bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional characterization of a newly identified LMNA mutant in HL‐1 cardiomyocytes (1073.7)
Authors: Carmosino Monica , Forleo Cinzia , Pisani Francesco , Procino Giuseppe , Torretta Silvia , Favale Stefano , Svelto Maria 
Published: June 2021

A novel mutation in the Lamin A/C gene (LMNA c.418_438dup) was detected in the index patient and in additional family members with diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) and history of sudden cardiac death. The functional characterization of this LMNA mutant was performed in cultured HL‐1 cardiomyocytes expressing EGFP‐tagged wild‐type and mutated LMNA constructs and subjected to confocal microscopy analysis and hypoxic stress conditions in 100% N2 for 8h. Mutated LMNA was clearly expressed in aggregates of different sizes and not uniformly distributed along the nuclear envelope as WT LMNA. Moreover, the mutated LMNA variant causes perturbation in nuclear shape and Nuclear Pore Complexes organization.Of note, we observed that under hypoxic conditions nuclear envelopes expressing mutated LMNA become leaky, leading a nuclear fluorescent marker to escape into the cytoplasm. This indicates that, under cell stressing conditions, the nucleo‐cytoplasmic compartmentalization is affected in cardiomyocytes expressing this LMNA mutation, inducing, as final fatal consequence, cell apoptosis.In conclusion, we not only open new avenues to gain more insights in the pathogenesis of ARVC and to conceive novel therapeutic strategies but we also shed lights on the role of nuclear Lamin A in the physio‐pathology of cardiomyocytes.Grant Funding Source: Supported by Fondo per gli Investimenti della Ricerca di Base‐Rete Nazionale di Proteomica (RBRN07BM
Individual differences in susceptibility to depression and cardiovascular disease comorbidity in a rat model of social stress (1074.10)
Authors: Lombard Calliandra , Melson Michael , Wood Susan 
Published: June 2021

Psychosocial stress precipitates psychiatric disorders (eg, depression) and cardiovascular disease in vulnerable individuals, but underlying mechanisms remain unknown. We previously identified two distinct phenotypic responses to social stress in rats (resident‐intruder model), characterized by either passive coping, assuming defeat within a short latency (SL, 343±7) or by proactive coping behaviors and longer defeat latencies (LL, 571±53). The SL phenotype was associated with endocrine and behavioral characteristics resembling depression and decreased heart rate variability indicating greater cardiovascular disease risk. The present study characterized the impact of stress coping on susceptibility to a depressive‐like phenotype with comorbid hypertension in rats exposed to 7 (30 min/day) social defeat or control manipulations. 24‐hr ECG and pressure telemetry revealed persistent elevations in resting mean arterial pressure (MAP) selectively in the SL phenotype as early as the 4th day (change from day 0: con 0.4 ± 2, SL 7.1 ± 2, LL 2.5 ± 0.9). Interestingly, sucrose intake measured 7 days post stress was negatively correlated with changes in MAP (r= ‐0.34, p=0.03), indicating an association between anhedonia and increased MAP. These studies also sought to determine the impact of these cardiovascular changes on susceptibility to isoproterenol‐induced arrhythmias. These data suggest passive stress coping promotes vulnerability to a depressive‐cardiovascular disease‐like phenotype, while active coping confers resilience. Future studies will utilize this model to identify critical brain regions underlying the pathogenesis of depression‐cardiovascular disease comorbidity.Grant Funding Source: Supported by NARSAD 17830 and 13BGIA 14370026 to SKW
Effect of aging on eNOS‐associated protein:protein interactions throughout the arterial network (1075.8)
Authors: Luttrell Meredith 
Published: June 2021

We previously demonstrated age‐related endothelial dysfunction in oxidative soleus muscle feed arteries (SFA), while endothelial function in glycolytic gastrocnemius muscle feed arteries (GFA) is maintained with age. One mechanism that may account for endothelial dysfunction with age is alterations in eNOS‐associated protein:protein interactions with caveolin‐1 (Cav1) and calmodulin (CaM). Therefore we tested the hypothesis that Cav1:eNOS interaction increases with age while CaM:eNOS interaction decreases with age in SFA and that there would be no change in either protein:protein interaction in aged GFA. Additionally, we assessed the effects of aging on eNOS‐associated protein:protein interactions throughout the arterial network. Co‐immunoprecipitation was used to determine protein:protein interactions. Results show that Cav1:eNOS and CaM:eNOS interactions were not altered by age in SFA or GFA; Cav1:eNOS interaction was greater in GFA than SFA; the phenotype of both Cav1:eNOS and CaM:eNOS interactions was heterogeneous throughout the arterial network; and aging had a non‐uniform effect on both Cav1:eNOS and CaM:eNOS interactions throughout the arterial network. In conclusion, age had no effect on Cav1:eNOS or CaM:eNOS interactions in either GFA or SFA. Also, Cav1:eNOS and CaM:eNOS interactions throughout the arterial network and are non‐uniformly altered with age.Grant Funding Source: Research Supported By: AHA 0765043Y, 4150031 (CRW), AHA 467371 (MJL)
Intravascular pressure stimulates functional KV1.5 surface expression in mesenteric artery smooth muscle cells (1077.4)
Authors: Kidd Michael , Leo M , Narayanan Damodaran , Bannister John , Jaggar Jonathan 
Published: June 2021

Intravascular pressure stimulates arterial depolarization, leading to myocyte voltage‐dependent K+ (KV) channel activation that opposes vasoconstriction. We tested the hypothesis that membrane potential regulates smooth muscle cell KV channel surface expression to modulate Kv channel functionality in mesenteric arteries. Q‐PCR indicated predominant expression of KV1.5 and 2.1 in mesenteric arteries. Contrary to expectations, 70% of total and surface KV1.5 protein was lost within 3 hrs in non‐pressurized arteries. In contrast, KV1.5 or 2.1 mRNA and total and surface KV2.1 protein did not change over the same time course. Bafilomycin, a lysosome inhibitor, and MG‐132, a proteasome inhibitor, both prevented KV1.5 loss. Depolarization (30 mM K+) also inhibited KV1.5 loss and this was blocked by nimodipine, a voltage‐dependent Ca2+ channel blocker. Patch‐clamp studies indicated that KV currents sensitive to DPO‐1, a Kv1.5 inhibitor, were 60% smaller in myocytes isolated from arteries kept at zero pressure than controls. Kv current loss was also blocked by bafilomycin. We also show that physiological intravascular pressure maintains functional Kv1 channel activity in arteries. In summary, data indicate that intravascular pressure inhibits KV1.5 channel degradation to maintain functional surface expression of these proteins in arterial myocytes.Grant Funding Source: NHLBI/NIH
A pharmacologic activator of endothelial KCa channels improves coronary function in the hearts of type 2 diabetic rats (1078.10)
Authors: Mishra Ramesh , Wulff Heike , Cole William , Braun Andrew 
Published: June 2021

Endothelial dysfunction is a common early pathogenic event in patients with type 2 diabetes (T2D) who exhibit cardiovascular disease. In the present study, we have examined the effect of SKA‐31, a positive modulator of endothelial Ca2+‐activated K+ (KCa) channels, on total coronary flow in isolated hearts from Goto‐Kakizaki (GK) rats, a non‐obese model of T2D and age‐matched controls. Total coronary flow and left ventricular developed pressure were monitored simultaneously in spontaneously beating, Langendorff‐perfused hearts. Acute, bolus administrations of bradykinin (BK, 1 μg) or adenosine (ADO, 10 μg) increased coronary flow, and these responses were blunted in diabetic hearts at 10‐12 and 18‐20 weeks of age. In contrast, SKA‐31 dose‐dependently (0.01‐5 μg bolus exposures) increased coronary flow to comparable levels in both control and diabetic rat hearts at both ages. Flow responses to sodium nitroprusside were not different between control and diabetic hearts, suggesting normal coronary smooth muscle function. Importantly, continuous exposure to a sub‐threshold concentration of SKA‐31 (i.e. 0.3 μM) did not alter basal coronary flow or heart rate, but did ameliorate the blunted BK and ADO‐evoked flow responses in diabetic hearts. In summary, these data demonstrate that SKA‐31 is an effective coronary vasodilator in a rat model of T2D exhibiting endothelial dysfunction and metabolic syndrome, and further rescues impaired vasodilatory responses to BK and ADO in the coronary circulation.Grant Funding Source: Supported by CIHR
Antiphospholipid antibodies, necrotic trophoblasts and preeclampsia? (1084.3)
Authors: Lau Sien Yee , Chen Qi , Chamley Larry , Barrett Carolyn , Guild Sarah‐Jane 
Published: June 2021

Preeclampsia is characterized by de novo hypertension, proteinuria and systemic inflammatory response during pregnancy which is preceded by endothelial cell activation. It is triggered by a placental factor(s), one of which may be necrotic trophoblast debris that is shed from the placenta into the maternal blood. Clearance of necrotic trophoblast debris results in endothelial cell activation in vitro and results in a relative increase in blood pressure in vivo. There are also maternal risk factors for preeclampsia, the strongest of which are antiphospholipid antibodies (aPL). We present a two part model observing the interaction between aPL and necrotic trophoblast debris on blood pressure, markers of endothelial cell activation and urinary protein.Pregnant female Wistar rats instrumented with radio‐telemetry blood pressure devices were received necrotic trophoblasts and aPL (n=10) or control antibodies (n=5). Fifteen further rats received only aPL (n=10), or control antibodies (n=5), in the absence of necrotic trophoblasts.Mean arterial blood pressure was not different between rats that received control antibodies or aPL with necrotic trophoblasts. However, heart rate was lower and urinary protein levels were elevated in rats that received necrotic trophoblasts and aPL. Serum levels of interleukin‐6, the proposed spreading factor for endothelial cell activation, were also elevated in rats receiving necrotic trophoblasts.In conclusion, antiphospholipid antibodies, the strongest maternal risk factor in preeclampsia, may interact with necrotic trophoblasts to heighten the systemic inflammatory response which precedes the clinical onset of hypertension in preeclampsia.
Cholesterol regulates both store‐ and agonist‐induced Ca2+ entry in pulmonary arterial endothelium (1089.9)
Authors: Zhang Bojun , Riddle Melissa , Naik Jay , Resta Thomas , Walker Benjimen 
Published: June 2021

Endothelial Ca2+ entry is decreased in pulmonary arteries from rats exposed to chronic hypoxia (CH) (4 wk, PB = 380 torr). In addition, membrane cholesterol (Chol) is diminished in these cells and Chol supplementation restores ATP‐induced Ca2+ entry. Since both agonist‐induced and store‐operated Ca2+ entry (SOCE) are decreased after CH, we hypothesized that both require functional membrane Chol. To test this hypothesis, we administered epicholesterol (EpiCh; epimeric form of cholesterol) or vehicle to pulmonary arterial endothelial cells (PAEC) from control and CH rats to replace native Chol. The efficacy of EpiCh to diminish membrane Chol was confirmed by filipin staining in cultured ECs. EpiCh treatment greatly reduced both cyclopiazonic acid (CPA) ‐induced SOCE and ATP‐induced Ca2+ entry in PAECs from control and CH rats. We next assessed the effect of EpiCh on ATP and CPA‐induced Ca2+ currents in PAEC from control rats using patch clamp. Both EpiCh and La3+ inhibited ATP‐induced current similarly. Although T‐type voltage gated Ca2+ channels contribute to ATP responses, mibefradil (T‐type inhibitor) had no further effect in EpiCh treated cells. Likewise, CPA‐induced current was reduced in cells treated with EpiCh. We conclude that membrane Chol is required for both agonist‐induced and store‐operated Ca2+ entry in PAEC and that reduced Ca2+ seen after CH is possibly due to loss of this key regulator.Grant Funding Source: Supported by NIH grant HL95640
AntimiR‐145 therapy improves right ventricular structure in experimental pulmonary arterial hypertension (1090.1)
Authors: McLendon Jared , Joshi Sachindra , Fewell Jason , Oka Masahiko , McMurtry Ivan , Gerthoffer William 
Published: June 2021

Our previous work shows miRNA‐145 is increased in pulmonary arterial hypertension (PAH) and knockdown of miR‐145 in rats exposed to Sugen‐5416, hypoxia, and normoxia, repairs pulmonary arteriopathy and improves RV function. One explanation for improvements is that partial repair of the arteriopathy reduces pulmonary arterial pressure (and/or increases vascular compliance) which reduces RV afterload. Normal repair mechanisms regulating cardiac structure may then result in reduced RV hypertrophy at the cellular and tissue levels. To test this we measured ventricular weights, RV myocyte cross‐sectional areas and collagen deposition. AntimiR‐145 produced a modest decrease in the RV/LV+S ratio as well as decreased RV weight/body weight ratio. Interestingly, the positive effect on tissue mass was not a result of normalizing RV cardiomyocyte hypertrophy because cellular cross‐sectional area was unaffected by antimiR‐145. These results are more consistent with the response to antimiR‐145 being a reduction in cell number and tissue mass rather than cell atrophy. The therapeutic response also includes beneficial effects on matrix remodeling as shown by reduced collagen deposition. Together the results demonstrate subchronic treatment with antimiR‐145 has beneficial cardiac effects in rats with PAH that result in increased cardiac output as well as partial regression of RV hypertrophy and matrix remodeling.Grant Funding Source: Supported by NIH grant HL097220 to WTG and AHA fellowship 13PRE17070053 to JMM.
High expression of CD147 in endometriosis and its role in regulating apoptosis and migration in human endometrial cells (1093.3)
Authors: Chen Hao , Wang Chaoqun , Jing Aihong , Zhou Xiaping , Cai Zhiming , Chan Hsiaochang 
Published: June 2021

Endometriosis is a common gynecological disease, which contributes to 40% of infertile women in reproductive age. CD147 has been found highly expressed in ectopic endometrium and stimulated the MMPs in human uterine fibroblasts. However, it is poorly understood if and how CD147 affects endometrium epithelial cell migration during the progression of endometriosis. We demonstrate here that the expression of human CD147 was significantly higher in ovarian ectopic endometrium than that of normal endometrium by real‐time PCR. Interfering CD147 function decreased cell migration and cell viability in the normal human uterine epithelial cells (HES). Surprisingly, MMP‐2 expression and activity were not changed when HES treated with anti‐CD147 antibody. Further studies revealed that immunodepletion of CD147 induced apoptosis in HES cells, which led to Caspase‐3 and poly ADP‐ribose polymerase (PARP) activation. The present study demonstrated that CD147 regulates apoptosis and the cell migration in a MMP‐2 independent manner in human endometrial epithelial cells and that abnormally high expression of CD147 in the ectopic endometriosis lesions may contribute to the pathogenesis of endometriosis.Grant Funding Source: Supported by NSFC (31100841) and Shenzhen Projects of Science and Technology (JCYJ20120614085604107)
The promotion of osteogenic differentiation of human adipose‐derived mesenchymal stem cells induced by chitosan‐conjugated gold nanoparticles (1094.1)
Authors: Choi Seon Young , Song Min‐Seok , Ryu Pan‐Dong , Joo Sang‐Woo , Lee So Yeong 
Published: June 2021

Gold nanoparticles are attractive materials for use in biomedicine due to their unique properties. Increasing evidence suggests that several nanoparticles induce differentiation of human mesenchymal stem cells (hMSCs) into osteoblast and adipocyte. In this study, we hypothesized that chitosan‐conjugated gold nanoparticles promote osteogenic differentiation of hMSCs. In order to investigate promoted osteogenic differentiation of hMSCs and related signaling pathway, chitosan‐conjugated gold nanoparticles were added to an osteogenic induction medium for 7, 10, 14 and 21 days. For evaluation of osteogenic differentiation, alizarin red staining, alamar blue assay and quantitative real time PCR were performed. In order to examine specific signaling pathways, immunofluorescence and western blotting assay were performed. Our results demonstrate that nanoparticles increase the deposit of calcium content and the expression of marker genes related to the early stage of osteogenic differentiation in hMSCs at non‐toxic concentrations. These results indicate that nanoparticles promote osteogenesis through Wnt/β‐catenin signaling pathway and may be used as a promoting reagent for bone formation.Grant Funding Source: supported by the National Research Foundation of Korea (2012R1A2A2A01047151)
25‐Hydroxycholesterol inhibits adipogenic differentiation of C3H10T1/2 mouse stem cells through inhibition of PPARγ expression (1094.2)
Authors: Moseti Dorothy , Regassa Alemu , Kim Woo 
Published: June 2021

Oxysterols have been shown to inhibit adipogenic differentiation of mesenchymal stem cells while inducing their osteogenic differentiation. However, the effects of oxysterols on the adipogenic differentiation of C3H10T1/2 mouse stem cells are poorly understood. This study was conducted to examine the effects of specific oxysterols on the expression of adipogenic transcripts and adipogenic differentiation of C3H10T1/2 mouse stem cells. Cells were treated with 10% Fetal Bovine Serum (control), 500nM Dexamethasone, 0.5mM 3‐Isobutyl‐1‐methlyxanthine, 20µg/ml Insulin (DMI) + 10µM PPARγ agonist Troglitazone (Tro) (DMITro) and DMITro + 10µM 20S hydroxycholesterol (20S), 25 hydroxycholesterol (25), 22R hydroxycholesterol (22R) or 22S hydroxycholesterol (22S) for six days. Gene expression was analysed by real‐time quantitative polymerase chain reaction and expression data analysed using the Statistical Analysis Software (SAS 9.2). Compared to the control, DMITro significantly increased the expression of peroxisome proliferator‐activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), fatty acid binding protein 2 (FABP2) and lipoprotein lipase (LPL). Compared to DMITro, treatment of cells with DMITro + 25 significantly decreased the expression of PPARγ, the master regulator of adipogenesis (P 蠄 0.05). Expression of C/EBPα was significantly decreased by DMITro + 25 and DMITro + 20S (P 蠄 0.05), while the expression of FABP2 was significantly decreased by DMITro + 25, DMITro + 20S and DMITro + 22R (P 蠄 0.05). Lastly, the expression of LPL was significantly decreased by DMITro + 25 and DMITro + 22R (P 蠄 0.05). In conclusion, the results showed that 25 hydroxycholesterol was the most potent in inhibiting the expression of key adipogenic transcripts and adipogenesis of C3H10T1/2 mouse stem cells suggesting its potential application in reducing adipogenesis and obesity.Key words: Oxysterols, C3H10T1/2 stem cells, differentiation, PPARγGrant Funding Source: Supported by Canadian natural science and engineering research council.
The role of p38, ERK1/2 and JNK mitogen activated protein kinase in the anti‐hypertrophic action of AMP‐kinase in cardiomyocytes (1097.13)
Authors: Lopez Pablo , Barreto Giselle , Soto Jessica , Javadov Sabzali 
Published: June 2021

Mitogen activated protein kinases (MAPKs) play an important role in cell grow, proliferation and apoptosis in the heart. The MAPK family involves three major subgroups including extracellular signal‐regulated protein kinase (ERK1/2), p38, and c‐jun N‐terminal kinases (JNK). Despite many studies demonstrating anti‐hypetrophic action of AMP‐kinase (AMPK), a metabolic sensor regulating energy metabolism, the relationship between AMPK activation and MAPKs is not clear yet. We hypothesize that beneficial effects of AMPK are mediated, at least in part, through modification of MAPKs activation. Experiments were performed on H9c2 myoblastic rat cardiomyocytes incubated at 370C with 95% air and 5% CO2. Hypertrophy was induced by treatment of the cells with 200 nM angiotensin II (Ang II, a peptide hormone stimulating hypertrophy) or 10 μM phenylephrine (PE, the α1‐adrenergic receptor agonist). First, we determined time‐course activation (phosphorylation) of ERK1/2, p38 and JNK in response to Ang II and PE. Second, we evaluated, if activation/inhibition of AMPK by metformin/compound C influences activation of the MAPKs induced by AngII or PE. Results demonstrated that maximum activation of all three MAPKs occurs at 10 min after addition of the hypertrophic agents. A time point of 10 min was selected to determine whether AMPK affects MAPKs activation in AngII‐treated cells. Metformin (2 mM) or compound C (10 μM) was added to the culture medium 45 min before AngII or PE treatment. Metformin significantly abrogated the activation of all three MAPKs induced by AngII or PE. Inhibition of AMPK by compound C had no effect on MAPK phosphorylation suggesting that the effects are mediated via AMPK. Surprisingly, losartan had no significant effects on MAPK activation in AngII‐treated cells. In conclusion, our findings demonstrate that ERK1/2, p38 and JNK MAPKs play a crucial role in mediating anti‐hypertrophic effects of AMPK in cardiomyocyte hypertrophy.Grant Funding Source: Supported by the NHLBI NIH grant SC1HL118669 (S.J.) and APS/NHLBI STRIDE Summer Research Fellowship
Dopamine D1‐like receptors differently regulate small G proteins in LRs in human embryonic kidney cells heterologously expressing human D1 or D5 receptors (1097.7)
Authors: Yu Peiying , Yang Yu , Jose Pedro 
Published: June 2021

Small G proteins,e.g.,Rabs (Rab4, Rab5, and Rab11), are involved in G protein‐coupled receptor trafficking, including recycling. We tested the hypothesis that D1‐like receptors (D1R and D5R) differentially regulate the small G proteins Rab4, Rab5, and Rab11 in lipid rafts (LRs) in HEK‐293 cells heterologously expressing either the human D1R or D5R (hD1R or hD5R cells, respectively). In the basal state the Rabs, which co‐fractionated with flotillin‐1, an LR marker protein, were distributed in LR fractions (fractions 2‐6) and nonLR fractions (fractions 7‐12). The D1‐like receptor agonist fenoldopam (1‐5μM/15min), increased Rab4 in LRs in hD1R cells (+38.9±14.8%, vs. control 0.0±4.8 %) and in hD5R cells (+26.9±8.7% vs. control +0.1±3.8 %) (P<0.05, n=4, ANOVA). The effect of fenoldopam on Rab5 was opposite that of Rab4: fenoldopam decreased Rab5 protein in LRs in both cell lines (‐27.4±4.9% hD1R) and (‐19.7±3.0% hD5R) (P<0.05, n=5, ANOVA). Fenoldopam also increased Rab11 protein in LRs in hD1R (+41.6±16.3%) compared to its control (+0.0±0.5%) (P<0.01, n=4, ANOVA) but not in hD5R cells. Moreover, fenoldopam increased Rab11 protein co‐immunoprecipitation with D1R in a time dependent manner which peaked at 1h (22.9±2.5 DU), relative to vehicle‐treatment (9.8±1.9 DU) (P<0.01, n=4, ANOVA). Rab11 protein also co‐immunoprecipitated with D5R but was not affected by fenoldopam. Confocal images corroborated the cell fractionation and co‐immunoprecipitation data: fenoldopam decreased Rab5 in LRs in hD1R and hD5R cells, and increased Rab4 in LRs in hD1R and hD5R cells. Fenoldopam also increased Rab11 protein co‐localization with LR marker protein in LRs in hD1R cells. However, in D5R cells, the D5R and Rab11 co‐localization in LRs was not affected by fenoldopam. We conclude that dopamine D1R and D5R co‐fractionates with Rab4, Rab5, and Rab11 in LRs. These small G proteins may play an important role in D1R and D5R trafficking. Specifically, Rab11 protein may play an important role in D1R recycling.Grant Funding Source: HL023081, HL074940, DK039308