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We introduce an integrative process-based crop model for garlic (

Introduction: The efficacy and specificity of myocardial gene transfer depends on retention of the injectate at the site of gene delivery. However, no direct method exists to confirm myocardial retention of a biologic delivered via an intracardiac transvenous catheter. We tested feasibility of a radiographic contrast media as a gene delivery vehicle, and fluoroscopic assessment of intramyocardial retention as well as proper function of a transgene. Methods and Results: Synthetic mRNA expressing GFP in saline was mixed with an iodine-based radiopaque contrast agent, iopamidol, at 2, 5, 20, 30 and 40%. The minimum content of iopamidol that allowed unequivocal radiographic identification ex vivo was 20%. To validate functional expression of the transgene, GFP mRNA was injected focally into the left ventricular apex of the rat heart upon thoracotomy at 0, 2, 5 or 20% iopamidol solution. On day 5, the hearts were harvested and examined for GFP expression, which illustrated comparable and focal GFP expression in all animals. To test whether gene delivery in a contrast media is compatible with intended disease-modifying activity, we employed TBX18 gene transfer via the right femoral vein in a porcine model of complete heart block. We have previously demonstrated that TBX18 could convert ventricular myocytes to pacemaker cells, and create de novo ventricular pacing in situ. Intracardiac delivery of TBX18 or GFP (n=6 or 2 pigs, respectively) mRNA dissolved in 20% iopamidol to the high His bundle region revealed clear, real-time visualization of the injectate in all pigs. In one of the 8 pigs, the injectate diffused rapidly into the ventricular circulation, which necessitated a repeat injection. The maximum heart rate of TBX18-injected pigs was faster than that of GFP-injected pigs upon β-adrenergic stimulation at 77±12 vs. 43±13 BPM at week 2 ( P =0.08), and at 93±19 vs. 48±3BPM at week 4 ( P Conclusion: Radiographic contrast agent can serve as an effective gene delivery vehicle, allowing real-time and non-invasive assessment of the retention of intramyocardial gene delivery. This approach may be generalizable to other focal gene therapy applications, and minimize suboptimal gene delivery.

Background: We have previously demonstrated that TBX18 suffices to reprogram postnatal ventricular cardiomyocytes to induced pacemaker cells (TBX18-iPMs). However, the nascent automaticity appeared to wane over time, characterized by loss of syncytial pacing but preservation of single cell automaticity. Hypothesis: Based on increase in Tgfβ ligands in TBX18-iPMs and the known role of Tgfβ signaling in electrical remodeling, we hypothesized that loss of syncytial automaticity is due to electrical decoupling of the iPMs mediated by Tgfβ signaling. Methods: Adenoviral vectors expressing either human TBX18 or GFP were used for gene transfer into neonatal rat ventricular myocytes (NRVMs) or adult rat ventricular myocardium in vivo. Results: NRVM monolayers transduced with GFP were mostly quiescent, interspersed by paroxysmal contractions. In contrast, TBX18 transduced NRVM monolayers showed spontaneous and rhythmic contractions, but the syncytial pacing wavered over the next 5-7 days although numerous iPMs continued to beat asynchronously. Treatment of TBX18-iPMs with an inhibitor of Tgfβ receptors, A83-01, preserved syncytial pacing, suggesting that electrical remodeling cues from Tgfβ signaling led to loss of iPM-iPM electrical coupling. We examined the molecules that are integral to the function of gap junction in the myocardium, namely Cx43, N-cadherin and β-catenin. Cx43 and N-cadherin were downregulated in TBX18-iPMs compared to control by 77±16% and 43±11% (p Conclusions: TBX18 activates Tgfβ signaling which suppresses cell-cell electrical coupling. Inhibition of Tgfβ signaling in TBX18-iPMs preserves gap junction components and syncytial pacing.

Resveratrol is a naturally occurring phenol that is generated by plant species following injury or attack by bacterial and fungal pathogens. This compound was first described as the French Paradox in 1992. Later in 2003, resveratrol was reported to activate sirtuins in yeast cells. Recent experimental studies have found that resveratrol offers a variety of benefits that include both anticarcinogenic and anti-inflammatory effects in addition to the ability to reverse obesity, attenuate hyperglycemia and hyperinsulinemia, protect heart and endothelial function, and increase the life span. Multiple molecular targets are associated with the cardioprotective capabilities of resveratrol, and therefore, resveratrol has potential for a wide range of new therapeutic strategies for atherosclerosis, ischemia/reperfusion, metabolic syndrome, cardiac failure, and inflammatory alterations during aging. Expectations for application in human patients, however, suffer from a lack of sufficient clinical evidence in support of these beneficial effects. This article reviews recently reported basic research results that describe the beneficial effects of resveratrol in an attempt to condense the evidence observed in clinical trials and provide support for the future development of novel clinical therapeutics in patients with cardiovascular diseases.

Complete atrioventricular block (CAVB) is a life-threatening arrhythmia. A small animal model of chronic CAVB that properly reflects clinical indices of bradycardia would accelerate the understanding of disease progression and pathophysiology, and the development of therapeutic strategies. We sought to develop a surgical model of CAVB in adult rats, which could recapitulate structural remodeling and arrhythmogenicity expected in chronic CAVB. Upon right thoracotomy, we delivered electrosurgical energy subepicardially via a thin needle into the atrioventricular node (AVN) region of adult rats to create complete AV block. The chronic CAVB animals developed dilated and hypertrophied ventricles with preserved systolic functions due to compensatory hemodynamic remodeling. Ventricular tachyarrhythmias, which are difficult to induce in the healthy rodent heart, could be induced upon programmed electrical stimulation in chronic CAVB rats and worsened when combined with β-adrenergic stimulation. Focal somatic gene transfer of TBX18 to the left ventricular apex in the CAVB rats resulted in ectopic ventricular beats within days, achieving a de novo ventricular rate faster than the slow atrioventricular (AV) junctional escape rhythm observed in control CAVB animals. The model offers new opportunities to test therapeutic approaches to treat chronic and severe CAVB which have previously only been testable in large animal models.