Rheumatoid arthritis (RA) is a progressive autoimmune disease. Due to local infiltration and damage to the joints, activated CD4⁺ T cells play a crucial role in the progression of RA. However, the exact regulatory mechanisms are perplexing, which makes the effective management of RA frustrating. This study aimed to investigate the effect of mitochondria fission on the polarization and migration of CD4⁺ T cells as well as the regulatory mechanism of NAR, so as to provide enlightenment on therapeutic targets and novel strategies for the treatment of RA. In this study, a collagen-induced arthritis (CIA) model was established, and rats were randomly given saline or naringenin (NAR, 10 mg/kg, 20 mg/kg, 50 mg/kg, i.p.) once a day, before being euthanized on the 42nd day of primary immunization. The pain-like behavior, articular index scores, account of synovial-infiltrated CD4⁺ T cells, and inflammatory factors were investigated in each group. In vitro, spleen CD4⁺ T lymphocytes were derived from each group. In addition, mitochondrial division inhibitor 1 (Mdivi-1) or NAR was added to the cell medium containing C-X-C motif chemokine ligand 12 (CXCL12) in order to induce CD4⁺ T lymphocytes, respectively. The polarization capacity of CD4⁺ T cells was evaluated through the immunofluorescence intensity of the F-actin and myosin light chain phosphorylated at Ser19 (pMLC S19), and the mitochondrial distribution was determined by co-localization analysis of the translocase of outer mitochondrial membrane 20 (TOM20, the mitochondrial marker) and intercellular adhesion molecule 1 (ICAM1, the uropod marker). The mitochondrial fission was investigated by detecting dynamin-related protein 1 (Drp1) and mitochondrial fission protein 1 (Fis1) using Western blot and immunofluorescence. This study revealed that high-dose NAR (50 mg/kg, i.p.) alleviated pain-like behavior and articular index scores, reduced the serum level of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α), and accounted for CD4⁺ T lymphocytes that infiltrated into the synovial membrane of the CIA group. Meanwhile, NAR (50 mg/kg, i.p.) suppressed the polarization of spleen CD4⁺ T lymphocytes, reduced the redistribution of mitochondria in the uropod, and inhibited the expression of Drp1 and Fis1 in the CIA model. Furthermore, the in vitro experiments confirmed that NAR reduced mitochondrial fission, which in turn inhibited the CXCL12-induced polarization and migration of CD4⁺ T lymphocytes. Our results demonstrated that the flavonoid NAR was a promising drug for the treatment of RA, which could effectively interfere with mitochondrial fission, thus inhibiting the polarization and migration of CD4⁺ T cells in the synovial membrane.

Background: Endometriosis (EMs) is an enigmatic disease of yet-unknown pathogenesis. Disulfidptosis, a novel identified form of programmed cell death resulting from disulfide stress, stands a chance of treating diverse ailments. However, the potential roles of disulfidptosis-related genes (DRGs) in EMs remain elusive. This study aims to thoroughly explore the key disulfidptosis genes involved in EMs, and probe novel diagnostic markers and candidate therapeutic compounds from the aspect of disulfidptosis based on bioinformatics analysis, machine learning, and animal experiments.Results: Enrichment analysis on key module genes and differentially expressed genes (DEGs) of eutopic and ectopic endometrial tissues in EMs suggested that EMs was closely related to disulfidptosis. And then, we obtained 20 and 16 disulfidptosis-related DEGs in eutopic and ectopic endometrial tissue, respectively. The protein-protein interaction (PPI) network revealed complex interactions between genes, and screened nine and ten hub genes in eutopic and ectopic endometrial tissue, respectively. Furthermore, immune infiltration analysis uncovered distinct differences in the immunocyte, human leukocyte antigen (HLA) gene set, and immune checkpoints in the eutopic and ectopic endometrial tissues when compared with health control. Besides, the hub genes mentioned above showed a close correlation with the immune microenvironment of EMs. Furthermore, four machine learning algorithms were applied to screen signature genes in eutopic and ectopic endometrial tissue, including the binary logistic regression (BLR), the least absolute shrinkage and selection operator (LASSO), the support vector machine-recursive feature elimination (SVM-RFE), and the extreme gradient boosting (XGBoost). Model training and hyperparameter tuning were implemented on 80% of the data using a ten-fold cross-validation method, and tested in the testing sets which determined the excellent diagnostic performance of these models by six indicators (Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value, Accuracy, and Area Under Curve). And seven eutopic signature genes (ACTB, GYS1, IQGAP1, MYH10, NUBPL, SLC7A11, TLN1) and five ectopic signature genes (CAPZB, CD2AP, MYH10, OXSM, PDLIM1) were finally identified based on machine learning. The independent validation dataset also showed high accuracy of the signature genes (IQGAP1, SLC7A11, CD2AP, MYH10, PDLIM1) in predicting EMs. Moreover, we screened 12 specific compounds for EMs based on ectopic signature genes and the pharmacological impact of tretinoin on signature genes was further verified in the ectopic lesion in the EMs murine model.Conclusion: This study verified a close association between disulfidptosis and EMs based on bioinformatics analysis, machine learning, and animal experiments. Further investigation on the biological mechanism of disulfidptosis in EMs is anticipated to yield novel advancements for searching for potential diagnostic biomarkers and revolutionary therapeutic approaches in EMs.

Chronic pain, a hallmark symptom of rheumatoid arthritis (RA), is strongly linked to central sensitization driven by spinal glial cell activation. Despite its clinical significance, the precise mechanisms remain unclear. Recent findings highlight the crucial role of interactions between circulating monocytes and central nervous system glial cells in chronic pain associated with autoimmune conditions. Our study focuses on CD4⁺ T-cell infiltration into the spinal dorsal horn (SDH) after collagen-induced arthritis (CIA) immunization. Immunohistochemistry results indicate that CD4⁺ T cells are critical in initiating arthritic pain. Intrathecal injection of CD4⁺ T cells in naïve mice induced glial activation and pain-like behaviors, while neutralizing antibodies suppressed these effects. Elevated phosphorylation of collapsin response mediator protein 2 (CRMP2) in CIA-derived CD4⁺ T lymphocytes was closely associated with pathological spinal infiltration. To modulate CRMP2 phosphorylation, we used naringenin (NAR), a known CRMP2 regulator, and (S)-Lacosamide ((S)-LCM), a specific inhibitor of phosphorylated CRMP2. Both compounds reduced CD4⁺ T-cell infiltration into the SDH and attenuated central sensitization in CIA rats. CRMP2 conditional knockout (cKO) in CD4⁺ T cells significantly alleviated arthritic pain. In addition, in vitro blood brain barrier models and Transwell assays showed impaired CD4⁺ T-cell migration and transendothelial invasion upon cKO or treatment with NAR and (S)-LCM. These interventions also decreased the proportion of polarized CD4⁺ T cells in CIA-induced mice. Our research highlights the role of CRMP2 phosphorylation in CD4⁺ T-cell behavior, spinal infiltration, and pain modulation, suggesting potential novel therapeutic strategies for RA-associated chronic pain.

Background: Decidualization deficiency is a key pathological feature of pre-eclampsia (PE) and is closely associated with aberrant regulation of cell fate. PANoptosis is a recently characterized form of inflammatory programmed cell death that has been implicated in several pregnancy-related disorders. However, its potential involvement in decidualization deficiency in PE remains poorly understood. This study aimed to explore the association between PANoptosis-related genes and decidualization deficiency in PE, and to identify candidate biomarkers and potential therapeutic targets related to PANoptosis. Methods: Datasets containing decidual tissue samples derived from women with PE and normal controls were acquired in the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified and subjected to enrichment analysis. After that, PANoptosis-related genes were intersected with DEGs derived from the decidual tissue of PE, followed by protein–protein interaction (PPI) network construction and correlation analysis. Next, the immune infiltration landscape and its association with PANoptosis-related DEGs were assessed. Furthermore, three machine learning algorithms, including support vector machine-recursive feature elimination (SVM-RFE), the least absolute shrinkage and selection operator (LASSO), and the random forest (RF) algorithms, were adopted to identify potential diagnostic biomarkers for PE. Artificial neural network (ANN) and nomogram models were then constructed and evaluated in testing datasets, which included decidual stromal cell samples derived from women with PE and normal controls. Additionally, the expression of PANoptosis-related signature genes and decidualization-related markers was experimentally validated in primary human decidual stromal cells (HDSCs) derived from PE patients and healthy controls. In addition, consensus clustering analysis was conducted on the basis of signature genes, and immune infiltration landscape analysis of different subtypes of PE was performed. Ultimately, the candidate compounds targeting the signature genes were screened and then further verified in vivo and in vitro models. Results: 430 DEGs were determined, and enrichment analysis indicated that these DEGs were mainly involved in inflammation, apoptosis, and dysfunction of decidual tissue in PE. Then, 10 PANoptosis-related DEGs in PE were further screened. Following that, immune landscape analysis revealed an aberrant abundance of various immunocytes and the levels of immune checkpoints in the decidual tissue of PE, which were closely associated with the PANoptosis-related DEGs. Next, through machine learning, nine PANoptosis-related signature genes ( MAPK3 , RIPK1 , RIPK3 , PYCARD , BAX , TUG1 , CDK1 , MAPK1 , and TAB2 ) were identified with favorable predictive performance. Besides, the ANN and nomogram models were constructed, and demonstrated high discriminative ability in the training dataset (AUC = 0.999, 95% CI: 0.995–1.000). Consistently, validation in primary HDSCs derived from PE patients and healthy controls confirmed dysregulated expression of these signature genes, accompanied by reduced decidualization markers ( PRL , IGFBP1 ). Furthermore, on the basis of the analysis of nine signature genes, two different subtypes of PE were acquired, in which subtype B showed an immune hyperactivity state compared to subtype A. Furthermore, melatonin was identified as a candidate compound targeting PANoptosis-related genes and showed protective effects in vivo and in vitro , including improved blood pressure, reduced proteinuria, partial restoration of decidualization markers (PRL, IGFBP1, and F-actin), and declined expressions of PANoptosis-related signature genes (BAX, MAPK1, and MAPK3). Importantly, functional experiments demonstrated that MAPK3 knockdown markedly attenuated PANoptosis-associated inflammatory cytokine production, reduced BAX expression, and partially restored F-actin organization and decidualization markers under PANoptosis-inducing conditions. Conclusion: This study suggests a potential association between PANoptosis-related molecular dysregulation and decidualization deficiency in PE. The identified PANoptosis-related signature genes may serve as candidate biomarkers with predictive relevance, and melatonin may represent a potential therapeutic candidate targeting PANoptosis-related pathways. These findings provide a foundation for future mechanistic and translational studies on PE.

Previous studies to date have demonstrated a significant relationship between spontaneous abortion (SA) and rheumatoid arthritis (RA). Moreover, positive links between gut microbiota and SA, RA have been discussed in observational studies. However, observational studies are prone to bias and result in the causality between gut microbiota and the comorbidity of SA and RA remaining unclear. We therefore aimed to investigate this using a two-sample Mendelian randomization study. A total gut microbiota-related sample size of 18,340 participants from genome-wide association studies was obtained. The summary statistics data for SA (98,453 subjects) and RA (1,53,457 subjects) were obtained from the MRC integrative epidemiology unit genome-wide association studies database as the outcome of gut microbiota. Inverse variance weighted, weighted median, weighted mode, MR-Egger and simple mode were used to assess the causal effects. Sensitivity analyses were applied using the Cochran’s Q -statistic, MR-Egger, the leave-one-out analysis, and Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO). In addition, the statistical power was calculated to evaluate the cause-and-effect. We identified genus Alloprevotella as a shared protective factor for both SA (odds ratio [OR] = 0.903, 95% CI: 0.817–0.997, P = .043) and RA (OR = 0.826, 95% CI: 0.722–0.945, P = .005). In addition, increased abundance of genera Actinomyces (OR = 1.213, 95% CI: 1.025–1.435, P = .025), Subdoligranulum (OR = 1.208, 95% CI: 1.036–1.408, P = .016), and Veillonella (OR = 1.167, 95% CI: 1.003–1.358, P = .046) was causally associated with a higher risk of SA. For RA, decreased abundance of genera ChristensenellaceaeR (OR = 0.736, 95% CI: 0.570–0.950, P = .018), Enterorhabdus (OR = 0.806, 95% CI: 0.684–0.950, P = .010), Prevotella7 (OR = 0.895, 95% CI: 0.808–0.991, P = .032) and Hungatella (OR = 0.818, 95% CI: 0.691–0.970, P = .021), along with increased abundance of the Ruminococcus gauvreauii group (OR = 1.406, 95% CI: 1.112–1.777, P = .004), was linked to elevated disease risk. Sensitivity analyses, including MR-PRESSO, MR-Egger, and Cochran’s Q -statistic, revealed no evidence of heterogeneity or pleiotropy. Furthermore, leave-one-out analysis confirmed the robustness of the causal estimates. Our study identified several gut microbiota genera with putative causal effects on SA (4 genera) and RA (6 genera). Notably, Alloprevotella emerged as a shared protective factor for both conditions. These findings suggest that gut microbiota, particularly Alloprevotella , may play a causal, protective role in the shared etiology of SA and RA, highlighting a potential common therapeutic target for future research and clinical management.