Lupus nephritis: new progress in diagnosis and treatment

Receptor interacting protein kinase 1 activation and triggering mesangial cells necroptosis in MRL/lpr mice model of lupus nephritis

Lupus nephritis (LN) is the most common complication of systemic lupus erythematosus (SLE) affecting the kidneys. Receptor-interacting protein kinase 1 (RIPK1) is involved in necroptosis and inflammatory signaling. Here, we investigate the role of RIPK1 kinase activity in the pathogenesis of LN. Immunofluorescent colocalization of necroptosis with podocyte, endothelial cells, and mesangial cells was detected in the kidney of MRL/lpr mice. In vivo studies used ZJU37 (a RIPK1 inhibitor) to treat MRL/lpr mice to evaluate LN pathological alterations. In vitro, mouse mesangial cells were stimulated with DMSO, serum from MRL/lpr mice, and serum + ZJU37 to detect cell viability, cell death status, expression of necroptosis-related molecular proteins, and significant pathway alterations accompanied by necroptosis. We also conducted functional assay to validate the biological significance of the pathway changed. Firstly, the involvement of RIPK1/RIPK3/MLKL-dependent necroptosis was shown in the mesangial cells of MRL/lpr mice. Secondly, we found that ZJU37 inhibited glomerulonephritis, tubulointerstitial lesions, and vasculitis by reducing the necroptosis of mesangial cells in MRL/lpr mice. Moreover, we discovered that mesangial cells are susceptible to necroptosis when stimulated with serum from MRL/lpr animals and identified the primary altered pathways, including cytokine-cytokine receptor interaction and the PI3K-Akt signaling pathway, which could be abolished by ZJU37. Functional assay showed ZJU37 could significantly increase the migration and cell proliferation ability of mesangial cells. RIPK1 activation triggered mesangial cell necroptosis was identified in the kidneys of MRL/lpr mice and Inhibition of RIPK1 could alleviate LN by reducing the necroptosis of mesangial cells.

Patients with membranous lupus nephritis form two clusters with different prognoses

BACKGROUND AND HYPOTHESIS

Membranous lupus nephritis (MLN) traditionally includes class V (alone), and may be associated with other classes (III or IV). The clinical, therapeutic, and prognostic relevance of the classification remains controversial.

METHODS

A retrospective cohort of 412 MLN patients from the First Affiliated Hospital of Sun-Yat Sen University was followed for a median of 65.68 (interquartile range 23.13-131.70) months. The primary outcomes were adverse renal events including all-cause death and ESRD. Phenotypes were identified and validated using unsupervised clustering analysis (K-means), principal component analysis and decision tree analysis.

RESULTS

Distinct clinical and pathological differences were noted between the traditional class IV + V and classes V + III and V, while class V + III and class V exhibited high similarities in clinical features and prognosis (P = 0.074). K-means clustering revealed high-risk (n = 180) and low-risk (n = 232) groups, with significant differences in adverse renal outcomes (9.2% vs 4.1%, P < 0.001). To recognize the high-risk profile of MLN patients, a decision tree based on Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, hemoglobin, serum creatinine, traditional classification, and activity index of renal biopsy accurately clustered patients in the development (95.8% accuracy) and validation (87.1% accuracy) cohorts.

CONCLUSIONS

Two novel phenotypic clusters, more predictive than traditional classifications, enhance high-risk profile identification and prognostic accuracy.

Urinary MCP-1 and VCAM-1 as non-invasive biomarkers for the diagnosis and activity assessment of lupus nephritis

INTRODUCTION

Accurate diagnosis of lupus nephritis (LN) and effective assessment of its disease activity are essential for optimal management. This study aimed to evaluate the potential of novel urinary biomarkers, MCP-1 and VCAM-1, in diagnosing and assessing LN activity, comparing their efficacy to traditional urinary biomarkers, and proposing a new standard for clinical application.

METHODS

A total of 55 LN patients who met the 1997 ACR diagnostic criteria for systemic lupus erythematosus (SLE) and 34 healthy controls (HCs) were included in this study. The LN patients were categorized into two groups based on their SLE disease activity indices (SLEDAI): the inactive lupus nephritis (NALN) group (SLEDAI 0-4, n = 32) and the active lupus nephritis (ALN) group (renal SLEDAI ≥ 4, n = 22). Additionally, the patients were further classified into mild (SLEDAI 5-9), moderate (SLEDAI 10-14), and severe (SLEDAI > 14) subgroups. All LN patients underwent testing for urinary MCP-1 (uMCP-1), urinary VCAM-1 (uVCAM-1), urinary α1-microglobulin (u-α1MG), urinary β2-microglobulin (u-β2MG), urinary IgG (u-IgG), and urinary albumin (u-ALB), as well as a percutaneous renal biopsy.

RESULTS

The levels of urinary MCP-1 and VCAM-1 (uMCP-1 and uVCAM-1) in the LN group were significantly elevated compared to the HCs (uMCP-1: P < 0.001; uVCAM-1: P < 0.01). Receiver operating characteristic (ROC) curve analysis revealed that the diagnostic efficacy of uMCP-1 and uVCAM-1 surpassed that of traditional biomarkers (uMCP-1: AUC = 0.79, P < 0.001; uVCAM-1: AUC = 0.77, P < 0.001). Multivariate logistic regression demonstrated a significant association between uMCP-1 and uVCAM-1 levels and the occurrence of LN (P < 0.001). Furthermore, these novel biomarkers exhibited stronger correlations with SLEDAI scores than traditional biomarkers (P < 0.001). Notably, patients with ALN had significantly higher levels of uMCP-1 and uVCAM-1 compared to those with NALN (uMCP-1: P < 0.01; uVCAM-1: P < 0.01).

CONCLUSION

The production of uMCP-1 and uVCAM-1 is closely associated with the onset and progression of LN (ISN/RPS: Class I - IV). These biomarkers may serve as valuable references for the diagnosis and prediction of LN and aid in the assessment of LN activity.

Clinical characteristics, prognosis, and predictive modeling in class IV ± V lupus nephritis

Objective

The objective of this study is to compare the clinical features and survival outcomes of class IV ± V lupus nephritis (LN) patients, identify risk factors, and develop an accurate prognostic model.

Methods

This study enrolled patients diagnosed with class IV ± V LN by renal biopsy at Xijing Hospital from December 2013 to June 2023. The composite endpoint of the study was defined as a decline in the estimated glomerular filtration rate (eGFR) by more than 50%, progression to end stage renal disease, or death, whichever came first. The eGFR was calculated utilizing the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. ESRD is defined as an eGFR less than 15ml/min/1.73m2, necessitating the commencement of chronic dialysis (hemodialysis or peritoneal dialysis) or kidney transplantation. We compared the baseline features and survival prognosis between patients with class IV ± V LN. The prognostic model was developed using machine learning algorithms and Cox regression. The model's performance was evaluated in terms of discrimination, calibration, and risk classification using the concordance index (C-index), integrated brier score (IBS), net reclassification index (NRI), and integrated discrimination improvement (IDI), respectively.

Results

A total of 313 patients were enrolled for this study, including 156 class IV and 157 class IV+V LN. During the median follow-up period of 42.6 (17.0, 83.4) months, 35 (22.4%) class IV and 38 (24.2%) class IV+V LN patients experienced combined events. Class IV and class IV+V patients have similar clinical manifestations, treatment strategies, and long-term prognosis, despite class IV having a higher chronic index (CI) score (P < 0.001). Seven eligible variables (eGFR, CI, age, basophil percentage, red blood cell count, mean arterial blood pressure, and uric acid) were selected to develop the random survival forest (RSF) model. This model demonstrated the best performance with a C-index of 0.771 (0.667, 0.848) and an IBS of 0.144 (0.132, 0.154). The IDI and NRI in the testing set further confirmed that the RSF model exhibited superior risk classification and discrimination capabilities.

Conclusion

Class IV ± V LN was similar in clinical manifestations, treatment strategies, and long-term prognosis, despite differences in pathological features. The RSF model we established for class IV ± V LN patients, incorporating seven risk factors, exhibits superior survival prediction and provides more precise prognostic stratification.

Efficacy and safety of telitacicept in patients with class III-V lupus nephritis: A real-world retrospective cohort study

OBJECTIVES

This retrospective cohort study evaluated the efficacy and safety of telitacicept combined with standard therapy in class III-V lupus nephritis (LN).

METHODS

We enrolled 146 patients with lupus nephritis confirmed by renal biopsy. Among them, 73 patients received treatment with telitacicept in combination with the standard therapy regimen, while the remainder were treated with the standard therapy alone. This analysis included class III/IV ± V or class V LN. Efficacy endpoints included cumulative complete renal response (CRR, 24hUTP < 0.5 g with stable renal function) and partial renal response (PRR, 50 % reduction in 24hUTP from baseline) at 6 months, 1 year, and the end of follow-up. Multivariate regression was used to assess baseline predictors of CRR. Safety was also evaluated.

RESULTS

Compared with the control group, telitacicept showed remarkable efficacy in improving disease activity indicators such as serum albumin (ALB), complement levels, and 24-h urinary total protein (24hUTP), with a significant reduction in antibody positivity rates and immunoglobulin levels, alongside an improvement in anemia. By 6 months, the CRR rate in the telitacicept group reached 64.4 % (64.4 % vs 45.2 %, P = 0.020). At 1 year, the cumulative CRR was significantly higher in the telitacicept group compared to the control group (80.8 % vs 61.6 %; P = 0.010). During follow-up, the time to achieve CRR was significantly earlier in the telitacicept group (median 4.0 months, 95 %CI, 2.71-5.29) than in the control group (median 9.0 months, 95 %CI, 5.25-12.75) (LogRank P = 0.006). Moreover, subgroup analyses indicated better efficacy of telitacicept in patients with positive dsDNA antibodies (OR, 1.70, 95 %CI, 1.20-2.40, P for interaction = 0.031). Telitacicept dose reduction did not increase disease activity. Multivariate analysis showed that the use of telitacicept was a favorable factor for achieving CRR, and other predictors included BMI, eGFR, and 24hUTP. Compared with the standard treatment group, the risk of adverse renal outcome events in the telitacicept group was reduced by 53 %. The incidence of adverse events was similar between the two groups.

CONCLUSIONS

This real-event study confirmed that the addition of telitacicept to standard therapy significantly boosted clinical remission rates and improved prognosis in patients with LN. It was also found that telitacicept may be more likely to achieve CRR in dsDNA antibody-positive patients. At baseline, the use of telitacicept, lower BMI and 24hUTP levels, and higher eGFR levels were associated with a greater likelihood of achieving CRR. In addition, for patients who achieve CRR and SLEDAI score ≤ 6, we advocate dose reduction of telitacicept after 6 months of treatment.

Phlorizin attenuates lupus nephritis via upregulating PI3K/Akt pathway-mediated Treg differentiation

BACKGROUND

Lupus nephritis (LN) leads to widespread kidney damage and nephron loss, establishing it as a major contributor to acute and chronic kidney injury, which can progress to end-stage renal disease. Phlorizin (PHZ), a major pharmacologically active constituent derived from Lithocarpus polystachyus Rehd., has been shown to exhibit significant immunomodulatory and anti-inflammatory properties. Growing evidence indicates that PHZ may exert a protective influence on kidney function. However, the therapeutic effect and mechanism of PHZ in treating LN need to be elucidated.

METHODS

The PHZ-associated targets were identified through tools such as PharmMapper, SwissTargetPrediction, SuperPred and Targetnet. Simultaneously, LN-associated target spots were retrieved fromOMIM, DisGeNET, GeneCards, and GEO databases. Additionally, Venny 2.1.0 was employed to analyze the overlap between drug targets and disease targets. Following this, the DAVID software was employed to perform enrichment analyses for GO terms and KEGG pathways on the shared drug-disease target sites. Following this, the construction of protein-protein interaction (PPI) networks for these intersecting targets was carried out using the STRING database and Cytoscape software, aiming to pinpoint critical targets. Ultimately, molecular docking alongside dynamic simulations was used to evaluate the binding affinity between PHZ and the critical genes. Based on these findings, PHZ or Dexamethasone (DXSM) was administered to female MRL/lpr mice, which are predisposed to lupus. The therapeutic effects of PHZ on LN were evaluated by assessing renal function and the degree of kidney inflammation. Concurrently, flow cytometry was employed to measure the percentage of CD4+ T cell subsets. Additionally, relevant signaling pathways were examined through western blot analysis. Furthermore, CD4+CD25+Foxp3+ regulatory T (Treg) cells were induced in vitro. Flow cytometry and immunoblotting were performed to confirm the role and mechanism of PHZ in Treg cell differentiation.

RESULTS

The PHZ compound specifically targeted 161 genes associated with LN. PPI analysis revealed that among all the target genes, Akt1, ALB, MMP9, HSP90AA1, and NF-κB1 exhibited the highest centrality. KEGG pathway analysis suggested that the phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT) signaling pathway could play a crucial role in the treatment of LN. Molecular docking revealed that PHZ exhibits a strong affinity for binding with AKT1. Experimental studies, both in vitro and in vivo, showed that PHZ might alleviate LN by promoting Treg differentiation via activation of the PI3K/AKT signaling pathway.

CONCLUSIONS

Integrating network pharmacology, bioinformatics, and experimental validation, our study systematically deciphers the therapeutic efficacy and molecular mechanisms of PHZ against LN. Network pharmacology analysis and bioinformatics suggested PI3K/AKT signaling as the pivotal pathway to treat LN, while subsequent in vivo and in vitro experiments confirmed that PHZ exerts its therapeutic effects through activating the PI3K/AKT signaling pathway, ultimately driving FOXP3-dependent regulatory T cell differentiation.

Identification of serum exosomal miRNA biomarkers in patients with lupus nephritis

INTRODUCTION

Characterized by glomerulonephritis, lupus nephritis (LN) worsens the prognosis of patients with systemic lupus erythematosus (SLE) and contributes to its increased mortality rate. Here, we investigated whether serum exosomal microRNAs (miRNAs) are promising new biomarkers of LN.

METHODS

Serum exosomes were initially isolated using a reagent-based kit, and total RNA was extracted with the Trizol method. Small RNA sequencing was subsequently performed to identify differentially expressed exosomal miRNAs. Validation of these miRNAs was conducted via real-time quantitative polymerase chain reaction (RT-qPCR) on individual samples from both the training and validation cohorts, leading to the identification of candidate small RNAs specifically associated with LN. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic performance of the identified candidates. To further investigate the immune landscape, 12 types of cytokines were quantified using flow cytometry, and their correlations with the candidate miRNAs were analyzed via Spearman rank correlation. Additionally, the biological functions of these miRNAs were explored through enrichment analyses based on Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways.

RESULTS

The levels of hsa-miR-497-5p and hsa-miR-6515-5p were significantly higher in the LN group compared to the SLE without LN group, with a combined area under the ROC curve (AUC) of 0.798. Notably, these two miRNAs demonstrated exceptional discriminative performance in identifying LN patients with mild proteinuria, achieving an AUC of 0.844. Furthermore, flow cytometry analysis revealed markedly elevated serum levels of interferon (IFN)-γ, interleukin (IL)-8, and IL-17 in the LN group compared to healthy controls (HCs). Additionally, IL-6 and IL-17 levels were significantly higher in the LN group compared to the SLE without LN group. Hsa-miR-6515-5p exhibited a strong positive correlation with IL-8 and IFN-γ. Bioinformatic analyses indicated that these exosomal miRNAs may contribute to the progression of LN by regulating key signaling pathways, with the MAPK signaling pathway being prominently implicated.

CONCLUSIONS

Our study demonstrated that serum exosomal miRNAs, specifically hsa-miR-497-5p and hsa-miR-6515-5p, show significant potential as biomarkers for the early detection and prognosis of LN.

Efficacy and safety of belimumab in refractory and newly diagnosed active lupus nephritis patients: a real-world observational study

Background

Lupus nephritis (LN), one of the common manifestations of systemic lupus erythematosus, continues to be a principal cause of morbidity and mortality. According to the 2024 Kidney Disease: Improving Global Outcomes guidelines, belimumab has been recommended as adjunct therapy for active LN. However, the differences in its efficacy and safety between refractory and newly diagnosed active LN are unknown. This study aimed to evaluate them in a real-world clinical setting in China.

Methods

We enrolled active LN patients who initiated belimumab as adjunct therapy in our centre between June 2021 and January 2024 and divided them into a refractory group and a newly diagnosed group according to previous immunosuppressive therapy. They were followed up for ≥3 months. Renal manifestations, serologic features, Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score and steroids dosage were recorded. We used generalized estimating equations to compare time series data for each group and analyse the change tendency of variables over time. Efficacy endpoints were complete renal response (CRR) and primary efficacy renal response (PERR). Logistic regression models were used to analyse factors associated with renal response.

Results

Of 116 LN patients receiving belimumab in our centre, a total of 89 active LN patients were included in the analysis, with a median treatment duration of 13 months (range 7-22). Among them 47 were in the newly diagnosed group and 42 were in refractory group. At the initiation of belimumab there is no statistical difference in age, gender, SLEDAI-2K score, renal-related markers (proteinuria, serum albumin, estimated glomerular filtration rate and renal histological classification) and serologic features (positive anti-double-stranded DNA, C3, C4) between the two groups. Compared with refractory patients, newly diagnosed patients had significantly shorter LN duration (P < .001) and a larger dosage of steroids (P < .01). During the follow-up period, proteinuria, SLEDAI-2K score and dosage of steroids decreased overall and in each group. The decrease was significantly more pronounced in the newly diagnosed group (P < 0.01, P < 0.001, P < 0.001). For the refractory active LN patients, the estimated probability of CRR and PERR at 12 months was 58.3% and 65.4%, respectively, which was comparable to newly diagnosed patients by logrank test (P = .10, P = .51). No difference was found in adverse event rates (P = .08), time to first renal flare (P = .79) or renal-related events (P = .77). Proteinuria levels at belimumab initiation [odds ratio (OR) 1.306, P = .02] and belimumab treatment duration (OR 0.896, P = .01) were independently associated with renal response.

Conclusion

Compared with refractory LN patients, the add-on treatment with belimumab provides remarkable improvement in newly diagnosed active LN patients, with faster steroids decrease. Our data support the efficacy of early introduction of belimumab in Chinese active LN patients in a real-life setting.

Therapeutic progress in the targeting of B cells in lupus nephritis: pathogenesis to clinical research

Lupus nephritis (LN) is a common complication in patients with systemic lupus erythematosus (SLE), where the key mechanism is the deposition of immune complexes in the kidneys, leading to renal damage. B lymphocytes play a crucial role in the pathogenesis of lupus nephritis through several pathways. These include the production of autoantibodies, which contribute to the deposition of immune complexes in the kidneys, activation of the complement system, and promotion of local inflammatory responses. Additionally, B cells act as antigen-presenting cells, facilitating T cell activation, and secrete proinflammatory cytokines that further exacerbate inflammation. Moreover, an imbalance in B cell subpopulations can worsen autoimmune damage, highlighting the complex role of B cells in the progression of LN. Targeting B cells has emerged as a promising therapeutic strategy, particularly for patients with relapsed or refractory LN. Recent advances in B cell-targeted therapies have shown significant clinical potential, offering new hope for better disease management. This review highlights the latest progress in B cell-targeted approaches for LN treatment and explores their potential to revolutionize care for this challenging condition.

Sirt1 protects lupus nephritis by inhibiting the NLRP3 signaling pathway in human glomerular mesangial cells

Lupus nephritis (LN) is the most common and lethal complication of systemic lupus erythematosus. We aimed to explore the protective effect of Sirtuin1 (Sirt1) on LN by regulating the NLRP3 signaling pathway in human glomerular mesangial cells (GMCs). We collected clinical samples from patients with LN, detected Sirt1 protein and mRNA expression using biochemical methods, cultured GMCs in vitro, evaluated levels of oxidative stress, cell apoptosis, and mitochondrial damage, and analyzed the expression of NLRP3 pathway proteins. Our results demonstrated that Sirt1 protein and mRNA were downregulated in the renal tissue of LN patients, and LN serum induced an increase in oxidative stress, cell apoptosis, and mitochondrial damage in GMCs while activating the NLRP3 signaling pathway. Upregulation of Sirt1 inhibited LN serum-induced oxidative stress in GMCs, reduced the number of cell apoptosis, and stabilized mitochondrial structure and function. Moreover, Sirt1 overexpression inhibited the expression of NLRP3 pathway proteins. Our findings suggest that Sirt1 may protect LN by inhibiting the NLRP3 signaling pathway in GMCs.

Mesenchymal stromal cells reduce ferroptosis of podocytes by activating the Nrf2/HO-1/GPX4 pathway in lupus nephritis

BACKGROUND

Ferroptosis has been reported to be involved in the occurrence and development of various kidney diseases. Emerging evidence suggests that ferroptosis also plays a critical role in systemic lupus erythematosus (SLE) and lupus nephritis (LN), contributing to podocyte injury and renal dysfunction. Mesenchymal stromal cells (MSCs) have become an attractive option for podocyte injury repairing in LN. The aim of this research was to determine whether MSCs regulate ferroptosis of podocytes in LN.

METHODS

MSCs were injected into female MRL/lpr mice via tail vein. The symptoms of LN and the detection of ferroptosis-related biomarkers in podocytes were detected. In vitro validation was conducted by mouse podocyte cell line MPC-5.

RESULTS

The occurrence of ferroptosis and involvement of Nrf2/heme oxygenase-1 (HO-1) signaling pathway in podocytes were observed. We found increased expression of the podocyte marker, Wilm's tumor 1 (WT-1) and synaptopodin, following the improvement of lupus-like symptoms after MSC transplantation in MRL/lpr mice. The expression of ferroptosis-related protein glutathione peroxidase 4 (GPX4) and long chain acyl-CoA synthetase 4 (ACSL4) were elevated in renal, along with the Nrf2 and HO-1 activity enhancement. In vitro, MSC treatment maintain a stabilization of podocyte actin stress fibers, leading to an improvement of cell viability. Furthermore, our results showed that puromycin aminonucleoside (PAN) induce accumulation of cellular lipid reactive oxygen species (ROS) and glutathione depletion, and the expression of Nrf2, HO-1 and GPX4 were all downregulated whereas the expression of ACSL4 was upregulated. However, these effects were reversed by MSCs and ferroptosis inhibitor ferrastatin-1 (Fer-1). The promotion of Nrf2 nuclear translocation was observed after the treatment with MSCs.

CONCLUSION

Ferroptosis activation is involved in the development of LN. MSCs could ameliorate podocyte injury in LN by inhibiting ferroptosis through the Nrf2/HO-1/GPX4 pathway, which will provide novel potential therapeutic targets for LN.

Proteomics uncovers ICAM2 (CD102) as a novel serum biomarker of proliferative lupus nephritis

OBJECTIVES

This study aimed to identify novel, non-invasive biomarkers for lupus nephritis (LN) through serum proteomics.

METHODS

Serum proteins were detected in patients with LN and healthy control (HC) groups through liquid chromatography-tandem mass spectrometry. The key networks associated with LN were screened out using Cytoscape software, followed by pathway enrichment analysis. The best candidate biomarkers were selected by machine learning models, further validated in a larger independent cohort. Finally, the expression of these candidate markers was verified in kidney tissue samples, and the mechanism was explored by knocking down the expression of intercellular adhesion molecule 2 (ICAM2) through in vitro cell transfection with siRNA.

RESULTS

Following the serum proteomic screening of LN, a key network of 20 proteins was identified. Machine learning models were used to select ICAM2 (CD102), metalloproteinase inhibitor 1 (TIMP1) and thrombospondin 1 (THSB1) for validation in independent cohorts. ICAM2 exhibited the highest area under the curve (AUC) value in distinguishing LN from HC (AUC=0.92) and was significantly correlated with activity index, proteinuria, albumin and anti-dsDNA antibody levels. Particularly, ICAM2 was significantly elevated in proliferative LN and was associated with specific pathological attributes, outperforming conventional parameters in distinguishing proliferative LN from non-proliferative LN. ICAM2 expression was also elevated in renal tissue samples from patients with proliferative LN. In vitro, knockdown of ICAM2 expression can inhibit the activation of the PI3K/Akt pathway and alleviate the injury of glomerular endothelial cells.

CONCLUSION

ICAM2 (CD102) may serve as a potential serum biomarker for proliferative LN that reflects renal pathology activity, potentially contributing to the progression of LN through the PI3K/Akt pathway.

Effects of remnant cholesterol on adverse renal outcomes in lupus nephritis

BACKGROUND

Remnant cholesterol (RC) causes inflammation and promotes kidney diseases development. However, its role in lupus nephritis (LN) remains unclear. The purpose of this study was to investigate the association between RC and LN.

METHODS

This observational study was conducted among patients enrolled between 2000 and 2018 in the High Quality Evidence of Guangzhou Lupus Nephritis Cohort. The study outcomes were defined as adverse renal outcomes, including serum creatinine doubled and end-stage renal disease. Patients were stratified into lower and higher RC groups based on the optimal cutoff RC value (86.88 mg/dL) for adverse renal outcomes. To explore the association between renal outcomes and RC, survival analyses, multivariate Cox regression analyses, and subgroup analyses were conducted.

RESULTS

Overall, 909 individuals were enrolled. Over a median follow-up of 8.33 (interquartile range, 3.08-12.83) years, 134(14.74%) of them reached renal endpoints. Kaplan-Meier survival analyses indicated that patients with higher RC levels were more susceptible to adverse renal outcomes in LN (P < 0.001). After adjusting for confounding factors, higher RC levels exhibited significant correlations with adverse renal outcomes in LN [hazard ratio (HR):1.98, 95% confidence interval (CI):1.16-3.39; P = 0.012]. Subgroup analyses revealed a strong relationship between the higher RC and adverse renal outcomes, particularly in patients aged < 40 years, with an estimated glomerular filtration rate < 60 ml/min/1.73m2 or proliferative pathological changes or nephrotic syndrome (P < 0.05).

CONCLUSIONS

Higher RC levels were significantly associated with poor renal outcomes in LN, indicating that RC may become a non-invasive prognostic tool in clinical assessment of LN.

Machine Learning-Based Identification of Novel Exosome-Derived Metabolic Biomarkers for the Diagnosis of Systemic Lupus Erythematosus and Differentiation of Renal Involvement

OBJECTIVE

This study aims to investigate the exosome-derived metabolomics profiles in systemic lupus erythematosus (SLE), identify differential metabolites, and analyze their potential as diagnostic markers for SLE and lupus nephritis (LN).

METHODS

Totally, 91 participants were enrolled between February 2023 and January 2024 including 58 SLE patients [30 with nonrenal-SLE and 28 with Lupus nephritis (LN)] and 33 healthy controls (HC). Ultracentrifugation was used to isolate serum exosomes, which were analyzed for their metabolic profiles using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Endogenous metabolites were identified via public metabolite databases. Random Forest, Lasso regression and Support Vector Machine Recursive Feature Elimination (SVM-RFE) algorithms were employed to screen key metabolites, and a prediction model was constructed for SLE diagnosis and LN discrimination. ROC curves were constructed to determine the potential of these differential exosome-derived metabolites for the diagnosis of SLE. Furthermore, Spearman's correlation was employed to evaluate the potential links between exosome-derived metabolites and the clinical parameters which reflect disease progression.

RESULTS

A total of 586 endogenous serum exosome-derived metabolites showed differential expression, with 225 exosome-derived metabolites significantly upregulated, 88 downregulated and 273 exhibiting no notable changes in the HC and SLE groups. Machine learning algorithms revealed three differential metabolites: Pro-Asn-Gln-Met-Ser, C24:1 sphingolipid, and protoporphyrin IX, which exhibited AUC values of 0.998, 0.992 and 0.969 respectively, for distinguishing between the SLE and HC groups, with a combined AUC of 1.0. In distinguishing between the LN and SLE groups, the AUC values for these metabolites were 0.920, 0.893 and 0.865, respectively, with a combined AUC of 0.931, demonstrating excellent diagnostic performance. Spearman correlation analysis revealed that Pro-Asn-Gln-Met-Ser and protoporphyrin IX were positively correlated with the SLE Disease Activity Index (SLEDAI) scores, urinary protein/creatinine ratio (ACR) and urinary protein levels, while C24:1 sphingolipid exhibited a negative correlation.

CONCLUSIONS

This study provides the first comprehensive characterization of the exosome-derived metabolites in SLE and established a promising prediction model for SLE and LN discrimination. The correlation between exosome-derived metabolites and key clinical parameters strongly indicated their potential role in SLE pathological progression.

Dimethyloxallyl Glycine Preconditioning Promotes the Anti-inflammatory and Anti-fibrotic Effects of Human Umbilical Cord Mesenchymal Stem Cells on Kidney Damage in Systemic Lupus Erythematosus Related to TGF-β/Smad Signaling Pathway

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease lacking effective treatments without adverse effects. Dimethyloxallyl glycine (DMOG) enhanced mesenchymal stem cells (MSC) capabilities, but it remains unclear how DMOG-pretreatment of MSCs augments their SLE treatment. Here, we explore the therapeutic potential of DMOG-pretreated human umbilical cord MSCs (hUC-MSCs) in a mouse lupus nephritis (LN) model. In vitro experiments showed that DMOG could alleviate the mRNA levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-6 and increase the mRNA level of IL-13 in lipopolysaccharide (LPS)-induced inflammation in hUC-MSCs. DMOG enhanced the migratory and invasive abilities of the hUC-MSCs. In vivo animal studies revealed that DMOG-pretreated hUC-MSCs exhibited more pronounced inhibition of lymphadenectasis and reduced kidney weight and urinary protein content than MSCs alone. DMOG-pretreated hUC-MSCs improved renal morphological structure and alleviated inflammatory cell infiltration and renal fibrosis, evidenced by the reduced mRNA levels of fibrosis markers, including fibronectin (Fn), collagen alpha-1 chain (Colα1), collagen alpha-3 chain (Colα3), and TNF-α, IFN-γ, and IL-6 cytokines. Further investigation revealed that DMOG-pretreated hUC-MSCs down-regulated the expressions of transforming growth factor (Tgf)-β1 and its downstream effectors Smad2 and Smad3, recognized as central mediators in renal fibrosis (P < 0.05). The findings suggest that DMOG-pretreated hUC-MSCs can augment the therapeutic efficacy of hUC-MSCs in LN by enhancing their anti-inflammatory and antifibrotic effects, and the TGF-β/Smad signaling pathway may be involved in this process.

Lupus Nephritis Revealed by FAPI PET/CT

ABSTRACT

A 38-year-old woman received a 68 Ga-FAPI-04 PET/CT scan for the evaluation of systemic lupus erythematosus. Diffuse uptake in both kidney parenchyma indicated the presence of lupus nephritis. In addition, an incidental carotid body tumor with increased FAPI uptake was also observed. Our case described the imaging features of lupus nephritis coexistent with a carotid body tumor on FAPI PET/CT.

Acute Kidney Injury in Autoimmune-Mediated Rheumatic Diseases

Acute kidney injury (AKI) is increasingly affecting hospitalized patients worldwide. Patients with inflammatory rheumatic diseases, although primarily impacted by functional impairment and sometimes structural damage to joints, bones, and muscle tissue, may also develop AKI during the course of their disease. This narrative review aimed to summarize potential causes of AKI and the associated disease patterns. The following databases were searched for references: PubMed, Web of Science, Cochrane Library, and Scopus. The search period covered from 1958 to 2024. Certain inflammatory rheumatic diseases increase the risk of AKI due to specific types of kidney disease. However, the most common conditions, such as rheumatoid arthritis and spondylarthritis, rarely cause AKI directly. Among the medications used for pain and sometimes disease activity control, nonsteroidal anti-inflammatory drugs (NSAIDs) can potentially induce AKI, even progressing to acute tubular necrosis. There is evidence that certain rheumatic diseases are associated with increased risk of AKI, independently of directly affecting kidney function or structure. However, the data on this topic are quite limited. AKI is a potentially significant issue for patients with inflammatory rheumatic diseases. Additional data on the increased risk of AKI, independent of direct kidney involvement, are needed.

Beyond cancer: The potential application of CD47-based therapy in non-cancer diseases

CD47 is an immune checkpoint widely regarded as a 'don't eat me' signal. CD47-based anti-cancer therapy has received considerable attention, with a significant number of clinical trials conducted. While anti-cancer therapies based on CD47 remain a focal point of interest among researchers, it is noteworthy that an increasing number of studies have found that CD47-based therapy ameliorated the pathological status of non-cancer diseases. This review aims to provide an overview of the recent progress in comprehending the role of CD47-based therapy in non-cancer diseases, including diseases of the circulatory system, nervous system, digestive system, and so on. Furthermore, we sought to delineate the promising mechanisms of CD47-based therapy in treating non-cancer diseases. Our findings suggest that CD47-based agents may exert their effect by regulating phagocytosis, regulating T cells, dendritic cells, and neutrophils, and regulating the secretion of cytokines and chemokines. Additionally, we put forward the orientation of further research to bring to light the potential of CD47 and its binding partners as a target in non-cancer diseases.

Aurora kinase B inhibitor AZD1152: repurposing for treatment of lupus nephritis driven by the results of clinical trials

BACKGROUND

Lupus nephritis (LN) is one of the most common and severe complications of systemic lupus erythematosus (SLE). Multitarget therapy (MT) achieves a 20% higher complete remission (CR) rate compared to conventional therapy in LN management. Intrigued by its excellent clinical efficacy, we aimed to develop a single-agent therapy with comparable efficacy to MT, offering a simplified treatment regimen.

METHODS

AZD1152, an Aurora kinase B (Aurkb) inhibitor, was identified through transcriptomic analyses and the L1000 CMap drug repurposing database. The therapeutic efficacy of AZD1152 was evaluated in MRL/lpr mice. Transcriptome sequencing and functional assays were performed to elucidate its mechanisms of action. Aurkb expression and its clinical relevance were assessed in lupus-prone mice and patients with LN.

FINDINGS

AZD1152 significantly attenuated systemic immune activation and renal injury in MRL/lpr mice, demonstrating efficacy comparable to MT regimens in animal studies. AZD1152 treatment modulated immune-inflammatory pathways in the kidney. Aurkb expression was upregulated in T cells infiltrating the renal interstitium in LN. Additionally, Aurkb expression levels positively correlated with the activity index (AI) and serum creatinine (Scr) in patients with LN. Mechanistic studies revealed that AZD1152 exerts therapeutic effects primarily by inhibiting T-cell proliferation.

INTERPRETATION

This study presents a drug development strategy that integrates clinically validated LN therapies with drug repurposing approaches. This strategy could accelerate drug development and clinical translation processes for LN.

FUNDING

A full list of funding sources can be found in the acknowledgements section.

Efficacy and safety of belimumab in patients with lupus nephritis: a real-world retrospective observational study

OBJECTIVES

To evaluate the differences in efficacy and safety between lupus nephritis (LN) patients who received belimumab plus standard therapy and those who received only standard therapy in real world practice.

METHODS

Patients diagnosed with LN at the First Affiliated Hospital of Wenzhou Medical University from November 2012 to July 2023 were identified, and eligible cases were divided into two groups according to whether they received additional treatment with belimumab during the course of the disease.

RESULTS

A total of 1169 LN patients were identified from our follow-up database. In total, 112 patients receiving add-on treatment with belimumab (BLM group) and 112 control patients matched for relevant baseline characteristics were enrolled in this study. The median duration of treatment with belimumab was 13.82 [7.24, 20.29] months. Compared with the control group, the BLM group had more significant improvement in disease activity indicators such as serum albumin and complement levels, significantly lower B-cell count, immunoglobulin, and earlier first attainment of renal remission, but there was no significant improvement in renal function and kidney-related events or death during the 2-year follow-up period. In the BLM group, the treatment effect of belimumab was more prominent in patients with lower levels of proteinuria. The safety profile of belimumab treatment was favorable, with a lower incidence of respiratory tract infection in the BLM group than in the control group during the follow-up period (P = 0.015).

CONCLUSIONS

This real-world study revealed that add-on treatment with belimumab provided better disease remission, and the therapeutic effect was more significant in patients with lower proteinuria levels. In addition, it had a favorable safety profile and reduced the risk of respiratory tract infection.

Complex Clinical Interplay: A Case Report of Systemic Lupus Erythematosus Coexisting With Type II Cryoglobulinemia

Systemic lupus erythematosus (SLE) is a multi-faceted autoimmune disease with diverse clinical manifestations, often diagnosed through specific immunological markers. Another noteworthy immunological phenomenon associated with SLE is cryoglobulinemia (CG), characterized by circulating immunoglobulins that precipitate at lower temperatures. Although the overlap of SLE and CG is documented, its precise prevalence remains elusive. This paper presents a unique case of a patient diagnosed with lupus cryoglobulinemic glomerulonephritis through biopsy. The patient attained full remission after an initial induction using the Eurolupus protocol complemented with plasmapheresis, with subsequent maintenance therapy managed via rituximab.

Novel approach to alleviate lupus nephritis: targeting the NLRP3 inflammasome in CD8+CD69+CD103+ TRM cells

BACKGROUND

Renal CD8+ tissue-resident memory T (TRM) cells display prolonged survival and activity in lupus nephritis (LN), exacerbating renal pathology. NLRP3 regulates the T cell response. This study explored the impact of NLRP3 inflammasome activity on the regulatory functions of TRM cells in LN.

METHODS

NLRP3 inflammasome activity in renal CD8+ TRM cells from lupus-prone MRL/lpr mice and in vitro induced human CD8+CD103+ T cells was assessed by quantifying NLRP3, caspase-1, gasdermin D (GSDMD), and IL-1β levels using flow cytometry, ELISA, and western blotting analysis. The specific NLRP3 inhibitor MCC950, caspase-1 inhibitor Ac-YVAD-cmk, and NF-κB inhibitor JSH23 were utilized to delineate the role of NLRP3 in modulating the pathogenicity of CD8+ TRM cells in LN.

RESULTS

Activation of the NLRP3 inflammasome was confirmed in renal CD8+CD69+CD103+ TRM cells derived from mice with LN and in vitro-induced human CD8+CD103+ TRM-like cells. MCC950 curtailed the infiltration and activity of CD8+CD69+CD103+ TRM cells and enhanced renal outcomes. MCC950 also suppressed the maturation and functional capabilities of CD8+CD103+ T cells in a manner reliant on inflammasome activity in vitro. IL-1β promoted the expression of TGF-βRII in CD8+ T cells via the NF-κB pathway.

CONCLUSIONS

NLRP3 inflammasome activity in renal CD8+CD69+CD103+ TRM cells contributes to LN pathogenesis by regulating cell differentiation and effector functions. Therapeutically targeting the NLRP3 inflammasome could significantly mitigate CD8+CD69+CD103+ TRM cell-mediated renal damage in LN.

Neutrophil extracellular traps and oxidative stress in systemic lupus erythematosus patients with and without renal involvement

OBJECTIVES

To investigate the levels of plasma neutrophil extracellular traps (NETs) and free thiols, the latter reflecting systemic oxidative stress (OS), and to explore the relationship between NETs and OS in quiescent systemic lupus erythematosus (SLE) patients with and without renal involvement.

METHODS

Plasma levels of NETs and free thiols were measured cross-sectionally in 100 SLE patients with low disease activity (SLEDAI < 5), of whom 73 patients had no renal involvement (non-LN) and 27 patients had lupus nephritis (LN). Additionally, 22 healthy controls (HCs) were included. NETs were measured using a myeloperoxidase-DNA complex ELISA and free thiols were measured using a thiol assay kit.

RESULTS

NETs levels were significantly higher in both non-LN and LN patients compared to HCs (p < 0.001, p = 0.013), with no difference between the two patient groups (p = 0.799). Free thiol levels were not significantly different between groups. Interestingly, NETs were negatively correlated with free thiols in all 100 SLE patients (rho = -0.32) and non-LN patients (rho = -0.38), but not in LN patients. Levels of free thiols were significantly lower in subgroups of patients with estimated glomerular filtration rate (eGFR) < 60, serum creatinine (sCr) ≥ 90, C reactive protein (CRP) levels ≥ 5 and body mass index (BMI) ≥ 30. In multivariable regression, disease duration, NETs levels, and eGFR were independently associated with free thiol levels.

CONCLUSIONS

Levels of NETs were increased in quiescent SLE patients. Although free thiol levels did not differ among the groups. The levels of NETs and free thiols were independently associated in SLE patients, suggesting a potential role of OS in NETs formation. Therefore, reducing OS might be an additional therapeutic target for SLE treatment.

GS-4997 halts the progression of tubulointerstitial injury in lupus nephritis

Tubulointerstitial injury has been increasingly recognized as an important component in lupus nephritis (LN) pathology over the last decades. However, current clinical treatment options for this process remain limited. In this study, we aimed to investigate the potential benefits of GS-4997, a selective inhibitor of ASK1, in tubulointerstitial injury of LN. Female MRL/lpr mice were used as a classical lupus-prone murine model. Development of nephritis was assessed by monitoring of proteinuria, renal function, and histologic analysis. GS-4997 (50 mg/kg) or vehicle were treated orally. In vitro study, human kidney-2 (HK-2) cells were stimulated with 1 μg/mL lipopolysaccharide (LPS) to mimic the response of renal tubular epithelial cells undergoing inflammatory responses during LN. GS-4997 could inhibit the activation of the ASK1 in renal tubulointerstitium in MRL/lpr mice and LPS-induced HK-2 cells. GS-4997 treatment improved renal function, proteinuria, and attenuated tubular injury, renal interstitial fibrosis, and inflammation both in vivo and in vitro. Additionally, we found that in MRL/lpr mice, GS-4997 reduced deposition of IgG and C3 in the kidneys, antibody levels in the serum, splenic enlargement, and inflammatory cell infiltration in the spleen. Mechanistically, GS-4997 inhibited the activation of downstream signaling molecules, p38 and JNK, in the ASK1 signaling pathway. Pharmacological inhibition of ASK1 may prevent the progression of tubulointerstitial injury via inhibiting the ASK1/MAPK pathway in LN. Therefore, our findings demonstrate the potential use of GS-4997 for LN treatment.

Urinary microbiome profiling as a non-invasive tool for identifying biomarkers in systemic lupus erythematosus and lupus nephritis

Introduction

Bacteriome alterations have been implicated in the pathogenesis of systemic lupus erythematosus (SLE). However, the relationship between SLE and the urinary microbiome remains underexplored. This study aimed to characterize the urinary microbiome of SLE patients using 16S rRNA sequencing and to investigate its correlations with clinical parameters through integrative analyses.

Methods

Urine sediment samples were collected from individuals with SLE and lupus nephritis (LN) (n = 20), SLE without LN (n = 22), and healthy controls (HCs) (n = 23). DNA was extracted and subjected to 16S rRNA sequencing to profile the urinary microbiome. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the diagnostic efficacy of urinary microbiota, while Spearman's correlation analysis was employed to identify links between specific microbial taxa and clinical parameters. Functional predictions of bacterial roles were performed using Picrust2.

Results

The urinary microbiota diagnostic model exhibited excellent performance in distinguishing SLE patients from HCs. Spearman's analysis revealed significant correlations between the urinary microbiome and clinical parameters. Specifically, Sphingomonas and Lachnospiraceae genera showed positive correlations with vitamin D levels, cylinderuria, and proteinuria, while Pedobacter, Aquabacterium, Delftia, and Achromobacter displayed negative correlations with proteinuria and albumin-to-creatinine ratio (ACR). Functional predictions indicated that the urinary microbiome might influence immune regulation through modulation of signaling pathways and metabolic processes.

Discussion

Our study is the first to reveal dysbiosis in the urinary microbiome of patients with SLE. Certain bacterial taxa in the urinary microbiome were identified as potential diagnostic biomarkers for SLE. Furthermore, the functional implications of these bacterial communities suggest their involvement in immune modulation, highlighting the potential for further investigation into their roles in SLE pathogenesis and diagnosis.

Chemokines and chemokine receptors: Potential therapeutic targets in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects connective tissue and can lead to multisystem organ damage. Chemokines are a class of small proteins that interact with receptors and participate in a variety of physiological functions, including cell growth, differentiation, apoptosis and distribution. They also play important roles in pathological processes, such as the inflammatory response, wound repair, tumor formation and metastasis. Previous studies have shown that the levels of chemokines and their receptors are elevated in the blood and inflamed tissues of SLE patients. In addition, chemokine ligand-receptor interactions control the recruitment of leukocytes into tissues, suggesting that chemokines and their receptors may be biomarkers and therapeutic targets for SLE. This review summarizes the causative role of chemokines and their receptors in SLE, as well as their clinical values and challenges as potential biomarkers and therapeutic targets.

HDAC6 promotes inflammation in lupus nephritis mice by regulating transcription factors MAFF and KLF5 in renal fibrosis

AIM

This study explored the effect and mechanism of MAFF and HDAC6 on renal fibrosis and inflammation in lupus nephritis (LN).

METHODS

IL-33 treated renal epithelial cells and MRL/lpr mice were respectively used for in vitro and in vivo experiments. The expressions of HDAC6, MAFF, and KLF5 were measured in cells and renal tissues. Before and after cell transfection, the morphological changes in renal tissues were observed using Hematoxylin and eosin (H&E) and Masson staining. The proteinuria, serum creatinine (SCr), blood urea nitrogen (BUN), and double-stranded DNA (dsDNA) levels were detected by biochemical analysis. The expressions of fibrosis and inflammation related proteins (including α-SMA, Vimentin, IL-1β, IL-6, and TNF-α), p65, and iNOS were also detected. The relationship among MAFF, HDAC6, and KLF5 was determined by chromatin immunoprecipitation and dual luciferase reporter gene assay.

RESULTS

Renal tissues and cell models had elevated expressions of HDAC6 and KLF5, and decreased MAFF expression. HDAC6 suppression or MAFF overexpression led to suppression of proteinuria, SCr, BUN, and dsDNA levels, as well as attenuation of inflammatory infiltration and collagen deposition. HDAC6 can suppress MAFF expression via deacetylation to abolish its suppression of KLF5 expression, thus increasing KLF5 expression. In vivo and in vitro experiments showed the suppressive effect of HDAC6 suppression on renal fibrosis and inflammation can be abolished by KLF5 overexpression.

CONCLUSION

HDAC6 suppresses MAFF expression via deacetylation to elevate KLF5 expression, which consequently enhances fibrosis and inflammatory response in LN.

Antagonising Yin Yang 1 ameliorates the symptoms of lupus nephritis via modulating T lymphocyte signaling

Lupus nephritis (LN) is a chronic complication of systemic lupus erythematosus (SLE). At present, no drugs are capable of delaying the progression of LN without a risk of serious side effects. There is thus a pressing need for further studies of LN pathogenesis to identify novel therapeutic targets and aid in the development of new approaches to treating this debilitating disease. In this study, a multi-omics approach was used to characterize the pathogenesis of LN and to identify disease-related targets, ultimately leading to the identification and validation of Yin Yang 1 (YY1) as a promising therapeutic target in LN. A rapid approach to efficiently screening for candidate YY1 ligands was implemented using drug databases that established rebamipide as a YY1 antagonist suitable for use in the management of LN. Specifically, the YY1 antagonist activity of rebamipide was found to regulate lymphocyte activity, reduce autoantibody production, limit immune complex deposition, and suppress macrophage activation while improving symptoms in a murine model of LN. Results supportive of a similar pathologic mechanism of action were also obtained when analyzing renal tissue sections from LN patients, underscoring the potential clinical significance of YY1 and its antagonist rebamipide, suggesting that rebamipide may have positive effects on lymphocytes and may improve symptoms in treated patients. This study provides a robust foundation for further research focused on the pathogenesis and treatment of LN.

Methyltransferase-like 3 represents a prospective target for the diagnosis and treatment of kidney diseases

Kidney disease is marked by complex pathological mechanisms and significant therapeutic hurdles, resulting in high morbidity and mortality rates globally. A deeper understanding of the fundamental processes involved can aid in identifying novel therapeutic targets and improving treatment efficacy. Current comprehensive data analyses indicate the involvement of methyltransferase-like 3 (METTL3) and its role in RNA N6-methyladenosine methylation in various renal pathologies, including acute kidney injury, renal fibrosis, and chronic kidney disease. However, there is a paucity of thorough reviews that clarify the functional mechanisms of METTL3 and evaluate its importance in enhancing therapeutic outcomes. This review seeks to systematically examine the roles, mechanisms, and potential clinical applications of METTL3 in renal diseases. The findings presented suggest that METTL3 is implicated in the etiology and exacerbation of kidney disorders, affecting their onset, progression, malignancy, and responsiveness to chemotherapeutic agents through the regulation of specific genetic pathways. In conclusion, this review underscores a detrimental correlation between METTL3 and kidney diseases, highlighting the therapeutic promise of targeting METTL3. Additionally, it offers critical insights for researchers concerning the diagnosis, prognosis, and treatment strategies for renal conditions.

Oxymatrine Ameliorates Lupus Nephritis by Targeting the YY1-Mediated IL-6/STAT3 Axis

Lupus nephritis (LN) is a severe form of systemic lupus erythematosus (SLE), characterized by inflammation in the renal glomeruli and tubules. Previous research has demonstrated that dihydroartemisinin (DHA) can reduce inflammatory damage in LN mouse models. Oxymatrine, which has similar biological properties to DHA, may also provide therapeutic benefits. This study aims to investigate the effects of oxymatrine on LN using a murine model and examines its molecular mechanisms through an analysis of microarray datasets from LN patients. The analysis identified differentially expressed genes (DEGs) in renal tissues, regulated by the transcription factor Yin Yang 1 (YY1), which was found to be significantly upregulated in LN patient kidneys. The results indicate that oxymatrine targets the YY1/IL-6/STAT3 signaling pathway. In cell models simulating renal inflammation, oxymatrine reduced YY1 expression and inhibited the secretion of inflammatory factors (IFs), thereby diminishing inflammation. YY1 is crucial in modulating IFs' secretion and contributing to LN pathogenesis. Additionally, oxymatrine's interaction with YY1, leading to its downregulation, appears to be a key mechanism in alleviating LN symptoms. These findings support oxymatrine as a promising therapeutic agent for LN, offering new avenues for treating this autoimmune kidney disorder.

Advances in the study of artemisinin and its derivatives for the treatment of rheumatic skeletal disorders, autoimmune inflammatory diseases, and autoimmune disorders: a comprehensive review

Artemisinin and its derivatives are widely recognized as first-line treatments for malaria worldwide. Recent studies have demonstrated that artemisinin-based antimalarial drugs, such as artesunate, dihydroartemisinin, and artemether, not only possess excellent antimalarial properties but also exhibit antitumor, antifungal, and immunomodulatory effects. Researchers globally have synthesized artemisinin derivatives like SM735, SM905, and SM934, which offer advantages such as low toxicity, high bioavailability, and potential immunosuppressive properties. These compounds induce immunosuppression by inhibiting the activation of pathogenic T cells, suppressing B cell activation and antibody production, and enhancing the differentiation of regulatory T cells. This review summarized the mechanisms by which artemisinin and its analogs modulate excessive inflammation and immune responses in rheumatic and skeletal diseases, autoimmune inflammatory diseases, and autoimmune disorders, through pathways including TNF, Toll-like receptors, IL-6, RANKL, MAPK, PI3K/AKT/mTOR, JAK/STAT, and NRF2/GPX4. Notably, in the context of the NF-κB pathway, artemisinin not only inhibits NF-κB expression by disrupting upstream cascades and/or directly binding to NF-κB but also downregulates multiple downstream genes controlled by NF-κB, including inflammatory chemokines and their receptors. These downstream targets regulate various immune cell functions, apoptosis, proliferation, signal transduction, and antioxidant responses, ultimately intervening in systemic autoimmune diseases and autoimmune responses in organs such as the kidneys, nervous system, skin, liver, and biliary system by modulating immune dysregulation and inflammatory responses. Ongoing multicenter randomized clinical trials are investigating the effects of these compounds on rheumatic, inflammatory, and autoimmune diseases, with the aim of translating promising preclinical data into clinical applications.

Neuropilin-1 as a Key Molecule for Renal Recovery in Lupus Nephritis: Insights from an NZB/W F1 Mouse Model

Systemic lupus erythematosus (SLE) is an autoimmune disease affecting multiple organs, with lupus nephritis (LN) occurring in 40-50% of SLE patients. Despite advances in diagnosis and treatment, LN remains a major cause of morbidity and mortality, with 10-20% of patients progressing to end-stage renal disease (ESRD). While knowledge of LN's pathogenesis has improved, mechanisms of renal recovery are still largely unexplored. Neuropilin-1 (NRP-1), a transmembrane receptor expressed in renal tissue, has emerged as a promising biomarker for assessing renal recovery in LN. This study evaluates and correlates longitudinal levels of NRP-1 with kidney histology using an NZB/W F1 mouse model of LN. A total of 30 mice were used, with 15 receiving intravenous cyclophosphamide (CYC) and 15 being untreated. NRP-1 levels were measured in urine and serum, and kidney samples were taken from a subgroup of mice for histological evaluation. The results demonstrated a progressive increase in renal and urinary NRP-1 expression, particularly notable at weeks 26 and 32. Urinary NRP-1 levels above 34.40 ng/mL were strong predictors of favorable renal response, showing 100% sensitivity and 88% specificity. These findings indicate a robust correlation between urinary NRP-1 levels and renal histological recovery, underscoring the potential of NRP-1 as a valuable biomarker for assessing renal response in LN. This study demonstrates that renal production of NRP-1 is linked to histological recovery and establishes a foundation for future research into the role of NRP-1 in lupus kidney recovery.

LncRNA XIST/miR-381-3P/STAT1 axis as a potential biomarker for lupus nephritis

OBJECTIVE

We aim to investigate the potential roles of key genes in the development of lupus nephritis (LN), screen key biomarkers, and construct the lncRNA XIST/miR-381-3P/STAT1 axis by using bioinformatic prediction combined with clinical validation, thereby providing new targets and insights for clinical research.

METHODS

Gene expression microarrays GSE157293 and GSE112943 were downloaded from the GEO database to obtain differentially expressed genes (DEGs), followed by enrichment analyses on these DEGs, which were enriched and analyzed to construct a protein-protein interaction (PPI) network to screen core genes. The lncRNA-miRNA-mRNA regulatory network was predicted and constructed based on the miRNA database. 37 female patients with systemic lupus erythematosus (SLE) were recruited to validate the bioinformatics results by exploring the diagnostic value of the target ceRNA axis in LN by dual luciferase and real-time fluorescence quantitative PCR (RT-qPCR) and receiver operating characteristic (ROC).

RESULTS

The data represented that a total of 133 differential genes were screened in the GSE157293 dataset and 2869 differential genes in the GSE112943 dataset, yielding a total of 26 differentially co-expressed genes. Six core genes (STAT1, OAS2, OAS3, IFI44, DDX60, and IFI44L) were screened. Biological functional analysis identified key relevant pathways in LN. ROC curve analysis suggested that lncRNA XIST, miR-381-3P, and STAT1 could be used as potential molecular markers to assist in the diagnosis of LN.

CONCLUSION

STAT1 is a key gene in the development of LN. In conclusion, lncRNA XIST, miR-381-3P, and STAT1 can be used as new molecular markers to assist in the diagnosis of LN, and the lncRNA XIST/miR-381-3P/STAT1 axis may be a potential therapeutic target for LN.

Clinical Significance of Overlap Syndrome of Histologically Confirmed Lupus Nephritis with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Objectives: We applied the 2022 American College of Rheumatology/ European Alliance of Association for Rheumatology (ACR/EULAR) criteria for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) to patients histologically diagnosed with lupus nephritis (LN) to investigate the overall rate of and initial contributing factors to the reclassification of overlap syndrome of LN with AAV (OS-LN-AAV). Methods: We retrospectively reviewed the medical records of 1292 patients with systemic lupus erythematosus (SLE) and included 164 patients with LN in this study. Patient demographics, SLE manifestations, LN classes, and laboratory data, including ANCA levels, were recorded. All-cause mortality and end-stage kidney disease (ESKD) were evaluated as poor outcomes. Results: The median age of the 164 patients was 37.0 years, and 12.2% were men. The overall reclassification rate was 37.8%, of which 34.1% and 3.7% of the patients were reclassified as having OS-LN-microscopic polyangiitis and OS-LN-granulomatosis with polyangiitis (GPA), respectively, but none as having eosinophilic GPA. ANCA positivity and AAV-suggesting lung lesions were major contributors to OS-LN-AAV reclassification. When patients were compared based on OS-LN AAV reclassification, ANCA positivity and myeloperoxidase-ANCA (or P-ANCA) positivity favoured for OS-LN-AAV reclassification, whereas oral ulcers did not. However, OS-LN-AAV reclassification did not affect all-cause mortality or ESKD. Conclusions: This is the first study demonstrating a 37.8% reclassification rate in patients histologically diagnosed with LN using the 2022 ACR/EULAR criteria for AAV. Furthermore, it was also the first to reveal ANCA positivity and AAV-suggesting lung lesions as major contributors to OS-LN-AAV reclassification.

Clinical outcomes in lupus nephritis patients treated with belimumab in real-life setting: a retrospective comparative study in China

Objective

The use of belimumab in treating lupus nephritis (LN) patients in China is still in its early stages. This retrospective comparative study aims to delineate the disease activity, associated therapies, clinical outcomes, and adverse events among LN patients treated with belimumab, reflecting real-world experience in southeastern China.

Methods

From May 2020 to December 2023, 54 LN patients treated with belimumab and 42 LN patients treated with conventional therapy were enrolled. All patients had a follow-up period of more than 3 months. The general information, presenting clinical and laboratory data, and outcomes were collected and compared.

Results

At 3 months of belimumab treatment, compared to baseline, there was a decrease in proteinuria from 74.1% to 64.8% (p < 0.001), a reduction in hematuria from 59.3% to 37.0% (p = 0.008), and an increase in partial or complete renal response from 53.7% to 75.9% (p < 0.001). The median SLEDAI score decreased from 10 to 5 (p < 0.001), and the proportion of patients achieving low lupus disease activity state (LLDAS) increased from 11.11% to 16.67% (p < 0.001) by the 3-month evaluation. Notably, there were significant reductions in oral corticosteroid dosages, with a median decrease from 30 to 17.5 mg/day (p < 0.001) by 3 months, and the proportion of patients requiring >5 mg/day of steroids decreased from 88.89% at baseline to 79.07% at six months (p < 0.001). Compared to the conventional therapy group, the belimumab group experienced a significant reduction in median steroid dosage and increased the proportion of patients achieving remission or LLDAS. The incidence of treatment-emergent adverse events (TEAEs) was significantly lower in the belimumab group (29.6% vs 52.4%, p = 0.024).

Conclusion

These findings support the potential of belimumab to improve renal and serological parameters, reduce disease activity, lessen corticosteroid dependence, and decrease the risk of TEAEs, demonstrating its safety and efficacy as an adjunct therapy in LN management.

Cordyceps protein alleviates renal injury by inhibiting T cell infiltration and Th1 cell differentiation in lupus nephritis mice

BACKGROUND

T cell infiltration and differentiation play a central part in the development of lupus nephritis (LN). Our prior research has indicated that protein, the primary active component of cordyceps (WCP), a traditional Chinese medicine, possesses properties that can enhance renal fibrosis and provide kidney protection. Nonetheless, the connection between WCP and T cell infiltration and differentiation in LN remains poorly understood.

OBJECTIVE

The objective of this research was to assess the immunomodulatory impacts of WCP in LN mice and elucidate the underlying mechanism through in vivo and in vitro investigations.

METHODS

To investigate the impact and mechanism of WCP in MRL/lpr lupus-prone mice, WCP (1.5 g/kg/d), Bailing capsules (BC, 0.75 g/kg/d), and saline in equivalent quantities were administered to the mice over a period of 8 weeks. The therapeutic effects, T cell infiltration and differentiation of WCP on MRL/lpr mice were verified through ELISA, Hematoxylin-eosin (H&E), Periodic Acid Schiff (PAS) staining, immunofluorescence, Luminex analysis and flow cytometry. The mechanism by which WCP alleviates LN was investigated using tissues of mice, T cells and Mouse Podocyte Clone-5 (MPC-5) cells by transcriptomics, Western blot (WB), and Real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

We found that WCP improved LN in MRL/lpr mice by reducing urinary protein, creatinine, and serum auto antibodies, increasing complement 3 (C3) level, improving renal immunopathology and downregulating serum cytokines, including IFN-γ, IL-12, and RANTES. Notably, the infiltration of CD4+ and CD8+ T cells in the kidney was reduced by WCP. Similarly, the cell transwell co-culturation study showed that the WCP treated MPC-5 cells were weaker in inducing T cell migration. Consistent with this finding, our observations revealed that WCP could inhibit T cell-related chemokine expression in kidney and MPC-5 cells, as well as reduce the levels of TLR4, MYD88, phosphorylated-p38, phosphorylated-ERK, and phosphorylated-JNK. On the other hand, WCP was found to greatly inhibit the Th1 cells differentiation in vivo and in vitro. Cytokine-receptor induced Th1 cell differentiation pathway and PI3K-AKT pathway were the most enriched pathways based on differentially expressed genes (DEGs) enrichment analysis among different cell groups. Results from RT-qPCR and WB showed that WCP notably reduced the levels of IL-12, p-STAT4, IFN-γ, p-STAT1, p-PI3K, and p-AKT in T cells.

CONCLUSION

WCP demonstrated positive immunomodulatory effects on LN disease, by decreasing the T cells infiltration through TLR4/MYD88/MAPK signaling pathway and inhibiting Th1 cells differentiation via IL-12-STAT4 and IFN-γ-STAT1 pathways, in addition to the PI3K-AKT pathway.

Noninvasive biomarkers for lupus nephritis

Lupus nephritis (LN) is one of the most severe clinical manifestations of systemic lupus erythematosus (SLE). Notably, the clinical manifestations of LN are not always consistent with the histopathological findings. Therefore, the diagnosis and activity monitoring of this disease are challenging and largely depend on invasive renal biopsy. Renal biopsy has side effects and is associated with the risk of bleeding and infection. There is a growing interest in the development of novel noninvasive biomarkers for LN. In this review, we summarize most of the LN biomarkers discovered so far by correlating current knowledge with future perspectives. These biomarkers fundamentally reflect the biological processes of kidney damage and repair during disease. Furthermore, this review highlights the role of urinary cell phenotype detection in the diagnosis, monitoring, and treatment of LN and summarizes the limitations and countermeasures of this test.

Efficacy and safety of telitacicept in patients with lupus nephritis: a single-center, real-world retrospective study

BACKGROUND

Telitacicept, an innovative drug used for the treatment of systemic lupus erythematosus (SLE), can effectively control disease progression and achieve favorable outcomes. While case reports have mentioned the use of Telitacicept in lupus nephritis (LN) treatment, its safety and efficacy in treating patients with LN have not been explored. Therefore, in this study, we aimed to evaluate the safety and efficacy of Telitacicept in managing patients with LN.

METHODS

In a single-center, real-world retrospective study, 30 LN patients with poor response or adverse reactions to conventional glucocorticoids at our Hospital were enrolled to receive Telitacicept. Patients were administered 160 mg of Telitacicept subcutaneously once a week for at least 24 weeks in addition to standard treatment. We assessed the SLE responder index-4 (SRI-4) at the beginning and the end of the treatment period, measured laboratory test indicators at 3, 6, and 9 months, and observed the occurrence of adverse events in these patients.

RESULTS

The SRI-4 response rate was 86.67% (n = 26), with a significantly lower systemic lupus erythematosus disease activity index (SLEDAI) score compared to the baseline. Post Telitacicept treatment, glucocorticoid intake of patients with LN significantly reduced from 50 (IQR:40, 51.25) at baseline to 10 (IQR:5,10) at the endpoint (Z = - 6.547, p < 0.001). Patients with LN showed significantly improved urine occult blood levels after Telitacicept therapy. While the complement (C3 and C4) contents increased, immunoglobulins (IgG, IgA and IgM) reduced markedly (p < 0.001). The negative rate of dsDNA reached 26.67% and adverse events were alleviated post treatment. Only two cases of LN-related adverse reactions were reported, including herpes and infectious fever, respectively. Telitacicept primarily serves as an agent for the induction of remission therapy, with an attainment of complete remission rate standing at a commendable 73.3%.

CONCLUSIONS

Telitacicept treatment reduced disease severity in patients with LN. The initial clinical trial provided supportive evidence for the effectiveness and safety of Telitacicept as a viable treatment option for LN, allowing a reduction in the daily glucocorticoid intake while maintaining a good safety profile, and improving hypocomplementation in LN management.

Lupus Nephritis from Pathogenesis to New Therapies: An Update

Lupus Nephritis (LN) still represents one of the most severe complications of Systemic Lupus Erythematosus (SLE) and a major risk factor for morbidity and mortality. However, over the last few years, several studies have paved the way for a deeper understanding of its pathogenetic mechanisms and more targeted treatments. This review aims to provide a comprehensive update on progress on several key aspects in this setting: pathogenetic mechanisms of LN, including new insight into the role of autoantibodies, complement, vitamin D deficiency, and interaction between infiltrating immune cells and kidney resident ones; the evolving role of renal biopsy and biomarkers, which may integrate information from renal histology; newly approved drugs such as voclosporin (VOC) and belimumab (BEL), allowing a more articulate strategy for induction therapy, and other promising phase III-immunosuppressive (IS) agents in the pipeline. Several adjunctive treatments aimed at reducing cardiovascular risk and progression of chronic renal damage, such as antiproteinuric agents, represent an important complement to IS therapy. Furthermore, non-pharmacological measures concerning general lifestyle and diet should also be adopted when managing LN. Integrating these therapeutic areas requires an effort towards a holistic and multidisciplinary approach. At the same time, the availability of an increasingly wider armamentarium may translate into improvements in patient's renal outcomes over the next decades.

Precision medicine in lupus nephritis

Lupus nephritis (LN) is a prominent manifestation of systemic lupus erythematosus (SLE), characterized by diverse clinical and histopathological features, imposing a substantial burden on patients. Although the exact cause of SLE remain undetermined, several genetic, epigenetics, hormonal, and other factors are implicated in LN pathogenesis. The management of LN rely on invasive renal biopsies, while the standard therapy of the proliferative form of LN remains empirical and relies on indiscriminate immunosuppressants (IS). These treatments exhibit unsatisfactory remission rates, trigger recurrent renal flares, and entail grave adverse effects (ADEs). The advent of precision medicine into LN entails a concentrated effort to pinpoint essential biomarkers, reshaping the landscape of LN management. The primary objective of this review is to synthesize and summarize existing research findings by elucidating the most prevalent immunological, genetic, and epigenetic alterations and deliberate on management strategies that can pave the way for precision medicine in tackling LN. Novel clinical biomarker such as serum anti-complement component 1q (anti-C1q), with urinary markers including neutrophil gelatinase-associated lipocalin (NGAL), monocyte chemoattractant protein-1 (MCP1) and tumour necrosis-like weak inducers of apoptosis (TWEAK) are strongly correlated with LN. These biomarkers have good sensitivity and specificity and perform better than conventional biomarkers in assessing LN activity. Similarly, more renal-specific genetic and epigenetic alteration have been correlated with LN susceptibility and severity. This includes variants of hyaluronan synthase 2 (HAS2), and platelet-derived growth factor receptor alpha (PDGFRA). In the future, integrating clinical, genetic, epigenetic, and targeted therapies holds promise for guiding precision medicine and improving LN outcomes.

CAR T cell therapy for refractory pediatric systemic lupus erythematosus: a new era of hope?

Systemic lupus erythematosus (SLE) is a chronic autoimmune condition that can affect multiple organ systems and is heterogenous in its presentation and response to therapy. When diagnosed in childhood, SLE is associated with increased morbidity and mortality compared to adult SLE, often requiring substantial immunosuppression with the risk of significant side effects. There remains a significant unmet need for new therapies that can improve disease control and reduce glucocorticoid and other toxic medication exposure for patients with severe or refractory disease. The pathogenesis of SLE involves B cell dysregulation and autoantibody production, which are a hallmark of the disease. Currently approved B cell directed therapies often result in incomplete B cell depletion and may not target long-lived plasma cells responsible for SLE autoantibodies. It is hypothesized that by persistently eliminating both B cells and plasmablasts, CAR T therapy can halt autoimmunity and prevent organ damage in patient's refractory to current B cell-depleting treatments. Herein we summarize the current preclinical and clinical data utilizing CAR T cells for SLE and discuss the future of this treatment modality for lupus.

Ocular fundus changes and association with systemic conditions in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs and systems. Ocular involvement is estimated to manifest in one-third of individuals with SLE, of which lupus retinopathy and choroidopathy represent the severe subtype accompanied by vision impairment. Advancements in multimodal ophthalmic imaging have allowed ophthalmologists to reveal subclinical microvascular and structural changes in fundus of patients with SLE without ocular manifestations. Both ocular manifestations and subclinical fundus damage have been shown to correlate with SLE disease activity and, in some patients, even precede other systemic injuries as the first presentation of SLE. Moreover, ocular fundus might serve as a window into the state of systemic vasculitis in patients with SLE. Given the similarities of the anatomy, physiological and pathological processes shared among ocular fundus, and other vital organ damage in SLE, such as kidney and brain, it is assumed that ocular fundus involvement has implications in the diagnosis and evaluation of other systemic impairments. Therefore, evaluating the fundus characteristics of patients with SLE not only contributes to the early diagnosis and intervention of potential vision damage, but also holds considerate significance for the evaluation of SLE vasculitis state and prediction of other systemic injuries.

Advances in research on immunocyte iron metabolism, ferroptosis, and their regulatory roles in autoimmune and autoinflammatory diseases

Autoimmune diseases commonly affect various systems, but their etiology and pathogenesis remain unclear. Currently, increasing research has highlighted the role of ferroptosis in immune regulation, with immune cells being a crucial component of the body's immune system. This review provides an overview and discusses the relationship between ferroptosis, programmed cell death in immune cells, and autoimmune diseases. Additionally, it summarizes the role of various key targets of ferroptosis, such as GPX4 and TFR, in immune cell immune responses. Furthermore, the release of multiple molecules, including damage-associated molecular patterns (DAMPs), following cell death by ferroptosis, is examined, as these molecules further influence the differentiation and function of immune cells, thereby affecting the occurrence and progression of autoimmune diseases. Moreover, immune cells secrete immune factors or their metabolites, which also impact the occurrence of ferroptosis in target organs and tissues involved in autoimmune diseases. Iron chelators, chloroquine and its derivatives, antioxidants, chloroquine derivatives, and calreticulin have been demonstrated to be effective in animal studies for certain autoimmune diseases, exerting anti-inflammatory and immunomodulatory effects. Finally, a brief summary and future perspectives on the research of autoimmune diseases are provided, aiming to guide disease treatment strategies.

Integrated Diffusion Tensor Imaging and Renal Parenchymal Volume for Early Detection and Grading of Split Renal Functional Impairment in Lupus Nephritis

RATIONALE AND OBJECTIVES

To investigate the effectiveness of combining split diffusion tensor imaging (DTI) measurements with split renal parenchymal volume (RPV) for assessing split renal functional impairment in patients with lupus nephritis (LN).

MATERIALS AND METHODS

Seventy-four participants [48 LN patients and 26 healthy volunteers (HV)] were included in the study. All participant underwent conventional MR and DTI (b = 0, 400, and 600 s/mm2) examinations using a 3.0 T MRI scanner to determine the split renal DTI measurements and split RPV. In LN patients, renography glomerular filtration rate (rGFR) was measured using 99mTc-DTPA scintigraphy based on Gates' method, serving as the reference standard to categorize all split kidneys of LN patients into LN with mild impairment (LNm, n = 65 kidneys) and LN with moderate to severe (LNms, n = 31 kidneys) groups according to the threshold of 30 ml/min in spilt rGFR. All statistical analyses were performed using SPSS 25.0 and MedCalc 20.0 software packages.

RESULTS

Only split medullary fractional anisotropy (FA) and the product of split medullary FA and RPV could distinguish pairwise subgroups among the HV and each LN subgroup (all p < 0.05). ROC curve analysis demonstrated that split medullary FA (AUC = 0.866) significantly outperformed other parameters in differentiating HV from LNm groups, while the product of split medullary FA and split RPV was superior in distinguishing LNm and LNms groups (AUC = 0.793) than other parameters. The combination of split medullary FA and split RPV showed best correlation with split rGFR (r = 0.534, p < 0.001).

CONCLUSION

Split medullary FA, and its combination with split RPV, are valuable biomarkers for detecting early functional changes in renal alterations and predicting disease progression in patients with LN.

Understanding the relationship between HCV infection and progression of kidney disease

Hepatitis C virus (HCV) can cause a range of kidney diseases. HCV is the primary cause of mixed cryoglobulinaemia, which leads to cryoglobulinaemic vasculitis and cryoglobulinaemic glomerulonephritis (GN). Patients with acute cryoglobulinaemic vasculitis often exhibit acute kidney disease due to HCV infection, which typically progresses to acute kidney injury (AKI). HCV also increases the risk of chronic kidney disease (CKD) and the likelihood of developing end-stage renal disease (ESRD). Currently, direct-acting antiviral agents (DAAs) can be used to treat kidney disease at different stages. This review focuses on key findings regarding HCV and kidney disease, discusses the impact of DAAs, and highlights the need for further research and treatment.

Value of SLE-DAS in assessing disease activity in patients with systemic lupus erythematosus: a single-centre retrospective study

OBJECTIVES

This study aimed to evaluate the clinical value of the Systemic Lupus Erythematosus Disease Activity Score (SLE-DAS) for assessing disease activity in patients with SLE.

METHODS

Clinical data were collected from patients with SLE who were admitted at the Second Affiliated Hospital of Soochow University from January 2009 to December 2022. The glucocorticoid dose grading was used as the gold standard for disease activity assessment in SLE. The SLE-DAS value was calculated, and the SLE disease activity status was graded based on the SLE-DAS value. Another scoring criterion, the SLE Disease Activity Index 2000 (SLEDAI 2000), served as a control. Spearman correlation analysis was used to calculate the correlation between the scoring criteria and other variables.

RESULTS

The analysis included 396 patients with SLE. A strong correlation was found between SLE-DAS and SLEDAI 2000 (ρ=0.709, 95% CI 0.648 to 0.766, p<0.001), with median SLE-DAS and SLEDAI 2000 scores of 15.32 (7.90 to 24.45) and 13 (8 to 19), respectively. Compared with the SLEDAI 2000 value, the SLE-DAS value correlated better with glucocorticoid dose grading (ρ=0.434 vs 0.518), gammaglobulin use (ρ=0.170 vs 0.318) and immunosuppressant use (ρ=0.122 vs 0.221). A moderate correlation based on disease activity grading was found between SLE-DAS and glucocorticoid dose grading (ρ=0.441), whereas a mild correlation was observed between SLEDAI 2000 and glucocorticoid dose grading (ρ=0.325). Additionally, SLE-DAS revealed a positive correlation with severe thrombocytopenia, cardiac involvement and pulmonary involvement but not SLEDAI 2000.

CONCLUSION

Compared with SLEDAI 2000, SLE-DAS may provide a more accurate disease activity assessment in patients with SLE, especially those with severe thrombocytopenia and cardiopulmonary involvement.

Kidney-Specific Interleukin-17 Responses During Infection and Injury

The kidneys are life-sustaining organs that are vital to removing waste from our bodies. Because of their anatomic position and high blood flow, the kidneys are vulnerable to damage due to infections and autoinflammatory conditions. Even now, our knowledge of immune responses in the kidney is surprisingly rudimentary. Studying kidney-specific immune events is challenging because of the poor regenerative capacity of the nephrons, accumulation of uremic toxins, and hypoxia- and arterial blood pressure-mediated changes, all of which have unexpected positive or negative impacts on the immune response in the kidney. Kidney-specific defense confers protection against pathogens. On the other hand, unresolved inflammation leads to kidney damage and fibrosis. Interleukin-17 is a proinflammatory cytokine that has been linked to immunity against pathogens and pathogenesis of autoinflammatory diseases. In this review, we discuss current knowledge of IL-17 activities in the kidney in the context of infections, autoinflammatory diseases, and renal fibrosis.

Protopanaxadiol improves lupus nephritis by regulating the PTX3/MAPK/ERK1/2 pathway

Lupus nephritis (LN) is a kidney disease that occurs after systemic lupus erythematosus (SLE) affects the kidneys. Pentraxin 3 (PTX3) is highly expressed in the serum of patients with LN. Renal PTX3 deposition is directly related to clinical symptoms such as proteinuria and inflammation. The excessive proliferation of mesangial cells (MCs) is one of the representative pathological changes in the progression of LN, which is closely related to its pathogenesis. Protopanaxadiol (PPD) is the main component of ginsenoside metabolism and has not been reported in LN. The aim of this study was to investigate the relationship between PTX3 and mesangial cell proliferation and to evaluate the potential role and mechanism of PPD in improving LN. PTX3 is highly expressed in the kidneys of LN patients and LN mice and is positively correlated with renal pathological indicators, including proteinuria and PCNA. The excessive expression of PTX3 facilitated the proliferation of MCs, facilitated the activation of the MAPK/ERK1/2 signaling pathway, and increased the expression of HIF-1α. Further studies showed that PPD can effectively inhibit the abnormal proliferation of MCs with high expression of PTX3 and significantly improve LN symptoms such as proteinuria in MRL/lpr mice. The mechanism may be related to the inhibition of the PTX3/MAPK/ERK1/2 pathway. In this study, both in vitro, in vivo, and clinical sample results show that PTX3 is involved in the regulation of MCs proliferation and the early occurrence of LN. Natural active compound PPD can improve LN by regulating the PTX3/MAPK/ERK1/2 pathway.

Rutin alleviates lupus nephritis by inhibiting T cell oxidative stress through PPARγ

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by complex clinical symptoms and multi-organ damage. One of the most prevalent complications of SLE is lupus nephritis (LN). Rutin, a natural flavonoid compound found in various plants used in traditional Chinese medicine, has shown promising anti-inflammatory, antioxidant, and renal protective effects. In our study, we treated MRL/lpr mice, a model known for spontaneously developing LN, with Rutin. Our findings reveal that Rutin markedly reduced serum cytokine and autoantibody levels and decreased inflammatory cell infiltration in renal tissues, thereby ameliorating kidney pathology. In vitro experiments indicated that Rutin's therapeutic effect on LN is linked to its significant reduction of oxidative stress in T cells. Further investigations suggest that Rutin enhances oxidative stress management through the modulation of Peroxisome proliferator-activated receptor gamma (PPARγ). We observed that Rutin modulates PPARγ activity, leading to reduced transcriptional activity of NF-κB and STAT3, which in turn inhibits the secretion of inflammatory cytokines such as IL-6, TNF-α, and IL-17. In summary, Rutin can exert an antioxidant effect by regulating PPARγ and shows therapeutic action against LN.

Artemisinin and its derivatives as promising therapies for autoimmune diseases

Artemisinin, a traditional Chinese medicine with remarkable antimalarial activity. In recent years, studies demonstrated that artemisinin and its derivatives (ARTs) showed anti-inflammatory and immunoregulatory effects. ARTs have been developed and gradually applied to treat autoimmune and inflammatory diseases. However, their role in the treament of patients with autoimmune and inflammatory diseases in particular is less well recognized. This review will briefly describe the history of ARTs use in patients with autoimmune and inflammatory diseases, the theorized mechanisms of action of the agents ARTs, their efficacy in patients with autoinmmune and inflammatory diseases. Overall, ARTs have numerous beneficial effects in patients with autoimmune and inflammatory diseases, and have a good safety profile.