Downregulation of HHATL promotes cardiac hypertrophy via activation of SHH/DRP1.

HHATL, previously implicated in cardiac hypertrophy in the zebrafish model, has emerged as a prioritized HCM risk gene. We identified six rare mutations in HHATL, present in 6.94 % of nonsarcomeric HCM patients (5/72). Moreover, a decrease of HHATL in the heart tissue from HCM patients and cardiac hypertrophy mouse model using transverse aortic constriction was observed. Despite this, the precise pathogenic mechanisms underlying HHATL-associated cardiac hypertrophy remain elusive. In this study, we observed that HHATL downregulation in H9C2 cells resulted in elevated expression of hypertrophic markers and reactive oxygen species (ROS), culminating in cardiac hypertrophy and mitochondrial dysfunction. Notably, the bioactive form of SHH, SHHN, exhibited a significant increase, while the mitochondrial fission protein dynamin-like GTPase (DRP1) decreased upon HHATL depletion. Intervention with the SHH inhibitor RU-SKI 43 or DRP1 overexpression effectively prevented Hhatl-depletion-induced cardiac hypertrophy, mitigating disruptions in mitochondrial morphology and membrane potential through the SHH/DRP1 axis. In summary, our findings suggest that HHATL depletion activates SHH signaling, reducing DRP1 levels and thereby promoting the expression of hypertrophic markers, ROS generation, and mitochondrial dysfunction, ultimately leading to cardiac hypertrophy. This study provides additional compelling evidence supporting the association of HHATL with cardiac hypertrophy.

The association between erector spinae muscle content and chronic heart failure and its severity.

AIMS: Previous studies have shown a significant reduction in skeletal muscle content in patients with chronic heart failure (CHF). The present study focused on the erector spinae muscle (ESM) to determine whether ESM content is associated with the development and severity of CHF. METHODS AND RESULTS: A total of 652 patients were included in this trial for the study. According to the diagnostic criteria of CHF, 652 patients were divided into two groups, namely, the control group (268 patients) and the CHF group (384 patients). Meanwhile, to assess whether the ESM is associated with the severity of CHF, patients in the CHF group were divided into two groups according to left ventricular ejection fraction (LVEF) values: heart failure with preserved ejection fraction (HFpEF, LVEF ≥50%, 256 patients) and heart failure with reduced ejection fraction (HFrEF, LVEF ≤40%, 68 patients). Receiver operating curve analysis was performed to assess whether ESM content could predict CHF and determine its severity. Compared with the control group, the patients in the CHF group were older, the prevalence of coronary heart disease (CHD) and atrial fibrillation was higher, the colour ultrasound results showed that LVEF decreased significantly, and the left ventricular end-diastolic internal diameter and left ventricular end-systolic internal diameter increased significantly. Besides, patients in the CHF group had significantly lower ESM content, and ESM is an independent predictor of heart failure, with an odds ratio of 0.713 (CHF group vs. control group, 95% confidence interval 0.626-0.811, P < 0.001). Compared with the HFpEF group, the HFrEF group has a lower prevalence of CHD, LVEF decreased significantly, the left ventricular end-diastolic internal diameter and left ventricular end-systolic internal diameter increased significantly, also patients in the HFrEF group had significantly lower ESM content compared with patients in the HFpEF group, and ESM is an independent predictor of the severity of heart failure, with an odds ratio of 0.514 (HFrEF group vs. HFpEF group, 95% confidence interval (0.418-0.633, P < 0.05). The results of receiver operating curve analysis showed that the sensitivity and specificity of ESM content for the diagnosis of CHF were 65.6% and 71.6%, respectively, while the sensitivity and specificity of ESM content for predicting the severity of CHF were 47.1% and 89.1%, respectively. CONCLUSIONS: The ESM is of great value in predicting the onset and severity of CHF.

Integration of transcriptomic data identifies key hallmark genes in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) represents one of the most common inherited heart diseases. To identify key molecules involved in the development of HCM, gene expression patterns of the heart tissue samples in HCM patients from multiple microarray and RNA-seq platforms were investigated. METHODS: The significant genes were obtained through the intersection of two gene sets, corresponding to the identified differentially expressed genes (DEGs) within the microarray data and within the RNA-Seq data. Those genes were further ranked using minimum-Redundancy Maximum-Relevance feature selection algorithm. Moreover, the genes were assessed by three different machine learning methods for classification, including support vector machines, random forest and k-Nearest Neighbor. RESULTS: Outstanding results were achieved by taking exclusively the top eight genes of the ranking into consideration. Since the eight genes were identified as candidate HCM hallmark genes, the interactions between them and known HCM disease genes were explored through the protein-protein interaction (PPI) network. Most candidate HCM hallmark genes were found to have direct or indirect interactions with known HCM diseases genes in the PPI network, particularly the hub genes JAK2 and GADD45A. CONCLUSIONS: This study highlights the transcriptomic data integration, in combination with machine learning methods, in providing insight into the key hallmark genes in the genetic etiology of HCM.

Coronary flow reserve and microcirculatory resistance in patients with coronary tortuosity and without atherosclerosis.

OBJECTIVE: Coronary tortuosity may affect epicardial coronary arterial blood flow. This study aimed to investigate the effect of coronary tortuosity on coronary flow reserve and the coronary microcirculation in patients without apparent coronary atherosclerosis. METHODS: Prospective patients (n = 8, 3 men, mean age: 58 ± 6.0 years) with coronary tortuosity and without apparent coronary atherosclerosis were enrolled. Coronary tortuosity was defined by the finding of ≥three bends (defined as a ≥45° change in vessel direction) along the main trunk of the left anterior descending artery or left circumflex artery. Coronary flow reserve and the index of microcirculatory resistance were measured by the thermodilution technique. RESULTS: A total of eight coronary arteries with coronary tortuosity were analyzed. The mean fractional flow reserve was 0.98 ± 0.007. The mean coronary flow reserve was 1.5 ± 0.3, which is much lower than that in the normal coronary artery as reported in the literature. The mean index of microcirculatory resistance was 26.7 ± 2.3, which is much higher than that in the normal coronary artery. CONCLUSIONS: Coronary tortuosity is associated with decreased coronary flow reserve and an increased index of microcirculatory resistance.Trial registration: This study is registered at the Chinese Clinical Trial Registry, NCT No: ChiCTR2000033671.

MSCs Contribute to the Conversion of Ly6Chigh Monocytes into Ly6Clow Subsets under AMI.

BACKGROUND: Ly6Chigh monocytes are inflammatory cells that accumulate in an infarcted myocardium, and Ly6Clow monocytes are believed to be reparative and curb myocardial remodeling. NR4A1 is a novel target for modulating the inflammatory phenotype of monocytes during atherogenesis. OBJECTIVES: We aimed to investigate whether MSCs can contribute to the heterogeneity of Ly6Chigh monocytes differentiated into Ly6Clow monocytes and whether this regulation is related to nuclear receptor NR4A1. METHODS: Ly6Chigh/low monocytes were first cocultured with MSCs. C57BL/6CX3CR1-/- mice and C57BL/6 wild-type mice were then used to construct AMI models, and survival functions in the two groups were further compared. Ly6Chigh/low monocytes in circulation and in MI tissue of C57BL/6CX3CR1-/- AMI mice with or without MSC transplantation were determined by flow cytometry at day 1 and day 3. NR4A1 expression was further determined by Western blot. Apoptosis of cardiac myocytes in the infarct border zone at day 3 and day 7 was identified by TUNEL kits. Angiogenesis in the AMI heart at day 7 and day 21 was determined through immunohistochemistry by CD31. RESULTS: We first demonstrated that the percentage of Ly6Clow monocytes increased greatly after 3 days of coculture with MSCs (12.8% ± 3.77% vs. 3.69% ± 0.74%, p < 0.001). The expression of NR4A1 in Ly6Chigh/low monocytes was also significantly elevated at that time (1.81 ± 0.46 vs. 0.43 ± 0.09, p < 0.001). Following AMI, the percentage of circulating Ly6Clow monocytes in C57BL/6CX3CR1-/- mice was significantly lower than that in C57BL/6 wild-type mice (4.36% ± 1.27% vs. 12.17% ± 3.81%, p < 0.001). The survival rate of C57BL/6CX3CR1-/- mice (25%) was significantly lower than that of C57BL/6 wild-type mice (56.3%) after AMI (χ 2 = 4.343, p = 0.037). After MSCs were transplanted, we observed a significant increase in Ly6Clow monocytes both in circulation (16.7% ± 3.67% vs. 3.22% ± 0.44%, p < 0.001) and in the MI heart (3.31% ± 0.69% vs. 0.42% ± 0.21%, p < 0.001) of C57BL/6CX3CR1-/- mice. Western blot analysis further showed that the expression level of NR4A1 in the MI hearts of C57BL/6CX3CR1-/- mice increased significantly under MSC transplantation (0.39 ± 0.10 vs. 0.11 ± 0.04, p < 0.001). We also found significantly decreased TUNEL+ cardiac myocytes (15.45% ± 4.42% vs. 22.78% ± 6.40%, p < 0.001) in mice with high expression levels of NR4A1 compared to mice with low expression levels. Meanwhile, we further identified increased capillary density in the infarct zones of mice with high expression levels of NR4A1 (0.193 ± 0.036 vs. 0.075 ± 0.019, p < 0.001) compared to mice with low expression levels 21 days after AMI. CONCLUSIONS: MSCs can control the heterogeneity of Ly6Chigh monocyte differentiation into Ly6Clow monocytes and further reduce inflammation after AMI. The underlying mechanism might be that MSCs contribute to the increased expression of NR4A1 in Ly6Chigh/low monocytes.

LncRNA-LUNAR1 Levels Are Closely Related to Coronary Collaterals in Patients with Chronic Total Coronary Occlusion.

Coronary collaterals can effectively improve myocardial blood supply to the area of CTO (chronic total coronary occlusion) and can, thus, reduce infarct size. LUNAR1(leukemia-induced noncoding activator RNA-1) is a specific LncRNA regulated by Notch signaling that not only can enhance the expression of IGFR-1 but also can promote angiogenesis and cell survival. Here, we investigated the relationship between LncRNA-LUNAR1 levels in peripheral plasma and the formation of coronary collaterals. In total, 172 patients with CTO were enrolled and followed up for 12 months. Coronary collaterals were scored according to the Rentrop scoring system. Preclinical tests of tube formation were used to address the mechanisms behind the association between LncRNA-LUNAR1 and development of collaterals. Clinical data and inflammatory factors, including comorbidity, CD14++CD16- monocytes, and CCL2 (chemokine motif ligand 2), were compared and analyzed. Real-time PCR was used to detect the expression of LncRNA-LUNAR1 in peripheral blood plasma. The Rentrop score was positively correlated with LncRNA-LUNAR1 levels in patients with CTO (R = 0.47, p < 0.001). Tube formation assay proved the direct association between LncRNA-LUNAR1 and development of collaterals (p = 0.011). The univariate Kaplan-Meier analysis revealed that patients with low LncRNA-LUNAR1 expression exhibited worse clinical outcomes than those with high LncRNA-LUNAR1 levels (p = 0.008). Receiver operating characteristic (ROC) curve and correlation analysis further confirmed that LncRNA-LUNAR1 expression was closely related to chronic inflammatory diseases, especially diabetes (area = 0.644, p = 0.001; 95% CI, 0.562-0.726). Furthermore, both CD14++CD16- monocytes (r = - 0.37; p < 0.001) and CCL2 levels (r = - 0.35; p < 0.001) negatively affected the expression of LncRNA-LUNAR1. LncRNA-LUNAR1 expression was positively correlated with coronary collaterals in patients with CTO. Inflammatory factors, including CD14++CD16- monocytes and CCL2, may be risk factors affecting LncRNA-LUNAR1 expression.

A novel LAMP2 p.G93R mutation associated with mild Danon disease presenting with familial hypertrophic cardiomyopathy.

BACKGROUND: Danon disease (DD) is an X-linked dominant multisystem disorder that is associated with cardiomyopathy, skeletal myopathy, and varying degrees of intellectual disability. It results from mutations in the lysosome-associated membrane protein 2 (LAMP2) gene. METHODS: Herein, a proband with a mild DD case presenting with a familial hypertrophic cardiomyopathy (HCM) phenotype and additional family members were evaluated. Exome sequencing and Sanger sequencing were performed to explore the genetic basis of DD in the proband. Segregation, in silico, and functional analyses were carried out to explore potential pathogenicity in the candidate mutation. RESULTS: Exome sequencing and Sanger sequencing identified one novel missense mutation (p.G93R) in the LAMP2 gene in the proband, and this mutation was also identified in three other family members. In silico analysis of LAMP2 predicted that the mutation causes a conformational change and subsequent protein destabilization. Furthermore, functional examination showed that mutation carriers have a significant reduction in LAMP2 expression, which supports that the mutation is pathogenic. Moreover, skewed X chromosome inactivation (XCI) was identified in one female mutation carrier, thus suggesting that skewed XCI may be the reason why this individual escaped the pathogenic influence of the mutation. CONCLUSION: These findings will aid in diagnosing DD patients carrying this LAMP2 mutation that presents with a HCM phenotype. Furthermore, this study illustrates the importance of utilizing a molecular diagnostic approach in HCM patients and is the first study to report a LAMP2 p.G93R mutation associated with mild DD and identify that XCI serves a protective role in DD etiology.

Safety and Efficacy of a New Renal Denervation Catheter in Hypertensive Patients in the Absent of Antihypertensive Medications: A Pilot Study.

AIM: The aim of present study was to determine the safety and efficacy of a new renal artery denervation system for treatment of hypertensive patients. METHODS: Hypertensive patients with mean office systolic blood pressure ≥150mmHg and ≤180mmHg or an average of 24-hour ambulatory systolic blood pressure ≥145mmHg and ≤170mmHg after stopping hypertensive medications for 2 weeks or more were enrolled to undergo renal denervation (RDN) using a new RDN system. Changes in office blood pressure and mean 24-hour ambulatory blood pressure and safety were assessed after 6 months. RESULTS: Fifteen patients underwent RDN and followed up for 6 months. At the 6-month follow-up, office systolic blood pressure decreased 11.5±9.9mmHg (P<0.01) and office diastolic blood pressure decreased 6.9±4.8mmHg (P<0.01); mean 24-hour ambulatory systolic blood pressure decreased 7.5±7.7mmHg (P<0.05) and mean 24-hour diastolic blood pressure decreased 3.3±4.7mmHg (P>0.05) compared to baseline values. There were no serious RDN-related adverse events during follow-up. CONCLUSION: Our results demonstrate that the new RDN system is safe and could significantly reduce blood pressure in hypertensive patients in the absence of antihypertensive medications. This trial is registered with ChiCTR1800017815.

Inverse opal substrate-loaded mesenchymal stem cells contribute to decreased myocardial remodeling after transplantation into acute myocardial infarction mice.

BACKGROUND: The two-dimensional incubation method is now the most commonly method for mesenchymal stem cell (MSC) production. however, gene expression and secretion of growth factors are relatively low; thus, the transplanted cells cannot be effectively utilized for potential clinical applications after acute myocardial infarction (AMI). OBJECTIVES: We aimed to investigate whether our newly made substrates of inverse opal with specific surface microstructures for MSC culturing can increase the viability of the cells and can contributes to decreased myocardial remodeling after transplanted to AMI mice. METHODS: The inverse opal structure is fabricated by the convenient bottom-up approach of the self-assembly of colloidal nanoparticles. Mouse-derived MSCs were then cultured on the substrates when expanded at different times to investigate the cell growth status including morphology. Then the inverse opal substrates loaded MSCs were transplanted to AMI mice, cardiomyocyte apoptosis and LV remodeling were further compared. To explore the possible mechanisms of curation, the secretions and viability of MSCs on substrates were determined using mice ELISA kits and JC-1 mitochondrial membrane potential assay kits respectively at normal and hypoxic conditions. RESULTS: 6 times expanded inverse opals allowed greatly the orderly growth of MSCs as compared to four (34% ± 10.6%) and two (20%±7.2%) times expanded as well as unexpanded (13%±4.1%) (P<0.001). Nearly 90% of MSCs showed orientation angle intervals of less than 30° when at the 6X expanded (89.6%±25%) compared to the percent of cells with 30°-60° (8.7%±2.6%) or ≥60° (1.7%±1.0%) orientation angle (P<0.001). After inverse opal loaded MSCs transplanted to AMI mice, greatly decreased apoptosis of cardiomyocytes (20.45%±8.64% vs.39.63%±11.71%, P<0.001) and infarction area (5.87±2.18 mm2 vs 9.31±3.11 mm2, P<0.001) were identified. In the end, the viability of inverse opal loaded MSCs determined by membrane potential (P<0.001) and the secretion of growth factors including VEGF-α, SDF-1 and Ang-1 (P<0.001) were both confirmed significantly higher than that of the conventional culture in petri dish. CONCLUSION: The structure of inverse opal can not only adjust the arrangement of MSCs but also contribute to its orientated growth. Inverse opal loaded MSCs transplantation extremely curbed myocardial remodeling, the underlying mechanisms might be the high viability and extremely higher secretions of growth factors of MSCs as devoted by this method.

Erythropoietin Attenuates Cardiac Dysfunction in Rats by Inhibiting Endoplasmic Reticulum Stress-Induced Diabetic Cardiomyopathy.

PURPOSE: Enhanced endoplasmic reticulum (ER) stress and down-regulated SERCA2a expression play crucial roles in diabetes. We aimed to verify whether erythropoietin (EPO) attenuates cardiac dysfunction by suppressing ER stress in diabetic rats. METHODS: Forty male SD rats were randomly divided into four groups: control, EPO-treated control, vehicle-treated diabetic, and EPO-treated diabetic groups. The animals in the EPO-treated control and diabetic groups were administered recombinant human EPO (1000 U/kg body weight) once per week for 12 weeks. RT-PCR and Western blotting assays were performed to detect the expression of 78-kDa glucose-regulated protein precursor (GRP78) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA2a). We cultured neonatal rat cardiomyocytes and investigated the protective effects of EPO against high glucose (HG)-induced apoptosis. Intracellular calcium levels were measured through confocal microscopy. RESULTS: We observed increased myocardial GRP78 expression and decreased myocardial SERCA2a expression in diabetic rats. EPO prevented the changes in GRP78, SERCA2a expression and cardiac dysfunction in diabetic rats. The levels of GRP78 protein were significantly reduced in EPO-treated diabetic rats compared with vehicle-treated diabetic rats (GRP78 protein 0.09 ± 0.03 vs. 0.54 ± 0.04, P < 0.01). The levels of the SERCA2a proteins were significantly increased in EPO-treated diabetic rats compared with vehicle-treated diabetic rats (SERCA2a protein 0.60 ± 0.05 vs. 0.13 ± 0.04, P < 0.01). A reduction in apoptosis was observed in the cardiomyocytes treated with 20 U/mL EPO compared with the cardiomyocytes cultured under HG conditions (apoptosis rate 18.9 ± 1.94 vs. 37.9 ± 1.59%, P < 0.01). CONCLUSIONS: This study demonstrates that EPO treatment improved the parameters of cardiac function following HG-induced injury by suppressing ER stress and inducing SERCA2a expression.

Investigation of Pathogenic Genes in Chinese sporadic Hypertrophic Cardiomyopathy Patients by Whole Exome Sequencing.

Hypertrophic cardiomyopathy (HCM) is a cardiovascular disease with high heterogeneity. Limited knowledge concerning the genetic background of nearly 40% HCM cases indicates there is a clear need for further investigation to explore the genetic pathogenesis of the disease. In this study, we undertook a whole exome sequencing (WES) approach to identify novel candidate genes and mutations associated with HCM. The cohort consisted of 74 unrelated patients with sporadic HCM (sHCM) previously determined to be negative for mutations in eight sarcomere genes. The results showed that 7 of 74 patients (9.5%) had damaging mutations in 43 known HCM disease genes. Furthermore, after analysis combining the Transmission and De novo Association (TADA) program and the ToppGene program, 10 putative genes gained priority. A thorough review of public databases and related literature revealed that there is strong supporting evidence for most of the genes playing roles in various aspects of heart development. Findings from recent studies suggest that the putative and known disease genes converge on three functional pathways: sarcomere function, calcium signaling and metabolism pathway. This study illustrates the benefit of WES, in combination with rare variant analysis tools, in providing valuable insight into the genetic etiology of a heterogeneous sporadic disease.

Effect of percutaneous renal sympathetic nerve radiofrequency ablation in patients with severe heart failure.

This study aimed to investigate the clinical feasibility and effects of percutaneous renal sympathetic nerve radiofrequency ablation in patients with heart failure. A total of 20 patients with heart failure were enrolled, aged from 47 to 75 years (63±10 years). They were divided into the standard therapy (n = 10), and renal nerve radiofrequency ablation groups (n = 10). There were 15 males and 5 female patients, including 8 ischemic cardiomyopathy, 8 dilated cardiomyopathy, and 8 hypertensive cardiopathy. All of the patients met the criteria of New York Heart Association classes III-IV cardiac function. Patients with diabetes and renal failure were excluded. Percutaneous renal sympathetic nerve radiofrequency ablation was performed on the renal artery wall under X-ray guidance. Serum electrolytes, neurohormones, and 24 h urine volume were recorded 24 h before and after the operation. Echocardiograms were performed to obtain left ventricular ejection fraction at baseline and 6 months. Heart rate, blood pressure, symptoms of dyspnea and edema were also monitored. After renal nerve ablation, 24 h urine volume was increased, while neurohormone levels were decreased compared with those of pre-operation and standard therapy. No obvious change in heart rate or blood pressure was recorded. Symptoms of heart failure were improved in patients after the operation. No complications were recorded in the study. Percutaneous renal sympathetic nerve radiofrequency ablation may be a feasible, safe, and effective treatment for the patients with severe congestive heart failure.

Tissue kallikrein is related to the severity of coronary artery disease.

BACKGROUND: The impairment of the tissue kallikrein (KLK1)-kinin system (KKS) may result in atheroma development. However, it remains unclear if the KKS correlates with coronary artery disease (CAD). METHODS: KLK1, VEGF and hs-CRP plasma levels were measured in 100 patients newly diagnosed with CAD and 33 CAD-free controls. Patients were followed-up for the incidence of major adverse cardiovascular events (MACE) for 8months to 2y. Gene expression of KLK1, CD105 and CD68 was assessed in human coronary endarterectomy specimens. RESULTS: Patients with CAD and acute coronary syndrome (ACS) had significantly elevated KLK1 levels. In addition, the concentration of hs-CRP was increased in ACS patients. A strong positive correlation between plasma KLK1 and the severity of CAD was also demonstrated, suggesting that high KLK1 levels are an independent predictor for CAD. MACE during follow-up significantly correlated with KLK1 levels in the ACS group. Unstable coronary plaques demonstrated markedly increased KLK1 levels, macrophage infiltration and high microvessel density. Additionally, KLK1 staining primarily colocalized with macrophages. CONCLUSIONS: In the present study, plasma KLK1 levels were a useful predictor for the presence and extent of CAD. More extensive studies are, however, necessary in order to validate these findings.

Efficacy of regional renal nerve blockade in patients with chronic refractory heart failure.

BACKGROUND: Increased renal sympathetic nerve activity can result in diuretic resistance in patients with chronic congestive heart failure. We investigated the effect of regional renal nerve blockade on the patients with chronic refractory heart failure and diuretic resistance. METHODS: Eighteen patients with chronic refractory heart failure were enrolled (mean age (64 ± 11) years). The patients were randomly divided into two groups (renal nerve blockade group and standard therapy group, n = 9 each). Renal nerve blockade was performed by percutaneous injection of local anaesthetic under computed tomographic guidance. Heart rate, mean arterial blood pressure, plasma and urine electrolytes, neurohormones, factional excretion of sodium (FENa), 24-hour urine volume were monitored at baseline and the first 24 hours after therapy. Dyspnea and oedema were also evaluated. The major adverse cardiovascular events (MACE), plasma brain natriuretic peptide (BNP) level and left ventricular ejection fraction (LVEF) were compared between the two groups during the 3 - 12 months follow-up period. RESULTS: No complication was observed during the acute phase of renal nerve blockade. After renal nerve blockade, the 24-hour urine volume and FENa were significantly increased, while the level of plasma rennin, angiotensin II, aldosterone, BNP and atrial natriuretic peptide as well as dyspnea and oedema were significantly reduced in renal nerve blockade group compared with baseline and standard therapy group. During three to 12 months of follow-up, the rate of MACE and plasma BNP level were significantly lower, while LVEF was significantly higher in renal nerve blockade group than those in standard therapy group. CONCLUSION: Regional renal nerve blockade may be a safe and effective treatment for patients with chronic refractory heart failure.

Erythropoietin attenuates cardiac dysfunction by increasing myocardial angiogenesis and inhibiting interstitial fibrosis in diabetic rats.

BACKGROUND: Recent studies revealed that erythropoietin (EPO) has tissue-protective effects in the heart by increasing vascular endothelial growth factor (VEGF) expression and attenuating myocardial fibrosis in ischemia models. In this study, we investigated the effect of EPO on ventricular remodeling and blood vessel growth in diabetic rats. METHODS: Male SD rats were randomly divided into 3 groups: control rats, streptozotocin (STZ)-induced diabetic rats, and diabetic rats treated with 1000 U/kg EPO by subcutaneous injection once per week. Twelve weeks later, echocardiography was conducted, and blood samples were collected for counting of peripheral blood endothelial progenitor cells (EPCs). Myocardial tissues were collected, quantitative real-time PCR (RT-PCR) was used to detect the mRNA expression of VEGF and EPO-receptor (EPOR), and Western blotting was used to detect the protein expression of VEGF and EPOR. VEGF, EPOR, transforming growth factor beta (TGF-ß), and CD31 levels in the myocardium were determined by immunohistochemistry. To detect cardiac hypertrophy, immunohistochemistry of collagen type I, collagen type III, and Picrosirius Red staining were performed, and cardiomyocyte cross-sectional area was measured. RESULTS: After 12 weeks STZ injection, blood glucose increased significantly and remained consistently elevated. EPO treatment significantly improved cardiac contractility and reduced diastolic dysfunction. Rats receiving the EPO injection showed a significant increase in circulating EPCs (27.85 ± 3.43%, P < 0.01) compared with diabetic untreated animals. EPO injection significantly increased capillary density as well as EPOR and VEGF expression in left ventricular myocardial tissue from diabetic rats. Moreover, EPO inhibited interstitial collagen deposition and reduced TGF-ß expression. CONCLUSIONS: Treatment with EPO protects cardiac tissue in diabetic animals by increasing VEGF and EPOR expression levels, leading to improved revascularization and the inhibition of cardiac fibrosis.

Fluvastatin attenuates myocardial interstitial fibrosis and cardiac dysfunction in diabetic rats by inhibiting over-expression of connective tissue growth factor.

BACKGROUND: Diabetic myocardiopathy is characterized by myocardial interstitial fibrosis and cardiac dysfunction. Statins were found to exert protective effects on cardiovascular disease by suppressing activation of small G proteins, independently of their lipid-lowering effect. The study investigated the effect of fluvastatin on myocardial interstitial fibrosis, cardiac function and mechanism of its action in diabetic rats. METHODS: Twenty-four male SD rats were randomly assigned to 3 groups: control rats (n = 8), streptozotocin (STZ)-induced diabetic rats (n = 8), and diabetic rats treated with fluvastatin (administered fluvastatin orally, 10 mg/kg body weight per day, n = 8). Twelve weeks later, miniature cardiac catheter was inserted into the left ventricle to conduct hemodynamic examination. Then myocardium tissues were collected, collagen content was detected by picro-sirius red staining, real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of connective tissue growth factor (CTGF), and Western blotting was used to detect the protein expression of CTGF. Rho activity was determined by pull-down assay. RESULTS: After 12 weeks, the left ventricular systolic pressure (LVSP) and maximum rate of left ventricular (LV) pressure rise and fall (+dP/dt max and -dP/dt max) were significantly lower and left ventricular end diastolic pressure (LVEDP) was higher in the diabetic rats than those in the control rats (P < 0.01). Moreover, in LV myocardial tissue of diabetic rats the collagen content, fibronectin, mRNA and protein expression of CTGF and the activity of RhoA were all significantly increased compared with the control rats (P < 0.01). Administration of fluvastain obviously improved the cardiac function of diabetic rats, attenuated fibronectin expression, mRNA and protein expression of CTGF and the activity of RhoA in LV myocardium of diabetic rats. CONCLUSIONS: Fluvastatin attenuates cardiac dysfunction and myocardial interstitial fibrosis of diabetic rat by inhibiting activity of RhoA to down-regulate the overexpression of CTGF, and Rho/Rho-kinase pathway may be an important target in the treatment of diabetic cardiomyopathy.

Prolonged pain to hospital time is associated with increased plasma advanced oxidation protein products and poor prognosis in patients with percutaneous coronary intervention for ST-elevation myocardial infarction.

Plasma advanced oxidation protein products (AOPP) are a biomarker for increased production of reactive oxygen species. We examined the possible association between pain to hospital time, plasma AOPP, and outcome of patients receiving percutaneous coronary intervention (PCI) for ST-elevation acute myocardial infarction (STEMI). Plasma AOPP was determined at hospitalization as well as 24 and 48 h after PCI in 79 patients with suspected STEMI. Patients were stratified into a control group (Group I, n = 21) after exclusion of coronary artery disease, Group II (n = 46) with pain to hospital time <12 h, and Group III (n = 33) with pain to hospital time >12 h. Associations between pain to hospital time and AOPP as well as incidence of major adverse cardiac events (MACE) during 6 months of follow-up were analyzed. Plasma AOPP at admission was significantly higher in patients of Group II (97.58 +/- 23.41 micromol/l) and Group III (184.52 +/- 30.41 micromol/l) in comparison with Group I (57.41 +/- 13.60 micromol/l, all P < 0.001). Plasma AOPP concentration was positively correlated with pain to hospital time and associated with an increased incidence of MACE during the 6-month follow-up period. Prolonged ischemia is associated with increased oxidative stress and poor prognosis in patients treated with PCI for STEMI.

Complement factor H Y402H polymorphism, plasma concentration and risk of coronary artery disease.

BACKGROUND: Inflammation plays an important role in coronary artery disease (CAD). Complement Factor H (CFH) gene has been analyzed in relation to CAD in several studies with conflicting results. The aim of the present study was to investigate the association between the CFH Y402H polymorphism and CAD in Chinese. METHODS AND RESULTS: About 336 patients were enrolled, included 166 patients with CAD and 170 controls. The SNP at CFH Y402H was genotyped by ligase detection reaction and plasma levels of CFH were assayed by enzyme-linked immunosorbent assay. Analysis of genotype frequencies did not reveal any significant difference between CAD patients and controls. There were significant differences in the frequencies of C allele and C allele carriers between early-onset CAD and controls. After adjustment of clinical parameters, significant association was identified for CFH Y402H polymorphism, with C allele carriers having a higher risk of early-onset CAD than carriers of TT genotype (odds ratio [OR] 4.66, 95% CI: 1.23-17.62, P = 0.02). There was no difference of plasma CFH levels between CAD group and controls. CONCLUSIONS: CFH Y402H polymorphism is associated with early-onset CAD in Chinese.