bims-kishpe Biomed News
on HSP70 role in hypoxia and metabolism in ECs
Issue of 2025–01–12
thirty papers selected by
Alia Ablieh, Universität Heidelberg



  1. Exp Cell Res. 2025 Jan 07. pii: S0014-4827(25)00006-0. [Epub ahead of print]445(1): 114410
      Atherosclerosis (AS) is a chronic disease initiated by vascular endothelial dysfunction, with low shear stress (SS) being a critical inducing factor in this dysfunction. Apoptosis, a form of programmed cell death, is closely associated with AS progression. However, the impact of low SS on endothelial apoptosis and its specific molecular mechanisms remains unclear. Our study revealed that low SS induces apoptosis in endothelial cells and contributes to endothelial dysfunction. Under low SS conditions, miR-330 expression was markedly upregulated, which subsequently targeted and inhibited SOD2 expression, leading to ROS accumulation and oxidative stress. Overexpression of SOD2 under low SS conditions markedly elevated HSP70 expression, contributing to endothelial homeostasis. However, when HSP70 expression was inhibited in the context of SOD2 overexpression, there was a significant increase in pro-apoptotic proteins (BAX and cleaved-caspase-3) and total apoptosis rate, along with a significant reduction in endothelial function markers such as nitric oxide and endothelial nitric oxide synthase. Notably, our experiments indicated no direct interaction between SOD2 and HSP70. Furthermore, inhibiting ROS production significantly raised HSP70 expression, suggesting that SOD2 regulates HSP70 in an indirect process involving ROS. In summary, our findings elucidate that low SS induces endothelial apoptosis and dysfunction through the miR-330/SOD2/HSP70 signaling pathway, providing valuable insights into AS intervention and prevention.
    Keywords:  Apoptosis; HSP70; MicroRNA; Oxidative stress; Shear stress
    DOI:  https://doi.org/10.1016/j.yexcr.2025.114410
  2. Free Radic Biol Med. 2025 Jan 02. pii: S0891-5849(25)00001-2. [Epub ahead of print]228 163-172
      Mitochondria, commonly referred to as "energy factories"of cells, play a crucial role in the function and survival of cardiomyocytes. However, as research on cardiac fibrosis has advanced, mitochondrial dysfunction(including changes in energy metabolism, calcium ion imbalance, increased oxidative stress, and apoptosis)is now recognized as a significant pathophysiological pathway involved in cardiac remodeling and progression, which also negatively affects the function and structure of the heart. In recent years, research focusing on targeting mitochondria has gained significant attention, offering new approaches for treating cardiac fibrosis. Targeted mitochondrial therapy for cardiac fibrosis represents an emerging therapeutic strategy that aims to inhibit cardiac fibroblast proliferation or protect cardiomyocytes from damage by enhancing mitochondrial function. However, current research on epigenetic treatments for cardiac fibrosis through mitochondrial targeting remains limited. This review explores the relationship between mitochondrial dysfunction and cardiac fibrosis, as well as the epigenetic regulatory mechanisms involved in targeted mitochondrial therapy for cardiac fibrosis.
    Keywords:  Cardiac fibrosis; Epigenetic; Extracellular matrix; Fibroblasts; Mitochondrial
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2025.01.001
  3. Am J Physiol Lung Cell Mol Physiol. 2025 Jan 08.
      Lung endothelial cells (ECs) are essential for maintaining organ function and homeostasis. Despite sharing some common features with ECs from organ systems, lung ECs exhibit significant heterogeneity in morphology, function, and gene expression. This heterogeneity is increasingly recognized as a key contributor to the development of pulmonary diseases like pulmonary hypertension (PH). In this mini-review, we explore the evolving understanding of lung EC heterogeneity, particularly through the lens of single-cell RNA sequencing (scRNA-seq) technologies. These advances have provided unprecedented insights into the diverse EC subpopulations, their specific roles, and the disturbances in their homeostatic functions that contribute to PH pathogenesis. In particular, these studies identified novel and functionally distinct cell types such as aerocytes and general capillary ECs that are critical for maintaining lung function in health and disease. In addition, multiple novel pathways and mechanisms have been identified that contribute to aberrant pulmonary vascular remodeling in PH. Emerging techniques like single-nucleus RNA sequencing and spatial transcriptomics have further pushed the field forward by discovering novel disease mediators. As research continues to leverage these advanced techniques, the field is poised to uncover novel EC subtypes and disease mechanisms, paving the way for new therapeutic targets in PH and other lung diseases.
    Keywords:  angiogenesis; proliferation; pulmonary circulation; pulmonay hypertension; single cell RNA sequencing
    DOI:  https://doi.org/10.1152/ajplung.00296.2024
  4. Res Sq. 2024 Dec 24. pii: rs.3.rs-5690041. [Epub ahead of print]
      Glaucoma is a leading cause of irreversible blindness, often associated with elevated intraocular pressure (IOP) due to trabecular meshwork (TM) dysfunction. Diabetes mellitus (DM) is recognized as a significant risk factor for glaucoma; however, the molecular mechanisms through which hyperglycemia affects TM function remain unclear. This study investigated the impact of high glucose on gene expression in human TM (HTM) cells to uncover pathways that contribute to TM dysfunction and glaucoma pathogenesis under diabetic conditions. Primary HTM cells were cultured under normoglycemic (5.5 mM) and hyperglycemic (30 mM) conditions for seven days, followed by mRNA sequencing (mRNA-seq) to identify differentially expressed genes, with quantitative PCR (qPCR) used for confirmatory analysis. STRING network analysis was performed to predict interactions among upregulated and downregulated proteins. mRNA-seq analysis revealed 25 significantly differentially expressed genes in high glucose conditions, including upregulated genes associated with oxidative stress, apoptosis, autophagy, immune response, and fibrosis. Notably, TXNIP was significantly upregulated, indicating increased oxidative stress and apoptosis in TM cells, while downregulation of autophagy-related genes, such as HSPA6 and LAMP3, suggests compromised protein quality control. Immune response genes, including CCL7 and CHI3L1, were upregulated, suggesting an inflammatory response to oxidative stress. Increased expression of fibrosis-related genes, such as SNAI1, FGF7, and KRT19, supports the hypothesis of ECM accumulation in diabetic conditions, potentially elevating IOP. Chronic hyperglycemia in diabetic patients could therefore lead to TM dysfunction, impair aqueous humor outflow, and elevate IOP, thereby increasing glaucoma risk. Targeting oxidative stress and fibrosis pathways offers therapeutic strategies to mitigate glaucoma progression in diabetic populations.
    DOI:  https://doi.org/10.21203/rs.3.rs-5690041/v1
  5. Sci Rep. 2025 Jan 09. 15(1): 1530
      Glomerular endothelial cells (GECs) are pivotal in developing glomerular sclerosis disorders. The advancement of focal segmental glomerulosclerosis (FSGS) is intimately tied to disruptions in lipid metabolism. Sphingosine-1-phosphate (S1P), a molecule transported by high-density lipoproteins (HDL), exhibits protective effects on vascular endothelial cells by upregulating phosphorylated endothelial nitric oxide synthase (p-eNOS) and enhancing nitric oxide (NO) production. Nevertheless, the abundance of S1P within HDL in individuals with FSGS and minimal change disease (MCD) is yet to be elucidated, and its defensive role in GECs necessitates empirical confirmation. A total of 14 FSGS patients, 16 MCD patients, and 16 healthy controls (NC) were included in the study, with FSGS and MCD confirmed by renal biopsy. After blood sample collection, HDL was isolated and categorized into intact HDL, phospholipid-depleted HDL(apo-HDL), phospholipid-remained HDL(phoHDL), and recombinant HDL (rHDL). Various HDL samples, comprising intact, apo-HDL, pho-HDL and rHDL, were co-cultivated with human renal glomerular endothelial cells (HRGECs). Western blotting was utilized to quantify p-eNOS levels and assess PI3K-AKT pathway activation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyzed S1P concentrations, while real-time quantitative PCR evaluated the expression of enzymes involved in S1P metabolism. Fluorescence labeling methods measured NO levels, and an immunofluorescence colocalization assay investigated Sphingosine-1-phosphate receptor 1 (S1PR1) expression in GECs across distinct kidney tissue groups. The HDL from FSGS patients demonstrated a significantly enhanced ability to promote p-eNOS expression and NO release in HRGECs compared to MCD patients and healthy controls. Additionally, the synthesis activity of S1P in renal tissues of FSGS patients was markedly higher than that observed in MCD patients and healthy controls, suggesting that S1P may play a crucial protective role in the progression of FSGS. Immunofluorescence staining showed that compared with MCD and NC, the expression of S1PR1 in GECs of FSGS patients was significantly decreased. Recombinant HDL with added S1P promoted the increase of p-eNOS in HRGECs. Knockdown of S1PR1 using siRNA reduced the expression of p-eNOS and NO release. The mechanism underlying the regulation of p-eNOS expression by rHDL was associated with the PI3K-AKT signaling pathway. The enhanced presence of S1P on HDL could serve as a diagnostic marker to differentiate FSGS from MCD. Incorporating S1P into HDL enhances glomerular endothelial cell function, suggesting that the S1P/S1PR pathway might offer a promising therapeutic avenue for FSGS.
    Keywords:  Focal segmental glomerulosclerosis; Glomerular endothelial cells; High-density lipoprotein; Minimal change disease; Sphingosine-1-phosphate
    DOI:  https://doi.org/10.1038/s41598-025-85865-8
  6. Front Immunol. 2024 ;15 1503087
      Acute pancreatitis (AP) is an inflammatory disease of the pancreas and a complex process involving multiple factors, with mitochondrial damage playing a crucial role. Mitochondrial dysfunction is now considered a key driver in the development of AP. This dysfunction often presents as increased oxidative stress, altered membrane potential and permeability, and mitochondrial DNA damage and mutations. Under stress conditions, mitochondrial dynamics and mitochondrial ROS production increase, leading to decreased mitochondrial membrane potential, imbalanced calcium homeostasis, and activation of the mitochondrial permeability transition pore. The release of mitochondrial DNA (mtDNA), recognized as damage-associated molecular patterns, can activate the cGAS-STING1 and NF-κB pathway and induce pro-inflammatory factor expression. Additionally, mtDNA can activate inflammasomes, leading to interleukin release and subsequent tissue damage and inflammation. This review summarizes the relationship between mitochondria and AP and explores mitochondrial protective strategies in the diagnosis and treatment of this disease. Future research on the treatment of acute pancreatitis can benefit from exploring promising avenues such as antioxidants, mitochondrial inhibitors, and new therapies that target mitochondrial dysfunction.
    Keywords:  acute pancreatitis; calcium overload; mitochondrial; mitochondrial permeability transition pore; regulated cell death
    DOI:  https://doi.org/10.3389/fimmu.2024.1503087
  7. Cells. 2024 Dec 12. pii: 2055. [Epub ahead of print]13(24):
      The endothelium is a well known regulator of vascular homeostasis. Several factors can influence the balance of the bioavailability of active substances. This imbalance can lead to inflammation and, consequently, endothelial dysfunction, which is an underlying pathology in cardiovascular disease that commonly coexists with metabolic and chronic diseases such as metabolic dysfunction-associated steatotic liver disease (MASLD). In MASLD, a reduction in nitric oxide availability is observed, and as a result, hepatic stellate cells and liver sinusoidal endothelial cells are activated. Considering the extensive research dedicated to finding several targets with diagnostic and therapeutic effects, nuclear hormone receptors such as peroxisome proliferator-activated receptors have been highlighted as being highly influential in the gut-liver-adipose axis and are considered potential regulators of metabolism and inflammation in several pathologies. Currently, PPAR agonists are widely explored in clinical trials and experimental studies. Agents such as lanifibranor, elafibranor, daidzein, and Icariin have shown promise in improving the metabolic, hepatic, and cardiovascular health of patients with MASLD. This review aims to provide a comprehensive overview of the role of peroxisome proliferator-activated receptors in endothelial dysfunction and MASLD, exploring their mechanisms in disease progression and potential pharmacological targeting.
    Keywords:  MASLD; PPAR; endothelial dysfunction; inflammation; liver; pharmacological targeting
    DOI:  https://doi.org/10.3390/cells13242055
  8. Sci Rep. 2025 Jan 07. 15(1): 1113
      In oxygen-deprived conditions, cells respond by activating adaptive mechanisms to bolster their survival and protect tissue integrity. A key player in this process is the HIF-1α signaling cascade, meticulously regulated by Prolyl Hydroxylase Domain 2 (PHD2), which orchestrates cellular responses to varying oxygen levels. The primary aim of this investigation is to utilize gut siderophores as inhibitors of PHD2 in ischemic conditions. This study also helps in understanding the structural mechanisms by which gut microbiota regulate HIF-1α via PHD2 inhibition through the secretion of siderophores. We explore potential PHD2 inhibitors through in-silico approaches, specifically molecular docking, binding pose metadynamics, molecular dynamics simulations, and free energy calculations. We evaluated siderophores secreted by gut microbiota as candidate inhibitors for PHD2. Docking studies revealed that Salmochelin SX exhibits the highest binding affinity to PHD2 (- 9.527 kcal/mol), interacting with key residues such as ASP254, TYR310, ASP315, and ARG322. Despite its high affinity, binding pose metadynamics indicated instability for Salmochelin SX, whereas Staphyloferrin A demonstrated superior stability. Molecular dynamics simulations confirmed stable ligand interactions with PHD2, highlighting HIS313 and ASP315 as critical for inhibition. Principal Component Analysis (PCA) and Free Energy Landscape (FEL) analyses underscored conformational changes and binding stability, suggesting that these interactions may stabilize PHD2's active site and have potential therapeutic implications. Additionally, the study reveals how gut microbiota prevent gut dysbiosis through the stabilization of HIF-1α signaling by secreting siderophores.
    Keywords:  Gut microbiota; HIF-1α signaling; Hypoxia; Ischemia; Siderophores
    DOI:  https://doi.org/10.1038/s41598-024-83730-8
  9. Int J Mol Sci. 2024 Dec 15. pii: 13448. [Epub ahead of print]25(24):
      The pathogenesis of neurodegenerative diseases results from the interplay between genetic and environmental factors. Aging and chronic oxidative stress are critical contributors to neurodegeneration. UBQLN2, a ubiquitin-related protein, aids in protein degradation and protects against oxidative stress. In ALS neurons harboring UBQLN2 mutations, oxidative stress accelerates pathological changes, yet the precise mechanisms remain unclear. Using induced motor neurons (iMNs) derived from UBQLN2 P497H iPSCs, we observed ALS-like phenotypes, including TDP-43 mislocalization, increased cell death, and reduced viability. Sodium arsenite (SA)-induced oxidative stress triggered stress granule formation, while autophagy dysfunction exacerbated neuronal degeneration. CHX and bosutinib treatments reduced ubiquitinated protein accumulation and alleviated degeneration, highlighting potential therapeutic pathways. These findings emphasize the role of chronic oxidative stress and stress granule formation in UBQLN2 ALS, offering insights into novel therapeutic targets.
    Keywords:  ALS; UBQLN2; motor neurons; neurodegenerative diseases; oxidative stress; stress granule
    DOI:  https://doi.org/10.3390/ijms252413448
  10. Cells. 2024 Dec 30. pii: 29. [Epub ahead of print]14(1):
      Hypoxia-inducible factors (HIFs) are central regulators of gene expression in response to oxygen deprivation, a common feature in critical illnesses. The significant burden that critical illnesses place on global healthcare systems highlights the need for a deeper understanding of underlying mechanisms and the development of innovative treatment strategies. Among critical illnesses, impaired lung function is frequently linked to hypoxic conditions. This review focuses on the expression and regulation of HIF signalling in experimental models of acute lung injury (ALI) and clinical studies in critically ill patients with acute respiratory distress syndrome (ARDS). We explore the potential dual role of HIF signalling in acute lung inflammation. Furthermore, its role in key biological processes and its potential prognostic significance in clinical scenarios are discussed. Finally, we explore recent pharmacological advancements targeting HIF signalling, which have emerged as promising alternatives to existing therapeutic approaches, potentially enabling more effective management strategies.
    Keywords:  ARDS; HIF; acute lung injury; hypoxia
    DOI:  https://doi.org/10.3390/cells14010029
  11. BMC Cardiovasc Disord. 2025 Jan 06. 25(1): 7
       BACKGROUND: The dried root of Inula helenium L., known as Inulae Radix in Mongolian medicine, is a widely used heat-clearing plant drug within the Asteraceae family. Alantolactone (ATL), a compound derived from Inulae Radix, is a sesquiterpene lactone with a range of biological activities. However, there is a lack of studies investigating its effectiveness in the treatment of hypertension. The aim of this study is to explore the regulatory effect of alantolactone on blood pressure and its underlying mechanism.
    METHODS AND RESULTS: Network pharmacology analysis suggested that ATL had a potential therapeutic effect on hypertension induced by angiotensin II (Ang II). Subsequently, the results of animal experiments demonstrated that ATL could suppress the increase in blood pressure caused by Ang II. Vascular ring experiments indicated that ATL could inhibit the vascular contractions induced by Ang II, Phenylephrine, and Ca2⁺. Further experiments demonstrated that ATL could inhibit the calcium influx induced by Ang II and increase the expression of pMLC2. Molecular docking experiments showed that ATL had a high binding affinity with L-type Voltage-gated Calcium Channels (VGCC), and vascular ring experiments indicated that ATL could significantly inhibit the vascular contractions caused by the agonists of L-type VGCC. In addition, we also observed that ATL had an ameliorative effect on the vascular remodeling induced by Ang II.
    CONCLUSIONS: ATL exerted an antihypertensive effect by inhibiting the activation of L-type VGCC and reducing calcium influx.
    Keywords:   Calcium influx; Alantolactone; Hypertension; Voltage-gated Calcium Channels
    DOI:  https://doi.org/10.1186/s12872-024-04461-2
  12. Cells. 2024 Dec 22. pii: 2125. [Epub ahead of print]13(24):
      Tissue acidification resulting from dysregulated cellular bioenergetics accompanies various inflammatory states. GPR68, along with other members of proton-sensing G protein-coupled receptors, responds to extracellular acidification and has been implicated in chronic inflammation-related diseases such as ischemia, cancer, and colitis. The present study examined the role of extracellular acidification on human pulmonary endothelial cell (EC) permeability and inflammatory status per se and investigated potential synergistic effects of acidosis on endothelial dysfunction caused by bacterial lipopolysaccharide (LPS, Klebsiella pneumoniae). Results showed that medium acidification to pH 6.5 caused a delayed increase in EC permeability illustrated by a decrease in transendothelial electrical resistance and loss of continuous VE-cadherin immunostaining at cell junctions. Likewise, acidic pH induced endothelial inflammation reflected by increased mRNA and protein expression of EC adhesion molecules VCAM-1 and ICAM-1, upregulated mRNA transcripts of tumor necrosis factor-α, IL-6, IL-8, IL-1β, and CXCL5, and increased secretion of ICAM-1, IL-6, and IL-8 in culture medium monitored by ELISA. Among the GPCRs tested, acidic pH selectively increased mRNA and protein expression of GPR68, and only the GPR68-specific small molecule inhibitor OGM-8345 rescued acidosis-induced endothelial permeability and inflammation. Furthermore, acidic pH exacerbated LPS-induced endothelial permeability and inflammatory response in cultured lung macrovascular as well as microvascular endothelial cells. These effects were suppressed by OGM-8345 in both EC types. Altogether, these results suggest that GPR68 is a critical mediator of acidic pH-induced dysfunction of human pulmonary vascular endothelial cells and mediates the augmenting effect of tissue acidification on LPS-induced endothelial cell injury.
    Keywords:  GPR4; GPR68; LPS; OGM-8345; acidosis; endothelial permeability; inflammation
    DOI:  https://doi.org/10.3390/cells13242125
  13. Physiol Rep. 2025 Jan;13(1): e70193
      Inflammation and a metabolic shift from oxidative metabolism to glycolysis are common in the ischemic heart, the latter partly controlled by pyruvate kinase (muscle, PKM). We previously identified alternative splicing promoting the PKM2 isoform after myocardial infarction (MI). We examined the role of PKM2 physiological upregulation after MI, modeled by ligation of the left anterior descending coronary artery, using global PKM2 knockout (PKM2-/-) mice. Echocardiography showed similar cardiac function between PKM2-/- and control mice after MI. However, PKM2-/- infarcted hearts had increased abundances of transcripts associated with oxidative stress and immune responses. Immunohistochemistry revealed greater abundance of macrophages in PKM2-/- hearts prior to MI, with a small increase in CD86+ macrophages in PKM2-/- infarcted hearts. Elevated baseline plasma IL-6, IL-1β, and C-reactive protein, and cardiac IL-6, 3 days post-MI, were observed in PKM2-/- mice. Oxidative lipid products were also elevated in baseline PKM2-/- hearts, while antioxidant glutathione peroxidase 4 was reduced. Greater fibrosis was seen in PKM2-/- hearts 28 days after MI. These findings suggest Pkm2 ablation primes the heart for increased oxidative stress, inflammation, and fibrosis post-MI. The natural upregulation of PKM2 may mitigate fibrosis by reducing oxidative stress and inflammation, highlighting its protective role in the infarcted heart.
    Keywords:  fibrosis; inflammation; myocardial infarction; oxidative stress
    DOI:  https://doi.org/10.14814/phy2.70193
  14. Int J Mol Med. 2025 Mar;pii: 45. [Epub ahead of print]55(3):
      Retinal pigment epithelial (RPE) cells undergoing epithelial‑mesenchymal transition (EMT) are a key factor in promoting the progression of subretinal fibrosis. The klotho protein and gene exert anti‑fibrotic effects in multiple fibrotic diseases. However, the mechanisms involved in the role of klotho are unclear in subretinal fibrosis. The aim of the present study was to explore the effects of klotho on subretinal fibrosis induced by laser photocoagulation in mice and EMT induced by TGF‑β1 in RPE cells and the underlying molecular mechanisms. In vitro, klotho overexpression or knockdown was performed in ARPE‑19 cells (adult retinal Pigment Epithelial‑19), then TGF‑β1 treatment was applied. Using western blotting, expression of epithelial markers (zonula occludens‑1), mesenchymal signs (α‑smooth muscle actin, α‑SMA, N‑cadherin, N‑cad and collagen I), and the ERK1/2 and Wnt/β‑catenin signaling pathways were assessed. The proliferative ability of ARPE‑19 cells was examined by CCK‑8 and EdU test, and the migratory ability was examined by wound healing and Transwell assays. Furthermore, to explore the underlying molecular pathway of klotho overexpression, RNA‑sequencing (seq) was performed. In vivo, photocoagulation was used to induce subretinal fibrosis in mice, which occurs as a result of choroidal neovascularization (CNV), then recombinant mouse klotho protein was administered intravitreally. Upregulation of epithelial and downregulation of mesenchymal markers demonstrated that klotho overexpression prevented TGF‑β1‑induced EMT; klotho knockdown resulted in the opposite effects. Additionally, klotho overexpression suppressed cell proliferation and migration and attenuated ERK1/2 and Wnt/β‑catenin signaling activated by TGF‑β1. RNA‑seq results demonstrated that several signaling pathways, including cellular senescence and the TNF signaling pathway, were associated with anti‑fibrotic effects of klotho overexpression. In vivo, subretinal fibrotic areas were attenuated following klotho treatment in laser‑induced CNV lesions, as illustrated by immunofluorescence and Masson staining of the mouse eyes. Western blotting results that the protein levels of mesenchymal markers were significantly downregulated and those of epithelial markers were upregulated. In summary, the present study suggested that klotho may have therapeutic value in management of fibrotic vitreoretinal disorders such as subretinal fibrosis.
    Keywords:  age‑related macular degeneration; choroidal neovascularization; klotho; retinal pigment epithelium; subretinal fibrosis
    DOI:  https://doi.org/10.3892/ijmm.2025.5486
  15. PLoS One. 2025 ;20(1): e0317110
       BACKGROUND: Systemic diseases are often associated with endothelial cell (EC) dysfunction. A key function of ECs is to maintain the barrier between the blood and the interstitial space. The integrity of the endothelial cell barrier is maintained by VE-Cadherin homophilic interactions between adjacent cells. The morphology of these borders is highly dynamic and can be actively remodeled by numerous drivers in a (patho)physiologic context specific fashion.
    OBJECTIVES: High-content screening of the impact of circulatory factors on the morphology of VE-Cadherin borders in endothelial monolayers in vitro will enable the assessment of the progression of systemic vascular disease. We therefore aimed to create an image analysis pipeline, capable of automatically analyzing images from large scale screenings, both capturing all VE-cadherin phenotypes present in a sample while preserving the higher-level 2D structure. Our pipeline is aimed at creating 1D tensor representations of the VE-cadherin adherence junction structure and negate the need for normalization.
    METHOD: An image analysis pipeline, with at the center a convolution neural network was developed. The deep neural network was trained using examples of distinct VE-Cadherin morphologies from many experiments. The generalizability of the model was extensively tested in independent experiments, before further validation using ECs exposed ex vivo to plasma from patients with liver cirrhosis and proven vascular complications.
    RESULTS: Our workflow was able to detect and stratify many of the different VE-Cadherin morphologies present within the datasets and produced similar results within independent experiments, proving the generality of the model. Finally, by EC-cell border morphology profiling, our pipeline enabled the stratification of liver cirrhosis patients and associated patient-specific morphological cell border changes to responses elicited by known inflammatory factors.
    CONCLUSION: We developed an image analysis pipeline, capable of intuitively and robustly stratifying all VE-Cadherin morphologies within a sample. Subsequent VE-Cadherin morphological profiles can be used to compare between stimuli, small molecule screenings, or assess disease progression.
    DOI:  https://doi.org/10.1371/journal.pone.0317110
  16. bioRxiv. 2024 Dec 17. pii: 2024.12.13.628451. [Epub ahead of print]
      The integrity of the hematopoietic stem cell (HSC) pool relies on efficient long-term self-renewal and the timely removal of damaged or differentiation-prone HSCs. Previous studies have demonstrated the PERK branch of the unfolded protein response (UPR) drives specific programmed cell death programs to maintain HSC pool integrity in response to ER stress. However, the role of PERK in regulating HSC fate in vivo remains unclear. Here, we demonstrate that PERK is dispensable for normal hematopoiesis and HSC self-renewal under steady-state conditions. In contrast, PERK is activated to promote HSC proliferation and depletion in response to ER stress induced by the inactivation of ER-associated degradation (ERAD), via the knockout of key components of ERAD Sel1L or Hrd1. Inhibition of PERK, either through genetic knockout or knock-in of a point mutation that eliminates PERK kinase activity, significantly restores the HSC defects induced by Sel1L or Hrd1 knockout. Mechanistic studies reveal that ERAD deficiency does not lead to HSC death or ROS accumulation. Instead, PERK promotes the activation of mTOR signaling and drives abnormal proliferation of HSCs, impairing their self-renewal potential. This process removes stressed HSCs, thereby maintaining HSC pool integrity. Our study uncovers a PERK-centered strategy employed by HSCs to preserve their pool integrity independently of apoptosis.
    Key points: PERK is not required for steady-state hematopoiesis but preserves hematopoietic stem cell pool integrity in response to increased ER stress.Under ER stress induced by ERAD deficiency, PERK is activated to promote mTOR signaling and HSC hyper-proliferation, depleting damaged HSCs.
    DOI:  https://doi.org/10.1101/2024.12.13.628451
  17. Sci Rep. 2025 Jan 09. 15(1): 1487
      The mechanisms underlying exercise-induced insulin sensitization are of great interest, as exercise is a clinically critical intervention for diabetic patients. Some microRNAs (miRs) are secreted from skeletal muscle after exercise where they regulate insulin sensitivity, and have potential as diagnostic markers in diabetic patients. miR-204 is well-known for its involvement in development, cancer, and metabolism; however, its role in exercise-induced glycemic control remains unclear. In the present study, endurance exercise in mice increased miR-204 expression levels in skeletal muscle. In a chronic exercise model, miR-204 expression levels were elevated along with glycolytic enzymes in skeletal muscle. When muscular hypoxia was induced after exercise, miR-204 expression also increased with the upregulation of hypoxia-inducible factor 1-alpha (HIF-1α). Furthermore, HIF-1α overexpression led to increased miR-204 expression. Treatment with a miR-204 mimic in C2C12 cells significantly enhanced the glycolysis rate and the mRNA expression of glycolytic enzymes. Notably, intravenous administration of miR-204 in mice increased the glucose clearance rate following refeeding. miR-204 initially elevated blood glucose levels at an early stage of refeeding but later promoted blood glucose reduction as refeeding continued. Additionally, glycolytic enzymes were upregulated in the skeletal muscles of miR-204-injected mice. These findings suggest a novel physiological role for miR-204 in promoting skeletal muscle glycolysis, particularly in situations where insulin action is limited.
    Keywords:  Diabetes; Exercise; Glycolysis; miR-204; miRNA
    DOI:  https://doi.org/10.1038/s41598-025-85174-0
  18. Nitric Oxide. 2025 Jan 07. pii: S1089-8603(25)00002-3. [Epub ahead of print]
      COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), primarily manifests as a flu-like illness with lung injury, often necessitating supplemental oxygen. Elderly individuals and those with pre-existing cardiovascular diseases are at increased risk of mortality. The endothelial barrier disruption observed in patients indicates systemic viral invasion and widespread endotheliitis. Endothelial dysfunction, characterized by impaired nitric oxide (NO) production, contributes to vasoconstriction, inflammation, and coagulation abnormalities seen in COVID-19. In this study, we investigated the impact of COVID-19 patient-derived plasma on the endothelium through NO metabolite analysis using an in vitro 3D micro vessel model. Our experiments revealed alterations in NO metabolites in response to COVID-19 patient plasma perfusion, with BH4+BH2 supplementation improving citrulline levels in severe COVID-19 patient models. Positive correlation between arginase activity and eNOS activity was observed in the severe COVID-19 patient model but not in the mild COVID-19 patient model. These findings underscore the importance of endothelial dysfunction in COVID-19 pathogenesis and highlight potential therapeutic targets for mitigating vascular complications associated with severe infection.
    Keywords:  3D microvessels-on-chip model; Arginase; Biopterin; COVID-19; Endothelial Nitric Oxide Synthase; Endothelial dysfunction; Nitric Oxide
    DOI:  https://doi.org/10.1016/j.niox.2025.01.002
  19. Curr Rev Clin Exp Pharmacol. 2024 Dec 30.
      Pulmonary hypertension (PH) is a severe, progressive disorder characterized by elevated pulmonary arterial pressure, leading to right ventricular failure and increased mortality. Despite advancements in management, the median survival for PH patients remains 5-7 years, with an inhospital mortality rate of approximately 6%. The core pathological feature of PH is pulmonary vascular remodeling (PVR), a multifactorial process involving endothelial dysfunction, inflammation, and aberrant immune responses. While current therapies target endothelial dysfunction, they fall short of preventing PVR or halting disease progression. Emerging research highlights the potential of immune-inflammatory pathways, oxygen-sensing mechanisms, and gut microbiota modulation as therapeutic targets. Integrating nutritional strategies, probiotics, and fecal microbiota transplantation (FMT) as adjunctive therapies also shows promise. These factors may collectively influence PVR, offering novel insights into therapeutic avenues for PH management in the future.
    Keywords:  Chemokines; heart disease; hypertension; inflammation; microbiota.
    DOI:  https://doi.org/10.2174/0127724328325178241210174545
  20. Sci Rep. 2025 Jan 06. 15(1): 915
      Preeclampsia (PE) is a prevalent and severe pregnancy complication that significantly impacts maternal and perinatal health. Epidemiological studies and animal experiments have demonstrated that PE adversely affects the cardiovascular and nervous systems of offspring, increasing their risk of hypertension and renal pathology. However, the mechanisms underlying this increased risk remain unclear. This study utilized an L-NAME-induced preeclampsia mouse model (PELS model) to investigate the effects of PE on offspring blood pressure and renal pathology, focusing on the expression of Angiotensin II Type 1 Receptors (AT1R) and related molecules in renal tissues. Our findings show that L-NAME-induced pre-eclampsia led to reduced birth weights and significantly elevated systolic blood pressure in 6-week-old offspring. Histopathological analysis revealed pronounced glomerular and tubular damage in the kidneys of both 1-week and 6-week-old offspring from the pre-eclampsia group. At 1 week of age, the pre-eclampsia group exhibited elevated mRNA and protein expression levels of AT1R, GRK4, AQP2, ENaC, and NCC in renal tissues compared to controls. However, these differences were no longer significant at 6 weeks of age. No significant gender differences were observed in either blood pressure or renal pathological changes. Preeclampsia induced by L-NAME results in increased blood pressure and renal damage in offspring, potentially mediated by early alterations in the renal RAS system. The observed changes in AT1R and related molecules appear to be transient, suggesting that the early impact of pre-eclampsia on renal structure may trigger, but not sustain, hypertension in offspring. Further studies are needed to elucidate the long-term mechanisms driving hypertension in this population.
    DOI:  https://doi.org/10.1038/s41598-025-85258-x
  21. Cells. 2024 Dec 18. pii: 2091. [Epub ahead of print]13(24):
       BACKGROUND: Vascular calcification (VC) is a dynamic, tightly regulated process driven by cellular activity and resembling the mechanisms of bone formation, with specific molecules playing pivotal roles in its progression. We aimed to investigate the involvement of the bone morphogenic proteins (BMP-2, BMP-4, BMPR-1a/1b, and BMPR-2) system in this process. Our study used an advanced in vitro model that simulates the biological environment of the vascular wall, assessing the ability of a phosphate mixture to induce the osteoblastic switch in human coronary artery smooth muscle cells (HCASMCs).
    METHODS: HCASMCs were grown in mono- and co-culture with human coronary artery endothelial cells (HCAECs) in a double-flow bioreactor (LiveBox2 and IVTech), allowing static and dynamic conditions through a peristaltic pump. The VC was stimulated by incubation in a calcifying medium for 7 days. A BMP system Real-Time PCR was performed at the end of each experiment.
    RESULTS: In monocultures, BMP-2 expression increased in calcified HCASMCs in static (p = 0.01) and dynamic conditions. BMP-4 and the biological receptors were expressed in all the experimental settings, increasing mainly in dynamic flow conditions. In co-cultures, we observed a marked increase in BMP-2 and BMP-4, BMPR-1a (p = 0.04 and p = 0.01, respectively), and BMPR-2 (p = 0.001) in the calcifying setting mostly in dynamic conditions.
    CONCLUSIONS: The increase in BMP-2/4 in co-culture suggests that these genes might promote the switch towards an osteogenic-like phenotype, data also supported by the rise of both BMPR-1a and BMPR-2. Thus, our findings provide insights into the mechanisms by which dynamic co-culture modulates the BMP system activation in an environment mimicking in vivo VC's cellular and mechanical characteristics.
    Keywords:  BMP system; calcification; endothelial cells; vascular smooth muscle cells
    DOI:  https://doi.org/10.3390/cells13242091
  22. Int J Mol Sci. 2024 Dec 11. pii: 13275. [Epub ahead of print]25(24):
      Endothelial cells (ECs) are crucial for vascular health, regulating blood flow, nutrient exchange, and modulating immune responses and inflammation. The impairment of these processes causes the endothelial dysfunction (ED) characterized by oxidative stress, inflammation, vascular permeability, and extracellular matrix remodeling. While primary ECs have been widely used to study ED in vitro, their limitations-such as short lifespan and donor variability-pose challenges. In this context, induced iECs derived from induced pluripotent stem cells offer an innovative solution, providing an unlimited source of ECs to explore disease-specific features of ED. Recent advancements in 3D models and microfluidic systems have enhanced the physiological relevance of iEC-based models by better mimicking the vascular microenvironment. These innovations bridge the gap between understanding ED mechanisms and drug developing and screening to prevent or treat ED. This review highlights the current state of iEC technology as a model to study ED in vascular and non-vascular disorders, including diabetes, cardiovascular, and neurodegenerative diseases.
    Keywords:  cardiovascular diseases; diabetes; endothelial cells; endothelial dysfunction; induced pluripotent stem cells; neurodegenerative disorders
    DOI:  https://doi.org/10.3390/ijms252413275
  23. Nat Cell Biol. 2025 Jan 08.
      Errors during cell division lead to aneuploidy, which is associated with genomic instability and cell transformation. In response to aneuploidy, cells activate the tumour suppressor p53 to elicit a surveillance mechanism that halts proliferation and promotes senescence. The molecular sensors that trigger this checkpoint are unclear. Here, using a tunable system of chromosome mis-segregation, we show that mitotic errors trigger nuclear deformation, nuclear softening, and lamin and heterochromatin alterations, leading to rapid p53/p21 activation upon mitotic exit in response to changes in nuclear mechanics. We identify mTORC2 and ATR as nuclear deformation sensors upstream of p53/p21 activation. While triggering mitotic arrest, the chromosome mis-segregation-induced alterations of nuclear envelope mechanics provide a fitness advantage for aneuploid cells by promoting nuclear deformation resilience and enhancing pro-invasive capabilities. Collectively, this work identifies a nuclear mechanical checkpoint triggered by altered chromatin organization that probably plays a critical role in cellular transformation and cancer progression.
    DOI:  https://doi.org/10.1038/s41556-024-01565-x
  24. Acta Cardiol. 2025 Jan 09. 1-13
       OBJECTIVE: Elevated systolic blood pressure and increased pulse pressure are closely associated with renal damage; however, the exact mechanism remains unclear. Therefore, we investigated the effects of increased pulse pressure on tubulointerstitial fibrosis and renal damage in elderly rats with isolated systolic hypertension (ISH). Additionally, the role of renal tubular epithelial-mesenchymal transition (EMT) and its upstream signalling pathways were elucidated.
    METHODS: Ten-month-old male rats were randomly divided into control and ISH groups, with seven rats in each group administered warfarin and vitamin K1 for 6 weeks. Blood pressure, renal function, mean blood flow in the common iliac artery, and diastolic vessel diameter were assessed, and the rat kidney medulla was collected for histological, genetic, and protein level analysis.
    RESULTS: Increased pulse pressure, abnormal renal function, and increased shear stress were detected in rats with ISH. Histology assessments revealed fibrosis in the interstitium of ISH rats. Epithelial marker E-cadherin protein expression was decreased, while the protein expression of interstitial markers α-SMA and Vimentin was increased, and transforming growth factor (TGF)-β1/Smad3 signalling was upregulated in the kidney tissue of ISH rats.
    CONCLUSIONS: Increased pulse pressure in elderly rats with ISH caused an increase in shear stress. These effects led to the development of EMT and the activation of its upstream TGF-β1/Smad3 signalling pathway, ultimately leading to renal tubular interstitial fibrosis causing renal injury.
    Keywords:  Isolated systolic hypertension; epithelial-mesenchymal transformation; pulse pressure; renal interstitial fibrosis; shear stress
    DOI:  https://doi.org/10.1080/00015385.2024.2445339
  25. Arch Biochem Biophys. 2025 Jan 06. pii: S0003-9861(25)00003-7. [Epub ahead of print]764 110290
       BACKGROUND AND AIMS: Vascular smooth muscle cells are pivotal in atherosclerosis, transitioning from a contractile to a synthetic phenotype, which is associated with increased proliferation and inflammation. FRZB, a Wnt signaling modulator, has been implicated in vascular pathology, but its specific role in vascular smooth muscle cell phenotype modulation is not well understood. This study investigates the role of FRZB in regulating vascular smooth muscle cell phenotypes.
    METHODS: Vascular smooth muscle cell regions were categorized based on FRZB expression levels, and various analyses, including differential gene expression, KEGG pathway analysis, and Disease Ontology analysis, were conducted. FRZB knockdown in human aortic vascular smooth muscle cell was performed using siRNA, followed by assessments of cell migration, proliferation, and phenotype marker expression.
    RESULTS: FRZB expression was significantly reduced in synthetic type compared to contractile type in both mouse models and human samples. FRZB knockdown in human vascular smooth muscle cells led to increased cell migration and proliferation, alongside decreased expression of contractile markers and increased synthetic markers. Unexpectedly, FRZB knockdown suppressed Wnt signaling. Pathway analysis revealed associations with the PI3K-Akt signaling pathway, focal adhesion, and ECM interactions.
    CONCLUSIONS: Our study highlights FRZB's role in Vascular smooth muscle cell phenotype modulation, showing that reduced FRZB expression correlates with a synthetic phenotype and increased disease markers. FRZB does not enhance Wnt signaling but may regulate vascular smooth muscle cell behavior through alternative pathways. These findings suggest FRZB as a potential therapeutic target for stabilizing vascular smooth muscle cells and managing atherosclerosis.
    Keywords:  Atherosclerosis; Focal adhesion; Frizzled-related protein; Phenotype modulation; Vascular smooth muscle cell
    DOI:  https://doi.org/10.1016/j.abb.2025.110290
  26. Nat Rev Genet. 2025 Jan 09.
      Traditionally, differences among individuals have been divided into genetic and environmental causes. However, both types of variation can underlie regulatory changes in gene expression - that is, epigenetic changes - that persist across cell divisions (developmental differentiation) and even across generations (transgenerational inheritance). Increasingly, epigenetic variation among individuals is recognized as an important factor in human diseases and ageing. Moreover, non-genetic inheritance can lead to evolutionary changes within populations that differ from those expected by genetic inheritance alone. Despite its importance, causally linking epigenetic variation to phenotypic differences across individuals has proven difficult, particularly when epigenetic variation operates independently of genetic variation. New genomic approaches are providing unprecedented opportunity to measure and perturb epigenetic variation, helping to elucidate the role of epigenetic variation in mediating the genotype-phenotype map. Here, we review studies that have advanced our understanding of how epigenetic variation contributes to phenotypic differences between individuals within and across generations, and provide a unifying framework that allows historical and mechanistic perspectives to more fully inform one another.
    DOI:  https://doi.org/10.1038/s41576-024-00804-z
  27. Nat Commun. 2025 Jan 09. 16(1): 515
      After a peripheral nerve injury, Schwann cells (SCs), the myelinating glia of the peripheral nervous system, convert into repair cells that foster axonal regrowth, and then remyelinate or re-ensheath regenerated axons, thereby ensuring functional recovery. The efficiency of this mechanism depends however on the time needed for axons to regrow. Here, we show that ablation of histone deacetylase 8 (HDAC8) in SCs accelerates the regrowth of sensory axons and sensory function recovery. We found that HDAC8 is specifically expressed in sensory SCs and regulates the E3 ubiquitin ligase TRAF7, which destabilizes hypoxia-inducible factor 1-alpha (HIF1α) and counteracts the phosphorylation and upregulation of c-Jun, a major inducer of the repair SC phenotype. Our study indicates that this phenotype switch is regulated by different mechanisms in sensory and motor SCs and is accelerated by HDAC8 downregulation, which promotes sensory axon regeneration and sensory function recovery.
    DOI:  https://doi.org/10.1038/s41467-025-55835-9
  28. Sci Rep. 2025 Jan 06. 15(1): 925
      Estrogen sulfotransferase (SULT1E1), a member of the sulfotransferase family (SULTs), is the enzyme with the strongest affinity for estrogen. Despite significant associations between SULT1E1 and the progression and prognosis of a range of diseases, its functional role and potential mechanisms in lung adenocarcinoma (LUAD) remain unclear. The objective of this study was to examine the potential of SULT1E1 as a biomarker for LUAD. The molecular characteristics, disease relevance and expression levels of SULT1E1 in different cancers were analysed using public databases. GEPIA 2, Starbase and other databases were employed to analyse the expression levels of SULT1E1 in LUAD tissues and normal lung tissues, and to investigate the correlation with clinical stages. A prognostic analysis was conducted using the KM database and the tumour database. The SULT1E1 protein interaction network was constructed using the STRING database. The LUAD dataset from TCGA was employed for the purposes of performing functional enrichment and immune infiltration analyses. Subsequently, the expression levels of SULT1E1 in LUAD cell lines, human LUAD tissues and normal tissues were detected by Western blot and other methods. The expression of SULT1E1 was further detected by immunohistochemical staining, and the correlation between the expression level of SULT1E1 and the clinical characteristics and prognosis of LUAD patients was verified. The expression of SULT1E1 in cytoplasm and nucleus was detected by cellular immunofluorescence. Significant reductions in SULT1E1 expression were observed across various tissues and cell lines of LUAD, as supported by both bioinformatics and Western blotting analyses. Analysis of gene ontology suggested that SULT1E1 potentially exerts anticarcinogenic effects by modulating protein serine/threonine kinase activity and its associated pathway. Additionally, KEGG and GSEA analyses indicated SULT1E1's involvement in drug metabolism, choline metabolism in cancer, hormone synthesis, and other relevant pathways. Examination of immune infiltration demonstrated a strong correlation between SULT1E1 expression and the presence of immune cells such as TAM and Treg. Furthermore, SULT1E1 expression levels in LUAD were found to correlate with TNM stage, histological stage, platelet count to lymphocyte count ratio (PLR), neutrophil count to lymphocyte count ratio (NLR), and systemic immune-inflammation index (SII). Low SULT1E1 expression levels were significantly associated with shorter overall survival (OS) in LUAD patients. The suppression of lung adenocarcinoma (LUAD) by SULT1E1 makes it a potential biomarker for diagnosing and predicting the prognosis of LUAD.
    Keywords:  Bioinformatics analysis; Biological function; Biomarker; Lung adenocaroma; Prognosis; SULT1E1
    DOI:  https://doi.org/10.1038/s41598-024-82129-9
  29. iScience. 2025 Jan 17. 28(1): 111516
      Ischemia and pathological angiogenesis in retinal vascular diseases cause serious vision-related problems. However, the transcriptional regulators of vascular repair remain unidentified. Thus, the factors and mechanisms involved in angiogenesis must be elucidated to develop approaches for restoring normal blood vessels. Here, we investigated the effects of the stress response activating transcription factor 3 (ATF3) on angiogenesis and vascular regeneration in vitro and in vivo. ATF3 was expressed specifically in retinal vascular endothelial cells (ECs) during vascular development. Vascular endothelial growth factor stimulation upregulated ATF3 expression in cultured ECs. The downregulated ATF3 expression in ECs caused the deterioration of vascular network formation in vitro and in vivo. Moreover, ATF3 deletion in a model of oxygen-induced retinopathy inhibited retinal vascular repair but not pathological neovascularization. Transcriptome analysis confirmed that high ATF3 expression upregulated the expression of angiogenesis-related genes in ECs. ATF3 may aid vascular repair therapy in retinal vascular diseases.
    Keywords:  Ophthalmology; Transcriptomics; Vascular remodeling
    DOI:  https://doi.org/10.1016/j.isci.2024.111516
  30. FASEB J. 2025 Jan 15. 39(1): e70283
      Molecular chaperones play critical roles in post-translational maintenance in protein homeostasis. Previous studies have shown that loss of Smyd1b function results in defective myofibril organization and dramatic upregulation of heat shock protein gene (hsp) expression in muscle cells of zebrafish embryos. To investigate the molecular mechanisms and functional importance of this stress response, we characterized changes of gene expression in smyd1b knockdown and knockout embryos using RNA-seq. The results showed that the top upregulated genes encode mostly cytosolic heat shock proteins. Co-IP assay revealed that the upregulated cytosolic Hsp70s associate with myosin chaperone UNC45b which is critical for myosin protein folding and sarcomere assembly. Strikingly, several hsp70 genes also display muscle-specific upregulation in response to heat shock-induced stress in zebrafish embryos. To investigate the regulation of hsp gene upregulation and its functional significance in muscle cells, we generated heat shock factor 1 (hsf-/-) knockout zebrafish mutants and analyzed hsp gene expression and muscle phenotype in the smyd1b-/-single and hsf1-/-;smyd1b-/- double-mutant embryos. The results showed that knockout of hsf1 blocked the hsp gene upregulation and worsened the muscle defects in smyd1b-/- mutant embryos. Moreover, we demonstrated that Hsf1 is essential for fish survival under heat shock (HS) conditions. Together, these studies uncover a correlation between Smyd1b deficiency and the Hsf1-activated heat shock response (HSR) in regulating muscle protein homeostasis and myofibril assembly and demonstrate that the Hsf1-mediated hsp gene upregulation is vital for the survival of zebrafish larvae under thermal stress conditions.
    Keywords:  Smyd1b; heat shock factor 1; heat shock protein; myofibril; stress response
    DOI:  https://doi.org/10.1096/fj.202401875R