1.Role of ferroptosis in fibrosis: From mechanism to potential therapy
Xuemeng QIU ; Qing BI ; Jiyue WU ; Zejia SUN ; Wei WANG
Chinese Medical Journal 2024;137(7):806-817
Fibrosis, which is a manifestation of the physiological response to injury characterized by excessive accumulation of extracellular matrix components, is a ubiquitous outcome of the repair process. However, in cases of repetitive or severe injury, fibrosis may become dysregulated, leading to a pathological state and organ failure. In recent years, a novel form of regulated cell death, referred to as ferroptosis, has been identified as a possible contributor to fibrosis; it is characterized by iron-mediated lipid peroxidation. It has garnered attention due to the growing body of evidence linking ferroptosis and fibrogenesis, which is believed to be driven by underlying inflammation and immune responses. Despite the increasing interest in the relationship between ferroptosis and fibrosis, a comprehensive understanding of the precise role that ferroptosis plays in the formation of fibrotic tissue remains limited. This review seeks to synthesize previous research related to the topic. We categorized the different direct and indirect mechanisms by which ferroptosis may contribute to fibrosis into three categories: (1) iron overload toxicity; (2) ferroptosis-evoked necroinflammation, with a focus on ferroptosis and macrophage interplay; and (3) ferroptosis-associated pro-fibrotic factors and pathways. Furthermore, the review considers the potential implications of these findings and highlights the utilization of ferroptosis-targeted therapies as a promising strategy for mitigating the progression of fibrosis. In conclusion, novel anti-fibrotic treatments targeting ferroptosis could be an effective treatment for fibrosis.
2.Constructing a diagnostic prediction model for antibody-mediated rejection after kidney transplantation based upon bioinformatics and machine learning algorithms
Jiyue WU ; Zejia SUN ; Qing BI ; Xuemeng QIU ; Wei WANG
Chinese Journal of Organ Transplantation 2024;45(10):718-727
Objective:To construct a diagnostic prediction nomogram for antibody-mediated rejection (AMR) after kidney transplantation (KT) based upon peripheral blood gene expression profiling and preliminarily screening potential drugs for AMR.Methods:Seven large kidney transplant cohort datasets related to AMR were retrieved from the database of GEO. Differential expression analysis was utilized for identifying differentially expressed genes between AMR and normal recipients. Multiple machine learning algorithms of random forest (RF), extreme gradient boosting (XGB), support vector machine (SVM) and generalized linear model (GLM) were employed for constructing diagnostic models for AMR after kidney transplantation. Receiver operating characteristic (ROC) curve was plotted for comparing the accuracy of each model. The key genes of optimal model were integrated for creating a diagnostic prediction nomogram for AMR. Calibration curve and decision curve analyses were employed for evaluating the accuracy of nomogram. The differentially expressed genes from biopsy tissues of AMR recipients were uploaded to the database of CMap for identifying potential therapeutic drugs through screening Top 5 compounds with opposite expression patterns to AMR.Results:Seven genes of CXCL10, FCGR1B, GBP5, CD69, LY96, BCL2A1 and EVI2A were over-expressed in both peripheral blood and biopsy tissues of AMR recipients. There were statistically significant differences with recipients without AMR (FDR<0.05). The AMR diagnostic model based upon RF algorithm demonstrated the highest AUC value (0.904) among various machine learning algorithms. Its AUC values were 0.876 and 0.824 in external datasets of GSE50084 and GSE175718. As for the diagnostic prediction nomogram constructed through integrating five key genes of BCL2A1, CXCL10, FCGR1BP, CD69 & EVI2A from RF model, calibration curve indicated that the predicted outcomes of nomogram approximated actual outcomes. Decision curve indicated that net benefit rate of nomogram was higher than that of extreme curves over a wide range of horizontal axis. The predicted results of CMap suggested that Top 5 compounds were raltegravir, rilmenidine, hydrastine, metyrapone and valproic acid.Conclusions:The nomogram constructed based upon peripheral blood gene expression profiling demonstrates high accuracy and generalizability in the diagnosis of AMR. As predicted by CMap, raltegravir, rilmenidine, hydrastine, metyrapone and valproic acid may be potential therapeutic drugs for AMR.