[Overexpression of sarcoplasmic reticulum calcium ATPase induced hemodynamic and proteomic changes in a dog model of heart failure].

OBJECTIVE: Overexpression of SERCA2a could improve cardiac function in human and experimental heart failure (HF) models. We observed the proteomics changes post SERCA2a overexpression in a pacing induced HF model in dogs. METHODS: Beagles were divided into four groups: control group, HF group (230 beats/min for 4 weeks), HF + EGFP group (myocardial injection of 1 x 10(12) v.g recombinant adeno-associated virus carrying enhanced green fluorescent protein gene, rAAV2/1-EGFP) and HF + SERCA2a group (myocardial injection of 1 x 10(12) v.g recombinant adeno-associated virus carrying SERCA2a gene, rAAV2/1-SERCA2a). Thirty days after gene transduction, left ventricular systolic and diastolic functions were measured by echocardiography and invasive hemodynamics in all animals. By use of 2-dimensional gel electrophoresis (2-DE), -500 distinct protein spots were detected in myocardium of all animals. Protein spots observed to be altered between failing and SERCA2a overexpressed hearts were subjected to tryptic peptide mass fingerprinting for identification by MALDI-TOF mass spectrometry in combination with LC/MS/MS analysis. RESULTS: At 30 day after gene transfer, HF signs were significantly reduced, cardiac function [LVSP: (214.72 +/- 31.74) mm Hg (1 mm Hg = 0.133 kPa) vs. (139.32 +/- 36.79) mm Hg, +dp/dt(max): (6779.43 +/- 217.58) mm Hg/s vs. (2746.85 +/- 931.23) mm Hg/s and -dp/dt(max): (-4341.42 +/- 322.02) mm Hg/s vs. (-2531.14 +/- 616.15) mm Hg/s, LVEDP: (21.86 +/- 6.95) mm Hg vs. (59.78 +/- 6.92) mm Hg] significantly improved in HF + SERCA2a dogs than those in HF + EGFP group(all P < 0.05) and parameters were comparable between HF + SERCA2a and control groups. We identified alterations in the expression level of more than 10 proteins in myocardium. These protein changes were observed mainly in two subcellular compartments: the cardiac contractile apparatus and metabolism/energetics. CONCLUSION: These results showed that overexpression of SERCA2a could improve cardiac function accompanied with numerous alterations in protein expressions involved in calcium handling, myofibrils, and energy production in this dog model of chronic heart failure.

Central venous catheter-related thrombosis in senile male patients: New risk factors and predictors.

Central venous catheterization (CVC)-related venous thrombosis is a common but serious clinical complication, thus prevention and treatment on this problem should be extensively investigated. In this research, we aimed to investigate the incidence rate of CVC-related venous thrombosis in senile patients and give a further discussion on the related risk factors and predictors. A total of 324 hospitalized senile male patients subjected to CVC were selected. Retrospective investigation and analysis were conducted on age, underlying diseases, clinical medications, catheterization position and side, catheter retention time, and incidence of CVC-related venous thrombosis complications. Basic laboratory test results during catheterization and thrombogenesis were also collected and analyzed. Among the 324 patients, 20 cases (6.17%) of CVC-related venous thrombosis were diagnoseds. The incidence rate of CVC-related venous thrombosis in subclavian vein catheterization was significantly lower than that in femoral vein catheterization (P<0.01) and that in internal jugular vein catheterization (P<0.05). No statistically significant difference was found between femoral vein catheterization and internal jugular vein catheterization (P<0.05). Previous venous thrombosis history (P<0.01), high lactate dehydrogenase level (P<0.01), low high-density lipoprotein (HDL) level (P<0.05), and low albumin level (P<0.05) were found as risk factors or predictors of CVC-related venous thrombosis in senile male patients. Subclavian vein catheterization was the most appropriate choice among senile patients to decrease the incidence of CVC-related venous thrombosis. Previous venous thrombosis history, high lactate dehydrogenase level, low HDL level, and low albumin level were important risk factors in predicting CVC-related venous thrombosis.

Toe photoplethysmographic monitor, a promising noninvasive technique for tracking systolic blood pressure trends beat-to-beat.

The call for early detection of hypotension creates a heavy demand for new methods that can monitor trends in blood pressure (BP) levels continuously and noninvasively. Photoplethysmography (PPG) is widely used in hemodynamic analysis. We assessed the feasibility of toe PPG in tracing BP trends using BP readings obtained by standard intermittent noninvasive BP measurements from the arm of a patient with severe hypoxic-ischemic brain injury. We demonstrated that an attenuated or inversed dicrotic wave of toe PPG is predictive of BP trends, and this method could be applicable for the continuous noninvasive monitoring of systolic BP at a beat-by-beat basis.

Polymorphisms of angiotensin-converting enzyme 2 gene confer a risk to lone atrial fibrillation in Chinese male patients.

BACKGROUND: Growing epidemiologic evidence has indicated that genetics can predispose individuals to the occurrence of lone atrial fibrillation (AF). The angiotensin-converting enzyme 2 (ACE2) gene has been established to be associated with hypertension and left ventricular hypertrophy. The objective of our study was to investigate the association of ACE2 gene polymorphisms with lone AF. METHODS: A total of 265 consecutive lone AF patients and 289 healthy controls were successfully investigated. The polymorphisms rs2106809 and rs2285666 were genotyped by polymerase chain reaction (PCR) and direct sequencing. A Logistic regression model was used to determine the odds ratio (OR) and 95% confidence intervals (CI) of variations of ACE2 for lone AF. RESULTS: The T allele of rs2106809 conferred an increased risk for lone AF (OR 1.24, 95% CI 1.01-1.52, P = 0.03) in males after adjustment for conventional risk factors. SNP at rs2285666 in males was not significantly different between AF patients and controls. No association was found between the two polymorphisms in the female population with lone AF. After (36.3 ± 4.5) months of follow-up, the end point data were obtained: death (cardiac and noncardiac), ischemic stroke, and heart failure. In the male subgroup, the associations between rs2106809 T male carriers and combined end points including ischemic stroke, heart failure, and death in our study were of significance (OR 3.6, 95% CI 1.0-13.1, P = 0.04). CONCLUSIONS: The results indicate that polymorphism at ACE2 gene is associated with male lone AF in a Chinese Han population. Lone AF males who carry the rs2106809 T allele are associated with adverse cardiac events.

Ameliorated stress related proteins are associated with improved cardiac function by sarcoplasmic reticulum calcium ATPase gene transfer in heart failure.

BACKGROUND: Previous studies showed that overexpression of sarco-endoplasmic reticulum calcium ATPase (SERCA2a) in a variety of heart failure (HF) models was associated with greatly enhanced cardiac performance. However, it still undefined the effect of SERCA2a overexpression on the systemic inflammatory response and neuro-hormonal factors. METHODS: A rapid right ventricular pacing model of experimental HF was used in beagles. Then the animals underwent recombinant adeno-associated virus 1 (rAAV1) mediated gene transfection by direct intra-myocardium injection. HF animals were randomized to receive the SERCA2a gene, enhanced green fluorescent protein (control) gene, or equivalent phosphate buffered saline. Thirty days after gene delivery, the cardiac function was evaluated by echocardiographic testing. The protein level of SERCA2a was measured by western blotting. The proteomic analysis of left ventricular (LV) sample was determined using two-dimensional (2-D) gel electrophoresis and MALDI-TOF-MS. The serum levels of the systemic inflammatory and neuro-hormonal factors were assayed using radioimmunoassay kits. RESULTS: The cardiac function improved after SERCA- 2a gene transfer due to the significantly increased SERCA2a protein level. Beagles treated with SERCA2a had significantly decreased serum levels of the inflammatory markers (interleukin-6 and tumor necrosis factor-α) and neuro-hormonal factors (brain natriuretic peptide, endothelin-1 and angiotensin II) compared with HF animals. The myocardial proteomic analysis showed that haptoglobin heavy chain, heat shock protein (alpha-crystallin-related, B6) were down-regulated, and galectin-1 was up-regulated in SERCA2a group compared with HF group, companied by up-regulated contractile proteins and NADH dehydrogenase. CONCLUSIONS: These findings demonstrate that regional intramyocardial injections of rAAV1-SERCA2a vectors may improve global LV function, correlating with reverse activation of the systemic inflammatory, excessive neuroendocrine factors and the stress-associated myocardial proteins, suggesting that the beneficial effects of SERCA2a gene transfer may involve the attenuation of stress-associated reaction.

Improvement in cardiac function after sarcoplasmic reticulum Ca2+-ATPase gene transfer in a beagle heart failure model.

BACKGROUND: Heart failure (HF) is a major cause of morbidity and mortality worldwide, but current treatment modalities cannot reverse the underlying pathological state of the heart. Gene-based therapies are emerging as promising therapeutic modalities in HF patients. Our previous studies have shown that recombinant adeno-associated viral (rAAV) gene transfer of Sarco-endoplasmic reticulum calcium ATPase (SERCA2a) can be effective in treating rats with chronic heart failure (CHF). The aim of this study was to examine the effects of SERCA2a gene transfer in a large HF animal model. METHODS: HF was induced in beagles by rapid right ventricular pacing (230 beats/min) for 30 days. A reduced rate ventricular pacing (180 beats/min) was continued for another 30 days. The beagles were assigned to four groups: (a) control group (n = 4); (b) HF group (n = 4); (c) enhanced green fluorescent protein group (n = 4); and (d) SERCA2a group (n = 4). rAAV1-EGFP (1 x 10(12) microg) and rAAV1-SERCA2a (1 x 10(12) microg) were delivered intramyocardially. SERCA2a expression was assessed by Western blotting and immunohistochemistry. RESULTS: Following 30 days of SERCA2a gene transfer in HF beagles its protein expression was significantly higher than in the HF group than in the control group (P < 0.05). Heart function improved along with the increase in SERCA2a expression. Left ventricular systolic function significantly improved, including the ejection fraction, left ventricular systolic pressure, maximal rate of rise of left ventricular pressure (+dp/dt(max)), and the maximal rate of decline of left ventricular pressure (-dp/dt(max)) (P < 0.05). Left ventricular end-diastole pressure significantly decreased (P < 0.05). The expression of SERCA2a in the myocardial tissue was higher in the SERCA2a group than in the HF group (P < 0.05). CONCLUSIONS: Intramyocardial injection of rAAV1-SERCA2a can improve the cardiac function in beagles induced with HF. We expect further studies on SERCA2a's long-term safety, efficacy, dosage and the optimization before using it in humans with HF.