Depression, anxiety, and quality of life as predictors of rehospitalization in patients with chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) is a severe condition, often co-occurring with depression and anxiety, that strongly affects the quality of life (QoL) in some patients. Conversely, depressive and anxiety symptoms are associated with a 2-3 fold increase in mortality risk and were shown to act independently of typical risk factors in CHF progression. The aim of this study was to examine the impact of depression, anxiety, and QoL on the occurrence of rehospitalization within one year after discharge in CHF patients. METHODS: 148 CHF patients were enrolled in a 10-center, prospective, observational study. All patients completed two questionnaires, the Hospital Anxiety and Depression Scale (HADS) and the Questionnaire Short Form Health Survey 36 (SF-36) at discharge timepoint. RESULTS: It was found that demographic and clinical characteristics are not associated with rehospitalization. Still, the levels of depression correlated with gender (p ≤ 0.027) and marital status (p ≤ 0.001), while the anxiety values ​​were dependent on the occurrence of chronic obstructive pulmonary disease (COPD). However, levels of depression (HADS-Depression) and anxiety (HADS-Anxiety) did not correlate with the risk of rehospitalization. Univariate logistic regression analysis results showed that rehospitalized patients had significantly lower levels of Bodily pain (BP, p = 0.014), Vitality (VT, p = 0.005), Social Functioning (SF, p = 0.007), and General Health (GH, p = 0.002). In the multivariate model, poor GH (OR 0.966, p = 0.005) remained a significant risk factor for rehospitalization, and poor General Health is singled out as the most reliable prognostic parameter for rehospitalization (AUC = 0.665, P = 0.002). CONCLUSION: Taken together, our results suggest that QoL assessment complements clinical prognostic markers to identify CHF patients at high risk for adverse events. CLINICAL TRIAL REGISTRATION: The study is registered under http://clinicaltrials.gov (NCT01501981, first posted on 30/12/2011), sponsored by Charité - Universitätsmedizin Berlin.

First-in-Human Study of the Safety, Pharmacokinetics, and Pharmacodynamics of MHV370, a Dual Inhibitor of Toll-Like Receptors 7 and 8, in Healthy Adults.

BACKGROUND AND OBJECTIVE: MHV370, a dual antagonist of human Toll-like receptors (TLR) 7 and 8, suppresses cytokines and interferon-stimulated genes in vitro and in vivo, and  has demonstrated efficacy in murine models of lupus. This first-in-human study aimed to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of single and multiple doses of MHV370 in healthy adults, as well as the effects of food consumption on a single dose of MHV370. METHODS: This was a phase 1, randomised, placebo-controlled study conducted in three parts. In part A, participants received (3:1) a single ascending dose (SAD) of 1, 3, 10, 20, 40, 80, 160, 320, 640 and 1000 mg MHV370 or placebo. In part B, participants received (3:1) multiple ascending doses (MAD) of 25, 50, 100, 200 and 400 mg MHV370 twice daily (b.i.d) or placebo for 14 days. In part C, participants received an open-label single dose of 200 mg MHV370 under fasted or fed conditions. Safety, pharmacokinetic and pharmacodynamic parameters were evaluated. RESULTS: MHV370 was well tolerated, and no safety signal was observed in the study. No dose-limiting adverse events occurred across the dose range evaluated. Plasma concentrations of MHV370 increased with dose (mean [SD] maximum plasma concentrations ranged from 0.97 [0.48] to 1670 [861.0] ng/mL for SAD of 3-1000 mg, 29.5 [7.98] to 759 [325.0] ng/mL for MAD of 25-400 mg b.i.d. on day 1). The intake of food did not have a relevant impact on the pharmacokinetics of MHV370. Pharmacodynamic data indicated time- and dose-dependent inhibition of TLR7-mediated CD69 expression on B cells (100% inhibition at 24 h post-dose starting from SAD 160 mg and MAD 50 mg b.i.d.) and TLR8-mediated TNF release after ex vivo stimulation (>90% inhibition at 24 h post-dose starting from SAD 320 mg and MAD 100 mg b.i.d.). CONCLUSION: The safety, pharmacokinetic and pharmacodynamic data support the further development of MHV370 in systemic autoimmune diseases driven by the overactivation of TLR7 and TLR8.

Metabolic, Intestinal, and Cardiovascular Effects of Sotagliflozin Compared With Empagliflozin in Patients With Type 2 Diabetes: A Randomized, Double-Blind Study.

OBJECTIVE: Inhibiting sodium-glucose cotransporters (SGLTs) improves glycemic and cardiovascular outcomes in patients with type 2 diabetes (T2D). We investigated the differential impact of selective SGLT2 inhibition and dual inhibition of SGLT1 and SGLT2 on multiple parameters. RESEARCH DESIGN AND METHODS: Using a double-blind, parallel-group design, we randomized 40 patients with T2D and hypertension to receive the dual SGLT1 and SGLT2 inhibitor sotagliflozin 400 mg or the selective SGLT2 inhibitor empagliflozin 25 mg, with preexisting antihypertensive treatment, for 8 weeks. In an in-house testing site, mixed-meal tolerance tests (MMTTs) and other laboratory and clinical evaluations were used to study metabolic, intestinal, cardiovascular, and urinary parameters over 24 h. RESULTS: Changes from baseline in glycemic and blood pressure control; intestinal, urine, and metabolic parameters; and cardiovascular biomarkers were generally similar with sotagliflozin and empagliflozin. During the breakfast MMTT, sotagliflozin significantly reduced incremental area under the curve (AUC) values for postprandial glucose, insulin, and glucose-dependent insulinotropic polypeptide (GIP) and significantly increased incremental AUCs for postprandial glucagon-like peptide 1 (GLP-1) relative to empagliflozin, consistent with sotagliflozin-mediated inhibition of intestinal SGLT1. These changes waned during lunch and dinner MMTTs. Both treatments significantly lowered GIP incremental AUCs relative to baseline over the 14 h MMTT interval; the most vigorous effect was seen with sotagliflozin soon after start of the first meal of the day. No serious or severe adverse events were observed. CONCLUSIONS: Changes from baseline in glycemic and blood pressure control, cardiovascular biomarkers, and other parameters were comparable between sotagliflozin and empagliflozin. However, sotagliflozin but not empagliflozin inhibited intestinal SGLT1 after breakfast as shown by larger changes in postprandial glucose, insulin, GIP, and GLP-1 AUCs, particularly after breakfast. Additional study is warranted to assess the clinical relevance of transient SGLT1 inhibition and differences in incretin responses (NCT03462069).

Safety and Biological Activity of Rozibafusp alfa, a Bispecific Inhibitor of Inducible Costimulator Ligand and B Cell Activating Factor, in Patients With Rheumatoid Arthritis: Results of a Phase 1b, Randomized, Double-Blind, Placebo-Controlled, Multiple Ascending Dose Study.

OBJECTIVE: To assess the safety and biological activity of rozibafusp alfa, a first-in-class bispecific antibody-peptide conjugate targeting inducible costimulator ligand (ICOSL) and B cell activating factor (BAFF), in patients with rheumatoid arthritis (RA). METHODS: This phase 1b, double-blind, placebo-controlled, multiple ascending dose study included 34 patients (18-75 years; 82.4% female) with active RA (Disease Activity Score of 28 joints-C-reactive protein [DAS28-CRP] >2.6, on stable methotrexate) randomized 3:1 to receive rozibafusp alfa (n = 26, in four ascending dose cohorts of 70, 140, 210, and 420 mg) or a placebo (n = 8) subcutaneously once every 2 weeks for 10 weeks (six total doses), with 24 weeks of follow-up. The primary end point was the incidence of treatment-emergent adverse events (TEAEs). Additional assessments included serum pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity, and RA disease activity measures (DAS28-CRP, Patient Global Assessment of Disease, and Physician Global Assessment of Disease). RESULTS: TEAEs occurred in 96.2% and 87.5% of patients receiving rozibafusp alfa and the placebo, respectively; most were mild or moderate in severity. Two (7.7%) patients treated with rozibafusp alfa reported serious TEAEs; none were considered treatment related. Multiple doses of rozibafusp alfa showed nonlinear PK (mean t1/2  = 4.6-9.5 days) and dose-related, reversible PD (>90% ICOSL receptor occupancy in 210- and 420-mg cohorts; reduction in naïve B cells and increase in memory B cells in all cohorts). Five (20%) patients developed anti-rozibafusp alfa antibodies, with no apparent impact on safety. RA disease activity showed greater numerical improvement from baseline with rozibafusp alfa versus the placebo in the 210- and 420-mg cohorts. CONCLUSION: Multiple ascending doses of rozibafusp alfa were well tolerated, with PK and PD reflecting dual ICOSL and BAFF blockade. Findings support further clinical evaluation of rozibafusp alfa in autoimmune disease.

Efficacy, Safety, and Mechanistic Insights of Cotadutide, a Dual Receptor Glucagon-Like Peptide-1 and Glucagon Agonist.

CONTEXT: Cotadutide is a dual receptor agonist with balanced glucagon-like peptide-1 and glucagon activity. OBJECTIVE: To evaluate different doses of cotadutide and investigate underlying mechanisms for its glucose-lowering effects. DESIGN/SETTING: Randomized, double-blind, phase 2a study conducted in 2 cohorts at 5 clinical trial sites. PATIENTS: Participants were 65 adult overweight/obese patients with type 2 diabetes mellitus; 63 completed the study; 2 were withdrawn due to AEs. INTERVENTION: Once-daily subcutaneous cotadutide or placebo for 49 days. Doses (50-300 µg) were uptitrated weekly (cohort 1) or biweekly (cohort 2). MAIN OUTCOME MEASURES: Co-primary end points (cohort 1) were percentage changes from baseline to end of treatment in glucose (area under the curve from 0 to 4 hours [AUC0-4h]) post-mixed-meal tolerance test (MMTT) and weight. Exploratory measures included postprandial insulin and gastric emptying time (GET; cohort 2). RESULTS: Patients received cotadutide (cohort 1, n = 26; cohort 2, n = 20) or placebo (cohort 1, n = 13; cohort 2, n = 6). Significant reductions were observed with cotadutide vs placebo in glucose AUC0-4h post MMTT (least squares mean [90% CI], -21.52% [-25.68, -17.37] vs 6.32% [0.45, 12.20]; P < 0.001) and body weight (-3.41% [-4.37, -2.44] vs -0.08% [-1.45, 1.28]; P = 0.002). A significant increase in insulin AUC0-4h post MMTT was observed with cotadutide (19.3 mU.h/L [5.9, 32.6]; P = 0.008) and GET was prolonged on day 43 with cotadutide vs placebo (t½: 117.2 minutes vs -42.9 minutes; P = 0.0392). CONCLUSION: These results suggest that the glucose-lowering effects of cotadutide are mediated by enhanced insulin secretion and delayed gastric emptying. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03244800.

Assessment of the anti-CD40 antibody iscalimab in patients with primary Sjögren's syndrome: a multicentre, randomised, double-blind, placebo-controlled, proof-of-concept study.

BACKGROUND: Primary Sjögren's syndrome is an autoimmune disease that presents as dryness of the mouth and eyes due to impairment of the exocrine glands. To our knowledge, no systemic therapies for primary Sjögren's syndrome have shown efficacy. CD40-CD154-mediated T cell-B cell interactions in primary Sjögren's syndrome contribute to aberrant lymphocyte activation in inflamed tissue, leading to sialadenitis and other tissue injury. Therefore, we investigated the safety and preliminary efficacy of iscalimab (CFZ533), a novel anti-CD40 monoclonal antibody, in patients with primary Sjögren's syndrome. METHODS: This multicentre, randomised, double-blind, placebo-controlled, proof-of-concept study took place at ten investigational sites across Europe (UK, n=4; Germany, Switzerland, and Hungary, n=1 each) and the USA (n=3). Eligible patients were aged 18-75 years and fulfilled the 2002 American European consensus group diagnostic classification criteria for primary Sjögren's syndrome. In the double-blind phase of the trial, patients were randomly assigned (2:1) via computer-generated unique randomisation numbers to receive subcutaneous iscalimab (3 mg/kg) or placebo at weeks 0, 2, 4, and 8 (cohort 1) or intravenous iscalimab (10 mg/kg) or placebo at weeks 0, 2, 4, and 8 (cohort 2). Randomisation was stratified according to baseline intake of oral corticosteroids. At week 12, patients in both cohorts received open-label iscalimab (same dose and route) for 12 weeks. The primary objectives of the study were to assess the safety, tolerability, and efficacy of multiple doses of iscalimab in the two sequential dose cohorts. Safety and tolerability were assessed by adverse events and efficacy of iscalimab versus placebo was assessed by clinical disease activity, as measured by the change in European League Against Rheumatism Sjögren's syndrome disease activity index (ESSDAI) score after 12 weeks of treatment. Analyses were done on a per-protocol basis. The trial was registered with ClinicalTrials.gov, NCT02291029. FINDINGS: Between Oct 22, 2014, and June 28, 2016, we assessed 82 patients for eligibility (25 for cohort 1 and 57 for cohort 2). 38 patients were excluded because of ineligibility. In cohort 1, 12 patients were randomly assigned to receive either 3 mg/kg doses of iscalimab (n=8) or placebo (n=4), and in cohort 2, 32 patients were randomly assigned to receive either intravenous 10 mg/kg doses of iscalimab (n=21) or placebo (n=11). Adverse events were similar between iscalimab treatment groups and placebo groups, with adverse events occurring in all patients in cohort 1, and in 52% and 64% of the iscalimab and placebo groups, respectively, in cohort 2. Two serious adverse events were reported (one case of bacterial conjunctivitis in cohort 1 and one case of atrial fibrillation in cohort 2), which were unrelated to treatment with iscalimab. Intravenous treatment with iscalimab resulted in a mean reduction of 5·21 points (95% CI 0·96-9·46; one-sided p=0·0090) in ESSDAI score compared with placebo. There was no signficiant difference in ESSDAI score between subcutaneous iscalimab and placebo. INTERPRETATION: To our knowledge, this is the first randomised, placebo-controlled proof-of-concept study of a new investigational drug for primary Sjögren's syndrome that indicates preliminary efficacy. Our data suggest a role of CD40-CD154 interactions in primary Sjögren's syndrome pathology and the therapeutic potential for CD40 blockade in this disease should be investigated further. FUNDING: Novartis Pharma.

Targeting CD20+ B-lymphocytes in inflammatory dilated cardiomyopathy with rituximab improves clinical course: a case series.

BACKGROUND: The aetiology of dilated cardiomyopathy (DCM) is highly heterogeneous including genetic and/or acquired (infective, toxic, immune, endocrine, and nutritional) factors. The major part of acquired DCM in developed countries is caused by either viral or autoimmune myocarditis. It is believed that the activation of the T-lymphocyte cell system is the major pathomechanism underlying autoimmune myocarditis and inflammatory DCM (DCMi). However, in the hearts of a subset of patients, a significant number of CD20+ B-lymphocytes can be detected too. Limited information exists on the role of B-cell-dependent mechanisms in the progression of DCMi. Particularly CD20+ B-lymphocytes, which can be targeted by anti-CD20+ B-lymphocytes antibodies or inhibitors, might contribute to the pathogenesis of myocardial damage beyond antibody production. CASE SUMMARY: Here, we present a case series of six patients with subacute and chronic endomyocardial biopsy-proven CD20+ B-lymphocyte-associated DCMi, where symptomatic heart failure therapy, with or without combined immunosuppressive therapy with steroid-based treatment regime, was insufficient to improve cardiac function. Five patients improved clinically several weeks after a standard infusion protocol with rituximab, a chimeric monoclonal antibody against the pan-B-cell surface molecule CD20. DISCUSSION: Our case series shows that CD20+ B-lymphocyte persistence can play a pathophysiologic role in a subset of DCMi patients and highlights the potential of targeting CD20+ B cells in patients with prominent CD20+ B-lymphocyte persistence.

A novel dual glucagon-like peptide and glucagon receptor agonist SAR425899: Results of randomized, placebo-controlled first-in-human and first-in-patient trials.

AIMS: To evaluate the safety, pharmacokinetics and pharmacodynamics of SAR425899, a novel polypeptide, active as an agonist at both the glucagon-like peptide-1 receptor (GLP-1R) and the glucagon receptor (GCR), in healthy volunteers and in overweight/obese patients with type 2 diabetes (T2D). METHODS: Subcutaneous administrations of SAR425899 were tested in two randomized, placebo-controlled, double-blind clinical trials. In the first trial, healthy overweight volunteers (body mass index [BMI] 25-30 kg/m2 ; n = 32) received single-ascending doses (0.01-0.1 mg) of SAR425899 or placebo. In the second, a multiple-ascending-dose trial (NCT02411825), healthy normal- to overweight volunteers (BMI 20-30 kg/m2 ; n = 40) and overweight/obese patients with T2D (BMI 28-42 kg/m2 ; n = 36) received daily doses of SAR425899 or placebo over 21 or 28 days, respectively. RESULTS: The most frequently reported adverse events were gastrointestinal; gastrointestinal side effects were less pronounced in patients with T2D compared with healthy volunteers. SAR425899 significantly reduced levels of fasting plasma glucose (P < 0.05 vs. placebo) and glycated haemoglobin (P < 0.001 versus placebo) in patients with T2D. Additionally, SAR425899 led to reductions in body weight, with a maximal reduction of 5.32 kg in healthy volunteers and 5.46 kg in patients with T2D (P < 0.001 vs. placebo) at end of treatment. CONCLUSIONS: SAR425899 was well tolerated and led to favourable glycaemic effects in patients with T2D and weight reduction in both healthy volunteers and patients. Whether dual GLP-1R/GCR agonism represents a treatment method that is superior to pure GLP-1R agonists for obesity and diabetes treatment remains to be confirmed.

MEDI0382, a GLP-1 and glucagon receptor dual agonist, in obese or overweight patients with type 2 diabetes: a randomised, controlled, double-blind, ascending dose and phase 2a study.

BACKGROUND: Weight loss is often key in the management of obese or overweight patients with type 2 diabetes, yet few treatments for diabetes achieve clinically meaningful weight loss. We aimed to assess the efficacy, tolerability, and safety of treatment with MEDI0382, a balanced glucagon-like peptide-1 and glucagon receptor dual agonist developed to provide glycaemic control and weight loss, in patients with type 2 diabetes. METHODS: This randomised, placebo-controlled, double-blind, combined multiple-ascending dose (MAD) and phase 2a study was done at 11 study sites (hospitals and contract research organisations) in Germany. We enrolled patients aged 18-65 years with controlled type 2 diabetes (glycated haemoglobin A1c [HbA1c] levels of 6·5-8·5% at screening) and a body-mass index between 27 kg/m2 and 40 kg/m2. An interactive web-response system was used to randomly assign patients to receive MEDI0382 or placebo. Patients were randomly assigned 2:1 in cohorts A-C and 3:1 in cohorts D and E in the MAD portion of the study, and 1:1 in the phase 2a portion. Randomisation was done by a contracted third-party operator who was not involved in the clinical operations of the study. The pharmacists, participants, and study site personnel involved in treating and assessing participants were masked to treatment allocation. Patients received once-daily subcutaneous injections of the study drug at doses of no more than 300 µg for 22 days or less in the MAD portion of the study, and a dose of no more than 200 µg for 41 days or less in the phase 2a portion. The two primary endpoints of the phase 2a portion were the change from baseline to day 41 in glucose area under the curve at 0-4 h (AUC0-4 h) after a mixed-meal tolerance test (MMTT), assessed in all participants who received at least one dose of study drug and whose measurements were taken at baseline and day 41, and change from baseline in bodyweight, assessed in the intention-to-treat (ITT) population. Safety analyses were done in all participants who received any study drug analysed according to the treatment they received. This study is registered with ClinicalTrials.gov, number NCT02548585. FINDINGS: Patients were recruited between Dec 9, 2015, and Feb 24, 2017. 61 patients were randomly assigned to the MAD part of the study (42 to MEDI0382 and 19 to placebo). 51 patients were randomly assigned to the phase 2a part, of whom 25 were randomly assigned to MEDI0382 and 26 to placebo. In the phase 2a study, three patients in the MEDI0382 group and one in the placebo group discontinued, all as a result of adverse events. 22 (88%) patients in the MEDI0382 group and 25 (96%) in the placebo group received at least one dose and had measurements taken at baseline and day 41. Glucose AUC0-4 h post MMTT decreased significantly with MEDI0382 versus placebo (least squares [LS] mean -32·78% [90% CI -36·98 to -28·57] vs -10·16% [-14·10 to -6·21], and the mean difference was -22·62% [-28·40 to -16·85]; p<0·0001). In the ITT population, reduction in bodyweight was significantly greater with MEDI0382 than with placebo (LS mean -3·84 kg [90% CI -4·55 to -3·12] vs -1·70 kg [-2·40 to -1·01] and mean difference of 2·14 kg [-3·13 to -1·31]; p=0·0008). The proportion of patients who had a treatment-emergent adverse event (TEAE) was similar between treatment groups (22 [88%] of 25 in the MEDI0382 group vs 23 [88%] of 26 in the placebo group); gastrointestinal disorders (18 [72%] vs 13 [40%]) and decreased appetite (five [20%] vs none) occurred more frequently with MEDI0382 than placebo. No participants in the MEDI0382 group had a grade 3 or worse TEAE (vs two [8%] in the placebo group). INTERPRETATION: MEDI0382 has the potential to deliver clinically meaningful reductions in blood glucose and bodyweight in obese or overweight individuals with type 2 diabetes. FUNDING: MedImmune.

CCN1 mutation is associated with atrial septal defect.

The genetic basis of congenital heart disease remains unknown in most of the cases. Recently, a novel mouse model shed new light on the role of CCN1/CYR61, a matricellular regulatory factor, in cardiac morphogenesis. In a candidate gene approach, we analyzed a cohort of 143 patients with atrial septal defects (ASD) by sequencing the coding exons of CCN1. In addition to three frequent polymorphisms, we identified an extremely rare novel heterozygous missense mutation (c.139C > T; p.R47W) in one patient with severe ASD. The mutation leads to an exchange of residues with quite different properties in a highly conserved position of the N-terminal insulin-like growth factor binding protein module. Further bioinformatic analysis, exclusion of known ASD disease genes as well as the exclusion of the mutation in a very high number of ethnically matched controls (more than 1,000 individuals) and in public genetic databases, indicates that the p.R47W variant is a probable disease-associated mutation. The report about ASD in mice in heterozygous Ccn 1 +/- animals strongly supports this notion. Our study is the first to suggest a relationship between a probable CCN1 mutation and ASD. Our purpose here was to draw attention to CCN1, a gene that we believe may be important for genetic analysis in patients with congenital heart disease.

A promoter polymorphism -945C>G in the connective tissue growth factor in heart failure patients with mechanical circulatory support: a new marker for bridge to recovery?

OBJECTIVES: Mechanical circulatory support (MCS) creates improvement of cardiac function in a small portion of patients with idiopathic dilated cardiomyopathy (iDCM). Among other factors, cardiomyocyte hypertrophy seems to represent an important prerequisite for MCS-related cardiac recovery. We have previously shown that connective tissue growth factor (CTGF) leads to adaptive cardiomyocyte hypertrophy associated with a protective cardiac function in transgenic mice. To test whether a functional genetic variant in the CTGF promoter impacts MCS-related cardiac recovery, three groups of iDCM patients with and without cardiac recovery on MCS were genotyped. METHODS: The CTGF promoter variant (c.-945C>G) was analysed in 314 patients with iDCM receiving medical treatment only (Group I). Forty-nine iDCM patients who were either weaned from MCS for more than 6 months (Group II; n=20) or bridged to cardiac transplantation (Group III: n=29) were also genotyped. Patients on MCS were followed up for at least 12 months. Clinical characteristics and outcome on MCS were correlated with the respective genotypes. RESULTS: The c.-945C>G allele frequencies in 314 iDCM patients (Group I) were similar to controls deposited in the HapMap database or those published in a recent study. There were no differences in allele prevalence between patients with mild to moderate iDCM (Group I) compared with patients with severe iDCM requiring MCS (Groups II and III). Intriguingly, 50% of patients who were weaned from MCS (Group II) were homozygous for the G allele compared with only 17.2% of patients included in Group III, which is a significant difference (P=0.03). CONCLUSIONS: Homozygosity of the promoter-activating G allele in the CTGF_c.-945C>G variant is overrepresented in patients with cardiac recovery on MCS when compared with iDCM patients without cardiac recovery. Further studies are needed to evaluate c.-945C>G as a genetic predictor for clinical outcome on MCS.

Novel mutations in the sarcomeric protein myopalladin in patients with dilated cardiomyopathy.

Recently, missense mutations in titin-associated proteins have been linked to the pathogenesis of dilated cardiomyopathy (DCM). The objective of this study was to search for novel disease-associated mutations in the two human titin-binding proteins myopalladin and its amino-terminal-interacting partner cardiac ankyrin-repeat protein (CARP). In a cohort of 255 cases with familial and sporadic DCM, we analyzed the coding regions and all corresponding intron flanks located in the MYPN and CARP-encoding ANKRD1 gene. Two heterozygous missense mutations were detected in the MYPN gene (p.R955W and p.P961L), but neither of these mutations was found in 300 healthy controls. Both mutations were located in the α-actinin-binding region of myopalladin. Endomyocardial biopsies from the p.R955W carrier showed normal subcellular localization of myopalladin and α-actinin in cardiac myocytes, while their regular sarcomeric staining pattern was significantly disrupted in the p.P961L carrier, indicating that disturbed myofibrillogenesis and altered sarcomere assembly are the cause of the disease. In the ANKRD1 gene, we identified synonymous base exchanges (c.108T>C and c.-79C>T, respectively), but no non-synonymous mutations. In summary, we have identified novel missense mutations in the third immunoglobulin-like domain of myopalladin, which have either no or profound effects on the molecular composition of the sarcomere. According to our epidemiological data, the prevalence of ANKRD1 mutations seems to be lower than that of its binding partner myopalladin, indicating the clinical significance of myopalladin for the functional integrity of the sarcomeric apparatus and the protection against DCM.

Cardiac alpha-myosin (MYH6) is the predominant sarcomeric disease gene for familial atrial septal defects.

Secundum-type atrial septal defects (ASDII) account for approximately 10% of all congenital heart defects (CHD) and are associated with a familial risk. Mutations in transcription factors represent a genetic source for ASDII. Yet, little is known about the role of mutations in sarcomeric genes in ASDII etiology. To assess the role of sarcomeric genes in patients with inherited ASDII, we analyzed 13 sarcomeric genes (MYH7, MYBPC3, TNNT2, TCAP, TNNI3, MYH6, TPM1, MYL2, CSRP3, ACTC1, MYL3, TNNC1, and TTN kinase region) in 31 patients with familial ASDII using array-based resequencing. Genotyping of family relatives and control subjects as well as structural and homology analyses were used to evaluate the pathogenic impact of novel non-synonymous gene variants. Three novel missense mutations were found in the MYH6 gene encoding alpha-myosin heavy chain (R17H, C539R, and K543R). These mutations co-segregated with CHD in the families and were absent in 370 control alleles. Interestingly, all three MYH6 mutations are located in a highly conserved region of the alpha-myosin motor domain, which is involved in myosin-actin interaction. In addition, the cardiomyopathy related MYH6-A1004S and the MYBPC3-A833T mutations were also found in one and two unrelated subjects with ASDII, respectively. No mutations were found in the 11 other sarcomeric genes analyzed. The study indicates that sarcomeric gene mutations may represent a so far underestimated genetic source for familial recurrence of ASDII. In particular, perturbations in the MYH6 head domain seem to play a major role in the genetic origin of familial ASDII.

Investigation of association between PFO complicated by cryptogenic stroke and a common variant of the cardiac transcription factor GATA4.

Patent foramen ovale (PFO) is associated with clinical conditions including cryptogenic stroke, migraine and varicose veins. Data from studies in humans and mouse suggest that PFO and the secundum form of atrial septal defect (ASDII) exist in an anatomical continuum of septal dysmorphogenesis with a common genetic basis. Mutations in multiple members of the evolutionarily conserved cardiac transcription factor network, including GATA4, cause or predispose to ASDII and PFO. Here, we assessed whether the most prevalent variant of the GATA4 gene, S377G, was significantly associated with PFO or ASD. Our analysis of world indigenous populations showed that GATA4 S377G was largely Caucasian-specific, and so subjects were restricted to those of Caucasian descent. To select for patients with larger PFO, we limited our analysis to those with cryptogenic stroke in which PFO was a subsequent finding. In an initial study of Australian subjects, we observed a weak association between GATA4 S377G and PFO/Stroke relative to Caucasian controls in whom ASD and PFO had been excluded (OR = 2.16; p = 0.02). However, in a follow up study of German Caucasians no association was found with either PFO or ASD. Analysis of combined Australian and German data confirmed the lack of a significant association. Thus, the common GATA4 variant S377G is likely to be relatively benign in terms of its participation in CHD and PFO/Stroke.

Mutations in the cardiac transcription factor GATA4 in patients with lone atrial fibrillation.

Familial recurrence of atrial fibrillation (AF) is reported in up to 15% of patients with lone AF. Recently, it was proposed that congenital defects in the morphogenesis of the pulmonary vein myocardium are involved in genetic pathogenesis of lone AF. GATA4 is a cardiac transcription factor essentially involved in myocardial development. Mutations in GATA4 are associated with congenital cardiac malformations. To investigate whether GATA4 mutations represent a genetic origin for AF the coding region of GATA4 was sequenced in 96 patients with lone AF. We found a GATA4 mutation (M247T) in a patient with familial lone AF and atrial septal aneurysm without interatrial shunts. The mutation affects a deeply conserved domain adjacent to the first zinc finger domain of GATA4 and was not reported before. A second GATA4 mutation (A411V) was found in a female patient with sporadic lone AF. This variant was previously reported in patients with cardiac septal defects. However, no anomalies of the atrial or ventricular septa were noted in the AF patient harboring A411V. We report for the first time that mutations in the cardiac transcription factor GATA4 may represent a genetic origin of lone AF. The study proposes that lone AF may share a common genetic origin with congenital cardiac malformations.

Evidence for CTLA4 as a susceptibility gene for dilated cardiomyopathy.

The cytotoxic T-lymphocyte antigen 4 (CTLA4) is an inhibitory receptor expressed on activated T cells with downregulatory properties. The aim of this study was to analyse whether single-nucleotide polymorphisms (SNPs) within the CTLA4 gene are associated with the diagnosis and disease course of dilated cardiomyopathy (DCM). In two independent cohorts of DCM patients (n=251 and 223) and healthy controls (n=591), the promoter and all four exons of the CTLA4 gene, including their flanking regions, were genotyped, and the resulting allele and genotype distributions of the identified SNPs were compared between the groups. We confirmed two known SNPs in the promoter region (-318C>T) and in exon 1 (+49A>G;Thr17Ala). The allelic frequencies and genotypic distribution of the promoter SNP were similar for DCM patients compared with controls. However, the G/G genotype of the Thr17Ala variant was significantly more frequent in DCM patients compared with controls (37 out of 251 patients (14.7%) versus 44 out of 591 controls (7.4%), P=0.005). The higher frequency of the G/G genotype was confirmed in an additional DCM cohort (29 out of 223 patients (13.0%), P=0.039), indicating that this SNP functions as a risk factor for DCM. At follow-up after 1 year, the ejection fraction and the end-diastolic diameter of the left ventricle did not differ significantly between DCM patients carrying the G/G genotype versus other genotypes (n=199). Our data indicate that the common CTLA4 variant, Thr17Ala, confers susceptibility for DCM, but does not seem to influence the course of the disease 1 year after diagnosis.

A gain-of-function TBX20 mutation causes congenital atrial septal defects, patent foramen ovale and cardiac valve defects.

BACKGROUND: Ostium secundum atrial septal defects (ASDII) account for approximately 10% of all congenital heart defects (CHD), and mutations in cardiac transcription factors, including TBX20, were identified as an underlying cause for ASDII. However, very little is known about disease penetrance in families and functional consequences of inherited TBX20 mutations. METHODS: The coding region of TBX20 was directly sequenced in 170 ASDII patients. Functional consequences of one novel mutation were investigated by surface plasmon resonance, CD spectropolarymetry, fluorescence spectrophotometry, luciferase assay and chromatin immunoprecipitation. RESULTS: We found a novel mutation in a highly conserved residue in the T-box DNA binding domain (I121M) segregating with CHD in a three generation kindred. Four mutation carriers revealed cardiac phenotypes in terms of cribriform ASDII, large patent foramen ovale or cardiac valve defects. Interestingly, tertiary hydrophobic interactions within the mutant TBX20 T-box were significantly altered leading to a more dynamic structure of the protein. Moreover, Tbx20-I121M resulted in a significantly enhanced transcriptional activity, which was further increased in the presence of co-transcription factors GATA4/5 and NKX2-5. Occupancy of DNA binding sites on target genes was also increased. CONCLUSIONS: We suggest that TBX20-I121M adopts a more fluid tertiary structure leading to enhanced interactions with cofactors and more stable transcriptional complexes on target DNA sequences. Our data, combined with that of others, suggest that human ASDII may be related to loss-of-function as well as gain-of-function TBX20 mutations.

Plasma HER2 levels are not associated with cardiac function or hypertrophy in control subjects and heart failure patients.

A proper interaction between the endocardial-derived ligand Neuregulin-1 and the myocardial "Human Epidermal growth factor Receptor 2" (HER2) is essential for maintaining heart function. The shed extracellular domain (ECD) of HER2 circulates in blood and serves as a surrogate marker for breast cancer. Altered cardiac loading conditions are accompanied by dysregulation of the myocardial HER2 gene expression. We studied 193 controls with preserved ejection fraction (EF>55%) and 572 patients with different degrees of systolic heart failure: 98 had EF 45-55%, 138 patients EF 35-44%, and 336 patients, EF <35%, respectively. The corresponding mean HER2 levels were 6.44 ± 0.46 ng/mL, 6.07 ± 0.76 ng/mL and 6.57 ± 0.87 ng/mL, and 6.17 ± 0.71 ng/mL, respectively. Furthermore, there was no significant association between plasma HER2 levels and left ventricular filling pressures or the left ventricular wall thickness. The HER2 plasma levels do not reflect the cardiac function and are therefore not useful as a biomarker for heart failure.

Molecular genetics of congenital atrial septal defects.

Congenital heart defects (CHD) are the most common developmental errors in humans, affecting 8 out of 1,000 newborns. Clinical diagnosis and treatment of CHD has dramatically improved in the last decades. Hence, the majority of CHD patients are now reaching reproductive age. While the risk of familial recurrence has been evaluated in various population studies, little is known about the genetic pathogenesis of CHD. In recent years significant progress has been made in uncovering genetic processes during cardiac development. Data from human genetic studies in CHD patients indicate that the genetic aetiology was presumably underestimated in the past. Inherited mutations in genes encoding cardiac transcription factors and sarcomeric proteins were found as an underlying cause for familial recurrence of non-syndromic CHD in humans, in particular cardiac septal defects. Notably, the cardiac phenotypes most frequently seen in mutation carriers are ostium secundum atrial septal defects (ASDII). This review outlines experimental approaches employed for the detection of CHD-related genes in humans and summarizes recent findings in molecular genetics of congenital cardiac septal defects with an emphasis on ASDII.