Abstract 3810: Antiviral RNA Interference Mediated by a Recombinant Cardiotropic AAV9 Vector Improves Cardiac Function in Coxsackievirus B3 Cardiomyopathy

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Wolfgang Poller ◽  
Isaac Sipo ◽  
Dirk Westermann ◽  
Jens Kurreck ◽  
Roland Vetter ◽  
...  
Keyword(s):  
Rna Interference ◽  
Coxsackievirus B3 ◽  
Left Ventricular ◽  
Lv Function ◽  
Target Cells ◽  
Small Interfering Rnas ◽  
Rat Cardiomyocytes ◽  
Terminal Heart Failure ◽  
Novel Therapeutic

RNA interference (RNAi) has potential to be a novel therapeutic strategy in diverse areas of medicine. We report here on targeted RNAi for the treatment of a viral cardiomyopathy which is a major cause of sudden cardiac death or terminal heart failure in children and young adults. RNAi therapy employs small regulatory RNAs to achieve its effect but in vivo use of synthetic small interfering RNAs is limited by instability in plasma and low transfer into target cells. We instead evaluated an RNAi strategy using short hairpin RNA (shRdRp) directed at the RNA polymerase (RdRP) of Coxsackievirus B3 (CoxB3) in HeLa cells, primary rat cardiomyocytes (PNCMs), and CoxB3-infected mice in vivo. A conventional AAV2 vector expressing shRdRp protected HeLa against virus-induced death, but this vector type was unable to transduce PNCMs. In contrast, an analogous pseudotyped AAV2.6 vector was protective also in PNCMs and reduced virus replication by >3 log10 steps. Finally, we evaluated intravenous treatment of mice with an AAV2.9-shRdRp vector since AAV9 carries the most cardiotropic AAV capsid currently known for in vivo use. Mice with CoxB3 cardiomyopathy had disturbed left ventricular (LV) function with impaired parameters of contractility (dP/dtmax 3006±287 vs. 7482±487 mmHg/s, p<0.01) and diastolic relaxation (dP/dtmin -2224±195 vs. -6456±356 mmHg/s, p<0.01 and Tau 16.2±1.1 vs. 10.7±0.6 ms, p<0.01) as compared to control mice. AAV2.9-shRdRp treatment significantly attenuated the cardiac dysfunction compared to control vector-treated mice on day 10 after CoxB3 infection: dP/dtmax 3865±354 vs. 3006±287 mmHg/s (p<0.05) and dP/dtmin -3245±231 vs. −2224±195, mmHg/s (p<0.05), and Tau 11.9±0.5 vs. 16.2±1.1 ms (p<0.01). The data show, for the first time, that intravenously injected AAV9 has the potential to target RNAi to the heart and suggest AAV9-shRNA vectors as a novel therapeutic approach for cardiac disorders.

scholarly journals Non-Viral Delivery and Therapeutic Application of Small Interfering RNAs

Acta Naturae ◽  
2013 ◽  
Vol 5 (3) ◽  
pp. 35-53 ◽  
Author(s):  
N. A. Nikitenko ◽  
V. S. Prassolov
Keyword(s):  
Rna Interference ◽  
Gene Expression Regulation ◽  
Sirna Delivery ◽  
Target Cells ◽  
Powerful Method ◽  
Small Interfering Rnas ◽  
Therapeutic Application ◽  
Rnai Technology ◽  
In Vivo Degradation

RNA interference (RNAi) is a powerful method used for gene expression regulation. The increasing knowledge about the molecular mechanism of this phenomenon creates new avenues for the application of the RNAi technology in the treatment of various human diseases. However, delivery of RNA interference mediators, small interfering RNAs (siRNAs), to target cells is a major hurdle. Effective and safe pharmacological use of siRNAs requires carriers that can deliver siRNA to its target site and the development of methods for protection of these fragile molecules from in vivo degradation. This review summarizes various strategies for siRNA delivery, including chemical modification and non-viral approaches, such as the polymer-based, peptide-based, lipid-based techniques, and inorganic nanosystems. The advantages, disadvantages, and prospects for the therapeutic application of these methods are also examined in this paper.

scholarly journals Delivery Systems for the Direct Application of siRNAs to Induce RNA Interference (RNAi) In Vivo

2006 ◽  
Vol 2006 ◽  
pp. 1-15 ◽  
Author(s):  
Achim Aigner
Keyword(s):  
Rna Interference ◽  
Sirna Delivery ◽  
Critical Factor ◽  
Delivery Systems ◽  
Tumor Xenograft ◽  
Target Cells ◽  
Specific Gene ◽  
Mouse Tumor ◽  
Small Interfering Rnas

RNA interference (RNAi) is a powerful method for specific gene silencing which may also lead to promising novel therapeutic strategies. It is mediated through small interfering RNAs (siRNAs) which sequence-specifically trigger the cleavage and subsequent degradation of their target mRNA. One critical factor is the ability to deliver intact siRNAs into target cells/organs in vivo. This review highlights the mechanism of RNAi and the guidelines for the design of optimal siRNAs. It gives an overview of studies based on the systemic or local application of naked siRNAs or the use of various nonviral siRNA delivery systems. One promising avenue is the the complexation of siRNAs with the polyethylenimine (PEI), which efficiently stabilizes siRNAs and, upon systemic administration, leads to the delivery of the intact siRNAs into different organs. The antitumorigenic effects of PEI/siRNA-mediated in vivo gene-targeting of tumor-relevant proteins like in mouse tumor xenograft models are described.

scholarly journals Computational Investigation of Transmural Differences in Left Ventricular Contractility

2016 ◽  
Vol 138 (11) ◽  
Author(s):  
Hua Wang ◽  
Xiaoyan Zhang ◽  
Shauna M. Dorsey ◽  
Jeremy R. McGarvey ◽  
Kenneth S. Campbell ◽  
...  
Keyword(s):  
Myocardial Contractility ◽  
Ex Vivo ◽  
Experimental Studies ◽  
Contractile Force ◽  
Left Ventricular ◽  
Lv Function ◽  
Fe Model ◽  
Myocardial Layers ◽  
Best Fit

Myocardial contractility of the left ventricle (LV) plays an essential role in maintaining normal pump function. A recent ex vivo experimental study showed that cardiomyocyte force generation varies across the three myocardial layers of the LV wall. However, the in vivo distribution of myocardial contractile force is still unclear. The current study was designed to investigate the in vivo transmural distribution of myocardial contractility using a noninvasive computational approach. For this purpose, four cases with different transmural distributions of maximum isometric tension (Tmax) and/or reference sarcomere length (lR) were tested with animal-specific finite element (FE) models, in combination with magnetic resonance imaging (MRI), pressure catheterization, and numerical optimization. Results of the current study showed that the best fit with in vivo MRI-derived deformation was obtained when Tmax assumed different values in the subendocardium, midmyocardium, and subepicardium with transmurally varying lR. These results are consistent with recent ex vivo experimental studies, which showed that the midmyocardium produces more contractile force than the other transmural layers. The systolic strain calculated from the best-fit FE model was in good agreement with MRI data. Therefore, the proposed noninvasive approach has the capability to predict the transmural distribution of myocardial contractility. Moreover, FE models with a nonuniform distribution of myocardial contractility could provide a better representation of LV function and be used to investigate the effects of transmural changes due to heart disease.

Abstract 276: The Regulatory Effects Of Peroxiredoxin II On Phospholamban Phosphorylation And Cardiac Contractile Function In Vivo

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Wen Zhao ◽  
Xiaojing Shi ◽  
Wenjuan Zhou ◽  
Huimin Wang ◽  
Xuepeng Geng ◽  
...  
Keyword(s):  
Cardiac Contractility ◽  
Left Ventricular ◽  
Active Inhibitor ◽  
Rat Cardiomyocytes ◽  
Cardiac Contractile ◽  
Adenoviral Delivery ◽  
Anti Oxidant ◽  
Contraction And Relaxation ◽  
Phospholamban Phosphorylation

Peroxiredoxin II (prxII), a cytosolic form of the anti-oxidant peroxiredoxin family, was recently found to be decreased in failing human hearts. Interestingly, in hyperdynamic hearts of two genetically modified mouse models with: a) phospholamban ablation; and b) overexpression of the active inhibitor-1 of protein phosphatase 1, the levels of this cellular peroxidase (prxII) were markedly increased. Acute overexpression of prxII by adenoviral-delivery in adult rat cardiomyocytes (Ad-prxII) was associated with decreases in the basal rates of contraction and relaxation, as well as calcium kinetics. Accordingly, Ad-prxII-AS infected cardiomyocytes exhibited enhanced contractile parameters and Ca-kinetics. The depressed or increased contractility by Ad-prxII or Ad-prxII-AS was associated with parallel decreases or increases in phosphorylation of phospholamban (Ser16 and Thr17). To determine the in vivo effects of prxII on cardiac contractility, three transgenic lines (TG) with 2-3 fold cardiac-specific overexpression of prxII were generated and their cardiac morphologic and functional phenotypes were characterized. The TG mice exhibited no alterations in cardiac pathology or morphology up to 4 months of age. However, langendorf perfusions revealed that cardiac contractility, including the rates of contraction and relaxation (±dp/dtmax) as well as the left ventricular end systolic pressure (LVESP), were significantly depressed in TG mice (to 75, 76 and 63%, respectively), compared to WTs (100%). The depressed function was not associated with any alterations in the expression levels of key SR calcium handling proteins: SERCA2, total phospholamban, calsequestrin and ryanodine receptor. However, the levels of the phosphorylated PLN at Ser16 were found to be reduced to 50% in the TG mice, compared to WTs. These findings indicate that prxII, an anti-oxidant protein, may regulate basal cardiac contractile performance in vivo through phospholamban phosphorylation.

An Overview of nano delivery systems for targeting RNA interference-based therapy in ulcerative colitis

2021 ◽  
Vol 27 ◽  
Author(s):  
Iman Alfagih ◽  
Basmah Aldosari ◽  
Bushra AlQuadeib ◽  
Alanood Almurshedi ◽  
Murtaza Tambuwala
Keyword(s):  
Ulcerative Colitis ◽  
Rna Interference ◽  
Protein Expression ◽  
Messenger Rna ◽  
Delivery Systems ◽  
Target Cells ◽  
Intracellular Space ◽  
Therapeutic Benefits ◽  
Negative Effect

: Ulcerative colitis (UC) is one of the main subtypes of inflammatory bowel disease. UC has a negative effect on patients’ quality of life, and it is an important risk factor for the development of colitis-associated cancer. Patients with UC need to take medications for their entire life because no permanent cure is available. Therefore, approaches that target messenger RNA (mRNA) of proinflammatory cytokines or anti-inflammatory cytokines are needed to improve the safety of UC therapy and promote intestinal mucosa recovery. The major challenge facing RNA interference-based therapy is the delivery of RNA molecules to the intracellular space of target cells. Moreover, nonspecific and systemic protein expression inhibition can result in adverse effects and less therapeutic benefits. Thus, it is important to develop an efficient delivery strategy targeting the cytoplasm of target cells to avoid side effects caused by off-target protein expression inhibition. This review focuses on the most recent advances in the targeted nano delivery systems of siRNAs and mRNA that have shown in vivo efficacy.

Abstract 165: The 18 kDa FGF-2 Prevents the Doxorubicin-induced Cardiac Damage and Amp-activated Kinase Activation, in vitro and in vivo

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Navid Koleini ◽  
Jon Jon Santiago ◽  
Barbara E Nickel ◽  
Robert Fandrich ◽  
Davinder S Jassal ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cell Death ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Wild Type ◽  
Rat Cardiomyocytes ◽  
Ventricular Ejection Fraction ◽  
Compound C

Introduction: Protection of the heart from chemotherapeutic (Doxorubicin, DOX) drug-induced toxicity is a desirable goal, to limit side effects of cancer treatments. DOX toxicity has been linked to the activation (phosphorylation) of the AMP-activated kinase, AMPK. The 18 kDa low molecular weight isoform of fibroblast growth factor 2 (Lo-FGF-2) is a known cardioprotective and cytoprotective agent. In this study we have tested the ability of Lo-FGF-2 to protect from DOX-induced damage in rat cardiomyocytes in vitro, and in transgenic mouse models in vivo, in relation to AMPK activation. Methods: Rat neonatal cardiomyocytes in culture were exposed to DOX (0.5 μM) in the presence or absence of pre-treatment Lo-FGF-2 (10 ng/ml). Compound C was used to block phosphorylation (activity) of AMPK. Levels of cell viability/death (using Calcein-AM/Propidium iodide assay), phospho -and total AMPK, and apoptotic markers such as active caspase 3 were analyzed. In addition, transgenic mice expressing only Lo-FGF2, and wild type mice, expressing both high molecular weight (Hi-FGF2) as well as Lo-FGF2 were subjected to DOX injection (20 mg/kg, intraperitoneal); echocardiography was used to examine cardiac function at baseline and at 10 days post-DOX. Results: DOX-induced cell death of cardiomyocytes in culture was maximal at 24 hours post-DOX coinciding with significantly increased in activated (phosphorylated) AMPK. Compound C attenuated DOX-induced cardiomyocyte loss. Pre-incubation with Lo-FGF-2 decreased DOX induced cell death, and also attenuated the phosphorylation of AMPK post-DOX. Relative levels of phospho-AMPK were lower in the hearts of Lo-FGF2-expressing male mice compared to wild type. DOX-induced loss of contractile function (left ventricular ejection fraction and endocardial velocity) was negligible in Lo-FGF2-expressing mice but significant in wild type mice. Conclusion: Lo-FGF-2 protects the heart from DOX-induced damage in vitro and in vivo, by a mechanism likely involving an attenuation of AMPK activity.

Role of myofibrillogenesis regulator-1 in myocardial hypertrophy

2006 ◽  
Vol 290 (1) ◽  
pp. H279-H285 ◽  
Author(s):  
Xiuhua Liu ◽  
Tianbo Li ◽  
Sheng Sun ◽  
Feifei Xu ◽  
Yiguang Wang
Keyword(s):  
Rna Interference ◽  
Cardiac Hypertrophy ◽  
Protein Expression ◽  
Western Blotting ◽  
Left Ventricular ◽  
Neonatal Rat ◽  
Heart Weight ◽  
Homologous Gene ◽  
Ang Ii ◽  
Rat Cardiomyocytes

Myofibrillogenesis regulator-1 (MR-1) is a novel homologous gene, identified from a human skeletal muscle cDNA library, that interacts with contractile proteins and exists in human myocardial myofibrils. The present study investigated MR-1 protein expression in hypertrophied myocardium and MR-1 involvement in cardiac hypertrophy. Cardiac hypertrophy was induced by abdominal aortic stenosis (AAS) in Sprague-Dawley rats. Left ventricular (LV) hypertrophy was assessed by the ratio of LV wet weight to whole heart weight (LV/HW) or LV weight to body weight (LV/BW). Rat MR-1 (rMR-1) expression in the myocardium was detected by immunohistochemical and Western blotting analysis. Hypertrophy was induced by ANG II incubation in cultured neonatal rat cardiomyocytes. The effect of rMR-1 RNA interference on ANG II-induced hypertrophy was studied by transfection of cardiomyocytes with an RNA interference plasmid, pSi-1, which targets rMR-1. Hypertrophy in cardiomyocytes was assessed by [3H]Leu incorporation and myocyte size. rMR-1 protein expression in cardiomyocytes was detected by Western blotting. We found that AAS resulted in a significant increase in LV/HW and LV/BW: 89% and 86%, respectively ( P < 0.01). Immunohistochemistry and Western blot analysis demonstrated upregulated rMR-1 protein expression in hypertrophic myocardium. ANG II induced a 24% increase in [3H]Leu incorporation and a 65.8% increase in cell size compared with control cardiomyocytes ( P < 0.01), which was prevented by treatment with losartan, an angiotensin (AT1) receptor inhibitor, or transfection with pSi-1. rMR-1 expression increased in ANG II-induced hypertrophied cardiomyocytes, and pSi-1 transfection abolished the upregulation. These findings suggest that MR-1 is associated with cardiac hypertrophy in rats in vivo and in vitro.

scholarly journals Acute impact of changes to hemodynamic load on the left ventricular strain-volume relationship in young and older men

2020 ◽  
Vol 318 (4) ◽  
pp. R743-R750 ◽  
Author(s):  
Hugo G. Hulshof ◽  
Arie P. van Dijk ◽  
Maria T. E. Hopman ◽  
Chris F. van der Sluijs ◽  
Keith P. George ◽  
...  
Keyword(s):  
Older Men ◽  
Left Ventricular ◽  
Lv Function ◽  
Diastolic Phase ◽  
Early Diastole ◽  
Volume Relationship ◽  
Acute Increase ◽  
Dimensional Echocardiography ◽  
Two Dimensional Echocardiography

Chronic changes in left ventricular (LV) hemodynamics, such as those induced by increased afterload (i.e., hypertension), mediate changes in LV function. This study examined the proof of concept that 1) the LV longitudinal strain (ε)-volume loop is sensitive to detecting an acute increase in afterload, and 2) these effects differ between healthy young versus older men. Thirty-five healthy male volunteers were recruited, including 19 young (24 ± 2 yr) and 16 older participants (67 ± 5 yr). Tests were performed before, during, and after 10-min recovery from acute manipulation of afterload. Real-time hemodynamic data were obtained and LV longitudinal ε-volume loops were calculated from four-chamber images using two-dimensional echocardiography. Inflation of the anti-gravity (anti-G) suit resulted in an immediate increase in heart rate, blood pressure, and systemic vascular resistance and a decrease in stroke volume (all P < 0.05). This was accompanied by a decrease in LV peak ε, slower slope of the ε-volume relationship during early diastole, and an increase in uncoupling (i.e., compared with systole; little change in ε per volume decline during early diastole and large changes in ε per volume decline during late diastole) (all P < 0.05). All values returned to baseline levels after recovery (all P > 0.05). Manipulation of cardiac hemodynamics caused comparable effects in young versus older men (all P > 0.05). Acute increases in afterload immediately change the diastolic phase of the LV longitudinal ε-volume loop in young and older men. This supports the potency of the LV longitudinal ε-volume loop to provide novel insights into dynamic cardiac function in humans in vivo.

scholarly journals Bottlebrush-architectured poly(ethylene glycol) as an efficient vector for RNA interference in vivo

2019 ◽  
Vol 5 (2) ◽  
pp. eaav9322 ◽  
Author(s):  
Dali Wang ◽  
Jiaqi Lin ◽  
Fei Jia ◽  
Xuyu Tan ◽  
Yuyan Wang ◽  
...  
Keyword(s):  
Rna Interference ◽  
Ethylene Glycol ◽  
Target Genes ◽  
Area Under The Curve ◽  
Fold Increase ◽  
Small Interfering Rnas ◽  
Poly Ethylene Glycol ◽  
Linear Poly ◽  
Poly Ethylene

Nonhepatic delivery of small interfering RNAs (siRNAs) remains a challenge for development of RNA interference–based therapeutics. We report a noncationic vector wherein linear poly(ethylene glycol) (PEG), a polymer generally considered as inert and safe biologically but ineffective as a vector, is transformed into a bottlebrush architecture. This topology provides covalently embedded siRNA with augmented nuclease stability and cellular uptake. Consisting almost entirely of PEG and siRNA, the conjugates exhibit a ~25-fold increase in blood elimination half-life and a ~19-fold increase in the area under the curve compared with unmodified siRNA. The improved pharmacokinetics results in greater tumor uptake and diminished liver capture. Despite the structural simplicity these conjugates efficiently knock down target genes in vivo without apparent toxic and immunogenic reactions. Given the benign biological nature of PEG and its widespread precedence in biopharmaceuticals, we anticipate the brush polymer–based technology to have a significant impact on siRNA therapeutics.

scholarly journals Both aerobic exercise and resveratrol supplementation attenuate doxorubicin-induced cardiac injury in mice

2013 ◽  
Vol 305 (2) ◽  
pp. E243-E253 ◽  
Author(s):  
Vernon W. Dolinsky ◽  
Kyle J. Rogan ◽  
Miranda M. Sung ◽  
Beshay N. Zordoky ◽  
Mark J. Haykowsky ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Aerobic Exercise ◽  
Exercise Performance ◽  
Cardiac Injury ◽  
Left Ventricular ◽  
Aerobic Exercise Training ◽  
Lv Function ◽  
Endoplasmic Reticulum Calcium ◽  
Lv Remodeling

Because doxorubicin (DOX)-containing chemotherapy causes left ventricular (LV) dysfunction and remodeling that can progress to heart failure, strategies to alleviate DOX cardiotoxicity are necessary to improve health outcomes of patients surviving cancer. Although clinical evidence suggests that aerobic exercise training (ET) can prevent cardiotoxicity in patients undergoing DOX chemotherapy, the physiological mechanisms involved have not been extensively studied, nor is it known whether compounds [such as resveratrol (RESV)] have similar beneficial effects. With the use of a murine model of chronic DOX exposure, this study compared the efficacy of modest ET to RESV treatment on exercise performance, LV remodeling, and oxidative stress resistance. Mice were divided into four groups that received saline, DOX (8 mg/kg ip, one time per week), DOX + RESV (4 g/kg diet, ad libitum), and DOX + ET (45 min of treadmill exercise, 5 days/wk) for 8 wk. LV function and morphology were evaluated by in vivo echocardiography. DOX caused adverse LV remodeling that was partially attenuated by modest ET and completely prevented by RESV. These effects were paralleled by improvements in exercise performance. The cardioprotective properties of ET and RESV were associated with reduced levels of atrial natriuretic peptide and the lipid peroxidation by-product, 4-hydroxy-2-nonenal. In addition, ET and RESV increased the expression of cardiac sarcoplasmic/endoplasmic reticulum calcium-ATPase 2a, superoxide dismutase, mitochondrial electron transport chain complexes, and mitofusin-1 and -2 in mice administered DOX. Compared with modest ET, RESV more effectively prevented DOX-induced LV remodeling and was associated with the reduction of DOX-induced oxidative stress. Our findings have important implications for protecting patients against DOX-associated cardiac injury.

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