Phospholipids with two polyunsaturated fatty acyl tails promote ferroptosis.

Phospholipids containing a single polyunsaturated fatty acyl tail (PL-PUFA1s) are considered the driving force behind ferroptosis, whereas phospholipids with diacyl-PUFA tails (PL-PUFA2s) have been rarely characterized. Dietary lipids modulate ferroptosis, but the mechanisms governing lipid metabolism and ferroptosis sensitivity are not well understood. Our research revealed a significant accumulation of diacyl-PUFA phosphatidylcholines (PC-PUFA2s) following fatty acid or phospholipid treatments, correlating with cancer cell sensitivity to ferroptosis. Depletion of PC-PUFA2s occurred in aging and Huntington's disease brain tissue, linking it to ferroptosis. Notably, PC-PUFA2s interacted with the mitochondrial electron transport chain, generating reactive oxygen species (ROS) for initiating lipid peroxidation. Mitochondria-targeted antioxidants protected cells from PC-PUFA2-induced mitochondrial ROS (mtROS), lipid peroxidation, and cell death. These findings reveal a critical role for PC-PUFA2s in controlling mitochondria homeostasis and ferroptosis in various contexts and explain the ferroptosis-modulating mechanisms of free fatty acids. PC-PUFA2s may serve as diagnostic and therapeutic targets for modulating ferroptosis.

7-Dehydrocholesterol dictates ferroptosis sensitivity.

Ferroptosis, a form of regulated cell death that is driven by iron-dependent phospholipid peroxidation, has been implicated in multiple diseases, including cancer1-3, degenerative disorders4 and organ ischaemia-reperfusion injury (IRI)5,6. Here, using genome-wide CRISPR-Cas9 screening, we identified that the enzymes involved in distal cholesterol biosynthesis have pivotal yet opposing roles in regulating ferroptosis through dictating the level of 7-dehydrocholesterol (7-DHC)-an intermediate metabolite of distal cholesterol biosynthesis that is synthesized by sterol C5-desaturase (SC5D) and metabolized by 7-DHC reductase (DHCR7) for cholesterol synthesis. We found that the pathway components, including MSMO1, CYP51A1, EBP and SC5D, function as potential suppressors of ferroptosis, whereas DHCR7 functions as a pro-ferroptotic gene. Mechanistically, 7-DHC dictates ferroptosis surveillance by using the conjugated diene to exert its anti-phospholipid autoxidation function and shields plasma and mitochondria membranes from phospholipid autoxidation. Importantly, blocking the biosynthesis of endogenous 7-DHC by pharmacological targeting of EBP induces ferroptosis and inhibits tumour growth, whereas increasing the 7-DHC level by inhibiting DHCR7 effectively promotes cancer metastasis and attenuates the progression of kidney IRI, supporting a critical function of this axis in vivo. In conclusion, our data reveal a role of 7-DHC as a natural anti-ferroptotic metabolite and suggest that pharmacological manipulation of 7-DHC levels is a promising therapeutic strategy for cancer and IRI.

Ferroptosis: Biology and Role in Gastrointestinal Disease.

Ferroptosis is a form of nonapoptotic cell death that involves iron-dependent phospholipid peroxidation induced by accumulation of reactive oxygen species, and results in plasma membrane damage and the release of damage-associated molecular patterns. Ferroptosis has been implicated in aging and immunity, as well as disease states including intestinal and liver conditions and cancer. To date, several ferroptosis-associated genes and pathways have been implicated in liver disease. Although ferroptotic cell death is associated with dysfunction of the intestinal epithelium, the underlying molecular basis is poorly understood. As the mechanisms regulating ferroptosis become further elucidated, there is clear potential to use ferroptosis to achieve therapeutic benefit.

NBR1-mediated autophagic degradation of caspase 8 protects vascular endothelial cells against arsenite-induced apoptotic cell death.

Vascular endothelial cells play a critical role in maintaining the health of blood vessels, but dysfunction can lead to cardiovascular diseases. The impact of arsenite exposure on cardiovascular health is a significant concern due to its potential adverse effects. This study aims to explore how NBR1-mediated autophagy in vascular endothelial cells can protect against oxidative stress and apoptosis induced by arsenite. Initially, our observations revealed that arsenite exposure increased oxidative stress and triggered apoptotic cell death in human umbilical vein endothelial cells (HUVECs). However, treatment with the apoptosis inhibitor Z-VAD-FMK notably reduced arsenite-induced apoptosis. Additionally, arsenite activated the autophagy pathway and enhanced autophagic flux in HUVECs. Interestingly, inhibition of autophagy exacerbated arsenite-induced apoptotic cell death. Our findings also demonstrated the importance of autophagy receptor NBR1 in arsenite-induced cytotoxicity, as it facilitated the recruitment of caspase 8 to autophagosomes for degradation. The protective effect of NBR1 against arsenite-induced apoptosis was compromised when autophagy was inhibited using pharmacological inhibitors or through genetic knockdown of essential autophagy genes. Conversely, overexpression of NBR1 facilitated caspase 8 degradation and reduced apoptotic cell death in arsenite-treated HUVECs. In conclusion, our study highlights the vital role of NBR1-mediated autophagic degradation of caspase 8 in safeguarding vascular endothelial cells from arsenite-induced oxidative stress and apoptotic cell death. Targeting this pathway could offer a promising therapeutic approach to mitigate cardiovascular diseases associated with arsenite exposure.

Blockade of endothelial adenosine receptor 2 A suppresses atherosclerosis in vivo through inhibiting CREB-ALK5-mediated endothelial to mesenchymal transition.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and morbidity and mortality rates continue to rise. Atherosclerosis constitutes the principal etiology of CVDs. Endothelial injury, inflammation, and dysfunction are the initiating factors of atherosclerosis. Recently, we reported that endothelial adenosine receptor 2 A (ADORA2A), a G protein-coupled receptor (GPCR), plays critical roles in neovascularization disease and cerebrovascular disease. However, the precise role of endothelial ADORA2A in atherosclerosis is still not fully understood. Here, we showed that ADORA2A expression was markedly increased in the aortic endothelium of humans with atherosclerosis or Apoe-/- mice fed a high-cholesterol diet. In vivo studies unraveled that endothelial-specific Adora2a deficiency alleviated endothelial-to-mesenchymal transition (EndMT) and prevented the formation and instability of atherosclerotic plaque in Apoe-/- mice. Moreover, pharmacologic inhibition of ADORA2A with KW6002 recapitulated the anti-atherogenic phenotypes observed in genetically Adora2a-deficient mice. In cultured human aortic endothelial cells (HAECs), siRNA knockdown of ADORA2A or KW6002 inhibition of ADORA2A decreased EndMT, whereas adenoviral overexpression of ADORA2A induced EndMT. Mechanistically, ADORA2A upregulated ALK5 expression via a cAMP/PKA/CREB axis, leading to TGFß-Smad2/3 signaling activation, thereby promoting EndMT. In conclusion, these findings, for the first time, demonstrate that blockade of ADORA2A attenuated atherosclerosis via inhibition of EndMT induced by the CREB1-ALK5 axis. This study discloses a new link between endothelial ADORA2A and EndMT and indicates that inhibiting endothelial ADORA2A could be an effective novel strategy for the prevention and treatment of atherosclerotic CVDs.

Intramyocardial delivery of injectable hydrogel with arctigenin alleviated myocardial ischemia-reperfusion injury in rats.

Arctigenin belongs to a major bioactive component of Fructus arctii and has been found with cardioprotective effects on rats with ischemia‒reperfusion (I/R) injury. The application of arctigenin is limited due to poor water solubility and low bioavailability. Hydrogel drug delivery systems can improve the efficacy and safety of drugs, increase drug utilization, and reduce side effects. We hypothesized that hydrogels containing arctigenin would facilitate the effect of arctigenin and alleviate I/R injury in the rat heart. Presently, adult Sprague-Dawley (SD) rats were subjected to 1 h of I/R injury, then hydrogels comprising arctigenin were implanted into the myocardium of rats. Triphenyl tetrazolium chloride staining, hematoxylin-eosin staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining and Western blot were performed for evaluating the infarct size, histopathological, and vital protein alterations of hearts. It was discovered that the hydrogel combined with arctigenin abated apoptosis and reduced infarct size. In addition, the results of echocardiography and Masson staining suggested that the hydrogel with arctigenin improved cardiac function, restrained myocardial fibrosis, and activated AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1). Collectively, the injectable hydrogel delivery system enhances the effect of arctigenin, which may play a protective role in I/R injury by activating AMPK and SIRT1.

Carnosol prevents cardiac remodeling and ventricular arrhythmias in pressure overload-induced heart failure mice.

Cardiac remodeling is a commonly observed pathophysiological phenomenon associated with the progression of heart failure in various cardiovascular disorders. Carnosol, a phenolic compound extracted from rosemary, possesses noteworthy pharmacological properties including anti-inflammatory, antioxidant, and anti-apoptotic activities. Considering the pivotal involvement of inflammation, oxidative stress, and apoptosis in cardiac remodeling, the present study aims to assess the effects of carnosol on cardiac remodeling and elucidate the underlying mechanisms. In an in vivo model, cardiac remodeling was induced by performing transverse aortic constriction (TAC) surgery on mice, while an in vitro model was established by treating neonatal rat cardiomyocytes (NRCMs) with Ang II. Our results revealed that carnosol treatment effectively ameliorated TAC-induced myocardial hypertrophy and fibrosis, thereby attenuating cardiac dysfunction in mice. Moreover, carnosol improved cardiac electrical remodeling and restored connexin 43 expression, thereby reducing the vulnerability to ventricular fibrillation (VF). Furthermore, carnosol significantly reduced Ang II-induced cardiomyocyte hypertrophy in NRCMs and alleviated the upregulation of hypertrophy and fibrosis markers. Both in vivo and in vitro models of cardiac remodeling exhibited the anti-inflammatory, anti-oxidative, and anti-apoptotic effects of carnosol. Mechanistically, these effects were mediated through the Sirt1/PI3K/AKT pathway, as the protective effects of carnosol were abrogated upon inhibition of Sirt1 or activation of the PI3K/AKT pathway. In summary, our study suggests that carnosol prevents cardiac structural and electrical remodeling by regulating the anti-inflammatory, anti-oxidative, and anti-apoptotic effects mediated by Sirt1/PI3K/AKT signaling pathways, thereby alleviating heart failure and VF.

When CDK4/6i meets GPX4i: Stop dividing to die iron hard.

In this issue of Cell Chemical Biology, Rodencal et al.1 report that cell-cycle arrest by p53 stabilizers or CDK4/6 inhibitors (CDK4/6i) can lead to phospholipid remodeling and hence sensitize cancer cells to GPX4 inhibitor (GPX4i)-triggered ferroptosis. This study suggests a novel cancer therapeutic strategy combining CDK4/6i with GPX4i.

GAS41 modulates ferroptosis by anchoring NRF2 on chromatin.

YEATS domain-containing protein GAS41 is a histone reader and oncogene. Here, through genome-wide CRISPR-Cas9 screenings, we identify GAS41 as a repressor of ferroptosis. GAS41 interacts with NRF2 and is critical for NRF2 to activate its targets such as SLC7A11 for modulating ferroptosis. By recognizing the H3K27-acetylation (H3K27-ac) marker, GAS41 is recruited to the SLC7A11 promoter, independent of NRF2 binding. By bridging the interaction between NRF2 and the H3K27-ac marker, GAS41 acts as an anchor for NRF2 on chromatin in a promoter-specific manner for transcriptional activation. Moreover, the GAS41-mediated effect on ferroptosis contributes to its oncogenic role in vivo. These data demonstrate that GAS41 is a target for modulating tumor growth through ferroptosis. Our study reveals a mechanism for GAS41-mediated regulation in transcription by anchoring NRF2 on chromatin, and provides a model in which the DNA binding activity on chromatin by transcriptional factors (NRF2) can be directly regulated by histone markers (H3K27-ac).

Association between protein-to-energy ratio and overweight/obesity in children and adolescents in the United States: a cross-sectional study based on NHANES.

Background: The dietary protein proportion may be crucial in triggering overweight and obesity among children and adolescents. Methods: Cross-sectional data from 4,336 children and adolescents who participated in the National Health and Nutrition Survey (NHANES) between 2011 and March 2020 were analyzed. Multivariate logistic regression was used to calculate odds ratio (OR) and 95% confidence interval (CI). Restricted cubic splines assessed the nonlinear relationships between dietary protein intake and the prevalence of overweight and obesity. Results: Adjusted logistic regression models showed that each 1% increase in dietary protein proportion was associated with a 4% higher risk of overweight and obesity (OR = 1.04, 95% CI: 1.01-1.07). A nonlinear relationship was noted in children aged 6-11 years (P < 0.05), as demonstrated by restricted cubic spline analysis. After dividing dietary protein intake into quartiles, the highest quartile had an adjusted OR of 2.07 (95% CI: 1.35, 3.16, P = 0.001) compared to the lowest, among children aged 6-11 years. Conclusion: Dietary protein intake is positively linked to overweight and obesity in American children, irrespective of individual characteristics and total energy consumption.

Diagnostic Performance of Fractional Flow Reserve Derived From Coronary CT Angiography: The ACCURATE-CT Study.

BACKGROUND: ArteryFlow Technology (AccuFFRct) is a novel noninvasive method for calculating fractional flow reserve (FFR) from coronary computed tomography angiography (CCTA). The accuracy of AccuFFRct has not been adequately assessed. OBJECTIVES: This study sought to evaluate the diagnostic performance of AccuFFRct in detecting lesion-specific ischemia. METHODS: This prospective study enrolled 339 patients with 404 vessels. CCTA-derived FFR was calculated using an on-site computational fluid dynamics-based method and compared with invasive FFR. The performance of AccuFFRct was comprehensively analyzed in all lesions and subgroups, including "gray zone" lesions, various lesion classifications, clinical presentations, stenosis severities, and lesion locations. RESULTS: Using FFR ≤0.80 as a reference standard, the overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for AccuFFRct were 90.6% (95% CI: 87.3%-93.3%), 90.9% (95% CI: 85.1%-94.9%), 90.4% (95% CI: 86.1%-93.8%), 85.3% (95% CI: 79.8%-89.5%), and 94.2% (95% CI: 90.8%-96.4%), respectively. Good correlation and agreement were found between the computed AccuFFRct and measured FFR. AccuFFRct showed superior discrimination ability to CCTA (AUC: 0.93 [95% CI: 0.89-0.95] vs 0.77 [95% CI: 0.72-0.81]; P < 0.001) and quantitative coronary angiography (AUC: 0.93 [95% CI: 0.89-0.95] vs 0.89 [95% CI: 0.85-0.92]; P = 0.048) for identifying functionally significant stenosis. Notably, AccuFFRct maintained high diagnostic accuracy across the spectrum of lesion classifications, clinical presentations, stenosis severities, lesion locations, and in the gray zone. Furthermore, in the cohort with ≥70% stenosis, AccuFFRct could significantly reduce the rate of un-necessary invasive tests (33.1% vs 6.6%; P < 0.001). CONCLUSIONS: The study confirms the potential of AccuFFRct as a noninvasive alternative to invasive FFR for detecting ischemia in coronary artery disease and to risk stratify patients. The results highlight AccuFFRct's robust diagnostic ability across a wide range of lesion classifications, clinical presentations, stenosis severities, lesion locations, and in the gray zone. (Diagnostic Performance of Fractional Flow Reserve Derived From Coronary CT Angiography [ACCURATE-CT]; NCT04426396).

COVID-19 in Systemic Lupus Erythematosus patients treated with belimumab: a retrospective clinical study.

BACKGROUND: Routine use of immunosuppressive agents in systemic lupus erythematosus (SLE) patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) potentially increases the risk of adverse outcomes. belimumab, a monoclonal antibody for the treatment of SLE, remains untested for its specific impact on coronavirus disease 2019 (COVID-19) symptoms in these patients. Here, this research investigated the effect of belimumab on COVID-19 symptoms in SLE patients infected with SARS-CoV-2. METHODS: This study enrolled SLE patients who underwent treatment with belimumab. After thorough screening based on the inclusion and exclusion criteria, data pertaining to COVID-19 for both the participants and their cohabitants were obtained through telephone follow-up. The potential impact of belimumab on COVID-19 was evaluated by comparing COVID-19 symptoms and medication use across various groups to investigate the association between belimumab treatment and COVID-19 in SLE. RESULTS: This study involved 123 SLE patients, of whom 89.4% tested positive for SARS-CoV-2. Among cohabitants of SLE patients, the SARS-CoV-2 positive rate was 87.2% (p = 0.543). Patients treated with belimumab exhibited a lower incidence of multiple COVID-19 symptoms than their cohabitating counterparts (p < 0.001). This protective effect was found to be partially related to the time of last belimumab administration. Among those with COVID-19, 30 patients opted to discontinue their anti-SLE drugs, and among them, 53% chose to discontinue belimumab. Discontinuing drugs did not increase the risk of hospitalization due to SARS-CoV-2 infection. CONCLUSION: This study concluded that treatment with belimumab did not increase susceptibility to COVID-19 and beneficially alleviated the symptoms of COVID-19.

SUMOylation modification of FTO facilitates oxidative damage response of arsenic by IGF2BP3 in an m6A-dependent manner.

N6-methyladenosine (m6A) is the most common form of internal post-transcriptional methylation observed in eukaryotic mRNAs. The abnormally increased level of m6A within the cells can be catalyzed by specific demethylase fat mass and obesity-associated protein (FTO) and stay in a dynamic and reversible state. However, whether and how FTO regulates oxidative damage via m6A modification remain largely unclear. Herein, by using both in vitro and in vivo models of oxidative damage induced by arsenic, we demonstrated for the first time that exposure to arsenic caused a significant increase in SUMOylation of FTO protein, and FTO SUMOylation at lysine (K)- 216 site promoted the down-regulation of FTO expression in arsenic target organ lung, and therefore, remarkably elevating the oxidative damage via an m6A-dependent pathway by its specific m6A reader insulin-like growth factor-2 mRNA-binding protein-3 (IGF2BP3). Consequently, these findings not only reveal a novel mechanism underlying FTO-mediated oxidative damage from the perspective of m6A, but also imply that regulation of FTO SUMOylation may serve as potential approach for treatment of oxidative damage.

Protective effects of patchouli alcohol against DSS-induced ulcerative colitis.

Patchouli alcohol (PA) is a widely used pharmaceutical ingredient in various Chinese traditional herbal medicine (THM) formulations, known for its modulatory effects on the gut microbiota. The present study investigated PA's anti-inflammatory and regulatory effects on gut microbiota and its mode of action (MOA). Based on the assessments of ulcerative colitis (UC) symptoms, PA exhibited promising preventions against inflammatory response. In accordance, the expressions of pro-inflammatory factors, including interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, and chemokine ligand 5 were significantly attenuated under PA treatment. Furthermore, PA enhanced the intestinal barrier damage caused by dextran sodium sulfate (DSS). Interestingly, PA exhibited negligible inventions on DSS-induced gut microbiota dysbiosis. PA did not affect the diversity of the DSS gut microbiota, it did alter the composition, as evidenced by a significant increase in the Firmicutes-Bacteroidetes (F/B) ratio. Finally, the MOA of PA against inflammation in DSS-treated mice was addressed by suppressing the expressions of heme oxygenase-1 (HO-1) and inducible nitric oxide synthase (iNOS). In conclusion, PA prevented inflammatory response in the DSS-induced UC mice model via directly suppressing HO-1 and iNOS-associated antioxidant signal pathways, independent of its effects on gut microbiota composition.

PHLDA2-mediated phosphatidic acid peroxidation triggers a distinct ferroptotic response during tumor suppression.

Although the role of ferroptosis in killing tumor cells is well established, recent studies indicate that ferroptosis inducers also sabotage anti-tumor immunity by killing neutrophils and thus unexpectedly stimulate tumor growth, raising a serious issue about whether ferroptosis effectively suppresses tumor development in vivo. Through genome-wide CRISPR-Cas9 screenings, we discover a pleckstrin homology-like domain family A member 2 (PHLDA2)-mediated ferroptosis pathway that is neither ACSL4-dependent nor requires common ferroptosis inducers. PHLDA2-mediated ferroptosis acts through the peroxidation of phosphatidic acid (PA) upon high levels of reactive oxygen species (ROS). ROS-induced ferroptosis is critical for tumor growth in the absence of common ferroptosis inducers; strikingly, loss of PHLDA2 abrogates ROS-induced ferroptosis and promotes tumor growth but has no obvious effect in normal tissues in both immunodeficient and immunocompetent mouse tumor models. These data demonstrate that PHLDA2-mediated PA peroxidation triggers a distinct ferroptosis response critical for tumor suppression and reveal that PHLDA2-mediated ferroptosis occurs naturally in vivo without any treatment from ferroptosis inducers.

The burden and management competency of cardiomyopathies in China: a nationwide survey study.

Background: The public health burden of cardiomyopathies and competency in their management by health agencies in China are not well understood. Methods: This study adopted a multi-stage sampling method for hospital selection. In the first stage, nationwide tertiary hospital recruitment was performed. As a result, 88 hospitals with the consent of the director of cardiology and access to an established electronic medical records system, were recruited. In the second stage, we sampled 66 hospitals within each geographic-economic stratification through a random sampling process. Data on (1) the outpatient and inpatient visits for cardiomyopathies between 2017 and 2021 and (2) the competency in the management of patients with cardiomyopathies, were collected. The competency of a hospital to provide cardiomyopathy care was evaluated using a specifically devised scale. Findings: The outpatient and inpatient visits for cardiomyopathies increased between 2017 and 2021 by 38.6% and 33.0%, respectively. Most hospitals had basic facilities for cardiomyopathy assessment. However, access to more complex procedures was limited, and the integrated management pathway needs improvement. Only 4 (6.1%) of the 66 participating hospitals met the criteria for being designated as a comprehensive cardiomyopathy center, and only 29 (43.9%) could be classified as a primary cardiomyopathy center. There were significant variations in competency between hospitals with different administrative and economic levels. Interpretation: The health burden of cardiomyopathies has increased significantly between 2017 and 2021 in China. Although most tertiary hospitals in China can offer basic cardiomyopathy care, more advanced facilities are not yet universally available. Moreover, inconsistencies in the management of cardiomyopathies across hospitals due to differing administrative and economic levels warrants a review of the nation allocation of medical resources. Funding: This work was supported by the Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences (2023-I2M-1-001) and the National High Level Hospital Clinical Research Funding (2022-GSP-GG-17).

A guideline on the molecular ecosystem regulating ferroptosis.

Ferroptosis, an intricately regulated form of cell death characterized by uncontrolled lipid peroxidation, has garnered substantial interest since this term was first coined in 2012. Recent years have witnessed remarkable progress in elucidating the detailed molecular mechanisms that govern ferroptosis induction and defence, with particular emphasis on the roles of heterogeneity and plasticity. In this Review, we discuss the molecular ecosystem of ferroptosis, with implications that may inform and enable safe and effective therapeutic strategies across a broad spectrum of diseases.

Ferroptosis in health and disease.

Ferroptosis is a pervasive non-apoptotic form of cell death highly relevant in various degenerative diseases and malignancies. The hallmark of ferroptosis is uncontrolled and overwhelming peroxidation of polyunsaturated fatty acids contained in membrane phospholipids, which eventually leads to rupture of the plasma membrane. Ferroptosis is unique in that it is essentially a spontaneous, uncatalyzed chemical process based on perturbed iron and redox homeostasis contributing to the cell death process, but that it is nonetheless modulated by many metabolic nodes that impinge on the cells' susceptibility to ferroptosis. Among the various nodes affecting ferroptosis sensitivity, several have emerged as promising candidates for pharmacological intervention, rendering ferroptosis-related proteins attractive targets for the treatment of numerous currently incurable diseases. Herein, the current members of a Germany-wide research consortium focusing on ferroptosis research, as well as key external experts in ferroptosis who have made seminal contributions to this rapidly growing and exciting field of research, have gathered to provide a comprehensive, state-of-the-art review on ferroptosis. Specific topics include: basic mechanisms, in vivo relevance, specialized methodologies, chemical and pharmacological tools, and the potential contribution of ferroptosis to disease etiopathology and progression. We hope that this article will not only provide established scientists and newcomers to the field with an overview of the multiple facets of ferroptosis, but also encourage additional efforts to characterize further molecular pathways modulating ferroptosis, with the ultimate goal to develop novel pharmacotherapies to tackle the various diseases associated with - or caused by - ferroptosis.

The disulphide cleavage derivative (C42-4) of 11'-deoxyverticillin A (C42) fails to induce apoptosis and genomic instability in HeLa cells.

Our previous study revealed 11'-deoxyverticillin A (C42), a natural product isolated from the Ophiocordyceps-associated fungus Clonostachys rogersoniana and a member of the epipolythiodioxopiperazines (ETPs), induced both apoptosis and autophagy in HCT116 cells; however, the role of disulphide/polysulphide bridges of C42 in the regulation of autophagy remains unexplored. Here, we revealed that C42 activated both caspase-dependent apoptosis and autophagy in HeLa cells, whereas its disulphide cleavage derivative C42-4 failed to induce the cleavage of both caspase-3 and PARP-1. In contrast, both C42 and C42-4 increased the formation of autophagosomes, punctate staining of LC3, and the ratio of LC3-II to actin, suggesting that disulphide/polysulphide bridges are dispensable for the induction of the autophagic process. Moreover, we found that C42 but not C42-4 led to nuclear instability by increasing the formation of micronuclei and expression of phosphorylated histone H2AX (γ-H2AX), a widely used marker for DNA double strand breaks (DSBs), while Rad51, a protein pivotal for DNA repair, was decreased upon challenge with C42. These results demonstrate that the disulphide bonds in ETPs play an essential role in the induction of caspase-dependent apoptosis and nuclear stability.

The overexpression of lncRNA H19 as a diagnostic marker for coronary artery disease

SUMMARY OBJECTIVE: Our study aimed to investigate the diagnostic value of lncRNA H19 for coronary artery disease (CAD) and to explore its possible mechanisms. Methods: A total of 30 CAD patients and 30 healthy individuals, as well as patients with different cardiovascular diseases, were included in this study. Blood was drawn from each participant to prepare serum samples, and the expression of lncRNA H19 was detected using qRT-PCR. The ROC curve analysis was used to analyze the diagnostic value of H19 for CAD. The effects of patients' basic information and lifestyle on H19 expression were analyzed. The plasma level of TGF-β1 was measured by ELISA. The H19 overexpression in the human primary coronary artery endothelial cell (HCAEC) line was constructed, and the effects of H19 overexpression on the TGF-β1 expression were analyzed using Western blot. The results of H19 expression were specifically upregulated in patients with CAD but not in healthy individuals and patients with other types of cardiovascular diseases. The ROC curve analysis showed that the H19 expression level could be used to predict CAD accurately. Gender, age, and patients' lifestyle had no significant effects on H19 expression, but H19 expression was higher in patients with a longer course of disease in comparison with the controls. H19 expression was positively correlated with the serum level of TGF-β1, and H19 overexpression significantly increased TGF-β1 protein level in HCAEC. Conclusion: H19 overexpression participates in the pathogenesis of CAD by increasing the expression level of TGF-β1, and H19 expression level may serve as a diagnostic marker for CAD.

RESUMO OBJETIVO Nosso estudo teve como objetivo investigar o valor diagnóstico do lncRNA H19 para doença arterial coronariana (DAC) e explorar os possíveis mecanismos. Métodos Um total de 30 pacientes com DAC e 30 pessoas saudáveis, bem como pacientes com diferentes doenças cardiovasculares foram incluídos neste estudo. O sangue foi extraído de cada participante para preparar amostras de soro e a expressão de lncRNA H19 foi detectada por qRT-PCR. A análise da curva ROC foi utilizada para analisar o valor diagnóstico de H19 para DAC. Efeitos da informação básica dos pacientes e estilo de vida na expressão de H19 foram analisados. O nível plasmático de TGF-β1 foi medido por ELISA. A linha de células endoteliais da artéria coronária primária (HCAEC) humana de sobre-expressão de H19 foi construída e os efeitos da sobre-expressão de H19 na expressão de TGF-β1 foram analisados por Western blot. Resultados A expressão de H19 foi especificamente regulada positivamente em pacientes com DAC, mas não em pessoas saudáveis e em pacientes com outros tipos de doenças cardiovasculares. A análise da curva ROC mostrou que o nível de expressão de H19 pode ser usado para prever com precisão a DAC. Sexo, idade e estilo de vida dos pacientes não têm efeitos significativos sobre a expressão de H19, mas a expressão de H19 foi maior em pacientes com curso mais longo da doença em comparação com os controles. A expressão de H19 correlacionou-se positivamente com o nível sérico de TGF-β1 e a superexpressão de H19 aumentou significativamente o nível de proteína de TGF-β1 em HCAEC. Conclusão A superexpressão de H19 participa da patogênese da DAC aumentando o nível de expressão de TGF-β1 e o nível de expressão de H19 pode servir como marcador diagnóstico de DAC.