Over-expression of JAZF1 promotes cardiac microvascular endothelial cell proliferation and angiogenesis via activation of the Akt signaling pathway in rats with myocardial ischemia-reperfusion

Potential cardiac-derived exosomal miRNAs involved in cardiac healing and remodeling after myocardial ischemia-reperfusion injury

Migratory cells exist in the heart, such as immune cells, fibroblasts, endothelial cells, etc. During myocardium injury, such as ischemia-reperfusion (MIRI), cells migrate to the site of injury to perform repair functions. However, excessive aggregation of these cells may exacerbate damage to the structure and function of the heart, such as acute myocarditis and myocardial fibrosis. Myocardial injury releases exosomes, which are a type of vesicle with signal transduction function and the miRNA carried by exosomes can control cell migration function. Therefore, regulating this migratory cell population through cardiac-derived exosomal miRNA is crucial for protecting and maintaining cardiac function. Through whole transcriptome RNA sequencing, exosomal miRNA sequencing and single-cell dataset analysis, we (1) determined the potential molecular regulatory role of the lncRNA‒miRNA‒mRNA axis in MIRI, (2) screened four important exosomal miRNAs that could be released by cardiac tissue, and (3) screened seven genes related to cell locomotion that are regulated by four miRNAs, among which Tradd and Ephb6 may be specific for promoting migration of different cells of myocardial tissue in myocardial infarct. We generated a core miRNA‒mRNA network based on the functions of the target genes, which may be not only a target for cardiac repair but also a potential diagnostic marker for interactions between the heart and other tissues or organs. In conclusion, we elucidated the potential mechanism of MIRI in cardiac remodeling from the perspective of cell migration, and inhibition of cellular overmigration based on this network may provide new therapeutic targets for MIRI and to prevent MIRI from developing into other diseases.

CD226 implicated in Akt-dependent apoptosis of CD4+ T cell contributes to asthmatic pathogenesis

Asthma is a chronic airway inflammatory disease in which CD4+ T cell dysregulation occurs. Here, we investigated the molecular role and clinical significance of CD226, a costimulatory molecule of T lymphocytes, in the development of allergic asthma. Our results revealed that the expression of CD226 was significantly increased in CD4+ effector T cells, especially in T helper (Th) 2 cells and Th17 cells in patients with asthma. Moreover, CD4+ T cell-specific Cd226-knockout mice were generated and together with littermates were challenged with ovalbumin (OVA) to establish a model of allergic asthma. We found that CD226 deficiency in CD4+ T cells mitigated lung inflammation, IgE production, and eosinophil infiltration and reduced airway remodeling in experimental allergic asthma. However, the impact of CD226 on asthma was independent of Treg cell modulation. Through RNA-seq data analysis, the apoptosis pathway was screened. Mechanistically, CD226 deletion promoted CD4+ T cell late apoptosis via the activation of Caspase-3 in an Akt-dependent manner. Furthermore, blocking CD226 signaling with a recombinant fusion protein attenuated asthma features in mice and achieved a good therapeutic effect. Overall, this study revealed a unique role of CD226 in CD4+ T cell regulation in asthma pathogenesis. Therefore, targeting CD226 may provide new insights into the clinical treatment of asthma.

Whole-genome resequencing of Chinese indigenous sheep provides insight into the genetic basis underlying climate adaptation

BACKGROUND

Chinese indigenous sheep are valuable resources with unique features and characteristics. They are distributed across regions with different climates in mainland China; however, few reports have analyzed the environmental adaptability of sheep based on their genome. We examined the variants and signatures of selection involved in adaptation to extreme humidity, altitude, and temperature conditions in 173 sheep genomes from 41 phenotypically and geographically representative Chinese indigenous sheep breeds to characterize the genetic basis underlying environmental adaptation in these populations.

RESULTS

Based on the analysis of population structure, we inferred that Chinese indigenous sheep are divided into four groups: Kazakh (KAZ), Mongolian (MON), Tibetan (TIB), and Yunnan (YUN). We also detected a set of candidate genes that are relevant to adaptation to extreme environmental conditions, such as drought-prone regions (TBXT, TG, and HOXA1), high-altitude regions (DYSF, EPAS1, JAZF1, PDGFD, and NF1) and warm-temperature regions (TSHR, ABCD4, and TEX11). Among all these candidate genes, eight ABCD4, CNTN4, DOCK10, LOC105608545, LOC121816479, SEM3A, SVIL, and TSHR overlap between extreme environmental conditions. The TSHR gene shows a strong signature for positive selection in the warm-temperature group and harbors a single nucleotide polymorphism (SNP) missense mutation located between positions 90,600,001 and 90,650,001 on chromosome 7, which leads to a change in the protein structure of TSHR and influences its stability.

CONCLUSIONS

Analysis of the signatures of selection uncovered genes that are likely related to environmental adaptation and a SNP missense mutation in the TSHR gene that affects the protein structure and stability. It also provides information on the evolution of the phylogeographic structure of Chinese indigenous sheep populations. These results provide important genetic resources for future breeding studies and new perspectives on how animals can adapt to climate change.

New insights into the suppression of inflammation and lipid accumulation by JAZF1

Atherosclerosis is one of the leading causes of disease and death worldwide. The identification of new therapeutic targets and agents is critical. JAZF1 is expressed in many tissues and is found at particularly high levels in adipose tissue (AT). JAZF1 suppresses inflammation (including IL-1β, IL-4, IL-6, IL-8, IL-10, TNFα, IFN-γ, IAR-20, COL3A1, laminin, and MCP-1) by reducing NF-κB pathway activation and AT immune cell infiltration. JAZF1 reduces lipid accumulation by regulating the liver X receptor response element (LXRE) of the SREBP-1c promoter, the cAMP-response element (CRE) of HMGCR, and the TR4 axis. LXRE and CRE sites are present in many cytokine and lipid metabolism gene promoters, which suggests that JAZF1 regulates these genes through these sites. NF-κB is the center of the JAZF1-mediated inhibition of the inflammatory response. JAZF1 suppresses NF-κB expression by suppressing TAK1 expression. Interestingly, TAK1 inhibition also decreases lipid accumulation. A dual-targeting strategy of NF-κB and TAK1 could inhibit both inflammation and lipid accumulation. Dual-target compounds (including prodrugs) 1-5 exhibit nanomolar inhibition by targeting NF-κB and TAK1, EGFR, or COX-2. However, the NF-κB suppressing activity of these compounds is relatively low (IC50 > 300 nM). Compounds 6-14 suppress NF-κB expression with IC50 values ranging from 1.8 nM to 38.6 nM. HS-276 is a highly selective, orally bioavailable TAK1 inhibitor. Combined structural modifications of compounds using a prodrug strategy may enhance NF-κB inhibition. This review focused on the role and mechanism of JAZF1 in inflammation and lipid accumulation for the identification of new anti-atherosclerotic targets.

JAZF1 safeguards human endometrial stromal cells survival and decidualization by repressing the transcription of G0S2

Decidualization of human endometrial stromal cells (hESCs) is essential for the maintenance of pregnancy, which depends on the fine-tuned regulation of hESCs survival, and its perturbation contributes to pregnancy loss. However, the underlying mechanisms responsible for functional deficits in decidua from recurrent spontaneous abortion (RSA) patients have not been elucidated. Here, we observed that JAZF1 was significantly downregulated in stromal cells from RSA decidua. JAZF1 depletion in hESCs resulted in defective decidualization and cell death through apoptosis. Further experiments uncovered G0S2 as a important driver of hESCs apoptosis and decidualization, whose transcription was repressed by JAZF1 via interaction with G0S2 activator Purβ. Moreover, the pattern of low JAZF1, high G0S2 and excessive apoptosis in decidua were consistently observed in RSA patients. Collectively, our findings demonstrate that JAZF1 governs hESCs survival and decidualization by repressing G0S2 transcription via restricting the activity of Purβ, and highlight the clinical implications of these mechanisms in the pathology of RSA.

ZNF667 facilitates angiogenesis after myocardial ischemia through transcriptional regulation of VASH1 and Wnt signaling pathway

Zinc finger protein 667 (ZNF667, also referred as Mipu1), a widely expressed KRAB/C₂H₂-type zinc finger transcription factor, can protect against hypoxic-ischemic myocardial injury. Pro-angiogenesis is regarded as a promising strategy for the treatment of acute myocardial infarction (AMI). However, whether ZNF667 is involved in the angiogenesis following AMI remains to be elucidated. The present study reported that the expression of ZNF667 in CD31-positive endothelial cells (ECs) was upregulated in the heart of AMI mice. Hypoxic challenge (1% oxygen) promoted the mRNA and protein expression of ZNF667 in the human umbilical vein endothelial cells (HUVECs) in a time-dependent manner. Moreover, ZNF667 promoted hypoxia-induced invasion and tube formation of HUVECs. Mechanically, ZNF667 could directly bind to the promoter of anti-angiogenic gene VASH1 and inhibit its expression. Consequently, VASH1 overexpression abolished hypoxic challenge or ZNF667 overexpression-induced invasion and tube formation of HUVECs. Further bioinformatic analyses suggested that overexpression of ZNF667 or knockdown of VASH1-induced differentially expressed genes in HUVECs were greatly enriched in the Wnt signaling pathway (DAAM1, LEF1, RAC2, FRAT1, NFATc2 and WNT5A). Together, these data suggested that ZNF667 facilitates myocardial ischemia-driven angiogenesis through transcriptional repression of VASH1 and regulation of Wnt signaling pathway.

Roles of isometric contraction training in promoting neuroprotection and angiogenesis after stroke in adult rats

100 rats were randomly divided into a sham-operated group and middle cerebral artery occlusion (MCAO) modeling groups. The sham group after surgery was observed for 14 days. After MCAO, some rats received isometric contraction training (ICT) which was as follows: an atraumatic tourniquet was placed around left or right hind limb to achieve hind limb ischemia for 5 min, followed by 5 min of reperfusion, 4 cycles for one time, once a day, and five days per week. The MCAO modeling groups included the following four groups: i) a group only received MCAO, and was observed for seven days (MCAO-7d), ii) a group only received MCAO, and was observed for 14 days (MCAO-14d), iii) a group, after MCAO, received ICT for seven days (ICT-7d), and iv) a group, after MCAO, received ICT for 14 days (ICT-14d). Brain infarct area, behavioral outcomes, the number of neurons, apoptosis, cerebral edema and cerebral water content were assessed, respectively. The mRNA expression of vascular endothelial growth factor (VEGF) was assayed with RT-PCR, and protein expression of VEGF was quantified with western blot. compared with MCAO controls, cerebral infarction, neurological deficits and neuronal apoptosis were reduced significantly in the ICT groups, while the number of neurons was increased. Moreover, the mRNA expression of VEGF and protein expression of VEGF were enhanced after 1 and 2 weeks of ICT. ICT may promote angiogenesis and neuroprotection after ischemic stroke and this new remodeling method provide a novel strategy for rehabilitation of stroke patients.

Oxycodone protects cardiac microvascular endothelial cells against ischemia/reperfusion injury by binding to Sigma-1 Receptor

Endothelial dysfunction is an important mechanism involved in myocardial ischemia-reperfusion (I/R) injury. We aimed to explore the effects of Oxycodone on myocardial I/R injury in vivo and in vitro to reveal its mechanisms related to Sigma-1 Receptor (SIGMAR1). A rat model of I/R-induced myocardial injury was developed. The ischemic area and myocardial histopathological changes after oxycodone addition were evaluated by TTC staining and H&E staining. LDH, CK-MB and cTnI levels were used to assess myocardial function. Then, the endothelial integrity was reflected by the expressions of ZO-1, Claudin-1 and Occludin. Afterward, ELISA, RT-qPCR, western blot and immunofluorescence assays were adopted for the detection of inflammation-related genes. SIGMAR1 expression in myocardial tissues induced by I/R and cardiac microvascular endothelial cells (CMECs) under hypoxic/reoxygenation (H/R) was determined using RT-qPCR and western blotting. Subsequently, after SIGMAR1 silencing or BD1047 addition (a SIGMAR1 antagonist), cell apoptosis and endothelial integrity were analyzed in the presence of Oxycodone in H/R-stimulated CMECs. Results indicated that Oxycodone decreased the ischemic area and improved myocardial function in myocardial I/R injury rat. Oxycodone improved myocardial histopathological injury and elevated endothelial integrity, evidenced by upregulated ZO-1, Claudin-1 and Occludin expressions. Moreover, inflammatory response was alleviated after Oxycodone administration. Molecular docking suggested that SIGMAR1 could directly bind to Oxycodone. Oxycodone elevated SIGMAR1 expression and SIGMAR1 deletion or BD1047 addition attenuated the impacts of Oxycodone on apoptosis and endothelial integrity of CMECs induced by H/R. Collectively, Oxycodone alleviates myocardial I/R injury in vivo and in vitro by binding to SIGMAR1.

Preparation of a JAZF1 protein polyclonal antibody and its potential role in broiler ascites syndrome

As a novel functional protein, juxtaposed with another zinc finger protein 1 (JAZF1) can regulate the growth and apoptosis through various pathways, and maintain the body's normal physiological metabolism. To explore the important role of JAZF1 in broiler ascites syndrome (BAS), we analysed the expression and distribution of the protein in poultry and mammal tissues based on the prepared polyclonal antibody. In this study, the recombinant plasmid PET32a-JAZF1 was constructed by TA cloning, subcloning and other technical methods, and the fusion protein His-JAZF1 was successfully expressed. After purification, His-JAZF1 was used as the antigen to prepare high-quality chicken-derived antibodies. Subsequently, the results showed that JAZF1 protein in broiler tissues could be specifically recognized by this antibody. Immunofluorescence showed that JAZF1 protein mainly exists in the cytoplasm of pulmonary artery, liver, kidney, heart and lung tissue cells of various animals. The expression of this protein was more obvious in broiler and duck tissues than in mammalian tissues. In addition, western blotting combined with immunofluorescence showed that BAS caused a significant decrease in JAZF1 protein in tissue cells. This effect further indicated that JAZF1 protein was closely related to the occurrence of BAS and provided a new entry point for the functional study of JAZF1 protein.

E3 ubiquitin ligase mind bomb 1 overexpression reduces apoptosis and inflammation of cardiac microvascular endothelial cells in coronary microvascular dysfunction

BACKGROUND

The apoptosis and inflammation in cardiac microvascular endothelial cells (CMECs) promote the development of coronary microvascular dysfunction (CMD). The present study aimed to explore the role of E3 ubiquitin ligase mind bomb 1 (MIB1) in the apoptosis and inflammation in CMECs during CMD.

METHODS

In vivo, CMD in rats was induced by sodium laurate injection. In vitro, rat primary CMECs were stimulated by homocysteine (Hcy). The apoptosis of CMECs was measured using flow cytometry. The inflammation of CMECs was evaluated by the level of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β). The interplay between MIB1 and mitogen-activated protein kinase kinase kinase 5 (map3k5, also called ASK1) was measured using Co-immunoprecipitation.

RESULTS

MIB1 expression was decreased and ASK1 expression was increased in the heart tissues of CMD rats and Hcy-treated CMECs. MIB1 overexpression decreased fibrinogen-like protein 2 (FGL2) secretion, inflammation, and apoptosis induced by Hcy in CMECs. Meanwhile, MIB1 overexpression decreased the protein levels of ASK1 and p38, while not affected ASK1 mRNA levels. The following mechanism experiments revealed that MIB1 downregulated ASK1 expression by increasing its ubiquitination. ASK1 overexpression reversed the inhibitory effect of MIB1 on FGL2 secretion, apoptosis, inflammation, and p38 activation in Hcy-treated CMECs. In CMD rats, MIB1 overexpression partly retarded CMD progression, manifesting as increased coronary capillary density and decreased microthrombi formation.

CONCLUSION

MIB1 overexpression relieved apoptosis and inflammation of CMECs during CMD by targeting the ASK1/p38 pathway.

Improvement of tube formation model of cell: Application for acute hypoxia in in vitro study of angiogenesis

Angiogenesis caused by acute vascular occlusion occurs in various ischemic diseases. The in vitro tube formation assay by endothelial cells is a rapid, quantitative method for drug discovery on angiogenesis. Tube formation assay on Matrigel has been widely used to identify the angiogenesis, however, there are some problems to limit its application. In this study, we found for the first time that sodium dithionite (SD) could induce endothelial cell tube formation without Matrigel under hypoxia condition. To further verify our findings, the angiogenesis related proteins and mRNA at different time points after tube formation were measured both in primary human large-vessel endothelial cell (HUVECs) and murine microvascular endothelial cell line (Bend.3). In conclusion, compared with traditional tube formation on Matrigel, the novel model exhibits the following advantages: (1) Combination oxygen glucose deprivation with sodium dithionite (OGD-SD) model is operated more easily than traditional tube formation. (2) OGD-SD can be used for not only cell imaging, but also immunofluorescence, protein extraction and gene analysis. (3) OGD-SD is more applicable to acute hypoxia model of endothelial cell in vitro. (4) OGD-SD may be more suitable to identify molecular mechanism of compound that intervenes processes of pro-tube formation, tube formation and tube disconnection.

Crosstalk between circRNAs and the PI3K/AKT signaling pathway in cancer progression

Circular RNAs (circRNAs), covalently closed noncoding RNAs, are widely expressed in eukaryotes and viruses. They can function by regulating target gene expression, linear RNA transcription and protein generation. The phosphoinositide 3-kinase (PI3K)/AKT signaling pathway plays key roles in many biological and cellular processes, such as cell proliferation, growth, invasion, migration, and angiogenesis. It also plays a pivotal role in cancer progression. Emerging data suggest that the circRNA/PI3K/AKT axis modulates the expression of cancer-associated genes and thus regulates tumor progression. Aberrant regulation of the expression of circRNAs in the circRNA/PI3K/AKT axis is significantly associated with clinicopathological characteristics and plays an important role in the regulation of biological functions. In this review, we summarized the expression and biological functions of PI3K-AKT-related circRNAs in vitro and in vivo and assessed their associations with clinicopathological characteristics. We also further discussed the important role of circRNAs in the diagnosis, prognostication, and treatment of cancers.

Remifentanil pretreatment ameliorates H/R-induced cardiac microvascular endothelial cell dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway

Restoration of blood supply through medical or surgical intervention is a commonly adopted method for acute myocardial ischemia, but is also a trigger for cardiac ischemia/reperfusion injury. Studies have shown that remifentanil (REM) displays cardioprotective effects. In this study, the effects of REM on HCMEC viability were examined before and after the induction of H/R using Cell Counting Kit-8 assays. Wound healing and Matrigel angiogenesis assays were performed to assess HCMEC migration and angiogenesis, respectively. Commercial kits and western blotting were used to determine the endothelial barrier function of H/R-stimulated HCMECs with or without REM treatment. The expression of PI3K/Akt/hypoxia-inducible factor-1α (HIF-1α) pathway-related proteins was detected by western blotting. After pre-treatment with PI3K/Akt, the effects of REM on H/R-induced HCMEC injury were examined. We found that pre-treatment with REM displayed no impact on HCMEC viability under normal conditions but noticeably improved cell viability following H/R. The migratory abilities and tube-like structure formations of H/R-stimulated HCMECs were both enhanced by REM in a concentration-dependent manner. REM also decreased the permeability of H/R-stimulated HCMECs and upregulated the expression of tight junction proteins. Furthermore REM increased the expression of PI3K/Akt/HIF-1α signaling-related proteins in HCMECs. Inhibition of PI3K/Akt rescued REM-enhanced HCMEC function under H/R condition. Therefore, the present study demonstrated that REM pretreatment ameliorated H/R-induced HCMEC dysfunction by regulating the PI3K/Akt/HIF-1α signaling pathway.

Jazf1 acts as a regulator of insulin-producing β-cell differentiation in induced pluripotent stem cells and glucose homeostasis in mice

Genetic susceptibility of type 2 diabetes and Juxtaposed with another zinc finger protein 1 (Jazf1) has been reported; however, the precise role of Jazf1 in metabolic processes remains elusive. In this study, using Jazf1-knockout (KO)-induced pluripotent stem cells (iPSC), pancreatic beta cell line MIN6 cells, and Jazf-1 heterozygous KO (Jazf1^+/- ) mice, the effect of Jazf1 on gradual differentiation was investigated. We checked the alterations of the genes related with β-cell specification, maturation, and insulin release against glucose treatment by the gain and loss of the Jazf1 gene in the MIN6 cells. Because undifferentiated Jazf1-KO iPSC were not significantly different from wild-type (WT) iPSC, the size and endoderm marker expression after embryoid body (EB) and teratoma formation were investigated. Compared to EB and teratomas formed with WT iPSC, the EB and teratomas from with Jazf1-KO iPSC were smaller, and in teratomas, the expression of proliferation markers was reduced. Moreover, the expression of the gene sets for β-cell differentiation and the levels of insulin and C-peptide secreted by insulin precursor cells were notably reduced in β-cells differentiated from Jazf1-KO iPSC compared with those differentiated from WT iPSC. A comparison of Jazf1^+/- and WT mice showed that Jazf1^+/- mice had lower levels of serum insulin, pancreatic insulin expression, and decreased pancreatic β-cell size, which resulted in defects in the glucose homeostasis. These findings suggest that Jazf1 plays a pivotal role in the differentiation of β-cells and glucose homeostasis.

DNA methylation and gene expression integration in cardiovascular disease

BACKGROUND

The integration of different layers of omics information is an opportunity to tackle the complexity of cardiovascular diseases (CVD) and to identify new predictive biomarkers and potential therapeutic targets. Our aim was to integrate DNA methylation and gene expression data in an effort to identify biomarkers related to cardiovascular disease risk in a community-based population. We accessed data from the Framingham Offspring Study, a cohort study with data on DNA methylation (Infinium HumanMethylation450 BeadChip; Illumina) and gene expression (Human Exon 1.0 ST Array; Affymetrix). Using the MOFA2 R package, we integrated these data to identify biomarkers related to the risk of presenting a cardiovascular event.

RESULTS

Four independent latent factors (9, 19, 21-only in women-and 27), driven by DNA methylation, were associated with cardiovascular disease independently of classical risk factors and cell-type counts. In a sensitivity analysis, we also identified factor 21 as associated with CVD in women. Factors 9, 21 and 27 were also associated with coronary heart disease risk. Moreover, in a replication effort in an independent study three of the genes included in factor 27 were also present in a factor identified to be associated with myocardial infarction (CDC42BPB, MAN2A2 and RPTOR). Factor 9 was related to age and cell-type proportions; factor 19 was related to age and B cells count; factor 21 pointed to human immunodeficiency virus infection-related pathways and inflammation; and factor 27 was related to lifestyle factors such as alcohol consumption, smoking and body mass index. Inclusion of factor 21 (only in women) improved the discriminative and reclassification capacity of the Framingham classical risk function and factor 27 improved its discrimination.

CONCLUSIONS

Unsupervised multi-omics data integration methods have the potential to provide insights into the pathogenesis of cardiovascular diseases. We identified four independent factors (one only in women) pointing to inflammation, endothelium homeostasis, visceral fat, cardiac remodeling and lifestyles as key players in the determination of cardiovascular risk. Moreover, two of these factors improved the predictive capacity of a classical risk function.

Metabolic Processes are Potential Biological Processes Distinguishing Nonischemic Dilated Cardiomyopathy from Ischemic Cardiomyopathy: A Clue from Serum Proteomics

BACKGROUND

Ischemic cardiomyopathy (ICM) and nonischemic dilated cardiomyopathy (DCM) are the two most common causes of heart failure. However, our understanding of the specific proteins and biological processes distinguishing DCM from ICM remains insufficient.

MATERIALS AND METHODS

The proteomics analyses were performed on serum samples from ICM (n=5), DCM (n=5), and control (n=5) groups. Proteomics and bioinformatics analyses, including weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA), were performed to identify the hub circulating proteins and the hub biological processes in ICM and DCM.

RESULTS

The analysis of differentially expressed proteins and WGCNA identified the hub circulating proteins in ICM (GAPDH, CLSTN1, VH3, CP, and ST13) and DCM (one downregulated protein, FGG; 18 upregulated proteins, including HEL-S-276, IGK, ALDOB, HIST1H2BJ, HEL-S-125m, RPLP2, EL52, NCAM1, P4HB, HEL-S-99n, HIST1H4L, HIST2H3PS2, F8, ERP70, SORD, PSMA3, PSMB6, and PSMA6). The mRNA expression of the heart specimens from GDS651 validated that ALDOB, GAPDH, RPLP2, and IGK had good abilities to distinguish DCM from ICM. In addition, GSEA results showed that cell proliferation and differentiation were the hub biological processes related to ICM, while metabolic processes and cell signaling transduction were the hub biological processes associated with DCM.

CONCLUSION

The present study identified five dysregulated hub circulating proteins among ICM patients and 19 dysregulated hub circulating proteins among DCM patients. Cell proliferation and differentiation were significantly enriched in ICM. Metabolic processes were strongly enhanced in DCM and may be used to distinguish DCM from ICM.

Oxytocin mediated cardioprotection is independent of coronary endothelial function in rats

The cardioprotective effect of oxytocin (OT) has been well established. However, there are no related studies on the role of endothelia in oxytocin-induced cardioprotection. Endothelial dysfunction (ED) model was established by injection of 0.01 % Triton X-100 in the isolated rat heart. Oxytocin pretreatment was conducted at the end of stabilization for 40 min, followed by 30 min global ischemia and 60 min reperfusion to induce I/R injury. Coronary perfusion pressure, hemodynamics and arrhythmia severity scores were measured respectively. High-sensitivity cardiac troponin T (hs-cTnT) was evaluated by enzyme-linked immunosorbent assay. Infarct size was detected by triphenyltetrazolium chloride staining. The morphological changes in coronary endothelium were observed by scanning electron microscopy. Injection of 0.01 % Triton X-100 caused significant reduction of CPP induced by histamine and endothelium removal from scanning electron microscopy, but SNP had no significant effect. Oxytocin pretreatment showed significant recovery in LVDP, ±dp/dt_max, RPP and SI after reperfusion (P <  0.05). Additionally, I/R injury led to a rise of arrhythmia severity score, hs-cTnT and infarct size. No significant differences between ED-OT-I/R and OT-I/R groups were found in arrhythmia severity score, hs-cTnT, and infarct size (P >  0.05). I/R injury exacerbated the decrease in CPP and worsened the migration, deformation, and fracture of coronary endothelium, while oxytocin reversed these injuries. Despite the presence of endothelial damages, oxytocin partially alleviated I/R- and Triton-induced endothelial damages. The cardioprotective effects of oxytocin are independent of endothelial function in alleviating I/R injury and I/R-induced coronary endothelial dysfunction.