Mediator complex proximal Tail subunit MED30 is critical for Mediator core stability and cardiomyocyte transcriptional network.

Dysregulation of cardiac transcription programs has been identified in patients and families with heart failure, as well as those with morphological and functional forms of congenital heart defects. Mediator is a multi-subunit complex that plays a central role in transcription initiation by integrating regulatory signals from gene-specific transcriptional activators to RNA polymerase II (Pol II). Recently, Mediator subunit 30 (MED30), a metazoan specific Mediator subunit, has been associated with Langer-Giedion syndrome (LGS) Type II and Cornelia de Lange syndrome-4 (CDLS4), characterized by several abnormalities including congenital heart defects. A point mutation in MED30 has been identified in mouse and is associated with mitochondrial cardiomyopathy. Very recent structural analyses of Mediator revealed that MED30 localizes to the proximal Tail, anchoring Head and Tail modules, thus potentially influencing stability of the Mediator core. However, in vivo cellular and physiological roles of MED30 in maintaining Mediator core integrity remain to be tested. Here, we report that deletion of MED30 in embryonic or adult cardiomyocytes caused rapid development of cardiac defects and lethality. Importantly, cardiomyocyte specific ablation of MED30 destabilized Mediator core subunits, while the kinase module was preserved, demonstrating an essential role of MED30 in stability of the overall Mediator complex. RNAseq analyses of constitutive cardiomyocyte specific Med30 knockout (cKO) embryonic hearts and inducible cardiomyocyte specific Med30 knockout (icKO) adult cardiomyocytes further revealed critical transcription networks in cardiomyocytes controlled by Mediator. Taken together, our results demonstrated that MED30 is essential for Mediator stability and transcriptional networks in both developing and adult cardiomyocytes. Our results affirm the key role of proximal Tail modular subunits in maintaining core Mediator stability in vivo.

Circular RNA ciRs-126 promotes hypoxia/reoxygenation cardiac injury possibly through miR-21.

BACKGROUND: This study aimed to analyze the role of circular RNA ciRs-126 in hypoxia/reoxygenation cardiac injury (H/R). METHODS: Expression of ciRs-126 and miR-21 in plasma samples from patients with H/R and healthy controls was determined by RT-qPCR. Correlations were analyzed by linear regression. Overexpression of ciRs-126 and miR-21 was achieved in cardiomyocytes to explore their crosstalk. The roles of ciRs-126 and miR-21 in H/R-induced apoptosis of cardiomyocytes were analyzed using cell apoptosis assay. RESULTS: CiRs-126 was upregulated and miR-21 was downregulated in H/R patients. They were inversely correlated across plasma samples from H/R patients. In H/R cardiomyocytes, ciRs-126 was upregulated and miR-21 was downregulated. In cardiomyocytes, ciRs-126 overexpression decreased miR-21 level and reduced the inhibitory effects of miR-21 overexpression on H/R-induced cell apoptosis. CONCLUSIONS: Circular RNA ciRs-126 may suppress miR-21 expression to promote H/R cardiac injury.

Cardiac inflammation and fibrosis following chemo/radiation therapy: mechanisms and therapeutic agents.

The incidence of cardiovascular disorders is one of the most concerns among people who underwent cancer therapy. The heart side effects of cancer therapy may occur during treatment to some years after the end of treatment. Some epidemiological studies confirm that heart diseases are one of the most common reasons for mortality among patients that were received treatment for cancer. Experimental studies and also clinical investigations indicate that inflammatory changes such as pericarditis, myocarditis, and also fibrosis are key mechanisms of cardiac diseases following chemotherapy/radiotherapy. It seems that chronic oxidative stress, massive cell death, and chronic overproduction of pro-inflammatory and pro-fibrosis cytokines are the key mechanisms of cardiovascular diseases following cancer therapy. Furthermore, infiltration of inflammatory cells and upregulation of some enzymes such as NADPH Oxidases are a hallmark of heart diseases after cancer therapy. In the current review, we aim to explain how radiation or chemotherapy can induce inflammatory and fibrosis-related diseases in the heart. We will explain the cellular and molecular mechanisms of cardiac inflammation and fibrosis following chemo/radiation therapy, and then review some adjuvants to reduce the risk of inflammation and fibrosis in the heart.

Deficiency of cGAS signaling protects against sepsis-associated encephalopathy.

Sepsis is a life-threatening inflammatory syndrome secondary to infection. Thanks to the advances of antibiotics and life-supporting techniques, the mortality of sepsis has been decreasing in recent decades. Nevertheless, sepsis-associated encephalopathy (SAE) is still common in septic patients, which promotes the mortality of septic patients and results in cognitive dysfunction in survivors. Full understanding and effective medicine in the treatment of SAE is currently scant. Here, we revealed a novel role of cGAS signaling in the pathogenesis of SAE. Deficiency of cGas significantly restored cognitive impairment in sepsis mice model. The restoration may attribute to the recovery of neo-neuron decline that associated with the decrease of activated microglia and astrocytes in the hippocampus of cGas-deficient mice. In addition, type I interferon (IFN) signaling, a downstream of cGAS pathway, was boosted in the hippocampus of septic mice, which was dramatically attenuated by deleting cGas. Moreover, administration of recombinant IFNß markedly reversed the protection of ablation of cGas in the cognitive impairment in sepsis. Collectively, cGAS promotes the pathogenesis of SAE by up-regulating type I IFN signaling. Blocking cGAS may be a promising strategy for preventing encephalopathy in sepsis.

Research status and the prospect of POSTN in various tumors.

The tumor microenvironment is considered one of the main players in tumor development and progression. The tumor microenvironment composed of a large number of extracellular matrix proteins is very complex. The continuous accumulation of extracellular matrix proteins has been shown to play a key role in tumor bioregulation, including proliferation, invasion, matrix remodeling. If these processes can be detected early, and effective interventions can be given in time, the progression of the tumor may be delayed. Therefore, there is an urgent need to explore new biomarkers and therapeutic targets. In recent years, studies have shown that periostin (POSTN) may regulate multiple biological behaviors of tumor cells. Here we review the updated progress on the role of POSTN in pathologic pathways of tumor development and progression to explore whether POSTN is a potential therapeutic target.

Association Between the Left Atrial and Left Atrial Appendages Systole Strain Rate in Patients with Atrial Fibrillation.

BACKGROUND The aim of this research was to explore the association between the left atrial (LA) and left atrial appendages (LAA) systole strain rate (SSR) in patients with atrial fibrillation (AF), and to provide evidence to aid in the assessment of disease progression. MATERIAL AND METHODS A total of 180 patients with AF were selected for the study (130 patients with paroxysmal AF (Par AF) and 50 patients with persistence AF (PerAF).In addition, 60 healthy individuals were selected as a control group. The total and side wall SSRs were calculated. RESULTS The total SSR in the control group was higher than in the ParAF and PerAF groups (2.87±0.45 vs. 2.15±0.56 vs. 1.92±0.62 and 6.24±1.61 vs. 4.45±1.42 vs. 3.66±1.55). The total SSR of LAA was correlated with that of LA in the AF patient groups and the control group; the correlation coefficients were 0.720, 0.563, and 0.421. However, the ratio of total SSR of LAA to that of LA was not significant statistically different among the three groups (2.24±0.41 vs. 2.35±0.58 vs. 2.03±0.56). The posterior wall had the lowest SSRs in the control group and ParAF group. CONCLUSIONS The SSRs of AF patients were lower than that of healthy individuals, and the degree was associated with disease progression. The SSR was different in different side walls, and gradually shorten with disease progression.

The Relationship between Galectin-3 and Different Patterns of Ventricular Geometry Remodelling in Aortic Valve Stenosis.

BACKGROUND: This study was conducted to assess expression of Galectin-3 (Gal-3) in patients with different types of left ventricle (LV) hypertrophy geometry, and the relationship between Gal-3 expression and LV remodelling in patients with aortic valve stenosis (AS). METHODS: Galectin-3 expression was measured in the plasma and myocardia of AS patients who underwent an aortic valve replacement procedure. RESULTS: The study enrolled 77 consecutive patients with severe AS. Fifty-five (71.43%) of the enrolled patients had concentric hypertrophy (CH group), and had the highest degree of fibrosis (27.10±5.25%; p<0.001) and expression of Gal-3 in both plasma (19.11±2.06 ng/mL) and myocardial tissue (3.01±0.79). There was a strong positive correlation between the levels of fibrosis and Gal-3 expression in both plasma (r=0.584, p<0.001) and myocardium (r=0.522, p<0.001). Relative wall thickness (RWT) was strongly correlated with Gal-3 expression in both myocardium (r=0.594, p<0.001) and plasma (r=0.323, p=0.005). Additionally, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were positively correlated with both fibrosis (r=0.313, p=0.036) and LV mass index (r=0.559, p<0.001). CONCLUSIONS: Concentric hypertrophy geometry was the most common type of myocardium remodelling, and AS patients with CH geometry showed the highest levels of Gal-3 expression. Galectin-3 levels were positively correlated with fibrosis and RWT, both of which are crucial indicators of geometric remodelling. Galectin-3 and NT-proBNP levels may be valuable prognostic predictors in AS patients with myocardial remodelling.

Apelin attenuates the osteoblastic differentiation of aortic valve interstitial cells via the ERK and PI3-K/Akt pathways.

Aortic valve calcification (AVC), which used to be recognized as a passive and irreversible process, is now widely accepted as an active and regulated process characterized by osteoblastic differentiation of aortic valve interstitial cells (AVICs). Apelin, the endogenous ligand for G-protein-coupled receptor APJ, was found to have protective cardiovascular effects in several studies. However, the effects and mechanisms of apelin on osteoblastic differentiation of AVICs have not been elucidated. Using a pro-calcific medium, we devised a method to produce calcific human AVICs. These cells were used to study the relationship between apelin and the osteoblastic calcification of AVICs and the involved signaling pathways. Alkaline phosphatase (ALP) activity/expression and runt-related transcription factor 2 (Runx2) expression were examined as hallmark proteins in this research. The involved signaling pathways were studied using the extracellular signal-regulated kinase (ERK) inhibitor, PD98059, and the phosphatidylinositol 3-kinase (PI3-K) inhibitor, LY294002. The results indicate that apelin attenuates the expression and activity of ALP, the expression of Runx2, and the formation of mineralized nodules. This protective effect was dependent on the dose of apelin, reaching the maximum at 100 pM, and was connected to activity of ERK and Akt (a downstream effector of PI3-K). The activation of ERK and PI3-K initiated the effects of apelin on ALP activity/expression and Runx2, but PD98059 and LY294002 abolished the effect. These results demonstrate that apelin attenuates the osteoblastic differentiation of AVICs via the ERK and PI3-K/Akt pathway.

Liraglutide Attenuates Aortic Valve Calcification in a High-Cholesterol-Diet-Induced Experimental Calcific Aortic Valve Disease Model in Apolipoprotein E-Deficient Mice.

BACKGROUND: Calcific aortic valve disease (CAVD) is a significant cause of morbidity and mortality among elderly people. However, no effective medications have been approved to slow or prevent the progression of CAVD. Here, we examined the effect of liraglutide on aortic valve stenosis. METHODS: Male Apoe-/- mice were fed with a high-cholesterol diet for 24 weeks to generate an experimental CAVD model and randomly assigned to a liraglutide treatment group or control group. Echocardiography and immunohistological analyses were performed to examine the aortic valve function and morphology, fibrosis, and calcium deposition. Plasma Glucagon-like peptide-1 (GLP-1) levels and inflammatory contents were measured via ELISA, FACS, and immunofluorescence. RNA sequencing (RNA-seq) was used to identify liraglutide-affected pathways and processes. RESULTS: Plasma GLP-1 levels were reduced in the CAVD model, and liraglutide treatment significantly improved aortic valve calcification and functions and attenuated inflammation. RNA-seq showed that liraglutide affects multiple myofibroblastic and osteogenic differentiations or inflammation-associated biological states or processes in the aortic valve. Those liraglutide-mediated beneficial effects were associated with increased GLP-1 receptor (GLP-1R) expression. CONCLUSIONS: Liraglutide blocks aortic valve calcification and may serve as a potential therapeutic drug for CAVD treatment.

H19 Promotes Osteoblastic Transition by Acting as ceRNA of miR-140-5p in Vascular Smooth Muscle Cells.

Arterial medial calcification is a common disease in patients with type 2 diabetes, end-stage renal disease and hypertension, resulting in high incidence and mortality of cardiovascular event. H19 has been demonstrated to be involved in cardiovascular diseases like aortic valve diseases. However, role of H19 in arterial medial calcification remains largely unknown. We identified that H19 was upregulated in ß-glycerophosphate (ß-GP) induced vascular smooth muscle cells (VSMCs), a cellular calcification model in vitro. Overexpression of H19 potentiated while knockdown of H19 inhibited osteogenic differentiation of VSMCs, as demonstrated by changes of osteogenic genes Runx2 and ALP as well as ALP activity. Notably, H19 interacted with miR-140-5p directly, as demonstrated by luciferase report system and RIP analysis. Mechanistically, miR-140-5p attenuated osteoblastic differentiation of VSMCs by targeting Satb2 and overexpression of miR-140-5p blocked H19 induced elevation of Satb2 as well as the promotion of osteoblastic differentiation of VSMCs. Interestingly, over-expression of Satb2 induced phosphorylation of ERK1/2 and p38MAPK. In conclusion, H19 promotes VSMC calcification by acting as competing endogenous RNA of miR-140-5p and at least partially by activating Satb2-induced ERK1/2 and p38MAPK signaling.

Cardiolipin Remodeling Defects Impair Mitochondrial Architecture and Function in a Murine Model of Barth Syndrome Cardiomyopathy.

BACKGROUND: Cardiomyopathy is a major clinical feature in Barth syndrome (BTHS), an X-linked mitochondrial lipid disorder caused by mutations in Tafazzin (TAZ), encoding a mitochondrial acyltransferase required for cardiolipin remodeling. Despite recent description of a mouse model of BTHS cardiomyopathy, an in-depth analysis of specific lipid abnormalities and mitochondrial form and function in an in vivo BTHS cardiomyopathy model is lacking. METHODS: We performed in-depth assessment of cardiac function, cardiolipin species profiles, and mitochondrial structure and function in our newly generated Taz cardiomyocyte-specific knockout mice and Cre-negative control mice (n≥3 per group). RESULTS: Taz cardiomyocyte-specific knockout mice recapitulate typical features of BTHS and mitochondrial cardiomyopathy. Fewer than 5% of cardiomyocyte-specific knockout mice exhibited lethality before 2 months of age, with significantly enlarged hearts. More than 80% of cardiomyocyte-specific knockout displayed ventricular dilation at 16 weeks of age and survived until 50 weeks of age. Full parameter analysis of cardiac cardiolipin profiles demonstrated lower total cardiolipin concentration, abnormal cardiolipin fatty acyl composition, and elevated monolysocardiolipin to cardiolipin ratios in Taz cardiomyocyte-specific knockout, relative to controls. Mitochondrial contact site and cristae organizing system and F1F0-ATP synthase complexes, required for cristae morphogenesis, were abnormal, resulting in onion-shaped mitochondria. Organization of high molecular weight respiratory chain supercomplexes was also impaired. In keeping with observed mitochondrial abnormalities, seahorse experiments demonstrated impaired mitochondrial respiration capacity. CONCLUSIONS: Our mouse model mirrors multiple physiological and biochemical aspects of BTHS cardiomyopathy. Our results give important insights into the underlying cause of BTHS cardiomyopathy and provide a framework for testing therapeutic approaches to BTHS cardiomyopathy, or other mitochondrial-related cardiomyopathies.

Adipose tissue-derived omentin-1 attenuates arterial calcification via AMPK/Akt signaling pathway.

Adipose tissue-derived adipokines mediate various kind of crosstalk between adipose tissue and other organs and thus regulate metabolism balance, inflammation state as well as disease progression. In particular, omentin-1, a newly found adipokine, has been reported to exhibit anti-calcification effects in vitro and in vivo. However, little is known about the function of endogenous adipose tissue-derived omentin-1 in arterial calcification and the detailed mechanism involved. Here, we demonstrated that global omentin-1 knockout (omentin-1-/-) resulted in more obvious arterial calcification in 5/6-nephrectomy plus high phosphate diet treated (5/6 NTP) mice while overexpression of omentin-1 attenuated attenuates osteoblastic differentiation and mineralisation of VSMCs in vitro and 5/6 NTP-induced mice arterial calcification in vivo. Moreover, we found that omentin-1 induced AMPK and Akt activation while inhibition of AMP-activated protein kinase (AMPK) and Akt signaling reversed the anti-calcification effect induced by omentin-1 both in vitro and in vivo. Our results suggest that adipose tissue-derived omentin-1 serves as a potential therapeutic target for arterial calcification and cardiovascular disease.

Isolated cardiac peripheral primitive neuroectodermal tumor: A case report.

BACKGROUND: Peripheral primitive neuroectodermal tumor isolated in the heart, presenting as a primary cardiac tumor is considered as extremely rare. METHODS: We present a 53-year-old Chinese female with a cardiac tumor which was discovered by CT. RESULTS: A hypo-intense tumorous mass was shown extending from the left ventricle by Cardiac CT, and fused FDG positron emission tomography demonstrated no other abnormal FDG active lesions in the body. We performed a total resection surgery of the tumor subsequently and the patient recovered well and discharged from hospital 6 d after surgery. CONCLUSION: The pathological diagnosis was primary cardiac peripheral primitive neuroectodermal tumor. No tumor recurrence was shown by echocardiography during the 24 months follow-up visits.

A Giant Cavernous Hemangioma of the Left Atrioventricular Groove.

A 10-year-old Chinese female diagnosed with an asymptomatic giant cardiac cavernous hemangioma was reported. The patient originally tended to observation because this unusual cardiac tumoral mass was discovered incidentally during routine health examination of transthoracic echocardiography. Over 5 years of follow-up, the mass had enlarged obviously, and the patient visited our outpatient clinic and was prone to excision. Subsequently, a total resection surgery of the tumor was performed, and the tumor was found to be located on the left atrioventricular groove with complete packing membrane. The patient was discharged on postoperative day 4 and remains asymptomatic on last follow-up.

Effects of remote ischemic preconditioning on the flow pattern of the left anterior descending coronary artery in normal subjects.

Remote ischemic preconditioning (RIPC) has been proposed as an effective method to improve both myocardial and vascular protection in human beings. The aim of this study was to identify the effect of RIPC on the flow pattern of left anterior descending coronary artery (LAD) by transthoracic Doppler echocardiography. 18 normal male volunteers were enrolled to this study. The Doppler signals of flow velocity were recorded at baseline, 1, 3, 6 and 9 min after reperfusion of each cycle to identify the effect of RIPC on the flow pattern of the LAD. In the study, the coronary mean velocity, peak diastolic velocity and mean diastolic velocity were increased (all P<0.05) in the first 3 min of reperfusion of each cycle while peak systolic velocity, mean systolic velocity and heart rate did not change compared with the baseline readings throughout RIPC. And the maximal coronary flow velocity was observed at the first minute of the second reperfusion. The result of this study proves that remote ischemic preconditioning produces hyperemia via the LAD during early reperfusion, which is characterized by an increase in diastolic flow velocity.