ABSTRACT
Diabetes mellitus (DM) is a progressive, chronic metabolic disorder characterized by high oxidative stress, which can lead to cardiac damage. Methionine sulfoxylation (MetO) of proteins by excessive reactive oxygen species (ROS) can impair the basic functionality of essential cellular proteins, contributing to heart failure. Methionine sulfoxide reductase B2 (MsrB2) can reverse oxidation induced MetO in mitochondrial proteins, so we investigated its role in diabetic cardiomyopathy. We observed that DM-induced heart damage in diabetic mice model is characterized by increased ROS, increased protein MetO with mitochondria structural pathology, and cardiac fibrosis. In addition, MsrB2 was significantly increased in mouse DM cardiomyocytes, supporting the induction of a protective process. Further, MsrB2 directly induces Parkin and LC3 activation (mitophagy markers) in cardiomyocytes. In MsrB2, knockout mice displayed abnormal electrophysiological function, as determined by ECG analysis. Histological analysis confirmed increased cardiac fibrosis and disrupted cardiac tissue in MsrB2 knockout DM mice. We then corroborated our findings in human DM heart samples. Our study demonstrates that increased MsrB2 expression in the heart protects against diabetic cardiomyopathy.
ABSTRACT
Loss-of-function mutations in methyl-CpG binding protein 2 ( MECP2 ) cause Rett syndrome, a postnatal neurodevelopmental disorder that occurs in â¼1/10,000 live female births. MeCP2 binds to methylated cytosines across genomic DNA and recruits various partners to regulate gene expression. MeCP2 has been shown to repress transcription in vitro and interacts with co-repressors such as the Sin3A and NCoR complexes. Based on these observations, MeCP2 has been largely considered as a repressor of transcription. However, a mouse model of RTT displays many down-regulated genes, and those same genes are up-regulated in a MECP2 duplication mouse model. Furthermore, TCF20, which has been associated with transcriptional activation, have recently been identified as a protein interactor of MeCP2. These data broaden the potential functions of MeCP2 as a regulator of gene expression. Yet, the molecular mechanisms underlying MeCP2-dependent gene regulation remain largely unknown. Here, using a human MECP2 gain-of-function Drosophila model, we screened for genetic modifiers of MECP2 -induced phenotypes. Our approach identified several subunits of the Drosophila super elongation complex, a P-TEFb containing RNA polymerase II (RNA pol II) elongation factor required for the release of promoter-proximally paused RNA pol II, as genetic interactors of MECP2 . We discovered that MeCP2 physically interacts with the SEC in human cells and in the mouse brain. Furthermore, we found that MeCP2 directly binds AFF4, the scaffold of the SEC, via the transcriptional repression domain. Finally, loss of MeCP2 in the mouse cortex caused reduced binding of AFF4 specifically on a subset of genes involved in the regulation of synaptic function, which also displayed the strongest decrease in RNA pol II binding in the genebody. Taken together, our study reveals a previously unrecognized mechanism through which MeCP2 regulates transcription, providing a new dimension to its regulatory role in gene expression.
ABSTRACT
Importance: P2Y12 inhibitor monotherapy after dual antiplatelet therapy (DAPT; a P2Y12 inhibitor plus aspirin) for a brief duration has recently emerged as an attractive alternative for patients undergoing percutaneous coronary intervention (PCI) with a drug-eluting stent. Objective: To investigate whether P2Y12 inhibitor monotherapy after 3 months of DAPT was noninferior to 12 months of DAPT following PCI with a drug-eluting stent. Design, Setting, and Participants: The Short-Term Dual Antiplatelet Therapy After Deployment of Bioabsorbable Polymer Everolimus-Eluting Stent (SHARE) open-label, noninferiority randomized clinical trial was conducted from December 15, 2017, through December 14, 2020. Final 1-year clinical follow-up was completed in January 2022. This study was a multicenter trial that was conducted at 20 hospitals in South Korea. Patients who underwent successful PCI with bioabsorbable polymer everolimus-eluting stents were enrolled. Interventions: Patients were randomly assigned to receive P2Y12 inhibitor monotherapy after 3 months of DAPT (n = 694) or 12 months of DAPT (n = 693). Main Outcomes and Measures: The primary outcome was a net adverse clinical event, a composite of major bleeding (based on Bleeding Academic Research Consortium type 3 or type 5 bleeding) and major adverse cardiac and cerebrovascular events (cardiac death, myocardial infarction, stent thrombosis, stroke, or ischemia-driven target lesion revascularization) between 3 and 12 months after the index PCI. The major secondary outcomes were major adverse cardiac and cerebrovascular events and major bleeding. The noninferiority margin was 3.0%. Results: Of the total 1452 eligible patients, 65 patients were excluded before the 3-month follow-up, and 1387 patients (mean [SD] age, 63.0 [10.7] years; 1055 men [76.1%]) were assigned to P2Y12 inhibitor monotherapy (n = 694) or DAPT (n = 693). Between 3 and 12 months of follow-up, the primary outcome (using Kaplan-Meier estimates) occurred in 9 patients (1.7%) in the P2Y12 inhibitor monotherapy group and in 16 patients (2.6%) in the DAPT group (absolute difference, -0.93 [1-sided 95% CI, -2.64 to 0.77] percentage points; P < .001 for noninferiority). For the major secondary outcomes (using Kaplan-Meier estimates), major adverse cardiac and cerebrovascular events occurred in 8 patients (1.5%) in the P2Y12 inhibitor monotherapy group and in 12 patients (2.0%) in the DAPT group (absolute difference, -0.49 [95% CI, -2.07 to 1.09] percentage points; P = .54). Major bleeding occurred in 1 patient (0.2%) in the P2Y12 inhibitor monotherapy group and in 5 patients (0.8%) in the DAPT group (absolute difference, -0.60 [95% CI, -1.33 to 0.12] percentage points; P = .10). Conclusions and Relevance: In patients with coronary artery disease undergoing PCI with the latest generation of drug-eluting stents, P2Y12 inhibitor monotherapy after 3-month DAPT was not inferior to 12-month DAPT for net adverse clinical events. Considering the study population and lower-than-expected event rates, further research is required in other populations. Trial Registration: ClinicalTrials.gov Identifier: NCT03447379.
Subject(s)
Drug-Eluting Stents , Percutaneous Coronary Intervention , Male , Humans , Middle Aged , Platelet Aggregation Inhibitors/therapeutic use , Everolimus/therapeutic use , Hemorrhage/chemically induced , Hemorrhage/epidemiology , PolymersABSTRACT
Hypoxia-inducible factor-1 alpha (HIF-1α) is a regulatory factor of intracellular oxygen supersession. The expression or increased activity of HIF-1α is closely related to various human cancers. Previously, IDF-11774 was demonstrated to inhibit HSP70 chaperone activity and suppress the accumulation of HIF-1α. In this study, we aimed to determine the effects of IDF-11774 on gastric cancer cell lines. Treatment with IDF-11774 was found to markedly decrease the proliferation, migration, and invasion of the gastric cancer cell lines. Furthermore, the phosphorylation levels of extracellular signal-regulated kinase 1/2, p38, and Jun N-terminal kinase in the mitogen-activated protein kinase signaling pathways were markedly increased in a dose-dependent manner, ultimately promoting apoptosis via the induction of cell cycle arrest. Our findings indicate that HIF-1α inhibitors are potent drugs for the treatment of gastric cancer.
ABSTRACT
Air pollution is an environmental risk factor linked to multiple human diseases including cardiovascular diseases (CVDs). While particulate matter (PM) emitted by diesel exhaust damages multiple organ systems, heart disease is one of the most severe pathologies affected by PM. However, the in vivo effects of diesel exhaust particles (DEP) on the heart and the molecular mechanisms of DEP-induced heart dysfunction have not been investigated. In the current study, we attempted to identify the proteomic signatures of heart fibrosis caused by diesel exhaust particles (DEP) in CVDs-prone apolipoprotein E knockout (ApoE-/-) mice model using tandem mass tag (TMT)-based quantitative proteomic analysis. DEP exposure induced mild heart fibrosis in ApoE-/- mice compared with severe heart fibrosis in ApoE-/- mice that were treated with CVDs-inducing peptide, angiotensin II. TMT-based quantitative proteomic analysis of heart tissues between PBS- and DEP-treated ApoE-/- mice revealed significant upregulation of proteins associated with platelet activation and TGFß-dependent pathways. Our data suggest that DEP exposure could induce heart fibrosis, potentially via platelet-related pathways and TGFß induction, causing cardiac fibrosis and dysfunction.
Subject(s)
Cardiovascular Diseases , Vehicle Emissions , Animals , Humans , Mice , Apolipoproteins E/genetics , Cardiovascular Diseases/etiology , Fibrosis , Particulate Matter/toxicity , Proteomics , Transforming Growth Factor beta , Vehicle Emissions/toxicityABSTRACT
Spontaneous celiac artery dissection caused by fibromuscular dysplasia is rare. Subsequent thrombosis and occlusion of the celiac trunk can result in intestinal ischemia and hepatic failure. We describe a case of spontaneous celiac artery dissection with an associated pseudoaneurysm caused by fibromuscular dysplasia, extending into the common hepatic artery. An endovascular intervention featuring robotic-assisted celiac artery cannulation with stent-assisted coil embolization resulted in successful treatment.