Meta-analysis of the association between ACE I/D polymorphism and IVST/MWT in HCM patients.

<p>HCM, hypertrophic cardiomyopathy; IVST, interventricular septum thickness; MWT, maximal left ventricle wall thickness. The SMD represents the standard mean difference of IVST/MWT (mm) between DI/II and DD genotype in HCM patients.</p

Flow diagram of studies selection.

<p>IVST, interventricular septum thickness; SNP, Single Nucleotide Polymorphism. HCM, hypertrophic cardiomyopathy; ACE, angiotensin converting enzyme; AGT, angiotensinogen. Fig. 1a, ACE I/D flow diagram; Fig. 1b, AGT flow diagram.</p

The Influence of Angiotensin Converting Enzyme and Angiotensinogen Gene Polymorphisms on Hypertrophic Cardiomyopathy

<div><p>Some studies have reported that angiotensin converting enzyme (ACE) and angiotensinogen (AGT) genes have been associated with hypertrophic cardiomyopathy (HCM). However, there have been inconsonant results among different studies. To clarify the influence of ACE and AGT on HCM, a systemic review and meta-analysis of case-control studies were performed. The following databases were searched to indentify related studies: PubMed database, the Embase database, the Cochrane Central Register of Controlled Trials database, China National Knowledge Information database, and Chinese Scientific and Technological Journal database. Search terms included “hypertrophic cardiomyopathy”, “angiotensin converting enzyme” (ACE) or “ACE” and “polymorphism or mutation”. For the association of AGT M235T polymorphism and HCM, “angiotensin converting enzyme” or “ACE” was replaced with “angiotensinogen”. A total of seventeen studies were included in our review. For the association of ACE I/D polymorphism and HCM, eleven literatures were included in the meta-analysis on association of penetrance and genotype. Similarly, six case-control studies were included in the meta-analysis for AGT M235T. For ACE I/D polymorphism, the comparison of DI/II genotype vs DD genotype was performed in the present meta-analysis. The OR was 0.73 (95% CI: 0.527, 0.998, <i>P</i> = 0.049, power = 94%, alpha = 0.05) after the study which deviated from Hardy-Weinberg Equilibrium was excluded, indicating that the ACE I/D gene polymorphism might be associated with HCM. The AGT M235T polymorphism did not significantly affect the risk of HCM. In addition, ACE I/D gene polymorphism did not significantly influence the interventricular septal thickness in HCM patients. In conclusion, the ACE I/D polymorphism might be associated with the risk of HCM.</p></div

Determination of risk assessment bias by included studies of meta-analysis.

<p>Note, HCM; hypertrophic cardiomyopathy; HWE, Hardy Weinberg Equilibrium.</p

Characteristics of eligible studies in the meta-analysis (AGT M235T).

<p>Note, HCM; hypertrophic cardiomyopathy; HWE, Hardy Weinberg Equilibrium.</p

Meta-analysis of the association between ACE I/D and AGT M235T polymorphisms and HCM penetrance.

<p>OR in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077030#pone-0077030-g002" target="_blank">Fig. 2a</a> indicated that the OR of DI/II vs DD. The pooled OR was 0.73 (95 CI: 0.527, 0.998, <i>P</i> = 0.049). Similarly, OR indicated that the OR of MM/MT vs TT in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077030#pone-0077030-g002" target="_blank">Fig. 2b</a>. HCM, Hypertrophic cardiomyopathy. Fig. 2a, ACE I/D; Fig. 2b, AGT M235T.</p

Characteristics of eligible studies in the meta-analysis (ACE I/D).

<p>Note, HCM; hypertrophic cardiomyopathy; HWE, Hardy Weinberg Equilibrium.</p

SMYD1, an SRF-Interacting Partner, Is Involved in Angiogenesis

<div><p>Previous studies have demonstrated that Smyd1 plays a critical role in cardiomyocyte differentiation, cardiac morphogenesis and myofibril organization. In this study, we uncovered a novel function of Smyd1 in the regulation of endothelial cells (ECs). Our data showed that Smyd1 is expressed in vascular endothelial cells, and knockdown of SMYD1 in endothelial cells impairs EC migration and tube formation. Furthermore, Co-IP and GST pull-down assays demonstrated that SMYD1 is associated with the Serum Response Factor (SRF). EMSA assays further showed that SMYD1 forms a complex with SRF and enhances SRF DNA binding activity. Our studies indicate that SMYD1 serves as an SRF-interacting protein, enhances SRF DNA binding activity, and is required for EC migration and tube formation to regulate angiogenesis.</p></div

SMYD1 expressed in vascular endothelial cells.

<p>(A) RT-PCR analysis of SMYD1 gene expression in HUVEC and HMEC-1 cells. (B) Western blot analysis of endogenous SMYD1 and SRF expression in HUVEC and HMEC-1 cells. Over-expressed Flag-SMYD1 and HA-SRF were used as a positive control to indicate the sizes of SMYD1 or SRF. (C) and (D) Immunohistochemical expression of SRF and SMYD1 in mouse limb buds at E12.5 was shown. Both SMYD1 and SRF were expressed by vascular endothelial cells. Sections were slightly counterstained with hematoxylin.</p

SMYD1 interacts with SRF in cells.

<p>(A) Co-IP experiment in 293T cells. Flag-SMYD1, HA-SRF or null vector (pCMV-HA or pCMV-tg2B) were transfected into 293T cells as indicated and cell lysates were then immunoprecipitated using anti-Flag or anti-HA antibody. The immunoprecipitates were examined by western blotting using anti-HA or anti-Flag antibodies. Input represented 10% of cell lysates used in the Co-IP experiment. (B) SMYD1 co-localization with SRF. Hela cells were transiently transfected with Flag-SMYD1 and HA-SRF. Then, cells were fixed and stained for anti-Flag and anti-HA antibodies. (C) and (D) Mapping of SMYD1 and SRF to identify the SRF or SMYD1-binding region. A total of 293T cells were transfected with Flag-SMYD1 in addition to different HA-SRF deletion mutants as indicated, or cells were transfected with HA-SRF and different Flag-SMYD1 deletion mutants as indicated. Cell lysates were immunoprecipitated with anti-Flag antibody. The immunoprecipitates and cell lysates were then analyzed by western blotting separately using anti-HA antibody, anti-flag antibody for Flag-SMYD1 and its deletion mutants as indicated, and anti-HA antibody for HA-SRF and its deletion mutants as indicated.</p