Intestinal dysbiosis featuring abundance of Streptococcus associates with Henoch-Schönlein purpura nephritis (IgA vasculitis with nephritis) in adult

Gut dysbiosis was inevitable, but tolerance was not: temporal responses of the murine microbiota that maintain its capacity for butyrate production correlate with sustained antinociception to chronic voluntary morphine

The therapeutic benefits of opioids are compromised by the development of analgesic tolerance, which necessitates higher dosing for pain management thereby increasing the liability for dependence and addiction. Rodent models indicate opposing roles of the gut microbiota in tolerance: morphine-induced gut dysbiosis exacerbates tolerance, whereas probiotics ameliorate tolerance. Not all individuals develop tolerance which could be influenced by differences in microbiota, and yet no study has capitalized upon this natural variation to identify specific features linked to tolerance. We leveraged this natural variation in a murine model of voluntary oral morphine self-administration to elucidate the mechanisms by which microbiota influences tolerance. Although all mice shared similar and predictive morphine-driven microbiota changes that largely masked informative associations with variability in tolerance, our high-resolution temporal analyses revealed a divergence in the progression of dysbiosis that best explained differences in the development in tolerance. Mice that did not develop tolerance also maintained a higher abundance of taxa capable of producing the short-chain fatty acid (SCFA) butyrate, known to bolster intestinal barriers, suppress inflammation, and promote neuronal homeostasis. Furthermore, dietary butyrate supplementation significantly reduced the development of tolerance. These findings could inform immediate therapies to extend the analgesic efficacy of opioids.

Regulation of the innate immune response and gut microbiome by p53

p53 is a key tumor suppressor mutated in half of human cancers. In recent years, p53 was shown to regulate a wide variety of functions. From the transcriptome analysis of 24 tissues of irradiated mice, we identified 553 genes markedly induced by p53. Gene Ontology (GO) enrichment analysis found that the most associated biological process was innate immunity. 16S rRNA-seq analysis revealed that Akkermansia, which has anti-inflammatory properties and is involved in the regulation of intestinal barrier integrity, was decreased in p53-knockout (p53-/- ) mice after radiation. p53-/- mice were susceptible to radiation-induced GI toxicity and had a significantly shorter survival time than p53-wild-type (p53+/+ ) mice following radiation. However, administration of antibiotics resulted in a significant improvement in survival and protection against GI toxicity. Mbl2 and Lcn2, which have antimicrobial activity, were identified to be directly transactivated by p53 and secreted by liver into the circulatory system. We also found the expression of MBL2 and LCN2 was decreased in liver cancer tissues with p53 mutations compared with those without p53 mutations. These results indicate that p53 is involved in shaping the gut microbiome through its downstream targets related to the innate immune system, thus protecting the intestinal barrier.

Investigation of Gut Microbiota Disorders in Sepsis and Sepsis Complicated with Acute Gastrointestinal Injury Based on 16S rRNA Genes Illumina Sequencing

Background

Sepsis is a life-threatening organ dysfunction caused by the host's dysfunctional response to infection, which can cause acute gastrointestinal injury (AGI). The gut microbiota is dynamic and plays a role in the immune and metabolic. The aim of this study was to investigate the composition and function of gut microbiota in patients with sepsis, as well as the gut microbiome that may be involved in the occurrence of AGI.

Methods

A total of 23 stool samples from healthy control individuals and 41 stool samples from sepsis patients were collected. Patients with sepsis were followed up for one week to observe whether AGI has occurred. Finally, 41 patients included 21 sepsis complicated with AGI (referred to as Com-AGI) and 20 sepsis without complicated with AGI (referred to as No-AGI). The gut microbiota was analyzed by 16S rRNA gene sequencing, followed by composition analysis, difference analysis, correlation analysis, functional prediction analysis.

Results

The diversity and evenness of gut microbiota were decreased in patients with sepsis. Compared with No-AGI, the gut microbiota of Com-AGI has higher community diversity, richness, and phylogenetic diversity. Escherichia-Shigella, Blautia and Enterococcus may be important indicators of sepsis. The correlation analysis showed that aspartate aminotransferase (AST) and Barnesiella have the most significant positive correlation. Moreover, Clostridium_innocuum_group, Christensenellaceae_R-7_group and Eubacterium were all significantly correlated with LAC and DAO. Clostridium_innocuum_group, Barnesiella, Christensenellaceae_R-7_group and Eubacterium may play important roles in the occurrence of AGI in sepsis. PICRUSt analysis revealed multiple functional pathways involved in the relationship between gut microbiota and sepsis, including starch degradation V, glycogen degradation I (bacterial), Lipoic acid metabolism and Valine, leucine and isoleucine biosynthesis. BugBase analysis showed that the gut microbiota with Aerobic phenotype may play an important role in sepsis.

Conclusion

Dysfunction of gut microbiota was associated with sepsis and AGI in patients with sepsis.

Alterations of the gut microbiota in the lupus nephritis: a systematic review

BACKGROUND

Emerging evidence suggests that gut microbiota dysbiosis may play a critical role in the development of lupus nephritis (LN). However, the specific characteristics of the gut microbiota in individuals with LN have not been fully clarified.

METHODS

The PubMed, Web of Science, and Embase databases were systematically searched for clinical and animal studies related to the relationship between LN and gut microbiota from inception until October 1, 2023. A semiquantitative analysis was used to assess the changes in gut microbial profiles.

RESULTS

A total of 15 clinical studies were selected for analysis, which included 138 LN patients, 441 systemic lupus erythematosus patients, and 1526 healthy controls (HCs). Five different types of LN mouse models were included in 5 animal studies. The alpha diversity was decreased in LN patients compared to HCs. A significant decrease in the Firmicutes/Bacteroidetes (F/B) ratio is considered a hallmark of pathological conditions. Specifically, alterations in the abundance of the phylum Proteobacteria, genera Streptococcus and Lactobacillus, and species Ruminococcus gnavus and Lactobacillus reuteri may play a critical role in the pathogenesis of LN. Remarkably, the gut taxonomic chain Bacteroidetes-Bacteroides-Bacteroides thetaiotaomicron was enriched in LN patients, which could be a crucial characteristic of LN patients. The increased level of interleukin-6, imbalance of regulatory T cells and T helper 17 cells, and decreased level of the intestinal tight junction proteins zonula occludens-1 and claudin-1 also might be related to the pathogenesis of LN.

CONCLUSIONS

Specific changes in the abundance of gut microbiota such as decreased F/B ratio, and the level of inflammatory indicators, and markers of intestinal barrier dysfunction may play a crucial role in the pathogenesis of LN. These factors could be effective diagnostic and potential therapeutic targets for LN.

Landscape of intestinal microbiota in patients with IgA nephropathy, IgA vasculitis and Kawasaki disease

Objective

To explore the common differential flora of IgAN, Kawasaki disease and IgA vasculitis by screening and analyzing the differential intestinal flora between the three disease groups of IgAN, Kawasaki disease and IgA vasculitis and their healthy controls.

Methods

Papers on 16srRNA sequencing-related intestinal flora of IgAN, Kawasaki disease and IgA vasculitis were searched in databases, the literature was systematically collated and analysed, the original data was download from the relevant databases, and then the operational taxonomic unit and species classification analysis were performed. Besides, Alpha diversity analysis and Beta diversity analysis were performed to screen for IgAN, Kawasaki disease and I1gA vasculitis groups and finally compare the common intestinal differential flora among the three groups.

Results

Among the common differential flora screened, Lachnospiracea_incertae_sedis was lower in both the IgAN and Kawasaki disease groups than in the respective healthy controls; Coprococcus was low in the IgAN group but high in the IgA vasculitis group. Fusicatenibacter was lower in both the Kawasaki disease and IgA vasculitis groups than in their respective healthy controls, and Intestinibacter was low in the Kawasaki disease group, but its expression was high in the IgA vasculitis group.

Conclusion

The dysbiosis of the intestinal flora in the three groups of patients with IgAN, Kawasaki disease and IgA vasculitis, its effect on the immunity of the organism and its role in the development of each disease group remain unclear, and the presence of their common differential flora may further provide new ideas for the association of the pathogenesis of the three diseases.

Specific alterations of gut microbiota in patients with membranous nephropathy: A systematic review and meta-analysis

Background: The pathogenesis of idiopathic membranous nephropathy (IMN) has not yet been thoroughly clarified, and gut dysbiosis may be a contributor to IMN. However, the characterization of gut microbiota in patients with IMN remains uncertain. Methods: Cochrane Library, PubMed, China National Knowledge Internet, Web of Science, and Embase were used to search for studies through 18 May 2022. A meta-analysis based on the standardized mean difference (SMD) with 95% confidence interval (CI) was conducted on the alpha diversity index. The between-group comparison of the relative abundance of gut microbiota taxa and the beta diversity were extracted and qualitatively analyzed. Results: Five studies were included involving 290 patients with IMN, 100 healthy controls (HCs), and 129 patients with diabetic kidney disease (DKD). The quantitative combination of alpha diversity indices indicated that although bacterial richness was impaired [ACE, SMD = 0.12, (-0.28, 0.52), p = 0.55, I 2 = 0%; Chao1, SMD = -0.34, (-0.62, -0.06), p < 0.05, I 2 = 36%], overall diversity was preserved [Shannon, SMD = -0.16, (-0.64, 0.31), p = 0.50, I 2 = 53%; Simpson, SMD = 0.27, (-0.08, 0.61), p = 0.13, I 2 = 0%]. The beta diversity was significantly varied compared to HCs or DKD patients. Compared to HCs, the abundance of Proteobacteria increased, while that of Firmicutes decreased at the phylum level. Furthermore, the abundance of Lachnospira were depleted, while those of Streptococcus were enriched at the genus level. Proteobacteria and Streptococcus were also increased compared to DKD patients. Conclusions: The expansion of Proteobacteria and depletion of Lachnospira may be critical features of the altered gut microbiota in patients with IMN. This condition may play an important role in the pathogenesis of IMN and could provide bacterial targets for diagnosis and therapy.

Development and validation of a nomogram to predict recurrence in children with Henoch-Schönlein purpura

BACKGROUND

To screen risk factors for the recurrence in children with Henoch-Schönlein Purpura (HSP) and to develop and validate a nomogram for recurrence in children with HSP.

METHODS

During September 2019 and September 2021, 212 children with HSP were selected in this study. The children were divided into two sets in a proportion of 7:3 using R language, with the first group as the training sets and the second as the internal validation sets. The related variables were analyzed by univariate and multivariate logistic regression analyses, and a nomogram for predicting the recurrence in HSP children was established. The nomogram was evaluated by ROC curve, calibration curve and decision curve, and 1000 times bootstrap resampling method was used to verify the model internally.

RESULTS

Univariate and multivariate regression analyses identified respiratory infection, without preventive medication and diet restriction, age, allergen positive and abnormal urine routine as risk factors for the recurrence in children with HSP. Those risk factors were used to construct a predictive nomogram. The calibration curves revealed excellent accuracy of the predictive nomogram model, internally and externally.

CONCLUSIONS

We constructed and validated a clinical nomogram to predict the recurrence in children with HSP. We confirmed that respiratory tract infection, without preventive medication and diet restriction, age, allergen positive and abnormal urine routine were independent recurrence risk factors. This nomogram had a good performance in clinical decision-making.