Potential Roles of Oral Microbiota in the Pathogenesis of Immunoglobin A Nephropathy

Oral bacteriome and mycobiome of patients with idiopathic membranous nephropathy with different tongue coatings treated with a Chinese herbal formula

ETHNOPHARMACOLOGICAL RELEVANCE

Moshen Fuyuan Formula (MSFY) is one of the representative Chinese medicine compound for Idiopathic membranous nephropathy (IMN), that originate from Fang Ji Huang Qi decoction in the Han dynasty. IMN is usually accompanied by different tongue coatings in traditional Chinese medicine (TCM), and tongue microorganisms are important factors affecting the formation of the tongue coating. Recently, oral microbiomes, including bacteria and fungi, have been identified as pivotal factors that contribute to disease development. However, the regulation of oral microbiomes by MSFY has not been defined.

AIM OF THE STUDY

In this work, we explore the characteristics of oral bacteria and fungi in IMN patients with different tongue coatings, and clarify the therapeutic effect of MSFY based on oral microbiome.

MATERIALS AND METHODS

We enrolled 24 patients with IMN, including 11 with white tongue (IMN-W) and 13 with yellow tongue (IMN-Y), and recruited an additional 10 healthy individuals. Patients with IMN were treated with the MSFY. The oral bacteriome and fungi before and after treatment were detected using full-length 16S rRNA and internal transcribed spacer gene sequencing.

RESULTS

The therapeutic effect of MSFY on patients with yellow tongue coating was more significant than that on patients with white tongue coating. In terms of oral bacteriome, Campylobacter bacteria were enriched in patients with yellow tongue and could be a promising biomarker for yellow coating. Enrichment of Veillonella parvula_A may partially account for the therapeutic effect of MSFY. As for oral fungi, Malassezia globosa was enhanced in patients with IMN-W and reduced in patients with IMN-Y. Notably, it was reduced by MSFY. We also found that mycobiome-bacteriome interactions were highly complex and dynamic in patients with IMN.

CONCLUSION

The regulation of the dynamic balance between oral fungi and bacteria by MSFY contributes to the treatment of IMN. This study determined the oral bacteriome and mycobiome of patients with IMN with different tongue coatings before and after MSFY treatment, which aids in promoting personalized treatment in clinical TCM and provides direction for investigating the mechanism of Chinese herbal medicines.

Hepatitis B Virus Status and Clinical Outcomes in IgA Nephropathy

Introduction

Immunoglobulin A nephropathy (IgAN) has been reported to coexist with hepatitis B virus (HBV) infection. Despite the clinical significance of this association, there is a lack of comprehensive research investigating the impact of various common conditions following HBV infection and the potential influence of anti-HBV therapy on the progression of IgAN.

Methods

We investigated 3 distinct states of HBV infection, including chronic HBV infection, resolved HBV infection, and the deposition of hepatitis B antigens in renal tissue, in a follow-up database of 1961 patients with IgAN. IgAN progression was defined as a loss of estimated glomerular filtration rate (eGFR) >40%. Multivariable cause-specific hazards models to analyze the relationship between HBV states and IgAN progression.

Results

Chronic HBV infection was identified as an independent risk factor for IgAN progression, supported by both prematching analysis (hazard ratio [HR], 1.61; 95% confidence interval [CI], 1.06-2.44; P = 0.024) and propensity-score matching analysis (HR, 1.74; 95% CI 1.28-2.37; P < 0.001). Conversely, resolved HBV infection showed no significant association with IgAN progression (HR, 1.01; 95% CI 0.67-1.52; P = 0.969). Moreover, the presence of HBV deposition in the kidneys and the utilization of anti-HBV therapy did not appear to be significant risk factors for renal outcomes (P > 0.05).

Conclusion

Chronic HBV infection is an independent risk factor for IgAN progression, whereas resolved HBV infection is not. In patients with IgAN, management of concurrent chronic HBV infection should be enhanced. The presence of HBV deposition in the kidneys and the use of anti-HBV medications do not impact the kidney disease progression in patients with IgAN with concurrent HBV infection.

An Oral Microbial Biomarker for Early Detection of Recurrence of Oral Squamous Cell Carcinoma

Changes in the oral microbiome are associated with oral squamous cell carcinoma (OSCC). Oral microbe-derived signatures have been utilized as markers of OSCC. However, the structure of the oral microbiome during OSCC recurrence and biomarkers for the prediction of OSCC recurrence remains unknown. To identify OSCC recurrence-associated microbial biomarkers for the prediction of OSCC recurrence, we performed 16S rRNA amplicon sequencing on 54 oral swab samples from OSCC patients. Differences in bacterial compositions were observed in patients with vs without recurrence. We found that Granulicatella, Peptostreptococcus, Campylobacter, Porphyromonas, Oribacterium, Actinomyces, Corynebacterium, Capnocytophaga, and Dialister were enriched in OSCC recurrence. Functional analysis of the oral microbiome showed altered functions associated with OSCC recurrence compared with nonrecurrence. A random forest prediction model was constructed with five microbial signatures including Leptotrichia trevisanii, Capnocytophaga sputigena, Capnocytophaga, Cardiobacterium, and Olsenella to discriminate OSCC recurrence from original OSCC (accuracy = 0.963). Moreover, we validated the prediction model in another independent cohort (46 OSCC patients), achieving an accuracy of 0.761. We compared the accuracy of the prediction of OSCC recurrence between the five microbial signatures and two clinicopathological parameters, including resection margin and lymph node counts. The results predicted by the model with five microbial signatures showed a higher accuracy than those based on the clinical outcomes from the two clinicopathological parameters. This study demonstrated the validity of using recurrence-related microbial biomarkers, a noninvasive and effective method for the prediction of OSCC recurrence. Our findings may contribute to the prognosis and treatment of OSCC recurrence.

Systematic Microbiome Dysbiosis Is Associated with IgA Nephropathy

IgA nephropathy (IgAN) is reportedly associated with microbial dysbiosis. However, the microbiome dysregulation of IgAN patients across multiple niches remains unclear. To gain a systematic understanding of microbial dysbiosis, we conducted large-scale 16S rRNA gene sequencing in IgAN patients and healthy volunteers across 1,732 oral, pharynx, gut, and urine samples. We observed a niche-specific increase of several opportunistic pathogens, including Bergeyella and Capnocytophaga in the oral and pharynx, whereas some beneficial commensals decreased in IgAN patients. Similar alterations were also observed in the early versus advanced stage of chronic kidney disease (CKD) progression. Moreover, Bergeyella, Capnocytophaga, and Comamonas in the oral and pharynx were positively associated with creatinine and urea, indicating renal lesions. Random forest classifiers were developed by using the microbial abundance to predict IgAN, achieving an optimal accuracy of 0.879 in the discovery phase and 0.780 in the validation phase. IMPORTANCE This study provides microbial profiles of IgAN across multiple niches and underlines the potential of these biomarkers as promising, noninvasive tools with which to differentiate IgAN patients for clinical applications.

The oral microbiome in autoimmune diseases: friend or foe?

The human body is colonized by abundant and diverse microorganisms, collectively known as the microbiome. The oral cavity has more than 700 species of bacteria and consists of unique microbiome niches on mucosal surfaces, on tooth hard tissue, and in saliva. The homeostatic balance between the oral microbiota and the immune system plays an indispensable role in maintaining the well-being and health status of the human host. Growing evidence has demonstrated that oral microbiota dysbiosis is actively involved in regulating the initiation and progression of an array of autoimmune diseases.Oral microbiota dysbiosis is driven by multiple factors, such as host genetic factors, dietary habits, stress, smoking, administration of antibiotics, tissue injury and infection. The dysregulation in the oral microbiome plays a crucial role in triggering and promoting autoimmune diseases via several mechanisms, including microbial translocation, molecular mimicry, autoantigen overproduction, and amplification of autoimmune responses by cytokines. Good oral hygiene behaviors, low carbohydrate diets, healthy lifestyles, usage of prebiotics, probiotics or synbiotics, oral microbiota transplantation and nanomedicine-based therapeutics are promising avenues for maintaining a balanced oral microbiome and treating oral microbiota-mediated autoimmune diseases. Thus, a comprehensive understanding of the relationship between oral microbiota dysbiosis and autoimmune diseases is critical for providing novel insights into the development of oral microbiota-based therapeutic approaches for combating these refractory diseases.

[Research Progress in the Correlation Between Oral Microbiota and Chronic Kidney Disease]

Chronic kidney disease (CKD), one of the common clinical urological diseases, is increasingly more prevalent in recent years and has emerged as a major concern of public health around the globe. The continuous recurrence of CKD caused by renal function impairment leads eventually to irreversible renal failure and severe systemic complications, which causes severe negative impact on the quality of life of the patient. As an essential component of human microbiome, oral microbiota plays a major role in maintaining health, and there has been research suggesting close association between oral dysbiosis and CKD. It is therefore of great clinical significance to understand the correlation between CKD and oral microbiota. Herein, we reviewed the characteristics of oral microbiota of CKD patients, the possible mechanisms of oral microbiota's involvement in the pathogenesis and development of CKD, and the latest research findings on oral dysbiosis and CKD, with a view to finding new approaches to early prevention and control of CKD through oral microbial targets.

Findings on the Relationship Between Intestinal Microbiome and Vasculitis

The microbiome has been implicated in small-, medium-, large-, and variable-vessel vasculitis. Dysbiosis can frequently be found in vasculitis patients with altered microbial diversity and abundance, compared with those with other diseases and healthy controls. Dominant bacteria discovered in different studies vary greatly, but in general, the intestinal microbiome in vasculitis patients tends to contain more pathogenic and less beneficial bacteria. Improvement or resolution of dysbiosis has been observed after treatment in a few longitudinal studies. In addition, some molecular changes in intestinal permeability and immune response have been found in animal models of vasculitis diseases.

Gut Microbes in Immunoglobulin A Nephropathy and Their Potential Therapeutic Applications

Microbial ecosystem consists of a complex community of bacterial interactions and its host microenvironment (tissue, cell, metabolite). Because the interaction between gut microbiota and host involves many diseases and seriously affects human health, the study of the interaction mechanism between gut microbiota and host has attracted great attention. The gut microbiome is made up of 100 trillion bacteria that have both beneficial and adverse effects on human health. The development of IgA Nephropathy results in changes in the intestinal microbial ecosystem that affect host physiology and health. Similarly, changes in intestinal microbiota also affect the development of IgA Nephropathy. Thus, the gut microbiome represents a novel therapeutic target for improving the outcome of IgA Nephropathy, including hematuria symptoms and disease progression. In this review, we summarize the effect of intestinal microbiota on IgA Nephropathy in recent years and it has been clarified that the intestinal microbiota has a great influence on the pathogenesis and treatment of IgA Nephropathy.