NDRG1 Signaling Is Essential for Endothelial Inflammation and Vascular Remodeling.

BACKGROUND: NDRG-1 (N-myc downstream-regulated gene 1) is a member of NDRG family that plays essential roles in cell differentiation, proliferation, and stress responses. Although the expression of NDRG1 is regulated by fluid shear stress, its roles in vascular biology remain poorly understood. The purpose of the study is to determine the functional significance of NDRG1 in vascular inflammation and remodeling. METHODS AND RESULTS: By using quantitative polymerase chain reaction, western blot, and immunohistochemistry, we demonstrate that the expression of NDRG1 is markedly increased in cytokine-stimulated endothelial cells and in human and mouse atherosclerotic lesions. To determine the role of NDRG1 in endothelial activation, we performed loss-of-function studies using NDRG1 short hairpin RNA. Our results demonstrate that NDRG1 knockdown by lentivirus bearing NDRG1 short hairpin RNA substantially attenuates both IL-1ß (interleukin-1ß) and TNF-α (tumor necrosis factor-α)-induced expression of cytokines/chemokines and adhesion molecules. Intriguingly, inhibition of NDRG1 also significantly attenuates the expression of procoagulant molecules, such as PAI-1 (plasminogen activator inhibitor type 1) and TF (tissue factor), and increases the expression of TM (thrombomodulin) and t-PA (tissue-type plasminogen activator), thus exerting potent antithrombotic effects in endothelial cells. Mechanistically, we showed that NDRG1 interacts with orphan Nur77 (nuclear receptor) and functionally inhibits the transcriptional activity of Nur77 and NF-κB (nuclear factor Kappa B) in endothelial cells. Moreover, in NDRG1 knockdown cells, both cytokine-induced mitogen-activated protein kinase activation, c-Jun phosphorylation, and AP-1 (activator protein 1) transcriptional activity are substantially inhibited. Neointima and atherosclerosis formation induced by carotid artery ligation and arterial thrombosis were markedly attenuated in endothelial cell-specific NDRG1 knockout mice compared with their wild-type littermates. CONCLUSIONS: Our results for the first time identify NDRG1 as a critical mediator implicated in regulating endothelial inflammation, thrombotic responses, and vascular remodeling, and suggest that inhibition of NDRG1 may represent a novel therapeutic strategy for inflammatory vascular diseases, such as atherothrombosis and restenosis.

Downregulation of NUP93 aggravates hypoxia-induced death of cardiomyocytes in vitro through abnormal regulation of gene transcription.

Nuclear pore complex in the nuclear envelope plays an important role in controlling the transportation of RNAs, proteins and other macromolecules between the nucleus and cytoplasm. The relationship between abnormal expression of nucleoporins and cardiovascular diseases is unclear. In this study we investigated how myocardial infarction affected the expression and function of nucleoporins in cardiomyocytes. We separately knocked down 27 nucleoporins in rat primary myocardial cells. Among 27 nucleoporins, knockdown of Nup93, Nup210 and Nup214 markedly increased the expression of ANP and BNP, two molecular markers of cardiomyocyte function. We showed that Nup93 was significantly downregulated in hypoxic cardiomyocytes. Knockdown of Nup93 aggravated hypoxia-induced injury and cell death of cardiomyocytes, whereas overexpression of Nup93 led to the opposite effects. RNA-seq and bioinformatics analysis revealed that knockdown of Nup93 did not affect the overall transportation of mRNAs from the nucleus to the cytoplasm, but regulated the transcription of a large number of mRNAs in cardiomyocytes, which are mainly involved in oxidative phosphorylation and ribosome subunits. Most of the down-regulated genes by Nup93 knockdown overlapped with the genes whose promoters could be directly bound by Nup93. Among these genes, we demonstrated that Nup93 knockdown significantly down-regulated the expression of YAP1. Overexpression of YAP1 partially rescued the function of Nup93 knockdown and attenuated the effects of hypoxia on cell injury and cardiomyocyte death. We conclude that down-regulation of Nup93, at least partially, contributes to hypoxia-induced injury and cardiomyocyte death through abnormal interaction with the genome to dynamically regulate the transcription of YAP1 and other genes. These results reveal a new mechanism of Nup93 and might provide new therapeutic targets for the treatment of ischemia-induced heart failure.

Characterization of ZmCOLD1, novel GPCR-Type G Protein genes involved in cold stress from Zea mays L. and the evolution analysis with those from other species.

Maize is one of the most vital staple crops worldwide. G proteins modulate plentiful signaling pathways, and G protein-coupled receptor-type G proteins (GPCRs) are highly conserved membrane proteins in plants. However, researches on maize G proteins and GPCRs are scarce. In this study, we identified three novel GPCR-Type G Protein (GTG) genes from chromosome 10 (Chr 10) in maize, designated as ZmCOLD1-10A, ZmCOLD1-10B and ZmCOLD1-10C. Their amino acid sequences had high similarity to TaCOLD1 from wheat and OsCOLD1 from rice. They contained the basic characteristics of GTG/COLD1 proteins, including GPCR-like topology, the conserved hydrophilic loop (HL) domain, DUF3735 (domain of unknown function 3735) domain, GTPase-activating domain, and ATP/GTP-binding domain. Subcellular localization analyses of ZmCOLD1 proteins suggested that ZmCOLD1 proteins localized on plasma membrane (PM) and endoplasmic reticulum (ER). Furthermore, amino acid sequence alignment verified the conservation of the key 187th amino acid T in maize and other wild maize-relative species. Evolutionary relationship among plants GTG/COLD1 proteins family displayed strong group-specificity. Expression analysis indicated that ZmCOLD1-10A was cold-induced and inhibited by light. Together, these results suggested that ZmCOLD1 genes had potential value to improve cold tolerance and to contribute crops growth and molecular breeding.

Transcriptional up-regulation of relaxin-3 by Nur77 attenuates ß-adrenergic agonist-induced apoptosis in cardiomyocytes.

The relaxin family peptides have been shown to exert several beneficial effects on the heart, including anti-apoptosis, anti-fibrosis, and anti-hypertrophy activity. Understanding their regulation might provide new opportunities for therapeutic interventions, but the molecular mechanism(s) coordinating relaxin expression in the heart remain largely obscured. Previous work demonstrated a role for the orphan nuclear receptor Nur77 in regulating cardiomyocyte apoptosis. We therefore investigated Nur77 in the hopes of identifying novel relaxin regulators. Quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) data indicated that ectopic expression of orphan nuclear receptor Nur77 markedly increased the expression of latexin-3 (RLN3), but not relaxin-1 (RLN1), in neonatal rat ventricular cardiomyocytes (NRVMs). Furthermore, we found that the ß-adrenergic agonist isoproterenol (ISO) markedly stimulated RLN3 expression, and this stimulation was significantly attenuated in Nur77 knockdown cardiomyocytes and Nur77 knockout hearts. We showed that Nur77 significantly increased RLN3 promoter activity via specific binding to the RLN3 promoter, as demonstrated by electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assays. Furthermore, we found that Nur77 overexpression potently inhibited ISO-induced cardiomyocyte apoptosis, whereas this protective effect was significantly attenuated in RLN3 knockdown cardiomyocytes, suggesting that Nur77-induced RLN3 expression is an important mediator for the suppression of cardiomyocyte apoptosis. These findings show that Nur77 regulates RLN3 expression, therefore suppressing apoptosis in the heart, and suggest that activation of Nur77 may represent a useful therapeutic strategy for inhibition of cardiac fibrosis and heart failure.

Nur77 limits endothelial barrier disruption to LPS in the mouse lung.

Nur77 is an orphan nuclear receptor implicated in the regulation of a wide range of biological processes, including the maintenance of systemic blood vessel homeostasis. Although Nur77 is known to be expressed in the lung, its role in regulating pulmonary vascular functions remains entirely unknown. In this study, we found that Nur77 is expressed at high levels in the lung, and its expression is markedly upregulated in response to LPS administration. While the pulmonary vasculature of mice that lacked Nur77 appeared to function normally under homeostatic conditions, we observed a dramatic decrease in its barrier functions after exposure to LPS, as demonstrated by an increase in serum proteins in the bronchoalveolar lavage fluid and a reduction in the expression of endothelial junctional proteins, such as vascular endothelial cadherin (VE-cadherin) and ß-catenin. Similarly, we found that siRNA knockdown of Nur77 in lung microvascular endothelial cells also reduced VE-cadherin and ß-catenin expression and increased the quantity of fluorescein isothiocyanate-labeled dextran transporting across LPS-injured endothelial monolayers. Consistent with Nur77 playing a vascular protective role, we found that adenoviral-mediated overexpression of Nur77 both enhanced expression of VE-cadherin and ß-catenin and augmented endothelial barrier protection to LPS in cultured cells. Mechanistically, Nur77 appeared to mediate its protective effects, at least in part, by binding to ß-catenin and preventing its degradation. Our findings demonstrate a key role for Nur77 in the maintenance of lung endothelial barrier protection to LPS and suggest that therapeutic strategies aimed at augmenting Nur77 levels might be effective in treating a wide variety of inflammatory vascular diseases of the lung.

Gene Regulation and Signal Transduction in the ICE-CBF-COR Signaling Pathway during Cold Stress in Plants.

Low temperature is an abiotic stress that adversely affects the growth and production of plants. Resistance and adaptation of plants to cold stress is dependent upon the activation of molecular networks and pathways involved in signal transduction and the regulation of cold-stress related genes. Because it has numerous and complex genes, regulation factors, and pathways, research on the ICE-CBF-COR signaling pathway is the most studied and detailed, which is thought to be rather important for cold resistance of plants. In this review, we focus on the function of each member, interrelation among members, and the influence of manipulators and repressors in the ICE-CBF-COR pathway. In addition, regulation and signal transduction concerning plant hormones, circadian clock, and light are discussed. The studies presented provide a detailed picture of the ICE-CBF-COR pathway.

Symptomatic sinus tachycardia with perpetuating slow pathway: successful treatment with radiofrequency ablation.

We report a case of sinus tachycardia with perpetuating slow pathway (SP) conduction in a 42-year-old woman who developed severe symptoms as a result of atrioventricular (AV) desynchronization. The restoration of an AV synchrony, achieved with selective radiofrequency ablation of the SP, eliminated the symptomatic arrhythmia and may represent a reasonable therapeutic option despite the fact that the patient has no AV-node reentrant tachycardia. This case demonstrates the importance of AV timing.

Transcriptomic and functional analyzes reveal that the brassinosteroid insensitive 1 receptor (OsBRI1) regulates cold tolerance in rice.

Brassinosteroids (BR) play crucial roles in plant development and abiotic stresses in plants. Exogenous application of BR can significantly enhance cold tolerance in rice. However, the regulatory relationship between cold tolerance and the BR signaling pathway in rice remains largely unknown. Here, we characterized functions of the BR receptor OsBRI1 in response to cold tolerance in rice using its loss-of-function mutant (d61-1). Our results showed that mutant d61-1 was less tolerant to cold stress than wild-type (WT). Besides, d61-1 had lower levels than WT for some physiological parameters, including catalase activity (CAT), superoxide dismutase activity (SOD), peroxidase activity (POD), peroxidase activity (PRO), soluble protein, and soluble sugar content, while malondialdehyde content (MDA) and relative electrical conductivity (REC) levels in d61-1 were higher than those in WT plants. These results indicated that the loss of OsBRI1 function resulted in decreased cold tolerance in rice. In addition, we performed RNA sequencing (RNA-seq) of WT and d61-1 mutant under cold stress. Numerous common and unique differentially expressed genes (DEGs) with up- and down-regulation were observed in WT and d61-1 mutant. Some DEGs were expressed to various degrees, even opposite, between CK1 vs. T1 (WT) and CK2 vs. T2 (d61-1). Among these specific DEGs, some typical genes are involved in plant tolerance to cold stress. Through weighted correlation network analysis (WGCNA), 50 hub genes were screened in the turquoise and blue module. Many genes were involved in cold stress and plant hormone, such as Os01g0279800 (BRI1-associated receptor kinase 1 precursor), Os10g0513200 (Dwarf and tiller-enhancing 1, DTE1), Os02g0706400 (MYB-related transcription factor, OsRL3), etc. Differential expression levels of some genes were verified in WT and d61-1 under cold stress using qRT-PCR. These valuable findings and gene resources will be critical for understanding the regulatory relationships between cold stress tolerance and the BR signaling pathways in rice.

Abnormal expression of PRKAG2-AS1 in endothelial cells induced inflammation and apoptosis by reducing PRKAG2 expression.

PRKAG2 is required for the maintenance of cellular energy balance. PRKAG2-AS1, a long non-coding RNA (lncRNA), was found within the promoter region of PRKAG2. Despite the extensive expression of PRKAG2-AS1 in endothelial cells, the precise function and mechanism of this gene in endothelial cells have yet to be elucidated. The localization of PRKAG2-AS1 was predominantly observed in the nucleus, as revealed using nuclear and cytoplasmic fractionation and fluorescence in situ hybridization. The manipulation of PRKAG2-AS1 by knockdown and overexpression within the nucleus significantly altered PRKAG2 expression in a cis-regulatory manner. The expression of PRKAG2-AS1 and its target genes, PRKAG2b and PRKAG2d, was down-regulated in endothelial cells subjected to oxLDL and Hcy-induced injury. This finding suggests that PRKAG2-AS1 may be involved in the mechanism behind endothelial injury. The suppression of PRKAG2-AS1 specifically in the nucleus led to an upregulation of inflammatory molecules such as cytokines, adhesion molecules, and chemokines in endothelial cells. Additionally, this nuclear suppression of PRKAG2-AS1 facilitated the adherence of THP1 cells to endothelial cells. We confirmed the role of nuclear knockdown PRKAG2-AS1 in the induction of apoptosis and inhibition of cell proliferation, migration, and lumen formation through flow cytometry, TUNEL test, CCK8 assay, and cell scratching. Finally, it was determined that PRKAG2-AS1 exerts direct control over the transcription of PRKAG2 by its binding to their promoters. In conclusion, downregulation of PRKAG2-AS1 suppressed the proliferation and migration, promoted inflammation and apoptosis of endothelial cells, and thus contributed to the development of atherosclerosis resulting from endothelial cell injury.

Intraplatelet miRNA-126 regulates thrombosis and its reduction contributes to platelet inhibition.

AIMS: MicroRNA-126 (miR-126), one of the most abundant microRNAs in platelets, is involved in the regulation of platelet activity and the circulating miR-126 is reduced during antiplatelet therapy. However, whether intraplatelet miR-126 plays a role in thrombosis and platelet inhibition remains unclear. METHODS AND RESULTS: Here, using tissue-specific knockout mice, we reported that the deficiency of miR-126 in platelets and vascular endothelial cells significantly prevented thrombosis and prolonged bleeding time. Using chimeric mice, we identified that the lack of intraplatelet miR-126 significantly prevented thrombosis. Ex vivo experiments further demonstrated that miR-126-deficient platelets displayed impaired platelet aggregation, spreading and secretory functions. Next, miR-126 was confirmed to target phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2) in platelet, which encodes a negative regulator of the PI3 K/AKT pathway, enhancing platelet activation through activating the integrin αIIbß3-mediated outside-in signaling. After undergoing myocardial infarction (MI), chimeric mice lacking intraplatelet miR-126 displayed reduced microvascular obstruction and prevented MI expansion in vivo. In contrast, overexpression of miR-126 by the administration of miR-126 agonist (agomiR-126) in wild-type mice aggravated microvascular obstruction and promoted MI expansion, which can be almost abolished by aspirin administration. In patients with cardiovascular diseases, antiplatelet therapies, either aspirin alone or combined with clopidogrel, decreased the level of intraplatelet miR-126. The reduction of intraplatelet miR-126 level was associated with the decrease of platelet activity. CONCLUSIONS: Our murine and human data reveal that (i) intraplatelet miR-126 contributes to platelet activity and promotes thrombus formation, and (ii) the reduction of intraplatelet miR-126 contributes to platelet inhibition during antiplatelet therapy.

Molecular switch for cold acclimation -- anatomy of the cold-inducible promoter in plants.

In plants, a promoter is essential to drive the transcription and expression of genes under stress conditions. The cold-regulated promoter is an important molecular switch involved in transcriptional regulation of a dynamic network of genes associated with cold acclimation processes. However, the structure and functions of the cold-regulated promoter are ambiguous. In this review, we first describe the common type and structures of the cold-regulated promoter, such as the core promoter and transcription factor binding sites, and then discuss the synergistic actions of promoter elements and cold-regulated genes. We also describe the transcriptional responses and cross-talk among cold-regulated genes in the ICE-CBF-COR cold-response pathway. Many stress-inducible genes are known to be regulated by endogenous abscisic acid (ABA), which accumulates during osmotic and cold stress. We discuss the regulation of promoters of cold-inducible genes in ABA-dependent and ABA-independent regulatory systems. We also describe the cross-talk among gene networks regulated by different cis-acting regulatory elements. Finally, we propose potential further research on, and practical applications of, the cold-regulated promoter.

Di-(2-ethylhexyl) phthalate impairs angiogenesis and hematopoiesis via suppressing VEGF signaling in zebrafish.

Di-(2-ethylhexyl) phthalate (DEHP) is among the most widely used plasticizers in plastic production, which has been detected in various environments. However, DEHP safety remains poorly known. Using zebrafish models, the effects of DEHP on the angiogenesis and hematopoiesis, and the underlying mechanism, were studied. Transgenic zebrafish embryos with specific fluorescence of vascular endothelial cells, myeloid cells, or hematopoietic stem cells were exposed to 0, 100, 150, 200, or 250 nM of DEHP for 22, 46 or 70 h, followed by fluorescence observation, endogenous alkaline phosphatase activity measurement, erythrocyte staining, and gene expression analysis by quantitative PCR and whole mount in situ hybridization. High DEHP concentrations decreased the sprouting rate, average diameter, and length, and the expansion area of the vessels lowered the EAP activity and suppressed the vascular endothelial growth factor (vegf) and hematopoietic marker genes, including c-myb, hbae1, hbbe1, and lyz expressions. DEHP treatment also decreased the number of hematopoietic stem cells, erythrocytes, and myeloid cells at 24 and 72 hpf. These DEHP-induced angiogenetic and hematopoietic defects might be alleviated by vegf overexpression. Our results reveal a plausible mechanistic link between DEHP exposure-induced embryonic angiogenetic defect and hematopoietic impairment.

Epigenetic regulation of vascular smooth muscle cell phenotypic switch and neointimal formation by PRMT5.

AIMS: Phenotypic transition of vascular smooth muscle cells (VSMCs) from a contractile to a synthetic state is involved in the development of cardiovascular diseases, including atherosclerosis, hypertension, and post-angioplasty restenosis. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs) has been implicated in multiple cellular processes, however, its role in VSMC biology remains undetermined. The objective of this study was to determine the role of PRMTs in VSMC phenotypic switch and vascular remodelling after injury. METHODS AND RESULTS: Our results show that PRMT5 is the most abundantly expressed PRMT in human aortic SMCs, and its expression is up-regulated in platelet-derived growth factor (PDGF)-stimulated VSMCs, human atherosclerotic lesions, and rat carotid arteries after injury, as determined by western blot and immunohistochemical staining. PRMT5 overexpression inhibits the expression of SMC marker genes and promotes VSMC proliferation and migration, while silencing PRMT5 exerts the opposite effects. Mechanistically, we found that PRMT5 overexpression led to histone di-methylation of H3R8 and H4R3, which in turn attenuates acetylation of H3K9 and H4, thus limiting recruitment of the SRF/myocardin complexes to the CArG boxes of SMC marker genes. Furthermore, both SMC-specific deletion of PRMT5 in mice and local delivery of lentivirus expressing shPRMT5 to rat carotid arteries significantly attenuated neointimal formation after injury. Likewise, pharmacological inhibition of PRMT5 by EPZ015666 markedly inhibited carotid artery ligation-induced neointimal formation in mice. CONCLUSIONS: Our results identify PRMT5 as a novel regulator in VSMC phenotypic switch and suggest that inhibition of PRMT5 may represent an effective therapeutic strategy for proliferative vascular diseases.

Inhibiting endothelial cell Mst1 attenuates acute lung injury in mice.

Background: Lung endothelium plays a pivotal role in the orchestration of inflammatory and injury responses to acute pulmonary insults. Mammalian sterile 20-like kinase 1 (Mst1), a mammalian homolog of Hippo, is a serine/threonine kinase that is ubiquitously expressed in many tissues and has been shown to play an important role in the regulation of apoptosis, inflammation, stress responses, and organ growth. While Mst1 exhibits high expression in the lung, its involvement in the endothelial response to pulmonary insults remains largely unexplored. Methods: Mst1 activity was assessed in lung endothelium by western blot. Mst1 endothelial specific knockout mice and a pharmacological inhibitor were employed to assess the effects of Mst1 on homeostatic and lipopolysaccharide (LPS)-induced endothelial responses. Readouts for these studies included various assays, including NF-κB activation and levels of various inflammatory cytokines and adhesion molecules. The role of Mst1 in lung injury was evaluated in a LPS-induced murine model of acute lung injury (ALI). Results: Mst1 phosphorylation was significantly increased in lung endothelial cells after exposure to tumor necrosis factor (TNF)-alpha (TNF-α) and mouse lung tissues after LPS exposure. Overexpression of full length Mst1 or its kinase domain promoted nuclear factor kappaB (NF-κB) activation through promoting JNK and p38 activation, whereas dominant negative forms of Mst1 (DN-Mst1) attenuated endothelial responses to TNF-α and interleukin-1ß. Consistent with this, targeted deletion of Mst1 in lung endothelium reduced lung injury to LPS in mice. Similarly, wild-type mice were protected from LPS-induced lung injury following treatment with a pharmacological inhibitor of Mst1/2. Conclusions: Our findings identified Mst1 kinase as a key regulator in the control of lung EC activation and suggest that therapeutic strategies aimed at inhibiting Mst1 activation might be effective in the prevention and treatment of lung injury to inflammatory insults.

PIMT is a novel and potent suppressor of endothelial activation.

Proinflammatory agonists provoke the expression of cell surface adhesion molecules on endothelium in order to facilitate leukocyte infiltration into tissues. Rigorous control over this process is important to prevent unwanted inflammation and organ damage. Protein L-isoaspartyl O-methyltransferase (PIMT) converts isoaspartyl residues to conventional methylated forms in cells undergoing stress-induced protein damage. The purpose of this study was to determine the role of PIMT in vascular homeostasis. PIMT is abundantly expressed in mouse lung endothelium and PIMT deficiency in mice exacerbated pulmonary inflammation and vascular leakage to LPS(lipopolysaccharide). Furthermore, we found that PIMT inhibited LPS-induced toll-like receptor signaling through its interaction with TNF receptor-associated factor 6 (TRAF6) and its ability to methylate asparagine residues in the coiled-coil domain. This interaction was found to inhibit TRAF6 oligomerization and autoubiquitination, which prevented NF-κB transactivation and subsequent expression of endothelial adhesion molecules. Separately, PIMT also suppressed ICAM-1 expression by inhibiting its N-glycosylation, causing effects on protein stability that ultimately translated into reduced EC(endothelial cell)-leukocyte interactions. Our study has identified PIMT as a novel and potent suppressor of endothelial activation. Taken together, these findings suggest that therapeutic targeting of PIMT may be effective in limiting organ injury in inflammatory vascular diseases.

Abnormal expression of PRKAG2-AS results in dysfunction of cardiomyocytes through regulating PRKAG2 transcription by interacting with PPARG.

The role of PRKAG2 in the maintenance of heart function is well established, but little is known about how PRKAG2 is regulated in cardiomyocytes. In this study, we investigated the role of the lncRNA PRKAG2-AS, which is present at the PRKAG2 promoter, in the regulation of PRKAG2 expression. PRKAG2-AS expression was predominantly nuclear, as determined by RNA nucleoplasmic separation and fluorescence in situ hybridization. Knockdown of PRKAG2-AS in the nucleus, but not the cytoplasm, significantly decreased the expression of PRKAG2b and PRKAG2d. Interestingly, we found that PRKAG2-AS and its target genes, PRKAG2b and PRKAG2d, were reduced in the hearts of patients with ischemic cardiomyopathy, suggesting a potential role for PRKAG2-AS in myocardial ischemia. Indeed, knockdown of PRKAG2-AS in the nucleus resulted in apoptosis of cardiomyocytes. We further elucidated the mechanism by which PRKAG2-AS regulates PRKAG2 transcription by identifying 58 PRKAG2-AS interacting proteins. Among them, PPARG was selected for further investigation based on its correlation and potential interaction with PRKAG2-AS in regulating transcription. Overexpression of PPARG, or its activation with rosiglitazone, led to a significant increase in the expression of PRKAG2b and PRKAG2d in cardiomyocytes, which could be attenuated by PRKAG2-AS knockdown. This finding suggests that PRKAG2-AS mediates, at least partially, the protective effects of rosiglitazone on hypoxia-induced apoptosis. However, given the risk of rosiglitazone in heart failure, we also examined the involvement of PRKAG2-AS in this condition and found that PRKAG2-AS, as well as PRKAG2b and PRKAG2d, was elevated in hearts with dilated cardiomyopathy (DCM) and that overexpression of PRKAG2-AS led to a significant increase in PRKAG2b and PRKAG2d expression, indicating that up-regulation of PRKAG2-AS may contribute to the mechanism of heart failure by promoting transcription of PRKAG2. Consequently, proper expression of PRKAG2-AS is essential for maintaining cardiomyocyte function, and aberrant PRKAG2-AS expression induced by hypoxia or other stimuli may cause cardiac dysfunction.

Signal transduction during cold, salt, and drought stresses in plants.

Abiotic stresses, especially cold, salinity and drought, are the primary causes of crop loss worldwide. Plant adaptation to environmental stresses is dependent upon the activation of cascades of molecular networks involved in stress perception, signal transduction, and the expression of specific stress-related genes and metabolites. Plants have stress-specific adaptive responses as well as responses which protect the plants from more than one environmental stress. There are multiple stress perception and signaling pathways, some of which are specific, but others may cross-talk at various steps. In this review article, we first expound the general stress signal transduction pathways, and then highlight various aspects of biotic stresses signal transduction networks. On the genetic analysis, many cold induced pathways are activated to protect plants from deleterious effects of cold stress, but till date, most studied pathway is ICE-CBF-COR signaling pathway. The Salt-Overly-Sensitive (SOS) pathway, identified through isolation and study of the sos1, sos2, and sos3 mutants, is essential for maintaining favorable ion ratios in the cytoplasm and for tolerance of salt stress. Both ABA-dependent and -independent signaling pathways appear to be involved in osmotic stress tolerance. ROS play a dual role in the response of plants to abiotic stresses functioning as toxic by-products of stress metabolism, as well as important signal transduction molecules and the ROS signaling networks can control growth, development, and stress response. Finally, we talk about the common regulatory system and cross-talk among biotic stresses, with particular emphasis on the MAPK cascades and the cross-talk between ABA signaling and biotic signaling.

An updated meta-analysis of device related thrombus following left atrial appendage closure in patients with atrial fibrillation.

Aims: Device related thrombus (DRT) is a known complication of left atrial appendage closure (LAAC). However, the relation between DRT and elevated risk of ischemic events remains controversial. This study is sought to reassessed the incidence of DRT following LAAC and the relation between DRT and elevated risk of ischemic stroke and systemic embolism (SE) with latest clinical trials included. Methods: The PubMed, Embase, and Cochrane Library databases were systematically searched from their inception until April 2022 for studies that reported the incidence of DRT and compared the incidence of both stroke and SE between DRT patients and non-DRT patients. Results: In 59 eligible studies, the incidence of DRT was 366/12,845 (2.8%, ranging from 0 to 11%, I 2 = 64%). The incidence of DRT was not statistically different between single-seal device (SS) and dual-seal device (DS) in subgroup analysis [171/6,190 (2.8%) vs. 78/3,023 (3.6%); p = 0.93]. The pooled incidence of stroke (26 studies, 7,827 patients) in patients with and without DRT was 11.5% in DRT patients and 2.9% among non-DRT patients (OR: 5.08; 95% CI = 3.47-7.44). In the sensitivity analysis, DRT was associated with higher rate of stroke (12.1 vs. 3.2%; OR: 4.14; 95% CI = 2.69-6.38) and SE (16.0 vs. 3.8%; OR: 4.48; 95% CI = 3.04-6.62). Conclusion: The incidence of DRT was low and similar between SS and DS devices. DRT was associated with increased rates of ischemic events. The occurrence rate of ischemic events associated DRT was comparable between two occlusion mechanism devices. Systematic review registration: [https://www.crd.york.ac.uk/], identifier [CRD42022326179].

Proangiogenesis effects of compound danshen dripping pills in zebrafish.

BACKGROUND: The compound Danshen Dripping Pill (CDDP), which is a mixture of extracts from Radix Salviae and Panax notoginseng, is a patented traditional Chinese medicine that is widely used in multiple countries for relieving coronary heart disease (CHD), but its pharmacological mechanism has not been fully elucidated. In this study, we screened the key pharmacological pathways and targets of CDDP that act on CHD using a network pharmacology-based strategy, and the angiogenic activity of CDDP was directly visually investigated in zebrafish embryos in vivo. METHODS: The potential therapeutic targets and pathways were predicted through a bioinformatics analysis. The proangiogenic effects of CDDP were examined using vascular sprouting assays on subintestinal vessels (SIVs) and optic arteries (OAs) as well as injury assays on intersegmental vessels (ISVs). Pharmacological experiments were applied to confirm the pathway involved. RESULTS: Sixty-five potential therapeutic targets of CDDP on CHD were identified and enriched in the PI3K/AKT and VEGF/VEGFR pathways. An in vivo study revealed that CDDP promoted angiogenesis in SIVs and OAs in a dose-dependent manner and relieved the impairments in ISVs induced by lenvatinib, a VEGF receptor kinase inhibitor (VRI). In addition, Vegfaa and Kdrl expression were significantly upregulated after CDDP treatment. Furthermore, the proangiogenic effect of CDDP could be abolished by PI3K/AKT pathway inhibitors. CONCLUSIONS: CDDP has a proangiogenic effect, the mechanism of which involves the VEGF/VEGFR and PI3K/AKT signaling pathways. These results suggest a new insight into the cardiovascular protective effect of CDDP.

Identification and characterization of AnICE1 and AnCBFs involved in cold tolerance from Ammopiptanthus nanus.

The ICE-CBF-COR pathway plays a vital role in improving the cold tolerance of plants. As an evergreen small shrub, Ammopiptanthus nanus has a high tolerance to cold stress because of its special growth conditions. Regrettably, no cold-responsive genes in the ICE-CBF-COR pathway have been reported in A. nanus. In the current study, we isolated AnICE1, AnCBF1, and AnCBF2 in A. nanus and analyzed their sequence structure. Evolutionary analysis indicated that these genes are most closely related to those from Ammopiptanthus mongolicus, Glycine max, Spatholobus suberectus, and Cajanus cajan, all belonging to the Fabaceae. Expression analysis showed that the expression levels of these genes were induced under cold stress and treatment with several plant hormones. As a critical upstream regulator in the ICE-CBF-COR pathway, the function of AnICE1 was further identified. The subcellular localization indicated that AnICE1 is predominantly localized in the plasma membrane and less in the nucleus. Overexpression of AnICE1 in Arabidopsis thaliana improved seed germination and growth of transgenic seedlings during cold stress. Moreover, some physiological indices such as relative electrical conductivity, contents of proline and malondialdehyde, catalase activity, and Nitro Blue tetrazolium and 3.3'-diaminobenzidine staining were investigated by transient expression in A. nanus seedlings and stable overexpression in A. thaliana. These results indicated that AnICE1 enhanced cold tolerance in A. nanus and transgenic A. thaliana. This study is significant for understanding the cold-resistant mechanism of ICE and CBF genes in A. nanus.