In vivo and in vitro study on the regulatory mechanism of XiaoChaiHu decoction on PANoptosis in sepsis-induced cardiomyopathy.

ETHNOPHARMACOLOGICAL RELEVANCE: In accordance with the tenets of traditional Chinese medicine, sepsis is categorized into three distinct syndromes: heat syndrome, blood stasis syndrome, and deficiency syndrome. Xiaochaihu decoction (XCHD) has many functions, including the capacity to protect the liver, cholagogue, antipyretic, anti-inflammatory, and anti-pathogenic microorganisms. XCHD exerts the effect of clearing heat and reconciling Shaoyang. The XCHD contains many efficacious active ingredients, yet the mechanism of sepsis-induced cardiomyopathy (SIC) remains elusive. AIM OF THE STUDY: To investigate the molecular mechanisms underlying the protective effects of XCHD against SIC using an integrated approach combining network pharmacology and molecular biology techniques. MATERIALS AND METHODS: Network pharmacology methods identified the active ingredients, target proteins, and pathways affected by XCHD in the context of SIC. We conducted in vivo experiments using mice with lipopolysaccharide-induced SIC, evaluating cardiac function through echocardiography and histology. XCHD-containing serum was analyzed to determine its principal active components using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The effects of XCHD-containing serum on SIC were further tested in vitro in LPS-treated H9c2 cardiac cells. Protein expression levels were quantified via Western blotting and enzyme-linked immunosorbent assay (ELISA). Additionally, molecular docking was performed between the active components and ZBP1, a potential target protein. Overexpression of ZBP1 in H9c2 cells allowed for a deeper exploration of its role in modulating SIC-associated gene expression. RESULTS: UPLC-MS/MS identified 31 shared XCHD and XCHD-containing serum components. These included organic acids, terpenoids, and flavonoids, which have been identified as the active components of XCHD. Our findings revealed that XCHD alleviated LPS-induced myocardial injury, improved cardiac function, and preserved cardiomyocyte morphology in mice. In vitro studies, we demonstrated that XCHD-containing serum significantly suppressed the expression of inflammatory cytokines (IL-6, IL-1ß, and TNF-α) in LPS-induced H9c2 cells. Mechanistic investigations showed that XCHD downregulated genes associated with PANoptosis, a novel cell death pathway, suggesting its protective role in sepsis-damaged hearts. Conversely, overexpression of ZBP1 abolished the protective effects of XCHD and amplified PANoptosis-related gene expression. CONCLUSIONS: Our study provides the first evidence supporting the protective effects of XCHD against SIC, both in vitro and in vivo. The underlying mechanism involves the inhibition of ZBP1-initiated PANoptosis, offering new insights into treating SIC using XCHD.

The efficacy of levosimendan and dobutamine on reducing peripheral blood interleukin-6 levels and improving cardiac function in patients with septic cardiomyopathy: a comparative study.

In patients with severe septic cardiomyopathy, levosimendan has been found to improve myocardial contractility more effectively than dobutamine, although the underlying mechanisms remain unclear. This study aims to compare the effects of levosimendan and dobutamine on cardiac function and inflammatory markers in patients with septic cardiomyopathy, and to further investigate the advantages and disadvantages of both treatments. We included 40 patients with septic cardiomyopathy treated in the intensive care unit of our hospital from September 2020 to September 2023. The patients were randomly divided into a levosimendan group (n=20) and a dobutamine group (n=20). Plasma concentrations of interleukin-6 (IL-6), interleukin-1beta (IL-1ß), and tumor necrosis factor-alpha (TNF-α) were measured by immunofluorescence at the start of treatment, 24 hours, and 48 hours. Cardiac troponin I (cTnI) concentrations were determined by chemiluminescence, and left ventricular ejection fraction (LVEF) was measured using the Simpson method. After 24 hours of treatment, there were no significant differences in IL-6, IL-1ß, and TNFα levels between the two groups (P>0.05). However, at 48 hours, the IL-6 level in the levosimendan group was significantly lower than that in the dobutamine group (319.43±226.05 pg/ml vs. 504.57±315.20 pg/ml, P=0.039), while IL-1ß and TNF-α levels showed no significant differences (P>0.05). Additionally, the cTnI level in the levosimendan group was significantly lower than that in the dobutamine group (1.01±0.54 ng/ml vs. 1.40±0.63 ng/ml, P=0.042), and LVEF was significantly higher in the levosimendan group (50.60±6.11% vs. 46.90±4.95%, P=0.042). These findings suggest that levosimendan may reduce plasma IL-6 levels, alleviate myocardial injury, and improve myocardial contractility in patients with septic cardiomyopathy compared to dobutamine.

Metoprolol use is associated with improved outcomes in patients with sepsis-induced cardiomyopathy: an analysis of the MIMIC-IV database.

BACKGROUND: Metoprolol is commonly administered to critically ill patients; however, its effect on mortality in patients with sepsis-induced cardiomyopathy (SICM) remains uncertain. This study aimed to investigate the relationship between metoprolol use and mortality in patients with SICM. METHODS: Adults with SICM were identified from the MIMIC-IV database. The exposure of interest was metoprolol treatment. The outcomes assessed were 30-day mortality, 1-year mortality, and in-hospital mortality. Kaplan-Meier survival analysis evaluated the effect of metoprolol on these outcomes. Multivariable Cox proportional hazards and logistic regression analyses were performed to determine the correlation between metoprolol treatment and mortality in patients with SICM. RESULTS: 1163 patients with SICM were identified, with 882 receiving metoprolol treatment (MET group) and 281 not receiving metoprolol treatment (NOMET group). Overall, the 30-day, 1-year, and in-hospital mortality rates were 10.2%, 18.2%, and 8.9%, respectively. Significant differences in mortality existed between the groups. Multivariable Cox analysis revealed that patients in the NOMET group had a higher risk of 1-year mortality (adjusted hazard ratio [HR] 2.493; 95% confidence interval [CI] 1.800-3.451; P < 0.001) and 30-day mortality (adjusted HR 4.280; 95%CI 2.760-6.637; P < 0.001). Metoprolol treatment was associated with lower in-hospital mortality (odds ratio [OR] 5.076; 95% CI 2.848-9.047; P < 0.001). Subgroup analysis supported these findings. CONCLUSION: Metoprolol treatment is associated with reduced all-cause mortality in patients with SICM. Prospective studies are required to validate these findings.

Odoratin balances ROS/NO through EZH2/PPARγ signalling to improve myocardial fibrosis.

Myocardial fibrosis is a critical concern in clinical medicine. This study explores the potential of odoratin as a treatment for myocardial fibrosis and investigates its underlying mechanisms. In vitro experiments involved stimulating primary mouse cardiomyocytes with TGF-ß1, followed by odoratin treatment, to assess levels of reactive oxygen species (ROS) and nitric oxide (NO). In vivo, a mouse model of myocardial fibrosis was established using abdominal aortic constriction (AAC) and treated with odoratin. ROS and NO levels in myocardial tissue were then evaluated. Immunofluorescence and Western blotting analysis showed that odoratin reduced excess ROS, enhanced NO production and decreased fibrosis-related protein expression in vitro. In vivo, odoratin significantly improved cardiac function, reduced ROS, increased NO levels and mitigated fibrosis in AAC-induced mice. Both in vitro and in vivo, odoratin inhibited the expression of NADPH oxidase 4 and EZH2, while promoting the expression of phosphorylated endothelial nitric oxide synthase (p-eNOS) and PPARγ. The anti-fibrotic effects of odoratin were reversed by PPARγ antagonism, and EZH2 overexpression diminished PPARγ activation by odoratin. These findings suggest that odoratin may combat myocardial fibrosis by balancing ROS and NO through PPARγ activation, with EZH2 inhibition likely playing a key regulatory role.

Propofol Ameliorates Sepsis-Induced Myocardial Dysfunction via Anti-Apoptotic, Anti-Oxidative Properties, and mTOR Signaling.

BACKGROUND: Sepsis often leads to cardiomyopathy, contributing to increased mortality rates. 2,6-Diisopropylphenol (propofol), an anesthetic, has demonstrated efficacy in protecting cardiomyocytes from cell death caused by hypoxia and reoxygenation. This study examined the effects of propofol on sepsis-associated myocardial dysfunction and explored the underlying mechanism of action. METHODS: Mice and rat cardiomyocytes (H9C2 cell line) were used to establish a sepsis-induced myocardial dysfunction model. Lipopolysaccharides (LPS)-treated mice and H9C2 cells were treated with propofol, with rapamycin used for mechanistic studies in H9C2 cells. Cardiac function was evaluated by echocardiographic measurements. Heart tissues were stained with hematoxylin and eosin, and heart weight/body weight ratio along with the levels of cardiac biomarkers were measured using Enzyme Linked Immunosorbent Assay (ELISA). Activation of the mammalian target of rapamycin (mTOR) pathway was assessed by western blotting. Apoptosis in heart tissues and H9C2 cells was evaluated using Terminal deoxynucleotidyl transferase (TdT) dUTP nick end labeling (TUNEL) assay, and cell viability was quantified using Cell Counting Kit (CCK)-8 assay. Oxidative stress in H9C2 cells was assessed by measuring reactive oxygen species (ROS) levels through immunofluorescence staining and malondialdehyde (MDA) and superoxide dismutase (SOD) levels using ELISA. RESULTS: Propofol reversed LPS-induced myocardial changes and cardiac dysfunction (p < 0.05). In mouse tissues and H9C2 cells, propofol reversed LPS-induced mTOR pathway inhibition and apoptosis (p < 0.001). Moreover, propofol alleviated oxidative stress in LPS-treated cells. The activation of the mTOR pathway by propofol, along with its inhibitory effects on oxidative stress and apoptosis in cardiomyocytes, was negated by rapamycin (p < 0.001). CONCLUSION: Propofol ameliorates sepsis-induced myocardial dysfunction triggered by LPS through the mTOR pathway, thereby promoting antioxidative stress and reducing cell apoptosis.

[Mechanism of protective effect of metformin against septic cardiomyopathy based on the P38 MAPK/JNK signaling pathway].

Exploring the protective mechanism of metformin against septic cardiomyopathy based on the mitogen-activated protein kinase P38 (P38 MAPK)/c-Jun amino-terminal kinase (JNK) signaling pathway. This paper is an experimental animal study design, which was completed from January to December 2023 at the Xiangya Hospital, Central South University. Forty-eight 8-week-old female C57BL/6 mice were divided into four groups: group A (control group), group B (model group), group C (model+trimetazidine hydrochloride), and group D (model+metformin group), with 12 mice in each group, by using a randomized numeric table method. Groups B, C, and D were injected intraperitoneally with LPS (15 mg/kg) to construct a septic cardiomyopathy mouse model. 24 h after modeling, Groups A and B were injected intraperitoneally with an equal amount of saline, Group C was given 20 mg/kg trimetazidine hydrochloride by gavage, and Group D was injected with metformin 200 mg/kg intraperitoneally, and all of them were subjected to consecutive interventions for 14 d. The results were summarized in the following table. Ultrasound imaging system was used to detect cardiac function, and TUNEL method was used to detect apoptosis rate of myocardial tissues; real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect the levels of mRNA of JNK, P38 MAPK of P38 MAPK signaling pathway in the myocardial tissues of mice; Plasma creatine kinase isoenzyme (CK-MB), brain natriuretic peptide (BNP), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6) levels were measured by enzyme-linked immunosorbent assay (ELISA) in all groups of mice; and protein kinase C, and protein kinase C levels were measured by protein blotting in cardiac muscle tissue. Eplison isoform (PKCε), and Cavity protein-3 (Cav-3) protein expression in myocardial tissues. The results showed that compared with group A, left ventricular ejection fraction (LVEF) (79.51±6.62)%, left ventricular short-axis shortening (FS) (45.66±4.13), apoptosis rate (4.34±0.36)%, JNK (0.96±0.06), P38 MAPK (1.01±0.03), CK-MB (2.37±0.13) µg/L, BNP (21.36±3.47) ng/L, TNF-α (176.22±19.24) ng/L, IL-6 (35.43±3.84) ng/L, PKCε expression (1.98±0.26), Cav-3 expression (1.04±0.03) compared to apoptosis rates in groups B, C, and D (28.22±4.49, 22.45±3.69, 15.88±3.27), JNK (1.68±0.11, 1.32±0.18, 1.13±0.14), P38 MAPK (2.47±0.71,1.77±0.35,1.49±0.05), CK-MB (16.55±2.16, 12.63±1.98, 5.27±0.61), BNP (48.92±5.67, 33.78±4.11, 27.55±3.84), TNF-α (463.71±24.81, 335.71±36.71, 214.78±22.53), and IL-6 (78.57±6.36, 63.71±5.66, 52.47±5.47) expression were elevated, while left ventricular ejection fraction (LVEF) (49.38±5.27, 55.47±5.03, 62.26±5.14), left ventricular short-axis shortening (FS) (24.36±2.17, 30.43±3.29, 33.57±2.72), PKCε expression (1.33±0.21, 1.54±0.23, 1.75±0.22), and Cav-3 expression (0.47±0.06, 0.76±0.05, 0.85±0.04) were all down-regulated (F=113.020,67.657,219.539,206.222,227.977,88.455,6285.186,135.877,65.924,96.362,17.532,314.419,P<0.05). Compared with group B, apoptosis rate, JNK, P38 MAPK, CK-MB, BNP, TNF-α, and IL-6 expression were decreased, and LVEF, FS, PKCε, and Cav-3 expression were up-regulated in groups C and D. And group D was better than group C (P<0.05). In conclusion, metformin has a protective effect against septic cardiomyopathy, and the mechanism may be related to the inhibition of the activation of the P38 MAPK/JNK signaling pathway and the up-regulation of PKCε and Cav-3 expression.

Identification of potential therapeutic targets for nonischemic cardiomyopathy in European ancestry: an integrated multiomics analysis.

BACKGROUND: Nonischemic cardiomyopathy (NISCM) is a clinical challenge with limited therapeutic targets. This study aims to identify promising drug targets for NISCM. METHODS: We utilized cis-pQTLs from the deCODE study, which includes data from 35,559 Icelanders, and SNPs from the FinnGen study, which includes data from 1,754 NISCM cases and 340,815 controls of Finnish ancestry. Mendelian randomization (MR) analysis was performed to estimate the causal relationship between circulating plasma protein levels and NISCM risk. Proteins with significant associations underwent false discovery rate (FDR) correction, followed by Bayesian colocalization analysis. The expression of top two proteins, LILRA5 and NELL1, was further analyzed using various NISCM datasets. Descriptions from the Human Protein Atlas (HPA) validated protein expression. The impact of environmental exposures on LILRA5 was assessed using the Comparative Toxicogenomics Database (CTD), and molecular docking identified the potential small molecule interactions. RESULTS: MR analysis identified 255 circulating plasma proteins associated with NISCM, with 16 remaining significant after FDR correction. Bayesian colocalization analysis identified LILRA5 and NELL1 as significant, with PP.H4 > 0.8. LILRA5 has a protective effect (OR = 0.758, 95% CI, 0.670-0.857) while NELL1 displays the risk effect (OR = 1.290, 95% CI, 1.199-1.387) in NISCM. Decreased LILRA5 expression was found in NISCM such as diabetic, hypertrophic, dilated, and inflammatory cardiomyopathy, while NELL1 expression increased in hypertrophic cardiomyopathy. HPA data indicated high LILRA5 expression in neutrophils, macrophages and endothelial cells within normal heart and limited NELL1 expression. Immune infiltration analysis revealed decreased neutrophil in diabetic cardiomyopathy. CTD analysis identified several small molecules that affect LILRA5 mRNA expression. Among these, Estradiol, Estradiol-3-benzoate, Gadodiamide, Topotecan, and Testosterone were found to stably bind to the LILRA5 protein at the conserved VAL-15 or THR-133 residues in the Ig-like C2 domain. CONCLUSION: Based on European Ancestry Cohort, this study reveals that LILRA5 and NELL1 are potential therapeutic targets for NISCM, with LILRA5 showing particularly promising prospects in diabetic cardiomyopathy. Several small molecules interact with LILRA5, implying potential clinical implication.

Ruxolitinib-based senomorphic therapy mitigates cardiomyocyte senescence in septic cardiomyopathy by inhibiting the JAK2/STAT3 signaling pathway.

Background: Cellular senescence has emerged as a pivotal focus in cardiovascular research. This study investigates the previously unrecognized role of cellular senescence in septic cardiomyopathy (SCM) and evaluates senomorphic therapy using ruxolitinib (Rux) as a potential treatment option. Methods: We employed lipopolysaccharide (LPS)-induced neonatal rat cardiomyocytes (NRCMs) and two mouse models-LPS-induced and cecal ligation and puncture (CLP)-induced SCM models-to assess Rux's effects. RNA sequencing, western blotting (WB), quantitative polymerase chain reaction (qPCR), immunofluorescence, immunohistochemistry, senescence-associated ß-galactosidase (SA-ß-gal) assay, and other techniques were utilized to investigate underlying mechanisms. Results: Senescence-associated secretory phenotype (SASP) and cellular senescence markers were markedly elevated in LPS-induced NRCMs and SCM animal models, confirmed by the SA-ß-gal assay. Rux treatment attenuated SASP in vitro and in vivo, alongside downregulation of senescence markers. Moreover, Rux-based senomorphic therapy mitigated mitochondrial-mediated apoptosis, improved cardiac function in SCM mice, restored the balance of antioxidant system, and reduced reactive oxygen species (ROS) levels. Rux treatment restored mitochondrial membrane potential, mitigated mitochondrial morphological damage, and upregulated mitochondrial complex-related gene expression, thereby enhancing mitochondrial function. Additionally, Rux treatment ameliorated SCM-induced mitochondrial dynamic dysfunction and endoplasmic reticulum stress. Mechanistically, Rux inhibited JAK2-STAT3 signaling activation both in vitro and in vivo. Notably, low-dose Rux and ABT263 showed comparable efficacy in mitigating SCM. Conclusions: This study highlighted the potential significance of cellular senescence in SCM pathogenesis and suggested Rux-based senomorphic therapy as a promising therapeutic approach for SCM.

Different Impact of Immunosuppressive Therapy on Cardiac Outcomes in Systemic Versus Isolated Cardiac Sarcoidosis.

Isolated cardiac sarcoidosis (iCS) is increasingly recognized; however, its prognosis and the efficacy of immunosuppressive therapy remain undetermined. We aimed to compare the prognosis of iCS and systemic sarcoidosis including cardiac involvement (sCS) under immunosuppressive therapy.We retrospectively reviewed the clinical data of 42 patients with sCS and 30 patients with iCS diagnosed at Kyushu University Hospital from 2004 through 2022. We compared the characteristics and the rate of adverse cardiac events including cardiac death, fatal ventricular tachyarrhythmia, and heart failure hospitalization between the 2 groups. The median follow-up time was 1535 [interquartile range, 630-2555] days, without a significant difference between the groups. There were no significant differences in gender, NYHA class, or left ventricular ejection fraction. Immunosuppressive agents were administered in 86% of sCS and in 73% of iCS patients (P = 0.191). When analyzed only with patients receiving immunosuppressive therapy (sCS, n = 36; iCS, n = 21), the cardiac event-free survival was significantly lower in iCS than sCS (37% versus 79%, P = 0.002). Myocardial LGE content at the initial diagnosis was comparable in both groups. The disease activity was serially evaluated in 26 sCS and 16 iCS patients by quantitative measures of FDG-PET including cardiac metabolic volume and total lesion glycolysis, representing 3-dimensional distribution and intensity of inflammation in the entire heart. Although iCS patients had lower baseline disease activity than sCS patients, immunosuppressive therapy did not attenuate disease activity in iCS in contrast to sCS.iCS showed a poorer response to immunosuppressive therapy and a worse cardiac prognosis compared to sCS despite lower baseline disease activity.

The effect of long-term tafamidis treatment on quality of life in people with transthyretin amyloid cardiomyopathy (ATTR-CM): A plain language summary.

WHAT IS THIS SUMMARY ABOUT?: This summary explains some results of a study called ATTR-ACT and its ongoing long-term extension study that were published in the European Journal of Heart Failure. The purpose of ATTR-ACT was to find out if a drug called tafamidis is an effective treatment for people with a heart condition called transthyretin amyloid cardiomyopathy (ATTR-CM). People took tafamidis or placebo for up to 2.5 years in ATTR-ACT (the initial study). A placebo looks like the study medicine but does not contain any active ingredients. After people completed the initial study, they could take part in the extension study. An extension study allows people to continue receiving treatment after the original clinical study ends and helps researchers understand how well a treatment works over a longer time period. This extension study allows people to receive tafamidis for up to an additional 5 years. People who took placebo in the initial study now receive tafamidis. People who took tafamidis in the initial study continue tafamidis treatment. Researchers looked at changes in peoples' ability to enjoy life ('quality of life') and heart failure symptoms since they started ATTR-ACT. Results are available for the first 2.5 years of the extension study. WHAT ARE THE KEY TAKEAWAYS?: During the initial study, there was less worsening of quality of life and heart failure symptoms in people who took tafamidis compared to people who took placebo. In the extension study, quality of life and heart failure symptoms were maintained or nearly maintained in people who took tafamidis in the initial study. In people who started tafamidis in the extension study, quality of life and heart failure symptoms continued to worsen, but the worsening slowed down. WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?: Tafamidis slows the worsening of quality of life and heart failure symptoms in people with ATTR-CM. People with ATTR-CM should start treatment early to receive the most benefit.Clinical Trial Registration: NCT01994889 (ATTR-ACT) (ClinicalTrials.gov).

The beneficial impact of curcumin on cardiac lipotoxicity.

Lipotoxicity is defined as a prolonged metabolic imbalance of lipids that results in ectopic fat distribution in peripheral organs such as the liver, heart, and kidney. The harmful consequences of excessive lipid accumulation in cardiomyocytes cause cardiac lipotoxicity, which alters the structure and function of the heart. Obesity and diabetes are linked to lipotoxic cardiomyopathy. These anomalies might be caused by a harmful metabolic shift that accumulates toxic lipids and shifts glucose oxidation to less fatty acid oxidation. Research has linked fatty acids, fatty acyl coenzyme A, diacylglycerol, and ceramide to lipotoxic stress in cells. This stress can be brought on by apoptosis, impaired insulin signaling, endoplasmic reticulum stress, protein kinase C activation, p38 Ras-mitogen-activated protein kinase (MAPK) activation, or modification of peroxisome proliferator-activated receptors (PPARs) family members. Curcuma longa is used to extract curcumin, a hydrophobic polyphenol derivative with a variety of pharmacological characteristics. Throughout the years, curcumin has been utilized as an anti-inflammatory, antioxidant, anticancer, hepatoprotective, cardioprotective, anti-diabetic, and anti-obesity drug. Curcumin reduces cardiac lipotoxicity by inhibiting apoptosis and decreasing the expression of apoptosis-related proteins, reducing the expression of inflammatory cytokines, activating the autophagy signaling pathway, and inhibiting the expression of endoplasmic reticulum stress marker proteins.

Salvianolic acid B improves mitochondrial dysfunction of septic cardiomyopathy via enhancing ATF5-mediated mitochondrial unfolded protein response.

AIMS: Septic cardiomyopathy is characterized by impaired contractile function and mitochondrial activity dysregulation. Salvianolic acid B (Sal B) is a potent therapeutic compound derived from the traditional Chinese medicine Salvia miltiorrhiza. This study explored the protective effects of Sal B on septic heart injury, emphasizing the mitochondrial unfolded protein response (UPRmt). MATERIALS AND METHODS: An in vivo mouse model of lipopolysaccharide (LPS)-induced heart injury was utilized to assess Sal B's protective role in septic cardiomyopathy. Additionally, cell models stimulated by LPS were developed to investigate the mechanisms of Sal B on UPRmt. Quantitative polymerase chain reaction, western blotting, immunohistochemistry, and immunofluorescence were employed for molecular analysis. RESULTS: Sal B, administered at doses of 10, 30, and 60 mg/kg, demonstrated protective effects on cardiac contractile function, reduced heart inflammation, and mitigated cardiac injury in LPS-exposed mice. In cardiomyocytes, LPS induced apoptosis, elevated mitochondrial ROS levels, promoted mitochondrial fission, and decreased mitochondrial membrane potential, all of which were alleviated by Sal B. Mechanistically, Sal B was found to induce UPRmt both in vivo and in vitro. ATF5, identified as a UPRmt activator, was modulated by LPS and Sal B, resulting in increased ATF5 expression and its translocation from the cytosol to the nucleus. ATF5-siRNA delivery reversed UPRmt upregulation, exacerbating mitochondrial dysfunction in LPS-stimulated cardiomyocytes and counteracting the mitochondrial function enhancement in Sal B-treated cardiomyocytes. CONCLUSIONS: This study provides evidence that Sal B confers cardiac protection by enhancing UPRmt, highlighting its potential as a therapeutic approach for mitigating mitochondrial dysfunction in septic cardiomyopathy.

Endothelial α1-adrenergic receptor activation improves cardiac function in septic mice via PKC-ERK/p38MAPK signaling pathway.

Cardiomyopathy is particularly common in septic patients. Our previous studies have shown that activation of the alpha 1 adrenergic receptor (α1-AR) on cardiomyocytes inhibits sepsis-induced myocardial dysfunction. However, the role of cardiac endothelial α1-AR in septic cardiomyopathy has not been determined. Here, we identified α1-AR expression in mouse and human endothelial cells and showed that activation of α1-AR with phenylephrine (PE) improved cardiac function and survival by preventing cardiac endothelial injury in septic mice. Mechanistically, activating α1-AR with PE decreased the expression of ICAM-1, VCAM-1, iNOS, E-selectin, and p-p38MAPK, while promoting PKC and ERK1/2 phosphorylation in LPS-treated endothelial cells. These effects were abolished by a PKC inhibitor or α1-AR antagonist. PE also reduced p65 nuclear translocation, but this suppression is not blocked by PKC inhibition. Treatment with U0126 (a specific ERK1/2 inhibitor) reversed the effects of PE on p38MAPK phosphorylation. Our results demonstrate that cardiac endothelial α1-AR activation prevents sepsis-induced myocardial dysfunction in mice by inhibiting the endothelial injury via PKC-ERK/p38MAPK signaling pathway and a PKC-independent inhibition of p65 nuclear translocation. These findings offer a new perspective for septic patients with cardiac dysfunction by inhibiting cardiac endothelial cell injury through α1-AR activation.

COX-2 optimizes cardiac mitochondrial biogenesis and exerts a cardioprotective effect during sepsis.

BACKGROUND: Septic cardiomyopathy is a component of multiple organ dysfunction in sepsis. Mitochondrial dysfunction plays an important role in septic cardiomyopathy. Studies have shown that cyclooxygenase-2 (COX-2) had a protective effect on the heart, and prostaglandin E2 (PGE2), the downstream product of COX-2, was increasingly recognized to have a protective effect on mitochondrial function. OBJECTIVE: This study aims to demonstrate that COX-2/PGE2 can protect against septic cardiomyopathy by regulating mitochondrial function. METHODS: Cecal ligation and puncture (CLP) was used to establish a mouse model of sepsis and RAW264.7 macrophages and H9C2 cells were used to simulate sepsis in vitro. The NS-398 and celecoxib were used to inhibit the activity of COX-2. ZLN005 and SR18292 were used to activate or inhibit the PGC-1α activity. The mitochondrial biogenesis was examined through the Mitotracker Red probe, mtDNA copy number, and ATP content detection. RESULTS: The experimental data suggested that COX-2 inhibition attenuated PGC-1α expression thus decreasing mitochondrial biogenesis, whereas increased PGE2 could promote mitochondrial biogenesis by activating PGC-1α. The results also showed that the effect of COX-2/PGE2 on PGC-1α was mediated by the activation of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB). Finally, the effect of COX-2/PGE2 on the heart was also verified in the septic mice. CONCLUSION: Collectively, these results suggested that COX-2/PGE2 pathway played a cardioprotective role in septic cardiomyopathy through improving mitochondrial biogenesis, which has changed the previous understanding that COX-2/PGE2 only acted as an inflammatory factor.

Post-COVID Myocarditis in Patients with Primary Cardiomyopathies: Diagnosis, Clinical Course and Outcomes.

The aim of this study was to evaluate the clinical course and outcomes of post-COVID myocarditis in patients with cardiomyopathies (CMP). This case series includes 10 patients with different CMPs who had COVID-19 (seven men; 48.4 ± 11.4 yr.): left ventricular non-compaction (n = 2), arrhythmogenic right ventricular CMP in combination with a heterozygous form of hemochromatosis (n = 1, HFE), restrictive CMP (n = 1, MyBPC3), laminopathy (n = 1, LMNA), dilated cardiomyopathy (n = 1, MYH7 + MyBPC3), Danon's disease (n = 1, LAMP2) and AL cardiac amyloidosis (n = 3). Myocardial morphological examination with immunohistochemical staining and PCR for SARS-CoV-2 and cardiotropic viruses was performed in six patients, while cardiac MRI and anti-cardiac antibody titres were evaluated in all patients. Post-COVID lymphocytic myocarditis was confirmed morphologically in six patients (with LVNC, RCM, ARCV, Danon's disease, and AL amyloidosis). Spike and nucleocapsid coronavirus proteins were detected in cell infiltrates, endothelium and cardiomyocytes in all biopsies; SARS-CoV-2 RNA was found in five out of six. In four patients, the diagnosis of myocarditis was based on MRI, high titres of anti-cardiac antibodies and clinical data. The mean time from COVID-19 to the diagnosis of myocarditis was 7 (5; 10.5) months. Myocarditis manifested with the onset/increase of arrhythmias and heart failure. Immunosuppressive therapy with corticosteroids was administered to six patients and led to an increase in ejection fraction and improvement of heart failure symptoms in five of them. CMPs are a favourable background for the development of post-COVID myocarditis. The onset or deterioration of heart failure and/or arrhythmias in patients with CMPs after COVID-19 requires the exclusion of myocarditis and, if present, the administration of immunosuppressive therapy.

Cyy-272, an indazole derivative, effectively mitigates obese cardiomyopathy as a JNK inhibitor.

Obesity has shown a global epidemic trend. The high-lipid state caused by obesity can maintain the heart in a prolonged low-grade inflammatory state and cause ventricular remodeling, leading to a series of pathologies, such as hypertrophy, fibrosis, and apoptosis, which eventually develop into obese cardiomyopathy. Therefore, prolonged low-grade inflammation plays a crucial role in the progression of obese cardiomyopathy, making inflammation regulation an essential strategy for treating this disease. Cyy-272, an indazole derivative, is an anti-inflammatory compound independently synthesized by our laboratory. Our previous studies revealed that Cyy-272 can exert anti-inflammatory effects by inhibiting the phosphorylation and activation of C-Jun N-terminal kinase (JNK), thereby alleviating lipopolysaccharide (LPS)-induced acute lung injury (ALI). The current study aimed to evaluate the potential of Cyy-272 to mitigate the occurrence and progression of obese cardiomyopathy through the inhibition of the JNK signaling pathway. Our results indicate that the compound Cyy-272 has encouraging therapeutic effects on obesity-induced cardiac injury. It significantly inhibits inflammation in cardiomyocytes and heart tissues induced by high lipid concentrations, further alleviating the resulting hypertrophy, fibrosis, and apoptosis. Mechanistically, the protective effect of Cyy-272 on obese cardiomyopathy can be attributed to its direct inhibition of JNK protein phosphorylation. In conclusion, we identified a novel compound, Cyy-272, capable of alleviating obese cardiomyopathy and confirmed that its effect is achieved through direct inhibition of JNK.

Monitoring the Efficacy of Tafamidis in ATTR Cardiac Amyloidosis by MRI-ECV: A Systematic Review and Meta-Analysis.

BACKGROUND: The usefulness of monitoring treatment effect of tafamidis using magnetic resonance imaging (MRI) extracellular volume fraction (ECV) has been reported. OBJECTIVE: we conducted a meta-analysis to evaluate the usefulness of this method. METHODS: Data from 246 ATTR-CMs from six studies were extracted and included in the analysis. An inverse variance meta-analysis using a random effects model was performed to evaluate the change in MRI-ECV before and after tafamidis treatment. The analysis was also performed by classifying the patients into ATTR-CM types (wild-type or hereditary). RESULTS: ECV change before and after tafamidis treatment was 0.33% (95% CI: -1.83-2.49, I2 = 0%, p = 0.76 for heterogeneity) in the treatment group and 4.23% (95% CI: 0.44-8.02, I2 = 0%, p = 0.18 for heterogeneity) in the non-treatment group. The change in ECV before and after treatment was not significant in the treated group (p = 0.76), but there was a significant increase in the non-treated group (p = 0.03). There was no difference in the change in ECV between wild-type (95% CI: -2.65-3.40) and hereditary-type (95% CI: -9.28-4.28) (p = 0.45). CONCLUSIONS: The results of this meta-analysis suggest that MRI-ECV measurement is a useful imaging method for noninvasively evaluating the efficacy of tafamidis treatment for ATTR-CM.

Antithrombotic properties of Tafamidis: An additional protective effect for transthyretin amyloid cardiomyopathy patients.

INTRODUCTION: Tafamidis is a molecular chaperone that stabilizes the transthyretin (TTR) homo-tetramer, preventing its dissociation and consequent deposition as amyloid fibrils in organ tissues. Tafamidis reduces mortality and the incidence of hospitalization for cardiovascular causes in patients with TTR amyloid (ATTR) cardiomyopathy. As ATTR cardiomyopathy is associated with a high risk of thromboembolic complications, we hypothesized that tafamidis may have a direct ancillary anti-thrombotic effect. METHODS: Primary human aortic endothelial cells (HAECs) were treated with tafamidis at clinically relevant concentrations and with plasma of patients, before and after the initiation of treatment with tafamidis. The expression of TF was induced by incubation with Tumor Necrosis Factor α (TNFα). Intracellular expression of tissue factor (TF) was measured by western blot. TF activity was measured by a colorimetric assay. Gene expressions of TF were measured by quantitative polymerase chain reaction. RESULTS: Treatment with tafamidis dose-dependently reduced the expression and activity of TNFα-induced TF. This effect was confirmed in cells treated with patients' plasma. Signal Transducer and Activator of Transcription 3 (STAT3) phosphorylation was significantly inhibited by tafamidis. Incubation of HAECs with tafamidis and the STAT3 activator colivelin partially rescued the expression of TF. CONCLUSIONS: Treatment with tafamidis lowers the thrombotic potential in human primary endothelial cells by reducing TF expression and activity. This previously unknown off-target effect may provide a novel mechanistic explanation for the lower number of thromboembolic complications in ATTR cardiomyopathy patients treated with tafamidis.

Targeting ferroptosis by natural products in pathophysiological conditions.

Ferroptosis is a form of cell death that is induced by iron-mediated accumulation of lipid peroxidation. The involvement of ferroptosis in different pathophysiological conditions has offered new perspectives on potential therapeutic interventions. Natural products, which are widely recognized for their significance in drug discovery and repurposing, have shown great promise in regulating ferroptosis by targeting various ferroptosis players. In this review, we discuss the regulatory mechanisms of ferroptosis and its implications in different pathological conditions. We dissect the interactions between natural products and ferroptosis in cancer, ischemia/reperfusion, neurodegenerative diseases, acute kidney injury, liver injury, and cardiomyopathy, with an emphasis on the relevance of ferroptosis players to disease targetability.