Unique pediatric penetrating cardiac trauma caused by a palm tree frond: Case report.

Mortality rates are significantly affected by severe cardiac trauma in both adult and pediatric patients. Although rare in children, cardiac injuries of significant magnitude can lead to fatal outcomes. We report the rare case of a 5-year-old girl who sustained a penetrating cardiac injury from a sharp palm tree frond in a home accident. Immediately, the patient was transferred to a tertiary care center, and life-saving measures were initiated. To ensure prompt optimal care, the pediatric emergency medicine team leader delegated team tasks 1 hour before arrival. The patient underwent immediate surgical repair and experienced a smooth recovery with appropriate management.

Cardioprotection of voluntary exercise against breast cancer-induced cardiac injury via STAT3.

Exercise is an effective way to alleviate breast cancer-induced cardiac injury to a certain extent. However, whether voluntary exercise (VE) activates cardiac signal transducer and activator of transcription 3 (STAT3) and the underlying mechanisms remain unclear. This study investigated the role of STAT3-microRNA(miRNA)-targeted protein axis in VE against breast cancer-induced cardiac injury.VE for 4 weeks not only improved cardiac function of transgenic breast cancer female mice [mouse mammary tumor virus-polyomavirus middle T antigen (MMTV-PyMT +)] compared with littermate mice with no cancer (MMTV-PyMT -), but also increased myocardial STAT3 tyrosine 705 phosphorylation. Significantly more obvious cardiac fibrosis, smaller cardiomyocyte size, lower cell viability, and higher serum tumor necrosis factor (TNF)-α were shown in MMTV-PyMT + mice compared with MMTV-PyMT - mice, which were ameliorated by VE. However, VE did not influence the tumor growth. MiRNA sequencing identified that miR-181a-5p was upregulated and miR-130b-3p was downregulated in VE induced-cardioprotection. Myocardial injection of Adeno-associated virus serotype 9 driving STAT3 tyrosine 705 mutations abolished cardioprotective effects above. Myocardial STAT3 was identified as the transcription factor binding the promoters of pri-miR-181a (the precursor of miR-181a-5p) and HOX transcript antisense RNA (HOTAIR, sponged miR-130b-3p) in isolated cardiomyocytes. Furthermore, miR-181a-5p targeting PTEN and miR-130b-3p targeting Zinc finger and BTB domain containing protein 20 (Zbtb20) were proved in AC-16 cells. These findings indicated that VE protects against breast cancer-induced cardiac injury via activating STAT3 to promote miR-181a-5p targeting PTEN and to promote HOTAIR to sponge miR-130b-3p targeting Zbtb20, helping to develop new targets in exercise therapy for breast cancer-induced cardiac injury.

Association between global longitudinal strain and occurrence of cardiovascular events among pediatric patients following high-dose cyclophosphamide chemotherapy: a prospective cohort study.

Background: The fatal cyclophosphamide cardiotoxicity is associated with high mortality in the adult population, and the study of its effects on children represents a gap in the field. This study aimed to evaluate the potential of global longitudinal strain (GLS) as a predictor of cardiovascular events among children with high-dose cyclophosphamide chemotherapy. Methods: This was a prospective cohort study of patients aged 14 years or younger who received high-dose (>120 mg/kg) cyclophosphamide chemotherapy recruited consecutively. Blood collection and echocardiography were performed 1 day before and after cyclophosphamide chemotherapy, and patients were followed up for 30 days with echocardiography. GLS and other echocardiography indicators were calculated accordingly. The primary outcome was the occurrence of cardiovascular events within 30 days after cyclophosphamide chemotherapy. The association between GLS and outcome was analyzed by using univariate and multivariable-adjusted Poisson regression. Results: A total of 29 subjects were included. Among them, 10 patients (34.48%) developed cardiovascular events during a median follow-up of 10 (interquartile range, 5-13) days. Although similar before cyclophosphamide chemotherapy, GLS 1 day after cyclophosphamide chemotherapy was significantly lower in the cardiac injury group than in the noncardiac injury group (-18.33%±1.81% vs. -20.03%±1.49%, P=0.01). In the multivariable analysis adjusted for total cyclophosphamide dose (160 vs. 120-159 mg/kg) and global circumferential strain, GLS remained an independent predictor for cardiovascular events [incidence rate ratio: 1.46, 95% confidence interval: 1.02-2.09, P=0.04]. Conclusions: GLS after cyclophosphamide chemotherapy may be a reliable indicator to predict cardiovascular events in patients receiving cyclophosphamide chemotherapy, which might be essential in optimizing treatment strategies for this high-risk patient group.

Resuscitation and Forensic Factors Influencing Outcome in Penetrating Cardiac Injury.

BACKGROUND: Cardiac injury caused by a sharp object is a medical and surgical therapeutic challenge. Mortality risk factors have been identified but there are major discrepancies in the literature. The aim of this study was to analyse the management of victims of penetrating cardiac injuries before and after admission to hospital and the anatomical characteristics of these injuries in order to facilitate diagnosis of the most critical patients. METHODS: To carry out this study, we conducted a retrospective analytical study with epidemiological data on victims of penetrating cardiac injuries. We included two types of patients, with those who underwent autopsy in our institution after death from sharp injury to the heart or great vessels and those who survived with treatment in the emergency department or intensive care unit between January 2015 and February 2022. RESULTS: We included 30 autopsied patients and 12 survivors aged between 18 and 73 years. Higher mortality was associated with prehospital or in-hospital cardiorespiratory arrest (OR = 4, CI [1.71-9.35]), preoperative mechanical ventilation (OR = 10, CI [1.53-65.41]), preoperative catecholamines (OR = 7, CI [1.12-6.29]), preoperative and perioperative adrenaline (OR = 13, CI [1.98-85.46] and [1.98-85.46]), penetrating cardiac injury (OR = 14, CI [2.10-93.22]), multiple cardiac injuries (OR = 1.5, CI [1.05-2.22]) and an Organ Injury Scaling of the American Association for the Surgery of Trauma (AAST-OIS) score of 5 (OR = 2.9, CI [1.04-8.54]; p = 0.0329) with an AUC-ROC curve value of 0.708 (CI [0.543-0.841]). CONCLUSIONS: This study identified risk mortality factors in penetrating cardiac injury patients. These findings can help improve the diagnosis and management of these patients. The AAST-OIS score may be a good tool to diagnose critical patients.

SiO 2 Induces Iron Overload and Ferroptosis in Cardiomyocytes in a Silicosis Mouse Model.

Objective: The aim of this study was to explore the role and mechanism of ferroptosis in SiO 2-induced cardiac injury using a mouse model. Methods: Male C57BL/6 mice were intratracheally instilled with SiO 2 to create a silicosis model. Ferrostatin-1 (Fer-1) and deferoxamine (DFO) were used to suppress ferroptosis. Serum biomarkers, oxidative stress markers, histopathology, iron content, and the expression of ferroptosis-related proteins were assessed. Results: SiO 2 altered serum cardiac injury biomarkers, oxidative stress, iron accumulation, and ferroptosis markers in myocardial tissue. Fer-1 and DFO reduced lipid peroxidation and iron overload, and alleviated SiO 2-induced mitochondrial damage and myocardial injury. SiO 2 inhibited Nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes, while Fer-1 more potently reactivated Nrf2 compared to DFO. Conclusion: Iron overload-induced ferroptosis contributes to SiO 2-induced cardiac injury. Targeting ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO 2 cardiotoxicity, potentially via modulation of the Nrf2 pathway.

In vivo proximity proteomics uncovers palmdelphin (PALMD) as a Z-disc-associated mitigator of isoproterenol-induced cardiac injury.

Z-discs are core ultrastructural organizers of cardiomyocytes that modulate many facets of cardiac pathogenesis. Yet a comprehensive proteomic atlas of Z-disc-associated components remain incomplete. Here, we established an adeno-associated virus (AAV)-delivered, cardiomyocyte-specific, proximity-labeling approach to characterize the Z-disc proteome in vivo. We found palmdelphin (PALMD) as a novel Z-disc-associated protein in both adult murine cardiomyocytes and human pluripotent stem cell-derived cardiomyocytes. Germline and cardiomyocyte-specific Palmd knockout mice were grossly normal at baseline but exhibited compromised cardiac hypertrophy and aggravated cardiac injury upon long-term isoproterenol treatment. By contrast, cardiomyocyte-specific PALMD overexpression was sufficient to mitigate isoproterenol-induced cardiac injury. PALMD ablation perturbed the transverse tubule (T-tubule)-sarcoplasmic reticulum (SR) ultrastructures, which formed the Z-disc-associated junctional membrane complex (JMC) essential for calcium handling and cardiac function. These phenotypes were associated with the reduction of nexilin (NEXN), a crucial Z-disc-associated protein that is essential for both Z-disc and JMC structures and functions. PALMD interacted with NEXN and enhanced its protein stability while the Nexn mRNA level was not affected. AAV-based NEXN addback rescued the exacerbated cardiac injury in isoproterenol-treated PALMD-depleted mice. Together, this study discovered PALMD as a potential target for myocardial protection and highlighted in vivo proximity proteomics as a powerful approach to nominate novel players regulating cardiac pathogenesis.

Association of Blood Metals and Metal Mixtures with the Myocardial Enzyme Profile: An Occupational Population-Based Study in China.

To investigate a cross-sectional association between blood metal mixture and myocardial enzyme profile, we quantified creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LD), α-hydroxybutyrate dehydrogenase (α-HBD), and aspartate transaminase (AST) levels among participants from the manganese-exposed workers healthy cohort (MEWHC) (n = 544). The levels of 22 metals in blood cells were determined using inductively coupled plasma mass spectrometry. The least absolute shrinkage and selection operator (LASSO) penalized regression model was utilized for screening metals. The exposure-response relationship between specific metal and myocardial enzyme profile was identified by general linear regression and restricted cubic spline analyses. The overall effect and interactions were evaluated using Bayesian kernel machine regression (BKMR). Manganese was linearly and positively associated with CK (Poverall = 0.019, Pnon-linearity = 0.307), dominating the positive overall effect of mixture exposure (manganese, arsenic, and rubidium) on CK level. Calcium and zinc were linearly and negatively associated with LD levels (Poverall < 0.05, Pnon-linearity > 0.05), and asserted dominance in the negative overall effect of metal mixtures (rubidium, molybdenum, zinc, nickel, cobalt, calcium, and magnesium) on LD level. Interestingly, we observed a U-shaped dose-response relationship of molybdenum with LD level (Poverall < 0.001, Pnon-linearity = 0.015), an interaction between age and calcium on LD level (Pinteration = 0.041), and an interaction between smoking and molybdenum on LD level (Pinteration = 0.035). Our study provides evidence that metal mixture exposure affects the myocardial enzyme profile. Additional investigation is required to confirm these associations, and to reveal the fundamental mechanisms involved.

The Potential Mechanisms Behind Adverse Effect of Coronavirus Disease-19 on Heart and Liver Damage: A Review.

Background: Coronaviruses (CoVs) belong to the RNA viruses family. The viruses in this family are known to cause mild respiratory disease in humans. The origin of the novel SARS-COV2 virus that caused the coronavirus-19 disease (COVID-19) is the Wuhan city in China from where it disseminated to cause a global pandemic. Although lungs are the predominant target organ for Coronavirus Disease-19 (COVID-19), since its outbreak, the disease is known to affect heart, blood vessels, kidney, intestine, liver and brain. This review aimed to summarize the catastrophic impacts of Coronavirus disease-19 on heart and liver along with its mechanisms of pathogenesis. Methods: The information used in this review was obtained from relevant articles published on PubMed, Google Scholar, Google, WHO website, CDC and other sources. Key searching statements and phrases related to COVID-19 were used to retrieve information. Original research articles, review papers, research letters and case reports were used as a source of information. Results: Besides causing severe lung injury, COVID-19 has also been reported to affect and cause dysfunction of many other organs. COVID-19 infection can affect people by downregulating membrane-bound active angiotensin-converting enzyme (ACE). People who have deficient ACE2 expression are more vulnerable to COVID-19 infection. The patients' pre-existing co-morbidities are major risk factors that predispose individuals to severe COVID-19. Conclusion: The disease severity and its broad spectrum phenotype is a result of combined direct and indirect pathogenic factors. Therefore, protocols that harmonize many therapeutic preferences should be the best alternatives to de-escalate the disease and obviate deaths caused as a result of multiple organ damage and dysfunction induced by the disease.

Bazi Bushen capsule attenuates cardiac systolic injury via SIRT3/SOD2 pathway in high-fat diet-fed ovariectomized mice.

Background: Bazi Bushen capsule (BZBS) is a Chinese herbal compound that is clinically used to treat fatigue and forgetfulness. However, it is still unclear whether and how BZBS affects heart function decline in menopausal women. This study aimed to examine the effect of BZBS on cardiac function in a high-fat diet-fed ovariectomy (HFD-fed OVX) mouse model and elucidate the underlying mechanism of this effect. Methods: The experimental animals were divided into five groups: sham group, HFD-fed OVX group, and BZBS (0.7, 1.4, 2.8 g/kg) intervention groups. Senescence ß-galactosidase staining and echocardiography were used to evaluate cardiac function. SwissTargetPrediction, KEGG and GO enrichment analyses were used to screen the underlying mechanism of BZBS. The morphological and functional changes in cardiac mitochondria and the underlying molecular mechanism were assessed by transmission electron microscopy, western blotting and biochemical assays. STRING database was used to analysis protein-protein interaction (PPI) network. Molecular docking studies were employed to predict the interactions of specific BZBS compounds with their protein targets. Results: BZBS treatment ameliorated cardiac senescence and cardiac systole injury in HFD-fed OVX mice. GO and KEGG analyses revealed that the 530 targets of the 14 main components of BZBS were enriched mainly in the oxidative stress-associated pathway, which was confirmed by the finding that BZBS treatment prevented abnormal morphological changes and oxidative stress damage to cardiac mitochondria in HFD-fed OVX mice. Furthermore, the STRING database showed that the targets of BZBS were broadly related to the Sirtuins family. And BZBS upregulated the SIRT3 and elevated the activity of SOD2 in the hearts of HFD-fed OVX mice, which was also verified in vitro. Additionally, we revealed that imperatorin and osthole from the BZBS upregulated the expression of SIRT3 by directly docking with the transcription factors HDAC1, HDAC2, and BRD4, which regulate the expression of SIRT3. Conclusion: This research shows that the antioxidative effect and cardioprotective role of BZBS on HFD-fed OVX mice involves an increase in the activity of the SIRT3/SOD2 pathway, and the imperatorin and osthole of BZBS may play central roles in this process.

Vaccarin alleviates septic cardiomyopathy by potentiating NLRP3 palmitoylation and inactivation.

BACKGROUND: Sepsis often leads to significant morbidity and mortality due to severe myocardial injury. As is known, the activation of NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome crucially contributes to septic cardiomyopathy (SCM) by facilitating the secretion of interleukin (IL)-1ß and IL-18. The removal of palmitoyl groups from NLRP3 is a crucial step in the activation of the NLRP3 inflammasome. Thus, the potential inhibitors that regulate the palmitoylation and inactivation of NLRP3 may significantly diminish sepsis-induced cardiac dysfunction. PURPOSE: The present study sought to explore the effects of the prospective flavonoid compounds targeting NLRP3 on SCM and to elucidate the associated underlying mechanisms. STUDY DESIGN: The palmitoylation and activation of NLRP3 were detected in H9c2 cells and C57BL/6 J mice. METHODS/RESULTS: Echocardiography, histological staining, western blotting, co-immunoprecipitation, qPCR, ELISA and network pharmacology were used to assess the impact of vaccarin (VAC) on SCM in mice subjected to lipopolysaccharide (LPS) injection. From the collection of 74 compounds, we identified that VAC had the strongest capability to suppress NLRP3 luciferase report gene activity in cardiomyocytes, and the anti-inflammatory characteristics of VAC were further ascertained by the network pharmacology. Exposure of LPS triggered apoptosis, inflammation, oxidative stress, mitochondrial disorder in cardiomyocytes. The detrimental alterations were significantly reversed upon VAC treatment in both septic mice and H9c2 cells exposed to LPS. In vivo experiments demonstrated that VAC treatment alleviated septic myocardial injury, indicated by enhanced cardiac function parameters, preserved cardiac structure, and reduced inflammation/oxidative response. Mechanistically, VAC induced NLRP3 palmitoylation to inactivate NLRP3 inflammasome by acting on zDHHC12. In support, the NLRP3 agonist ATP and the acylation inhibitor 2-bromopalmitate (2-BP) prevented the effects of VAC. CONCLUSION: Our findings suggest that VAC holds promise in protecting against SCM by mitigating cardiac oxidative stress and inflammation via priming NLRP3 palmitoylation and inactivation. These results lay the solid basis for further assessment of the therapeutic potential of VAC against SCM.

Re-evaluating the Use of High Sensitivity Troponin to Diagnose Blunt Cardiac Injury.

INTRODUCTION: Blunt cardiac injury (BCI) can be challenging diagnostically, and if misdiagnosed, can lead to life-threatening complications. Our institution previously evaluated BCI screening with troponin and electrocardiogram (EKG) during a transition from troponin I to high sensitivity troponin (hsTnI), a more sensitive troponin I assay. The previous study found an hsTnI of 76 ng/L had the highest capability of accurately diagnosing a clinically significant BCI. The aim of this study was to determine the efficacy of the newly implemented protocol. METHODS: Patients diagnosed with a sternal fracture from March 2022 to April 2023 at our urban level-1 trauma center were retrospectively reviewed for EKG findings, hsTnI trend, echocardiogram changes, and clinical outcomes. The BCI cohort and non-BCI cohort ordinal measures were compared using Wilcoxon's two-tailed rank sum test and categorical measures were compared with Fisher's exact test. Youden indices were used to evaluate hsTnI sensitivity and specificity. RESULTS: Sternal fractures were identified in 206 patients, of which 183 underwent BCI screening. Of those screened, 103 underwent echocardiogram, 28 were diagnosed with clinically significant BCIs, and 15 received intervention. The peak hsTnI threshold of 76 ng/L was found to have a Youden index of 0.31. Rather, the Youden index was highest at 0.50 at 40 ng/L (sensitivity 0.79 and specificity 0.71) for clinically significant BCI. CONCLUSIONS: Screening patients with sternal fractures for BCI using hsTnI and EKG remains effective. To optimize the hsTnI threshold, this study determined the hsTnI threshold should be lowered to 40 ng/L. Further improvements to the institutional protocol may be derived from multicenter analysis.

Needle Decompression Complicated by Cardiac Injury in a Prehospital Environment.

Needle decompression is a mainstay intervention for tension pneumothorax in trauma medicine. It is used in combat and prehospital medicine when definitive measures are often not available or ideal. It can temporarily relieve increased intrathoracic pressure and treat a collapsed lung or great vessel obstruction. However, when done incorrectly, it can result in underlying visceral organ and vessel trauma. This is a case of an adult male who presented to the emergency department after sustaining multiple stab wounds during an altercation. On arrival, the patient had a 14-gauge angiocatheter inserted at the 4th intercostal space (ICS), left of the parasternal line traversing the right ventricle and interventricular septum and terminating in the left ventricle. The case emphasizes the importance of understanding the landmarks of performing needle decompression in increasing the procedure's efficacy and reducing iatrogenic complications.

Knockdown of LncRNA Lcn2-204 alleviates sepsis-induced myocardial injury by regulation of iron overload and ferroptosis.

Ferroptosis is an iron-dependent programmed cell death form resulting from lipid peroxidation damage, it plays a key role in organ damage and tumor development from various causes. Sepsis leads to severe host response after infection with high mortality. The long non-coding RNAs (LncRNAs) are involved in different pathophysiological mechanisms of multiple diseases. Here, we used cecal ligation and puncture (CLP) operation to mimic sepsis induced myocardial injury (SIMI) in mouse model, and LncRNAs and mRNAs were profiled by Arraystar mouse LncRNA Array V3.0. Based on the microarray results, 552 LncRNAs and 520 mRNAs were differentially expressed in the sham and CLP groups, among them, LncRNA Lcn2-204 was the highest differentially expressed up-regulated LncRNA. Iron metabolism disorder was involved in SIMI by bioinformatics analysis, meanwhile, myocardial iron content and lipocalin-2 (Lcn2) protein expressions were increased. The CNC network comprised 137 positive interactions and 138 negative interactions. Bioinformatics analysis showed several iron-related terms were enriched and six genes (Scara5, Tfrc, Lcn2, Cp, Clic5, Ank1) were closely associated with iron metabolism. Then, we constructed knockdown LncRNA Lcn2-204 targeting myocardium and found that it ameliorated cardiac injury in mouse sepsis model through modulating iron overload and ferroptosis. In addition, we found that LncRNA Lcn2-204 was involved in the regulation of Lcn2 expression in septic myocardial injury. Based on these findings, we conclude that iron overload and ferroptosis are the key mechanisms leading to myocardial injury in sepsis, knockdown of LncRNA Lcn2-204 plays the cardioprotective effect through inhibition of iron overload, ferroptosis and Lcn2 expression. It may provide a novel therapeutic approach to ameliorate sepsis-induced myocardial injury.

Tirzepatide protects against doxorubicin-induced cardiotoxicity by inhibiting oxidative stress and inflammation via PI3K/Akt signaling.

BACKGROUND: Doxorubicin (DOX) is a highly effective and widely used cytotoxic agent with application for various malignancies, but it's clinically limited due to its cardiotoxicity Oxidative stress and inflammation were reported to take part in DOX-induced cardiotoxicity. Tirzepatide, a dual glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist has been approved to treat type 2 diabetes. However, its role in DOX-induced cardiotoxicity and the underlying mechanisms has not been explored. METHODS: The cardioprotective properties of Tirzepatide against DOX-induced cardiotoxicity are examined in this work both in vivo and in vitro. For four weeks, an intraperitoneal injection of 4 mg/kg DOX was used to cause cardiotoxicity in C57BL/6 mice. To ascertain the cardioprotective function and underlying mechanisms of Tirzepatide against DOX-induced cardiotoxicity, mice and H9c2 cells were treated with and without Tirzepatide. RESULTS: Tirzepatide treatment significantly inhibited DOX-induced oxidative stress, inflammation and cardiac injury. Mechanistically, PI3K/Akt signaling pathway contributes to the protective effect of Tirzepatide against DOX-induced cardiotoxicity and inhibited PI3K/Akt signaling pathway with LY294002 almost blocked its therapeutic effect. CONCLUSIONS: Collectively, Tirzepatide could alleviate DOX-induced oxidative stress, inflammation and cardiac injury via activating PI3K/Akt signaling pathway and Tirzepatide may be a novel therapeutic target for DOX-induced cardiotoxicity.

Fetal cardiac troponin I levels decline toward birth in sheep.

Elevated cardiac troponin I (cTnI), a myocardial damage biomarker, has been reported in cord blood of neonates delivered vaginally or by cesarean section. Although the neonatal peak likely reflects the physiological adjustment to extrauterine life, a better understanding of serial prepartum changes is required to determine physiological causes of fetal cTnI release. We longitudinally sampled eight healthy lambs (20 days before spontaneous birth to 5 days postnatal), and from three fetuses receiving intravenous IGF-1. Samples were collected into heparin, and the plasma was stored at -80°C for later determination of high-sensitivity (hs) cTnI levels (BeckmanCoulter UniCel DxI Access IA; log transformed detection limit = 0.30, quantification limit = 0.78, 99th percentile = 1.78). Positive and negative control samples were drawn from an adult ewe during a terminal experiment (myocardial ischemia) and similarly assessed. hs-cTnI data were log transformed from ng/L. Log(hs-cTnI) was 1.47 ± 0.30 (means ± SD) at 20 days before birth and declined to 1.02 ± 0.65 in fetuses 12 ± 4 h before birth (P < 0.0001, R2 = 0.7869). Birth stimulated a delayed, transient peak in hs-cTnI (P = 0.0058). Newborn (43 ± 19 min postnatal) levels were 1.39 ± 0.40 (P = 0.0650 vs. fetus on day of birth) and 2.14 ± 0.63 the day after birth (P = 0.0331 vs. newborn). The second day after birth, levels declined to 1.65 ± 0.48 (P = 0.0238 vs. day 1). IGF-1 infusion increased hs-cTnI levels 25-50% over baseline (P = 0.0252, R2 = 0.9938). Baseline adult ewe log(hs-cTnI) was below the limit of detection; 3 h following coronary artery ligation, levels were 3.21. In conclusion, we newly report that fetal hs-cTnI levels decline concomitantly with reduced proliferation of cardiomyocytes toward term.NEW & NOTEWORTHY Serial blood samples were collected from catheterized, normally developing fetal and newborn lambs and high-sensitivity cardiac troponin I (hs-cTnI) levels were assessed, providing unprecedented insight into the physiological processes leading to high levels in the perinatal period. Moderately high levels of hs-cTnI found in the normally developing fetus declined toward term. An elevation to high levels peaked the day after birth, after which hs-cTnI declined again. Stimulation of fetal cardiomyocyte proliferation with IGF-1 also elevated hs-cTnI.

Glycyrrhizin Ameliorates Cardiac Injury in Rats with Severe Acute Pancreatitis by Inhibiting Ferroptosis via the Keap1/Nrf2/HO-1 Pathway.

BACKGROUND: Severe acute pancreatitis (SAP) is a potential fatal gastrointestinal disease that is usually complicated by myocardial injury and dysfunction. Due to the lack of understanding of the mechanism of SAP-associated cardiac injury (SACI), there is still no complete treatment. AIMS: To explore the alleviative effect and anti-ferroptosis mechanism against SACI of glycyrrhizin (GL), an inhibitor of oxidative stress. METHODS: The SAP model was established by perfusing 5% sodium taurocholate into biliopancreatic duct in rats. H&E staining and serum assays were used to assess the injury changes of pancreas and heart. Echocardiography was used to evaluate the cardiac function. Transmission electron microscopy (TEM) and oxidative stress assays were used to investigate the ferroptosis-related morphological and biochemical changes. Western blot and immunofluorescence were performed to analyzed the expression of ferroptosis-related proteins. RESULTS: Significant myocardial impairment was found in SAP rats according to increased histopathological scores, serum creatine kinase-MB (CK-MB) and cardiac troponin-I (cTnI) levels, and a decreased fractional shortening and ejection fraction. The decreased mitochondrial cristae and significant expression changes of ferroptosis-related proteins confirmed the presence of ferroptosis in SACI. GL treatment attenuated above-mentioned cardiac tissues damage by inhibiting ferroptosis via restoring the expression of Nrf2 and HO-1 in vivo and in vitro. Treating with ML385 (a Nrf2 inhibitor) or transfecting with siRNA-Nrf2 reversed the protective effect of GL. CONCLUSIONS: Our findings demonstrate the involvement of ferroptosis in SACI and suggest a potential role for GL in the treatment of SACI by supressing ferroptosis via Keap1/Nrf2/HO-1 pathway.

From Blunt Cardiac Injury to Heart Transplant Following Motorcycle Collision.

Traumatic coronary artery occlusion and dissection is an exceedingly rare complication of blunt cardiac injury (BCI), though it has been previously noted in a number of case reports. However, it can also lead to heart transplant, which to our knowledge has not been previously described in the literature. We present a case of a healthy 24-year-old man without significant past medical history who was in a motorcycle accident, resulting in sternal fracture and BCI. He was ultimately found to have thrombotic occlusion and dissection of his left anterior descending artery (LAD), requiring mechanical thrombectomy and drug-eluting stent, as well as subsequent hospitalizations and operations due to various complications. It was suspected that he went into ventricular fibrillation and had a second motorcycle collision, resulting in cardiogenic shock. Ultimately, his progression of ischemic cardiomyopathy and mitral regurgitation led to the need for heart transplant. Blunt cardiac injury with myocardial contusion has such a broad range of pathologies. It is essential that patients with these injury patterns raise a high level of suspicion for BCI and are followed closely with appropriate diagnostic testing and rapid intervention for best possible outcomes.

Organ-Specific Mitochondrial Alterations Following Ischemia-Reperfusion Injury in Post-Cardiac Arrest Syndrome: A Comprehensive Review.

BACKGROUND: Mitochondrial dysfunction, which is triggered by systemic ischemia-reperfusion (IR) injury and affects various organs, is a key factor in the development of post-cardiac arrest syndrome (PCAS). Current research on PCAS primarily addresses generalized mitochondrial responses, resulting in a knowledge gap regarding organ-specific mitochondrial dynamics. This review focuses on the organ-specific mitochondrial responses to IR injury, particularly examining the brain, heart, and kidneys, to highlight potential therapeutic strategies targeting mitochondrial dysfunction to enhance outcomes post-IR injury. METHODS AND RESULTS: We conducted a narrative review examining recent advancements in mitochondrial research related to IR injury. Mitochondrial responses to IR injury exhibit considerable variation across different organ systems, influenced by unique mitochondrial structures, bioenergetics, and antioxidative capacities. Each organ demonstrates distinct mitochondrial behaviors that have evolved to fulfill specific metabolic and functional needs. For example, cerebral mitochondria display dynamic responses that can be both protective and detrimental to neuronal activity and function during ischemic events. Cardiac mitochondria show vulnerability to IR-induced oxidative stress, while renal mitochondria exhibit a unique pattern of fission and fusion, closely linked to their susceptibility to acute kidney injury. This organ-specific heterogeneity in mitochondrial responses requires the development of tailored interventions. Progress in mitochondrial medicine, especially in the realms of genomics and metabolomics, is paving the way for innovative strategies to combat mitochondrial dysfunction. Emerging techniques such as mitochondrial transplantation hold the potential to revolutionize the management of IR injury in resuscitation science. CONCLUSIONS: The investigation into organ-specific mitochondrial responses to IR injury is pivotal in the realm of resuscitation research, particularly within the context of PCAS. This nuanced understanding holds the promise of revolutionizing PCAS management, addressing the unique mitochondrial dysfunctions observed in critical organs affected by IR injury.

Rat Model of Isoproterenol-Induced Myocardial Injury.

Isoproterenol (ISO) administration produces significant biochemical and histological changes including oxidative stress, reactive oxygen species (ROS) overproduction, and inflammation that leads to aggravation of myocardial injury. Subcutaneous or intraperitoneal ISO injection into rats can replicate several features of human heart disease, making it a useful tool for comprehending the underlying mechanisms and evaluating potential therapeutic strategies. In the present chapter, we elaborate on how depending on the precise experimental goals and the intended level of severity, different dosages and regimens are employed to induce myocardial injury.

Mapping the interplay of immunoproteasome and autophagy in different heart failure phenotypes.

Proper protein degradation is required for cellular protein homeostasis and organ function. Particularly, in post-mitotic cells, such as cardiomyocytes, unbalanced proteolysis due to inflammatory stimuli and oxidative stress contributes to organ dysfunction. To ensure appropriate protein turnover, eukaryotic cells exert two main degradation systems, the ubiquitin-proteasome-system and the autophagy-lysosome-pathway. It has been shown that proteasome activity affects the development of cardiac dysfunction differently, depending on the type of heart failure. Studies analyzing the inducible subtype of the proteasome, the immunoproteasome (i20S), demonstrated that the i20S plays a double role in diseased hearts. While i20S subunits are increased in cardiac hypertrophy, atrial fibrillation and partly in myocarditis, the opposite applies to diabetic cardiomyopathy and ischemia/reperfusion injury. In addition, the i20S appears to play a role in autophagy modulation depending on heart failure phenotype. This review summarizes the current literature on the i20S in different heart failure phenotypes, emphasizing the two faces of i20S in injured hearts. A selection of established i20S inhibitors is introduced and signaling pathways linking the i20S to autophagy are highlighted. Mapping the interplay of the i20S and autophagy in different types of heart failure offers potential approaches for developing treatment strategies against heart failure.