Crotonylation of NAE1 Modulates Cardiac Hypertrophy via Gelsolin Neddylation.

BACKGROUND: Cardiac hypertrophy and its associated remodeling are among the leading causes of heart failure. Lysine crotonylation is a recently discovered posttranslational modification whose role in cardiac hypertrophy remains largely unknown. NAE1 (NEDD8-activating enzyme E1 regulatory subunit) is mainly involved in the neddylation modification of protein targets. However, the function of crotonylated NAE1 has not been defined. This study aims to elucidate the effects and mechanisms of NAE1 crotonylation on cardiac hypertrophy. METHODS: Crotonylation levels were detected in both human and mouse subjects with cardiac hypertrophy through immunoprecipitation and Western blot assays. TMT-labeled quantitative lysine crotonylome analysis was performed to identify the crotonylated proteins in a mouse cardiac hypertrophic model induced by transverse aortic constriction. We generated NAE1 knock-in mice carrying a crotonylation-defective lysine to arginine K238R (lysine to arginine mutation at site 238) mutation (NAE1 K238R) and NAE1 knock-in mice expressing a crotonylation-mimicking lysine to glutamine K238Q (lysine to glutamine mutation at site 238) mutation (NAE1 K238Q) to assess the functional role of crotonylation of NAE1 at K238 in pathological cardiac hypertrophy. Furthermore, we combined coimmunoprecipitation, mass spectrometry, and dot blot analysis that was followed by multiple molecular biological methodologies to identify the target GSN (gelsolin) and corresponding molecular events contributing to the function of NAE1 K238 crotonylation. RESULTS: The crotonylation level of NAE1 was increased in mice and patients with cardiac hypertrophy. Quantitative crotonylomics analysis revealed that K238 was the main crotonylation site of NAE1. Loss of K238 crotonylation in NAE1 K238R knock-in mice attenuated cardiac hypertrophy and restored the heart function, while hypercrotonylation mimic in NAE1 K238Q knock-in mice significantly enhanced transverse aortic constriction-induced pathological hypertrophic response, leading to impaired cardiac structure and function. The recombinant adenoviral vector carrying NAE1 K238R mutant attenuated, while the K238Q mutant aggravated Ang II (angiotensin II)-induced hypertrophy. Mechanistically, we identified GSN as a direct target of NAE1. K238 crotonylation of NAE1 promoted GSN neddylation and, thus, enhanced its protein stability and expression. NAE1 crotonylation-dependent increase of GSN promoted actin-severing activity, which resulted in adverse cytoskeletal remodeling and progression of pathological hypertrophy. CONCLUSIONS: Our findings provide new insights into the previously unrecognized role of crotonylation on nonhistone proteins during cardiac hypertrophy. We found that K238 crotonylation of NAE1 plays an essential role in mediating cardiac hypertrophy through GSN neddylation, which provides potential novel therapeutic targets for pathological hypertrophy and cardiac remodeling.

HNEAP Regulates Necroptosis of Cardiomyocytes by Suppressing the m5 C Methylation of Atf7 mRNA.

PIWI-interacting RNAs (piRNAs) are highly expressed in various cardiovascular diseases. However, their role in cardiomyocyte death caused by ischemia/reperfusion (I/R) injury, especially necroptosis, remains elusive. In this study, a heart necroptosis-associated piRNA (HNEAP) is found that regulates cardiomyocyte necroptosis by targeting DNA methyltransferase 1 (DNMT1)-mediated 5-methylcytosine (m5 C) methylation of the activating transcription factor 7 (Atf7) mRNA transcript. HNEAP expression level is significantly elevated in hypoxia/reoxygenation (H/R)-exposed cardiomyocytes and I/R-injured mouse hearts. Loss of HNEAP inhibited cardiomyocyte necroptosis and ameliorated cardiac function in mice. Mechanistically, HNEAP directly interacts with DNMT1 and attenuates m5 C methylation of the Atf7 mRNA transcript, which increases Atf7 expression level. ATF7 can further downregulate the transcription of Chmp2a, an inhibitor of necroptosis, resulting in the reduction of Chmp2a level and the progression of cardiomyocyte necroptosis. The findings reveal that piRNA-mediated m5 C methylation is involved in the regulation of cardiomyocyte necroptosis. Thus, the HNEAP-DNMT1-ATF7-CHMP2A axis may be a potential target for attenuating cardiac injury caused by necroptosis in ischemic heart disease.

PIWI-Interacting RNA HAAPIR Regulates Cardiomyocyte Death After Myocardial Infarction by Promoting NAT10-Mediated ac4 C Acetylation of Tfec mRNA.

PIWI-interacting RNAs (piRNAs) are abundantly expressed in heart. However, their functions and molecular mechanisms during myocardial infarction remain unknown. Here, a heart-apoptosis-associated piRNA (HAAPIR), which regulates cardiomyocyte apoptosis by targeting N-acetyltransferase 10 (NAT10)-mediated N4-acetylcytidine (ac4 C) acetylation of transcription factor EC (Tfec) mRNA transcript, is identified. HAAPIR deletion attenuates ischemia/reperfusion induced myocardial infarction and ameliorate cardiac function compared to WT mice. Mechanistically, HAAPIR directly interacts with NAT10 and enhances ac4 C acetylation of Tfec mRNA transcript, which increases Tfec expression. TFEC can further upregulate the transcription of BCL2-interacting killer (Bik), a pro-apoptotic factor, which results in the accumulation of Bik and progression of cardiomyocyte apoptosis. The findings reveal that piRNA-mediated ac4 C acetylation mechanism is involved in the regulation of cardiomyocyte apoptosis. HAAPIR-NAT10-TFEC-BIK signaling axis can be potential target for the reduction of myocardial injury caused by cardiomyocyte apoptosis in ischemia heart diseases.

Analysis of risk factors for early stent thrombosis in the Chinese population: A multicenter restrospective study.

BACKGROUND: The predictive scoring systems for early stent thrombosis (EST) remains blank in China. The study aims to evaluate the risk factors and conduct a prediction model of EST in the Chinese population. METHODS: EST was defined as thrombosis that occurs within the first 30 days after primary percutaneous coronary intervention (PCI). Patients from ten Chinese hospitals diagnosed as stent thrombosis (ST) from January 2010 to December 2016 were retrospectively included as the study group. A control group (1 case:2 controls) was created by including patients without ST, major adverse cardiovascular events, or cerebrovascular events during follow-up. The present study evaluated 426 patients with single-vessel lesions and ultimately included 40 patients with EST and 80 control patients, who were included to identify factors that predicted EST and to develop a prediction scoring system. The other 171 patients without integrated 1:2 pair were used for external validation. RESULTS: EST was independently associated with a low hemoglobin concentration (adjusted odds ratio [OR] 0.946, 95% confidence interval [95% CI] 0.901-0.993, P=0.026), a high pre-PCI Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score (OR 1.166, 95% CI 1.049-1.297, P=0.004), and a DAPT (DAPT) duration of <30 days (OR 28.033, 95% CI 5.302-272.834, P<0.001). The simple EST prediction score provided an area under the curve (AUC) of 0.854 (95% CI 0.777-0.932, P<0.001) with 70.0% sensitivity and 90.0% specificity, and 0.742 (95% CI 0.649-0.835, P<0.001) with 54.5% sensitivity and 81.0% specificity for external validation dataset. CONCLUSIONS: EST may be independently associated with DAPT discontinuation within 30 days, a low hemoglobin concentration, and a high SYNTAX score. The scoring system also has a good ability to predict the risk of EST and may be useful in the clinical setting.

Application of targeted therapy strategies with nanomedicine delivery for atherosclerosis.

Atherosclerosis (AS) is the main pathological cause of coronary heart disease (CHD). Current clinical interventions including statin drugs can effectively reduce acute myocardial infarction and stroke to some extent, but residual risk remains high. The current clinical treatment regimens are relatively effective for early atherosclerotic plaques and can even reverse their progression. However, the effectiveness of these treatments for advanced AS is not ideal, and advanced atherosclerotic plaques-the pathological basis of residual risk-can still cause a recurrence of acute cardiovascular and cerebrovascular events. Recently, nanomedicine-based treatment strategies have been extensively used in antitumor therapy, and also shown great potential in anti-AS therapy. There are many microstructures in late-stage atherosclerotic plaques, such as neovascularization, micro-calcification, and cholesterol crystals, and these have become important foci for targeted nanomedicine delivery. The use of targeted nanoparticles has become an important strategy for the treatment of advanced AS to further reduce the residual risk of cardiovascular events. Furthermore, the feasibility and safety of nanotechnology in clinical treatment have been preliminarily confirmed. In this review, we summarize the application of nanomedicine delivery in the treatment of advanced AS and the clinical value of several promising nanodrugs.

Association Between Vitamin D and Hyperuricemia Among Adults in the United States.

Background: Serum uric acid can act as a risk factor for cardiovascular disease (CVD) and as antioxidant defense. Vitamin D deficiency can activate the parathyroid to induce the release of parathyroid hormone, which was thought to increase serum uric acid level, and low vitamin D status may also be associated with risk of CVD. No known studies have explored the association between serum 25(OH) D, vitamin D intake, and HU for the American population. Methods: We extracted 15,723 US adults aged 20-85 years from the National Health and Nutrition Examination Survey (NHANES) in 2007-2014. All dietary intakes were evaluated through 24-h dietary recalls. Multivariable logistic regression analysis was performed to examine the associations after adjustment for confounders. Results: Compared to the lowest quintile (Q1), for males, adjusted odds ratios (ORs) of HU in Q2 to Q4 of serum 25(OH) D levels were 0.78 (95% CI, 0.65-0.93), 0.97 (0.81-1.16), and 0.72 (0.60-0.88); ORs in Q2-Q5 of total vitamin D intake were 0.83 (0.69-0.98), 0.69 (0.58-0.83), 0.66 (0.55-0.79), and 0.59 (0.48-0.71), respectively. In females, OR was 0.80 (0.66-0.97) of serum 25(OH) D for Q3, and ORs in Q5 of total vitamin D intake were 0.80 (0.65-0.98). Conclusions: Our findings indicated that the serum 25(OH) D intakes of dietary vitamin D, supplemental vitamin D, and total vitamin D were inversely associated with HU in males. In females, a lower risk of HU with higher serum 25(OH) D, dietary vitamin D, and total vitamin D intake was found, but with no association between supplemental vitamin D intake and the risk of HU.

Comprehensive circRNA expression profile and construction of circRNA-related ceRNA network in cardiac fibrosis.

Cardiac fibrosis is a common pathological condition that contributes to the progression of many cardiac diseases. Circular RNAs (circRNAs) are emerging as new regulators of cardiac fibrosis. However, the expression and function of circRNAs in cardiac fibrosis remain largely unknown. The present study aims to investigate the circRNA expression profile and identify the roles of circRNAs in cardiac fibrosis. Transforming growth factor-ß1 (TGF-ß1) was used to establish an in vitro model of cardiac fibrosis in cardiac fibroblasts. CircRNA sequencing revealed that a total of 283 circRNAs were aberrantly expressed in fibrotic cardiac fibroblasts, with 79 upregulated and 204 downregulated. The expression changes of randomly selected circRNAs were validated by real-time PCR. A circRNA-based competing endogenous RNA network 1755 nodes and 30394 edges was established, and module analysis was conducted using the plug-in MCODE. KEGG pathway enrichment analysis was performed for mRNAs involved in the top three enriched modules. The results showed that these mRNAs were enriched in cardiac fibrosis-related signalling pathways, including the 'TGF-beta signaling pathway', 'MAPK signaling pathway', 'AMPK signaling pathway', and 'PI3K-Akt signaling pathway'. The predicted ceRNAs and bioinformatics analysis revealed the potential role of circRNAs in cardiac fibrosis, which would provide useful information for understanding the mechanism and finding effective prevention and treatment targets for cardiac fibrosis.