were made of the fecal moisture content, the defecation time of the first black stool, and the rate of intestinal propulsion. Elisa was used to detect the expression levels of substance P (SP), vasoactive intestinal peptide (VIP), 5-hydroxytryptamine (5-HT) in the colon. To ascertain the composition of the microbial community, a high throughput 16S ribosomal RNA (16S rRNA) gene sequencing technique was employed.

RESULTS

Oral administration of BZBS significantly ameliorated several key excretion parameters, including the time to first black stool defecation, stool water content, and the propulsion rate in the small intestine in FC rats. It increased the expression of SP, VIP and 5-HT in the colon. 16S rRNA gene sequencing results showed that BZBS changed the microbial community structure, decreased the Bacteroidetes/Firmicutes ratio, increased the relative abundance of Blautia and Fusicatenibacter, and decreased the relative abundance of Ruminococcus and Roseburia.

CONCLUSIONS

BZBS effectively alleviates FC and improves dysbacteriosis.

Effects of Low Protein Diet on Production Performance and Intestinal Microbial Composition in Pigs

In order to study the effects of a low protein diet on the production performance and intestinal microbiota composition of Hexi pigs, twenty-seven Hexi pigs with an initial body weight of 60.50 ± 2.50 kg were randomly divided into three groups (control group (CG), group 1 (G1), and group 2 (G2)) and participated in a 60-day finishing trial. The CG was fed a normal protein level diet with a protein level of 16.0%, and G1 and G2 were fed a low protein level diet with protein levels of 14.0% and 12.0%, respectively. The results showed that the low protein level diet had no significant effect on the production performance of Hexi pigs, compared with the CG, the slaughter rate of G1 and G2 increased by 2.49% (p > 0.05) and 6.18% (p > 0.05), the shear force decreased by 2.43% (p > 0.05) and 15.57% (p > 0.05), the cooking loss decreased by 24.02% (p < 0.05) and 21.09% (p > 0.05), and the cooking percentage increased by 13.20% (p > 0.05) and 11.59% (p > 0.05). From 45 min to 24 h and 48 h after slaughter, each group of pH decreased by 1.02, 0.66, and 0.42. For muscle flesh color, the lightness (L) increased by 13.31% (p > 0.05) and 18.01% (p > 0.05) in G1 and G2 and the yellowness (b) increased by 7.72% (p > 0.05) and 13.06% (p > 0.05). A low protein level diet can improve the intestinal flora richness and diversity of growing and finishing pigs. In the jejunum, the ACE index (899.95), Simpson index (0.90), and Shannon (4.75) index were higher in G1 than in the other groups, but the Chao1 index (949.92) was higher in G2 than in the remaining two groups. Proteobacteria, Actinobacteria, Euryarchaeota, and Verrucomicrobia were significantly higher in G1 than in the CG. The relative abundances of Lactobacillus, Terrisporobacter, and Megasphaera in G1 was significantly higher than in the CG (p < 0.05). In the cecum, the ACE index (900.93), Chao1 index (879.10), Simpson index (0.94), and Shannon (5.70) index were higher in G1 than in the remaining groups. The Spirochaetes in G2 were significantly higher than in the other groups, but the Verrucomicrobia was significantly lower than in the other groups. The relative abundances of Lactobacillus were higher in G1 and G2 than in the CG (p > 0.05). The relative abundances of unidentified_Clostridiales and Terrisporobacter in G2 were significantly lower than in the CG (p < 0.05). The relative abundance of Turicibacter in G1 was significantly lower than in the CG (p < 0.05). The relative abundances of other bacterial genera in G1 and G2 were increased by 30.81% (p > 0.05) and 17.98% (p > 0.05).

Phlorizin Mitigates Dextran Sulfate Sodium-Induced Colitis in Mice by Modulating Gut Microbiota and Inhibiting Ferroptosis

Phlorizin (PHZ) is the main active component of apple peel and presents a potential application value. In the past few years, some reports have suggested that PHZ may have antioxidant and anti-inflammatory effects. Herein, we have attempted to assess the protective effects of PHZ on dextran sodium sulfate (DSS)-induced colitis in mice and to determine the underlying molecular mechanisms. Our results suggested that early intervention with PHZ (20, 40, and 80 mg/kg) significantly reduced the severity of DSS-induced colitis in mice, as presented by a longer colon, improved tight junction protein, decreased disease activity index, and attenuated inflammatory factors. Additionally, early intervention with + (20, 40, and 80 mg/kg) significantly inhibited ferroptosis by decreasing the surrogate ferroptosis marker levels (MDA and Iron Content). Additionally, PHZ (80 mg/kg) increased the diversity of intestinal flora in colitic mice by elevating the levels of beneficial bacteria (Lactobacillaceae and Muribaculaceae) and reducing the levels of harmful bacteria (Lachnospiraceae). This indirectly led to an increase in the amount of short-chain fatty acids. A fecal microbial transplantation (FMT) test was conducted to show that PHZ (80 mg/kg) ameliorated ulcerative colitis (UC) by regulating gut dysbiosis. In conclusion, early intervention with PHZ decreased DSS-induced colitis in mice by preserving their intestinal barrier and regulating their intestinal flora.

Impact of Ocean Acidification on the Gut Histopathology and Intestinal Microflora of Exopalaemon carinicauda

Marine crustaceans are severely threatened by environmental factors such as ocean acidification, but, despite the latter's negative impact on growth, molting, and immunity, its effects on intestinal microflora remain poorly understood. This work studied the gut morphology and intestinal microflora of Exopalaemon carinicauda, grown in seawater of different pH levels: 8.1 (control group), 7.4 (AC74 group), and 7.0 (AC70 group). Ocean acidification was found to cause intestinal damage, while significantly altering the microflora's composition. However, the α-diversity did not differ significantly between the groups. At the phylum level, the relative abundance of Proteobacteria decreased in the acidification groups, while at the genus level, the relative abundance of Sphingomonas decreased. Babeliales was a prominent discriminative biomarker in the AC74 group, with Actinobacteriota, Micrococcales, Beijerinckiaceae, Methylobacterium, and Flavobacteriales being the main ones in the AC70 group. The function prediction results also indicated an enrichment of pathways related to metabolism for the acidification groups. At the same time, those related to xenobiotics' biodegradation and metabolism were inhibited in AC74 but enhanced in AC70. This is the first study examining the impact of ocean acidification on the intestinal microflora of crustaceans. The results are expected to provide a better understanding of the interactions between shrimp and their microflora in response to environmental stressors.

Anti-PD-1 therapy for advanced colorectal cancer based on intestinal microecology

To explore the effects of anti-programmed death-1 (PD-1) therapy on advanced colorectal cancer (CRC) based on the intestinal microecology. Ninety-two patients with advanced CRC were selected. Patients were treated with Apatinib alone or anti PD-1 treatment combined with Apatinib. The lactulose/mannitol (L/M) value of the urine was detected by high performance liquid chromatography. The changes of intestinal microflora were determined by real-time fluorescence quantitative PCR. The risk factors were analyzed through multivariate logistic regression analysis. The curative effect of anti PD-1 treatment combined with the Apatinib treatment (82.61%) was much higher than that of the Apatinib treatment alone (63.04%, p < 0.05). After treatment, the contents of Bifidobacterium, Lactobacillus, and Enterococcus faecalis were higher with lower levels of Escherichia coli in the observation group than the control (p < 0.05). The level of D-lactic acid and urinary L/M value of the urine in the observation group was lower than that in control after treatment (p < 0.001). The patients had a 3-year survival rate of 91.30%. Age >60 years old, histological types of mucinous adenocarcinoma and signet ring cell carcinoma, vascular tumor thrombus, nerve invasion, TNM stage of Ⅲ-Ⅳ were independent risk factors, and anti PD-1 treatment was the protective factor (p < 0.05). In advanced CRC patients receiving anti PD-1 treatment combined with the Apatinib treatment, the progression of advanced CRC was effectively controlled by maintaining the intestinal microflora balance. Anti PD-1 therapy can improve the living quality of CRC patients.

Eucommia ulmoides Oliver repairs the disorder of intestinal microflora caused by high starch in Micropterus salmoides and improves resistance to pathogens

Eucommia ulmoides Oliver (EuO) is a natural medicine that can improve the composition of intestinal flora in fish, but more experiments and data are needed to support whether it can effectively improve the changes of intestinal flora and intestinal damage caused by high starch. This study examined the changes in intestinal structure as well as intestinal flora before and after the addition of EuO to high-starch diets and analyzed the effects of such changes on immune and digestive functions. The results showed that EuO reduces mortality during Nocardia seriolae attack and can reduce starch-induced intestinal inflammation. Eucommia ulmoides Oliver supplementation was able to alter the changes of intestinal flora in fatty acid degradation, bacterial chemotaxis, porphyrin metabolism and flagella assembly caused by high starch. By analyzing the abundance and correlation of bacterial communities, three bacterial communities that were significantly related to the intervention effect of EuO were screened. Further analysis revealed that EuO supplementation reduced the increase in abundance of Limnochordaceae, Nitrolancea, Lysinibacillus, and Hydrogenispora induced by high starch, which were negatively correlated with levels of the immunoreactive substance LZM in fish. This study reveals the regulatory effects of EuO on the intestinal flora of Micropterus salmoides fed on high starch diets, and provides a theoretical basis for reducing starch damage to fish in production.

Effects of Lactobacillus plantarum Postbiotics on Growth Performance, Immune Status, and Intestinal Microflora of Growing Minks

The present experiment was conducted to investigate the effects of Lactobacillus plantarum postbiotics on growth performance, immune status, and intestinal microflora of growing minks. A total of 80 minks (40 males and 40 females) were divided into four groups, each group contained 20 minks (10 males and 10 females). The minks in the four groups were fed a basal diet supplemented with 0, 0.15%, 0.3%, and 0.45% Lactobacillus plantarum postbiotics (PLP), respectively. After one week of adaptation, the experiment ran for eight weeks. The results showed that Lactobacillus plantarum postbiotics tended to have effects on average daily again (ADG) during the first 4 wk of the study (p < 0.1), and had effects on immune status (p < 0.05). Lactobacillus plantarum postbiotics also affected the abundance of intestinal bacteria at genus level (p < 0.05), but had no effects on α diversity of growing minks (p > 0.05). Compared to the minks in the control group, minks in 0.30% PLP group tended to have greater ADG, and IgA and IgM content in serum as well as SIgA content in jejunal mucosa (p < 0.05), and had less jejunal mucosal TNF-α and IL-8 levels, while minks in 0.45% PLP group had less IL-2 (p < 0.05). Compared to the control, Lactobacillus plantarum postbiotics decreased the relative abundances of Bacteroides_vulgatus and Luteimonas_sp. in male minks, and the relative abundances of Streptococcus_halotolerans in female minks (p < 0.05), respectively. Males grew faster and ate more associated with less F/G than females (p < 0.05). Males also had greater serum IgA and IgG content (p < 0.05), and males had less jejunal mucosal IL-1β, IL-8, IL-2, IL-6, IL-12, IL-10, TNF-α, and IFN-γ levels (p < 0.05). These results suggest that dietary supplementation of 0.3% postbiotics harvested from Lactobacillus plantarum could improve growth performance and immune status, and modulated the intestinal bacteria abundance of growing minks.

Effects of Clostridium butyricum on Intestinal Microflora and Metabolism of Eriocheir sinensis

Clostridium butyricum, a new probiotic in recent years, can produce butyric acid and short-chain fatty acids. It has the characteristics of strong acid and alkali resistance, high temperature resistance, and strong resistance to most antibiotics, and has more advantages than other probiotics. However, the action mechanism of C. butyricum on Eriocheir sinensis is still unclear and needs further study. In this study, when C. butyricum was added to the basic diet, the number of living bacteria was 0, 1 × 106 and 1 × 108 CFU/g, respectively. The E. sinensis were randomly divided into three groups: (blank control group, experimental group 1 (1 × 106 CFU/g) and experimental group 2 (1 × 108 CFU/g)). They were fed an experimental diet for 28 days. The effects of C. butyricum on E. sinensis were studied by detecting the differences in non-specific immune indexes, intestinal microflora, and metabolites between serum and hepatopancreas. The results showed that C. butyricum could improve the antioxidant ability of E. sinensis serum and hepatopancreas, protect intestinal tissues, and promote the absorption of nutrients. At the same time, it can enhance the microbial diversity and richness of the E. sinensis gut flora. LC-MS metabolomics was used to detect the metabolism of intestinal flora. It was found that C. butyricum could up-regulate lysophosphatidylcholine in the intestine. Through the KEGG enrichment pathway, it was found that significantly different metabolites were mainly concentrated in six metabolic pathways. The purine metabolism and alanine, aspartate, and glutamate metabolism pathways showed a downward trend, indicating that the addition of C. butyricum to feed could reduce purine metabolism, promote the water-salt balance of the organism's cells, and reduce inflammation. In this study, it was found that the addition of certain concentrations of C. butyricum to feed could improve the antioxidant ability of E. sinensis, improve the intestinal flora environment, and promote the growth of beneficial bacteria in the gut. This can promote the body's metabolism, which is more conducive to its growth.

Evaluating the In Vitro and In Vivo Prebiotic Effects of Different Xylo-Oligosaccharides Obtained from Bamboo Shoots by Hydrothermal Pretreatment Combined with Endo-Xylanase Hydrolysis

Xylo-oligosaccharides (XOS) enriched with high fractions of X2-X3 are regarded as an effective prebiotic for regulating the intestinal microflora. In this study, the original XOS solution was obtained from bamboo shoots through hydrothermal pretreatment under optimized conditions. Subsequently, enzymatic hydrolysis with endo-xylanase was performed on the original XOS solution to enhance the abundance of the X2-X3 fractions. The results demonstrated that hydrothermal pretreatment yielded 21.24% of XOS in the hydrolysate solution, and subsequent enzymatic hydrolysis significantly increased the proportion of the X2-X3 fractions from 38.87% to 68.21%. Moreover, the XOS solutions with higher amounts of X2-X3 fractions exhibited superior performance in promoting the growth of probiotics such as Bifidobacterium adolescentis and Lactobacillus acidophilus in vitro, leading to increased production of short-chain fatty acids. In the in vivo colitis mouse model, XOS solutions with higher contents of X2-X3 fractions demonstrated enhanced efficacy against intestinal inflammation. Compared with the colitis mice (model group), the XOS solution with higher X2-X3 fractions (S1 group) could significantly increase the number of Streptomyces in the intestinal microflora, while the original XOS solution (S2 group) could significantly increase the number of Bacteroides in the intestinal microflora of colitis mice. In addition, the abundances of Alcaligenes and Pasteurella in the intestinal microflora of the S1 and S2 groups were much lower than in the model group. This effect was attributed to the ability of these XOS solutions to enhance species diversity, reversing the imbalance and disorder within the intestinal microflora. Overall, this work highlights the outstanding potential of XOS enriched with high contents of X2-X3 fractions as a regulator of the intestinal microbiota and as an anti-colitis agent.

Mouse Model of Anti-Obesity Effects of Blautia hansenii on Diet-Induced Obesity

Reportedly, a relationship exists between intestinal microflora and obesity-related lifestyle diseases. Blautia spp. a major intestinal microbiota, accounts for 3-11% of human intestinal microflora. Epidemiological reports have described that people with more visceral fat have less Blautia hansenii in their intestinal tract irrespective of age or gender. However, the effect of oral administration of heat-sterilized Blautia hansenii on obesity has not been clarified. Therefore, the aim of this study was to evaluate the effects of dietary Blautia hansenii administration on obesity in high-fat-diet-induced obesity in a mouse model. Heat-sterilized cells of Blautia hansenii were used. C57BL/6J mice (normal mice, n = 7) were fed with each experimental diet for nine weeks. Diets for experimentation were: normal-fat (NF) diets, high-fat (HF) diets, and high-fat + Blautia hansenii (HF + Blautia) diets. The HF + Blautia group was administered about 1 × 109 (CFU/mouse/day) of Blautia hansenii. During the periods of experimentation, body weight, food intake, water consumption, and fecal weight were recorded, and glucose tolerance tests were performed. Subsequently, the white adipose tissue (WAT) weight and serum components were measured. Short-chain fatty acid contents in the feces and cecum were analyzed. Furthermore, changes in the intestinal microflora were analyzed using meta-genomics analysis. Results showed that the total weight of WAT in the HF + Blautia group was significantly lower (13.2%) than that of the HF group. Moreover, the HF + Blautia group exhibited better glucose tolerance than the HF group. Productivity of short-chain fatty acids in the intestinal tract was at a significantly (p < 0.05) low level in the HF group; on the other hand, it recovered in the HF + Blautia group. Furthermore, there was a higher ratio of Blautia (p < 0.05) in the intestinal tracts of the HF + Blautia group than in the HF group. These results suggest that Blautia hansenii administration suppresses obesity induced by a high-fat diet.

Synergistic mediating effect of edible fungal polysaccharides (Auricularia and Tremellan) and Crataegus flavonoids in hyperlipidemic rats

Both edible fungal polysaccharides (Auricularia and Tremellan) and Crataegus flavonoids promote the balance of dyslipidemia, which have a positive biological regulating effect on intestinal flora. In this study, the extraction of water-soluble polysaccharides from Auricularia and Tremellan was investigated and optimized firstly. Polysaccharides and flavonoids were then combined to study the effects on the mediating role of abnormal blood lipid concentration and intestinal flora in vivo. The rats were divided into 10 groups, the NC (normal control), HM (model), PCI (Simvastatin control), PCII (Fenofibrate control), AAP (Auricularia auricular Polysaccharide), TFP (Tremella fuciformis Polysaccharide), HF (Crataegus Flavonoid), LDC (Low-dose combination), MDC (Medium dose combination), and HDC (High-dose combination), used to explore the impact of polysaccharides and flavonoids complex on state of blood lipid, liver, and intestinal flora of dyslipidemia rats. The results showed that the combination of polysaccharides and flavonoids could significantly decrease the levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and increase the level of high-density lipoprotein cholesterol (HDL-C). It also significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and improved liver morphology. What is more, the HDC favorably alters the intestinal microflora balance, promotes intestinal integrity and mobility, and inhibits the growth of harmful bacteria such as Escherichia coli/Shigella and Clostridium compared with HM group. In brief, the combination of polysaccharides and flavonoids had a synergistic effect on the remission of dyslipidemia, and promoted health by improving lipid metabolism, protecting liver tissue, and regulating the intestinal flora in hyperlipidemia rats.

Qing Hua Chang Yin alleviates chronic colitis of mice by protecting intestinal barrier function and improving colonic microflora

Background: Qing Hua Chang Yin (QHCY) is a famous formula of traditional Chinese medicine (TCM) and has been proven to have protective effect on ulcerative colitis. However, its protective effect and potential therapeutic mechanisms in chronic colitis remain unclear. The purpose of this study is to explore the effects and underlying mechanisms of QHCY on dextran sulfate sodium (DSS)-induced chronic colitis mice model. Methods: The chronic colitis model was established by administration of 2% DSS for three consecutive cycles of 7 days with two intervals of 14 days for recovery by drinking water. The experiment lasted 49 days. The DSS + QHCY group received QHCY administration by oral gavage at doses of 1.6 g/kg/d, DSS + Mesalazine group was administrated Mesalazine by oral gavage at doses of 0.2 g/kg/d. The control and DSS group were given equal volume of distilled water. The body weight, stool consistency and blood in stool were monitored every 2 days. The disease activity index (DAI) was calculated. The colon length was measured after the mice were sacrificed. The histomorphology of colonic tissues was checked by the HE and PAS staining. Immunohistochemistry was performed to detect the expressions of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), tight junction proteins (ZO-1, occludin) and Mucin2 (MUC2). 16S rRNA sequencing analysis was conducted to study the diversity and abundance of gut microbiota changes. Results: QHCY treatment not only significantly attenuated DSS-induced the weight loss, DAI score increase, colon shortening and histological damage in mice, but also decreased the expression of pro-inflammatory cytokines in colonic tissues and increased the expression of ZO-1, occludin, and MUC2. Furthermore, QHCY enhanced the diversity of gut microbes and regulated the structure and composition of intestinal microflora in mice with chronic colitis. Conclusion: QHCY has a therapeutic effect on a murine model of chronic colitis. It can effectively reduce the clinical and pathological manifestations of colitis and prevent alterations in the gut microbiota.

Effects of Replacing Soybean Meal Protein with Chlorella vulgaris Powder on the Growth and Intestinal Health of Grass Carp (Ctenopharyngodon idella)

Chlorella vulgaris (C. vulgaris) powder is a novel non-grain single-cell protein with enormous potential to be a protein source. However, it is poorly studied in aquatic animals. The purpose of the present study was to explore the optimum replacement ratio of C. vulgaris powder and the influence of the substitution of soybean meal with C. vulgaris on grass carp (Ctenopharyngodon idella) in terms of growth performance, intestinal integrity and the microbial community. Five isonitrogenous and isolipidic diets were formulated by replacing 0% (SM, containing 30% soybean meal), 25% (X25), 50% (X50), 75% (X75) and 100% (X100) soybean meal with C. vulgaris. The feeding trial period lasted 8 weeks. At the end of the experimental trial, the X50 group showed higher FW, WGR and PER than the SM group (p < 0.05). The feed conversion ratio (FCR) of the X50 group was significantly lower than that of the SM group (p < 0.05). The X50 group showed the highest value of the goblet cell number, intestinal amylase and trypsin activities when compared with the SM group (p < 0.05). Replacing 50% soybean meal with C. vulgaris improved the intestinal barrier integrity, as evidenced by upregulating zo-1, zo-2 and occluding transcript (p < 0.05), and alleviated oxidative stress by an increased SOD enzymatic activity and transcript level, probably mediated through the Nrf2-keap1 signaling pathway (p < 0.05). Meanwhile, the X50 group enhanced intestinal immunity, as manifested by increased ACP and LZM activities (p < 0.05), and downregulated the tlr-4, tlr-7, tlr-8 and il-6 through the tlr pathway (p < 0.05). The functionally predicting pathways related to the nitrate respiration and nitrogen respiration were observably activated in the X50 group (p < 0.05). The X50 group improved the biological barrier, as manifested by increased Firmicutes and Rhodobacter (p < 0.05). In conclusion, dietary C. vulgaris powder could promote the growth performance of grass carp by restoring intestinal morphology, increasing digestive enzyme activities, improving antioxidant properties and immunity and optimizing the microflora structure. A C. vulgaris powder replacement of 50% soybean meal was recommended as feed for grass carp.

How Do Microorganisms Influence the Development of Endometriosis? Participation of Genital, Intestinal and Oral Microbiota in Metabolic Regulation and Immunopathogenesis of Endometriosis

Microorganisms inhabiting the human body play an extremely key role in its proper functioning, as well as in the development of the immune system, which, by maintaining the immune balance, allows you to enjoy health. Dysbiosis of the intestinal microbiota, or in the oral cavity or reproductive tract, understood as a change in the number and diversity of all microorganisms inhabiting them, may correlate with the development of many diseases, including endometriosis, as researchers have emphasized. Endometriosis is an inflammatory, estrogen-dependent gynecological condition defined by the growth of endometrial cells outside the uterine cavity. Deregulation of immune homeostasis resulting from microbiological disorders may generate chronic inflammation, thus creating an environment conducive to the increased adhesion and angiogenesis involved in the development of endometriosis. In addition, research in recent years has implicated bacterial contamination and immune activation, reduced gastrointestinal function by cytokines, altered estrogen metabolism and signaling, and abnormal progenitor and stem cell homeostasis, in the pathogenesis of endometriosis. The aim of this review was to present the influence of intestinal, oral and genital microbiota dysbiosis in the metabolic regulation and immunopathogenesis of endometriosis.

Effects of tea residues-fermented feed on production performance, egg quality, antioxidant capacity, caecal microbiota, and ammonia emissions of laying hens

This study was to assess the effects of tea residues-fermented feed (TR-fermented feed) on production performance, egg quality, serum antioxidant capacity, caecal microbiota, and ammonia emissions of laying hens. A total of 1,296 Lohmann laying hens have randomly distributed four groups with six parallels and fed with diets TR-fermented feed at the rates of 0 (control), 1, 3, and 5%. The inclusion of 1% (TR)-fermented feed resulted in a significant increase in egg-laying rate and average egg weight of birds, and a reduction in the feed-to-egg ratio when compared to the control group (p < 0.05). The addition of 1 and 3% of (TR)-fermented feed significantly improved the Haugh unit of eggs (p < 0.05). The eggshell thickness was observed to increase by almost one-fold upon the inclusion of 3 and 5% (TR)-fermented feed in the basal diet (p < 0.05). The supplementation of 3% (TR)-fermented feed significantly increased the content of methionine, tyrosine, proline, essential amino acids (EAA), alpha linoleic acid (C18:3n6), docosanoic acid (C22:0), docosahexaenoic acid (C22:6n3), twenty-three carbonic acids (C23:0), ditetradecenoic acid (C24:1) and total omega-3 polyunsaturated fatty acids (∑ω-3 PUFA) in the eggs (p < 0.05). The addition of a certain amount of (TR)-fermented feed can enhance the activity of glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD) in chicken serum, and reduce the level of malondialdehyde (MDA) (p < 0.05). The ammonia concentration in the hen house of laying hens in the treatment groups decreased significantly (p < 0.05). Bacteroidetes and Firmicutes, the main phyla in the cecal bacterial community, were differentially abundant in each group, comprising greater than 55 and 33%, respectively. Collectively, this research indicates that (TR)-fermented feed supplementation improves the performance of laying hens and reduces ammonia emissions and can be used in industry-scale layer production.

Combined Drug with Antibacterial Effect Supports the Normal Intestinal Microflora

Widespread use of antibiotics leads to an imbalance of normal intestinal microflora and to the development of multidrug resistance. The problem can be solved by administration of the antibiotics in combination with the drugs that have an immunotropic effect. We studied the effect of the drug containing technologically processed affinity purified antibodies to IFNγ, CD4 receptor, β2-microglobulin of MHC class I, and β2-domain of MHC II combined with antibiotics on the composition of intestinal microflora of pigs and the total number of microbiome resistance genes. Using the methods of NGS sequencing and quantitative PCR, we found that the drug contributes to the maintenance of normal microflora and, consequently, to the symbiotic relationship of the host with microflora, and prevents the reproduction of pathogenic bacterial species. Analysis for the presence of the resistance genes of gastrointestinal microorganisms showed that the drug does not affect the qualitative and quantitative composition of these genes of the intestinal microbiome.

Ether Derivatives of Naringenin and Their Oximes as Factors Modulating Bacterial Adhesion

Because of the close connection between adhesion and many vital cellular functions, the search for new compounds modulating the adhesion of bacteria belonging to the intestinal microbiota is a great challenge and a clinical need. Based on our previous studies, we discovered that O-lkyl naringenin derivatives and their oximes exhibit antimicrobial activity against antibiotic-resistant pathogens. The current study was aimed at determining the modulatory effect of these compounds on the adhesion of selected representatives of the intestinal microbiota: Escherichia coli, a commensal representative of the intestinal microbiota, and Enterococcus faecalis, a bacterium that naturally colonizes the intestines but has disease-promoting potential. To better reflect the variety of real-life scenarios, we performed these studies using two different intestinal cell lines: the physiologically functioning ("healthy") 3T3-L1 cell line and the disease-mimicking, cancerous HT-29 line. The study was performed in vitro under static and microfluidic conditions generated by the Bioflux system. We detected the modulatory effect of the tested O-alkyl naringenin derivatives on bacterial adhesion, which was dependent on the cell line studied and was more significant for E. coli than for E. faecalis. In addition, it was noticed that this activity was affected by the concentration of the tested compound and its structure (length of the carbon chain). In summary, O-alkyl naringenin derivatives and their oximes possess a promising modulatory effect on the adhesion of selected representatives of the intestinal microbiota.

Ultrasound-assisted glycation and the allergenicity of α-lactalbumin

BACKGROUND

Ultrasound-assisted glycation is a promising method for decreasing the allergenicity of α-lactalbumin (ALA). However, there is a lack of in vivo studies on the allergenicity of ultrasound-assisted glycated ALA. In this study, the effects of the ultrasound-assisted glycation of ALA on the allergenicity and intestinal microflora were characterized using a BALB/c mouse model.

RESULTS

Increased immunoglobulin -G/ immunoglobulin-E (IgG/IgE) and interleukin-4/6 (IL-4/6) secretions, and reduced interferon-γ (IFN-γ) secretions were found in the serum of ALA sensitized and challenged, mice in comparison with a control group. However, there was no significant difference between the mice fed with ultrasound-assisted glycated ALA and the control group. Mice that were sensitized and challenged with ALA showed disrupted intestinal microflora, manifesting in significantly decreased Firmicutes and significantly increased Proteobacteria. It was found that 100ALA-gal could maintain the intestinal microflora of mice in a normal state. Pearson's rank correlation showed that Proteobacteria and Spirochaetota were correlated positively with the IL-4/IL-6 level and were correlated negatively with the expression of IFN-γ. Proteobacteria were also significantly positively correlated with IL-6 and negatively correlated with IFN-γ (P < 0.05).

CONCLUSION

These results suggested that ultrasound-assisted glycation on ALA can maintain the intestinal microflora in a normal state thus balancing the proportion of Th1/Th2 to decrease allergic reaction. © 2022 Society of Chemical Industry.

The Effects of a High-Fat Diet on Inflammatory Bowel Disease

The interactions among diet, intestinal immunity, and microbiota are complex and play contradictory roles in inflammatory bowel disease (IBD). An increasing number of studies has shed light on this field. The intestinal immune balance is disrupted by a high-fat diet (HFD) in several ways, such as impairing the intestinal barrier, influencing immune cells, and altering the gut microbiota. In contrast, a rational diet is thought to maintain intestinal immunity by regulating gut microbiota. In this review, we emphasize the crucial contributions made by an HFD to the gut immune system and microbiota.

Modulation of Fat Deposition-Gut Interactions in Obese Mice by Administrating with Nobiletin

Intestinal microflora is correlated with obesity, metabolic diseases and digestive tract dysfunctions that are closely related to human health. Nobiletin (NOB) is a dietary polymethoxylated flavonoid with protective effects and activities against oxidative stress, inflammation and cardiovascular disorders. However, the effect and molecular mechanism of NOB in regulating white fat deposition have not been explored. In this study, we reported that NOB administration attenuates weight gain and glucose tolerance in mice fed a high-fat diet (HFD). Additionally, NOB administration substantially restored lipid metabolic disorder and repressed the level of genes related to lipid metabolism in HFD-induced obese mice. The sequencing of 16S rRNA genes in fecal samples unveiled that NOB administration reversed HFD-induced intestinal microbiota composition, particularly in the relative abundances of Bacteroidetes and Firmicutes at the phylum and genus level. Furthermore, NOB supplementation significantly improved the indexes of Chao1 and Simpson and implied NOB can improve intestinal flora diversity in HFD-fed mice. Next, we used LEfSe analysis to explore biomarkers presented as a taxon in different groups. Compared to the HFD group, NOB treatment significantly diminished the proportion of Ruminococcaceae, Ruminiclostridium, Intesinimonas, Oscillibacter and Desulfovibrio. Enriched metabolic pathways were predicted by Tax4Fun analysis and demonstrated that the lipid metabolic pathway is higher in the HFD + NOB group. More importantly, the correlation analysis demonstrated that Parabacteroides was significantly positive and Lactobacillus was negatively related to both body weight and inguinal adipose tissue weight. Collectively, our data emphasized that NOB has the potential to attenuate obesity and confirmed a mechanism for gut microbiota that mediated the beneficial effect of NOB.

Intestinal Microflora Altered by Vancomycin Exposure in Early Life Up-regulates Type 2 Innate Lymphocyte and Aggravates Airway Inflammation in Asthmatic Mice

Allergic asthma is a chronic inflammatory disease primarily mediated by Th2 immune mechanisms. Exposure to antibiotics during early life is associated with an increased risk of allergic asthma, although the exact mechanism is not fully understood. In this study, mice were randomly divided into a normal saline control group (NS group), an OVA-induced asthma group (OVA group), a vancomycin treatment control group (VAN.NS group), and a vancomycin treatment the OVA-induced asthma group (VAN.OVA group). The results showed that vancomycin altered dominant species in experimental mice. The phylum level histogram showed that Bacteroides abundance was increased, and Firmicutes abundance was decreased in the OVA group. Airway inflammation and airway hyperresponsiveness (AHR) were aggravated in the vancomycin-exposed group. Enzyme-linked immunosorbent assay (ELISA) showed that the serum levels of IL-5, IL-13, and IL-33 in the OVA group were higher than those in the NS group, especially in the VAN.OVA group. The expression of GATA binding protein-3(GATA3) and retinoid acid receptor-related orphan receptor alpha (RORa) increased in the OVA group, even more so in the VAN.OVA group. Group 2 innate lymphoid cells (ILC2s) in the lung detected by flow cytometry was increased in OVA mice more than those in control mice, with a more remarkable increase in the VAN.OVA. Our results demonstrated that vancomycin used in early life could alter the intestinal microecology of mice, which, in turn, aggravates airway inflammation and upregulate type 2 innate lymphocytes.

Effects of Different Combinations of Sodium Butyrate, Medium-Chain Fatty Acids and Omega-3 Polyunsaturated Fatty Acids on the Reproductive Performance of Sows and Biochemical Parameters, Oxidative Status and Intestinal Health of Their Offspring

The aim of the study was to investigate the comparative effects of different combinations of sodium butyrate (SB), medium-chain fatty acids (MCFAs), and omega-3 polyunsaturated fatty acids (n-3 PUFAs) on the reproductive performances of sows, as well as on the biochemical parameters, oxidative statuses, and intestinal health of the sucking piglets. A total of 30 sows were randomly allocated to five treatments: (1) control diet (CON); (2) CON with 1 g/kg of coated SB and 7.75 g/kg of coated MCFAs (SM); (3) CON with 1 g/kg of coated SB and 68.2 g/kg of coated n-3 PUFAs (SP); (4) CON with 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFAs (MP); (5) CON with 1 g/kg of coated SB, 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFA (SMP). The results showed that sows fed the SP, MP, and SMP diets had shorter weaning-to-estrus intervals than those fed the CON diet (p < 0.01). The piglets in the SM, SP, and MP groups showed higher increases in the plasma catalase and glutathione peroxidase activities than those of the CON group (p < 0.01). The diarrhea incidence of piglets in the SM, SP and SMP groups was lower than that of piglets in the CON group (p < 0.01). Additionally, the addition of SM, SP, MP, and SMP to the sow diets increased the contents of immunoglobulin A, immunoglobulin G, fat, and proteins in the colostrum (p < 0.01), as well as the plasma total superoxide dismutase activities (p < 0.01) in the suckling piglets, whereas it decreased the mRNA expressions of tumor necrosis factor-α, interleukin-1β, and toll-like receptor 4 in the jejunum mucosa of the piglets. The relative abundances of Prevotella, Coprococcus, and Blautia in the colonic digesta of the piglets were increased in the SM group (p < 0.05), and the relative abundances of Faecalibacterium increased in the SMP group (p < 0.05), compared with the CON group. The relative abundances of Collinsella, Blautia, and Bulleidia in the MP group were higher than those in the CON group (p < 0.05). Collectively, dietary combinations of fatty acids with different chain lengths have positive effects on the growth performances and intestinal health of suckling piglets.

Effects of Nutritionally Induced Obesity on Metabolic Pathways of Zebrafish

Human obesity has become a global epidemic that can lead to many metabolic diseases, including insulin resistance, type 2 diabetes, dyslipidemia, hypertension and nonalcoholic fatty liver. The development of obesity is closely associated with excess food intake and energy imbalance, family history, lifestyle, psychology and other factors, but molecular mechanisms underlying the induction and development of obesity remain to be intensively studied under a variety of internal and external pathogenesis conditions. In this study, we generated two obesity models of zebrafish that were treated with a high-fat diet (HFD) or an overfeeding diet (DIO). Both HFD and DIO zebrafish exhibited higher levels of lipid accumulation, fat distribution, microvascular steatosis and ectopic accumulation of lipid droplets in liver and muscle than normal diet (NOD) fish. The comparison of transcriptome sequencing data for the livers of HFD, DIO and NOD groups identified common and specific genes and signaling pathways that are potentially associated with zebrafish obesity induced by HFD and/or DIO. These findings provide clues for further understanding the mechanisms of obesity development and preventing nutritionally induced obesity through targeting the common signaling pathways and biological processes.

Accessing the In Vivo Efficiency of Clinically Isolated Phages against Uropathogenic and Invasive Biofilm-Forming Escherichia coli Strains for Phage Therapy

Escherichia coli is one of the most common members of the intestinal microbiota. Many of its strains are associated with various inflammatory infections, including urinary or gut infections, especially when displaying antibiotic resistance or in patients with suppressed immune systems. According to recent reports, the biofilm-forming potential of E. coli is a crucial factor for its increased resistance against antibiotics. To overcome the limitations of using antibiotics against resistant E. coli strains, the world is turning once more towards bacteriophage therapy, which is becoming a promising candidate amongst the current personalized approaches to target different bacterial infections. Although matured and persistent biofilms pose a serious challenge to phage therapy, they can still become an effective alternative to antibiotic treatment. Here, we assess the efficiency of clinically isolated phages in phage therapy against representative clinical uropathogenic and invasive biofilm-forming E. coli strains. Our results demonstrate that irrespective of host specificity, bacteriophages producing clear plaques with a high burst size, and exhibiting depolymerizing activity, are good candidates against biofilm-producing E. coli pathogens as verified from our in vitro and in vivo experiments using Galleria mellonella where survival was significantly increased for phage-therapy-treated larvae.

Effect of different ways of ingesting orange essential oil on blood immune index and intestinal microflora in mice

BACKGROUND

Studies have found that the addition of plant essential oils to feed had a positive effect on intestinal microflora and immunity in mice. However, the effect of different ways of ingestion of orange essential oil on mice has seldom been reported. In the present study, we investigated the effects of ingestion of orange essential oil by gavage, sniffing and feeding on intestinal microflora and immunity in mice.

RESULTS

The results obtained showed that a low concentration of essential oil feeding significantly increased the spleen index of mice (P < 0.05). The effect of different ways of ingestion on the thymus index, immunoglobulin G and immunoglobulin M of mice was not significant (P > 0.05). High and medium concentrations of essential oil feeding increased the level of interleukin-2 in mice (P < 0.05). H⁺ K⁺ -ATPase activity was significantly increased in mice fed with gavage and different concentrations of essential oil feed compared to the control group (P < 0.05). The analysis of the results of the microflora in the cecum and colon of mice indicated that the medium concentration of essential oil feeding group and the sniffing group significantly changed the structure of the flora and increased the diversity of the intestinal microflora. All three essential oil ingestion methods increased the abundance of Bacteroidetes and Lactobacillus in the intestine of mice.

CONCLUSION

Compared with gavage and feeding, sniffing had a significant effect on immunoglobulins in mice. All the three ingestion methods could affect the intestinal microflora of mice and increase the abundance of Lactobacillus. © 2022 Society of Chemical Industry.

The Effect of the Gut Microbiota on Transplanted Kidney Function

The intestinal microflora is extremely important, not only in the processes of absorption, digestion and biosynthesis of vitamins, but also in shaping the immune and cognitive functions of the human body. Several studies demonstrate a correlation between microbiota composition and such events as graft rejection, kidney interstitial fibrosis, urinary tract infections, and diarrhoea or graft tolerance. Some of those changes might be directly linked with pathologies such as colonization with pathogenic bacterial strains. Gut microbiota composition also plays an important role in metabolic complications and viral infections after transplantation. From the other side, gut microbiota might induce graft tolerance by promotion of T and B regulatory cells. Graft tolerance induction is still an extremely important issue regarding transplantology and might allow the reduction or even avoidance of immunosuppressive treatment. Although there is a rising evidence of the pivotal role of gut microbiota in aspects of kidney transplantation there is still a lack of knowledge on the direct mechanisms of microbiota action. Furthermore, some of those negative effects could be reversed by probiotics of faecal microbiota trapoinsplantation. While diabetes and hypertension as well as BKV and CMV viremia are common and important complications of transplantation, both worsening the graft function and causing systemic injuries, it opens up potential clinical treatment options. As has been also suggested in the current review, some bacterial subsets exhibit protective properties. However, currently, there is a lack of evidence on pro- and prebiotic supplementation in kidney transplant patients. In the current review, we describe the effect of the microbiota on the transplanted kidney in renal transplant recipients.

Effects of Glyceryl Monolaurate on Production Performance, Egg Quality, Oviduct Cytokines and Intestinal Microflora of 66 Weeks Old Laying Hens

The principal purpose of this research was to study the effects of glycerol monolaurate (GML) on the production performance; egg quality; health state of the oviduct, ovary and ileum; and gut microbiota of laying hens in the later stage. The laying hens were randomly assigned to two groups: a control group and an experiment group, for which 1000 mg/kg of GML was added to a control diet. The results showed that GML increased the laying rate, average egg weight, albumen height, yolk color and Haugh unit and decreased the feed conversion ratio and defective eggs (p < 0.05). GML increased the intestinal villi height and the ratio of villus height to crypt depth (p < 0.05). Moreover, GML improved the contents of cytokines in the oviduct, ovary and ileum mucosa; ameliorated the expression of TLR2, TLR4, MyD88, IL-4, IL-1β and TNF-α; and increased the expression of Occludin and Muc-2 in the ileal mucosa. The supplementation of GML increased the volatile fatty acids in the cecal contents, such as acetic acid and propionic acid, and up-regulated Bacteroides (p < 0.01) and Alistipes (p < 0.05) richness in the cecal contents. In summary, GML improved production performance, egg quality and immunity; ameliorated the health status of the oviduct, ovary and ileum; enhanced the intestinal barrier function; improved the content of intestinal volatile fatty acids; and regulated the abundance of cecal flora.

Ginsenoside Rg3 treats acute radiation proctitis through the TLR4/MyD88/NF-κB pathway and regulation of intestinal flora

Objectives

This study aimed to investigate the protective effect of ginsenoside Rg3 (GRg3) against acute radiation proctitis (ARP) in rats.

Methods

Wistar rats were randomly divided into control, model, dexamethasone-positive, GRg3 low-dose, GRg3 medium-dose, and GRg3 high-dose groups. The ARP rat model was established by a single 22-Gy irradiation of 6 MV) X-rays. The distribution and function of intestinal flora were detected using 16S rRNA high-throughput sequencing, rectal tissue was observed by hematoxylin and eosin (H&E) staining, the expression of interleukin 1β (IL-1β) and IL-10 inflammatory factors was detected by ELISA, and mRNA and protein expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were detected by RT-qPCR and Western blotting, respectively.

Results

GRg3 improved the symptoms of ARP in rats in a dose-dependent manner. The species distribution of intestinal flora in GRg3 rats was significantly different from that in ARP rats. These differences were more significant in the high-dose group, where the numbers of Ruminococcus, Lactobacillus, and other beneficial bacteria were significantly increased, whereas those of Escherichia, Alloprevotella, and other harmful bacteria were decreased. In addition, GRg3 was closely related to amino acid metabolism. After GRg3 treatment, the mRNA and protein expression of TLR4, MyD88, and NF-κB in rectal tissue was significantly down-regulated, and the level of downstream inflammatory factor IL-1β decreased, whereas that of IL-10 increased.

Conclusion

Our study indicated GRg3 as a new compound for the treatment of ARP by inhibiting the TLR4/MyD88/NF-κB pathway, down-regulating the expression of proinflammatory factors, thus effectively regulating intestinal flora and reducing inflammatory reactions.

The Influences and Mechanisms of High-altitude Hypoxia Exposure on Drug Metabolism

BACKGROUND

The special environment of high-altitude hypoxia not only changes the physiological state of the body but also affects the metabolic process of many drugs, which may affect the safety and efficacy of these drugs. The number of drugs is huge, so it is not wise to blindly repeat the pharmacokinetic studies of all of them on the plateau. Mastering the law of drug metabolism on the plateau is conducive to the comprehensive development of rational drug use on the plateau. Therefore, it is very important to determine the impacts and elucidate the mechanism of drug metabolism in hypobaric hypoxia conditions.

METHODS

In this review, we searched published studies on changes in drug metabolism in hypoxia conditions to summarize and analyze the mechanisms by which hypoxia alters drug metabolism.

RESULTS

Although the reported effects of high-altitude hypoxia on drug metabolism are sometimes controversial, metabolism kinetics for most of the tested drugs are found to be affected. Mechanism studies showed that the major reasons causing metabolism changes are: regulated drug-metabolizing enzymes expression and activity mediated by HIF-1, nuclear receptors and inflammatory cytokines, and change in direct or indirect effects of intestinal microflora on drug metabolism by itself or the host mediated by microflora-derived drug-metabolizing enzymes, metabolites, and immunoregulation.

CONCLUSION

Altered enzyme expression and activity in the liver and altered intestinal microflora are the two major reasons to cause altered drug metabolism in hypoxia conditions.

How autophagy, a potential therapeutic target, regulates intestinal inflammation

Inflammatory bowel disease (IBD) is a group of disorders that cause chronic inflammation in the intestines, with the primary types including ulcerative colitis and Crohn's disease. The link between autophagy, a catabolic mechanism in which cells clear protein aggregates and damaged organelles, and intestinal health has been widely studied. Experimental animal studies and human clinical studies have revealed that autophagy is pivotal for intestinal homeostasis maintenance, gut ecology regulation and other aspects. However, few articles have summarized and discussed the pathways by which autophagy improves or exacerbates IBD. Here, we review how autophagy alleviates IBD through the specific genes (e.g., ATG16L1, IRGM, NOD2 and LRRK2), crosstalk of multiple phenotypes with autophagy (e.g., Interaction of autophagy with endoplasmic reticulum stress, intestinal antimicrobial defense and apoptosis) and autophagy-associated signaling pathways. Moreover, we briefly discuss the role of autophagy in colorectal cancer and current status of autophagy-based drug research for IBD. It should be emphasized that autophagy has cell-specific and environment-specific effects on the gut. One of the problems of IBD research is to understand how autophagy plays a role in intestinal tract under specific environmental factors. A better understanding of the mechanism of autophagy in the occurrence and progression of IBD will provide references for the development of therapeutic drugs and disease management for IBD in the future.

The Effects of Black Tea Consumption on Intestinal Microflora-A Randomized Single-Blind Parallel-Group, Placebo-Controlled Study

We previously reported that black tea consumption for 12 wk reduced the risk of acute upper respiratory tract inflammation, and improved secretory capacity in individuals with low salivary SIgA levels (Tanaka Y et al. 2021. Jpn Pharmacol Ther 49: 273-288). These results suggested that habitual black tea consumption improves mucosal immunity. Therefore, in this study we evaluated the effect of black tea intake on gut microbiota, which is known to be involved in mucosal immunity, by analyzing the bacterial flora and the short-chain fatty acids (SCFAs) concentration of feces collected during the above clinical study. The clinical design was a randomized, single-blind, parallel-group, placebo-controlled study with 72 healthy Japanese adult males and females, who consumed three cups of black tea (Black Tea Polymerized Polyphenols 76.2 mg per day) or placebo per day for 12 wk. In all subjects intake of black tea significantly increased abundance of Prevotella and decreased fecal acetic acid concentration. Particularly in the subjects with low salivary SIgA levels, the change over time of total bacteria, Prevotella, and butyrate-producing bacteria, which are involved in normalizing immune function, were higher in the black tea group than in the placebo group. In subjects with low abundance of Flavonifractor plautii a butyrate-producing bacteria, black tea consumption significantly increased salivary SIgA concentration and the absolute number of Flavonifractor plautii. In conclusion, our results suggest that improvement of mucosal immunity via an increase in butyrate-producing bacteria in the gut may partly contribute to the suppressive effect of black tea consumption on acute upper respiratory tract inflammation observed in our previous report.

Interactive effects of dietary supplementation between illite and probiotic on productive performance, intestinal microflora, and blood profiles of laying hens

This study investigates the interactive effects of dietary illite and probiotic on productive performance, intestinal microflora, and blood profiles of laying hens. A total of 432 laying hens at 24 weeks old were allotted into six dietary groups. An experimental design was composed with a 3 (illite levels: 0, 0.3, and 0.6%) × 2 (probiotic levels: 0 and 0.2%). The probiotic based on Bacillus subtilis, Saccharomyces cerevisiae, and B. licheniformis was used. There were interactions between illite and probiotic on total microbes and salmonella of digesta. Higher egg production was observed in hens fed a diet supplemented with either 0.6% illite or 0.2% probiotic than in those fed a basal diet. The total microbes of the group fed a diet with 0.6% illite were lower than the groups fed diets with 0 and 0.3% illite. A lower number of Escherichia coli was observed in hens fed a diet with probiotic than those fed a basal diet. Higher immunoglobulin G concentration was observed in the group fed a diet supplemented with 0.6% illite than in those fed a basal diet. Our results suggest illite and probiotic can be used as feed additives for hens, separately or in combination to improve performance and intestinal microflora.

Exploring the regulatory mechanism of osteoporosis based on intestinal flora: A review

Osteoporosis is 1 of the common diseases of bone metabolism in clinic. With the aging of the population in China, osteoporosis is becoming more and more serious, and it has become 1 of the major public health problems. However, traditional therapies, such as calcium therapy and estrogen therapy, can cause serious adverse effects and damage to the body when ingested over a long period of time. Therefore, there is an urgent need to explore alternative therapies with less side effects in clinical practice. Intestinal flora is a hot topic of research in recent years. It has been studied in inflammatory bowel disease, diabetes, depression and so on. Recently, intestinal flora has received increasing attention in the pathways regulating bone metabolism. This paper contains a review of recent studies related to osteoporosis and gut flora in terms of its metabolites, immune, endocrine, and brain-gut axis pathways. The strong association between intestinal flora and bone metabolism suggests, to some extent, that intestinal flora can be a potential target for osteoporosis prevention and treatment, providing new ideas and therapies for the prevention and treatment of osteoporosis.

Effects of the Radix Ginseng and Semen Ziziphi Spinosae drug pair on the GLU/GABA-GLN metabolic cycle and the intestinal microflora of insomniac rats based on the brain-gut axis

Introduction: To explore the mechanism of action of appling Radix Ginseng and Semen Ziziphi Spinosae Drug pair (R-S) in the treatment of insomnia by investigating the effect of R-S on GLU/GABA-GLN metabolic cycle and intestinal microflora of rats with insomnia. Methods: Rats were intraperitoneally injected with 4-chloro-DL-phenylalanine (PCPA) to make sleep deprivation (SD) models. The rats were divided into 6 groups, with 8 rats in each group. The general status of the rats was observed and the pentobarbital sodium sleep synergy experiment was performed. The contents of GABA, GLU, GLN, GAD65, and GS in hippocampus of rats were determined by ELISA. The expressions of GABAARα1mRNA, mGluR5mRNA, NR1mRNA and GluR1mRNA in rats' hippocampal tissue were determined by Realtime PCR. 16SrRNA gene sequencing was used to analyze the intestinal microflora of insomnia rats. Results: In PCPA-induced insomnia rats, the state of insomnia was relieved, the sleep rate was improved, the duration of sleep latency was shortened and the sleep duration was prolonged in each dose group of R-S (p < 0.05, p < 0.01) compared with the model group. The contents of GABA, GLN, GAD65 and GS were increased (p < 0.05, p < 0.01) while GLU content was decreased (p < 0.01) in both medium and high dose groups, especially in the high dose group. The expression of GABAARα1mRNA was increased (p < 0.01), and the expressions of mGluR5mRNA, NR1mRNA and GluR1mRNA were decreased (p < 0.01) in hippocampal tissue of rats in R-S groups, especially in the high dose group. At the same time, the various dose groups of R-S could improve the species diversity, microflora abundance of insomnia rats and regulate the KEGG metabolic pathway related to sleep. Discussion: R-S can improve the sleep of PCPA-induced insomnia rats by regulating GLU/GABA-GLN metabolic cycle and intestinal microflora, which provides experimental basis for appling R-S in the treatment of insomnia.

Intestinal Microflora Characteristics of Antheraea pernyi (Lepidoptera: Saturniidae) Larvae With Vomit Disease

Antheraea pernyi Guérin-Méneville (Lepidoptera: Saturniidae) is of high economic value as a source of silk, food, and bioactive substances with medicinal properties. A. pernyi larvae are prone to A. pernyi vomit disease (AVD), which results in substantial economic losses during cultivation; however, the relationship between AVD and A. pernyi gut microbiota remains unclear. Here, we investigated the bacterial community in the midgut and feces of A. pernyi larvae with and without AVD using 16S rRNA gene sequencing with Illumina MiSeq technology. Compared with healthy larvae, intestinal bacterial diversity and community richness increased and decreased in larvae with mild and severe AVD, respectively. In addition, the proportion of gut Enterobacter Hormaeche and Edwards(Enterobacteriales: Enterobacteriaceae) and Enterococcus Thiercelin and Jouhaud (Lactobacillales: Enterococcaceae) was higher and lower, respectively, in larvae with mild AVD than those in healthy larvae. A. pernyi vomit disease infection significantly increased the genera with abundance <1%. In the gut of larvae with severe AVD, the proportion of Turicibacter Bosshard et al. (Erysipelotrichales: Turicibacteraceae) increased significantly to 81.53-99.92%, whereas that of Enterobacter decreased compared with healthy larvae. However, the diversity of fecal bacteria was similar between healthy larvae and those with mild AVD. Overall, the findings demonstrate that intestinal microflora in A. pernyi larvae are altered by AVD infection and may cause secondary bacterial infection. This is the first report of the presence of Turicibacter in the intestinal tract of lepidopterans.

The relationship between Alzheimer's disease and intestinal microflora structure and inflammatory factors

To analyze the structural characteristics of intestinal microflora and changes of serum inflammatory factors of the Alzheimer's disease, and to explore the relationship between them and dementia, we selected 30 patients in the AD group and 30 patients in the normal group, and collected stool samples to analyze the intestinal flora structure characteristics of the two groups of patients, and statistically analyzed the inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-8 by ELISA from the venous blood of the two groups. The results show that the dominant Bacteroides in the two groups are Bacteroides, Firmicutes, Proteobacteria, and Actinobacteria. The abundance of Bacteroides, Firmicutes, and Proteobacteria in the AD group shows a statistical difference. At the genus level, the abundance of anti-inflammatory bacteria such as Lactobacillus, Bifidobacterium, and Ruminococcus drops in AD group, while the abundance of pro-inflammatory bacteria such as Escherichia and Enterococcus raises. Statistical analysis of inflammatory cytokines in the two groups suggests that TNF-α and IL-6 levels significantly increase in the AD group, with statistical differences. Therefore, it is speculated that the increased abundance of pro-inflammatory bacteria in intestinal flora may lead to or aggravate neuroinflammation through the release of inflammatory factors, thus further leading to the occurrence and development of AD.

Exploring the therapeutic mechanism of Baduanjin in the treatment of elderly stable angina pectoris based on the gut microbiota-lipid metabolism spectrum: Study protocol for a randomized controlled trial

Importance

Stable angina pectoris (SAP) often occurs in the elderly and is relatively stable for 1-3 months; however, if patients do not receive effective treatment, life-threatening acute myocardial infarction could occur. Patients with different clinical types of coronary heart disease have different intestinal flora. Baduanjin, a traditional Chinese Qigong, has been used as adjuvant therapy to improve the symptoms of patients with SAP.

Objective

To determine the effect of Baduanjin exercise on the symptoms of patients with SAP and the intestinal flora, explore the action links and targets of Baduanjin intervention in elderly patients with SAP, and explain its mechanism.

Design

A single-center, single-blind, randomized controlled trial. Patients and outcome assessors were blinded to group allocation.

Setting

The trial will be conducted at Guang'anmen Hospital of China Academy of Chinese Medical Sciences.

Participants

One hundred and eighty patients aged 60 to 80 years with stable angina pectoris (I-III) were intervened for 8 weeks and followed up for half a year.

Interventions

Among the screened patients, 180 patients will be randomly assigned to either the Baduanjin or the control group at a 1:1 ratio (exercise duration: for 3-5 times a week, for 8 weeks) of moderate-intensity Baduanjin or free activities.

Main and secondary results

The main result is the total effective rate for angina pectoris symptoms; secondary results include the duration of angina pectoris, number of angina pectoris episodes per week, nitroglycerin consumption, nitroglycerin reduction rate, Seattle angina score (SAQ), quality of life (SF-36),Traditional Chinese Medicine (TCM) syndrome scores, electrocardiogram (ECG) changes, blood lipid serum hypersensitive C-reactive protein levels, intestinal flora changes, serum changes in the intestinal flora metabolite Trimetlylamine oxide (TMAO), and non-targeted liposome detection. Adverse events will be recorded throughout the experiment, and the data will be analyzed by researchers who did not know about the assignment.

Discussion

This study provides compelling evidence for at-home use of Baduanjin exercise to relieve SAP-associated symptoms.

Trial registration

This study was approved by the ethics committee of Guang'anmen Hospital of China Academy of Chinese Medical Sciences (2022-121-KY). The trial has been registered in Chinese Clinical Trial Registration Center (ChiCTR2200062450).

The Structural Characterization and Immunomodulatory Activity of Polysaccharides from Pleurotus abieticola Fruiting Bodies

Polysaccharides obtained from mushrooms have been reported to possess immunomodulatory properties. In this study, a water-soluble polysaccharide was purified from the fruiting bodies of Pleurotus abieticola, entitled PAPS1. After its composition and structural analysis, the immunomodulatory activity was investigated in immunosuppressed mice induced by cyclophosphamide (CTX) at a dosage of 70 mg/kg by intraperitoneal injection for 7 days. After 28 days of intragastric administration, PAPS1 alleviated cyclophosphamide (CTX)-induced histopathological damage and increased the expressions of splenic CD4, CD8, CD56 and IgM in the serums of immunosuppressed mice. PAPS1 suppressed the oxidative stress indicated by preventing the increases in ROS and MDA levels. According to the intestinal microflora analysis, PAPS1 regulated 11 bacteria at the gene level, including Helicobacter and Paraprevotella, which are related to immunity and oxidative capacity. Compared with CTX-treated mice, significant increases in immune-related cytokines, such as interleukin (IL)-2, IL-6 and IL-12 in the serums of mice treated with PAPS1, were observed. Finally, PAPS1 can strongly increase the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream proteins. In conclusion, PAPS1-boosted immunity may be related to its suppression on oxidative stress via enhancing the activity of Nrf2 signaling. Thus, PAPS1 can be investigated as a candidate for immunomodulatory therapy.

Evaluation of DDGS as a Low-Cost Feed Ingredient for Common Carp (Cyprinus carpio Linneus) Cultivated in a Semi-Intensive System

Distillers dried grains with solubles (DDGS), a coproduct from the ethanol production industry, is successfully used as an ingredient in feeding cattle and pigs due to its relatively high protein and nutrient content and low price compared to cereals. The aim of this study was to establish the optimal DDGS concentration that can be included in the diet of common carp. A seven-week experiment was performed on common carp with an initial weight of 86 g feed with three experimental diets D0 (DDGS 0%), D1 (DDGS 25%) and D2 (DDGS 35%). The chemical composition of DDGS analyzed by Fourier Transform Near-Infrared (FT-NIR) spectroscopy showed a protein content of 27.56% and oil at 6.75%. Diets with DDGS did not produce significant changes in growth parameters, flesh quality, and blood biochemical profile. Regarding the oxidative status in the muscle tissue, D1 and D2 significantly reduced, in a dose-dependent manner, the specific activity of SOD and GSH, while CAT and GPX were left unaffected. In the liver tissue, CAT, GSH, MDA and carbonylated proteins were reduced in the DDGS diets. The microbiological analysis of the intestinal contents revealed a variation in microbial density depending on the diet used. The total number of aerobic germs was between 224.2 × 104 and 69.84 × 106 (D2 > D1 > D0) and the total number of anaerobic germs was between 15.2 × 102 and 28.2 × 102 (D2 > D0 > D1).

Toxicity Analysis of Mesoporous Polydopamine on Intestinal Tissue and Microflora

As a promising therapy, photothermal therapy (PTT) converts near-infrared (NIR) light into heat through efficient photothermal agents (PTAs), causing a rapid increase in local temperature. Considering the importance of PTAs in the clinical application of PTT, the safety of PTAs should be carefully evaluated before their widespread use. As a promising PTA, mesoporous polydopamine (MPDA) was studied for its clinical applications for tumor photothermal therapy and drug delivery. Given the important role that intestinal microflora plays in health, the impacts of MPDA on the intestine and on intestinal microflora were systematically evaluated in this study. Through biological and animal experiments, it was found that MPDA exhibited excellent biocompatibility, in vitro and in vivo. Moreover, 16S rRNA analysis demonstrated that there was no obvious difference in the composition and classification of intestinal microflora between different drug delivery groups and the control group. The results provided new evidence that MPDA was safe to use in large doses via different drug delivery means, and this lays the foundation for further clinical applications.

Phosphorus Nutrition in Songpu Mirror Carp (Cyprinus carpio Songpu) During Chronic Carbonate Alkalinity Stress: Effects on Growth, Intestinal Immunity, Physical Barrier Function, and Intestinal Microflora

Carbonate alkalinity is a major environmental stress factor affecting aquatic feed configuration, which easily causes oxidative stress and hypoimmunity for fish. Hence, the purpose of the study is to assess the potential effect of phosphorus on growth, intestinal oxidation resistance, physical barrier function, and microflora for Songpu mirror carp (Cyprinus carpio Songpu) (initial average weight of 2.95 ± 0.21 g) reared at the high-concentration carbonate alkalinity environment. A two-factor, three-level (2 × 3) design was applied, in which diets with three different phosphorus levels (3.6, 7.0, and 10.5 g/kg dry matter) were randomly assigned to 0 and 15 mmol/L carbonate alkalinity groups with three replicate aquariums. After the 8-week trial, we found that weight gain rate (WGR), specific growth rate (SGR), protein efficiency ratio (PER), and lipase and amylase activities in the intestine significantly (p < 0.05) declined with increasing carbonate alkalinity. Carbonate alkalinity of 15 mmol/L significantly reduced glutathione peroxidase (GSHPx) activities in the intestine (p < 0.05). The relative expressions of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), glutathione peroxidase 1a (GPX1a), Clautin3, Clautin11, and tumor necrosis factor β (TNF-β) in the intestine were markedly downregulated by increasing carbonate alkalinity levels (p < 0.05), whilst the relative expressions of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) in the intestine were markedly upregulated (p < 0.05). At the 15 mmol/L carbonate alkalinity treatment, Songpu mirror carp suffer from hypoimmunity status with failed digestion, antioxidant, inflammation, and immune response, thereby inducing impaired growth. Additionally, significant increments in the abundance of Proteobacteria and a significant decrease in the abundance of Fusobacteria and the Firmicutes/Bacteroidetes ratio were caused due to excessively high carbonate alkalinity (15 mmol/L) and excessively low dietary phosphorus supply (3.6 g/kg). Collectively, 7.0 g/kg dietary phosphorus supplementation was effective in promoting intestinal antioxidant enzyme activities and the corresponding gene expression via the Keap1-Nrf2 signaling pathway and in enhancing intestinal immunity by upregulating anti-inflammatory and downregulating pro-inflammatory genes. Appropriate dietary phosphorus supply could promote the formation of beneficial microflora in freshwater, and it has the potential ability to transfer the adverse effect of carbonate alkalinity stress to the structural composition of intestinal microflora. Hence, consideration should be given to suitable phosphorus supply for fish under the chronic carbonate alkalinity stress.

Lactobacillus casei SYF-08 Protects Against Pb-Induced Injury in Young Mice by Regulating Bile Acid Metabolism and Increasing Pb Excretion

Pb poisoning affects infant growth and development. However, dimercaptosuccinic acid (DMSA) as the current therapy for Pb poisoning exerts relatively significant toxic side effects in infants. Therefore, identifying a non-toxic treatment in this regard is particularly important. In this study, we aimed to investigate the therapeutic effect of an infant feces-derived probiotic strain, Lactobacillus casei SYF-08 (SYF-08), on Pb poisoning in young mice. The Pb levels in the organisms were detected via inductively coupled plasma mass spectrometry, while the therapeutic effect of SYF-08 on Pb-induced neural system damage was explored via the Morris water maze test, hematoxylin-eosin staining, and immunohistochemistry. Additionally, the molecular mechanisms underlying the protective effects of SYF-08 against Pb-induced intestinal damage were also explored via histological staining, 16S rRNA sequencing, untargeted metabolomics, qRT-PCR, and western blotting. In vivo experiments revealed that SYF-08 reduced blood and bone Pb levels and increased urinary Pb excretion. Additionally, SYF-08 alleviated Pb-induced pathological damage to the brain and ultimately improved the learning and cognitive abilities of the young mice. This treatment also restored intestinal microflora dysbiosis, regulated bile acid metabolism, and inhibited the FXR-NLRP3 signaling pathway. It also resulted in fewer adverse events than the DMSA treatment. In conclusion, our results provided valuable insights into the therapeutic role of SYF-08 in Pb poisoning and also suggested that its administration can significantly alleviate the Pb-induced damage.