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Abstract: The pathogens of Alzheimer''s disease (AD) are still unclear, while accumulating evidences have indicated that both genetic and environmental factors are involved in the pathogenesis of AD. Recent studies suggest that AD is primarily a vascular disorder and copper (Cu) may play an important role in AD pathology. However, the consequences of chronic Cu exposure at the presence of other AD risk factors remain to be clarified. To investigate the effects of chronic Cu intake on cerebral hypoperfusion-induced AD pathology, Sprague-Dawley rats suffered bilateral common carotid artery occlusion (2VO) were administrated with 250ppm copper-containing water or not. Morris water maze test showed that Cu exposure for 3 months exacerbated cognitive impairment induced by 2VO. Elevated amyloid precursor protein (APP) and beta-site APP-cleaving enzyme 1 (BACE1) expression in mRNA and protein levels were also observed in brain of Cu-exposed rats suffered 2VO. In contrast, these Cu-exacerbated changes were ameliorated after Cu was withdrawn from drinking water. In summary, our findings demonstrate that chronic Cu exposure might exacerbate AD pathology in 2VO rats. [Copyright &y& Elsevier]

Highlights: [•] In cardiomyocytes, ET-1 treatment resulted in significant upregulation of COX-2 expression and activity. [•] Both COX-2 inhibitors and COX-2 RNA interference suppressed cardiomyocyte hypertrophy induced by ET-1. [•] Calcineurin/NFATc3 signaling pathway participated in the transcriptional regulation of COX-2 by ET-1. [ABSTRACT FROM AUTHOR]

Pathological cardiac hypertrophy often precedes heart failure due to various stimuli, yet effective clinical interventions remain limited. Recently, microRNAs (miRNAs) have been identified as critical regulators of cardiovascular development. In this study, we investigated the role of miR-146b-5p and its underlying mechanisms of action in cardiac hypertrophy. Isoprenaline (ISO) treatment induced significant hypertrophy and markedly enhanced the expression of miR-146b-5p in cultured neonatal rat cardiomyocytes and hearts of C57BL/6 mice. Transfection with the miR-146b-5p mimic led to cardiomyocyte hypertrophy accompanied by autophagy inhibition. Conversely, miR-146b-5p inhibition significantly alleviated ISO-induced autophagy depression, thereby mitigating cardiac hypertrophy both in vitro and in vivo. Our results showed that the autophagy-related mediator double FYVE domain-containing protein 1 (DFCP1) is a target of miR-146b-5p. MiR-146b-5p blocked autophagic flux in cardiomyocytes by suppressing DFCP1, thus contributing to hypertrophy. These findings revealed that miR-146b-5p is a potential regulator of autophagy associated with the onset of cardiac hypertrophy, suggesting a possible therapeutic strategy involving the inhibition of miR-146b-5p. • MiR-146b-5p expression is up-regulated in neonatal rat cardiomyocytes and mice hearts treated with ISO. • MiR-146b-5p targets DFCP1 to impair autophagy, thereby provoking cardiac hypertrophy. • Inhibition of miR-146b-5p attenuates ISO-induced cardiac hypertrophy by restoring DFCP1 and autophagy activity. [ABSTRACT FROM AUTHOR]

Abstract Jumonji domain-containing protein D3 (JMJD3), a histone 3 lysine 27 (H3K27) demethylase, has been extensively studied for their participation in development, cellular physiology and a variety of diseases. However, its potential roles in cardiovascular system remain unknown. In this study, we found that JMJD3 played a pivotal role in the process of cardiac hypertrophy. JMJD3 expression was elevated by isoproterenol (ISO) stimuli both in vitro and in vivo. Overexpression of wild-type JMJD3, but not the demethylase-defective mutant, promoted cardiomyocyte hypertrophy, as implied by increased cardiomyocyte surface area and the expression of hypertrophy marker genes. In contrary, JMJD3 silencing or its inhibitor GSK-J4 suppressed ISO-induced cardiac hypertrophy. Mechanistically, JMJD3 was recruited to demethylate H3K27me3 at the promoter of β-MHC to promote its expression and cardiac hypertrophy. Thus, our results reveal that JMJD3 may be a key epigenetic regulator of β-MHC expression in cardiomyocytes and a potential therapeutic target for cardiac hypertrophy. Graphical abstract Image 1 Highlights • JMJD3 expression was significantly upregulated in ISO-induced cardiac hypertrophy in vitro and in vivo. • JMJD3 depletion or GSK-J4 treatment attenuated the hypertrophic responses stimulated by ISO. • JMJD3 overexpression led to cardiac hypertrophy. • JMJD3 was recruited to and demethylated H3K27me3 at the promoter of β-MHC to promote its expression and cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

The Forkhead box-containing protein, O subfamily 3 (FoxO3) transcription factor negatively regulates myocardial hypertrophy, and its transcriptional activity is finely conditioned by diverse posttranslational modifications, such as phosphorylation, acetylation, ubiquitination, methylation and glycosylation. Here, we introduce a novel modification of the FoxO3 protein in cardiomyocytes: poly(ADP-ribosyl)ation (PARylation) mediated by poly(ADP-ribose) polymerase-1 (PARP1). This process catalyzes the NAD + -dependent synthesis of polymers of ADP-ribose (PAR) and their subsequent attachment to target proteins by PARPs. Primary-cultured neonatal rat cardiomyocytes were incubated with isoproterenol (ISO) to induce hypertrophy, or were infected with recombinant adenovirus vectors harboring PARP1 cDNA (Ad-PARP1). Sprague-Dawley (SD) rats were treated with ISO to induce cardiac hypertrophy, or were injected with Ad-PARP1 into the anterior and posterior left ventricular walls. Cardiomyocyte surface area, the mRNA expression of hypertrophic biomarkers, echocardiography, morphometry of the hearts were measured. The PARP1 activity was tested by cellular PAR levels. Interactions of PARP1 and FoxO3 were investigated by co-immunoprecipitation and immunofluorescence technique. PARylation of FoxO3 mediated by PARP1 facilitated its phosphorylation at the T32, S252 and S314 sites, triggered its nucleus export and suppressed its transcriptional activity and target genes expression, ultimately inducing cardiac hypertrophy. Additionally, PARP1 silencing or specific inhibition by 3-Aminobenzamide (3AB) and veliparib (ABT-888) alleviated the inhibition of FoxO3 activity by ISO, thus suppressing ISO-induced cardiac hypertrophy. Our data provide the first evidence that PARP1 exacerbates cardiac hypertrophy by PARylation of FoxO3. [ABSTRACT FROM AUTHOR]

Objective Tongue squamous cell carcinoma (TSCC) is the most common malignant cancer in the oral cavity, with a high rate of metastasis to the neck lymphoid node. Angiopoietin-like protein 4 (ANGPTL4) and microvessel density (MVD) may be novel indicators for tumor metastasis. The aim of the present study was to investigate the expression and function of ANGPTL4 in TSCC and the relationship between ANGPTL4 and MVD. Methods The expression levels of ANGPTL4 and MVD (CD34) were analyzed in 65 TSCC specimens and the adjacent non-cancerous tissues using immunohistochemistry (IHC). siRNA was delivered into TSCCA cells to downregulate ANGPTL4 expression. Subsequently, validation with real-time RT-PCR and western blot analyses was performed to analyze ANGPTL4 expression levels. In addition, a proliferation assay, migration and invasion assays were carried out. Results ANGPTL4 expression was associated with tumor stage, lymph node metastasis and MVD expression. Cox regression analysis showed that high levels of ANGPTL4 expression were closely associated with poor survival time. In vitro analyses using qRT-PCR and western blot confirmed that ANGPTL4 was successfully inhibited in TSCCA cells. Suppressing ANGPTL4 resulted in the inhibition of cell proliferation and migration, but neither invasion nor cisplatin resistance was significantly affected. Conclusion High expression levels of ANGPTL4 are associated with the T stage, lymphatic metastasis, angiogenesis and poor overall survival in TSCC patients. The downregulation of ANGPTL4 inhibits the migration and proliferation of cells in TSCC. Taken together, ANGPTL4 may serve as a novel biomarker and therapeutic target for TSCC. [ABSTRACT FROM AUTHOR]

Highlights: [•] C/EBPβ expression is upregulated in response to hypertrophic stimulation in vitro and in vivo. [•] C/EBPβ knockdown protects cardiomyocytes from hypertrophy. [•] C/EBPβ knockdown reduced the nuclear translocation of p65-NFκB, and diminished NFκB-DNA binding activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fenofibrate ameliorates cardiac hypertrophy in vivo and in vitro. [•] The interaction between p65-NFκB and NFATc4 regulates cardiac hypertrophy. [•] Fenofibrate attenuates cardiac hypertrophy via activating PPAR-α and thereby preventing the association of p65-NFκB with NFATc4. [Copyright &y& Elsevier]