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Grünblatt E, Bartl J, Iuhos DI, Knezovic A, Trkulja V, Riederer P, Walitza S, Salkovic-Petrisic M. Characterization of cognitive deficits in spontaneously hypertensive rats, accompanied by brain insulin receptor dysfunction. J Mol Psychiatry 2015; 3:6. [PMID: 26110057 PMCID: PMC4479234 DOI: 10.1186/s40303-015-0012-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 05/29/2015] [Indexed: 01/05/2023] Open
Abstract
Background The spontaneously hypertensive rat (SHR) has been used to model changes in the central nervous system associated with cognitive-related disorders. Recent human and animal studies indicate a possible relationship between cognitive deficits, insulin resistance and hypertension. We aimed to investigate whether cognitively impaired SHRs develop central and/or peripheral insulin resistance and how their cognitive performance is influenced by the animal’s sex and age as well as strains used for comparison (Wistar and Wistar-Kyoto/WKY). Methods Three and seven-month-old SHR, Wistar, and WKY rats were studied for their cognitive performance using Morris Water Maze (MWM) and Passive Avoidance tests (PAT). Plasma glucose and insulin were obtained after oral glucose tolerance tests. Cerebral cortex, hippocampus, and striatum status of insulin-receptor (IR) β-subunit and glycogen synthase kinase-3β (GSK3β) and their phosphorylated forms were obtained via ELISA. Results SHRs performed poorly in MWM and PAT in comparison to both control strains but more pronouncedly compared to WKY. Females performed poorer than males and 7-month-old SHRs had poorer MWM performance than 3-month-old ones. Although plasma glucose levels remained unchanged, plasma insulin levels were significantly increased in the glucose tolerance test in 7-month-old SHRs. SHRs demonstrated reduced expression and increased activity of IRβ-subunit in cerebral cortex, hippocampus, and striatum with different regional changes in phospho/total GSK3β ratio, as compared to WKYs. Conclusion Results indicate that cognitive deficits in SHRs are accompanied by both central and peripheral insulin dysfunction, thus allowing for the speculation that SHRs might additionally be considered as a model of insulin resistance-induced type of dementia. Electronic supplementary material The online version of this article (doi:10.1186/s40303-015-0012-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Edna Grünblatt
- University Clinics of Child and Adolescent Psychiatry, University of Zurich, Neumuensterallee 9, 8032 Zurich, Switzerland ; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland ; University Hospital, Clinic and Policlinic for Psychiatry, Psychosomatic and Psychotherapy, University of Würzburg, Füchsleinstr. 15, D-97080 Würzburg, Germany ; University Clinics of Child and Adolescent Psychiatry, University of Zurich, Wagistrasse 12, CH-8952 Schlieren, Switzerland
| | - Jasmin Bartl
- University Clinics of Child and Adolescent Psychiatry, University of Zurich, Neumuensterallee 9, 8032 Zurich, Switzerland
| | - Diana-Iulia Iuhos
- University Hospital, Clinic and Policlinic for Psychiatry, Psychosomatic and Psychotherapy, University of Würzburg, Füchsleinstr. 15, D-97080 Würzburg, Germany
| | - Ana Knezovic
- Department of Pharmacology and Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 11, 10 000 Zagreb, Croatia
| | - Vladimir Trkulja
- Department of Pharmacology and Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 11, 10 000 Zagreb, Croatia
| | - Peter Riederer
- University Hospital, Clinic and Policlinic for Psychiatry, Psychosomatic and Psychotherapy, University of Würzburg, Füchsleinstr. 15, D-97080 Würzburg, Germany
| | - Susanne Walitza
- University Clinics of Child and Adolescent Psychiatry, University of Zurich, Neumuensterallee 9, 8032 Zurich, Switzerland ; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Melita Salkovic-Petrisic
- Department of Pharmacology and Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 11, 10 000 Zagreb, Croatia
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Bakker ENTP, Groma G, Spijkers LJA, de Vos J, van Weert A, van Veen H, Everts V, Arribas SM, VanBavel E. Heterogeneity in arterial remodeling among sublines of spontaneously hypertensive rats. PLoS One 2014; 9:e107998. [PMID: 25251068 PMCID: PMC4175999 DOI: 10.1371/journal.pone.0107998] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 08/21/2014] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVES Spontaneously hypertensive rats (SHR) have been used frequently as a model for human essential hypertension. However, both the SHR and its normotensive control, the Wistar Kyoto rat (WKY), consist of genetically different sublines. We tested the hypothesis that the pathophysiology of vascular remodeling in hypertension differs among rat sublines. METHODS AND RESULTS We studied mesenteric resistance arteries of WKY and SHR from three different sources, at 6 weeks and 5 months of age. Sublines of WKY and SHR showed differences in blood pressure, body weight, vascular remodeling, endothelial function, and vessel ultrastructure. Common features in small mesenteric arteries from SHR were an increase in wall thickness, wall-to-lumen ratio, and internal elastic lamina thickness. CONCLUSIONS Endothelial dysfunction, vascular stiffening, and inward remodeling of small mesenteric arteries are not common features of hypertension, but are subline-dependent. Differences in genetic background associate with different types of vascular remodeling in hypertensive rats.
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Affiliation(s)
- Erik N. T. P. Bakker
- Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands
- * E-mail:
| | - Gergely Groma
- Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands
| | - Léon J. A. Spijkers
- Department of Vascular Medicine and Nephrology, Academic Medical Center, Amsterdam, the Netherlands
| | - Judith de Vos
- Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands
| | - Angela van Weert
- Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands
| | - Henk van Veen
- Van Leeuwenhoek Center for Advanced Microscopy, Department of Cell Biology, Academic Medical Center, Amsterdam, the Netherlands
| | - Vincent Everts
- Van Leeuwenhoek Center for Advanced Microscopy, Department of Cell Biology, Academic Medical Center, Amsterdam, the Netherlands
| | - Silvia M. Arribas
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ed VanBavel
- Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands
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Abramova TO, Redina OE, Smolenskaya SE, Markel AL. Elevated expression of the Ephx2 mRNA in the kidney of hypertensive ISIAH rats. Mol Biol 2013. [DOI: 10.1134/s0026893313060022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zhang-James Y, Middleton FA, Faraone SV. Genetic architecture of Wistar-Kyoto rat and spontaneously hypertensive rat substrains from different sources. Physiol Genomics 2013; 45:528-38. [PMID: 23673728 DOI: 10.1152/physiolgenomics.00002.2013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The spontaneously hypertensive rat (SHR) has been widely used as a model for studies of hypertension and attention deficit/hyperactivity disorder. The inbred Wistar-Kyoto (WKY) rat, derived from the same ancestral outbred Wistar rat as the SHR, are normotensive and have been used as the closest genetic control for the SHR, although the WKY has also been used as a model for depression. Notably, however, substantial behavioral and genetic differences among the WKY substrains, usually from the different vendors and breeders, have been observed. These differences have often been overlooked in prior studies, leading to inconsistent and even contradictory findings. The complicated breeding history of the SHR and WKY rats and the lack of a comprehensive understanding of the genetic background of different commercial substrains make the selection of control rats a daunting task, even for researchers who are mindful of their genetic heterogeneity. In this study, we examined the genetic relationship of 16 commonly used WKY and SHR rat substrains using genome-wide SNP genotyping data. Our results confirmed a large genetic divergence and complex relationships among the SHR and WKY substrains. This understanding, although incomplete without the genome sequence, provides useful guidance in selecting substrains and helps to interpret previous reports when the source of the animals was known. Moreover, we found two closely related, yet distinct WKY substrains that may provide novel opportunities in modeling psychiatric disorders.
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Affiliation(s)
- Yanli Zhang-James
- Department of Psychiatry, State University of New York Upstate Medical University, Syracuse, New York, USA
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Ritz MF, Grond-Ginsbach C, Engelter S, Lyrer P. Gene expression suggests spontaneously hypertensive rats may have altered metabolism and reduced hypoxic tolerance. Curr Neurovasc Res 2012; 9:10-9. [PMID: 22272763 PMCID: PMC3296125 DOI: 10.2174/156720212799297074] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 12/07/2011] [Accepted: 12/15/2011] [Indexed: 12/27/2022]
Abstract
Cerebral small vessel disease (SVD) is an important cause of stroke, cognitive decline and vascular dementia (VaD). It is associated with diffuse white matter abnormalities and small deep cerebral ischemic infarcts. The molecular mechanisms involved in the development and progression of SVD are unclear. As hypertension is a major risk factor for developing SVD, Spontaneously Hypertensive Rats (SHR) are considered an appropriate experimental model for SVD. Prior work suggested an imbalance between the number of blood microvessels and astrocytes at the level of the neurovascular unit in 2-month-old SHR, leading to neuronal hypoxia in the brain of 9-month-old animals. To identify genes and pathways involved in the development of SVD, we compared the gene expression profile in the cortex of 2 and 9-month-old of SHR with age-matched normotensive Wistar Kyoto (WKY) rats using microarray-based technology. The results revealed significant differences in expression of genes involved in energy and lipid metabolisms, mitochondrial functions, oxidative stress and ischemic responses between both groups. These results strongly suggest that SHR suffer from chronic hypoxia, and therefore are unable to tolerate ischemia-like conditions, and are more vulnerable to high-energy needs than WKY. This molecular analysis gives new insights about pathways accounting for the development of SVD.
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Affiliation(s)
- Marie-Françoise Ritz
- Department of Biomedicine, Brain Tumor Biology Laboratory, Pharmazentrum, Klingelbergstrasse 50, 4056 Basel, Switzerland.
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Nabika T, Ohara H, Kato N, Isomura M. The stroke-prone spontaneously hypertensive rat: still a useful model for post-GWAS genetic studies? Hypertens Res 2012; 35:477-84. [PMID: 22399095 DOI: 10.1038/hr.2012.30] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The stroke-prone spontaneously hypertensive rat (SHRSP) is a unique genetic model of severe hypertension and cerebral stroke. SHRSP, as well as the spontaneously hypertensive rat, the parental strain of SHRSP, has made a tremendous contribution to cardiovascular research. However, the genetic mechanisms underlying hypertension and stroke in these rats have not yet been clarified. Recent studies using whole-genome sequencing and comprehensive gene expression analyses combined with classical quantitative trait loci analyses provided several candidate genes, such as Ephx2, Gstm1 and Slc34a1, which still need further evidence to define their pathological roles. Currently, genome-wide association studies can directly identify candidate genes for hypertension in the human genome. Thus, genetic studies in SHRSP and other rat models must be focused on the pathogenetic roles of 'networks of interacting genes' in hypertension, instead of searching for individual candidate genes.
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Affiliation(s)
- Toru Nabika
- Department of Functional Pathology, Shimane University School of Medicine, Izumo, Japan.
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Akira K, Mitome H, Imachi M, Shida Y, Miyaoka H, Hashimoto T. LC-NMR identification of a novel taurine-related metabolite observed in 1H NMR-based metabonomics of genetically hypertensive rats. J Pharm Biomed Anal 2010; 51:1091-6. [DOI: 10.1016/j.jpba.2009.11.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 11/01/2009] [Accepted: 11/07/2009] [Indexed: 11/30/2022]
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Renal glutathione S-transferase μ type 1 expression is already reduced in new-born spontaneously hypertensive rats. J Hypertens 2010; 28:633-4; author reply 634. [DOI: 10.1097/hjh.0b013e328335fa99] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gong W, Klöpfel M, Reutzel-Selke A, Jurisch A, Vogt K, Haase S, Höflich C, Polenz D, Gerstmayer B, Tomiuk S, Volk HD, Pascher A, Sawitzki B. High weight differences between donor and recipient affect early kidney graft function--a role for enhanced IL-6 signaling. Am J Transplant 2009; 9:1742-51. [PMID: 19563340 DOI: 10.1111/j.1600-6143.2009.02725.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The frequency of delayed function of kidney transplants varies greatly and is associated with quality of graft, donor age and the duration of cold ischemia time. Furthermore, body weight differences between donor and recipient can affect primary graft function, but the underlying mechanism is poorly understood. We transplanted kidney grafts from commensurate body weight (L-WD) or reduced body weight (H-WD) donor rats into syngeneic or allogeneic recipients. Twenty-four hours posttransplantation, serum creatinine levels in H-WD recipients were significantly higher compared to L-WD recipients indicating impaired primary graft function. This was accompanied by upregulation of IL-6 transcription and increased tubular destruction in grafts from H-WD recipients. Using DNA microarray analysis, we detected decreased expression of genes associated with kidney function and an upregulation of other genes such as Cyp3a13, FosL and Trib3. A single application of IL-6 into L-WD recipients is sufficient to impair primary graft function and cause tubular damage, whereas immediate neutralization of IL-6 receptor signaling in H-WD recipients rescued primary graft function with well-preserved kidney graft architecture and a normalized gene expression profile. These findings have strong clinical implication as anti-IL6R treatment of patients receiving grafts from lower-weight donors could be used to improve primary graft function.
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Affiliation(s)
- W Gong
- Institute of Medical Immunology, Charité University Medicine, Campus Mitte, Berlin, Germany
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Dmitrieva RI, Hinojos CA, Grove ML, Bell RJ, Boerwinkle E, Fornage M, Doris PA. Genome-wide identification of allelic expression in hypertensive rats. ACTA ACUST UNITED AC 2009; 2:106-15. [PMID: 20031574 DOI: 10.1161/circgenetics.108.809509] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Identification of genes involved in complex cardiovascular disease traits has proven challenging. Inbred animal models can facilitate genetic studies of disease traits. The spontaneously hypertensive rat (SHR) is an inbred model of hypertension that exists in several closely related but genetically distinct lines. METHODS AND RESULTS We used renal gene-expression profiling across 3 distinct SHR lines to identify genes that show different expression in SHR than in the genetically related normotensive control strain, Wistar-Kyoto. To ensure robust discovery of genes showing SHR-specific expression differences, we considered only those genes in which differential expression is replicated in multiple animals of each of multiple hypertensive rat lines at multiple time points during the ontogeny of hypertension. Mutation analysis was performed on the identified genes to uncover allelic variation. We identified those genes in which all SHR lines share a single allele of the gene when normotensive controls (Wistar-Kyoto) have fixed the alternative allele. We then identified which of the differentially expressed genes show expression that is controlled by the alleleic variation present in and around the gene. Allelic expression was demonstrated by observing the effect on gene expression of alleles inherited in the freely segregating F(2) progeny of a cross between SHR and Wistar-Kyoto animals. CONCLUSIONS The result of these studies is the identification of several genes (Ptprj, Ela1, Dapk-2, and Gstt2) in which each of 4 SHR lines examined have fixed the same allele and in which each of 2 Wistar-Kyoto lines have a contrasting allele for which the inherited allele influences the level of gene expression. We further show that alleles of these genes lie in extensive haplotype blocks that have been inherited identical by descent in the hypertensive lines.
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Affiliation(s)
- Renata I Dmitrieva
- Institute of Molecular Medicine and Human Genetics Center, University of Texas Health Science Center, 2121 Holcombe Blvd., Houston, TX 77030, USA
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Wesseling S, Koeners MP, Kantouh F, Joles JA, Braam B. Consequences of perinatal treatment with L-arginine and antioxidants for the renal transcriptome in spontaneously hypertensive rats. Pflugers Arch 2009; 458:513-24. [PMID: 19189121 PMCID: PMC2691531 DOI: 10.1007/s00424-009-0639-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Revised: 01/05/2009] [Accepted: 01/13/2009] [Indexed: 12/23/2022]
Abstract
Treating spontaneously hypertensive rats (SHR) with L-arginine, taurine, and vitamins C and E (ATCE) during nephrogenesis (2 weeks before to 4 weeks after birth) persistently lowers blood pressure. Hypothetically, differential gene expression in kidney of SHR vs. normotensive Wistar-Kyoto rats (WKY) is partially corrected by maternal ATCE in SHR. Differential gene expression in 2-days, 2-weeks, and 48-week-old rats was studied using oligonucleotide chips. Transcription factor binding sites (TFBS) of differentially expressed genes were analyzed in silico. Differential gene expression varied between SHR+ATCE and SHR, suggesting both direct and indirect effects; but, few genes were modulated toward WKY level and there was little overlap between ages. TFBS analysis suggests less Elk-1-driven gene transcription in both WKY and SHR+ATCE vs. SHR at 2 days and 2 weeks. Concluding, in SHR, persistent antihypertensive effects of maternal ATCE are not primarily due to persistent corrective transcription. Less Elk-1-driven transcription at 2 days and 2 weeks may be involved.
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Affiliation(s)
- Sebastiaan Wesseling
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
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Iigaya K, Kumagai H, Nabika T, Harada Y, Onimaru H, Oshima N, Takimoto C, Kamayachi T, Saruta T, Itoh H. Relation of blood pressure quantitative trait locus on rat chromosome 1 to hyperactivity of rostral ventrolateral medulla. Hypertension 2008; 53:42-8. [PMID: 19047583 DOI: 10.1161/hypertensionaha.108.117804] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Genetic factors that induce essential hypertension have been examined using genome-wide linkage analyses. A quantitative trait locus (QTL) region that is closely linked to hypertension has been found on chromosome 1 in stroke-prone spontaneously hypertensive rats (SHRSPs). We used 2 congenic rats in which the blood pressure QTL on rat chromosome 1 was introgressed from SHRSP/Izm to Wistar-Kyoto (WKY)/Izm (WKYpch1.0) and from WKY/Izm to SHRSP/Izm (SHRSPwch1.0) rats by repeated backcrossing. Previous studies reported that the intermediate phenotype of this QTL for hypertension is characterized by the hyperactivity of the sympathetic nervous system in response to physiological and psychological stress. We performed intracellular patch-clamp recordings of rostral ventrolateral medulla (RVLM) neurons from WKY, WKYpch1.0, SHRSPwch1.0, and SHRSPs and compared the basal electrophysiological activities of RVLM neurons and the responses of these neurons to angiotensin II. The basal membrane potential of RVLM neurons from WKYpch1.0 was significantly "shallower" than that of the neurons from WKY. The depolarization of RVLM neurons from WKYpch1.0 in response to angiotensin II was significantly larger than that in neurons from WKY rats, whereas the depolarization of RVLM neurons from SHRSPwch1.0 was significantly smaller than that in neurons from SHRSPs. The response to angiotensin II of RVLM neurons from WKYpch1.0 and SHRSPs was sustained even after the blockade of all of the synaptic transmissions using tetrodotoxin. The QTL on rat chromosome 1 was primarily related to the postsynaptic response of RVLM bulbospinal neurons to brain angiotensin II, whereas both the QTL and other genomic regions influenced the basal activity of RVLM neurons.
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Affiliation(s)
- Kamon Iigaya
- Division of Endocrinology, Metabolism, and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Tokyo.
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Dmitrieva RI, Hinojos CA, Boerwinkle E, Braun MC, Fornage M, Doris PA. Hepatocyte nuclear factor 1 and hypertensive nephropathy. Hypertension 2008; 51:1583-9. [PMID: 18443232 DOI: 10.1161/hypertensionaha.108.110163] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Hypertension in spontaneously hypertensive rat (SHR) is associated with renal redox stress, and we hypothesized that nephropathy arises in SHR-A3 from altered capacity to mitigate redox stress compared with nephropathy-resistant SHR lines. We measured renal expression of redox genes in distinct lines of the spontaneously hypertensive rat (SHR-A3, SHR-B2, SHR-C) and the normotensive Wistar-Kyoto (WKY) strain. The SHR lines differ in either resisting (SHR-B2, SHR-C) or experiencing hypertensive nephropathy (SHR-A3). Immediately before the emergence of hypertensive renal injury expression of redox genes in SHR-A3 was profoundly altered compared with the injury-resistant SHR lines and WKY. This change appeared to arise in antioxidant genes where 16 of 28 were expressed at 34.3% of the level in the reference strain (WKY). No such change was observed in the injury-resistant SHR lines. We analyzed occurrence of transcription factor matrices in the promoters of the downregulated antioxidant genes. In these genes, the hepatocyte nuclear factor 1 (HNF1) transcription factor matrix was found to be nearly twice as likely to be present and the overall frequency of HNF1 sites was nearly 5 times higher, compared with HNF1 transcription factor matrices in antioxidant genes that were not downregulated. We identified 35 other (nonredox) renal genes regulated by HNF1. These were also significantly downregulated in SHR-A3, but not in SHR-B2 or SHR-C. Finally, expression of genes that comprise HNF1 (Tcf1, Tcf2, and Dcoh) was also downregulated in SHR-A3. The present experiments uncover a major change in transcriptional control by HNF1 that affects redox and other genes and precedes emergence of hypertensive renal injury.
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Affiliation(s)
- Renata I Dmitrieva
- Institute of Molecular Medicine, University of Texas HSC at Houston, TX 77030, USA
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Akira K, Masu S, Imachi M, Mitome H, Hashimoto M, Hashimoto T. 1H NMR-based metabonomic analysis of urine from young spontaneously hypertensive rats. J Pharm Biomed Anal 2007; 46:550-6. [PMID: 18164575 DOI: 10.1016/j.jpba.2007.11.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 11/11/2007] [Accepted: 11/16/2007] [Indexed: 12/21/2022]
Abstract
Spontaneously hypertensive rats (SHR) and their substrains are a useful model for studying essential hypertension which is a complex, polygenic, and multifactorial disorder. Their genetic and metabolic features are of great interest because they may provide insights into the mechanism of blood pressure regulation. We have compared urinary metabolic profiles of young SHR with those of their age-matched normotensive controls, Wistar Kyoto rats, using (1)H NMR-based metabonomics. Principal components analysis was applied to the NMR spectral data after data-reduced and normalized by the total integral or the creatinine integral. Consequently, a clear separation of urine samples between the two strains was observed in the principal components scores plot. The loadings plot from the data normalized by the creatinine integral showed that many metabolites such as citrate, alpha-ketoglutarate, and hippurate contributed to the separation, and the urinary levels of most metabolites used in this study, including these three, were lower in SHR than in Wistar Kyoto rats. These metabolic changes may be concerned with blood pressure regulation in SHR, although a relation to other strain differences cannot be ruled out. The present study suggests the usefulness of a (1)H NMR-based metabonomic approach using SHR in the field of hypertension research.
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Affiliation(s)
- Kazuki Akira
- College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
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Clemitson JR, Dixon RJ, Haines S, Bingham AJ, Patel BR, Hall L, Lo M, Sassard J, Charchar FJ, Samani NJ. Genetic dissection of a blood pressure quantitative trait locus on rat chromosome 1 and gene expression analysis identifies SPON1 as a novel candidate hypertension gene. Circ Res 2007; 100:992-9. [PMID: 17332427 PMCID: PMC3533402 DOI: 10.1161/01.res.0000261961.41889.9c] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A region with a major effect on blood pressure (BP) is located on rat chromosome 1. We have previously isolated this region in reciprocal congenic strains (WKY.SHR-Sa and SHR.WKY-Sa) derived from a cross of the spontaneously hypertensive rat (SHR) with the Wistar-Kyoto rat (WKY) and shown that there are 2 distinct BP quantitative trait loci, BP1 and BP2, in this region. Sisa1, a congenic substrain from the SHR.WKY-Sa animals carrying an introgressed segment of 4.3Mb, contains BP1. Here, we report further dissection of BP1 by the creation of 2 new mutually exclusive congenic substrains (Sisa1a and Sisa1b) and interrogation of candidate genes by expression profiling and targeted transcript sequencing. Only 1 of the substrains (Sisa1a) continued to demonstrate a BP difference but with a reduced introgressed segment of 3Mb. Exonic sequencing of the 20 genes located in the Sisa1a region did not identify any major differences between SHR and WKY. However, microarray expression profiling of whole kidney samples and subsequent quantitative RT-PCR identified a single gene, Spon1 that exhibited significant differential expression between the WKY and SHR genotypes at both 6 and 24 weeks of age. Western blot analysis confirmed an increased level of the Spon1 gene product in SHR kidneys. Spon1 belongs to a family of genes with antiangiogenic properties. These findings justify further investigation of this novel positional candidate gene in BP control in hypertensive rat models and humans.
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Affiliation(s)
- Jenny-Rebecca Clemitson
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Richard J. Dixon
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Steve Haines
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Andrew J. Bingham
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Bhakti R. Patel
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Laurence Hall
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Ming Lo
- Departement de Physiologie et Pharmacologie Clinique, Faculte de Pharmacie, 69373 Lyon cedex 08, France
| | - Jean Sassard
- Departement de Physiologie et Pharmacologie Clinique, Faculte de Pharmacie, 69373 Lyon cedex 08, France
| | - Fadi J. Charchar
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
| | - Nilesh J. Samani
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, United Kingdom
- Corresponding author. Professor N J. Samani, Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, LE3 9QP, U.K. Tel No. +44 116 2563021, Fax No. +44 116 2875792, E-mail:
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Saad Y, Garrett MR, Manickavasagam E, Yerga-Woolwine S, Farms P, Radecki T, Joe B. Fine-mapping and comprehensive transcript analysis reveals nonsynonymous variants within a novel 1.17 Mb blood pressure QTL region on rat chromosome 10. Genomics 2007; 89:343-53. [PMID: 17218081 PMCID: PMC1808207 DOI: 10.1016/j.ygeno.2006.12.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 11/23/2006] [Accepted: 12/09/2006] [Indexed: 10/23/2022]
Abstract
The presence of blood pressure (BP) quantitative trait loci (QTL) on rat chromosome 10 has been clearly demonstrated by linkage analysis and substitution mapping. Using congenic strains containing the LEW rat chromosomal segments on the Dahl salt-sensitive (S) rat background, further iterations of congenic substrains were constructed and characterized to fine-map a chromosome 10 region (QTL1) linked to blood pressure. Comparison of seven congenic substrains refined QTL1 to a 1.17 Mb segment flanked by D10Mco88 and D10Mco89, which are located at 71,513,116 and 72,684,774 bp, respectively. The newly defined QTL1, containing 18 genes, is captured in its entirety within a single congenic substrain. A thorough transcript analysis revealed that 3 of these 18 genes, Ccl5, Ddx52, and RGD1559577, had nonsynonymous allelic variations between the S rat and the LEW rat. None of the detected transcripts within the newly defined QTL1 are implicated directly in BP control in humans or model organisms. Therefore, the present work defines a novel blood pressure QTL with three potential quantitative trait nucleotides.
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Affiliation(s)
- Yasser Saad
- Department of Physiology, Pharmacology, Metabolism, and Cardiovascular Sciences, University of Toledo, Health Science Campus, 3035 Arlington Avenue, Toledo, OH 43614-5804, USA
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Joe B, Letwin NE, Garrett MR, Dhindaw S, Frank B, Sultana R, Verratti K, Rapp JP, Lee NH. Transcriptional profiling with a blood pressure QTL interval-specific oligonucleotide array. Physiol Genomics 2005; 23:318-26. [PMID: 16204469 DOI: 10.1152/physiolgenomics.00164.2004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Although the evidence for a genetic predisposition to human essential hypertension is compelling, the genetic control of blood pressure (BP) is poorly understood. The Dahl salt-sensitive (S) rat is a model for studying the genetic component of BP. Using this model, we previously reported the identification of 16 different genomic regions that contain one or more BP quantitative trait loci (QTLs). The proximal region of rat chromosome 1 contains multiple BP QTLs. Of these, we have localized the BP QTL1b region to a 13.5-cM (20.92 Mb) region. Interestingly, five additional independent studies in rats and four independent studies in humans have reported genetic linkage for BP control by regions homologous to QTL1b. To view the overall renal transcriptional topography of the positional candidate genes for this QTL, we sought a comparative gene expression profiling between a congenic strain containing QTL1b and control S rats by employing 1) a saturated QTL1b interval-specific oligonucleotide array and 2) a whole genome cDNA microarray representing 20,465 unique genes that are positioned outside the QTL. Results indicated that 17 of the 231 positional candidate genes for this QTL are differentially expressed between the two strains tested. Surprisingly, >1,500 genes outside of QTL1b were differentially expressed between the two rat strains. Integrating the results from the two approaches revealed at least one complex network of transcriptional control initiated by the positional candidate Nr2f2. This network appears to account for the majority of gene expression differences occurring outside of the QTL interval. Further substitution mapping is currently underway to test the validity of each of these differentially expressed positional candidate genes. These results demonstrate the importance of using a saturated oligonucleotide array for identifying and prioritizing differentially expressed positional candidate genes of a BP QTL.
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Affiliation(s)
- Bina Joe
- Department of Physiology and Cardiovascular Genomics, Medical University of Ohio, Toledo, Ohio 43614-5804, USA.
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