Neural programming of mesenteric and renal arteries

There is evidence for developmental origins of vascular dysfunction yet little understanding of maturation of vascular smooth muscle (VSM) of regional circulations. We measured maturational changes in expression of myosin phosphatase (MP) and the broader VSM gene program in relation to mesenteric small resistance artery (SRA) function. We then tested the role of the sympathetic nervous system (SNS) in programming of SRAs and used genetically engineered mice to define the role of MP isoforms in the functional maturation of the mesenteric circulation. Maturation of rat mesenteric SRAs as measured by qPCR and immunoblotting begins after the second postnatal week and is not complete until maturity. It is characterized by induction of markers of VSM differentiation (smMHC, γ-, α-actin), CPI-17, an inhibitory subunit of MP and a key target of α-adrenergic vasoconstriction, α1-adrenergic, purinergic X1, and neuropeptide Y1 receptors of sympathetic signaling. Functional correlates include maturational increases in α-adrenergic-mediated force and calcium sensitization of force production (MP inhibition) measured in first-order mesenteric arteries ex vivo. The MP regulatory subunit Mypt1 E24+/LZ- isoform is specifically upregulated in SRAs during maturation. Conditional deletion of mouse Mypt1 E24 demonstrates that splicing of E24 causes the maturational reduction in sensitivity to cGMP-mediated vasorelaxation (MP activation). Neonatal chemical sympathectomy (6-hydroxydopamine) suppresses maturation of SRAs with minimal effect on a conduit artery. Mechanical denervation of the mature rat renal artery causes a reversion to the immature gene program. We conclude that the SNS captures control of the mesenteric circulation by programming maturation of the SRA smooth muscle.

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Tenascin-C in Heart Diseases—The Role of Inflammation

International Journal of Molecular Sciences ◽

10.3390/ijms22115828 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5828

Author(s):

Kyoko Imanaka-Yoshida

Keyword(s):

Ventricular Remodeling ◽

Heart Diseases ◽

Genetically Engineered ◽

Matricellular Protein ◽

Myocardial Repair ◽

Inflammatory Reactions ◽

Tenascin C ◽

Genetically Engineered Mice

Tenascin-C (TNC) is a large extracellular matrix (ECM) glycoprotein and an original member of the matricellular protein family. TNC is transiently expressed in the heart during embryonic development, but is rarely detected in normal adults; however, its expression is strongly up-regulated with inflammation. Although neither TNC-knockout nor -overexpressing mice show a distinct phenotype, disease models using genetically engineered mice combined with in vitro experiments have revealed multiple significant roles for TNC in responses to injury and myocardial repair, particularly in the regulation of inflammation. In most cases, TNC appears to deteriorate adverse ventricular remodeling by aggravating inflammation/fibrosis. Furthermore, accumulating clinical evidence has shown that high TNC levels predict adverse ventricular remodeling and a poor prognosis in patients with various heart diseases. Since the importance of inflammation has attracted attention in the pathophysiology of heart diseases, this review will focus on the roles of TNC in various types of inflammatory reactions, such as myocardial infarction, hypertensive fibrosis, myocarditis caused by viral infection or autoimmunity, and dilated cardiomyopathy. The utility of TNC as a biomarker for the stratification of myocardial disease conditions and the selection of appropriate therapies will also be discussed from a clinical viewpoint.

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miR-146a is a significant brake on autoimmunity, myeloproliferation, and cancer in mice

Journal of Experimental Medicine ◽

10.1084/jem.20101823 ◽

2011 ◽

Vol 208 (6) ◽

pp. 1189-1201 ◽

Cited By ~ 528

Author(s):

Mark P. Boldin ◽

Konstantin D. Taganov ◽

Dinesh S. Rao ◽

Lili Yang ◽

Jimmy L. Zhao ◽

...

Keyword(s):

Molecular Mechanisms ◽

Immune Cell ◽

Myeloid Cell ◽

Genetically Engineered ◽

Biological Processes ◽

Targeted Deletion ◽

Genetically Engineered Mice ◽

Immune Defects ◽

Molecular Brake

Excessive or inappropriate activation of the immune system can be deleterious to the organism, warranting multiple molecular mechanisms to control and properly terminate immune responses. MicroRNAs (miRNAs), ∼22-nt-long noncoding RNAs, have recently emerged as key posttranscriptional regulators, controlling diverse biological processes, including responses to non-self. In this study, we examine the biological role of miR-146a using genetically engineered mice and show that targeted deletion of this gene, whose expression is strongly up-regulated after immune cell maturation and/or activation, results in several immune defects. Collectively, our findings suggest that miR-146a plays a key role as a molecular brake on inflammation, myeloid cell proliferation, and oncogenic transformation.

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Elucidating the role of Agl in bladder carcinogenesis by generation and characterization of genetically engineered mice

Carcinogenesis ◽

10.1093/carcin/bgy139 ◽

2018 ◽

Vol 40 (1) ◽

pp. 194-201

Author(s):

Joseph L Sottnik ◽

Vandana Mallaredy ◽

Ana Chauca-Diaz ◽

Carolyn Ritterson Lew ◽

Charles Owens ◽

...

Keyword(s):

Glycogen Storage Disease Type ◽

Gene Signature ◽

Glycogen Storage ◽

Genetically Engineered ◽

Normal Bladder ◽

Populations At Risk ◽

Genetically Engineered Mice ◽

Patient Prognosis ◽

The Impact

AbstractAmylo-α-1,6-glucosidase,4-α-glucanotransferase (AGL) is an enzyme primarily responsible for glycogen debranching. Germline mutations lead to glycogen storage disease type III (GSDIII). We recently found AGL to be a tumor suppressor in xenograft models of human bladder cancer (BC) and low levels of AGL expression in BC are associated with poor patient prognosis. However, the impact of low AGL expression on the susceptibility of normal bladder to carcinogenesis is unknown. We address this gap by developing a germline Agl knockout (Agl−/−) mouse that recapitulates biochemical and histological features of GSDIII. Agl−/− mice exposed to N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) had a higher BC incidence compared with wild-type mice (Agl+/+). To determine if the increased BC incidence observed was due to decreased Agl expression in the urothelium specifically, we developed a urothelium-specific conditional Agl knockout (Aglcko) mouse using a Uroplakin II-Cre allele. BBN-induced carcinogenesis experiments repeated in Aglcko mice revealed that Aglcko mice had a higher BC incidence than control (Aglfl/fl) mice. RNA sequencing revealed that tumors from Agl−/− mice had 19 differentially expressed genes compared with control mice. An ‘Agl Loss’ gene signature was developed and found to successfully stratify normal and tumor samples in two BC patient datasets. These results support the role of AGL loss in promoting carcinogenesis and provide a rationale for evaluating Agl expression levels, or Agl Loss gene signature scores, in normal urothelium of populations at risk of BC development such as older male smokers.

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TGF-β Signaling and the Epithelial-Mesenchymal Transition during Palatal Fusion

International Journal of Molecular Sciences ◽

10.3390/ijms19113638 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3638 ◽

Cited By ~ 8

Author(s):

Akira Nakajima ◽

Charles F. Shuler ◽

Alexander Gulka ◽

Jun-ichi Hanai

Keyword(s):

Cell Fate ◽

Transforming Growth Factor ◽

Epithelial Mesenchymal Transition ◽

Genetically Engineered ◽

Fusion Process ◽

Mesenchymal Transition ◽

Morphological Process ◽

Palatal Fusion ◽

Genetically Engineered Mice

Signaling by transforming growth factor (TGF)-β plays an important role in development, including in palatogenesis. The dynamic morphological process of palatal fusion occurs to achieve separation of the nasal and oral cavities. Critically and specifically important in palatal fusion are the medial edge epithelial (MEE) cells, which are initially present at the palatal midline seam and over the course of the palate fusion process are lost from the seam, due to cell migration, epithelial-mesenchymal transition (EMT), and/or programed cell death. In order to define the role of TGF-β signaling during this process, several approaches have been utilized, including a small interfering RNA (siRNA) strategy targeting TGF-β receptors in an organ culture context, the use of genetically engineered mice, such as Wnt1-cre/R26R double transgenic mice, and a cell fate tracing through utilization of cell lineage markers. These approaches have permitted investigators to distinguish some specific traits of well-defined cell populations throughout the palatogenic events. In this paper, we summarize the current understanding on the role of TGF-β signaling, and specifically its association with MEE cell fate during palatal fusion. TGF-β is highly regulated both temporally and spatially, with TGF-β3 and Smad2 being the preferentially expressed signaling molecules in the critical cells of the fusion processes. Interestingly, the accessory receptor, TGF-β type 3 receptor, is also critical for palatal fusion, with evidence for its significance provided by Cre-lox systems and siRNA approaches. This suggests the high demand of ligand for this fine-tuned signaling process. We discuss the new insights in the fate of MEE cells in the midline epithelial seam (MES) during the palate fusion process, with a particular focus on the role of TGF-β signaling.

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Antiatherogenic role of high-density lipoproteins: insights from genetically engineered-mice

Frontiers in Bioscience ◽

10.2741/1887 ◽

2006 ◽

Vol 11 (1) ◽

pp. 1328 ◽

Cited By ~ 15

Author(s):

Joan Carles Escola-Gil

Keyword(s):

Genetically Engineered ◽

High Density ◽

High Density Lipoproteins ◽

Genetically Engineered Mice

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Pancreas-Specific ARID1A Deficiency Promotes Acinar-to-Ductal Metaplasia and Elevates Interleukin-6 Expression in Experimental Pancreatitis Model

10.21203/rs.3.rs-326796/v1 ◽

2021 ◽

Author(s):

Liming Zhang ◽

Zhaoyun Li ◽

Yong Zhou ◽

Jie Zhu ◽

Chong Jin ◽

...

Keyword(s):

Acute Pancreatitis ◽

Epigenetic Regulation ◽

Interleukin 6 ◽

Ex Vivo ◽

Acinar Cells ◽

Genetically Engineered ◽

Ductal Cells ◽

Inflammatory Conditions ◽

Acinar To Ductal Metaplasia

Abstract Background: Although role of ARID1A in pancreatic homeostasis and tumorigenesis has been recently described using genetically engineered mouse (GEM) models, whether ARID1A plays a role in pancreatic inflammation and regeneration remains to be explored.Methods: Pancreas-specific Arid1a-deficient GEM model (Arid1adef) was generated by Ela1-Cre/ERT2 mice crossing with Arid1afl/fl mice and characterized histologically. In physiological and inflammatory conditions, serum amylase and lipase activity were measured to investigate effects of Arid1a deficiency on pancreatic secretion function. Histology analysis of pancreas was used to evaluate pancreatic lesions and recovery. Ex vivo primary acinar cell culture was employed to study acinar-to-ductal metaplasia (ADM) process. In HPNE cells, ARID1A knockdown and histone acetyltransferases inhibitors were used to explore epigenetic regulation on interleukin-6 (IL6) expression. Chromatin immunoprecipitation (ChIP) and quantitative real-time PCR were performed to analyze on IL6 promoters.Results: Arid1a deficiency promoted formation of ductal cysts characterized as silenced acinar genes and activated duct genes. Arid1a-deficient acinar cells were more inclined to trans-differentiation to ductal cells in cerulein-induced acute pancreatitis (AP) model. Expression analysis of proinflammatory cytokines reveals that ARID1A deficiency led to increased IL-6 expression in mice acinar cells and HPNE cells. ARID1A-associated histone acetylation partially involved in epigenetic regulation of IL-6. Conclusion: These results demonstrate ARID1A is involved in cerulein-induced AP development by mediating pro-inflammatory cytokines IL-6 and suggest that ARID1A-containing SWI/SNF complex is an epigenetic regulator of acute pancreatitis.

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Abstract P212: Sphingolipid De Novo Pathway is a Novel Regulator of Blood Pressure Homeostasis

Hypertension ◽

10.1161/hyp.68.suppl_1.p212 ◽

2016 ◽

Vol 68 (suppl_1) ◽

Author(s):

Anna Cantalupo ◽

Yi Zhang ◽

Xian-Cheng Jiang ◽

Annarita Di Lorenzo

Keyword(s):

Blood Pressure ◽

Endothelial Cells ◽

High Blood Pressure ◽

Vascular Reactivity ◽

De Novo ◽

Ex Vivo ◽

Mesenteric Arteries ◽

Serine Palmitoyltransferase ◽

Sphingosine 1 Phosphate

Background and objectives: Sphingolipids, particularly sphingosine 1-phosphate (S1P), play an important role in the cardiovascular homeostasis. Recently, we revealed that endothelial de novo biosynthesis of sphingolipids is very important to control vascular functions and blood pressure. We discovered that in blood vessels, particularly in endothelial cells, Nogo-B, a membrane protein of the endoplasmic reticulum, inhibits serine palmitoyltransferase (SPT), the first and rate-limiting enzyme of de novo production of sphingolipids, to impact vascular tone and blood pressure. Indeed, mice lacking Nogo-B are protected from angiotensin II-induced hypertension, and pharmacological inhibition of SPT by myriocin reinstates high blood pressure in absence of Nogo-B, suggesting that the upregulation of SPT activity exerts anti-hypertensive functions. Thus, the goal of this study is to investigate the role of SPT in vascular functions and blood pressure regulation by using novel genetic mouse models. Methods: The SBP was evaluated in 14 weeks old mice heterozygous for Sptlc2 ( Sptlc2 +/- ) or lacking Sptlc2 specifically in endothelial cells (ECKO Sptlc2 ) and smooth muscle cells (SMCKO Sptlc2 ) by using tail-cuff system. Vascular reactivity of isolated mesenteric arteries was assessed ex-vivo by using the pressure myograph system. Results: Sptlc2 +/- , ECKO Sptlc2 and SMCKO Sptlc2 mice were hypertensive compared to their respective controls ( Sptlc2 +/- 128.9±2.6 vs. WT 112.1±2.6 mmHg; ECKO Sptlc2 125.5±1.8, SMCKO Sptlc2 127.2±0.6 vs. Sptlc2 f/f 106±0.84 mmHg) and developed endothelial dysfunction as shown by the impaired vasodilation in response to acetylcholine (EC 50 Sptlc2 +/- 1.48x10 -6 M vs. WT 4.46x10 -7 M; Emax ECKO Sptlc2 73.2±3.3% vs. Sptlc2 f/f 95.3±1.1%), as well as to flow (Emax: Sptlc2 +/- 23.3±1.4 μm vs. WT 42.9±4.4 μm; ECKO Sptlc2 19.9±0.9 μm vs. Sptlc2 f/f 41.3±3.1 μm). Conclusion: This study demonstrates the important role of SPT, thus the de novo production of sphingolipids, in controlling blood flow and pressure homeostasis, and provides the ground for the development of alternative therapeutic strategies to manage high blood pressure.

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Abstract 584: Smooth Muscle Cell-derived IL-17C Plays an Atherogenic Role via the Recruitment of Pro-inflammatory IL-17A + T Cells to the Aorta

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.36.suppl_1.584 ◽

2016 ◽

Vol 36 (suppl_1) ◽

Author(s):

Matthew J Butcher ◽

Tayab C Waseem ◽

Elena V Galkina

Keyword(s):

T Cells ◽

Smooth Muscle ◽

Smooth Muscle Cell ◽

Muscle Cell ◽

Th17 Cells ◽

Ex Vivo ◽

Flow Cytometric Analysis ◽

Atherosclerotic Lesion ◽

Atherosclerotic Lesions

Atherosclerosis is characterized by frequent communication between infiltrating leukocytes and vascular cells, through chemokine and cytokine networks. IL-17 cytokine family members, including IL-17C, are detectable within atherosclerotic plaques, however the potential involvement of these cytokines have not been examined. Thus we sought to investigate the role of IL-17C in atherosclerosis. The expression of IL-17 cytokines was profiled within atherosclerotic Apoe -/- aortas and Il17c expression was elevated. Flow cytometry experiments revealed a major population of aortic IL-17C-producing smooth muscle cells. To determine the role of IL-17C in atherosclerosis, we generated Il17c -/- Apoe -/- mice and compared atherosclerotic lesions between western diet-fed Apoe -/- and Il17c -/- Apoe -/- mice. Atherosclerotic lesion and collagen content was diminished within WD-fed Il17c -/- Apoe -/- aortas and aortic roots in comparison to Apoe -/- controls, and IL-17C treated Apoe -/- aortas up-regulated Col1A1 expression ex vivo . Flow cytometric analysis of Il17c -/- Apoe -/- aortas revealed a proportional reduction in aortic leukocytes, macrophages, neutrophils, T cells, Th1, and T regulatory cells, without corresponding changes in the peripheral immune composition. Examination of aortic IL-17A + TCRγδ T cells and Th17 cells demonstrated a stark reduction in the percentage and number of these subsets within Il17c -/- Apoe -/- mice versus Apoe -/- controls. Explanted 12 week WD Apoe -/- aortas treated with IL-17C resulted in the induction of multiple vascular chemokines and cytokines, and short-term homing experiments revealed diminished recruitment of Th17 cells to the aorta of Il17c -/- Apoe -/- recipients. Smooth muscle cell-derived IL-17C plays a pro-atherogenic role by supporting the recruitment of Th17 cells to atherosclerotic lesions.

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Abstract 509: Essential Role of Vascular Smooth Muscle Bmal1 in Diurnal Variations of Contraction and Blood Pressure

Hypertension ◽

10.1161/hyp.60.suppl_1.a509 ◽

2012 ◽

Vol 60 (suppl_1) ◽

Author(s):

Wen Su ◽

Zhongwen Xie ◽

Zhenheng Guo ◽

Ming C Gong

Keyword(s):

Blood Pressure ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Essential Role ◽

Smooth Muscle Contraction ◽

Diurnal Variations ◽

Mesenteric Arteries ◽

Isometric Contractions ◽

Vascular Smooth Muscle Contraction

Bmal1 is an obligatory core clock gene that is ubiquitously expressed but has been demonstrated to have tissue specific functions. However, the vascular smooth muscle specific function of bmal1 is unknown. We generated a smooth muscle specific bmal1 knockout mouse model (SM-bmal1-ko) and investigated the role of bmal1 in vascular smooth muscle contraction and blood pressure regulation. Isometric contractions were measured in isolated right renal artery and 2 nd order branch of mesenteric artery helical strips. Blood pressure was monitored in conscious free-moving mice using radiotelemetry. We demonstrated that bmal1 was selectively deleted in smooth muscle enriched tissues like mesenteric arteries. Moreover, the diurnal variations of bmal1 target genes per1/2 were abolished in mesenteric arteries. The isometric contractions in response to alpha1 agonist phenylephrine and to 5-HT were significantly diminished in vascular helical strips isolated from SM-bmal1-ko mice compared to that from control flox mice. The contractile diurnal variations detected in the renal arteries isolated from control flox mice were significantly diminished in samples isolated from SM-bmal1-ko mice. Moreover, in vivo , the diurnal variations in the instantaneous pressor responses to intravenous phenylephrine injection were significantly diminished in SM-bmal1-ko mice compared to control flox mice. Twenty four hour mean arterial blood pressure was significantly decreased under 12:12 light:dark, constant light or constant dark conditions. Importantly, the amplitude of blood pressure diurnal variations was significantly diminished in SM-bmal1-ko mice. Importantly, neither the level nor the diurnal variations of locomotor activity was affected by bmal1 deletion. This indicates that the central SCN clock function is not affected in the SM-bmal1-ko mice and the blood pressure alterations in SM-bmal1-ko mice is not a consequence of changed locomotor activity. Taken together, our results demonstrate an essential role of bmal1 in the diurnal variations of vascular smooth muscle contraction and blood pressure.

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