Acrolein, a highly reactive α,β-unsaturated aldehyde, is a widespread environmental pollutant. It is generated during the incomplete combustion of materials such as tobacco smoke, petrol, coal, forest fires, and plastics, as well as from the overheating of frying oils. Acrolein is known to induce cellular damage and oxidative stress. This study investigates the critical role of hypoxia-inducible factor 1α (HIF-1α), which is a transcription factor required to regulate cell survival and angiogenesis, in protecting bronchial epithelial cells from acrolein-induced cytotoxicity and DNA damage under normoxic and hypoxic conditions. To our knowledge, no prior study has comprehensively evaluated the effects of HIF-1α on cellular responses to acrolein under normoxic and hypoxic conditions in vitro. Therefore, the goal of this study was to explore how silencing HIF-1α influences cellular responses to acrolein, and our study focused on changes in cytotoxicity, metabolic activity, DNA damage, and oxidative stress using the BEAS-2B cell line. We observed enhanced cell damage and reduced viability in cells exposed to acrolein when silenced with HIF-1α, particularly in hypoxic environments. While results indicate that silencing HIF-1α significantly increases cytotoxicity and DNA damage under hypoxia compared to normoxic conditions, oxidative stress indicator levels did not rise noticeably under hypoxia following HIF-1α silencing. This research warrants further investigation to indicate the importance of HIF-1α in adapting to environmental and hypoxic stressors, which are commonly found in chronic lung diseases and ischemic conditions.

Zinc oxide nanoparticles (nZnO) are increasingly utilized in industrial, medical, and personal care products, particularly as the main ingredient in sunscreens, raising concerns about their environmental impact, especially in coastal ecosystems. The Baltic Sea, experiencing severe eutrophication, faces persistent hypoxia due to excessive nutrient runoff and limited water exchange. Simultaneously, coastal pollution from industrial and urban activities introduces nZnO, a highly biotoxic nanopollutant. The combined effects of hypoxia and nZnO contamination may amplify environmental stress, yet their interactions remain insufficiently studied. This study investigates the combined effects of nZnO exposure and fluctuating dissolved oxygen regimes (specifically short- and long-term hypoxia and subsequent reoxygenation) on Mytilus edulis, a sentinel species in these ecosystems. By assessing a range of cellular and molecular markers, including oxidative stress, oxygen sensing, protein quality control, stress response, apoptosis, and inflammation, we show that nZnO exacerbates hypoxia-induced oxidative stress, delaying redox recovery and prolonging oxidative damage during reoxygenation. Specifically, nZnO exposure maintains elevated LPO and PC levels after reoxygenation, indicating prolonged oxidative imbalance. While M. edulis typically recovers from hypoxia-induced stress, nZnO disrupts this process by impairing antioxidant defenses, prolonging HIF-1α activation, and dysregulating p53, JNK, and p38 expression, thereby interfering with normal hypoxia-reoxygenation response. Additionally, nZnO alters HSP70, Lon protease, and caspase-3 regulation, disrupting protein-folding and apoptotic pathways. These findings suggest a synergistic interaction between nZnO and hypoxia, heightening the organism's vulnerability to environmental stress and suggesting risks for marine organisms in nanoparticle-polluted, hypoxia-prone coastal regions.

Hypoxia tolerance is mainly controlled by the hypoxia signaling pathway and HIF-1α/2α serve as master regulators in this pathway. Here we identify MYLIP, an E3 ubiquitin ligase thought to specifically target lipoprotein receptors, as a downstream target of HIF-2α and a negative regulator of both HIF-1α and HIF-2α. MYLIP interacts with HIF-1α/2α and catalyzes K27-linked polyubiquitination at lysine 118/442 (HIF-1α) or lysine 117 (HIF-2α). This modification induces proteasomal degradation of HIF-1α, resulting in inhibition of hypoxia signaling. Furthermore, Mylip-deficient bluntsnout bream, zebrafish and mice are more tolerant to hypoxia. These findings reveal a role for MYLIP in regulating hypoxia signaling and identify a target for the development of fish strains with high hypoxia tolerance for the benefit of the aquaculture industry.

NEAT1 (Nuclear Enriched Abundant Transcript 1) is a long non-coding RNA playing a critical role in both physiological and pathological settings by directly modulating a variety of biological events, including transcriptional regulation, RNA processing, and chromatin remodeling. Multiple evidence demonstrated that different transcription factors and signaling pathways modulate biological processes by tightly regulating NEAT1 expression. These regulatory mechanisms act at different levels, allowing cells to rapidly modulate NEAT1 expression and dynamically respond to sudden changes in cellular conditions. In this review, we summarize and discuss the transcriptional routes controlling NEAT1 expression, emphasizing recent evidence showing the pivotal role of NEAT1 in regulating important biological processes, such as cellular stress response, inflammation, and cell differentiation.

During the first stages of embryonic development, the placenta develops under very low oxygen tension (∼1%-2% O2), so we sought to determine the regulatory role of oxygen in human trophoblast stem cells (hTSCs). We find that low oxygen promotes hTSC self-renewal but inhibits differentiation to syncytiotrophoblast (STB) and extravillous trophoblast (EVT). The transcription factor GCM1 (glial cell missing transcription factor 1) is downregulated in low oxygen, and concordantly, there is substantial reduction of GCM1-regulated genes in hypoxic conditions. Knockout of GCM1 in hTSC likewise impaired EVT and STB formation. Treatment with a phosphatidylinositol 3-kinase (PI3K) inhibitor reported to reduce GCM1 protein levels likewise counteracts spontaneous or directed differentiation. Additionally, chromatin immunoprecipitation of GCM1 showed binding near key genes upregulated upon differentiation including the contact inhibition factor CDKN1C. Loss of GCM1 resulted in downregulation of CDKN1C and corresponding loss of contact inhibition, implicating GCM1 in regulation of this critical process.

Tuning protein expression by targeting RNA structure using small molecules is an unexplored avenue for cancer treatment. To understand whether this vulnerability could be therapeutically targeted in the most lethal form of prostate cancer, castration-resistant prostate cancer (CRPC), we use a clinical small molecule, zotatifin, that targets the RNA helicase and translation factor eukaryotic initiation factor 4A (eIF4A). Zotatifin represses tumorigenesis in patient-derived and xenograft models and prolonged survival in vivo alongside hormone therapy. Genome-wide transcriptome, translatome, and proteomic analysis reveals two important translational targets: androgen receptor (AR), a key oncogene in CRPC, and hypoxia-inducible factor 1A (HIF1A), an essential cancer modulator in hypoxia. We solve the structure of the 5' UTRs of these oncogenic mRNAs and strikingly observe complex structural remodeling of these select mRNAs by this small molecule. Remarkably, tumors treated with zotatifin become more sensitive to anti-androgen therapy and radiotherapy. Therefore, "translatome therapy" provides additional strategies to treat the deadliest cancers.

Compartmentalization of multiple enzymes in cellulo and in vitro is a means of controlling the cascade reaction of metabolic enzymes. The compartmentation of enzymes through liquid-liquid phase separation may facilitate the reversible control of biocatalytic cascade reactions, thereby reducing the transcriptional and translational burden. This has attracted attention as a potential application in bioproduction. Recent research has demonstrated the existence and regulatory mechanisms of various enzyme compartments within cells. Mounting evidence suggests that enzyme compartmentation allows in vitro and in vivo regulation of cellular metabolism. However, the comprehensive regulatory mechanisms of enzyme condensates in cells and ideal organization of cellular systems remain unknown. This review provides an overview of the recent progress in multiple enzyme compartmentation in cells and summarizes strategies to reconstruct multiple enzyme assemblies in vitro and in cellulo. By examining parallel examples, we have evaluated the consensus and future perspectives of enzyme condensation.

Cardiovascular disease remains the leading cause of death globally, and drugs for new targets are urgently needed. Mitochondria are the primary sources of cellular energy, play crucial roles in regulating cellular homeostasis, and are tightly associated with pathological processes in cardiovascular disease. In response to physiological signals and external stimuli in cardiovascular disease, mitochondrial quality control, which mainly includes mitophagy, mitochondrial dynamics, and mitochondrial biogenesis, is initiated to meet cellular requirements and maintain cellular homeostasis. Traditional Chinese Medicine (TCM) has been shown to have pharmacological effects on alleviating cardiac injury in various cardiovascular diseases, including myocardial ischemia/reperfusion, myocardial infarction, and heart failure, by regulating mitochondrial quality control. Recently, several molecular mechanisms of TCM in the treatment of cardiovascular disease have been elucidated. However, mitochondrial quality control by TCM for treating cardiovascular disease has not been investigated. In this review, we aim to decipher the pharmacological effects and molecular mechanisms of TCM in regulating mitochondrial quality in various cardiovascular diseases. We also present our perspectives regarding future research in this field.

Inflammation and metabolic reprogramming are hallmarks of cardiovascular disorders, wherein myocardiocytes switch from fatty acids to glucose to yield energy. This has also been found in the myocardium of patients with calcific aortic valve disease, a prevalent disease exhibiting features of inflammatory disease that lacks pharmacological treatments. Therefore, we posited that the analysis of proinflammatory and metabolic mechanisms might give cues to disclose therapeutic targets.

The metabolic analysis of aortic valve interstitial cells (VIC) explanted from human valves was performed by Seahorse real-time cell metabolic analysis, fluxomics using ultra-performance liquid chromatography/mass spectrometry, quantitative polymerase chain reaction, metabolite quantitation, and loss-of-function experiments with gene silencing and pharmacological approaches. Findings were validated in quiescent VIC, 3-dimensional porcine VIC-valve endothelial cell cocultures, as well as in valve leaflets and VIC from human patients.

The hyperglycolytic program present in calcific aortic valve disease was replicated in control/nonstenotic VIC by cytokine exposure and enhanced by pathogen-associated molecular patterns. Inflammatory stimuli increased fluxes in glycolysis, tricarboxylic acid cycle, and the pentose phosphate pathway. Inflamed VIC exhibited increased glycolytic ATP production and lactate secretion, as well as changes in redox state and metabolic gene profile, that is, upregulation of glycolytic enzyme expression and downregulation of G6PD (glucose-6-phosphate dehydrogenase), the rate-limiting enzyme of the oxidative phase of pentose phosphate pathway. Notably, these alterations were replicated in quiescent VIC and 3-dimensional VIC-valve endothelial cell cocultures and are observed in diseased valves from patients. Strikingly, metabolic rewiring in control VIC was required for inflammation-triggered calcification and differentiation. A Food and Drug Administration-approved JAK (Janus kinase) inhibitor blunted these changes, whose major drivers are the JAK-STAT system, HIF (hypoxia-inducible factor)-1α, and NF-κB (nuclear factor-κB).

Inflammation reprograms VIC metabolism to support calcification by downregulating oxidative phase of pentose phosphate pathway and enhancing glycolytic flux and oxidative stress. These findings parallel the metabolic profile of stenotic VIC and provide novel therapeutic clues.

Infection generates localized hypoxia in affected tissue, inducing cellular survival responses and modulating inflammatory processes. Consideration of oxygen status as a parameter in in vitro infection research is therefore vital to the generation of physiologically relevant data within the 3R context. In this study, we characterize the culture morphology and oxygenation of liquid-liquid interface (LLI) permanent bronchial epithelial (Calu-3), classical air-liquid interface (cALI) Calu-3, and cALI human primary bronchial epithelial cell (hBEC) models under the normoxic conditions within standard incubators, commonly employed in in vitro work. We compare the normoxic state of these models to their hypoxic state to assess changes in the airway epithelial environment in response to oxygen deprivation, and the extent to which select hypoxia responses can be observed at the molecular level. Additional juxtapositions are drawn between Calu-3 LLI and cALI models and Calu-3 conventional monolayer (CM) and inverted air-liquid interface (iALI) models, due to their relevance for basic and specialized research, respectively. Epithelial complexity was observed to vary amongst the filter-based models, and all models were found to exhibit characteristic extracellular oxygen depletion patterns under normoxia. Importantly, the extracellular oxygen contents of Calu-3 LLI, cALI, and CM models significantly decreased during normoxic incubation. Specific hypoxia responses through stabilization of HIF-1α, HIF-2α, and/or HIF-3α and alteration of ACE2 protein levels differed in response to both culture format and cell type. Therefore, while all models examined provide valuable opportunities for in vitro exploration, variation in their morphological, physiological, and molecular characteristics necessitates careful consideration during experimental design.

Brain arteriovenous malformation (BAVM) is a complex cerebrovascular disease characterized by an abnormal high-flow vascular network, which increases the risk of hemorrhage, particularly in young individuals. Endothelial dysfunction has traditionally been considered the primary cause, while the contributions of the microenvironment and glial cells have not been fully explored. Astrocytes, as a key component of the central nervous system, play a crucial role in regulating neurovascular function, maintaining the integrity of the blood-brain barrier, and ensuring neural homeostasis. However, under the pathological conditions of BAVM, the phenotypic changes in astrocytes and their role in disease progression remain poorly understood. In our study, we emphasized the critical role of neuroinflammation and hypoxia in the progression of BAVM within its pathological microenvironment. Specifically, reactive astrocytes undergo phenotypic changes under these pathological conditions, significantly promoting vascular instability. Moreover, nitric oxide (NO) produced by BAVM endothelial cells activates signaling pathways that stabilize HIF-1α in astrocytes, initiating a "hypoxic" gene program under normoxic conditions. Furthermore, we discovered that COX-2, a direct target gene of HIF-1α, is upregulated in the BAVM microenvironment. These changes promoted endothelial dysfunction and vascular fragility, creating a vicious cycle that exacerbates hemorrhage risk. The application of COX-2 inhibitors significantly reduced neuroinflammation, stabilized blood vessels, and decreased hemorrhage risk. Our findings highlighted the crucial interaction between the BAVM microenvironment and astrocytes in driving disease progression, suggesting that COX-2 could be a potential therapeutic target for stabilizing BAVM vessels and reducing hemorrhagic events.

Hypoxia plays a pivotal role in modulating immune responses, especially in neutrophils, which are essential components of the innate immune system. Hypoxia-inducible factor (HIF)-1α, a key transcription factor in hypoxic adaptation, regulates cellular metabolism and inflammatory responses. However, the impact of HIF-1α-dependent glycolysis on the formation of neutrophil extracellular traps (known as NETosis) under hypoxic conditions remains unclear.

We employed two established neutrophil models, neutrophils isolated from human whole blood and DMSO-induced dHL-60 cells, to explore the role of HIF-1α in regulating glycolysis and its influence on NETosis under hypoxic conditions. We utilized western blotting, immunofluorescence staining, ELISA, and flow cytometry to evaluate the expression of key glycolytic enzymes and NETosis markers under hypoxia. Additionally, the effects of inhibiting HIF-1α with LW6 and blocking the glycolytic pathway with Bay-876 were investigated.

HIF-1α-dependent glycolysis, through the upregulation of key glycolytic enzymes, significantly enhances NETosis under hypoxic conditions. Pharmacological inhibition of HIF-1α with LW6 and glycolytic blockade with Bay-876 markedly reduced NETosis, underscoring the crucial role of metabolic reprogramming in neutrophil function during hypoxia.

This study provides novel insights into the interplay between metabolic reprogramming and NETosis in response to hypoxic stress. We identify HIF-1α-dependent glycolysis as a key driver of NETs formation, advancing our understanding of the mechanisms underlying hypoxia-related inflammatory diseases. These findings also suggest that targeting metabolic pathways may offer potential therapeutic strategies for modulating immune responses in hypoxia-associated disorders.

Primordial germ cells (PGCs), the precursors of oocytes or spermatozoa, are highly pluripotent. In recent years, the in vitro induction of human primordial germ cell-like cells (hPGCLCs) has advanced significantly. However, the stability and efficacy of obtaining hPGCLCs in vitro still require further improvement. In the current study, we identified a novel induction system by using Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12 (DMEM/F-12) as the basal medium supplemented with B27 and N2 (referred to as N2B27) in combination with four cytokines: bone morphogenetic protein 4 (BMP4), stem cell factor (SCF), epidermal growth factor (EGF), and leukemia inhibitory factor (LIF). The hPGCLCs induced under these conditions closely resemble PGCs from 4 to 5-week-old embryos at the transcriptome level. Compared with traditional GK15 (GMEM supplemented with 15% Knockout™ SR)-based induction conditions, the N2B27 system significantly increased the speed and efficacy of hPGCLC induction. RNA sequencing analysis revealed that this improvement resulted from an increased cell capacity to cope with hypoxic stress and avoid apoptosis. The N2B27 medium promoted an increase in mitochondrial activity, enabling cells to better cope with hypoxic stress while also reducing the production of reactive oxygen species. Moreover, by gradient concentration experiments, we demonstrated that addition of the common antioxidant N-acetyl-L-cysteine at an optimized concentration further enhanced the efficiency of PGCLC induction under GK15 conditions. Thus, our study established an optimized induction system that enhances the efficiency of hPGCLC differentiation by improving cellular resilience to hypoxic stress and apoptosis.

Elevated brain levels of the essential metals manganese (Mn), copper, or iron induce motor disease. However, mechanisms of metal-induced motor disease are unclear and treatments are lacking. Elucidating the mechanisms of Mn-induced motor disease is particularly important because occupational and environmental Mn overexposure is a global public health problem. To address this, here we combined unbiased transcriptomics and metabolomics with functional studies in a mouse model of human environmental Mn exposure. Transcriptomics unexpectedly revealed that Mn exposure up-regulated expression of metabolic pathways in the brain and liver. Notably, genes in the kynurenine pathway of tryptophan metabolism, which produces neuroactive metabolites that impact neurological function, were up-regulated by Mn. Subsequent unbiased metabolomics revealed that Mn treatment altered kynurenine pathway metabolites in the brain and liver. Functional experiments then demonstrated that pharmacological inhibition of the first and rate-limiting step of the kynurenine pathway fully rescued Mn-induced motor deficits. Finally, elevated Mn directly activates hypoxia-inducible factor (HIF) transcription factors, and additional mechanistic assays identified a role for HIF1, but not HIF2, in regulating expression of hepatic kynurenine pathway genes under physiological or Mn exposure conditions, suggesting that Mn-induced HIF1 activation may contribute to the dysregulation of the kynurenine pathway in Mn toxicity. These findings (1) identify the upregulation of the kynurenine pathway by elevated Mn as a fundamental mechanism of Mn-induced motor deficits; (2) provide a pharmacological approach to treat Mn-induced motor disease; and (3) should broadly advance understanding of the general principles underlying neuromotor deficits caused by metal toxicity.

Endothelial cells (ECs) are arranged side-by-side to create a semi-permeable monolayer, forming the inner lining of every blood vessel (micro and macrocirculation). Serving as the first barrier for circulating molecules and cells, ECs represent the main regulators of vascular homeostasis being able to respond to environmental changes, either physical or chemical signals, by producing several factors that regulate vascular tone and cellular adhesion. Healthy endothelium has anticoagulant properties that prevent the adhesion of leukocytes and platelets to the vessel walls, contributing to resistance to thrombus formation, and regulating inflammation, and vascular smooth muscle cell proliferation. Many risk factors of cardiovascular diseases (CVDs) promote the endothelial expression of chemokines, cytokines, and adhesion molecules. The resultant endothelial activation can lead to endothelial cell dysfunction (ECD). In vitro models of ECD allow the study of cellular and molecular mechanisms of disease and provide a research platform for screening potential therapeutic agents. Even though alternative models are available, such as animal models or ex vivo models, in vitro models offer higher experimental flexibility and reproducibility, making them a valuable tool for the understanding of pathophysiological mechanisms of several diseases, such as CVDs. Therefore, this review aims to synthesize the currently available in vitro models regarding ECD, emphasizing CVDs. This work will focus on 2D cell culture models (endothelial cell lines and primary ECs), 3D cell culture systems (scaffold-free and scaffold-based), and 3D cell culture models (such as organ-on-a-chip). We will dissect the role of external stimuli-chemical and mechanical-in triggering ECD.

The therapeutic potential of presumed cardiac progenitor cells (CPCs) in heart regeneration has garnered significant interest, yet clinical trials have revealed limited efficacy due to challenges in cell survival, retention, and expansion. Priming CPCs to survive the hostile hypoxic environment may be key to enhancing their regenerative capacity. We demonstrate that microRNA-210 (miR-210), known for its role in hypoxic adaptation, significantly improves CPC survival by inhibiting apoptosis through the downregulation of Casp8ap2, a ~40% reduction in caspase activity, and a ~90% decrease in DNA fragmentation. Contrary to the expected induction of Bnip3-dependent mitophagy by hypoxia, miR-210 did not upregulate Bnip3, indicating a distinct anti-apoptotic mechanism. Instead, miR-210 reduced markers of mitophagy and increased mitochondrial biogenesis and oxidative metabolism, suggesting a role in metabolic reprogramming. Furthermore, miR-210 enhanced the secretion of paracrine growth factors from CPCs, with a ~1.6-fold increase in the release of stem cell factor and of insulin growth factor 1, which promoted in vitro endothelial cell proliferation and cardiomyocyte survival. These findings elucidate the multifaceted role of miR-210 in CPC biology and its potential to enhance cell-based therapies for myocardial repair by promoting cell survival, metabolic adaptation, and paracrine signalling.

Excessive fluoride exposure can lead to skeletal fluorosis (SF), and selenium deficiency is one of the important pathogenic factors of Kashin-Beck disease (KBD). Although the pathogenic factors of these two diseases vary, there are many similarities in their pathogenic mechanisms on skeletal and articular cartilage lesions. There are currently no specific drugs for either disease, and investigating their shared pathogenic mechanisms may facilitate the development of new drugs for the treatment. This study found through bioinformatics technology that the HIF-1 signaling pathway and ferroptosis pathway might exert significant effects in both SF and KBD. Targeted small molecule drug prediction was conducted for the above two signaling pathways, and quercetin was screened as the best candidate therapeutic drug. Meanwhile, molecular docking and molecular dynamics simulations once again validated our screening results. In summary, quercetin may alleviate the symptoms of SF and KBD by regulating the HIF-1 signaling pathway and the ferroptosis pathway. In other words, it can attain the objective of treating two diseases simultaneously with one drug. This will provide new theoretical references for the treatment of comorbidity.

Non-triple-helical collagen polypeptides (NTHs) are alternative gene products lacking the typical collagen triple-helical structure. This study investigated NTH production in tumour cells and tissues. NTH α1(IV) was detected in various human tumour cell lines and extracted from human lung cancer tissues and tumours in mice. NTH production was significantly affected by serum concentration and occurred under hypoxic or hypoxia-mimetic conditions, even with sufficient ascorbic acid. This suggests NTHs are produced under physiological hypoxia, potentially contributing to tumour angiogenesis. NTH production generally coincided with hypoxia-inducible factor-1α (HIF-1α) accumulation, except with cobalt chloride, indicating HIF-1α is not directly involved in NTH α1(IV) production. NTH electrophoretic mobility on SDS-PAGE was higher under hypoxia or deferoxamine treatment, likely due to suppressed lysyl hydroxylase 3 activity. This study demonstrates NTH production in tumour cells and tissues under hypoxia, suggesting their association with tumour angiogenesis and potential as therapeutic targets.

Atherosclerosis is a lipid disorder where modified lipids (especially oxidized LDL) induce macrophage foam cell formation in the aorta. Its pathogenesis involves a continuum of persistent inflammation accompanied by dysregulated anti-inflammatory responses. Changes in the immune cell status due to differences in the lesional microenvironment are crucial in terms of plaque development, its progression, and plaque rupture. Ly6Chi monocytes generated through both medullary and extramedullary cascades act as one of the major sources of plaque macrophages and thereby foam cells. Both monocytes and monocyte-derived macrophages also participate in pathological events in atherosclerosis-associated multiple organ systems through inter-organ communications. For years, macrophage phenotypes M1 and M2 have been shown to perpetuate inflammatory and resolution responses; nevertheless, such a dualistic classification is too simplistic and contains severe drawbacks. As the lesion microenvironment is enriched with multiple mediators that possess the ability to activate macrophages to diverse phenotypes, it is obvious that such cells should demonstrate substantial heterogeneity. Considerable research in this regard has indicated the presence of additional macrophage phenotypes that are exclusive to atherosclerotic plaques, namely Mox, M4, Mhem, and M(Hb) type. Furthermore, although the concept of macrophage clusters has come to the fore in recent years with the evolution of high-dimensional techniques, classifications based on such 'OMICS' approaches require extensive functional validation as well as metabolic phenotyping. Bearing this in mind, the current review provides an overview of the status of different macrophage populations and their role during atherosclerosis and also outlines possible therapeutic implications.

Annexin A2 (Anxa2), a multifunctional protein with RNA-binding capabilities, is frequently overexpressed in various tumors, and its expression is highly correlated with malignant progression. In this study, we demonstrate for the first time that Anxa2 was co-expressed with glycolytic genes, suggesting its potential role as a regulator of glycolysis. RNA-protein interaction assay revealed that Anxa2 interacted with 3'-UTR of H2AX mRNA and protected it from miRNA-mediated degradation. Up-regulated Histone-H2AX enhances the expression of glycolytic genes including GLUT1, HK2, PGK1, ENO1, PKM2, GAPDH and LDHA via stabilizing hypoxia-inducible factor 1-alpha (HIF1α), thereby accelerating lactic acid production and secretion. (20S) G-Rh2, a natural compound targeting Anxa2, significantly interfered the Anxa2-H2AX mRNA interaction, and inhibited subsequent glycolysis progression. We propose that Anxa2 acts as a novel regulator in glycolysis via enhancing H2AX expression, and (20S) G-Rh2 may exert its anti-cancer activity by targeting Anxa2-H2AX-HIF1α-glycolysis axis in human hepatoma HepG2 cells.

Obstructive sleep apnea (OSA) is a prevalent sleep disorder characterized by disrupted breathing patterns and dysfunctions in multiple organ systems. Although studies support a close correlation between OSA and immune function, the broader implications and specific manifestations remain unclear. Therefore, it is pressingly needed to identify potential immune-related markers and elucidate underlying immunological mechanisms of OSA. OSA-related datasets (GSE38792) and immune-related genes were downloaded from the GEO and ImmPort databases and intersected to obtain differentially expressed immune-related genes (DEIRGs). GO, KEGG, and GSEA were employed to explore the biological functions of DEIRGs. Immune cells and immune regulation were analyzed by CIBERSORT. The ROC curve was constructed to assess the accuracy of each DEIRG. The co-regulatory networks of transcription factors, microRNAs, and drugs were built using the NetworkAnalyst database and visualized by Cytoscape. The levels of DEIRGs in clinical samples were validated by RT-qPCR. GO, KEGG, and GSEA revealed that DEGs were mainly enriched in negative regulation of immune response and antigen processing and presentation in OSA. IL33, IL10RB, ANGPTL1, EIF2AK2, SEM1, IFNA16, SLC40A1, FCER1G, IL1R1, TNFRSF17, and ERAP2 were identified as DEIRGs among 175 differentially expressed genes in OSA. Memory B cells, mast cells resting, and dendritic cells resting were the predominant immune cells related to DEIRGs. The co-regulatory network contained 128 miRNAs, 40 transcription factors, and 172 drugs/compounds. Finally, IL33, EIF2AK2, IL10RB, and ANGPTL1 were also upregulated in clinical OSA samples. The present study identified potential immune-related biomarkers and systematically elucidated underlying immunological mechanisms of OSA. These findings provide novel insights into the diagnosis, mechanism research, and management strategies for future studies.

The prolyl-hydroxylase inhibitor (PHI), used effectively in several countries for the treatment of renal anemia, activates the multifunctional hypoxia-inducible factors (HIFs). While hypoxic conditions in tumors are known to affect the response to radiation therapy, the effect of PHI on the radiation response of cancer cells has not been determined. Hypoxic pretreatment increased the radiation sensitivity of A549 lung adenocarcinoma cells, whereas hypoxic culture after irradiation decreased the radiation sensitivity of HSC2 oral squamous cell carcinoma cells. Treatment of PC9 lung adenocarcinoma and HSC2 cells with the PHI FG-4592 significantly increased radiation resistance, whereas A549 and TIG3 lung fibroblast cells tended to be sensitized, suggesting cell type-specific differential effects of PHI. Quantitative RT-PCR analyses revealed that the basal and radiation-inducible expressions of DEC2, BAX, and BCL2 may be related to PHI-mediated radiation responses. Knock-down experiments showed that silencing of DEC2 sensitized both A549 and PC9 cells under PHI-treated conditions. On the other hand, silencing of p53, which regulates BAX/BCL2, desensitized A549 cells expressing wild-type p53, but not PC9 cells, with mutant-type p53, to irradiation, regardless of whether PHI was treated or not. Taken together, PHI modifies radiation responses in a cell type-specific manner, possibly through DEC2 signaling.

Severe acute hypoxic stress is a major contributor to the pathology of human diseases, including ischemic disorders. Current treatments focus on managing consequences of hypoxia, with few addressing cellular adaptation to low-oxygen environments. Here, we investigate whether accelerating hypoxia adaptation could provide a strategy to alleviate acute hypoxic stress. We develop a high-content phenotypic screening platform to identify compounds that fast-track adaptation to hypoxic stress. Our platform captures a high-dimensional phenotypic hypoxia response trajectory consisting of normoxic, acutely stressed, and chronically adapted cell states. Leveraging this trajectory, we identify compounds that phenotypically shift cells from the acutely stressed state towards the adapted state, revealing mTOR/PI3K or BET inhibition as strategies to induce this phenotypic shift. Importantly, our compound hits promote the survival of liver cells exposed to ischemia-like stress, and rescue cardiomyocytes from hypoxic stress. Our "phenopushing" platform offers a general, target-agnostic approach to identify compounds and targets that accelerate cellular adaptation, applicable across various stress conditions.

Hypoxia-inducible factors (HIFs) are key regulators of intracellular oxygen homeostasis. The marked increase in HIFs activity in hypoxia as compared to normoxia, together with their transcriptional control of primary metabolic pathways, motivated the widespread view of HIFs as responsible for the cell's metabolic adaptation to hypoxic stress. In this work, we suggest that this prevailing model of HIFs regulation is misleading. We propose an alternative model focused on understanding the dynamics of HIFs' activity within its physiological context. Our model suggests that HIFs would not respond to but rather prevent the onset of hypoxic stress by regulating the traffic of electrons between catabolic substrates and oxygen. The explanatory power of our approach is patent in its interpretation of the Warburg effect, the tendency of tumor cells to favor anaerobic metabolism over respiration, even in fully aerobic conditions. This puzzling behavior is currently considered as an anomalous metabolic deviation. Our model predicts the Warburg effect as the expected homeostatic response of tumor cells to the abnormal increase in metabolic demand that characterizes malignant phenotypes. This alternative perspective prompts a redefinition of HIFs' function and underscores the need to explicitly consider the cell's metabolic activity in understanding its responses to changes in oxygen availability.

Hypoxic stress causes cell damage and serious diseases in organisms, especially in aquatic animals. It is important to elucidate the changes in metabolic function caused by hypoxia and the mechanisms underlying these changes. This study focuses on the low oxygen tolerance feature of a new blunt snout bream strain (GBSBF1). Our data show that GBSBF1 has a different lipid and carbohydrate metabolism pattern than wild-type bream, with altering glycolysis and lipid synthesis. In GBSBF1, the expression levels of phd2 and vhl genes are significantly decreased, while the activation of HIF-3α protein is observed to have risen significantly. The results indicate that enhanced HIF-3α can positively regulate gpd1ab and gpam through PPAR-γ, which increases glucose metabolism and reduces lipolysis of GBSBF1. This research is beneficial for creating new aquaculture strains with low oxygen tolerance traits.

Adipose-derived stem cells (ADSCs) are known to promote angiogenesis and adipogenesis. However, their limited ability to efficiently target and integrate into specific tissues poses a major challenge for ADSC-based therapies. In this study, we identified a seven-amino acid peptide sequence (P7) with high specificity for ADSCs using phage display technology. P7 was then covalently conjugated to decellularized adipose-derived matrix (DAM), creating an "ADSC homing device" designed to recruit ADSCs both in vitro and in vivo. The P7-conjugated DAM significantly enhanced ADSC adhesion and proliferation in vitro. After being implanted into rat subcutaneous tissue, immunofluorescence staining after 14 days revealed that P7-conjugated DAM recruited a greater number of ADSCs, promoting angiogenesis and adipogenesis in the surrounding tissue. Moreover, CD206 immunostaining at 14 days indicated that P7-conjugated DAM facilitated the polarization of macrophages to the M2 phenotype at the implantation site. These findings demonstrate that the P7 peptide has a high affinity for ADSCs, and its conjugation with DAM significantly improves ADSC recruitment in vivo. This approach holds great potential for a wide range of applications in material surface modification.

Hypoxia is associated with the onset of cardiovascular diseases including cardiac hypertrophy and pulmonary hypertension. HIF2 (hypoxia inducible factor 2) signaling in the endothelium mediates pulmonary arterial remodeling and subsequent elevation of the right ventricular systolic pressure during chronic hypoxia. Thus, novel therapeutic opportunities for pulmonary hypertension based on specific HIF2 inhibitors have been proposed. Nevertheless, HIF2 relevance beyond the pulmonary endothelium or in the cardiac adaptation to hypoxia remains elusive. Wt1 (Wilms tumor 1) lineage contributes to the heart and lung vascular compartments, including pericytes, endothelial cells, and smooth muscle cells.

Here, we describe the response to chronic hypoxia of a novel HIF2 mutant mouse model in the Wt1 lineage (Hif2/Wt1 cKO [conditional knockout]), characterizing structural and functional aspects of the heart and lungs by means of classical histology, immunohistochemistry, flow cytometry, echocardiography, and lung ultrasound analysis.

Hif2/Wt1 cKO is protected against pulmonary remodeling and increased right ventricular systolic pressure induced by hypoxia, but displays alveolar congestion, inflammation, and hemorrhages associated with microvascular instability. Furthermore, lack of HIF2 in the Wt1 lineage leads to cardiomegaly, capillary remodeling, right and left ventricular hypertrophy, systolic dysfunction, and left ventricular dilation, suggesting pulmonary-independent cardiac direct roles of HIF2 in hypoxia. These structural defects are partially restored upon reoxygenation, while cardiac functional parameters remain altered.

Our results indicate that cardiopulmonary HIF2 signaling prevents excessive vascular proliferation during chronic hypoxia and define novel protective roles of HIF2 to warrant stable microvasculature and organ function.

Mammalian sirtuins are class III histone deacetylases involved in the regulation of multiple biological processes including senescence, DNA repair, apoptosis, proliferation, caloric restriction, and metabolism. Among the mammalian sirtuins, SIRT3, SIRT4, and SIRT5 are localized in the mitochondria and collectively termed the mitochondrial sirtuins. Mitochondrial sirtuins are NAD+-dependent deacetylases that play a central role in cellular metabolism and function as epigenetic regulators by performing post-translational modification of cellular proteins. Several studies have identified the role of mitochondrial sirtuins in age-related pathologies and the rewiring of cancer metabolism. Mitochondrial sirtuins regulate cellular functions by contributing to post-translational modifications, including deacetylation, ADP-ribosylation, demalonylation, and desuccinylation of diverse cellular proteins to maintain cellular homeostasis. Here, we review and discuss the structure and function of the mitochondrial sirtuins and their role as metabolic regulators in breast cancer. Altered breast cancer metabolism may promote tumor progression and has been an essential target for therapy. Further, we discuss the potential role of targeting mitochondrial sirtuin and its impact on breast cancer progression using sirtuin inhibitors and activators as anticancer agents.

Cancer is a heterogeneous disease, which contributes to its rapid progression and therapeutic failure. Besides interpatient tumor heterogeneity, tumors within a single patient can present with a heterogeneous mix of genetically and phenotypically distinct subclones. These unique subclones can significantly impact the traits of cancer. With the plasticity that intratumoral heterogeneity provides, cancers can easily adapt to changes in their microenvironment and therapeutic exposure. Indeed, tumor cells dynamically shift between a more differentiated, rapidly proliferating state with limited tumorigenic potential and a cancer stem cell (CSC)-like state that resembles undifferentiated cellular precursors and is associated with high tumorigenicity. In this context, CSCs are functionally located at the apex of the tumor hierarchy, contributing to the initiation, maintenance, and progression of tumors, as they also represent the subpopulation of tumor cells most resistant to conventional anti-cancer therapies. Although the CSC model is well established, it is constantly evolving and being reshaped by advancing knowledge on the roles of CSCs in different cancer types. Here, we review the current evidence of how CSCs play a pivotal role in providing the many traits of aggressive tumors while simultaneously evading immunosurveillance and anti-cancer therapy in several cancer types. We discuss the key traits and characteristics of CSCs to provide updated insights into CSC biology and highlight its implications for therapeutic development and improved treatment of aggressive cancers.

To assess the cardioprotective effect and impact of Qishen Granules (QSG) on different ischemic areas of the myocardium in heart failure (HF) rats by evaluating its metabolic pattern, substrate utilization, and mechanistic modulation.

In vivo, echocardiography and histology were used to assess rat cardiac function; positron emission tomography was performed to assess the abundance of glucose metabolism in the ischemic border and remote areas of the heart; fatty acid metabolism and ATP production levels were assessed by hematologic and biochemical analyses. The above experiments evaluated the cardioprotective effect of QSG on left anterior descending ligation-induced HF in rats and the mode of energy metabolism modulation. In vitro, a hypoxia-induced H9C2 model was established, mitochondrial damage was evaluated by flow cytometry, and nuclear translocation of hypoxia-inducible factor-1 α (HIF-1 α) was observed by immunofluorescence to assess the mechanism of energy metabolism regulation by QSG in hypoxic and normoxia conditions.

QSG regulated the pattern of glucose and fatty acid metabolism in the border and remote areas of the heart via the HIF-1 α pathway, and improved cardiac function in HF rats. Specifically, QSG promoted HIF-1 α expression and entry into the nucleus at high levels of hypoxia (P<0.05), thereby promoting increased compensatory glucose metabolism; while reducing nuclear accumulation of HIF-1 α at relatively low levels of hypoxia (P<0.05), promoting the increased lipid metabolism.

QSG regulates the protein stability of HIF-1 α, thereby coordinating energy supply balance between the ischemic border and remote areas of the myocardium. This alleviates the energy metabolism disorder caused by ischemic injury.

Cellular senescence and hypoxia-inducible factor (HIF) signaling are crucial in pulmonary aging and age-related lung diseases such as chronic obstructive pulmonary disease idiopathic pulmonary fibrosis and lung cancer. HIF plays a pivotal role in cellular adaptation to hypoxia, regulating processes like angiogenesis, metabolism, and inflammation. Meanwhile, cellular senescence leads to irreversible cell cycle arrest, triggering the senescence-associated secretory phenotype which contributes to chronic inflammation, tissue remodeling, and fibrosis. Dysregulation of these pathways accelerates lung aging and disease progression by promoting oxidative stress, mitochondrial dysfunction, and epigenetic alterations. Recent studies indicate that HIF and senescence interact at multiple levels, where HIF can both induce and suppress senescence, depending on cellular conditions. While transient HIF activation supports tissue repair and stress resistance, chronic dysregulation exacerbates pulmonary pathologies. Furthermore, emerging evidence suggests that targeting HIF and senescence pathways could offer new therapeutic strategies to mitigate age-related lung diseases. This review explores the intricate crosstalk between these mechanisms, shedding light on how their interplay influences pulmonary aging and disease progression. Additionally, we discuss potential interventions, including senolytic therapies and HIF modulators, that could enhance lung health and longevity.

Metabolic reprogramming in cancer cells involves changes in glucose metabolism, glutamine utilization, and lipid production, as well as promoting increased cell proliferation, survival, and immune resistance by altering the tumor microenvironment. Our study analyzes metabolic reprogramming in neoplastically transformed cells, focusing on changes in glucose metabolism, glutaminolysis, and lipid synthesis. Moreover, we discuss the therapeutic potential of targeting cancer metabolism, focusing on key enzymes involved in glycolysis, the pentose phosphate pathway, and amino acid metabolism, including lactate dehydrogenase A, hexokinase, phosphofructokinase and others. The review also highlights challenges such as metabolic heterogeneity, adaptability, and the need for personalized therapies to overcome resistance and minimize adverse effects in cancer treatment. This review underscores the significance of comprehending metabolic reprogramming in cancer cells to engineer targeted therapies, personalize treatment methodologies, and surmount challenges, including metabolic plasticity and therapeutic resistance.

Vascular endothelial cells are the predominant cell type in the cardiovascular system, and their dysfunction and death following hypoxic injury contribute to vascular lesions, playing an essential role in cardiovascular disease. Despite its importance, the mechanisms underlying vascular endothelial cell injury under hypoxia and potential therapeutic interventions remain poorly understood. Here, we constructed both an in vivo hypoxia model in C57BL/6 mice and an in vitro hypoxia model in HUVEC cells. Our findings demonstrated that hypoxia induces necroptosis in vascular endothelial cells and exacerbates inflammatory injury in vivo and in vitro, as evidenced by immunofluorescence and western blot. We identified FADD as a critical regulator of hypoxia-mediated necroptosis, with FADD knockdown significantly reversing hypoxia-induced necroptosis. Mechanistically, hypoxia affected protein conformation through SUMOylation of FADD and competitively inhibited its ubiquitination, leading to an increase in protein half-life and protein level of FADD. Furthermore, SUMOylation increased the interaction between FADD and RIPK1 and induced the formation of the FADD-RIPK1-RIPK3 complex, thereby promoting necroptosis in vascular endothelial cells. The SUMOylation inhibitor ginkgolic acid (GA) notably reduced hypoxia-induced vascular endothelial injury and inflammatory responses in male mice. Taken together, our research has uncovered a new process by which SUMOylation of FADD regulates hypoxia-induced necroptosis in endothelial cells, providing potential therapeutic targets for hypoxia-related cardiovascular diseases.

Tumor hypoxia is the major hindrance behind cancer chemotherapy and the foremost reason for the less effectiveness of most anticancer drugs. We herein inquire into the mechanistic part and therapeutic efficacy of our previously reported compound, aqua-(2-formylbenzoato) triphenyltin (IV) (abbreviated as OTC), in a hypoxic solid tumor-bearing mouse model (BALB/c). In addition to solid tumors, we investigated the therapeutic potential of OTC in intraperitoneal tumor and in in vitro system. Following treatment, mitochondrial dynamics, tumor load regression, survival analysis and histopathological parameters were analyzed. Furthermore, the differential expression levels of cleaved PARP-1, Hif-1α, VEGF and apoptotic genes such as Bax, Bcl-2, p53, and caspase 3 at the mRNA and protein levels were assessed. Our findings demonstrate that OTC significantly induces tumor regression and increased survivability by down regulating the expression of the hypoxia-associated genes Hif-1α and VEGF while elevating the levels of cleaved PARP-1 and p53. In contrast, the commercially available drug doxorubicin was found less effective and failed to respond in the tumor microenvironment. Furthermore, increased mitochondrial aggregation and membrane permeability and activation of Bax, caspase 3 and caspase-9 and release of Cytochrome-c from the mitochondrial membrane at RNA level confirms the mitochondrial pathway of apoptosis. Therefore, our present findings reveal that newly synthesized OTC potentially induces apoptosis and could be a promising compound against the tumor microenvironment.

Preeclampsia (PE) is a major cause of maternal mortality and morbidity, affecting 3-6% of pregnancies worldwide and ranking among the top six causes of maternal deaths in the U.S. PE typically develops after 20 weeks of gestation and is characterized by new-onset hypertension and/or end-organ dysfunction, with or without proteinuria. Current management strategies for PE emphasize early diagnosis, blood pressure control, and timely delivery. For prevention, low-dose aspirin (81 mg/day) is recommended for high-risk women between 12 and 28 weeks of gestation. Magnesium sulfate is also advised to prevent seizures in preeclamptic women at risk of eclampsia. Emerging management approaches include antiangiogenic therapies, hypoxia-inducible factor suppression, statins, and supplementation with CoQ10, nitric oxide, and hydrogen sulfide donors. Black women are at particularly high risk for PE, potentially due to higher rates of hypertension and cholesterol, compounded by healthcare disparities and possible genetic factors, such as the APOL1 gene. This review explores current and emerging strategies for managing PE and addresses the underlying causes of health disparities, offering potential solutions to improve outcomes.

Myocardial infarction (MI) is a severe hypoxic event, resulting in the loss of up to one billion cardiomyocytes (CMs). Due to the limited intrinsic regenerative capacity of the heart, cell-based regenerative therapies, which feature the implantation of stem cell-derived cardiomyocytes (SC-CMs) into the infarcted myocardium, are being developed with the goal of restoring lost muscle mass, re-engineering cardiac contractility, and preventing the progression of MI into heart failure (HF). However, such cell-based therapies are challenged by their susceptibility to oxidative stress in the ischemic environment of the infarcted heart. To maximize the therapeutic benefits of cell-based approaches, a better understanding of the heart environment at the cellular, tissue, and organ level throughout MI is imperative. This review provides a comprehensive summary of the cardiac pathophysiology occurring during and after MI, as well as how these changes define the cardiac environment to which cell-based cardiac regenerative therapies are delivered. This understanding is then leveraged to frame how cell culture treatments may be employed to enhance SC-CMs' hypoxia resistance. In this way, we synthesize both the complex experience of SC-CMs upon implantation and the engineering techniques that can be utilized to develop robust SC-CMs for the clinical translation of cell-based cardiac therapies.