Induction of HSP 32 gene in hypoxic cardiomyocytes  is attenuated by treatment withN-acetyl-l-cysteine

Increased synthesis of stress proteins may enhance myocardial viability during periods of low oxygen delivery. Our purpose was to determine if the oxidative stress protein heme oxygenase-1 [heat stress protein 32 (HSP 32)] was induced in hypoxic cardiomyocytes and whether this induction might be mediated by a redox-sensitive mechanism. Primary rat neonatal cardiomyocytes, cultured to express a tissuelike phenotype, responded to 12 h of hypoxia (<0.5% ambient oxygen) with an approximately fivefold (range 3- to 7.5-fold; P < 0.05) increase in HSP 32 mRNA and a threefold ( P < 0.05) increase in HSP 32 protein content. Exposure to 80 μM H2O2for 3 h increased HSP 32 mRNA content to a similar extent. Expression of heme oxygenase-2 mRNA was unaffected by H2O2or hypoxic treatments. Inclusion of 20 mM N-acetyl-l-cysteine in the medium during hypoxia reduced the increase in HSP 32 mRNA and protein expression by 25–50% compared with hypoxia alone. The data suggest that induction of HSP 32 protein may lead to an improved antioxidant defense in cardiomyocytes during hypoxia and that a redox-sensitive pathway mediates at least a portion of the hypoxic induction of the HSP 32gene.

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Ozonation of Human Blood Induces a Remarkable Upregulation of Heme Oxygenase-1 and Heat Stress Protein-70

Mediators of Inflammation ◽

10.1155/2007/26785 ◽

2007 ◽

Vol 2007 ◽

pp. 1-6 ◽

Cited By ~ 23

Author(s):

Velio Bocci ◽

Carlo Aldinucci ◽

Francesca Mosci ◽

Fabio Carraro ◽

Giuseppe Valacchi

Keyword(s):

Human Plasma ◽

Heme Oxygenase ◽

Vascular Endothelial Cells ◽

Stress Protein ◽

Heme Oxygenase 1 ◽

Immune Reactivity ◽

Vascular Endothelial ◽

Hsp 70 ◽

Heat Stress Protein ◽

Dose Dependent

Heme oxygenase-I (HO-1) has emerged as one of the most protective enzymes and its pleiotropic activities have been demonstrated in a variety of human pathologies. Unpublished observations have shown that HO-1 is induced after the infusion of ozonated blood into the respective donors, and many other experimental observations have demonstrated the efficacy of oxidizing agents. It appeared worthwhile to evaluate whether we could better define the activity of potential inducers such as hydrogen peroxide and ozonated human plasma. Human vascular endothelial cells at confluence were challenged with different concentrations of these inducers and the simultaneous production of nitric oxide (NO); and HO-1 was measured by either measuring nitrite, or bilirubin formation, or/and the immune reactivity of the protein by Western blot using a rabbit antihuman HO-1 and Hsp-70. The results show that production of both NO and HO-1 is fairly dose dependent but is particularly elevated using human plasma after transient exposure to a medium ozone concentration. At this concentration, there is also induction of Hsp-70. The results clarify another positive effect achievable by the use of ozone therapy.

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A Universal Stress Protein upregulated by hypoxia may contribute to chronic lung colonisation and intramacrophage survival in cystic fibrosis

10.1101/2020.10.03.324806 ◽

2020 ◽

Author(s):

Andrew O’Connor ◽

Rita Berisio ◽

Mary Lucey ◽

Kirsten Schaffer ◽

Siobhán McClean

Keyword(s):

Oxidative Stress ◽

Chronic Infection ◽

Stress Proteins ◽

Cell Attachment ◽

Stress Protein ◽

Acid Stress ◽

Nutrient Deficiency ◽

Fold Increase ◽

Burkholderia Cenocepacia ◽

Low Oxygen

SummaryUniversal stress proteins (USPs) are ubiquitously expressed in bacteria, plants and eukaryotes and play a lead role in adaptation to environmental conditions. In Gram negative bacteria they enable adaption of bacterial pathogens to the conditions encountered in the human niche, including hypoxia, oxidative stress, osmotic stress, nutrient deficiency or acid stress, thereby facilitating colonisation. We previously reported that all six USP proteins encoded within a low-oxygen responsive locus in Burkholderia cenocepacia showed increased abundance during chronic colonisation of the CF lung. However, the role of USPs in chronic infection is not known. Using mutants derived from B. cenocepacia strain, K56-2, we show that USP76 is required for growth and survival in many conditions associated with the CF lung including, hypoxia, acidic conditions, oxidative stress. Moreover, it is involved in attachment to host epithelial cells, but not virulence. It also has a role in survival in macrophages isolated from people with CF. In contrast, another USP encoded in the same locus, USP92 had no effect on host cell attachment or oxidative stress, but was responsible for a 3-fold increase in virulence. Overall this shows that these USPs, both upregulated during chronic infection, have distinct roles in Burkholderia pathogenesis and may support the survival of B. cenocepacia in the CF lung. Specifically, USP76 is involved in its survival within CF macrophages, a hallmark of Burkholderia infection.

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Heme oxygenase-1 mediates the anti-inflammatory actions of 2′-hydroxychalcone in RAW 264.7 murine macrophages

AJP Cell Physiology ◽

10.1152/ajpcell.00380.2005 ◽

2006 ◽

Vol 290 (4) ◽

pp. C1092-C1099 ◽

Cited By ~ 62

Author(s):

Hadil Abuarqoub ◽

Roberta Foresti ◽

Colin J. Green ◽

Roberto Motterlini

Keyword(s):

Heme Oxygenase ◽

Stress Protein ◽

Protoporphyrin Ix ◽

Heme Oxygenase 1 ◽

Raw 264.7 ◽

Oxygenase Activity ◽

Tnf Α ◽

Anti Inflammatory ◽

Oxide Synthase ◽

Interfering Rna

Chalcones are a group of plant-derived polyphenolic compounds that belong to the flavonoids family, and possess a wide variety of cytoprotective and modulatory functions. Chalcones exert their cytoprotective actions via activation of specific transcriptional factors and upregulation of endogenous defensive pathways, such as phase II enzymes and the stress protein heme oxygenase-1 (HO-1). In this study, we investigated the anti-inflammatory action of 2′-hydroxychalcone (2-HC) in a model of lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and examined the role of HO-1 in this process. Our results demonstrate that 2-HC potently induces HO-1 expression and markedly reduces LPS-mediated nitrite and TNF-α production. These effects are accompanied by inhibition of inducible nitric oxide synthase protein expression and abolished by blockade of heme oxygenase activity with either tin protoporphyrin IX or HO-1 small interfering RNA. By using a pharmacological approach and siRNA technology, we also found that phosphatidylinositol 3-kinase is a major cellular mediator in 2-HC-induced HO-1 expression. These findings strongly suggest that 2-HC exerts anti-inflammatory actions via activation of the HO-1 pathway and help to elucidate the mechanisms underlying the potential therapeutic value of chalcones.

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Specific induction of the 70-kD heat stress proteins by the tyrosine kinase inhibitor herbimycin-A protects rat neonatal cardiomyocytes. A new pharmacological route to stress protein expression?

Journal of Clinical Investigation ◽

10.1172/jci118468 ◽

1996 ◽

Vol 97 (3) ◽

pp. 706-712 ◽

Cited By ~ 67

Author(s):

S D Morris ◽

D V Cumming ◽

D S Latchman ◽

D M Yellon

Keyword(s):

Heat Stress ◽

Protein Expression ◽

Tyrosine Kinase Inhibitor ◽

Stress Proteins ◽

Kinase Inhibitor ◽

Stress Protein ◽

Neonatal Cardiomyocytes ◽

Herbimycin A ◽

Specific Induction ◽

Heat Stress Proteins

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Expression of ACE2 in the Intact and Acutely Injured Kidney

Kidney360 ◽

10.34067/kid.0001562021 ◽

2021 ◽

pp. 10.34067/KID.0001562021

Author(s):

Karl A. Nath ◽

Raman Deep Singh ◽

Joseph P. Grande ◽

Vesna D. Garovic ◽

Anthony J. Croatt ◽

...

Keyword(s):

Protein Expression ◽

Mrna Expression ◽

Heme Oxygenase ◽

Urinary Tract Obstruction ◽

Kidney Injury ◽

Heme Oxygenase 1 ◽

Renal Tubular Epithelium ◽

Mrna And Protein Expression ◽

Intact Kidney ◽

Renal Tubular

Background. The actions of angiotensin-converting enzyme 2 (ACE2) oppose those of the renin-angiotensin-aldosterone system. Evidence supports ACE2 as a cytoprotectant in some tissues. This study examined ACE2 expression in models of acute kidney injury (AKI). Methods. ACE2 mRNA and protein expression, ACE2 activity, and ACE2 expression by immunofluorescence were assessed following ischemic AKI in mice. Renal ACE2 mRNA expression was evaluated in lipopolysaccharide-induced AKI in wildtype (C57BL/6J) mice, in heme oxygenase-1+/+ and heme oxygenase-1-/- mice, and following unilateral urinary tract obstruction (UUO) in wildtype mice. The effect of sex and age on renal ACE2 protein expression was also assessed. Results. In ischemic AKI, ACE2 mRNA and protein expression and ACE2 activity were reduced as compared with such indices in the intact kidney. In ischemic AKI, ACE2, which, in health, is prominently expressed in the renal tubular epithelium, especially in proximal tubules, exhibited decreased expression in these segments. Decreased ACE2 expression in AKI did not reflect reduced GFR per se as ACE2 mRNA expression was unaltered after UUO. Lipopolysaccharide induced renal ACE2 mRNA expression in wildtype mice, but this effect of lipopolysaccharide did not occur in heme oxygenase-1 deficient mice. In the intact kidney, renal ACE2 protein expression decreased in female mice as compared with male mice, but was unaltered with age. Conclusion. We conclude that renal ACE2 expression is decreased in ischemic AKI, one characterized by markedly reduced GFR and abundant cell death, but is upregulated in lipopolysaccharide-induced AKI; this latter effect requires heme oxygenase-1. Determining the significance of ACE2 expression in models of AKI merits further study. We also suggest that understanding the mechanism underlying ACE2 downregulation in AKI may offer insights relevant to COVID-19: ACE2 is downregulated after ACE2 mediates SARS-CoV-2 cellular entry; such downregulation promotes inflammation in COVID-19; and AKI commonly occurs and determines outcomes in COVID-19.

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Role of heme oxygenase-1 in hypoxia-reoxygenation: requirement of substrate heme to promote cardioprotection

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.281.5.h1976 ◽

2001 ◽

Vol 281 (5) ◽

pp. H1976-H1984 ◽

Cited By ~ 66

Author(s):

Roberta Foresti ◽

Helen Goatly ◽

Colin J. Green ◽

Roberto Motterlini

Keyword(s):

Heme Oxygenase ◽

Reactive Oxygen Species Generation ◽

Free Radical Scavenger ◽

Radical Scavenger ◽

Heme Oxygenase 1 ◽

Bile Pigment ◽

Activity Levels ◽

Low Oxygen ◽

Heme Oxygenase Activity ◽

Oxygenase Activity

Heme oxygenase-1 (HO-1) catalyzes the enzymatic degradation of heme to carbon monoxide, bilirubin, and iron. All three products possess biological functions; bilirubin, in particular, is a potent free radical scavenger of which its antioxidant property is enhanced at low oxygen tension. Here, we investigated the effect of severe hypoxia and reoxygenation on HO-1 expression in cardiomyocytes and determined whether HO-1 and its product, bilirubin, have a protective role against reoxygenation damage. Hypoxia caused a time-dependent increase in both HO-1 expression and heme oxygenase activity, which gradually declined during reoxygenation. Reoxygenation of hypoxic cardiomyocytes produced marked injury; however, incubation with hemin or bilirubin during hypoxia considerably reduced the damage at reoxygenation. The protective effect of hemin is attributable to increased availability of substrate for heme oxygenase activity, because hypoxic cardiomyocytes generated very little bilirubin when incubated with medium alone but produced substantial bile pigment in the presence of hemin. Interestingly, incubation with hemin also maintained high heme oxygenase activity levels during the reoxygenation period. Reactive oxygen species generation was enhanced after hypoxia, and hemin and bilirubin were capable once again to attenuate this effect. These results indicate that the HO-1-bilirubin pathway can effectively defend hypoxic cardiomyocytes against reoxygenation injury and highlight the issue of heme availability in the cytoprotective action afforded by HO-1.

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Induction of heme oxygenase-1 (HSP32) mRNA in skeletal muscle following contractions

AJP Cell Physiology ◽

10.1152/ajpcell.1997.272.1.c59 ◽

1997 ◽

Vol 272 (1) ◽

pp. C59-C67 ◽

Cited By ~ 54

Author(s):

D. A. Essig ◽

D. R. Borger ◽

D. A. Jackson

Keyword(s):

Oxidative Stress ◽

Stress Proteins ◽

Stress Protein ◽

Polymerase Chain Reaction Analysis ◽

Relative Increase ◽

Muscle Contractions ◽

Heme Oxygenase 1 ◽

Control Value ◽

Actin Mrna ◽

Heat Stress Proteins

The capacity of preexisting antioxidant pathways to handle oxidative stress during exercise may be complemented by the synthesis of inducible heat stress proteins (HSP). Our purpose was to determine if the amount of mRNA for HSP32, a major oxidative stress protein, was increased in muscle after repetitive contractions. Reverse transcriptase-polymerase chain reaction analysis showed that HSP32 mRNA (normalized to alpha-actin mRNA) was increased about seven- and about fourfold (P < 0.35) immediately after 1 h of exhaustive running and after 3 h of muscle contractions (10 Hz nerve stimulation), respectively. Northern blot analysis revealed that HSP70 mRNAs were 3.5- to 15.5-fold above control value (P < 0.05), whereas the content of another oxidative stress protein mRNA (macrophage stress protein 23) was unchanged 0 h after contractions. The relative increase in HSP32 mRNA was found to be dependent on active tension generation; passive tension did not increase the HSP32-to-actin mRNA ratio. Increases in HSP32 mRNA may underlie an inducible antioxidant pathway in muscle responsive to metabolic stresses associated with repeated muscle contractions.

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