Neuregulins: protective and reparative growth factors in multiple forms of cardiovascular disease

Neuregulin-1 prevents death from a normally lethal respiratory viral infection

Respiratory infections with RNA viruses such as respiratory syncytial virus (RSV) and influenza lead to significant morbidity and mortality. Using a natural rodent pathogen, Sendai virus (SeV), which is similar to RSV, mice made atopic with house dust mite survived a normally lethal SeV infection. One protein that we found markedly elevated in the lungs and bronchoalveolar lavage fluid of atopic mice was neuregulin-1 (NRG1). Administration of NRG1 protected naïve (non-atopic) mice from death with both SeV and mouse adapted influenza A virus (IAV). Survival was associated with reduced alveolar epithelium permeability and reduced phosphorylation of mixed lineage kinase domain-like (MLKL) protein indicating inhibition of necroptosis. In vitro, treatment of mouse lung epithelial cells with NRG1 inhibited SeV induced necroptosis, and NRG1 administration to differentiated human bronchial epithelial cells infected with RSV reduced transepithelial fluid leak and expression of necroptosis associated genes RIPK3 and MLKL, while regulating genes associated with homeostatic maintenance, suggesting stabilized epithelial integrity. In conclusion, our data demonstrate a unique function of NRG1 in respiratory viral infections by reducing alveolar leak, inhibiting epithelial necroptosis, and promoting homeostatic regulation of airway epithelium, all of which associate with markedly reduced mortality to the respiratory viral insult.

Understanding uremic cardiomyopathy: from pathogenesis to diagnosis and the horizon of therapeutic innovations

Uremic cardiomyopathy (UC) is a significant cardiovascular complication in individuals with end-stage renal disease. This review aims to explore the multifaceted landscape of UC, including the key pathophysiological mechanisms, diagnostic challenges, and current therapeutic approaches. The prevalence of cardiac hypertrophy, as a hallmark of UC, is highlighted and some new insights to its intricate pathogenesis, involving uremic toxins, oxidative stress, and inflammatory responses is elucidated. Diagnostic complexities, including the absence of specific biomarkers, are discussed, and the need for advanced imaging modalities and emerging diagnostic strategies are emphasized. Current therapeutic interventions, although lacking specificity, are addressed, paving its way to the potential future directions in targeted therapies. The review concludes new insights into the critical importance of ongoing research and technological advancements which will enhance early detection, precision treatment, and ultimately improve outcomes for individuals with UC.

Protective role of Tongxinluo in mitigating myocardial fibrosis in mice with acute myocardial infarction via neuregulin-1 upregulation and Inhibition of endothelium-interstitial transition

Acute myocardial infarction (AMI) is a leading cause of heart failure, often accompanied by myocardial fibrosis (MF), characterized by excessive extracellular matrix accumulation. Endothelial-to-mesenchymal transition (EndMT) plays a key role in MF progression post-AMI. Neuregulin-1 (NRG-1), a growth factor with cardioprotective properties, has emerged as a potential therapeutic target. Tongxinluo (TXL), a traditional Chinese medicine, mitigates MF by upregulating NRG-1. This study elucidates the mechanisms underlying the protective effects of NRG-1 and TXL against MF following AMI. Left anterior descending artery ligation established a model for mice with AMI. Adeno-associated virus was used to modulate NRG-1 expression in the myocardium. Echocardiography assessed cardiac function, and histological staining was used to evaluate MF. Expression levels of markers for myofibroblasts (α-SMA, FSP-1) and endothelial cells (CD31, VE-cadherin) were analysed to investigate EndMT. The involvement of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling pathway in NRG-1's protective mechanism was validated using biochemical methods. Tongxinluo was administered to mice with AMI via gavage for 4 weeks, and its effects on cardiac function, MF and EndMT were assessed. Overexpression of NRG-1 in mice with AMI ameliorated cardiac dysfunction and reduced interstitial and perivascular fibrosis, whereas NRG-1 deficiency exacerbated these effects. NRG-1 protected against EndMT, as evidenced by changes in myofibroblast and endothelial cell markers. The PI3K/AKT signalling pathway was involved in NRG-1's protective mechanism against MF. The administration of TXL to mice with AMI improved cardiac function and reduced MF by activating NRG-1. Furthermore, TXL inhibited EndMT post-AMI through the NRG-1/PI3K/AKT pathway. NRG-1 and TXL protect against MF post-AMI by mitigating EndMT through the PI3K/AKT pathway. These findings suggest that targeting NRG-1 or using TXL may be promising therapeutic strategies for MF following AMI.

Advance in peptide-based drug development: delivery platforms, therapeutics and vaccines

The successful approval of peptide-based drugs can be attributed to a collaborative effort across multiple disciplines. The integration of novel drug design and synthesis techniques, display library technology, delivery systems, bioengineering advancements, and artificial intelligence have significantly expedited the development of groundbreaking peptide-based drugs, effectively addressing the obstacles associated with their character, such as the rapid clearance and degradation, necessitating subcutaneous injection leading to increasing patient discomfort, and ultimately advancing translational research efforts. Peptides are presently employed in the management and diagnosis of a diverse array of medical conditions, such as diabetes mellitus, weight loss, oncology, and rare diseases, and are additionally garnering interest in facilitating targeted drug delivery platforms and the advancement of peptide-based vaccines. This paper provides an overview of the present market and clinical trial progress of peptide-based therapeutics, delivery platforms, and vaccines. It examines the key areas of research in peptide-based drug development through a literature analysis and emphasizes the structural modification principles of peptide-based drugs, as well as the recent advancements in screening, design, and delivery technologies. The accelerated advancement in the development of novel peptide-based therapeutics, including peptide-drug complexes, new peptide-based vaccines, and innovative peptide-based diagnostic reagents, has the potential to promote the era of precise customization of disease therapeutic schedule.

Neuregulin-4 alleviates isoproterenol (ISO)-induced cardial remodeling by inhibiting inflammation and apoptosis via AMPK/NF-κB pathway

Cardiac remodeling refers to the abnormal changes in cardiac structure and function caused by various pathological conditions. It is an inevitable pathological process in the occurrence and development of heart failure and is related to a variety of cardiovascular diseases. Inflammation and apoptosis are critical pathological processes involved in cardiac remodeling. Neuregulin 4 (Nrg 4) is an adipokine produced primarily by brown adipose tissue that may play a protective role in a variety of inflammatory diseases. The aim of this study was to investigate whether Nrg4 can delay the progression of cardiac remodeling by regulating AMPK/NF-κB pathway, inhibiting inflammation and apoptosis. In our study, we established a model of cardiac remodeling in mice after 14 days of isoproterenol (ISO) intervention, and then gave Nrg4 treatment for another 4 weeks. The cardiac function, the degree of myocardial hypertrophy and myocardial fibrosis of the mice were observed. At the same time, the levels of apoptosis-related proteins (Bax,Bcl-2,Caspase-3), IL-6,IL-Iβ and TNF-α, as well as the activation level of AMPK/NF-κB signaling pathway were evaluated.Nrg4 alleviated ISO-induced cardiac dysfunction, cardiac hypertrophy and fibrosis in mice. Nrg4 also attenuated ISO-induced apoptosis and reduces levels of inflammatory factors to protect ISO-induced myocardial damage. At the same time, the effect of Nrg4 on AMPK/NF-κB pathway was measured in vivo and in vitro. The administration of an AMPK inhibitor was found to reverse the anti-hypertrophy, anti-inflammatory, and anti-apoptotic effects of Nrg4. Our findings suggest that Nrg4 may play a protective role in cardiac remodeling by inhibiting inflammation and apoptosis via AMPK/NF-κB pathway.

Low circulating levels of neuregulin 4 as a potential biomarker associated with the severity and prognosis of obesity-related metabolic diseases: a systematic review

BACKGROUND

Neuregulin 4 (Nrg4) is a brown adipose tissue-derived adipokine that greatly affects systemic metabolism and improves metabolic derangements. Although abnormal circulating levels of Nrg4 are common in obesity, it remains elusive whether low or elevated levels of this batokine are associated with the onset of metabolic diseases.

AIM

To assess Nrg4 levels and its role as a feasible biomarker to predict the severity of obesity, gestational diabetes mellitus (GDM), type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases (CVD).

METHODS

A search for relevant studies was performed systematically using prominent search engines, including PubMed, Google Scholar, and Embase, by following PRISMA guidelines.

RESULTS

Ample clinical evidence reported low serum/plasma levels of Nrg4 in obesity and these were inversely proportional to the indices of metabolic syndrome, including body mass index, waist circumference, triglycerides, fasting plasma glucose, and homoeostatic model assessment for insulin resistance as well as high-sensitivity C-reactive protein. Low circulating Nrg4 levels may aid in the prediction of morbid obesity, and subsequent GDM, T2DM, NAFLD, and CVD.

CONCLUSION

Current clinical evidence emphasizes that the circulating levels of Nrg4 are decreased in morbid obesity, and it also highlights that Nrg4 May serve as a potential prognostic biomarker for obesity-related metabolic diseases.

The Potential of Neuregulin 4 as a Novel Biomarker and Therapeutic Agent for Vascular Complications in Type 2 Diabetes Mellitus

Neuregulin 4 (Nrg4), a novel adipokine produced primarily by brown adipose tissue (BAT), has been functionally characterized to exert beneficial effects on modulating energy homeostasis and glucolipid metabolism, and is closely associated with the development and progression of obesity and obesity-associated metabolic diseases, such as type 2 diabetes mellitus (T2DM) and cardiovascular diseases. Recently, there has been a growing focus on the relationship between circulating Nrg4 levels and T2DM-related vascular complications. In this review, we discussed the known and potential roles of Nrg4 in various physiological and pathological processes, and its association with vascular complications in T2DM, in the aim of finding a potential biomarker recommended for the clinical diagnosis, prognosis and follow-up of T2DM patients at high risk of developing vascular complications as well as providing new therapeutic approaches.

A region on chromosome 16 is associated with Doberman Pinscher dilated cardiomyopathy

Doberman Pinschers are known for their increased susceptibility to dilated cardiomyopathy (DCM) relative to other domestic dogs. This makes the Doberman Pinscher a key model for gene-disease investigations. We conducted a genome-wide association study (GWAS) leveraging a database of genetic profiles obtained through collaboration with the Doberman Diversity Project (DDP). We worked in parallel to increase the depth and power of the DDP database. We exchanged direct correspondences with listed breeders and owners to establish health updates for participant dogs. In total, our study included data on 216, 184 single nucleotide polymorphisms (SNPs) in 46 cases and 3226 population control Doberman Pinschers. Using a generalized linear mixed model and saddlepoint approximation to correct for unbalanced group sizes, we identified a cluster of SNPs associated with DCM on chromosome 16.

Blood Growth Factor Levels in Patients with Systemic Lupus Erythematosus: High Neuregulin-1 Is Associated with Comorbid Cardiovascular Pathology

Patients with systemic lupus erythematosus (SLE) are known to frequently suffer from comorbid cardiovascular diseases (CVDs). There are abundant data on cytokine levels and their role in the pathogenesis of SLE, while growth factors have received much less attention. The aim of this study was to analyze growth factor levels in SLE patients and their association with the presence of comorbid CVDs. The serum concentrations for the granulocyte-macrophage colony-stimulating factor (GM-CSF), nerve growth factor β (NGFβ), glial cell line-derived neurotrophic factor (GDNF), and neuregulin-1 β (NRG-1β) were determined in the SLE patients (n = 35) and healthy individuals (n = 38) by a Luminex multiplex assay. The NGFβ and NRG-1β concentrations were shown to be significantly higher in the total group of SLE patients (median [Q1-Q3]: 3.6 [1.3-4.5] and 52.5 [8.5-148], respectively) compared with the healthy individuals (2.9 [1.3-3.4] and 13.7 [4.4-42] ng/mL, respectively). The GM-CSF and GDNF levels did not differ. Interestingly, elevated NRG-1β levels were associated with the presence of CVDs, as SLE patients with CVDs had significantly higher NRG-1β levels (99 [22-242]) compared with the controls (13.7 [4.4-42]) and patients without CVDs (19 [9-80] ng/mL). The model for the binary classification of SLE patients with and without CVDs based on the NRG-1β level had an average predictive ability (AUC = 0.67). Thus, altered levels of growth factors may be associated with comorbid CVDs in SLE patients.

Neuregulin 1 Signaling Attenuates Tumor Necrosis Factor α-Induced Female Rat Luteal Cell Death

The corpus luteum (CL) is a transient ovarian endocrine structure that maintains pregnancy in primates during the first trimester and in rodents during the entire pregnancy by producing steroid hormone progesterone (P4). CL lifespan, growth, and differentiation are tightly regulated by survival and cell death signals through luteotrophic and luteolytic factors, including the epidermal growth factor (EGF)-like factor family. Neuregulin 1 (NRG1), a member of the EGF family, mediates its effect through ErbB2/3 receptors. However, the functional role of NRG1 in luteal cells (LCs) is unknown. Thus, this study investigated the role of NRG1 and its molecular mechanism of action in rat LC. Our experimental results suggest a strong positive correlation between steroidogenic acute regulatory protein (StAR) and NRG1 expression in mid-CL and serum P4 and estrogen (E2) production. In contrast, there was a decrease in StAR and NRG1 expression and P4 and E2 production with an increase in tumor necrosis factor α (TNFα) expression in regressing CL. Further in vitro studies in LCs showed that the knockdown of endogenous Nrg1 promoted the expression of proinflammatory and proapoptotic factors and decreased prosurvival factor expression. Subsequently, treatment with exogenous TNFα under these experimental conditions profoundly elevated proinflammatory and proapoptotic factors. Further analysis demonstrated that the phosphorylation status of ErbB2/3, PI3K, Ak strain transforming or protein kinase B (Akt), and ErK1/2 was significantly inhibited under these experimental conditions, whereas the treatment of TNFα further inhibited the phosphorylation of ErbB2/3, PI3K, Akt, and ErK1/2. Collectively, these studies provide new insights into the NRG1-mediated immunomodulatory and prosurvival role in LCs, which may maintain the function of CL.

Growth Factors and Their Application in the Therapy of Hereditary Neurodegenerative Diseases

Hereditary neurodegenerative diseases (hNDDs) such as Alzheimer's, Parkinson's, Huntington's disease, and others are primarily characterized by their progressive nature, severely compromising both the cognitive and motor abilities of patients. The underlying genetic component in hNDDs contributes to disease risk, creating a complex genetic landscape. Considering the fact that growth factors play crucial roles in regulating cellular processes, such as proliferation, differentiation, and survival, they could have therapeutic potential for hNDDs, provided appropriate dosing and safe delivery approaches are ensured. This article presents a detailed overview of growth factors, and explores their therapeutic potential in treating hNDDs, emphasizing their roles in neuronal survival, growth, and synaptic plasticity. However, challenges such as proper dosing, delivery methods, and patient variability can hinder their clinical application.

Targeting NPM1 Epigenetically Promotes Postinfarction Cardiac Repair by Reprogramming Reparative Macrophage Metabolism

BACKGROUND

Reparative macrophages play a crucial role in limiting excessive fibrosis and promoting cardiac repair after myocardial infarction (MI), highlighting the significance of enhancing their reparative phenotype for wound healing. Metabolic adaptation orchestrates the phenotypic transition of macrophages; however, the precise mechanisms governing metabolic reprogramming of cardiac reparative macrophages remain poorly understood. In this study, we investigated the role of NPM1 (nucleophosmin 1) in the metabolic and phenotypic shift of cardiac macrophages in the context of MI and explored the therapeutic effect of targeting NPM1 for ischemic tissue repair.

METHODS

Peripheral blood mononuclear cells were obtained from healthy individuals and patients with MI to explore NPM1 expression and its correlation with prognostic indicators. Through RNA sequencing, metabolite profiling, histology, and phenotype analyses, we investigated the role of NPM1 in postinfarct cardiac repair using macrophage-specific NPM1 knockout mice. Epigenetic experiments were conducted to study the mechanisms underlying metabolic reprogramming and phenotype transition of NPM1-deficient cardiac macrophages. The therapeutic efficacy of antisense oligonucleotide and inhibitor targeting NPM1 was then assessed in wild-type mice with MI.

RESULTS

NPM1 expression was upregulated in the peripheral blood mononuclear cells from patients with MI that closely correlated with adverse prognostic indicators of MI. Macrophage-specific NPM1 deletion reduced infarct size, promoted angiogenesis, and suppressed tissue fibrosis, in turn improving cardiac function and protecting against adverse cardiac remodeling after MI. Furthermore, NPM1 deficiency boosted the reparative function of cardiac macrophages by shifting macrophage metabolism from the inflammatory glycolytic system to oxygen-driven mitochondrial energy production. The oligomeric NPM1 recruited histone demethylase KDM5b to the promoter of Tsc1 (TSC complex subunit 1), the mTOR (mechanistic target of rapamycin kinase) complex inhibitor, reduced histone H3K4me3 modification, and inhibited TSC1 expression, which then facilitated mTOR-related inflammatory glycolysis and antagonized the reparative function of cardiac macrophages. The in vivo administration of antisense oligonucleotide targeting NPM1 or oligomerization inhibitor NSC348884 substantially ameliorated tissue injury and enhanced cardiac recovery in mice after MI.

CONCLUSIONS

Our findings uncover the key role of epigenetic factor NPM1 in impeding postinfarction cardiac repair by remodeling metabolism pattern and impairing the reparative function of cardiac macrophages. NPM1 may serve as a promising prognostic biomarker and a valuable therapeutic target for heart failure after MI.

Fluorescent Chiral Quantum Dots to Unveil Origin-Dependent Exosome Uptake and Cargo Release

Exosomes are promising nanocarriers for drug delivery. Yet, it is challenging to apply exosomes in clinical use due to the limited understanding of their physiological functions. While cellular uptake of exosomes is generally known through endocytosis and/or membrane fusion, the mechanisms of origin-dependent cellular uptake and subsequent cargo release of exosomes into recipient cells are still unclear. Herein, we investigated the intricate mechanisms of exosome entry into recipient cells and intracellular cargo release. In this study, we utilized chiral graphene quantum dots (GQDs) as representatives of exosomal cargo, taking advantage of the superior permeability of chiral GQDs into lipid membranes as well as their excellent optical properties for tracking analysis. We observed that the preferential cellular uptake of exosomes derived from the same cell-of-origin (intraspecies exosomes) is higher than that of exosomes derived from different cell-of-origin (cross-species exosomes). This uptake enhancement was attributed to receptor-ligand interaction-mediated endocytosis, as we identified the expression of specific ligands on exosomes that favorably interact with their parental cells and confirmed the higher lysosomal entrapment of intraspecies exosomes (intraspecies endocytic uptake). On the other hand, we found that the uptake of cross-species exosomes primarily occurred through membrane fusion, followed by direct cargo release into the cytosol (cross-species direct fusion uptake). We revealed the underlying mechanisms involved in the cellular uptake and subsequent cargo release of exosomes depending on their cell-of-origin and recipient cell types. Overall, this study envisions valuable insights into further advancements in effective drug delivery using exosomes, as well as a comprehensive understanding of cellular communication, including disease pathogenesis.

ALK inhibitors suppress HCC and synergize with anti-PD-1 therapy and ABT-263 in preclinical models

Hepatocellular carcinoma (HCC) currently lacks effective therapies, leaving a critical need for new treatment options. A previous study identified the anaplastic lymphoma kinase (ALK) amplification in HCC patients, raising the question of whether ALK inhibitors could be a viable treatment. Here, we showed that both ALK inhibitors and ALK knockout effectively halted HCC growth in cell cultures. Lorlatinib, a potent ALK inhibitor, suppressed HCC tumor growth and metastasis across various mouse models. Additionally, in an advanced immunocompetent humanized mouse model, when combined with an anti-PD-1 antibody, lorlatinib more potently suppressed HCC tumor growth, surpassing individual drug efficacy. Lorlatinib induced apoptosis and senescence in HCC cells, and the senolytic agent ABT-263 enhanced the efficacy of lorlatinib. Additional studies identified that the apoptosis-inducing effect of lorlatinib was mediated via GGN and NRG4. These findings establish ALK inhibitors as promising HCC treatments, either alone or in combination with immunotherapies or senolytic agents.

Neuregulin 1 as a potential biomarker for disease progression in moyamoya disease: A case-control study in Chinese population

OBJECTIVE

Moyamoya disease (MMD) is a rare and progressive stenosis of cerebral arteries characterized by abnormally proliferative vasculopathy. Current studies have demonstrated that Neuregulin 1 (NRG1) plays a key role in angiogenesis-related disorders. Thus, the aim of our study is to investigate the serum NRG1 levels and their clinical correlations in MMD patients.

METHODS

In this study, thirty adult patients with MMD and age-gender matched healthy controls were enrolled from our hospital between July 2020 and April 2022. Peripheral blood samples were collected at baseline, and clinical data were obtained from the electronic medical record system. Serum NRG1 concentrations were measured by enzyme-linked immunosorbent assay. Sanger sequencing was applied to detect the RNF213 p.R4810K mutation.

RESULTS

The serum NRG1 levels were significantly higher in MMD patients compared to controls (14.48 ± 10.81 vs.7.54 ± 6.35mmol/L, p < 0.001). No statistical difference in baseline clinical characteristics was found between both groups. Correlation analyses showed that NRG1 levels were positively associated with Suzuki staging (r = 0.4137, p = 0.023) while not related to other clinical features (reduced cerebral blood flow, posterior cerebral artery involvement, bilateral or unilateral steno-occlusive changes). Furthermore, subgroup analysis revealed that MMD patients with the RNF213 p.R4810K mutation presented with significantly higher NRG1 levels than those without the mutation (9.60 ± 0.929 vs. 25.89 ± 4.338 mmol/L, p = 0.001).

CONCLUSIONS

Our study suggests that increased serum NRG1 levels may constitute a characteristic feature of MMD, indicating a potential positive correlation with disease progression and the presence of the RNF213 mutation. This positions NRG1 as a potentially crucial target for further studies aimed at comprehending the pathogenesis of MMD.

Anti-inflammatory effects of neuregulin-1 in HaCaT keratinocytes and atopic dermatitis-like mice stimulated with Der p 38

Neuregulin (NRG)-1 plays fundamental roles in several organ systems after binding to its receptors, ErbB2 and ErbB4. This study examines the role of NRG-1 in atopic dermatitis (AD), a chronic skin disease that causes dryness, pruritus, and inflammation. In mice administered Der p 38, the skin presents AD-like symptoms including filaggrin downregulation and infiltration of neutrophils and eosinophils. Noticeably, there is an increased expression of NRG-1, ErbB2, and ErbB4 in the skin. Upregulation of these proteins is significantly correlated to the clinical skin severity score. In human keratinocyte HaCaT cells, exposure to Der p 38 decreased filaggrin expression, and NRG-1 alone had no effect on the expression. However, co-treatment of Der p 38 with NRG-1 enhanced the filaggrin expression decreased by Der p 38. Pre-treatment with AG879 (an ErbB2 inhibitor) or ErbB4 siRNA blocked the recovery of filaggrin expression in the cells after co-treatment with Der p 38 and NRG-1. Der p 38 treatment enhanced the secretion of interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1). Co-treatment of Der p 38 with NRG-1 lowered the cytokine secretion increased by Der p 38, although NRG-1 alone was not effective on cytokine alteration. Neutrophil apoptosis was not altered by NRG-1 or supernatants of cells treated with NRG-1, but the cell supernatants co-treated with Der p 38 and NRG-1 blocked the anti-apoptotic effects of Der p 38-treated supernatants on neutrophils, which was involved in the activation of caspase 9 and caspase 3. Taken together, we determined that NRG-1 has anti-inflammatory effects in AD triggered by Der p 38. These results will pave the way to understanding the functions of NRG-1 and in the future development of AD treatment.

Prediction and Validation of Hub Genes Related to Major Depressive Disorder Based on Co-expression Network Analysis

Major depressive disorder (MDD) is generally among the most prevalent psychiatric illnesses. Significant advances have occurred in comprehension of the MDD biology. However, it is still essential to recognize new biomarkers for potential targeted treatment of patients with MDD. The present work deals with in-depth comparative computational analyses to obtain new insights, such as gene ontology and pathway enrichment analyses and weighted gene co-expression network analysis (WGCNA) through gene expression dataset. The expression of selected hub-genes was validated in MDD patients using quantitative real-time PCR (RT-qPCR). We found that MDD progression includes the turquoise module genes (p-value = 1e-18, r = 0.97). According to gene enrichment analysis, the cytokine-mediated signaling pathway mostly involves genes in this module. By selection of four candidate hub-genes (IL6, NRG1, TNF, and BDNF), RT-qPCR validation was performed. A significant NRG1 downregulation was revealed by the RT-qPCR outcomes in MDD. In MDD patients, TNF and IL6 expression were considerably higher, and no considerable differences were found in the BDNF expression. Ultimately, based on ROC analyses, IL6, NRG1, and TNF had a higher MDD diagnostic performance. Therefore, our study presents information on the intricate association between MDD development and cytokine-mediated signaling, thus providing new rationales to develop new therapeutic approaches.

Fluorescent Chiral Quantum Dots to Unveil Origin-Dependent Exosome Uptake and Cargo Release

Exosomes are promising nanocarriers for drug delivery. Yet, it is challenging to apply exosomes in clinical use due to the limited understanding of their physiological functions. While cellular uptake of exosomes is generally known through endocytosis and/or membrane fusion, the mechanisms of origin-dependent cellular uptake and subsequent cargo release of exosomes into recipient cells are still unclear. Herein, we investigated the intricate mechanisms of exosome entry into recipient cells and the intracellular cargo release. In this study, we utilized chiral graphene quantum dots (GQDs) as representatives of exosomal cargo, taking advantage of the superior permeability of chiral GQDs into lipid membranes, as well as their excellent optical properties for tracking analysis. We observed a higher uptake rate of exosomes in their parental recipient cells. However, these exosomes were predominantly entrapped in lysosomes through endocytosis (intraspecies endocytic uptake). On the other hand, in non-parental recipient cells, exosomes exhibited a greater inclination for cellular uptake through membrane fusion, followed by direct cargo release into the cytosol (cross-species direct fusion uptake). We revealed the underlying mechanisms involved in the cellular uptake and the subsequent cargo release of exosomes depending on their cell-of-origin and recipient cell types. This study envisions valuable insights into further advancements in the effective drug delivery using exosomes, as well as a comprehensive understanding of cellular communication, including disease pathogenesis.

Multiomics Analysis Provides Novel Pathways Related to Progression of Heart Failure

BACKGROUND

Despite major advances in pharmacological treatment for patients with heart failure, residual mortality remains high. This suggests that important pathways are not yet targeted by current heart failure therapies.

OBJECTIVES

We sought integration of genetic, transcriptomic, and proteomic data in a large cohort of patients with heart failure to detect major pathways related to progression of heart failure leading to death.

METHODS

We used machine learning methodology based on stacked generalization framework and gradient boosting algorithms, using 54 clinical phenotypes, 403 circulating plasma proteins, 36,046 transcript expression levels in whole blood, and 6 million genomic markers to model all-cause mortality in 2,516 patients with heart failure from the BIOSTAT-CHF (Systems BIOlogy Study to TAilored Treatment in Chronic Heart Failure) study. Results were validated in an independent cohort of 1,738 patients.

RESULTS

The mean age of the patients was 70 years (Q1-Q3: 61-78 years), 27% were female, median N-terminal pro-B-type natriuretic peptide was 4,275 ng/L (Q1-Q3: 2,360-8,486 ng/L), and 7% had heart failure with preserved ejection fraction. During a median follow-up of 21 months, 657 (26%) of patients died. The 4 major pathways with a significant association to all-cause mortality were: 1) the PI3K/Akt pathway; 2) the MAPK pathway; 3) the Ras signaling pathway; and 4) epidermal growth factor receptor tyrosine kinase inhibitor resistance. Results were validated in an independent cohort of 1,738 patients.

CONCLUSIONS

A systems biology approach integrating genomic, transcriptomic, and proteomic data identified 4 major pathways related to mortality. These pathways are related to decreased activation of the cardioprotective ERBB2 receptor, which can be modified by neuregulin.

Hyperoside Protects Trastuzumab-Induced Cardiotoxicity via Activating the PI3K/Akt Signaling Pathway

PURPOSE

Trastuzumab is a landmark agent in the treatment of human epidermal growth factor receptor-2(HER2)-positive breast cancer. Nevertheless, trastuzumab also comes with unexpected cardiac side effects. Hyperoside is a natural product that serves beneficial roles in cardiovascular disease. This study aimed to explore the effect and mechanism of hyperoside in trastuzumab-induced cardiotoxicity.

METHODS

A female C57BL/6 mice cardiotoxicity model was established via intraperitoneally injecting with trastuzumab (10 mg/kg/day, once every other day, cumulative dosage to 40 mg/kg) with or without hyperoside (15 or 30 mg/kg/day) administration. In vitro, the H9c2 cells were exposed to 1 μM trastuzumab with or without hyperoside (100 or 200 μM) administration. Cardiac function was evaluated by echocardiographic, myocardial enzymes levels, and pathological section examinations. TUNEL staining and Annexin V-FITC/ propidium iodide flow cytometry were used to analyze the cardiomyocyte apoptosis.

RESULTS

Compared to the control group, the LVEF, LVFS was decreased and the concentrations of cTnT, CK, CK-MB and LDH in mice were significantly increased after treatment with trastuzumab. Collagen deposition and cardiomyocyte hypertrophy were observed in the myocardium of the trastuzumab group. However, these changes were all reversed by different doses of hyperoside. In addition, hyperoside attenuated trastuzumab-induced myocardium apoptosis and H9c2 cells apoptosis through inhibiting the expressions of cleaved caspase-3 and Bax. Trastuzumab abolished the PI3K/Akt signaling pathway in mice and H9c2 cells, while co-treatment of hyperoside effectively increased the ratio of p-Akt/Akt.

CONCLUSION

Hyperoside inhibited trastuzumab-induced cardiotoxicity through activating the PI3K/Akt signaling pathway. Hyperoside may be a promising therapeutic approach to trastuzumab-induced cardiotoxicity.

Is neuregulin-1 (NRG-1) a potential blood biomarker linking depression to obesity? A case-control study

BACKGROUND AND AIM

No definite biomarker linking depression and obesity has been found yet. Our study aimed to investigate neuregulin-1 (NRG-1) as a potential blood biomarker for this association.

METHODS

A case-control study was conducted on 108 obese subjects assigned for laparoscopic sleeve gastrectomy and 100 non-obese controls. Depression was assessed pre- and post-operatively. Serum NRG-1 was measured.

RESULTS

Pre-operatively depression was significantly higher among obese compared to non-obese patients. After the operation, 1.9% of the severely depressed subjects reported no depression, while 5.6% became moderately depressed; about 6% of the moderately depressed and 16% of the mildly depressed became not depressed. Serum NRG-1 level was significantly lower among obese and severely depressed compared to the controls. It was negatively correlated to the level of depression pre- and post-operative (r = -0.764 and -0.467 respectively). The sensitivity of serum NRG1 as a predictor for depression pre- and post-operative was 92.45% and 52.94% respectively. Specificity was 69.09% and 79.73% respectively at cut-off values of ≤ 3.5 and ≤ 2.5 ng/ml.

CONCLUSION

NRG-1 is a possible biomarker for the diagnosis of depression pre-bariatric surgery and the prediction of its prognosis post-operatively.

Neuregulin-1β Improves Uremic Cardiomyopathy and Renal Dysfunction in Rats

Chronic kidney disease is a global health problem affecting 10% to 12% of the population. Uremic cardiomyopathy is often characterized by left ventricular hypertrophy, fibrosis, and diastolic dysfunction. Dysregulation of neuregulin-1β signaling in the heart is a known contributor to heart failure. The systemically administered recombinant human neuregulin-1β for 10 days in our 5/6 nephrectomy-induced model of chronic kidney disease alleviated the progression of uremic cardiomyopathy and kidney dysfunction in type 4 cardiorenal syndrome. The currently presented positive preclinical data warrant clinical studies to confirm the beneficial effects of recombinant human neuregulin-1β in patients with chronic kidney disease.

Safety, Tolerability, and Pharmacokinetics of Recombinant Human Neuregulin-1 in Healthy Chinese Subjects

BACKGROUND

We investigated the safety, tolerability, and pharmacokinetics of intravenous recombinant human Neuregulin-1 (rhNRG-1), a DNA recombinant protein for the treatment of chronic heart failure, in healthy Chinese volunteers following single and multiple dose administration.

METHODS AND RESULTS

To evaluate the safety and tolerance after single-dosing escalation, 28 subjects were divided into six groups (0.2, 0.4, 0.8, 1.2, 1.6, and 2.4 μg/kg) to receive an intravenous (IV) infusion of rhNRG-1 over 10 min by a randomized, open-label design. Only the 1.2 μg/kg dose group obtained pharmacokinetic parameters: C_max was 7.645 (24.21) ng/mL, AUC_0-t was 97.088 (21.41) min·ng/mL. To assess the safety and pharmacokinetics after multiple-dosing, 32 subjects were divided into four groups (0.2, 0.4, 0.8, and 1.2 μg/kg) to receive a 10-min IV infusion of rhNRG-1 for five consecutive days. After multiple dosing of 1.2 μg/kg, the C_max value at day 5 was 8.838 (51.6) ng/mL and the AUC_0-t value at day 5 was 109.890 (32.99) min·ng/mL. RhNRG-1 is rapidly cleared from the blood and has a short t_1/2 of about 10 min. The adverse events related to rhNRG-1 mainly included flat or inverted T wave and gastrointestinal reactions, all of which were mild.

CONCLUSIONS

It is concluded that rhNRG-1 is safe and well tolerated in healthy Chinese subjects at the dosing levels used in this study. The severity and frequency of adverse events did not increase with the prolongation of administration time.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry ( http://www.chictr.org.cn ) Identifier No. ChiCTR2000041107.

Integrated bioinformatics and machine learning algorithms reveal the critical cellular senescence-associated genes and immune infiltration in heart failure due to ischemic cardiomyopathy

Heart failure (HF) is the final stage of many cardiovascular illnesses and the leading cause of death worldwide. At the same time, ischemic cardiomyopathy has replaced valvular heart disease and hypertension as the primary causes of heart failure. Cellular senescence in heart failure is currently receiving more attention. In this paper, we investigated the correlation between the immunological properties of myocardial tissue and the pathological mechanisms of cellular senescence during ischemic cardiomyopathy leading to heart failure (ICM-HF) using bioinformatics and machine learning methodologies. Our goals were to clarify the pathogenic causes of heart failure and find new treatment options. First, after obtaining GSE5406 from the Gene Expression Omnibus (GEO) database and doing limma analysis, differential genes (DEGs) among the ICM-HF and control groups were identified. We intersected these differential genes with cellular senescence-associated genes (CSAG) via the CellAge database to obtain 39 cellular senescence-associated DEGs (CSA-DEGs). Then, a functional enrichment analysis was performed to elucidate the precise biological processes by which the hub genes control cellular senescence and immunological pathways. Then, the respective key genes were identified by Random Forest (RF) method, LASSO (Least Absolute Shrinkage and Selection Operator) algorithms, and Cytoscape's MCODE plug-in. Three sets of key genes were taken to intersect to obtain three CSA-signature genes (including MYC, MAP2K1, and STAT3), and these three CSA-signature genes were validated in the test gene set (GSE57345), and Nomogram analysis was done. In addition, we assessed the relationship between these three CSA- signature genes and the immunological landscape of heart failure encompassing immunological infiltration expression profiles. This work implies that cellular senescence may have a crucial role in the pathogenesis of ICM-HF, which may be closely tied to its effect on the immune microenvironment. Exploring the molecular underpinnings of cellular senescence during ICM-HF is anticipated to yield significant advances in the disease's diagnosis and therapy.

MOTS-c and aerobic exercise induce cardiac physiological adaptation via NRG1/ErbB4/CEBPβ modification in rats

AIMS

To determine the effects of the mitochondrial open reading frame of the 12S ribosomal RNA type-c (MOTS-c) and aerobic exercise on cardiac structure and function and explore the role of neuregulin-1 (NRG1)- ErbB2 receptor tyrosine kinase 4(ErbB4)- CCAAT-enhancer binding protein β (C/EBPβ) in cardiac physiological adaptation induced by MOTS-c and aerobic training.

MAIN METHODS

We used Hematoxylin-Eosin staining(HE)and Transmission Electron Microscope (TEM) to observe the cardiac myocardial structure, carotid artery catheterization to test cardiac function, and real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting to describe the changes of NRG1, ErbB4, C/EBPβ, and Gata in cardiac physiological adaptation.

KEY FINDINGS

MOTS-c and aerobic training significantly increased heart weight and heart weight index (HWI) (all p < 0.05). Aerobic exercise and MOTS-c treatment thickened myocardial fibers, with a tendency of hypertrophy. Heart rate (HR) (p < 0.001, p = 0.010, p = 0.011), the isovolumic diastolic time constant (Tau) (p < 0.001, p < 0.001, p < 0.001) in exercised (E), MOST-c treated (M) and their combination (ME) decreased significantly, while the dP/dt_max (p < 0.001, p < 0.001, p = 0.039) and dP/dt_min (p < 0.001, p < 0.001, p = 0.001) in groups E, M and ME were significantly higher than those in group C, but EDP (p = 0.903, p = 0.708, p = 0.744) remained unchanged. Moreover, C/EBPβ gene levels were significantly decreased in the differential gene expression between groups C and M transcriptomics sequencing. The levels of ErbB4 mRNA (p < 0.001, p < 0.001, p < 0.001) and Gata4 mRNA (p < 0.001, p < 0.001, p = 0.001) in groups E, M and ME increased significantly, while C/EBPβ mRNA expression decreased significantly (p < 0.001, p = 0.002, p = 0.001), which was consistent with the results of transcriptome sequencing. NRG1 mRNA in group E was significantly higher than that in group C (p = 0.003), but there was no significant difference between groups M and ME (p = 0.804, p = 0.320). The protein expression of NRG1 (p = 0.026, p < 0.001, p < 0.001), ErbB4 (p < 0.001, p < 0.001, p < 0.001) and Gata4 (p = 0.014, p < 0.001, p = 0.006) in groups E, M and ME increased significantly, while C/EBPβ decreased significantly (p < 0.001, p = 0.001, p = 0.002).

SIGNIFICANCE

Our findings suggest that MOTS-c and aerobic exercise had similar effects, improving myocardial morphology and structure and enhancing cardiac function through activation of the NRG1-ErbB4-C/EBPβ pathway.

Adipose tissue adipokines and lipokines: Functions and regulatory mechanism in skeletal muscle development and homeostasis

Skeletal muscle plays important roles in normal biological activities and whole-body energy homeostasis in humans. The growth and development of skeletal muscle also directly influence meat production and meat quality in animal production. Therefore, regulating the development and homeostasis of skeletal muscle is crucial for human health and animal production. Adipose tissue, which includes white adipose tissue (WAT) and brown adipose tissue (BAT), not only functions as an energy reserve but also has attracted substantial attention because of its role as an endocrine organ. The novel signalling molecules known as "adipokines" and "lipokines" that are secreted by adipose tissue were identified through the secretomic technique, which broadened our understanding of the previously unknown crosstalk between adipose tissue and skeletal muscle. In this review, we summarize and discuss the secretory role of adipose tissues, both WAT and BAT, as well as the regulatory roles of various adipokines and lipokines in skeletal muscle development and homeostasis. We suggest that adipokines and lipokines have potential as drug candidates for the treatment of skeletal muscle dysfunction and related metabolic diseases and as promising nutrients for improving animal production.

Neuregulin 4 as a novel adipokine in energy metabolism

Adipose tissue has been shown to play a key role in energy metabolism and it has been shown to regulate metabolic homeostasis through the secretion of adipokines. Neuregulin 4 (Nrg4), a novel adipokine secreted mainly by brown adipose tissue (BAT), has recently been characterized as having an important effect on the regulation of energy homeostasis and glucolipid metabolism. Nrg4 can modulate BAT-related thermogenesis by increasing sympathetic innervation of adipose tissue and therefore has potential metabolic benefits. Nrg4 improves metabolic dysregulation in various metabolic diseases such as insulin resistance, obesity, non-alcoholic fatty liver disease, and diabetes through several mechanisms such as anti-inflammation, autophagy regulation, pro-angiogenesis, and lipid metabolism normalization. However, inconsistent findings are found regarding the effects of Nrg4 on metabolic diseases in clinical settings, and this heterogeneity needs to be further clarified by future studies. The potential metabolic protective effect of Nrg4 suggests that it may be a promising endocrine therapeutic target.

Smad3 promotes adverse cardiovascular remodeling and dysfunction in doxorubicin-treated hearts

Many anticancer therapies cause serious cardiovascular complications that degrade quality of life and cause early mortality in treated patients. Specifically, doxorubicin is known as an effective anticancer agent that causes cardiomyopathy in treated patients. There has been growing interest in defining the role of endothelial cells in cardiac damage by doxorubicin. We have shown in the present study that endothelial nuclei accumulate more intravenously administered doxorubicin than other cardiac cell types. Doxorubicin enhanced cardiac production of the transforming growth factor-β (TGF-β) ligands and nuclear translocation of phospho-Smad3 in both cultured and in vivo cardiac endothelial cells. To examine the role of the TGF-β/mothers against decapentaplegic homolog 3 (Smad3) pathway in cardiac damage by doxorubicin, we used both Smad3 shRNA stable endothelial cell lines and Smad3-knockout mice. We demonstrated using endothelial transcriptome analysis that upregulation of the TGF-β and inflammatory cytokine/cytokine receptor pathways, as well as suppression of cell cycle and angiogenesis by doxorubicin, were alleviated in Smad3-deficient endothelial cells. The results of transcriptomic analysis were validated using qPCR, immunoblotting, and ex vivo aortic ring sprouting assays. Similarly, increased cardiac expression of cytokines and chemokines observed in treated wild-type mice was diminished in treated Smad3-knockout animals. We also detected increased end-diastolic diameter and depressed systolic function in doxorubicin-treated wild-type but not Smad3-knockout mice. This work provides evidence for the critical role of the canonical TGF-β/Smad3 pathway in cardiac damage by doxorubicin.NEW & NOTEWORTHY Microvascular endothelial cells in the heart accumulate more intravenously administered doxorubicin than nonendothelial cardiac cell types. The treatment enhanced the TGF-β/Smad3 pathway and elicited endothelial cell senescence and inflammatory responses followed by adverse cardiac remodeling and dysfunction in wild-type but not Smad3-deficient animals. Our study suggests that the TGF-β/Smad3 pathway contributes to the development of doxorubicin cardiomyopathy and the potential value of novel approaches to ameliorate cardiotoxicity by targeting the Smad3 transcription factor.

Beiging of perivascular adipose tissue regulates its inflammation and vascular remodeling

Although inflammation plays critical roles in the development of atherosclerosis, its regulatory mechanisms remain incompletely understood. Perivascular adipose tissue (PVAT) has been reported to undergo inflammatory changes in response to vascular injury. Here, we show that vascular injury induces the beiging (brown adipose tissue-like phenotype change) of PVAT, which fine-tunes inflammatory response and thus vascular remodeling as a protective mechanism. In a mouse model of endovascular injury, macrophages accumulate in PVAT, causing beiging phenotype change. Inhibition of PVAT beiging by genetically silencing PRDM16, a key regulator to beiging, exacerbates inflammation and vascular remodeling following injury. Conversely, activation of PVAT beiging attenuates inflammation and pathological vascular remodeling. Single-cell RNA sequencing reveals that beige adipocytes abundantly express neuregulin 4 (Nrg4) which critically regulate alternative macrophage activation. Importantly, significant beiging is observed in the diseased aortic PVAT in patients with acute aortic dissection. Taken together, vascular injury induces the beiging of adjacent PVAT with macrophage accumulation, where NRG4 secreted from the beige PVAT facilitates alternative activation of macrophages, leading to the resolution of vascular inflammation. Our study demonstrates the pivotal roles of PVAT in vascular inflammation and remodeling and will open a new avenue for treating atherosclerosis.

Perivascular adipose tissue (PVAT) has been reported to undergo inflammatory changes in response to vascular injury. Here, the authors show that vascular injury induces the beiging (brown adipose tissue-like phenotype change) of PVAT, which fine-tunes inflammatory response as a protective mechanism.

Identification of an Epigenetic Signature for Coronary Heart Disease in Postmenopausal Women’s PBMC DNA

Menopause is accompanied with an increased risk of cardiovascular disease. DNA methylation may have a significant impact on postmenopausal women's development of coronary heart disease. DNA methylation alterations in peripheral blood mononuclear cells (PBMCs) from women with coronary heart disease and healthy controls were detected using the Illumina Infinium MethylationEPIC BeadChip platform in this work. We employed Sangerbox technology and the GO and KEGG databases to further study the pathogenesis of coronary heart disease in postmenopausal women. After that, we used functional epigenetic module analysis and Cytoscape to remove the hub genes from the protein–protein interaction networks. Five genes (FOXA2, PTRD, CREB1, CTNAP2, and FBN2) were the hub genes. Lipid accumulation, endothelial cell failure, inflammatory responses, monocyte recruitment and aggregation, and other critical biological processes were all influenced by these genes. Finally, we employed methylation-specific PCR to demonstrate that FOXA2 was methylated at a high level in postmenopausal women with coronary heart disease. To better understand coronary heart disease in postmenopausal women's molecular mechanisms, our study examine the major factors contributing to the state of DNA methylation modification, which will help discover novel diagnostic tools and treatment options.

Neuregulin-1 signaling regulates cytokines and chemokines expression and secretion in granulosa cell

BACKGROUND

Granulosa cells (GCs) are multilayered somatic cells within the follicle that provide physical support and microenvironment for the developing oocyte. In recent years, the role of Neuregulin-1 (NRG1), a member of the EGF-like factor family, has received considerable attention due to its neurodevelopmental and cardiac function. However, the exact physiological role of NRG1 in GC is mainly unknown. In order to confirm that NRG1 plays a regulatory role in rat GC functions, endogenous NRG1-knockdown studies were carried out in GCs using RNA interference methodology.

RESULTS

Knockdown of NRG1 in GCs resulted in the enhanced expression and secretion of the cytokines and chemokines. In addition, the phosphorylation of PI3K/Akt/ERK1/2 was significantly low in GCs under these experimental conditions. Moreover, in vitro experimental studies suggest that tumor necrosis factor-α (TNFα) treatment causes the physical destruction of GCs by activating caspase-3/7 activity. In contrast, exogenous NRG1 co-treatment of GCs delayed the onset of TNFα-induced apoptosis and inhibited the activation of caspase-3/7 activity. Furthermore, current experimental studies suggest that gonadotropins promote differential expression of NRG1 and ErbB3 receptors in GCs of the antral follicle. Interestingly, NRG1 and ErbB3 were intensely co-localized in the mural and cumulus GCs and cumulus-oocyte complex of pre-ovulatory follicles in the estrus stage.

CONCLUSIONS

The present studies suggest that gonadotropins-dependent NRG1-signaling in GCs may require the balance of the cytokines and chemokines expression and secretion, ultimately which may be supporting the follicular maturation and oocyte competence for ovulation and preventing follicular atresia.

Mechanisms of Cardiorenal Protection With SGLT2 Inhibitors in Patients With T2DM Based on Network Pharmacology

Purpose

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have cardiorenal protective effects regardless of whether they are combined with type 2 diabetes mellitus, but their specific pharmacological mechanisms remain undetermined.

Materials and Methods

We used databases to obtain information on the disease targets of “Chronic Kidney Disease,” “Heart Failure,” and “Type 2 Diabetes Mellitus” as well as the targets of SGLT2 inhibitors. After screening the common targets, we used Cytoscape 3.8.2 software to construct SGLT2 inhibitors' regulatory network and protein-protein interaction network. The clusterProfiler R package was used to perform gene ontology functional analysis and Kyoto encyclopedia of genes and genomes pathway enrichment analyses on the target genes. Molecular docking was utilized to verify the relationship between SGLT2 inhibitors and core targets.

Results

Seven different SGLT2 inhibitors were found to have cardiorenal protective effects on 146 targets. The main mechanisms of action may be associated with lipid and atherosclerosis, MAPK signaling pathway, Rap1 signaling pathway, endocrine resistance, fluid shear stress, atherosclerosis, TNF signaling pathway, relaxin signaling pathway, neurotrophin signaling pathway, and AGEs-RAGE signaling pathway in diabetic complications were related. Docking of SGLT2 inhibitors with key targets such as GAPDH, MAPK3, MMP9, MAPK1, and NRAS revealed that these compounds bind to proteins spontaneously.

Conclusion

Based on pharmacological networks, this study elucidates the potential mechanisms of action of SGLT2 inhibitors from a systemic and holistic perspective. These key targets and pathways will provide new ideas for future studies on the pharmacological mechanisms of cardiorenal protection by SGLT2 inhibitors.

Protective Effect of Curcumin, Chrysin and Thymoquinone Injection on Trastuzumab-Induced Cardiotoxicity via Mitochondrial Protection

Mitochondrial dysfunction may lead to cardiomyocyte death in trastuzumab (TZM)-induced cardiotoxicity. Accordingly, this study was designed to evaluate the mitochondrial protective effects of curcumin, chrysin and thymoquinone alone in TZM-induced cardiotoxicity in the rats. Forty-eight male adult Wistar rats were divided into eight groups: control group (normal saline), TZM group (2.5 mg/kg I.P. injection, daily), TZM + curcumin group (10 mg/kg, I.P. injection, daily), TZM + chrysin (10 mg/kg, I.P. injection, daily), TZM + thymoquinone (0.5 mg/kg, I.P. injection, daily), curcumin group (10 mg/kg, I.P. injection, daily), chrysin group (10 mg/kg, I.P. injection, daily) and thymoquinone group (10 mg/kg, I.P. injection, daily). Blood and tissue were collected on day 11 and used for assessment of creatine phosphokinase, lactate dehydrogenase (LDH), troponin, malondialdehyde (MDA) amount, glutathione levels and mitochondrial toxicity parameters. TZM increased mitochondrial impairments (reactive oxygen species formation, mitochondrial swelling, mitochondrial membrane potential collapse and decline in succinate dehydrogenase activity) and histopathological alterations (hypertrophy, enlarged cell, disarrangement, myocytes degeneration, infiltration of fat in some areas, hemorrhage and focal vascular thrombosis) in rat heart. As well as TZM produced a significant increase in the level of CK, LDH, troponin, MDA, glutathione disulfide. In most experiments, the co-injection of curcumin, chrysin and thymoquinone with TZM restored the level of CK, LDH, troponin, MDA, GSH, mitochondrial impairments and histopathological alterations. The study revealed the cardioprotective effects of curcumin, chrysin and thymoquinone against TZM-induced cardiotoxicity which could be attributed to their antioxidant and mitochondrial protection activities.

A new strategy for stem cells therapy for erectile dysfunction: Adipose-derived stem cells transfect Neuregulin-1 gene through superparamagnetic iron oxide nanoparticles

PURPOSE

Our previous studies showed that nanotechnology improves derived adipose-derived stem cells (ADSCs) therapy for erectile dysfunction (ED). In this study, the Neuregulin-1(NRG1) gene was transfected into ADSCs with superparamagnetic iron oxide nanoparticles (SPION) further to improve the therapeutic effect of ADSCs on ED.

MATERIALS AND METHODS

ADSCs were isolated from epididymal adipose tissue of Sprague-Dawley rats. The optimal concentration of PEI-SPION (SPION modified with polyethyleneimine) was selected to construct the gene complex. After electrostatic binding of PEI-SPION and DNA, a PEI layer was wrapped to make the PEI-SPION-NRG1-PEI gene transfection complex. Different groups were set up for transfection tests. Lipo2000 transfection reagent was used as the control. PEI-SPION-NRG1-PEI in the experimental group was transfected under an external magnetic field.

RESULTS

When the concentration of PEI-SPION was 10 µg/mL, it had little cytotoxicity, and cell activity was not significantly affected. PEI-SPION-NRG1-PEI forms positively charged nanocomposites with a particle size of 72.6±14.9 nm when N/P ≥8. The PEI-SPION-NRG1-PEI gene complex can significantly improve the transfection efficiency of ADSCs, reaching 26.74%±4.62%, under the action of the external magnetic field. PCR and Western blot showed that the expression level of the NRG1 gene increased significantly, which proved that the transfection was effective.

CONCLUSIONS

PEI-SPION can be used as a vector for NRG1 gene transfection into ADSCs. PEI-SPION-NRG1-PEI packaging has the highest transfection efficiency under the external magnetic field than the other groups. These findings may provide a new strategy for ADSCs therapy for ED.

Decreased expression of ErbB2 on left ventricular epicardial cells in patients with diabetes mellitus

We investigated the cell surface expression of ErbB receptors on left ventricular (LV) epicardial endothelial cells and CD105⁺ cells obtained from cardiac biopsies of patients undergoing coronary artery bypass grafting surgery (CABG). Endothelial cells and CD105⁺ non-endothelial cells were freshly isolated from LV epicardial biopsies obtained from 15 subjects with diabetes mellitus (DM) and 8 controls. The expression of ErbB receptors was examined using flow cytometry. We found that diabetes mellitus (DM) and high levels of hemoglobin A1C are associated with reduced expression of ErbB2. To determine if the expression of ErbB2 receptors is regulated by glucose levels, we examined the effect of high Glucose in human microvascular endothelial cells (HMEC-1) and CD105⁺ non-endothelial cells, using a novel flow cytometric approach to simultaneously determine the total level, cell surface expression, and phosphorylation of ErbB2. Incubation of cells in the presence of 25 mM d-glucose resulted in decreased cell surface but not total levels of ErbB2. The level of ErbB2 at the cell surface is controlled by disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) that is expressed on LV epicardial cells. Inhibition of ADAM10 prevented the high glucose-dependent decrease in the cell surface expression of ErbB2. We suggest that high Glucose depresses ErbB receptor signaling in endothelial cells and cardiac progenitor cells via the promotion of ADAM10-dependent cleavage of ErbB2 at the cell surface, thus contributing to vascular dysfunction and adverse remodeling seen in diabetic patients.

The Research Progress of Trastuzumab-Induced Cardiotoxicity in HER-2-Positive Breast Cancer Treatment

In recent years, the incidence of breast cancer has been increasing on an annual basis. Human epidermal growth factor receptor-2 (HER-2) is overexpressed in 15-20% human breast cancers, which is associated with poor prognosis and a high recurrence rate. Trastuzumab is the first humanized monoclonal antibody against HER-2. The most significant adverse effect of trastuzumab is cardiotoxicity, which has become an important factor in limiting the safe use of the drug. Unfortunately, the mechanism causing this cardiotoxicity is still not completely understood, and the use of preventive interventions remains controversial. This article focuses on trastuzumab-induced cardiotoxicity, reviewing the clinical application, potential cardiotoxicity, mechanism and discussing the potential interventions through summarizing related researches over the past tens of years.

Neuregulin 1 Drives Morphological and Phenotypical Changes in C2C12 Myotubes: Towards De Novo Formation of Intrafusal Fibres In Vitro

Muscle spindles are sensory organs that detect and mediate both static and dynamic muscle stretch and monitor muscle position, through a specialised cell population, termed intrafusal fibres. It is these fibres that provide a key contribution to proprioception and muscle spindle dysfunction is associated with multiple neuromuscular diseases, aging and nerve injuries. To date, there are few publications focussed on de novo generation and characterisation of intrafusal muscle fibres in vitro. To this end, current models of skeletal muscle focus on extrafusal fibres and lack an appreciation for the afferent functions of the muscle spindle. The goal of this study was to produce and define intrafusal bag and chain myotubes from differentiated C2C12 myoblasts, utilising the addition of the developmentally associated protein, Neuregulin 1 (Nrg-1). Intrafusal bag myotubes have a fusiform shape and were assigned using statistical morphological parameters. The model was further validated using immunofluorescent microscopy and western blot analysis, directed against an extensive list of putative intrafusal specific markers, as identified in vivo. The addition of Nrg-1 treatment resulted in a 5-fold increase in intrafusal bag myotubes (as assessed by morphology) and increased protein and gene expression of the intrafusal specific transcription factor, Egr3. Surprisingly, Nrg-1 treated myotubes had significantly reduced gene and protein expression of many intrafusal specific markers and showed no specificity towards intrafusal bag morphology. Another novel finding highlights a proliferative effect for Nrg-1 during the serum starvation-initiated differentiation phase, leading to increased nuclei counts, paired with less myotube area per myonuclei. Therefore, despite no clear collective evidence for specific intrafusal development, Nrg-1 treated myotubes share two inherent characteristics of intrafusal fibres, which contain increased satellite cell numbers and smaller myonuclear domains compared with their extrafusal neighbours. This research represents a minimalistic, monocellular C2C12 model for progression towards de novo intrafusal skeletal muscle generation, with the most extensive characterisation to date. Integration of intrafusal myotubes, characteristic of native, in vivo intrafusal skeletal muscle into future biomimetic tissue engineered models could provide platforms for developmental or disease state studies, pre-clinical screening, or clinical applications.

The Potential of Gamma Secretase as a Therapeutic Target for Cardiac Diseases

Heart diseases are some of the most common and pressing threats to human health worldwide. The American Heart Association and the National Institute of Health jointly work to annually update data on cardiac diseases. In 2018, 126.9 million Americans were reported as having some form of cardiac disorder, with an estimated direct and indirect total cost of USD 363.4 billion. This necessitates developing therapeutic interventions for heart diseases to improve human life expectancy and economic relief. In this review, we look into gamma-secretase as a potential therapeutic target for cardiac diseases. Gamma-secretase, an aspartyl protease enzyme, is responsible for the cleavage and activation of a number of substrates that are relevant to normal cardiac development and function as found in mutation studies. Some of these substrates are involved in downstream signaling processes and crosstalk with pathways relevant to heart diseases. Most of the substrates and signaling events we explored were found to be potentially beneficial to maintain cardiac function in diseased conditions. This review presents an updated overview of the current knowledge on gamma-secretase processing of cardiac-relevant substrates and seeks to understand if the modulation of gamma-secretase activity would be beneficial to combat cardiac diseases.

Epitranscriptomics of Ischemic Heart Disease-The IHD-EPITRAN Study Design and Objectives

Epitranscriptomic modifications in RNA can dramatically alter the way our genetic code is deciphered. Cells utilize these modifications not only to maintain physiological processes, but also to respond to extracellular cues and various stressors. Most often, adenosine residues in RNA are targeted, and result in modifications including methylation and deamination. Such modified residues as N-6-methyl-adenosine (m6A) and inosine, respectively, have been associated with cardiovascular diseases, and contribute to disease pathologies. The Ischemic Heart Disease Epitranscriptomics and Biomarkers (IHD-EPITRAN) study aims to provide a more comprehensive understanding to their nature and role in cardiovascular pathology. The study hypothesis is that pathological features of IHD are mirrored in the blood epitranscriptome. The IHD-EPITRAN study focuses on m6A and A-to-I modifications of RNA. Patients are recruited from four cohorts: (I) patients with IHD and myocardial infarction undergoing urgent revascularization; (II) patients with stable IHD undergoing coronary artery bypass grafting; (III) controls without coronary obstructions undergoing valve replacement due to aortic stenosis and (IV) controls with healthy coronaries verified by computed tomography. The abundance and distribution of m6A and A-to-I modifications in blood RNA are charted by quantitative and qualitative methods. Selected other modified nucleosides as well as IHD candidate protein and metabolic biomarkers are measured for reference. The results of the IHD-EPITRAN study can be expected to enable identification of epitranscriptomic IHD biomarker candidates and potential drug targets.

The Impact of Spaceflight and Microgravity on the Human Islet-1+ Cardiovascular Progenitor Cell Transcriptome

Understanding the transcriptomic impact of microgravity and the spaceflight environment is relevant for future missions in space and microgravity-based applications designed to benefit life on Earth. Here, we investigated the transcriptome of adult and neonatal cardiovascular progenitors following culture aboard the International Space Station for 30 days and compared it to the transcriptome of clonally identical cells cultured on Earth. Cardiovascular progenitors acquire a gene expression profile representative of an early-stage, dedifferentiated, stem-like state, regardless of age. Signaling pathways that support cell proliferation and survival were induced by spaceflight along with transcripts related to cell cycle re-entry, cardiovascular development, and oxidative stress. These findings contribute new insight into the multifaceted influence of reduced gravitational environments.