Effects of Positive Airway Pressure on Cardiorespiratory Fitness in Patients with Concomitant Obstructive Sleep Apnea and Cardiovascular Disease.

Background and Objectives: Obstructive sleep apnea (OSA) is common in cardiovascular disease (CVD), although positive airway pressure (PAP) treatment has not been demonstrated to improve the cardiovascular outcome. The objective of this study is to investigate the impact of adherence to PAP therapy on cardiopulmonary exercise testing (CPET) performance in patients with concomitant OSA and CVD. Materials and Methods: This preliminary study involved symptomatic OSA patients requiring PAP treatment who had CVD. All subjects underwent polysomnography, echocardiography, and CPET at baseline. After 6 to 12 months of PAP treatment, CPET performance was re-assessed. The changes in CPET parameters before and after PAP treatment were compared between patients who were adherent to PAP and patients who were not adherent to PAP. Results: A total of 16 OSA patients with an apnea-hypopnea index of 32.0 ± 23.4 were enrolled. Patients were classified into the adherent (n = 9) and non-adherent (n = 7) groups with regard to PAP adherence. After 6 to 12 months of PAP treatment, the PAP-adherent group showed a greater increase in peak VO2 than the PAP-non-adherent group, but the difference between the two groups was not significant (p = 0.581). The decrease in ventilatory equivalent for the carbon dioxide slope (VE/VCO2) was significantly greater in the PAP-adherent group compared to the PAP-non-adherent group (p = 0.030). Conclusions: Adherence to PAP therapy for OSA is associated with an improvement in the VE/VCO2 slope, as an index of the ventilatory response to exercise, in patients with CVD. Screening for sleep apnea in CVD patients may be warranted, and strategies to optimize adherence to PAP in these patients are beneficial. Further evidence is needed to elucidate whether CPET could be routinely used to monitor treatment responses of OSA to PAP therapy in patients with CVD.

High prevalence of ALPK3 premature terminating variants in Korean hypertrophic cardiomyopathy patients.

Background: The alpha-protein kinase 3 (ALPK3) gene (OMIM: 617608) is associated with autosomal recessive familial hypertrophic cardiomyopathy-27 (CMH27, OMIM: 618052). Recently, several studies have shown that monoallelic premature terminating variants (PTVs) in ALPK3 are associated with adult-onset autosomal dominant hypertrophic cardiomyopathy (HCMP). However, these studies were performed on patient cohorts mainly from European Caucasian backgrounds. Methods: To determine if this finding is replicated in the Korean HCMP cohort, we evaluated 2,366 Korean patients with non-syndromic HCMP using exome sequencing and compared the cohort dataset with three independent population databases. Results: We observed that monoallelic PTVs in ALPK3 were also significantly enriched in Korean patients with HCMP with an odds ratio score of 10-21. Conclusions: We suggest that ALPK3 PTV carriers be considered a risk group for developing HCMP and be monitored for cardiomyopathies.

Mmp14-dependent remodeling of the pericellular-dermal collagen interface governs fibroblast survival.

Dermal fibroblasts deposit type I collagen, the dominant extracellular matrix molecule found in skin, during early postnatal development. Coincident with this biosynthetic program, fibroblasts proteolytically remodel pericellular collagen fibrils by mobilizing the membrane-anchored matrix metalloproteinase, Mmp14. Unexpectedly, dermal fibroblasts in Mmp14-/- mice commit to a large-scale apoptotic program that leaves skin tissues replete with dying cells. A requirement for Mmp14 in dermal fibroblast survival is recapitulated in vitro when cells are embedded within, but not cultured atop, three-dimensional hydrogels of crosslinked type I collagen. In the absence of Mmp14-dependent pericellular proteolysis, dermal fibroblasts fail to trigger ß1 integrin activation and instead actuate a TGF-ß1/phospho-JNK stress response that leads to apoptotic cell death in vitro as well as in vivo. Taken together, these studies identify Mmp14 as a requisite cell survival factor that maintains dermal fibroblast viability in postnatal dermal tissues.

The First Korean Case with Cardiac, Facial, and Digital Anomalies with Developmental Delay Caused by De Novo TRAF7 p.Arg655Gln Variant.

TRAF7-related disorders represent some of the rarest inherited disorders, exhibiting clinical features that overlap with cardiac, facial, and digital anomalies with developmental delay (CAFDADD) syndrome, as well as blepharophimosis-mental retardation syndrome (BMRS). A 36-year-old male, presenting with total blindness, blepharophimosis, and intellectual disability, was admitted for the assessment of resting dyspnea several months previously. He had a history of being diagnosed with obstructive sleep apnea (OSA). Transesophageal and transthoracic echocardiography unveiled right ventricular dilatation without significant pulmonary hypertension, bicuspid aortic valve with aortic root aneurysm, and aortic regurgitation in the proband. Sanger sequencing identified a de novo TRAF7 variant (c.1964G>A; p.Arg655Gln). Subsequently, aortic root replacement using the Bentall procedure was performed. However, despite the surgery, he continued to experience dyspnea. Upon re-evaluating OSA with polysomnography, it was discovered that continuous positive airway pressure support alleviated his symptoms. The underlying cause of his symptoms was attributed to OSA, likely exacerbated by the vertebral anomaly and short neck associated with CAFDADD syndrome. Clinicians should be attentive to the symptoms associated with OSA as it is a potentially serious medical condition in patients with TRAF7 variants.

Application of artificial intelligence in hypertension.

Hypertension is an important modifiable risk factor for morbidity and mortality associated with cardiovascular disease. The incidence of hypertension is increasing not only in Korea but also in many Western countries due to the aging of the population and the increase in unhealthy lifestyles. However, hypertension control rates remain low due to poor adherence to antihypertensive medications, low awareness of hypertension, and numerous factors that contribute to hypertension, including diet, environment, lifestyle, obesity, and genetics. Because artificial intelligence (AI) involves data-driven algorithms, AI is an asset to understanding chronic diseases that are influenced by multiple factors, such as hypertension. Although several hypertension studies using AI have been published recently, most are exploratory descriptive studies that are often difficult for clinicians to understand and have little clinical relevance. This review aims to provide a clinician-centered perspective on AI by showing recent studies on the relevance of AI for patients with hypertension. The review is organized into sections on blood pressure measurement and hypertension diagnosis, prognosis, and management.

Comparative Effectiveness of Long-Term Maintenance Beta-Blocker Therapy After Acute Myocardial Infarction in Stable, Optimally Treated Patients Undergoing Percutaneous Coronary Intervention.

Background The benefits of long-term maintenance beta-blocker (BB) therapy in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) have not been well established. Methods and Results Using the Korean nationwide registry, a total of 7159 patients with AMI treated with PCI who received BBs at discharge and were free from death or cardiovascular events for 3 months after PCI were included in the analysis. Patients were divided into 4 groups according to BB maintenance duration: <12 months, 12 to <24 months, 24 to <36 months, and ≥36 months. The primary outcome was the composite of all-cause death, recurrent MI, heart failure, or hospitalization for unstable angina. During a mean 5.0±2.8 years of follow-up, over half of patients with AMI (52.5%) continued BB therapy beyond 3 years following PCI. After propensity score matching and propensity score marginal mean weighting through stratification, a stepwise inverse correlation was noted between BB duration and risk of the primary outcome (<12 months: hazard ratio [HR], 2.19 [95% CI, 1.95-2.46]; 12 to <24 months: HR, 2.10 [95% CI, 1.81-2.43];, and 24 to <36 months: HR, 1.68 [95%CI, 1.45-1.94]; reference: ≥36 months). In a 3-year landmark analysis, BB use for <36 months was associated with an increased risk of the primary outcome (adjusted HR, 1.59 [95% CI, 1.37-1.85]) compared with BB use for ≥36 months. Conclusions Among stabilized patients with AMI following PCI, longer maintenance BB therapy, especially for >36 months, was associated with better clinical outcomes. These findings might imply that a better prognosis can be expected if patients with AMI maintain BB therapy for ≥36 months after PCI. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02806102.

Strategic multimodal non-invasive assessment of cardiac performance in patients with heart failure.

AIMS: Although various non-invasive cardiac examinations are known to be predictive of long-term outcomes in patients with heart failure (HF), combining them properly would provide synergism. We aimed to show that non-invasive cardiac assessments targeting left ventricular filling pressure (LVFP), left atrial remodelling, and exercise capacity would provide better prognostication in combination. METHODS AND RESULTS: This prospective observational study included consecutive hospitalized stage A-C HF patients evaluated with N-terminal pro-B-type natriuretic peptide (NT-proBNP), echocardiography including two-dimensional speckle tracking, and cardiopulmonary exercise testing. According to NT-proBNP and echocardiographic semi-quantitative LVFP grading (Echo-LVFP), patients were classified into three LVFP groups: normal range of both Echo-LVFP and NT-proBNP (Group 1), normal range of Echo-LVFP but elevated NT-proBNP (Group 2), and elevated Echo-LVFP and NT-proBNP (Group 3). The adverse outcome was defined as a composite of cardiovascular death, non-fatal acute coronary syndrome, acute stroke, or HF-related hospitalization. Among 224 HF patients (mean age of 63.8 ± 11.6 years, 158 men) analysed, 160 (71.4%) had ischaemic aetiology. During the follow-up of 18.6 ± 9.8 months, event-free survival in Group 2 (n = 56, age of 65.4 ± 12.4) was better than that in Group 3 (n = 45, age of 68.5 ± 11.5) but worse than that in Group 1 (n = 123, mean age of 61.4 ± 10.5) (log-rank P < 0.001). Mechanical left atrial dysfunction (peak longitudinal strain <28%) (adjusted hazard ratio 5.69, 95% confidence interval 1.06-4.48) and limited exercise capacity (peak VO2 per +5 mL/kg/min) (adjusted hazard ratio 0.63, 95% confidence interval 0.46-0.87) were also predictable adverse outcomes. Serial addition of peak VO2 and left atrial strain to the model incrementally enhanced the predictive power of LVFP-based risk stratification for adverse outcomes. CONCLUSIONS: The combination of NT-proBNP and Echo-LVFP could be used to predict adverse outcomes in patients with HF of various stages. Left atrial mechanics and exercise capacity are incremental to prognostication. Non-invasive test findings could be strategically combined to provide an integrative profile of cardiac performance.

The prognostic value of cardiopulmonary exercise testing and HFA-PEFF in patients with unexplained dyspnea and preserved left ventricular ejection fraction.

BACKGROUND: HFA-PEFF and cardiopulmonary exercise testing (CPET) are comprehensive diagnostic tools for heart failure with preserved ejection fraction (HFpEF). We aimed to investigate the incremental prognostic value of CPET for the HFA-PEFF score among patients with unexplained dyspnea with preserved ejection fraction (EF). METHODS: Consecutive patients with dyspnea and preserved EF (n = 292) were enrolled between August 2019 and July 2021. All patients underwent CPET and comprehensive echocardiography, including two-dimensional speckle tracking echocardiography in the left ventricle, left atrium and right ventricle. The primary outcome was defined as a composite cardiovascular event including cardiovascular-related mortality, acute recurrent heart failure hospitalization, urgent repeat revascularization/myocardial infarction or any hospitalization due to cardiovascular events. RESULTS: The mean age was 58 ± 14.5 years, and 166 (56.8%) participants were male. The study population was divided into three groups based on the HFA-PEFF score: < 2 (n = 81), 2-4 (n = 159), and ≥ 5 (n = 52). HFA-PEFF score ≥ 5, VE/VCO2 slope, peak systolic strain rate of the left atrium and resting diastolic blood pressure were independently associated with composite cardiovascular events. Furthermore, the addition of VE/VCO2 and HFA-PEFF to the base model showed incremental prognostic value for predicting composite cardiovascular events (C-statistic 0.898; integrated discrimination improvement 0.129, p = 0.032; net reclassification improvement 1.043, p ≤ 0.001). CONCLUSIONS: CPET could be exploited for the HFA-PEFF approach in terms of incremental prognostic value and diagnosis among patients with unexplained dyspnea with preserved EF.

Proteolytic regulation of a galectin-3/Lrp1 axis controls osteoclast-mediated bone resorption.

Bone-resorbing osteoclasts mobilize proteolytic enzymes belonging to the matrix metalloproteinase (MMP) family to directly degrade type I collagen, the dominant extracellular matrix component of skeletal tissues. While searching for additional MMP substrates critical to bone resorption, Mmp9/Mmp14 double-knockout (DKO) osteoclasts-as well as MMP-inhibited human osteoclasts-unexpectedly display major changes in transcriptional programs in tandem with compromised RhoA activation, sealing zone formation and bone resorption. Further study revealed that osteoclast function is dependent on the ability of Mmp9 and Mmp14 to cooperatively proteolyze the ß-galactoside-binding lectin, galectin-3, on the cell surface. Mass spectrometry identified the galectin-3 receptor as low-density lipoprotein-related protein-1 (Lrp1), whose targeting in DKO osteoclasts fully rescues RhoA activation, sealing zone formation and bone resorption. Together, these findings identify a previously unrecognized galectin-3/Lrp1 axis whose proteolytic regulation controls both the transcriptional programs and the intracellular signaling cascades critical to mouse as well as human osteoclast function.

A Zeb1/MtCK1 metabolic axis controls osteoclast activation and skeletal remodeling.

Osteoclasts are bone-resorbing polykaryons responsible for skeletal remodeling during health and disease. Coincident with their differentiation from myeloid precursors, osteoclasts undergo extensive transcriptional and metabolic reprogramming in order to acquire the cellular machinery necessary to demineralize bone and digest its interwoven extracellular matrix. While attempting to identify new regulatory molecules critical to bone resorption, we discovered that murine and human osteoclast differentiation is accompanied by the expression of Zeb1, a zinc-finger transcriptional repressor whose role in normal development is most frequently linked to the control of epithelial-mesenchymal programs. However, following targeting, we find that Zeb1 serves as an unexpected regulator of osteoclast energy metabolism. In vivo, Zeb1-null osteoclasts assume a hyperactivated state, markedly decreasing bone density due to excessive resorptive activity. Mechanistically, Zeb1 acts in a rheostat-like fashion to modulate murine and human osteoclast activity by transcriptionally repressing an ATP-buffering enzyme, mitochondrial creatine kinase 1 (MtCK1), thereby controlling the phosphocreatine energy shuttle and mitochondrial respiration. Together, these studies identify a novel Zeb1/MtCK1 axis that exerts metabolic control over bone resorption in vitro and in vivo.

Matrix remodeling controls a nuclear lamin A/C-emerin network that directs Wnt-regulated stem cell fate.

Skeletal stem cells (SSCs) reside within a three-dimensional extracellular matrix (ECM) compartment and differentiate into multiple cell lineages, thereby controlling tissue maintenance and regeneration. Within this environment, SSCs can proteolytically remodel the surrounding ECM in response to growth factors that direct lineage commitment via undefined mechanisms. Here, we report that Mmp14-dependent ECM remodeling coordinates canonical Wnt signaling and guides stem cell fate by triggering an integrin-activated reorganization of the SCC cytoskeleton that controls nuclear lamin A/C levels via the linker of nucleoskeleton and cytoskeleton (LINC) complexes. In turn, SSC lamin A/C levels dictate the localization of emerin, an inner nuclear membrane protein whose ability to regulate ß-catenin activity modulates Wnt signaling while directing lineage commitment in vitro and in vivo. These findings define a previously undescribed axis wherein SSCs use Mmp14-dependent ECM remodeling to control cytoskeletal and nucleoskeletal organization, thereby governing Wnt-dependent stem cell fate decisions.

Relationship of Serial High-Sensitivity C-Reactive Protein Changes to Long-term Clinical Outcomes in Stabilised Patients After Myocardial Infarction.

BACKGROUND: Little is known about the association between serial high-sensitivity C-reactive protein (hsCRP) measurements and long-term outcomes in post-myocardial infarction (MI) patients. We aimed to investigate the usefulness of serial hsCRP measurements for risk stratification in stabilised post-MI patients after percutaneous coronary intervention (PCI). METHODS: A total of 1018 patients who had hsCRP values at both baseline and 1 year after MI were included. High inflammatory status was defined as hsCRP > 2 mg/L. Patients were classified into 4 groups: persistently low, falling (first high then low hsCRP), rising (first low then high hsCRP), and persistently high hsCRP. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE: a composite of all-cause of death, MI, and cerebrovascular accident) within 4 years after the second hsCRP measurement. RESULTS: At 1 year after MI, the numbers of patients in the persistently low, falling, rising, and persistently high hsCRP groups were 394 (38.7%), 358 (35.2%), 69 (6.8%), and 197 (19.4%), respectively. The incidence of MACCE was progressively elevated from the persistently low to the falling, rising, and persistently high hsCRP groups (4.8%, 8.1%, 10.1%, and 13.2%, respectively; P = 0.004). Persistently high hsCRP was an independent predictor of MACCE (adjusted hazard ratio 2.55; 95% confidence interval 1.35-4.81; P = 0.004) and provided incremental prognostic value beyond that of the baseline clinical risk model (net reclassification improvement = 0.397; integrated discrimination improvement = 0.025; all P < 0.001). CONCLUSIONS: Among stabilised post-MI patients who underwent PCI, persistently high hsCRP was frequently seen 1 year after MI and was strongly associated with long-term adverse clinical outcomes. Serial measurements of hsCRP during clinical follow-up after MI may help to identify patients at higher risk for mortality and morbidity.

Impact of a screening protocol for blood pressure level for hypertension in the Korean community health survey.

PURPOSE: A community program is an efficient model for improving the management of chronic diseases such as hypertension, diabetes, and dyslipidemia. A specific blood pressure (BP) measurement protocol was developed for community settings in which BP was measured by the interviewer at the interviewee's home. MATERIALS AND METHODS: In the 2018 Korean Community Health Survey, BP was measured twice at a five-minute interval after a five-minute resting period at the beginning of the survey. In 2019, BP was measured at the end of the survey after a two-minute rest and was obtained as three measurements at one-minute intervals. As factors related to BP level, stressful stimuli within 30 min before BP measurement such as smoking, caffeine, and/or exercise; duration of rest; and survey year were analysed. RESULTS: The mean age of participants was 55.2 years, and females accounted for 55.4% of the participants (n = 399,838). Stressful stimuli were observed in 21.9% of the participants in 2018 (n = 188,440) and 11.3% in 2019 (n = 211,398). Duration of rest was 0 min (2.1%), two minutes (55.0%), and five minutes (47.9%). When adjusted for age, sex, body mass index, antihypertensive medication, the arm of measurement, survey year (beta= -4.092), stressful stimuli (beta = 0.834), and resting time (beta = -1.296 per one minute of rest) were significant factors for mean systolic BP. A two-minute rest was not a significant factor in mean BP. The differences in adjusted mean systolic BPs were significant for rest times of five minutes vs. two minutes (3.1 mmHg, p < 0.0001), for stressful stimuli (0.8 mmHg, p < 0.0001), and for survey year (127.8 ± 0.2 mmHg vs. 122.2 ± 0.3 mmHg for 2018 vs. 2019, p < 0.0001). CONCLUSION: For the community-based home visit survey, avoidance of stressful stimuli, five-minute rest, and allocation of BP measurement in the last part of the survey was useful for obtaining a stable BP level.

3D Printed Personalized External Aortic Root Model in Marfan Syndrome with Isolated Sinus of Valsalva Aneurysm Caused by a Novel Pathogenic FBN1 p.Gly1127Cys Variant.

The major cause of death in Marfan syndrome (MFS) is cardiovascular complications, particularly progressive dilatation of the proximal aorta, rendering these patients at risk of aortic dissection or fatal rupture. We report a 3D printed personalized external aortic root model for MFS with an isolated sinus of Valsalva aneurysm caused by a novel pathogenic FBN1 variant. A 67-year-old female with a history of lens dislocation and retinal detachment in the left eye was admitted for the evaluation of resting dyspnea several months prior. Transesophageal and transthoracic echocardiography revealed severe aortic valve regurgitation and a large left coronary sinus of Valsalva aneurysm in the proband. Sanger sequencing identified a heterozygous p.Gly1127Cys variant in the FBN1 gene; previously, a mutation at this amino acid position was described as pathogenic (p.Gly1127Ser; rs137854468). A 3D printed personalized external aortic root model based on a multidetector computed tomography scan was constructed to illustrate the location of the ostium of the left main coronary artery on the aneurysm of the left coronary artery cusp. Aortic root replacement with the Bentall procedure matched the exact shape of the 3D printed model. Creation of a 3D printed patient-specific model could be useful in facilitating the development of next-generation medical devices and resolving the risks of postoperative complications and aortic root disease.

Epidemiology of Venous Thromboembolism and Treatment Pattern of Oral Anticoagulation in Korea, 2009-2016: a Nationwide Study Based on the National Health Insurance Service Database.

BACKGROUND: The annual incidence of venous thromboembolism (VTE) is increasing, and the treatment pattern of oral anticoagulants (OACs) has changed with introduction of new oral anticoagulants (NOACs). The aims of this study were to assess the annual incidence of VTE in a Korean population and the change of treatment pattern with availability of NOACs using a population-based database. METHODS: Using the Korean National Health Insurance Services database, we identified patients diagnosed with VTE between 2009 and 2016. The annual prevalence of VTE and clinical characteristics and treatment pattern were investigated. The annual incidence of VTE was calculated using direct and indirect methods using the estimated Korean population in 2009 as the reference. RESULTS: The annual incidence of VTE in Korean has increased yearly from 23.9 per 100,000 in 2009 to 42.2 in 2016. The overall rate of OAC prescription for VTE treatment increased from 55.9% to 68% in the same time period. The rate of initiation of NOAC treatment greatly increased, particularly from 2013 onwards, with a 20-fold increase from 2009 to 2016 (2.1% vs. 54.3%). CONCLUSIONS: The annual incidence of VTE in Korea increased by almost two-fold from 2009 to 2016. The rate of initiation of NOAC treatment has increased substantially since 2013, and these agents have surpassed VKAs as the anticoagulant of choice for VTE. This temporal pattern of OAC prescription is consistent with the current clinical guidelines, which indicate NOACs over the warfarin in patients with VTE.

Case Report: Novel Likely Pathogenic ACTN2 Variant Causing Heterogeneous Phenotype in a Korean Family With Left Ventricular Non-compaction.

Left ventricular non-compaction (LVNC) is a very rare primary cardiomyopathy with a genetic etiology, resulting from the failure of myocardial development during embryogenesis, and it carries a high risk of left ventricular dysfunction, thromboembolic phenomenon, and malignant arrhythmias. Here, we report the first case of familial LVNC in Korea, caused by a novel ACTN2 missense variant. We performed duo exome sequencing (ES) to examine the genome of the proband and his father. A 15-year-old boy was admitted for the evaluation of exertional dyspnea for 2 weeks. He was diagnosed with LVNC with a dilated cardiomyopathy phenotype [left ventricular end-diastolic dimension 60 mm, interventricular septal dimension 8.2 mm by transthoracic echocardiography (TTE)]. For the screening of familial cardiomyopathy, TTE and cardiac magnetic resonance imaging (cMRI) were performed, which revealed hypertrophic and isolated LVNC in the proband's father and sister, respectively. In particular, the cMRI revealed dense hypertrabeculation with focal aneurysmal changes in the apical septal wall in the proband's father. ES of the father-son duo identified a novel heterozygous c.668T>C variant of the ACTN2 gene (NM_001103.3:c.668T>C, p.Leu223Pro; no rsID) as the candidate cause of autosomal dominant LVNC. Sanger sequencing confirmed this novel variant in the proband, his father, and sister, but not in the proband's grandmother. Even within families harboring the same variant, a variable risk of adverse outcomes is common. Therefore, familial screening for patients with LVNC associated with ACTN2 variant should be performed for early detection of the LVNC phenotype associated with poor outcomes, such as dilated LVNC.

Phenotypic Diversity of Cardiomyopathy Caused by an MYBPC3 Frameshift Mutation in a Korean Family: A Case Report.

Restrictive cardiomyopathy (RCM) is one of the rarest cardiac disorders, with a very poor prognosis, and heart transplantation is the only long-term treatment of choice. We reported that a Korean family presented different cardiomyopathies, such as idiopathic RCM and hypertrophic cardiomyopathy (HCM), caused by the same MYBPC3 mutation in different individuals. A 74-year-old male was admitted for the evaluation of exertional dyspnea, palpitations, and pitting edema in both legs for several months. Transthoracic echocardiography (TTE) showed RCM with biatrial enlargement and pericardial effusion. Cardiac magnetic resonance (CMR) images revealed normal left ventricular chamber size, borderline diffuse left ventricular hypertrophy and very large atria. In contrast to the proband, CMR images showed asymmetric septal hypertrophy of the left ventricle, consistent with a diagnosis of HCM in the proband's two daughters. Of the five heterozygous variants identified as candidate causes of inherited cardiomyopathy by whole exome sequencing in the proband, Sanger sequencing confirmed the presence of a heterozygous frameshift mutation (NM_000256.3:c.3313_3314insGG; p.Ala1105Glyfs*85) in MYBPC3 in the proband and his affected daughters, but not in his unaffected granddaughter. There is clinical and genetic overlap of HCM with restrictive physiology and RCM, especially when HCM is combined with severe myocardial fibrosis. Family screening with genetic testing and CMR imaging could be excellent tools for the evaluation of idiopathic RCM.

High Mobility Group Box Chromosomal Protein-1 Induces Myofibroblast Differentiation and Extracellular Matrix Production via RAGE, p38, JNK and AP-1 Signaling Pathways in Nasal Fibroblasts.

BACKGROUND: Chronic rhinosinusitis is involved in myofibroblast differentiation and extracellular matrix (ECM) accumulation. High mobility group box chromosomal protein 1 (HMGB-1) is known to stimulate lung fibroblast to produce ECM in lung fibrosis. The aim of this study was to investigate whether HMGB-1 induces myofibroblast differentiation and ECM production in nasal fibroblasts and to identify the signal pathway. METHODS: Human nasal fibroblasts were cultured. After stimulation with HMGB-1, expressions of α-smooth muscle actin (α-SMA) and fibronectin were determined by real-time PCR and western blot. Total collagen was measured by Sircol assay. To investigate signal pathway, various signal inhibitors and RAGE siRNA were used. RESULTS: HMGB-1 increased α-SMA and fibronectin in mRNA and protein levels. It also increased collagen production. RAGE siRNA inhibited HMGB-1-induced α-SMA and fibronectin, and production of collagen. Furthermore, the inhibitors of RAGE downstream molecules such as p38, JNK and AP-1 also blocked the HMGB-1-induced effects. CONCLUSIONS: HMGB-1 induces myofibroblast differentiation and ECM production in nasal fibroblast, which is mediated by RAGE, p38, JNK and AP-1 signal pathway. These results suggest that HMGB-1 may play an important role in tissue remodeling during chronic rhinosinusitis progression.

The relationship between miRNA-26b and connective tissue growth factor in rat models of aortic banding and debanding.

BACKGROUND/AIMS: Connective tissue growth factor (CTGF) is a profibrotic factor implicated in pressure overload-mediated myocardial fibrosis. In this study, we determined the role of predicted CTGF-targeting microRNAs (miRNAs) in rat models of aortic stenosis and reverse cardiac remodeling. METHODS: Minimally invasive ascending aortic banding was performed in 24 7-week-old male Sprague-Dawley rats, which were divided into three groups. The banding group consisted of eight rats that were sacrificed immediately after 6 weeks of aortic constriction. The debanding group underwent aortic constriction for 4 weeks and was sacrificed 2 weeks after band removal. The third group underwent sham surgery. We investigated the expression of CTGF, transforming growth factor-ß1 (TGFß1), and matrix metalloproteinase-2 using ELISA and examined miRNA-26b, miRNA-133a, and miRNA-19b as predicted CTGF-targeting miRNAs based on miRNA databases in 24-hour TGFß-stimulated and TGFß- washed fibroblasts and myocardial tissues from all subjects. RESULTS: CTGF was elevated in 24-hour TGFß-stimulated fibroblasts and decreased in 24-hour TGFß-washed fibroblasts. miRNA-26b was significantly increased in TGFß-washed fibroblasts compared with control and TGFß-stimulated fibroblasts (p < 0.05). CTGF expression was significantly higher in the banding group than that in the sham and debanding groups. The relative expression levels of miRNA-26b were higher in the debanding group than in the banding group. CONCLUSION: The results of our study using models of aortic banding and debanding suggested that miRNA-26b was significantly increased after aortic debanding. The in vitro model yielded the same results: miRNA-26b was upregulated after removal of TGFß from fibroblasts.