Knockdown of lncRNA TTTY15 alleviates myocardial ischemia-reperfusion injury through the miR-374a-5p/FOXO1 axis

Marine anticancer drugs in modulating miRNAs and antioxidant signaling

Several marine drugs exert anticancer effects by inducing oxidative stress, which becomes overloaded and kills cancer cells when redox homeostasis is imbalanced. The downregulation of antioxidant signaling induces oxidative stress, while its upregulation attenuates oxidative stress. Marine drugs have miRNA-modulating effects against cancer cells. However, the potential antioxidant targets of such drugs have been rarely explored. This review aims to categorize the marine-drug-modulated miRNAs that downregulate their antioxidant targets, causing oxidative stress in anticancer treatments. We also categorize the downregulation of oxidative-stress-inducing miRNAs in antioxidant protection among non-cancer cells. We summarize the putative antioxidant targets of miRNA-modulating marine drugs by introducing a bioinformatics tool (miRDB). Finally, the marine drugs affecting antioxidant targets are surveyed. In this way, the connections between marine drugs and their modulating miRNA and antioxidant targets are innovatively categorized to provide a precise network for exploring their potential anticancer functions and protective effects on non-cancer cells.

Mechanisms by which silencing long-stranded noncoding RNA KCNQ1OT1 alleviates myocardial ischemia/reperfusion injury (MI/RI)-induced cardiac injury via miR-377-3p/HMOX1

BACKGROUND

The key complication of myocardial infarction therapy is myocardial ischemia/reperfusion injury (MI/RI), and there is no effective treatment. The present study elucidates the mechanism of action of lncRNA KCNQ1OT1 in alleviating MI/RI and provides new perspectives and therapeutic targets for cardiac injury-related diseases.

METHODS

An ischemia/reperfusion (I/R) injury model of human adult cardiac myocytes (HACMs) was constructed, and the expression of KCNQ1OT1 and miR-377-3p was determined by RT‒qPCR. The levels of related proteins were detected by western blot analysis. Cell proliferation was detected by a CCK-8 assay, and cell apoptosis and ROS content were determined by flow cytometry. SOD and MDA expression as well as Fe2+ changes were detected by related analysis kits. The target binding relationships between lncRNA KCNQ1OT1 and miR-377-3p as well as between miR-377-3p and heme oxygenase 1 (HMOX1) were verified by a dual-luciferase reporter gene assay.

RESULTS

Myocardial ischemia‒reperfusion caused oxidative stress in HACMs, resulting in elevated ROS levels, increased Fe2+ levels, decreased cell viability, and increased LDH release (a marker of myocardial injury), and apoptosis. KCNQ1OT1 and HMOX1 were upregulated in I/R-induced myocardial injury, but the level of miR-377-3p was decreased. A dual-luciferase reporter gene assay indicated that lncRNA KCNQ1OT1 targets miR-377-3p and that miR-377-3p targets HMOX1. Inhibition of HMOX1 alleviated miR-377-3p downregulation-induced myocardial injury. Furthermore, lncRNA KCNQ1OT1 promoted the level of HMOX1 by binding to miR-377-3p and aggravated myocardial injury.

CONCLUSION

LncRNA KCNQ1OT1 aggravates ischemia‒reperfusion-induced cardiac injury via miR-377-3P/HMOX1.

Emerging role of the gut microbiome in post-infectious irritable bowel syndrome: A literature review

Post-infectious irritable bowel syndrome (PI-IBS) is a particular type of IBS, with symptom onset after an acute episode of infectious gastroenteritis. Despite infectious disease resolution and clearance of the inciting pathogen agent, 10% of patients will develop PI-IBS. In susceptible individuals, the exposure to pathogenic organisms leads to a marked shift in the gut microbiota with prolonged changes in host-microbiota interactions. These changes can affect the gut-brain axis and the visceral sensitivity, disrupting the intestinal barrier, altering neuromuscular function, triggering persistent low inflammation, and sustaining the onset of IBS symptoms. There is no specific treatment strategy for PI-IBS. Different drug classes can be used to treat PI-IBS similar to patients with IBS in general, guided by their clinical symptoms. This review summarizes the current evidence for microbial dysbiosis in PI-IBS and analyzes the available data regarding the role of the microbiome in mediating the central and peripheral dysfunctions that lead to IBS symptoms. It also discusses the current state of evidence on therapies targeting the microbiome in the management of PI-IBS. The results of microbial modulation strategies used in relieving IBS symptomatology are encouraging. Several studies on PI-IBS animal models reported promising results. However, published data that describe the efficacy and safety of microbial targeted therapy in PI-IBS patients are scarce. Future research is required.

Epigenetic regulation in myocardial infarction: Non-coding RNAs and exosomal non-coding RNAs

Myocardial infarction (MI) is one of the leading causes of deaths globally. The early diagnosis of MI lowers the rate of subsequent complications and maximizes the benefits of cardiovascular interventions. Many efforts have been made to explore new therapeutic targets for MI, and the therapeutic potential of non-coding RNAs (ncRNAs) is one good example. NcRNAs are a group of RNAs with many different subgroups, but they are not translated into proteins. MicroRNAs (miRNAs) are the most studied type of ncRNAs, and have been found to regulate several pathological processes in MI, including cardiomyocyte inflammation, apoptosis, angiogenesis, and fibrosis. These processes can also be modulated by circular RNAs and long ncRNAs via different mechanisms. However, the regulatory role of ncRNAs and their underlying mechanisms in MI are underexplored. Exosomes play a crucial role in communication between cells, and can affect both homeostasis and disease conditions. Exosomal ncRNAs have been shown to affect many biological functions. Tissue-specific changes in exosomal ncRNAs contribute to aging, tissue dysfunction, and human diseases. Here we provide a comprehensive review of recent findings on epigenetic changes in cardiovascular diseases as well as the role of ncRNAs and exosomal ncRNAs in MI, focusing on their function, diagnostic and prognostic significance.

New developments in non-exosomal and exosomal ncRNAs in coronary artery disease

Aim & methods: Non-exosomal and exosomal ncRNAs have been reported to be involved in the regulation of coronary artery disease (CAD). Therefore, to explore the biological effects of non-exosomal/exosomal ncRNAs in CAD, the authors searched for studies published in the last 3 years on these ncRNAs in CAD and summarized their functions and mechanisms. Results: The authors summarized 120 non-exosomal ncRNAs capable of regulating CAD progression. In clinical studies, 47 non-exosomal and nine exosomal ncRNAs were able to serve as biomarkers for the diagnosis of CAD. Conclusion: Non-exosomal/exosomal ncRNAs are not only able to serve as biomarkers for CAD diagnosis but can also regulate CAD progression through ceRNA mechanisms and are a potential target for early clinical intervention in CAD.

miR‑374a‑5p alleviates sepsis‑induced acute lung injury by targeting ZEB1 via the p38 MAPK pathway

The aim of the present study was to investigate the effects of microRNA (miR)-374a-5p on sepsis-induced acute lung injury (ALI) and the associated mechanism. Lipopolysaccharide (LPS)-induced human pulmonary microvascular endothelial cells (HPMVECs) were used to construct the cellular model of sepsis. A luciferase reporter assay was performed to confirm the association between miR-374a-5p and zinc finger E-box binding homeobox 1 (ZEB1). Reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to assess the relative expression of miR-374a-5p, ZEB1 and apoptosis-related proteins. Cell viability and apoptosis were determined by Cell Counting Kit-8 assay and flow cytometry, respectively. Enzyme-linked immunosorbent assays were used to evaluate inflammatory cytokines. The results revealed that miR-374a-5p was downregulated in sepsis patients and LPS-treated HPMVECs. Upregulation of miR-374a-5p alleviated LPS-triggered cell injury in HPMVECs, as evidenced by restoration of cell viability, and inhibition of apoptosis and the production of proinflammatory cytokines. In addition, ZEB1 was revealed to be a downstream target of miR-374a-5p, and overexpression of ZEB1 could reverse the anti-apoptotic and anti-inflammatory effects of miR-374a-5p on an LPS-induced sepsis cell model. Moreover, miR-374a-5p-induced protective effects involved the p38 MAPK signaling pathway. Collectively, miR-374a-5p exerted a protective role in sepsis-induced ALI by regulating the ZEB1-mediated p38 MAPK signaling pathway, providing a potential target for the diagnosis and treatment of sepsis.

Delivery of Chondrocyte-Targeting sh-TTTY15 (Testis-Specific Transcript, Y-Linked 15) Nanoparticles Against LncRNA TTTY15 Improves Osteoarthritis by Regulating Autophagy and Oxidative Stress

Objective: To explore the potential role of hyaluronic acid-modified peptide-lncRNA TTTY15 nanoparticles in joint injury of chondrocytes in OA rats. Methods: Cell proliferation, apoptosis and oxidative stress were tested by CCK8, flow cytometry and biochemical analysis. Histopathology and LC3 expression were analyzed by HE, TUNEL and IF. The expression levels of TTTY15, LC3, p62, c-caspase3, Col2A1, ACAN, ADAMTS-5 and MMP13 were tested by RT–qPCR, western blotting and IHC. Autophagosomes were observed by TEM. Results: Bioinformatics and RT–PCR analyses showed that TTTY15 was highly expressed in OA- and TBHP-stimulated chondrocytes. Ov-TTTY15 aggravated TBHP-induced activity decreases, apoptosis, oxidative stress, ECM degradation and autophagic flux reduction in chondrocytes. HA-coated-p5RHH-sh-TTTY15 nanoparticle intervention enhanced the stability and prolonged TTTY15 silencing in chondrocytes. HA-coated-p5RHH-sh-TTTY15 nanoparticles inhibited TBHP-induced C-28/I2 cell damage and activated autophagy, and the inhibitory effect was greater than that of sh-TTTY15. Conclusion: HA-coated-p5RHH-sh-TTTY15 nanoparticles enhanced the stable silencing of TTTY15 in chondrocytes; promoted cell proliferation; inhibited apoptosis, oxidative stress and ECM degradation; and activated autophagy to improve joint injury in OA rats.

The Regulatory Role of Non-coding RNA in Autophagy in Myocardial Ischemia-Reperfusion Injury

Following an acute myocardial infarction (AMI), thrombolysis, coronary artery bypass grafting and primary percutaneous coronary intervention (PPCI) are the best interventions to restore reperfusion and relieve the ischemic myocardium, however, the myocardial ischemia-reperfusion injury (MIRI) largely offsets the benefits of revascularization in patients. Studies have demonstrated that autophagy is one of the important mechanisms mediating the occurrence of the MIRI, while non-coding RNAs are the main regulatory factors of autophagy, which plays an important role in the autophagy-related mTOR signaling pathways and the process of autophagosome formation Therefore, non-coding RNAs may be used as novel clinical diagnostic markers and therapeutic targets in the diagnosis and treatment of the MIRI. In this review, we not only describe the effect of non-coding RNA regulation of autophagy on MIRI outcome, but also zero in on the regulation of non-coding RNA on autophagy-related mTOR signaling pathways and mitophagy. Besides, we focus on how non-coding RNAs affect the outcome of MIRI by regulating autophagy induction, formation and extension of autophagic vesicles, and the fusion of autophagosome and lysosome. In addition, we summarize all non-coding RNAs reported in MIRI that can be served as possible druggable targets, hoping to provide a new idea for the prediction and treatment of MIRI.

Transcription factor JDP2 activates PDE4B to participate in hypoxia/reoxygenation‑induced H9c2 cell injury

Myocardial ischemia/reperfusion (I/R) injury is a clinical challenge in the treatment of acute myocardial infarction (AMI). Phosphodiesterase 4B (PDE4B) expression is upregulated in AMI tissues. Thus, the present study aimed to investigate the role of PDE4B in myocardial I/R injury. H9c2 cardiomyocytes were subjected to hypoxia/reoxygenation (H/R) to establish an in vitro myocardial I/R model. PDE4B expression was detected via reverse transcription-quantitative PCR (RT-qPCR) and western blotting before and after transfection with PDE4B interference plasmids in H/R-stimulated H9c2 cells. Cell viability and cytotoxicity were assessed using the Cell Counting Kit-8 and lactate dehydrogenase assays, respectively. Furthermore, oxidative stress was assessed using malondialdehyde, superoxide dismutase and glutathione/glutathione oxidized ratio detection kits. Cell apoptosis was detected via a TUNEL assay and western blotting. c-Jun dimerization protein 2 (JDP2) expression was also detected via RT-qPCR and western blotting. The dual luciferase reporter and chromatin immunoprecipitation assays were performed to verify the interaction between JDP2 and PDE4B. Following co-transfection with PDE4B interference plasmid and JDP2 overexpression plasmid, cell viability, cytotoxicity, oxidative stress and cell apoptosis were assessed. The results demonstrated that PDE4B knockdown reversed H/R-induced loss of viability and cytotoxicity of H9c2 cells. H/R-induced oxidative stress and cardiomyocyte apoptosis were also alleviated by PDE4B knockdown. In addition, the transcription factor JDP2 was expressed at high levels in H/R-stimulated H9c2 cells, and JDP2 overexpression upregulated PDE4B expression. Notably, JDP2 overexpression partly reversed the ameliorative effect of PDE4B knockdown on H/R-induced H9c2 injury. Taken together, the results of the present study suggested that JDP2-activated PDE4B contributed to H/R-induced H9c2 cell injury.

Long non-coding RNA TTTY15 silencing inhibits gastric cancer progression by sponging microRNA-98-5p to down-regulate cyclin D2 expression

Gastric cancer is the most common malignant tumor in the digestive system. However, the detection rate of early gastric cancer is low, resulting in delayed prognosis and poor outcomes. The identification of effective therapeutic targets for gastric cancer is, therefore, of profound significance. Recently, various lncRNAs have been shown to be biomarkers for different cancers. This study investigated the role of long non-coding RNA (lncRNA) TTTY15 in gastric cancer. The expression level of TTTY15, miR-98-5p, and cyclin D2 (CCND2) were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot assay using tumor and non-tumor tissues collected from 30 patients with gastric cancer, gastric cancer cell lines (AGS, SNU-5, and NCI-N87), and the normal gastric epithelial cell line GES-1. The interaction between TTTY15 and miR-98-5p and between miR-98-5p and CCND2 were predicted by bioinformatics and then further verified by dual-luciferase and RNA pull-down analyses. Cell proliferation was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2 H-tetrazolium bromide (MTT) assay, and apoptosis was measured using flow cytometry and caspase-3 assay. The results indicate that TTTY15 and CCND2 expression increased and miR-98-5p expression decreased in gastric cancer tumor tissues and cell lines. TTTY15 knockdown inhibited gastric cancer cell proliferation but promoted apoptosis by sponging miR-98-5p, which acted as a tumor suppressor gene by reducing the expression of its target gene CCND2 in gastric cancer. In conclusion, lncRNA TTTY15 is a potential oncogene involved in gastric cancer and may be a novel therapeutic target for gastric cancer treatment.

Non-coding RNAs modulate autophagy in myocardial ischemia-reperfusion injury: a systematic review

The myocardial infarction is the main cause of morbidity and mortality in cardiovascular diseases around the world. Although the timely and complete reperfusion via Percutaneous Coronary Intervention (PCI) or thrombolysis have distinctly decreased the mortality of myocardial infarction, reperfusion itself may lead to supererogatory irreversible myocardial injury and heart function disorders, namely ischemia-reperfusion (I/R) injury. Extensive studies have indicated that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), play important roles in the progress of myocardial I/R injury, which is closely correlative with cardiomyocytes autophagy. Moreover, autophagy plays an important role in maintaining homeostasis and protecting cells in the myocardial ischemia reperfusion and cardiomyocyte hypoxia-reoxygenation (H/R) progress. In this review, we first introduced the biogenesis and functions of ncRNAs, and subsequently summarized the roles and relevant molecular mechanisms of ncRNAs regulating autophagy in myocardial I/R injury. We hope that this review in addition to develop a better understanding of the physiological and pathological roles of ncRNAs, can also lay a foundation for the therapies of myocardial I/R injury, and even for other related cardiovascular diseases.

MiR-27a-3p suppresses cerebral ischemia-reperfusion injury by targeting FOXO1

Cerebral ischemia-reperfusion (CI/R) injury is a serious complication when treating patients experiencing ischemic stroke. Although the microRNA miR-27a-3p reportedly participates in ischemia/reperfusion (I/R) injury, its actions in CI/R remain unclear. To mimic CI/R in vitro, HT22 cells were subjected to oxygen glucose deprivation/reoxygenation (OGD/R). The results indicate that OGD inhibited growth and induced apoptosis among HT22 cells. The apoptosis was accompanied by increases in activated caspases 3 and 9 and decreases in Bcl-2. Oxidative stress was also increased, as indicated by increases in ROS and malondialdehyde and decreases in glutathione and superoxide dismutase. In addition, OGD induced G1 arrest in HT22 cells with corresponding upregulation of FOXO1 and p27 Kip1, suggesting the cell cycle arrest was mediated by FOXO1/p27 Kip1 signaling. Notably, FOXO1 was found to be the direct target of miR-27a-3p in HT22 cells. MiR-27a-3p was downregulated in OGD/R-treated HT22 cells, and miR-27a-3p mimics partially or entirely reversed all of the in vitro effects of OGD. Moreover, miR-27a-3p agomir significantly alleviated the symptoms of CI/R in vivo in a rat model of CI/R. Thus, MiR-27a-3p appears to suppress CI/R injury by targeting FOXO1.