G-protein-coupled receptor kinase 4 causes renal angiotensin II type 2 receptor dysfunction by increasing its phosphorylation.

Activation of the angiotensin II type 2 receptor (AT2R) induces diuresis and natriuresis. Increased expression or/and activity of G-protein-coupled receptor kinase 4 (GRK4) or genetic variants (e.g., GRK4γ142V) cause sodium retention and hypertension. Whether GRK4 plays a role in the regulation of AT2R in the kidney remains unknown. In the present study, we found that spontaneously hypertensive rats (SHRs) had increased AT2R phosphorylation and impaired AT2R-mediated diuretic and natriuretic effects, as compared with normotensive Wistar-Kyoto (WKY) rats. The regulation by GRK4 of renal AT2R phosphorylation and function was studied in human (h) GRK4γ transgenic mice. hGRK4γ142V transgenic mice had increased renal AT2R phosphorylation and impaired AT2R-mediated natriuresis, relative to hGRK4γ wild-type (WT) littermates. These were confirmed in vitro; AT2R phosphorylation was increased and AT2R-mediated inhibition of Na+-K+-ATPase activity was decreased in hGRK4γ142V, relative to hGRK4γ WT-transfected renal proximal tubule (RPT) cells. There was a direct physical interaction between renal GRK4 and AT2R that was increased in SHRs, relative to WKY rats. Ultrasound-targeted microbubble destruction of renal GRK4 decreased the renal AT2R phosphorylation and restored the impaired AT2R-mediated diuresis and natriuresis in SHRs. In vitro studies showed that GRK4 siRNA reduced AT2R phosphorylation and reversed the impaired AT2R-mediated inhibition of Na+-K+-ATPase activity in SHR RPT cells. Our present study shows that GRK4, at least in part, impairs renal AT2R-mediated diuresis and natriuresis by increasing its phosphorylation; inhibition of GRK4 expression and/or activity may be a potential strategy to improve the renal function of AT2R.

Prasugrel or ticagrelor relative to clopidogrel in triple-antiplatelet treatment combined with glycoprotein IIb/IIIa inhibitor for patients with STEMI undergoing PCI: a meta-analysis.

BACKGROUND: For patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI), the efficacy and safety of novel P2Y12 antagonists, including prasugrel or ticagrelor, has not been established relative to that of the clopidogrel-based triple-antiplatelet treatments (TAPTs; in combination with glycoprotein IIb/IIIa inhibitor). The present meta-analysis evaluated the efficacy and safety of prasugrel- or ticagrelor-based TAPTs relative to that of clopidogrel TAPTs in patients with STEMI undergoing PCI. METHODS: The databases PubMed, Embase, and Cochrane's Library were systematically searched for relevant randomized controlled trials concerning prasugrel or ticagrelor (test) relative to clopidogrel (control). Depending on heterogeneity, studies were pooled with a random effects or a fixed effects model. Outcomes of blood flow after PCI were evaluated, including TIMI (thrombolysis in myocardial infarction), bleeding events, and major adverse cardiovascular events (MACEs). RESULTS: Seven studies comprising 11,874 patients conformed to the inclusion criteria. The pooled results with the fixed effects model indicated that after PCI patients in the prasugrel or ticagrelor groups were as likely as those treated with clopidogrel to achieve TIMI grade 3 flow or experience bleeding events. However, compared with the control, the test groups had significantly less risk of MACE (OR: 0.81, 95% CI: 0.70-0.94, P = 0.004), especially at the 1-year follow-up (OR: 0.79, 95% CI: 0.66-0.95, P = 0.01). CONCLUSIONS: A prasugrel- or ticagrelor-based TAPT may reduce the rate of MACEs, without increasing bleeding in STEMI patients undergoing PCI. However, due to the limited RCT studies and variations in study weight, results of this meta-analysis should be confirmed in a large RCT with adequate sample size and follow-up duration.

Resveratrol attenuates high glucose-induced endothelial cell apoptosis via mediation of store-operated calcium entry.

The aim of this study was to evaluate the influence of resveratrol on HG-induced calcium entry in islet microvascular (MS-1) endothelial cells. MS-1 cells were pretreated with resveratrol or 2-APB (an inhibitor of store-operated calcium entry) and then incubated with high glucose. Cell viability was determined using the cell counting kit-8 method. Reactive oxygen species, endothelial apoptosis, and NO production were detected by DHE probe, TUNEL detection, and nitrate reductase assay kit. Protein levels of SOCE were detected by western blotting. Pretreatment with resveratrol significantly attenuated HG-induced endothelial apoptosis and improved cell viability. However, pretreatment with resveratrol and 2-APB abolished this effect, suggesting that the attenuation of HG-induced apoptosis by resveratrol may be associated with SOCE. Subsequent analyses indicated that HG induced the SOCE-related proteins, including TRPC1, Orai1, and Stim1. These results suggest that resveratrol pretreatment is associated with relieved HG-induced endothelial apoptosis at least partly via inhibition of SOCE-related proteins.

FGF21 represses cerebrovascular aging via improving mitochondrial biogenesis and inhibiting p53 signaling pathway in an AMPK-dependent manner.

Cerebrovascular aging has a high relationship with stroke and neurodegenerative disease. In the present study, we evaluated the influence of fibroblast growth factor 21 (FGF21) on angiotensin (Ang II)-mediated cerebrovascular aging in human brain vascular smooth muscle cells (hBVSMCs). Ang II induced remarkable aging-phenotypes in hBVSMCs, including enhanced SA-ß-gal staining and NBS1 protein expression. First, we used immunoblotting assay to confirm protein expression of FGF21 receptor (FGFR1) and the co-receptor ß-Klotho in cultured hBVSMCs. Second, we found that FGF21 treatment partly prevented the aging-related changes induced by Ang II. FGF21 inhibited Ang II-enhanced ROS production/superoxide anion levels, rescued the Ang II-reduced Complex IV and citrate synthase activities, and suppressed the Ang II-induced meprin protein expression. Third, we showed that FGF21 not only inhibited the Ang II-induced p53 activation, but also blocked the action of Ang II on Siah-1-TRF signaling pathway which is upstream factors for p53 activation. At last, either chemical inhibition of AMPK signaling pathway by a specific antagonist Compound C or knockdown of AMPKα1/2 isoform using siRNA, successfully abolished the anti-aging action of FGF21 in hBVSMCs. These results indicate that FGF21 protects against Ang II-induced cerebrovascular aging via improving mitochondrial biogenesis and inhibiting p53 activation in an AMPK-dependent manner, and highlight the therapeutic value of FGF21 in cerebrovascular aging-related diseases such as stroke and neurodegenerative disease.

Triglycerides are Independently Associated with Atherosclerosis in Elderly Chinese Patients.

BACKGROUND: The aim of this study was to investigate the relationship between serum triglycerides (TG) levels and atherosclerosis and to explore its predicated value for atherosclerosis in elderly Chinese population. METHODS: A total of 593 elderly patients (age ≥ 60) were included in this cross-sectional study. Their clinical and biochemical characteristics were detected. Patients were divided into two groups: with atherosclerosis and without. The risk factors of atherosclerosis were explored by binary logistic regression analysis. RESULTS: The serum concentrations of TG were 1.72 ± 1.30 and 1.43 ± 0.88 mmol/L in patients with and without atherosclerosis, respectively. Binary logistic regression analysis showed that the significant risk factors were age (p = 0.000, OR = 1.094), TG (p = 0.008, OR = 1.315), type 2 diabetes (p = 0.042, OR = 1.499), and HTN (p = 0.006, OR = 1.724). The risk of atherosclerosis significantly increased in patients with TG > 1.3 mmol/L. After adjusting for different clinical parameters, the risk of atherosclerosis still significantly increased in patients with TG > 1.3 mmol/L. CONCLUSIONS: There was a strong and independent association between TG and atherosclerosis in elderly Chinese population, and TG > 1.3 mmol/L indicated a great increased risk of atherosclerosis.

Association Between Serum Cystatin C and High Blood Pressure (HBP): A Cross-Sectional Study of an Elder Chinese Type 2 Diabetic Population.

BACKGROUND: The aim of this study was to investigate the relationship between serum CysC levels and high blood pressure (HBP) and to explore its diagnostic value for HBP in elder type 2 diabetic (T2D) population. METHODS: A total of 369 elder T2D patients (age > 60) were included in this cross-sectional study. Their clinical and biochemical characteristics were detected. Patients were divided into two groups: with HBP and without. The risk factors of HBP were explored by binary logistic regression analysis. RESULTS: The serum concentrations of CysC were 1.08 ± 0.42 and 0.90 ± 0.21 mg/L in patients with and without HBP, respectively. Binary logistic regression analysis showed that the significant risk factors were CysC (p = 0.000, OR = 16.977), systolic blood pressure (p = 0.000, OR = 1.087), and diabetes duration (p = 0.000, OR = 1.289). The prevalence of HBP increased with CysC (p < 0.05), and the prevalence of HBP in patients with CysC ≥ 1.2 mg/L was much higher than the other three quartile groups. The risk of HBP dramatically increased in patients with cystatin C ≥ 1.2 mg/L (OR = 1.601, 95% confidence interval 1.239 - 2.069, p = 0.000). After adjusting for gender, age, and diabetes duration, its OR still remained 1.633 (95% confidence interval 1.181 - 2.257, p = 0.003). CONCLUSIONS: There was a strong and independent association between CysC and HBP in elder diabetic population, and cystatin C ≥ 1.2 mg/L indicated a great increased risk of HBP.

WITHDRAWN: Specific antigen vaccination modulates memory B cell activities.

The manuscript was withdrawn by the Author.

Antigen-specific immunotherapy regulates B cell activities in the intestine.

Mature B cells (BCs) express CD23 and B cell receptors. Whether activation of CD23 and B cell receptors has different effects on BC activities is unclear. This study aims to investigate the mechanism by which the specific antigen immunotherapy regulates the activation of BCs in the skewed Th2 responses. Mice were sensitized to ovalbumin. The specific antigen vaccination (SAV) at graded doses was employed to modulate the activities of BCs in which the expression of IL-10, IgE, matrix metalloproteinase-9 (MMP9), CD23, and serum soluble CD23 by BCs was evaluated. The immune regulatory effect of BCs primed by lower or higher SAV doses was observed with an adoptive transfer mouse experiment. SAV activated CD23 to produce IL-10 in BCs at lower doses. The higher doses of SAV increased the expression of MMP9 in BCs that reduced the amounts of CD23 in BCs and increased the serum levels of soluble CD23, which was abrogated by the pretreatment with MMP9 inhibitor. Adoptively transfer with BCs primed by lower doses of SAV inhibited the ongoing antigen-specific Th2 responses whereas the BCs primed by higher doses of SAV exacerbated the ongoing Th2 responses. Exposure to specific antigens at optimal doses can activate BCs to produce IL-10 to suppress the skewed antigen-specific Th2 responses. The antigen doses of SAV higher than the optimal doses may promote the production of soluble CD23 to exacerbate the ongoing immune responses.

Fibroblast growth factor 21 protects against high glucose induced cellular damage and dysfunction of endothelial nitric-oxide synthase in endothelial cells.

AIMS: Fibroblast growth factor 21 (FGF21) is a powerful endocrine hormone modulating glucose and lipid metabolism and represents a promising drug for type 2 diabetes. The present study was to determine the effect of FGF21 on high glucose-induced damage and dysfunction in endothelial cells. METHODS: The protein expression of ß-klotho was examined in human umbilical vein endothelial cell (HUVECs) using immunofluorescence and Western blotting. HUVECs were cultured in medium with normal glucose (NG), high glucose (HG) and HG + FGF21 (30 nM). Cell viability, migration, reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase, nitric oxide (NO) production, intracellular cyclic guanosine monophosphate (cGMP) and endothelial nitric oxide synthase (eNOS) phosphorylation at Ser-1177/Ser-633 sites were measured. RESULTS: ß-klotho, the anchor protein of FGF21, is expressed in HUVECs. Administration of FGF21 prevented HG-induced impairment of cell viability, migration, oxidant stress, NO production and intracellular cGMP levels in HUVECs. FGF21 also rescued HG-induced decrease of eNOS phosphorylation at Ser-1177 and Ser-633. HG and FGF21 had no effects on eNOS phosphorylation at Ser-617 and Thr-495. Inhibition of AMP-activated protein kinase (AMPK), but not Akt or Ca(2+)/calmodulin-dependent protein kinase II, abolished the protective effect of FGF21 on eNOS phosphorylation at Ser-1177. The protective effect of FGF21 on eNOS phosphorylation at Ser-633 was also abolished by inhibition of AMPK but not by Akt or cAMP-dependent protein kinase A. CONCLUSION: Our results provide the first evidence that FGF21 protects against high glucose induced cell damage and eNOS dysfunction in an AMPK-dependent manner in HUVECs, and suggest that FGF21 may be a promoting therapeutic agent for vascular complications in diabetes.

BRD2 protects the rat H9C2 cardiomyocytes from hypoxia­reoxygenation injury by targeting Nrf2/HO­1 signaling pathway.

Myocardial ischemia-reperfusion (I/R) injury is a common complication of acute myocardial infarction following percutaneous coronary intervention, but there are currently no effective pharmacological targets for adjuvant therapy due to a lack of knowledge of I/R injury mechanisms in cardiomyocytes. To evaluate the effects of hypoxia-reoxygenation on the plasma proteome of cardiomyocytes and prospective therapeutic targets, five sets of H9C2 cardiomyocytes from rats were cultured under various hypoxic circumstances. Using Cell Counting Kit-8 (CCK8) and lactose dehydrogenase (LDH) release assays, the cell viability and LDH release of H9C2 cells were analyzed. Proteome sequencing was then performed on cardiomyocytes to show the quantitative protein changes during the I/R injury process. After hypoxia/reoxygenation, bromodomain-containing protein 2 (BRD2) expression was evaluated. After administering the BRD2 inhibitor dBET1, the expression of nuclear factor erythroid 2-related factor 2/haem oxygenase-1 (Nrf2/HO-1) was identified. The results showed that in the group exposed to 4 h of hypoxia followed by 4 h of reoxygenation (H/R4), the cell survival rate was dramatically reduced, although the apoptotic rate and LDH were much higher than in the normal oxygen group. In addition, the expressions of 2,325 proteins differed considerably between these two groups, with 128 upregulated and 122 downregulated proteins being discovered in the H/R4 group. After 4 h of reoxygenation, the BRD2 expression was increased. Following the addition of dBET1 to suppress BRD2, the expression of Nrf2/HO-1 was reduced, but the rate of apoptosis increased. In conclusion, through the Nrf2/HO-1 signaling pathway, BRD2 protects cardiomyocytes from damage caused by hypoxia/reoxygenation. This may have implications for novel treatment targets to minimize I/R damage to the myocardium.

Predictive value of acoustic cardiography for post-PCI early ventricular remodeling in acute myocardial infarction.

Acoustic cardiography is a completely new technology, it has great advantages in the rapid diagnosis of cardiovascular diseases. The purpose of this study was to investigate the clinical value of the fourth heart sound (S4), cardiac systolic dysfunction index (SDI), and the cardiac cycle time-corrected electromechanical activation time (EMATc) in the prediction of post-percutaneous coronary intervention (PCI) early ventricular remodeling (EVR) in patients with acute myocardial infarction (AMI). We recruited 161 patients with AMI of 72-h post-PCI, including 44 EVR patients with left ventricular ejection fraction (LVEF) < 50% and 117 Non-EVR patients (normal left ventricular systolic function group, LVEF ≥ 50%). EMATc, S4, and SDI were independent risk factors for post-PCI early ventricular remodeling in patients with AMI [S4 (OR 2.860, 95% CI 1.297-6.306, p = 0.009), SDI (OR 4.068, 95% CI 1.800-9.194, p = 0.001), and EMATc (OR 1.928, 95% CI 1.420-2.619, p < 0.001)]. The area under the receiver operating characteristic curve for EMATc was 0.89, with an optimal cutoff point of 12.2, EMATc had a sensitivity of 80% and a specificity of 83%. By contrast, an optimal cutoff point of 100 pg/ml, Serum brain natriuretic peptide had a sensitivity of 46% and a specificity of 83%. Our findings suggest the predictive value of EMATc for the occurrence of EVR in these patients was also identified; EMATc may be a simple, quick, and effective way to diagnose EVR after AMI.

Selenium deficiency causes hypertension by increasing renal AT1 receptor expression via GPx1/H2O2/NF-κB pathway.

Epidemiological studies show an association between low body selenium and the risk of hypertension. However, whether selenium deficiency causes hypertension remains unknown. Here, we report that Sprague-Dawley rats fed a selenium-deficient diet for 16 weeks developed hypertension, accompanied with decreased sodium excretion. The hypertension of selenium-deficient rats was associated with increased renal angiotensin II type 1 receptor (AT1R) expression and function that was reflected by the increase in sodium excretion after the intrarenal infusion of the AT1R antagonist candesartan. Selenium-deficient rats had increased systemic and renal oxidative stress; treatment with the antioxidant tempol for 4 weeks decreased the elevated blood pressure, increased sodium excretion, and normalized renal AT1R expression. Among the altered selenoproteins in selenium-deficient rats, the decrease in renal glutathione peroxidase 1 (GPx1) expression was most prominent. GPx1, via regulation of NF-κB p65 expression and activity, was involved in the regulation of renal AT1R expression because treatment with dithiocarbamate (PDTC), an NF-κB inhibitor, reversed the up-regulation of AT1R expression in selenium-deficient renal proximal tubule (RPT) cells. The up-regulation of AT1R expression with GPx1 silencing was restored by PDTC. Moreover, treatment with ebselen, a GPX1 mimic, reduced the increased renal AT1R expression, Na+-K+-ATPase activity, hydrogen peroxide (H2O2) generation, and the nuclear translocation of NF-κB p65 protein in selenium-deficient RPT cells. Our results demonstrated that long-term selenium deficiency causes hypertension, which is due, at least in part, to decreased urine sodium excretion. Selenium deficiency increases H2O2 production by reducing GPx1 expression, which enhances NF-κB activity, increases renal AT1R expression, causes sodium retention and consequently increases blood pressure.

A novel method of augmenting gene expression and angiogenesis in the normal and ischemic canine myocardium.

This study presents a novel method that direct intramyocardial injection of low-dose plasmid DNA and microbubbles combined with insonation could further augment gene expression in normal and ischemic canine myocardium. Plasmids encoding enhanced green fluorescent protein (pEGFP) and hepatocyte growth factor (pHGF) (500 µg) were individually mixed with 0.5 ml of microbubble solution (MB) and injected into the normal or acute ischemic canine myocardium. The dogs in the plasmid + MB/US group underwent insonation (US). Other dogs were randomly divided into three treatment groups: plasmid and insonation, plasmid and MB injection, and plasmid injection only. The EGFP and HGF mRNA expressions were assessed in the myocardium at the injection site and at sites 0.5 and 1 cm remote from the injection site. Compared to plasmid transfer alone, a mean 13.4-fold enhancement of gene expression was achieved in the EGFP + MB/US group at 48 h (p < 0.01). HGF mRNA expression in ischemic zones was markedly elevated after 28 days, with a mean 9.0-fold enhancement in the HGF + MB/US group (p < 0.01). EGFP protein expression was detected in the normal myocardium at 1 cm remote from the injection site in the EGFP + MB/US group. Similarly, HGF protein expression was detected in the ischemic myocardium at 0.5 cm remote from the injection site in the HGF + MB/US group. These findings indicate that the radius of gene expression was partly extended in the two plasmid + MB/US groups. The capillary density increased from 20.9 ± 5.3/mm(2) in control myocardial infarction dogs without treatment to 126.7 ± 38.2/mm(2) in the HGF + MB/US group (p < 0.01). Taken together, the present data demonstrate that direct intramyocardial injection of an angiogenic gene and microbubbles combined with insonation can augment gene expression and angiogenesis. Consequently, this strategy may be a useful tool for gene therapy of ischemic heart disease.

A visible, targeted high-efficiency gene delivery and transfection strategy.

BACKGROUND: To enhance myocardial angiogenic gene expression, a novel gene delivery strategy was tested. Direct intramyocardial injection of an angiogenic gene with microbubbles and insonation were applied in a dog animal model. Dogs received one of the four different treatments in conjunction with either the enhanced green fluorescence protein (EGFP) gene or the hepatocyte growth factor (HGF) gene: gene with microbubbles (MB) and ultrasound (US); gene with US; gene with MB; or the gene alone. RESULTS: Distribution of MB and the gene in the myocardium was visualized during the experiment. Compared with the EGFP gene group, an average 14.7-fold enhancement in gene expression was achieved in the EGFP+MB/US group (P < 0.01). Compared with the HGF gene group, an average 10.7-fold enhancement in gene expression was achieved in the HGF+MB/US group (P < 0.01). In addition, capillary density increased from 20.8 ± 3.4/mm2 in the HGF gene group to 146.7 ± 31.4/mm2 in HGF+MB/US group (P < 0.01). CONCLUSIONS: Thus, direct intramyocardial injection of an angiogenic gene in conjunction with microbubbles plus insonation synergistically enhances angiogenesis. This method offers an observable gene delivery procedure with enhanced expression efficiency of the delivered gene.

Bacteriological differences between COPD exacerbation and community-acquired pneumonia.

OBJECTIVE: To study the differences in pathogen distribution and antibiotic susceptibility between patients with COPD exacerbation and patients with community-acquired pneumonia, and develop guidance for antibiotic treatment of those conditions. METHODS: We retrospectively analyzed the medical records of 586 COPD-exacerbation patients and 345 community-acquired-pneumonia patients from January 2007 to December 2008, including sputum culture results, antibiotic susceptibilities of the microorganisms, and clinical characteristics. RESULTS: 276 (47%) of the COPD-exacerbation patients, and 183 (53%) of the community-acquired-pneumonia patients had a positive sputum culture. In order, the most common pathogens in the COPD-exacerbation patients were Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Acinetobacter baumannii, and Haemophilus influenzae. The most common pathogens in the community-acquired-pneumonia patients were Streptococcus pneumoniae, H. influenzae, K. pneumoniae, S. aureus, and E. coli. CONCLUSIONS: P. aeruginosa was the most common pathogen in our patients with COPD exacerbation, and S. pneumoniae was the most common in our patients with community-acquired pneumonia. P. aeruginosa is especially common in the patients with serious or extremely serious COPD.

Protective effects of AMP-activated protein kinase in the cardiovascular system.

Cardiovascular diseases remain the leading cause of mortality worldwide. Recent studies of AMP-activated protein kinase (AMPK), a highly conserved sensor of cellular energy status, suggest that there might be therapeutic value in targeting the AMPK signaling pathway. AMPK is found in most mammalian tissues, including those of the cardiovascular system. As cardiovascular diseases are typically associated with blood flow occlusion and blood occlusion may induce rapid energy deficit, AMPK activation may occur during the early phase upon nutrient deprivation in cardiovascular organs. Therefore, investigation of AMPK in cardiovascular organs may help us to understand the pathophysiology of defence mechanisms in these organs. Recent studies have provided proof of concept for the idea that AMPK is protective in heart as well as in vascular endothelial and smooth muscle cells. Moreover, dysfunction of the AMPK signalling pathway is involved in the genesis and development of various cardiovascular diseases, including atherosclerosis, hypertension and stroke. The roles of AMPK in the cardiovascular system, as they are currently understood, will be presented in this review. The interaction between AMPK and other cardiovascular signalling pathways such as nitric oxide signalling is also discussed.

Identification of potential molecular mechanisms and small molecule drugs in myocardial ischemia/reperfusion injury.

Myocardial ischemia/reperfusion (MI/R) injury is a complex phenomenon that causes severe damage to the myocardium. However, the potential molecular mechanisms of MI/R injury have not been fully clarified. We identified potential molecular mechanisms and therapeutic targets in MI/R injury through analysis of Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were found between MI/R injury and normal samples, and overlapping DEGs were found between GSE61592 and GSE67308. Gene Ontology (GO) and pathway analysis were performed for overlapping DEGs by Database for Annotation, Visualization and Integration Discovery (DAVID). Then, a network of protein-protein interaction (PPI) was constructed through the Search Tool for the Retrieval of Interacting Genes (STRING) database. Potential microRNAs (miRNAs) and therapeutic small molecules were screened out using microRNA.org database and the Comparative Toxicogenomics database (CTD), respectively. Finally, we identified 21 overlapping DEGs related to MI/R injury. These DEGs were significantly enriched in IL-17 signaling pathway, cytosolic DNA-sensing pathway, chemokine signaling, and cytokine-cytokine receptor interaction pathway. According to the degree in the PPI network, CCL2, LCN2, HP, CCL7, HMOX1, CCL4, and S100A8 were found to be hub genes. Furthermore, we identified potential miRNAs (miR-24-3p, miR-26b-5p, miR-2861, miR-217, miR-4251, and miR-124-3p) and therapeutic small molecules like ozone, troglitazone, rosiglitazone, and n-3 polyunsaturated fatty acids for MI/R injury. These results identified hub genes and potential small molecule drugs, which could contribute to the understanding of molecular mechanisms and treatment for MI/R injury.

Resveratrol prevents hyperglycemia-induced endothelial dysfunction via activation of adenosine monophosphate-activated protein kinase.

Endothelial dysfunction secondary to persistent hyperglycemia plays a key role in the development of type 2 diabetic vascular disease. The aim of the present study was to examine the protective effect of resveratrol against hyperglycemia-induced endothelial dysfunction. In cultured human umbilical vein endothelial cells (HUVECs), resveratrol (10-100 microM) concentration dependently enhanced phosphorylation of endothelial nitric oxide synthesis (eNOS) at Ser1177 and nitric oxide (NO) production. In addition, resveratrol can increase the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) at Thr172 and suppress high glucose-induced generation of superoxide anion. In mouse aortic rings, resveratrol (1-100 microM) elicited endothelium-dependent vasodilatations and alleviated high glucose-mediated endothelial dysfunction. All these beneficial effects of resveratrol on the endothelium were abolished by pharmacological antagonism of AMPK by compound C. These results provide new insight into the protective properties of resveratrol against endothelial dysfunction caused by high glucose, which is attributed to the AMPK mediated reduction of superoxide level.

Identification of the molecular mechanisms associated with acute type A aortic dissection through bioinformatics methods.

Aortic dissection is characterized by the redirection of blood flow, which flows through an intimal tear into the aortic media. The purpose of this study was to find potential acute type A aortic dissection (AAAD)-related genes and molecular mechanisms by bioinformatics. The gene expression profiles of GSE52093 were obtained from Gene Expression Omnibus (GEO) database, including 7 AAAD samples and 5 normal samples. The differentially expressed genes (DEGs) were detected between AAAD and normal samples. The functional annotation and pathway enrichment analysis were conducted through the Database for Annotation, Visualization and Integration Discovery (DAVID). A protein-protein interaction network was established by the Search Tool for the Retrieval of Interacting Genes (STRING) software. The microRNAs (miRNAs) of these differentially expressed genes were predicted using database. Moreover, DEGs were analyzed in the comparative toxicogenomics (CTD) database to screen out the potential therapeutic small molecules. As a result, there were 172 DEGs identified in patients with AAAD. These DEGs were significantly enriched in 6 pathways, including cell cycle, oocyte meiosis, DNA replication, extracellular matrix-receptor interaction, and mineral absorption pathway. Notably, CDC20, CDK1, CHEK1, KIF20A, MCM10, PBK, PTTG1, RACGAP, and TOP2A were crucial genes with a high degree in the protein-protein interaction network. Furthermore, potential miRNAs (miR-301, miR-302 family, and miR-130 family) were identified. In addition, small molecules like azathioprine and zoledronic acid were identified to be potential drugs for AAAD.

Klotho attenuates isoproterenol-induced hypertrophic response in H9C2 cells by activating Na+/K+-ATPase and inhibiting the reverse mode of Na+/Ca2+-exchanger.

Cardiac hypertrophy plays a major role in heart failure and is related to patient morbidity and mortality. Calcium overloading is a main risk for cardiac hypertrophy, and Na+/K+-ATPase (NKA) has been found that it could not only regulate intracellular Na+ levels but also control the intracellular Ca2+ ([Ca2+]i) level through Na+/Ca2+-exchanger (NCX). Recent studies have reported that klotho could affect [Ca2+]i level. In this study, we aimed at exploring the role of klotho in improving isoproterenol-induced hypertrophic response of H9C2 cells. The H9C2 cells were randomly divided into control and isoproterenol (ISO) (10 µM) groups. Klotho protein (10 µg/ml) or NKAα2 siRNA was used to determine the changes in isoproterenol-induced hypertrophic response. The alterations of [Ca2+]i level were measured by spectrofluorometry. Our results showed that H9C2 cells which were treated with isoproterenol presented a higher level of [Ca2+]i and hypertrophic gene expression at 24 and 48 h compared with the control group. Moreover, the expressions of NKAα1 and NKAα2 were both increased in control and ISO groups after treating with klotho protein; meanwhile, the NKA activity was increased and NCX activity was decreased after treatment. Consistently, the [Ca2+]i level and hypertrophic gene expression were decreased in ISO group after klotho protein treatment. However, these effects were both prevented by transfecting with NKAα2 siRNA. In conclusion, these findings demonstrated that klotho inhibits isoproterenol-induced hypertrophic response in H9C2 cells by activating NKA and inhibiting the reverse mode of NCX and this effect may be associated with the upregulation of NKAα2 expression.