The role of noncoding genetic variants in cardiomyopathy

Cardiomyopathies remain one of the leading causes of morbidity and mortality worldwide. Environmental risk factors and genetic predisposition account for most cardiomyopathy cases. As with all complex diseases, there are significant challenges in the interpretation of the molecular mechanisms underlying cardiomyopathy-associated genetic variants. Given the technical improvements and reduced costs of DNA sequence technologies, an increasing number of patients are now undergoing genetic testing, resulting in a continuously expanding list of novel mutations. However, many patients carry noncoding genetic variants, and although emerging evidence supports their contribution to cardiac disease, their role in cardiomyopathies remains largely understudied. In this review, we summarize published studies reporting on the association of different types of noncoding variants with various types of cardiomyopathies. We focus on variants within transcriptional enhancers, promoters, intronic sites, and untranslated regions that are likely associated with cardiac disease. Given the broad nature of this topic, we provide an overview of studies that are relatively recent and have sufficient evidence to support a significant degree of causality. We believe that more research with additional validation of noncoding genetic variants will provide further mechanistic insights on the development of cardiac disease, and noncoding variants will be increasingly incorporated in future genetic screening tests

Vascular smooth muscle cell-derived nerve growth factor regulates sympathetic collateral branching to innervate blood vessels in embryonic skin

Blood vessels serve as intermediate conduits for the extension of sympathetic axons towards target tissues, while also acting as crucial targets for their homeostatic processes encompassing the regulation of temperature, blood pressure, and oxygen availability. How sympathetic axons innervate not only blood vessels but also a wide array of target tissues is not clear. Here we show that in embryonic skin, after the establishment of co-branching between sensory nerves and blood vessels, sympathetic axons invade the skin alongside these sensory nerves and extend their branches towards these blood vessels covered by vascular smooth muscle cells (VSMCs). Our mosaic labeling technique for sympathetic axons shows that collateral branching predominantly mediates the innervation of VSMC-covered blood vessels by sympathetic axons. The expression of nerve growth factor (NGF), previously known to induce collateral axon branching in culture, can be detected in the vascular smooth muscle cell (VSMC)-covered blood vessels, as well as sensory nerves. Indeed, VSMC-specific Ngf knockout leads to a significant decrease of collateral branching of sympathetic axons innervating VSMC-covered blood vessels. These data suggest that VSMC-derived NGF serves as an inductive signal for collateral branching of sympathetic axons innervating blood vessels in the embryonic skin

Identification of Antifungal Compounds Active against Candida albicans Using an Improved High-Throughput Caenorhabditis elegans Assay

Candida albicans, the most common human pathogenic fungus, can establish a persistent lethal infection in the intestine of the microscopic nematode Caenorhabditis elegans. The C. elegans–C. albicans infection model was previously adapted to screen for antifungal compounds. Modifications to this screen have been made to facilitate a high-throughput assay including co-inoculation of nematodes with C. albicans and instrumentation allowing precise dispensing of worms into assay wells, eliminating two labor-intensive steps. This high-throughput method was utilized to screen a library of 3,228 compounds represented by 1,948 bioactive compounds and 1,280 small molecules derived via diversity-oriented synthesis. Nineteen compounds were identified that conferred an increase in C. elegans survival, including most known antifungal compounds within the chemical library. In addition to seven clinically used antifungal compounds, twelve compounds were identified which are not primarily used as antifungal agents, including three immunosuppressive drugs. This assay also allowed the assessment of the relative minimal inhibitory concentration, the effective concentration in vivo, and the toxicity of the compound in a single assay

Υποθέσεις κρίσεων του Ορθόδοξου Κλήρου στην Ενετοκρατούμενη Κρήτη

Με γνώμονα έγγραφο, με χρονολογία 29 Οκτωβρίου 1604, από τον κώδικα με αριθμό 20 της Καθολικής Αρχιεπισκοπής Κρήτης, που βρίσκεται σήμερα στο αρχείο της Καθολικής Αρχιεπισκοπής Τήνου, δια του οποίου επιβάλλεται ποινή στον ορθόδοξο κληρικό Απόστολο Γιαλινά της ενορίας Αγίας Ειρήνης του χωρίου Κατσαμπά περιοχής Χάνδακα, επειδή τέλεσε γάμο χωρίς την κατάλληλη εκκλησιαστική άδεια και ενάντια στον κανόνα της Συνόδου του Τριδέντου, επιχειρούμε να μελετήσουμε την λειτουργία της Ενετικής Εκκλησιαστικής Διοικήσεως στην Κρήτη, τις σχέσεις της με την Ορθόδοξη Εκκλησία αλλά και τον τρόπο με τον οποίο αντιμετώπιζε και έκρινε υποθέσεις που αφορούσαν την δεύτερη.Based on a document dated 29 October 1604, from Canon Law code no. 20 of the Catholic Archdiocese of Crete, which is available nowadays in the archives of the Catholic Archdiocese of Tinos, for which a penalty is imposed on the Orthodox cleric Apostolos Gialinas of the parish of Saint Irene in the village of Katsamba, Heraklion region, because he took a wedding without the appropriate church permission and against the decrees of the Council of Trent. We attempt to study the functioning of the Venetian Ecclesiastical Administration in Crete, its relations with the Orthodox Church and the manner in which it handled and reached decisions concerning the latter

Interaction of Candida albicans with an Intestinal Pathogen, Salmonella enterica Serovar Typhimurium▿

Candida albicans is an opportunistic human fungal pathogen that normally resides in the gastrointestinal tract and on the skin as a commensal but can cause life-threatening invasive disease. Salmonella enterica serovar Typhimurium is a gram-negative bacterial pathogen that causes a significant amount of gastrointestinal infection in humans. Both of these organisms are also pathogenic to the nematode Caenorhabditis elegans, causing a persistent gut infection leading to worm death. In the present study, we used a previously developed C. elegans polymicrobial infection model to assess the interactions between S. Typhimurium and C. albicans. We observed that when C. elegans is infected with C. albicans and serovar Typhimurium, C. albicans filamentation is inhibited. The inhibition of C. albicans filamentation by S. Typhimurium in C. elegans appeared to be mediated by a secretary molecule, since filter-sterilized bacterial supernatant was able to inhibit C. albicans filamentation. In vitro coculture assays under planktonic conditions showed that S. Typhimurium reduces the viability of C. albicans, with greater effects seen at 37°C than at 30°C. Interestingly, S. Typhimurium reduces the viability of both yeast and filamentous forms of C. albicans, but the killing appeared more rapid for the filamentous cells. The antagonistic interaction was also observed in a C. albicans biofilm environment. This study describes the interaction between two diverse human pathogens that reside within the gastrointestinal tract and shows that the prokaryote, S. Typhimurium, reduces the viability of the eukaryote, C. albicans. Identifying the molecular mechanisms of this interaction may provide important insights into microbial pathogenesis

Candida albicans Hyphal Formation and Virulence Assessed Using a Caenorhabditis elegans Infection Model ▿

Candida albicans colonizes the human gastrointestinal tract and can cause life-threatening systemic infection in susceptible hosts. We study here C. albicans virulence determinants using the nematode Caenorhabditis elegans in a pathogenesis system that models candidiasis. The yeast form of C. albicans is ingested into the C. elegans digestive tract. In liquid media, the yeast cells then undergo morphological change to form hyphae, which results in aggressive tissue destruction and death of the nematode. Several lines of evidence demonstrate that hyphal formation is critical for C. albicans pathogenesis in C. elegans. First, two yeast species unable to form hyphae (Debaryomyces hansenii and Candida lusitaniae) were less virulent than C. albicans in the C. elegans assay. Second, three C. albicans mutant strains compromised in their ability to form hyphae (efg1Δ/efg1Δ, flo8Δ/flo8Δ, and cph1Δ/cph1Δ efg1Δ/efg1Δ) were dramatically attenuated for virulence. Third, the conditional tet-NRG1 strain, which enables the external manipulation of morphogenesis in vivo, was more virulent toward C. elegans when the assay was conducted under conditions that permit hyphal growth. Finally, we demonstrate the utility of the C. elegans assay in a screen for C. albicans virulence determinants, which identified several genes important for both hyphal formation in vivo and the killing of C. elegans, including the recently described CAS5 and ADA2 genes. These studies in a C. elegans-C. albicans infection model provide insights into the virulence mechanisms of an important human pathogen

Sympathetic NPY controls glucose homeostasis, cold tolerance, and cardiovascular functions in mice

Summary: Neuropeptide Y (NPY) is best known for its effects in the brain as an orexigenic and anxiolytic agent and in reducing energy expenditure. NPY is also co-expressed with norepinephrine (NE) in sympathetic neurons. Although NPY is generally considered to modulate noradrenergic responses, its specific roles in autonomic physiology remain under-appreciated. Here, we show that sympathetic-derived NPY is essential for metabolic and cardiovascular regulation in mice. NPY and NE are co-expressed in 90% of prevertebral sympathetic neurons and only 43% of paravertebral neurons. NPY-expressing neurons primarily innervate blood vessels in peripheral organs. Sympathetic-specific NPY deletion elicits pronounced metabolic and cardiovascular defects in mice, including reductions in insulin secretion, glucose tolerance, cold tolerance, and pupil size and elevated heart rate, while notably, however, basal blood pressure was unchanged. These findings provide insight into target tissue-specific functions of NPY derived from sympathetic neurons and imply its potential involvement in metabolic and cardiovascular diseases

The Diastolic Pulmonary Gradient Does Not Predict Survival in Patients With Pulmonary Hypertension Due to Left Heart Disease

ObjectivesThis study sought to evaluate if diastolic pulmonary gradient (DPG) can predict survival in patients with pulmonary hypertension due to left heart disease (PH-LHD).BackgroundPatients with combined post- and pre-capillary PH-LHD have worse prognosis than those with passive pulmonary hypertension. The transpulmonary gradient (TPG) and pulmonary vascular resistance (PVR) have commonly been used to identify high-risk patients. However, these parameters have significant shortcomings and do not always correlate with pulmonary vasculature remodeling. Recently, it has been suggested that DPG may be better a marker, yet its prognostic ability in patients with cardiomyopathy has not been fully assessed.MethodsA retrospective cohort of 1,236 patients evaluated for unexplained cardiomyopathy at Johns Hopkins Hospital was studied. All patients underwent right heart catheterization and were followed until death, cardiac transplantation, or the end of the study period (mean time 4.4 years). The relationships between DPG, TPG, or PVR and survival in subjects with PH-LHD (n = 469) were evaluated with Cox proportional hazards regression and Kaplan-Meier analyses.ResultsDPG was not significantly associated with mortality (hazard ratio [HR]: 1.02, p = 0.10) in PH-LHD whereas elevated TPG and PVR predicted death (HR: 1.02, p = 0.046; and HR: 1.11, p = 0.002, respectively). Similarly, DPG did not differentiate survivors from non-survivors at any selected cut points including a DPG of 7 mm Hg.ConclusionsIn this retrospective study of patients with cardiomyopathy and PH-LHD, an elevated DPG was not associated with worse survival

Heart Rate Dependence of the Pulmonary Resistance x Compliance (RC) Time and Impact on Right Ventricular Load

<div><p>Background</p><p>The effect of heart rate (HR) and body surface area (BSA) on pulmonary RC time and right ventricular (RV) load is unknown.</p><p>Methods</p><p>To determine the association of HR and BSA with the pulmonary RC time and measures of RV load, we studied three large patient cohorts including subjects with 1) known or suspected pulmonary arterial hypertension (PAH) (n = 1008), 2) pulmonary hypertension due to left heart disease (n = 468), and 3) end-stage heart failure with reduced ejection fraction (n = 150). To corroborate these associations on an individual patient level, we performed an additional analysis using high-fidelity catheters in 22 patients with PAH undergoing right atrial pacing.</p><p>Results</p><p>A faster HR inversely correlated with RC time (p<0.01 for all), suggesting augmented RV pulsatile loading. Lower BSA directly correlated with RC time (p<0.05) although the magnitude of this effect was smaller than for HR. With incremental atrial pacing, cardiac output increased and total pulmonary resistance (TPR) fell. However, effective arterial elastance, its mean resistive component (TPR/heart period; 0.60±0.27 vs. 0.79±0.45;p = 0.048), and its pulsatile component (0.27±0.18 vs 0.39±0.28;p = 0.03) all increased at faster HR.</p><p>Conclusion</p><p>Heart rate and BSA are associated with pulmonary RC time. As heart rate increases, the pulsatile and total load on the RV also increase. This relationship supports a hemodynamic mechanism for adverse effects of tachycardia on the RV.</p></div