lncRNA-SNHG14 Plays a Role in Acute Lung Injury Induced by Lipopolysaccharide through Regulating Autophagy via miR-223-3p/Foxo3a

circCUL3 drives malignant progression of cervical cancer by activating autophagy through sponge miR-223-3p upregulation of ATG7

Circular RNA (circRNA) has emerged as a pivotal regulatory factor in cancer biology, yet its exact role in cervical cancer remains incompletely understood. In this study, we investigated the functional role of circCUL3 in cervical cancer and explored its potential as a therapeutic target. Functional gain and loss experiments were conducted in Hela and Siha cell lines to elucidate the biological functions of circCUL3 in cervical cancer. The results revealed that circCUL3 overexpression significantly enhanced cell viability, migration, and invasion while suppressing apoptosis, while circCUL3 knockout displayed the opposite effects. Mechanistically, we identified hsa-miR-223-3p as a target of circCUL3, with its expression being negatively regulated by circCUL3. Furthermore, we discovered that circCUL3 could sequester miR-223-3p, leading to the upregulation of ATG7 expression, and this was linked to the regulation of autophagy in cervical cancer cells. In vivo validation using a xenograft mouse model further supported our in vitro findings. Notably, we found that chloroquine (CQ), an autophagy inhibitor, restored miR-223-3p expression and counteracted the oncogenic effect of circCUL3 overexpression. In conclusion, circCUL3 potentially contributes to the malignant progression of cervical cancer by acting as a sponge for miR-223-3p, resulting in the upregulation of ATG7 and the activation of autophagy.

Novel Therapeutic Target for ALI/ARDS: Forkhead Box Transcription Factors

ALI/ARDS can be a pulmonary manifestation of a systemic inflammatory response or a result of overexpression of the body's normal inflammatory response involving various effector cells, cytokines, and inflammatory mediators, which regulate the body's immune response through different signalling pathways. Forkhead box transcription factors are evolutionarily conserved transcription factors that play a crucial role in various cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism, and DNA damage response. Transcription factors control protein synthesis by regulating gene transcription levels, resulting in diverse biological outcomes. The Fox family plays a role in activating or inhibiting the expression of various molecules related to ALI/ARDS through phosphorylation, acetylation/deacetylation, and control of multiple signalling pathways. An in-depth analysis of the integrated Fox family's role in ALI/ARDS can aid in the development of potential diagnostic and therapeutic targets for the condition.

LL37-mtDNA regulates viability, apoptosis, inflammation, and autophagy in lipopolysaccharide-treated RLE-6TN cells by targeting Hsp90aa1

Sepsis-induced acute lung injury is associated with lung epithelial cell injury. This study analyzed the role of the antimicrobial peptide LL37 with mitochondrial DNA (LL37-mtDNA) and its potential mechanism of action in lipopolysaccharide (LPS)-treated rat type II alveolar epithelial cells (RLE-6TN cells). RLE-6TN cells were treated with LPS alone or with LL37-mtDNA, followed by transcriptome sequencing. Differentially expressed and pivotal genes were screened using bioinformatics tools. The effects of LL37-mtDNA on cell viability, inflammation, apoptosis, reactive oxygen species (ROS) production, and autophagy-related hallmark expression were evaluated in LPS-treated RLE-6TN cells. Additionally, the effects of Hsp90aa1 silencing following LL37-mtDNA treatment were investigated in vitro. LL37-mtDNA further suppressed cell viability, augmented apoptosis, promoted the release of inflammatory cytokines, increased ROS production, and elevated LC3B expression in LPS-treated RLE-6TN cells. Using transcriptome sequencing and bioinformatics, ten candidate genes were identified, of which three core genes were verified to be upregulated in the LPS + LL37-mtDNA group. Additionally, Hsp90aa1 downregulation attenuated the effects of LL37-mtDNA on LPS-treated RLE-6TN cells. Hsp90aa1 silencing possibly acted as a crucial target to counteract the effects of LL37-mtDNA on viability, apoptosis, inflammation, and autophagy activation in LPS-treated RLE-6TN cells.

Role and mechanisms of autophagy, ferroptosis, and pyroptosis in sepsis-induced acute lung injury

Sepsis-induced acute lung injury (ALI) is a major cause of death among patients with sepsis in intensive care units. By analyzing a model of sepsis-induced ALI using lipopolysaccharide (LPS) and cecal ligation and puncture (CLP), treatment methods and strategies to protect against ALI were discussed, which could provide an experimental basis for the clinical treatment of sepsis-induced ALI. Recent studies have found that an imbalance in autophagy, ferroptosis, and pyroptosis is a key mechanism that triggers sepsis-induced ALI, and regulating these death mechanisms can improve lung injuries caused by LPS or CLP. This article summarized and reviewed the mechanisms and regulatory networks of autophagy, ferroptosis, and pyroptosis and their important roles in the process of LPS/CLP-induced ALI in sepsis, discusses the possible targeted drugs of the above mechanisms and their effects, describes their dilemma and prospects, and provides new perspectives for the future treatment of sepsis-induced ALI.

KLF13 Attenuates Lipopolysaccharide-Induced Alveolar Epithelial Cell Damage by Regulating Mitochondrial Quality Control via Binding PGC-1α

Sepsis is a clinically life-threatening syndrome, and acute lung injury is the earliest and most serious complication. We aimed to assess the role of kruppel-like factor 13 (KLF13) in lipopolysaccharide (LPS)-induced human alveolar type II epithelial cell damage and to reveal the possible mechanism related to peroxisome proliferator-activated receptor-γ co-activator 1-α (PGC-1α). In LPS-treated A549 cells with or without KLF13 overexpression or PGC-1α knockdown, cell viability was measured by a cell counting kit-8 assay. Enzyme-linked immunosorbent assay kits detected the levels of inflammatory factors, and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining measured cell apoptosis. Besides, mitochondrial reactive oxygen species (MitoSOX) and mitochondrial membrane potential were detected using MitoSOX red- and JC-1 staining. Expression of proteins related to mitochondrial quality control (MQC) was evaluated by western blot. Co-immunoprecipitation (Co-IP) assay was used to analyze the interaction between KLF13 and PGC-1α. Results indicated that KLF13 was highly expressed in LPS-treated A549 cells. KLF13 upregulation elevated the viability and reduced the levels of inflammatory factors in A549 cells exposed to LPS. Moreover, KLF13 gain-of-function inhibited LPS-induced apoptosis of A549 cells, accompanied by upregulated BCL2 expression and downregulated Bax and cleaved caspase3 expression. Furthermore, MQC was improved by KLF13 overexpression, as evidenced by decreased MitoSOX, JC-1 monomers and increased JC-1 aggregates, coupled with the changes of proteins related to MQC. In addition, Co-IP assay confirmed the interaction between KLF13 and PGC-1α. PGC-1α deficiency restored the impacts of KLF13 upregulation on the inflammation, apoptosis, and MQC in LPS-treated A549 cells. In conclusion, KLF13 attenuated LPS-induced alveolar epithelial cell inflammation and apoptosis by regulating MQC via binding PGC-1α.

Predictive value of miR-7110-5p and miR-223-3p as biomarkers for sepsis secondary to pneumonia

BACKGROUND

Investigating the secondary sepsis of pneumonia is of great significance for rapid diagnosis and early treatment of sepsis.

OBJECTIVE

This study aimed to investigate the predictive value of micro ribonucleic acids (miRNA) 7110-5p and miR-223-3p in sepsis secondary to pneumonia. A miRNA microarray was used to analyze the differences in miRNA expression between patients with pneumonia and those with sepsis secondary to pneumonia.

METHODS

The study included a total of 50 patients with pneumonia and 42 patients with sepsis secondary to pneumonia. Quantitative polymerase chain reaction analysis was conducted to measure the circulating miRNA expression levels in patients and assess their correlations with clinical characteristics and prognosis. In this study, nine miRNAs - hsa-miR-4689-5p, hsa-miR-4621-5p, hsa-miR-6740-5p, hsa-miR-7110-5p, hsa-miR-765, hsa-miR-940, hsa-miR-213-5p, hsa-miR-223-3p, and hsa-miR-122 - met the screening criteria of having a fold change ⩾ 2 or < 0.5; p< 0.01 indicated significant differences in the results.

RESULTS

The expression levels of miR-7110-5p and miR-223-3p differed between the two patient groups, being up-regulated in the plasma of patients with sepsis secondary to pneumonia. miR-7110-5p and miR-223-3p showed higher expression levels in both patients with pneumonia and sepsis compared to healthy controls. Moreover, the receiver operating characteristic curve revealed that the areas under the curve for predicting pneumonia using miR-7110-5p were 0.781 while those for predicting sepsis secondary to pneumonia were 0.862. For miR-223-3p, the corresponding values for predicting pneumonia and sepsis secondary to pneumonia were 0.879 and 0.924, respectively. However, there were no significant differences in the levels of miR-7110-5p and miR-223-3p between the plasma of survived and deceased patients with sepsis.

CONCLUSIONS

MiR-7110-5p and miR-223-3p have the potential to serve as biological indicators for predicting sepsis secondary to pneumonia.

FTO attenuates LPS-induced acute kidney injury by inhibiting autophagy via regulating SNHG14/miR-373-3p/ATG7 axis

N6-methyladenosine (m6A) is a master driver of RNA function and implicates in the pathogenesis of renal injury. LncRNA SNHG14 is highly expressed in sepsis patients with acute kidney injury (AKI) and aggravates kidney cell dysfunction. This study aimed to explore whether demethylase FTO affect m6A methylation of SNHG14 in AKI injury and its underlying mechanism. The expression level of FTO was obviously downregulated in sepsis-associated AKI patients compared with normal controls. Mechanistically, FTO overexpression impeded SNHG14 expression by decreasing the stability of SNHG14 in an m6A-dependent manner in LPS-induced HK-2 cells. Additionally, FTO overexpression inhibited cell autophagy and apoptosis while promoting cell viability of LPS-induced HK-2 cells. Moreover, overexpression of FTO inhibited SNHG14 expression and autophagy in LPS-induced AKI mice. Functionally, SNHG14 acts as a competing endogenous RNA (ceRNA) via directly sponging miR-373-3p in LPS induced HK-2 cells. Additionally, miR-373-3p directly targets ATG7. Inhibition of SNHG14 suppresses NF-κB signaling pathway and production of inflammatory cytokines (TNF-α, IL-6, and IL-1β) via miR-373-3p/ATG7 in LPS-induced HK-2 cells. Furthermore, the SNHG14/miR-373-3p/ATG7 interaction network contributes to the regulatory effect of FTO on LPS-induced HK-2 cell viability, apoptosis and autophagy. These results suggested demethylase FTO suppressed the m6A modification of lncRNA SNHG14 and inhibits autophagy in LPS-induced AKI via regulating miR-373-3p/ATG7, which provided an important novel perspective for understanding sepsis-associated AKI and is conducive for developing new therapeutic targets and strategies.

LncRNA LBX2-AS1 promotes proliferation and migratory capacity of clear cell renal cell carcinoma through mitophagy

BACKGROUND

Long non-coding RNAs (lncRNAs) have been extensively investigated in the field of cancer, among which, lncRNA ladybird homeobox 2-antisense RNA 1 (LBX2-AS1) has been demonstrated to exert carcinogenic effects on a variety of malignancies. However, the biological functions of LBX2-AS1 in clear cell renal cell carcinoma (ccRCC) have not been explicitly elucidated.

METHODS

Arraystar lncRNA chip and qRT-PCR verify the expression of LncRNA LBX2-AS1 in ccRCC. CCK-8 assay and cell cloning assay were used to assess the proliferative capacity of ccRCC cells. Migration abilities were quantified by scratch assay and transwell assay. Potential molecular signaling pathways were determined by high-throughput whole transcriptomics analysis. WB analysis was performed to validate the relationship between LBX2-AS1 and key molecules of mitophagy pathway. The effect of LBX2-AS1 on mitophagy was observed by laser confocal microscopy. Rescue experiments further validated the role of downstream gene FOXO3A in the LBX2-AS1 signaling pathway. Finally, the authentic effect of LBX2-AS1 was verified in vivo.

RESULTS

LncRNA LBX2-AS1 was over expressed in ccRCC tissues and could enhance the proliferation and migration of ccRCC cells. Autophagic pathway was identified as a possible mechanism involved in the oncogenic effect of LBX2-AS1. Mitophagy levels were observed in LBX2-AS1 low-expressing cells through laser confocal microscopy. Knockdown of LBX2-AS1 significantly elevated mitophagy levels as observed using laser confocal microscopy and led to FOXOA3 decreasing in and BNIP3L and LC3 enrichment. Meanwhile, LBX2-AS1 knocking down dampened the proliferation of ccRCC cells in vivo.

Study on identification of a three-microRNA panel in serum for diagnosing neonatal early onset sepsis

BACKGROUND

Comparing with other diseases, early onset sepsis (EOS) is a global health concern in neonatal period for its high morbidity and mortality rates. In recent years, many studies have contributed to the figure out the expression patterns of circulating micro-RNAs (miRNAs) in different diseases and progressions, which could function as diagnostic biomarkers for EOS. The purpose of this study was to analyze the expression patterns of selected miRNAs and evaluate their diagnostic value for early detection and treatment.

METHODS

This was a prospective cross-sectional study conducted from 1 July 2021 to 30 June 2022. We collected surplus peripheral blood and demographic statistics of septic neonates and non-infected neonates during the first 24 h after delivery and obtained 11 candidate miRNAs by literature screening. First, we extracted the candidate miRNAs from the serum of selected neonates and analyzed their expression levels, and then the receiver operating characteristic (ROC) curve was used to select the differentially expressed miRNAs. We analyzed their sensitivity and specificity and obtained the best diagnostic panel. Finally, with the help of differentially expressed miRNAs, we performed gene ontology (GO) enrichment and protein-protein interaction (PPI) analyses by their target genes.

RESULTS

In patients with EOS, three miRNAs (mir-223-3p, mir-15a-5p, and mir-17-5p) in serum were significantly downregulated, and mir-146a-5p, mir-1-3p, and mir-16-5p were upregulated. The diagnostic value of these miRNAs (miR-15a-5p, AUC = 0.67; miR-223-3p, AUC = 0.72; miR-16-5p, AUC = 0.68; miR-17-5p, AUC = 0.70; miR-1-3p, AUC = 0.69; miR-146a-5p, AUC = 0.72) was moderate, and the diagnostic panel constructed by miR-15a-5p, miR-223-3p, and miR-16-5p possessed a comparatively higher diagnostic value (AUC = 0.85, sensitivity: 74.6%, specificity: 86%), indicating that their combined application may be a promising biomarker for clinical diagnosis of EOS. According to GO enrichment analysis, most proteins encoded by target genes were located in the cytosol as for cellular component (CC), for molecular function (MF), most proteins acted as regulators in protein binding, and for biological process (BP). Most genes function in positive or negative regulation of transcription from RNA polymerase II promoter, and the top 10 hub genes were CDKN1A, YAP1, CCNE1, CCND1, CKK6, ERBB4, CHEK1, DICER1, VEGFA, and APP by rank degree after PPI construction.

CONCLUSIONS

The three-miRNA panels (miR-15a-5p, miR-223-3p, and miR-16-5p) may be a novel noninvasive biological marker for EOS screening.

Hypoxic bone marrow mesenchymal stem cell-derived exosomal lncRNA XIST attenuates lipopolysaccharide-induced acute lung injury via the miR-455-3p/Claudin-4 axis

Mesenchymal stem cell-derived exosomes and long non-coding RNAs (lncRNAs) have been identified to play a role in acute lung injury (ALI). In this study, we investigated whether exosomal lncRNAs could regulate ALI and the underlying mechanisms. Bone marrow mesenchymal stem cells (BM-MSCs) were pretreated with hypoxia or normoxia, and exosomes were subsequently extracted from normoxic BM-MSCs (Nor-exos) and hypoxic BM-MSCs (Hypo-exos). A rat model of ALI was established via an airway perfusion of lipopolysaccharide (LPS). Exosomes were administered via the tail vein to evaluate the in vivo effect of exosomes in ALI. LPS-exposed RLE-6TN cells were incubated with exosomes to explore their in vitro effect in ALI. A luciferase reporter assay was used to evaluate the interaction between lncRNA XIST and miR-455-3p, as well as miR-455-3p and Claudin-4. We found that the exosomes attenuated LPS-induced ALI and Hypo-Exos exerted a greater therapeutic effect compared with Nor-exos both in vitro and in vivo. Moreover, an abundance of lncRNA XIST was observed in Hypo-exos compared with Nor-exos. Mechanistically, LncRNA XIST functioned as a miR-455-3p sponge and targeted Claudin-4 in ALI. Our results provide novel insight into the role of exosomal lncRNA XIST for the treatment of ALI. Thus, hypoxic pretreatment may represent an effective method for improving the therapeutic effects of exosomes.

LncRNA SNHG14 activates autophagy via regulating miR-493-5p/Mef2c axis to alleviate osteoporosis progression

Osteoporosis is a progressive bone disease caused by impaired function of endogenous bone marrow-derived mesenchymal stem cells (BMSCs). Herein, we investigated the mechanism of lncRNA SNHG14 in osteoporosis progression. BMSCs were isolated from BALB/c mice. The osteogenic ability of BMSCs was assessed by Alkaline phosphatase (ALP) and Alizarin Red S Staining (ARS) staining. The interaction between miR-493-5p and SNHG14 or myocyte enhancer factor 2 C (Mef2c) was confirmed by dual-luciferase reporter assay. Bone histomorphometry changes were evaluated to analyze SNHG14'roles in osteoporosis in vivo. Our results illustrated SNHG14 and Mef2c levels were increased in a time-dependent manner in BMSCs, and miR-493-5p expression was decreased. SNHG14 knockdown inhibited osteogenic differentiation of BMSCs, and SNHG14 upregulation had the opposite effect. SNHG14 overexpression elevated bone mineral density and bone trabecular number, and alleviated osteoporosis progression in vivo. Mechanically, miR-493-5p was a target of SNHG14, and miR-493-5p targeted the Mef2c gene directly. SNHG14 overexpression reversed the inhibition of miR-493-5p on the osteogenic ability of BMSCs, and miR-493-5p silencing accelerated BMSCs osteogenesis by activating Mef2c-mediated autophagy to accelerate BMSCs osteogenesis. In short, SNHG14 activated autophagy via regulating miR-493-5p/Mef2c axis to alleviate osteoporosis progression, which might provide a new molecular target for osteoporosis treatment.

Autophagy in sepsis-induced acute lung injury: Friend or foe?

Sepsis-induced acute lung injury (ALI) is a life-threatening syndrome with high mortality and morbidity, resulting in a heavy burden on family and society. As a key factor that maintains cellular homeostasis, autophagy is regarded as a self-digesting process by which damaged organelles and useless proteins are recycled for cell metabolism, and it thus plays a crucial role during physiological and pathological processes. Recent studies have indicated that autophagy is involved in the pathophysiological process of sepsis-induced ALI, including cell apoptosis, inflammation, and mitochondrial dysfunction, which indicates that regulating autophagy may be beneficial for this disease. However, the role of autophagy in the etiology and treatment of sepsis-induced ALI is not well characterized. This review summarizes the autophagy-related signaling pathways in sepsis-induced ALI, as well as focuses on the dual role of autophagy and its regulation by non-coding RNAs during disease progression, for the development of potential therapeutic strategies in this disease.

Long Non-Coding RNA Dancr Affects Myocardial Fibrosis in Atrial Fibrillation Mice via the MicroRNA-146b-5p/Smad5 Axis

Objectives

Atrial fibrillation (AF) is the most frequent arrhythmia, and myocardial fibrosis (MF) has a close association with atrial remodeling and leads to AF. This study aimed to explore the function of the long non-coding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (Dancr)/microRNA (miR)-146b-5p/Smad5 axis on MF in AF mice.

Methods

AF mouse models were established. Overexpression Dancr lentivirus was injected into AF mice to increase Dancr expression in myocardial tissues. LncRNA Dancr, miR-146b-5p, and Smad5 expression levels and inflammatory factors (IL-18 and TNF-α) in the myocardial tissues were measured. MF was measured and the expression levels of MF-related genes (COL1A1, α-SMA, and FN1) were detected. In addition, in vitro HL-1 cell rapid pacing models were constructed, and after lncRNA Dancr and miR-146b-5p-related construct transfection, cell viability and cell apoptosis were determined.

Results

LncRNA Dancr up-regulation ameliorated MF in the AF mice, reduced IL-18 and TNF-α expression levels in myocardial tissues, and decreased COL1A1, α-SMA, and FN1 expression levels. The in vitro HL-1 cell rapid pacing models suggested that miR-146b-5p overexpression reversed the inhibitory effects of lncRNA Dancr overexpression on MF in HL-1 cells, and Smad5 interference reversed the ameliorative effects of miR-146b-5p interference on MF in HL-1 cells.

Conclusions

LncRNA Dancr can sponge miR-146b-5p to promote Smad5 expression, thereby delaying MF in AF mice.

SIRT3 alleviates sepsis-induced acute lung injury by inhibiting pyroptosis via regulating the deacetylation of FoxO3a

OBJECTIVE

This study mainly analyzes the mechanism of SIRT3 alleviating sepsis-induced acute lung injury (ALI) by regulating the deacetylation of FoxO3a and inhibiting pyroptosis.

METHODS

SIRT3-overexpressing and silenced BEAS-2B cells were used to evaluate the effect of SIRT3 on apoptosis in LPS-treated lung epithelial cells. FoxO3a-silenced BEAS-2B cells were also used to verify the mechanism by which SIRT3 inhibited oxidative stress and pyroptosis in vitro in ALI. 3-TYP was used to inhibit the deacetylation function of SIRT3 in vivo. Pyroptosis was assessed by detecting GSDMD-N and LDH efflux.

RESULTS

In CLP-induced ALI mice, GSDMD-N and LDH levels were elevated, pyroptosis was induced. Silencing of SIRT3 exacerbated oxidative stress, NLRP3 activation and pyroptosis, and inhibited the deacetylation of FoxO3a. Overexpression of SIRT3 attenuated pyroptosis, induced deacetylation and restored the expression of FoxO3a and MnSOD. Silencing FoxO3a aggravated pyroptosis. Overexpression of SIRT3 restored the reduced FoxO3a expression and suppressed pyroptosis. 3-TYP blocked the promotion of FoxO3a by SIRT3 and the inhibitory effect of SIRT3 on pyroptosis.

CONCLUSION

The reduction of SIRT3 in sepsis caused hyperacetylation of FoxO3a, which in turn exacerbates oxidative stress and induces pyroptosis of ALI. Increasing the level of SIRT3 promotes FoxO3a through deacetylation, thereby inhibiting pyroptosis and relieving ALI.

LncRNA CDKN2B-AS1 interacts with LIN28B to exacerbate sepsis-induced acute lung injury by inducing HIF-1α/NLRP3-mediated pyroptosis

Sepsis-associated acute lung injury (ALI) is a life-threatening condition in intensive care units with high mortality. LncRNAs have been confirmed to participate in the underlying pathogenesis of septic ALI. This study investigated the biological functions of lncRNA CDKN2B-AS1 in septic ALI and its potential mechanism.BEAS-2B cells were challenged with lipopolysaccharide (LPS) and mice were subjected to caecal ligation and puncture (CLP) to induce septic ALI in vitro and in vivo. The expression levels of CDKN2B-AS1, LIN28B, HIF-1α, and pyroptosis-related molecules were assessed by qRT-PCR or Western blotting. The production of IL-1β and IL-18 was detected by ELISA. BEAS-2B cell pyroptosis was examined by flow cytometry. The interaction between LIN28B and CDKN2B-AS1/HIF-1α was validated by RIP and RNA pull-down assays. Colocalization of CDKN2B-AS1 and LIN28B was observed by FISH. ALI was determined by HE staining, the lung wet-to-dry (W/D) weight ratio, inflammatory cell numbers, and total protein concentration in bronchoalveolar lavage fluid (BALF). Caspase-1 expression in the lung tissues was examined by immunohistochemical staining.CDKN2B-AS1 was upregulated in BEAS-2B cells after LPS stimulation. CDKN2B-AS1 knockdown inhibited pyroptosis in LPS-exposed BEAS-2B cells in vitro and the lung tissues of septic mice in vivo. Mechanistically, CDKN2B-AS1 interacted with LIN28B to enhance HIF-1α stability. Rescue experiments showed that HIF-1α overexpression counteracted the inhibitory effect of sh-CDKN2B-AS1 on LPS-induced pyroptosis. CDKN2B-AS1 bound to LIN28B to trigger NLRP3-mediated pyroptosis by stabilizing HIF-1α, which promoted sepsis-induced ALI. CDKN2B-AS1 might be a novel therapeutic target for this disease.

Long noncoding RNA MALAT1 inhibition attenuates sepsis-induced acute lung injury through modulating the miR-129-5p/PAX6/ZEB2 axis

This research aimed to investigate the role of the long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/microRNA-129-5p (miR-129-5p)/paired box gene 6 (PAX6) axis in sepsis-induced acute lung injury (ALI). MLE-12 cells and C57BL/6 mice were induced by LPS to establish lung injury in in vitro and in vivo models. Cell viability and apoptosis were measured by cell counting kit-8 assay and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) staining, respectively. Levels of inflammatory cytokines in cell supernatants and bronchoalveolar lavage fluid (BALF) were detected by ELISA. Lung injury was evaluated by lung wet weight-to-dry weight ratio and hematoxylin-eosin staining. MALAT1, PAX6, and zinc finger E-box-binding homeobox 2 (ZEB2) expression was elevated and miR-129-5p expression was reduced in the serum of patients with sepsis-induced ALI, LPS-induced MLE-12 cells, and lung tissues of ALI mice. MALAT1 interference delayed the LPS-induced cell proliferation decrease, apoptosis increase, and inflammatory factor increase. miR-129-5p inhibition could reverse the delaying effect of MALAT1 interference on LPS-induced lung cell injury. PAX6 overexpression (oe) reversed the inhibitory effect of miR-129-5p oe on LPS-induced lung cell injury. Downregulating MALAT1 reduced pulmonary edema, inflammatory cytokine levels, lung injury, and apoptosis in ALI mice. Moreover, miR-129-5p suppression or PAX6 oe reversed the delaying effect of MALAT1 interference on sepsis-induced ALI. MALAT1 aggravates sepsis-induced ALI via the miR-129-5p/PAX6/ZEB2 axis.

A systematic review of the research progress of non-coding RNA in neuroinflammation and immune regulation in cerebral infarction/ischemia-reperfusion injury

Cerebral infarction/ischemia-reperfusion injury is currently the disease with the highest mortality and disability rate of cardiovascular disease. Current studies have shown that nerve cells die of ischemia several hours after ischemic stroke, which activates the innate immune response in the brain, promotes the production of neurotoxic substances such as inflammatory cytokines, chemokines, reactive oxygen species and − nitrogen oxide, and mediates the destruction of blood-brain barrier and the occurrence of a series of inflammatory cascade reactions. Meanwhile, the expression of adhesion molecules in cerebral vascular endothelial cells increased, and immune inflammatory cells such as polymorphonuclear neutrophils, lymphocytes and mononuclear macrophages passed through vascular endothelial cells and entered the brain tissue. These cells recognize antigens exposed by the central nervous system in the brain, activate adaptive immune responses, and further mediate secondary neuronal damage, aggravating neurological deficits. In order to reduce the above-mentioned damage, the body induces peripheral immunosuppressive responses through negative feedback, which increases the incidence of post-stroke infection. This process is accompanied by changes in the immune status of the ischemic brain tissue in local and systemic systems. A growing number of studies implicate noncoding RNAs (ncRNAs) as novel epigenetic regulatory elements in the dysfunction of various cell subsets in the neurovascular unit after cerebral infarction/ischemia-reperfusion injury. In particular, recent studies have revealed advances in ncRNA biology that greatly expand the understanding of epigenetic regulation of immune responses and inflammation after cerebral infarction/ischemia-reperfusion injury. Identification of aberrant expression patterns and associated biological effects of ncRNAs in patients revealed their potential as novel biomarkers and therapeutic targets for cerebral infarction/ischemia-reperfusion injury. Therefore, this review systematically presents recent studies on the involvement of ncRNAs in cerebral infarction/ischemia-reperfusion injury and neuroimmune inflammatory cascades, and elucidates the functions and mechanisms of cerebral infarction/ischemia-reperfusion-related ncRNAs, providing new opportunities for the discovery of disease biomarkers and targeted therapy. Furthermore, this review introduces clustered regularly interspaced short palindromic repeats (CRISPR)-Display as a possible transformative tool for studying lncRNAs. In the future, ncRNA is expected to be used as a target for diagnosing cerebral infarction/ischemia-reperfusion injury, judging its prognosis and treatment, thereby significantly improving the prognosis of patients.

MiR-223-3p-loaded exosomes from bronchoalveolar lavage fluid promote alveolar macrophage autophagy and reduce acute lung injury by inhibiting the expression of STK39

This study investigated the molecular mechanism by which bronchoalveolar lavage fluid exosomes (BALF-exo) alleviated acute lung injury (ALI). BALF-exo was isolated from mice. LPS was used to induce inflammation in rat alveolar macrophages (NR8383). NR8383 cell models were treated with BALF-exo or BALF-exo loaded with miR-223-3p mimics/inhibitors, or STK39 was overexpressed in NR8383 cells before LPS and BALF-exo treatment. These cells were subjected to apoptosis, autophagy, and inflammation assays. RNA immunoprecipitation and dual-luciferase reporter assay were conducted to verify the binding between miR-223-3p and STK39. LPS-induced ALI mouse models were treated with BALF-exo loaded with miR-223-3p mimics. miR-223-3p was lowly expressed in BALF-exo from LPS-treated mice. BALF-exo loaded with miR-223-3p mimics increased viability and autophagy and decreased apoptosis and inflammation in NR8383 cell models. Inhibition of miR-223-3p in BALF-exo or overexpression of STK39 in NR8383 cells repressed the therapeutic effect of BALF-exo in LPS-treated NR8383 cells. STK39 was a target gene of miR-223-3p. miR-223-3p shuttled by BALF-exo negatively regulated the expression of STK39 in NR8383 cells. BALF-exo loaded with miR-223-3p mimics also reduced lung injuries in ALI mice. In conclusion, miR-223-3p loaded in BALF-exo alleviates ALI by targeting STK39 in alveolar macrophages.

LncRNA SNHG14 is beneficial to oxygen glucose deprivation/reoxygenation-induced neuro-2a cell injury via mir-98-5p sequestration-caused BCL2L13 upregulation

BACKGROUND

The deregulation of long non-coding RNA (lncRNA) is associated with diverse human disorders, including cerebral ischemia/reperfusion injury (CI/RI). LncRNA SNHG14 was reported to function in CI/RI. Whereas, molecular mechanisms regulated by SNHG14 are not fully unveiled.

METHODS

Mice subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) were used as CI/RI animal models. Neuro-2a (N2A) cells subjected to oxygen glucose deprivation/reoxygenation (OGD/R) were used as CI/RI cell models. The expression of SNHG14, miR-98-5p and BCL2 like 13 (BCL2L13) was examined using quantitative real-time PCR (qPCR) or western blot. Apoptosis was monitored by flow cytometry assay. Apoptosis-related markers and endoplasmic reticulum (ER) stress-related markers were quantified by western blot. Inflammatory factors and oxidative stress were detected using matched commercial kits. The predicted relationship between miR-98-5p and SNHG14 or BCL2L13 was validated by dual-luciferase reporter assay, RIP assay and pull-down assay.

RESULTS

The high expression of SNHG14 was monitored in MCAO/R-treated mice and OGD/R-treated N2A cells. OGD/R-induced N2A cell apoptosis, ER stress, inflammation and oxidative stress were attenuated by SNHG14 knockdown. SNHG14 targeted miR-98-5p to positively regulate BCL2L13 expression. Inhibition of miR-98-5p recovered cell apoptosis, ER stress, inflammation and oxidative stress that were repressed by SNHG14 knockdown. Overexpression of BCL2L13 enhanced cell apoptosis, ER stress, inflammation and oxidative stress that were repressed by miR-98-5p enrichment.

CONCLUSIONS

SNHG14 knockdown alleviated OGD/induced N2A cell apoptosis, ER stress, inflammation and oxidative stress by depleting BCL2L13 via increasing miR-98-5p.

TNF-α Induces Neutrophil Apoptosis Delay and Promotes Intestinal Ischemia-Reperfusion-Induced Lung Injury through Activating JNK/FoxO3a Pathway

Background

Intestinal ischemia is a common clinical critical illness. Intestinal ischemia-reperfusion (IIR) leads to acute lung injury (ALI), but the causative factors of ALI are unknown. The aim of this study was to reveal the causative factors and mechanisms of IIR-induced lung injury.

Methods

A mouse model of IIR was developed using C57BL/6 mice, followed by detection of lung injury status and plasma levels of inflammatory factors in sham-operated mice and model mice. Some model mice were treated with a tumor necrosis factor-α (TNF-α) inhibitor lenalidomide (10 mg/kg), followed by observation of lung injury status through hematoxylin and eosin staining and detection of neutrophil infiltration levels through naphthol esterase and Ly6G immunohistochemical staining. Additionally, peripheral blood polymorphonuclear neutrophils (PMNs) were cultured in vitro and then stimulated by TNF-α to mimic in vivo inflammatory stimuli; this TNF-α stimulation was also performed on PMNs after knockdown of FoxO3a or treatment with the c-Jun N-terminal kinase (JNK) inhibitor SP600125. PMN apoptosis after stimulation was detected using flow cytometry. Finally, the role of PMN apoptosis in IIR-induced lung injury was evaluated in vivo by detecting the ALI status in the model mice administered with ABT-199, a Bcl-2 inhibitor.

Results

IIR led to pulmonary histopathological injury and increased lung water content, which were accompanied by increased plasma levels of inflammatory factors, with the TNF-α plasma level showing the most pronounced increase. Inhibition of TNF-α led to effective reduction of lung tissue injury, especially that of the damaging infiltration of PMNs in the lung. In vitro knockdown of FoxO3a or inhibition of JNK activity could inhibit TNF-α-induced PMN apoptosis. Further in vivo experiments revealed that ABT-199 effectively alleviated lung injury and decreased inflammation levels by promoting PMN apoptosis during IIR-induced lung injury.

Conclusion

TNF-α activates the JNK/FoxO3a pathway to induce a delay in PMN apoptosis, which promotes IIR-induced lung injury.

LncRNA MALAT1 promotes osteogenic differentiation of BMSCs and inhibits osteoclastic differentiation of Mø in osteoporosis via the miR-124-3p/IGF2BP1/Wnt/β-catenin axis

Osteoporosis is defined as a skeletal disorder characterized by impairment in bone strength. The potential application of lncRNAs as therapeutic targets for osteoporosis has been unveiled. This study investigated the regulatory mechanism of lncRNA MALAT1 in the differentiation of bone marrow stem cells (BMSCs) and macrophages (Mø) in osteoporosis. MALAT1 expression in peripheral blood of elderly osteoporosis patients and healthy volunteers was detected. BMSCs and mononuclear Mø were isolated and cultured. Osteogenic differentiation of BMSCs and osteoclastic differentiation of Mø were induced. BMSCs and Mø were transfected with si-MALAT1, miR-124-3p mimics, miR-124-3p inhibitor, or pcDNA IGF2BP1, followed by detection of cell differentiation. The target microRNAs (miRs) and downstream genes and signaling pathways of MALAT1 were examined. The ovariectomy-induced mouse model of osteoporosis was established, and the mice were injected with pcDNA-MALAT1. MALAT1 was downregulated in osteoporosis patients, increased in BMSCs after osteogenic differentiation, and diminished in Mø after osteoclastic differentiation. Downregulation of MALAT1 repressed osteogenic differentiation of BMSCs and facilitated osteoclastic differentiation of Mø. MALAT1 upregulated IGF2BP1 expression by competitively binding to miR-124-3p. miR-124-3p silencing reversed the effect of si-MALAT1 on BMSCs and Mø differentiation, and IGF2BP1 upregulation averted the effect of overexpressed-miR-124-3p by activating the Wnt/β-catenin pathway. Upregulation of MALAT1 activated the Wnt/β-catenin pathway and attenuated bone injury in mice. In conclusion, lncRNA MALAT1 promoted the osteogenic differentiation of BMSCs and inhibited osteoclastic differentiation of Mø in osteoporosis via the miR-124-3p/IGF2BP1/Wnt/β-catenin axis. This article is protected by copyright. All rights reserved.