Jing Luo

Primary Sjogren's syndrome(pSS) exhibits significant clinical heterogeneity, which poses challenges for accurately assessing disease activity, predicting organ involvement, and diagnosing seronegative patients(SNSS). This study aimed to delineate the metabolic landscape of pSS by integrating metabolomic, lipidomic, and multi-dimensional clinical data to identify novel biomarkers for these purposes and to uncover the intrinsic links between metabolic dysregulation and immune dysfunction. Untargeted metabolomic and lipidomic analyses were performed on plasma samples from a discovery cohort and an independent validation cohort. A machine learning-based metabolic model was developed using selected features, and its diagnostic performance was evaluated by receiver operating characteristic curve (ROC) analysis. Compared with healthy controls(HC), pSS patients exhibited significant alterations in 65 metabolites from the metabolomic analysis and 63 lipids from the lipidomic analysis, indicating systemic metabolic pathway disruptions.Network analysis revealed extensive correlations of metabolomic/lipidomic profiles with clinical parameters and immune cell subsets. A panel of four biomarkers was identified and validated, demonstrating high efficacy in distinguishing SNSS. Furthermore, the levels of redox-related metabolites were significantly associated with age, sex, and anti-SSA antibody status. Seven biomarkers showed significant correlations with the EULAR Sjögren's Syndrome Disease Activity Index(ESSDAI). Specific metabolic signatures were also identified for different organ involvement phenotypes, achieving AUC values of 0.763 and 0.871 for predicting pulmonary and hematological involvement, respectively. This study systematically defines specific metabolic features of pSS, establishes a validated diagnostic model for SNSS, and confirms the close association between metabolic disturbances and clinical heterogeneity. The findings provide novel metabolic biomarkers and insights for the precise diagnosis and management of pSS.

Objective: Bile acids are indispensable modulators in the development of polycystic ovary syndrome (PCOS). Our previous study identified that metformin and canagliflozin have similar efficacy in patients with PCOS combined with insulin resistance (IR). However, the effect of metformin or canagliflozin on bile acid metabolism in patients with PCOS has not been elucidated. The objective of this study was to use targeted metabolomics technology to compare alterations of circulating bile acid metabolites in patients with PCOS before and after treatment with metformin or canagliflozin. Design and Patients: This study was a subanalysis of a previous randomized open‐label study, in which patients with PCOS combined with IR were enrolled and treated with either metformin ( n = 35) or canagliflozin ( n = 33) for 12 weeks. Measurements: The serum bile acid profile was measured using high‐performance liquid chromatography–tandem mass spectrometry (LC–MS/MS). The differences in serum bile acid metabolites in patients with PCOS before and after treatment were analyzed. In addition, the correlation between bile acid metabolites and PCOS‐related clinical characteristics was evaluated. Results: There were no significant differences in serum bile acid metabolites in patients with PCOS before and after canagliflozin treatment. Metformin treatment substantially decreased serum total bile acid levels in patients with PCOS, especially primary conjugated bile acids. The levels of taurochenodeoxycholic acid (TCDCA), glycocholic acid (GCA), and glycochenodeoxycholic acid (GCDCA) showed significant differences from baseline in the serum of patients with PCOS after treatment with metformin. Correlation analysis showed that alterations of GCA, TCDCA, and GCDCA were associated with changes in multiple clinical parameters of patients with PCOS treated with metformin. Conclusion: The effects of metformin and canagliflozin on bile acids metabolism in patients with PCOS are different. The beneficial effects of metformin on PCOS may be related to the changes in bile acid metabolites. Trial Registration: ClinicalTrials.gov : NCT04700839

Background: Regulatory T cells (Tregs) are found to be critical for maintaining immune tolerance to self-antigens; however, their status in primary Sjögren’s syndrome (pSS) remains unclear. We investigated alterations in the abundance of peripheral Tregs in a large pSS cohort and their implications for patients.Methods: Levels of CD4+CD25+FOXP3+Treg cells in the peripheral blood of 624 patients with pSS, and 93 healthy controls (HCs) were detected using modified flow cytometry (FCM). We then performed transcriptome sequencing of CD4+CD25+CD127-Treg cells, and used droplet digital PCR (ddPCR) to validate that the apoptosis-related genes were found in the sorted Treg cells. Apoptosis of CD4+CD25+CD127-Treg cells was verified using 7-AAD and annexin-V staining. We performed FOXP3/activated caspase-3 double immunohistochemistry to characterize features of the labial salivary glands.Results: The peripheral abundance of Treg cells from relapsing pSS patients was significantly contracted, especially in patients with high disease activity. We identified 187 upregulated and 674 downregulated DEGs in sorted Tregs from pSS patients, including five apoptotic pathway hub genes (XIAP, CASP3, CASP10, NFKBIA, and PMAIP1)-a finding consistent with increased Treg apoptosis in pSS. Active caspase-3 was detected in FOXP3+ cells within the minor labial salivary gland tissue of pSS patients. Higher levels of active Caspase-3 were correlated with lower Treg cell numbers. Interestingly, although the downregulation of the PI3K/AKT signaling pathway did not reach statistical significance, this vital pro-survival axis may still contribute to Treg impairment in pSS.Conclusions: These data suggest that the decreased peripheral abundance and increased apoptosis of Treg cells play an important role in the pathogenesis of pSS. Therefore, approaches for increasing Treg numbers in vivo could provide precise pSS therapy.

Background: Regulatory T (Treg) cell depletion-associated immune tolerance deficiency have been shown to play a key role in the pathogenesis of primary Sjögren’s syndrome (pSS). Treg cells mainly express the transcriptional regulator Foxp3 and are characterized by constitutively high expression of inhibitory coreceptor CTLA-4. Herein, the aim of this study was to investigate the potential association of single nucleotide polymorphisms (SNPs) in Foxp3 and CTLA-4 genes with the susceptibility to pSS. Method: Ninety-nine pSS patients and 93 healthy controls were recruited into the retrospective study. Nuclear DNA was extracted from peripheral blood leukocytes, and SNP alleles were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: For the Foxp3 gene, the T allele, the TT and GT genotype in rs3761548G/T, the A allele and AA genotype in rs3761549G/A, as well as the C allele and the TC genotype in rs2280883T/C, were preponderant in pSS. Polymorphisms of rs3761548G/T and rs3761549G/A were found to be associated with anemia or leukopenia, while rs2232365T/C was associated with neutropenia, and rs2280883T/C was demonstrated to have a correlation with anti-SSA(+). For the CTLA-4 gene, the C allele and the CC genotype in rs733618T/C were significantly more prevalent in pSS. rs733618T/C polymorphisms varied significantly in anti-SSA(+), anti-SSB(+) and leukopenia, and rs16840252T/C was associated with ANA(+). Patients with at least six risk alleles had higher Th17 cells and decreased Treg cell counts, accompanied by elevated Th1/Treg, Th2/Treg, and Th17/Treg ratios. And the phenomenon was also observed in patients with four or more variant genotypes. Conclusion: Polymorphisms in Foxp3 and CTLA-4 genes were associated with the susceptibility to pSS. The greater number of mutant sites and variant genotypes an individual possessed, the more susceptible they became to immune dysregulation.

Aberrant number and/or dysfunction of regulatory T cells (Tregs) is associated with the development of rheumatoid arthritis (RA). This study aimed to assess the frequencies of naive Tregs (nTregs) and memory Tregs (mTregs) in the peripheral blood of RA patients and to explore their relationships with cytokine levels. This study involved 97 RA patients categorized into three groups based on Disease Activity Score 28 (DAS28) and 50 healthy controls (HCs). Flow cytometry was employed to quantify Treg subsets in peripheral blood, while serum cytokine concentrations were measured using a flow cytometry bead array. The findings revealed that three RA groups, stratified by disease activity, all exhibited a significant decrease in both the count and percentage of nTregs and an increase in the percentage of mTregs compared to HCs. Notably, the group with high RA disease activity displayed a higher percentage of mTregs than the remission group. Additionally, correlation analysis indicated that IL-2 concentrations were negatively correlated with total T, CD4 + T and Th17 cell counts, and positively correlated with the absolute count of nTregs. This study demonstrated that the count of mTregs in RA patients increased with escalating disease activity, while the count of nTregs remained unchanged. Moreover, IL-2 concentrations were positively correlated with the numbers of Tregs and nTregs, suggesting that IL-2 plays a significant role in modulating Treg subsets. Further studies on targeted therapies aligned with the distribution of mTregs and nTregs in RA patients with varying disease activity could potentially achieve effective remission.