scholarly journals The Modulatory Effect of Ischemia and Reperfusion on Arginine Vasopressin-Induced Arterial Reactions

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Katarzyna Szadujkis-Szadurska ◽  
Bartosz Malinowski ◽  
Małgorzata Piotrowska ◽  
Grzegorz Grześk ◽  
Michał Wiciński ◽  
...  

Aim of the Study.The purpose of this study was to investigate the impact of ischemia and reperfusion on the resistance of arteries to AVP (arginine vasopressin), with a particular emphasis on the role of smooth muscle cells in the action of vasopressin receptors and the role of the cGMP-associated signalling pathway.Materials and Methods.Experiment was performed on the perfunded tail arteries from male Wistar rats. The constriction triggered by AVP after 30 minutes of ischemia and 30 and 90 minutes of reperfusion was analysed. Analogous experiments were also carried out in the presence of 8Br-cGMP.Results.Ischemia reduces and reperfusion increases in a time-dependent manner the arterial reaction to AVP. The presence of 8Br-cGMP causes a significant decrease of arterial reactivity under study conditions.Conclusions.Ischemia and reperfusion modulate arterial contraction triggered by AVP. The effect of 8Br-cGMP on reactions, induced by AVP after ischemia and reperfusion, indicates that signalling pathway associated with nitric oxide (NO) and cGMP regulates the tension of the vascular smooth muscle cells.

2002 ◽  
Vol 282 (2) ◽  
pp. G226-G232 ◽  
Author(s):  
Hirotada Akiho ◽  
Patricia Blennerhassett ◽  
Yikang Deng ◽  
Stephen M. Collins

T helper 2 (Th2) cytokines interleukin (IL)-4 and IL-13, which activate signal transducer and activator of transcription 6 (STAT6) are expressed in the muscularis externa during nematode infection and are candidate mediators of the associated hypercontractility. To determine the locus of action of these cytokines, we examined the IL-4- and IL-13-induced hypercontractility of the isolated muscle cells from STAT6 +/+ and STAT6 −/− mice. We compared the results with cells isolated from Trichinella spiralis-infected STAT6 +/+ and STAT6 −/− mice. Carbamylcholine chloride (Carbachol) induced the contraction of jejunal muscle cells in a concentration-dependent manner maximal contraction (Rmax26.7 ± 1.9%). Cells from T. spiralis-infected STAT6 −/− mice showed the hypertrophy (cell lengths 41.4 ± 0.8 to 89.0 ± 8.7 μm) and hypercontractility (Rmax37.5 ± 1.3%) induced by infection. IL-4Rα mRNA was detected in dispersed smooth muscle cells. Incubation of longitudinal muscle-myenteric plexus (LMMP) with IL-4 and IL-13 enhanced Carbachol-induced muscle contraction (Rmax35.5 ± 1.9 and 32.4 ± 2.9%, respectively). Incubation of LMMP from STAT6 −/− mice with IL-4 did not enhance the contraction. The hypercontractility in T. spiralis-infected mice was attenuated in STAT6 −/− mice ( P < 0.02). These results indicate both IL-4 and IL-13 induce hypercontractility of muscle cells via the STAT6 pathway, and this is the basis for hypercontractility observed in T. spiralis-infected mice.


Author(s):  
Soo-jin Ann ◽  
Hyoeun Bang ◽  
Chan Joo Lee ◽  
Jaewon Oh ◽  
Sungha Park ◽  
...  

AbstractAlthough there are many genetic loci in noncoding regions associated with vascular disease, studies on long noncoding RNAs (lncRNAs) discovered from human plaques that affect atherosclerosis have been highly limited. We aimed to identify and functionally validate a lncRNA using human atherosclerotic plaques. Human aortic samples were obtained from patients who underwent aortic surgery, and tissues were classified according to atherosclerotic plaques. RNA was extracted and analyzed for differentially expressed lncRNAs in plaques. Human aortic smooth muscle cells (HASMCs) were stimulated with oxidized low-density lipoprotein (oxLDL) to evaluate the effect of the identified lncRNA on the inflammatory transition of the cells. Among 380 RNAs differentially expressed between the plaque and control tissues, lncRNA HSPA7 was selected and confirmed to show upregulated expression upon oxLDL treatment. HSPA7 knockdown inhibited the migration of HASMCs and the secretion and expression of IL-1β and IL-6; however, HSPA7 knockdown recovered the oxLDL-induced reduction in the expression of contractile markers. Although miR-223 inhibition promoted the activity of Nf-κB and the secretion of inflammatory proteins such as IL-1β and IL-6, HSPA7 knockdown diminished these effects. The effects of miR-223 inhibition and HSPA7 knockdown were also found in THP-1 cell-derived macrophages. The impact of HSPA7 on miR-223 was mediated in an AGO2-dependent manner. HSPA7 is differentially increased in human atheroma and promotes the inflammatory transition of vascular smooth muscle cells by sponging miR-223. For the first time, this study elucidated the molecular mechanism of action of HSPA7, a lncRNA of previously unknown function, in humans.


2006 ◽  
Vol 290 (4) ◽  
pp. L747-L753 ◽  
Author(s):  
Cornelius J. Busch ◽  
Heling Liu ◽  
Amanda R. Graveline ◽  
Kenneth D. Bloch

Phosphodiesterases (PDE) metabolize cyclic nucleotides limiting the effects of vasodilators such as prostacyclin and nitric oxide (NO). In this study, DNA microarray techniques were used to assess the impact of NO on expression of PDE genes in rat pulmonary arterial smooth muscle cells (rPASMC). Incubation of rPASMC with S-nitroso-l-glutathione (GSNO) increased expression of a PDE isoform that specifically metabolizes cAMP (PDE4B) in a dose- and time-dependent manner. GSNO increased PDE4B protein levels, and rolipram-inhibitable PDE activity was 2.3 ± 1.0-fold greater in GSNO-treated rPASMC than in untreated cells. The soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one, and the cAMP-dependent protein kinase inhibitor, H89, prevented induction of PDE4B gene expression by GSNO, but the protein kinase G (PKG) inhibitors, Rp-8-pCPT-cGMPs and KT-5823, did not. Incubation of rPASMC with IL-1β and tumor necrosis factor-α induced PDE4B gene expression, an effect that was inhibited by l- N6-(1-iminoethyl)lysine, an antagonist of NO synthase 2 (NOS2). The GSNO-induced increase in PDE4B mRNA levels was blocked by actinomycin D but augmented by cycloheximide. Infection of rPASMC with an adenovirus specifying a dominant negative cAMP response element binding protein (CREB) mutant inhibited the GSNO-induced increase of PDE4B gene expression. These results suggest that exposure of rPASMC to NO induces expression of PDE4B via a mechanism that requires cGMP synthesis by sGC but not PKG. The GSNO-induced increase of PDE4B gene expression is CREB dependent. These findings demonstrate that NO increases expression of a cAMP-specific PDE and provide evidence for a novel “cross talk” mechanism between cGMP and cAMP signaling pathways.


2021 ◽  
Author(s):  
Jorge A. Aguilar-Pineda ◽  
Karin J. Vera-Lopez ◽  
Pallavi Shrivastava ◽  
Rita Nieto-Montesinos ◽  
Miguel A. Chávez-Fumagalli ◽  
...  

SUMMARYDespite the emerging evidence implying early vascular contributions to neurogenerative syndromes, the role of vascular smooth muscle cells (VSMCs) in the pathogenesis of Alzheimer’s disease is still not well understood. Herein, we show that VSMCs in brains of AD patients and the animal model of the disease, are deficient in multiple VSMC-contractile markers which correlated with Tau accumulation in brain arterioles. Ex vivo and in vitro experiments demonstrated that VSMCs undergo dramatic phenotypic transitions under AD-like conditions, adopting pro-inflammatory and synthetic phenotypes. Notably, these changes coincided with Tau hyperphosphorylation at residues Y18, T205 and S262. We also observed that loss of VSMC markers occurred in an age-dependent manner, and that expression of Sm22α and α-Sma proteins were inversely correlated with CD68 and Tau accumulation in brain arterioles of 3xTg-AD mice. Together, these findings further support the contribution of VSMCs in AD pathogenesis, and nominate VSMCs as potential novel therapeutic target in AD.Graphical Abstract


2021 ◽  
Vol 23 (1) ◽  
pp. 375
Author(s):  
Antonio Tejera-Muñoz ◽  
Laura Marquez-Exposito ◽  
Lucía Tejedor-Santamaría ◽  
Sandra Rayego-Mateos ◽  
Macarena Orejudo ◽  
...  

The cellular communication network factor 2 (CCN2/CTGF) has been traditionally described as a mediator of the fibrotic responses induced by other factors including the transforming growth factor β (TGF-β). However, several studies have defined a direct role of CCN2 acting as a growth factor inducing oxidative and proinflammatory responses. The presence of CCN2 and TGF-β together in the cellular context has been described as a requisite to induce a persistent fibrotic response, but the precise mechanisms implicated in this relation are not described yet. Considering the main role of TGF-β receptors (TβR) in the TGF-β pathway activation, our aim was to investigate the effects of CCN2 in the regulation of TβRI and TβRII levels in vascular smooth muscle cells (VSMCs). While no differences were observed in TβRI levels, an increase in TβRII expression at both gene and protein level were found 48 h after stimulation with the C-terminal fragment of CCN2 (CCN2(IV)). Cell pretreatment with a TβRI inhibitor did not modify TβRII increment induced by CCN2(VI), demonstrating a TGF-β-independent response. Secondly, CCN2(IV) rapidly activated the SMAD pathway in VSMCs, this being crucial in the upregulation of TβRII since the preincubation with an SMAD3 inhibitor prevented it. Similarly, pretreatment with the epidermal growth factor receptor (EGFR) inhibitor erlotinib abolished TβRII upregulation, indicating the participation of this receptor in the observed responses. Our findings suggest a direct role of CCN2 maintaining the TGF-β pathway activation by increasing TβRII expression in an EGFR-SMAD dependent manner activation.


Pneumologie ◽  
2014 ◽  
Vol 68 (06) ◽  
Author(s):  
A Moiseenko ◽  
E El Agha ◽  
B MacKenzie ◽  
S De Langhe ◽  
S Bellusci

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