The Role of HO-1 and Its Crosstalk with Oxidative Stress in Cancer Cell Survival

Targeting PTGDS Promotes ferroptosis in peripheral T cell lymphoma through regulating HMOX1-mediated iron metabolism

BACKGROUND

Peripheral T cell lymphoma (PTCL) is characterized by high heterogeneity, strong aggressiveness, and extremely poor prognosis. Ferroptosis, a novel form of programmed cell death, has been involved in tumor development and targeting ferroptosis holds great potential for tumor therapy.

METHODS

Lentiviral transfection was performed to regulate gene expression, followed by Tandem mass tag (TMT)-mass spectrometry and RNA-sequencing. Tumor xenograft models were established for in vivo experiments.

RESULTS

High expression of prostaglandin D2 synthase (PTGDS) was closely associated with poor prognosis of PTCL patients. PTGDS knockdown and AT56 treatment significantly inhibited the progression of PTCL through regulating cell viability, proliferation, apoptosis, cell cycle and invasion in vitro and in vivo. We further revealed that targeting PTGDS promoted ferroptosis process and enhanced the sensitivity of PTCL cells to ferroptosis inducers Sorafenib in vitro and in vivo. Mechanically, PTGDS interacted with heme-degrading enzymes HMOX1, and targeting PTGDS increased the level of iron and induced ferroptosis in PTCL through promoting HMOX1-mediated heme catabolism and ferritin autophagy process. Through the construction of H25A mutation, the specific gene site of HMOX1 corresponding to its role was identified.

CONCLUSIONS

Taken together, our findings firstly identified that targeting PTGDS promotes the ferroptosis in PTCL through regulating HMOX1-mediated iron metabolism, and highlighted novel therapeutic strategies to improve the efficacy of ferroptosis-targeted therapy in PTCL patients.

Scutellaria barbata D.Don and Hedyotis diffusa Willd herb pair combined with cisplatin synergistically inhibits ovarian cancer progression through modulating oxidative stress via NRF2-FTH1 autophagic degradation pathway

BACKGROUND

Cisplatin (DDP) is one of the most effective anticancer drugs, commonly used to treat advanced ovarian cancer (OC). However, DDP has significant limitations of platinum-based drugs, including chemical resistance and high-dose toxic side effects. Traditional Chinese medicines (TCMs) often presented in the form of formula, in which the herb pair was the basic unit. Scutellaria barbata D.Don and Hedyotis diffusa Willd (SB-HD) are famous TCMs herb pair that have been shown to help treat multiple types of cancers. However, the synergistic effects and mechanism of combination of SB-HD and DDP to enhance DDP chemosensitivity in OC are still unknown.

RESULTS

In vitro, we found that the optimal proportion of SB-HD to inhibit the proliferation of OC cells was 2:1, SB-HD and DDP were shown to synergistically reduce the viability of OC cells, inhibit the colony formation, promote cell cycle arrest and apoptosis, as well as inhibit cell migration and invasion. In vivo, combination treatment significantly inhibited the growth of subcutaneous tumors in BALB/c nude mice and reduced the toxic side effects of DDP. Mechanistically, SB-HD and DDP combination treatment significantly promoted oxidative stress response, decreased MMP, inhibited ATP production, decreased ROS levels and increased SOD activity, increased the expression of NRF2, HO-1, ATG5 and LC3, decreased the expression of p62 and FTH1 both in OC cells and tumor tissue of mice. Inhibitor 3-MA (Methyladenine, autophagy inhibitor) and Fer-1 (Ferrostatin-1, iron ion inhibitor) can effectively reverse the expression changes of the key target proteins, but not ZnPP (Zinc protoporphyrin, HO-1 inhibitor). Through bioinformatics analysis, it was found that the abnormal expression level of NRF2 and FTH1 mRNA has a high prognostic value, at the same time, the other four key proteins respectively or interacting with NRF2 and FTH1, also play important roles in the occurrence and development of OC.

CONCLUSION

Our findings uncover a synergistic effect of SB-HD and DDP against OC through modulating oxidative stress via NRF2-FTH1 autophagic degradation pathway, which may provide an important theoretical foundation for the use of SB-HD and a new strategy for enhancing DDP chemosensitivity as well as reducing toxic side effects.

Copper complexes induce haem oxygenase-1 (HMOX1) and cause apoptotic cell death in pancreatic cancer cells

Pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic malignancy, has a dismal 5-year survival rate, making palliative chemotherapy the only treatment option. Targeted therapy has limited efficacy in PDAC, underscoring the need for novel therapeutic approaches. The inducible stress-response protein, haem oxygenase-1 (HMOX1), has been implicated in treatment failure in PDAC. Copper coordination complexes have shown promise as anticancer agents against various cancers, and are associated with apoptotic cell death. The different ligands to which copper is complexed, determine the specificity and efficacy of each complex. Three different classes of copper complexes were evaluated for anti-cancer activity against AsPC-1 and MIA PaCa-2 pancreatic cancer cell lines. A copper-phenanthroline-theophylline complex (CuPhTh2), a copper-8-aminoquinoline-naphthyl complex (Cu8AqN), and two copper-aromatic-isoindoline complexes (CuAIsI) were effective inhibitors of cell proliferation with clinically relevant IC50 values below 5 μM. The copper complexes caused reactive oxygen species (ROS) formation, promoted annexin-V binding, disrupted the mitochondrial membrane potential (MMP) and activated caspase-9 and caspase-3/7, confirming apoptotic cell death. Expression of nuclear HMOX1 was increased in both cell lines, with the CuPhTh2 complex being the most active. Inhibition of HMOX1 activity significantly decreased the IC50 values of these copper complexes suggesting that HMOX1 inhibition may alter treatment outcomes in PDAC.

Dental pulp stem cells derived exosomes inhibit ferroptosis via regulating the Nrf2-keap1/GPX4 signaling pathway to ameliorate chronic kidney disease injury

INTRODUCTION

Chronic kidney disease (CKD) has long represented a substantial global health challenge. Regrettably, current therapeutic interventions exhibit limited efficacy in halting the progression of CKD. Ferroptosis may play a crucial role in CKD, as indicated by substantial evidence. Dental pulp stem cell-derived exosomes (DPSC-Exos) possess advantages such as abundant sources and low immunogenicity, holding promising prospects in CKD treatment.

METHODS

This study constructed a mouse CKD model to investigate the therapeutic effects of DPSC-Exos. First, we successfully extracted and identified DPSC-Exos. Then, mice were randomly divided into sham, PBS, CKD, and CKD+Exos groups. Our study determined the expression of ferroptosis-related pathway molecules Nrf2, GPX4, Keap1, and HO-1 in each group. Finally, we detected the expression levels of inflammatory factors, TNF-α, IL-1β, and IL-6, at the injury site.

RESULTS

Mice treated with DPSC-Exos showed increased expression of the ferroptosis inhibitory factor Nrf2 and its downstream regulatory factors GPX4 and HO-1, while the expression of Keap1 decreased. The expression of TNF-α, IL-1β, and IL-6 also decreased.

CONCLUSION

DPSC-Exos may help inhibit ferroptosis through the Keap1-Nrf2/GPX4 pathway and reduce the inflammatory response at the injury site, revealing their potential therapeutic effects on CKD.

α-Tocopherol Long-Chain Metabolite α-T-13'-COOH Exhibits Biphasic Effects on Cell Viability, Induces ROS-Dependent DNA Damage, and Modulates Redox Status in Murine RAW264.7 Macrophages

SCOPE

The α-tocopherol long-chain metabolite α-tocopherol-13'-hydroxy-chromanol (α-T-13'-COOH) is a proposed regulatory intermediate of endogenous vitamin E metabolism. Effects of α-T-13'-COOH on cell viability and adaptive stress response are not well understood. The present study aims to investigate the concentration-dependent effects of α-T-13'-COOH on cellular redox homeostasis, genotoxicity, and cytotoxicity in murine RAW264.7 macrophages as a model system.

METHODS AND RESULTS

Murine RAW264.7 macrophages are exposed to various dosages of α-T-13'-COOH to determine its regulatory effects on reactive oxygen species (ROS) production, DNA damage, expression of stress-related markers, and the activity of ROS scavenging enzymes including superoxide dismutases, catalase, and glutathione-S-transferases. The impact on cell viability is assessed by analyzing cell proliferation, cell cycle arrest, and cell apoptosis.

CONCLUSION

α-T-13'-COOH influences ROS production and induces DNA damage in a dose-dependent manner. The metabolite modulates the activity of ROS-scavenging enzymes, with significant changes observed in the activities of antioxidant enzymes. A biphasic response affecting cell viability is noted: sub-micromolar doses of α-T-13'-COOH promote cell proliferation and enhance DNA synthesis, whereas supraphysiological doses lead to DNA damage and cytotoxicity. It hypothesizes an adaptive stress response, characterized by upregulation of ROS detoxification mechanisms, enhanced cell cycle arrest, and increased apoptosis, indicating a correlation with oxidative stress and subsequent cellular damage.

Cytoglobin attenuates melanoma malignancy but protects melanoma cells from ferroptosis

Cutaneous malignant melanoma is the most aggressive and the deadliest form of skin cancer. There are two types of limitations which universally exist in current melanoma therapy: Adverse effects and reduced efficiency. Cytoglobin (CYGB), an iron hexacoordinated globin, is highly enriched in melanocytes and frequently epigenetically silenced during melanoma genesis. The present study aimed to explore its potential role as a biomarker for ferroptosis treatment. It was observed that B16F10 and A375 melanoma cells with loss of CYGB expression were highly sensitive to ferroptosis inducers RSL3 and erastin, whereas G361 melanoma cells with highly enriched CYGB were resistant to RSL3 or erastin. Ectopically overexpressed CYGB rendered B16F10 and A375 cells resistant to RSL3 or erastin, accompanied by decreased proliferation and epithelial‑mesenchymal transition (EMT). By contrast, knockdown of CYGB expression made G361 cells sensitive to ferroptosis induction but induced proliferation and EMT progression of G361 cells. Mechanistically, CYGB‑induced resistance of melanoma cells to ferroptosis may have been associated, in part, with i) Suppression of EMT; ii) upregulation of glutathione peroxidase 4 expression; iii) decrease of labile iron pool. In vivo study also demonstrated that CYGB overexpression rendered xenograft melanoma much more resist to RSL3 treatment. Based on these findings, CYGB is a potential therapeutic biomarker to screen the melanoma patients who are most likely benefit from ferroptosis treatment.

Navigating the redox landscape: reactive oxygen species in regulation of cell cycle

Objectives: To advance our knowledge of disease mechanisms and therapeutic options, understanding cell cycle regulation is critical. Recent research has highlighted the importance of reactive oxygen species (ROS) in cell cycle regulation. Although excessive ROS levels can lead to age-related pathologies, ROS also play an essential role in normal cellular functions. Many cell cycle regulatory proteins are affected by their redox status, but the precise mechanisms and conditions under which ROS promote or inhibit cell proliferation are not fully understood.Methods: This review presents data from the scientific literature and publicly available databases on changes in redox state during the cell cycle and their effects on key regulatory proteins.Results: We identified redox-sensitive targets within the cell cycle machinery and analysed different effects of ROS (type, concentration, duration of exposure) on cell cycle phases. For example, moderate levels of ROS can promote cell proliferation by activating signalling pathways involved in cell cycle progression, whereas excessive ROS levels can induce DNA damage and trigger cell cycle arrest or cell death.Discussion: Our findings encourage future research focused on identifying redox-sensitive targets in the cell cycle machinery, potentially leading to new treatments for diseases with dysregulated cell proliferation.

Sodium formate induces development-dependent intestinal epithelial injury via necroptosis and apoptosis

OBJECTIVES

Necrotizing enterocolitis (NEC) is a common and sometimes fatal disease affecting premature infants. Elevated formate has been found in the stool of patients with NEC. Sodium formate (NaF) is used to explore the role of formate in the intestinal epithelial injury.

METHODS

In this study, 150 mM NaF solution was intraluminally injected in 14-day-old and 28-day-old mice. Mice were sacrificed after 24 h of feces collection, and the blood and small intestinal tissues were collected to detect the pathological damage of intestinal tissue, intestinal permeability, oxidative stress indicators including SOD, HO-1, MDA, and 4-HNE, inflammatory cytokines including IL-1β, TNF-α and IL-6, mitochondrial function such as ATP and PGC-1α in mice intestinal tissue, indicators of the cell death modes including necroptosis-related protein RIPK1 and p-MLKL, and apoptosis- related protein cleaved-caspase-3 and p-AKT (S473).

RESULTS

NaF treatment significantly damaged intestinal epithelial tissue and barrier function, caused mitochondrial dysfunction, manifesting as decreased ATP and PGC-1α levels, increased lipid peroxidation products MDA and 4-HNE, depleted antioxidant enzyme SOD, and upregulated the expression of HO-1. Furthermore, NaF treatment induced inflammatory responses by promoting the release of IL-1β, IL-6 and TNF-α in a development-dependent manner, eventually inducing necroptosis and apoptosis.

CONCLUSIONS

Formate may be a source of metabolic intestinal injury contributing to the pathogenesis of NEC in human newborns.

The Multifaceted Role of Bilirubin in Liver Disease: A Literature Review

Bilirubin, the primary breakdown product of hemoproteins, particularly hemoglobin, plays a key role in the diagnosis, prognosis, and monitoring of liver diseases. In acute liver diseases, such as acute liver failure, drug-induced liver injury, and viral hepatitis, bilirubin serves as a biomarker reflecting the extent of hepatocyte loss and liver damage. Chronic liver diseases, including alcohol-related liver disease, chronic hepatitis C virus infection, metabolic dysfunction-associated fatty liver disease, and autoimmune liver diseases, are marked by persistent liver injury and inflammation. Bilirubin levels in chronic liver diseases provide insight into liver function, disease severity, and prognosis. As a versatile biomarker, bilirubin offers valuable information on the pathophysiology of liver diseases and aids in guiding clinical decision-making regarding the treatment of liver diseases and their complications. This review aimed to explore the multifunctional role of bilirubin in liver diseases by analyzing its biological functions beyond its role as a biomarker of liver damage.

Hydroethanolic Extract of Polygonum aviculare L. Mediates the Anti-Inflammatory Activity in RAW 264.7 Murine Macrophages Through Induction of Heme Oxygenase-1 and Inhibition of Inducible Nitric Oxide Synthase

Polygonum aviculare L. (PAL), commonly known as knotgrass, has been utilized as a traditional folk medicine across Asian, African, Latin American and Middle Eastern countries to treat various inflammatory diseases, including arthritis and airway inflammation. Numerous medicinal herbs exert anti-inflammatory and antioxidative effects that are mediated through the activation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and the inhibition of nuclear factor kappa B (NF-κB). However, the underlying molecular mechanisms linking the antioxidative and anti-inflammatory effects remain poorly understood. Heme oxygenase-1 (HO-1) is an antioxidant enzyme that catalyzes heme degradation, ultimately leading to the production of carbon monoxide (CO). Elevated levels of CO have been correlated with the decreased level of inducible nitric oxide synthase (iNOS). In this study, we examined whether HO-1 plays a key role in the relationship between the antioxidative and anti-inflammatory properties of PAL. The anti-inflammatory and antioxidative activities of PAL in an in vitro system were evaluated by determining NF-κB activity, antioxidant response element (ARE) activity, pro-inflammatory cytokine and protein levels, as well as antioxidant protein levels. To examine whether HO-1 inhibition interfered with the anti-inflammatory effect of PAL, we measured nitrite, reactive oxygen species, iNOS, and HO-1 levels in RAW 264.7 murine macrophages pre-treated with Tin protoporphyrin (SnPP, an HO-1 inhibitor). Our results demonstrated that PAL increased ARE activity and the Nrf2-regulated HO-1 level, exerting antioxidative activities in RAW 264.7 macrophages. Additionally, PAL reduced cyclooxygenase-2 (COX-2) and iNOS protein levels by inactivating NF-κB in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Further investigation using the HO-1 inhibitor revealed that HO-1 inhibition promoted iNOS expression, subsequently elevating nitric oxide (NO) generation in LPS-activated RAW 264.7 macrophages treated with PAL compared to those in the macrophages without the HO-1 inhibitor. Overall, our findings suggest that HO-1 induction by PAL may exert anti-inflammatory effects through the reduction of the iNOS protein level. Hence, this study paves the way for further investigation to understand molecular mechanisms underlying the antioxidative and anti-inflammatory activities of medicinal herbs.

25-Hydroxycholecalciferol Improves Cardiac Metabolic Adaption, Mitochondrial Biogenetics, and Redox Status to Ameliorate Pathological Remodeling and Functional Failure in Obese Chickens

Broiler breeder hens allowed ad libitum (Ad) feed intake developed obesity and cardiac pathogenesis and thereby were susceptible to sudden death. A supplement of 69 µg 25-hydroxycholecalciferol (25-OH-D3)/kg feed rescued the livability of feed-restricted (R) and Ad-hens (mortality; 6.7% vs. 8.9% and 31.1% vs. 48.9%). Necropsy with the surviving counterparts along the time course confirmed alleviation of myocardial remodeling and functional failure by 25-OH-D3, as shown by BNP and MHC-β expressions, pathological hypertrophy, and cardiorespiratory responses (p < 0.05). 25-OH-D3 mitigated cardiac deficient bioenergetics in Ad-hens by rescuing PGC-1α activation, mitochondrial biogenesis, dynamics, and electron transport chain complex activities, and metabolic adaptions in glucose oxidation, pyruvate/lactate interconversion, TCA cycle, and β-oxidation, as well as in TG and ceramide accumulation to limit lipotoxic development (p < 0.05). Supplemental 25-OH-D3 also sustained Nrf2 activation and relieved MDA accumulation, protein carbonylation, and GSH depletion to potentiate cell survival in the failing heart (p < 0.05). Parts of the redox amendments were mediated via lessened blood hematocrit and heme metabolism, and improved iron status and related gene regulations (p < 0.05). In conclusion, 25-OH-D3 ameliorates cardiac pathological remodeling and functional compromise to rescue the livability of obese hens through metabolic flexibility and mitochondrial bioenergetics, and by operating at antioxidant defense, and heme and iron metabolism, to maintain redox homeostasis and sustain cell viability.

Maintaining KEAP1 levels in retinal pigment epithelial cells preserves their viability during prolonged exposure to artificial blue light

Exposure to artificial blue light, one of the most energetic forms of visible light, can increase oxidative stress in retinal cells, potentially enhancing the risk of macular degeneration. Retinal pigment epithelial (RPE) cells play a crucial role in this process; the loss of RPE cells is the primary pathway through which retinal degeneration occurs. In RPE cells, Kelch-like ECH-associated protein 1 (KEAP1) is located in both the nucleus and cytosol, where it binds to nuclear factor erythroid 2-related factor 2 (NRF2) and p62 (sequestosome-1), respectively. Blue light exposure activates the NRF2-heme oxygenase 1 (HMOX1) axis through both canonical and noncanonical p62 pathways thereby reducing oxidative damage, and initiates autophagy, which helps remove damaged proteins. These protective responses may support the survival of RPE cells. However, extended exposure to blue light drastically decreases the viability of RPE cells. This exposure diminishes the ability of KEAP1 to bind to p62 and reduces the level of KEAP1. Inhibition of autophagy does not prevent KEAP1 degradation, the NRF2-HMOX1 axis, or blue-light-induced cytotoxicity. However, proteasome inhibitor along with a transient increase in the amount of KEAP1 in RPE cells, partially restores the p62-KEAP1 complex and reduces blue-light-induced cytotoxicity. In vivo studies confirmed the downregulation of KEAP1 in damaged RPE cells. Mice subjected to periodic blue light exposure exhibited significant atrophy in the outer retina, particularly in the peripheral areas. Additionally, there was a significant decrease in c-wave electroretinography and pupillary light reflex, indicating functional impairments in both visual and nonvisual physiological processes. These data underscore the essential role of KEAP1 in managing oxidative defense and autophagy pathways triggered by blue light exposure in RPE cells.

The Role of Oxidative Stress and DNA Hydroxymethylation in the Pathogenesis of Benzo[a]pyrene-Impaired Reproductive Function in Male Mice

Benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon, is known to cause teratogenesis. Environmental exposure of BaP has led to wide public concerns due to their potential risk of reproductive toxicity. However, the exact mechanism is still not clear. We aimed to explore the alterations of oxidative stress and DNA hydroxymethylation during BaP-impaired reproductive function. BALB/c mice were intragastrically administered with different doses of BaP (0.01, 0.1, and 1 mg/kg/day, once a day), while control mice were administered with corn coil. Then, the reproductive function, alterations of oxidative stress, DNA methylation, and DNA hydroxymethylation of testis tissues were evaluated. We found that BaP caused obvious histopathological damages of testis tissues. As for sperm parameters after BaP administration, testis weight and the rate of teratosperm were increased, as well as sperm count and motility were decreased. In mechanism, BaP upregulated HO-1 and MDA levels and downregulated SOD and CAT activity and GSH content in testis tissues, indicating that oxidative stress was induced by BaP. Furthermore, a significant induction of hydroxymethylation and inhibition of methylation were observed in testis tissues after BaP exposure. Collectively, BaP-induced oxidative stress and hydroxymethylation were involved in impairing reproductive function, which may be the mechanism of the male infertility.

Cu-Doping Layered Double Hydroxides Nanozyme Integrated with Nitric Oxide Donor for Enhanced Antioxidant Therapy in Retinopathy

The prevalence of retinal neovascular diseases necessitates novel treatments beyond current therapies like laser surgery or anti-VEGF treatments, which often carry significant side effects. A novel therapeutic approach is introduced using copper-containing layered double hydroxides (Cu-LDH) nanozymes integrated with nitric oxide-releasing molecules (GSHNO), forming Cu-LDH@GSHNO aimed at combating oxidative stress within the retinal vascular system. Combination of synthetic chemistry and biological testing, Cu-LDH@GSHNO are synthesized, characterized, and assessed for curative effect in HUVECs and an oxygen-induced retinopathy (OIR) mouse model. The results indicate that Cu-LDH@GSHNO demonstrates SOD-CAT cascade catalytic ability, accompanied with GSH and nitric oxide-releasing capabilities, which significantly reduces oxidative cell damage and restores vascular function, presenting a dual-function strategy that enhances treatment efficacy and safety for retinal vascular diseases. The findings encourage further development and clinical exploration of nanozyme-based therapies, promising a new horizon in therapeutic approaches for managing retinal diseases driven by oxidative stress.

Transcriptome and RNA sequencing analysis of H9C2 cells exposed to diesel particulate matter

Although air pollution has been classified as a risk factor for heart disease, the underlying mechanisms remain nebulous. Therefore, this study investigated the effect of diesel particulate matter (DPM) exposure on cardiomyocytes and identified differentially expressed genes (DEGs) induced by DPM. DPM treatment decreased H9C2 cell viability and increased cytotoxicity. Ten genes showed statistically significant differential expression following treatment with DPM at 25 and 100 μg/ml for 3 h. A total of 273 genes showed statistically significant differential expression following treatment with DPM at 25 and 100 μg/ml for 24 h. Signaling pathway analysis revealed that the DEGs were related to the 'reactive oxygens species,' 'IL-17,' and 'fluid shear stress and atherosclerosis' signaling pathways. Hmox1, Fos, and Fosb genes were significantly upregulated among the selected DEGs. This study identified DPM-induced DEGs and verified the selected genes using qRT-PCR and western blotting. The findings provide insights into the molecular events in cardiomyocytes following exposure to DPM.

A novel role for WZ3146 in the inhibition of cell proliferation via ERK and AKT pathway in the rare EGFR G719X mutant cells

Mutations in the epidermal growth factor receptor (EGFR) gene are common driver oncogenes in non-small cell lung cancer (NSCLC). Studies have shown that afatinib is beneficial for NSCLC patients with rare EGFR mutations. However, the effectiveness of tyrosine kinase inhibitors (TKIs) against the G719X (G719A, G719C and G719S) mutation has not been fully established. Herein, using the CRISPR method, the EGFR G719X mutant cell lines were constructed to assess the sensitivity of the rare mutation G719X in NSCLC. WZ3146, a novel mutation-selective EGFR inhibitor, was conducted transcriptome sequencing and in vitro experiments. The results showed that WZ3146 induced cytotoxic effects, inhibited growth vitality and proliferation via ERK and AKT pathway in the EGFR G719X mutant cells. Our findings suggest that WZ3146 may be a promising treatment option for NSCLC patients with the EGFR exon 18 substitution mutation G719X.

Dietary ellagic acid blocks inflammation-associated atherosclerotic plaque formation in cholesterol-fed apoE-deficient mice

BACKGROUND/OBJECTIVES

Atherosclerosis particularly due to high circulating level of low-density lipoprotein is a major cause of cardiovascular diseases. Ellagic acid is a natural polyphenolic compound rich in pomegranates and berries. Our previous study showed that ellagic acid improved functionality of reverse cholesterol transport in murine model of atherosclerosis. The aim of this study is to investigate whether ellagic acid inhibited inflammation-associated atherosclerotic plaque formation in cholesterol-fed apolipoprotein E (apoE)-knockout (KO) mice.

MATERIALS/METHODS

Wild type mice and apoE-KO mice were fed a cholesterol-rich Paigen diet for 10 weeks to induce severe atherosclerosis. Concurrently, 10 mg/kg ellagic acid was orally administered to the apoE-KO mice. Plaque lesion formation and lipid deposition were examined by staining with hematoxylin and eosin, Sudan IV and oil red O.

RESULTS

The plasma leukocyte profile of cholesterol-fed mice was not altered by apoE deficiency. Oral administration of ellagic acid attenuated plaque lesion formation and lipid deposition in the aorta tree of apoE-KO mice. Ellagic acid substantially reduced plasma levels of soluble vascular cell adhesion molecule and interferon-γ in Paigen diet-fed apoE-KO mice. When 10 mg/kg ellagic acid was administered to cholesterol-fed apoE-KO mice, the levels of CD68 and MCP-1 were strongly reduced in aorta vessels. The protein expression level of nitric oxide synthase-2 (NOS2) in the aorta was highly enhanced by supplementation of ellagic acid to apoE-KO mice, but the expression level of heme oxygenase-1 (HO-1) in the aorta was reduced. Furthermore, ellagic acid diminished the increased aorta expression of the inflammatory adhesion molecules in cholesterol-fed apoE-KO mice. The treatment of ellagic acid inhibited the scavenger receptor-B1 expression in the aorta of apoE-KO mice, while the cholesterol efflux-related transporters were not significantly changed.

CONCLUSION

These results suggest that ellagic acid may be an atheroprotective compound by attenuating apoE deficiency-induced vascular inflammation and reducing atherosclerotic plaque lesion formation.

Iron chelators as mitophagy agents: Potential and limitations

Mitochondrial autophagy (mitophagy) is very important process for the maintenance of cellular homeostasis, functionality and survival. Its dysregulation is associated with high risk and progression numerous serious diseases (e.g., oncological, neurodegenerative and cardiovascular ones). Therefore, targeting mitophagy mechanisms is very hot topic in the biological and medicinal research. The interrelationships between the regulation of mitophagy and iron homeostasis are now becoming apparent. In short, mitochondria are central point for the regulation of iron homeostasis, but change in intracellular cheatable iron level can induce/repress mitophagy. In this review, relationships between iron homeostasis and mitophagy are thoroughly discussed and described. Also, therapeutic applicability of mitophagy chelators in the context of individual diseases is comprehensively and critically evaluated.

Oxidative Stress and Age-Related Tumors

Oxidative stress is the result of the imbalance between reactive oxygen and nitrogen species (RONS), which are produced by several endogenous and exogenous processes, and antioxidant defenses consisting of exogenous and endogenous molecules that protect biological systems from free radical toxicity. Oxidative stress is a major factor in the aging process, contributing to the accumulation of cellular damage over time. Oxidative damage to cellular biomolecules, leads to DNA alterations, lipid peroxidation, protein oxidation, and mitochondrial dysfunction resulting in cellular senescence, immune system and tissue dysfunctions, and increased susceptibility to age-related pathologies, such as inflammatory disorders, cardiovascular and neurodegenerative diseases, diabetes, and cancer. Oxidative stress-driven DNA damage and mutations, or methylation and histone modification, which alter gene expression, are key determinants of tumor initiation, angiogenesis, metastasis, and therapy resistance. Accumulation of genetic and epigenetic damage, to which oxidative stress contributes, eventually leads to unrestrained cell proliferation, the inhibition of cell differentiation, and the evasion of cell death, providing favorable conditions for tumorigenesis. Colorectal, breast, lung, prostate, and skin cancers are the most frequent aging-associated malignancies, and oxidative stress is implicated in their pathogenesis and biological behavior. Our aim is to shed light on the molecular and cellular mechanisms that link oxidative stress, aging, and cancers, highlighting the impact of both RONS and antioxidants, provided by diet and exercise, on cellular senescence, immunity, and development of an antitumor response. The dual role of ROS as physiological regulators of cell signaling responsible for cell damage and diseases, as well as its use for anti-tumor therapeutic purposes, will also be discussed. Managing oxidative stress is crucial for promoting healthy aging and reducing the risk of age-related tumors.

Blue light photobiomodulation induced osteosarcoma cell death by facilitating ferroptosis and eliciting an incomplete tumor cell stress response

To investigate the potential of blue light photobiomodulation (PBM) in inducing ferroptosis, a novel form of regulated cell death, in OS cells, considering its known effectiveness in various cancer models. In this investigation, we exposed human OS cell lines, HOS and MG63, to different wavelengths (420, 460 and 480 nm) of blue light at varying irradiances, and examined cellular responses such as viability, apoptosis, levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Transcriptome sequencing was employed to unravel the molecular mechanisms underlying blue light-induced effects, with validation via quantitative real-time PCR (qRT-PCR). Our findings revealed a wavelength- and time-dependent decrease in cell viability, accompanied by increased apoptosis and oxidative stress. Transcriptomic analysis identified differential expression of genes associated with ferroptosis, oxidative stress, and iron metabolism, further validated by qRT-PCR. These results implicated ferroptosis as a significant mechanism in the blue light-induced death of OS cells, potentially mediated by ROS generation and disruption of iron homeostasis. Also, An incomplete stress response was observed in MG63 cells induced by blue light exposure. Hence, blue light PBM holds promise as a therapeutic approach in OS clinical investigations; however, additional exploration of its underlying mechanisms remains imperative.

NCI677397 targeting USP24-mediated induction of lipid peroxidation induces ferroptosis in drug-resistant cancer cells

Cancer represents a profound challenge to healthcare systems and individuals worldwide. The development of multiple drug resistance is a major problem in cancer therapy and can result in progression of the disease. In our previous studies, we developed small-molecule inhibitors targeting ubiquitin-specific peptidase 24 (USP24) to combat drug-resistant lung cancer. Recently, we found that the USP24 inhibitor NCI677397 induced ferroptosis, a type of programmed cell death, in drug-resistant cancer cells by increasing lipid reactive oxygen species (ROS) levels. In the present study, we investigated the molecular mechanisms and found that the targeting of USP24 by NCI677397 increased gene expression of most lipogenesis-related genes, such as acyl-CoA synthetase long-chain family member 4 (ACSL4), and activated autophagy. In addition, the activity of several antioxidant enzymes, such as glutathione peroxidase 4 (GPX4) and dihydrofolate reductase (DHFR), was inhibited by NCI677397 treatment via an increase in protein degradation, thereby inducing lipid ROS production and lipid peroxidation. In summary, we demonstrated that NCI677397 induced a marked increase in lipid ROS levels, subsequently causing lipid peroxidation and leading to the ferroptotic death of drug-resistant cancer cells. Our study provides new insights into the clinical use of USP24 inhibitors as ferroptosis inducers (FINs) to block drug resistance during chemotherapy.

HMOX1: A pivotal regulator of prognosis and immune dynamics in ovarian cancer

BACKGROUND

This study investigates the intricate role of Heme Oxygenase 1 (HMOX1) in ovarian cancer, emphasizing its prognostic significance, influence on immune cell infiltration, and impact on the malignant characteristics of primary ovarian cancer cells.

MATERIALS AND METHODS

Our research began with an analysis of HMOX1 expression and its prognostic implications using data from The Cancer Genome Atlas (TCGA) dataset, supported by immunohistochemical staining. Further analyses encompassed co-expression studies, Gene Ontology (GO) annotations, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. We utilized the TIMER and TISIDB platforms to evaluate the immunotherapeutic potential of HMOX1. Additionally, in vitro studies that involved modulating HMOX1 levels in primary ovarian cancer cells were conducted to confirm its biological functions.

RESULTS

Our findings indicate a significant overexpression of HMOX1 in ovarian cancer, which correlates with increased tumor malignancy and poorer prognosis. HMOX1 was shown to significantly modulate the infiltration of immune cells, particularly neutrophils and macrophages. Single-cell RNA sequencing (scRNA-seq) analysis revealed that HMOX1 is predominantly expressed in tumor-associated macrophages (TAMs), with a positive correlation to chemokines and their receptors. An increase in HMOX1 levels was associated with heightened levels of immunoinhibitors, immunostimulators, and MHC molecules. Functional assays demonstrated that HMOX1 knockdown promotes apoptosis, attenuating cell proliferation and invasion, while its overexpression yields opposing effects.

CONCLUSION

HMOX1 emerges as a critical therapeutic target, intricately involved in immunomodulation, prognosis, and the malignant behavior of ovarian cancer. This highlights HMOX1 as a potential biomarker and therapeutic target in the fight against ovarian cancer.

Heme Oxygenase-1 and Prostate Cancer: Function, Regulation, and Implication in Cancer Therapy

Prostate cancer (PC) is a significant cause of mortality in men worldwide, hence the need for a comprehensive understanding of the molecular mechanisms underlying its progression and resistance to treatment. Heme oxygenase-1 (HO-1), an inducible enzyme involved in heme catabolism, has emerged as a critical player in cancer biology, including PC. This review explores the multifaceted role of HO-1 in PC, encompassing its function, regulation, and implications in cancer therapy. HO-1 influences cell proliferation, anti-apoptotic pathways, angiogenesis, and the tumor microenvironment, thereby influencing tumor growth and metastasis. HO-1 has also been associated with therapy resistance, affecting response to standard treatments. Moreover, HO-1 plays a significant role in immune modulation, affecting the tumor immune microenvironment and potentially influencing therapy outcomes. Understanding the intricate balance of HO-1 in PC is vital for developing effective therapeutic strategies. This review further explores the potential of targeting HO-1 as a therapeutic approach, highlighting challenges and opportunities. Additionally, clinical implications are discussed, focusing on the prognostic value of HO-1 expression and the development of novel combined therapies to augment PC sensitivity to standard treatment strategies. Ultimately, unraveling the complexities of HO-1 in PC biology will provide critical insights into personalized treatment approaches for PC patients.

A highly fluorescent and readily accessible all-organic photosensitizer model for advancing image-guided cancer PDT

The potential of using image-guided photodynamic therapy (ig-PDT) for cancer, especially with highly biocompatible fluorescent agents free of heavy atoms, is well recognized. This is due to key advantages related to minimizing adverse side effects associated with standard cancer chemotherapy. However, this theragnostic approach is strongly limited by the lack of synthetically-accessible and easily-modulable chemical scaffolds, enabling the rapid design and construction of advanced agents for clinical ig-PDT. In fact, there are still very few ig-PDT agents clinically approved. Herein we report a readily accessible, easy-tunable and highly fluorescent all-organic small photosensitizer, as a model design for accelerating the development and translation of advanced ig-PDT agents for cancer. This scaffold is based on BODIPY, which assures high fluorescence, accessibility, and ease of performance adaptation by workable chemistry. The optimal PDT performance of this BODIPY dye, tested in highly resistant pancreatic cancer cells, despite its high fluorescent behavior, maintained even after fixation and cancer cell death, is based on its selective accumulation in mitochondria. This induces apoptosis upon illumination, as evidenced by proteomic studies and flow cytometry. All these characteristics make the reported BODIPY-based fluorescent photosensitizer a valuable model for the rapid development of ig-PDT agents for clinical use.

HO-1-induced autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to reduce gut permeability in cholestatic liver disease

OBJECTIVES

The gut-liver axis disruption is a unified pathogenetic principle of cholestatic liver disease (CSLD). Increased gut permeability is the leading cause of gut-liver axis disruption. HO-1 is capable of protecting against gut-liver axis injury. However, it has rarely been reported whether autophagy is involved in HO-1 protecting gut-liver barrier integrity and the underlying mechanism.

MATERIALS AND METHODS

Mice underwent bile duct ligation (BDL) was established as CSLD model in vivo. Caco-2 cells with LPS treatment was established as in vitro cell model. Immunofluorescence, western blot and transepithelial electrical resistance (TER) assay were used to observe epithelial tight junction (TJ) and autophagy. Liver injury and fibrosis were evaluated as well through H&E staining, masson staining, sirius red staining and ELISA.

RESULTS AND CONCLUSIONS

Our study demonstrated that the epithelial TJ and TER were notably reduced both in BDL mice and in LPS treated intestinal epithelial cells. Increased HO-1 expression could significantly induce intestinal epithelial cell autophagy. Additionally, this increased autophagy level reversed the reduction effects of BDL or LPS on epithelial TJ and TER in vivo and in vitro, therefore decreased transaminase level in serum and relieved liver fibrosis in BDL mice. Besides, increased autophagy level in turn upregulated the expression of HO-1 by p62 degradation of Keap1 and subsequent activation of Nrf2 pathway. Collectively, these results indicate that HO-1 reduces gut permeability by enhancing autophagy level in CSLD, the increased autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to further improve gut-liver axis disruption. Therefore, our study confirms the critical role of autophagy in HO-1 ameliorating gut-liver axis injury during CSLD, highlighting HO-1 as a promising therapeutic target.

The powerful antioxidant effects of plant fruits, flowers, and leaves help to improve retinal damage and support the relief of visual fatigue

With the popularization of electronic products, visual fatigue is inevitably frequent. The causes of visual fatigue are varied, but from the perspective of physiological mechanisms, it is mainly closely related to retinal function or structural damage, especially the light source from various mobile devices and office equipments nowadays, which induces oxidative stress damage in the retina and exacerbates the degree of visual fatigue, resulting in the inability to use the eyes for a long period of time, pain in the eyes and periorbital area, blurred vision, dry eyes, tearing, and other discomforts. Food ingredients derived from natural plants have greater application in relieving visual fatigue. Therefore, this paper presents a detailed compilation of six plants that are widely used for their visual fatigue-relieving function, in the hope of providing more raw material choices for the development of products with visual fatigue-relieving functions in the future.

Targeting heme degradation pathway augments prostate cancer cell sensitivity to docetaxel-induced apoptosis and attenuates migration

Introduction

Chemotherapy, notably docetaxel (Doc), stands as the primary treatment for castration-resistant prostate cancer (CRPC). However, its efficacy is hindered by side effects and chemoresistance. Hypoxia in prostate cancer (PC) correlates with chemoresistance to Doc-induced apoptosis via Heme Oxygenase-1 (HO-1) modulation, a key enzyme in heme metabolism. This study investigated targeting heme degradation pathway via HO-1 inhibition to potentiate the therapeutic efficacy of Doc in PC.

Methods

Utilizing diverse PC cell lines, we evaluated HO-1 inhibition alone and with Doc on viability, apoptosis, migration, and epithelial- to- mesenchymal transition (EMT) markers and elucidated the underlying mechanisms.

Results

HO-1 inhibition significantly reduced PC cell viability under hypoxic and normoxic conditions, enhancing Doc-induced apoptosis through interconnected mechanisms, including elevated reactive oxygen species (ROS) levels, glutathione cycle disruption, and modulation of Signal Transducer and Activator of Transcription 1 (STAT1) pathway. The interplay between STAT1 and HO-1 suggests its reliance on HO-1 activation. Additionally, a decrease in cell migration and downregulation of EMT markers (vimentin and snail) were observed, indicating attenuation of mesenchymal phenotype.

Discussion

In conclusion, the combination of HO-1 inhibition with Doc holds promise for improving therapeutic outcomes and advancing clinical management in PC.

Heat stress affects mammary metabolism by influencing the plasma flow to the glands

BACKGROUND

Environmental heat stress (HS) can have detrimental effects on milk production by compromising the mammary function. Mammary plasma flow (MPF) plays a crucial role in nutrient supply and uptake in the mammary gland. In this experiment, we investigated the physiological and metabolic changes in high-yielding cows exposed to different degrees of HS: no HS with thermal-humidity index (THI) below 68 (No-HS), mild HS (Mild-HS, 68 ≤ THI ≤ 79), and moderate HS (Mod-HS, 79 < THI ≤ 88) in their natural environment. Our study focused on the changes in blood oxygen supply and mammary glucose uptake and utilization.

RESULTS

Compared with No-HS, the MPF of dairy cows was greater (P < 0.01) under Mild-HS, but was lower (P < 0.01) in cows under Mod-HS. Oxygen supply and consumption exhibited similar changes to the MPF under different HS, with no difference in ratio of oxygen consumption to supply (P = 0.46). The mammary arterio-vein differences in glucose concentration were lower (P < 0.05) under Mild- and Mod-HS than under no HS. Glucose supply and flow were significantly increased (P < 0.01) under Mild-HS but significantly decreased (P < 0.01) under Mod-HS compared to No-HS. Glucose uptake (P < 0.01) and clearance rates (P < 0.01) were significantly reduced under Mod-HS compared to those under No-HS and Mild-HS. Under Mild-HS, there was a significant decrease (P < 0.01) in the ratio of lactose yield to mammary glucose supply compared to that under No-HS and Mod-HS, with no difference (P = 0.53) in the ratio of lactose yield to uptaken glucose among different HS situations.

CONCLUSIONS

Degrees of HS exert different influences on mammary metabolism, mainly by altering MPF in dairy cows. The output from this study may help us to develop strategies to mitigate the impact of different degrees of HS on milk production.

Esculin induces endoplasmic reticulum stress and drives apoptosis and ferroptosis in colorectal cancer via PERK regulating eIF2α/CHOP and Nrf2/HO-1 cascades

ETHNOPHARMACOLOGICAL RELEVANCE

Cortex fraxini (also known as Qinpi), the bark of Fraxinus rhynchophylla Hance and Fraxinus stylosa Lingelsh, constitutes a crucial component in several traditional Chinese formulas (e.g., Baitouweng Tang, Jinxiao Formula, etc.) and has demonstrated efficacy in alleviating intestinal carbuncle and managing diarrhea. Cortex fraxini has demonstrated commendable anticancer activity in the realm of Chinese ethnopharmacology; nevertheless, the underlying mechanisms against colorectal cancer (CRC) remain elusive.

AIM OF THE STUDY

Esculin, an essential bioactive compound derived from cortex fraxini, has recently garnered attention for its ability to impede viability and induce apoptosis in cancer cells. This investigation aims to assess the therapeutic potential of esculin in treating CRC and elucidate the underlying mechanisms.

MATERIALS AND METHODS

The impact of esculin on CRC cell viability was assessed using CCK-8 assay, Annexin V/PI staining, and Western blotting. Various cell death inhibitors, along with DCFH-DA, ELISA, biochemical analysis, and Western blotting, were employed to delineate the modes through which esculin induces HCT116 cells death. Inhibitors and siRNA knockdown were utilized to analyze the signaling pathways influenced by esculin. Additionally, an azomethane/dextran sulfate sodium (AOM/DSS)-induced in vivo CRC mouse model was employed to validate esculin's potential in inhibiting tumorigenesis and to elucidate its underlying mechanisms.

RESULTS

Esculin significantly suppressed the viability of various CRC cell lines, particularly HCT116 cells. Investigation with diverse cell death inhibitors revealed that esculin-induced cell death was associated with both apoptosis and ferroptosis. Furthermore, esculin treatment triggered cellular lipid peroxidation, as evidenced by elevated levels of malondialdehyde (MDA) and decreased levels of glutathione (GSH), indicative of its propensity to induce ferroptosis in HCT116 cells. Enhanced protein levels of protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and p-eIF2α suggested that esculin induced cellular endoplasmic reticulum (ER) stress, subsequently activating the Nrf2/ARE signaling pathway and initiating the transcriptional expression of heme oxygenase (HO)-1. Esculin-induced excessive expression of HO-1 could potentially lead to iron overload in HCT116 cells. Knockdown of Ho-1 significantly attenuated esculin-induced ferroptosis, underscoring HO-1 as a critical mediator of esculin-induced ferroptosis in HCT116 cells. Furthermore, utilizing an AOM/DSS-induced colorectal cancer mouse model, we validated that esculin potentially inhibits the onset and progression of colon cancer by inducing apoptosis and ferroptosis in vivo.

CONCLUSIONS

These findings provide comprehensive insights into the dual induction of apoptosis and ferroptosis in HCT116 cells by esculin. The activation of the PERK signaling pathway, along with modulation of downstream eIF2α/CHOP and Nrf2/HO-1 cascades, underscores the mechanistic basis supporting the clinical application of esculin on CRC treatment.

Inside the genome: understanding genetic influences on oxidative stress

Genetics is a key factor that governs the susceptibility to oxidative stress. In the body, oxidative burden is regulated by the balance between the prooxidant genes that orchestrate processes that produce oxidant species, while the antioxidant genes aid those involved in scavenging these species. Together, the two components aid in maintaining the oxidative balance in the body. Genetic variations can influence the expression and activity of the encoded proteins which can then affect their efficiency in regulating redox processes, thereby increasing the risk of oxidative stress. This review studies single nucleotide polymorphisms (SNPs) that bear relevance to oxidative stress by exploring the variations in the prooxidant genes, such as XDH, CYBA, CYP1A1, PTGS2, NOS, and MAO and antioxidant genes including SOD, CAT, GPX, GSS, GLUL, GSR, GSTM1, GSTM5, GSTP1, TXN and HMOX1. Early identification of individuals at the increased risk of oxidative stress is possible from the assessment of sequence of these genes. Integrating genetic insights into oxidative stress management measures can pave the way for personalized medicine that tailors' healthcare approaches to individual genetic profiles. Effective genetic assessment along with routine quantification of biological markers can improve and monitor treatment strategies, enhancing mitigation approaches that maintain cellular health and promote longevity.

Neuregulin-1, a member of the epidermal growth factor family, mitigates STING-mediated pyroptosis and necroptosis in ischaemic flaps

Background

Ensuring the survival of the distal end of a random flap during hypoperfusion (ischaemia) is difficult in clinical practice. Effective prevention of programmed cell death is a potential strategy for inhibiting ischaemic flap necrosis. The activation of stimulator of interferon genes (STING) pathway promotes inflammation and leads to cell death. The epidermal growth factor family member neuregulin-1 (NRG1) reduces cell death by activating the protein kinase B (AKT) signalling pathway. Moreover, AKT signalling negatively regulates STING activity. We aimed to verify the efficacy of NRG1 injection in protecting against flap necrosis. Additionally, we investigated whether NRG1 effectively enhances ischemic flap survival by inhibiting pyroptosis and necroptosis through STING suppression.

Methods

A random-pattern skin flap model was generated on the backs of C57BL/6 mice. The skin flap survival area was determined. The blood supply and vascular network of the flap was assessed by laser Doppler blood flow analysis. Cluster of differentiation 34 immunohistochemistry (IHC) and haematoxylin and eosin (H&E) staining of the flap sections revealed microvessels. Transcriptome sequencing analysis revealed the mechanism by which NRG1 promotes the survival of ischaemic flaps. The levels of angiogenesis, oxidative stress, necroptosis, pyroptosis and indicators associated with signalling pathways in flaps were examined by IHC, immunofluorescence and Western blotting. Packaging adeno-associated virus (AAV) was used to activate STING in flaps.

Results

NRG1 promoted the survival of ischaemic flaps. An increased subcutaneous vascular network and neovascularization were found in ischaemic flaps after the application of NRG1. Transcriptomic gene ontology enrichment analysis and protein level detection indicated that necroptosis, pyroptosis and STING activity were reduced in the NRG1 group. The phosphorylation of AKT and forkhead box O3a (FOXO3a) were increased after NRG1 treatment. The increased expression of STING in flaps induced by AAV reversed the therapeutic effect of NRG1. The ability of NRG1 to phosphorylate AKT-FOXO3a, inhibit STING and promote flap survival was abolished after the application of the AKT inhibitor MK2206.

Conclusions

NRG1 inhibits pyroptosis and necroptosis by activating the AKT-FOXO3a signalling pathway to suppress STING activation and promote ischaemic flap survival.

Dihydromyricetin regulates KEAP1-Nrf2 pathways to enhance the survival of ischemic flap

In clinical flap practice, there are a lot of studies being done on how to promote the survival of distal random flap necrosis in the hypoxic and ischemic state. As a traditional Chinese medicine, dihydromyricetin (DHM) is crucial in preventing oxidative stress and apoptosis in a number of disorders. In this work, we examined the impact of DHM on the ability to survive of ischemia flaps and looked into its fundamental mechanism. Our results showed that DHM significantly increased the ischemic flaps' survival area, encouraged angiogenesis and blood flow, reduced oxidative stress and apoptosis, and stimulated KEAP1-Nrf2 (Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor) signaling pathways. Adeno-associated virus (AAV) upregulation of KEAP1 expression also negated the favorable effects of DHM on flap survival. By activating KEAP1-Nrf2 signaling pathways, DHM therapy promotes angiogenesis while reducing oxidative stress and apoptosis.

Cardiovascular Disease and miRNAs: Possible Oxidative Stress-Regulating Roles of miRNAs

MicroRNAs (miRNAs) have been highlighted as key players in numerous diseases, and accumulating evidence indicates that pathological expressions of miRNAs contribute to both the development and progression of cardiovascular diseases (CVD), as well. Another important factor affecting the development and progression of CVD is reactive oxygen species (ROS), as well as the oxidative stress they may impose on the cells. Considering miRNAs are involved in virtually every biological process, it is not unreasonable to assume that miRNAs also play critical roles in the regulation of oxidative stress. This narrative review aims to provide mechanistic insights on possible oxidative stress-regulating roles of miRNAs in cardiovascular diseases based on differentially expressed miRNAs reported in various cardiovascular diseases and their empirically validated targets that have been implicated in the regulation of oxidative stress.

Piperlongumine: the amazing amide alkaloid from Piper in the treatment of breast cancer

Piperlongumine (PL), an alkaloid found primarily in the fruits and roots of the plant Piper longum L. (Piperaceae), is a natural compound that exhibits potent activity against various cancer cell proliferation. The most frequently caused malignancy in women globally, breast cancer (BC), has been demonstrated to be significantly inhibited by PL. Apoptosis, cell cycle arrest, increased ROS generation, and changes in the signalling protein's expression are all caused by the numerous signalling pathways that PL impacts. Since BC cells resist conventional chemotherapeutic drugs (doxorubicin, docetaxel etc.), researchers have shown that the drugs in combination with PL can exhibit a synergistic effect, greater than the effects of the drug or PL alone. Recently, techniques for drug packaging based on nanotechnology have been employed to improve PL release. The review has presented an outline of the chemistry of PL, its molecular basis in BC, its bioavailability, toxicity, and nanotechnological applications. An attempt to understand the future prospects and direction of research about the compound has also been discussed.

HH-A, a modified honokiol, protects against cerebral ischemia/reperfusion induced brain injury in rodent via Nrf2/HO-1 signaling pathways

Honokiol, a bioactive component found in Magnolia officinalis, has shown in protecting against ischemic stroke in animal models. However, its poor water solubility has limited its clinical applications. In this study, we introduced a hydrophilic building block on the aromatic ring of honokiol, resulting in the synthesis of four new compounds (HH-A, -B, -C and -D) with significantly improved water solubility. We then investigated the neuroprotective effects of these compounds in mouse and rat models of transient middle cerebral artery occlusion/reperfusion (tMCAO/R) brain injury. Among the compounds tested, HH-A, also known as (S)-6-((3',5-diallyl-2,4'-dihydroxy-[1,1'-biphenyl]-3-yl)amino)-6-oxohexane-1,5-diaminium chloride, showed the most promising results. HH-A was found to significantly reduced the infarct volume and brain edema in mice. It also outperformed the other three compounds and honokiol, even surpassing the effects of edaravone dexborneol. Additionally, HH-A demonstrated dose-dependent improvements in body weight, neurological deficits, and infarct volume. Further analysis in tMCAO/R rat model revealed that HH-A treatment led to significant upregulations of Nrf2 and HO-1 in the brain. HH-A also significantly reduced the expression of HNE, and exhibited anti-apoptotic effects by decreasing the expression of Bax and increasing the expression of Bcl-2. This was further supported by a decrease in the number of TUNEL positive cells. Taken together, the neuroprotective effects of HH-A may be attributed to its ability to target the Nrf2/HO-1 signaling pathway, leading to reduced oxidative stress and apoptosis in the brain. These findings suggest that HH-A has potential as a therapeutic agent for the treatment of ischemic stroke.

Phloroglucinol Enhances Anagen Signaling and Alleviates H2O2-Induced Oxidative Stress in Human Dermal Papilla Cells

Phloroglucinol (PG) is one of the abundant isomeric benzenetriols in brown algae. Due to its polyphenolic structure, PG exhibits various biological activities. However, the impact of PG on anagen signaling and oxidative stress in human dermal papilla cells (HDPCs) is unknown. In this study, we investigated the therapeutic potential of PG for improving hair loss. A non-cytotoxic concentration of PG increased anagen-inductive genes and transcriptional activities of β-Catenin. Since several anagen-inductive genes are regulated by β-Catenin, further experiments were performed to elucidate the molecular mechanism by which PG upregulates anagen signaling. Various biochemical analyses revealed that PG upregulated β-Catenin signaling without affecting the expression of Wnt. In particular, PG elevated the phosphorylation of protein kinase B (AKT), leading to an increase in the inhibitory phosphorylation of glycogen synthase kinase 3 beta (GSK3β) at serine 9. Treatment with the selective phosphoinositide 3-kinase/AKT inhibitor, LY294002, restored the increased AKT/GSK3β/β-Catenin signaling and anagen-inductive proteins induced by PG. Moreover, conditioned medium from PG-treated HDPCs promoted the proliferation and migration of human epidermal keratinocytes via the AKT signaling pathway. Subsequently, we assessed the antioxidant activities of PG. PG ameliorated the elevated oxidative stress markers and improved the decreased anagen signaling in hydrogen peroxide (H2O2)-induced HDPCs. The senescence-associated β-galactosidase staining assay also demonstrated that the antioxidant abilities of PG effectively mitigated H2O2-induced senescence. Overall, these results indicate that PG potentially enhances anagen signaling and improves oxidative stress-induced cellular damage in HDPCs. Therefore, PG can be employed as a novel therapeutic component to ameliorate hair loss symptoms.

Self-Reinforced Bimetallic Mito-Jammer for Ca2+ Overload-Mediated Cascade Mitochondrial Damage for Cancer Cuproptosis Sensitization

Overproduction of reactive oxygen species (ROS), metal ion accumulation, and tricarboxylic acid cycle collapse are crucial factors in mitochondria-mediated cell death. However, the highly adaptive nature and damage-repair capabilities of malignant tumors strongly limit the efficacy of treatments based on a single treatment mode. To address this challenge, a self-reinforced bimetallic Mito-Jammer is developed by incorporating doxorubicin (DOX) and calcium peroxide (CaO2) into hyaluronic acid (HA) -modified metal-organic frameworks (MOF). After cellular, Mito-Jammer dissociates into CaO2 and Cu2+ in the tumor microenvironment. The exposed CaO2 further yields hydrogen peroxide (H2O2) and Ca2+ in a weakly acidic environment to strengthen the Cu2+-based Fenton-like reaction. Furthermore, the combination of chemodynamic therapy and Ca2+ overload exacerbates ROS storms and mitochondrial damage, resulting in the downregulation of intracellular adenosine triphosphate (ATP) levels and blocking of Cu-ATPase to sensitize cuproptosis. This multilevel interaction strategy also activates robust immunogenic cell death and suppresses tumor metastasis simultaneously. This study presents a multivariate model for revolutionizing mitochondria damage, relying on the continuous retention of bimetallic ions to boost cuproptosis/immunotherapy in cancer.

Targeting mitochondrial bioenergetics by combination treatment with imatinib and dichloroacetate in human erythroleukemic K‑562 and colorectal HCT‑116 cancer cells

Tumor malignant cells are characterized by dysregulation of mitochondrial bioenergetics due to the 'Warburg effect'. In the present study, this metabolic imbalance was explored as a potential target for novel cancer chemotherapy. Imatinib (IM) downregulates the expression levels of SCΟ2 and FRATAXIN (FXN) genes involved in the heme‑dependent cytochrome c oxidase biosynthesis and assembly pathway in human erythroleukemic IM‑sensitive K‑562 chronic myeloid leukemia cells (K‑562). In the present study, it was investigated whether the treatment of cancer cells with IM (an inhibitor of oxidative phosphorylation) separately, or together with dichloroacetate (DCA) (an inhibitor of glycolysis), can inhibit cell proliferation or cause death. Human K‑562 and IM‑chemoresistant K‑562 chronic myeloid leukemia cells (K‑562R), as well as human colorectal carcinoma cells HCT‑116 (+/+p53) and (‑/‑p53, with double TP53 knock-in disruptions), were employed. Treatments of these cells with either IM (1 or 2 µM) and/or DCA (4 mΜ) were also assessed for the levels of several process biomarkers including SCO2, FXN, lactate dehydrogenase A, glyceraldehyde‑3‑phosphate dehydrogenase, pyruvate kinase M2, hypoxia inducing factor‑1a, heme oxygenase‑1, NF‑κB, stem cell factor and vascular endothelial growth factor via western blot analysis. Computational network biology models were also applied to reveal the connections between the ten proteins examined. Combination treatment of IM with DCA caused extensive cell death (>75%) in K‑562 and considerable (>45%) in HCT‑116 (+/+p53) cultures, but less in K‑562R and HCT‑116 (‑/‑p53), with the latter deficient in full length p53 protein. Such treatment, markedly reduced reactive oxygen species levels, as measured by flow‑cytometry, in K‑562 cells and affected the oxidative phosphorylation and glycolytic biomarkers in all lines examined. These findings indicated, that targeting of cancer mitochondrial bioenergetics with such a combination treatment was very effective, although chemoresistance to IM in leukemia and the absence of a full length p53 in colorectal cells affected its impact.

Pathological significance of heme oxygenase-1 as a potential tumor promoter in heme-induced colorectal carcinogenesis

The significance of the heme-metabolizing enzyme heme oxygenase-1 (HMOX1) in the pathogenesis of colorectal cancer (CRC) has not been fully explored. HMOX1 cytoprotection is imperative to limit oxidative stress. However, its roles in preventing carcinogenesis in response to high levels of heme are not thoroughly understood. This study reviews various mechanisms associated with the paradoxical role of HMOX1, which is advantageous for tumor growth, refractoriness, and survival of cancer cells amid oxidative stress in heme-induced CRC. The alternate role of HMOX1 promotes cell proliferation and metastasis through immune modulation and angiogenesis. Inhibiting HMOX1 has been found to reverse tumor promotion. Thus, HMOX1 acts as a conditional tumor promoter in CRC pathogenesis.

Lichen pectin-containing polysaccharide from Xanthoria elegans and its ability to effectively protect LX-2 cells from H2O2-induced oxidative damage

Xanthoria elegans, a drought-tolerant lichen, is the original plant of the traditional Chinese medicine "Shihua" and effectively treats a variety of liver diseases. However, thus far, the hepatoprotective effects of polysaccharides, the most important chemical constituents of X. elegans, have not been determined. The aim of this study was to screen the polysaccharide fraction for hepatoprotective activity by using free radical scavenging assays and a H2O2-induced Lieming Xu-2 cell (LX-2) oxidative damage model and to elucidate the chemical composition of the bioactive polysaccharide fraction. In the present study, three polysaccharide fractions (XEP-50, XEP-70 and XEP-90) were obtained from X. elegans by hot-water extraction, DEAE-cellulose anion exchange chromatography separation and ethanol gradient precipitation. Among the three polysaccharide fractions, XEP-70 exhibited the best antioxidant activity in free radical scavenging capacity and reducing power assays. Structural studies showed that XEP-70 was a pectin-containing heteropolysaccharide fraction that was composed mainly of (1 → 4)-linked and (1 → 4,6)-linked α-D-Glcp, (1 → 4)-linked α-D-GalpA, (1 → 2)-linked, (1 → 6)-linked and (1 → 2,6)-linked α-D-Manp, and (1 → 6)-linked and (1 → 2,6)-linked β-D-Galf. Furthermore, XEP-70 exhibited effectively protect LX-2 cells against H2O2-induced oxidative damage by enhancing cellular antioxidant capacity by activating the Nrf2/Keap1/ARE signaling pathway. Thus, XEP-70 has good potential to protect hepatic stellate cells against oxidative damage.

Targeting Nrf2 to treat thyroid cancer

Oxidative stress (OS) is recognized as a contributing factor in the development and progression of thyroid cancer. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a pivotal transcription factor involved in against OS generated by excessive reactive oxygen species (ROS). It governs the expression of a wide array of genes implicated in detoxification and antioxidant pathways. However, studies have demonstrated that the sustained activation of Nrf2 can contribute to tumor progression and drug resistance in cancers. The expression of Nrf2 was notably elevated in papillary thyroid cancer tissues compared to normal tissues, indicating that Nrf2 may play an oncogenic role in the development of papillary thyroid cancer. Nrf2 and its downstream targets are involved in the progression of thyroid cancer by impacting the prognosis and ferroptosis. Furthermore, the inhibition of Nrf2 can increase the sensitivity of target therapy in thyroid cancer. Therefore, Nrf2 appears to be a potential therapeutic target for the treatment of thyroid cancer. This review summarized current data on Nrf2 expression in thyroid cancer, discussed the function of Nrf2 in thyroid cancer, and analyzed various strategies to inhibit Nrf2.

Induction of ferroptosis by natural phenols: A promising strategy for cancer therapy

In recent years, heightened interest surrounds the exploration of natural phenols as potential agents for cancer therapy, specifically by inducing ferroptosis, a unique form of regulated cell death characterized by iron-dependent lipid peroxidation. This review delves into the roles of key natural phenols, flavonoids, phenolic acids, curcumin, and stilbenes, in modulating ferroptosis and their underlying mechanisms. Emphasizing the significance of amino acid, lipid, and iron metabolism, the study elucidates the diverse pathways through which these phenols regulate ferroptosis. Notably, curcumin, a well-known polyphenol, exhibits multifaceted interactions with cellular components involved in ferroptosis regulation, providing a distinctive therapeutic avenue. Stilbenes, another phenolic class, demonstrate promising potential in influencing lipid metabolism and iron-dependent processes, contributing to ferroptotic cell death. Understanding the intricate interplay between these natural phenols and ferroptosis not only illuminates complex cellular regulatory networks but also unveils potential avenues for novel cancer therapies. Exploring these compounds as inducers of ferroptosis presents a promising strategy for targeted cancer treatment, capitalizing on the delicate balance between cellular metabolism and regulated cell death mechanisms. This article synthesizes current knowledge, aiming to stimulate further research into the therapeutic potential of natural phenols in the context of ferroptosis-mediated cancer therapy.

A Mechanistic Study of the Osteogenic Effect of Arecoline in an Osteoporosis Model: Inhibition of Iron Overload-Induced Osteogenesis by Promoting Heme Oxygenase-1 Expression

Iron overload-associated osteoporosis presents a significant challenge to bone health. This study examines the effects of arecoline (ACL), an alkaloid found in areca nut, on bone metabolism under iron overload conditions induced by ferric ammonium citrate (FAC) treatment. The results indicate that ACL mitigates the FAC-induced inhibition of osteogenesis in zebrafish larvae, as demonstrated by increased skeletal mineralization and upregulation of osteogenic genes. ACL attenuates FAC-mediated suppression of osteoblast differentiation and mineralization in MC3T3-E1 cells. RNA sequencing analysis suggests that the protective effects of ACL are related to the regulation of ferroptosis. We demonstrate that ACL inhibits ferroptosis, including oxidative stress, lipid peroxidation, mitochondrial damage, and cell death under FAC exposure. In this study, we have identified heme oxygenase-1 (HO-1) as a critical mediator of ACL inhibiting ferroptosis and promoting osteogenesis, which was validated by HO-1 knockdown and knockout experiments. The study links ACL to HO-1 activation and ferroptosis regulation in the context of bone metabolism. These findings provide new insights into the mechanisms underlying the modulation of osteogenesis by ACL. Targeting the HO-1/ferroptosis axis is a promising therapeutic approach for treating iron overload-induced bone diseases.

Bi-directional regulation of type I interferon signaling by heme oxygenase-1

Moderate activation of IFN-I contributes to the body's immune response, but its abnormal expression, stimulated by oxidative stress or other factors causes pathological damage. Heme oxygenase-1 (HO-1), induced by stress stimuli in the body, exerts a central role in cellular protection. Here we showed that HO-1 could promote IFN-1 under Spring Viremia of Carp virus (SVCV) infection and concomitantly attenuate the replication of SVCV. Further characterization of truncated mutants of HO-1 confirmed that intact HO-1 was essential for its antiviral function via IFN-I. Importantly, HO-1 inhibited the IFN-I signal by degrading the IRF3/7 through the autophagy pathway when it was triggered by H2O2 treatment. The iron ion-binding site (His28) was critical for HO-1 to degrade IRF3/7. HO-1 degradation of IRF3/7 is conserved in fish and mammals. Collectively, HO-1 regulates IFN-I positively under viral infection and negatively under oxidative stress, elucidating a mechanism by which HO-1 regulates IFN-I signaling in bi-directions.

Putative Molecular Mechanisms Underpinning the Inverse Roles of Mitochondrial Respiration and Heme Function in Lung Cancer and Alzheimer's Disease

Mitochondria are the powerhouse of the cell. Mitochondria serve as the major source of oxidative stress. Impaired mitochondria produce less adenosine triphosphate (ATP) but generate more reactive oxygen species (ROS), which could be a major factor in the oxidative imbalance observed in Alzheimer's disease (AD). Well-balanced mitochondrial respiration is important for the proper functioning of cells and human health. Indeed, recent research has shown that elevated mitochondrial respiration underlies the development and therapy resistance of many types of cancer, whereas diminished mitochondrial respiration is linked to the pathogenesis of AD. Mitochondria govern several activities that are known to be changed in lung cancer, the largest cause of cancer-related mortality worldwide. Because of the significant dependence of lung cancer cells on mitochondrial respiration, numerous studies demonstrated that blocking mitochondrial activity is a potent strategy to treat lung cancer. Heme is a central factor in mitochondrial respiration/oxidative phosphorylation (OXPHOS), and its association with cancer is the subject of increased research in recent years. In neural cells, heme is a key component in mitochondrial respiration and the production of ATP. Here, we review the role of impaired heme metabolism in the etiology of AD. We discuss the numerous mitochondrial effects that may contribute to AD and cancer. In addition to emphasizing the significance of heme in the development of both AD and cancer, this review also identifies some possible biological connections between the development of the two diseases. This review explores shared biological mechanisms (Pin1, Wnt, and p53 signaling) in cancer and AD. In cancer, these mechanisms drive cell proliferation and tumorigenic functions, while in AD, they lead to cell death. Understanding these mechanisms may help advance treatments for both conditions. This review discusses precise information regarding common risk factors, such as aging, obesity, diabetes, and tobacco usage.

Bilirubin and postpartum depression: an observational and Mendelian randomization study

Background

Postpartum depression (PPD) is one of the most common complications of delivery and is usually disregarded. Several risk factors of PPD have been identified, but its pathogenesis has not been completely understood. Serum bilirubin has been found to be a predictor of depression, whose relationship with PPD has not been investigated.

Methods

Observational research was performed followed by a two-sample Mendelian randomization (MR) analysis. From 2017 to 2020, the clinical data of pregnant women were retrospectively extracted. Logistic regression and random forest algorithm were employed to assess the risk factors of PPD, including the serum levels of total bilirubin and direct bilirubin. To further explore their potential causality, univariable and multivariable Mendelian randomization (MVMR) were conducted. Sensitivity analyses for MR were performed to test the robustness of causal inference.

Results

A total of 1,810 patients were included in the PPD cohort, of which 631 (34.87%) were diagnosed with PPD. Compared with the control group, PPD patients had a significantly lower level of total bilirubin (9.2 μmol/L, IQR 7.7, 11.0 in PPD; 9.7 μmol/L, IQR 8.0, 12.0 in control, P < 0.001) and direct bilirubin (2.0 μmol/L, IQR 1.6, 2.6 in PPD; 2.2 μmol/L, IQR 1.7, 2.9 in control, P < 0.003). The prediction model identified eight independent predictive factors of PPD, in which elevated total bilirubin served as a protective factor (OR = 0.94, 95% CI 0.90-0.99, P = 0.024). In the MR analyses, genetically predicted total bilirubin was associated with decreased risk of PPD (IVW: OR = 0.86, 95% CI 0.76-0.97, P = 0.006), which remained consistent after adjusting educational attainment, income, and gestational diabetes mellitus. Conversely, there is a lack of solid evidence to support the causal relationship between PPD and bilirubin.

Conclusion

Our results suggested that decreased total bilirubin was associated with the incidence of PPD. Future studies are warranted to investigate its potential mechanisms and illuminate the pathogenesis of PPD.

Ginsenosides Rg1 and Rg2 Activate Autophagy and Attenuate Oxidative Stress in Neuroblastoma Cells Overexpressing Aβ(1-42)

Alzheimer's disease is a neurodegeneration with protein deposits, altered proteolysis, and inflammatory and oxidative processes as major hallmarks. Despite the continuous search for potential therapeutic treatments, no cure is available to date. The use of natural molecules as adjuvants in the treatment of Alzheimer's disease is a very promising strategy. In this regard, ginsenosides from ginseng root show a variety of biological effects. Here, we dissected the role of ginsenosides Rg1 and Rg2 in modulating autophagy and oxidative stress in neuroblastoma cells overexpressing Aβ(1-42). Key hallmarks of these cellular processes were detected through immunomethods and fluorometric assays. Our findings indicate that ginsenosides are able to upregulate autophagy in neuronal cells as demonstrated by increased levels of LC3II and Beclin-1 proteins and decreased amounts of p62. Simultaneously, an activation of lysosomal hydrolases was observed. Furthermore, autophagy activation promoted the clearance of Aβ(1-42). Rg1 and Rg2 also reduced oxidative stress sources and macromolecule oxidation, promoting NRF2 nuclear translocation and the expression of antioxidant enzymes. Our data further clarify the mechanisms of action of Rg1 and Rg2, indicating new insights into their role in the management of disorders like Alzheimer's disease.

A hypoxia-related genes prognostic risk model, and mechanisms of hypoxia contributing to poor prognosis through immune microenvironment and drug resistance in acute myeloid leukemia

Objective: Acute myeloid leukemia (AML) is a malignant hematologic cancer with poor prognosis. Emerging evidence suggests a close association between AML progression and hypoxia. The purpose of this study was to establish a new risk prognostic model for AML based on hypoxia-related genes, and to explore the mechanisms by which hypoxia-related genes affect the prognosis of AML based on tumor immune microenvironment (TIME) and drug resistance. Methods: The AML patient samples obtained from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database were classified into C1 and C2 based on hypoxia-related genes, followed by analysis utilizing Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Gene Set Enrichment Analysis (GSEA). Through univariate and LASSO Cox regression analysis, the hypoxia-related hub genes 26S proteasome non-ATPase regulatory subunit 11 (PSMD11) and 26S proteasome non-ATPase regulatory subunit 14 (PSMD14) were identified to construct the model. AML patient samples were obtained from the TARGET and The Cancer Genome Atlas (TCGA) databases, serving as the training and the validation sets, and were stratified into high-risk and low-risk group according to the median risk score. The correlations between the model and TIME and anti-tumor drugs were analysed using CIBERSORT and Genomics of Drug Sensitivity in Cancer (GDSC) databases. The expressions of PSMD11/PSMD14 in clinical samples and AML sensitive and drug-resistant cell lines were detected by Western blot and real-time PCR. Results: The C1 group with high expression of hypoxia-related genes had lower overall survival (OS). Immune-related signaling pathways were different between C1/C2, and hypoxia was positively correlated with the activation of mammalian target of rapamycin (mTOR) signaling pathway. The model had good accuracy in both the training and the validation sets. The high-risk group exhibited lower OS and TIME activity, and was more sensitive to several anti-tumor drugs. PSMD11/PSMD14 were highly expressed in relapsed patients and AML drug-resistant cell lines. Conclusion: The established novel risk prognostic model and experiment results offer valuable insights for predicting AML prognosis and guiding drug selection. It also provides a fundamental framework for the mechanisms through which hypoxia impacts AML prognosis by modulating TIME and drug resistance.

Particulate Matter Induces Oxidative Stress and Ferroptosis in Human Lung Epithelial Cells

Numerous toxicological studies have highlighted the association between urban particulate matter (PM) and increased respiratory infections and lung diseases. The adverse impact on the lungs is directly linked to the complex composition of particulate matter, initiating reactive oxygen species (ROS) production and consequent lipid peroxidation. Excessive ROS, particularly within mitochondria, can destroy subcellular organelles through various pathways. In this study, we confirmed the induction of ferroptosis, an iron-dependent cell death, upon exposure to an urban PM using RT-qPCR and signaling pathway analysis. We used KRISS CRM 109-02-004, the certified reference material for the analysis of particulate matter, produced by the Korea Research Institute of Standards and Science (KRISS). To validate that ferroptosis causes lung endothelial toxicity, we assessed intracellular mitochondrial potential, ROS overproduction, lipid peroxidation, and specific ferroptosis biomarkers. Following exposure to the urban PM, a significant increase in ROS generation and a decrease in mitochondrial potential were observed. Furthermore, it induced hallmarks of ferroptosis, including the accumulation of lipid peroxidation, the loss of antioxidant defenses, and cellular iron accumulation. In addition, the occurrence of oxidative stress as a key feature of ferroptosis was confirmed by increased expression levels of specific oxidative stress markers such as NQO1, CYP1B1, FTH1, SOD2, and NRF. Finally, a significant increase in key ferroptosis markers was observed, including xCT/SLC7A11, NQO1, TRIM16, HMOX-1, FTL, FTH1, CYP1B1, CHAC1, and GPX4. This provides evidence that elevated ROS levels induce oxidative stress, which ultimately triggers ferroptosis. In conclusion, our results show that the urban PM, KRISS CRM, induces cellular and mitochondrial ROS production, leading to oxidative stress and subsequent ferroptosis. These results suggest that it may induce ferroptosis through ROS generation and may offer potential strategies for the treatment of lung diseases.

Identification and validation of an H2AZ1-based index model: a novel prognostic tool for hepatocellular carcinoma

The H2A.Z variant histone 1 (H2AZ1) is aberrantly expressed in various tumors, correlating with an unfavorable prognosis. However, its role in hepatocellular carcinoma (HCC) remains unclear. We aimed to elucidate the pathways affected by H2AZ1 and identify promising therapeutic targets for HCC. Following bioinformatic analysis of gene expression and clinical data from The Cancer Genome Atlas and Gene Expression Omnibus database, we found 6,344 dysregulated genes related to H2AZ1 overexpression in HCC tissues (P < 0.05). We performed weighted gene co-expression network analysis to identify the gene module most related to H2AZ1. The H2AZ1-based index was further developed using Cox regression analysis, which revealed that the poor prognosis in the high H2AZ1-based index group could be attributed to elevated tumor stemness (P < 0.05). Moreover, the clinical model showed good prognostic potential (AUC > 0.7). We found that H2AZ1 knockdown led to reduced superoxide dismutase (SOD) activity, elevated malondialdehyde (MDA) levels, and increased apoptosis rate in tumor cells (P < 0.001). Thus, we developed an H2AZ1-based index model with the potential to predict the prognosis of patients with HCC. Our findings provide initial evidence that H2AZ1 overexpression plays a pivotal role in HCC initiation and progression.