scholarly journals Contrasting Roles of Ang II and ACEA in the Regulation of IL10 and IL1β Gene Expression in Primary SHR Astroglial Cultures

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 3012
Author(s):  
Dhanush Haspula ◽  
Michelle A. Clark

Angiotensin (Ang) II is well-known to have potent pro-oxidant and pro-inflammatory effects in the brain. Extensive crosstalk between the primary Ang II receptor, Ang type 1 receptor (AT1R), and the cannabinoid type 1 receptor (CB1R) has been demonstrated by various groups in the last decade. Since activation of glial CB1R has been demonstrated to play a key role in the resolution of inflammatory states, we investigated the role of Ang II (100 nM) and/or ACEA (10 nM), a potent CB1R-specific agonist in the regulation of inflammatory markers in astrocytes from spontaneously hypertensive rats (SHR) and Wistar rats. Astrocytes were cultured from brainstems and cerebellums of SHR and Wistar rats and assayed for IL1β and IL10 gene expression and secreted fraction, in treated and non-treated cells, by employing qPCR and ELISA, respectively. mRNA expression of both IL10 and IL1β were significantly elevated in untreated brainstem and cerebellar astrocytes isolated from SHR when compared to Wistar astrocytes. No changes were observed in the secreted fraction. While ACEA-treatment resulted in a significant increase in IL10 gene expression in Wistar brainstem astrocytes (Log2FC ≥ 1, p < 0.05), its effect in SHR brainstem astrocytes was diminished. Ang II treatment resulted in a strong inhibitory effect on IL10 gene expression in astrocytes from both brain regions of SHR and Wistar rats (Log2FC ≤ −1, p < 0.05), and an increase in IL1β gene expression in brainstem astrocytes from both strains (Log2FC ≥ 1, p < 0.05). Co-treatment of Ang II and ACEA resulted in neutralization of Ang II-mediated effect in Wistar brainstem and cerebellar astrocytes, but not SHR astrocytes. Neither Ang II nor ACEA resulted in any significant changes in IL10 or IL1β secreted proteins. These data suggest that Ang II and ACEA have opposing roles in the regulation of inflammatory gene signature in astrocytes isolated from SHR and Wistar rats. This however does not translate into changes in their secreted fractions.

2000 ◽  
Vol 279 (6) ◽  
pp. H2939-H2946 ◽  
Author(s):  
Hiroshi Yamakawa ◽  
Takuroh Imamura ◽  
Takeshi Matsuo ◽  
Hisamitsu Onitsuka ◽  
Yoko Tsumori ◽  
...  

We investigated the effects of diastolic wall stress (WS) and angiotensin II (ANG II) on the left ventricular (LV) hypertrophy (LVH) induced by volume overload and on the gene expression of LV adrenomedullin (AM) and atrial natriuretic peptide (ANP) in volume overload. Diastolic WS was pharmacologically manipulated with (candesartan) or without (calcium channel blocker manidipine) inhibition of ANG II type 1 receptors in aortocaval-shunted rats over 6 wk. Diastolic WS reached a plateau at 2 wk and subsequently declined regardless of further LVH. Although diastolic WS was decreased to a similar extent by both compounds, candesartan blunted LVH over 6 wk, whereas manidipine blunted LVH at 2 wk but not after 4 wk. Levels of AM and ANP gene expression increased as LVH developed but were completely suppressed by candesartan over 6 wk. ANP expression level was also attenuated by manidipine over 6 wk, whereas AM expression level was suppressed at 2 wk but not after 4 wk by manidipine. We concluded that diastolic WS and ANG II might be potent stimuli for the LVH and LV AM and ANP gene expression in volume overload and that diastolic WS could be relatively involved in the early LVH and in the gene expression of ANP rather than of AM.


2006 ◽  
Vol 291 (4) ◽  
pp. E771-E778 ◽  
Author(s):  
Kyoichiro Tsuchiya ◽  
Takanobu Yoshimoto ◽  
Yuki Hirono ◽  
Toru Tateno ◽  
Toru Sugiyama ◽  
...  

Both monocyte chemoattractant protein-1 (MCP-1), a member of chemokine family, and angiotensinogen, a precursor of angiotensin (ANG) II, are produced by adipose tissue and increased in obese state. MCP-1 has been shown to decrease insulin-stimulated glucose uptake and several adipogenic genes expression in adipocytes in vitro, suggesting its pathophysiological significance in obesity. However, the pathophysiological interaction between MCP-1 and ANG II in adipose tissue remains unknown. The present study was undertaken to investigate the potential mechanisms by which ANG II affects MCP-1 gene expression in rat primary cultured preadipocytes and adipose tissue in vivo. ANG II significantly increased steady-state MCP-1 mRNA levels in a time- and dose-dependent manner. The ANG II-induced MCP-1 mRNA and protein expression was completely abolished by ANG II type 1 (AT1)-receptor antagonist (valsartan). An antioxidant/NF-κB inhibitor (pyrrolidine dithiocarbamate) and an inhibitor of 1κB-α phosphorylation (Bay 11-7085) also blocked ANG II-induced MCP-1 mRNA expression. ANG II induced translocation of NF-κB p65 subunit from cytoplasm to nucleus by immunocytochemical study. Luciferase assay using reporter constructs containing MCP-1 promoter region revealed that two NF-κB binding sites in its enhancer region were essential for the ANG II-induced promoter activities. Furthermore, basal mRNA and protein of MCP-1 during preadipocyte differentiation were significantly greater in preadipocytes than in differentiated adipocytes, whose effect was more pronounced in the presence of ANG II. Exogenous administration of ANG II to rats led to increased MCP-1 expression in epididymal, subcutaneous, and mesenteric adipose tissue. In conclusion, our present study demonstrates that ANG II increases MCP-1 gene expression via ANG II type 1 receptor-mediated and NF-κB-dependent pathway in rat preadipocytes as well as adipose MCP-1 expression in vivo. Thus the augmented MCP-1 expression by ANG II in preadipocytes may provide a new link between obesity and cardiovascular disease.


2004 ◽  
Vol 18 (3) ◽  
pp. 331-339 ◽  
Author(s):  
Dan Zhou ◽  
Jin Xue ◽  
Orit Gavrialov ◽  
Gabriel G. Haddad

Na+/H+ exchanger 1 (NHE1) is well known to function as a major regulator of intracellular pH (pHi). It is activated by low pHi and exchanges extracellular Na+ for intracellular H+ to maintain cellular homeostasis. Despite the fact that we now have evidence suggesting other roles for NHE1, there has been no comprehensive study investigating its role as a signaling molecule. Toward this aim, we used in this study NHE1 null mutant mice and cDNA microarrays to investigate the effects of NHE1 on global gene expression in various regions of the brain, e.g., cortex, hippocampus, brain stem-diencephalon, and cerebellum. We found that a total of 35 to 79 genes were up- or downregulated in each brain region, with the majority being downregulated. The effect of NHE1 null mutation on gene expression is region specific, and only 11 genes were changed in all brain regions studied. Further analysis of the cis-regulatory regions of downregulated genes revealed that transcription suppressors, BCL6 and E4BP4, were probable candidates that mediated the inhibitory effect of NHE1 null mutation. One of the genes, MCT-13, was not only downregulated in the NHE1 null mutant brain but also in tissue cultures treated with an NHE1 inhibitor. We conclude that 1) a relatively small number of genes were altered in the NHE1 null mouse brain; 2) the effects of NHE1 null mutation on gene expression are region specific; and 3) several genes implicated in neurodegeneration have altered expression, potentially offering a molecular explanation for the phenotype of the NHE1 null mouse.


2006 ◽  
Vol 291 (2) ◽  
pp. E221-E233 ◽  
Author(s):  
John R. Pepperell ◽  
Gabor Nemeth ◽  
Yuji Yamada ◽  
Frederick Naftolin ◽  
Maricruz Merino

These studies aim to investigate subcellular distribution of angiotensin II (ANG II) in rat luteal cells, identify other bioactive angiotensin peptides, and investigate a role for angiotensin peptides in luteal steroidogenesis. Confocal microscopy showed ANG II distributed within the cytoplasm and nuclei of luteal cells. HPLC analysis showed peaks that eluted with the same retention times as ANG-(1–7), ANG II, and ANG III. Their relative concentrations were ANG II ≥ ANG-(1–7) > ANG III, and accumulation was modulated by quinapril, an inhibitor of angiotensin-converting enzyme (ACE), Z-proprolinal (ZPP), an inhibitor of prolyl endopeptidase (PEP), and parachloromercurylsulfonic acid (PCMS), an inhibitor of sulfhydryl protease. Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, did not affect peptide accumulation. Quinapril, ZPP, PCMS, and PMSF, as well as losartan and PD-123319, the angiotensin receptor type 1 (AT1) and type 2 (AT2) receptor antagonists, were used in progesterone production studies. ZPP significantly reduced luteinizing hormone (LH)-dependent progesterone production ( P < 0.05). Quinapril plus ZPP had a greater inhibitory effect on LH-stimulated progesterone than either inhibitor alone, but this was not reversed by exogenous ANG II or ANG-(1–7). Both PCMS and PMSF acutely blocked LH-stimulated progesterone, and PCMS blocked LH-sensitive cAMP accumulation. Losartan inhibited progesterone production in permeabilized but not intact luteal cells and was reversed by ANG II. PD-123319 had no significant effect on luteal progesterone production in either intact or permeabilized cells. These data suggest that steroidogenesis may be modulated by angiotensin peptides that act in part through intracellular AT1 receptors.


2007 ◽  
Vol 35 (4) ◽  
pp. 482-489 ◽  
Author(s):  
T Matsui ◽  
S Yamagishi ◽  
S Ueda ◽  
K Nakamura ◽  
T Imaizumi ◽  
...  

Interaction between advanced glycation end-products (AGEs) and their receptor (RAGE) plays a central role in diabetic nephropathy pathogenesis. Pathophysiological crosstalk between the AGEs–RAGE system and angiotensin II (Ang II) is also involved in this disease. This study investigated the role of proliferator-activated receptor-γ (PPAR-γ)-modulating activity on inhibition of monocyte chemoattractant protein (MCP-1) expression. Telmisartan, an Ang II type 1 receptor blocker, downregulated RAGE mRNA and inhibited superoxide generation and MCP-1 gene expression in mesangial cells; these processes were blocked by GW9662, a PPAR-γ inhibitor. Candesartan, an Ang II type 1 receptor blocker, did not suppress AGEs-induced superoxide generation. Telmisartan and the antioxidant, N-acetylcysteine, completely inhibited AGEs-induced MCP-1 overproduction by mesangial cells. These results suggest that telmisartan inhibits AGEs-signalling to MCP-1 expression in mesangial cells by downregulating RAGE gene expression and subsequent oxidative stress generation via PPAR-γ activation. This study has demonstrated a unique benefit of telmisartan in that it may function as an anti-inflammatory agent against AGEs via PPAR-γ activation and may play a protective role in diabetic nephropathy.


2003 ◽  
Vol 77 (12) ◽  
pp. 6777-6784 ◽  
Author(s):  
Theresa Li-Yun Chang ◽  
Fleur François ◽  
Arevik Mosoian ◽  
Mary E. Klotman

ABSTRACT CD8+ T lymphocytes can inhibit human immunodeficiency virus type 1 (HIV-1) replication by secreting a soluble factor(s) known as CD8+ T-lymphocyte antiviral factor (CAF). One site of CAF action is inhibition of HIV-1 RNA transcription, particularly at the step of long terminal repeat (LTR)-driven gene expression. The inhibitory effect of CAF on HIV-1 LTR activation is mediated through STAT1 activation. A recent study reports that α-defensins 1 to 3 account for CAF activity against HIV-1. Here, we address whether α-defensins, particularly α-defensin-1, contribute to CAF-mediated inhibition of HIV-1 transcription. Both recombinant α-defensin-1 and CAF derived from herpesvirus saimiri (HVS)-transformed CD8+ cells inhibited HIV-1 infection and gene expression. For both factors, the inhibition of HIV-1 infection did not occur at the level of viral entry. Pretreatment of cells with α-defensin-1 followed by a washing out prior to infection blocked infection by HIV-1, indicating that direct inactivation of virions was not required for its inhibitory effect. In contrast to CAF, α-defensin-1 did not inhibit phorbol myristate acetate- or Tat-mediated HIV-1 LTR activation in a transient transfection system, nor did it activate STAT1 tyrosine phosphorylation. Furthermore, α-defensins 1 to 3 were below the level of detection in a panel of HVS-transformed CD8+ cells with potent HIV-1 inhibitory activity and a neutralizing antibody against α-defensins 1 to 3 did not reverse the inhibitory effect of CAF on HIV-1 gene expression in infected cells and on HIV-1 LTR activation in transfected cells. Taken together, our results suggest that α-defensin-1 inhibits HIV-1 infection following viral entry but that α-defensins 1 to 3 are not responsible for the HIV-1 transcriptional inhibition by CAF.


2003 ◽  
Vol 104 (2) ◽  
pp. 109-118 ◽  
Author(s):  
Richard D. PATTEN ◽  
Mark J. ARONOVITZ ◽  
Michael EINSTEIN ◽  
Matthew LAMBERT ◽  
Natesa G. PANDIAN ◽  
...  

Left ventricular (LV) remodelling following myocardial infarction (MI) is associated with increased morbidity and mortality. Previous data suggest that angiotensin II (Ang II) plays a central role in the molecular events contributing to LV remodelling. We explored the effects of angiotensin-converting-enzyme (ACE) inhibition versus Ang II (AT1) receptor blockade on LV remodelling in mice post-MI. Mice underwent sham procedure or left coronary artery ligation, and received placebo, the AT1 receptor antagonist, losartan or the ACE inhibitor, enalapril. At 6 weeks, echocardiography and haemodynamic studies were performed. Infarct size and interstitial collagen content were determined. Expression of genes encoding atrial natriuretic peptide (ANP), collagen type I, AT1a and AT1b receptors were measured. The placebo MI group showed increased LV end-diastolic diameter, LV end-systolic diameter with depressed fractional shortening (P<0.01 versus shams), increased LV mass and volume (both P<0.01 versus shams). The placebo MI group also exhibited increased non-infarct zone collagen content (P<0.01), ANP (P<0.01) and collagen type 1 (P<0.01) gene expression, with a non-significant rise in AT1a receptor gene expression. Neither losartan or enalapril prevented LV dilation or improved fractional shortening. Both similarly lowered systolic blood pressure (P<0.01 for each versus placebo). Losartan and enalapril inhibited LV hypertrophy (P<0.01), and decreased ANP (P<0.01) and collagen type 1 gene expression (P<0.05). Levels of AT1a receptor gene expression were higher than shams (P<0.05 for both), but similar to placebo. AT1b receptor gene expression was much lower than that for AT1a receptor and similar in all groups. Thus, in this model, AT1 receptor antagonism and ACE inhibition have equivalent inhibitory effects on myocardial hypertrophy and fibrosis. These results serve as an important basis for planned investigations to evaluate the anti-remodelling effects of these agents on mice in which genetic manipulations are used to disrupt components of the Ang II signalling system.


2021 ◽  
pp. 026988112110192
Author(s):  
Ashley M Schnakenberg Martin ◽  
Dae-Jin Kim ◽  
Sharlene D Newman ◽  
Hu Cheng ◽  
William P Hetrick ◽  
...  

Background: Cannabis use has been associated with abnormalities in cerebellar mediated motor and non-motor (i.e. cognition and personality) phenomena. Since the cerebellum is a region with high cannabinoid type 1 receptor density, these impairments may reflect alterations of signaling between the cerebellum and other brain regions. Aims: We hypothesized that cerebellar-cortical resting-state functional connectivity (rsFC) would be altered in cannabis users, relative to their non-using peers. It was also hypothesized that differences in rsFC would be associated with cannabis use features, such as age of initiation and lifetime use. Methods: Cerebellar-cortical and subcortical rsFCs were computed between 28 cerebellar lobules, defined by a spatially unbiased atlas template of the cerebellum, and individual voxels in the cerebral regions, in 41 regular cannabis users (20 female) and healthy non-using peers ( N = 31; 18 female). We also investigated associations between rsFC and cannabis use features (e.g. lifetime cannabis use and age of initiation). Results: Cannabis users demonstrated hyperconnectivity between the anterior cerebellar regions (i.e. lobule I-IV) with the posterior cingulate cortex, and hypoconnectivity between the rest of the cerebellum (i.e. Crus I and II, lobule VIIb, VIIIa, VIIIb, IX, and X) and the cortex. No associations were observed between features of cannabis use and rsFC. Conclusions: Cannabis use was associated with altered patterns of rsFC from the cerebellum to the cerebral cortex which may have a downstream impact on behavior and cognition.


Sign in / Sign up

Export Citation Format

Share Document