Adenylyl cyclase type 6 (AC6) has favorable effects on the failing heart. However, AC6 has two shortcomings that, if resolved, would provide an optimal therapeutic transgene. First, AC6's large size prevents its expression in adeno-associated virus (AAV) vectors, which would enable longer-term expression. Second, AC6's propensity to increase intracellular levels of cAMP is a potential impediment. Recent data from our laboratory indicate that the beneficial effects of AC6, in large measure, are independent of cAMP generation. The elimination of the amino terminus and the two transmembrane domains (Mi &M2) of AC and subsequent fusing the two cytoplasmic domains (C1 &C2) with an 8 amino acid linker yields a C1C2 protein. C1C2 has an intact catalytic domain, but is disengaged from membrane-associated 6-adrenergic receptors (BAR), and therefore less responsive to BAR stimulation. Our preliminary data indicate that increased expression of C1C2 in cardiac myocytes mimics the beneficial effects of AC6 on Akt activation and ATF3 expression, has favorable effects on cell survival, and improved function of the failing heart. Moreover, C1C2 is sufficiently small to be inserted in an AAV vector with a regulated expression cassette, and will be better suited for targeting to specific microdomains owing to its smaller size. Hypothesis C1C2 expression ? independently B-adrenergic receptor stimulation ? will have beneficial effects on the failing heart. The following 5 Aims will examine the mechanism of action and effects of C1C2 on heart function.
Aim 1 To determine the mechanisms by which C1C2 has beneficial effects on cardiac myocytes Aim2 To determine if cardiac-directed expression of the optimal C1C2 construct will have favorable effects on normal heart function and have minimal deleterious effects even after prolonged high-level cardiac expression Aim 3 To determine if cardiac-directed expression of C1C2 will improve function of the failing heart Aim 4 To determine whether cardiac gene transfer of an AAV vector enabling regulated expression of an optimal C1C2 can safely improve function of the failing mouse heart Aim 5 To determine whether cardiac gene transfer of an AAV vector enabling regulated expression of an optimal C1C2 can safely improve function of the failing pig heart, perform biodistribution and toxicology studies, and file an IND for initiation of a clinical trial

Public Health Relevance

This Project focuses upon the discovery and potential use of new therapeutic genes for the treatment of clinical congestive heart failure so its relevance to the mission of the NHLBI and NIH is clear.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Program Projects (P01)
Project #
2P01HL066941-11A1
Application #
8647149
Study Section
Heart, Lung, and Blood Initial Review Group (HLBP)
Project Start
Project End
Budget Start
2013-09-26
Budget End
2014-06-30
Support Year
11
Fiscal Year
2013
Total Cost
$805,333
Indirect Cost
$222,706
Name
Veterans Medical Research Fdn/San Diego
Department
Type
DUNS #
933863508
City
San Diego
State
CA
Country
United States
Zip Code
92161
Pandey, Amit K; Penny, William F; Bhargava, Valmik et al. (2016) Clinical Evaluation of Heart Failure: Agreement among Tests. PLoS One 11:e0161536
Gao, Mei Hua; Giamouridis, Dimosthenis; Lai, N Chin et al. (2016) One-time injection of AAV8 encoding urocortin 2 provides long-term resolution of insulin resistance. JCI Insight 1:e88322
Schilling, Jan M; Horikawa, Yousuke T; Zemljic-Harpf, Alice E et al. (2016) Electrophysiology and metabolism of caveolin-3-overexpressing mice. Basic Res Cardiol 111:28
Cividini, Federico; Scott, Brian T; Dai, Anzhi et al. (2016) O-GlcNAcylation of 8-Oxoguanine DNA Glycosylase (Ogg1) Impairs Oxidative Mitochondrial DNA Lesion Repair in Diabetic Hearts. J Biol Chem 291:26515-26528
See Hoe, Louise E; Schilling, Jan M; Busija, Anna R et al. (2016) Chronic β1-adrenoceptor blockade impairs ischaemic tolerance and preconditioning in murine myocardium. Eur J Pharmacol 789:1-7
Tran, Chinh; Stary, Creed M; Schilling, Jan M et al. (2015) Role of caveolin-3 in lymphocyte activation. Life Sci 121:35-9
Lai, N Chin; Gao, Mei Hua; Giamouridis, Dimosthenis et al. (2015) Intravenous AAV8 Encoding Urocortin-2 Increases Function of the Failing Heart in Mice. Hum Gene Ther 26:347-56
Schilling, Jan M; Roth, David M; Patel, Hemal H (2015) Caveolins in cardioprotection - translatability and mechanisms. Br J Pharmacol 172:2114-25
Sun, Junhui; Nguyen, Tiffany; Aponte, Angel M et al. (2015) Ischaemic preconditioning preferentially increases protein S-nitrosylation in subsarcolemmal mitochondria. Cardiovasc Res 106:227-36
Markandeya, Yogananda S; Phelan, Laura J; Woon, Marites T et al. (2015) Caveolin-3 Overexpression Attenuates Cardiac Hypertrophy via Inhibition of T-type Ca2+ Current Modulated by Protein Kinase Cα in Cardiomyocytes. J Biol Chem 290:22085-100

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