Serum Long Noncoding RNA H19 and CKD Progression in IgA Nephropathy

Long non-coding RNA in IgA nephropathy: a comprehensive review

Immunoglobulin A nephropathy (IgAN) stands as the most prevalent primary glomerulonephritis globally, almost half of patients progress to end-stage kidney disease (ESKD). However, the precise pathogenesis of IgAN remains elusive. Long non-coding RNAs (lncRNAs), non-protein-coding transcripts that regulate gene expression, have been found to exhibit distinct expression patterns in various disease states. Comprehensive bioinformatic analyses from IgAN patients have uncovered differential expression of lncRNAs such as HOTAIR, H19, and MALAT1. Furthermore, a single nucleotide polymorphism in MIR31HG has been linked to IgAN susceptibility and correlated with clinical markers like urinary red blood cells and hemoglobin levels. Lnc-TSI and lnc-CHAF1B-3, specifically expressed in the kidneys of IgAN patients, exhibit associations with renal fibrosis indices and the degree of kidney function deterioration, influencing the progression of renal fibrosis through distinct signaling pathways. Additionally, renal intercellular adhesion molecule 1 (ICAM-1) related long noncoding RNA (ICR) levels positively correlate with IgAN severity and contribute to renal fibrosis, whereas serum H19 serves as an independent protective factor against IgAN. Notably, experiments have validated the involvement of PTTG3P, lnc-CHAF1B-3, and CRNDE in the pathogenesis of IgAN. Nevertheless, data on the roles of lncRNAs in IgAN pathogenesis and their potential as biomarkers remain limited, and effective therapeutic options for IgAN are similarly rare. Therefore, there is an urgent need to bridge this knowledge gap. This article presents a review of current literature on lncRNAs related to IgAN, aiming to consolidate existing findings and identify future research avenues.

LncRNAs and IgA nephropathy: underlying molecular pathways and clinical applications

IgA nephropathy (IgAN), also known as Berger's disease, is a prevalent kidney disorder caused by the accumulation of IgA antibodies in the glomerular tissue. Long noncoding RNAs (lncRNAs), a class of noncoding RNAs longer than 200 nucleotides, play crucial roles in regulating various cellular and molecular processes, including translation, chromatin remodeling, and transcriptional efficiency. Research has highlighted the significant impact of lncRNA imbalances on the development and progression of kidney diseases, including IgAN. These molecules influence several key signaling pathways, such as PI3K/AKT/mTOR, PTEN, Notch, JNK, and immune-related pathways, with their dysregulation contributing to IgAN pathogenesis. This review aims to provide a comprehensive analysis of the molecular signaling pathways involving lncRNAs in IgAN, underscoring their potential as biomarkers for screening, diagnosis, and prevention. Furthermore, it explores the therapeutic potential of lncRNAs as precise targets for personalized treatment strategies.

New biomarkers in IgA nephropathy

Currently, IgA nephropathy (IgAN) is the most common cause of chronic renal failure in patients with primary glomerulonephritis. However, IgAN diagnosis is usually performed by collecting a renal biopsy as gold standard to visualize pathological changes in the glomeruli. The randomized nature of this invasive procedure in clinical practice, together with the need to exclude patients with contraindications, often results in a limited number of eligible people. Therefore, over the past two decades, researchers have explored new biomarkers for IgAN to meet the urgent clinical need for rapid diagnosis and prognosis, as well as realistic prediction of IgAN progression. In addition to traditional common markers with low specificity to detect renal diseases, the classical antibody targeting galactose-deficient IgA1 has been progressively discovered. In addition, new types of diagnostic or prognostic biomarkers are emerging, including microRNA, complement factors, proteases, inflammatory molecules and serum or urinary metabolite profiles.

Up-regulation of long non-coding RNA H19 ameliorates renal tubulointerstitial fibrosis by reducing lipid deposition and inflammatory response through regulation of the microRNA-130a-3p/long-chain acyl-CoA synthetase 1 axis

Long non-coding RNA (lncRNA) H19 is an extensively studied lncRNA that is related to numerous pathological changes. Our previous findings have documented that serum lncRNA H19 levels are decreased in patients with chronic kidney disorder and lncRNA H19 reduction is closely correlated with renal tubulointerstitial fibrosis, an essential step in developing end-stage kidney disease. Nonetheless, the precise function and mechanism of lncRNA H19 in renal tubulointerstitial fibrosis are not fully comprehended. The present work utilized a mouse model of unilateral ureteral obstruction (UUO) and transforming growth factor-β1 (TGF-β1)-stimulated HK-2 cells to investigate the possible role and mechanism of lncRNA H19 in renal tubulointerstitial fibrosis were investigated. Levels of lncRNA H19 decreased in kidneys of mice with UUO and HK-2 cells stimulated with TGF-β1. Up-regulation of lncRNA H19 in mouse kidneys remarkably relieved kidney injury, fibrosis and inflammation triggered by UUO. Moreover, the increase of lncRNA H19 in HK-2 cells reduced epithelial-to-mesenchymal transition (EMT) induced by TGF-β1. Notably, up-regulation of lncRNA H19 reduced lipid accumulation and triacylglycerol content in kidneys of mice with UUO and TGF-β1-stimulated HK-2 cells, accompanied by the up-regulation of long-chain acyl-CoA synthetase 1 (ACSL1). lncRNA H19 was identified as a sponge of microRNA-130a-3p, through which lncRNA H19 modulates the expression of ACSL1. The overexpression of microRNA-130a-3p reversed the lncRNA H19-induced increases in the expression of ACSL1. The suppressive effects of lncRNA H19 overexpression on the EMT, inflammation and lipid accumulation in HK-2 cells were diminished by ACSL1 silencing or microRNA-130a-3p overexpression. Overall, the findings showed that lncRNA H19 ameliorated renal tubulointerstitial fibrosis by reducing lipid deposition via modulation of the microRNA-130a-3p/ACSL1 axis.

Deciphering roles of protein post-translational modifications in IgA nephropathy progression and potential therapy

Immunoglobulin A nephropathy (IgAN), one type of glomerulonephritis, displays the accumulation of glycosylated IgA in the mesangium. Studies have demonstrated that both genetics and epigenetics play a pivotal role in the occurrence and progression of IgAN. Post-translational modification (PTM) has been revealed to critically participate in IgAN development and progression because PTM dysregulation results in impaired degradation of proteins that regulate IgAN pathogenesis. A growing number of studies identify that PTMs, including sialylation, o-glycosylation, galactosylation, phosphorylation, ubiquitination and deubiquitination, modulate the initiation and progression of IgAN. Hence, in this review, we discuss the functions and mechanisms of PTMs in regulation of IgAN. Moreover, we outline numerous compounds that govern PTMs and attenuate IgAN progression. Targeting PTMs might be a useful strategy to ameliorate IgAN.

LncRNA H19: a novel player in the regulation of diabetic kidney disease

Diabetic kidney disease (DKD), one of the most severe complications of diabetes mellitus (DM), has received considerable attention owing to its increasing prevalence and contribution to chronic kidney disease (CKD) and end-stage kidney disease (ESRD). However, the use of drugs targeting DKD remains limited. Recent data suggest that long non-coding RNAs (lncRNAs) play a vital role in the development of DKD. The lncRNA H19 is the first imprinted gene, which is expressed in the embryo and down-regulated at birth, and its role in tumors has long been a subject of controversy, however, in recent years, it has received increasing attention in kidney disease. The LncRNA H19 is engaged in the pathological progression of DKD, including glomerulosclerosis and tubulointerstitial fibrosis via the induction of inflammatory responses, apoptosis, ferroptosis, pyroptosis, autophagy, and oxidative damage. In this review, we highlight the most recent research on the molecular mechanism and regulatory forms of lncRNA H19 in DKD, including epigenetic, post-transcriptional, and post-translational regulation, providing a new predictive marker and therapeutic target for the management of DKD.