Project description:Peritoneal dialysis (PD) is a widely used kidney replacement therapy for patients with end-stage kidney disease. Nevertheless, long-term exposure to PD fluid can damage the peritoneal membrane, leading to ultrafiltration failure and, ultimately, discontinuation of PD. Investigation of the molecular mechanisms underlying this damage is essential for identifying new therapeutic targets to mitigate peritoneal deterioration in PD patients. To this end, we employed RNA sequencing in a preclinical model of peritoneal injury, induced by prolonged chlorhexidine (CHX) exposure, which revealed cytosolic DNA-sensing signaling as a novel pathway. Next, we demonstrated that key players in this pathway, such as the stimulator of interferon genes (STING) and its downstream signaling effectors (interferon regulatory factor 3, interferon-stimulated genes, and nuclear factor-κB signaling), were upregulated in experimental peritoneal damage. Moreover, increased STING expression was observed in human peritoneal biopsies from patients with PD. Subsequent studies in STING-deficient mice showed reduced proinflammatory gene expression and immune cell infiltration, together with inhibited nuclear factor-κB pathway activation at both early (10 days) and late (30 days) stages of CHX-induced peritoneal injury. STING deficiency also reduced peritoneal membrane thickening, fibrosis, and mesothelial-to-mesenchymal transition (MMT)-related changes in advanced CHX-induced damage. Furthermore, pharmacological inhibition of STING with C-176 attenuated CHX-induced peritoneal inflammation. Macrophages were identified as one of the STING-expressing cell types in the injured peritoneum. Hence, in vitro STING blockade in activated macrophages inhibited MMT in cultured mesothelial cells, suggesting that STING activation in this population may drive peritoneal fibrosis. Additionally, STING deficiency reduced peritoneal inflammation in S. epidermidis-induced peritonitis and decreased adhesion scores in a postsurgical intra-abdominal adhesion model. These findings identify STING as a pivotal mediator of peritoneal injury and support its potential as a novel therapeutic target to prevent PD-associated ultrafiltration failure. © 2025 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Project description:Expression data from peritoneal biopsies of patients with encapsulating peritoneal sclerosis (EPS), patients undergoing first implantation of a peritoneal dialysis catheter (PD), and patients undergoing abdominal surgery for non-peritoneal conditions (controls) We used microarrays to determine the transcriptional profiles of peritoneal membrane in patients with encapsulating peritoneal sclerosis (EPS), patients undergoing first insertion of a peritoneal dialysis cathetier (PD), and uremic patients without history of PD or EPS, undergoing abdominal surgery for non-peritoneal problems (CON) Encapsulating peritoneal sclerosis (EPS) is a devastating complication of peritoneal dialysis (PD), characterized by marked inflammation and severe fibrosis of the peritoneum, and associated with high morbidity and mortality. EPS can occur years after termination of PD and, in severe cases, leads to intestinal obstruction and ileus requiring surgical intervention. Despite ongoing research, the pathogenesis of EPS remains unclear. We performed a global transcriptome analysis of peritoneal tissue specimens from EPS patients, PD patients without EPS, and uremic patients without history of PD or EPS (Uremic). Unsupervised and supervised bioinformatics analysis revealed distinct transcriptional patterns that discriminated these three clinical groups. The analysis identified a signature of 219 genes expressed differentially in EPS as compared to PD and Uremic groups. Canonical pathway analysis of differentially expressed genes showed enrichment in several pathways, including antigen presentation, dendritic cell maturation, B cell development, chemokine signaling and humoral and cellular immunity (P value <0.05). Further interactive network analysis depicted effects of EPS-associated genes on networks linked to inflammation, immunological response, and cell proliferation. Gene expression changes were confirmed by qRT-PCR for a subset of the differentially expressed genes. EPS patient tissues exhibited elevated expression of genes encoding sulfatase1, thrombospondin 1, fibronectin 1 and alpha smooth muscle actin, among many others, while in EPS and PD tissues mRNAs encoding leptin and retinol-binding protein 4 were markedly down-regulated, compared to Uremic group patients. Immunolocalization of Collagen 1 alpha 1 revealed that Col1a1 protein was predominantly expressed in the submesothelial compact zone of EPS patient peritoneal samples, whereas PD patient peritoneal samples exhibited homogenous Col1a1 staining throughout the tissue samples. The results are compatible with the hypothesis that encapsulating peritoneal sclerosis is a distinct pathological process from the simple peritoneal fibrosis that accompanies all PD treatment. Total RNA was isolated from frozen peritoneal biopsy specimens obtained at time of surgery. RNA was hybridized to Affymetrix arrays, and analyzed. Select transcripts were subjected to validation by rt-pcr and by immunodetection.

Project description:Expression data from peritoneal biopsies of patients with encapsulating peritoneal sclerosis (EPS), patients undergoing first implantation of a peritoneal dialysis catheter (PD), and patients undergoing abdominal surgery for non-peritoneal conditions (controls) We used microarrays to determine the transcriptional profiles of peritoneal membrane in patients with encapsulating peritoneal sclerosis (EPS), patients undergoing first insertion of a peritoneal dialysis cathetier (PD), and uremic patients without history of PD or EPS, undergoing abdominal surgery for non-peritoneal problems (CON) Encapsulating peritoneal sclerosis (EPS) is a devastating complication of peritoneal dialysis (PD), characterized by marked inflammation and severe fibrosis of the peritoneum, and associated with high morbidity and mortality. EPS can occur years after termination of PD and, in severe cases, leads to intestinal obstruction and ileus requiring surgical intervention. Despite ongoing research, the pathogenesis of EPS remains unclear. We performed a global transcriptome analysis of peritoneal tissue specimens from EPS patients, PD patients without EPS, and uremic patients without history of PD or EPS (Uremic). Unsupervised and supervised bioinformatics analysis revealed distinct transcriptional patterns that discriminated these three clinical groups. The analysis identified a signature of 219 genes expressed differentially in EPS as compared to PD and Uremic groups. Canonical pathway analysis of differentially expressed genes showed enrichment in several pathways, including antigen presentation, dendritic cell maturation, B cell development, chemokine signaling and humoral and cellular immunity (P value <0.05). Further interactive network analysis depicted effects of EPS-associated genes on networks linked to inflammation, immunological response, and cell proliferation. Gene expression changes were confirmed by qRT-PCR for a subset of the differentially expressed genes. EPS patient tissues exhibited elevated expression of genes encoding sulfatase1, thrombospondin 1, fibronectin 1 and alpha smooth muscle actin, among many others, while in EPS and PD tissues mRNAs encoding leptin and retinol-binding protein 4 were markedly down-regulated, compared to Uremic group patients. Immunolocalization of Collagen 1 alpha 1 revealed that Col1a1 protein was predominantly expressed in the submesothelial compact zone of EPS patient peritoneal samples, whereas PD patient peritoneal samples exhibited homogenous Col1a1 staining throughout the tissue samples. The results are compatible with the hypothesis that encapsulating peritoneal sclerosis is a distinct pathological process from the simple peritoneal fibrosis that accompanies all PD treatment.

Project description:Peritoneal dialysis (PD) is the worldwide recognized preferred dialysis treatment for children affected by end-stage kidney disease (ESKD). However, due to the unphysiological composition of PD fluids, the peritoneal membrane (PM) of these patients may undergo structural and functional alterations, which may cause fibrosis. Several factors may accelerate this process and primary kidney disease may have a causative role. In particular, patients affected by corticoresistant primary focal segmental glomerulosclerosis), a rare glomerular disease leading to nephrotic syndrome and ESKD, seem more prone to develop peritoneal fibrosis. The mechanism causing this predisposition is still unrecognized. To better define this condition, we carried out, for the first time, a new comprehensive comparative proteomic mass spectrometry analysis of mesothelial exosomes from peritoneal dialysis effluent (PDE) of 6 pediatric patients with focal segmental glomerular sclerosis (FSGS) versus 6 patients affected by other primary renal diseases (No FSGS). Our omic study demonstrated that, despite the high overlap in the protein milieu between the two study groups, machine learning allowed a complete distinction of the whole proteomic exosome mesothelial content of FSGS versus No FSGS (with 100% accuracy). Out of the 2490 identified proteins, 40% (995) were involved in epithelial-mesenchymal transition (EMT)/fibrosis and in the transforming growth factor-β pathway. Additionally, the Weight Gene Co-expression Network Analysis algorithm identified that some of the discriminative proteins (TIMP1, CTHRC1, SPARC, CHMP4B, COL5A2, ANXA13, FNC2 and CENP-E) were also highly correlated to PD vintage, fibrosis, EMT and non-neoplastic PM disease. All together our data demonstrated that mesothelial cells of FSGS patients are more prone to activate a pro-fibrotic machinery with exosomes having a primary role in this process. Moreover, they indicated that identified FSGS-associated elements in mesothelial exosome protein could be employed as potential new biomarkers of mesothelial integrity. Finally, our results highlighted that in FSGS patients particular attention should be paid to use more biocompatible dialysis solution, reduce the length of time on PD and personalize PD regimens to minimize the risk of rapid loss of PM function or development of encapsulating peritoneal sclerosis.

			Action	DRS
	PD-1_Slot2-19_1_8021.d.zip	Other
	PD-2_Slot2-20_1_8022.d.zip	Other
	PD-3_Slot2-21_1_8023.d.zip	Other
	PD-4_Slot2-22_1_8025.d.zip	Other
	PD-5_Slot2-23_1_8026.d.zip	Other

Dataset Information

4D label-free quantitative proteomics analyses of peritoneal extracellular vesicles isolated from normal mice and peritoneal dialysis fluid-treated mice

Dataset's files

Publications

Proteomic Characterization of Peritoneal Extracellular Vesicles in a Mouse Model of Peritoneal Fibrosis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets