Silence of Long Noncoding RNA SNHG14 Alleviates Ischemia/Reperfusion-Induced Acute Kidney Injury by Regulating miR-124-3p/MMP2 Axis

Abstract

Purpose. Ample evidence has proved that lncRNAs are pivotal regulators in acute kidney injury (AKI). Here, we focus on the role and mechanism of lncRNA SNHG14 in ischemia/reperfusion- (I/R-) caused AKI. Methods. I/R and hypoxia/reoxygenation (H/R) were applied to induce rats and HK-2 cells to establish AKI models in vivo and in vitro. Relative expression of SNHG14, miR-124-3p, and MMP2 was determined by qRT-PCR. HE staining was used to evaluate pathological changes in renal tissues, and acute tubular necrosis (ATN) score was calculated. Renal function was evaluated by measuring serum creatinine content and blood urea nitrogen content. Levels of IL-1β, IL-6, and TNF-α were measured by ELISA. Cell viability was examined by MTT assay. Oxidative stress was assessed by measuring SOD, MDA, and ROS levels. The target of SNHG14 or miR-124-3p was verified by DLR assay. Protein expression of MMP2 was examined by western blot. Results. SNHG14 was boosted in renal tissues of I/R-stimulated rats and H/R-induced HK-2 cells, while miR-124-3p was diminished in H/R-stimulated HK-2 cells. Si-SNHG14 or miR-124-3p mimics repressed inflammation and oxidative stress and enhanced cell viability in H/R-stimulated HK-2 cells. Sh-SNHG14 mitigated I/R-induced AKI in rats. MiR-124-3p was targeted by SNHG14, and MMP2 was targeted by miR-124-3p. Inhibition of miR-124-3p or upregulation of MMP2 reversed inhibitory effects of SNHG14 silence on inflammation and oxidative stress as well as the promoting effect of SNHG14 silence on cell viability in H/R-induced HK-2 cells. Conclusion. Knockdown of SNHG14 alleviated I/R-induced AKI by miR-124-3p-mediated downregulation of MMP2.

Silencing Long Non-coding RNA Kcnq1ot1 Limits Acute Kidney Injury by Promoting miR-204-5p and Blocking the Activation of NLRP3 Inflammasome

“…Then, 10 mice were randomly assigned to a sham group, and the rest of the 30 mice were used to establish the AKI model and randomly assigned to 3 groups ( N = 10), which are ischemia/reperfusion (I/R) group (30 min of bilateral ischemia), sh-NC group (injected slowly with a total volume of 20 μl sh-NC adenovirus with a titer of 1 × 10 7 particles/μl via the caudal vein using a 4-gauge needle 1 week before I/R treatment), and sh-Kcnq1ot1 group (injected with 20 μl sh-Kcnq1ot1 adenovirus with 1 × 10 7 particles/μl via the caudal vein 1 week before I/R treatment). The sh-Kcnq1ot1 or sh-NC (sh-Kcnq1ot1 sequence: 5′-GCAGAACCAUCGAUGGUGCGU-3′; sh-NC: 5′-AGUGCUGCGCACGUGUCUCAU-3′; RiboBio, Beijing, China) was introduced into the adenoviral vector (Life Technologies, Shanghai, China) to form adenovirus solution of sh-Kcnq1ot1 or sh-NC by using Gateway TM LR Clonase II Enzyme Mix (Invitrogen, Carlsbad, CA, United States) ( Xue et al, 2021 ). Mice were intraperitoneally injected with pentobarbital sodium (60 mg/kg; Sigma-Aldrich, St. Louis, MO, United States) to ensure that mice were fully anesthetized before the surgery and a heating pad was used to maintain the body temperature of mice.…”

“…All mice were euthanized after 2 h of reperfusion. After taking a.5 ml blood sample from the orbit, the kidney tissues were collected, followed by further analysis of the blood sample and kidney tissues ( Lempiainen et al, 2012 ; Xue et al, 2021 ). The kidney tissues of five mice in each group were fixed with 4% paraformaldehyde for 8 h, dehydrated with conventional alcohol, cleared with xylene, embedded in paraffin, and cut into 5 μm for hematoxylin and eosin (HE) staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining.…”

“…Acute tubular necrosis (ATN) scoring system was adopted to analyze pathological injury. The tissue damage was quantified in a blinded manner and scored according to the percentage of damaged tubules in the sample: 0, no damage; 1, <25% damage; 2, 25–50% damage; 3, 50–75% damage; 4, >75% damage ( Lempiainen et al, 2012 ; Xue et al, 2021 ).…”

Non-Coding RNAs in Kidney Diseases: The Long and Short of Them

“…The gene blockade of LINC00520 reduced renal damage through the attenuation of OSMR levels and PI3K/AKT signaling pathway [ 56 ]. In addition, the gene blockade of LncRNA SNHG14 in I/R reduced inflammation and oxidative stress by modulating miR-124-3p, which regulates MMP2 levels [ 57 ]. In two recent studies, HK2 cells under hypoxia increased HIF-1α levels through the LncRNA PRINS and its interaction with CCL5 [ 58 ].…”

MiR-124 Negatively Regulated PARP1 to Alleviate Renal Ischemia-reperfusion Injury by Inhibiting TNFα/RIP1/RIP3 Pathway

“…Overexpressed miR-124 effectively inhibited chronic inflammation in renal tubular epithelial cells induced by LPS [13]. Low expression of miR-124 was detected in renal cancer cell lines OS-RC-2, 769-P and HK-2 cells, and miR-124 inhibited the invasion of cancer cells [14]. However, the mechanism of miR-124 in renal IRI is not clear and further research is needed to functionally elucidate.…”