scholarly journals Inhibition of the ROS-EGFR Pathway Mediates the Protective Action of Nox1/4 Inhibitor GKT137831 against Hypertensive Cardiac Hypertrophy via Suppressing Cardiac Inflammation and Activation of Akt and ERK1/2

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Si-yu Zeng ◽  
Qiu-jiang Yan ◽  
Li Yang ◽  
Qing-hua Mei ◽  
Hui-qin Lu

Oxidative stress, inflammation, and hypertension constitute a self-perpetuating vicious circle to exacerbate hypertension and subsequent hypertensive cardiac hypertrophy. NADPH oxidase (Nox) 1/4 inhibitor GKT137831 alleviates hypertensive cardiac hypertrophy in models of secondary hypertension; however, it remains unclear about its effect on hypertensive cardiac hypertrophy in models of essential hypertension. This study is aimed at determining the beneficial role of GKT137831 in hypertensive cardiac hypertrophy in spontaneously hypertensive rats (SHRs) and its mechanisms of action. Treating with GKT137831 prevented cardiac hypertrophy in SHRs. Likewise, decreasing production of reactive oxygen species (ROS) with GKT137831 reduced epidermal growth factor receptor (EGFR) activity in the left ventricle of SHRs. Additionally, EGFR inhibition also reduced ROS production in the left ventricle and blunted hypertensive cardiac hypertrophy in SHRs. Moreover, inhibition of the ROS-EGFR pathway with Nox1/4 inhibitor GKT137831 or selective EGFR inhibitor AG1478 reduced protein and mRNA levels of proinflammatory cytokines tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and interleukin 1β (IL-1β), as well as the activities of Akt and extracellular signal-regulated kinase (ERK) 1/2 in the left ventricle of SHRs. In summary, GKT137831 prevents hypertensive cardiac hypertrophy in SHRs, Nox-deprived ROS regulated EGFR activation through positive feedback in the hypertrophic myocardium, and inhibition of the ROS-EGFR pathway mediates the protective role of GKT137831 in hypertensive cardiac hypertrophy via repressing cardiac inflammation and activation of Akt and ERK1/2. This research will provide additional details for GKT137831 to prevent hypertensive cardiac hypertrophy.

2021 ◽  
Vol 8 ◽  
Author(s):  
Liyang Chen ◽  
Qing Tian ◽  
Zhiguang Shi ◽  
Yu Qiu ◽  
Qiulun Lu ◽  
...  

Melatonin (N-acetyl-5-methoxytryptamine) has been shown to have a cardioprotective effect against myocarditis. However, the mechanisms underlying the protective role of melatonin (MLT) in sepsis-induced myocarditis are yet to be revealed. In this study, MLT was administrated to mice, 14 days before cecal ligation puncture surgery. Echocardiography results showed that MLT alleviated cardiac dysfunction in sepsis-induced myocarditis. Furthermore, MLT reduced cardiac inflammation by inhibiting the expression of Il-1α, Il-1β, Il-6, and Mcp-1 messenger RNA (mRNA) levels. The RNA sequencing (RNA-seq) assays with heart tissues showed that MLT maintains the mitochondrial function in sepsis-caused myocarditis. Additionally, the production of reactive oxygen species (ROS) in heart tissues was suppressed by MLT. Taken together, in evaluating the therapeutic effect of MLT on sepsis-induced myocarditis, the results showed that MLT alleviated cardiac damage by regulating mitochondrial function and mitochondrial ROS.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6610
Author(s):  
Ana T. Rufino ◽  
Ana Ramalho ◽  
Adelaide Sousa ◽  
José Miguel P. Ferreira de Oliveira ◽  
Paulo Freitas ◽  
...  

Silver nanoparticles (AgNP) have been increasingly incorporated into food-related and hygiene products for their unique antimicrobial and preservative properties. The consequent oral exposure may then result in unpredicted harmful effects in the gastrointestinal tract (GIT), which should be considered in the risk assessment and risk management of these materials. In the present study, the toxic effects of polyethyleneimine (PEI)-coated AgNP (4 and 19 nm) were evaluated in GIT-relevant cells (Caco-2 cell line as a model of human intestinal cells, and neutrophils as a model of the intestinal inflammatory response). This study also evaluated the putative protective action of dietary flavonoids against such harmful effects. The obtained results showed that AgNP of 4 and 19 nm effectively induced Caco-2 cell death by apoptosis with concomitant production of nitric oxide, irrespective of the size. It was also observed that AgNP induced human neutrophil oxidative burst. Interestingly, some flavonoids, namely quercetin and quercetagetin, prevented the deleterious effects of AgNP in both cell types. Overall, the data of the present study provide a first insight into the promising protective role of flavonoids against the potentially toxic effects of AgNP at the intestinal level.


1998 ◽  
Vol 94 (4) ◽  
pp. 359-365 ◽  
Author(s):  
Michael Kaiser ◽  
Ole Kahr ◽  
Yasuyuki Shimada ◽  
Pamela Smith ◽  
Martin Kelly ◽  
...  

1. Adrenomedullin is a recently discovered vasodilating and natriuretic peptide whose physiological and pathophysiological roles remain to be established. Like atrial natiuretic peptide adrenomedullin is expressed in the left ventricle. Ventricular expression of atrial natriuretic peptide is known to be markedly increased by volume or pressure overload. In this study we investigated whether ventricular expression of adrenomedullin is similarly stimulated under such conditions. 2. Ventricular adrenomedullin and atrial natriuretic peptide mRNA levels as well as those of a loading control mRNA (glyceraldehyde-3-phosphate dehydrogenase) were quantified by Northern blot analysis in (a) rats with severe post-infarction heart failure induced by left coronary ligation at 30 days post-surgery and (b) in rats with pressure-related cardiac hypertrophy induced by aortic banding at several time points (0.5, 1 and 4 h, and 1, 4, 7 and 28 days) after surgery. Levels were compared with those in matched sham-operated controls. 3. The mRNA level of atrial natriuretic peptide was markedly increased (8–10-fold) in the left ventricle of animals with post-infarction heart failure. In contrast, there was only a modest (40%) increase in the level of adrenomedullin mRNA. In rats with pressure-induced cardiac hypertrophy the ventricular level of atrial natriuretic peptide mRNA was again markedly increased (maximum 10-fold). The increase was first noticeable at 24 h post-banding and persisted until 28 days. In contrast, there was no change in adrenomedullin mRNA level compared with sham-operated rats at any time point. 4. Despite having similar systemic effects, the expression of adrenomedullin and atrial natriuretic peptide in the left ventricle is differently regulated. The findings imply distinct roles for the two peptides. The results do not support an important role for ventricular adrenomedullin expression in the remodelling process that occurs during the development of cardiac hypertrophy but suggest that ventricular adrenomedullin participates in the local and/or systemic response to heart failure


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Attila Bebes ◽  
Ferenc Kovács-Sólyom ◽  
Judit Prihoda ◽  
Róbert Kui ◽  
Lajos Kemény ◽  
...  

This study was carried out to examine the possible role of interleukin-1 (IL-1) in the functional insufficiency of regulatory T cells in psoriasis, by comparing the expression of IL-1 receptors on healthy control and psoriatic T cells. Patients with moderate-to-severe chronic plaque psoriasis and healthy volunteers, matched in age and sex, were selected for all experiments. CD4+CD25−effector and CD4+CD25+CD127lowregulatory T cells were separated and used for the experiments. Expression of the mRNA of IL-1 receptors (IL-1R1, IL-1R2, and sIL-1R2) was determined by quantitative real-time RT-PCR. Cell surface IL-1 receptor expression was assessed by flow cytometry. Relative expression of the signal transmitting IL-1 receptor type 1 (IL-1R1) mRNA is higher in resting psoriatic effector and regulatory T cells, and activation induces higher IL-1R1 protein expression in psoriatic T cells than in healthy cells. Psoriatic regulatory and effector T cells express increased mRNA levels of the decoy IL-1 receptors (IL-1R2 and sIL-1R2) upon activation compared to healthy counterparts. Psoriatic T cells release slightly more sIL-1R2 into their surrounding than healthy T cells. In conclusion, changes in the expression of IL-1 receptors in psoriatic regulatory and effector T cells could contribute to the pathogenesis of psoriasis.


2014 ◽  
Vol 41 (5) ◽  
pp. 945-954 ◽  
Author(s):  
Zvezdana Mladenovic ◽  
Anne-Sophie Saurel ◽  
Francis Berenbaum ◽  
Claire Jacques

Objective.To determine the effect of hyaluronic acid (HA) on proteolytic enzymes and bone remodeling mediators induced by interleukin 1β (IL-1β) and related to cartilage catabolism in murine osteoblasts.Methods.Osteoblasts were obtained from Swiss mice and cultured for 3 weeks. HA-treated osteoblasts were incubated with 100 μg/ml HA during the last week of culture, then stimulated with IL-1β (10 ng/ml) for 24 h. The expression of matrix metalloproteinases 3 and 13 (MMP-3 and MMP-13), ADAMTS-4 and ADAMTS-5, tissue inhibitor of metalloproteinases (TIMP), osteoprotegerin, and receptor activator of nuclear factor-κB ligand (RANKL) was determined by real-time polymerase chain reaction. MMP-3 and MMP-13 release was assessed by Western blot analysis.Results.IL-1β increased the mRNA levels of MMP-3 and MMP-13 and ADAMTS-4 and ADAMTS-5 and release of MMP-3 and MMP-13. Seven days of HA treatment significantly prevented the IL-1β-increased mRNA levels of MMP-3 (−61%, p < 0.01), MMP-13 (−56%, p < 0.01), ADAMTS-4 (−58%, p < 0.05), ADAMTS-5 (−52%, p < 0.01), and RANKL (−49%, p < 0.05), but not TIMP. As well, IL-1β-induced production of MMP-3 and MMP-13 was inhibited, by 27% (p < 0.01) and 40% (p < 0.01), respectively.Conclusion.In an inflammatory context in murine osteoblasts, HA can inhibit the expression of MMP and ADAMTS. Because HA can counteract the production of these mediators in chondrocytes, its beneficial effect in osteoarthritis may be due to its action on cartilage and subchondral bone.


1995 ◽  
Vol 310 (1) ◽  
pp. 143-148 ◽  
Author(s):  
D Zhang ◽  
S L Jiang ◽  
D Rzewnicki ◽  
D Samols ◽  
I Kushner

The combination of interleukin 6 (IL-6) and interleukin 1 (IL-1) synergistically induces the human acute-phase reactant, C-reactive protein (CRP) in Hep3B cells. While previous studies have indicated that IL-6 induces transcription of CRP, the mode of action of IL-1 has not been clearly defined. It has been suggested that the effect of IL-1 might be post-transcriptional, exerted through the 5′-untranslated region (5′-UTR). To evaluate the role of IL-1 in CRP gene expression, we studied the effects of interleukin-6 (IL-6) and interleukin-1 beta (IL-1 beta) on both the endogenous CRP gene and on transfected CRP-CAT constructs in Hep3B cells. In kinetic studies of the endogenous CRP gene, IL-1 beta alone had no effect on CRP mRNA levels, but when added to IL-6, synergistically enhanced both CRP mRNA levels and transcription, as determined by Northern-blot analyses and nuclear run-on studies. IL-6 alone and the combination of [IL-1 beta + IL-6] each induced increases in mRNA levels roughly comparable with observed increases in transcription. These findings indicate that the effect of IL-1 beta on CRP expression is exerted largely at the transcriptional level in this system. This conclusion was confirmed by studies in Hep3B cells transiently transfected with CRP-CAT constructs, each containing 157 bp of the CRP 5′-flanking region but differing in the length of the 5′-UTR from 104 bp to 3 bp. All constructs responded in the same way; IL-6, but not IL-1 beta, induced significant chloramphenicol acetyltransferase (CAT) expression which was synergistically enhanced 2- to 3-fold by IL-1 beta. These results indicate that IL-1 beta stimulates transcriptional events in the presence of IL-6 and that the upstream 157 bases of the CRP promoter contain elements capable of both IL-6 induction and the synergistic effect of IL-1 beta on transcription.


2013 ◽  
Vol 3 (2) ◽  
pp. 89-95 ◽  
Author(s):  
Ehab Tousson ◽  
Ezar Hafez ◽  
Ahmed A. Massoud ◽  
Osama Sweef ◽  
Nermin Atta

Cancers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 355 ◽  
Author(s):  
Valerio Gelfo ◽  
Martina Mazzeschi ◽  
Giada Grilli ◽  
Moshit Lindzen ◽  
Spartaco Santi ◽  
...  

Cetuximab (CTX) is a monoclonal antibody targeting the epidermal growth factor receptor (EGFR), commonly used to treat patients with metastatic colorectal cancer (mCRC). Unfortunately, objective remissions occur only in a minority of patients and are of short duration, with a population of cells surviving the treatment and eventually enabling CTX resistance. Our previous study on CRC xenopatients associated poor response to CTX with increased abundance of a set of pro-inflammatory cytokines, including the interleukins IL-1A, IL-1B and IL-8. Stemming from these observations, our current work aimed to assess the role of IL-1 pathway activity in CTX resistance. We employed a recombinant decoy TRAP IL-1, a soluble protein combining the human immunoglobulin Fc portion linked to the extracellular region of the IL-1-receptor (IL-1R1), able to sequester IL-1 directly from the medium. We generated stable clones expressing and secreting a functional TRAP IL-1 into the culture medium. Our results show that IL-1R1 inhibition leads to a decreased cell proliferation and a dampened MAPK and AKT axes. Moreover, CRC patients not responding to CTX blockage displayed higher levels of IL-1R1 than responsive subjects, and abundant IL-1R1 is predictive of survival in patient datasets specifically for the consensus molecular subtype 1 (CMS1). We conclude that IL-1R1 abundance may represent a therapeutic marker for patients who become refractory to monoclonal antibody therapy, while inhibition of IL-1R1 by TRAP IL-1 may offer a novel therapeutic strategy.


2021 ◽  
Author(s):  
Arubala P Reddy ◽  
Xiangling Yin ◽  
Neha Sawant ◽  
P Hemachandra Reddy

Abstract The purpose of this study is to study the neuroprotective role of selective serotonin reuptake inhibitor (SSRI), citalopram against Alzheimer’s disease (ad). Multiple SSRIs, including citalopram are reported to treat patients with depression, anxiety, and ad. However, their protective cellular mechanisms have not been studied completely. In the current study, we investigated the protective role of citalopram against impaired mitochondrial dynamics, defective mitochondrial biogenesis, defective mitophagy, and synaptic dysfunction in immortalized mouse primary hippocampal cells (HT22) expressing mutant APP (SWI/IND) mutations. Using quantitative RT-PCR, immunoblotting, biochemical methods and transmission electron microscopy methods, we assessed mutant full-length APP/C-terminal fragments and Aβ levels and mRNA and protein levels of mitochondrial dynamics, biogenesis, mitophagy, and synaptic genes in mAPP-HT22 cells and mAPP-HT22 cells treated with citalopram. Increased levels of mRNA levels of mitochondrial fission genes, decreased levels of fusion biogenesis, autophagy, mitophagy and synaptic genes were found in mAPP-HT22 cells relative to WT-HT22 cells. However, in mAPP-HT22 cells treated with citalopram compared to mAPP-HT22 cells, revealed reduced levels of the mitochondrial fission genes, increased fusion, biogenesis, autophagy, mitophagy, and synaptic genes. Our protein data agrees with mRNA levels. Transmission electron microscopy revealed significantly increased mitochondrial numbers and reduced mitochondrial length in mAPP-HT22 cells; these were reversed in citalopram treated mAPP-HT22 cells. Cell survival rates were increased in citalopram treated mAPP-HT22 relative to citalopram-untreated mAPP-HT22. Further, mAPP and C-terminal fragments were also reduced in citalopram treated cells. These findings suggest that citalopram reduces mutant APP and Aβ and mitochondrial toxicities and may have a protective role of mutant APP and Aβ-induced injuries in patients with depression, anxiety, and ad.


2017 ◽  
Vol 34 (02) ◽  
pp. 058-067
Author(s):  
A. Sadek ◽  
R. Khattab ◽  
A. Amer ◽  
A. Youssef

Abstract Introduction: Prolonged breathing of high oxygen concentration leads to hyperoxic acute lung injury. Neonatal Respiratory diseases usually require increased supplement of high oxygen concentrations, so neonates are more susceptible to hyperoxic acute lung injury. The aim of this work was to investigate the protective role of caffeine versus N-acetylcysteine against hyperoxic acute lung injury in neonatal rats. Materials and Methods: 32 albino rats aged seven days were used in this experiment. The pups were divided into four groups; 1) Control or normoxic group; rats placed in normoxic chamber where fraction of inspired oxygen (FiO2) was 0.21, 2) Hyperoxic group; rats were placed in hyperoxic chamber (FiO2>0.8) using an oxygen flow of 1.5 Litre/min, 3) Hyperoxia-CAF group; rats exposed to hyperoxia and received a single intra-peritoneal injection of 20 mg/kg caffeine just prior to exposure, and 4) Hyperoxia-NAC group; rats exposed to hyperoxia and received a single intra-peritoneal injection of 150 mg/kg N-acetylcysteine just prior to exposure. 48 hours after exposure, lung specimens were processed for histological and immunohistochemical study using caspase-3, cluster of differentiation-68-antibody (CD68) and interleukin-1-beta (IL-1β). Results: Neonatal hyperoxia led to severe impairment in lung architecture, with a highly significant increase in alveolar macrophages. Also, caspase and IL-1β immune-reaction were increased significantly as compared to control group. Caffeine could improve the histolopathological picture of hyperoxic acute lung injury, and also could decrease alveolar macrophage count and IL-1β immune-reaction better than N-acetylcysteine. Conclusion: Caffeine is more effective than N-acetylcysteine in prophylaxis against hyperoxic acute lung injury in neonates.


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