Sodium Butyrate Attenuates Taurocholate-Induced Acute Pancreatitis by Maintaining Colonic Barrier and Regulating Gut Microorganisms in Mice

The comprehensive analysis of gut microbiome and spleen transcriptome revealed the immunomodulatory mechanism of Dendrobium officinale leaf polysaccharide on immunosuppressed mice

In recent years, the immunomodulatory efficacy of Dendrobium officinale leaf polysaccharide (DOLP) has attracted much attention, but its potential immunomodulatory mechanism remains unclear. Therefore, we investigated the molecular mechanism of DOLP to ameliorate cyclophosphamide-induced immunosuppressed mice based on transcriptome profiling technology. The results indicated that DOLP significantly mitigated damage to immune organs, regulated the expression levels of inflammatory factors and immunoglobulins, and restored the balance of gut microbiota. Furthermore, it modulated metabolic pathways associated with the immune system, including antigen processing and presentation, hematopoietic cell line development, and natural killer cell-mediated cytotoxicity. DOLP might promote host hematopoietic function to enhance immune cell proliferation and differentiation by up-regulating Cd19, Cr2 and Il7r but down-regulating Dntt. DOLP also up-regulated the expression of MHC-1 (Gm11127, H2-K1, H2-Q10, H2-Q6, and H2-Q7), thus promoting antigen recognition by NK cells to enhance the innate immunity and helping T cells to deliver antigen and secrete immune factors so that enhancing the adaptive immunity.

[Causal relationship between gut microbiota and pigmented villonodular synovitis: a Mendelian randomization analysis]

OBJECTIVE

To investigate the causal relationship between gut microbiota and pigmented villonodular synovitis using Mendelian randomization analysis.

METHODS

We conducted a two-sample Mendelian randomization analysis to investigate the causal relationship between 211 gut microbiome taxa and pigmented villonodular synovitis based on GWAS summary data, with inverse variance weighted (IVW) analysis as the primary result and the other methods as supplementary analyses. The reliability of the results was tested using Cochran's Q test, MR-Egger regression, MR-PRESSO method and conditional Mendelian randomization analysis (cML-MA).

RESULTS

The increased abundance of Barnesiella (OR=3.12, 95% CI: 1.15-8.41, P=0.025) and Rumatococcaceae UCG010 (OR=4.03, 95% CI: 1.19-13.68, P=0.025) may increase the risk of pigmented villous nodular synovitis, and elevated abundance of Lachnospiraceae (OR=0.33, 95% CI: 0.12-0.91, P=0.032), Alistipes (OR=0.16, 95% CI: 0.05-0.53, P=0.003), Blautia (OR=0.20, 95% CI: 0.06-0.61, P=0.005), and Lachnospiraceae FCS020 group (OR=0.38, 95% CI: 0.15-0.94, P=0.036) and Ruminococcaceae UCG014 (OR=0.36, 95% CI: 0.14-0.94, P=0.037) were all associated with a reduced risk of pigmented villonodular synovitis, which were supported by the results of sensitivity analyses. Reverse Mendelian randomization analysis did not reveal any inverse causal association.

CONCLUSION

Increased abundance of specific intestinal microorganisms is associated with increased or decreased risks of developing hyperpigmented villonodular synovitis, and gut microbiota plays an important role in the pathogenesis of this disease.

Acute pancreatitis is associated with gut dysbiosis in children

BACKGROUND

Pediatric acute pancreatitis (AP) is associated with significant morbidity. Therefore, improved understanding of children who will develop severe AP is critical. Adult studies have reported AP associated gut dysbiosis, but pediatric studies are lacking.

AIMS

Assess stool microbial taxonomic and functional profiles of children with first attack of AP compared to those of healthy controls (HC), and between mild and severe AP METHODS: Children under 21 years hospitalized at a tertiary center (n = 30) with first AP attack were recruited including HC (n = 34) from same region. Shotgun metagenomic sequencing was performed on extracted DNA.

RESULTS

Demographics were similar between AP and HC. Alpha diversity (-0.68 ± 0.13, p-value < 0.001), and beta-diversity (R2=0.13, p-value < 0.001) differed, in children with AP compared to HC. Species including R.gnavus, V.parvula, E.faecalis, C.innocuum were enriched in AP. MetaCyc pathways involved in amino acid metabolism and fatty acid beta-oxidation were enriched in AP. Beta-diversity (R2=0.06, p-value = 0.02) differed for severe AP compared to mild AP with enrichment in E.faecalis and C.citroniae.

CONCLUSIONS

Gut dysbiosis occurs in pediatric AP and is associated with AP severity. A multicenter study confirming these findings could pave way for interventional trials manipulating the gut microbiome to mitigate AP severity.

The Interaction of Microbiome and Pancreas in Acute Pancreatitis

Acute pancreatitis (AP) is a common acute abdomen disease characterized by the pathological activation of digestive enzymes and the self-digestion of pancreatic acinar cells. Secondary infection and sepsis are independent prognosticators for AP progression and increased mortality. Accumulating anatomical and epidemiological evidence suggests that the dysbiosis of gut microbiota affects the etiology and severity of AP through intestinal barrier disruption, local or systemic inflammatory response, bacterial translocation, and the regulatory role of microbial metabolites in AP patients and animal models. Recent studies discussing the interactions between gut microbiota and the pancreas have opened new scopes for AP, and new therapeutic interventions that target the bacteria community have received substantial attention. This review concentrates on the alterations of gut microbiota and its roles in modulating gut-pancreas axis in AP. The potential therapies of targeting microbes as well as the major challenges of applying those interventions are explored. We expect to understand the roles of microbes in AP diagnosis and treatment.

Marine Chitosan-Oligosaccharide Ameliorated Plasma Cholesterol in Hypercholesterolemic Hamsters by Modifying the Gut Microflora, Bile Acids, and Short-Chain Fatty Acids

This study evaluated the cholesterol-alleviating effect and underlying mechanisms of chitosan-oligosaccharide (COS) in hypercholesterolemic hamsters. Male hamsters (n = 24) were divided into three groups in a random fashion, and each group was fed one particular diet, namely a non-cholesterol diet (NCD), a high-cholesterol diet (HCD), and an HCD diet substituting 5% of the COS diet for six weeks. Subsequently, alterations in fecal bile acids (BAs), short-chain fatty acids (SCFAs), and gut microflora (GM) were investigated. COS intervention significantly reduced and increased the plasma total cholesterol (TC) and high-density lipoprotein-cholesterol (HDL-C) levels in hypercholesteremic hamsters. Furthermore, Non-HDL-C and total triacylglycerols (TG) levels were also reduced by COS supplementation. Additionally, COS could reduce and increase food intake and fecal SCFAs (acetate), respectively. Moreover, COS had beneficial effects on levels of BAs and GM related to cholesterol metabolism. This study provides novel evidence for the cholesterol-lowering activity of COS.

The Role of Short-Chain Fatty Acids in Acute Pancreatitis

Acute pancreatitis (AP) is a digestive emergency and can develop into a systematic illness. The role of the gut in the progression and deterioration of AP has drawn much attention from researchers, and areas of interest include dysbiosis of the intestinal flora, weakened intestinal barrier function, and bacterial and endotoxin translocation. Short-chain fatty acids (SCFAs), as one of the metabolites of gut microbiota, have been proven to be depleted in AP patients. SCFAs help restore gut homeostasis by rebuilding gut flora, stabilizing the intestinal epithelial barrier, and regulating inflammation. SCFAs can also suppress systematic inflammatory responses, improve the injured pancreas, and prevent and protect other organ dysfunctions. Based on multiple beneficial effects, increasing SCFAs is an essential idea of gut protective treatment in AP. Specific strategies include the direct use of butyrate or indirect supplementation through fiber, pre/pro/synbiotics, or fecal microbiota transplantation as a promising adjective therapy to enteral nutrition.

REL-NPMI: Exploring genotype and phenotype relationship of pancreatitis based on improved normalized point-by-point mutual information

Pancreatitis is a relatively serious disease caused by the self-digestion of trypsin in the pancreas. The generation of diseases is closely related to gene and phenotype information. Generally, gene-phenotype relations are mainly obtained through clinical experiments, but the cost is huge. With the amount of published biomedical literature increasing exponentially, it carries a wealth of disease-related gene and phenotype information. This study provided an effective way to obtain disease-related gene and phenotype information. To our best knowledge, this work first attempted to explore relationships between genotype and phenotype about the pancreatitis from the computational perspective. It mined 6152 genes and 76,753 pairs of genotype and phenotype extracted from the biomedical literature about pancreatitis using text mining. Based on the above 76,753 pairs, the study proposed an improved normalized point-wise mutual information (REL-NPMI) model to optimize gene-phenotype relations related to pancreatitis, and obtained 12,562 gene-phenotype pairs which may be related to pancreatitis. The extracted top 20 results were validated and evaluated. The experimental results show that the method is promising for exploring pancreatitis' molecular mechanism, thus it provides a computational way for studying pancreatitis' disease pathogenesis. Data resources and the Pancreatitis Gene-Phenotype Association Database are available at http://114.116.4.45:8081/and resources are also available at https://github.com/polipoptbe8023/REL-NPMI.git.

Intraluminal oxygen mitigates acute mesenteric ischaemia: a systematic review of methods and outcomes in animal studies

BACKGROUND

Acute Mesenteric Ischaemic (AMI) is a rare condition with significant morbidity and mortality. Many causes of AMI exist, which usually begin with mucosal injury. Onset is insiduous and there is frequent diagnostic delay. Current treatments can only control established injury and prevent propagation, hence new interventions are needed. The prevention and treatment of AMI by intraluminal delivery of oxygen has yet to be investigated in the clinical setting. This article aims to systemically review experimental studies investigating this novel therapy.

METHODS

Following the PRISMA guidelines, searches of PubMed and Ovid MEDLINE databases were performed up to June 2022. Two independent investigators extracted the data.

RESULTS

There were 20 experimental studies, 16 of which used an occlusive ischaemia reperfusion model. Six different formulations were used to deliver intraluminal oxygen, with perflurocarbon being the most common. Studies consistently showed local and systemic benefits. Intraluminal oxygen therapy improved histological severity of mucosal injury in all studies when oxygen was delivered during the ischaemia phase, but could cause harm if given during the reperfusion phase. Improvement was also demonstrated in endpoints assessing intestinal function, biomarkers of intestinal damage, measures of systemic physiological derangement and mortality.

CONCLUSION

Intraluminal oxygenation appears to be an effective treatment for AMI. There remain significant questions regarding optimal timing and delivery formulation before clinical translation of this treatment strategy.

Integrated Bacteria-Fungi Diversity Analysis Reveals the Gut Microbial Changes in Buffalo With Mastitis

The gut microbial community is closely related to mastitis, but studies regarding the influences of mastitis on gut microbiota in buffalo remain scarce. Herein, we characterized the differences in gut bacterial and fungal communities between mastitis-affected and healthy buffalos. Interestingly, although mastitis had no effect on gut bacterial and fungal diversities in the buffalos, some bacterial and fungal taxa were significantly altered. Bacterial and fungal taxonomic analysis showed that the preponderant bacterial phyla (Firmicutes and Bacteroidetes) and fungal phyla (Ascomycota and Basidiomycota) in buffalo were the same regardless of health status. At the level of genus, the changes in some gut bacterial and fungal abundances between both groups were gradually observed. Compared with healthy buffalos, the proportions of 3 bacterial genera (uncultured_bacterium_f_Muribaculaceae, Eubacterium_nodatum_group, and Lachnoclostridium_10) and 1 fungal genus (Pichia) in the mastitis-affected buffalo were significantly increased, whereas 4 bacterial genera (Ruminococcus_2, Candidatus_Stoquefichus, Turicibacter, and Cellulosilyticum) and 4 fungal genera (Cladosporium, Thermothelomyces, Ganoderma and Aspergillus) were significantly decreased. Taken together, this research revealed that there was significant difference in the compositions of the gut microbial community between the healthy and mastitis-affected buffalos. To our knowledge, this is the first insight into the characteristics of the gut microbiota in buffalos with mastitis, which is beneficial to understand the gut microbial information of buffalo in different health states and elucidate the pathogenesis of mastitis from the gut microbial perspective.