Identification of gene mutation associated with familial dilated cardiomyopathy by whole-exome sequencing / 复旦学报（医学版）

Objective To identify the disease-causing gene in a Chinese pedigree with familial dilated cardiomyopathy (DCM) by whole-exome sequencing.Methods After collecting the clinical data and extracting the whole blood genomic DNA of the 5 family members form a Chinese DCM pedigree,whole-exome sequencing was performed to search the causative genes.Familial co-segregation analysis among the pedigree was subsequently confirmed by traditional Sanger sequencing.Results We performed whole exome sequencing (WES) on representative affected individuals and unaffected familial members from this pedigree.After comparison with variants identified in affected individuals and unaffected individuals,along with previously reported genetic mutations associated with DCM,we found that a heterozygous variant c.961 C＞T (p.Arg321Ter) in exon 6 of the LMNA gene in affected individuals matched the criteria to be the potential disease-causing gene,which was confirmed by Sanger sequencing.This stop-gain mutation leads to only a small part of LMNA-coding protein expressed,therefore we concluded that LMNA c.961 C＞T should be the causative mutation for this familial DCM case.Conclusions The nonsense mutation c.961 C＞ T in gene LMNA identified by whole-exome sequencing might be the pathogenic mutation in this DCM pedigree.

Pathogenesis of coxsackievirus B3-induced myocarditis: role of macrophage migration inhibitory factor / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Macrophage migration inhibitory factor (MIF) is an upstream regulator in immune and inflammatory responses. However, its role in viral myocarditis remains unknown. In this study, we investigated the role of the MIF in coxsackievirus B3 (CVB3)-induced myocarditis.</p><p><b>METHODS</b>Mice were randomized into two groups receiving either Eagle's minimal essential medium (EMEM, control group) or virus solution (infected group). Subsets of mice in the infected group were sacrificed on days 3, 7, 14 and 28 after inoculation. Expression of MIF was detected using an enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction and immunohistochemistry. A neutralizing antibody (Ab) to MIF was injected intraperitoneally from day 0 to 7 after inoculation. Disease severity was estimated by histopathology of the heart and by the heart weight to body weight ratio, and the interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α) in the myocardium were measured by ELISA on day 14.</p><p><b>RESULTS</b>The serum MIF concentration and expression levels of myocardial MIF mRNA and protein were significantly elevated in mice on days 7 and 14 post-infection. The survival rate was markedly higher and disease severity was obviously less in mice treated with anti-MIF Ab. Furthermore, MIF blockade significantly decreased the IL-1β and TNF-α in the myocarditic heart.</p><p><b>CONCLUSION</b>These results demonstrate that MIF is an important naturally occurring inflammatory cytokine in CVB3-induced myocarditis, and anti-MIF Ab may lessen the inflammatory response.</p>

Role of triggering receptor expressed on myeloid cells-1 on coxsackievirus B3-induced inflammation and cardiomyocyte injury / 中华心血管病杂志

<p><b>OBJECTIVE</b>To determine the expression of TREM-1 (triggering receptor expressed on myeloid cells-1) in macrophages after coxsackievirus B3 (CVB3) infection and the cardiomyocytes viability after culturing with supernatant of macrophages in the absence and presence of TREM-1 inhibitor LP-17 to explore if TREM-1 is involved in the pathogenesis of CVB3 infection induced inflammation and cardiomyocytes injury.</p><p><b>METHODS</b>TREM-1 mRNA and TREM-1 and DAP-12 protein expression in macrophages were detected by Real-time PCR at 0, 1, 4, 8 and 12 h and by Western blot at 0, 16, 24 and 48 h post CVB3 infection. TNF-α secretion of macrophages was measure by ELISA, vitality and the apoptosis degree of cardiomyocytes was assessed by CCK8 and Annexin V-FITC after the cardiomyocytes were cultured with the supernatant of macrophages in normal control group, CVB3 infection group and LP-17 pretreated CVB3 infection group.</p><p><b>RESULTS</b>TREM-1 mRNA expression was significantly upregulated at 4, 8, and 12 h (peaked at 8 h) and TREM-1 protein expression was significantly upregulated at 16 and 24 h and returned to baseline level at 48 h after CVB3 infection. The protein expression of DAP-12, a direct downstream signaling molecule of TREM-1, also significantly increased at 24 and 48 h post CVB3 infection (P < 0.01). Level of macrophages secreted TNF-α post CVB3 infection was significantly reduced in LP-17 pretreated cells (P < 0.01), LP-17 pretreatment also significantly improved viability and significantly reduced apoptosis of cardiomyocytes cultured with supernatant of CVB3 infected macrophages (P < 0.01).</p><p><b>CONCLUSION</b>TREM-1 might be an important mediator post CVB3 infection and a major player on inducing excess macrophages-related inflammation and resulting in an indirect injury to cardiomyocytes.</p>

Correlation of cardiac troponin T gene mutations to hypertrophic cardiomyopathy in Chinese patients / 南方医科大学学报

<p><b>OBJECTIVE</b>To study cardiac troponin T (TNNT2) gene mutations in Chinese patients with hypertrophic cardiomyopathy (HCM) and analyze the correlation between the genotype and phenotype.</p><p><b>METHODS</b>Ninety-five unrelated Chinese patients with HCM and 120 control individuals were screened for TNNT2 gene mutations. Seven exons (8, 9, 10, 11, 14, 15, and 16) in the functional regions of TNNT2 gene were amplified using PCR and the products were sequenced. The patients with positive results underwent further family screening.</p><p><b>RESULTS AND CONCLUSION</b>This study did not find any HCM-caused mutations in TNNT2 gene, a result different from the reported rates of TNNT2 gene mutation ranging from 10% to 20% in other nations, suggesting that TNNT2 gene is not a susceptible gene for HCM in Chinese population.</p>

Association between myocardial calpain activation and apoptosis in lipopolysaccharide-induced septic mouse model / 中华心血管病杂志

<p><b>OBJECTIVE</b>in septic mice, myocardial calpain was activated and induced caspase-3 activation, the association between calpain activation and apoptosis was explored in this experiment.</p><p><b>METHODS</b>in in vivo model, adult C57 mice were injected with lipopolysaccharide (LPS, 4 mg/kg, i.p.) to induce sepsis. Myocardial calpain and caspase-3 activities, protein levels of calpain-1, calpain-2, calpastatin, Bcl-2 and Bid were detected by Western blot analysis and myocardial apoptosis was detected by TUNEL, myocardiac function was evaluated by Langendorff system. In in vitro model, adult rat cardiomyocytes were incubated with LPS (1 microg/ml) or co-incubated with calpain inhibitor-III (10 micromol/L), calpain activity, caspase-3 activity, protein levels of Bcl-2 and Bid, and cardiomyocyte apoptosis were detected.</p><p><b>RESULTS</b>in septic mice, myocardial calpain and caspase-3 activity were increased up to 2.7- and 1.8-folds, respectively. Both calpain inhibitor-III and PD150606 significantly attenuated the increase of caspase-3 activity. Myocardial protein levels of calpain-1, calpain-2, calpastatin, Bcl-2 and Bid were similar between control and septic mice, and no cleavage of both Bcl-2 and Bid was found in septic mice. Calpain inhibitor-III significantly improved myocardial function in septic mice. In in vitro model, calpain and caspase-3 activities were increased after 4 h LPS treatment, co-treatment with calpain inhibitor-III prevented caspase-3 activity increase, protein Bcl-2 and Bid were similar between normal cardiomyocytes and LPS-treated cardiomyocytes. Cardiomyocyte apoptosis was similar in in vivo and in vitro septic models.</p><p><b>CONCLUSION</b>myocardial calpain activity is increased in LPS induced septic mice, subsequent caspase-3 activation may contribute to myocardial dysfunction in septic mice without aggravating myocardial apoptosis and Bcl-2 and Bid are not involved on calpain induced caspase-3 activation in our model.</p>

Link between cardiac myosin binding protein-C gene mutation of Pro1208fs and Gly507 Arg and hypertrophic cardiomyopathy in Chinese patients / 中华心血管病杂志

<p><b>OBJECTIVE</b>To detect gene mutations associated with hypertrophic cardiomyopathy (HCM) in Chinese patients and possible correlations between genotype and phenotype.</p><p><b>METHODS</b>Twenty-one unrelated patients with hypertrophic cardiomyopathy were studied. The clinical data including symptoms, physical examination, echocardiography and electrocardiography were collected. The full ecoding exons of cardiac myosin-binding protein C gene (cMYBPC3) were amplified with PCR and the products were sequenced.</p><p><b>RESULTS</b>Two mutations were identified in probands from two families. One mutation was frame shift mutation Pro1208fs in the exon 32 of the cMYBPC3 gene. Pro1208fs mutation was identified in a 59 years old female patient with familial hypertrophic cardiomyopathy. Symptom onset was late and a favorable clinical course was evidenced in this patient. Another mutation was missence mutation Gly507Arg in the exon 17 of the MYBPC3 gene identified in a 24 years old male patient. Diffuse thickness of left ventricular wall, impaired diastolic function and enlarged left atria were evidenced in echocardiography. No mutation was identified in the 80 control healthy individuals.</p><p><b>CONCLUSION</b>cMYBPC3 might be the disease-causing genes in Chinese patients with hypertrophic cardiomyopathy.</p>

Association between expression of chromogranin A and myocardial fibrosis in patients with dilated cardiomyopathy / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the possible correlation between expression of chromogranin A (CGA) and myocardial fibrosis and investigate the potential role of CGA in the development of myocardial fibrosis in patients with dilated cardiomyopathy (DCM).</p><p><b>METHODS</b>Surgical myocardial specimen from 10 DCM patients underwent successful orthotopic cardiac transplantation, and 3 normal myocardial specimen from brain-dead organ donors were obtained. CGA-mRNA, COLI-mRNA, COLIII-mRNA and ADAMTS-1-mRNA were analyzed by real-time PCR. The location and expression of CGA were assessed by immunohistochemistry(INH)with anti-CGA antibody. The collagen specific picrosirius red staining was applied on transversal myocardial slides and the collagen volume fraction (CVF) was calculated. The correlation between CGA and CVF was analyzed.</p><p><b>RESULTS</b>Cytoplasmic expression of CGA assessed by INH showed large amount of strong positive granules densely arranged in the epicardial and endocardial myocardiocytes in DCM specimen while there was only few sparse granules in the normal myocardium (P < 0.05). CVF was significantly higher in DCM myocardial specimen than that in normal specimen (P < 0.001). CGA-mRNA was significantly correlated with COLI-mRNA (r = 0.729), COLIII-mRNA (r = 0.95) and ADAMTS-1-mRNA (r = 0.665, all P < 0.05). Moreover, collagen deposition location was almost identical with the strong positive expression location of CGA.</p><p><b>CONCLUSION</b>We demonstrated for the first time that the deposition of CGA was related with the myocardial fibrosis in DCM heart, therefore, CGA might play an important role by influencing myocardial remodeling and fibrosis in DCM patients.</p>

Assessment of left ventricular systolic synchronicity by real-time three-dimensional echocardiography in patients with dilated cardiomyopathy / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Recent advances in real-time three-dimensional echocardiography (RT3DE) offer the potential to assess the left ventricular (LV) dyssynchrony simultaneously by analyzing the 17 segments time-volume curves. The purpose of this study was to test the feasibility and accuracy of RT3DE for quantitative evaluation of left ventricular systolic synchronicity.</p><p><b>METHODS</b>Twenty-four patients with dilated cardiomyopathy (DCM) and twenty-five healthy volunteers were enrolled in this study. Full volume RT3DE was performed by using Philips IE33 with X3-1 probe. The global and 17-segmental time-volume curves were obtained by the on-line Qlab software (version 4.2). The time to minimal systolic volume in each segment (T(msv)) was taken to derive the following indexes of systolic asynchrony: T(msv) 16-SD, T(msv) 16-Dif, T(msv) 12-SD, T(msv) 12-Dif, T(msv) 6-SD and T(msv) 6-Dif, which meant the standard deviation or the maximal difference of T(msv) among the 16, 12 and 6 segments of the left ventricle respectively. The software also provided with each of the above parameters as a percentage of the cardiac cycle.</p><p><b>RESULTS</b>T(msv) 16-SD, T(msv) 12-SD and T(msv) 6-SD were all significantly larger in the DCM group than those of the control group [T(msv) 16-SD: (52.9 +/- 40.6) ms vs (8.8 +/- 6.2) ms; T(msv) 12-SD: (29.5 +/- 30.8) ms vs (6.9 +/- 4.0) ms; T(msv) 6-SD: (28.9 +/- 34.6) ms vs (7.0 +/- 4.7) ms, all P < or = 0.001]. T(msv) 16-Dif, T(msv) 12-Dif and T(msv) 6-Dif were also significantly larger in the DCM group. There were close negative relations between the LVEF determined by RT3DE and each of the indexes of systolic asynchrony, among which the indexes of T(msv)-16-SD% and T(msv)-16-Dif% correlated most closely (r = -0.703 and r = -0.701, respectively). The DCM patients had significantly larger EDV and ESV, with significantly reduced LVEF compared with the healthy subjects.</p><p><b>CONCLUSION</b>RT3DE provides a simple, useful and unique approach to assess the systolic synchronicity of all the left ventricular segments simultaneously.</p>

Upregulating the expression of angiogenesis-related genes by transplanting autologous mononuclear bone marrow cells into myocardial infarction scar and the periphery / 中华心血管病杂志

<p><b>OBJECTIVE</b>To detect the regulation of angiogenic genes involved in the processes of collateral development.</p><p><b>METHODS</b>Myocardial infarction (MI) scar was induced by cryoinjury in New Zealand rabbits. Four weeks after MI, 24 hours before cell transplantation, bone marrow was aspirated from the right thigh bone and mononuclear bone marrow cells (BMCs) were isolated by Ficoll density gradient centrifugation. Then the mononuclear BMCs (n = 8) or IMDM culture medium (n = 8) were transplanted into infarction scar and the periphery. Four weeks after mononuclear BMCs transplantation, DNA microarray analysis was performed to detect the regulation of angiogenesis-related genes in infarction scar and the periphery. And the differences of angiogenic genes expression were compared among several important growth factors by Western blot.</p><p><b>RESULTS</b>DNA microarray analysis showed the detail regulation of genes involved in the angiogenic processes. There were 15 genes upregulated over 3 times in the infarction scar. In addition, we also found more genes are involved in the process of angiogenesis in its periphery than in the infarction scar (40 genes vs. 15 genes). Western bolt analysis further demonstrated that mononuclear BMCs transplantation was capable of increasing the levels of VEGF, FGF and Angiopoietin-I expression in the infarction scar and its periphery, compared with the control group, P < 0.05.</p><p><b>CONCLUSION</b>These findings indicate that the natural angiogenic processes leading to collateral development are extremely complex, since many kinds of bone marrow-derived growth factors involved in the processes after mononuclear BMCs transplantation into infarction sites.</p>

Microarray analysis of extracellular matrix genes expression in myocardium of mouse with Coxsackie virus B3 myocarditis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Extracellular matrix (ECM) orchestrates cell behaviour including growth, death, apoptosis, adhesion, migration, and invasion by activating several signalling pathways. Certain components of ECM, such as integrins, may act as receptors or co-receptors of enterovirus. ECM-activated gene expressions in myocardium of viral heart disease including myocarditis and partial cardiomyopathy remain elusive. This study was to investigate the expression of ECM-activated genes in myocardium of mouse with viral myocarditis.</p><p><b>METHODS</b>BALB/c mice were infected with Coxsackie virus B3 (CVB3) to establish an animal model of myocarditis. Uninfected mice were also prepared and served as controls. Specific mRNA expression pattern in myocarditic mouse heart was analysed by an in-house cDNA microarray containing 8,192 genes. Overexpressed ECM genes were selected and subsequently confirmed by Northern blot analysis.</p><p><b>RESULTS</b>Nine ECM genes were isolated, from the array of 8,192 genes, as overexpressed genes in hearts of myocarditic mice in comparison with controls. Subsequent Northern blot analysis confirmed that four of the nine genes were highly expressed. Expression of these four genes, Fin15, ILk, Lamr1 and ADAMTS-1, has not been reported previously to be induced by Coxsackie virus.</p><p><b>CONCLUSION</b>CVB3-induced myocarditis is associated with gene expression profiles of certain ECM components.</p>

Expression of Insulin-Like Growth Factor-1 and Its Associated Protein of Mice with Viral Myocarditis / 实用儿科临床杂志

Objective To investigate the changes of insulin-like growth factor-1(IGF-1) and its associated protein in Balb/C mice with viral myocarditis.Methods Sixty Balb/C mice were randomly divided into 2 groups:infected group(n=40) and control group(n=20).Mice in infected group were inoculated intraperitoneally with coxsackievirus B3(CVB3) while control mice with 0.1mL of Eagle′s minimal essential medium(EMEM).Blood and myocardial musculature of all mice were collected on the day of 3,7,15 and 30 after inoculation.The expression of IGF-1 and its associated protein in plasma or myocardium were detected respectively by enzyme-labeled immunosorbent assay(ELISA),immunohistochemistry and reverse transcription polymerase chain reaction(RT-PCR).Results The expression of IGF-1 and its associated protein of mice with viral myocarditis was higher than those in control group and gradual ascent after mice being infected with virus.The expression reached summit on d15,then decreased on d30,but still sustain in a high level.The difference was significant(F=19.53 P