双歧杆菌对应激大鼠肠道菌群及促肾上腺皮质激素释放激素的影响

Pediatric allergic rhinitis with functional gastrointestinal disease: Associations with the intestinal microbiota and gastrointestinal peptides and therapeutic effects of interventions

Children are susceptible to allergic rhinitis (caused by external allergens) accompanied by functional gastrointestinal disease, which seriously affects physical and mental health. Antihistamines and nasal spray hormones are commonly used in clinical treatment, but these drugs often have unsatisfactory efficacy and result in high recurrence rates. Therefore, understanding the pathogenesis of allergic rhinitis with functional gastrointestinal disease and seeking safer treatment and prevention methods is essential. Herein, molecular ecology and immunoassays were used to analyze correlations between pediatric allergic rhinitis with functional gastrointestinal disease and both the intestinal microbiota and gastrointestinal peptide levels. Fifty healthy children (healthy group) and 80 children with allergic rhinitis with functional gastrointestinal disease (case group: evenly divided into a control group (conventional drug therapy) and an intervention group (conventional drug therapy + glutamine+probiotics)), were enrolled. Bifidobacterium and Lactobacillus counts and the gastrin and motilin levels were lower in the case group than in the healthy group, whereas Enterobacter, yeast, and Enterococcus counts and the somatostatin, serotonin, and vasoactive intestinal peptide levels were higher. Post treatment, intestinal microbiota indices, gastrointestinal peptide levels, and intestinal barrier function were better in the intervention group than in the control group (p < 0.05). The intervention group had a significantly higher total therapeutic response rate (95.00%) than the control group (77.50%). The intestinal microbiota was closely associated with gastrointestinal peptide levels. Treatment with glutamine and probiotics regulated these levels, re-established balance in the intestinal microbiota, and restored intestinal barrier function.

Effects of Myeloid Hif-1β Deletion on the Intestinal Microbiota in Mice under Environmental Hypoxia

External environmental factors can cause an imbalance in intestinal flora. For people living in the extremes of a plateau climate, lack of oxygen is a primary health challenge that leads to a series of reactions. We wondered how intestinal microorganisms might change in a simulated plateau environment and what changes might occur in the host organism and intestinal microorganisms in the absence of hypoxia-related factors. In this study, mice carrying a knockout of hypoxia-inducible factor 1β (Hif-1β) in myeloid cells and wild-type mice were raised in a composite hypoxic chamber to simulate a plateau environment at 5,000 m of elevation for 14 days. The mice carrying the myeloid Hif-1β deletion displayed aggravated hypoxic phenotypes in comparison to and significantly greater weight loss and significantly higher cardiac index values than the wild-type group. The levels of some cytokines increased in the hypoxic environment. Analysis of 16S rRNA sequencing results showed that hypoxia had a significant effect on the gut microbiota in both wild-type and Hif-1β-deficient mice, especially on the first day. The levels of members of the Bacteroidaceae family increased continuously from day 1 to day 14 in Hif-1β deletion mice, and they represented an obviously different group of bacteria at day 14 compared with the wild-type mice. Butyrate-producing bacteria, such as Butyricicoccus, were found in wild-type mice only after 14 days in the hypoxic environment. In conclusion, hypoxia caused heart enlargement, greater weight loss, and obvious microbial imbalance in myeloid Hif-1β-deficient mice. This study revealed genetic and microecological pathways for research on mechanisms of hypoxia.

Protective effect of Bifidobacterial secretory adhesin on intestinal epithelial cells in vitro: a morphological observation

AIM: To observe the effect of Bifidobacterial secretory adhesin on the morphology of human intestinal epithelial cells in vitro.

METHODS: After human intestinal epithelial cells were pretreated with adhesin and then incubated with LPS or H₂O₂, cell morphological changes were observed by light microscopy, electron microscopy and acridine orange staining.

RESULTS: Light microscopic analysis showed that cells became smaller and rounder with abundant granules in the cytoplasm after treatment with LPS or H₂O₂. In addition, some cells shed and floated on culture medium. Acridine orange staining and electron microscopic analysis showed that LPS or H₂O₂ induced the apoptosis of Lovo cells. Ultrastructural changes consist of nuclear condensation, margination and fragmentation of nuclear chromatin. Pretreatment with adhesion significantly improved the above morphological changes and reduced the number of apoptotic cells in cells treated with LPS or H₂O₂.

CONCLUSION: Bifidobacterial adhesin could protect intestinal epithelial cells from LPS- and H₂O₂-induced damage.