Jian-qiang Hu

Plasma ghrelin and obestatin levels are increased in spontaneously hypertensive rats.

Obestatin, encoded by the same gene as ghrelin, was first described as a physiological opponent of ghrelin. We investigated fasting plasma ghrelin and obestatin levels in spontaneously hypertensive rats and Wistar-Kyoto rats. We found that ghrelin levels, obestatin levels and the ratio of ghrelin to obestatin were significantly higher in spontaneously hypertensive rats than Wistar-Kyoto rats. Systolic blood pressure and diastolic blood pressure were positively correlated; however, heart period and baroreflex sensitivity were negatively correlated with ghrelin levels. Systolic blood pressure was positively correlated, whereas baroreflex sensitivity was negatively correlated with obestatin levels. In addition, systolic blood pressure was a significantly independent variable of ghrelin levels, obestatin levels, and the ghrelin to obestatin ratio in a multiple regression analysis. Our data suggests that there is a disturbance of ghrelin and obestatin in the circulation of spontaneously hypertensive rats and the ghrelin/obestatin system might play a role in blood pressure regulation.

Identification and functional analysis of a novel PRKAG2 mutation responsible for Chinese PRKAG2 cardiac syndrome reveal an important role of non-CBS domains in regulating the AMPK pathway

BACKGROUND PRKAG2 gene encodes the γ2 regulatory subunit of AMP-activated protein kinase (AMPK) that acts as a sensor of cellular energy status, and its germline mutations are responsible for PRKAG2 cardiac syndrome (PCS). The majority of missense mutations of cystathionine beta-synthase (CBS) domains found in PCS impair the binding activity of PRKAG2 to adenosine derivatives, and therefore lead to PRKAG2 function impairment and AMPK activity alteration, resulting in a familial syndrome of ventricular preexcitation, conduction defects, and cardiac hypertrophy. However, it is unclear about the PRKAG2 mutation in the non-CBS domain. Here, a Chinese family exhibiting the cardiac syndrome associated with a novel heterozygous PRKAG2 mutation (Gly100Ser) mapped to exon 3 encoding a non-CBS domain is described and the function of this novel mutation was investigated in vitro. METHODS The PRKAG2 G100S and R302Q mutations were constructed by a two-step polymerase chain reaction and then transfected into CCL13 cells by lentivirus vectors. Wild-type PRKAG2 gene transfection was used as a negative control. PRKAG2 expression was determined by Western blot. Immunofluorescence was used to localize the intracellular PRKAG2 proteins. MTT assay was performed to explore the effect of mutations on cell proliferation. Periodic acid-Schiff staining was used for detecting glycogen accumulation. AMPK concentration was measured with enzyme-linked immunosorbent assay. RESULTS Our results showed neither intracellular localization of PRKAG2 nor cell growth was altered. In contrast, PRKAG2 protein expression levels were significantly reduced by this mutation. Furthermore, PRKAG2-mediated activity of AMPK was attenuated, resulting in glycogen metabolism dysregulation. These findings revealed that non-CBS domains of PRKAG2 were essential to the regulation of AMPK activity, similar to CBS. CONCLUSIONS Our study ascribes a crucial regulatory role to the novel PRKAG2 G100S mutation, and reiterates that PCS occurs as a consequence of AMPK signaling abnormality caused by PRKAG2 gene mutations.

Animal Experimental Study of the Fully Biodegradable Atrial Septal Defect (ASD) Occluder

This study was conducted to evaluate the feasibility, safety, biocompatibility, and degradation features of a fully biodegradable occluder for closure of atrial septal defect (ASD) in an acute canine model. The ASD was created in 20 healthy mongrel dogs by the brockenbrough needle, and the fully biodegradable occluders were implanted by self-made delivery system. The success rate and complications were observed. Acute ASD models were successfully created in 18 dogs, and 16 occluders were successfully implanted in the ASD models. Animals were sacrificed at different times after procedure. The cardiac gross anatomy showed that all occluders were stable in the interatrial septum, no vegetation or thrombus formation was observed on the surface of all occluders. They were embedded into endogenous host tissue gradually at 12-week follow-up. Different periods of pathological observations suggested that the occluders degraded gradually over about 24 weeks and essentially became an integral part of the septum. Transcatheter closure of ASD in acute canine model using the fully biodegradable ASD occluder has the potential of a high successful rate of technique, excellent biocompatibility, and fewer complications with adequate, immediate, and short-term results.

Intracoronary infusion of bone marrow-derived mononuclear cells contributes to longstanding improvements of left ventricular performance and remodelling after acute myocardial infarction: A meta-analysis

BACKGROUND Conflicting results exist now on the sustained effects of intracoronary bone marrow-derived mononuclear cells (BMMNCs) infusion in patients with acute myocardial infarction (AMI). METHODS Systematical literature search of PubMed, ISI Web of Science, and Cochrane databases was conducted. We included the randomised controlled trials with at least 12-month follow-up data for AMI patients receiving primary percutaneous coronary intervention in addition to intracoronary BMMNCs transfer or not (the control). Summary statistics were calculated using random-effects models. RESULTS A total of 10 trials with 757 patients were available for analysis. The pooled statistics showed intracoronary administration of BMMNCs significantly improved post-infarction left ventricular ejection fraction (weight mean differences [WMD]=4.04%, 95% confidence intervals [CI], 3.01-5.07%; p<0.01), and attenuated the enlargement of left ventricular end-diastolic volume (WMD=-6.13 ml, 95%CI, -10.56 ml to -1.69 ml; p=0.007) as well as infarct size (WMD=-2.47%, 95%CI, -3.79% to -1.15%; p=0.0002). However, for the major adverse clinical events (MACEs), there appeared to be neutral results (between-group differences of p>0.10). CONCLUSIONS Intracoronary BMMNCs infusion leads to longstanding and moderate improvements of post-infarction left ventricular performance as well as remodelling. Meanwhile, the procedure did not increase the risk of MACEs.

A new pan-nitinol occluder for transcatheter closure of ventricular septal defects in a canine model.

BACKGROUND The Amplatzer ventricular septal defect (VSD) occluder has a fixed stainless steel pin bottom protruding out of the surface at the center of the discs on both sides. Theoretically, this protruding bottom may interfere with epithelialization or, in some cases, cause thrombosis. OBJECTIVE To evaluate a new type of pan-nitinol VSD occluder without the protruding stainless steel pin bottom on both sides in a canine VSD model designed to ensure safety, effectiveness, and feasibility. METHODS AND RESULTS VSDs were successfully created by transseptal ventricular septal puncture with a Brockenbrough needle and dilation with an 8-mm-diameter balloon via the right jugular vein in 9 out of 12 canines. The new type VSD occluder was successfully implanted in 8 of the 9 modeled canines. No procedure- or device-related complication was observed. Transthoracic echocardiography and MRI 2 months after device implantations showed that there was no device dislocation or heart valve dysfunction in 6 of the 8 tested canines. In addition, gross and pathological examinations 3-6 months after implantation showed no corrosion of the devices or serious inflammatory reactions in the modeled animals. Complete endothelialization was seen over the surface of the discs. CONCLUSIONS The new pan-nitinol VSD device can be successfully implanted in a canine VSD model via a transcatheter approach featuring high success rate, low risk of procedure-related complications, and sound biocompatibility. The result suggests that this new VSD occluder could be used safely in future clinical trials for further test.

Development and preclinical evaluation of a biodegradable ventricular septal defect occluder.

This study evaluated the feasibility, effectiveness, and safety of a biodegradable (BD) occluder for closure of ventricular septal defect (VSD) in an acute canine model.

Symptomatic Sinus Tachycardia with Perpetuating Slow Pathway: Successful Treatment with Radiofrequency Ablation

We report a case of sinus tachycardia with perpetuating slow pathway (SP) conduction in a 42‐year‐old woman who developed severe symptoms as a result of atrioventricular (AV) desynchronization. The restoration of an AV synchrony, achieved with selective radiofrequency ablation of the SP, eliminated the symptomatic arrhythmia and may represent a reasonable therapeutic option despite the fact that the patient has no AV‐node reentrant tachycardia. This case demonstrates the importance of AV timing.