Association between primary Sjögren's syndrome and gut microbiota disruption: a systematic review and meta-analysis.

Evidence of gut microbiota disruption for numerous autoimmune diseases has accumulated. Recently, the relationship between the microbiota and primary Sjögren's disease has been increasingly investigated but has yet to be systematically elucidated. Therefore, a meta-analysis of publications dealing on topic was conducted. Case-control studies comparing primary Sjögren's syndrome patients and healthy controls (HCs) were systematically searched in nine databases from inception to March 1, 2023. The primary result quantitatively evaluated in this meta-analysis was the α-diversity. The secondary results qualitatively extracted and analyzed were the ß-diversity and relative abundance. In total, 22 case-control studies covering 915 pSS patients and 2103 HCs were examined. The quantitative analysis revealed a slight reduction in α-diversity in pSS patients compared to HCs, with a lower Shannon-Wiener index (SMD = - 0.46, (- 0.68, - 0.25), p < 0.0001, I2 = 71%), Chao1 richness estimator (SMD = - 0.59, (- 0.86, - 0.32), p < 0.0001, I2 = 81%), and ACE index (SMD = - 0.92, (- 1.64, - 0.19), p = 0.01, I2 = 86%). However, the Simpson index (SMD = 0.01, (- 0.43, 0.46) p = 0.95, I2 = 86%) was similar in the two groups. The ß-diversity significantly differed between pSS patients and HCs. Variations in the abundance of specific microbes and their metabolites and potential functions contribute to the pSS pathogenesis. Notably, the abundance of the phylum Firmicutes decreased, while that of Proteobacteria increased. SCFA-producing microbes including Ruminococcaceae, Lachnospiraceae, Faecalibacterium, Butyricicoccus, and Eubacterium hallii were depleted. In addition to diversity, the abundances of some specific microbes were related to clinical parameters. According to this systematic review and meta-analysis, gut microbiota dysbiosis, including reduced diversity, was associated with proinflammatory bacterium enrichment and anti-inflammatory bacterium depletion in pSS patients. Further research on the relationship between the gut microbiota and pSS is warranted.

Identification of Key Genes for Pyroptosis-Induced Salivary Gland Inflammation in Sjogren's Syndrome Based on Microarray Data and Immunohistochemistry Analysis.

Purpose: Sjogren's Syndrome (SS) is a systemic autoimmune disease primarily characterized by dysfunction of the exocrine glands. Research into the etiology and pathogenesis of salivary glands (SG) inflammation of SS is very limited. The aim of this study was to identify potential pyroptosis-related genes in SG inflammation through bioinformatics analysis and validation of the SG in SS. Methods: GSE157159 dataset and GSE159574 dataset were downloaded from Gene Expression Omnibus (GEO). Differentially Expressed Genes (DEGs) analysis was used to screen DEGs from SS and non-SS SG samples. Pyroptosis-related genes were obtained from GeneCards. After intersecting DEGs with pyroptosis-related genes, the pyroptosis-related DEGs in SS were obtained. Subsequently, ClueGO enrichment analysis, Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis, Protein-protein Interaction (PPI), and identification and co-expression analysis of hub genes were performed. Subsequently, we collected SG samples from 17 SS patients and 17 non-SS patients and validated the expression of two hub genes (GZMA, GBP1) and characteristic genes (GSDMD) of pyroptosis through immunohistochemistry. The accuracy of hub genes as biomarkers for predicting SS was evaluated by receiver operating characteristic (ROC) curve. Results: 834 DEGs were selected from the GSE157159 dataset, and a total of 39 pyroptosis-related DEGs were obtained. Functional analysis showed that these DEGs were significantly enriched in some inflammatory signaling pathways. Through the intersection of seven algorithms proposed by CytoHubba and validation using the GSE159574 dataset, 11 hub genes were identified, including IL18, AIM2, CCL5, CD274, GBP1, GBP5, GZMA, GZMB, TLR8, TNFS13B, and ICAM1. Finally, the results of immunohistochemistry showed that GSDMD, GZMA and GBP1 were all significantly highly expressed in SG from SS. And ROC analysis showed a high combined diagnostic value of the 3 genes (AUC=0.8858). Conclusion: Our study revealed enhanced levels of pyroptosis in the SS. GZMA and GBP1 were identified as candidate genes for pyroptosis-induced inflammation of the SG in SS, which may be used as biomarkers or potential therapeutic targets for SS.

Network pharmacology identifies the inhibitory effect of Yiqiyangyinquyu prescription on salivary gland inflammation in Sjögren's syndrome.

This study aimed to explore the mode of action of Yiqiyangyinquyu prescription (YP) against Sjögren's syndrome (SS) by combining network pharmacology with molecular docking techniques. YP's active components and target proteins were identified using the BATMAN-traditional Chinese medicine database. Concurrently, targets associated with SS were extracted from databases, including Genecards, Online Mendelian Inheritance in Man, and Therapeutic Target Database. The standard targets were then imported into the STRING database to construct a protein-protein interaction network. We then conducted gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses, which were succeeded by molecular docking studies to validate core active components and key targets. Finally, in vitro experiments and molecular dynamics simulation were conducted to substantiate the therapeutic efficacy of YP in treating SS. A total of 206 intersection targets and 46 active compounds were identified. Gene ontology analysis unveiled that YP targets were primarily enriched in cellular responses to chemical stress, inflammation, and cell proliferation. Key enriched signaling pathways encompassed the interleukin 17, hypoxia-inducible factor-1, tumor necrosis factor (TNF-α), and advanced glycation end products-receptor for AGEs (AGE-RAGE) signaling pathways. Molecular docking results demonstrated high-affinity between neotanshinone C, tanshiquinone B, miltionone I, TNF-α, interleukin 1 beta (IL-1ß), and interleukin 6 (IL-6). Noteworthy, TNF-α, considered the most important gene in YP against SS, binds to YP most stably, which was further validated by molecular dynamics simulation. In vitro experiments confirmed YP's capacity to reduce TNF-α, IL-1ß, and IL-6 expression, effectively alleviating SS-related inflammation. YP demonstrated a significant anti-inflammatory effect by suppressing inflammatory cytokines (TNF-α, IL-6, and IL-1ß), providing experimental evidence for its clinical application in treating SS.

Serum Metabolomics Analysis of Skin-Involved Systemic Lupus Erythematosus: Association of Anti-SSA Antibodies with Photosensitivity.

Purpose: Systemic lupus erythematosus is a heterogeneous autoimmune disease in which skin involvement is a common manifestation. It is currently thought that the photosensitivity of SLE skin involvement is associated with anti-SSA antibodies. This study aimed to expand the current state of knowledge surrounding the molecular pathophysiology of SLE skin photosensitivity through Serum metabolomics analysis. Patients and Methods: The serum metabolites of 23 cases of skin-involved SLE (SI) group, 14 cases of no SI (NSI) group, and 30 cases of healthy controls (HC) were analyzed by using UPLC-MS/MS technology, and subgroup analysis was performed according to the expression of anti-SSA antibodies in SI. MetaboAnalyst 5.0 was used for enrichment analysis and ROC curve construction, identifying serum metabolic markers of skin-involved SLE associated with anti-SSA antibodies. Results: We identified several metabolites and metabolic pathways associated with SLE photosensitivity. Two metabolites, SM (d18:1/24:0) and gamma-CEHC can distinguish between anti-SSA antibody-positive and negative SI, with AUC of 0.829 and 0.806. These two photosensitization-related substances may be potential markers of skin involvement in SLE associated with anti-SSA antibody. Conclusion: This study provides new insights into the pathogenesis of SI patients, and provides a new molecular biological basis for the association between anti-SSA antibodies and skin photoallergic manifestations of SLE.

Identification of key genes in salivary gland in Sjögren's syndrome complicated with Hashimoto thyroiditis: Common pathogenesis and potential diagnostic markers.

The coexistence of Sjögren's syndrome (SS) and Hashimoto thyroiditis (HT) has been confirmed, but the common mechanism of its co-occurrence remains unknown. This study aims to further explore the underlying mechanism and biomarkers for the co-occurrence of SS and HT. The Gene Expression Omnibus databases were used to obtain gene expression profiles for SS (GSE127952 and GSE23117) and HT (GSE29315 and GSE138198). Following identifying SS and HT's shared differentially expressed genes, functional annotation, protein-protein interaction network creation, and module assembly were performed to discover hub genes. H&E staining and immunohistochemistry were performed to validate the expression of the hub genes in salivary glands. Finally, the receiver operating characteristic (ROC) curve was utilized to assess the discrimination of the hub genes as biomarkers in predicting SS, this study applied CIBERSORTx to analyze the immune infiltration in SS and HT in addition. A total of 48 common differentially expressed genes (48 upregulated genes and 0 downregulated genes) were chosen for further investigation. We analyzed the expression and function of PTPRC, CD69, IKZF1, and lymphocyte cytosolic protein 2 via H&E, immunohistochemistry, and ROC analysis. The 4 hub genes were mainly enriched in the T-cell receptor signaling pathway. We then evaluated and verified the diagnosis value of 4 hub genes in clinical minor labial gland biopsy of SS with HT, SS without HT, and non-SS. ROC analysis revealed that the 4 hub genes had a strong diagnostic value. Our study showed the common pathogenesis of SS and HT. These hub genes and diagnostic models may put forward some new insights for diagnosing and treating SS complicated with HT.

Genome-wide DNA methylation sequencing reveals epigenetic features and potential biomarkers of Sjögren syndrome.

AIM: Sjögren syndrome (SS) is a slowly progressive, inflammatory, autoimmune disease. The aim of this study was to construct the DNA methylation profiles of whole blood of SS patients and healthy controls (HC), and to explore the role of differentially methylated genes in the pathogenesis of the disease. METHODS: Whole-genome bisulfite sequencing was performed on three SS patients and four HC. The biological function of genes associated with differentially methylated regions (DMRs) was investigated using Gene Ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis, using network-based key driver analysis (KDA) to find KDA genes. In clinical samples of SS patients and controls, the expression levels of KDA genes were validated by quantitative real-time polymerase chain reaction and immunohistochemical analysis. Moreover, the diagnostic value of KDA genes for SS was confirmed using receiver operating characteristic curves. RESULTS: We identified 322 DMRs, annotated as 162 associated genes. Six genes were selected via the number of networks of KDA genes. Differential expression of genes such as human leukocyte antigen (HLA) class I, ADAR, and OAS2 was observed in patients' peripheral blood mononuclear cells and the minor salivary glands, which can be used as potential diagnostic biomarkers for SS. CONCLUSION: Clinical sample validation suggested that HLA class I, ADAR, and OAS2 might play a role in the development of SS. Our study shows epigenetic regulatory mechanisms and potential disease markers associated with SS, which in turn will enable us to identify new therapeutic targets.

Whole-genome bisulfite sequencing identified the key role of the Src family tyrosine kinases and related genes in systemic lupus erythematosus.

BACKGROUND: As a multisystemic autoimmune illness, the basic mechanisms behind the pathophysiology of systemic lupus erythematosus (SLE) remain poorly understood. OBJECTIVE: We aimed to investigate the possible significance of SLE's DNA methylation and gain further insight into potential SLE-related biomarkers and therapeutic targets. METHODS: We used whole genome bisulfite sequencing (WGBS) method to analyze DNA methylation in 4 SLE patients and 4 healthy people. RESULTS: 702 differentially methylated regions (DMRs) were identified, and 480 DMR-associated genes were annotated. We found the majority of the DMR-associated elements were enriched in repeat and gene bodies. The top 10 hub genes identified were LCK, FYB, PTK2B, LYN, CTNNB1, MAPK1, GNAQ, PRKCA, ABL1, and CD247. Compared to the control group, LCK and PTK2B had considerably decreased levels of mRNA expression in the SLE group. Receiver operating characteristic (ROC) curve suggested that LCK and PTK2B may be potential candidate biomarkers to predict SLE. CONCLUSIONS: Our study improved comprehension of the DNA methylation patterns of SLE and identified potential biomarkers and therapeutic targets for SLE.

Lipidomics Changes in a Murine Model of Neuropsychiatric Lupus.

Purpose: Neuropsychiatric lupus (NPSLE) is one of the important manifestations of systemic lupus erythematosus. Previous studies mainly focused on the disruption of the blood-brain barrier and the production of brain-reactive autoantibodies, However, there is no comprehensive lipidomic analysis in NPSLE. Therefore, this research evaluated the lipidomic analysis in the hippocampus and liver of NPSLE mice with mood disorders, to explore the influence of the liver-brain axis on this disease. Methods: MRL/lpr mice and MRL/mpj mice were respectively used as NPSLE and control groups. Behavioral tests and systemic disease characteristics of mice were assessed at the age of 18 weeks. Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS) was used for lipid metabolite determination. Multivariate statistical analysis was used to identify lipid metabolites that were differentially expressed in two groups. Results: Our results showed that 355 and 405 lipid metabolites were differentially expressed between the NPSLE and control groups in the hippocampus and liver. According to the pathway enrichment analysis, several pathways were affected, and the glycerophospholipid metabolism pathway was most relevant to the mouse's depressive behavior. Conclusion: Based on UPLC-MS/MS, the results provide evidence for how the liver-brain axis affects NPSLE and improve the understanding of NPSLE pathogenesis.

Tumor-derived extracellular vesicles in melanoma immune response and immunotherapy.

Tumor-derived extracellular vesicles (EVs) are key immune regulators of the tumor microenvironment. They reshape the immune microenvironment and prevent antitumor immune responses via their immunosuppressive cargo, thereby determining cancer responsiveness to treatment. In the immune microenvironment of melanoma, tumor-derived EVs influence tumor progression by regulating innate and adaptive immune responses. Tumor-derived EV-based therapy is a cutting-edge and promising strategy for inhibiting melanoma progression and enhancing antitumor immunity. This review aimed to summarize the regulatory roles of EVs in the immune responses and immunotherapy of patients with melanoma. This paper provided insights into future exploration directions and potential clinical strategies targeting EVs for melanoma treatment.

Bioinformatics Analysis for Identification of Key Genes in Salivary Gland and the Potential of a Combination of Biomarkers for the Diagnosis of SS.

PURPOSE: Sjögren's syndrome (SS) is a systemic autoimmune disease mainly characterized by dysfunction of exocrine glands. Studies on diagnosis models specific for SS patients are very limited. We aimed to use gene expression datasets from salivary glands to identify aberrant differentially expressed genes (DEGs) and pathways by bioinformatics and validate candidate genes by clinical minor labial gland biopsy (MSGB) samples, and finally build a combined gene quantitative diagnosis model of SS. PATIENTS AND METHODS: Original datasets GSE23117, GSE7451, and GSE127952 were obtained from the Gene Expression Omnibus database (GEO) and integrated and analyzed for differentially expressed genes in SS salivary glands. ClueGO and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of upregulated and downregulated DEGs were performed, and protein-protein interaction (PPI) networks were constructed using the STRING and Cytoscape database. H&E staining and immunohistochemistry were used to validate the expression levels of four hub genes in salivary glands. Finally, a receiver operating characteristic (ROC) curve of the combined diagnosis of four hub genes was analyzed in SS patients and non-SS patients in order to explore the diagnostic efficacy of these genes compared with conventional FS in SS. RESULTS: Fifty-three upregulated genes and fifteen downregulated genes were identified. We analyzed the expression and function of four hub genes via H&E, immunohistochemistry, and ROC analysis. We then evaluated and verified the diagnosis value of four hub genes, STAT1, MNDA, IL10RA, and CCR1 in MSGB of SS and non-SS. A combined diagnosis model of four indicators was established to identify patients' discrete data on the foci size (AUC=0.915). CONCLUSION: The expression of STAT1, MNDA, and IL10RA may be potential biological indicators for SS diagnosis. Compared with FS, a combined diagnosis model of quantitative gene expression could potentially contribute to improving the sensitivity and specificity of MSGB of SS.

Anti-alanyl tRNA positive antisynthase syndrome with Kaposi sarcoma.

We report a rare case of antisynthase syndrome (ASS) complicated with Kaposi sarcoma, analyze its clinical characteristics, and review the literature on the topic. An 80-year-old male patient developed fever, cough, and shortness of breath. Lung high-resolution computed tomography showed nonspecific interstitial pneumonia in both lungs, and myositis antibody examination showed strongly positive anti-alanyl tRNA synthase (PL-12) antibodies. Based on these findings, the patient was diagnosed with ASS. After full-dose glucocorticoid treatment, the symptoms of fever and cough were relieved, but skin thickening and pigmentation in both feet were observed. We confirmed Kaposi sarcoma through skin pathology and immunohistochemical examination of the bottom of the patient's feet, and the patient was transferred to a cancer hospital for radiotherapy. ASS presents with some skin changes that might lead to misdiagnosis. ASS complicated with Kaposi sarcoma is rare, and to our knowledge, this is the first case reported in China.