Abstract 39: Adrenal ßArrestin1 Raises Serum Aldosterone Levels And Blood Pressure, Both Significant Stroke Risk Factors, In Experimental Rats And Mice

Introduction: It is widely accepted nowadays that elevation of serum levels of aldosterone, a mineralocorticoid hormone with toxic effects in several cardiovascular tissues, including the heart and cerebral blood vessels, can significantly raise stroke risk. The success of mineralocorticoid receptor blockers, such as eplerenone, at preventing stroke attacks attests to this. Aldosterone is normally produced and secreted by the adrenal cortex in response to angiotensin II. We recently reported that adrenal βarrestin1 (βarr1) plays a crucial role in the physiological angiotensin II-stimulated aldosterone production in the adrenal cortex, leading to marked elevation of circulating serum aldosterone levels in vivo (Lymperopoulos A. et al., Proc. Natl. Acad. Sci. USA. 2009;106:5825-5830). Hypothesis: Herein, we examined the potential impact of this adrenal βarr1-dependent aldosterone elevation on stroke risk in experimental animals in vivo. Methods: We used the βarr1 knockout (βarr1KO) mouse model, studying it alongside wild type (WT) control mice, and also adult male Sprague-Dawley rats, in which adrenal βarr1 was overexpressed in vivo via adrenal-targeted adenoviral-mediated βarr1 gene transfer. Serum aldosterone was measured by ELISA and blood pressure via telemetry. Results: Serum aldosterone at 7 days post-in vivo gene delivery was markedly elevated in adrenal βarr1-overexpressing rats (536+50 pg/ml), compared to control rats receiving the green fluorescent protein (GFP) adenoviral transgene (235+40 pg/ml, p<0.05, n=5). This translated to a significant increase in mean arterial pressure of the βarr1-overexpressing rats (155+5 mmHg) compared to control GFP-expressing rats (137+8 mmHg, p<0.05, n=5), again at 7 days post-in vivo gene delivery, which was prevented by concurrent eplerenone treatment. In contrast, βarr1KO mice had significantly lower serum aldosterone levels (270+20 pg/ml) compared to WT controls (498+35 pg/ml, p<0.05, n=5), at 4 weeks post-experimental myocardial infarction. Conclusions: Adrenal βarr1 up-regulation can dramatically increase circulating aldosterone levels and systemic blood pressure, thus conferring increased risk for stroke in experimental rodents.

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Semliki Forest virus vectors: efficient vehicles for in vitro and in vivo gene delivery

FEBS Letters ◽

10.1016/s0014-5793(01)02707-7 ◽

2001 ◽

Vol 504 (3) ◽

pp. 99-103 ◽

Cited By ~ 43

Author(s):

Kenneth Lundstrom ◽

Christophe Schweitzer ◽

Daniel Rotmann ◽

Danielle Hermann ◽

Edith M. Schneider ◽

...

Keyword(s):

Gene Delivery ◽

Semliki Forest Virus ◽

Virus Vectors ◽

In Vivo Gene Delivery

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In vivo gene delivery by embryonic-stem-cell–derived astrocytes for malignant gliomas

Neuro-Oncology ◽

10.1215/15228517-2008-056 ◽

2009 ◽

Vol 11 (2) ◽

pp. 102-108 ◽

Cited By ~ 18

Author(s):

Mahmud Uzzaman ◽

Gordon Keller ◽

Isabelle M. Germano

Keyword(s):

Stem Cell ◽

Gene Delivery ◽

Embryonic Stem Cell ◽

Malignant Gliomas ◽

Embryonic Stem ◽

In Vivo Gene Delivery

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Abstract MP03: ROCK2 Specific Inhibition Attenuates Angiotensin II-induced Hypertension In Mice

Hypertension ◽

10.1161/hyp.78.suppl_1.mp03 ◽

2021 ◽

Vol 78 (Suppl_1) ◽

Author(s):

Daniel J Fehrenbach ◽

Meena S Madhur

Keyword(s):

Blood Pressure ◽

T Cell ◽

Angiotensin Ii ◽

Repeated Measures ◽

Flow Cytometric Analysis ◽

Coiled Coil ◽

Ang Ii ◽

Induced Hypertension

Hypertension, or an elevated blood pressure, is the primary modifiable risk factor for cardiovascular disease, the number one cause of mortality worldwide. We previously demonstrated that Th17 activation and interleukin 17A (IL-17A)/IL-21 production is integral for the full development of a hypertensive phenotype as well as the renal and vascular damage associated with hypertension. Rho-associated coiled-coil containing protein Kinase 2 (ROCK2) serves as a molecular switch upregulating Th17 and inhibiting regulatory T cell (Treg) differentiation. We hypothesize that hypertension is characterized by excessive T cell ROCK2 activation leading to increased Th17/Treg ratios and ultimately end-organ damage. We first showed in vitro that KD025, an experimental orally bioavailable ROCK2 inhibitor inhibits Th17 cell proliferation and IL-17A/IL-21 production. To determine if hypertensive stimuli such as endothelial stretch increases T cell ROCK2 expression, we cultured human aortic endothelial cells exposed to 5% (normotensive) or 10% (hypertensive) stretch with circulating human T cells and HLA-DR+ antigen presenting cells. Hypertensive stretch increased T cell ROCK2 expression 2-fold. We then tested the effect of ROCK2 inhibition with KD025 (50mg/kg i.p. daily) in vivo on angiotensin II (Ang II)-induced hypertension. Treatment with KD025 significantly attenuated the hypertensive response within 1 week of Ang II treatment (systolic blood pressure: 139± 8 vs 108±7mmHg) and this persisted for the duration of the 4 week study reaching blood pressures 20 mmHg lower (135±13mmHg) than vehicle treated mice (158±4mmHg p<0.05 effect of treatment 2-way Repeated Measures ANOVA). Flow cytometric analysis of tissue infiltrating leukocytes revealed that KD025 treatment increased Treg/Th17 ratios in the kidney (0.61±0.03 vs 0.79±0.08, p<0.05 student’s t-test). Thus, T cell ROCK2 may be a novel therapeutic target for the treatment of hypertension.

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Polyelectrolyte Complexes of Low Molecular Weight PEI and Citric Acid as Efficient and Nontoxic Vectors for in Vitro and in Vivo Gene Delivery

Bioconjugate Chemistry ◽

10.1021/acs.bioconjchem.5b00576 ◽

2016 ◽

Vol 27 (3) ◽

pp. 549-561 ◽

Cited By ~ 27

Author(s):

M. Dolores Giron-Gonzalez ◽

Rafael Salto-Gonzalez ◽

F. Javier Lopez-Jaramillo ◽

Alfonso Salinas-Castillo ◽

Ana Belen Jodar-Reyes ◽

...

Keyword(s):

Molecular Weight ◽

Citric Acid ◽

Gene Delivery ◽

Low Molecular Weight ◽

Polyelectrolyte Complexes ◽

In Vivo Gene Delivery

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In Vivo Gene Delivery into hCD34+ Cells in a Humanized Mouse Model

Methods in Molecular Biology - Viral Vectors for Gene Therapy ◽

10.1007/978-1-61779-095-9_15 ◽

2011 ◽

pp. 367-390 ◽

Cited By ~ 12

Author(s):

Cecilia Frecha ◽

Floriane Fusil ◽

François-Loïc Cosset ◽

Els Verhoeyen

Keyword(s):

Gene Delivery ◽

Mouse Model ◽

Humanized Mouse ◽

Humanized Mouse Model ◽

In Vivo Gene Delivery

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Abstract T MP99: What Are the Blood Pressure Levels Associated With the Lowest Stroke Rates in the Elderly? Findings From the Reasons for Geographic and Racial Differences in Stroke (regards) Cohort Study

Stroke ◽

10.1161/str.45.suppl_1.tmp99 ◽

2014 ◽

Vol 45 (suppl_1) ◽

Author(s):

Maciej Banach ◽

Samantha Bromfield ◽

George Howard ◽

Virginia J Howard ◽

Alberto Zanchetti ◽

...

Keyword(s):

Blood Pressure ◽

Incidence Rate ◽

Racial Differences ◽

Stroke Risk ◽

Reference Group ◽

Elderly Persons ◽

Stroke Incidence ◽

Increased Risk ◽

Adjusted Incidence Rate ◽

Adjusted Incidence

OBJECTIVES: To identify the blood pressure (BP) level associated with the lowest stroke incidence in elderly persons taking antihypertensive medication in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. METHODS: We categorized 13,948 REGARDS participants with hypertension into 3 age groups: 55-64, 65-74 and ≥75 years old and 5 levels of treated systolic BP (SBP): <120 (reference group), 120-129, 130-139, 140-149, and ≥150 mmHg, and 4 levels of diastolic BP (DBP) levels: <70 (reference group), 70-79, 80-89, and ≥90 mmHg. Participants without a history of stroke were followed for a median of 5.7 years (maximum 8.5 years) for incident stroke (n=425). RESULTS: For participants at age 55-64 SBP level <120 mmHg and DBP <70 mmHg were associated with the lowest risk of stroke (incidence per 1,000 person-years: 2.4, 95%Cl: 1.4-4.0 and 2.5, 95%Cl: 1.3-4.7, respectively). Higher stroke risk was observed at SBP ≥140 mmHg. For those aged 65-74, stroke incidence was increased at SBP ≥130 mmHg and at lower DBP levels (with the lowest stroke risk for DBP ≥90 mmHg). For participants ≥75 years SBP ≥150 mmHg was associated with the highest risk of stroke (incidence rate: 15.0, 95%Cl: 10.5-21.3) but no increased risk was observed for SBP between 120-149 mmHg. For DBP, stroke incidence was highest for DBP <70 mmHg (adjusted incidence rate: 9.8; 95%Cl: 6.8-14.1), and lowest for DBP ≥90 mmHg (adjusted incidence rate: 6.5; 95%Cl: 2.9-14.5) (see table). CONCLUSIONS: These results suggest that the lowest risk for stroke for the participants between 55-64 years old are at BP levels <140/70 mmHg, for persons 65-74 we should aim at SBP levels <130 mmHg, and for the oldest patients at SBP <150 with DBP ≥90 mmHg for both groups. For participants aged ≥65 a caution should be kept with the reduction of DBP <90 mmHg, what requires further investigations. Key words: blood pressure, elderly, hypertension, treatment, mortality, stroke.

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Kallistatin Inhibits Endothelial Cell Proliferation, Migration and Adhesion in Vitro and Angiogenesis in the Ischemic Hindlimb of Rats

Hypertension ◽

10.1161/hyp.36.suppl_1.706-e ◽

2000 ◽

Vol 36 (suppl_1) ◽

pp. 706-707

Author(s):

Robert Q Miao ◽

Jun Agata ◽

Lee Chao ◽

Julie Chao

Keyword(s):

Cell Proliferation ◽

Endothelial Cell ◽

Gene Delivery ◽

Fluorescent Protein ◽

Regional Blood Flow ◽

Endothelial Cell Proliferation ◽

Hek 293

P76 Kallistatin is a serine proteinase inhibitor (serpin) which has multifunctions including regulation of tissue kallikrein activity, blood pressure, inflammation and neointima hyperplasia. In this study, we investigated the potential role of kallistatin in vascular biology by studying its effects on the proliferation, migration and adhesion of cultured primary human endothelial cells in vitro, and angiogenesis in the ischemic hindlimb of rats. Purified kallistatin significantly inhibits cultured endothelial cell proliferation, migration and adhesion induced by VEGF or bFGF. To further investigate the role of kallistatin in vascular growth in vivo, we prepared adenovirus carrying the human kallistatin gene under the control of the cytomegalovirus promoter/enhancer (Ad.CMV-cHKBP). Expression of recombinant human kallistatin in HEK 293 cells transfected with Ad.CMV-cHKBP was identified by a specific ELISA. The effect of adenovirus-mediated kallistatin gene delivery on angiogenesis was evaluated in a rat model of hindlimb ischemia. Adenovirus carrying the human kallistatin or green fluorescent protein (GFP) gene were injected locally into the ischemic adductor at the time of surgery. Histological and morphometric analysis at 14 days post injection showed that adenovirus-mediated kallistatin gene delivery significantly reduced capillary density in the ischemic muscle as compared to that of control rats injected with GFP. The anti-angiogenic effect of kallistatin was associated with reduced regional blood flow in the ischemic hindlimb measured by microsphere assays. Expression of human kallistatin was identified in the injected muscle and immunoreactive human kallistatin levels were measured in the muscle and in the circulation of rats following kallistatin gene delivery. These results demonstrate a novel role of kallistatin in the inhibition of angiogenesis and in vascular remodeling.

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