Extracellular Matrix in Heart Failure: Role of ADAMTS5 in Proteoglycan Remodeling.

BACKGROUND: Remodeling of the extracellular matrix (ECM) is a hallmark of heart failure (HF). Our previous analysis of the secretome of murine cardiac fibroblasts returned ADAMTS5 (a disintegrin and metalloproteinase with thrombospondin motifs 5) as one of the most abundant proteases. ADAMTS5 cleaves chondroitin sulfate proteoglycans such as versican. The contribution of ADAMTS5 and its substrate versican to HF is unknown. METHODS: Versican remodeling was assessed in mice lacking the catalytic domain of ADAMTS5 (Adamts5ΔCat). Proteomics was applied to study ECM remodeling in left ventricular samples from patients with HF, with a particular focus on the effects of common medications used for the treatment of HF. RESULTS: Versican and versikine, an ADAMTS-specific versican cleavage product, accumulated in patients with ischemic HF. Versikine was also elevated in a porcine model of cardiac ischemia/reperfusion injury and in murine hearts after angiotensin II infusion. In Adamts5ΔCat mice, angiotensin II infusion resulted in an aggravated versican build-up and hyaluronic acid disarrangement, accompanied by reduced levels of integrin ß1, filamin A, and connexin 43. Echocardiographic assessment of Adamts5ΔCat mice revealed a reduced ejection fraction and an impaired global longitudinal strain on angiotensin II infusion. Cardiac hypertrophy and collagen deposition were similar to littermate controls. In a proteomics analysis of a larger cohort of cardiac explants from patients with ischemic HF (n=65), the use of ß-blockers was associated with a reduction in ECM deposition, with versican being among the most pronounced changes. Subsequent experiments in cardiac fibroblasts confirmed that ß1-adrenergic receptor stimulation increased versican expression. Despite similar clinical characteristics, patients with HF treated with ß-blockers had a distinct cardiac ECM profile. CONCLUSIONS: Our results in animal models and patients suggest that ADAMTS proteases are critical for versican degradation in the heart and that versican accumulation is associated with impaired cardiac function. A comprehensive characterization of the cardiac ECM in patients with ischemic HF revealed that ß-blockers may have a previously unrecognized beneficial effect on cardiac chondroitin sulfate proteoglycan content.

Analysis of Mitochondrial Proteins in the Surviving Myocardium after Ischemia Identifies Mitochondrial Pyruvate Carrier Expression as Possible Mediator of Tissue Viability.

The endogenous mechanisms contributing to tissue survival following myocardial infarction are not fully understood. We investigated the alterations in the mitochondrial proteome after ischemia-reperfusion (I/R) and its possible implications on cell survival. Mitochondrial proteomic analysis of cardiac tissue from an in vivo porcine I/R model found that surviving tissue in the peri-infarct border zone showed increased expression of several proteins. Notably, these included subunits of the mitochondrial pyruvate carrier (MPC), namely MPC1 and MPC2. Western blot, immunohistochemistry, and mRNA analysis corroborated the elevated expression of MPC in the surviving tissue. Furthermore, MPC1 and MPC2 protein levels were found to be markedly elevated in the myocardium of ischemic cardiomyopathy patients. These findings led to the hypothesis that increased MPC expression is cardioprotective due to enhancement of mitochondrial pyruvate uptake in the energy-starved heart following I/R. To test this, isolated mouse hearts perfused with a modified Krebs buffer (containing glucose, pyruvate, and octanoate as metabolic substrates) were subjected to I/R with or without the MPC transport inhibitor UK5099. UK5099 increased myocardial infarction and attenuated post-ischemic recovery of left ventricular end-diastolic pressure. However, aerobically perfused control hearts that were exposed to UK5099 did not modulate contractile function, although pyruvate uptake was blocked as evidenced by increased cytosolic lactate and pyruvate levels. Our findings indicate that increased expression of MPC leads to enhanced uptake and utilization of pyruvate during I/R. We propose this as a putative endogenous mechanism that promotes myocardial survival to limit infarct size.

The addition of albumin improves Schwann cells viability in nerve cryopreservation.

The purpose of the current study was to establish a valid protocol for nerve cryopreservation, and to evaluate if the addition of albumin supposed any advantage in the procedure. We compared a traditional cryopreservation method that uses dimethyl sulfoxide (DMSO) as cryoprotectant, to an alternative method that uses DMSO and albumin. Six Wistar Lewis rats were used to obtain twelve 20 mm fragments of sciatic nerve. In the first group, six fragments were cryopreserved in 199 media with 10% DMSO, with a temperature decreasing rate of 1 °C per minute. In the second group, six fragments were cryopreserved adding 4% human albumin. The unfreezing process consisted of sequential washings with saline in the first group, and saline and 20% albumin in the second group at 37 °C until the crioprotectant was removed. Structural evaluation was performed through histological analysis and electronic microscopy. The viability was assessed with the calcein-AM (CAM) and 4',6-diamino-2-fenilindol (DAPI) staining. Histological results showed a correct preservation of peripheral nerve architecture and no significant differences were found between the two groups. However, Schwann cells viability showed in the CAM-DAPI staining was significantly superior in the albumin group. The viability of Schwann cells was significantly increased when albumin was added to the nerve cryopreservation protocol. However, no significant structural differences were found between groups. Further studies need to be performed to assess the cryopreserved nerve functionality using this new method.

Glycoproteomics Reveals Decorin Peptides With Anti-Myostatin Activity in Human Atrial Fibrillation.

BACKGROUND: Myocardial fibrosis is a feature of many cardiac diseases. We used proteomics to profile glycoproteins in the human cardiac extracellular matrix (ECM). METHODS: Atrial specimens were analyzed by mass spectrometry after extraction of ECM proteins and enrichment for glycoproteins or glycopeptides. RESULTS: ECM-related glycoproteins were identified in left and right atrial appendages from the same patients. Several known glycosylation sites were confirmed. In addition, putative and novel glycosylation sites were detected. On enrichment for glycoproteins, peptides of the small leucine-rich proteoglycan decorin were identified consistently in the flowthrough. Of all ECM proteins identified, decorin was found to be the most fragmented. Within its protein core, 18 different cleavage sites were identified. In contrast, less cleavage was observed for biglycan, the most closely related proteoglycan. Decorin processing differed between human ventricles and atria and was altered in disease. The C-terminus of decorin, important for the interaction with connective tissue growth factor, was detected predominantly in ventricles in comparison with atria. In contrast, atrial appendages from patients in persistent atrial fibrillation had greater levels of full-length decorin but also harbored a cleavage site that was not found in atrial appendages from patients in sinus rhythm. This cleavage site preceded the N-terminal domain of decorin that controls muscle growth by altering the binding capacity for myostatin. Myostatin expression was decreased in atrial appendages of patients with persistent atrial fibrillation and hearts of decorin null mice. A synthetic peptide corresponding to this decorin region dose-dependently inhibited the response to myostatin in cardiomyocytes and in perfused mouse hearts. CONCLUSIONS: This proteomics study is the first to analyze the human cardiac ECM. Novel processed forms of decorin protein core, uncovered in human atrial appendages, can regulate the local bioavailability of antihypertrophic and profibrotic growth factors.

Tissue engineering for neurodegenerative diseases using human amniotic membrane and umbilical cord.

Regenerative medicine, based on the use of stem cells, scaffolds and growth factors, has the potential to be a good approach for restoring damaged tissues of the central nervous system. This study investigated the use of human amniotic mesenchymal stem cells (hAMSC), human amniotic epithelial stem cells (hAESC), and human Wharton's jelly mesenchymal stem cells (hWJMSC) derived from human umbilical cord as a source of stem cells, and the potential of the human amniotic membrane (HAM) as a scaffold and/or source of growth factors to promote nerve regeneration. The hAMSC and hAESC obtained from HAM and the hWJMSC from umbilical cords were cultured in induction medium to obtain neural-like cells. The morphological differentiation of hAMSC, hAESC and hWJMSC into neural-like cells was evident after 4-5 days, when they acquired an elongated and multipolar shape, and at 21 days, when they expressed neural and glial markers. On other way, the HAM was completely decellularized without affecting the components of the basement membrane or the matrix. Subsequently, hAMSC, hAESC and hWJMSC differentiated into neural-like cells were seeded onto the decellularized HAM, maintaining their morphology. Finally, conditioned media from the HAM allowed proliferation of hAMSC, hAESC and hWJMSC differentiated to neural-like cells. Both HAM and umbilical cord are biomaterials with great potential for use in regenerative medicine for the treatment of neurodegenerative diseases.

Production of an acellular matrix from amniotic membrane for the synthesis of a human skin equivalent.

Human amniotic membrane (HAM) has useful properties as a dermal matrix substitute. The objective of our work was to obtain, using different enzymatic or chemical treatments to eliminate cells, a scaffold of acellular HAM for later use as a support for the development of a skin equivalent. The HAM was separated from the chorion, incubated and cryopreserved. The membrane underwent different enzymatic and chemical treatments to eliminate the cells. Fibroblasts and keratinocytes were separately obtained from skin biopsies of patients following a sequential double digestion with first collagenase and then trypsin-EDTA (T/E). A skin equivalent was then constructed by seeding keratinocytes on the epithelial side and fibroblasts on the chorionic side of the decellularizated HAM. Histological, immunohistochemical, inmunofluorescent and molecular biology studies were performed. Treatment with 1% T/E at 37 °C for 30 min totally removed epithelial and mesenchymal cells. The HAM thus treated proved to be a good matrix to support adherence of cells and allowed the achievement of an integral and intact scaffold for development of a skin equivalent, which could be useful as a skin substitute for clinical use.

Cryoconservation of peptide extracts from trypsin digestion of proteins for proteomic analysis in a hospital biobank facility.

We tested a semiautomated protocol for the proper storage and conservation in a hospital biobank of tryptic peptide extracts coming from samples with low and high protein complexity for subsequent mass spectrometry analysis. Low-complexity samples (serum albumin, serotransferrin. and alpha-S1-casein) were loaded in replicates in SDS-PAGE and subjected to standard in-gel trypsin digestion. For LC-MALDI-TOF/TOF analysis, purified ß-galactosidase and human serum samples were in-solution digested following standard procedures and desalted with C18 stage-tips. In both cases, peptides extracts were aliquoted in individually 2D coded tubes, vacuum-dried, barcode-read, and stored in an automated -20 °C freezer in the Biobank facility. Samples were kept dried at -20 °C until the corresponding time-point of analysis, then reconstituted in the proper buffer and analyzed by either MALDI-TOF/TOF (peptide fingerprinting and MS/MS) or LC-MALDI-TOF/TOF following a highly reproducible pattern to ensure the reproducibility of the results. Protein identification was done with either Mascot or Protein Pilot as search engines using constant parameters. Over a period of 1 year we checked six different time points at days 0, 7, 30, 90, 180, and 365. We compared MS and MS/MS protein score, number of identified peptides, and coverage of the identified proteins. In the low complexity samples, the number of peptides detected gradually decreased over time, especially affecting the MS score. However, two of the three proteins - serum albumin and serotransferrin - were identified by both PMF and MS/MS at day 90. By day 180, only MS/MS identification in some replicates was possible. By LC-MS/MS, ß-galactosidase and the most abundant serum proteins were identified with good scores at all time points even by day 365, with no detectable peptide loss or decrease in the fragmentation efficiency, although a progressive decrease in peptide intensity indicates that detection of low abundant proteins could not be optimal after very long periods of time. Our results encourage us to use the biobank facility in the future for long-term storage - up to 3 months - of dried peptide extracts.

Identifying genomic variant associated with long QT syndrome type 2 in an ecuadorian mestizo individual: a case report.

Introduction: Long QT syndrome (LQTS) is an autosomal dominant inherited cardiac condition characterized by a QT interval prolongation and risk of sudden death. There are 17 subtypes of this syndrome associated with genetic variants in 11 genes. The second most common is type 2, caused by a mutation in the KCNH2 gene, which is part of the potassium channel and influences the final repolarization of the ventricular action potential. This case report presents an Ecuadorian teen with congenital Long QT Syndrome type 2 (OMIM ID: 613688), from a family without cardiac diseases or sudden cardiac death backgrounds. Case presentation: A 14-year-old girl with syncope, normal echocardiogram, and an irregular electrocardiogram was diagnosed with LQTS. Moreover, by performing Next-Generation Sequencing, a pathogenic variant in the KCNH2 gene p.(Ala614Val) (ClinVar ID: VCV000029777.14) associated with LQTS type 2, and two variants of uncertain significance in the AKAP9 p.(Arg1654GlyfsTer23) (rs779447911), and TTN p. (Arg34653Cys) (ClinVar ID: VCV001475968.4) genes were identified. Furthermore, ancestry analysis showed a mainly Native American proportion. Conclusion: Based on the genomic results, the patient was identified to have a high-risk profile, and an implantable cardioverter defibrillator was selected as the best treatment option, highlighting the importance of including both the clinical and genomics aspects for an integral diagnosis.

Reduced mitochondrial pyruvate carrier expression in hearts with heart failure and reduced ejection fraction patients: ischemic vs. non-ischemic origin.

Introduction and objectives: Mitochondrial pyruvate carrier (MPC) mediates the entry of pyruvate into mitochondria, determining whether pyruvate is incorporated into the Krebs cycle or metabolized in the cytosol. In heart failure (HF), a large amount of pyruvate is metabolized to lactate in the cytosol rather than being oxidized inside the mitochondria. Thus, MPC activity or expression might play a key role in the fate of pyruvate during HF. The purpose of this work was to study the levels of the two subunits of this carrier, named MPC1 and MPC2, in human hearts with HF of different etiologies. Methods: Protein and mRNA expression analyses were conducted in cardiac tissues from three donor groups: patients with HF with reduced ejection fraction (HFrEF) with ischemic cardiomyopathy (ICM) or idiopathic dilated cardiomyopathy (IDC), and donors without cardiac pathology (Control). MPC2 plasma levels were determined by ELISA. Results: Significant reductions in the levels of MPC1, MPC2, and Sirtuin 3 (SIRT3) were observed in ICM patients compared with the levels in the Control group. However, no statistically significant differences were revealed in the analysis of MPC1 and MPC2 gene expression among the groups. Interestingly, Pyruvate dehydrogenase complex (PDH) subunits expression were increased in the ICM patients. In the case of IDC patients, a significant decrease in MPC1 was observed only when compared with the Control group. Notably, plasma MPC2 levels were found to be elevated in both disease groups compared with that in the Control group. Conclusion: Decreases in MPC1 and/or MPC2 levels were detected in the cardiac tissues of HFrEF patients, with ischemic or idiopatic origen, indicating a potential reduction in mitochondrial pyruvate uptake in the heart, which could be linked to unfavorable clinical features.

Proteomics analysis of cardiac extracellular matrix remodeling in a porcine model of ischemia/reperfusion injury.

BACKGROUND: After myocardial ischemia, extracellular matrix (ECM) deposition occurs at the site of the focal injury and at the border region. METHODS AND RESULTS: We have applied a novel proteomic method for the analysis of ECM in cardiovascular tissues to a porcine model of ischemia/reperfusion injury. ECM proteins were sequentially extracted and identified by liquid chromatography tandem mass spectrometry. For the first time, ECM proteins such as cartilage intermediate layer protein 1, matrilin-4, extracellular adipocyte enhancer binding protein 1, collagen α-1(XIV), and several members of the small leucine-rich proteoglycan family, including asporin and prolargin, were shown to contribute to cardiac remodeling. A comparison in 2 distinct cardiac regions (the focal injury in the left ventricle and the border region close to the occluded coronary artery) revealed a discordant regulation of protein and mRNA levels; although gene expression for selected ECM proteins was similar in both regions, the corresponding protein levels were much higher in the focal lesion. Further analysis based on >100 ECM proteins delineated a signature of early- and late-stage cardiac remodeling with transforming growth factor-ß1 signaling at the center of the interaction network. Finally, novel cardiac ECM proteins identified by proteomics were validated in human left ventricular tissue acquired from ischemic cardiomyopathy patients at cardiac transplantation. CONCLUSION: Our findings reveal a biosignature of early- and late-stage ECM remodeling after myocardial ischemia/reperfusion injury, which may have clinical utility as a prognostic marker and modifiable target for drug discovery.

Associations of MYPN, TTN, SCN5A, MYO6 and ELN Mutations With Arrhythmias and Subsequent Sudden Cardiac Death: A Case Report of an Ecuadorian Individual.

Cardiac pathologies are among the most frequent causes of death worldwide. Regarding cardiovascular deaths, it is estimated that 5 million cases are caused by sudden cardiac death (SCD) annually. The primary cause of SCD is ventricular arrhythmias. Genomic studies have provided pathogenic, likely pathogenic, and variants of uncertain significance that may predispose individuals to cardiac causes of sudden death. In this study, we describe the case of a 43-year-old individual who experienced an episode of aborted SCD. An implantable cardioverter defibrillator was placed to prevent further SCD episodes. The diagnosis was ventricular fibrillation. Genomic analysis revealed some variants in the MYPN (pathogenic), GCKR (likely pathogenic), TTN (variant of uncertain significance), SCN5A (variant of uncertain significance), MYO6 (variant of uncertain significance), and ELN (variant of uncertain significance) genes, which could be associated with SCD episodes. In addition, a protein-protein interaction network was obtained, with proteins related to ventricular arrhythmia and the biological processes involved. Therefore, this study identified genetic variants that may be associated with and trigger SCD in the individual. Moreover, genetic variants of uncertain significance, which have not been reported, could contribute to the genetic basis of the disease.

Genetic diet interactions of ACE: the increased hypertension predisposition in the Latin American population.

Hypertension is one of the primary risk factors associated with cardiovascular diseases (CVDs). It is a condition that affects people worldwide, and its prevalence is increasing due to several factors, such as lack of physical activity, population aging, and unhealthy diets. Notably, this increase has primarily occurred in low and middle-income countries (LMICs). In Latin America, approximately 40% of adults have been diagnosed with hypertension. Moreover, reports have shown that the Latin American genetic composition is highly diverse, and this genetic background can influence various biological processes, including disease predisposition and treatment effectiveness. Research has shown that Western dietary patterns, which include increased consumption of red meat, refined grains, sugar, and ultra-processed food, have spread across the globe, including Latin America, due to globalization processes. Furthermore, a higher than recommended sodium consumption, which has been associated with hypertension, has been identified across different regions, including Asia, Europe, America, Oceania, and Africa. In conclusion, hypertension is a multifactorial disease involving environmental and genetic factors. In Latin America, hypertension prevalence is increasing due to various factors, including age, the adoption of a "Westernized" diet, and potential genetic predisposition factors involving the ACE gene. Furthermore, identifying the genetic and molecular mechanisms of the disease, its association with diet, and how they interact is essential for the development of personalized treatments to increase its efficacy and reduce side effects.

Identification of mutations on the EMD and EYA4 genes associated with Emery-Dreifuss muscular dystrophy and deafness: a case report.

Introduction: Hearing loss is the most common sensory disability, and it is estimated that 50% of cases are caused by genetic factors. One of the genes associated with deafness is the eyes absent homolog 4 (EYA4) gene, a transcription factor related to the development and function of the inner ear. Emery-Dreifuss muscular dystrophy is a rare inherited disease characterized by atrophy and weakness of the humeroperoneal muscles, multi-joint contractures, and cardiac manifestations. It is inherited in an autosomal-dominant, X-linked, or less frequently autosomal recessive manner; one of the genes associated with EDMD is the emerin (EMD) gene. Case description: A total of two Ecuadorian siblings aged 57 (Subject A) and 55 (Subject B) were diagnosed with deafness and an unspecified type of muscular dystrophy based on family history and clinical findings. Next-generation sequencing (NGS) using the TruSight Cardio and Inherited Disease kits at the Centro de Investigación Genética y Genómica CIGG, Universidad UTE, was performed. The genetic analyses showed two mutations: a stop mutation in exon 11/20 (NM_004100.4:c.940G>T) of the EYA4 gene and a missense mutation in exon 6 (NM_000117.2:c.548C>G) of the EMD gene. Discussion and conclusion: The in silico predictions described the EYA4 variant as likely pathogenic and the EMD variant as a variant of uncertain significance (VUS). Moreover, an ancestry analysis was performed using 46 Ancestry Informative Insertion/Deletion Markers (AIM-InDels), and the ancestral composition of subject A was 46% African, 26.1% European, and 27.9% American Indian ancestry, whereas the ancestral composition of subject B was 41.3% African, 38.2% European, and 20.5% American Indian ancestry. The present case report describes two Ecuadorian siblings with a mainly African ancestral component, muscular dystrophy, and deafness phenotypes. Moreover, using next-generation sequencing (NGS), a mutation in the EMD and a novel mutation in EYA4 genes possibly associated with the subjects' phenotype were identified and discussed.

Genomic analysis of a novel pathogenic variant in the gene LMNA associated with cardiac laminopathies found in Ecuadorian siblings: A case report.

Introduction: Cardiac laminopathies are caused by mutations in the LMNA gene and include a wide range of clinical manifestations involving electrical and mechanical changes in cardiomyocytes. In Ecuador, cardiovascular diseases were the primary cause of death in 2019, accounting for 26.5% of total deaths. Cardiac laminopathy-associated mutations involve genes coding for structural proteins with functions related to heart development and physiology. Family description: Two Ecuadorian siblings, self-identified as mestizos, were diagnosed with cardiac laminopathies and suffered embolic strokes. Moreover, by performing Next-Generation Sequencing, a pathogenic variant (NM_170707.3:c.1526del) was found in the gene LMNA. Discussion and conclusion: Currently, genetic tests are an essential step for disease genetic counseling, including cardiovascular disease diagnosis. Identification of a genetic cause that may explain the risk of cardiac laminopathies in a family can help the post-test counseling and recommendations from the cardiologist. In the present report, a pathogenic variant ((NM_170707.3:c.1526del) has been identified in two Ecuadorian siblings with cardiac laminopathies. The LMNA gene codes for A-type laminar proteins that are associated with gene transcription regulation. Mutations in the LMNA gene cause laminopathies, disorders with diverse phenotypic manifestations. Moreover, understanding the molecular biology of the disease-causing mutations is essential in deciding the correct type of treatment.

The Autosomal Short Tandem Repeat Polymorphisms Are Potentially Associated with Cardiovascular Disease Predisposition in the Latin American Population: A Mini Review.

According to the World Health Organization, cardiovascular diseases (CVDs) are the leading cause of death worldwide across nearly all ethnic groups. Inherited cardiac conditions comprise a wide spectrum of diseases that affect the heart, including abnormal structural features and functional impairments. In Latin America, CVDs are the leading cause of death within the region. Factors such as population aging, unhealthy diet, obesity, smoking, and a sedentary lifestyle have increased the risk of CVD. The Latin American population is characterized by its diverse ethnic composition with varying percentages of each ancestral component (African, European, and Native American ancestry). Short tandem repeats (STRs) are DNA sequences with 2-6 base pair repetitions and constitute ~3% of the human genome. Importantly, significant allele frequency variations exist between different populations. While studies have described that STRs are in noncoding regions of the DNA, increasing evidence suggests that simple sequence repeat variations may be critical for proper gene activity and regulation. Furthermore, several STRs have been identified as potential disease predisposition markers. The present review is aimed at comparing and describing the frequencies of autosomal STR polymorphisms potentially associated with cardiovascular disease predisposition in Latin America compared with other populations.

Case report: Genomic screening for inherited cardiac conditions in Ecuadorian mestizo relatives: Improving familial diagnose.

Introduction: Genomic screening is an informative and helpful tool for the clinical management of inherited conditions such as cardiac diseases. Cardiac-inherited diseases are a group of disorders affecting the heart, its system, function, and vasculature. Among the cardiac inherited abnormalities, one of the most common is Wolff-Parkinson-White syndrome. Similarly, hypertrophic cardiomyopathy is another common autosomal dominant inherited cardiac disease. Hypertrophic cardiomyopathy is associated with an increased incidence of Wolff-Parkinson-White syndrome; reports have suggested that it could be caused by a mutation in the protein-coding gene PRKAG2, which encodes a subunit of the AMP-activated protein kinase. Case presentation: A 37-year-old Ecuadorian male (Subject A) with familiar history of bradycardia, cardiac pacemaker implantation, and undiagnosed cardiac conditions began with episodes of tachycardia, dizziness, shortness of breath, and a feeling of fainting. He was diagnosed with hypertrophic myocardiopathy and Wolff Parkinson White preexcitation syndrome. Furthermore, his cousin's son, an 18-year-old Ecuadorian male (Subject B), started suffering from migraine and tachycardia at any time of the day. He was diagnosed with hypertrophic myocardiopathy; his electrocardiogram showed a systolic overload. Next-generation sequencing and ancestry analyses were performed. A c.905G>A p.(Arg302Gln) mutation in the gene PRKAG2 and a mainly European composition were identified in both subjects. Conclusion: Genetic testing is a valuable tool as it can provide important information regarding a disease, including its cause and consequences, not only for single individuals but to identify at-risk relatives. Furthermore, NGS results could guide the physician into targeted therapy. In the present case report, a missense pathogenic Arg302Gln mutation in the PRKAG2 gene has been identified in two related Ecuadorian Subjects diagnosed with hypertrophic myocardiopathy and Wolff-Parkinson-White. The variant has not been reported in Latin America; hence, this is the first report of the Arg302Gln mutation in the PRKAG2 gene in mestizo Ecuadorian subjects with mainly European ancestry components.

Cardiac protection induced by urocortin-2 enables the regulation of apoptosis and fibrosis after ischemia and reperfusion involving miR-29a modulation.

Urocortin-2 (Ucn-2) has demonstrated cardioprotective actions against myocardial ischemia-reperfusion (I/R) injuries. Herein, we explored the protective role of Ucn-2 through microRNAs (miRNAs) post-transcriptional regulation of apoptotic and pro-fibrotic genes. We determined that the intravenous administration of Ucn-2 before heart reperfusion in a Wistar rat model of I/R recovered cardiac contractility and decreased fibrosis, lactate dehydrogenase release, and apoptosis. The infusion of Ucn-2 also inhibited the upregulation of 6 miRNAs in revascularized heart. The in silico analysis indicated that miR-29a and miR-451_1∗ are predicted to target many apoptotic and fibrotic genes. Accordingly, the transfection of neonatal rat ventricular myocytes with mimics overexpressing miR-29a, but not miR-451_1∗, prevented I/R-induced expression of pro- and anti-apoptotic genes such as Apaf-1, Hmox-1, and Cycs, as well as pro-fibrotic genes Col-I and Col-III. We also confirmed that Hmox-1, target of miR-29a, is highly expressed at the mRNA and protein levels in adult rat heart under I/R, whereas, Ucn-2 abolished I/R-induced mRNA and protein upregulation of HMOX-1. Interestingly, a significant upregulation of Hmox-1 was observed in the ventricle of ischemic patients with heart failure, correlating negatively with the left ventricle ejection fraction. Altogether, these data indicate that Ucn-2, through miR-29a regulation, provides long-lasting cardioprotection, involving the post-transcriptional regulation of apoptotic and fibrotic genes.

Specialized Proresolving Mediators Protect Against Experimental Autoimmune Myocarditis by Modulating Ca2+ Handling and NRF2 Activation.

Specialized proresolving mediators and, in particular, 5(S), (6)R, 7-trihydroxyheptanoic acid methyl ester (BML-111) emerge as new therapeutic tools to prevent cardiac dysfunction and deleterious cardiac damage associated with myocarditis progression. The cardioprotective role of BML-111 is mainly caused by the prevention of increased oxidative stress and nuclear factor erythroid-derived 2-like 2 (NRF2) down-regulation induced by myocarditis. At the molecular level, BML-111 activates NRF2 signaling, which prevents sarcoplasmic reticulum-adenosine triphosphatase 2A down-regulation and Ca2+ mishandling, and attenuates the cardiac dysfunction and tissue damage induced by myocarditis.

Gene expression profiles following intracoronary injection of mesenchymal stromal cells using a porcine model of chronic myocardial infarction.

BACKGROUND AIMS: We evaluated the therapeutic potential of injection of in vitro differentiated bone marrow mesenchymal stromal cells (MSC) using a swine model. METHODS AND RESULTS: Myocardial infarction was induced by coronary occlusion. Three groups (n = 5 each) were analyzed: one group received an injection of 17.8 ± 9.3 × 10(6) 5-azacytidine-treated allogeneic MSC 1 month after infarction; a placebo group received an injection of medium; and controls were kept untreated. After 4 weeks, heart samples were taken from three infarcted areas, interventricular septa, ventricles and atria. Gene expression profiles of genes related to contractility (Serca2a), fibrosis (Col1a1), cardiomyogenesis (Mef2c, Gata4 and Nkx2.5) and mobilization of stem cells (Sdf1, Cxcr4 and c-kit) were compared by quantitative real-time PCR (qRT-PCR). Gene expression profiles varied in different heart areas. Thus Serca2a expression was reduced in infarcted groups in all heart regions except for the left ventricles, where Col1a1 was overexpressed. The expression of genes related to cardiomyogenesis decreased in the infarcted zones and left atria compared with healthy hearts. Interestingly, increased expression of Cxcr4 was detected in infarcted regions of MSC-treated pigs compared with the placebo group. CONCLUSIONS: Infarction induced changes in expression of genes involved in various biologic processes. Genes involved in cardiomyogenesis were downregulated in the left atrium. The intracoronary injection of MSC resulted in localized changes in the expression of Cxcr4.