LncRNA TUG1 competitively binds to miR-340 to accelerate myocardial ischemia-reperfusion injury

Non-coding RNAs in the pathophysiology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is the largest unmet clinical need in cardiovascular medicine. Despite decades of research, the treatment option for HFpEF is still limited, indicating our ongoing incomplete understanding on the underlying molecular mechanisms. Non-coding RNAs, comprising of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are non-protein coding RNA transcripts, which are implicated in various cardiovascular diseases. However, their role in the pathogenesis of HFpEF is unknown. Here, we discuss the role of miRNAs, lncRNAs and circRNAs that are involved in the pathophysiology of HFpEF, namely microvascular dysfunction, inflammation, diastolic dysfunction and cardiac fibrosis. We interrogated clinical evidence and dissected the molecular mechanisms of the ncRNAs by looking at the relevant in vivo and in vitro models that mimic the co-morbidities in patients with HFpEF. Finally, we discuss the potential of ncRNAs as biomarkers and potential novel therapeutic targets for future HFpEF treatment.

lncRNA TUG1 as potential novel biomarker for prognosis of cardiovascular diseases

Globally, cardiovascular diseases (CVDs) are among the leading causes of death. In light of the high prevalence and mortality of CVDs, it is imperative to understand the molecules involved in CVD pathogenesis and the signaling pathways that they initiate. This may facilitate the development of more precise and expedient diagnostic techniques, the identification of more effective prognostic molecules and the identification of potential therapeutic targets. Numerous studies have examined the role of lncRNAs, such as TUG1, in CVD pathogenesis in recent years. According to this review article, TUG1 can be considered a biomarker for predicting the prognosis of CVD.

Dexmedetomidine abates myocardial ischemia reperfusion injury through inhibition of pyroptosis via regulation of miR-665/MEF2D/Nrf2 axis

The current study intended to delve into the mechanisms of dexmedetomidine (Dex) in regulating myocardial pyroptosis against myocardial ischemia/reperfusion injury (MIRI). The rat MIRI models were induced by ligation/release of the coronary artery in vivo and Langendorff perfusion ex vivo. Hemodynamic parameters, infarction sizes, and histopathological changes were assessed to understand the effects of Dex on MIRI. We explored the mechanisms through functional experiments on an H9c2 cell hypoxia/reoxygenation (H/R) model. Cell viability and apoptosis were evaluated using cell counting kit 8 (CCK-8) and AV/PI dual staining respectively. The expressions of miR-665 and MEF2D mRNA were detected by qRT-PCR. Western blot was employed to determine the expression levels of pyroptosis- and signaling pathway- related proteins. The interplays between miR-665 and MEF2D were validated by Dual-luciferase reporter assays. Our findings indicated that Dex preconditioning dramatically attenuated hemodynamic derangements, infarct size, and histopathological damage in rats undergoing MIRI. Dex markedly augmented cell viability, while suppressing cell apoptosis and expressions of NLRP3, cleaved-caspase-1, ASC, GSDMD, IL-1β, and IL-18 in H9c2 cells subjected to H/R injury. MiR-665 was significantly upregulated, MEF2D and Nrf2 downregulated following H/R, whereas Dex preconditioning reversed these changes. MEF2D was validated to be a target gene of miR-665. Overexpression of miR-665 decreased the expression of MEF2D and blunted the protective effects of Dex in H9c2 cells. Moreover, the functional rescue experiment further verified that Dex regulated MEF2D/Nrf2 pathway via miR-665. In conclusion, Dex mitigates MIRI through inhibiting pyroptosis via regulating miR-665/MEF2D/Nrf2 axis.

The mechanism of rh-endostatin-induced cardiotoxicity and its protection by dihydromyricetin[in vivo/in vitro, C57BL/6 mice, AC16 and hiPSC-CMs]

Recombinant human endostatin (rh-endostatin) is an anti-angiogenic drug, which is used for the treatment of advanced non-small-cell lung cancer (NSCLC) and other cancers. However, its side effects, especially the cardiotoxicity with unclear mechanisms limit its wide application in clinical practice. In this study, human cardiomyocyte cell line AC16 and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) treated with different doses of rh-endostatin were used to analyze its effect on cardiac cell toxicity. The results revealed that rh-endostatin dose-dependently enhanced cardiomyocyte apoptosis through Apaf-1 apoptotic factor and apoptosis-related proteins such as p53. rh-endostatin-induced changes of mitochondrial function and mitophagy were involved in rh-endostatin-mediated cardiac cell toxicity. Rh-endostatin-induced cardiotoxicity was further verified in vivo in mice. Interestingly, Rh-endostatin-induced cardiotoxicity was inhibited by dihydromyricetin (DHM) both in cultured cells in vitro and in mouse hearts in vivo. The study provides new inside into rh-endostatin-induced cardiotoxicity and identified a novel potential medication DHM to overcome the serious adverse effect.

Role of mechano-sensitive non-coding RNAs in bone remodeling of orthodontic tooth movement: recent advances

Orthodontic tooth movement relies on bone remodeling and periodontal tissue regeneration in response to the complicated mechanical cues on the compressive and tensive side. In general, mechanical stimulus regulates the expression of mechano-sensitive coding and non-coding genes, which in turn affects how cells are involved in bone remodeling. Growing numbers of non-coding RNAs, particularly mechano-sensitive non-coding RNA, have been verified to be essential for the regulation of osteogenesis and osteoclastogenesis and have revealed how they interact with signaling molecules to do so. This review summarizes recent findings of non-coding RNAs, including microRNAs and long non-coding RNAs, as crucial regulators of gene expression responding to mechanical stimulation, and outlines their roles in bone deposition and resorption. We focused on multiple mechano-sensitive miRNAs such as miR-21, - 29, -34, -103, -494-3p, -1246, -138-5p, -503-5p, and -3198 that play a critical role in osteogenesis function and bone resorption. The emerging roles of force-dependent regulation of lncRNAs in bone remodeling are also discussed extensively. We summarized mechano-sensitive lncRNA XIST, H19, and MALAT1 along with other lncRNAs involved in osteogenesis and osteoclastogenesis. Ultimately, we look forward to the prospects of the novel application of non-coding RNAs as potential therapeutics for tooth movement and periodontal tissue regeneration.

Berberine up‐regulates miR‐340‐5p to protect myocardial ischaemia/reperfusion from HMGB1‐mediated inflammatory injury

AIMS

Myocardial ischaemia/reperfusion injury (MIRI) is a major cause of heart failure after myocardial infarction. Berberine (BBR) presents anti-inflammatory and immunosuppressive properties in many diseases. Our research looked into the therapeutic effects and mechanism of BBR in MIRI.

METHODS AND RESULTS

MIRI animal and cell models were established. The mRNA and protein expressions were assessed using reverse transcription and quantitative real-time polymerase chain reaction and western blot. The haemodynamic parameters (left ventricular ejection fraction and left ventricular ejection fraction) were detected by echocardiography. The myocardial infarct size and myocardium lesion were assessed by triphenyltetrazolium chloride and haematoxylin-eosin staining. The levels of injury factors were determined by ELISA. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling staining was performed to analyse cell apoptosis. Dual luciferase reporter gene and RNA immunoprecipitation assays were carried out to verify the interaction between miR-340-5p and HMGB1. BBR administration could improve the haemodynamic parameters and infarct size in MIRI rats (all P < 0.05). In MIRI rat model, BBR reduced cardiomyocyte apoptosis and inflammation (all P < 0.05). BBR could promote miR-340-5p expression (0.64 ± 0.21, P < 0.05), which is lowly expressed in MIRI group (0.24 ± 0.10, P < 0.01) in compare with the sham group (0.99 ± 0.01). MiR-340-5p knockdown abolished the protective effects of BBR on H/R-treated cardiomyocytes (all P < 0.05). BBR suppressed the HMGB1/TLR4/NF-κB pathway activation in MIRI. HMGB1 functioned as the target of miR-340-5p, and its silencing reversed the effect of miR-340-5p inhibitor on BBR-treated MIRI.

CONCLUSIONS

In MIRI, BBR repressed HMGB1-mediated TLR4/NF-κB signalling pathway through miR-340-5p to suppress cardiomyocyte apoptosis and inflammation.

LncRNA Tug1 Contributes Post-stroke NLRP3 Inflammasome-Dependent Pyroptosis via miR-145a-5p/Tlr4 Axis

Pyroptosis, a type of programmed cell death illuminated by inflammasomes and active caspases, is implicated in post-stroke inflammation. Our previous study showed that lncRNA taurine upregulated gene 1 (Tug1) sponging miR-145a-5p modulated microglial activation after oxygen-glucose deprivation (OGD). However, the role and mechanism of Tug1 on post-stroke pyroptosis is not fully clear. Photo-thrombosis stroke mice and OGD-treated BV-2 microglia were established respectively. Tug1 knockdown or overexpression was achieved by intraventricular infusion of AAV-shTug1 in vivo, or transfection of siTug1 and pcDNA3.1-Tug1 in vitro. Neurological function and infarction volume were evaluated. Meanwhile, pyroptosis-associated proteins (IL-1β, IL-18, NLRP3, ASC, cleaved-caspase-1, and GSDMD-N), TLR4, and p-p65/p65 as well as Tug1 and miR-145a-5p were detected 24 h after photo-thrombosis or 4 h after OGD by qRT-PCR, western blot, and ELISA. The correlation between Tug1/miR-145a-5p/Tlr4 axis and pyroptosis was explored by dual-luciferase reporter assay and functional gain-and-loss experiments. Photo-thrombosis or OGD caused neural injury and upregulated pyroptosis-associated proteins, Tug1, TLR4, and p-p65 as well as downregulated miR-145a-5p, which was prevented by Tug1 knockdown in vivo and in vitro. Tlr4 gene, putatively binding with miR-145a-5p by bioinformatics analysis, was found to be a direct target of miR-145a-5p with negative interactions. Furthermore, miR-145a-5p inhibitor abolished the inhibitive effects of siTug1 on TLR4 and p-p65 as well as pyroptosis-associated proteins, whereas miR-145a-5p mimics abrogated the enhanced effects of pcDNA3.1-Tug1 on that, suggesting an involvement of Tug1/miR-145a-5p/Tlr4 axis on pyroptosis. Tug1 contributes NLRP3 inflammasome-dependent pyroptosis through miR-145a-5p/Tlr4 axis post-stroke, providing a promising therapeutic strategy against inflammatory injury.

Non-Coding RNA Networks as Potential Novel Biomarker and Therapeutic Target for Sepsis and Sepsis-Related Multi-Organ Failure

According to “Sepsis-3” consensus, sepsis is a life-threatening clinical syndrome caused by a dysregulated inflammatory host response to infection. A rapid identification of sepsis is mandatory, as the extent of the organ damage triggered by both the pathogen itself and the host’s immune response could abruptly evolve to multiple organ failure and ultimately lead to the death of the patient. The most commonly used therapeutic strategy is to provide hemodynamic and global support to the patient and to rapidly initiate broad-spectrum empiric antibiotic therapy. To date, there is no gold standard diagnostic test that can ascertain the diagnosis of sepsis. Therefore, once sepsis is suspected, the presence of organ dysfunction can be assessed using the Sepsis-related Organ Failure Assessment (SOFA) score, although the diagnosis continues to depend primarily on clinical judgment. Clinicians can now rely on several serum biomarkers for the diagnosis of sepsis (e.g., procalcitonin), and promising new biomarkers have been evaluated, e.g., presepsin and adrenomedullin, although their clinical relevance in the hospital setting is still under discussion. Non-codingRNA, including long non-codingRNAs (lncRNAs), circularRNAs (circRNAs) and microRNAs (miRNAs), take part in a complex chain of events playing a pivotal role in several important regulatory processes in humans. In this narrative review we summarize and then analyze the function of circRNAs-miRNA-mRNA networks as putative novel biomarkers and therapeutic targets for sepsis, focusing only on data collected in clinical settings in humans.

LncRNA MALAT1 promotes decidualization of endometrial stromal cells via sponging miR-498-3p and targeting histone deacetylase 4

Decidualization of human endometrial stromal cells (hESCs) is important for the maintenance of a successful pregnancy. Histone deacetylase 4 (HDAC4) was reported to be involved in the dysfunction of decidua-derived mesenchymal stem cells. However, the role of HDAC4 underlying decidualization of hESCs remains unclear. We intended to explore the function and molecular mechanism of HDAC4 in hESCs. In vitro expansion of hESCs using a serum-free medium was used to confirm the characteristics of hESCs. Gene expression in hESCs was evaluated by reverse transcription-quantitative polymerase chain reaction. CCK-8 assay, TUNEL staining, flow cytometry analysis, and Western blot analysis were performed to test the effects of HDAC4 and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) on hESCs. RNA pull-down and luciferase reporter assays were performed to validate the relationship between genes. In this study, the characteristics of hESCs were sustained in serum-free medium during a process of propagation. HDAC4 knockdown suppressed hESCs viability and promoted hESCs apoptosis. HDAC4 was targeted by miR-498-3p in hESCs. MALAT1 bound with miR-498-3p in hESCs. HDAC4 expression was positively regulated by MALAT1 and negatively regulated by miR-498-3p in hESCs. HDAC4 upregulation countervailed the effects of MALAT1 silencing on hESCs proliferation, apoptosis, and decidualization of hESCs. Overall, MALAT1 facilitated the decidualization of hESCs via binding with miR-498-3p and upregulating HDAC4, which might provide a new direction for the maintenance of a successful pregnancy.

miR-340-5p Alleviates Oxidative Stress Injury by Targeting MyD88 in Sepsis-Induced Cardiomyopathy

Background

Sepsis-induced cardiomyopathy (SIC) is a sort of severe disease in the intensive care unit. This research focuses on exploring the influence of miR-340-5p on SIC and its specific mechanism.

Methods

Mice were administered with lipopolysaccharide (LPS) to construct a SIC animal model. Mice were intramyocardially injected with Adenoassociated Virus- (AAV-) 9 containing the miR-340-5p precursor to make the miR-340-5p overexpression in the myocardium. The expression level of myocardial miR-340-5p was evaluated by qRT-PCR. The cardiac function was measured by echocardiography, the myocardial morphology was observed by hematoxylin-eosin (HE) staining, and the oxidative stress level was detected by 4-hydroxynonenal (4-HNE) immunohistochemical staining and malondialdehyde (MDA) assay in mice. The cells were pretreated with miR-340-5p mimic, mimic-NC, miR-340-5p inhibitor, inhibitor-NC, MyD88 siRNA, or si-NC and then administered with LPS or PBS. The cell viability was measured with the CCK-8 assay. The level of intracellular oxidative stress was evaluated using reactive oxygen species (ROS), MDA, and glutathione (GSH) detection. The MyD88 level was assessed via Western blotting analysis. The interaction of miR-340-5p with the MyD88 mRNA was confirmed via dual-luciferase reporter assay and RNA pull-down assay.

Results

The miR-340-5p overexpression partially alleviated the increase of the MyD88 level, impairment of cardiac function, and oxidative stress injury in the SIC animal model. In the SIC cell model, miR-340-5p mimic pretreatment partially relieved oxidative stress injury, while the miR-340-5p inhibitor had the opposite effect. Besides, the miR-340-5p mimic and inhibitor could reduce and further increase the MyD88 level in the SIC cell model, respectively. Dual-luciferase reporter and RNA pull-down experiments confirmed the interaction between the MyD88 mRNA and miR-340-5p. Finally, it was found that MyD88 siRNA pretreatment also partially alleviates the oxidative stress injury in the SIC cell model.

Conclusion

In sum, our study demonstrated that miR-340-5p can improve myocardial oxidative stress injury by targeting MyD88 in SIC.

Long noncoding RNA ANRIL up-regulates CCND1 via sponging miR-98-5p to promote TGF-β1-induced human airway smooth muscle cell proliferation, migration, and extracellular matrix deposition

Excessive proliferation and migration of airway smooth muscle cell (ASMC) contribute to asthma pathogenesis. Long noncoding RNAs (lncRNAs) are reported to take part in asthma pathogenesis. This study is targeted at deciphering the role of the lncRNA antisense noncoding RNA in the INK4 locus (ANRIL) in ASMC proliferation, migration and extracellular matrix (ECM) deposition. qRT-PCR was performed to determine ANRIL, miR-98-5p, and cyclin D1 (CCND1) mRNA expression levels in transforming growth factor-β1 (TGF-β1)-treated ASMCs. CCK-8 and Transwell assays were employed to examine ASMC proliferation and migration, respectively. Dual-luciferase reporter gene assay and RNA immunoprecipitation assay were carried out for analyzing the targeted relationship of miR-98-5p with ANRIL or CCND1 mRNA 3'-UTR. The levels of CCND1 and ECM proteins (such as fibronectin, COL3A1, and COL1A2) in ASMCs were detected through Western blot. In this work, we found that ANRIL and CCND1 were up-regulated in TGF-β1-treated ASMCs, whereas miR-98-5p was down-regulated. ANRIL overexpression facilitated the proliferation, ECM deposition and migration of TGF-β1-induced ASMCs, while knocking down ANRIL had the opposite effect. Furthermore, ANRIL targeted miR-98-5p directly, and CCND1 was miR-98-5p's downstream target. ANRIL indirectly increased CCND1 expression in ASMCs via competitively binding to miR-98-5p. MiR-98-5p inhibition or CCND1 overexpression counteracted the inhibiting effect that ANRIL knockdown had on TGF-β1-stimulated ASMC proliferation, migration and ECM deposition. In conclusion, ANRIL indirectly up-regulates CCND1 expression by targeting miR-98-5p to promote ASMC proliferation, migration and ECM deposition, thus facilitating the pathogenesis of asthma.

CCCTC-binding factor-mediated microRNA-340-5p suppression aggravates myocardial injury in rats with severe acute pancreatitis through activation of the HMGB1/TLR4 axis

BACKGROUND

Severe acute pancreatitis (SAP) is a life-threatening disorder associated with multisystem organ failure. This study aimed to investigate the function of high mobility group box 1 (HMGB1) in SAP-induced myocardial injury.

METHODS

A rat model with SAP was induced. The pathological changes in rat pancreatic and cardiac tissues were examined by HE staining. Cardiomyocyte apoptosis in rat cardiac tissues, and the serum levels of myocardial injury markers and pro-inflammatory cytokines were examined. Rat primary cardiomyocytes were treated with H₂O₂ for in vitro experiments. The regulatory molecules of HMGB1 were predicted by bioinformatics analysis. Altered expression of HMGB1, microRNA (miR)-340-5p and CCCTC-binding factor (CTCF) was introduced in rats or cells to investigate their roles in myocardial injury.

RESULTS

CTCF and HMGB1 were highly expressed but miR-340-5p was poorly expressed in cardiac tissues of rats with SAP. HMGB1 silencing reduced toll-like receptor 4 (TLR4) expression to promote proliferation and reduce apoptosis of H₂O₂-treated cardiomyocytes. miR-340-5p targeted HMGB1 mRNA, while CTCF suppressed miR-340-5p transcription. CTCF upregulation or miR-340-5p downregulation blocked the effects of HMGB1 silencing on cardiomyocytes. In vivo, CTCF silencing alleviated injury in rat pancreatic and cardiac tissues and reduced the expression of creatine kinase-MB (CK-MB), lactic dehydrogenase, interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) in rat serum. But further overexpression of HMGB1 or inhibition of miR-340-5p aggravated the symptoms in rats.

CONCLUSION

This study demonstrated that CTCF reduces transcription of miR-340-5p to promote HMGB1 expression, which activates TLR4 expression and promotes myocardial injury in rats with SAP.

The various regulatory functions of long noncoding RNAs in apoptosis, cell cycle, and cellular senescence

Long noncoding RNAs (lncRNAs) are a group of noncoding cellular RNAs involved in significant biological phenomena such as differentiation, cell development, genomic imprinting, adjusting the enzymatic activity, regulating chromosome conformation, apoptosis, cell cycle, and cellular senescence. The misregulation of lncRNAs interrupting normal biological processes has been implicated in tumor formation and metastasis, resulting in cancer. Apoptosis and cell cycle, two main biological phenomena, are highly conserved and intimately coupled mechanisms. Hence, some cell cycle regulators can influence both programmed cell death and cell division. Apoptosis eliminates defective and unwanted cells, and the cell cycle enables cells to replicate themselves. The improper regulation of apoptosis and cell cycle contributes to numerous disorders such as neurodegenerative and autoimmune diseases, viral infection, anemia, and mainly cancer. Cellular senescence is a tumor-suppressing response initiated by environmental and internal stress factors. This phenomenon has recently attained more attention due to its therapeutic implications in the field of senotherapy. In this review, the regulatory roles of lncRNAs on apoptosis, cell cycle, and senescence will be discussed. First, the role of lncRNAs in mitochondrial dynamics and apoptosis is addressed. Next, the interaction between lncRNAs and caspases, pro/antiapoptotic proteins, and also EGFR/PI3K/PTEN/AKT/mTORC1 signaling pathway will be investigated. Furthermore, the effect of lncRNAs in the cell cycle is surveyed through interaction with cyclins, cdks, p21, and wnt/β-catenin/c-myc pathway. Finally, the function of essential lncRNAs in cellular senescence is mentioned.

miR-340-5p Mediates Cardiomyocyte Oxidative Stress in Diabetes-Induced Cardiac Dysfunction by Targeting Mcl-1

Diabetic cardiomyopathy (DCM) is initially characterized by early diastolic dysfunction, left ventricular remodeling, hypertrophy, and myocardial fibrosis, and it is eventually characterized by clinical heart failure. MicroRNAs (miRNAs), endogenous small noncoding RNAs, play significant roles in diabetes mellitus (DM). However, it is still largely unknown about the mechanism that links miRNAs and the development of DCM. Here, we aimed to elucidate the mechanism underlying the potential role of microRNA-340-5p in DCM in db/db mouse, which is a commonly used model of type 2 DM and diabetic complications that lead to heart failure. We first demonstrated that miR-340-5p expression was dramatically increased in heart tissues of mice and cardiomyocytes under diabetic conditions. Overexpression of miR-340-5p exacerbated DCM, which was reflected by extensive myocardial fibrosis and more serious dysfunction in db/db mice as represented by increased apoptotic cardiomyocytes, elevated ROS production, and impaired mitochondrial function. Inhibition of miR-340-5p by a tough decoy (TUD) vector was beneficial for preventing ROS production and apoptosis, thus rescuing diabetic cardiomyopathy. We identified myeloid cell leukemia 1 (Mcl-1) as a major target gene for miR-340-5p and showed that the inhibition of Mcl-1 was responsible for increased functional loss of mitochondria, oxidative stress, and cardiomyocyte apoptosis, thereby caused cardiac dysfunction in diabetic mice. In conclusion, our results showed that miR-340-5p plays a crucial role in the development of DCM and can be targeted for therapeutic intervention.

Long non-coding RNA growth arrest specific transcript 5 acting as a sponge of MicroRNA-188-5p to regulate SMAD family member 2 expression promotes myocardial ischemia-reperfusion injury

The purpose of this work is to probe into the potential role of long non-coding RNA growth arrest specific transcript 5 (lncGAS5)/ microRNA (miR)-188-5p/SMAD2 axis in MIRI. Through ligating the left anterior descending (LAD) coronary artery, MIRI animal model and hypoxia/reoxygenation (H/R) myocardial injury model in vitro were established. Via adenovirus or plasmid transfection, lncGAS5/MiR-188-5p/SMAD2 expression was up-regulated or down-regulated in the study. RT-qPCR was applied to check LncGAS5/MiR-188-5p/SMAD2 mRNA expression, HE staining for histopathological staining, TUNEL staining and flow cytometry to examine cardiomyocyte apoptotic rate, CCK-8 to check cell viability, ELISA to detect inflammatory factor levels, Western blot to examine Bax, Bcl-2, cleaved caspase-3, NF-κB and SMAD2 expression, and dual luciferase reporter experiment to examine the targeting relationship of miR-188-5p with LncGAS5 and SMAD2. The results indicated that LncGAS5 and SMAD2 were highly expressed in MIRI and miR-188-5p was under-expressed. Silencing LncGAS5 and SMAD2 or overexpressing miR-188-5p could reduce MIRI in myocardial tissue, cardiomyocyte apoptosis, inhibit Bax, cleaved caspase-3 and NF-κB expressions and promote Bcl-2 expression, while reducing inflammatory factors TNF -α, IL-1β and IL-6 levels. Overexpressing LncGAS5 promoted MIRI. Additionally, the impact of silencing LncGAS5 on MIRI could be reversed through inhibiting miR-188-5p. LncGAS5 acted as a sponge of miR-188-5p to target SMAD2 expression. In conclusion, Silencing LncGAS5 is available to improve MIRI through regulating miR-188-5p/SMAD2 axis, and may be used as a potential target for treating MIRI in the future.

LncRNA TUG1 attenuates ischaemia-reperfusion-induced apoptosis of renal tubular epithelial cells by sponging miR-144-3p via targeting Nrf2

Renal ischaemia/reperfusion (I/R) injury may induce kidney damage and dysfunction, in which oxidative stress and apoptosis play important roles. Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are reported to be closely related to renal I/R, but the specific molecular mechanism is still unclear. The purpose of this research was to explore the regulatory effect of lncRNA TUG1 on oxidative stress and apoptosis in renal I/R injury. This research revealed that in renal I/R injury and hypoxia/reperfusion (H/R) injury in vitro, the expression level of lncRNA TUG1 was upregulated, and oxidative stress levels and apoptosis levels were negatively correlated with the expression level of lncRNA TUG1. Using bioinformatics databases such as TargetScan and microRNA.org, microRNA-144-3p (miR-144-3p) was predicted to be involved in the association between lncRNA TUG1 and Nrf2. This study confirmed that the level of miR-144-3p was significantly reduced following renal I/R injury and H/R injury in vitro, and miR-144-3p was determined to target Nrf2 and inhibit its expression. In addition, lncRNA TUG1 can reduce the inhibitory effect of miR-144-3p on Nrf2 by sponging miR-144-3p. In summary, our research shows that lncRNA TUG1 regulates oxidative stress and apoptosis during renal I/R injury through the miR-144-3p/Nrf2 axis, which may be a new treatment target for renal I/R injury.