Cardiovascular Diseases Commons^™

Adenosine Metabolized From Extracellular Atp Ameliorates Organ Injury By Triggering A2br Signaling, Taha Kelestemur, Zoltán H Németh, Pal Pacher, Jennet Beesley, Simon C Robson, Holger K Eltzschig, György Haskó

Faculty, Staff and Student Publications

BACKGROUND: Trauma and a subsequent hemorrhagic shock (T/HS) result in insufficient oxygen delivery to tissues and multiple organ failure. Extracellular adenosine, which is a product of the extracellular degradation of adenosine 5' triphosphate (ATP) by the membrane-embedded enzymes CD39 and CD73, is organ protective, as it participates in signaling pathways, which promote cell survival and suppress inflammation through adenosine receptors including the A

METHODS: T/HS shock was induced by blood withdrawal from the femoral artery in wild-type, global knockout (CD39, CD73, A

RESULTS: T/HS upregulated the expression of CD39, CD73, and the A

CONCLUSION: In conclusion, the CD39-CD73-A

An Improved Reporter Identifies Ruxolitinib As A Potent And Cardioprotective Camkii Inhibitor, Oscar E Reyes Gaido, Nikoleta Pavlaki, Jonathan M Granger, Olurotimi O Mesubi, Bian Liu, Brian L Lin, Alan Long, David Walker, Joshua Mayourian, Kate L Schole, Chantelle E Terrillion, Lubika J Nkashama, Mohit M Hulsurkar, Lauren E Dorn, Kimberly M Ferrero, Richard L Huganir, Frank U Müller, Xander H T Wehrens, Jun O Liu, Elizabeth D Luczak, Vassilios J Bezzerides, Mark E Anderson

Faculty, Staff and Students Publications

Ca2+/calmodulin-dependent protein kinase II (CaMKII) hyperactivity causes cardiac arrhythmias, a major source of morbidity and mortality worldwide. Despite proven benefits of CaMKII inhibition in numerous preclinical models of heart disease, translation of CaMKII antagonists into humans has been stymied by low potency, toxicity, and an enduring concern for adverse effects on cognition due to an established role of CaMKII in learning and memory. To address these challenges, we asked whether any clinically approved drugs, developed for other purposes, were potent CaMKII inhibitors. For this, we engineered an improved fluorescent reporter, CaMKAR (CaMKII activity reporter), which features superior sensitivity, kinetics, and …

Prolylcarboxypeptidase Alleviates Hypertensive Cardiac Remodeling By Regulating Myocardial Tissue Angiotensin Ii, Binh Y Nguyen, Fangchao Zhou, Pablo Binder, Wei Liu, Susanne S Hille, Xiaojing Luo, Min Zi, Hongyuan Zhang, Antony Adamson, Fozia Z Ahmed, Sam Butterworth, Elizabeth J Cartwright, Oliver J Müller, Kaomei Guan, Elizabeth M Fitzgerald, Xin Wang

Faculty, Staff and Student Publications

Background Prolonged activation of angiotensin II is the main mediator that contributes to the development of heart diseases, so converting angiotensin II into angiotensin 1-7 has emerged as a new strategy to attenuate detrimental effects of angiotensin II. Prolylcarboxypeptidase is a lysosomal pro-X carboxypeptidase that is able to cleave angiotensin II at a preferential acidic pH optimum. However, insufficient attention has been given to the cardioprotective functions of prolylcarboxylpeptidase. Methods and Results We established a CRISPR/CRISPR-associated protein 9-mediated global prolylcarboxylpeptidase-knockout and adeno-associated virus serotype 9-mediated cardiac prolylcarboxylpeptidase overexpression mouse models, which were challenged with the angiotensin II infusion (2 mg/kg …

Targeting Neddylation And Sumoylation In Chemoresistant Triple Negative Breast Cancer, Wei Ruan, Jiwen Li, Seungwon Choi, Xinxin Ma, Yafen Liang, Ragini Nair, Xiaoyi Yuan, Tingting W Mills, Holger K Eltzschig

Faculty, Staff and Student Publications

Previous studies implicate extracellular adenosine signaling in attenuating myocardial ischemia and reperfusion injury (IRI). This extracellular adenosine signaling is terminated by its uptake into cells by equilibrative nucleoside transporters (ENTs). Thus, we hypothesized that targeting ENTs would function to increase cardiac adenosine signaling and concomitant cardioprotection against IRI. Mice were exposed to myocardial ischemia and reperfusion injury. Myocardial injury was attenuated in mice treated with the nonspecific ENT inhibitor dipyridamole. A comparison of mice with global Ent1 or Ent2 deletion showed cardioprotection only in Ent1-/- mice. Moreover, studies with tissue-specific Ent deletion revealed that mice with myocyte-specific Ent1 deletion (Ent1loxP/loxP …

Cardiac Pericytes Mediate The Remodeling Response To Myocardial Infarction, Pearl Quijada, Shuin Park, Peng Zhao, Kamal Ss Kolluri, David Wong, Kevin D Shih, Kai Fang, Arash Pezhouman, Lingjun Wang, Ali Daraei, Matthew D Tran, Elle M Rathbun, Kimberly N Burgos Villar, Maria L Garcia-Hernandez, Thanh Td Pham, Charles J Lowenstein, M Luisa Iruela-Arispe, S Thomas Carmichael, Eric M Small, Reza Ardehali

Faculty, Staff and Students Publications

Despite the prevalence of pericytes in the microvasculature of the heart, their role during ischemia-induced remodeling remains unclear. We used multiple lineage-tracing mouse models and found that pericytes migrated to the injury site and expressed profibrotic genes, coinciding with increased vessel leakage after myocardial infarction (MI). Single-cell RNA-Seq of cardiac pericytes at various time points after MI revealed the temporally regulated induction of genes related to vascular permeability, extracellular matrix production, basement membrane degradation, and TGF-β signaling. Deleting TGF-β receptor 1 in chondroitin sulfate proteoglycan 4-expressing (Cspg4-expressing) cells reduced fibrosis following MI, leading to a transient improvement in the cardiac …

Mecp2 Regulates Gdf11, A Dosage-Sensitive Gene Critical For Neurological Function, Sameer S Bajikar, Ashley G Anderson, Jian Zhou, Mark A Durham, Alexander J Trostle, Ying-Wooi Wan, Zhandong Liu, Huda Y Zoghbi

Faculty, Staff and Students Publications

Loss- and gain-of-function of MeCP2 causes Rett syndrome (RTT) and MECP2 duplication syndrome (MDS), respectively. MeCP2 binds methyl-cytosines to finely tune gene expression in the brain, but identifying genes robustly regulated by MeCP2 has been difficult. By integrating multiple transcriptomics datasets, we revealed that MeCP2 finely regulates growth differentiation factor 11 (Gdf11). Gdf11 is down-regulated in RTT mouse models and, conversely, up-regulated in MDS mouse models. Strikingly, genetically normalizing Gdf11 dosage levels improved several behavioral deficits in a mouse model of MDS. Next, we discovered that losing one copy of Gdf11 alone was sufficient to cause multiple neurobehavioral …

Control Of Sars-Cov-2 Infection By Mt1-Mmp-Mediated Shedding Of Ace2, Xuanming Guo, Jianli Cao, Jian-Piao Cai, Jiayan Wu, Jiangang Huang, Pallavi Asthana, Sheung Kin Ken Wong, Zi-Wei Ye, Susma Gurung, Yijing Zhang, Sheng Wang, Zening Wang, Xin Ge, Hiu Yee Kwan, Aiping Lyu, Kui Ming Chan, Nathalie Wong, Jiandong Huang, Zhongjun Zhou, Zhao-Xiang Bian, Shuofeng Yuan, Hoi Leong Xavier Wong

Faculty, Staff and Student Publications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. Angiotensin-converting enzyme 2 (ACE2) is an entry receptor for SARS-CoV-2. The full-length membrane form of ACE2 (memACE2) undergoes ectodomain shedding to generate a shed soluble form (solACE2) that mediates SARS-CoV-2 entry via receptor-mediated endocytosis. Currently, it is not known how the physiological regulation of ACE2 shedding contributes to the etiology of COVID-19 in vivo. The present study identifies Membrane-type 1 Matrix Metalloproteinase (MT1-MMP) as a critical host protease for solACE2-mediated SARS-CoV-2 infection. SARS-CoV-2 infection leads to increased activation of MT1-MMP that is colocalized with ACE2 in human lung …

Genetic Inhibition Of Nuclear Factor Of Activated T-Cell C2 Prevents Atrial Fibrillation In Crem Transgenic Mice, Li Ni, Satadru K Lahiri, Jiali Nie, Xiaolu Pan, Issam Abu-Taha, Julia O Reynolds, Hannah M Campbell, Haihao Wang, Markus Kamler, Wilhelm Schmitz, Frank Ulrich Müller, Na Li, Xiang Wei, Dao Wen Wang, Dobromir Dobrev, Xander H T Wehrens

Faculty, Staff and Students Publications

AIMS: Abnormal intracellular calcium (Ca2+) handling contributes to the progressive nature of atrial fibrillation (AF), the most common sustained cardiac arrhythmia. Evidence in mouse models suggests that activation of the nuclear factor of activated T-cell (NFAT) signalling pathway contributes to atrial remodelling. Our aim was to determine the role of NFATc2 in AF in humans and mouse models.

METHODS AND RESULTS: Expression levels of NFATc1-c4 isoforms were assessed by quantitative reverse transcription-polymerase chain reaction in right atrial appendages from patients with chronic AF (cAF). NFATc1 and NFATc2 mRNA levels were elevated in cAF patients compared with those in normal sinus …

Anesthesia For Echocardiography And Magnetic Resonance Imaging In The African Clawed Frog (Xenopus Laevis), Antonio F Corno, Noelia E Flores, Wen Li, Thomas H Gomez, Jorge D Salazar

Faculty, Staff and Student Publications

This report describes an anesthesia technique that we used to study cardiovascular anatomy and physiology with echocardiography and cardiac magnetic resonance (CMR) in 46 African clawed frogs (Xenopus laevis) (n = 24 for electrocardiography and n = 22 for CMR). For administration of anesthesia, 3 holding tanks, one each for transportation, sedation, and recovery, were filled with filtered water, with 0.05% buffered tricaine methasulfonate solution (MS-222) added into the sedation tank. Fifteen minutes after the frog was placed in the sedation tank, a paper towel was soaked in MS-222 solution, and the frog was placed in a …

Sirpα Mediates Igf1 Receptor In Cardiomyopathy-Induced By Chronic Kidney Disease, Sandhya S Thomas, Jiao Wu, Giovanni Davogustto, Michael W Holliday, Kristin Eckel-Mahan, Daniela Verzola, Giacomo Garibotto, Zhaoyong Hu, William E Mitch, Heinrich Taegtmeyer

Faculty, Staff and Student Publications

BACKGROUND: Chronic kidney disease (CKD) is characterized by increased myocardial mass despite near-normal blood pressure, suggesting the presence of a separate trigger. A potential driver is SIRPα (signal regulatory protein alpha)-a mediator impairing insulin signaling. The objective of this study is to assess the role of circulating SIRPα in CKD-induced adverse cardiac remodeling.

METHODS: SIRPα expression was evaluated in mouse models and patients with CKD. Specifically, mutant, muscle-specific, or cardiac muscle-specific SIRPα KO (knockout) mice were examined after subtotal nephrectomy. Cardiac function was assessed by echocardiography. Metabolic responses were confirmed in cultured muscle cells or cardiomyocytes.

RESULTS: We demonstrate that …

Prolonged Cardiac Nr4a2 Aactivation Causes Dilated Cardiomyopathy In Mice, Sadia Ashraf, Heinrich Taegtmeyer, Romain Harmancey

Faculty, Staff and Student Publications

Transcription factors play a fundamental role in cardiovascular adaptation to stress. Nuclear receptor subfamily 4 group A member 2 (NR4A2; NURR1) is an immediate-early gene and transcription factor with a versatile role throughout many organs. In the adult mammalian heart, and particularly in cardiac myocytes, NR4A2 is strongly up-regulated in response to beta-adrenergic stimulation. The physiologic implications of this increase remain unknown. In this study, we aimed to interrogate the consequences of cardiac NR4A2 up-regulation under normal conditions and in response to pressure overload. In mice, tamoxifen-dependent, cardiomyocyte-restricted overexpression of NR4A2 led to cardiomyocyte hypertrophy, left ventricular dilation, heart failure, …

Evaluation Of Long-Chain Fatty Acid Respiration In Neonatal Mouse Cardiomyocytes Using Seahorse Instrument, Aude Angelini, Xinchun Pi, Liang Xie

Faculty, Staff and Students Publications

Metabolic switches play a critical role in the pathophysiology of cardiac diseases, including heart failure. Here, we describe an assay for long-chain fatty acid oxidation in neonatal mouse cardiomyocytes by using a SeaHorse Flux Analyzer (Agilent). This protocol is a simplified but robust adaptation of the standard protocol that enables metabolic measurements in cells isolated from transgenic mouse models, which can be timesaving and informative. Cell isolation and culture represent a critical point that may require bench optimization.

For complete details on the use and execution of this protocol, please refer to Angelini et al. (2021).

Lmod2-Related Dilated Cardiomyopathy Presenting In Late Infancy, Erica Lay, Mahshid S Azamian, Susan W Denfield, William Dreyer, Joseph A Spinner, Debra Kearney, Lilei Zhang, Kim C Worley, Weimin Bi, Seema R Lalani

Faculty, Staff and Students Publications

Leiomodin-2 (LMOD2) is an important regulator of the thin filament length, known to promote elongation of actin through polymerization at pointed ends. Mice with Lmod2 deficiency die around 3 weeks of age due to severe dilated cardiomyopathy (DCM), resulting from decreased heart contractility due to shorter thin filaments. To date, there have been three infants from two families reported with biallelic variants in LMOD2, presenting with perinatal onset DCM. Here, we describe a third family with a child harboring a previously described homozygous frameshift variant, c.1243_1244delCT (p.L415Vfs*108) with DCM, presenting later in infancy at 9 months of age. Family history …

Poloxamer 407 Induces Hypertriglyceridemia But Decreases Atherosclerosis In Ldlr -/- Mice, Xueying Peng, Zeqin Lian, Xiao-Yuan Dai Perrard, Yunjie Xiao, Jing Ni, Veronica O'Brien, Henry Dong, Henry J Pownall, Christie M Ballantyne, Huaizhu Wu

Faculty, Staff and Students Publications

Background: Hypertriglyceridemia (HTG) increases the risk for atherosclerotic cardiovascular disease, but underlying mechanisms are incompletely understood. Circulating monocytes play an important role in atherogenesis by infiltrating arterial walls, where they differentiate into macrophages. We tested the hypothesis that HTG is mechanistically linked to atherogenesis by altering the monocyte phenotype and infiltration into atherosclerotic lesions in a model of diet-induced atherogenesis in Ldlr−/− mice. Methods: HTG was induced in male Ldlr−/− mice, fed a Western, high-fat high-cholesterol diet, by daily injection of poloxamer 407 (P407), a lipoprotein lipase inhibitor, for seven weeks. Atherosclerosis, monocyte phenotypes, and monocyte migration into atherosclerotic lesions …

Alterations Of The Gut Microbial Community Structure And Function With Aging In The Spontaneously Hypertensive Stroke Prone Rat, Huanan Shi, James W Nelson, Sharon Phillips, Joseph F Petrosino, Robert M Bryan, David J Durgan

Faculty, Staff and Students Publications

Gut dysbiosis, a pathological imbalance of bacteria, has been shown to contribute to the development of hypertension (HT), systemic- and neuro-inflammation, and blood-brain barrier (BBB) disruption in spontaneously hypertensive stroke prone rats (SHRSP). However, to date individual species that contribute to HT in the SHRSP model have not been identified. One potential reason, is that nearly all studies of the SHRSP gut microbiota have analyzed samples from rats with established HT. The goal of this study was to examine the SHRSP gut microbiota before, during, and after the onset of hypertension, and in normotensive WKY control rats over the same …

Mitochondrial Sirtuin-3 (Sirt3) Prevents Doxorubicin-Induced Dilated Cardiomyopathy By Modulating Protein Acetylation And Oxidative Stress, Mateusz M Tomczyk, Kyle G Cheung, Bo Xiang, Nahid Tamanna, Ana L Fonseca Teixeira, Prasoon Agarwal, Stephanie M Kereliuk, Victor Spicer, Ligen Lin, Jason Treberg, Qiang Tong, Vernon W Dolinsky

Faculty, Staff and Students Publications

BACKGROUND: High doses of doxorubicin put cancer patients at risk for developing dilated cardiomyopathy. Previously, we showed that doxorubicin treatment decreases SIRT3 (sirtuin 3), the main mitochondrial deacetylase and increases protein acetylation in rat cardiomyocytes. Here, we hypothesize that SIRT3 expression can attenuate doxorubicin induced dilated cardiomyopathy in vivo by preventing the acetylation of mitochondrial proteins.

METHODS: Nontransgenic, M3-SIRT3 (truncated SIRT3; short isoform), and M1-SIRT3 (full-length SIRT3; mitochondrial localized) transgenic mice were treated with doxorubicin for 4 weeks (8 mg/kg body weight per week). Echocardiography was performed to assess cardiac structure and function and validated by immunohistochemistry and immunofluorescence (n=4-10). …

Free Cholesterol Bioavailability And Atherosclerosis, Rei J Abe, Jun-Ichi Abe, Minh T H Nguyen, Elizabeth A Olmsted-Davis, Abrar Mamun, Priyanka Banerjee, John P Cooke, Longhou Fang, Henry Pownall, Nhat-Tu Le

Faculty, Staff and Student Publications

Purpose of review: As both a cholesterol acceptor and carrier in the reverse cholesterol transport (RCT) pathway, high-density lipoprotein (HDL) is putatively atheroprotective. However, current pharmacological therapies to increase plasma HDL cholesterol (HDL-c) concentration have paradoxically failed to prevent or reduce atherosclerosis and cardiovascular disease (CVD). Given that free cholesterol (FC) transfer between surfaces of lipoproteins and cells is reversible, excess plasma FC can be transferred to the cells of peripheral tissue sites resulting in atherosclerosis. Here, we summarize potential mechanisms contributing to this paradox and highlight the role of excess free cholesterol (FC) bioavailability in atherosclerosis vs. atheroprotection.

Recent …

Myocardial Rev-Erb-Mediated Diurnal Metabolic Rhythm And Obesity Paradox, Shiyang Song, Chih-Liang Tien, Hao Cui, Paul Basil, Ningxia Zhu, Yingyun Gong, Wenbo Li, Hui Li, Qiying Fan, Jong Min Choi, Weijia Luo, Yanfeng Xue, Rui Cao, Wenjun Zhou, Andrea R Ortiz, Brittany Stork, Vatsala Mundra, Nagireddy Putluri, Brian York, Maoping Chu, Jiang Chang, Sung Yun Jung, Liang Xie, Jiangping Song, Lilei Zhang, Zheng Sun

Faculty, Staff and Students Publications

BACKGROUND: The nuclear receptor Rev-erbα/β, a key component of the circadian clock, emerges as a drug target for heart diseases, but the function of cardiac Rev-erb has not been studied in vivo. Circadian disruption is implicated in heart diseases, but it is unknown whether cardiac molecular clock dysfunction is associated with the progression of any naturally occurring human heart diseases. Obesity paradox refers to the seemingly protective role of obesity for heart failure, but the mechanism is unclear.

METHODS: We generated mouse lines with cardiac-specific Rev-erbα/β knockout (KO), characterized cardiac phenotype, conducted multi-omics (RNA-sequencing, chromatin immunoprecipitation sequencing, proteomics, and metabolomics) …

Common Genetic Variants Contribute To Risk Of Transposition Of The Great Arteries, Doris Škorić-Milosavljević, Rafik Tadros, Fernanda M Bosada, Federico Tessadori, Jan Hendrik Van Weerd, Odilia I Woudstra, Fleur V Y Tjong, Najim Lahrouchi, Fanny Bajolle, Heather J Cordell, A J Agopian, Gillian M Blue, Daniela Q C M Barge-Schaapveld, Marc Gewillig, Christoph Preuss, Elisabeth M Lodder, Phil Barnett, Aho Ilgun, Leander Beekman, Karel Van Duijvenboden, Regina Bokenkamp, Martina Müller-Nurasyid, Hubert W Vliegen, Thelma C Konings, Joost P Van Melle, Arie P J Van Dijk, Roland R J Van Kimmenade, Jolien W Roos-Hesselink, Gertjan T Sieswerda, Folkert Meijboom, Hashim Abdul-Khaliq, Felix Berger, Sven Dittrich, Marc-Phillip Hitz, Julia Moosmann, Frank-Thomas Riede, Stephan Schubert, Pilar Galan, Mark Lathrop, Hans M Munter, Ammar Al-Chalabi, Christopher E Shaw, Pamela J Shaw, Karen E Morrison, Jan H Veldink, Leonard H Van Den Berg, Sylvia Evans, Marcelo A Nobrega, Ivy Aneas, Milena Radivojkov-Blagojević, Thomas Meitinger, Erwin Oechslin, Tapas Mondal, Lynn Bergin, John F Smythe, Luis Altamirano-Diaz, Jane Lougheed, Berto J Bouma, Marie-A Chaix, Jennie Kline, Anne S Bassett, Gregor Andelfinger, Roel L F Van Der Palen, Patrice Bouvagnet, Sally-Ann B Clur, Jeroen Breckpot, Wilhelmina S Kerstjens-Frederikse, David S Winlaw, Ulrike M M Bauer, Seema Mital, Elizabeth Goldmuntz, Bernard Keavney, Damien Bonnet, Barbara J Mulder, Michael W T Tanck, Jeroen Bakkers, Vincent M Christoffels, Cornelis J Boogerd, Alex V Postma, Connie R Bezzina

Faculty, Staff and Student Publications

RATIONALE: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored.

OBJECTIVE: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA.

METHODS AND RESULTS: We conducted a genome-wide association study in an international set of 1,237 patients …

Phds/Cpt1b/Vdac1 Axis Regulates Long-Chain Fatty Acid Oxidation In Cardiomyocytes, Aude Angelini, Pradip K Saha, Antrix Jain, Sung Yun Jung, Randall L Mynatt, Xinchun Pi, Liang Xie

Faculty, Staff and Students Publications

Cardiac metabolism is a high-oxygen-consuming process, showing a preference for long-chain fatty acid (LCFA) as the fuel source under physiological conditions. However, a metabolic switch (favoring glucose instead of LCFA) is commonly reported in ischemic or late-stage failing hearts. The mechanism regulating this metabolic switch remains poorly understood. Here, we report that loss of PHD2/3, the cellular oxygen sensors, blocks LCFA mitochondria uptake and β-oxidation in cardiomyocytes. In high-fat-fed mice, PHD2/3 deficiency improves glucose metabolism but exacerbates the cardiac defects. Mechanistically, we find that PHD2/3 bind to CPT1B, a key enzyme of mitochondrial LCFA uptake, promoting CPT1B-P295 hydroxylation. Further, we …

Cellular Regeneration As A Potential Strategy To Treat Cardiac Conduction Disorders, Satadru K Lahiri, Mohit M Hulsurkar, Xander Ht Wehrens

Faculty, Staff and Students Publications

Loss of atrioventricular conduction system (AVCS) cells due to either inherited or acquired deficits leads to conduction diseases, which can deteriorate into fatal cardiac arrhythmias and sudden death. In this issue of the JCI, Wang et al. constructed a mouse model of atrioventricular block (AVB) by inducing AVCS cell-specific injury using the Cx30.2 enhancer to drive expression of diphtheria toxin fragment A. AVCS cell ablation in adult mice led to irreversible AVB. jkjkIn contrast, AVCS cell injury in neonatal mice was followed by spontaneous recovery in a subset of mice, revealing a limited postnatal time window during which the regeneration …

Ucp3 (Uncoupling Protein 3) Insufficiency Exacerbates Left Ventricular Diastolic Dysfunction During Angiotensin Ii-Induced Hypertension, Xu Chen, Sadia Ashraf, Nadia Ashraf, Romain Harmancey

Faculty, Staff and Student Publications

Background Left ventricular diastolic dysfunction, an early stage in the pathogenesis of heart failure with preserved ejection fraction, is exacerbated by joint exposure to hypertension and obesity; however, the molecular mechanisms involved remain uncertain. The mitochondrial UCP3 (uncoupling protein 3) is downregulated in the heart with obesity. Here, we used a rat model of UCP3 haploinsufficiency (ucp3

Endothelium-Specific Depletion Of Lrp1 Improves Glucose Homeostasis Through Inducing Osteocalcin, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Cristian Coarfa, Kimal Rajapakshe, Dimuthu Perera, Jizhong Cheng, Huaizhu Wu, Christie M Ballantyne, Zheng Sun, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

The vascular endothelium is present within metabolic organs and actively regulates energy metabolism. Here we show osteocalcin, recognized as a bone-secreted metabolic hormone, is expressed in mouse primary endothelial cells isolated from heart, lung and liver. In human osteocalcin promoter-driven green fluorescent protein transgenic mice, green fluorescent protein signals are enriched in endothelial cells lining aorta, small vessels and capillaries and abundant in aorta, skeletal muscle and eye of adult mice. The depletion of lipoprotein receptor-related protein 1 induces osteocalcin through a Forkhead box O -dependent pathway in endothelial cells. Whereas depletion of osteocalcin abolishes the glucose-lowering effect of low-density …

Cd11c Participates In Triggering Acute Graft-Versus-Host Disease During Bone Marrow Transplantation, Qianqian Wang, Xiuhua Su, Yi He, Mei Wang, Donglin Yang, Rongli Zhang, Jialin Wei, Qiaoling Ma, Weihua Zhai, Aiming Pang, Yong Huang, Sizhou Feng, Christie M Ballantyne, Huaizhu Wu, Xiaolei Pei, Xiaoming Feng, Mingzhe Han, Erlie Jiang

Faculty, Staff and Students Publications

CD11c is a canonical dendritic cell (DC) marker with poorly defined functions in the immune system. Here, we found that blocking CD11c on human peripheral blood mononuclear cell‐derived DCs (MoDCs) inhibited the proliferation of CD4+ T cells and the differentiation into IFN‐γ‐producing T helper 1 (Th1) cells, which were critical in acute graft‐versus‐host disease (aGVHD) pathogenesis. Using allogeneic bone marrow transplantation (allo‐BMT) murine models, we consistently found that CD11c‐deficient recipient mice had alleviated aGVHD symptoms for the decreased IFN‐γ‐expressing CD4+ Th1 cells and CD8+ T cells. Transcriptional analysis showed that CD11c participated in several immune regulation functions including maintaining antigen …

Nlrp3 Inflammasome Is A Key Driver Of Obesity-Induced Atrial Arrhythmias, Larry Scott, Anke C Fender, Arnela Saljic, Luge Li, Xiaohui Chen, Xiaolei Wang, Dominik Linz, Jilu Lang, Mathias Hohl, Darragh Twomey, Thuy T Pham, Rodrigo Diaz-Lankenau, Mihail G Chelu, Markus Kamler, Mark L Entman, George E Taffet, Prashanthan Sanders, Dobromir Dobrev, Na Li

Faculty, Staff and Students Publications

AIMS: Obesity, an established risk factor of atrial fibrillation (AF), is frequently associated with enhanced inflammatory response. However, whether inflammatory signaling is causally linked to AF pathogenesis in obesity remains elusive. We recently demonstrated that the constitutive activation of the 'NACHT, LRR, and PYD Domains-containing Protein 3' (NLRP3) inflammasome promotes AF susceptibility. In this study, we hypothesized that the NLRP3 inflammasome is a key driver of obesity-induced AF.

METHODS AND RESULTS: Western blotting was performed to determine the level of NLRP3 inflammasome activation in atrial tissues of obese patients, sheep, and diet-induced obese (DIO) mice. The increased body weight in …

Loss Of Bone Morphogenetic Protein-Binding Endothelial Regulator Causes Insulin Resistance, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Huaizhu Wu, Christie M Ballantyne, Sean M Hartig, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

Accumulating evidence suggests that chronic inflammation of metabolic tissues plays a causal role in obesity-induced insulin resistance. Yet, how specific endothelial factors impact metabolic tissues remains undefined. Bone morphogenetic protein (BMP)–binding endothelial regulator (BMPER) adapts endothelial cells to inflammatory stress in diverse organ microenvironments. Here, we demonstrate that BMPER is a driver of insulin sensitivity. Both global and endothelial cell-specific inducible knockout of BMPER cause hyperinsulinemia, glucose intolerance and insulin resistance without increasing inflammation in metabolic tissues in mice. BMPER can directly activate insulin signaling, which requires its internalization and interaction with Niemann-Pick C1 (NPC1), an integral membrane protein that …

Glucagon Blockade Restores Functional Β-Cell Mass In Type 1 Diabetic Mice And Enhances Function Of Human Islets, May-Yun Wang, E Danielle Dean, Ezekiel Quittner-Strom, Yi Zhu, Kamrul H Chowdhury, Zhuzhen Zhang, Shangang Zhao, Na Li, Reshing Ye, Young Lee, Yiyi Zhang, Shiuhwei Chen, Xinxin Yu, Derek C Leonard, Greg Poffenberger, Alison Von Deylen, S Kay Mccorkle, Amnon Schlegel, Kyle W Sloop, Alexander M Efanov, Ruth E Gimeno, Philipp E Scherer, Alvin C Powers, Roger H Unger, William L Holland

Faculty, Staff and Students Publications

We evaluated the potential for a monoclonal antibody antagonist of the glucagon receptor (Ab-4) to maintain glucose homeostasis in type 1 diabetic rodents. We noted durable and sustained improvements in glycemia which persist long after treatment withdrawal. Ab-4 promoted β-cell survival and enhanced the recovery of insulin+ islet mass with concomitant increases in circulating insulin and C peptide. In PANIC-ATTAC mice, an inducible model of β-cell apoptosis which allows for robust assessment of β-cell regeneration following caspase-8–induced diabetes, Ab-4 drove a 6.7-fold increase in β-cell mass. Lineage tracing suggests that this restoration of functional insulin-producing cells was at least partially …

The Crosstalk Between Cardiomyocyte Calcium And Inflammasome Signaling Pathways In Atrial Fibrillation, Xiaolei Wang, Xiaohui Chen, Dobromir Dobrev, Na Li

Faculty, Staff and Students Publications

Atrial fibrillation (AF) is the most frequent arrhythmia in adults. The prevalence and incidence of AF is going to increase substantially over the next a few decades. Because AF increases the risk of stroke, heart failure, dementia, and others, it severely impacts the quality of life, morbidity and mortality. Although the pathogenesis of AF is multifaceted and complex, focal ectopic activity and reentry are considered as the fundamental proarrhythmic mechanisms underlying AF development. Over the past 2 decades, large amount of evidence points to the key role of intracellular Ca2+ dysregulation in both initiation and maintenance of AF. More recently, …

Deficiency Of Stat1 In Cd11c+ Cells Alters Adipose Tissue Inflammation And Improves Metabolic Dysfunctions In Mice Fed A High-Fat Diet, Antu Antony, Zeqin Lian, Xiaoyuan Dai Perrard, Jerry Perrard, Hua Liu, Aaron R Cox, Pradip Saha, Lothar Hennighausen, Sean M Hartig, Christie M Ballantyne, Huaizhu Wu

Faculty, Staff and Students Publications

CD11c+ macrophages/dendritic cells (MDCs) are increased and display the classically activated M1-like phenotype in obese adipose tissue (AT) and may contribute to AT inflammation and insulin resistance. Stat1 is a key transcription factor for MDC polarization into the M1-like phenotype. Here, we examined the role of Stat1 in obesity-induced AT MDC polarization and inflammation and insulin resistance using mice with specific knockout of Stat1 in MDCs (cKO). Stat1 was upregulated and phosphorylated, indicating activation, early and persistently in AT and AT MDCs of wild-type mice fed a high-fat diet (HFD). Compared with littermate controls, cKO mice fed an HFD (16 …

Conformation-Dependent Blockage Of Activated Vwf Improves Outcomes Of Traumatic Brain Injury In Mice, Xin Xu, Chenyu Wang, Yingang Wu, Katie Houck, Tristan Hilton, Ashley Zhou, Xiaoping Wu, Cha Han, Mengchen Yang, Wei Yang, Fu-Dong Shi, Moritz Stolla, Miguel A Cruz, Min Li, Jianning Zhang, Jing-Fei Dong

Faculty, Staff and Students Publications

Traumatic brain injury-induced coagulopathy (TBI-IC) causes life-threatening secondary intracranial bleeding. Its pathogenesis differs mechanistically from that of coagulopathy arising from extracranial injuries and hemorrhagic shock, but it remains poorly understood. We report results of a study designed to test the hypothesis that von Willebrand factor (VWF) released during acute TBI is intrinsically hyperadhesive because its platelet-binding A1-domain is exposed and contributes to TBI-induced vascular leakage and consumptive coagulopathy. This hyperadhesive VWF can be selectively blocked by a VWF A2-domain protein to prevent TBI-IC and to improve neurological function with a minimal risk of bleeding. We demonstrated that A2 given through …