Project description:Background: We hypothesize that the poor survival outcomes of end-stage kidney disease (ESKD) patients undergoing hemodialysis are associated with a low filtering efficiency and selectivity. The current gold standard criteria using single or several markers show an inability to predict or disclose the treatment effect and disease progression accurately. Methods: We performed an integrated mass spectrometry-based metabolomic and proteomic workflow capable of detecting and quantifying circulating small molecules and proteins in the serum of ESKD patients. Markers linked to cardiovascular disease (CVD) were validated on human induced pluripotent stem cell (iPSC)-derived cardiomyocytes. Results: We identified dozens of elevated molecules in the serum of patients compared with healthy controls. Surprisingly, many metabolites, including lipids, remained at an elevated blood concentration despite dialysis. These molecules and their associated physical interaction networks are correlated with clinical complications in chronic kidney disease. This study confirmed two uremic toxins associated with CVD, a major risk for patients with ESKD. Conclusion: The retained molecules and metabolite-protein interaction network address a knowledge gap of candidate uremic toxins associated with clinical complications in patients undergoing dialysis, providing mechanistic insights and potential drug discovery strategies for ESKD.
Project description:We conducted a calculi rat model, applied for an integrated proteomic and transcriptomic analysis to characterize the distinct gene expression profiles in calculi oxalate stone formation and its related kidney injury. Six distinct gene clusters were identified according to the consistency of transcriptome and proteome. Gene Ontology and KEGG pathway enrichment was performed to analyze the functions of each sub-group differentially expressed genes. Results showed that the calculi rat kidney was increased expression of injured & apoptotic markers and immune-molecules, and decreased expression of solute carriers & transporters and many metabolic related factors. The present proteotranscriptomic study provided a data resource and new insights for better understanding of the pathogenesis of nephrolithiasis, will hopefully facilitate the future development of new strategies for the recurrence prevention and treatment in patients with kidney stone disease.
Project description:Purpose: End-stage renal disease (ESRD) is a condition that is characterized by the loss of kidney function. ESRD patients suffer from various endothelial dysfunctions, inflammation, and immune system defects. Lysine malonylation (Kmal) is a recently discovered post-translational modification (PTM). Although Kmal has the ability to regulate a wide range of biological processes in various organisms, its specific role in ESRD is limited. Experimental design: In this study, the affinity enrichment and liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques have been used to create the first global proteome and malonyl proteome (malonylome) profiles of peripheral blood mononuclear cells (PBMCs) from twenty patients with ESRD and eighty-one controls. Results: On analysis, 793 differentially expressed proteins (DEPs) and 12 differentially malonylated proteins (DMPs) with 16 Kmal sites were identified. The Rap1 signaling pathway and platelet activation pathway were found to be important in the development of chronic kidney disease (CKD), as were DMPs TLN1 and ACTB, as well as one malonylated site. One conserved Kmal motif was also discovered. Conclusion: These findings provided the first report on the Kmal profile in ESRD, which could be useful in understanding the potential role of lysine malonylation modification in the development of ESRD.
Project description:Mutations of the transcription factor TFAP2A are associated with congenital anomalies of the kidney and urinary tract in humans. In mice, deficiency of its ortholog Tfap2a in collecting duct cells causes widened epithelial tubules in the outer medulla of the adult kidney, but the molecular mechanisms of this phenotype are unknown. In this study, we identified gene regulatory networks controlled by Tfap2a in mouse kidney collecting ducts by combining gene knockout and transcriptomics. Integrated analyses of single-nucleus and bulk RNA-sequencing data from kidneys of adult Tfap2a knockout and control mice indicated deregulated expression of genes associated with cell adhesion and Wnt signaling pathways. Validation studies revealed that Tfap2a controls Wnt9b and Alcam, known regulators of kidney tubule morphogenesis. Our data provide novel insights into kidney epithelial gene regulatory networks controlled by Tfap2a and its potential functional role in congenital renal disease.
Project description:Background: Pyroptosis plays a critical role in eliminating pathogens and facilitating tissue repair; however, sustained pyroptosis-driven inflammation accelerates kidney injury and disease progression. Thus, elucidating the mechanisms governing pyroptosis is essential for developing effective therapies for inflammatory kidney diseases such as acute kidney injury (AKI), which currently lacks specific treatment options. Methods: Changes in tubular epithelial cells following drug-induced AKI were assessed using single-cell RNA sequencing, immunohistochemistry, and immunofluorescence. Mechanistic insights were obtained through RNA sequencing, genomic manipulation, transcriptomic profiling, luciferase reporter assays, co-immunoprecipitation, and Western blotting. Tubular epithelial cell fate was further evaluated using transgenic mouse models and pharmacological interventions. Results: We identified activating transcription factor 4 (ATF4) as a key regulator of inflammation in drug-induced AKI. As the master regulator of the integrated stress response, ATF4 was markedly upregulated in renal tubules and positively correlated with kidney dysfunction in both human and murine AKI models. The specific deletion of ATF4 in tubular epithelial cells significantly ameliorated kidney dysfunction, inflammation, and mitochondrial apoptosis, whereas ATF4 activation exacerbated these pathological features. Mechanistically, ATF4 suppression inhibited STAT1 phosphorylation and disrupted its interaction with GBP2, thereby attenuating NLRP3 inflammasome activation, preventing tubular epithelial cells' pyroptosis, and improving kidney function. Notably, inhibition of ATF4—either pharmacologically using our prioritized integrated stress response antagonist ERMT1 or through engineered nanobiologics-mediated silencing of tubular epithelial cells—significantly reduced renal inflammation and injury. Conclusions: ATF4 promoted pyroptosis in drug-induced AKI through STAT1–GBP2 signaling.
Project description:Chronic kidney disease (CKD) is the leading cause of mortality in aged cats. After injury, feline kidneys undergo extensive metabolic reprogramming, but a comprehensive evaluation is lacking. Integration of serum metabolome from early stages, late stages CKD and healthy control cats with renal cortex and medulla transcriptome and proteome can reveal spatiotemporal patterns of gene and protein expression changes. In this study, we conducted mass spectrometry (MS)-based proteomic analysis of kidney (cortex and medulla) tissues from cats with CKD and control cats, euthanized for humane reasons unrelated to the study.
Project description:Mutations of the transcription factor TFAP2A are associated with congenital anomalies of the kidney and urinary tract in humans. In mice, deficiency of its ortholog Tfap2a in collecting duct cells causes widened epithelial tubules in the outer medulla of the adult kidney, but the molecular mechanisms of this phenotype are unknown. In this study, we identified gene regulatory networks controlled by Tfap2a in mouse kidney collecting ducts by combining gene knockout and transcriptomics. Integrated analyses of single-nucleus and bulk RNA-sequencing data from kidneys of adult Tfap2a knockout and control mice indicated deregulated expression of genes associated with cell adhesion and Wnt signaling pathways. Validation studies revealed that Tfap2a controls Wnt9b and Alcam, known regulators of kidney tubule morphogenesis. Our data provide novel insights into kidney epithelial gene regulatory networks controlled by Tfap2a and its potential functional role in congenital renal disease.