Malat1 promotes macrophage-associated inflammation by increasing PPAR-γ methylation through binding to EZH2 in acute myocardial infarction.

The inflammatory microenvironment of macrophage plays an important role in acute myocardial infarction (AMI), but the regulatory mechanism is unknown. Here, we aimed to investigate the role of Malat1 on inflammation microenvironment of macrophage in AMI. Our study found that Malat1 expression was increased in AMI, which mainly expressed in macrophages. Malat1 inhibition improved collagen deposition and inflammation in infarcted heart. In vitro, Malat1 inhibition evidently reduced macrophage-associated inflammation. The results from ribonucleic acid pull-down (RNA pull-down) and RNA Immunoprecipitation (RIP) assay demonstrated that Malat1 directly binds to EZH2. Malat1 and EZH2 complex could increase histone H3K27me3 expression and further inhibit the production of PPAR-γ. In vivo, inhibition of Malat1 also leaded to the down-regulation of both EZH2 and H3K27me3, as well as up-regulation of PPAR-γ in infarcted heart. Therefore, these findings demonstrate a novel mechanism of Malat1 on inflammation microenvironment of macrophage in AMI, which provide a new target for its treatment.

Hesperetin attenuates LPS-induced the inflammatory response and apoptosis of H9c2 by activating the AMPK/P53 signaling pathway.

INTRODUCTION: Hesperetin (HES), whose main pharmacological effects are anti-inflammatory and cardioprotective properties. In our study, we investigated the role of HES in lipopolysaccharide (LPS)-induced inflammation and apoptosis in H9c2 cells. METHODS: Cell viability was assessed through MTT assay. Tumor necrosis factor (TNF)-α and interleukin (IL)-ß expression were quantified through RT-qPCR assay. Secondly, the apoptosis rate was assessed by Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Finally, B-cell lymphoma 2 (Bcl-2)- associated X protein (Bax), adenosine monophosphate-activated protein kinase (AMPK), and P53 expression were quantified through western blot assay. RESULTS: Our results demonstrated that LPS stimulation decreased the cell viability, increased IL-1ß and TNF-α expression in H9c2 cells. However, HES treatment significantly increased the cell viability, decreased IL-1ß and TNF-α expression in LPS-induced H9c2 cells. In addition, HES significantly increased the phosphorylation level of AMPK. Meanwhile, HES prevented against LPS-mediated the P53 and Bax protein upregulation, and Bcl-2 protein downregulation in H9c2 cells. More interestingly, compound C (an AMPK inhibitor) treatment eliminated the protective effects of HES. CONCLUSION: Our findings revealed that HES attenuated the LPS-mediated inflammation and apoptosis of H9c2 cells by activating the AMPK/P53 signaling pathway, suggesting that HES may be a potential cardioprotective agent.

GAS5 silencing attenuates hypoxia-induced cardiomyocytes injury by targeting miR-21/PTEN.

INTRODUCTION: Myocardial hypoxia is an important factor causing myocardial infarction (MI). Interestingly, many unknown factors in the molecular mechanism of MI remain unclear. Our study explored the role of lncRNA growth arrest-specific 5 (GAS5) in cell injury under hypoxia. METHODS: AS5 expression was assessed in MI and human cardiomyocytes under hypoxia through RT-qPCR assay. Methyl thiazolyl tetrazolium assay, flow cytometry assay, and transwell assay was carried out for cell viability, cell apoptosis, cell migration, and invasion, respectively. The regulatory target of GAS5 was explored through a dual-luciferase reporter assay. RESULTS: Our findings indicated that the upregulation of GAS5 was related to hypoxia. Downregulation of GAS5 expression could decrease hypoxia-induced cell apoptosis and increase cell migration and invasion. Moreover, GAS 5 targeted miR-21, which regulated the phosphatase and tension homology deleted on chromosome ten gene (PTEN) expression. Furthermore, the knockdown of miR-21 eliminated the effect of GAS5 silencing on cell injury. CONCLUSION: These results indicated that lncRNA GAS5 silencing decreased cardiomyocyte injury by hypoxia-induced through regulating miR-21/PTEN.

Associated factors for prenatally diagnosed fetal congenital heart diseases.

OBJECTIVE: Current studies have suggested that fetal congenital heart diseases (CHDs) are caused by various factors. However, few data in this field is available in China. This study aimed to detect associated factors of prenatally diagnosed fetal CHD in a large sample in China. STUDY DESIGN: Pregnant women who underwent fetal echocardiography were recruited in our hospital between May 2018 and September 2019. The maternal sociodemographic and lifestyle characteristics and some fetal factors were obtained. We used forward stepwise logistic regression analysis to assess risk of fetal CHD associated with various factors. RESULTS: A total of 5024 subjects were enrolled, of whom 875 had CHD fetuses. Among the fetal CHD group (N = 875), critical CHDs account for 27%, of which Tetralogy of Fallot is the most (7.1%), followed by coarctation of aorta (4.0%), double-outlet right ventricle (2.9%). The forward stepwise logistic regression models revealed that history of spontaneous abortion (OR = 1.59, 95% CI 1.33-1.91, P = 0.000), upper respiratory tract infection during early pregnancy (OR = 1.30, 95% CI 1.04-1.62, P = 0.020), mental stress during early pregnancy (OR = 2.37, 95% CI 1.15-4.91, P = 0.020), single umbilical artery (OR = 2.30, 95% CI 1.18-4.51, P = 0.015), and paternal smoking (OR = 1.21, 95% CI 1.02-1.44, P = 0.027) are positively associated with an increased risk of fetal CHD. CONCLUSION: We identified several factors positively associated with fetal CHD. These findings suggest that it is important to strengthen healthcare and prenatal counseling for women with these factors.

Coordination of PRKCA/PRKCA-AS1 interplay facilitates DNA methyltransferase 1 recruitment on DNA methylation to affect protein kinase C alpha transcription in mitral valve of rheumatic heart disease.

In the present study, mitral valve tissues from three mitral stenosis patients with RHD by valve replacement and two healthy donors were harvested and conducted DNA methylation signature on PRKCA by MeDIP-qPCR. The presence of hypomethylated CpG islands at promoter and 5' terminal of PRKCA was observed in RHD accompanied with highly expressed PRKCA and down-regulated antisense long non-coding RNA (lncRNA) PRKCA-AS1 compared to health control. Furthermore, the enrichments of DNMT1/3A/3B on PRKCA were detected by ChIP-qPCR assay in vivo and in human cardiomyocyte AC16 and RL-14 cells exposed to TNF-α in vitro, and both demonstrated that DNMT1 substantially contributed to DNA methylation. Additionally, PRKCA-AS1 was further determined to bind with promoter of PRKCA via 5' terminal and interact with DNMT1 via 3' terminal. Taken together, our results illuminated a novel regulatory mechanism of DNA methylation on regulating PRKCA transcription through lncRNA PRKCA-AS1, and shed light on the molecular pathogenesis of RHD occurrence.

Simple analysis of four bisphosphonates simultaneously by reverse phase liquid chromatography using n-amylamine as volatile ion-pairing agent.

Volatile organic amine was used as the mobile phase addictive during the separation of four bisphosphonates (alendronate, pamidronate, zoledronic acid and etidronate). An isocratic liquid chromatography method with evaporative light-scattering detection (ELSD) was developed for these bisphosphonates which are not retained on non-polar column and lack chromophore for detection. The analytes have sufficiently separated from each other on a Phenomenex C18 column. The effects of mobile phase composition and instrumental parameters of ELSD were studied. This newly developed method enables direct measurement for analysis of bisphosphonates without the need of derivatization. This developed method provides high separation and specificity to bisphosphonate analysis. In quantitative analysis, the method showed satisfactory precision (less than 2.8%) and accuracy (higher than 94.4%), good linearity (r=0.9991-0.9997) and sufficient sensitivity (15-18 microg/ml). It can be easily and conveniently adopted for the routine quality control analysis.