Search Results (348)

Coronary microvascular obstruction and dysfunction (CMVO) frequently arise following primary percutaneous coronary intervention (PCI), particularly in individuals with myocardial infarction. Despite the restoration of epicardial blood flow, microvascular perfusion might still be compromised, resulting in negative clinical outcomes. CMVO is a complex condition resulting from a combination of ischemia, distal thrombotic embolization, reperfusion injury, and individual susceptibilities such as inflammation and endothelial dysfunction. The pathophysiological features of this condition include microvascular spasm, endothelial swelling, capillary plugging by leukocytes and platelets, and oxidative stress. Traditional angiographic assessments, such as Thrombolysis in Myocardial Infarction (TIMI) flow grade and myocardial blush grade, have limited sensitivity. Cardiac magnetic resonance imaging (CMR) stands as the gold standard for identifying CMVO, while the index of microvascular resistance (IMR) is a promising invasive option. Treatment approaches involve powerful antiplatelet drugs, anticoagulants, and supersaturated oxygen, yet no treatment has been definitively shown to reverse established CMVO. CMVO remains a significant therapeutic challenge in coronary artery disease management. Enhancing the comprehension of its core mechanisms is vital for the development of more effective and personalized treatment strategies. Full article

Cardiovascular diseases remain the leading cause of death worldwide, highlighting the urgent need for novel therapeutic strategies. The Mediterranean diet is renowned for its cardiovascular benefits, largely attributed to extra virgin olive oil (EVOO) and its phenolic compounds, particularly hydroxytyrosol (HT). HT, a potent antioxidant and anti-inflammatory agent, has demonstrated significant therapeutic potential in mitigating myocardial damage following acute myocardial infarction (AMI). However, there is a notable lack of published evidence regarding the effects of HT administration in the context of acute ischemia/reperfusion (I/R) injury, making this study a novel contribution to the field. This study aimed to evaluate the cardioprotective effects of HT using the Langendorff technique in an isolated mouse heart ischemia/reperfusion (I/R) model. Mice were administered a single intraperitoneal dose of HT (10 mg/kg) 24 h prior to the I/R protocols, and parameters such as the infarct size, mitochondrial function, and redox balance were assessed. The results revealed a remarkable 57% reduction in infarct size in HT-treated mice compared to untreated controls. HT treatment also improved mitochondrial bioenergetics, as evidenced by the increased membrane potential (ΔΨm), enhanced oxygen consumption, and reduced hydrogen peroxide (H₂O₂) production. Furthermore, HT restored the activity of the mitochondrial respiratory complexes, notably Complex I, even under I/R conditions. These findings highlight the efficacy of HT in reducing oxidative stress and preserving mitochondrial function, critical factors in cardiac disease. In conclusion, HT emerges as a promising therapeutic agent for ischemic heart disease, demonstrating both preventive and restorative potential. Future research should explore its clinical applicability to advance cardiovascular disease management. Full article

Surgical myocardial revascularization, regardless of the technique used, causes ischemia–reperfusion injury (IRI) in the myocardium mediated by inflammation and degradation of the endothelial glycocalyx (EG). We investigated the difference between on-pump and off-pump techniques in terms of the concentration of proinflammatory interleukin (IL)-18 and the EG degradation products syndecan-1 and hyaluronic acid measured by ELISA in the peripheral and cardiac circulation during open heart surgery and in the early postoperative period. The concentration of IL-18, C-reactive protein (CRP), and cardiac troponin T (cTnT) and the leukocyte count increased statistically significantly in revascularized patients at 24 and 72 h after revascularization compared to the beginning of the procedure and was always statistically significantly higher in on-pump patients. Syndecan-1 and hyaluronic acid only increased in on-pump patients 24 and 72 h after revascularization. IL-18 correlated positively with syndecan-1 and CRP only in the pump setting and with the number of leukocytes in both revascularization regimens 24 and 72 h after the surgery. cTnT and hyaluronic acid did not correlate with IL-18. Our results suggest that IL-18 plays an important role in the early inflammatory response in patients during open heart surgery and in the early postoperative period, leading to additional damage to the EG, while it is probably not responsible for myocardial necrosis. It could serve as a biomarker to identify high-risk patients and as a therapeutic target to reduce inflammation and EG degradation. In addition, measurement of IL-18 could help improve the treatment, recovery, and outcomes of patients after heart surgery. Full article

Objectives: Contrast-induced acute kidney injury (CI-AKI) remains a frequent and serious complication after cardiac catheterization. Sirtuin-1 (SIRT1), a NAD+-dependent deacetylase, plays a central role in renal protection against ischemia-reperfusion injury, inflammation, and vascular dysfunction. We aimed to investigate whether serum SIRT1 levels could serve as an early diagnostic biomarker for CI-AKI. Methods: This prospective case-control study included 50 patients undergoing elective percutaneous coronary intervention (PCI) for stable angina. Serum SIRT1 levels were measured at baseline, 24 h, and 72 h post-PCI. The occurrence of CI-AKI was defined by a standard rise in serum creatinine, and patients were stratified accordingly. Results: Although SIRT1 levels tended to be lower in patients who developed CI-AKI (n = 17) compared to those without (n = 33), the differences were not statistically significant at any time point (p > 0.05). However, a significant between-group difference was observed in the 72-h change in SIRT1 levels (Δ0–72 h, p = 0.037), with a greater decline in the CI-AKI group. Multivariable logistic regression also revealed a trend-level inverse association between 72-h SIRT1 levels and CI-AKI (β = −0.536, p = 0.099). Conclusions: While SIRT1 is biologically plausible as a renal protective factor, our findings suggest that serial SIRT1 measurement may offer added value as a dynamic biomarker rather than a static diagnostic tool. Confirmatory trials incorporating serial SIRT1 measurements may help translate this molecular signal into clinically actionable tools for early detection of CI-AKI. Full article

Ginnalin A (GA), a polyphenolic compound derived from amur maple trees, has been identified as a powerful scavenger of reactive oxygen species (ROS). Recognizing the pivotal role of ROS in exacerbating secondary damage during myocardial ischemia-reperfusion injury (MIRI), we fractionated GA-enriched extracts from the leaves of the amur maple tree, Acer tataricum L. subsp. ginnala (Maxim.) Wesm., using common solvents of dichloromethane (DCM) and ethyl acetate (EA). When co-administered for 30 min, the DCM- and EA-fractioned extracts effectively protected cardiomyocytes from H₂O₂-induced damage. ROS-sensitive probes indicated that treatment with ginnala extracts significantly reduced both intracellular and mitochondrial ROS levels. Instead of enhancing the activity of antioxidative enzymes, the ginnala extracts acted as natural antioxidases, directly scavenging various ROS such as superoxide, H₂O₂, hydroxyl radical, and Fe²⁺ within just 20 min. In a MIRI rat model, the in vivo administration of ginnala extracts provided significant cardioprotection by preserving viable myocardia and enhancing cardiac functions. Additionally, treatment with ginnala extracts significantly reduced cardiac fibrosis and denatured collagen. Our study suggests that the ultrafast ROS scavenging capability of ginnala extracts offers substantial heart protection during MIRI. Incorporating ginnala extracts as a pharmacological intervention during reperfusion could effectively mitigate ROS-induced cardiac injury. Full article

Mitochondrial ATP-sensitive K+ channels are closely linked to cardioprotection and are potential therapeutic targets during ischemia reperfusion (IR) injury. The renal outer medullary K+ channel isoform 2 (ROMK2) is an ATP-sensitive K+ channel found in the mitochondria of cardiomyocytes. While the germline knockout of ROMK does not mediate myocardial IR injury, the effect of ROMK loss of function on IR injury in the adult myocardium is unknown. By using a selective small molecule inhibitor of ROMK, we paradoxically found that mouse hearts were protected from IR injury after ROMK inhibition compared to vehicle-treated animals. In addition, we found that ROMK inhibition leads to exaggerated mitochondrial uncoupling and increased ROS production. Phosphatidylinositol 4,5-bisphosphate (PIP₂), an activator of ROMK, increased the effect of ATP to hyperpolarize cardiac mitochondrial membrane potential. ROMK inhibition also increased mitochondrial swelling in the absence of ATP. In conclusion, pharmacologic ROMK inhibition protects the murine heart from IR injury and may promote a phenotype of enhanced mitochondrial matrix K+. ROMK may be more important during conditions that promote mitochondrial matrix K+ efflux than influx. Further research to understand its role in mitochondrial K+ handling and as a therapeutic target in IR injury is needed. Full article

Myocardial oxidative stress increases under conditions of hyperglycemia and ischemia/reperfusion (I/R) injury, leading to cellular damage. Inhibition of oxidative stress is involved in the cardioprotective effects of hydrogen sulfide (H₂S) during I/R and diabetes, and H₂S has the potential to protect the heart. However, the mechanism by which H₂S regulates the level of cardiac reactive oxygen species (ROS) during I/R and hyperglycemic conditions remains unclear. Therefore, the objective of this study was to evaluate the cytoprotective effect of H₂S in primary cardiomyocyte cultures subjected to hyperglycemia, hypoxia–reoxygenation (HR), or both conditions, by assessing the PPAR-α/Keap1/Nrf2/p47phox/NOX4/p-eNOS/CAT/SOD and the PPAR-γ/PGC-1α/AMPK/GLUT4 signaling pathways. Treatment with NaHS (100 μM) as an H₂S donor in cardiomyocytes subjected to hyperglycemia, HR, or a combination of both increased cell viability, total antioxidant capacity, and tetrahydrobiopterin (BH₄) concentrations, while reducing ROS production, malondialdehyde concentrations, 8-hydroxy-2′-deoxyguanosine, and dihydrobiopterin (BH₂) concentrations. Additionally, the H₂S donor treatment increased the expression and activity of PPAR-α, reversed the reduction in the expression of PPAR-γ, PGC-1α, AMPK, GLUT4, Nrf2, p-eNOS, SOD, and CAT, and decreased the expression of Keap1, p47phox and NOX4. Therefore, the treatment with the H₂S donor protects cardiomyocytes from damage caused by hyperglycemia, HR, or both conditions by reducing oxidative stress markers and improving antioxidant mechanisms, thereby increasing cell viability and “cardiomyocyte ultrastructure”. Full article

Myocardial ischemia–reperfusion injury (MI/R) is a negative and adverse cardiovascular outcome following myocardial ischemia, cardiac surgery, or circulatory arrest. Prolyl endopeptidase (PREP) appears to be involved in inflammatory responses, so it could be a possible therapeutic target for counteracting ischemia injury. This study aimed to investigate the role of PREP inhibitor, KYP-2047 (4-phenylbutanoyl-l-prolyl-2(S)-cyanopyrolidine), in the modulation of molecular and biochemical processes involved in MI/R. MI/R was induced through coronary artery occlusion (15 min), followed by reperfusion (2 h). KYP-2047 was intraperitoneally administrated at doses of 2.5 mg/kg and 5 mg/kg 24 h before the surgical procedures. The hearts were removed and processed for analysis. KYP-2047 treatment limited ischemic myocardial-induced histological damage and neutrophil accumulation, limiting inflammation, fibrosis, and apoptosis processes. Additionally, KYP-2047 was able to modulate p-38 and p-ERK expression, suggesting an improving role in recovering cardiac function. These findings highlighted the protective effects of KYP-2047 pretreatment in MI/R injury, suggesting PREP as a potential target therapy for the pathogenesis of MI/R. Although the molecular mechanisms underlying the action of KYP-2047 are still to be explored, these results suggested that the regulation of NF-κB, apoptosis, and MAPK pathways by KYP-2047 treatment could preventatively limit the damage caused by MI/R. Full article

Cardiovascular disease (CVD) is a serious global health issue with high mortality rates worldwide. Despite the numerous advancements in the study of CVD pathogenesis in recent years, further summarization and elaboration of specific molecular pathways are required. An extensive body of research has been conducted to elucidate the association between the MAPK signaling pathway, which is present in all eukaryotic organisms, and the pathogenesis of cardiovascular disease. This review aims to provide a comprehensive summary of the research conducted on MAPK and CVD over the past five years. The primary focus is on four specific diseases: heart failure, atherosclerosis, myocardial ischemia–reperfusion injury, and cardiac hypertrophy. The review will also address the pathophysiological mechanisms of MAPK in cardiovascular diseases, with the objective of proposing novel clinical treatment strategies for CVD. Full article

Delayed reperfusion of the ischemic heart (I/R) is known to impair the recovery of cardiac function and produce a wide variety of myocardial defects, including ultrastructural damage, metabolic alterations, subcellular Ca²⁺-handling abnormalities, activation of proteases, and changes in cardiac gene expression. Although I/R injury has been reported to induce the formation of reactive oxygen species (ROS), inflammation, and intracellular Ca²⁺ overload, the generation of oxidative stress is considered to play a critical role in the development of cardiac dysfunction. Increases in the production of superoxide, hydroxyl radicals, and oxidants, such as hydrogen peroxide and hypochlorous acid, occur in hearts subjected to I/R injury. In fact, mitochondria are a major source of the excessive production of ROS in I/R hearts due to impairment in the electron transport system as well as activation of xanthine oxidase and NADPH oxidase. Nitric oxide synthase, mainly present in the endothelium, is also activated due to I/R injury, leading to the production of nitric oxide, which, upon combination with superoxide radicals, generates nitrosative stress. Alterations in cardiac function, sarcolemma, sarcoplasmic reticulum Ca²⁺-handling activities, mitochondrial oxidative phosphorylation, and protease activation due to I/R injury are simulated upon exposing the heart to the oxyradical-generating system (xanthine plus xanthine oxidase) or H₂O₂. On the other hand, the activation of endogenous antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, and the concentration of a transcription factor (Nrf2), which modulates the expression of various endogenous antioxidants, is depressed due to I/R injury in hearts. Furthermore, pretreatment of hearts with antioxidants such as catalase plus superoxide dismutase, N-acetylcysteine, and mercaptopropionylglycerine has been observed to attenuate I/R-induced subcellular Ca²⁺ handling and changes in Ca²⁺-regulatory activities; additionally, it has been found to depress protease activation and improve the recovery of cardiac function. These observations indicate that oxidative stress is intimately involved in the pathological effects of I/R injury and different antioxidants attenuate I/R-induced subcellular alterations and improve the recovery of cardiac function. Thus, we are faced with the task of developing safe and effective antioxidants as well as agents for upregulating the expression of endogenous antioxidants for the therapy of I/R injury. Full article

Brain injury and cerebral inflammation are frequent complications following cardiopulmonary bypass (CPB) resulting in neurocognitive dysfunction, encephalopathy, or stroke. We compared cerebral inflammation induced by del Nido and histidine-tryptophan-α-ketoglutarate (HTK) cardioplegia in a porcine model. Pigs underwent 90 min cardiac arrest using HTK (n = 9) or Jonosteril^®-based del Nido cardioplegia (n = 9), followed by a 120 min reperfusion. Brain biopsies were collected and analyzed for the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and cytokines. HTK induced a decrease in blood sodium, chloride, and calcium concentration (cross-clamp aorta: p_sodium < 0.01, p_chloride < 0.01, p_calcium < 0.01; 90 min ischemia: p_sodium < 0.01, p_chloride < 0.01, p_calcium = 0.03) compared to the more stable physiological electrolyte concentrations during del Nido cardioplegia. Hyponatremia and hypochloremia persisted after a 120 min reperfusion in the HTK group (p_sodium < 0.01, p_chloride = 0.04). Compared to del Nido, a higher mRNA expression of the proinflammatory cytokine IL-1β was detected in the frontal cortex (HTK: ∆Ct 6.5 ± 1.7; del Nido: ∆Ct 8.8 ± 1.5, p = 0.01) and the brain stem (HTK: ∆Ct 5.7 ± 1.5; del Nido: ∆Ct 7.5 ± 1.6, p = 0.02) of the HTK group. In conclusion, we showed comparability of HTK and del Nido for cerebral inflammation except for IL-1β expression. Based on our study results, we conclude that del Nido cardioplegia is a suitable and safe alternative to the conventional HTK solution. Full article

Postoperative atrial fibrillation (POAF) is the most common arrhythmia following cardiac surgery. This review critically explores the interplay between cardiopulmonary bypass (CPB) and aortic cross-clamping (ACC) times in POAF development. CPB disrupts systemic homeostasis by inducing inflammatory cascades, oxidative stress, and ischemia–reperfusion injury. Prolonged ACC times further exacerbate myocardial ischemia and structural remodeling, with durations exceeding 60–75 min consistently linked to an increased POAF risk. However, variability in outcomes across studies reveals the complex, multifactorial nature of POAF pathogenesis. Patient-specific variables, such as baseline comorbidities and myocardial protection strategies, modulate these risks, emphasizing the need for personalized surgical approaches. Despite advancements in myocardial protection techniques and anti-inflammatory strategies, the incidence of POAF remains persistently high, indicating a gap in translating mechanistic insights into effective interventions. Emerging biomarkers, including microRNAs (e.g., miR-21, miR-483-5p, etc.) and markers of myocardial injury like troponin I, offer potential for enhanced risk stratification and targeted prevention. However, their clinical applicability requires further validation in diverse patient populations. This review underscores the critical need for integrative research that combines clinical, molecular, and procedural variables to elucidate the nuanced interplay of factors driving POAF. Future directions include leveraging advanced intraoperative monitoring tools, refining thresholds for CPB and ACC times, and developing individualized perioperative protocols. Full article

In the heart, Connexin 43 (Cx43) is involved in intercellular communication through gap junctions and exosomes. In addition, Cx43-formed hemichannels at the plasma membrane are important for ion homeostasis and cellular volume regulation. Through its localization within nuclei and mitochondria, Cx43 influences the function of the respective organelles. Several cardiovascular diseases such as heart failure, ischemia/reperfusion injury, hypertrophic cardiomyopathy and arrhythmias are characterized by Cx43 downregulation and a dysregulated Cx43 function. Accordingly, a putative therapeutic approach of these diseases would include the induction of Cx43 expression in the damaged heart, albeit such induction may have both beneficial and detrimental effects. In this review we discuss the consequences of increasing cardiac Cx43 expression, and discuss this manipulation as a strategy for the treatment of cardiovascular diseases. Full article

Acute myocardial infarction, a leading cause of death globally, is often associated with cardiometabolic disorders such as atherosclerosis and metabolic syndrome. Metabolic treatment of these disorders can improve cardiac outcomes, as exemplified by the GLP-1 agonist semaglutide. Fibroblast growth factor 21 (FGF21), a novel metabolic regulator, plays pivotal roles in lipid mobilization and energy conversion, reducing lipotoxicity, inflammation, mitochondrial health, and subsequent tissue damage in organs such as the liver, pancreas, and heart. Here, we test the therapeutic efficacy of FGF21 in mice with ischemia–reperfusion (I/R) injury, a model of acute myocardial infarction. We employed the strategic method of coating the FGF21-encapsulating liposomal nanoparticles with a neutrophil membrane designed to camouflage FGF21 from macrophage-mediated efferocytotic clearance and promote its targeted accumulation at I/R foci due to the inherent neutrophilic attraction to the inflammatory site. Our findings revealed that the coated FGF21 nanoparticles markedly accumulated within the lesions with a prolonged half-life, in additional to the liver, leading to substantial improvements in cardiac performance by enhancing mitochondrial energetic function and reducing oxidative stress, inflammation, and cell death. Therefore, our research highlights a viable strategy for the enhanced delivery of therapeutical FGF21 analogs to lesions beyond the liver following myocardial infarction. Full article

Cardiac surgery-related acute kidney injury (CS-AKI) is a decrease in kidney function after open-heart surgery, affecting up to 50% of patients. The pathophysiology of CS-AKI involves ischemia–reperfusion injury, inflammation, and oxidative stress. Ubiquinone is a potent antioxidant, and we hypothesized that it could decrease both the incidence and severity of CS-AKI. The intervention group received ubiquinone (8 mg/kg/day) divided into three daily doses, while the control group received a placebo. The primary outcome was the incidence of CS-AKI, which was manifested as an increase in creatinine ≥26.5 µmol/L or a urine output below 0.5 mL/kg/h for 6 h. Out of 73 patients, 39.7% (N = 29) developed CS-AKI, including 35.3% of the ubiquinone group and 43.6% of the placebo group (X²(1,N = 73) = 0.4931, p = 0.4825). The secondary outcomes revealed that the ubiquinone group experienced reduced postoperative bleeding, with a median (IQR) drainage of 320 mL (230–415) compared to the drainage of 420 mL (242.5–747.5) in the placebo group (t(35.84) = 2.055, p = 0.047). The median hs-TnI level in the ubiquinone group was 239.5 ng/mL (113.25–382.75) after surgery compared to a level of 366 (234.5–672.5) ng/mL in the placebo group (p = 0.024). In conclusion, there was no significant difference in the incidence of CS-AKI between groups. Postoperative hs-TnI and bleeding were significantly reduced among patients receiving ubiquinone. Full article