LncRNA SNHG1 alleviates hypoxia-reoxygenation-induced vascular endothelial cell injury as a competing endogenous RNA through the HIF-1α/VEGF signal pathway

Pathological roles of mitochondrial dysfunction in endothelial cells during the cerebral no-reflow phenomenon: A review

Emergency intravascular interventional therapy is the most effective approach to rapidly restore blood flow and manage occlusion of major blood vessels during the initial phase of acute ischemic stroke. Nevertheless, several patients continue to experience ineffective reperfusion or cerebral no-reflow phenomenon, that is, hypoperfusion of cerebral blood supply after treatment. This is primarily attributed to downstream microcirculation disturbance. As integral components of the cerebral microvascular structure, endothelial cells (ECs) attach importance to regulating microcirculatory blood flow. Unlike neurons and microglia, ECs harbor a relatively low abundance of mitochondria, acting as key sensors of environmental and cellular stress in regulating the viability, structural integrity, and function of ECs rather than generating energy. Mitochondria dysfunction including increased mitochondrial reactive oxygen species levels and disturbed mitochondrial dynamics causes endothelial injury, further causing microcirculation disturbance involved in the cerebral no-reflow phenomenon. Therefore, this review aims to discuss the role of mitochondrial changes in regulating the role of ECs and cerebral microcirculation blood flow during I/R injury. The outcomes of the review will provide promising potential therapeutic targets for future prevention and effective improvement of the cerebral no-reflow phenomenon.

Plasma exosomes from patients with coronary artery disease promote atherosclerosis via impairing vascular endothelial junctions

The underlying mechanism of vascular endothelial hyperpermeability caused by decrease of endothelial junctions occurring in atherosclerosis remains elusive. Our findings identified that plasma exosomes from patients with stable coronary artery disease (ExoSCAD) contain differentially expressed miRNAs that are clustered with genes related to cell junctions, prompting us to investigate the role of ExoSCAD in regulating vascular endothelial junctions and to elucidate the underlying mechanisms. Here, we show that ExoSCAD markedly impair vascular endothelial junctions via suppressing VE-Cadherin and ZO-1 in endothelial cells in vitro and in vivo, consequently increases endothelial permeability. Critically, exosomal miR-140-3p plays a crucial role in ExoSCAD-induced inhibition of ZO-1, and may be an important causative factor in the development of endothelial hyperpermeability during atherosclerosis. Additionally, exosomal miR-140-3p level coordinates with severity of SCAD. Targeting miR-140-3p in circulating exosomes might open novel options for treatment of atherosclerosis.

Long Non-Coding RNA PVT1 Facilitates Radiation-Induced Vascular Endothelial Cell Injury through Sponging MicroRNA-9-5p

Radiotherapy is a common therapeutic strategy for various solid tumors, with vascular endothelial injury being a common side effect. The study aimed to examine the effect of long non-coding RNA PVT1 on radiation-induced vascular endothelial cell injury, and explore the possible underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were exposed to different doses of X ray to mimic radiation. LncRNA and miRNA levels were detected via qRT-PCR. Interaction between lncRNA and miRNAs was determined through dual-luciferase reporter assay. Statistical processing was conducted using student's t test between two groups and one-way ANOVA among multiple groups, and P < 0.05 means a significant difference. GO and KEGG were performed for the function and pathway enrichment analysis. LncRNA PVT1 elevated along with the increase of radiation dose in HUVECs. Poorly expressed lncRNA PVT1 promotes cell viability and inhibits oxidative stress. PVT1 serves as a competitive endogenous RNA (ceRNA) of miR-9-5p. miR-9-5p inhibitor inverted the influence of PVT1 knockdown on radiation-stimulated cell apoptosis and oxidative stress in HUVECs. KEGG analysis identified significant enrichment of the MAPK signaling pathway among overlapping target genes of miR-9-5p. LncRNA PVT1 knockdown alleviated radiation-induced vascular endothelial injury via sponging miR-9-5p. The underlying mechanism might be probably MAPK signaling-related.

LncRNAs Are Key Regulators of Transcription Factor-Mediated Endothelial Stress Responses

The functional role of long noncoding RNAs in the endothelium is highly diverse. Among their many functions, regulation of transcription factor activity and abundance is one of the most relevant. This review summarizes the recent progress in the research on the lncRNA-transcription factor axes and their implications for the vascular endothelium under physiological and pathological conditions. The focus is on transcription factors critical for the endothelial response to external stressors, such as hypoxia, inflammation, and shear stress, and their lncRNA interactors. These regulatory interactions will be exemplified by a selected number of lncRNAs that have been identified in the endothelium under physiological and pathological conditions that are influencing the activity or protein stability of important transcription factors. Thus, lncRNAs can add a layer of cell type-specific function to transcription factors. Understanding the interaction of lncRNAs with transcription factors will contribute to elucidating cardiovascular disease pathologies and the development of novel therapeutic approaches.

Exosomal circ_0084043 derived from colorectal cancer-associated fibroblasts promotes in vitro endothelial cell angiogenesis by regulating the miR-140-3p/HIF-1α/VEGF signaling axis

Background

Circular RNAs (circRNAs) hold potential as diagnostic markers for colorectal cancer (CRC); however, their functional mechanisms remain incompletely elucidated. This work investigates the clinical implications of a unique set comprising six circRNAs derived from serum in CRC. Furthermore, we delve into the role of exosomal circ_0084043, originating from colorectal cancer-associated fibroblasts (CAFs), with a specific focus on its contribution to endothelial cell angiogenesis.

Methods

The study analyzed circRNA levels in serum samples obtained from both CRC and control groups using qRT-PCR. Additionally, exosomes originating from colorectal CAFs and normal fibroblasts (NFs) were purified and confirmed by electron microscopy and Western blotting techniques. The proangiogenic effects of CAF-derived exosomal circ_0084043 were assessed in endothelial cells through proliferation, migration, and in vitro capillary tube formation assays. Gain- and loss-of-function experiments were employed to clarify the role of the circ_0084043/miR-140-3p/HIF-1α axis in endothelial cell angiogenesis, utilizing luciferase reporter assay, Western blotting, and ELISA for mechanism elucidation.

Results

The candidate circRNAs (circ_0060745, circ_001569, circ_007142, circ_0084043, Circ_BANP, and CiRS-7) exhibited notably elevated expression in CRC patient sera compared to the levels observed in healthy individuals. Except for CiRS-7, all circRNAs showed elevated expression in CRC patients with positive lymph node metastasis and advanced tumor stages. Exosomes released by colorectal CAFs augmented endothelial cell proliferation, migration, and angiogenesis by upregulating VEGF expression and secretion. Circ_0084043 was highly detected in endothelial cells treated with CAF-derived exosomes. Silencing circ_0084043 reduced VEGFA expression and diminished CAF exosome-induced endothelial cell processes, indicating its pivotal role in angiogenesis. Circ_0084043 sponges miR-140-3p, regulating HIF-1α, and a reverse relationship was also identified between miR-140-3p and VEGFA in endothelial cells. Inhibiting miR-140-3p mitigated circ_0084043 knockdown effects in CAF exosome-treated endothelial cells. Co-transfection of si-circ_0084043 and a miR-140-3p inhibitor reversed the inhibited migration and angiogenesis caused by circ_0084043 knockdown in CAF exosome-treated endothelial cells. Inhibiting miR-140-3p rescued reduced VEGFA expression due to circ_0084043 knockdown in endothelial cells exposed to CAF-derived exosomes, indicating modulation of the circ_0084043/miR-140-3p/VEGF signaling in CAF-derived exosome-induced angiogenesis.

Conclusions

This study unveiled a distinctive signature of six serum-derived circular RNAs, indicating their potential as promising diagnostic biomarkers for CRC. Importantly, exosomal circ_0084043 originating from colorectal CAFs was identified as playing a crucial role in endothelial cell angiogenesis, exerting its influence through the modulation of the miR-140-3p/HIF-1α/VEGF signaling axis.

The Long Non-Coding RNA SNHG1 Predicts Severity of Acute Pancreatitis and Stimulates Pancreatic Cell Apoptosis and Inflammatory Response

Acute pancreatitis (AP) is a common digestive emergency, needs early prediction and recognition. The study examined the clinical value of long non-coding RNA SNHG1 in AP, and explored its related mechanism for AP. A total of 288 AP cases and 150 healthy persons were recruited, the AP patients were grouped based on AP severity. AR42J cells were treated with 100nM caerulein to stimulate AP in vitro. qRT-PCR was performed for mRNA detection. Receiver operating characteristic (ROC) curve was drawn for diagnostic significance evaluation. The relationship of SNHG1 and miR-140-3p was verified via luciferase reporter and RNA immunoprecipitation (RIP) assay. AP cases had high expression of SNHG1, and it can differentiate AP cases from healthy people with the area under the curve (AUC) of 0.899. Severe AP cases had high values of SNHG1, which was independently related to AP severity. SNHG1 knockdown relieved caerulein-induced AR42J cell apoptosis and inflammatory response. miR-140-3p interacted with SNHG1, and reversed the role of SNHG1 in caerulein-induced AR42J cell injury. RAB21 was a candidate target of miR-140-3p, and was at high expression in AP cell models. SNHG1 may be a promising biomarker for the detection of AP, and serves as a potential biological marker for further risk stratification in the management of AP. SNHG1 knockdown can relieve inflammatory responses and pancreatic cell apoptosis by absorbing miR-140-3p.

SNHG1/miR-21 axis mediates the cardioprotective role of aloin in sepsis through modulating cardiac cell viability and inflammatory responses

BACKGROUND

Aloin has cardioprotective effects, however, its cardioprotective role in sepsis remains unclear. This study aimed to analyze whether aloin could prevent sepsis-related myocardial damage and explore the underlying mechanisms by examining the expression of long-noncoding RNA (lncRNA) SNHG1 and microRNA-21 (miR-21).

METHODS

The interaction of SNHG1 with miR-21 was identified by dual-luciferase reporter assay. The levels of SNHG1 and miR-21 were measured by real-time quantitative PCR. The cardioprotective function of aloin was assessed in a sepsis animal model, which was induced by cecal ligation and puncture, and in a myocardial injury cell model in H9C2 cells stimulated by lipopolysaccharide. Myocardial injury biomarker levels and hemodynamic indicators in mice model were measured to evaluate cardiac function. The viability of H9C2 cells was assessed by cell counting kit-8 assay. Inflammatory cytokine levels were examined by an ELISA method.

RESULTS

Decreased SNHG1 and increased miR-21 were found in sepsis patients with cardiac dysfunction, and they were negatively correlated. Aloin significantly attenuated myocardial damage and inflammatory responses of mice model, and increased the viability and suppressed inflammation in H9C2 cell model. In addition, SNHG1 expression was upregulated and miR-21 expression was downregulated by aloin in both mice and cell models. Moreover, in mice and cell models, SNHG1/miR-21 axis affected sepsis-related myocardial damage, and mediated the cardioprotective effects of aloin.

CONCLUSION

Our findings indicated that aloin exerts protective effects in sepsis-related myocardial damage through regulating cardiac cell viability and inflammatory responses via regulating the SNHG1/miR-21 axis.

The role of PI3K/AKT signaling pathway in myocardial ischemia-reperfusion injury

Myocardial ischemia has a high incidence and mortality rate, and reperfusion is currently the standard intervention. However, reperfusion may lead to further myocardial damage, known as myocardial ischemia/reperfusion injury (MIRI). There are currently no effective clinical treatments for MIRI. The PI3K/Akt signaling pathway is involved in cardiovascular health and disease and plays an important role in reducing myocardial infarct size and restoring cardiac function after MIRI. Activation of the PI3K/Akt pathway provides myocardial protection through synergistic upregulation of antioxidant, anti-inflammatory, and autophagy activities and inhibition of mitochondrial dysfunction and cardiomyocyte apoptosis. Many studies have shown that PI3K/Akt has a significant protective effect against MIRI. Here, we reviewed the molecular regulation of PI3K/Akt in MIRI and summarized the molecular mechanism by which PI3K/Akt affects MIRI, the effects of ischemic preconditioning and ischemic postconditioning, and the role of related drugs or activators targeting PI3K/Akt in MIRI, providing novel insights for the formulation of myocardial protection strategies. This review provides evidence of the role of PI3K/Akt activation in MIRI and supports its use as a therapeutic target.

The Expression Levels of MicroRNAs Differentially Expressed in Sudden Sensorineural Hearing Loss Patients' Serum Are Unchanged for up to 12 Months after Hearing Loss Onset

Sudden sensorineural hearing loss (SSNHL) is an acquired idiopathic hearing loss. Serum levels of small, non-coding RNAs and microRNAs (miRNAs) miR-195-5p/-132-3p/-30a-3p/-128-3p/-140-3p/-186-5p/-375-3p/-590-5p are differentially expressed in SSNHL patients within 28 days of hearing loss onset. This study determines if these changes persist by comparing the serum miRNA expression profile of SSNHL patients within 1 month of hearing loss onset with that of patients 3-12 months after hearing loss onset. We collected serum from consenting adult SSNHL patients at presentation or during clinic follow-up. We matched patient samples drawn 3-12 months after hearing loss onset (delayed group, n = 9 patients) by age and sex to samples drawn from patients within 28 days of hearing loss onset (immediate group, n = 14 patients). We compared the real-time PCR-determined expression levels of the target miRNAs between the two groups. We calculated the air conduction pure-tone-averaged (PTA) audiometric thresholds in affected ears at the initial and final follow-up visits. We undertook inter-group comparisons of hearing outcome status and initial and final PTA audiometric thresholds. There was no significant inter-group difference in miRNA expression level, hearing recovery status and initial and final affected ear PTA audiometric thresholds.

HOTAIR regulates SIRT3-mediated cardiomyocyte survival after myocardial ischemia/reperfusion by interacting with FUS

BACKGROUND

Myocardial ischemia/reperfusion (I/R) contributes to serious myocardial injury and even death. Therefore, prevention and mitigation of myocardial I/R is particularly important. LncRNA HOTAIR has been reported to be implicated in myocardial I/R progression. However, the detailed molecular mechanism of HOTAIR in cardiomyocyte was explored in myocardial I/R.

METHODS

Firstly, cell model of myocardial I/R was established through hypoxia/reoxygenation (H/R). Apoptosis and cell cycle were evaluated utilizing flow cytometry. The corresponding test kits were conducted to monitor the levels of LDH, Caspase3 and Caspase9. The gene expression and protein levels were detected by qPCR and western blot, respectively. RNA pull-down and RIP were performed to verify the interaction between FUS and lncRNA HOTAIR.

RESULTS

In AC16 cardiomyocytes treated with H/R, lncRNA HOTAIR and SIRT3 expression were obviously decreased. Overexpression of HOTAIR or SIRT3 could ameliorate H/R-induced cardiomyocyte injury by promoting cell viability, lowering LDH levels, and suppressing cell apoptosis. Further, lncRNA HOTAIR upregulated the expression of SIRT3 via interacting with FUS, thereby promoting the survival of H/R-injured cardiomyocytes.

CONCLUSION

LncRNA HOTAIR can improve myocardial I/R by affecting cardiomyocyte survival through regulation of SIRT3 by binding to the RNA binding protein FUS.

MiR-140-3p directly targets Tyro3 to regulate OGD/R-induced neuronal injury through the PI3K/Akt pathway

BACKGROUND AND PURPOSE

MicroRNAs (miRNAs) are highly expressed in the central nervous system and play important roles in ischaemic stroke pathogenesis. However, the role of miRNAs in cerebral ischaemia-reperfusion injury remains unclear. Here, we investigated the role of miR-140-3p in regulating oxygen-glucose deprivation/reoxygenation (OGD/R)-induced neuronal injury in vitro to identify a new biomarker for research on ischaemic stroke.

METHODS

The differential expression of miR-140-3p and Tyro3 in OGD/R-exposed N2a cells was verified by qRT-PCR. N2a cells were transfected with miR-140-3p mimic, miR-140-3p inhibitor, Tyro3 or siTyro3, and qRT-PCR, Western blotting, the Cell counting kit-8 (CCK-8) assay, Hoechst 33342/PI staining and flow cytometry analyses were performed to measure miRNA, mRNA and protein expression; cell viability; and apoptosis.

RESULTS

OGD/R-exposed N2a cells exhibited increased miR-140-3p expression, decreased viability, reduced Bcl-2 protein expression and increased Bax and Caspase-3 protein expression and apoptosis; the miR-140-3p mimic markedly amplified these changes, exacerbating OGD/R-induced injury to N2a cells, while the miR-140-3p inhibitor reversed these changes and alleviated OGD/R-induced injury. OGD/R-exposed N2a cells expressed less Tyro3, and Tyro3 overexpression increased cell viability and Bcl-2 protein expression, reduced Bax and Caspase-3 protein expression, and alleviated OGD/R-induced injury. However, silencing Tyro3 reversed these changes and exacerbated OGD/R-induced injury. MiR-140-3p directly bound the Tyro3 mRNA 3'UTR. Rescue experiments indicated that the miR-140-3p mimic-induced changes in cell viability and protein expression were alleviated by Tyro3 overexpression and that the miR-140-3p inhibitor-induced changes in cell viability and protein expression were alleviated by silencing Tyro3. Tyro3 overexpression increased cell viability and PI3K and p-Akt protein expression, but these effects were weakened by the addition of LY294002.

CONCLUSIONS

MiR-140-3p directly targets Tyro3 to regulate cell viability and apoptosis of OGD/R-exposed N2a cells through the PI3K/Akt pathway, suggesting that miR-140-3p is a novel biomarker and therapeutic target for ischaemic stroke.

Chemerin-Induced Down-Regulation of Placenta-Derived Exosomal miR-140-3p and miR-574-3p Promotes Umbilical Vein Endothelial Cells Proliferation, Migration, and Tube Formation in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) leads to poor pregnancy outcomes and fetoplacental endothelial dysfunction; however, the underlying mechanisms remain unknown. This study aimed to investigate the effect of placenta-derived exosomal miRNAs on fetoplacental endothelial dysfunction in GDM, as well as to further explore the role of chemerin to this end. Placenta-derived exosomal miR-140-3p and miR-574-3p expression (next-generation sequencing, quantitative real-time PCR), its interactions with cell function (Cell Counting Kit-8, Transwell, tube formation assay), chemerin interactions (Western blotting), and placental inflammation (immunofluorescence staining, enzyme-linked immunosorbent assay) were investigated. Placenta-derived exosomal miR-140-3p and miR-574-3p were downregulated in GDM. Additionally, miR-140-3p and miR-574-3p inhibited the proliferation, migration, and tube formation ability of umbilical vein endothelial cells by targeting vascular endothelial growth factor. Interestingly, miR-140-3p and miR-574-3p expression levels were negatively correlated with chemerin, which induced placental inflammation through the recruitment of macrophage cells and release of IL-18 and IL-1β. These findings indicate that chemerin reduces placenta-derived exosomal miR-140-3p and miR-574-3p levels by inducing placental inflammation, thereby promoting the proliferation, migration, and tube formation of umbilical vein endothelial cells in GDM, providing a novel perspective on the underlying pathogenesis and therapeutic targets for GDM and its offspring complications.

Long noncoding RNA TDRG1 aggravates doxorubicin-induced cardiomyopathy by binding with miR-873-5p to upregulate PRKAR2

Doxorubicin-induced cardiomyopathy (DCM) is a life-threatening event. The long noncoding RNAs (lncRNAs) have been reported with close associations with DCM, which may provide novel insight into pathophysiological mechanisms of DCM. DCM rat model and cell models were established using doxorubicin. Echocardiography analyses were performed to assess cardiac function. We found that testis developmental-related gene 1 (TDRG1) expression was upregulated in DCM rats and in doxorubicin-treated human umbilical vein endothelial cells (HUVECs). TDRG1 knockdown enhanced cell viability, promoted tube formation, and inhibited apoptosis of doxorubicin-treated HUVECs. Additionally, knockdown of TDRG1 alleviated cardiac injury in DCM rats. Mechanistically, miR-873-5p was identified to bind with TDRG1. In addition, protein kinase cAMP-dependent type II regulatory subunit alpha (PRKAR2) was confirmed to bind with miR-873-5p as a target mRNA. MiR-873-5p negatively regulated PRKAR2 mRNA and protein levels. At last, rescue assays indicated that the overexpression of PRKAR2 restored the effect of TDRG1 knockdown on doxorubicin-treated HUVEC angiogenesis and apoptosis. To conclude, TDRG1 aggravates DCM progression by binding with miR-873-5p to upregulate PRKAR2. This work suggested the potential of TDRG1 as a target for DCM treatment.

miR-140-3p suppresses the proliferation and migration of macrophages

Macrophages benefit myelin debris removal, blood vessel formation, and Schwann cell activation following peripheral nerve injury. Identifying factors that modulate macrophage phenotype may advantage the repair and regeneration of injured peripheral nerves. microRNAs (miRNAs) are important regulators of many physiological and pathological processes, including peripheral nerve regeneration. Herein, we investigated the regulatory roles of miR-140-3p, a miRNA that was differentially expressed in injured rat sciatic nerves, in macrophage RAW264.7 cells. Observations from EdU proliferation assay demonstrated that elevated miR-140-3p decreased the proliferation rates of RAW264.7 cells while suppressed miR-140-3p increased the proliferation rates of RAW264.7 cells. Transwell-based migration assay showed that up-regulated and down-regulated miR-140-3p led to elevated and reduced migration abilities, respectively. However, the abundances of numerous phenotypic markers of M1 and M2 macrophages were not significantly altered by miR-140-3p mimic or inhibitor transfection. Bioinformatic analysis and miR-140-3p-induced gene suppression examination suggested that Smad3 might be the target gene of miR-140-3p. These findings illuminate the inhibitory effects of miR-140-3p on the proliferation and migration of macrophages and contribute to the cognition of the essential roles of miRNAs during peripheral nerve regeneration.

Genetic variants of the hypoxia-inducible factor 3 alpha subunit (Hif3a) gene in the Fat and Lean mouse selection lines

BACKGROUND

Adipose tissue hypoxia and members of the hypoxia-inducible factor alpha (HIFA) are involved in development of obesity. However, the mechanism and functions of HIF3A, one of three HIFA paralogs, in fat deposition have not been sufficiently studied.

METHODS AND RESULTS

In the present study, we investigated whether Hif3a sequence variants are associated with divergent fat deposition in mouse selection lines for fatness and leanness. Sequencing and RFLP were used to analyse sequence variants within Hif3a. To identify candidate regulatory variants, we performed literature screening and used databases and bioinformatics tools like Ensembl, MethPrimer, TargetScanMouse, miRDB, PolyAsite, RISE, LncRRIsearch, RNAfold, PredictProtein, CAIcal, and switches.ELM Resource. There are 90 sequence variants in Hif3a between the two mouse lines. While most Fat line variants locate within intronic regions, Lean line variants are mainly in 3' UTR. We constructed a map of Hif3a potential regulatory regions and identified 39 regulatory variants by integrating data on constrained and regulatory elements, CpGs, and miRNAs and lncRNAs binding sites. Moreover, 3' UTR and two exonic variants may influence mRNA stability, translation rate and protein functionality. We propose as priority candidates for further functional studies a missense (rs37398126) and synonymous (rs37739792) variants, and intronic (rs47471302) variant that overlap conserved element in promoter region and predicted lncRNAs binding site.

CONCLUSION

The results indicate a potential involvement of Hif3a in fat deposition. Additionally, approach used in the present study may serve as a general guideline for constructing an integrative gene map for prioritizing candidate gene variants with phenotypic effects.

Role and mechanism of the lncRNA SNHG1/miR‑450b‑5p/IGF1 axis in the regulation of myocardial ischemia reperfusion injury

The increasing rates of morbidity and mortality caused by ischemic heart disease pose a serious threat to human health. Long non‑coding (lnc)RNA small nucleolar RNA host gene 1 (SNHG1) has a protective effect on the myocardium. In the present study, the role of lncRNA SNHG1 in myocardial ischemia reperfusion injury (MIRI) and the underlying mechanisms were investigated. After hypoxia/reoxygenation (H/R) induction, the expression levels of lncRNA SNHG1 were detected using reverse transcription‑quantitative PCR. After lncRNA SNHG1 overexpression via cell transfection, cell viability was detected using an MTT assay, apoptotic rates were detected using TUNEL staining, apoptosis‑related protein expression levels were detected using western blotting and respective kits were used to measure the oxidative stress levels. The Encyclopedia of RNA Interactomes database predicted the presence of binding sites between lncRNA SNHG1 and microRNA (miR)‑450b‑5p, and between miR‑450b‑5p and insulin‑like growth factor 1 (IGF1). These interactions were then verified using luciferase reporter assays. Subsequently, the regulatory mechanism underlying the lncRNA SNHG1/miR‑450b‑5p/IGF1 axis in MIRI was investigated by overexpressing miR‑450b‑5p and knocking down IGF1 expression in H/R‑induced cells. Finally, the expression of PI3K/Akt signaling pathway‑related proteins was detected using western blotting. lncRNA SNHG1 expression was significantly downregulated in H/R‑induced AC16 cells. lncRNA SNHG1 overexpression significantly inhibited apoptosis and decreased oxidative stress levels in H/R‑induced AC16 cells, which was mediated via regulation of the miR‑450b‑5p/IGF1 axis and activation of the PI3K/Akt signaling pathway. Therefore, the present study suggested that activation of the PI3K/Akt signaling pathway via the lncRNA SNHG1/miR‑450b‑5p/IGF1 axis inhibited the apoptosis and oxidative stress levels of H/R‑induced AC16 cells.

LncSNHG1 Promoted CRC Proliferation through the miR-181b-5p/SMAD2 Axis

Objective

To investigate the effects of LncRNA SNHG1 on the proliferation, migration, and epithelial-mesenchymal transition (EMT) of colorectal cancer cells (CRCs).

Methods

4 pairs of CRC tissue samples and their corresponding adjacent samples were analyzed by the human LncRNA microarray chip. The expression of LncSNHG1 in CRC cell lines was verified by qRT-PCR. Colony formation assays and CCK8 assays were applied to study the changes in cell proliferation. The transwell assay and wound healing experiments were used to verify the cell invasion and migration. EMT progression was confirmed finally.

Results

LncSNHG1 was overexpressed both in CRC tissues and cell lines, while the miR-181b-5p expression was decreased in CRC cell lines. After knock-down of LncSNHG1, the proliferation, invasion, and migration of HT29 and SW620 cells were all decreased. Meanwhile, LncSNHG1 enhanced EMT progress through regulation of the miR-181b-5p/SMAD2 axis.

Conclusion

LncSNHG1 promotes colorectal cancer cell proliferation and invasion through the miR-181b-5p/SMAD2 axis.

Extracorporeal Cardiac Shock Wave-Induced Exosome Derived From Endothelial Colony-Forming Cells Carrying miR-140-3p Alleviate Cardiomyocyte Hypoxia/Reoxygenation Injury via the PTEN/PI3K/AKT Pathway

Background: Stem cell-derived exosomes have great potential in the treatment of myocardial ischemia–reperfusion injury (IRI). Extracorporeal cardiac shock waves (ECSW) as effective therapy, in part, could activate the function of exosomes. In this study, we explored the effect of ECSW-induced exosome derived from endothelial colony-forming cells on cardiomyocyte hypoxia/reoxygenation (H/R) injury and its underlying mechanisms.

Methods: The exosomes were extracted and purified from the supernatant of endothelial colony-forming cells (ECFCs-exo). ECFCs-exo treated with shock wave (SW-exo) or without shock wave (CON-exo) were performed with high-throughput sequencing of the miRNA. H9c2 cells were incubated with SW-exo or CON-exo after H/R injury. The cell viability, cell apoptosis, oxidative stress level, and inflammatory factor were assessed. qRT-PCR was used to detect the expression levels of miRNA and mRNA in cells and exosomes. The PTEN/PI3K/AKT pathway-related proteins were detected by Western blotting, respectively.

Results: Exosomes secreted by ECFCs could be taken up by H9c2 cells. Administration of SW-exo to H9c2 cells after H/R injury could significantly improve cell viability, inhibit cell apoptosis, and downregulate oxidative stress level (p < 0.01), with an increase in Bcl-2 protein and a decrease in Bax, cleaved caspase-3, and NF-κB protein (p < 0.05). Notably, miR-140-3p was found to be highly enriched both in ECFCs and ECFCs-exo treated with ECSW (p < 0.05) and served as a critical mediator. SW-exo increased miR-140-3p expression but decreased PTEN expression in H9c2 cells with enhanced phosphorylation of the PI3K/AKT signaling pathway. These cardioprotective effects of SW-exo on H/R injury were blunted by the miR-140-3p inhibitor. Dual-luciferase assay verified that miR-140-3p could directly target the 3′UTR of PTEN mRNA and exert a negative regulatory effect.

Conclusion: This study has shown the potential of ECSW as an effective stimulation for the exosomes derived from ECFCs in vitro. SW-exo exerted a stronger therapeutic effect on H/R injury in H9c2 cells possibly via delivering exosomal miR-140-3p, which might be a novel promising strategy for the myocardial IRI.

miR-140-3p enhanced the osteo/odontogenic differentiation of DPSCs via inhibiting KMT5B under hypoxia condition

Human dental pulp stem cells (DPSCs) have emerged as an important source of stem cells in the tissue engineering, and hypoxia will change various innate characteristics of DPSCs and then affect dental tissue regeneration. Nevertheless, little is known about the complicated molecular mechanisms. In this study, we aimed to investigate the influence and mechanism of miR-140-3p on DPSCs under hypoxia condition. Hypoxia was induced in DPSCs by Cobalt chloride (CoCl₂) treatment. The osteo/dentinogenic differentiation capacity of DPSCs was assessed by alkaline phosphatase (ALP) activity, Alizarin Red S staining and main osteo/dentinogenic markers. A luciferase reporter gene assay was performed to verify the downstream target gene of miR-140-3p. This research exhibited that miR-140-3p promoted osteo/dentinogenic differentiation of DPSCs under normoxia environment. Furthermore, miR-140-3p rescued the CoCl₂-induced decreased osteo/odontogenic differentiation potentials in DPSCs. Besides, we investigated that miR-140-3p directly targeted lysine methyltransferase 5B (KMT5B). Surprisingly, we found inhibition of KMT5B obviously enhanced osteo/dentinogenic differentiation of DPSCs both under normoxia and hypoxia conditions. In conclusion, our study revealed the role and mechanism of miR-140-3p for regulating osteo/dentinogenic differentiation of DPSCs under hypoxia, and discovered that miR-140-3p and KMT5B might be important targets for DPSC-mediated tooth or bone tissue regeneration.

Positive feedback loop of lncRNA SNHG1/miR‑16‑5p/GATA4 in the regulation of hypoxia/reoxygenation‑induced cardiomyocyte injury

Numerous studies have demonstrated that long non-coding RNAs (lncRNAs) serve an important regulatory role in ischemic injury of cardiomyocytes. lncRNA small nucleolar RNA host gene 1 (SNHG1) could effectively protect cardiomyocytes against various injuries. However, the role of SNHG1 in ischemic cardiomyocyte injury is unclear. It was hypothesized that SNHG1 may have a protective effect on cardiomyocyte injury induced by hypoxia/reoxygenation (H/R) by sponging microRNA (miRNA/miR). The purpose of the present study was to explore the role and molecular mechanism of SNHG1 in ischemic cardiomyocyte injury. A H9c2 cardiomyocyte H/R model was established. The expression levels of SNHG1 in cardiomyocytes treated with H/R were detected using reverse transcription-quantitative PCR. A luciferase reporter assay was used to analyze the associations among SNHG1, miR-16-5p and GATA binding protein 4 (GATA4). Chromatin immunoprecipitation experiments were performed to analyze the interaction between SNHG1 and GATA4. Cell Counting Kit-8, enzyme-linked immunosorbent assay, terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling and western blotting experiments were used to detect cell activity, lactate dehydrogenase release, apoptosis and apoptosis-related proteins (Bcl-2, Bax, Cleaved caspase-3 and Cleaved caspase-9), respectively. The expression levels of SNHG1 were downregulated in cardiomyocytes treated with H/R. Overexpression of SNHG1 had a protective effect on cardiomyocyte injury induced by H/R. In addition, SNHG1 could regulate the expression levels of GATA4 via sponging of miR-16-5p. Further experiments revealed that GATA4 could bind to the promoter region of SNHG1 and subsequently regulated the expression levels of SNHG1, indicating the important role of the positive feedback loop of SNHG1/miR-16-5p/GATA4 in cardiomyocyte ischemic injury. To conclude, the present study revealed the protective effect of the SNHG1/miR-16-5p/GATA4 positive feedback loop on cardiomyocyte injury induced by H/R and provided a potential therapeutic target for ischemic cardiomyocyte injury.

Hypoxia related long non-coding RNAs in ischemic stroke

With high rates of mortality and disability, stroke has caused huge social burden, and 85% of which is ischemic stroke. In recent years, it is a progressive discovery of long non-coding RNA (lncRNA) playing an important regulatory role throughout ischemic stroke. Hypoxia, generated from reduction or interruption of cerebral blood flow, leads to changes in lncRNA expression, which then influence disease progression. Therefore, we reviewed studies on expression of hypoxia-related lncRNAs and relevant molecular mechanism in ischemic stroke. Considering that hypoxia-inducible factor (HIF) is a crucial regulator in hypoxic progress, we mainly focus on the HIF-related lncRNA which regulates the expression of HIF or is regulated by HIF, further reveal their pathogenesis and adaption after brain ischemia and hypoxia, so as to find effective biomarker and therapeutic targets.

Astragaloside IV attenuates hypoxia/reoxygenation injury-induced apoptosis of type II alveolar epithelial cells through miR-21-5p

We aimed to explore the role of miR-21-5p in the inhibitory effects of astragaloside IV (As-IV) on hypoxia/reoxygenation injury-induced apoptosis of type II alveolar epithelial cells. Rat type II alveolar epithelial cells RLE-6TN were cultured in vitro and randomly divided into control (C), hypoxia/reoxygenation injury (H/R), As-IV and miR-21-5p-siRNA + As-IV groups (n = 6). H/R model was established by 24 h of hypoxia and 4 h of reoxygenation. As-IV group was given 1 nmol/L As-IV and incubated for 1 h before modeling. MiR-21-5p-siRNA + As-IV group was transfected with 50 nmol/L miR-21-5p-siRNA. After 48 h, they were incubated with 1 nmol/L As-IV for 1 h before modeling. Cell viability was detected by cell counting kit-8 assay, and apoptosis rate was detected by flow cytometry. The expression levels of TLR4 and NF-κB were measured by immunofluorescence assay. The targeting relationship between miR-21-5p and TLR4 was determined by luciferase assay. Compared with H/R group, the cell viability, miR-21-5p, bax and cleaved caspase-3 expressions of As-IV group increased, apoptosis rate and Bcl-2 expression decreased, and TLR4 and NF-κB expressions were down-regulated (P < 0.05). Compared with As-IV group, the cell viability, miR-21-5p, bax and cleaved caspase-3 expressions of miR-21-5p-siRNA + As-IV group decreased, apoptosis rate and Bcl-2 expression increased, and the expressions of TLR4 and NF-κB were up-regulated (P < 0.05). As-IV up-regulates miR-21-5p expression, inhibits the TLR4/NF-κB signaling pathway and suppresses the apoptosis of type II alveolar epithelial cells during hypoxia/reoxygenation injury.

Remifentanil pretreatment ameliorates H/R-induced cardiac microvascular endothelial cell dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway

Restoration of blood supply through medical or surgical intervention is a commonly adopted method for acute myocardial ischemia, but is also a trigger for cardiac ischemia/reperfusion injury. Studies have shown that remifentanil (REM) displays cardioprotective effects. In this study, the effects of REM on HCMEC viability were examined before and after the induction of H/R using Cell Counting Kit-8 assays. Wound healing and Matrigel angiogenesis assays were performed to assess HCMEC migration and angiogenesis, respectively. Commercial kits and western blotting were used to determine the endothelial barrier function of H/R-stimulated HCMECs with or without REM treatment. The expression of PI3K/Akt/hypoxia-inducible factor-1α (HIF-1α) pathway-related proteins was detected by western blotting. After pre-treatment with PI3K/Akt, the effects of REM on H/R-induced HCMEC injury were examined. We found that pre-treatment with REM displayed no impact on HCMEC viability under normal conditions but noticeably improved cell viability following H/R. The migratory abilities and tube-like structure formations of H/R-stimulated HCMECs were both enhanced by REM in a concentration-dependent manner. REM also decreased the permeability of H/R-stimulated HCMECs and upregulated the expression of tight junction proteins. Furthermore REM increased the expression of PI3K/Akt/HIF-1α signaling-related proteins in HCMECs. Inhibition of PI3K/Akt rescued REM-enhanced HCMEC function under H/R condition. Therefore, the present study demonstrated that REM pretreatment ameliorated H/R-induced HCMEC dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway.

LncRNA SNHG15 relieves hyperglycemia-induced endothelial dysfunction via increased ubiquitination of thioredoxin-interacting protein

Numerous studies have revealed that hyperglycemia is a pivotal driver of diabetic vascular complications. However, the mechanisms of hyperglycemia-induced endothelial dysfunction in diabetes remain incompletely understood. This study aims to expound on the underlying mechanism of the endothelial dysfunction induced by hyperglycemia from the perspective of long non-coding RNAs (lncRNA). In this study, a downregulation of SNHG15 was observed in the ischemic hind limb of diabetic mice and high glucose (HG)-treated HUVECs. Functionally, the overexpression of SNHG15 promoted cell proliferation, migration, and tube formation, and suppressed cell apoptosis in HG-treated HUVECs. Mechanistically, SNHG15 reduced thioredoxin-interacting protein (TXNIP) expression by enhancing ITCH-mediated ubiquitination of TXNIP. TXNIP overexpression abrogated the protective effect of lncRNA SNHG15 overexpression on HG-induced endothelial dysfunction. The following experiment further confirmed that SNHG15 overexpression promoted angiogenesis of the ischemic hind limb in diabetic mice. In conclusion, SNHG15 is a novel protector for hyperglycemia-induced endothelial dysfunction via decreasing TXNIP expression.

LncRNA NORAD Promotes Vascular Endothelial Cell Injury and Atherosclerosis Through Suppressing VEGF Gene Transcription via Enhancing H3K9 Deacetylation by Recruiting HDAC6

Coronary artery disease (CAD) is a major atherosclerotic cardiovascular disease and the leading cause of mortality globally. Long non-coding RNAs (lncRNAs) play crucial roles in CAD development. To date, the effect of lncRNA non-coding RNA activated by DNA damage (NORAD) on atherosclerosis in CAD remains unclear. The primary aim of this study was to investigate the effect of lncRNA NORAD on vascular endothelial cell injury and atherosclerosis. Here, ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE^–/– mice were utilized as in vitro and in vivo models. The present study found that lncRNA NORAD expression was increased in ox-LDL-treated HUVECs and thoracic aorta of atherosclerotic mice, and knockdown of lncRNA NORAD alleviated vascular endothelial cell injury and atherosclerosis development in vitro and in vivo. Knockdown of lncRNA NORAD aggravated ox-LDL-reduced or atherosclerosis-decreased vascular endothelial growth factor (VEGF) expression in HUVECs and thoracic aorta of mice to ameliorate vascular endothelial cell injury and atherosclerosis development. Moreover, nucleus lncRNA NORAD suppressed VEGF gene transcription through enhancing H3K9 deacetylation via recruiting HDAC6 to the VEGF gene promoter in ox-LDL-treated HUVECs. In addition, VEGF reduced FUS (FUS RNA binding protein) expression by a negative feedback regulation in HUVECs. In summary, lncRNA NORAD enhanced vascular endothelial cell injury and atherosclerosis through suppressing VEGF gene transcription via enhancing H3K9 deacetylation by recruiting HDAC6. The findings could facilitate discovering novel diagnostic markers and therapeutic targets for CAD.

Differentially Expressed Circular Non-coding RNAs in Atherosclerotic Aortic Vessels and Their Potential Functions in Endothelial Injury

Background: Circular non-coding RNA (circRNA) has a variety of biological functions. However, the expression profile and potential effects of circRNA on atherosclerosis (AS) and vascular endothelial injury have not been fully elucidated. This study aims to identify the differentially expressed circRNAs in atherosclerotic aortic vessels and predict their potential functions in endothelial injury.

Method: ApoE-/- mice were fed with high-fat diet for 12 weeks to induce AS. Atherosclerotic plaques were evaluated by H&E and Masson staining and immunohistochemistry; differentially expressed circRNAs were detected by Arraystar Circular RNA Microarray and verified by RT-PCR; the potential target mircoRNAs of circRNAs were predicted by miRanda, Tarbase, Targetscan and their expression changes were verified by RT-PCR; the potential target genes of mircoRNAs were predicted by Targetscan and verified by Western blot; the signaling pathways that they might annotate or regulate and their potential functions in vascular endothelial injury were predicted by gene enrichment analysis.

Results: Fifty two circRNAs were up-regulated more than twice and 47 circRNAs were down-regulated more than 1.5 times in AS aortic vessels. Mmmu_circRNA_36781 and 37699 were up-regulated both in AS aortic vessels and H₂O₂-treated mouse aortic endothelial cells (MAECs). The expression of miR-30d-3p and miR-140-3p, the target microRNA of circRNA_37699 and circRNA_36781, were downregulated both in AS vessels and H₂O₂-treated MAECs. On the contrary, MKK6 and TP53RK, the potential target gene of miR-140-3p and miR-30d-3p, were upregulated both in AS aortic roots and H₂O₂-treated MAECs. Besides, gene enrichment analysis showed that MAPK and PI3K-AKT signaling pathway were the most potential signaling pathways regulated by the differentially expressed circRNAs in atherosclerosis.

Conclusions: Mmu_circRNA_36781 (circRNA ABCA1) and 37699 (circRNA KHDRBS1) were significantly up-regulated in AS aortic vessels and H₂O₂-treated MAECs. They have potential regulatory effects on atherosclerosis and vascular endothelial injury by targeting miR-30d-3p-TP53RK and miR-140-3p-MKK6 axis and their downstream signaling pathways.

Inhibition of lncRNA SNHG8 plays a protective role in hypoxia-ischemia-reoxygenation-induced myocardial injury by regulating miR-335 and RASA1 expression

Long non-coding (lnc)RNAs serve a role in a number of diseases, including different types of cancer and acute myocardial infarction. The aim of the present study was to investigate the protective role of lncRNA small nucleolar RNA host gene 8 (SNHG8) in hypoxia-ischemia-reoxygenation (HI/R)-induced myocardial injury and its potential mechanism of action. Cell viability, proliferation, creatine kinase myocardial band, cell apoptosis and protein expression levels were determined by Cell Counting Kit-8 assay, EdU assay, ELISA, flow cytometry and western blotting, respectively. The association between SNHG8 and microRNA (miR)-335 was confirmed using a dual-luciferase reporter gene assay. The effects of the miR-335 inhibitor transfections had on increasing apoptosis and decreasing H9C2 cell viability were reversed in cells co-transfected with SNHG8 small interfering (si)RNA. Furthermore, it was found that miR-335 could regulate RAS p21 protein activator 1 (RASA1) expression and that transfection with SNHG8 siRNA downregulated RASA1 expression. Silencing of RASA1 protected against HI/R-induced H9C2 cell injury. However, SNHG8 siRNA did not further reduce apoptosis, demonstrating that SNHG8 may act through RASA1, and RASA1 may mediate the protection of SNHG8 siRNA in HI/R myocardial injury. Thus, inhibition of lncRNA SNHG8 alleviated HI/R-induced myocardial damage by regulating miR-335 and RASA1.

MiR-518a-5p Targets GZMB to Extenuate Vascular Endothelial Cell Injury Induced by Hypoxia-Reoxygenation and Thereby Improves Myocardial Ischemia

To probe the function of miR-518a-5p/Granzyme B (GZMB) in hypoxia/reoxygenation (H/R) -induced vascular endothelial cell injury.The key genes of myocardial infarction were screened by bioinformatic methods. The upstream micro RNAs (miRNAs) of GZMB were predicted by TargetScan. The binding of miR-518a-5p to GZMB was verified with luciferase reporter assay. The H/R model was constructed with human vascular endothelial cell (HUVEC) in vitro. Cell Counting Kit-8 (CCK8) assay was performed to detect cell proliferation. Western blot was utilized to evaluate the levels of indicated proteins.GZMB was up-regulated in patients with myocardial infarction and identified as the key gene by the bioinformatics analysis. Then the prediction from TargetScan indicated that miR-518a-5p, which is down-regulated in myocardial infarction patients, might be the potential upstream miRNA for GZMB. The following experiments verified that miR-518a-5p could bind to the 3'UTR of GZMB and negatively modulates GZMB expression. More importantly, the miR-518a-5p mimic enhanced cell proliferation and repressed apoptosis of H/R-injured HUVEC cells by inhibiting GZMB expression.We proved that miR-518a-5p could partly attenuate H/R-induced HUVEC cell injury by targeting GZMB, and perhaps the miR-518a-5p/GZMB axis could be potential therapeutic targets for myocardial infarction.

Dysregulation of lncRNA SNHG1/miR-145 axis affects the biological function of human carotid artery smooth muscle cells as a mechanism of carotid artery restenosis

Carotid angioplasty and stenting have developed into reliable options for patients with carotid stenosis. However, postoperative restenosis remains a serious and unresolved problem. Restenosis is partly caused by the proliferation of vascular smooth muscle cells. As certain long non-coding RNAs (lncRNAs) affect cell proliferation and migration, the present study aimed to investigate them as novel biomarkers for restenosis development and to further reveal the potential underlying mechanisms. The expression of lncRNA small nucleolar RNA host gene 1 (SNHG1) and microRNA145 (miR-145) in human carotid artery smooth muscle cells (hHCtASMCs) was analyzed using reverse transcription-quantitative PCR. In addition, a luciferase reporter assay was performed to investigate the interaction between SNHG1 and miR-145. The effects of the SNHG1/miR-145 axis on the proliferation and migration of hHCtASMCs were evaluated by Cell Counting Kit-8 and Transwell assays. Serum SNHG1 and miR-145 expression levels were increased and decreased, respectively, in patients with restenosis (all P<0.001). High SNHG1 and low miR-145 were identified as risk factors for restenosis onset (all P<0.01). Furthermore, decreasing SNHG1 expression levels in hHCtASMCs inhibited cell proliferation and migration. The luciferase reporter assay and expression results demonstrated that miR-145 may be a target of SNHG1 and mediated the effects of SNHG1 on hHCtASMC proliferation and migration. The results obtained suggested that abnormal expression of SNHG1 and miR-145 may be risk factors for restenosis. The present study revealed that the SNHG1/miR-145 axis regulates hHCtASMC proliferation and migration, indicating its potential for restenosis prevention and treatment.

LncRNA SNHG15 relieves hyperglycemia-induced endothelial dysfunction via increasing ubiquitination of thioredoxin-interacting protein

OBJECTIVE

Numerous evidence indicates that hyperglycemia is a pivotal driver of the vascular complications of diabetes. However, the mechanisms of hyperglycemia-induced endothelial dysfunction in diabetes remain incompletely understood. This study aims to expound on the underlying mechanism of the endothelial dysfunction induced by hyperglycemia from the perspective of long non-coding RNAs (lncRNA).

MATERIALS AND METHODS

Cell proliferation, migration, apoptosis, and tube formation were measured by cell counting kit-8 assay, transwell assay, flow cytometry, and tube formation assay, respectively. RNA pull-down and RNA-binding protein immunoprecipitation were used to detect the interaction between lncRNA SNHG15 and thioredoxin-interacting protein (TXNIP). Co-immunoprecipitation was used to detect the ubiquitination level of TXNIP and the interaction between TXNIP and E3 ubiquitin ligase ITCH.

RESULTS

A downregulation of SNHG15 was observed in the ischemic hind limb of diabetic mice and high glucose (HG)-treated HUVECs. Functionally, the overexpression of SNHG15 promoted cell proliferation, migration, and tube formation, and suppressed cell apoptosis in HG-treated HUVECs. Mechanically, SNHG15 reduced TXNIP expression by enhancing ITCH-mediated ubiquitination of TXNIP. TXNIP overexpression abrogated the protective effect of LncRNA SNHG15 overexpression on HG-induced endothelial dysfunction. The following experiment further confirmed that SNHG15 overexpression promoted angiogenesis of the ischemic hind limb in diabetic mice.

CONCLUSION

SNHG15 is a novel protector for hyperglycemia-induced endothelial dysfunction via decreasing TXNIP expression.

Long Noncoding RNA/Circular RNA-miRNA-mRNA Axes in Ischemia-Reperfusion Injury

Ischemia-reperfusion injury (IRI) elicits tissue injury involved in a wide range of pathologies. Multiple studies have demonstrated that noncoding RNAs (ncRNAs), including long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs), participate in the pathological development of IRI, and they may act as biomarkers, therapeutic targets, or prognostic indicators. Nonetheless, the specific molecular mechanisms of ncRNAs in IRI have not been completely elucidated. Regulatory networks among lncRNAs/circRNAs, miRNAs, and mRNAs have been the focus of attention in recent years. Studies on the underlying molecular mechanisms have contributed to the discovery of therapeutic targets or strategies in IRI. In this review, we comprehensively summarize the current research on the lncRNA/circRNA-miRNA-mRNA axes and highlight the important role of these axes in IRI.

Downregulation of miR-140-3p Contributes to Upregulation of CD38 Protein in Bronchial Smooth Muscle Cells

In allergic bronchial asthma, an increased smooth muscle contractility of the airways is one of the causes of the airway hyperresponsiveness (AHR). Increasing evidence also suggests a possible involvement of microRNAs (miRNAs) in airway diseases, including asthma, although their roles in function and pathology largely unknown. The current study aimed to determine the role of a miRNA, miR-140-3p, in the control of protein expression of CD38, which is believed to regulate the contraction of smooth muscles, including the airways. In bronchial smooth muscles (BSMs) of the mice that were actively sensitized and repeatedly challenged with ovalbumin antigen, an upregulation of CD38 protein concurrently with a significant reduction of miR-140-3p was observed. In cultured human BSM cells (hBSMCs), transfection with a synthetic miR-140-3p inhibitor caused an increase in CD38 protein, indicating that its basal protein expression is regulated by endogenous miR-140-3p. Treatment of the hBSMCs with interleukin-13 (IL-13), an asthma-related cytokine, caused both an upregulation of CD38 protein and a downregulation of miR-140-3p. Transfection of the hBSMCs with miR-140-3p mimic inhibited the CD38 protein upregulation induced by IL-13. On the other hand, neither a CD38 product cyclic ADP-ribose (cADPR) nor its antagonist 8-bromo-cADPR had an effect on the BSM contraction even in the antigen-challenged mice. Taken together, the current findings suggest that the downregulation of miR-140-3p induced by IL-13 might cause an upregulation of CD38 protein in BSM cells of the disease, although functional and pathological roles of the upregulated CD38 are still unclear.

LncRNAs Stand as Potent Biomarkers and Therapeutic Targets for Stroke

Stroke is a major public health problem worldwide with a high burden of neurological disability and mortality. Long noncoding RNAs (lncRNAs) have attracted much attention in the past decades because of their newly discovered roles in pathophysiological processes in many diseases. The abundance of lncRNAs in the nervous system indicates that they may be part of a complex regulatory network governing physiology and pathology of the brain. In particular, lncRNAs have been shown to play pivotal roles in the pathogenesis of stroke. In this article, we provide a review of the multifaceted functions of lncRNAs in the pathogenesis of ischemic stroke and intracerebral hemorrhage, highlighting their promising use as stroke diagnostic biomarkers and therapeutics. To this end, we discuss the potential of stem cells in aiding lncRNA applications in stroke.

Downregulation of long noncoding RNA SNHG6 rescued propofol-induced cytotoxicity in human induced pluripotent stem cell-derived cardiomyocytes

Background

Propofol (PPF) overdose is a rare but lethal condition, which may lead to severe cardiac failure. In this study, we established an in vitro PPF-induced cardiac cytotoxicity model, and investigate the functional role of long non-coding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6).

Methods

Human induced pluripotent stem cell-derived cardiomyocytes (HiPSC-CMs) were exposed to PPF in vitro. PPF-induced cytotoxic effects were measured. PPF-induced SNHG6 expression change in HiPSC-CMs were monitored by qRT-PCR. SNHG6 was downregulated in HiPSC-CMs to examine its role in PPF-induced cardiac cytotoxicity. The expression of competing endogenous RNA (ceRNA) candidate of SNHG6, human microRNA-186-5p (hsa-miR-186-5p) was also investigated in PPF-exposed HiPSC-CMs. Functions of hsa-miR-186-5p were further investigated in PPF-exposed and SNHG6-downregulated HiPSC-CMs.

Results

PPF induced significant cytotoxicity, as well as SNHG6 upregulation in HiPSC-CMs. SNHG6 downregulation had rescuing effects on PPF-induced cardiac cytotoxicity. Dual-luciferase activity assay confirmed that hsa-miR-186-5p was the ceRNA candidate of SNHG6. QRT-PCR showed hsa-miR-186-5p expression was reversely correlated with SNHG6 in PPF-exposed HiPSC-CMs. Suppressing hsa-miR-186-5p reduced the rescuing effects of SNHG6-downregulation on PPF-induced cardiac cytotoxicity.

Conclusions

SNHG6/hsa-miR-186-5p can modulate PPF-induced cardiac cytotoxicity in HiPSC-CMs, and thus may be a future drug target to prevent PPF infusion syndrome.

FOXO3a-mediated long non-coding RNA LINC00261 resists cardiomyocyte hypoxia/reoxygenation injury via targeting miR23b-3p/NRF2 axis

Ischemia/reperfusion (I/R)‐mediated acute myocardial infarction (AMI) is a major pathological factor implicated in the progression of ischemic heart disease (IHD). Long non‐coding RNA plays an important role in regulating the occurrence and development of cardiovascular disease. The aim of this study was to investigate the regulating role of LINC00261 in hypoxia/reoxygenation (H/R)‐induced cardiomyocyte apoptosis. The relative expression of LINC00261, miR‐23b‐3p and NRF2 were determined in rats I/R myocardial tissues and H/R‐induced cardiomyocytes. The rat model and cell model of LINC00261 overexpression were established to investigate the biological function of LINC00261 on H9C2 cell. The interaction between LINC00261, miR‐23b‐3p, NRF2 and FOXO3a was identified using bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation (RIP) assay, chromatin immunoprecipitation (CHIP) assay and qRT‐PCR. The expression of LINC00261 was significantly down‐regulated in myocardial tissues and H9C2 cell. Overexpression of LINC00261 improves cardiac function and reduces myocardium apoptosis. Interestingly, transcription factor FOXO3a was found to promote LINC00261 transcription. Moreover, LINC00261 was confirmed as a spong of miR23b‐3p and thereby positively regulates NRF2 expression in cardiomyocytes. Our findings reveal a novel role for LINC00261 in regulating H/R cardiomyocyte apoptosis and the potency of the LINC00261/miR‐23b‐3p/NRF2 axis as a therapeutic target for the treatment of MIRI.

SNHG1 Inhibits ox-LDL-Induced Inflammatory Response and Apoptosis of HUVECs via Up-Regulating GNAI2 and PCBP1

Dysfunction of human endothelial cells is an important trigger for atherosclerosis. Oxidative low-density lipoprotein (ox-LDL) usually was used to stimulate the dysfunction of human umbilical vein endothelial cells (HUVECs). LncRNA SNHG1 (small nucleolar RNA host gene 1) is a cerebral infarction-associated gene. The present study was designed to investigate the role of SNHG1 in ox-LDL-induced HUVECs. Cell viability was evaluated by CCK-8 and MTT assay. Cell apoptosis was detected by flow cytometry analysis. Cell inflammatory response was evaluated by detecting LDH, IL-6, IL-1β levels. The results revealed that up-regulation of SNHG1 attenuated ox-LDL-induced cell injury and inflammatory response in HUVECs. Next, mechanism assays including RNA immunoprecipitation (RIP) assay, luciferase reporter assay, and RNA pull-down assay, helped us to identify the interaction between miR-556-5 and SNHG1. GNAI2 (G protein subunit alpha i2) and PCBP1 (poly(rC) binding protein 1) were identified as the downstream targets of miR-556-5p. SNHG1 regulated dysfunctions of ox-LDL-induced HUVECs via sponging miR-556-5p and up-regulating GNAI2 and PCBP1. SNHG1 attenuated cell injury and inflammatory response in ox-LDL-induced HUVECs via up-regulating both GNAI2 and PCBP1 at a miR-556-5p dependent way.

LncRNA SNHG1 promotes EMT process in gastric cancer cells through regulation of the miR-15b/DCLK1/Notch1 axis

Background

Gastric cancer (GC) is a malignant tumour originating from the gastric mucosa epithelium that seriously threatens human health. DCLK1, miR-15b and lncRNA SNHG1 play potential roles in the occurrence of GC, but the mechanism remains unclear.

Methods

Gene expression of DCLK1, miR-15b and lncRNA SNHG1 was investigated by qRT-PCR. Protein expression was detected by Western blotting. Migration and invasion of gastric cancer cells was tested by a Transwell assay and wound healing assay. Cell proliferation was measured by an MTT assay. Finally, the correctness of the prediction results was confirmed by a dual-luciferase reporter assay.

Results

The expression of DCLK1, Notch1, and SNHG1 was increased in GC tissues, while the expression of miR-15b was decreased. Overexpression of lncRNA SNHG1 promoted the expression of DCLK1 and Nothc1 in GC cells. Moreover, miR-15b targeted DCLK1 to regulate Notch1 expression and inhibited the EMT process in GC cells. SNHG1 enhanced the effects of DCLK1/Notch1 on the EMT process through regulating miR-15b expression.

Conclusion

SNHG1 enhances the EMT process in GC cells through DCLK1-mediated Notch1 pathway, which can be a potential target for treating GC.

Pathological Roles of Mitochondrial Oxidative Stress and Mitochondrial Dynamics in Cardiac Microvascular Ischemia/Reperfusion Injury

Mitochondria are key regulators of cell fate through controlling ATP generation and releasing pro-apoptotic factors. Cardiac ischemia/reperfusion (I/R) injury to the coronary microcirculation has manifestations ranging in severity from reversible edema to interstitial hemorrhage. A number of mechanisms have been proposed to explain the cardiac microvascular I/R injury including edema, impaired vasomotion, coronary microembolization, and capillary destruction. In contrast to their role in cell types with higher energy demands, mitochondria in endothelial cells primarily function in signaling cellular responses to environmental cues. It is clear that abnormal mitochondrial signatures, including mitochondrial oxidative stress, mitochondrial fission, mitochondrial fusion, and mitophagy, play a substantial role in endothelial cell function. While the pathogenic role of each of these mitochondrial alterations in the endothelial cells I/R injury remains complex, profiling of mitochondrial oxidative stress and mitochondrial dynamics in endothelial cell dysfunction may offer promising potential targets in the search for novel diagnostics and therapeutics in cardiac microvascular I/R injury. The objective of this review is to discuss the role of mitochondrial oxidative stress on cardiac microvascular endothelial cells dysfunction. Mitochondrial dynamics, including mitochondrial fission and fusion, are critically discussed to understand their roles in endothelial cell survival. Finally, mitophagy, as a degradative mechanism for damaged mitochondria, is summarized to figure out its contribution to the progression of microvascular I/R injury.

Association of Nuclear Receptor Coactivators with Hypoxia-Inducible Factor-1α in the Serum of Patients with Chronic Kidney Disease

Nuclear receptor coactivators (NCOAs), consisting of coactivators and corepressors, dramatically enhance the transcriptional activity of nuclear receptors. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that plays a major role under hypoxic conditions. This study was performed with the focus on the association of NCOAs with HIF-1α in the serum of chronic kidney disease (CKD) patients. Sixty patients with stage 5 CKD and 30 healthy controls from The Second Affiliated Hospital of Shantou University Medical College, between March 21, 2019, and October 30, 2019, were recruited in this prospective cohort study. We analyzed the serum levels of NCOAs (NCOA1, NCOA2, and NCOA3), HIF-1α, vascular endothelial growth factor (VEGF), etc. and assessed whether there was any relationship between these parameters and CKD disease. We found that circulating NCOA1 was positively associated with circulating NCOA2, NCOA3, and HIF-1α. A positive correlation was also observed between NCOA2 and NCOA1, NCOA3, HIF-1α, and VEGF. Furthermore, statistically significant correlations between NCOA3 and NCOA1, NCOA2, and HIF-1α were observed. The serum levels of VEGF in the CKD group were higher than those of the healthy control group. Circulating NCOA1 and circulating NCOA2 were negatively associated with procalcitonin. In conclusion, there was an association between circulating NCOA1, NCOA2, NCOA3, and circulating HIF-1α, and circulating VEGF was a risk factor for CKD disease. However, more studies should be performed to confirm this hypothesis.