DKK3 overexpression attenuates cardiac hypertrophy and fibrosis in an angiotensin-perfused animal model by regulating the ADAM17/ACE2 and GSK-3ß/ß-catenin pathways.

AIMS: Cardiac pressure and humoral factors induce cardiac hypertrophy and fibrosis, which are characterized by increased stiffness, reduced contractility and altered perfusion. Angiotensin II (AngII) is well known to promote this pathology. Angiotensin-converting enzyme (ACE) 2, which cleaves AngII and forms Ang-(1-7), exerts protective anti-hypertrophy and anti-fibrosis effects. A disintegrin and metalloproteinase 17 (ADAM17), a membrane-bound enzyme reported to cleave ACE2, may participate in the pathological process of AngII perfusion-induced heart damage. However, researchers have not clearly determined whether dickkopf-3 (DKK3) regulates the ADAM17/ACE2 pathway and, if so, whether DKK3-mediated regulation is related to the glycogen synthase kinase-3ß (GSK-3ß)/ß-catenin pathway. In this study, we explored whether DKK3 overexpression ameliorates the development of AngII-induced cardiac fibrosis and hypertrophy through the ADAM17/ACE2 and GSK-3ß/ß-catenin pathways. METHODS: Mice were injected with a DKK3-overexpressing adenovirus or vehicle and then infused with AngII or saline using subcutaneously implanted mini-pumps for four weeks. Hearts were stained with hematoxylin-eosin, Masson's trichrome and immunohistochemical markers for histology. Primary fibroblasts were treated with the adenovirus and AngII and then examined using western blotting, EdU (5-ethynyl-2'-deoxyuridine) assays and immunofluorescence. Additionally, siRNA silencing was performed to study the role of DKK3 and the involved pathways. RESULTS: AngII-induced cardiac hypertrophy and interstitial and perivascular fibrosis were less severe in DKK3-overexpressing mice than in control mice. Moreover, the expression levels of fibrotic genes, such as collagen I and III, and the hypertrophic genes atrial natriuretic peptide (ANP) and beta-myosin heavy chain (ß-MHC) were decreased. DKK3 overexpression also exerted a protective effect by inhibiting ADAM17 phosphorylation, thus increasing ACE2 expression and subsequently promoting AngII degradation. Furthermore, this process was mediated by the inhibition of GSK-3ß and ß-catenin and decreased translocation of ß-catenin to the nucleus. On the other hand, the DKK3 knockdown by siRNA achieved opposite results. CONCLUSION: DKK3 overexpression substantially alleviated AngII infusion-induced cardiac hypertrophy and fibrosis by regulating ADAM17/ACE2 pathway activity and inhibiting the GSK-3ß/ß-catenin pathway.

Irisin inhibits high glucose-induced endothelial-to-mesenchymal transition and exerts a dose-dependent bidirectional effect on diabetic cardiomyopathy.

Emerging evidence indicates that irisin provides beneficial effects in diabetes. However, whether irisin influences the development of diabetic cardiomyopathy (DCM) remains unclear. Therefore, we investigated the potential role and mechanism of action of irisin in diabetes-induced myocardial dysfunction in mice. Type 1 diabetes was induced in mice by injecting streptozotocin, and the diabetic mice were administered recombinant r-irisin (low or high dose: 0.5 or 1.5 µg/g body weight/day, I.P.) or PBS for 16 weeks. Irisin treatment did not alter blood glucose levels in the diabetic mice. However, the results of echocardiographical and histopathological assays indicated that low-dose irisin treatment alleviated cardiac fibrosis and left ventricular function in the diabetic mice, whereas high-dose irisin failed to mitigate the ventricular function impairment and increased collagen deposition. The potential mechanism underlying the effect of low-dose irisin involved irisin-mediated inhibition of high glucose-induced endothelial-to-mesenchymal transition (EndMT); conversely, high-dose irisin treatment enhanced high glucose-induced MMP expression by stimulating MAPK (p38 and ERK) signalling and cardiac fibroblast proliferation and migration. Low-dose irisin alleviated DCM development by inhibiting high glucose-induced EndMT. By contrast, high-dose irisin disrupted normal MMP expression and induced cardiac fibroblast proliferation and migration, which results in excess collagen deposition. Thus, irisin can inhibit high glucose-induced EndMT and exert a dose-dependent bidirectional effect on DCM.

Berberine Attenuates Vascular Remodeling and Inflammation in a Rat Model of Metabolic Syndrome.

Berberine is a natural product that shows benefits for metabolic syndrome (MS). However, the effects of berberine on the improvement of vascular inflammation and remodeling in MS remain unclear. This study aimed to investigate whether berberine could prevent vascular remodeling and inflammation in the MS condition. A rat model of MS was established, and MS rats were divided into two groups: MS group without berberine treatment, and MSB group with berberine treatment (each group n-10). Ten normal Wistar rats were used as controls (NC group). Vascular damage was examined by transmission electron microscopy and pathological staining. Compared to the NC group, the secretion of inflammatory factors was increased and the aortic wall thicker in the MS group. The MSB group exhibited decreased secretion of inflammatory factors and improved vascular remodeling, compared to the MS group. In addition, the levels of p38 mitogen-activated protein kinase (p38 MAPK), activating transcription factor 2 (ATF-2) and matrix metalloproteinase 2 (MMP-2) were significantly decreased in the MSB group compared to the MS group. In conclusion, our data show that berberine improves vascular inflammation and remodeling in the MS condition, and this is correlated with the ability of berberine to inhibit p38 MAPK activation, ATF-2 phosphorylation, and MMP-2 expression.

[Bone marrow mesenchymal stem cells to repair the reproductive system of male azoospermia rats].

OBJECTIVE: To study the ability of bone marrow mesenchymal stem cells (BMSCs) to repair the internal environment of the testis in male azoospermia rats. METHODS: We established azoospermia models in 22 six-week-old male SD rats by intraperitoneal injection of busulfan at 20 mg per kg body weight. We transplanted allogeneic rat BMSCs (rBMSCs) into the testicular seminiferous tubules of the model rats and, 30 days after transplantation, observed the composition and structure of the seminiferous tubular cells by HE staining and detected the expressions of CD44, CD106, and c-kit in the rBMSCs by immunohistochemistry. RESULTS: The number of epididymal sperm was significantly reduced in the model rats as compared with the normal controls (P < 0.01). CD44 and CD106, but not c-kit, were expressed in the isolated rBMSCs. At 30 days after transplantation of rBMSCs, lots of new cells were observed in the seminiferous tubules, some expressing CD106 and some expressing the germ cell surface marker c-kit. CONCLUSION: BMSCs can transdifferentiate into germ cells and repair the damaged seminiferous tubules of sterile rats.

The transcriptional co-activator multiprotein bridging factor 1 from the fungal insect pathogen, Beauveria bassiana, mediates regulation of hyphal morphogenesis, stress tolerance and virulence.

Multiprotein bridging factors (MBFs) are evolutionarily highly conserved cofactors that link TATA-binding protein and the associated basal transcription machinery to transcription factors. The filamentous fungus, Beauveria bassiana, has a multipotential lifestyle capable of growing as a saprophyte, plant endophyte and insect pathogen. Deletion of the single B. bassiana MBF homologue (BbMBF1) affected fungal growth and hyphal morphogenesis, stress response and virulence. Compared with wild type, the ΔBbMBF1 strain displayed increased sensitivity to UV-irradiation and to oxidative, osmotic and heat stress, and decreased virulence in both topical and intrahaemocoel injection bioassays using the greater wax moth, Galleria mellonella larvae. Although only minor radial growth effects were seen for the ΔBbMBF1 strain, aberrant hyphal morphogenesis was observed, which could be rescued by growth in rich broth media. Transcriptional analysis during stress response showed altered gene expression in ΔBbMBF1 during growth under osmotic, oxidative and thermal stress conditions. Genome-wide expression analyses during growth under unstressed and thermal stress conditions revealed global gene expression changes and a set of putative targets for MBF1 mediated gene expression control. Our data indicate that BbMBF1 acts as a key regulatory cofactor controlling stress responses and virulence and that MBF1 dependent and independent pathways control proper hyphal morphogenesis.

STING deficiency alleviates ferroptosis through FPN1 stabilization in diabetic kidney disease.

Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, has known as one of the most significant pathological processes involved in diabetic kidney disease (DKD). Stimulator of interferon genes (STING) has been demonstrated its potential in regulating ferroptosis, but the regulatory role in DKD mice and underlying mechanisms haven't been illustrated. To elucidate whether and how STING regulates ferroptosis in DKD, we detected the influence of STING on diabetic-related ferroptosis in a diabetic model and in erastin-induced renal tubular epithelial cells (RTECs). Our study demonstrated that STING was abnormally activated and promoted ferroptosis in DKD. STING deficiency alleviated renal pathologic damages and disfunction in diabetic mice via alleviating ferroptosis and reducing oxidative stress. Mechanismly, STING inhibition was shown to improve ferroptosis and reduce oxidative stress in erastin-induced RTECs. The disruption of ferroportin1 (FPN1) on the basis of STING inhibition abolished the improvements in ferroptosis and promoted reactive oxygen species (ROS) generation. Further, STING inhibition alleviated ferroptosis via stabilizing FPN1 protein level by decreasing ubiquitinated FPN1 for proteasomal degradation. In conclusion, STING deficiency protected against diabetic renal injury via alleviating ferroptosis through stabilizing FPN1 and reducing oxidative stress, providing a possible potential approach for the treatment of DKD.

Stimulator of interferon genes promotes diabetic sarcopenia by targeting peroxisome proliferator activated receptors γ degradation and inhibiting fatty acid oxidation.

BACKGROUND: Declined skeletal muscle mass and function are inevitable consequences of long-term diabetes and bring about many adverse events. Muscle fibre atrophy and interstitial fibrosis are major pathological manifestations of diabetic sarcopenia. Stimulator of interferon genes (STING) participates in various metabolic diseases. We aimed to explore whether and how STING regulates the above pathological manifestations of diabetic sarcopenia. METHODS: Wild-type and STINGgt/gt C57BL/6J mice and C2C12 myotubes were used to study the role of STING in the regulation of diabetic sarcopenia and the underlying mechanisms. RESULTS: STING was abnormally activated in diabetic muscles and in PA-treated myotubes (P < 0.01 for all parameters). The diabetic mice demonstrated decreased forelimb grip strength, lean mass, muscle weight and hanging impulse, which were improved by STING deficiency due to alleviated muscle fibre atrophy and interstitial fibrosis (P < 0.05 for all parameters). STING deficiency alleviated muscle fibre atrophy through the following mechanisms. Firstly, STING deficiency or inhibition increased the contents of pDRP1Ser616 , PINK1, Parkin and LC3-II, decreased p62 content, and increased the amount of mito-Keima fluorescent dots at 578 nm in diabetic state (P < 0.05 for all parameters), suggesting improved mitofission and mitophagy. Secondly, STING deficiency or inhibition increased the expression of pAKTSer473 and GLUT4 post-insulin change in diabetic state (P < 0.05 for all), indicating alleviated insulin resistance (IR). Mechanically, STING deficiency or inhibition increased peroxisome proliferator activated receptors γ (PPARγ) protein content by reducing the degradation of ubiquitinated PPARγ through the proteasome pathway and thus increased the expression of fatty acid oxidation (FAO)-related proteins in diabetic state (P < 0.05 for all parameters). Decreased expression of FAO-related proteins caused by PPARγ inhibition abolished the improvements in mitofission, mitophagy and IR achieved by STING inhibition in PA-treated myotubes and thus promoted muscle fibre atrophy (P < 0.05 for all parameters). STING deficiency alleviated interstitial fibrosis by decreasing TGFß1 expression in diabetic state and TGFß1 promoted the fibrogenic differentiation of fibro-adipogenic progenitors (P < 0.05 for all parameters). PPARγ inhibition abolished the effect of STING inhibition on reducing TGFß1 content in PA-treated myotubes (P < 0.01). CONCLUSIONS: STING deficiency exerted protective effects in diabetic sarcopenia by inhibiting the degradation of ubiquitinated PPARγ through the proteasome pathway and enhancing PPARγ-mediated FAO, which alleviated muscle fibre atrophy by promoting mitophagy and ameliorating IR, and alleviated interstitial fibrosis by reducing TGFß1 production and suppressing the fibrogenic differentiation of fibro-adipogenic progenitors.

Lomatogonium rotatum extract alleviates diabetes mellitus induced by a high-fat, high-sugar diet and streptozotocin in rats.

BACKGROUND: Lomatogonium rotatum (LR) is traditionally used in Mongolian folk medicine as a hypoglycemic agent, but its evidence-based pharmacological effects and me-chanisms of action have not been fully elucidated. AIM: To emphasize the hypoglycemic action mechanism of LR in a type 2 diabetic rat model and examine potential biomarkers to obtain mechanistic understanding regarding serum metabolite modifications. METHODS: A high-fat, high-sugar diet and streptozotocin injection-induced type 2 diabetic rat model was established. The chemical composition of the LR was identified by high performance liquid chromatography. LR extract administrated as oral gavage at 0.5 g/kg, 2.5 g/kg, and 5 g/kg for 4 wk. Anti-diabetic effects of LR extract were evaluated based on histopathological examination as well as the measurement of blood glucose, insulin, glucagon-like peptide 1 (GLP-1), and lipid levels. Serum metabolites were analyzed using an untargeted metabolomics approach. RESULTS: According to a chemical analysis, swertiamarin, sweroside, hesperetin, coumarin, 1.7-dihydroxy-3,8-dimethoxyl xanthone, and 1-hydroxy-2,3,5 trimethoxanone are the principal active ingredients in LR. An anti-diabetic experiment revealed that the LR treatment significantly increased plasma insulin and GLP-1 levels while effectively lowering blood glucose, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and oral glucose tolerance test compared to the model group. Furthermore, untargeted metabolomic analysis of serum samples detected 236 metabolites, among which 86 were differentially expressed between the model and the LR group. It was also found that LR considerably altered the levels of metabolites such as vitamin B6, mevalonate-5P, D-proline, L-lysine, and taurine, which are involved in the regulation of the vitamin B6 metabolic pathway, selenium amino acid metabolic pathway, pyrimidine metabolic pathway, and arginine and proline metabolic pathways. CONCLUSION: These findings indicated that LR may have a hypoglycemic impact and that its role may be related to changes in the serum metabolites and to facilitate the release of insulin and GLP-1, which lower blood glucose and lipid profiles.

Efficacy and safety of sacubitril/valsartan after six months in patients with heart failure with reduced ejection fraction and asymptomatic hypotension.

BACKGROUND: It is not clear whether sacubitril/valsartan is beneficial for patients with heart failure (HF) with reduced ejection fraction (HFrEF) and low systolic blood pressure (SBP). This study aimed to investigate the efficacy and tolerability of sacubitril/valsartan in HFrEF patients with SBP < 100 mmHg. METHODS & RESULTS: An observational study was conducted on 117 patients, 40.2% of whom had SBP < 100 mmHg without symptomatic hypotension, and 59.8% of whom had SBP ≥ 100 mmHg in an optimized HF follow-up management system. At the 6-month follow-up, 52.4% of patients with SBP < 100 mmHg and 70.0% of those with SBP ≥ 100 mmHg successfully reached the target dosages of sacubitril/valsartan. A reduction in the concentration of N-terminal pro-B-type natriuretic peptide was similar between patients with SBP < 100 mmHg and SBP ≥ 100 mmHg (1627.5 pg/mL and 1340.1 pg/mL, respectively; P = 0.75). The effect of sacubitril/valsartan on left ventricular ejection fraction was observed in both SBP categories, with a 10.8% increase in patients with SBP < 100 mmHg (P < 0.001) and a 14.0% increase in patients with SBP ≥ 100 mmHg (P < 0.001). The effects of sacubitril/valsartan on SBP were statistically significant and inverse across both SBP categories (P = 0.001), with an increase of 7.5 mmHg in patients with SBP < 100 mmHg and a decrease of 11.5 mmHg in patients with SBP ≥ 100 mmHg. No statistically significant differences were observed between the two groups in terms of the occurrence of symptomatic hypotension, deteriorating renal function, hyperkalemia, angioedema, or stroke. CONCLUSIONS: Within an optimized HF follow-up management system, sacubitril/valsartan exhibited excellent tolerability and prompted left ventricular reverse remodeling in patients with HFrEF who presented asymptomatic hypotension.

Simvastatin exerts cardioprotective effects and inhibits the activity of Rho-associated protein kinase in rats with metabolic syndrome.

1. Insulin resistance (IR) is crucially involved in the pathophysiology of metabolic syndrome (MS). The aim of the present study was to investigate the effects of simvastatin on IR in rats with MS. 2. A rat model of MS was established and myocardial damage was examined by transmission electron microscopy. Twenty-two MS rats were divided into two groups of 11 rats each: (i) an MS group; and (ii) a simvastatin-treated MS. Ten Wistar rats were used as controls. The phosphorylation of myosin phosphatase target subunit 1 (MYPT-1), insulin receptor substrate 1 (IRS-1) and Akt were analysed by immunohistochemistry and western blotting. 3. Insulin resistance-induced MS was associated with a significant increase in Rho kinase (ROCK) activity and inhibition of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. Decreased levels of phosphorylated (p-) MYPT-1 and p-IRS-1 (Ser³°7) and increased levels of p-Akt were found in hearts from the MS + simvastatin compared with the MS group. These results suggest that simvastatin reduces ROCK activity and increases Akt activity. 4. Simvastatin exerts cardioprotective effects and improves IR, which can be attributed, at least in part, to the inhibition of ROCK and activation of PI3-K/Akt.

[Poly (ADP-ribose) polymerase inhibition attenuates ischemia/reperfusion induced myocardial injury in rat via reducing myocardial nuclear factor κB activity].

OBJECTIVE: To investigate the effect of Poly (ADP-ribose) polymerase (PARP) inhibition on ischemia/reperfusion (I/R) induced myocardial injury in rat and related mechanisms. METHOD: Adult Wistar rats were randomly divided into sham-control (n = 18), I/R (60 min ischemia followed by 180 min reperfusion, n = 18) and I/R + PARP inhibitor 3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-1(2H)-isoquinolinone (DPQ), 10 mg/kg, i.p. injection at 1 h before I/R (n = 18). Myocardial expression of PARP, infarct size, and cardiomyocytes apoptosis were determined. Additionally, myocardial NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 at protein and mRNA level were detected. RESULT: (1) Myocardial expression of PARP was significantly upregulated in I/R group compared to sham-control group, which could be significantly reduced by pretreatment with DPQ (P < 0.05 vs. I/R group). (2) Infarct size [(31.45 ± 5.54)% vs. (45.97 ± 4.22)%] and cardiomyocytes apoptosis [(23.0 ± 3.8)% vs. (34.0 ± 6.2)%] were significantly reduced by pretreatment with DPQ (all P < 0.05 vs. I/R group). (3) Pretreatment with DPQ also significantly decreased the NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 at both protein and mRNA level (all P < 0.05). CONCLUSION: The expression of PARP, NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 are upregulated in I/R induced myocardial injury. PARP inhibitor DPQ could attenuate I/R induced myocardial injury through reducing NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9.

[Predictors of vulnerable atherosclerotic plaques induced by cholesterol and balloon injury in rabbits].

OBJECTIVE: To detect the optimal predictors of vulnerable atherosclerotic plaques. METHODS: Forty New Zealand white rabbits underwent balloon-induced abdominal aortic wall injury and were fed a high cholesterol and saturated fat diet containing 1% cholesterol for 8 weeks. Rabbits were then randomly divided into two groups: group A (n = 20, the aortic segments rich in plaques were incubated transluminally with recombinant adenovirus carrying p53) and group B [n = 20, incubated transluminally with ß galactosidase (LacZ) genes]. Two weeks later, rabbits underwent pharmacological triggering with injection of Chinese Russell's viper venom (CRVV) and histamine. Before pharmacologically triggering, concentrations of hs-CRP, sVCAM-1 and sICAM-1 were measured by means of Enzyme-linked-immunosorbent assay (ELISA). Fibrinogen was analyzed by nephelometer. Ultrasound imaging, accuracy densitometry (AD) examination and intravascular ultrasound (IVUS) were performed to analyze the in vivo features of vulnerable plaques. Logistic regression was used to detect the predictors for vulnerable plaques. RESULTS: The ratio of plaque rupture after pharmacological triggering was significantly higher in group A (89.5%, 17/19) than in group B (22.2%, 4/18). Serum hs-CRP level was significantly higher in plaque rupture group than in non-rupture group before pharmacological triggering (P < 0.05). In the meantime, parameters derived from ultrasound imaging [intima-media thickness (IMT) and peak velocity (VP), values of accuracy densitometry], measurements of IVUS [external elastic membrance area (EEMA), plaque area (PA), plaque burden (PB), eccentric index (EI) and remodeling index (RI)] were significantly larger in plaque rupture group than in non-rupture group. Logistic regression showed that EI (OR = 26.917), PA (OR = 19.301), sVCAM-1 (OR = 1.339) and AII-c% (OR = 0.458) were independent predictors for plaque rupture (all P < 0.05). CONCLUSION: The major predictors of vulnerable plaques were eccentric index (EI) and plaque area (PA), sVCAM-1 and AII-c% in this model.

Evaluation of fetal cardiac functions in the setting of maternal diabetes: Application of the global spherical index, global strain and fractional area change by the speckle tracking technique.

OBJECTIVE: To evaluate ventricular contractility and profile heart deformations in fetuses of hyperglycemic mothers using the Speckle tracking imaging (STI). The fractional area change (FAC), global longitudinal strain (GLS) and global sphericity index (GSI) of the 4-chamber view (4-CV) were computed. STUDY DESIGN: Dynamic 4-CV images of 60 fetuses exposed to maternal diabetes (MD) and 60 controls were retrospectively collected between 19 and 37 weeks of gestation. Speckle-tracking analysis was used to compute and compare GSI, GLS and FAC of the right ventricle (RV) and the left ventricle (LV) between the groups. By definition, GSI was the ratio of the epicardial basal-apical length in end-diastole (BAL) to the overall transverse length of RV and LV in end-diastole (TL). The FAC was calculated by dividing the difference between end-diastolic area and end-systolic area by the end-diastolic area. Similarly, the GLS of the RV and LV was obtained by dividing the difference between the endocardial length in end-systole and endocardial length in end-diastole to the endocardial length in end-diastole. Data for conventional echocardiographic parameters, standard biological measurements of fetus and maternal baseline characteristics were also recorded and compared between the groups. Linear regression analysis was performed to assess the association between age, BMI and the inter-ventricular septum thickness (IVST). RESULTS: Gestational age at the time of examination did not differ significantly between the control and gestational diabetes group (p = 0.74). In fetuses exposed to MD, the thickness of the IVS was higher while the FAC of RV, GLS of RV and the GSI were all significantly lower. The FAC and global strain of LV generally decreased with progress in gestation but the difference between the two groups was not statistically significant. Conventional echocardiography in fetuses exposed to MD revealed a lower mitral E/A ratio and a larger myocardial performance index (MPI) of the RV and LV. Although the annular plane systolic excursion (MAPSE), tricuspid annular plane systolic excursion (TAPSE) and septal annular plane systolic excursion (SAPSE) were also lower in this group, the difference was not statistically significant compared to fetuses of the control group. No regression relationship between age, BMI and IVST were noticed in any group. CONCLUSION: This study found that diastolic dysfunction among fetuses of gestational diabetic mothers is accompanied by global cardiac deformation and functional decrease of the RV in systole in the second and third trimester. The GSI, global strain and FAC acquired by SRI can be used as convenient and reliable quantitative parameters in the assessment of cardiac function in fetuses exposed to gestational diabetes.

ERK-MAPK signaling opposes rho-kinase to reduce cardiomyocyte apoptosis in heart ischemic preconditioning.

We and others have reported that Rho-kinase plays an important role in the pathogenesis of heart ischemia/reperfusion (I/R) injury. Studies have also demonstrated that the activation of Rho-kinase is reversed in ischemic preconditioning (IPC). However, the mechanisms by which Rho-kinase is increased in I/R and reversed in IPC are not thoroughly understood. In female Wistar rats, we created I/R by ligating the left anterior-descending branch of the coronary artery (LAD) for 30 min and releasing the ligature for 180 min. IPC rats underwent IPC (two cycles of 5-min ligation of the LAD and 5-min reflow) before I/R. IPC caused a significant increase in extracellular signal-regulated kinase (ERK)1/2 activity and reduced Rho-kinase activity and cardiomyocyte apoptosis (P<0.05 versus I/R). Administration of PD98059, an inhibitor of ERK-mitogen-activated protein kinase (MAPK), increased cardiomyocyte apoptosis, Caspase-3 activity and myocardial infarction size (P<0.05 versus IPC). Western-blot analysis showed that administration of PD98059 increased Rho-kinase activity. Treatment with fasudil, an inhibitor of Rho-kinase, reversed cell apoptosis caused by treatment with PD98059 in IPC. In addition, ROCK1 (Rho-kinase 1) may be the major Rho-kinase isoform that is opposed by ERK-MAPK signaling in IPC. These results indicate that ERK-MAPK signaling is required in IPC to oppose Rho-kinase activity in cardiomyocyte apoptosis in vivo.

Effect of Elevated Pulmonary Artery Systolic Pressure on Short-Term Prognosis in Patients With Acute Myocardial Infarction.

Pulmonary artery systolic pressure (PASP) may increase because of cardiac alterations that result in increased filling pressures after acute myocardial infarction (AMI). We hypothesized that PASP might be a useful maker to predict the risk of cardiac death after AMI. We carried out a retrospective study from 2013 to 2017 involving 5401 patients with AMI. Patients were grouped according to their admission PASP result, and the primary end point was cardiac death in 6 months after AMI. Pulmonary artery systolic pressure was associated with age, AMI site, Killip classification, and decreased ejection fraction. After adjustments for clinical and echocardiographic parameters in a Cox model, PASP was found to be significantly related to cardiac death. In receiver operating characteristic analysis, PASP >30 mm Hg had a sensitivity of 59.8% and a specificity of 62.5% for predicting 6-month cardiac death after AMI. In conclusion, PASP at the index admission may be a useful marker predicting short-term cardiac death. These results have implications for future research and management of patients with AMI.

Intraplaque injection of Ad5-CMV.p53 aggravates local inflammation and leads to plaque instability in rabbits.

This study aims to develop a new animal model of vulnerable plaques and investigate the potential mechanisms of exogenous p53-induced plaque instability. Forty rabbits underwent aortic balloon injury, were fed a 1% cholesterol diet for 10 weeks and then normal chow for 6 weeks. Rabbits were divided into Ad5-CMV.p53-treated group (n = 16), Ad5-CMV.lac Z-treated group (n = 16) and blank control group (n = 8). Under the guidance of intravascular ultrasound, a 50-microl suspension of adenovirus containing p53 or lac Z was injected into the largest plaque of the first two groups, respectively, and these rabbits received pharmacological triggering 2 weeks later. In 76.9% of rabbits with p53 transfection, plaque rupture was found, which was significantly (P < 0.05) higher than that in the Ad5-CMV.lac Z-treated plaques (23.1%), or blank controls plaques (0%). Increased apoptotic cells, and subsequently, decreased vascular smooth muscle cells and collagen content, enhanced intima macrophage accumulation, increased C-reactive protein (CRP) and matrix metalloproteinases staining and high serum levels of high sensitive CRP (hs-CRP) and monocyte chemoattractant protein-1 (MCP-1) were observed in Ad5-CMV.p53-treated rabbits. However, a binary logistic regression model revealed that hs-CRP concentration rather than apoptosis rate played an independent role in plaque rupture with an odds ratio as 1.314 (95% CI: 1.041-1.657, P = 0.021), and there were high positive correlations between inflammatory biomarkers (hs-CRP or MCP-1) and apoptosis (R(2) = 0.761, and R(2) = 0.557, respectively, both P < 0.01). Intraplaque injection of p53 gene provides a safe and effective method for inducing plaque vulnerability in rabbits. The destabilizing effect of p53 overexpression is mediated mainly through apoptosis-enhanced inflammation rather than cell apoptosis itself.

Traditional Chinese medication Tongxinluo dose-dependently enhances stability of vulnerable plaques: a comparison with a high-dose simvastatin therapy.

This study was carried out to test the hypothesis that Tongxinluo (TXL) as a Chinese herbal medicine enhances stability of vulnerable plaque dose dependently via lipid-lowering and anti-inflammation effects, similar to a high-dose simvastatin therapy. After abdominal aortic balloon injury, 75 rabbits were fed a 1% cholesterol diet for 10 wk and were then divided into five groups for 8-wk treatment: control group, low-dose TXL group, moderate-dose TXL group, high-dose TXL group, and high-dose simvastatin group. At the end of week 16, an adenovirus containing p53 was injected into the abdominal aortic plaques. Two weeks later, plaque rupture was induced by pharmacological triggering. The incidence of plaque rupture in all treatment groups (14.3%, 7.1%, 7.7%, and 7.1%) was significantly lower than that in control group (73.3%; P>0.01). TXL dose-dependently lowered serum lipid levels and inhibited systemic inflammation. Corrected acoustic intensity and fibrous cap thickness of the aortic plaques were significantly increased, whereas plaque area, plaque burden, vulnerable index, and expression of oxidized low-density lipoprotein (ox-LDL) receptor 1, matrix metalloproteinase 1 (MMP-1), MMP-3, tissue inhibitor of MMP 1, and NF-kappaB in plaques were markedly reduced in all treatment groups when compared with the control group. Similar to high-dose simvastatin group, high-dose TXL group exhibited a low serum level of low-density lipoprotein cholesterol and ox-LDL, a low expression level of systemic and local inflammatory factors and a low plaque vulnerability index, with no differences in the incidence of plaque rupture among all treatment groups. TXL dose-dependently enhances the stability of vulnerable plaques and prevents plaques from rupture. Simvastatin and TXL offer similar protection in terms of lipid-lowering, anti-inflammation, and antioxidation effects.

Quantification of regional volume and systolic function of the left ventricle by real-time three-dimensional echocardiography.

Real-time three-dimensional (3D) echocardiography (RT-3DE) provides a unique technique to evaluate left ventricular regional function in a 3D format. We aimed to explore whether the left ventricular segmental volume and systolic function is uniform and to establish normal values of volume and systolic function parameters of 16 regions in healthy subjects. RT-3DE was performed in 41 normal subjects and four-dimensional (4D)-left ventricle (LV) analysis software and a TomTec workstation were used to analyze data for regional end-diastolic volume (EDV(R)), regional end-systolic volume (ESV(R)), regional stroke volume (SV(R)), regional ejection fraction (EF(R)), ratio of SV(R) to global SV (SV(R/G)) and ratio of SV(R) to global EDV (EF(R/G)). All regional volume and systolic function parameters were not uniform among the left ventricular walls. They all increased in the order of inferior, posterior, lateral, septal, anterior and antero-septal walls with an increasing trend from the apical, middle to basal segments. The systolic function (EF(R), SV(R/G) and EF(R/G)) of the anterior and antero-septal walls was significantly higher than that of the lateral, inferior and posterior walls. And the intra- and interobserver variability for EDV(R), ESV(R), SV(R/G) and EF(R/G) ranged from 2.9% to 5.8%. In conclusion, the regional volume and systolic function of the left ventricle is not uniform and, therefore, a normal left ventricle cannot be regarded as a symmetric model for assessing the regional systolic function. This information may improve the accuracy of RT-3DE techniques in the assessment of the left ventricular regional function. (E-mail: zhangyun@sdu.edu.cn and yaogh@yahoo.com).

[Impact of gender on in-hospital death in hospitalized patients with acute myocardial infarction].

OBJECTIVE: To investigate whether gender is an independent predictor of in-hospital death in hospitalized patients with acute myocardial infarction (AMI). METHODS: This retrospective study compared baseline characteristics, therapeutic approaches and the occurrence rate of angina pectoris, reinfarction, heart failure and death during hospitalization between 1501 male and 635 female hospitalized patients with AMI. Multivariate logistic regression analysis was performed to identify risk factors predicting in-hospital death. RESULTS: In-hospital death rate was significantly higher in female than male patients with AMI (11.7% vs. 6.3%, P < 0.01). Female patients with AMI were significantly older than male patients [(67.8 +/- 9.2) years vs. (61.1 +/- 11.9) years, P < 0.01] had a higher incidence of hypertension (52.1% vs. 41.1%, P < 0.01), diabetes mellitus (35.4% vs. 17.3%, P < 0.01), cardiac function > or = Killip class III (11.7% vs. 5.1%, P < 0.01) and TC > 4.68 mmol/L (71.3% vs. 55.0%, P < 0.01). Cigarette smoking, however, was more common in males than in females (69.4% vs. 15.7%, P < 0.01). Reperfusion therapy within the first 24 hours after symptom onset, beta-blockers and statins use during hospitalization were significantly fewer in females compared with males (22.2% vs. 31.5%, P < 0.01; 64.6% vs. 71.2%, P = 0.003; 43.1% vs. 48.0%, P = 0.041, respectively). An increased mortality was demonstrated in females during the hospitalization phase of AMI (11.7% vs. 6.3%, P < 0.01). The results of logistic regression demonstrated that age, diabetes mellitus, hypertension, Killip classification of cardiac function, administration of reperfusion therapy and beta receptor blockers use were significant predictors of in-hospital death in patients with AMI, with odds ratios being 1.06 (95% CI: 1.04 - 1.08), 1.96 (95% CI: 1.32 - 2.90), 1.80 (95% CI: 1.25 - 2.58), 2.86 (95% CI: 2.35 - 3.48), 0.44 (95% CI: 0.30 - 0.66) and 0.51 (95% CI: 0.36 - 0.74), respectively. CONCLUSIONS: The in-hospital mortality of females is significantly higher than that of males in this patient cohort. Older age, higher risk factor rates, less reperfusion therapy and beta-blockers use contributed to the higher in-hospital mortality in female patients with AMI compared to males.

Ezetimibe prevents myocardial remodeling in an obese rat model by inhibiting inflammation.

Inflammation plays an important role in the development of many obesity-related diseases. This study aimed to investigate the effect of ezetimibe on inflammation and myocardial remodeling in obese rats. A rat model of obesity was established, and myocardial damage was examined by transmission electron microscopy and Masson staining. Twenty obese rats were divided into two groups (n=10): obese group and ezetimibe group. Ten SD rats were used as controls. Western blot was performed to monitor the expression of P-p38MAPK and interleukin (IL)-6. Immunohistochemical staining was used to monitor the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. In the obese rats group, we observed increased inflammatory factors and myocardial hypertrophy. In contrast, the ezetimibe group exhibited decreased expression of inflammatory factors and an improvement in myocardial remodeling compared to the obese group. Mechanistically, we found that ezetimibe decreased P-p38MAPK, IL-6, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 levels in the hearts of the obese rats. Taken together, these results indicate that ezetimibe may improve myocardial remodeling in obese rats by inhibiting inflammation.