Silencing of long noncoding RNA XIST protects against renal interstitial fibrosis in diabetic nephropathy via microRNA-93-5p-mediated inhibition of CDKN1A

Abstract

Long noncoding RNAs (lncRNAs) have been reported to play an important role in diabetic nephropathy (DN). However, the molecular mechanism involved in this process remains poorly understood. Thus, the present study aimed to explore the function and molecular mechanism of dysregulated lncRNA X-inactive specific transcript (XIST) in DN. DN mouse models were established by streptozotocin treatment, and human renal tubular epithelial HK-2 cells were exposed to high glucose to produce an in vitro model. XIST was highly expressed in renal tissues of patients with DN, mice with DN, and high glucose-exposed HK-2 cells. To identify the interaction among XIST, miR-93-5p, and cyclin-dependent kinase inhibitor 1A (CDKN1A) and to analyze the functional significance of their interaction in renal interstitial fibrosis, we altered endogenous expression of XIST and miR-93-5p and CDKN1A. Dual-luciferase reporter assay results suggested that XIST was highly expressed in the kidney tissue of DN mice and high glucose-exposed HK-2 cells. XIST was identified to be a lncRNA that could bind to miR-93-5p, and CDKN1A was a target of miR-93-5p. Downregulated expression of XIST led to an increase in miR-93-5p expression, thereby decreasing CDKN1A and suppressing renal interstitial fibrosis in DN. Consistently, XIST knockdown reduced the expression of fibrosis markers (fibronectin, collagen type IV, and transforming growth factor-β1). Restoration of CDKN1A or decreasing miR-93-5p yielded a reversed effect on renal interstitial fibrosis. In conclusion, our study demonstrated that silenced XIST inducing miR-93-5p-dependent CDKN1A inhibition was beneficial for preventing renal interstitial fibrosis in DN, which may provide a future strategy to prevent the progression of DN.

LncRNA ARAP1‐AS2 promotes high glucose‐induced human proximal tubular cell injury via persistent transactivation of the EGFR by interacting with ARAP1

“…Many studies have reported that lncRNAs participate in DN through regulating target gene expression 20,21 . For example, silencing of the lncRNA XIST contributed to preventing renal interstitial fibrosis in DN 22 . Ge et al 23 also found that overexpression of the lncRNA NR_038323 regulated renal fibrosis via the miR‐324‐3p/DUSP1 axis in DN.…”

EDN1-AS, A Novel Long Non-coding RNA Regulating Endothelin-1 in Human Proximal Tubule Cells

“…The lncRNAs are a newly recognized mechanism for gene regulation and are being explored as potential therapeutic targets in a variety of diseases (Li et al, 2018;Pecero et al, 2019;Wang et al, 2020), including diabetic nephropathy (Ge et al, 2019;Yang et al, 2019). A nucleic acid-based approach could allow greater specificity than pharmacological compounds, reducing side effects and allowing tissue-specific delivery (Sharma and Watts, 2015;Ku et al, 2016).…”

Noncoding RNAs in Diabetic Nephropathy: Pathogenesis, Biomarkers, and Therapy

“…In renal tissues of DN patients, DN mice, and high glucose-exposed HK-2 cells, lncRNA X-inactive specific transcript (XIST) was found to be highly increasing. Downregulated expression of XIST led to an increase in miR-93-5p expression, thereby decreasing CDKN1A and suppressing renal interstitial fibrosis in DN [85]. Overall, although the potential role of lncRNAs in the pathogenesis of DN has not been fully understood, emerging evidence shows the importance of lncRNAs in the progression of DN.…”