DFT study on the reaction mechanisms and stereoselectivities of NHC-catalyzed [2 + 2] cycloaddition between arylalkylketenes and electron-deficient benzaldehydes.

In this paper, two possible mechanisms (mechanisms A and B) on the stereoselective [2 + 2] cycloaddition of aryl(alkyl)ketenes and electron-deficient benzaldehydes catalyzed by N-heterocyclic carbenes (NHCs) have been investigated using density functional theory (DFT). Our calculated results indicate that the favorable mechanism (mechanism A) includes three processes: the first step is the nucleophilic attack on the arylalkylketene by the NHC catalyst to form an intermediate, the second step is the [2 + 2] cycloaddition of the intermediate and benzaldehyde for the formation of a ß-lactone, and the last step is the dissociation of the NHC catalyst and the ß-lactone. Notably, the [2 + 2] cycloaddition, in which two chiral centers associated with four configurations (SS, RR, SR and RS) are formed, is demonstrated to be both the rate- and stereoselectivity-determining step. Moreover, the reaction pathway associated with the SR configuration is the most favorable pathway and leads to the main product, which is in good agreement with the experimental results. Furthermore, the analysis of global and local reactivity indexes has been performed to explain the role of the NHC catalyst in the [2 + 2] cycloaddition reaction. Therefore, this study will be of great use for the rational design of more efficient catalysts for this kind of cycloaddition.

Targeting WWP1 ameliorates cardiac ischemic injury by suppressing KLF15-ubiquitination mediated myocardial inflammation.

Rationale: Previous studies have suggested that myocardial inflammation plays a critical role after ischemic myocardial infarction (MI); however, the underlying mechanisms still need to be fully elucidated. WW domain-containing ubiquitin E3 ligase 1 (WWP1) is considered as an important therapeutic target for cardiovascular diseases due to its crucial function in non-ischemic cardiomyopathy, though it remains unknown whether targeting WWP1 can alleviate myocardial inflammation and ischemic injury post-MI. Methods: Recombinant adeno-associated virus 9 (rAAV9)-cTnT-mediated WWP1 or Kruppel-like factor 15 (KLF15) gene transfer and a natural WWP1 inhibitor Indole-3-carbinol (I3C) were used to determine the WWP1 function in cardiomyocytes. Cardiac function, tissue injury, myocardial inflammation, and signaling changes in the left ventricular tissues were analyzed after MI. The mechanisms underlying WWP1 regulation of cardiomyocyte phenotypes in vitro were determined using the adenovirus system. Results: We found that WWP1 expression was up-regulated in cardiomyocytes located in the infarct border at the early phase of MI and in hypoxia-treated neonatal rat cardiac myocytes (NRCMs). Cardiomyocyte-specific WWP1 overexpression augmented cardiomyocyte apoptosis, increased infarct size and deteriorated cardiac function. In contrast, inhibition of WWP1 in cardiomyocytes mitigated MI-induced cardiac ischemic injury. Mechanistically, WWP1 triggered excessive cardiomyocyte inflammation after MI by targeting KLF15 to catalyze K48-linked polyubiquitination and degradation. Ultimately, WWP1-mediated degradation of KLF15 contributed to the up-regulation of p65 acetylation, and activated the inflammatory signaling of MAPK in ischemic myocardium and hypoxia-treated cardiomyocytes. Thus, targeting of WWP1 by I3C protected against cardiac dysfunction and remodeling after MI. Conclusions: Our study provides new insights into the previously unrecognized role of WWP1 in cardiomyocyte inflammation and progression of ischemic injury induced by MI. Our findings afford new therapeutic options for patients with ischemic cardiomyopathy.

The proGnostic role of caRdiac rehAbilitation in patients with left ventriCular anEurysm formation after anterior myocardial infarction (the GRACE study): Study rationale and design of a prospective randomized controlled trial.

Background: Cardiac rehabilitation (CR) is an essential intervention after acute myocardial infarction (MI). However, it is still unclear whether patients with left ventricular aneurysm (LVA) formation after anterior MI would benefit from CR programs. This clinical trial is designed to assess the role of CR in patients with LVA formation after anterior MI. Trial design: The GRACE study is a single-center, single-blind, prospective, randomized controlled clinical trial in China. 100 subjects aged 18-75 years with LVA formation after anterior MI will be recruited and randomized 1:1 to the CR or control group. Both groups will receive standard drug treatment and routine health education according to the guidelines. Participants in the CR group will additionally receive tailored CR programs delivered over a period of 36 sessions. These participants will then be followed up for 1-year. The primary outcome is peak oxygen uptake measured by cardiopulmonary exercise testing after CR programs. The secondary outcomes are cardiac function and EuroQol 5-Dimension-3 Level index scores after CR program and 1-year and major adverse cardiac cerebrovascular events, a composite of cardiovascular mortality, non-fatal MI, non-fatal stroke, malignant arrhythmia or hospitalization for heart failure during the follow-up period. Conclusions: This single-center, single-blind, prospective, randomized controlled clinical trial will determine whether CR improves physical capacity and clinical outcomes in patients with LVA formation after anterior MI. Trial registration: Chinese Clinical Trial Registry ChiCTR2200058852. Registered on 18 April 2022.

Ergosterol Attenuates Isoproterenol-Induced Myocardial Cardiotoxicity.

Phytomedicine has shown a promising potential for the prevention of cardiovascular system diseases and disorders. This study aimed to evaluate protective effect of ergosterol (ER) on isoproterenol (ISO)-induced myocardial cardiotoxicity. We found that pretreatment with ER significantly decreased levels of myocardial CK-MB and LDH, and alleviated myocardial damage induced by ISO in rat model. In addition, ER restored Nrf2 and HO-1 expression and inhibited apoptosis through upregulating Bcl-2 and downregulating Bax, cytochrome c, cleaved caspase-3, caspase-9, and PARP in rat hearts. Hypoxia-reoxygenation model in H9C2 cells confirmed the cardioprotective effects of ER. In conclusion, we provide both in vitro and in vivo evidence that ER significantly enhances Nrf2-mediated anti-oxidative activities, and exerts a protective effect on cardiomyocyte apoptosis. ER could be considered as a potential therapeutic agent to prevent myocardial injury.

Cutoff Value and Long-Term Prediction of Clinical Events by FFR Measured Immediately After Implantation of a Drug-Eluting Stent in Patients With Coronary Artery Disease: 1- to 3-Year Results From the DKCRUSH VII Registry Study.

OBJECTIVES: This study aimed to investigate the cutoff of post-drug-eluting stent (DES) fractional flow reserve (FFR) for prediction of 1- to 3-year target vessel failure (TVF). BACKGROUND: FFR immediately after a DES implantation correlates with clinical events. However, the cutoff of post-DES FFR for predicting long-term clinical events remains understudied. METHODS: Between May 2012 and September 2013, a total of 1,476 patients who had FFR <0.8 at maximal and at baseline underwent DES implantation were prospectively studied in 9 centers. Post-DES FFR was repeat measured. The primary endpoint was the 1-year TVF rate after procedures. Receiver-operating characteristic curves were used to calculate the post-DES FFR value for TVF, then patients were classified on the basis of this value and followed up for 3 years. RESULTS: By the end of the first year, 88 (6.0%) TVFs were recorded. A post-DES FFR ≤0.88 strongly correlated with TVF. Disease in the left anterior descending coronary artery (LAD), stent length, and stent diameter were independent factors of impaired post-DES FFR, whereas post-procedure FFR ≤0.88 was the only predictor of TVF, with 40 (4.0%) TVFs in the FFR >0.88 and 48 (8.0%) in the FFR ≤0.88 group (p = 0.001), mainly driven by target vessel revascularization (3.8% vs. 8.8%; p = 0.005) and cardiac death (0.2% vs. 1.3%; p = 0.017). The difference in TVF between 2 groups was maintained through 3-year follow-up (p = 0.002). For patients with LAD lesions, a post-DES FFR ≤0.905 predicted 1-year TVF. CONCLUSIONS: Post-DES FFR strongly correlated with TVF rate. Mechanisms attributed to and treatments for impaired FFR after stenting should be studied in future studies. (Post-DES FFR Predicts the Clinical Outcomes: DK CRUSH-VII, A Prospective, Multicenter, Registry Study [DK CRUSH-VII]; ChiCTR-PRCH-12001976).

Stent fracture is associated with a higher mortality in patients with type-2 diabetes treated by implantation of a second-generation drug-eluting stent.

Type 2 diabetes correlates with clinical events after the implantation of a second-generation drug-eluting stent (DES). The rate and prognostic value of stent fracture (SF) in patients with diabetes who underwent DES implantation remain unknown. A total of 1160 patients with- and 2251 without- diabetes, who underwent surveillance angiography at 1 year after DES implantation between June 2004 and August 2014, were prospectively studied. The primary endpoints included the incidence of SF and a composite major adverse cardiac event [MACE, including myocardial infarction (MI), cardiac death, and target-vessel revascularization (TVR)] at 1-year follow-up and at the end of follow-up for overall patients, and target lesion failure [TLF, including cardiac death, target vessel myocardial infarction (TVMI) and target lesion revascularization (TLR)] at the end of study for SF patients. In general, diabetes was associated with a higher rate of MACE at 1-year (18.4 vs. 12.9%) and end of follow-up (24.0 vs. 18.6%, all p < 0.001), compared with those in patients who did not have diabetes. The 1-year SF rate was comparable among patients with diabetes (n = 153, 13.2%) and non-diabetic patients (n = 273, 12.1%, p > 0.05). Diabetic patients with SF had a 2.6-fold increase of SF-related cardiac death at the end of study and threefold increase of re-repeat TLR when compared with non-diabetic patients with SF (5.9 vs. 2.2%, p = 0.040; 6.5 vs. 2.2%, p = 0.032), respectively. Given the fact that diabetes is correlated with increased MACE rate, SF in diabetic patients translates into differences in mortality and re-repeat TLR compared with the non-diabetic group.

Incidence and Clinical Outcomes of Stent Fractures on the Basis of 6,555 Patients and 16,482 Drug-Eluting Stents From 4 Centers.

OBJECTIVES: The present study aimed to analyze the incidence of SF and its correlation with clinical events after DES implantation and the outcome of re-intervention for symptomatic in-stent restenosis (ISR) induced by stent fracture (SF). BACKGROUND: SF is associated with a high rate of clinical events after the implantation of drug-eluting stents (DES). However, the chronological rate of SF and the effect of SF on clinical outcomes from a large patient population remain underreported. METHODS: A total of 6,555 patients with 16482 DES in 10751 diseased vessels and surveillance angiography between November 2003 and January 2014 were prospectively studied. The primary endpoints included the incidence of SF, in-stent restenosis (ISR), target lesion revascularization (TLR), and definite stent thrombosis (ST) at the end of follow-up before and after propensity score matching. Clinical outcomes after TLR were also followed up. RESULTS: The SF rate was detected in 803 (12.3%) patients, 3,630 (22.0%) stents, and 1,852 (17.2%) diseased vessels. SF increased over time. SF was associated with higher unadjusted rates of ISR (42.1%), TLR (24.8%, n = 379), and definite ST (4.6%) compared with stents without fracture (10.7%, 6.6%, and 1.03%, all p < 0.001), and the differences remained significant after propensity score matching (all p < 0.05). There was no significant difference in any-cause or cardiac mortality between patients with and without SF. After 1,523 days of follow-up since the first surveillance angiography, repeat ISR was detected in 90 of 379 (23.8%) stents after reintervention, and 6 (7.5%) stents required repeat TLR. CONCLUSIONS: SF is more frequently observed after DES implantation. TLR was required in almost one-fourth of fractured stents. Increased events in the SF group did not translate into a difference in mortality compared with the non-SF group. Reintervention was associated with acceptable clinical results.