Adaptor protein Src-homology 2 domain containing E (SH2E) deficiency induces heart defect in zebrafish.

Adaptor proteins play crucial roles in signal transduction across diverse signaling pathways. Src-homology 2 domain-containing E (SH2E) is the adaptor protein highly expressed in vascular endothelial cells and myocardium during zebrafish embryogenesis. In this study we investigated the function and mechanisms of SH2E in cardiogenesis. We first analyzed the spatiotemporal expression of SH2E and then constructed zebrafish lines with SH2E deficiency using the CRISPR-Cas9 system. We showed that homozygous mutants developed progressive pericardial edema (PCE), dilated atrium, abnormal atrioventricular looping and thickened atrioventricular wall from 3 days post fertilization (dpf) until death; inducible overexpression of SH2E was able to partially rescue the PCE phenotype. Using transcriptome sequencing analysis, we demonstrated that the MAPK/ERK and NF-κB signaling pathways might be involved in SH2E-deficiency-caused PCE. This study underscores the pivotal role of SH2E in cardiogenesis, and might help to identify innovative diagnostic techniques and therapeutic strategies for congenital heart disease.

Inhibiting endothelial cell Mst1 attenuates acute lung injury in mice.

Lung endothelium plays a pivotal role in the orchestration of inflammatory responses to acute pulmonary insults. Mammalian sterile 20-like kinase 1 (Mst1) is a serine/threonine kinase that has been shown to play an important role in the regulation of apoptosis, stress responses, and organ growth. This study investigated the role of Mst1 in lung endothelial activation and acute lung injury (ALI). We found that Mst1 was significantly activated in inflamed lung endothelial cells (ECs) and mouse lung tissues. Overexpression of Mst1 promoted nuclear factor κ-B (NF-κB) activation through promoting JNK and p38 activation in lung ECs. Inhibition of Mst1 by either its dominant negative form (DN-Mst1) or its pharmacological inhibitor markedly attenuated cytokine-induced expression of cytokines, chemokines, and adhesion molecules in lung ECs. Importantly, in a mouse model of lipopolysaccharide-induced (LPS-induced) ALI, both deletion of Mst1 in lung endothelium and treatment of WT mice with a pharmacological Mst1 inhibitor significantly protected mice from LPS-induced ALI. Together, our findings identified Mst1 kinase as a key regulator in controlling lung EC activation and suggest that therapeutic strategies aimed at inhibiting Mst1 activation might be effective in the prevention and treatment of inflammatory lung diseases.

Animal Experimental Study of Bioabsorbable Left Atrial Appendage Occluder.

Left atrial appendage (LAA) closure can prevent stroke in high-risk patients with atrial fibrillation.A bioabsorbable LAA occluder made of degradable polymer materials, such as polydioxanone (PDO) and poly-L-lactic acid (PLA), and nitinol wire was used. Occluders were successfully implanted in 18 Chinese rural dogs, 2 of which died within 48 hours after operation due to pericardial tamponade and hemorrhage, respectively. Follow-up observation was performed after transcatheter LAA closure. New tissue was found on the surface of the occluder 2 months after operation. No adjacent structures such as the mitral valve and the left superior pulmonary vein were affected by the occluder discs. Hematoxylin and eosin (HE) staining was performed at 3 months after operation, which showed intact intimal structure on the occluder surface, and unabsorbed PDO and PLA were observed. Scanning electron microscopy showed irregular arrangement of endothelial cells. New endothelial tissue was observed to completely cover the occluder at 6 months after operation. Most PDOs were replaced by fibrous connective tissue, and scanning electron microscopy showed regularly arranged endothelial cells. Pathological examination at 12 months showed only a small remnant of PDO. The gross specimens of the liver, spleen, and kidneys and pathological examination did not indicate thromboembolism.The bioabsorbable LAA occluder made of PDO, PLA, and nitinol wire was safe and effective for the occlusion of LAA in dogs. The surface of the occluder was endothelialized half a year after operation. The absorbable materials of the occluder were degraded after 1 year.

Identification of alternative splicing regulatory patterns and characteristic splicing factors in heart failure using RNA-seq data and machine learning.

Heart failure (HF) represents the advanced stage of several cardiovascular disorders. This study aimed to build an alternative splicing regulatory network and identify potential splicing factors involved in HF utilizing RNA-seq data and machine learning algorithms. We performed bioinformatics analysis on RNA-seq datasets containing samples from HF patients and normal individuals to obtain gene expression matrices and identify differently regulated alternative splicing events in HF. By calculating percent spliced-in (PSI) value, we identified 4055 abnormal alternative splicing events of 3142 genes in HF. These genes were significantly enriched in PPAR signaling, regulation of actin cytoskeleton, and muscle contraction. Interestingly, based on abnormal alternative splicing events, two distinct clusters of HF patients with distinct molecular mechanisms and pathways were identified using unsupervised clustering. Additionally, we built a regulatory network consisting of heart failure-related alternative splicing and splicing factors. Subsequently, we identify 203 HF specific pairs between splicing factors and alternative splicing events. Four splicing factors (RBM5, ZRANB2, HnRNPF, and HnRNPA0) were found using LASSO and SVM-RFE algorithms, their expression patterns were confirmed in two other microarray datasets. Our study clarifies involvement of splicing factors and alternative splicing events in HF by thoroughly analyzing RNA-seq data with machine learning methods. The findings may advance our understanding of the regulatory systems underlying biological processes associated with heart failure by providing candidates for further investigation and markers for diagnostic and therapeutic purposes.

Niclosamide modulates phenotypic switch and inflammatory responses in human pulmonary arterial smooth muscle cells.

Excessive proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs) represent key steps of pulmonary vascular remodeling, leading to the development of pulmonary arterial hypertension (PAH) and right ventricular failure. Niclosamide (NCL), an FDA-approved anthelmintic, has been shown to regulate cell proliferation, migration, invasion, and apoptosis through a variety of signaling pathways. However, its role on modulating the phenotypic switch and inflammatory responses in PASMCs remains unclear. In this study, cell proliferation assay showed that NCL inhibited PDGF-BB induced proliferation of human PASMCs in a dose-dependent manner. Western blot analysis further confirmed a notable reduction in the expression of cyclin D1 and PCNA proteins. Subsequently, flow cytometry analysis demonstrated that NCL induced an increased percentage of cells in the G1 phase while promoting apoptosis in PASMCs. Moreover, both scratch wound assay and transwell assay confirmed that NCL decreased PDGF-BB-induced migration of PASMCs. Mechanistically, western blot revealed that pretreatment of PASMCs with NCL markedly restored the protein levels of SMA, SM22, and calponin, while reducing phosphorylation of P38/STAT3 signaling in the presence of PDGF-BB. Interestingly, macrophages adhesion assay showed that NCL markedly reduced recruitment of Calcein-AM labeled RAW264.7 by TNFα-stimulated PASMCs. Western blot revealed that NCL suppressed TNFα-induced expression of both of VCAM-1 and ICAM-1 proteins. Furthermore, pretreatment of PASMCs with NCL significantly inhibited NLRP3 inflammasome activity through reducing NLRP3, AIM2, mature interleukin-1ß (IL-ß), and cleaved Caspase-1 proteins expression. Together, these results suggested versatile effects of NCL on controlling of proliferation, migration, and inflammatory responses in PASMCs through modulating different pathways, indicating that repurposing of NCL may emerge as a highly effective drug for PAH treatment.

Insufficient Ablation is Associated with Atrial Fibrillation Recurrence after Combining Ablation and Left Atrial Appendage Closure.

Background: The combination of left atrial appendage closure (LAAC) and catheter ablation (CA) in a single procedure is a safe and effective form of treatment for atrial fibrillation (AF). However, several findings have argued that LAAC might increase the risk of AF recurring. Therefore, this study investigated the impact of insufficient ablation on AF recurrence after the hybrid procedures of CA and LAAC. Methods: We reviewed 107 consecutive patients with AF who received the CA and LAAC hybrid procedures (combined group). In the case-control study, another 107 patients who underwent only CA (ablation group) were successfully matched using propensity score matching. After correcting the insufficient ablation, 107 consecutive patients were enrolled prospectively. During the follow-up period, postprocedural 24-hour monitor recordings and a portable electrocardiogram (ECG) monitoring device were used to detect AF recurrence. Transesophageal echocardiography was used to evaluate LAAC. Results: The combined group showed an increase in the risk of AF recurrence after 539.2 ± 304.4 days of follow-up (29.9% vs. 15.9%, p < 0.05). Interestingly, the duration of the procedure was not significantly prolonged when LAAC was added after CA in the combined group, while there was a higher number of ablating attempts, duration of ablation, and additional ablation in the ablation group for both radiofrequency and cryoballoon ablation. After correcting for the insufficient ablation, the corrected group showed a significant decrease in AF recurrence after 420.4 ± 204.8 days of follow-up. Conclusions: Insufficient ablation is common when combining CA and LAAC and may lead to the recurrence of atrial fibrillation. It should be corrected intentionally by sufficient ablation of the pulmonary vein antrum and additional ablation. Clinical Trial Registration: The prospective study is a sub-study of our CAGEDAF study that has already been registered (ChiCTR2000039746).

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.

Safety and efficacy of the second-generation cryoballoon for left atrial appendage electrical isolation in canines.

AIMS: Left atrial appendage electrical isolation (LAAEI) has demonstrated a significant enhancement in the success rate of atrial fibrillation (AF) ablation. Nevertheless, concerns persist about the safety of LAAEI, particularly regarding alterations in left atrial appendage (LAA) flow velocity and the potential risks of thrombus. This study aimed to assess the efficacy and safety of LAAEI, investigating changes in LAA flow velocity in canines. METHODS AND RESULTS: The study comprised a total of 10 canines. The LAAEI procedure used by a 23 mm cryoballoon of the second generation was conducted at least 180 s. Intracardiac ultrasonography (ICE) was employed to quantify the velocity flow of the LAA both prior to and following LAAEI. Following a 3-month period, subsequent evaluations were performed to assess the LAA velocity flow and the potential reconnection. Histopathological examination was conducted. Left atrial appendage electrical isolation was effectively accomplished in all canines, resulting in a 100% acute success rate (10/10). The flow velocity in the LAA showed a notable reduction during LAAEI as compared with the values before the ablation procedure (53.12 ± 5.89 vs. 42.01 ± 9.22 cm/s, P = 0.007). After the follow-up, reconnection was observed in four canines, leading to a success rate of LAAEI of 60% (6/10). The flow velocity in the LAA was consistently lower (53.12 ± 5.89 vs. 44.33 ± 10.49 cm/s, P = 0.006), and no blood clot development was observed. The histopathological study indicated that there was consistent and complete injury to the LAA, affecting all layers of its wall. The injured tissue was subsequently replaced by fibrous tissue. CONCLUSION: The feasibility of using cryoballoon ablation for LAAEI was confirmed in canines, leading to a significant reduction of LAA flow velocity after ablation. Some restoration of LAA flow velocity after ablation may be linked to the passive movement of the LAA and potential reconnecting. However, this conclusion is limited to animal study; more clinical data are needed to further illustrate the safety and accessibility of LAAEI in humans.

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.

Regulatory mechanisms of long non-coding RNAs on mitochondrial function in congestive heart failure.

Congestive heart failure (CHF) is a multifaceted cardiovascular condition that imposes significant economic and social burdens on society, while also presenting a dearth of efficacious treatment modalities. Long non-coding RNAs (lncRNAs) possess the ability to influence the pathophysiological mechanisms underlying cardiac disease through their regulation of gene transcription, translation, and post-translational modifications. Additionally, certain lncRNAs can be encoded by the mitochondrial genome, hence impacting mitochondrial function. The heart relies heavily on mitochondrial oxidative phosphorylation for approximately 95 % of its ATP production. Consequently, the primary determinant linking mitochondrial dysfunction to heart failure is the impairment of cardiac energy supply resulting from mitochondrial injury. Cardiac dysfunction can arise as a result of various factors, including metabolic disease, disturbances in calcium homeostasis, oxidative stress, apoptosis, and mitochondrial phagocytosis, all of which are facilitated by mitochondrial damage. Currently, an increasing body of research indicates that lncRNA plays a significant role in the regulation of mitochondrial activity, hence impacting heart failure. As a result, the goal of this paper is to propose new ideas and targets for clinical research and therapy of heart failure by reviewing recent research on the regulatory mechanism of mitochondrial function by novel lncRNAs.

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.

Wide QRS complex tachycardia with a mysterious mask-Tricuspid isthmus-dependent atrial flutter with preexcitation syndrome and dual atrioventricular nodal pathway conduction.

Key Clinical Message: Atrial flutter (AFL) and supraventricular tachycardia (SVT) are common arrhythmias in clinic. However, some AFL cases may present additional complexities, such as both accessory pathways (AP) and dual atrioventricular node pathways, putting on a mysterious mask and making it challenging to distinguish on electrocardiograms (ECGs). Abstract: A 60-year-old male patient had a sudden syncope, and an ECG showed wide QRS complex tachycardia. This diagnostic ambiguity is further compounded by the fact that SVT via AP conduction can exhibit wide QRS complex tachycardia characteristics resembling ventricular tachycardia (VT). Consequently, a definitive diagnosis through electrophysiological (EP) examination becomes imperative, as it dictates subsequent ablation strategies. In this article, we present a rare case involving three distinct arrhythmias including AFL, AP, and dual atrioventricular node pathways, and successfully treated through ablation.

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.

Zero x-rays radiofrequency catheter ablation for ventricular premature contraction originating from the left coronary cusp during pregnancy: a case report.

Pregnancy predisposes to arrhythmias in females due to physiological changes in the cardiovascular system, enhanced activity of the sympathetic nervous system (SNS), and changes in the endocrine system, regardless of whether there exist cardiovascular diseases before the pregnancy. Tachyarrhythmias may present for the first time or worsen persistently during pregnancy, potentially leading to maternal heart failure and sudden death, as well as some adverse fetal outcomes such as growth restriction, distress, premature birth, and stillbirth. Radiofrequency ablation (RFA) is one of the most important therapeutic methods for tachyarrhythmias. According to the 2019 European Society of Cardiology (ESC) guidelines, RFA in pregnant women should preferably be performed without x-rays. Since the 2000s, 3D mapping technique has rapidly developed, laying the foundation for cardiac electrophysiology examination free from x-rays. Ventricular arrhythmia originating from the left coronary cusp (LCC) is not common in clinic. RFA is challenging in the treatment of this type of disease due to the anatomical feature that the opening of the left main coronary artery is localized in the LCC.

Identifying potential biological processes and key targets in COVID-19-associated heart failure.

Novel coronavirus pneumonia (COVID-19) is a new type of viral pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that has spread rapidly and become a global pandemic. Heart failure (HF) is the ultimate period of the development of various cardiovascular diseases. There are several research have found that SARS-CoV-2 infection may induce cardiac complications including enhanced cardiac stress biomarkers and heart failure. Our research aims at identifying underlying biological processes and key targets in COVID-19-associated heart failure via bioinformatics analysis. A total of three heart failure datasets and three COVID-19 datasets were obtained using the Gene Expression Omnibus (GEO) database. Batch effects cross each sample were eliminated with surrogate variable analysis algorithm. Then, we identified key modules of COVID-19 datasets and heart failure datasets through weighted gene co-expression network analysis. HF-associated as well as COVID-19-associated key modules were intersected for determining the shared genes of COVID-19-associated heart failure. The pivotal genes associated with COVID-19-related heart failure were determined by intersecting the shared genes with the HF-associated hub genes selected through WGCNA. Furthermore, we conducted GO as well as KEGG enrichment analysis on shared genes of COVID-19-associated heart failure. Two COVID-19-associated key modules as well as three HF-associated key modules were determined. In addition, eleven shared genes for COVID-19-associated heart failure were determined. In conclusion, our work screened two critical genes, namely PYGM and BLM, which may be possible intervention targets for COVID-19-associated heart failure. According to functional enrichment results, the shared genes of COVID-19-associated heart failure showed high enrichment in starch and sucrose metabolism, homologous recombination, Fanconi anemia pathway, and insulin resistance indicate the probably biological processes linked to COVID-19-associated heart failure. These results provided further insights in possible interventional and therapeutic targets of COVID-19-associated heart failure.

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.

Natural variation in OsSEC13 HOMOLOG 1 modulates redox homeostasis to confer cold tolerance in rice.

Rice (Oryza sativa L.) is a cold-sensitive species that often faces cold stress, which adversely affects yield productivity and quality. However, the genetic basis for low-temperature adaptation in rice remains unclear. Here, we demonstrate that 2 functional polymorphisms in O. sativa SEC13 Homolog 1 (OsSEH1), encoding a WD40-repeat nucleoporin, between the 2 subspecies O. sativa japonica and O. sativa indica rice, may have facilitated cold adaptation in japonica rice. We show that OsSEH1 of the japonica variety expressed in OsSEH1MSD plants (transgenic line overexpressing the OsSEH1 allele from Mangshuidao [MSD], cold-tolerant landrace) has a higher affinity for O. sativa metallothionein 2b (OsMT2b) than that of OsSEH1 of indica. This high affinity of OsSEH1MSD for OsMT2b results in inhibition of OsMT2b degradation, with decreased accumulation of reactive oxygen species and increased cold tolerance. Transcriptome analysis indicates that OsSEH1 positively regulates the expression of the genes encoding dehydration-responsive element-binding transcription factors, i.e. OsDREB1 genes, and induces the expression of multiple cold-regulated genes to enhance cold tolerance. Our findings highlight a breeding resource for improving cold tolerance in rice.