In certain forms of hypertension and other diseases, vascular density is reduced and angiogenesis is impaired, increasing vascular resistance, reducing tissue perfusion, and limiting the efficacy of pharmacotherapy. Studies from our laboratory and others have implicated a role for the renin-angiotensin system in both the growth and regression of vessel density. Consequently, it is critical to understand the mechanisms by which renin is regulated and the relationship between its regulation and angiogenesis. The studies proposed in Project 3 of this program represent a systematic effort to identify the defect that impacts renin gene expression and is responsible for the abnormal angiogenic response to physiological stimulation in the low renin Dahl salt- sensitive (SS) rat. We hypothesize that a mutation(s) in the SS rat is responsible for the impaired renin gene regulation and abnormal angiogenesis in this model. In three specific aims we will identify sequence variants, demonstrate that these variants impact renin regulation in vitro, and, using a transgenic approach, demonstrate that the SS allele is capable of eliminating normal renin regulation and the angiogenic phenotype in vivo. Beginning with a series of congenic rat strains surrounding the renin gene on chromosome 13 (chr 13), as well as a targeted congenic strain that captures the candidate region distal to renin, we will identify the variants and mechanisms by which they act, controlling renin expression and the angiogenic response. This project will take advantage of our capabilities in high-throughput DNA sequencing, proteomics, and a set of unique animal and cell models, and builds upon discoveries made in the previous funding period that demonstrate: 1) The inbred SS has both hypertension and a defect in the ability to increase plasma renin activity that results in an impaired angiogenic response and 2) a unique region of rat chr 13 located 1 Mb downstream from the proximal renin promoter is responsible for this impairment of renin activity and angiogenesis in the SS. Several aspects of this work make it unique in its approach. We have identified and produced a set of animal models that will provide us with the genomic tools for identifying the mutation that interacts with the renin gene to impair renin production in the SS background. We have the ability to isolate and study primary microvascular endothelial and juxtaglomerular cells from the subcongenic lines in order to define the function ofthe alleles captured in our rat lines. We have unique strengths in proteomic analysis of DNA binding proteins that will help to determine proteins that bind to the proximal renin promoter Finally, the combined strength of our group brings expertise in the physiology of angiogenesis, genomics, in vivo gene manipulation and all of the associated techniques required for successful completion of the proposed studies i.e. from identifying gene(s) to physiological profiling with validation in cell culture and in whole animal model using novel approaches. Project 3 is a critical component to this program because it continues the investigations of the complex regulation and interplay of a set of genes residing in different regions of chr 13 (the chr of interest in all three projects of this program) that collectively contribute to salt-induced hypertension, renal injury, and vascularity/angiogenesis of the microcirculation. This project interacts directly with each of the other projects and is a major user of all of the cores for the development of animal models (Core B), surgical implants (Core C), and administration (Core A). In Project 3, we are focused on vascular density, a critical determinant of vascular resistance and perfusion in hypertension and the role of renin in its regulation.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Program Projects (P01)
Project #
5P01HL082798-08
Application #
8486471
Study Section
Heart, Lung, and Blood Initial Review Group (HLBP)
Project Start
Project End
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
8
Fiscal Year
2013
Total Cost
$486,822
Indirect Cost
$168,638
Name
Medical College of Wisconsin
Department
Type
DUNS #
937639060
City
Milwaukee
State
WI
Country
United States
Zip Code
53226
Dayton, Alex; Exner, Eric C; Bukowy, John D et al. (2016) Breaking the Cycle: Estrous Variation Does Not Require Increased Sample Size in the Study of Female Rats. Hypertension 68:1139-1144
Pavlov, Tengis S; Levchenko, Vladislav; Ilatovskaya, Daria V et al. (2016) Renal sodium transport in renin-deficient Dahl salt-sensitive rats. J Renin Angiotensin Aldosterone Syst 17:
Kotchen, Theodore A; Cowley Jr, Allen W; Liang, Mingyu (2016) Ushering Hypertension Into a New Era of Precision Medicine. JAMA 315:343-4
Cowley Jr, Allen W; Yang, Chun; Kumar, Vikash et al. (2016) Pappa2 is linked to salt-sensitive hypertension in Dahl S rats. Physiol Genomics 48:62-72
Prisco, Anthony R; Hoffmann, Brian R; Kaczorowski, Catherine C et al. (2016) Tumor Necrosis Factor α Regulates Endothelial Progenitor Cell Migration via CADM1 and NF-kB. Stem Cells 34:1922-33
Peterson, Christine B; Stingo, Francesco C; Vannucci, Marina (2016) Joint Bayesian variable and graph selection for regression models with network-structured predictors. Stat Med 35:1017-31
Huang, Baorui; Cheng, Yuan; Usa, Kristie et al. (2016) Renal Tumor Necrosis Factor α Contributes to Hypertension in Dahl Salt-Sensitive Rats. Sci Rep 6:21960
Geurts, Aron M; Mattson, David L; Liu, Pengyuan et al. (2015) Maternal diet during gestation and lactation modifies the severity of salt-induced hypertension and renal injury in Dahl salt-sensitive rats. Hypertension 65:447-55
Salehpour, F; Ghanian, Z; Yang, C et al. (2015) Effects of p67phox on the mitochondrial oxidative state in the kidney of Dahl salt-sensitive rats: optical fluorescence 3-D cryoimaging. Am J Physiol Renal Physiol 309:F377-82
Prisco, Anthony R; Prisco, Michael R; Carlson, Brian E et al. (2015) TNF-α increases endothelial progenitor cell adhesion to the endothelium by increasing bond expression and affinity. Am J Physiol Heart Circ Physiol 308:H1368-81

Showing the most recent 10 out of 80 publications