bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 424: Knockdown of Nerve Growth Factor in Spinal Cord Reduces Myocardial Reperfusion Injury by Suppressing Ischemic Nociceptive Signaling Transmission
Authors: He Shufang , Dou Mengyun , Ma Zhenxiao , Zhang Ye
Published: February 2019

Objective:
To test the hypothesis that nerve growth factor (NGF) sensitized spinal cardiac afferent activity contributes to myocardial ischemia-reperfusion injury (IRI).

Methods and Results:
The expression levels of NGF were increased in both dorsal root ganglion (DRG) and spinal cord after myocardial IRI in rats. Whole-cell patch clamp in cultured DRG neurons revealed that NGF aggravated capsaicin-induced current which was eliminated by the transient receptor potential vanilloid 1 (TRPV1) antagonist. Intrathecal injection of lentivirus-mediated NGF shRNA into thoracic T1-T8 segments successfully suppressed NGF mRNA and protein levels. Knockdown of NGF in spinal cord significantly limited IRI-induced infarct size, lowered down the concentration of cardiac troponin I (cTnI), and improved arrhythmia score. NGF gene suppression markedly reduced IRI-caused elevation of NGF and its receptor tropomyosin receptor kinase A (TrkA), TRPV1 and phosphorylated TRPV1. The activation of protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) was also inhibited by NGF shRNA. Upon immunofluorescence staining, substance P (SP) and calcitonin gene-related peptide (CGRP) were found strongly stained in DRG and spinal dorsal horn following myocardial IRI, while these immunoreactive staining were repressed due to NGF gene knockdown.

Conclusions:
NGF aggravated spinal cardiac afferent nerves activity by sensitizing TRPV1-mediated nociceptive signal transmission. Inhibition of spinal NGF expression effectively protected the heart from myocardial IRI, which may imply a new potential therapeutic approach in ischemic heart diseases.
Abstract 426: Stress-induced Kinase Targets of Cardioprotective 3’,4’-dihydroxyflavonol in Injured Myocardium
Authors: Richards Dominic , Yeap Yvonne , Reichelt Melissa , van der Peet Phillip , Williams Spencer J , Woodman Owen L , McLachlan Grant , Ng Dominic
Published: February 2019

3’,4’-dihydroxyflavonol (DiOHF) is a synthetic flavonol in a class of phytochemicals known as flavonoids can have beneficial biological properties. Previous studies revealed that intravenous administration of DiOHF immediately preceding myocardial reperfusion potently reduced infarct size in anaesthetised sheep that was comparable to ischemic preconditioning and the protective effects of DiOHF were recapitulated
ex vivo
during ischemia/reperfusion (I/R) of Langendorff-perfused rat hearts and
in vitro
on isolated cardiac myocytes. These studies highlight the therapeutic potential of DiOHF, with derivatives recently entering Phase II trials for the reduction of ventricular injury and contractile dysfunction following myocardial infarction (NCT02557217). In our current study, we confirmed potent cytoprotective effects of DiOHF in preventing apoptotic and necrotic death of primary rat cardiomyocytes. In addition, we revealed potent anti-hypertrophic effects in cardiomyocytes stimulated with alpha and beta-adrenergic agonists. In comparison with structurally similar compounds, fisetin, quercetin and dihydroxyflavone, DiOHF exhibited enhanced anti-hypertrophic and protective properties. The molecular targets of DiOHF that underpin it’s beneficial effects are of immense interest as they aid clinical development of derivative compounds, rational design of new compounds with biological activity and provide novel insights into the regulatory mechanisms that define the protected myocardium. In exploring the DiOHF mechanisms of action, we had previously reported DiOHF inhibited Ca2+/calmodulin dependent protein kinase II (CaMKII) activity in
in vitro
kinase assays and in cultured myoblasts. Here, we used resin-immobilized DiOHF for affinity purification from heart tissue lysates and confirmed direct drug-interaction with CaMKII/p-CaMKII from injured rat myocardium (I/R). In addition, we revealed DiOHF interaction and direct inhibition of apoptosis-signal regulated kinase (ASK1) from I/R rat hearts. Our ongoing studies will define whether flavonol inhibition of CaMKII and ASK1 defines protective benefits of DiOHF in the injured myocardium.
Abstract 431: KLF15 Regulates the Circadian Susceptibility to Ischemia Reperfusion Injury in the Heart
Authors: Li Le , Li Hui , Tien Chih-Liang , Zhang Rongli , Liao Xudong , Jain Mukesh K. , Zhang Lilei
Published: February 2019

The onset and the injury of heart attacks both show a circadian rhythmicity with a peak during the sleep to active transition. Studies using cell type specific clock mutant demonstrated the intrinsic varying susceptibility of the cardiomyocytes to the ischemia reperfusion (I/R) injury in a time-of-the-day dependent fashion, however, the molecular mechanisms remain unclear. Transcription factor KLF15 expresses in a circadian fashion and is significantly reduced in ischemia cardiomyopathy in human and in mice, but its role in the cardiac I/R injury is unknown. Recently, we show that KLF15 coordinates the diurnal expression of catabolic genes in the heart during the active phase, suggesting it may also be involved in regulating the cardiac reactive oxygen species (ROS), which is not only a byproduct of catabolism but also the main injury during reperfusion. Here we show that cardiomyocyte specific KLF15 deficient mice have exaggerated I/R injury in vivo during the sleep to active transition when KLF15 expression is at peak, but not during the active to sleep transition, demonstrating its critical role in governing the circadian rhythmicity of myocardial injury. We found acute KLF15 deficiency in the primary cardiomyocytes is associated with increased ROS and exaggerated susceptibility to oxidative stress, which can be rescued by a MnSOD mimetic Tempol, but not by several other anti-oxidants. We further demonstrate that KLF15 deficiency in the cardiomyocytes in vitro and in vivo are both associated with increased mitochondrial acetylation, including MnSOD acetylation at Lysine 122, which leads to reduced MnSOD activity. There is no change in mitochondrial sirtuin SIRT3 level, the main deacetylase for mitochondrial acetylated proteins including MnSOD
K122
, however its co-enzyme NAD
+
level and NAD
+
/NADH ratio are drastically reduced with KLF15 deficiency. Furthermore, NAD
+
precursor NMN rescues the increased susceptibility to ROS in KLF15 deficient cardiomyocytes and I/R injury in vivo. Finally, we show that KLF15 directly regulates nicotinamide phosphoribosyltransferase (NAMPT), the rate limiting enzyme of NAD
+
salvage pathway and the main NAD
+
determinant in the heart. Collectively, our results demonstrate that KLF15 coordinates cardiac metabolism and ROS clearance in a circadian fashion through mitochondrial NAD
+
; loss of KLF15 expression in ischemic cardiomyopathy likely contributes to an enhanced susceptibility to additional I/R insult in a time-of-the-day dependent fashion.
Abstract 434: A Diet Rich in Oleic Acid, as Primary Lipid Source, Attenuates the Progressive Functional Decline in Hypertrophied Hearts During Pathological Stress
Authors: Carley Andrew N , Lewandowski E. Douglas
Published: February 2019

Two major dietary long chain fatty acids (LCFA), oleate and palmitate, display differing capacities to induce transcriptional activation of metabolic genes, lipid trafficking, substrate metabolism, and contractile function in the failing heart. Perfusing isolated failing rat hearts with the unsaturated LCFA, oleate, improves contractile function and restores intracellular lipid dynamics vs. failing rat hearts perfused with the saturated LCFA, palmitate. We therefore investigated whether chronically feeding rats a diet of either high-oleate (as triolein) or high-palmitate (as tripalmitin) could alter the development of heart failure in response to chronic pressure overload induced by transverse aortic constriction (TAC). Following TAC or sham surgery rats were randomized to a diet rich in either triolein or tripalmitin as primary fat source (65% carbohydrate, 20% protein and 15% fat (210 Kcal/kg)). TAC induced similar increases in LV mass independent of diet, however rats fed tripalmitin showed a significant reduction in survival and a decline in ejection fraction and fractional shortening as well as LV dilation, evident at 6 and 10 weeks post TAC (Figure). In contrast, triolein diet attenuated declining systolic function and LV dilation (Figure) and eliminated the otherwise expected elevation of plasma BNP, as seen with tripalmitin diet (50%, P<0.05) after 14 weeks of TAC, indicating differential effects of these fats on both the heart and whole body metabolism and physiology during cardiac stress. The results suggest that a diet rich in oleic acid affords benefits in attenuating the development of cardiac decompensation independent of changes in hypertrophic growth.
Abstract 450: Global Phosphopeptide Analyses Identifies a Profile that Distinguishes Advanced Heart Failure Patients Capable of Cardiac Recovery Following LVAD Unloading
Authors: Tracy Christopher , Makaju Aman , Navankasattusas Sutip , McCreath Lauren , Diakos Nikolaos , Selzman Craig , Drakos Stavros , Franklin Sarah
Published: February 2019

The classical view of the human heart characterizes it as an organ with limited ability to recover and restore itself. Consequently, left ventricular assist devices (LVAD), which provide mechanical circulatory support and profound ventricular unloading, have been used as both a destination therapy as well as a bridge to transplantation in heart failure patients. However, evidence from many prospective studies indicates that a subset of patients with LVAD implants can significantly improve the structure and function of their heart (i.e. “responders”) and undergo LVAD explantation. This intriguing phenomenon provides great promise for heart failure patients, although the underlying mechanisms driving this recovery are largely unknown. To identify global changes in signaling pathways operative in the normal and failing human heart and to distinguish patients who respond to LVAD therapy from non-responders we performed phosphopeptide profiling and label-free quantitation of 38 patients. Our analysis utilized cardiac tissue from 10 donor controls, 6 recovered heart failure patients (responder), and 22 patients that did not respond to LVAD therapy (non-responders). Phosphopeptide enrichment and mass spectrometry-based analyses identified 15,816 unique phosphopeptides, 2,017 of which were shared between all samples. Label-free quantitation and bioinformatic analysis further classified 288 peptides [≥ 2 fold change (p<0.01)] within this dataset that distinguish control tissue from those in heart failure. Most intriguing however, was our assessment of the phosphopeptide profile of heart failure patients at the time of LVAD implantation which, using a signature of 67 peptides [≥ 2 fold change (p<0.01)], allowed complete separation of responder and non-responder samples via statistical analysis. Thus, this panel of 67 phosphopeptides enabled us to determine which patients would experience cardiac recovery following ventricular unloading prior to LVAD implantation. Overall this study characterizes unique changes in phosphoproteins and signaling pathways between the normal and failing human heart and specifies those which define hearts capable of cardiac recovery which may guide strategies to improving current heart failure therapies.
Abstract 453: Young Adult Female Dahl Salt-Sensitive Rats with Heart Failure with Preserved Ejection Fraction have a Distinct Survival Advantage over Age-Matched Afflicted Males
Authors: Angert David W , Kilfoil Peter , De Couto Geoffrey , Aynaszyan Stephan , Cho Jae H , Echavez Antonio , Valle Jackelyn , Jaghatspanyan Eva , Marban Eduardo
Published: February 2019

Introduction:
Cardiovascular disease is the #1 killer of women. Heart failure with preserved ejection fraction (HFpEF) represents ≥50% of HF patients, and affects women ~2x more than men. With no treatment strategies showing decreased mortality, this indicates a critical unmet medical need.

Objectives:
To identify sex difference in HFpEF, we are establishing the female model of HFpEF in the Dahl salt-sensitive (DS) rat. We aim to compare male (M) and female (F) DS rats with HFpEF to identify sex-related differences in underlying mechanisms of HFpEF, for the first time.

Methods:
7-week-old DS rats of both sexes are randomly assigned to low-salt (LS; control) or high-salt (HS; 8%) diets. At 7, 14 and 18-weeks of age, rats undergo echocardiography. The endpoint for LS and HS groups is 18-weeks, when HS diet groups have developed diastolic dysfunction and HFpEF. Invasive hemodynamics are performed prior to euthanasia.

Results:
HS (M) and (F) DS rats show a significant increase in systolic (M: 233±20; F: 243±15 bpm vs control; p<0.001) and diastolic (M: 186±18; F: 183±25 bpm vs control; p<0.001) blood pressure at 18-weeks, with no change in ejection fraction. Normalized LV wall thickness is differentially increased between sexes, with anterior wall thickness (systole) greater in (M) (M:F = 1.6-fold; p<0.001), but posterior wall thickness (diastole) greater in (F) (F:M = 1.5-fold; p<0.001), indicating structural differences. Normalized heart weight/tibia length in HS vs LS diets is increased in (F) (F: 0.39 vs. M: 0.23; p<0.001), indicating increased cardiac hypertrophy in (F). Hemodynamics show increased normalized end-diastolic pressure volume relationship in (F) (F: 1.01 vs. M: 0.64; p<0.01). Although (F) DS rats with HFpEF show increased cardiac hypertrophy and worse diastolic dysfunction compared with age-matched (M) DS rats with HFpEF, Kaplan-Meier survival analysis shows an 18-week mortality rate significantly greater in (M) (~50%) vs. (F) (~16%).

Conclusion:
This study characterizes the female DS model of HFpEF, and elucidates worsening (F) cardiac dysfunction vs. (M) at 18-weeks of age, with provocative results showing significantly decreased morbidity and mortality among females at the same time-point, indicating cardioprotective effects.
Abstract 456: YAP-TEAD1-OSM Amplification Loop Plays a Critical Role in Mediating Cardiomyocyte De-differentiation
Authors: Mizushima Wataru , Ikeda Shouhei , Zhai Peiyong , Sadoshima Junichi
Published: February 2019

The Hippo pathway regulates organ size by inhibiting cell proliferation and promoting apoptosis through negative regulation of YAP, a transcription factor co-factor. Suppression of Hippo and activation of YAP promotes myocardial regeneration after myocardial infarction. However, our recent results suggest that Hippo downregulation and activation of YAP induce de-differentiation of cardiomyocytes (CMs) through activation of genes regulated by TEAD1, which in turn induces contractile dysfunction in the presence of pressure overload (PO). Since oncostatin M (OSM), a member of the interleukin-6 family of cytokines, is a mediator of CM de-differentiation, we evaluated whether OSM plays an important role in mediating CM de-differentiation in WW45 cKO mice, a mouse model of Hippo downregulation, during PO. RNA sequencing analyses showed that OSM receptors (OSMRs) are upregulated in WW45 cKO mice in response to PO. Immunoblot analyses showed that both OSM and OSMR are upregulated by PO and that their levels are further increased in WW45 cKO mice. Upregulation of OSM and OSMR was also observed in adult cardiomyocytes (ACM) isolated from WW45 cKO mice after PO. Downregulation of YAP and TEAD1 significantly decreased OSM reporter gene activity
in vitro
, suggesting that OSM and OSMR are downstream targets of the YAP-TEAD1 pathway in CMs. Treatment of mice with OSM increased the levels of MYH7 and ACTA2, as well as YAP and TEAD1, in ACM at baseline, indicating the existence of an amplification loop composed of YAP, TEAD1 and OSM to promote CM de-differentiation. Suppression of any component of the amplification loop inhibited CM de-differentiation and cardiac dysfunction in WW45 cKO mice in response to PO. These results indicate that the YAP-TEAD1-OSM loop plays a critical role in mediating CM de-differentiation.
Abstract 467: p53 Stabilized iPS Derived Cardiomyocytes Promote Myocardial Repair
Authors: Kannappan Ramaswamy , Turner James F , Rajasekaran Vasanthi , Zhang Jianyi
Published: February 2019

Rapid and continuous culturing of cells leads to accumulation of oxidative stress and DNA damage. These heterogeneous mixtures of healthy and damaged functionally incompetent cells (FIC) are not suitable for transplantation. We hypothesized that selecting only the healthy cells and use for cell would improve engraftment rate and cardiac function. Utilizing the discriminating nature of p53, inducing apoptosis in damaged cells while retaining cell cycle in healthy cells, we tested whether stabilizing p53 can retain only the healthy cells in the culture. p53 in iPS cultures were stabilized using small-molecule nutlin-3a. Cells that didn’t die due to p53 stabilization were collected and differentiated into cardiomyocytes. The markers for cell stress such as the ROS, superoxide and DNA damage were significantly reduced in p53S cells. Following differentiation p53S-CMs were characterized by high expression of CM markers Nkx2.5, Gata4, TnI, MYL2, MLYK, KCNH2 and CAMK2B. Efficiency of p53S-CM to engraft and remuscularize the injured myocardium were tested in small animal MI model. After one week of cell transplantion cardiac function, infarct size and engraftment rate of cells were comparable between p53S-CM and control-CM recieved groups. At week four significant improvement in cardiac function and reduction in infarct size were observed in both groups. However, improvement in these parameters were more prominent in p53S-CM groups. Macrophage analysis revealed enhanced recruitment of anti-infalmatory M2 macrophages in p53S-CM groups and inflammatory M1 macropaheges in control-CM groups at the injection site. Moreover, p53S-CM exosomes induced predominant M2 polarization while control-CM exosomes favored M1 polarization of RAW264.7 macrophages. Our data clearly shows functionally competent cells can be isolated from a population of heterogeneous cells by stabilizing p53. The p53S-CMs showed superior performance in in vitro and in vivo. Therefore, selecting healthy cells by stabilizing p53 would better repopulate the deteriorating myocardium and improve cardiac performance.
Abstract 469: Transient Introduction of miR-294 in the Heart Promotes Cardiomyocyte Cell Reentry After Injury
Authors: Kurian Justin , Borden Austin , Troupes Constantine , Yang Yijun , Nickoloff Emily , Mohsin Sadia , Houser Steven , Kishore Raj , Khan Mohsin
Published: February 2019

Rationale:
Embryonic heart is characteristic of rapidly dividing cardiomyocytes required to build a working myocardium. Cardiomyocytes retain some proliferative capacity in the neonates but lose most of it in adulthood. Consequently, a number of signaling hubs including microRNAs are altered during cardiac development. Embryonic stem cell cycle (ESCC) miRs are a class of microRNAs exclusively expressed during developmental stages but their effect on cardiomyocyte proliferation and heart function has not been previously studied.

Objective:
To determine whether miR-294 promotes cardiomyocyte cell cycle reentry enhancing cardiac repair after myocardial infarction.

Methods and Results:
miR expression analysis in the heart during development revealed elevated levels of miR-294 in the prenatal stages but was lost in the neonate and adult heart as confirmed by qRT-PCR and in situ hybridization. Neonatal ventricular cardiomyocytes (NRVMs) treated with miR-294 mimic showed elevated expression of Ki67 (7-fold), p-histone 3 (7.5-fold) and Aurora B kinase (11.8 fold) as confirmed by immunocytochemistry compared to control cells. Similar results were confirmed in adult cardiomyocytes with p-histone staining and mRNA analysis. Moreover, miR-294 enhanced oxidative phosphorylation and glycolysis in NRVMs as measured by seahorse assay. Mechanistically, array analysis revealed upregulation of cell cycle markers including blunting of negative regulators as confirmed by qRT-pCR and immunoblot analysis. Next, an inducible miR-294 AAV-9-αMHC vector was delivered to mice fed dox chow for 2 wks following myocardial infarction. Increased EF, FS and hemodynamic parameters together with decreased infarct size and apoptosis was observed 8 wks after MI. Myocyte proliferation increased in miR-294 hearts analyzed by Ki67, p-H3 and AurB expression parallel to increase in small myocyte number in the heart. Isolated adult myocytes from miR-294 hearts showed increased EdU+ cells and upregulation of cell cycle markers/miR targets 8 wks after MI.

Conclusion:
Ectopic expression of miR-294 recapitulates developmental signaling and phenotype in cardiomyocyte promoting cell cycle reentry that leads to augmented cardiac function in mice after myocardial infarction.
Abstract 471: Development of a Cardiomyocyte Targeting Delivery System Utilizing Cardiosphere-Derived Cell Exosomes
Authors: Mentkowski Kyle I , Lang Jennifer K
Published: February 2019

Research has shown that treating the heart with stem cell populations, including cardiosphere-derived cells (CDCs), post myocardial infarction stimulates regeneration, angiogenesis, and functional improvement. While this treatment has shown promise in early stage clinical trials, there remains a gap in the ability to efficiently deliver tissue-specific agents directly to the heart while avoiding nonspecific delivery to other organs. Our aim was to develop an efficient delivery system that can target cardiomyocytes and transport drugs, siRNA, and/or miRNA to aid in the treatment of cardiovascular diseases.

Methods:
Lamp-2b was cloned with cDNA from C2C12 cells and ligated downstream of the CMV promoter in a lentiviral transfer plasmid. Primers designed to encode a cardiomyocyte targeting peptide were used to introduce the targeting ligand between XhoI and BspEI at the N terminus of Lamp-2b forming the final vector (LV-CMP). We subsequently generated CMP lentivirus by triple transfection of LV-CMP with helper plasmids pLP/VSVG and psPAX2 into 293T cells. CDCs were transduced at 1 MOI in the presence of polybrene. Exosomes were isolated from infected and non-infected CDCs and labelled with a nucleic acid dye. Cultured mouse cardiomyocytes were incubated with 1 ug of fluorescent labeled CDC-exosomes or CMP CDC-exosomes for 24 hours then imaged.

Results:
To achieve exosomal cardiomyocyte targeting, we engineered CDCs to express Lamp-2b, an exosomal membrane protein, fused to a cardiomyocyte specific peptide. Primary cardiomyocytes showed a 3.8-fold increase in uptake of targeted CMP CDC-exosomes in vitro when compared with their non-engineered CDC control, establishing the efficacy of our system and laying the groundwork for further experiments to assess the efficiency of cardiac localization and cardiomyocyte uptake in vivo.

Conclusions:
Cardiomyocytes show enhanced in vitro uptake of CDC-derived exosomes engineered to express a cardiomyocyte targeting peptide fused with Lamp-2b. Improving exosomal uptake by cardiomyocytes following myocardial infarction would allow for improved delivery of beneficial drug and gene therapies and may result in an increase in viable myocardium and improved functional capacity of the heart.
Abstract 485: Enhanced Chaperone Mediated Autophagy in Cardiomyocytes Ameliorates Pathology Induced by Hypoxic and Proteotoxic Stresses
Authors: Ghosh Rajeshwary , Pattison J S
Published: February 2019

Rationale:
Protein degradation pathways play a critical role in maintaining cardiac homeostasis. Chaperone mediated autophagy (CMA) is a protein degradation pathway unique to mammalian cells, but little is known about CMA in cardiac disease. Preliminary studies in our lab showed increased CMA activity in mouse hearts subjected to MI (1.81 fold) and TAC surgery (3.5 fold), as well as, in hearts from mutant CryAB
R120G
transgenic mice (3 fold). Thus, we hypothesized that CMA plays a critical role in hypoxia- and proteotoxicity-induced cardiac stresses. CMA selectively targets substrate proteins for lysosomal degradation using CMA-specific lysosome membrane protein type 2a (LAMP2a) receptor. LAMP2a is both necessary and sufficient for CMA activity.

Methods:
An adenovirus and a siRNA were created to overexpress and silence LAMP2a levels to study the gain and loss of CMA in neonatal rat ventricular cardiomyocytes (NRVMs). Two models of cardiomyocyte stress were employed: 1) a hypoxic stress model that exposed NRVMs to CoCl
2
, a hypoxia mimetic agent; and 2) a proteotoxic model where mutant CryAB
R120G
, a missense mutation of αB-crystallin, was expressed causing the accumulation of insoluble protein aggregates. A more specific measure of CMA activity was also determined in lysosomal fractions of NRVMs.

Results:
The LAMP2a adenovirus and siRNA showed successful increase and knockdown of LAMP2a levels in NRVMs, respectively. CoCl
2
-induced hypoxia significantly increased CMA activity in NRVMs (26%). LAMP2a overexpression further augmented CoCl
2
-induced CMA activity (55%) and increased the percent of CMA-active lysosomes. LAMP2a siRNA blunted the CoCl
2
-induction of LAMP2a protein levels (65%) and silenced CMA activity in intact lysosomes. Further, CoCl
2
increased apoptosis which was rescued by enhanced CMA activity as shown by TUNEL staining. Thus, CMA is regulated by hypoxic stress and modulates cardiac cell survival. In a proteotoxic model, CryAB
R120G
and LAMP2a co-infection decreased CryAB
R120G
protein levels and insoluble aggregate pathology. Our data suggest that CMA may be cardioprotective against hypoxic and proteotoxic stresses.

Impact:
Defining the role of CMA in the heart could open new therapeutic pathways for the treatment of heart failure.
Abstract 492: Intra Mural Aortic Hematoma: An Unusual Case Presenting With Acute Limb Ischemia
Authors: Salagundla Nethuja , Murray Dylan R , Asm Islam , Parker George H , Salwan Anu
Published: February 2019

A 50 YO F with PMH of HTN, HLD, DM2, presented with claudication of right lower extremity with cyanotic changes of her toes for past few months, with increasing pain and discoloration. CT Angio showed ulcerated plaque of abdominal aorta and 1.5 cm dissection and stenosis of right common iliac artery. Intervention done with urgent stent placement. Patient returned 5 days later with worsening of pain and cyanosis of right toes with increasing symptoms of heaviness and claudication with about 1-2 blocks. Physical examination suggestive of discoloration of right foot toes, audible pedal pulses on right. Repeat Ct angio showed focal intramural hematoma and dissection within the right common iliac artery just above the stent, with 75% stenosis. Possibly from rupture of ulcer from surgical manipulation. Vascular surgeon and Interventional radiologist, both agreed on stent graft placement based on current guidelines. Patient underwent procedure without complications, pain and cyanosis improved within in next few days. Discussion: Intramural hematoma is currently defined as a hematoma in the medial layer without evidence of an intimal tear, which would otherwise indicate aortic dissection. The exact mechanism of intramural hematoma is unknown, 2 proposed mechanisms are penetrating atheroslerotic lesion or rupture of vasovasorum. Management is based on location; Type A is a surgical emergency, whereas type B is managed medically or by endovascular intervention. It should be noted that penetrating aortic ulcers and intramural hematomas can occur in the distal abdominal aorta and proximal bifurcation, and that these lesions can be managed successfully with endovascular intervention.
Abstract 497: Rtf1 Regulates Cardiac Development and Function
Authors: Chen Jaunian , Langenbacher Adam D , Lu Fei , Ren Vincent , Wang Yibin , Gao Chen
Published: February 2019

Highly regulated transcriptional control of cardiac gene networks is critical for heart development and function. Rtf1 is a critical regulator of multiple transcription processes including elongation and co-transcriptional histone modification. Rtf1 ablation in zebrafish and mice eliminates the cardiac progenitor population, producing embryos without hearts, and knockdown of Rtf1 in neonatal rat ventricular myocytes decreases the expression of sarcomere component genes, suggesting that Rtf1 is indispensable for both establishing the myocardial lineage and maintaining normal physiological homeostasis in differentiated cardiomyocytes. To explore the function of Rtf1 in the adult heart, we generated an inducible knockout of Rtf1 in the adult myocardium. Loss of Rtf1 function in adult cardiomyocytes results in left ventricular systolic dysfunction and pathological features of heart failure. The Rtf1 deficient hearts exhibit a gene expression profile characteristic of heart failure, and display disrupted myofibrils and cell-cell junctions. Intriguingly, and in line with Rtf1’s established role in promoting histone H2B ubiquitination, diminished H2BK120 ubiquitination was also observed in Rtf1 deficient adult hearts. Collectively, our findings show that Rtf1 and Rtf1 mediated H2BK120 ubiquitination are essential epigenetic regulators of both myocardial lineage determination during development as well as maintaining cellular homeostasis, integrity and function in mature cardiomyocytes.
Abstract 503: Modeling Premature Cardiac Aging by Induced Pluripotent Stem Cell From a Patient With Hutchinson-Gilford Progeria Syndrome
Authors: Monnerat Gustavo , Brunswick Tais , Asensi Karina , Santos Danubia , Andrade Raiana , Mesquita Fernanda , Albuquerque João Paulo , Ferreira Raphaela , Simões João , Muniz Mariana , Wendit Camila , Velasquez Erika , Dumont Gilberto , Nogueira Fabio , Campos de Carvalho Antonio C
Published: February 2019

Background:
Hutchinson-Gilford Progeria Syndrome (HGPS) is an extremely rare genetic disorder characterized by accelerated aging and high incidence of cardiovascular complications and metabolic alterations. However, the underlying mechanisms of this syndrome are not fully understood.

Methods and Results:
This study modelled HGPS using cardiomyocytes generated from induced pluripotent stem cells (iPSc) derived from a patient affected by the syndrome, characterizing the molecular and biophysical alterations found in cardiomyocytes obtained from three distinct differentiation protocols run in parallel with a control iPSc. Electrophysiology recordings were performed with intracellular microelectrodes and the Progeria cardiomyocytes fired action potentials similar to those from control iPSc-derived cardiomyocytes. High resolution respirometry performed on Oroboros system in isolated cardiomyocytes showed that Progeria cardiomyocytes have a tendency to decrease the oxygen consumption under basal condition and after FCCP, when compared to control cardiomyocytes (P=0.06). Furthermore, HGPS cardiomyocytes produced less ROS under basal and after 100uM Hydrogen peroxide treatment. However, mitotracker analysis shows no difference on mitochondrial content. Electron tomography and 3D reconstruction analysis suggest structural abnormalities in the mitochondria of Progeria cardiomyocytes. Proteomics analysis, performed with Liquid Chromatography tandem mass spectrometry (LC-MS/MS) in a high-resolution system (Q-Exactive Plus, Thermo Fischer), shows differential protein expression between Progeria (183 unique proteins) and Control (225 unique proteins) IPSc - derived cardiomyocytes.

Conclusions:
Our work demonstrate that iPSc- derived cardiomyocytes from Progeria patients have significant alterations in cellular respiration and protein expression.
Abstract 520: Overexpression of a Non-muscle RBFOX2 Splice Isoform Induce Cardiac Arrhythmias in Myotonic Dystrophy
Authors: MISRA CHAITALI , BANGRU SUSHANT , PARKER DARREN J , KOENIG SARA , LUBBERS ELLEN , HEDHLI JAMILA , COOPER THOMAS A , DOBRUCKI WAWRZYNIEC L , MOHLER PETER , KALSOTRA AUINASH
Published: February 2019

Myotonic dystrophy type 1 (DM1) is a dominantly inherited neuromuscular disease caused by a CTG repeat expansion in 3’-UTR of
DMPK
gene. DM1 affects multiple tissues, but cardiac dysfunctions are the second leading cause of death which often include conduction defects and arrhythmias. The best characterized pathogenic mechanism of DM1 is toxic gain-of-function of expanded CUG repeat (CUG
exp
) RNA that accumulates to form ribonuclear foci causing sequestration of MBNL and overexpression of CELF1 family of splicing factors. However, loss of MBNL or gain of CELF1 activity does not explain the cardiac phenotypes observed in DM1. Here we report that steady-state protein levels of RBFOX2, a critical splicing regulator, are drastically upregulated in DM1 heart tissue. This is accompanied by aberrant skipping of a muscle-specific 43bp exon in
RBFOX2
transcript, resulting in selective up-regulation of the non-muscle RBFOX2 splice isoform in adult cardiomyocytes. We demonstrate that expression of CUG
exp
RNA in DM1 affects RBFOX2 in two distinct ways: reduced expression of a subset of microRNAs causes de-repression of RBFOX2 protein production; and CELF1 overexpression promotes skipping of the muscle-specific exon of
RBFOX2
. Remarkably,
tet
-inducible overexpression of the non-muscle RBFOX2 isoform, or CRISPR/
Cas9
mediated deletion of the muscle-specific
RBFOX2
exon in the mouse heart results in prolonged PR and QRS intervals, slower conduction velocity and spontaneous cardiac arrhythmias that mirror human DM1 pathology. Integration of RBFOX2-CLIP with RNA-seq data from cardiomyocytes of mice expressing the non-muscle RBFOX2 isoform identified a core network of mRNA splicing defects in genes encoding sodium, potassium, and calcium ion channels and key excitation-contraction coupling proteins that are similarly misspliced in hearts of DM1 patients. Thus, we have uncovered a central role for RBFOX2 isoform switching in DM1 cardiac pathogenesis and identified the molecular mechanisms that may alter electrophysiological properties and thereby induce cardiac arrhythmias in the DM1 heart.
Abstract 546: GJA1-20k Protects the Heart From Ischemic Injury by Inducing Mitochondrial Biogenesis and Metabolic Quiescence
Authors: Basheer Wassim A , Fu Ying , Xiao Shaohua , Hong TingTing , Shaw Robin M
Published: February 2019

Connexin 43 (Cx43) is a cell-cell communication gap junction protein that is encoded by the GJA1 gene and is expressed in all organ systems. It was recently found that the GJA1 mRNA undergoes alternative translation to generate N-terminally truncated isoforms, of which GJA1-20k is the most abundant. We have recently identified that GJA1-20k has a strong tropism for mitochondria and that GJA1-20k overexpression is sufficient to rescue mitochondrial localization to the cell periphery, limiting organelle network collapse upon exposure to oxidative stress. Given the protective role of GJA1-20k on mitochondrial network and the importance of preserving mitochondrial integrity in preventing cardiac ischemic injury, we therefore asked the question whether exogenous GJA1-20k can increase myocardial survival when subjected to stress. Using high resolution confocal imaging, we find that H
2
O
2
-induced oxidative stress in cardiomyocytes causes an upregulation of GJA1-20k independent of full length Cx43 expression. Furthermore, we find that GJA1-20k is upregulated and preferentially enriched in mitochondria after acute ischemia/reperfusion injury in isolated mouse hearts. We also find that exogenous GJA1-20k, when delivered by adenovirus to isolated adult mouse cardiomyocytes, was sufficient to improve cell survival and viability during H
2
O
2
-induced oxidative stress. When delivered in vivo using an Adeno-associated virus serotype 9 (AAV9), GJA1-20k exhibited potent cardioprotective effects by reducing ischemic injury size in a mouse model of myocardial infarction. AAV9-mediated gene transfer of GJA1-20k also resulted in increased cardiac mitochondrial content as observed by electron microscopy. Yet 20k-increased mitochondrial content in cardiomyocytes is associated with reduced mitochondrial membrane potential as well as respiration as measured by Seahorse assay, indicating a quiescent metabolic state resistant to stress. In conclusion, we have identified GJA1-20k as a stress response protein that increases mitochondrial biogenesis and reduces metabolic reactivity, providing powerful cardioprotection against ischemic insults.
Abstract 548: Evolutionarily Conserved Functions for Valosin Containing Protein (VCP) in Cardiac and Skeletal Muscle Reveal Mechanistic Insights into Multisystem Proteinopathy
Authors: Brody Matthew J , Vanhoutte Davy , Viswanathan Meera C , Nguyen Tran , Maillet Marjorie , York Allen J , Sargent Michelle A , Cammarato Anthony , Molkentin Jeffery D
Published: February 2019

Valosin Containing Protein (VCP)/p97 is a AAA-ATPase with functions in vast cellular protein quality control processes, including targeting of misfolded or aggregated proteins for degradation by the ubiquitin proteasome system and autophagy. Mutations in VCP cause a multisystem degenerative proteinopathy disorder that includes pathologies of the nervous system, skeletal muscle, bone, and heart. However, the molecular function of VCP in myocytes is unknown. We generated cardiomyocyte-specific transgenic mice overexpressing wildtype VCP or a VCP
K524A
mutant with deficient ATPase activity. Mice overexpressing wildtype VCP exhibit normal cardiac structure and function while mutant VCP overexpressing mice develop cardiomyopathy and have elevated levels of ubiquitinated proteins in the heart. Additionally, we generated transgenic flies overexpressing wildtype VCP or VCP
K524A
in muscle. Flies overexpressing the VCP ATPase-deficient mutant have reduced flight ability at two days of age and are unable to fly at seven days of age, suggesting conserved indispensable homeostatic functions for VCP in heart and skeletal muscle. Moreover, mouse hearts and
Drosophila
indirect flight muscle overexpressing the ATPase-deficient VCP mutant exhibit profound ultrastructural abnormalities consistent with dysregulation of proteostasis. Extensive proteomics in
Drosophila
and in mouse heart identified conserved interactions of VCP with protein complexes that suggest unique functions for VCP in regulating novel quality control pathways in muscle. These data and novel regulatory relationships will be presented, which implicate important and evolutionarily conserved functions for VCP and suggest molecular mechanisms that underlie the molecular etiology of multisystem proteinopathy disorders.
Abstract 549: Interleukin-6 Trans-Signaling in Acute Myocardial Infarction in Male BALB/c Mice
Authors: Holland Nathan A , Lust Robert M , Wingard Christopher J , Tulis David A
Published: February 2019

Interleukin-6 (IL-6) is a pleiotropic cytokine historically associated with development and/or maintenance of cardiovascular disease (CVD). Despite this long-standing association, the discrete roles of IL-6 on the pathogenesis or severity of CVD and notably acute myocardial infarction (AMI) remain unclear. Dogma contends that IL-6 mediates effects largely through direct interaction with a membrane-bound IL-6 receptor (IL-6R) on leukocytes and hepatocytes. Intriguingly, identification of a soluble receptor for IL-6 (sIL-6R) has invigorated study into a regulatory role of IL-6 trans-signaling (IL-6trans) in CVD pathogenesis. IL-6trans provokes signal transduction in cells lacking the membrane-bound receptor, including notably cardiomyocytes, and ultimately activates STAT3 gene transcription and stabilizes mitochondrial function, thereby promoting cardioprotection. In this study we hypothesized that IL-6trans plays a crucial role in the injury response to AMI by increasing circulating IL-6 and sIL-6R and inducing cardioprotection via STAT3. To test this hypothesis, male BALB/c mice were subjected to acute ischemia (30 min) of the LAD coronary artery (to mimic AMI) with/without reperfusion and with/without inclusion of a pre- or post-ischemic conditioning event in order to determine regulatory involvement of IL-6trans in acute cardioprotection. Following surgery, ischemic regions of left ventricle (LV) and sera were analyzed for IL-6, sIL-6R, and activated (phosphorylated) STAT3. Results show that AMI led to increases in serum IL-6 (p=0.0053) and sIL-6R (p=0.0023) as well as in LV phosphorylated (Tyr705) STAT3 (p=0.0059) compared to naïve LV tissues. Preliminary data from ischemic pre- and post-conditioning regimens were independently associated with increases in IL-6trans demonstrated by trending increases in LV STAT3 phosphorylation (Ser727, Tyr705) compared to naïve controls. These inclusive data on IL-6trans suggest it serves a biologically significant intrinsic role in mediating acute protection following AMI. We anticipate that continued investigation will firmly establish IL-6trans as a unique protective pathway that could be targeted in order to improve morbidity and mortality of AMI patients.
Abstract 576: Nrf2 is a Key Regulator on Puerarin Preventing Cardiac Hypertrophy and Upregulating Metabolic Enzymes Ugt1a1 and Ugt1a9 in Rats
Authors: Hou Ning , Zhao Ganjian , Cai Shaoai , Liu Xiawen , Li Aiqun , Huang Yin , Li Lirong , Luo Chengfeng
Published: February 2019

Previous evidence suggested that puerarin may attenuate cardiac hypertrophy; however, the potential mechanisms were undetermined. Moreover, the use of puerarin is limited by severe adverse events, including intravascular hemolysis. This study used a rat model of abdominal aortic constriction (AAC) -induced cardiac hypertrophy to evaluate the potential mechanisms underlying the attenuating efficacy of puerarin on cardiac hypertrophy as well as the metabolic mechanisms of puerarin involved. We confirmed that puerarin (50 mg/kg/d) significantly attenuated cardiac hypertrophy, upregulated Nrf2 and decreased Keap1 in the myocardium. Moreover, puerarin significantly promoted Nrf2 translocation to the nucleus in parallel with the upregulated downstream proteins including heme oxygenase-1, glutathione s-transferase p-1 and NAD(P)H: quinone oxidoreductase-1. Similar results were obtained in neonatal rat cardiomyocytes (NRCMs) treated with angiotensin II (1 μM) and puerarin (100 μM), while the silencing of Nrf2 abolished the antihypertrophic effects of puerarin. The mRNA and protein levels of UGT1A1 and UGT1A9, enzymes for puerarin metabolism, were significantly increased in the liver and heart tissues of AAC rats and angiotensin II-treated NRCMs. Interestingly, the silencing of Nrf2 attenuated the puerarin-induced upregulation of UGT1A1 and UGT1A9. The results of chromatin immunoprecipitation-qPCR indicated that the binding of Nrf2 to the promoter region of UGT1A1 or UGT1A9 was significantly enhanced in puerarin-treated cardiomyocytes. These results suggest that Nrf2 is the key regulator of antihypertrophic effects and the upregulation of the metabolic enzymes UGT1A1 and UGT1A9 of puerarin. This autoregulatory circuits between puerarin and Nrf2-induced UGT1A1/1A9 are beneficial to attenuate adverse effects and maintain the pharmacological effects of puerarin.
Abstract 582: Determining and Modeling of the Cardiac Protein-Protein Interaction Network of the Inotropic Factor S100A1 by AP-MS/MS
Authors: Egger Michael , Jebessa Zegeye , Wade Rebecca , Katus Hugo A. , Busch Martin , Most Patrick
Published: February 2019

Background:
S100A1 is an EF-hand calcium (Ca
2+
) sensor protein with predominant expression in the mammalian heart. Although its outstanding influence on cardiac performance is well described, only few target molecules are known so far, such as the sarcoplasmic reticulum Ca
2+
ATPase (SERCA2a).

Objective and Results:
The discrepancy between the known interactors and the diversity of S100A1`s functions brings up the question which key targets are undetected so far and can, in addition to the known ones, explain the importance of S100A1 for the heart function. S100A1 knock-out (SKO
-/-
) mouse heart extracts and lysates of isolated SKO
-/-
cardiomyocytes were subjected to HPLC S100A1 affinity-purification (AP) columns coupled to tandem mass spectrometry (MS) followed by network modeling of the interactome, to identify novel and to confirm previously known targets in the heart. Human recombinant S100A1 protein AP columns were used to trap EGTA- and Ca
2+
-dependent interactions. Subsequent MS and computational analyses revealed more than 90 novel cardiac interactors for S100A1 in a strict Ca
2+
-dependent manner, while previously known targets were confirmed.

We showed that helix 4 of S100A1 (S100A1ct) alone can improve main parameters for the heart performance and might thereby function as a therapeutic biologic. Investigating the molecular mechanisms of S100A1`s interactions with its target molecules might help to understand this effect and unveil relevant regions for other therapeutic effects. In order to uncover the mechanisms of the various interactions, docking experiments were performed to gain an understanding, which areas of S100A1 and S100A1ct might be relevant for the biological functions on selected targets. Thus we detected a region on SERCA2a where S100A1 as well as S100A1ct might compete with the SERCA2a inhibitor phospholamban and by that may improve the SERCA2a activity. These in silico findings will be combined with experimental investigations of the mode of interaction by Cross-link MS experiments.

Conclusion:
Combining target screening via AP-MS/MS with computer-supported epitope mapping provides a powerful strategy to understand the molecular action of known therapies and by that helps to develop new treatments against heart failure.
Boswellia occulta (Burseraceae), a new species of frankincense tree from Somalia (Somaliland)
Authors: THULIN MATS , DECARLO ANJANETTE , JOHNSON STEPHEN P.
Published: February 2019

The new species Boswellia occulta is described from a small area in the Ceel Afweyn District of Somaliland (northwestern Somalia), where it is locally of considerable socio-economic importance. Although used for frankincense production by many generations of local harvesters, it has been unknown to science until now. Apart from the recently collected type material, it is also known from a sterile and hitherto misunderstood collection made in 1945. The simple-leaved Boswellia occulta is morphologically compared with B. sacra and B. frereana, the two major frankincense-producing species in the region, both with imparipinnate leaves, and it appears to be most closely related to B. sacra. The new species is the only simple-leaved species of Boswellia known outside Socotra.
First survey of Simuliidae (Diptera) from the North of Ceara State, Brazil, with description of a new species and identification keys for the immature stages
Authors: PESSOA FELIPE ARLEY COSTA , VELÁSQUEZ CLAUDIA MARÍA RÍOS , PY-DANIEL VICTOR
Published: February 2019

The first survey of black flies (Diptera: Simuliidae) in Ceará State, Brazil, resulted in the discovery of a new species, Inaequalium maranguapense, for which larvae, pupae, and pharate females are described. This new species was found in a small stream in a mountainous region near the coast. The female has a cibarium lacking the typical central elevation of the genus; the pupa has four gill filaments inflated proximally and arising from the same point; the larva has rectal papillae typically comprised of simple lobes. The following additional species were collected from Ceará State: Chirostilbia acarayense, Ectemnaspis perflava, E. nr. kabanayense, Hemicnetha rubrithorax, H. brachyclada, I. subnigrum, and Psaroniocompsa incrustata. The cibarium of E. perflava is redescribed. Identification keys to the larvae and pupae of black flies from the study area are provided.
A new species of Thinoscatella Mathis, 1979 from China (Diptera: Ephydridae), with an updated key to the world species
Authors: ZHANG JUNHUA , YANG DING
Published: February 2019

The genus Thinoscatella Mathis is recorded from China for the first time. A new species, Thinoscatella tibetensis sp. nov., is described. An updated key to the species of the genus from the world is presented.