Lactobacillus derived from breast milk facilitate intestinal development in IUGR rats

Changes of intestinal microbiome and its relationship with painful diabetic neuropathy in rats

OBJECTIVE

To analyze the gut bacterial microbiome in rats with painful diabetic neuropathy (PDN) compared to normal rats.

METHODS

Type 2 diabetes was induced in rats via a high-fat and high-sugar diet combined with a low dose of streptozotocin. Glucose metabolism and insulin sensitivity were evaluated using intraperitoneal glucose tolerance tests and insulin tolerance tests. The progression of peripheral neuropathy was assessed using the mechanical withdrawal threshold and thermal withdrawal latency. Histopathological analysis of rat colon tissues was performed using hematoxylin-eosin staining to observe morphological changes. The expression levels of pro-inflammatory cytokines TNF-α and IL-1β in spinal cord tissues were measured using enzyme-linked immunosorbent assay (ELISA). Fecal samples were then collected for metagenomic sequencing and analysis.

RESULT

Behavioral tests revealed reduced mechanical withdrawal threshold and thermal withdrawal latency in PDN rats. Histological analysis showed significant colonic mucosal damage and inflammatory cell infiltration, suggesting impaired intestinal barrier function. Elevated TNF-α and IL-1β levels in spinal cord tissues further highlight peripheral inflammation's role in PDN. Sequencing analysis revealed significant differences in gut microbiota composition between PDN and control rats, with altered Bacillota/Bacteroidota ratios and increased Lactobacillus abundance. Functional annotation analysis, based on the KEGG, EggNOG, and CAZy databases, indicated significant enrichment of metabolic pathways related to carbohydrate and amino acid metabolism, energy metabolism, and cell structure biogenesis in PDN rats. Cluster analysis identified higher functional clustering in Metabolism and Genetic Information Processing pathways in PDN rats.

CONCLUSION

This study demonstrates that PDN leads to altered gut microbiota composition, disrupted metabolic pathways, and increased inflammation, contributing to the pathological progression of diabetic neuropathy. This study provides new insights into the interplay between gut microbiota and diabetic neuropathy, offering potential avenues for therapeutic interventions targeting microbiome and metabolism.

Gut dysbiosis conveys psychological stress to activate LRP5/β-catenin pathway promoting cancer stemness

Psychological stress causes gut microbial dysbiosis and cancer progression, yet how gut microbiota determines psychological stress-induced tumor development remains unclear. Here we showed that psychological stress promotes breast tumor growth and cancer stemness, an outcome that depends on gut microbiota in germ-free and antibiotic-treated mice. Metagenomic and metabolomic analyses revealed that psychological stress markedly alters the composition and abundance of gut microbiota, especially Akkermansia muciniphila (A. muciniphila), and decreases short-chain fatty acid butyrate. Supplement of active A. muciniphila, butyrate or a butyrate-producing high fiber diet dramatically reversed the oncogenic property and anxiety-like behavior of psychological stress in a murine spontaneous tumor model or an orthotopic tumor model. Mechanistically, RNA sequencing analysis screened out that butyrate decreases LRP5 expression to block the activation of Wnt/β-catenin signaling pathway, dampening breast cancer stemness. Moreover, butyrate as a HDAC inhibitor elevated histone H3K9 acetylation level to transcriptionally activate ZFP36, which further accelerates LRP5 mRNA decay by binding adenine uridine-rich (AU-rich) elements of LRP5 transcript. Clinically, fecal A. muciniphila and serum butyrate were inversely correlated with tumoral LRP5/β-catenin expression, poor prognosis and negative mood in breast cancer patients. Altogether, our findings uncover a microbiota-dependent mechanism of psychological stress-triggered cancer stemness, and provide both clinical biomarkers and potential therapeutic avenues for cancer patients undergoing psychological stress.

Gut Microbiota, Inflammation, and Probiotic Supplementation in Fetal Growth Restriction-A Comprehensive Review of Human and Animal Studies

Fetal growth restriction (FGR) is a pathological state that represents a fetus's inability to achieve adequate growth during pregnancy. Several maternal, placental, and fetal factors are likely associated with FGR etiology. FGR is linked to severe fetal and neonatal complications, as well as adverse health consequences in adulthood. Numerous randomized controlled trials (RCTs) have demonstrated improved growth in FGR fetuses with promising treatment strategies such as maternal micronutrient, amino acid, and nitric oxide supplementation. Elevated inflammation in pregnant women diagnosed with FGR has been associated with an imbalance between pro- and anti-inflammatory cytokines. Gut microbiota dysbiosis may result in increased FGR-related inflammation. Probiotic treatment may relieve FGR-induced inflammation and improve fetal growth. The aim of this review is to provide an overview of the gut microbiota and inflammatory profiles associated with FGR and explore the potential of probiotics in treating FGR.