ABSTRACT
BACKGROUND: Clearance of damaged mitochondria via mitophagy is crucial for cellular homeostasis. Apart from Parkin, little is known about additional Ub (ubiquitin) ligases that mediate mitochondrial ubiquitination and turnover, particularly in highly metabolically active organs such as the heart. METHODS: In this study, we have combined in silico analysis and biochemical assay to identify CRL (cullin-RING ligase) 5 as a mitochondrial Ub ligase. We generated cardiomyocytes and mice lacking RBX2 (RING-box protein 2; also known as SAG [sensitive to apoptosis gene]), a catalytic subunit of CRL5, to understand the effects of RBX2 depletion on mitochondrial ubiquitination, mitophagy, and cardiac function. We also performed proteomics analysis and RNA-sequencing analysis to define the impact of loss of RBX2 on the proteome and transcriptome. RESULTS: RBX2 and CUL (cullin) 5, 2 core components of CRL5, localize to mitochondria. Depletion of RBX2 inhibited mitochondrial ubiquitination and turnover, impaired mitochondrial membrane potential and respiration, increased cardiomyocyte cell death, and has a global impact on the mitochondrial proteome. In vivo, deletion of the Rbx2 gene in adult mouse hearts suppressed mitophagic activity, provoked accumulation of damaged mitochondria in the myocardium, and disrupted myocardial metabolism, leading to the rapid development of dilated cardiomyopathy and heart failure. Similarly, ablation of RBX2 in the developing heart resulted in dilated cardiomyopathy and heart failure. The action of RBX2 in mitochondria is not dependent on Parkin, and Parkin gene deletion had no impact on the onset and progression of cardiomyopathy in RBX2-deficient hearts. Furthermore, RBX2 controls the stability of PINK1 (PTEN-induced kinase 1) in mitochondria. CONCLUSIONS: These findings identify RBX2-CRL5 as a mitochondrial Ub ligase that regulates mitophagy and cardiac homeostasis in a Parkin-independent, PINK1-dependent manner.
Subject(s)
Mice, Knockout , Mitochondria, Heart , Mitophagy , Myocytes, Cardiac , Ubiquitination , Animals , Humans , Male , Mice , Cells, Cultured , Mice, Inbred C57BL , Mitochondria, Heart/metabolism , Mitochondria, Heart/enzymology , Mitochondria, Heart/genetics , Mitochondria, Heart/pathology , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/geneticsABSTRACT
The monomer-binding protein profilin 1 (PFN1) plays a crucial role in actin polymerization. However, mutations in PFN1 are also linked to hereditary amyotrophic lateral sclerosis, resulting in a broad range of cellular pathologies which cannot be explained by its primary function as a cytosolic actin assembly factor. This implies that there are important, undiscovered roles for PFN1 in cellular physiology. Here we screened knockout cells for novel phenotypes associated with PFN1 loss of function and discovered that mitophagy was significantly upregulated. Indeed, despite successful autophagosome formation, fusion with the lysosome, and activation of additional mitochondrial quality control pathways, PFN1 knockout cells accumulate depolarized, dysmorphic mitochondria with altered metabolic properties. Surprisingly, we also discovered that PFN1 is present inside mitochondria and provide evidence that mitochondrial defects associated with PFN1 loss are not caused by reduced actin polymerization in the cytosol. These findings suggest a previously unrecognized role for PFN1 in maintaining mitochondrial integrity and highlight new pathogenic mechanisms that can result from PFN1 dysregulation.
Subject(s)
Actins , Mitochondria , Profilins , Profilins/metabolism , Profilins/genetics , Mitochondria/metabolism , Mitochondria/genetics , Humans , Actins/metabolism , Mitophagy/genetics , Lysosomes/metabolism , Cytosol/metabolism , Gene Knockout Techniques , Autophagosomes/metabolism , HeLa CellsABSTRACT
BACKGROUND: Pulmonary arterial hypertension (PAH) is high blood pressure in the lungs that originates from structural changes in small resistance arteries. A defining feature of PAH is the inappropriate remodeling of pulmonary arteries (PA) leading to right ventricle failure and death. Although treatment of PAH has improved, the long-term prognosis for patients remains poor, and more effective targets are needed. METHODS: Gene expression was analyzed by microarray, RNA sequencing, quantitative polymerase chain reaction, Western blotting, and immunostaining of lung and isolated PA in multiple mouse and rat models of pulmonary hypertension (PH) and human PAH. PH was assessed by digital ultrasound, hemodynamic measurements, and morphometry. RESULTS: Microarray analysis of the transcriptome of hypertensive rat PA identified a novel candidate, PBK (PDZ-binding kinase), that was upregulated in multiple models and species including humans. PBK is a serine/threonine kinase with important roles in cell proliferation that is minimally expressed in normal tissues but significantly increased in highly proliferative tissues. PBK was robustly upregulated in the medial layer of PA, where it overlaps with markers of smooth muscle cells. Gain-of-function approaches show that active forms of PBK increase PA smooth muscle cell proliferation, whereas silencing PBK, dominant negative PBK, and pharmacological inhibitors of PBK all reduce proliferation. Pharmacological inhibitors of PBK were effective in PH reversal strategies in both mouse and rat models, providing translational significance. In a complementary genetic approach, PBK was knocked out in rats using CRISPR/Cas9 editing, and loss of PBK prevented the development of PH. We found that PBK bound to PRC1 (protein regulator of cytokinesis 1) in PA smooth muscle cells and that multiple genes involved in cytokinesis were upregulated in experimental models of PH and human PAH. Active PBK increased PRC1 phosphorylation and supported cytokinesis in PA smooth muscle cells, whereas silencing or dominant negative PBK reduced cytokinesis and the number of cells in the G2/M phase of the cell cycle. CONCLUSIONS: PBK is a newly described target for PAH that is upregulated in proliferating PA smooth muscle cells, where it contributes to proliferation through changes in cytokinesis and cell cycle dynamics to promote medial thickening, fibrosis, increased PA resistance, elevated right ventricular systolic pressure, right ventricular remodeling, and PH.
Subject(s)
Pulmonary Arterial Hypertension , Pulmonary Artery , Vascular Remodeling , Animals , Humans , Rats , Mice , Male , Pulmonary Arterial Hypertension/metabolism , Pulmonary Arterial Hypertension/genetics , Pulmonary Arterial Hypertension/physiopathology , Pulmonary Arterial Hypertension/pathology , Pulmonary Artery/metabolism , Pulmonary Artery/pathology , Pulmonary Artery/physiopathology , Disease Models, Animal , Rats, Sprague-Dawley , Cell Proliferation , Mice, Inbred C57BL , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Mitogen-Activated Protein Kinase KinasesABSTRACT
BACKGROUND: Activation of vascular smooth muscle cell (VSMC) inflammation is vital to initiate vascular disease. The role of human-specific long noncoding RNAs in VSMC inflammation is poorly understood. METHODS: Bulk RNA sequencing in differentiated human VSMCs revealed a novel human-specific long noncoding RNA called inflammatory MKL1 (megakaryoblastic leukemia 1) interacting long noncoding RNA (INKILN). INKILN expression was assessed in multiple in vitro and ex vivo models of VSMC phenotypic modulation as well as human atherosclerosis and abdominal aortic aneurysm. The transcriptional regulation of INKILN was verified through luciferase reporter and chromatin immunoprecipitation assays. Loss-of-function and gain-of-function studies and multiple RNA-protein and protein-protein interaction assays were used to uncover a mechanistic role of INKILN in the VSMC proinflammatory gene program. Bacterial artificial chromosome transgenic mice were used to study INKILN expression and function in ligation injury-induced neointimal formation. RESULTS: INKILN expression is downregulated in contractile VSMCs and induced in human atherosclerosis and abdominal aortic aneurysm. INKILN is transcriptionally activated by the p65 pathway, partially through a predicted NF-κB (nuclear factor kappa B) site within its proximal promoter. INKILN activates proinflammatory gene expression in cultured human VSMCs and ex vivo cultured vessels. INKILN physically interacts with and stabilizes MKL1, a key activator of VSMC inflammation through the p65/NF-κB pathway. INKILN depletion blocks interleukin-1ß-induced nuclear localization of both p65 and MKL1. Knockdown of INKILN abolishes the physical interaction between p65 and MKL1 and the luciferase activity of an NF-κB reporter. Furthermore, INKILN knockdown enhances MKL1 ubiquitination through reduced physical interaction with the deubiquitinating enzyme USP10 (ubiquitin-specific peptidase 10). INKILN is induced in injured carotid arteries and exacerbates ligation injury-induced neointimal formation in bacterial artificial chromosome transgenic mice. CONCLUSIONS: These findings elucidate an important pathway of VSMC inflammation involving an INKILN/MKL1/USP10 regulatory axis. Human bacterial artificial chromosome transgenic mice offer a novel and physiologically relevant approach for investigating human-specific long noncoding RNAs under vascular disease conditions.
Subject(s)
Aortic Aneurysm, Abdominal , RNA, Long Noncoding , Animals , Humans , Mice , Aortic Aneurysm, Abdominal/metabolism , Cell Proliferation , Cells, Cultured , Inflammation/genetics , Inflammation/metabolism , Luciferases/metabolism , Mice, Transgenic , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , NF-kappa B/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Ubiquitin Thiolesterase/metabolismABSTRACT
Acylglycerophosphate acyltransferases (AGPATs) catalyze the de novo formation of phosphatidic acid to synthesize glycerophospholipids and triglycerides. AGPATs demonstrate unique physiological roles despite a similar biochemical function. AGPAT3 is highly expressed in the testis, kidney, and liver, with intermediate expression in adipose tissue. Loss of AGPAT3 is associated with reproductive abnormalities and visual dysfunction. However, the role of AGPAT3 in adipose tissue and whole body metabolism has not been investigated. We found that male Agpat3 knockout (KO) mice exhibited reduced body weights with decreased white and brown adipose tissue mass. Such changes were less pronounced in the female Agpat3-KO mice. Agpat3-KO mice have reduced plasma insulin growth factor 1 (IGF1) and insulin levels and diminished circulating lipid metabolites. They manifested intact glucose homeostasis and insulin sensitivity despite a lean phenotype. Agpat3-KO mice maintained an energy balance with normal food intake, energy expenditure, and physical activity, except for increased water intake. Their adaptive thermogenesis was also normal despite reduced brown adipose mass and triglyceride content. Mechanistically, Agpat3 was elevated during mouse and human adipogenesis and enriched in adipocytes. Agpat3-knockdown 3T3-L1 cells and Agpat3-deficient mouse embryonic fibroblasts (MEFs) have impaired adipogenesis in vitro. Interestingly, pioglitazone treatment rescued the adipogenic deficiency in Agpat3-deficient cells. We conclude that AGPAT3 regulates adipogenesis and adipose development. It is possible that adipogenic impairment in Agpat3-deficient cells potentially leads to reduced adipose mass. Findings from this work support the unique role of AGPAT3 in adipose tissue.NEW & NOTEWORTHY AGPAT3 deficiency results in male-specific growth retardation. It reduces adipose tissue mass but does not significantly impact glucose homeostasis or energy balance, except for influencing water intake in mice. Like AGPAT2, AGPAT3 is upregulated during adipogenesis, potentially by peroxisome proliferator-activated receptor gamma (PPARγ). Loss of AGPAT3 impairs adipocyte differentiation, which could be rescued by pioglitazone. Overall, AGPAT3 plays a significant role in regulating adipose tissue mass, partially involving its influence on adipocyte differentiation.
Subject(s)
1-Acylglycerol-3-Phosphate O-Acyltransferase , Adipocytes , Mice, Knockout , Animals , Female , Male , Mice , 1-Acylglycerol-3-Phosphate O-Acyltransferase/genetics , 1-Acylglycerol-3-Phosphate O-Acyltransferase/metabolism , Adipocytes/metabolism , Adipogenesis/genetics , Adipogenesis/physiology , Adipose Tissue, Brown/metabolism , Cell Differentiation , Energy Metabolism/genetics , Insulin Resistance/genetics , Mice, Inbred C57BL , Phenotype , Thermogenesis/genetics , Thinness/metabolism , Thinness/geneticsABSTRACT
Chronic stress exposure induces maladaptive behavioral responses and increases susceptibility to neuropsychiatric conditions. However, specific neuronal populations and circuits that are highly sensitive to stress and trigger maladaptive behavioral responses remain to be identified. Here we investigate the patterns of spontaneous activity of proopiomelanocortin (POMC) neurons in the arcuate nucleus (ARC) of the hypothalamus following exposure to chronic unpredictable stress (CUS) for 10 days, a stress paradigm used to induce behavioral deficits such as anhedonia and behavioral despair [1, 2]. CUS exposure increased spontaneous firing of POMC neurons in both male and female mice, attributable to reduced GABA-mediated synaptic inhibition and increased intrinsic neuronal excitability. While acute activation of POMC neurons failed to induce behavioral changes in non-stressed mice of both sexes, subacute (3 days) and chronic (10 days) repeated activation of POMC neurons was sufficient to induce anhedonia and behavioral despair in males but not females under non-stress conditions. Acute activation of POMC neurons promoted susceptibility to subthreshold unpredictable stress in both male and female mice. Conversely, acute inhibition of POMC neurons was sufficient to reverse CUS-induced anhedonia and behavioral despair in both sexes. Collectively, these results indicate that chronic stress induces both synaptic and intrinsic plasticity of POMC neurons, leading to neuronal hyperactivity. Our findings suggest that POMC neuron dysfunction drives chronic stress-related behavioral deficits.
Subject(s)
Anhedonia , Arcuate Nucleus of Hypothalamus , Depression , Neurons , Pro-Opiomelanocortin , Stress, Psychological , Animals , Female , Male , Mice , Acute Disease , Anhedonia/physiology , Arcuate Nucleus of Hypothalamus/metabolism , Arcuate Nucleus of Hypothalamus/physiopathology , Cerebral Cortex/metabolism , Cerebral Cortex/physiopathology , Chronic Disease , Cortical Excitability/physiology , Depression/metabolism , Depression/physiopathology , Disease Models, Animal , Mental Disorders/metabolism , Mental Disorders/physiopathology , Mice, Inbred C57BL , Nervous System Physiological Phenomena , Neuronal Plasticity/physiology , Neurons/metabolism , Neurons/physiology , Pro-Opiomelanocortin/biosynthesis , Pro-Opiomelanocortin/metabolism , Stress, Psychological/metabolism , Stress, Psychological/physiopathology , Synapses/metabolism , Synapses/physiologyABSTRACT
Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and morbidity and mortality rates continue to rise. Atherosclerosis constitutes the principal etiology of CVDs. Endothelial injury, inflammation, and dysfunction are the initiating factors of atherosclerosis. Recently, we reported that endothelial adenosine receptor 2â¯A (ADORA2A), a G protein-coupled receptor (GPCR), plays critical roles in neovascularization disease and cerebrovascular disease. However, the precise role of endothelial ADORA2A in atherosclerosis is still not fully understood. Here, we showed that ADORA2A expression was markedly increased in the aortic endothelium of humans with atherosclerosis or Apoe-/- mice fed a high-cholesterol diet. In vivo studies unraveled that endothelial-specific Adora2a deficiency alleviated endothelial-to-mesenchymal transition (EndMT) and prevented the formation and instability of atherosclerotic plaque in Apoe-/- mice. Moreover, pharmacologic inhibition of ADORA2A with KW6002 recapitulated the anti-atherogenic phenotypes observed in genetically Adora2a-deficient mice. In cultured human aortic endothelial cells (HAECs), siRNA knockdown of ADORA2A or KW6002 inhibition of ADORA2A decreased EndMT, whereas adenoviral overexpression of ADORA2A induced EndMT. Mechanistically, ADORA2A upregulated ALK5 expression via a cAMP/PKA/CREB axis, leading to TGFß-Smad2/3 signaling activation, thereby promoting EndMT. In conclusion, these findings, for the first time, demonstrate that blockade of ADORA2A attenuated atherosclerosis via inhibition of EndMT induced by the CREB1-ALK5 axis. This study discloses a new link between endothelial ADORA2A and EndMT and indicates that inhibiting endothelial ADORA2A could be an effective novel strategy for the prevention and treatment of atherosclerotic CVDs.
Subject(s)
Atherosclerosis , Cyclic AMP Response Element-Binding Protein , Epithelial-Mesenchymal Transition , Mice, Inbred C57BL , Receptor, Adenosine A2A , Receptor, Transforming Growth Factor-beta Type I , Animals , Humans , Male , Mice , Adenosine A2 Receptor Antagonists/pharmacology , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/genetics , Cells, Cultured , Cyclic AMP Response Element-Binding Protein/metabolism , Endothelial Cells/metabolism , Endothelial Cells/drug effects , Endothelial Cells/pathology , Epithelial-Mesenchymal Transition/drug effects , Mice, Knockout , Receptor, Adenosine A2A/metabolism , Receptor, Adenosine A2A/genetics , Receptor, Transforming Growth Factor-beta Type I/genetics , Receptor, Transforming Growth Factor-beta Type I/metabolism , Signal TransductionABSTRACT
BACKGROUND: Proliferation of vascular smooth muscle cells (VSMCs) is a hallmark of arterial diseases, especially in arterial restenosis after angioplasty or stent placement. VSMCs reprogram their metabolism to meet the increased requirements of lipids, proteins, and nucleotides for their proliferation. De novo purine synthesis is one of critical pathways for nucleotide synthesis. However, its role in proliferation of VSMCs in these arterial diseases has not been defined. METHODS: De novo purine synthesis in proliferative VSMCs was evaluated by liquid chromatography-tandem mass spectrometry. The expression of ATIC (5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase), the critical bifunctional enzyme in the last 2 steps of the de novo purine synthesis pathway, was assessed in VSMCs of proliferative arterial neointima. Global and VSMC-specific knockout of Atic mice were generated and used for examining the role of ATIC-associated purine metabolism in the formation of arterial neointima and atherosclerotic lesions. RESULTS: In this study, we found that de novo purine synthesis was increased in proliferative VSMCs. Upregulated purine synthesis genes, including ATIC, were observed in the neointima of the injured vessels and atherosclerotic lesions both in mice and humans. Global or specific knockout of Atic in VSMCs inhibited cell proliferation, attenuating the arterial neointima in models of mouse atherosclerosis and arterial restenosis. CONCLUSIONS: These results reveal that de novo purine synthesis plays an important role in VSMC proliferation in arterial disease. These findings suggest that targeting ATIC is a promising therapeutic approach to combat arterial diseases.
Subject(s)
Atherosclerosis , Hydroxymethyl and Formyl Transferases , Humans , Mice , Animals , Neointima , Purines , Cell Proliferation , Myocytes, Smooth Muscle , Atherosclerosis/geneticsABSTRACT
Social anhedonia, a loss of interest and pleasure in social interactions, is a common symptom of major depression as well as other psychiatric disorders. Depression can occur at any age, but typically emerges in adolescence or early adulthood, which represents a sensitive period for social interaction that is vulnerable to stress. In this study, we evaluated social interaction reward using a conditioned place preference (CPP) paradigm in adolescent male and female mice. Adolescent mice of both sexes exhibited a preference for the social interaction-associated context. Chronic unpredictable stress (CUS) impaired the development of CPP for social interaction, mimicking social anhedonia in depressed adolescents. Conversely, administration of leptin, an adipocyte-derived hormone, enhanced social interaction-induced CPP in non-stressed control mice and reversed social anhedonia in CUS mice. By dissecting the motivational processes of social CPP into social approach and isolation avoidance components, we demonstrated that leptin treatment increased isolation aversion without overt social reward effect. Further mechanistic exploration revealed that leptin stimulated oxytocin gene transcription in the paraventricular nucleus of the hypothalamus, while oxytocin receptor blockade abolished the leptin-induced enhancement of socially-induced CPP. These results establish that chronic unpredictable stress can be used to study social anhedonia in adolescent mice and provide evidence that leptin modulates social motivation possibly via increasing oxytocin synthesis and oxytocin receptor activation.
Subject(s)
Anhedonia , Leptin , Motivation , Animals , Female , Male , Mice , Anhedonia/drug effects , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/metabolism , Leptin/pharmacology , Leptin/therapeutic use , Motivation/drug effects , Oxytocin , Receptors, Oxytocin , Reward , Stress, Psychological/complicationsABSTRACT
[Figure: see text].
Subject(s)
Adenosine Deaminase/genetics , Aortic Aneurysm, Abdominal/metabolism , Muscle, Smooth, Vascular/metabolism , Adenosine Deaminase/metabolism , Animals , Aortic Aneurysm, Abdominal/genetics , Apolipoproteins E/genetics , Cells, Cultured , Humans , Male , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Inbred C57BLABSTRACT
Skeletal muscle atrophy is a progressive chronic disease associated with various conditions, such as aging, cancer, and muscular dystrophy. Interleukin-6 (IL-6) is highly correlated with or plays a crucial role in inducing skeletal muscle atrophy. Extracellular vehicles (EVs), including exosomes, mediate cell-cell communication, and alterations in the genetic material contained in EVs during muscle atrophy may impair muscle cell signaling. Transplantation of muscle progenitor cell-derived EVs (MPC-EVs) is a promising approach for treating muscle diseases such as Duchenne muscular dystrophy (DMD). Moreover, stem cell-derived EVs with modification of microRNAs (e.g., miR-26 and miR-29) have been reported to attenuate muscle atrophy. Unbiased RNA-Seq analysis suggests that MPC-EVs may exert an inhibitory effect on IL-6 pathway. Here, we review the latest advances concerning the mechanisms of stem cell/progenitor cell-derived EVs in alleviating muscle atrophy, including anti-inflammatory and anti-fibrotic effects. We also discuss the clinical application of EVs in the treatment of muscle atrophy.
Subject(s)
Exosomes , Extracellular Vesicles , MicroRNAs , Humans , Interleukin-6 , Muscular Atrophy/therapyABSTRACT
PURPOSE OF REVIEW: To provide a detailed overview of cardiovascular adverse events associated with the use of tyrosine kinase inhibitors across different tumor types. RECENT FINDINGS: Despite an undeniable survival advantage of tyrosine kinase inhibitors (TKIs) in patients with hematologic or solid malignancies, the accompanying off-target cardiovascular adverse events can be life-threatening. In patients with B cell malignancies, the use of Bruton tyrosine kinase inhibitors has been associated with atrial and ventricular arrhythmias, as well as hypertension. Cardiovascular toxic profiles are heterogeneous among the several approved breakpoint cluster region (BCR)-ABL TKIS. Notably, imatinib might be cardioprotective. Vascular endothelial growth factor TKIs, constituting the central axis in the treatment of several solid tumors, including renal cell carcinoma and hepatocellular carcinoma, have strongly been associated with hypertension and arterial ischemic events. Epidermal growth factor TKIs as therapy for advanced non-small cell lung cancer (NSCLC) have been reported to be infrequently associated with heart failure and QT prolongation. While tyrosine kinase inhibitors have been demonstrated to increase overall survival across different types of cancers, special consideration should be given to cardiovascular toxicities. High-risk patients can be identified by undergoing a comprehensive workup at baseline.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Hypertension , Lung Neoplasms , Humans , Protein Kinase Inhibitors/adverse effects , Carcinoma, Non-Small-Cell Lung/chemically induced , Vascular Endothelial Growth Factor A , Lung Neoplasms/chemically inducedABSTRACT
AIMS: The national incidence, risk factors, and associated mortality of atrial fibrillation (AF) in breast cancer patients are unknown. METHODS AND RESULTS: Using the Surveillance, Epidemiology, and End Results-Medicare-linked database, we identified females, ≥66 years old, with a new primary diagnosis of breast cancer from 2007 through 2014. These patients were individually matched 1:1 to Medicare enrolees without cancer, and each pair was followed for 1 year to identify a primary outcome of AF. Cumulative incidence was calculated using competing risk survival statistics. Following this, identifying risk factors of AF among breast cancer patients was conducted using the adjusted Cox proportional hazards model. Finally, Kaplan-Meier methods and adjusted Cox proportional hazards modelling were performed to estimate mortality in breast cancer patients with incident and prevalent AF. This study included 85 423 breast cancer patients. Among these 9425 (11.0%) had AF diagnosis prior to the breast cancer diagnosis. New-onset AF was diagnosed in 2993 (3.9%) patients in a 1-year period after the breast cancer diagnosis [incidence 3.3%, 95% confidence interval (CI) 3.0-3.5%, at 1 year; higher rate in the first 60 days (0.6%/month)]. Comparatively, the incidence of new-onset AF in matched non-cancer controls was 1.8% (95% CI 1.6-2.0%). Apart from traditional demographic and cardiovascular risk factors, breast cancer stage was strongly associated with the development of AF [American Joint Committee on Cancer (AJCC) Stage II/III/IV vs. I: adjusted hazard ratio (aHR) 1.51/2.63/4.21, respectively]. New-onset AF after breast cancer diagnosis (aHR 3.00) is associated with increased 1-year cardiovascular mortality. CONCLUSION: AF incidence is significantly higher in women after a breast cancer diagnosis. Higher breast cancer stages at diagnos are significantly associated with a higher risk of AF. New-onset AF in the new breast cancer diagnosis setting increases 1-year cardiovascular mortality but not breast cancer-related mortality. KEY QUESTION: What are the incidence, prevalence, risk factors and mortality outcomes of atrial fibrillation (AF) in a multi-ethnic representative United States cohort of breast cancer patients? KEY FINDING: Annual incidence for AF is 3.9% with highest rate in the first 60 days after cancer diagnosis. Cancer stage and grade are the strongest risk factors for AF. New onset AF after breast cancer increases all-cause and cardiovascular mortality. TAKE HOME MESSAGE: AF incidence is higher in breast cancer patients and is associated with later stage and grade at diagnosis of breast cancer. Involving cardio-oncology in those who develop AF after cancer diagnosis should be encouraged to improve their cardiovascular and overall prognosis.
Subject(s)
Atrial Fibrillation , Breast Neoplasms , Aged , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Breast Neoplasms/complications , Breast Neoplasms/epidemiology , Female , Humans , Incidence , Medicare , Proportional Hazards Models , Risk Factors , United States/epidemiologyABSTRACT
Prostaglandin D2 (PGD2) released from immune cells or other cell types activates its receptors, D prostanoid receptor (DP)1 and 2 (DP1 and DP2), to promote inflammatory responses in allergic and lung diseases. Prostaglandin-mediated inflammation may also contribute to vascular diseases such as abdominal aortic aneurysm (AAA). However, the role of DP receptors in the pathogenesis of AAA has not been systematically investigated. In the present study, DP1-deficient mice and pharmacological inhibitors of either DP1 or DP2 were tested in two distinct mouse models of AAA formation: angiotensin II (AngII) infusion and calcium chloride (CaCl2) application. DP1-deficient mice [both heterozygous (DP1+/-) and homozygous (DP1-/-)] were protected against CaCl2-induced AAA formation, in conjunction with decreased matrix metallopeptidase (MMP) activity and adventitial inflammatory cell infiltration. In the AngII infusion model, DP1+/- mice, but not DP1-/- mice, exhibited reduced AAA formation. Interestingly, compensatory up-regulation of the DP2 receptor was detected in DP1-/- mice in response to AngII infusion, suggesting a potential role for DP2 receptors in AAA. Treatment with selective antagonists of DP1 (laropiprant) or DP2 (fevipiprant) protected against AAA formation, in conjunction with reduced elastin degradation and aortic inflammatory responses. In conclusion, PGD2 signaling contributes to AAA formation in mice, suggesting that antagonists of DP receptors, which have been extensively tested in allergic and lung diseases, may be promising candidates to ameliorate AAA.
Subject(s)
Aortic Aneurysm, Abdominal/etiology , Receptors, Immunologic/physiology , Receptors, Prostaglandin/physiology , Angiotensin II/pharmacology , Animals , Aortic Aneurysm, Abdominal/prevention & control , Male , Mice , Receptors, Immunologic/antagonists & inhibitors , Receptors, Prostaglandin/antagonists & inhibitorsABSTRACT
Previous studies have shown that AgRP neurons in the arcuate nucleus (ARC) respond to energy deficits and play a key role in the control of feeding behavior and metabolism. Here, we demonstrate that chronic unpredictable stress, an animal model of depression, decreases spontaneous firing rates, increases firing irregularity and alters the firing properties of AgRP neurons in both male and female mice. These changes are associated with enhanced inhibitory synaptic transmission and reduced intrinsic neuronal excitability. Chemogenetic inhibition of AgRP neurons increases susceptibility to subthreshold unpredictable stress. Conversely, chemogenetic activation of AgRP neurons completely reverses anhedonic and despair behaviors induced by chronic unpredictable stress. These results indicate that chronic stress induces maladaptive synaptic and intrinsic plasticity, leading to hypoactivity of AgRP neurons and subsequently causing behavioral changes. Our findings suggest that AgRP neurons in the ARC are a key component of neural circuitry involved in mediating depression-related behaviors and that increasing AgRP neuronal activity coule be a novel and effective treatment for depression.
Subject(s)
Arcuate Nucleus of Hypothalamus , Depression , Agouti-Related Protein/genetics , Agouti-Related Protein/metabolism , Animals , Arcuate Nucleus of Hypothalamus/metabolism , Feeding Behavior , Female , Male , Mice , Neurons/metabolismABSTRACT
BACKGROUND: With the increasing prevalence of gynecologic cancer and obesity, there is a growing population living with cardiovascular disease, obesity and gynecologic cancer concurrently or at risk of developing these disease states. METHODS: We examined cardiovascular (CV) conditions and obesity among 1824 gynecologic cancer survivors in a cross-sectional analysis, using data from the 2020 Behavioral Risk Factor Surveillance System (BRFSS). Univariate and multivariable logistic regression methods were used in the analysis. RESULTS: The prevalence of heart attack, CHD, and stroke were significantly higher (p < 0.001) among survivors of gynecologic and other cancer survivors compared to women with no history of cancer. However, no statistically significant differences were observed across gynecologic and other cancer survivors. The prevalence of obesity among gynecologic cancer survivors was significantly higher (p < 0.001) than that in the other two groups. While around one-third of the women with no history of cancer and survivors of other types of cancer were obese, obesity prevalence was nearly 13%-points higher among survivors of gynecologic cancer. In multivariate analysis, gynecologic cancer survivors were 2.7 times more likely to have a heart attack compared to those without any history of cancer. The odds of CHD and stroke among survivors of gynecologic cancer were respectively 3.4 and 2.7 times that of those with no history of cancer. The adjusted odds were also similar, though smaller in magnitude. Gynecologic cancer survivors were also more likely to be obese -1.8 times that of those with no cancer. CONCLUSIONS: Gynecologic cancer survivors are more likely than persons without a cancer history to have cardiovascular disease and other chronic illnesses, and they have a higher prevalence of heart attack, stroke, and obesity. These results underscore the sizeable opportunities for primary, secondary, and tertiary prevention of cardiovascular health conditions among gynecologic cancer survivors.
Subject(s)
Cancer Survivors , Cardiovascular Diseases , Genital Neoplasms, Female , Myocardial Infarction , Stroke , Behavioral Risk Factor Surveillance System , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Cross-Sectional Studies , Female , Genital Neoplasms, Female/complications , Genital Neoplasms, Female/epidemiology , Humans , Myocardial Infarction/complications , Obesity/complications , Obesity/epidemiology , Prevalence , Stroke/complications , Stroke/etiology , SurvivorsABSTRACT
Perivascular adipose tissue (PVAT) resides at the outermost boundary of the vascular wall, surrounding most conduit blood vessels, except for the cerebral vessels, in humans. A growing body of evidence suggests that inflammation localized within PVAT may contribute to the pathogenesis of cardiovascular disease (CVD). Patients with autoimmune rheumatic diseases (ARDs), e.g., systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), psoriasis, etc., exhibit heightened systemic inflammation and are at increased risk for CVD. Data from clinical studies in patients with ARDs support a linkage between dysfunctional adipose tissue, and PVAT in particular, in disease pathogenesis. Here, we review the data linking PVAT to the pathogenesis of CVD in patients with ARDs, focusing on the role of novel PVAT imaging techniques in defining disease risk and responses to biological therapies.
Subject(s)
Autoimmune Diseases , Cardiovascular Diseases , Respiratory Distress Syndrome , Rheumatic Diseases , Adipose Tissue/physiology , Autoimmune Diseases/complications , Cardiovascular Diseases/pathology , Humans , InflammationABSTRACT
ABSTRACT: Cardiometabolic disease (CMD) is the most common preventable cause of death in the world. A number of components are included in the spectrum of CMD, such as metabolic syndrome/obesity, hyperglycemia/diabetes, dyslipidemia, and hypertension, which are independently associated with cardiovascular disease risk. These conditions often occur together, and patients with cancer frequently undergo treatments that can generate or worsen CMD. This review highlights and presents mechanistic and epidemiological evidence regarding CMD in 4 categories of anticancer medications, namely, mTOR/PI3K-Akt inhibitors, multitargeted tyrosine kinase inhibitor, immune checkpoint inhibitor therapy, and endocrine therapy. Patients taking these medications need careful monitoring during therapy. There is a role for cardio-oncology and onco-primary care specialists in optimally managing patients at risk to mitigate CMD during treatment with these and other investigational anticancer medications.
Subject(s)
Hypertension , Phosphatidylinositol 3-Kinases , Humans , Immune Checkpoint Inhibitors , Protein Kinase Inhibitors/adverse effects , Proto-Oncogene Proteins c-akt , TOR Serine-Threonine KinasesABSTRACT
Increased glycolysis in the lung vasculature has been connected to the development of pulmonary hypertension (PH). We therefore investigated whether glycolytic regulator 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase (PFKFB3)-mediated endothelial glycolysis plays a critical role in the development of PH. Heterozygous global deficiency of Pfkfb3 protected mice from developing hypoxia-induced PH, and administration of the PFKFB3 inhibitor 3PO almost completely prevented PH in rats treated with Sugen 5416/hypoxia, indicating a causative role of PFKFB3 in the development of PH. Immunostaining of lung sections and Western blot with isolated lung endothelial cells showed a dramatic increase in PFKFB3 expression and activity in pulmonary endothelial cells of rodents and humans with PH. We generated mice that were constitutively or inducibly deficient in endothelial Pfkfb3 and found that these mice were incapable of developing PH or showed slowed PH progression. Compared with control mice, endothelial Pfkfb3-knockout mice exhibited less severity of vascular smooth muscle cell proliferation, endothelial inflammation, and leukocyte recruitment in the lungs. In the absence of PFKFB3, lung endothelial cells from rodents and humans with PH produced lower levels of growth factors (such as PDGFB and FGF2) and proinflammatory factors (such as CXCL12 and IL1ß). This is mechanistically linked to decreased levels of HIF2A in lung ECs following PFKFB3 knockdown. Taken together, these results suggest that targeting PFKFB3 is a promising strategy for the treatment of PH.
Subject(s)
Glycolysis , Hypertension, Pulmonary/etiology , Lung/metabolism , Phosphofructokinase-2/physiology , Animals , Disease Models, Animal , Endothelium/metabolism , Gene Knockdown Techniques , Glycolysis/physiology , Humans , Hypertension, Pulmonary/metabolism , Hypoxia/complications , Lung/physiopathology , Male , Mice , Mice, Inbred C57BL , Phosphofructokinase-2/deficiency , Phosphofructokinase-2/metabolism , Rats , Rats, Sprague-DawleyABSTRACT
Atherosclerosis is orchestrated by complex interactions between vascular and inflammatory cells. Traditionally, it has been considered to be an intimal inflammatory disease, characterized by endothelial dysfunction, inflammatory cell recruitment, lipid oxidation, and foam cell formation. This inside-out signaling paradigm has been accepted as dogma for many years, despite the fact that inflammatory cells are far more prevalent in the adventitia compared with the intima. For decades, the origin of adventitial inflammation in atherosclerosis was unknown. The fact that these inflammatory cells were observed to cluster at the margin of perivascular adipose tissues-a unique and highly inflammatory adipose depot that surrounds most atherosclerosis-prone blood vessels-has stimulated interest in perivascular adipose tissue-mediated outside-in signaling in vascular pathophysiology, including atherosclerosis. The phenotype of perivascular adipocytes underlies the functional characteristics of this depot, including its role in adventitial inflammatory cell recruitment, trafficking to the intima via the vasa vasorum, and atherosclerosis perturbation. This review is focused on emerging concepts pertaining to outside-in signaling in atherosclerosis driven by dysfunctional perivascular adipose tissues during diet-induced obesity and recent strategies for atherosclerosis prediction and prognostication based upon this hypothesis.