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Limited reports exist regarding adeno-associated virus (AAV) biodistribution in swine. This study assessed biodistribution following antegrade intracoronary and intravenous delivery of two self-complementary serotype 9 AAV (AAV9sc) biologics designed to target signaling in the cardiomyocyte considered important for the development of heart failure. Under the control of a cardiomyocyte-specific promoter, AAV9sc.shmAKAP and AAV9sc.RBD express a small hairpin RNA for the perinuclear scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) and an anchoring disruptor peptide for p90 ribosomal S6 kinase type 3 (RSK3), respectively. Quantitative PCR was used to assess viral genome (vg) delivery and transcript expression in Ossabaw and Yorkshire swine tissues. Myocardial viral delivery was 2–5 × 105 vg/µg genomic DNA (gDNA) for both infusion techniques at a dose ∼1013 vg/kg body wt, demonstrating delivery of ∼1–3 viral particles per cardiac diploid genome. Myocardial RNA levels for each expressed transgene were generally proportional to dose and genomic delivery, and comparable with levels for moderately expressed endogenous genes. Despite significant AAV9sc delivery to other tissues, including the liver, neither biologic induced toxic effects as assessed using functional, structural, and circulating cardiac and systemic markers. These results indicate successful targeted delivery of cardiomyocyte-selective viral vectors in swine without negative side effects, an important step in establishing efficacy in a preclinical experimental setting.

Heart failure (HF) patients with deteriorating right ventricular (RV) structure and function have a nearly twofold increased risk of death compared with those without. Despite the well-established clinical risk, few studies have examined the molecular signature associated with this HF condition. The purpose of this study was to integrate morphological, molecular, and functional data with the transcriptome data set in the RV of a preclinical model of cardiometabolic HF. Ossabaw swine were fed either normal diet without surgery (lean control, n = 5) or Western diet and aortic-banding (WD-AB; n = 4). Postmortem RV weight was increased and positively correlated with lung weight in the WD-AB group compared with CON. Total RNA-seq was performed and gene expression profiles were compared and analyzed using principal component analysis, weighted gene co-expression network analysis, module enrichment analysis, and ingenuity pathway analysis. Gene networks specifically associated with RV hypertrophic remodeling identified a hub gene in MAPK8 (or JNK1) that was associated with the selective induction of the extracellular matrix (ECM) component fibronectin. JNK1 and fibronectin protein were increased in the right coronary artery (RCA) of WD-AB animals and associated with a decrease in matrix metalloproteinase 14 protein, which specifically degrades fibronectin. RCA fibronectin content was correlated with increased vascular stiffness evident as a decreased elastin elastic modulus in WD-AB animals. In conclusion, this study establishes a molecular and transcriptome signature in the RV using Ossabaw swine with cardiometabolic HF. This signature was associated with altered ECM regulation and increased vascular stiffness in the RCA, with selective dysregulation of fibronectin.

RNA secondary structure is important for designing therapeutics, understanding protein-RNA binding and predicting tertiary structure of RNA. Several databases and downloadable programs exist that specialize in the three-dimensional (3D) structure of RNA, but none focus specifically on secondary structural motifs such as internal, bulge and hairpin loops. The RNA Characterization of Secondary Structure Motifs (RNA CoSSMos) database is a freely accessible and searchable online database and website of 3D characteristics of secondary structure motifs. To create the RNA CoSSMos database, 2156 Protein Data Bank (PDB) files were searched for internal, bulge and hairpin loops, and each loop's structural information, including sugar pucker, glycosidic linkage, hydrogen bonding patterns and stacking interactions, was included in the database. False positives were defined, identified and reclassified or omitted from the database to ensure the most accurate results possible. Users can search via general PDB information, experimental parameters, sequence and specific motif and by specific structural parameters in the subquery page after the initial search. Returned results for each search can be viewed individually or a complete set can be downloaded into a spreadsheet to allow for easy comparison. The RNA CoSSMos database is automatically updated weekly and is available at http://cossmos.slu.edu.