scholarly journals Competitive HIF Prolyl Hydroxylase Inhibitors Show Protection against Oxidative Stress by a Mechanism Partially Dependent on Glycolysis

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ann-Louise Bergström ◽  
Karina Fog ◽  
Thomas Nikolaj Sager ◽  
Anne Techau Bruun ◽  
Kenneth Thirstrup
Keyword(s):  
Oxidative Stress ◽  
Hypoxia Inducible Factor ◽  
Large Degree ◽  
Cell Types ◽  
Prolyl Hydroxylase ◽  
Adaptation To Hypoxia ◽  
Cellular Effects ◽  
Competitive Inhibitors ◽  
Inhibitor Compounds ◽  
Hif Prolyl Hydroxylase

The hypoxia inducible factor 1 (HIF-1) is a central transcription factor involved in the cellular and molecular adaptation to hypoxia and low glucose supply. The level of HIF-1 is to a large degree regulated by the HIF prolyl hydroxylase enzymes (HPHs) belonging to the Fe(II) and 2-oxoglutarate-dependent dioxygenase superfamily. In the present study, we compared competitive and noncompetitive HPH-inhibitor compounds in two different cell types (SH-SY5Y and PC12). Although the competitive HPH-inhibitor compounds were found to be pharmacologically more potent than the non-competitive compounds at inhibiting HPH2 and HPH1, this was not translated into the cellular effects of the compounds, where the non-competitive inhibitors were actually more potent than the competitive in stabilizing and translocatingHIF1αto the nucleus (quantified with Cellomics ArrayScan technology). This could be explained by the high cellular concentrations of the cofactor 2-oxoglutarate (2-OG) as the competitive inhibitors act by binding to the 2-OG site of the HPH enzymes. Both competitive and non-competitive HPH inhibitors protected the cells against 6-OHDA induced oxidative stress. In addition, the protective effect of a specific HPH inhibitor was partially preserved when the cells were serum starved and exposed to 2-deoxyglucose, an inhibitor of glycolysis, indicating that other processes than restoring energy supply could be important for the HIF-mediated cytoprotection.

scholarly journals The pro-oncogenic adaptor CIN85 inhibits hypoxia-inducible factor prolyl hydroxylase-2

2018 ◽  
Author(s):  
Nina Kozlova ◽  
Daniela Mennerich ◽  
Anatoly Samoylenko ◽  
Elitsa Y. Dimova ◽  
Peppi Koivunen ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Survival Function ◽  
Hypoxia Inducible Factor ◽  
Adaptor Protein ◽  
Prolyl Hydroxylase ◽  
Binding Partner ◽  
And Migration ◽  
Hif Prolyl Hydroxylase ◽  
Promote Breast Cancer

SummaryThe EGFR-adaptor protein CIN85 has been shown to promote breast cancer malignancy and hypoxia-inducible factor (HIF) stability. However, the mechanisms underlying cancer promotion remain ill-defined. Here, we show that CIN85 is a novel binding partner of the main HIF-prolyl hydroxylase PHD2, but not of PHD1 or PHD3. Mechanistically, the N-terminal SH3 domains of CIN85 interact with the proline-arginine rich region within the N-terminus of PHD2, thereby inhibiting PHD2 activity and HIF-degradation. This activity is essential in vivo, as specific loss of the CIN85-PHD2 interaction in CRISPR/Cas9 edited cells affected growth and migration properties as well as tumor growth in mice. Overall, we discovered a previously unrecognized tumor growth checkpoint that is regulated by CIN85-PHD2, and uncovered an essential survival function in tumor cells linking growth factor adaptors with hypoxia signaling.

scholarly journals Carcinogenicity Assessment of Daprodustat (GSK1278863), a Hypoxia-Inducible Factor (HIF)-Prolyl Hydroxylase Inhibitor

2019 ◽  
Vol 48 (2) ◽  
pp. 362-378 ◽  
Author(s):  
David F. Adams ◽  
Mark S. Watkins ◽  
Luc Durette ◽  
Josée Laliberté ◽  
Félix Goulet ◽  
...  
Keyword(s):  
Cell Mass ◽  
Hypoxia Inducible Factor ◽  
Carcinogenic Risk ◽  
Prolyl Hydroxylase ◽  
High Dose ◽  
Sprague Dawley ◽  
Time Curve ◽  
Clinical Exposure ◽  
High Doses ◽  
Hif Prolyl Hydroxylase

Daprodustat (GSK1278863) is a hypoxia-inducible factor (HIF)-prolyl hydroxylase (PHD) inhibitor in development for treatment of anemia of chronic kidney disease. Daprodustat’s biological activity simulates components of the natural response to hypoxia; inhibition of PHDs results in HIF stabilization and modulation of HIF-controlled gene products, including erythropoietin. The carcinogenic potential of daprodustat was evaluated in 2-year carcinogenicity studies in Sprague-Dawley rats and CD-1 mice, where once-daily doses were administered. The mouse study also included evaluation of daprodustat’s 3 major circulating human metabolites. There were no neoplastic findings that were considered treatment related in either study. Exaggerated pharmacology resulted in significantly increased red cell mass and subsequent multiorgan congestion and secondary non-neoplastic effects in both species, similar to those observed in chronic toxicity studies. In rats, these included aortic thrombosis and an exacerbation of spontaneous rodent cardiomyopathy, which contributed to a statistically significant decrease in survival in high-dose males (group terminated in week 94). Survival was not impacted in mice at any dose. Systemic exposures (area under the plasma concentration–time curve) to daprodustat at the high doses in rats and mice exceed predicted maximal human clinical exposure by ≥143-fold. These results suggest that daprodustat and metabolites do not pose a carcinogenic risk at clinical doses.

scholarly journals Molecular Assessment of Epiretinal Membrane: Activated Microglia, Oxidative Stress and Inflammation

Antioxidants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 654 ◽  
Author(s):  
Sushma Vishwakarma ◽  
Rishikesh Kumar Gupta ◽  
Saumya Jakati ◽  
Mudit Tyagi ◽  
Rajeev Reddy Pappuru ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Epiretinal Membrane ◽  
Hypoxia Inducible Factor ◽  
Gene Expression Signature ◽  
Cell Types ◽  
Activated Microglia ◽  
Inflammatory Conditions ◽  
New Information ◽  
And Function

Fibrocellular membrane or epiretinal membrane (ERM) forms on the surface of the inner limiting membrane (ILM) in the inner retina and alters the structure and function of the retina. ERM formation is frequently observed in ocular inflammatory conditions, such as proliferative diabetic retinopathy (PDR) and retinal detachment (RD). Although peeling of the ERM is used as a surgical intervention, it can inadvertently distort the retina. Our goal is to design alternative strategies to tackle ERMs. As a first step, we sought to determine the composition of the ERMs by identifying the constituent cell-types and gene expression signature in patient samples. Using ultrastructural microscopy and immunofluorescence analyses, we found activated microglia, astrocytes, and Müller glia in the ERMs from PDR and RD patients. Moreover, oxidative stress and inflammation associated gene expression was significantly higher in the RD and PDR membranes as compared to the macular hole samples, which are not associated with inflammation. We specifically detected differential expression of hypoxia inducible factor 1-α (HIF1-α), proinflammatory cytokines, and Notch, Wnt, and ERK signaling pathway-associated genes in the RD and PDR samples. Taken together, our results provide new information to potentially develop methods to tackle ERM formation.

scholarly journals Hypoxia-inducible factor (HIF)-prolyl hydroxylase 3 (PHD3) maintains high HIF2A mRNA levels in clear cell renal cell carcinoma

2019 ◽  
Vol 294 (10) ◽  
pp. 3760-3771 ◽  
Author(s):  
Petra Miikkulainen ◽  
Heidi Högel ◽  
Fatemeh Seyednasrollah ◽  
Krista Rantanen ◽  
Laura L. Elo ◽  
...  
Keyword(s):  
Renal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Renal Cell ◽  
Clear Cell ◽  
Hypoxia Inducible Factor ◽  
Prolyl Hydroxylase ◽  
Mrna Levels ◽  
Cell Renal Cell Carcinoma ◽  
Hif Prolyl Hydroxylase

scholarly journals Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibition: Robust New Target or Another Big Bust for Stroke Therapeutics?

2012 ◽  
Vol 32 (7) ◽  
pp. 1347-1361 ◽  
Author(s):  
Saravanan S Karuppagounder ◽  
Rajiv R Ratan
Keyword(s):  
Oxidative Stress ◽  
Functional Outcomes ◽  
Hemorrhagic Stroke ◽  
Hypoxia Inducible Factor ◽  
Iron Chelators ◽  
Adaptation To Hypoxia ◽  
Prolyl Hydroxylases ◽  
Stroke Models ◽  
Transcriptional Adaptation ◽  
Compensatory Programs

A major challenge in developing stroke therapeutics that augment adaptive pathways to stress has been to identify targets that can activate compensatory programs without inducing or adding to the stress of injury. In this regard, hypoxia-inducible factor prolyl hydroxylases (HIF PHDs) are central gatekeepers of posttranscriptional and transcriptional adaptation to hypoxia, oxidative stress, and excitotoxicity. Indeed, some of the known salutary effects of putative ‘antioxidant’ iron chelators in ischemic and hemorrhagic stroke may derive from their abilities to inhibit this family of iron, 2-oxoglutarate, and oxygen-dependent enzymes. Evidence from a number of laboratories supports the notion that HIF PHD inhibition can improve histological and functional outcomes in ischemic and hemorrhagic stroke models. In this review, we discuss this evidence and highlight important gaps in our understanding that render HIF PHD inhibition a promising but not yet preclinically validated target for protection and repair after stroke.

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