Cysteine-Rich Angiogenic Inducer 61 Improves Prognostic Accuracy of GRACE (Global Registry of Acute Coronary Events) 2.0 Risk Score in Patients With Acute Coronary Syndromes

Matricellular protein CCN1 promotes collagen alignment and scar integrity after myocardial infarction

BACKGROUND

Members of the cellular communication network family (CCN) of matricellular proteins, like CCN1, have long been implicated in the regulation of cellular processes underlying wound healing, tissue fibrogenesis, and collagen dynamics. While many studies suggest antifibrotic actions for CCN1 in the adult heart through the promotion of myofibroblast senescence, they largely relied on exogenous supplementation strategies in in vivo models of cardiac injury where its expression is already induced-which may confound interpretation of its function in this process. The objective of this study was to interrogate the role of the endogenous protein on fibroblast function, collagen structural dynamics, and its associated impact on cardiac fibrosis after myocardial infarction (MI).

METHODS/RESULTS

Here, we employed CCN1 loss-of-function methodologies, including both in vitro siRNA-mediated depletion and in vivo fibroblast-specific knockout mice to assess the role of the endogenous protein on cardiac fibroblast fibrotic signaling, and its involvement in acute scar formation after MI. In vitro depletion of CCN1 reduced cardiac fibroblast senescence and proliferation. Although depletion of CCN1 decreased the expression of collagen processing and stabilization enzymes (i.e., P4HA1, PLOD1, and PLOD2), it did not inhibit myofibroblast induction or type I collagen synthesis. Alone, fibroblast-specific removal of CCN1 did not negatively impact ventricular performance or myocardial collagen content but did contribute to disorganization of collagen fibrils and increased matrix compliance. Similarly, Ccn1 ablated animals subjected to MI showed no discernible alterations in cardiac structure or function one week after permanent coronary artery ligation, but exhibited marked increases in incidence of mortality and cardiac rupture. Consistent with our findings that CCN1 depletion does not assuage myofibroblast conversion or type I collagen synthesis in vitro, Ccn1 knockout animals revealed no measurable differences in collagen scar width or mass compared to controls; however, detailed structural analyses via SHG and TEM of scar regions revealed marked alterations in their scar collagen topography-exhibiting changes in numerous macro- and micro-level collagen architectural attributes. Specifically, Ccn1 knockout mice displayed heightened ECM structural complexity in post-MI scar regions, including diminished local alignment and heightened tortuosity of collagen fibers, as well as reduced organizational coherency, packing, and size of collagen fibrils. Associated with these changes in ECM topography with the loss of CCN1 were reductions in fibroblast-matrix interactions, as evidenced by reduced fibroblast nuclear and cellular deformation in vivo and reduced focal-adhesion formation in vitro; findings that ultimately suggest CCN1's ability to influence fibroblast-led collagen alignment may in part be credited to its capacity to augment fibroblast-matrix interactions.

CONCLUSIONS

These findings underscore the pivotal role of endogenous CCN1 in the scar formation process occurring after MI, directing the appropriate arrangement of the extracellular matrix's collagenous components in the maturing scar-shaping the mechanical properties that support its structural stability. While this suggests an adaptive role for CCN1 in regulating collagen structural attributes crucial for supporting scar integrity post MI, the long-term protracted expression of CCN1 holds maladaptive implications, potentially diminishing collagen structural complexity and compliance in non-infarct regions.

IGF2BP1-Mediated Regulation of CCN1 Expression by Specific Binding to G-Quadruplex Structure in Its 3'UTR

The intricate regulation of gene expression is fundamental to the biological complexity of higher organisms, and is primarily governed by transcriptional and post-transcriptional mechanisms. The 3'-untranslated region (3'UTR) of mRNA is rich in cis-regulatory elements like G-quadruplexes (G4s), and plays a crucial role in post-transcriptional regulation. G4s have emerged as significant gene regulators, impacting mRNA stability, translation, and localization. In this study, we investigate the role of a robust parallel G4 structure situated within the 3'UTR of CCN1 mRNA in post-transcriptional regulation. This G4 structure is proximal to the stop codon of human CCN1, and evolutionarily conserved. We elucidated its interaction with the insulin-like growth factor 2 binding protein 1 (IGF2BP1), a noncanonical RNA N6-methyladenosine (m6A) modification reader, revealing a novel interplay between RNA modifications and G-quadruplex structures. Knockdown experiments and mutagenesis studies demonstrate that IGF2BP1 binds specifically to the G4 structure, modulating CCN1 mRNA stability. Additionally, we unveil the role of IGF2BP1's RNA recognition motifs in G4 recognition, highlighting this enthalpically driven interaction. Our findings offer fresh perspectives on the complex mechanisms of post-transcriptional gene regulation mediated by G4 RNA secondary structures.

The Prognostic Value of the Age-D-Dimer-Albumin Score in Patients with Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention

BACKGROUND

 The Age-D-dimer-Albumin (ADA), the CREDO-Kyoto, and the PARIS scores have been established to predict thrombotic events. However, the prognostic performance of these scores compared to the GRACE score in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) has not been reported.

METHODS

 Consecutive AMI patients treated with PCI were retrospectively enrolled at a teaching hospital in China from January 2016 to December 2019. The primary endpoint was all-cause mortality and the secondary endpoint was cardiac death. Harrell's C-index and net reclassification improvement (NRI) were used to compare the prognostic value of these scores with the GRACE score for mortality.

RESULTS

 Of the 1,578 patients enrolled, the mean age was 62.5 years, and 23.5% were female. During a median follow-up of 3.8 years, 146 all-cause deaths and 80 cardiac deaths occurred. The ADA score showed a better prognostic performance than the GRACE (Harrell's C-index: 0.800 vs. 0.749; p = 0.003), the CREDO-Kyoto (Harrell's C-index: 0.800 vs. 0.765; NRI = 0.348, p < 0.001), and the PARIS scores (Harrell's C-index: 0.800 vs. 0.694; NRI = 0.556, p < 0.001). In the multivariable Cox regression analysis, the ADA score was independently associated with all-cause mortality (hazard ratio [HR] = 1.641 per 10-point increment, 95% confidence interval [CI]: 1.397-1.929) and cardiac death (HR = 1.636 per 10-point increment, 95% CI: 1.325-2.020). The risk of all-cause mortality and cardiac death increased with the rising of the ADA score.

CONCLUSION

 The ADA score showed a better prognostic performance than the GRACE, the CREDO-Kyoto, and the PARIS scores in patients with AMI undergoing PCI, which was a potential predictive tool for mortality.

CAROTIDSCORE.RU-The first Russian computer program for risk stratification of postoperative complications of carotid endarterectomy

GOAL

Presentation of the first Russian computer program (www.carotidscore.ru) for risk stratification of postoperative complications of carotid endarterectomy (CEE).

MATERIAL AND METHODS

The present study is based on the analysis of a multicenter Russian database that includes 25,812 patients after CEE operated on from 01/01/2010 to 04/01/2022. The following types of CEE were implemented: 6814 classical CEE with plastic reconstruction of the reconstruction zone with a patch; 18,998 eversion CEE.

RESULTS

In the hospital postoperative period, 0.18% developed a lethal outcome, 0.14%-myocardial infarction, 0.35%-stroke. The combined endpoint was 0.68%. For each factor present in patients, a predictive coefficient was calculated. The prognostic coefficient was a numerical indicator reflecting the strength of the influence of each factor on the development of postoperative complications. Based on this formula, predictive coefficients were calculated for each factor present in patients in our study. The total contribution of these factors was reflected in "%" and denoted the risk of postoperative complications with a minimum value of 0% and a maximum of 100%. On the basis of the obtained calculations, a computer program CarotidSCORE was created. Its graphical interface is based on the QT framework (https://www.qt.io), which has established itself as one of the best solutions for desktop applications. It is possible not only to calculate the probability of developing a complication, but also to save all data about the patient in JSON format (for the patient's personal card and his anamnesis). The CarotidSCORE program contains 47 patient parameters, including clinical-demographic, anamnestic and angiographic characteristics. It allows you to choose one of the four types of CEE, which will provide an accurate stratification of the risk of complications for each of them in person.

CONCLUSION

CarotidSCORE (www.carotidscore.ru) is able to determine the likelihood of postoperative complications in patients undergoing CEE.

Use of serial changes in biomarkers vs. baseline levels to predict left ventricular remodelling after STEMI

AIMS

Cellular communication network factor 1 (CCN1) is an independent predictor of MACE after ACS and elevated levels correlated with infarct size after STEMI. We compared the prognostic accuracy of baseline levels of CCN1, NT-proBNP, hsTnT, and ST2 and changes in levels over time to predict the development of structural and functional alterations typical of LV remodelling.

METHODS

Serial 3-T cMRI scans were performed to determine LVEF, LVEDV, LVESV, infarct size, and relative infarct size, which were correlated with serial measurements of the four biomarkers. The prognostic significance of these biomarkers was assessed by multiple logistic regression analysis by examining their performance in predicting dichotomized cardiac MRI values 12 months after STEMI based on their median. For each biomarker three models were created using baseline (BL), the Δ value (BL to 6 months), and the two values together as predictors. All models were adjusted for age and renal function. Receiver operator curves were plotted with area under the curve (AUC) to discriminate the prognostic accuracy of individual biomarkers for MRI-based structural or functional changes.

RESULTS

A total of 44 predominantly male patients (88.6%) from the ETiCS (Etiology, Titre-Course, and Survival) study were identified at a mean age of 55.5 ± 11.5 (SD) years treated by successful percutaneous coronary intervention (97.7%) at a rate of 95.5% stent implantation within a median pain-to-balloon time of 260 min (IQR 124-591). Biomarkers hsTnT and ST2 were identified as strong predictors (AUC > 0.7) of LVEDV and LVEF. BL measurement to predict LVEF [hsTnT: AUC 0.870 (95% CI: 0.756-0.983), ST2: AUC 0.763 (95% CI: 0.615-0.911)] and the Δ value BL-6M [hsTnT: AUC 0.870 (95% CI: 0.756-0.983), ST2: AUC 0.809 (95% CI: 0.679-0.939)] showed a high prognostic value without a significant difference for the comparison of the BL model vs. the Δ-value model (BL-6M) for hsTnT (P = 1) and ST2 (P = 0.304). The combined model that included baseline and Δ value as predictors was not able to improve the ability to predict LVEF [hsTnT: AUC 0.891 (0.791-0.992), P = 0.444; ST2: AUC 0.778 (0.638-0.918), P = 0.799]. Baseline levels of CCN1 were closely associated with LVEDV at 12 months [AUC 0.708 (95% CI: 0.551-0.865)] and infarct size [AUC 0.703 (95% CI: 0.534-0.872)].

CONCLUSIONS

Baseline biomarker levels of hsTnT and ST2 were the strongest predictors of LVEF and LVEDV at 12 months after STEMI. The association of CCN1 with LVEDV and infarct size warrants further study into the underlying pathophysiology of this novel biomarker.