Hypoxia-inducible Factor Signaling Research Articles

The role of hypoxia-inducible factors 1 and 2 in the pathogenesis of diabetic kidney disease

AbstractAccording to the 10th edition of the IDF Diabetes Atlas, 537 million people suffered from diabetes in 2021, and this number will increase by 47% by 2045. It is estimated that even 30–40% of these individuals may develop diabetic kidney disease (DKD) in the course of diabetes. DKD is one of the most important complications of diabetes, both in terms of impact and magnitude. It leads to high morbidity and mortality, which subsequently impacts on quality of life, and it carries a high financial burden. Diabetic kidney disease is considered a complex and heterogeneous entity involving disturbances in vascular, glomerular, podocyte, and tubular function. It would appear that hypoxia-inducible factors (HIF)-1 and HIF-2 may be important players in the pathogenesis of this disease. However, their exact role is still not fully investigated. In this article, we summarize the current knowledge about HIF signaling and its role in DKD. In addition, we focus on the possible effects of nephroprotective drugs on HIF expression and activity in various tissues. Graphical abstract

Altered hypoxia- and redox-related transcriptional signatures in mitochondrial-DNA-depleted PC-3 cells

Rho 0 (ρ0) cells are widely used as a tool to investigate how the absence of respiring mitochondria affects a variety of physiological and pathological processes. Prominently, ρ0 cells have been used to study the role of mitochondrial reactive oxygen species (ROS) production and/or mitochondrial respiration in the stabilization of the hypoxia-inducible factor (HIF) in hypoxia. In this study, we cultured ρ0 and WT PC-3 cells in 5% O2 (physioxia) and Plasmax medium for 2 weeks prior to transcriptomic and functional analyses. RNA-seq showed that ρ0 PC-3 cells exhibit impaired induction of HIF-regulated genes when exposed to hypoxia, compared to wild-type (WT) cells. Surprisingly, when comparing the transcriptomes of ρ0 and WT cells in physioxia (5% O2), we found a strong presence of HIF-related gene signatures in ρ0 cells compared to WT. Among the HIF targets found to be upregulated in ρ0 cells are CA9, EGLN3, EPAS1, HK2, ENO2, and SLC2A1. Moreover, several Nrf2 targets were upregulated in ρ0 cells, including NQO1, HMOX1, GPX2, and SLC7A11, which is in line with ρ0 cells showing a significantly higher H2O2 efflux rate than WT cells. Given the alterations in HIF-dependent and Nrf2-dependent gene expression and basal ROS production observed in ρ0 PC-3 cells, we conclude that caution should be taken when interpreting the results from experiments that focus on ROS production and HIF signaling using ρ0 cells as a model.

Role of Protein Ubiquitination and HIF Signaling in the Evolution of Hypoxic Breast Cancer.

Alternations in protein ubiquitination along with hypoxia-inducible factor (HIF) signaling contribute to tumorigenesis and breast tumor advancement. Ubiquitination is an impulsive process, which is coordinately governed by E3 ligases and deubiquitinases (DUBs), that have come out as charismatic therapeutic targets. HIF expression, as well as the transcriptional process in malignancies, are frequently elevated, resulting in pitiable clinical outcomes. According to increasing research, multiple E3 ligases, in addition to UBDs work together to modulate HIF expression and activity, permitting breast cancer cells to make out a hypoxic milieu. On the other hand, hypoxia and HIF signaling regulate numerous E3 ligases as well as DUBs. Interpreting involved networks connecting E3 ligase, DUBS, and HIF will reveal profound mechanisms of physiological response to hypoxia and aid in the discovery of new molecular references for cancer management. The present state of knowledge about the entire kinship among E3 ligase, DUBs, and HIF signaling is reviewed here, emphasizing using E3 ligase or DUB inhibitors in breast cancer.

Network pharmacology and molecular docking analysis on the mechanism of Wensan tincture in the treatment of pulmonary nodules: A review.

Network pharmacology and molecular docking methods were applied to elucidate the molecular mechanism of action of Wensan tincture (WST) in the treatment of pulmonary nodules. The Traditional Chinese Medicine Systems Pharmacology and the Traditional Chinese Medicine and Chemical Composition database were used to screen the active ingredients. Potential targets of WST were retrieved using Traditional Chinese Medicine Systems Pharmacology, SwissADME, and SwissTargetPrediction, while pulmonary nodule-associated targets were obtained from GeneCards and Online Mendelian Inheritance in Man databases. An active ingredient-target network was constructed using Cytoscape 3.9.1, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted via the Database for Annotation, Visualization, and Integrated Discovery platform to identify core targets and signaling pathways. Molecular docking studies were performed using AutoDockTools. The results revealed 62 active ingredients and 344 corresponding targets within the tincture, alongside 1005 targets associated with pulmonary nodules. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the potential therapeutic targets of WST include signal transducer and activator of transcription 3, mitogen-activated protein kinase-3, mitogen-activated protein kinase-1, Jun proto-oncogene, tumor protein 53, phosphoinositide-3-kinase regulatory subunit 1, heat shock protein 90 alpha family class A member 1, and AKT serine/threonine kinase 1. The primary pathways were the cancer pathway, mitogen-activated protein kinase signaling, advanced glycation end-products and their receptor signaling, epidermal growth factor receptor signaling, hypoxia-inducible factor-1 signaling, and the programmed cell death-ligand 1/programmed cell death protein 1 checkpoint pathways. Molecular docking demonstrated that quercetin exhibited the strongest binding affinity with mitogen-activated protein kinase-3, with a binding energy of -9.1 kcal/mol. Notably, key components of WST, such as quercetin, demonstrate considerable potential as drug candidates for the treatment of pulmonary nodules.

Hypoxia-inducible factor activators: a novel class of oral drugs for the treatment of anemia of chronic kidney disease.

Anemia is a hallmark of chronic kidney disease (CKD), worsens with disease progression, and profoundly affects a patient's well-being. Major pathogenic factors are inadequate kidney erythropoietin (EPO) production and absolute and functional iron deficiency. The 2 mainstays of current anemia treatment are a) replacement therapy with recombinant EPO or 1 of its glycosylated derivatives, administered subcutaneously or intravenously, and b) intravenous (IV) iron injections. Over the past 5 years, hypoxia-inducible factor (HIF)-prolyl hydroxylase inhibitors (HIF-PHIs) have been approved in many countries for the management of anemia in both nondialysis and dialysis-dependent patients with CKD. Due to cardiovascular safety concerns, only 2 HIF-PHIs, daprodustat and vadadustat, have been approved for marketing in the United States, and only for patients on maintenance dialysis. HIF-PHIs are oral agents that are effective at improving and maintaining hemoglobin levels by activating HIF signaling in anemic patients with CKD. They stimulate the production of endogenous EPO, increase total iron-binding capacity through their direct effects on transferrin gene transcription, lower plasma hepcidin indirectly, and have beneficial effects on red blood cell parameters. Here, we discuss the mechanisms of action and pharmacologic properties of different HIF-PHIs. We discuss unwanted on-target and off-target effects, review cardiovascular and other safety concerns, and provide a benefit/risk-based perspective on how this new class of oral drugs might impact current anemia management in CKD. A clinical case is presented that highlights the clinical complexities and therapeutic challenges in managing anemia in CKD.

Novel dysregulated long non-coding RNAs in the acute kidney injury-to-chronic kidney diseases transition unraveled by transcriptomic analysis.

Acute kidney injury (AKI)-to-chronic kidney disease (CKD) transition involves a complex pathomechanism, including inflammation, apoptosis, and fibrosis where long non-coding RNAs (lncRNAs) play a crucial role in their regulation. However, to date, only a few lncRNAs have been discovered to be involved in the AKI-to-CKD transition. Therefore, this study aims to investigate the dysregulated lncRNAs in the AKI-to-CKD transition invitro and invivo. To mimic AKI-to-CKD transition both invivo and invitro, bilateral ischemia-reperfusion (IR) kidney injury was performed in Wistar rats (male), and normal rat kidney epithelial cell (NRK52E) cells were treated with exogenous transforming growth factor-β1 (TGF-β1). Further processing and analysis of samples collected from these studies (e.g., biochemical, histopathology, immunofluorescence, and RNA isolation) were also performed, and transcriptomic analysis was performed to identify the dysregulated lncRNAs. Rats subjected to IR showed a significant increase in kidney injury markers (creatinine, blood urea nitrogen (BUN), kidney injury molecule-1(KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) along with altered cell morphology). Apoptosis, inflammation, and fibrosis markers were markedly increased during the AKI-to-CKD transition. Furthermore, transcriptomic analysis revealed 62 and 84 unregulated and 95 and 92 downregulated lncRNAs invivo and invitro, respectively. Additionally, functional enrichment analysis revealed their involvement in various pathways, including the tumor necrosis factor (TNF), wingless-related integration site (Wnt), and hypoxia-inducible factor-1 (HIF-1) signaling pathways. These identified dysregulated lncRNAs significantly contribute to AKI-to-CKD transition, and their knockin/out can aid in developing targeted therapeutic interventions against AKI-to-CKD transition.

Impact of Sublethal Insecticides Exposure on Vespa magnifica: Insights from Physiological and Transcriptomic Analyses.

Insecticides are widely used to boost crop yields, but their effects on non-target insects like Vespa magnifica are still poorly understood. Despite its ecological and economic significance, Vespa magnifica has been largely neglected in risk assessments. This study employed physiological, biochemical, and transcriptomic analyses to investigate the impact of sublethal concentrations of thiamethoxam, avermectin, chlorfenapyr, and β-cypermethrin on Vespa magnifica. Although larval survival rates remained unchanged, both pupation and fledge rates were significantly reduced. Enzymatic assays indicated an upregulation of superoxide dismutase and catalase activity alongside a suppression of peroxidase under insecticide stress. Transcriptomic analysis revealed increased adenosine triphosphate-related processes and mitochondrial electron transport activity, suggesting elevated energy expenditure to counter insecticide exposure, potentially impairing essential functions like flight, hunting, and immune response. The enrichment of pathways such as glycolysis, hypoxia-inducible factor signaling, and cholinergic synaptic metabolism under insecticide stress highlights the complexity of the molecular response with notable effects on learning, memory, and detoxification processes. These findings underscore the broader ecological risks of insecticide exposure to non-target insects and highlight the need for further research into the long-term effects of newer insecticides along with the development of strategies to safeguard beneficial insect populations.

Ecological adaptations of amphibians to environmental changes along an altitudinal gradient (Case Study: Bufo gargarizans) from phenotypic and genetic perspectives

BackgroundOrganisms have evolved a range of phenotypic and genetic adaptations to live in different environments along an altitudinal gradient. Herein, we studied the widely distributed Chinese toad, Bufo gargarizans, as a model and used an integrated phenotype-genotype approach to assess adaptations to different altitudinal environments.ResultsComparison of populations from four altitudes (50 m, 1200 m, 2300 m, and 3400 m) showed more effective defenses among high-altitude toads. These included thickened epidermis, more epidermal capillaries and granular glands, greater gland size in skin, and higher antioxidant enzyme activities in plasma. High-altitude toads also showed increased erythrocytes and hematocrit and elevated hemoglobin concentration, potentially improving oxygen delivery. Elevated altitude led to a metabolic shift from aerobic to anaerobic metabolism, and high-altitude populations favored carbohydrates over fatty acids to fuel for energy metabolism. Differentially expressed genes were associated with adaptive phenotypic changes. For instance, expression of genes associated with fatty acid metabolism showed greater suppression at high altitude (3400 m), consistent with decreased flux of β-hydroxybutyric acid and lower free fatty acids levels. Moreover, down-regulation of genes involved in carbon metabolism processes at high altitude (3400 m) were coincident with reduced TCA cycle flux. These results suggest that high-altitude toads adopt a metabolic suppression strategy for survival under harsh environmental conditions. Moreover, the hypoxia-inducible factor signaling cascade was activated at high altitude.ConclusionsCollectively, these results advance our comprehension of adaptation to high-altitude environments by revealing physiological and genetic mechanisms at work in Chinese toads living along altitudinal gradients.

Network-based pharmacology and experimental validation to explore the mechanism of action of the Jiawei Pentongling formula for the treatment of endometriosis-related pain.

To investigate the effects and mechanisms of the Jiawei Pentongling formula (, JWPTL) in treating endometriosis-related pain using network pharmacology study and experimental validation. Active ingredients and relevant targets of JWPTL, as well as genes for endometriosis-related pain, were collected from public databases. Prediction of core targets and pathways of JWPTL against pain associated with endometriosis by protein-protein interaction (PPI) network work, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis. The Sprague-Dawley rat endo-metriosis model was constructed using the autologous endosomal transplantation method, and the successfully modeled rats were randomly divided into the model group and the JWPTL group, with 8 rats in each group. Another 8 rats were set up in the sham group. Rats in the JWPTL group used the rectal delivery method with the addition of JWPTL (7.77 g·kg-1·d-1) once a day for 28 d. Rats in the model and sham-operated groups were given equal amounts of saline using the same administration method. The 50% paw withdrawal threshold (PWT) of the rats was measured at different time points. After the intervention, the expression of phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt) proteins and mRNA in endometriotic tissues was detected by immune-ohistochemistry and reverse transcription-polymerase chain reaction. From GeneCards, Online Mendelian Inheritance in Man and other databases, a total of 964 endometriosis (EMs) -related pain targets were screened, 142 active ingredients of JWPTL, 605 targets, and 221 potential targets were obtained by intersection of Venn diagram; 44 core targets were identified by constructing PPI network. KEGG enrichment analysis showed that JWPTL mainly involves the PI3K-Akt signaling pathway, estrogen signaling pathway, hypoxia inducible factor-1 signaling pathway, tumour necrotizing factor signaling pathway, and other signaling pathways in the treatment of EMs-related pain. Animal experiments showed that JWPTL could up-regulate the mechanical pain threshold and reduce the expression of PI3K and Akt proteins and mRNA in ectopic endometrial tissues of model rats. The present study preliminarily analyzed the pharmacological mechanism of the formula, and molecular docking and animal experiments showed the feasibility of this study, suggesting that the formula may inhibit the release of inflammatory factors and reverse the pain associated with EMs by downregulating the PI3K/Akt signaling pathway.

Single-cell profiling reveals a conserved role for hypoxia-inducible factor signaling during human craniotomy infection

Neurosurgeries complicated by infection are associated with prolonged treatment and significant morbidity. Craniotomy is a common neurosurgical procedure; however, the cellular and molecular signatures associated with craniotomy infection in human subjects are unknown. A retrospective study of over 2,500 craniotomies reveals diverse patient demographics, pathogen identity, and surgical landscapes associated with infection. Leukocyte profiling in patient tissues from craniotomy infection characterizes a predominance of granulocytic myeloid-derived suppressor cells that may arise from transmigrated blood neutrophils, based on single-cell RNA sequencing (scRNA-seq) trajectory analysis. Single-cell transcriptomic analysis identifies metabolic shifts in tissue leukocytes, including a conserved hypoxia-inducible factor (HIF) signature. The importance of HIF signaling was validated using a mouse model of Staphylococcus aureus craniotomy infection, where HIF inhibition increases chemokine production and leukocyte recruitment, exacerbating tissue pathology. These findings establish conserved metabolic and transcriptional signatures that may represent promising future therapeutic targets for human craniotomy infection in the face of increasing antimicrobial resistance.

Endothelial PHD2 deficiency induces apoptosis resistance and inflammation via AKT activation and AIP1 loss independent of HIF2α.

In hypoxic and pseudohypoxic rodent models of pulmonary hypertension (PH), hypoxia-inducible factor (HIF) inhibition attenuates disease initiation. However, HIF activation alone, due to genetic alterations or use of inhibitors of prolyl hydroxylase domain (PHD) enzymes, has not been definitively shown to cause PH in humans, indicating the involvement of other mechanisms. Given the association between endothelial cell dysfunction and PH, the effects of pseudohypoxia and its underlying pathways were investigated in primary human lung endothelial cells. PHD2 silencing or inhibition, while activating HIF2α, induced apoptosis-resistance and IFN/STAT activation in endothelial cells, independent of HIF signaling. Mechanistically, PHD2 deficiency activated AKT and ERK, inhibited JNK, and reduced AIP1 (ASK1-interacting protein 1), all independent of HIF2α. Like PHD2, AIP1 silencing affected these same kinase pathways and produced a similar dysfunctional endothelial cell phenotype, which was partially reversed by AKT inhibition. Consistent with these in vitro findings, AIP1 protein levels in lung endothelial cells were decreased in Tie2-Cre/Phd2 knockout mice compared with wild-type controls. Lung vascular endothelial cells from patients with pulmonary arterial hypertension (PAH) showed IFN/STAT activation. Lung tissue from both SU5416/hypoxia PAH rats and patients with PAH all showed AKT activation and dysregulated AIP1 expression. In conclusion, PHD2 deficiency in lung vascular endothelial cells drives an apoptosis-resistant and inflammatory phenotype, mediated by AKT activation and AIP1 loss independent of HIF signaling. Targeting these pathways, including PHD2, AKT, and AIP1, holds the potential for developing new treatments for endothelial dysfunction in PH.NEW & NOTEWORTHY HIF activation alone does not conclusively lead to human PH, suggesting that HIF-independent signaling may also contribute to hypoxia-induced PH. This study demonstrated that PHD2 silencing-induced pseudohypoxia in human lung endothelial cells suppresses apoptosis and activates STAT, effects that persist despite HIF2α inhibition or knockdown and are attributed to AKT and ERK activation, JNK inhibition, and AIP1 loss. These findings align with observations in lung endothelial cells and tissues from PAH rodent models and patients.

HIF signaling in the prothoracic gland regulates growth and development in hypoxia but not normoxia in Drosophila.

The developmental regulation of body size is a fundamental life-history characteristic that in most animals is tied to the transition from juvenile to adult form. In holometabolous insects, this transition is ostensibly initiated at the attainment of a critical weight in the final larval instar. It has been hypothesized that the size-sensing mechanism used to determine attainment of critical weight exploits oxygen limitation as a larvae grows beyond the oxygen-delivery capacity of its fixed tracheal system; that is, developmentally induced cellular hypoxia initiates the synthesis of the molting hormone ecdysone by the prothoracic gland. We tested this hypothesis in Drosophila by assaying cellular hypoxia throughout the third larval instar at 21 and 10 kPa O2, using the activity of the HIF (hypoxia inducible factor)-signaling pathway as a measure of hypoxia. While HIF signaling was elevated at low levels of environmental O2, it did not markedly increase during development at either oxygen level, and was only suppressed by hyperoxia after feeding had ceased. Further, changes in HIF signaling in the prothoracic gland alone did not alter body size or developmental time in a way that would be expected if cellular hypoxia in the prothoracic gland was part of the critical weight mechanism. Our data do show, however, that reduced HIF signaling in the prothoracic gland decreases survival and retards development at 10 kPa O2, suggesting that prothoracic HIF signaling is a necessary part of the beneficial plasticity mechanism that controls growth and development in response to low oxygen level.

Vitamin B12 ameliorates gut epithelial injury via modulating the HIF-1 pathway and gut microbiota

Inflammatory bowel diseases (IBDs) are immune chronic diseases characterized by recurrent episodes, resulting in continuous intestinal barrier damage and intestinal microbiota dysbiosis. Safe strategies aimed at stabilizing and reducing IBDs recurrence have been vigorously pursued. Here, we constructed a recurrent intestinal injury Drosophila model and found that vitamin B12 (VB12), an essential co-factor for organism physiological functions, could effectively protect the intestine and reduce dextran sulfate sodium-induced intestinal barrier disruption. VB12 also alleviated microbial dysbiosis in the Drosophila model and inhibited the growth of gram-negative bacteria. We demonstrated that VB12 could mitigate intestinal damage by activating the hypoxia-inducible factor-1 signaling pathway in injured conditions, which was achieved by regulating the intestinal oxidation. In addition, we also validated the protective effect of VB12 in a murine acute colitis model. In summary, we offer new insights and implications for the potential supportive role of VB12 in the management of recurrent IBDs flare-ups.

Insoluble HIFa protein aggregates by cadmium disrupt hypoxia-prolyl hydroxylase (PHD)-hypoxia inducible factor (HIFa) signaling in renal epithelial (NRK-52E) and interstitial (FAIK3-5) cells

The kidney is the main organ that senses changes in systemic O2 pressure by hypoxia-PHD-HIFa (HPH) signaling, resulting in adaptive target gene activation, including erythropoietin (EPO). The non-essential transition metal cadmium (Cd) is nephrotoxic and disrupts the renal HPH pathway, which may promote Cd-associated chronic renal disease (CKD). A deeper molecular understanding of Cd interference with renal HPH signaling is missing, and no data with renal cell lines are available. In rat kidney NRK-52E cells, which model the proximal tubule, and murine fibroblastoid atypical interstitial kidney (FAIK3-5) cells, which mimic renal EPO-producing cells, the chemical hypoxia mimetic dimethyloxalylglycine (DMOG; 1 mmol/l) or hypoxia (1% O2) activated HPH signaling. Cd2+ (2.5–20 µmol/l for ≤ 24 h) preferentially induced necrosis (trypan blue uptake) of FAIK3-5 cells at high Cd whereas NRK-52E cells specially developed apoptosis (PARP-1 cleavage) at all Cd concentrations. Cd (12.5 µmol/l) abolished HIFa stabilization and prevented upregulation of target genes (quantitative real-time polymerase chain reaction and immunoblotting) induced by DMOG or hypoxia in both cell lines, which was caused by the formation of insoluble HIFa aggregates. Strikingly, hypoxic preconditioning (1% O2 for 18 h) reduced apoptosis of FAIK3-5 and NRK-52E cells at low Cd concentrations and decreased insoluble HIFa proteins. Hence, drugs mimicking hypoxic preconditioning could reduce CKD induced by chronic low Cd exposure.

Enhanced tumor response to adoptive T cell therapy with PHD2/3-deficient CD8 T cells

While adoptive cell therapy has shown success in hematological malignancies, its potential against solid tumors is hindered by an immunosuppressive tumor microenvironment (TME). In recent years, members of the hypoxia-inducible factor (HIF) family have gained recognition as important regulators of T-cell metabolism and function. The role of HIF signalling in activated CD8 T cell function in the context of adoptive cell transfer, however, has not been explored in full depth. Here we utilize CRISPR-Cas9 technology to delete prolyl hydroxylase domain-containing enzymes (PHD) 2 and 3, thereby stabilizing HIF-1 signalling, in CD8 T cells that have already undergone differentiation and activation, modelling the T cell phenotype utilized in clinical settings. We observe a significant boost in T-cell activation and effector functions following PHD2/3 deletion, which is dependent on HIF-1α, and is accompanied by an increased glycolytic flux. This improvement in CD8 T cell performance translates into an enhancement in tumor response to adoptive T cell therapy in mice, across various tumor models, even including those reported to be extremely resistant to immunotherapeutic interventions. These findings hold promise for advancing CD8 T-cell based therapies and overcoming the immune suppression barriers within challenging tumor microenvironments.

Effect of Different Dietary Iron Contents on Liver Transcriptome Characteristics in Wujin Pigs.

Iron is an important trace element that affects the growth and development of animals and regulates oxygen transport, hematopoiesis, and hypoxia adaptations. Wujin pig has unique hypoxic adaptability and iron homeostasis; however, the specific regulatory mechanisms have rarely been reported. This study randomly divided 18 healthy Wujin piglets into three groups: the control group, supplemented with 100 mg/kg iron (as iron glycinate); the low-iron group, no iron supplementation; and the high-iron group, supplemented with 200 mg/kg iron (as iron glycinate). The pre-feeding period was 5 days, and the formal period was 30 days. Serum was collected from empty stomachs before slaughter and at slaughter to detect changes in the serum iron metabolism parameters. Gene expression in the liver was analyzed via transcriptome analysis to determine the effects of low- and high-iron diets on transcriptome levels. Correlation analysis was performed for apparent serum parameters, and transcriptome sequencing was performed using weighted gene co-expression network analysis to reveal the key pathways underlying hypoxia regulation and iron metabolism. The main results are as follows. (1) Except for the hypoxia-inducible factor 1 (HIF-1) content (between the low- and high-iron groups), significant differences were not observed among the serum iron metabolic parameters. The serum HIF-1 content of the low-iron group was significantly higher than that of the high-iron group (p < 0.05). (2) Sequencing analysis of the liver transcriptome revealed 155 differentially expressed genes (DEGs) between the low-iron and control groups, 229 DEGs between the high-iron and control groups, and 279 DEGs between the low- and high-iron groups. Bioinformatics analysis showed that the HIF-1 and transforming growth factor-beta (TGF-β) signaling pathways were the key pathways for hypoxia regulation and iron metabolism. Four genes were selected for qPCR validation, and the results were consistent with the transcriptome sequencing data. In summary, the serum iron metabolism parameter results showed that under the influence of low- and high-iron diets, Wujin piglets maintain a steady state of physiological and biochemical indices via complex metabolic regulation of the body, which reflects their stress resistance and adaptability. The transcriptome results revealed the effects of low-iron and high-iron diets on the gene expression level in the liver and showed that the HIF-1 and TGF-β signaling pathways were key for regulating hypoxia adaptability and iron metabolism homeostasis under low-iron and high-iron diets. Moreover, HIF-1α and HEPC were the key genes. The findings provide a theoretical foundation for exploring the regulatory pathways and characteristics of iron metabolism in Wujin pigs.

Design, synthesis and biological activity of α-nitrile substituted guaiazulene-based chalcone derivatives

In present study, seventeen α-nitrile substituted guaiazulene-based chalcone derivatives including twelve new were designed, synthesized, and assayed for antiviral, cytotoxicity and signal pathway activities. All derivatives showed potential antiviral activity towards influenza virus or herpes simplex virus (HSV), 7 g with the substitution of nitro group showed strong effects towards H1N1 virus at 30 μM with inhibitory rate of 66.0%, 7o with thiophene exhibited potent anti HSV-1 activities with inhibitory rate of 65.8%. Moreover, several compounds exhibited inhibitory effects on tumor cells and hypoxia-inducible factor-1 (HIF1) signaling pathways. These results showed that α-nitrile substituted guaiazulene-based chalcones offered a promising framework for the further development of new highly efficient drugs.

Integrated Network Pharmacology and Molecular Docking to Explore the Mechanisms of Ningshen Wendan Decoction in the Treatment of Schizophrenia.

Schizophrenia (SCZ) is a prevalent chronic mental disorder characterized by a high recurrence rate and significant disability. Currently, no satisfactory pharmacological treatments have been identified. Although Ningshen Wendan decoction (NSWDD) has shown promising results in improving cognitive function in patients with schizophrenia, its underlying mechanism of action remains unclear. This study systematically investigated the mechanisms of NSWDD in SCZ treatment using network pharmacology and molecular docking approaches. Analysis of the interaction genes revealed 307 common targets of NSWDD and SCZ. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated the involvement of multiple signaling pathways including interleukin 17 signaling pathway, multiple virus infections, Advanced glycosylation end products (AGEs) - receptor of AGEs (AGEs-RAGE) signaling pathway, tumor necrosis factor signaling pathway, and Hypoxia-inducible factor-1 (HIF-1) signaling pathway as key pathways influenced by NSWDD in treating SCZ. These pathways are associated with various biological processes such as transcriptional regulation, apoptosis regulation, gene expression regulation, and external stimulus-response. Molecular docking simulations indicated favorable binding interactions between components of NSWDD and target proteins via intermolecular forces. The study provided initial insights into the internal molecular mechanisms underlying the beneficial effect of NSWDD on SCZ through multi-target modulation across multiple pathways.

Targeting Hypoxia and HIF1α in Triple-Negative Breast Cancer: New Insights from Gene Expression Profiling and Implications for Therapy.

Breast cancer is a complex and multifaceted disease with diverse risk factors, types, and treatment options. Triple-negative breast cancer (TNBC), which lacks the expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2), is the most aggressive subtype. Hypoxia is a common feature of tumors and is associated with poor prognosis. Hypoxia can promote tumor growth, invasion, and metastasis by stimulating the production of growth factors, inducing angiogenesis, and suppressing antitumor immune responses. In this study, we used mRNA-seq technology to systematically investigate the gene expression profile of MDA-MB-231 cells under hypoxia. We found that the hypoxia-inducible factor (HIF) signaling pathway is the primary pathway involved in the cellular response to hypoxia. The genes in which expression levels were upregulated in response to hypoxia were regulated mainly by HIF1α. In addition, hypoxia upregulated various genes, including Nim1k, Rimkla, Cpne6, Tpbgl, Kiaa11755, Pla2g4d, and Ism2, suggesting that it regulates cellular processes beyond angiogenesis, metabolism, and known processes. We also found that HIF1α was hyperactivated in MDA-MB-231 cells under normoxia. A HIF1α inhibitor effectively inhibited the invasion, migration, proliferation, and metabolism of MDA-MB-231 cells. Our findings suggest that hypoxia and the HIF signaling pathway play more complex and multifaceted roles in TNBC than previously thought. These findings have important implications for the development of new therapeutic strategies for TNBC.

Deubiquitinating enzyme mutagenesis screens identify a USP43-dependent HIF-1 transcriptional response

The ubiquitination and proteasome-mediated degradation of Hypoxia Inducible Factors (HIFs) is central to metazoan oxygen-sensing, but the involvement of deubiquitinating enzymes (DUBs) in HIF signalling is less clear. Here, using a bespoke DUBs sgRNA library we conduct CRISPR/Cas9 mutagenesis screens to determine how DUBs are involved in HIF signalling. Alongside defining DUBs involved in HIF activation or suppression, we identify USP43 as a DUB required for efficient activation of a HIF response. USP43 is hypoxia regulated and selectively associates with the HIF-1α isoform, and while USP43 does not alter HIF-1α stability, it facilitates HIF-1 nuclear accumulation and binding to its target genes. Mechanistically, USP43 associates with 14-3-3 proteins in a hypoxia and phosphorylation dependent manner to increase the nuclear pool of HIF-1. Together, our results highlight the multifunctionality of DUBs, illustrating that they can provide important signalling functions alongside their catalytic roles.