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Aiming at the problem of class imbalance in the wind turbine blade bolts operation-monitoring dataset, a fault detection method for wind turbine blade bolts based on Gaussian Mixture Model-Synthetic Minority Oversampling Technique-Gaussian Mixture Model (GSG) combined with Cost-Sensitive LightGBM (CS-LightGBM) was proposed. Since it is difficult to obtain the fault samples of blade bolts, the GSG oversampling method was constructed to increase the fault samples in the blade bolt dataset. The method obtains the optimal number of clusters through the BIC criterion, and uses the GMM based on the optimal number of clusters to optimally cluster the fault samples in the blade bolt dataset. According to the density distribution of fault samples in inter-clusters, we synthesized new fault samples using SMOTE in an intra-cluster. This retains the distribution characteristics of the original fault class samples. Then, we used the GMM with the same initial cluster center to cluster the fault class samples that were added to new samples, and removed the synthetic fault class samples that were not clustered into the corresponding clusters. Finally, the synthetic data training set was used to train the CS-LightGBM fault detection model. Additionally, the hyperparameters of CS-LightGBM were optimized by the Bayesian optimization algorithm to obtain the optimal CS-LightGBM fault detection model. The experimental results show that compared with six models including SMOTE-LightGBM, CS-LightGBM, K-means-SMOTE-LightGBM, etc., the proposed fault detection model is superior to the other comparison methods in the false alarm rate, missing alarm rate and F1-score index. The method can well realize the fault detection of large wind turbine blade bolts.
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As one of the key components of wind turbines, gearboxes are under complex alternating loads for a long time, and the safety and reliability of the whole machine are often affected by the failure of internal gears and bearings. Aiming at the difficulty of optimizing the parameters of wind turbine gearbox fault detection models based on extreme random forest, a fault detection model with extreme random forest optimized by the improved butterfly optimization algorithm (IBOA-ERF) is proposed. The algebraic sum of the false alarm rate and the missing alarm rate of the fault detection model is constructed as the fitness function, and the initial position and position update strategy of the individual are improved. A chaotic mapping strategy is introduced to replace the original population initialization method to enhance the randomness of the initial population distribution. An adaptive inertia weight factor is proposed, combined with the landmark operator of the pigeon swarm optimization algorithm to update the population position iteration equation to speed up the convergence speed and improve the diversity and robustness of the butterfly optimization algorithm. The dynamic switching method of local and global search stages is adopted to achieve dynamic balance between global exploration and local search, and to avoid falling into local optima. The ERF fault detection model is trained, and the improved butterfly optimization algorithm is used to obtain optimal parameters to achieve fast response of the proposed model with good robustness and generalization under high-dimensional data. The experimental results show that, compared with other optimization algorithms, the proposed fault detection method of wind turbine gearboxes has a lower false alarm rate and missing alarm rate.
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It is difficult to optimize the fault model parameters when Extreme Random Forest is used to detect the electric pitch system fault model of the double-fed wind turbine generator set. Therefore, Extreme Random Forest which was optimized by improved grey wolf algorithm (IGWO-ERF) was proposed to solve the problems mentioned above. First, IGWO-ERF imports the Cosine model to nonlinearize the linearly changing convergence factor α to balance the global exploration and local exploitation capabilities of the algorithm. Then, in the later stage of the algorithm iteration, α wolf generates its mirror wolf based on the lens imaging learning strategy to increase the diversity of the population and prevent local optimum of the population. The electric pitch system fault detection method of the wind turbine generator set sets the generator power of the variable pitch system as the main state parameter. First, it uses the Pearson correlation coefficient method to eliminate the features with low correlation with the electric pitch system generator power. Then, the remaining features are ranked by the importance of the RF features. Finally, the top N features are selected to construct the electric pitch system fault data set. The data set is divided into a training set and a test set. The training set is used to train the proposed fault detection model, and the test set is used for testing. Compared with other parameter optimization algorithms, the proposed method has lower FNR and FPR in the electric pitch system fault detection of the wind turbine generator set.
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Junctophilins (JPs) emerge to play key role in human pathophysiology. This family includes four subtypes (JP1-4), which are differentially detected in excitable cells. Previous work demonstrated the knockout of JPs that seriously damage physiological functions in skeletal muscle, cardiac, and neurons. Here, we summarize latest papers on the essential function of JPs in some Ca2+ -related diseases and neurological diseases, such as primary muscle disease, cardiomyopathies, Type 2 diabetes, gastrointestinal cancer, Huntington's disease-like 2, and Charcot-Marie-Tooth disease. Growing evidence suggests that targeting JPs might be a promising therapeutic approach to achieve better clinical efficacy in Ca 2+ -related diseases and neurological diseases.
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Proteínas de la Membrana/fisiología , Animales , Señalización del Calcio/fisiología , Diabetes Mellitus Tipo 2/metabolismo , Neoplasias Gastrointestinales/metabolismo , Cardiopatías/metabolismo , Humanos , Enfermedades Musculares/metabolismo , Enfermedades del Sistema Nervioso/metabolismoRESUMEN
Apelin is the endogenous ligand for the G protein-coupled receptor APJ. Both apelin and APJ receptor are distributed in vascular smooth muscle cells (VSMCs) and play important roles in the cardiovascular system. Our previous reports have indicated that apelin-13 promoted the proliferation of VSMCs, but its exact mechanism remains to be further explored. The results of the present study demonstrated that the Warburg effect plays a pivotal role in apelin-13-induced human aortic vascular smooth muscle cells (HA-VSMCs) proliferation. Apelin-13 promoted the expression of glucose transporter type 1 (GLUT1), pyruvate kinase 2 (PKM2), lactate dehydrogenase A (LDHA), monocarboxylate transporter 1 (MCT1), and monocarboxylate transporter 4 (MCT4) in a dose- and time-dependent manner. Moreover, apelin-13 increased the extracellular, intracellular lactate level, and decreased adenosine triphosphate level in HA-VSMCs. Furthermore, siRNA-PKM2 reversed extracellular and intracellular lactate generation and inhibited the proliferation of HA-VSMCs induced by apelin-13. Downregulation of LDHA also significantly prevented extracellular and intracellular lactate generation and inhibited the proliferation of HA-VSMCs induced by apelin-13. Taken together, our results demonstrated a novel mechanism for HA-VSMCs proliferation induced by apelin-13 via Warburg effect.
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Aberrant proliferation of vascular smooth muscle cells (VSMC) is a critical contributor to the pathogenesis of atherosclerosis (AS). Our previous studies have demonstrated that apelin-13/APJ confers a proliferative response in VSMC, however, its underlying mechanism remains elusive. In this study, we aimed to investigate the role of mitophagy in apelin-13-induced VSMC proliferation and atherosclerotic lesions in apolipoprotein E knockout (ApoE-/-) mice. Apelin-13 enhances human aortic VSMC proliferation and proliferative regulator proliferating cell nuclear antigen expression in dose and time-dependent manner, while is abolished by APJ antagonist F13A. We observe the engulfment of damage mitochondria by autophagosomes (mitophagy) of human aortic VSMC in apelin-13 stimulation. Mechanistically, apelin-13 increases p-AMPKα and promotes mitophagic activity such as the LC3I to LC3II ratio, the increase of Beclin-1 level and the decrease of p62 level. Importantly, the expressions of PINK1, Parkin, VDAC1, and Tom20 are induced by apelin-13. Conversely, blockade of APJ by F13A abolishes these stimulatory effects. Human aortic VSMC transfected with AMPKα, PINK1, or Parkin and subjected to apelin-13 impairs mitophagy and prevents proliferation. Additional, apelin-13 not only increases the expression of Drp1 but also reduces the expressions of Mfn1, Mfn2, and OPA1. Remarkably, the mitochondrial division inhibitor-1(Mdivi-1), the pharmacological inhibition of Drp1, attenuates human aortic VSMC proliferation. Treatment of ApoE-/- mice with apelin-13 accelerates atherosclerotic lesions, increases p-AMPKα and mitophagy in aortic wall in vivo. Finally, PINK1-/- mutant mice with apelin-13 attenuates atherosclerotic lesions along with defective in mitophagy. PINK1/Parkin-mediated mitophagy promotes apelin-13-evoked human aortic VSMC proliferation by activating p-AMPKα and exacerbates the progression of atherosclerotic lesions.
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Proteínas Quinasas Activadas por AMP/metabolismo , Enfermedades de la Aorta/enzimología , Aterosclerosis/enzimología , Proliferación Celular/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Mitocondrias Musculares/efectos de los fármacos , Mitofagia/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Proteínas Quinasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/patología , Aterosclerosis/genética , Aterosclerosis/patología , Estudios de Casos y Controles , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Mitocondrias Musculares/enzimología , Mitocondrias Musculares/ultraestructura , Músculo Liso Vascular/enzimología , Músculo Liso Vascular/ultraestructura , Miocitos del Músculo Liso/enzimología , Miocitos del Músculo Liso/ultraestructura , Fosforilación , Placa Aterosclerótica , Proteínas Quinasas/deficiencia , Proteínas Quinasas/genética , Transducción de Señal , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
Nuclear receptor coactivator 4 mediated ferritinophagy is an autophagic phenomenon that specifically involves ferritin to release intracellular free iron. Ferritinophagy is implicated in maintaining efficient erythropoiesis. Notably, ferritinophagy also plays a central role in driving some pathological processes, including Parkinson's disease (PD) and urinary tract infections. Some evidence has demonstrated that ferritinophagy is critical to induce ferroptosis. Ferroptosis is a newly nonapoptotic form of cell death, characterized by the accumulation of iron-based lipid reactive oxygen species. Ferroptosis plays an important role in inhibiting some types of cancers, such as hepatocellular carcinoma, pancreatic carcinoma, prostate cancer, and breast cancer. Conversely, the activation of ferroptosis accelerates neurodegeneration diseases, including PD and Alzheimer's disease. Therefore, in this review, we summarize the regulatory mechanisms related to ferritinophagy and ferroptosis. Moreover, the distinctive effects of ferritinophagy in human erythropoiesis and some pathologies, coupled with the promotive or inhibitory role of tumorous and neurodegenerative diseases mediated by ferroptosis, are elucidated. Obviously, activating or inhibiting ferroptosis could be exploited to achieve desirable therapeutic effects on diverse cancers and neurodegeneration diseases. Interrupting ferritinophagy to control iron level might provide a potentially therapeutic avenue to suppress urinary tract infections.
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Ferritinas/metabolismo , Trastornos del Metabolismo del Hierro/metabolismo , Hierro/metabolismo , Neoplasias/metabolismo , Distrofias Neuroaxonales/metabolismo , Autofagia/genética , Eritropoyesis/genética , Ferritinas/efectos adversos , Humanos , Trastornos del Metabolismo del Hierro/genética , Trastornos del Metabolismo del Hierro/patología , Neoplasias/clasificación , Neoplasias/etiología , Neoplasias/patología , Distrofias Neuroaxonales/genética , Distrofias Neuroaxonales/patología , Coactivadores de Receptor Nuclear/genética , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Infecciones Urinarias/genética , Infecciones Urinarias/metabolismoRESUMEN
Apelin is the endogenous ligand of APJ receptor. Both monocytes (MCs) and human umbilical vein endothelial cells (HUVECs) express apelin and APJ, which play important roles in the physiological processes of atherosclerosis. Our previous research indicated that apelin-13 promoted MCs-HUVECs adhesion. Here, we further explore the mechanism responsible for MCs-HUVECs adhesion induced by apelin-13. Apelin-13 promoted reactive oxygen species (ROS) generation and NOX4 expression in HUVECs. Apelin-13 inducedautophagy, increased proteins beclin1 and LC3-II/I expression and induced autophagy flux in HUVECs, which was blocked by NAC, catalase and DPI. Autophagy flux induced by apelin-13 was inhibited by NAC and catalase but not hydroxychloroquine (HCQ). NAC, catalase, and DPI prevented apelin-13 induced ICAM-1 expression in HUVECs. Rapamycin enhanced MCs-HUVECs adhesion that was reversed by NAC, catalase, and DPI. Down-regulation of beclin1 and LC3 by siRNA blocked MCs-HUVECs adhesion. Apelin-13 induced atherosclerotic plaque and increased NOX4, LC3-II/I expression in ApoE-/-(HFD) mouse model. Our results demonstrated that apelin-13 induced MCs-HUVECs adhesion via a ROS-autophagy pathway.
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Autofagia/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Monocitos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Autofagia/fisiología , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ratones Noqueados , Monocitos/metabolismo , NADPH Oxidasas/efectos de los fármacos , NADPH Oxidasas/metabolismo , Transducción de Señal/efectos de los fármacos , Venas Umbilicales/efectos de los fármacos , Venas Umbilicales/metabolismoRESUMEN
As a frequently used neonicotinoid insecticide, imidacloprid can impair the chemoreceptive behavior of honey bees even at sublethal doses, while the physiochemical mechanism has not been further revealed. Here, multiple fluorescence spectra, thermodynamic method, and molecular docking were used to study the interaction and the functional inhibition of imidacloprid to the recombinant CSP1 protein in Asian honey bee, Apis cerana. The results showed that the fluorescence intensity (λem = 332 nm) of CSP1 could be significantly quenched by imidacloprid in a dynamic mode. During the quenching process, ΔH > 0, ΔS > 0, indicating that the acting forces of imidacloprid with CSP1 are mainly hydrophobic interactions. Synchronous fluorescence showed that the fluorescence of CSP1 was mainly derived from tryptophan, and the hydrophobicity of tryptophan decreased with the increase of imidacloprid concentration. Molecular docking predicted the optimal pose and the amino acid composition of the binding process. Circular dichroism (CD) spectra showed that imidacloprid reduced the α-helix of CSP1 and caused the extension of the CSP1 peptide chain. In addition, the binding of CSP1 to floral scent ß-ionone was inhibited by nearly 50% of the apparent association constant (KA) in the presence of 0.28-2.53 ng/bee of imidacloprid, and the inhibition rate of nearly 95% at 3.75 ng/bee of imidacloprid at sublethal dose level. This study initially revealed the molecular physiochemical mechanism that sublethal doses of neonicotinoid still interact and inhibit the physiological function of the honey bees' chemoreceptive system.
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Colinérgicos/toxicidad , Imidazoles/toxicidad , Proteínas de Insectos/química , Insecticidas/toxicidad , Nitrocompuestos/toxicidad , Norisoprenoides/química , Secuencia de Aminoácidos , Animales , Abejas/efectos de los fármacos , Abejas/fisiología , Colinérgicos/química , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Conducta Alimentaria/efectos de los fármacos , Conducta Alimentaria/fisiología , Expresión Génica , Imidazoles/química , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Insecticidas/química , Cinética , Simulación del Acoplamiento Molecular , Neonicotinoides , Nitrocompuestos/química , Norisoprenoides/antagonistas & inhibidores , Dominios Proteicos , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Espectrometría de Fluorescencia , Termodinámica , Triptófano/química , Triptófano/metabolismo , Tirosina/química , Tirosina/metabolismoAsunto(s)
Proteínas Portadoras , Proteínas de la Membrana , Estrés Oxidativo , Enfermedad de Parkinson , Hormonas Tiroideas , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/metabolismo , Humanos , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/enzimología , Hormonas Tiroideas/metabolismo , Proteínas de Unión a Hormona TiroideAsunto(s)
Mitocondrias/metabolismo , Dinámicas Mitocondriales , Procesamiento Proteico-Postraduccional , Transducción de Señal , Animales , Apoptosis , Arritmias Cardíacas/metabolismo , Carcinogénesis/metabolismo , Humanos , Lipoilación , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , Modelos Biológicos , Enfermedades Neurodegenerativas/metabolismo , Tioléster Hidrolasas/metabolismoRESUMEN
Harris hawks optimizer (HHO) is a relatively novel meta-heuristic approach that mimics the behavior of Harris hawk over the process of predating the rabbits. The simplicity and easy implementation of HHO have attracted extensive attention of many researchers. However, owing to its capability to balance between exploration and exploitation is weak, HHO suffers from low precision and premature convergence. To tackle these disadvantages, an improved HHO called VGHHO is proposed by embedding three modifications. Firstly, a novel modified position search equation in exploitation phase is designed by introducing velocity operator and inertia weight to guide the search process. Then, a nonlinear escaping energy parameter E based on cosine function is presented to achieve a good transition from exploration phase to exploitation phase. Thereafter, a refraction-opposition-based learning mechanism is introduced to generate the promising solutions and helps the swarm to flee from the local optimal solution. The performance of VGHHO is evaluated on 18 classic benchmarks, 30 latest benchmark tests from CEC2017, 21 benchmark feature selection problems, fault diagnosis problem of wind turbine and PV model parameter estimation problem, respectively. The simulation results indicate that VHHO has higher solution quality and faster convergence speed than basic HHO and some well-known algorithms in the literature on most of the benchmark and real-world problems.
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In this paper, a clean process based on the steam-mediated reactions for simultaneous HCl and KCl production using the potassium (K)-containing phosphorous rock as a precursor is proposed. Through hydrochloric acid (HCl) leaching, not only the generation of H3PO4 and CaCl2 (via further precipitation) were realized but also the acid-insoluble residue [phosphorous-rock slag (PS)] rich in elements, that is, K, Al, Si, and so on, in the form of microcline (KAlSi3O8) and quartz (SiO2) was obtained and became readily available for further HCl and KCl generation. Over 95% of the elements, that is, K, Al, and Si, come into the final products, and the overall acid consumption (based on HCl) is significantly reduced (90%) due to recovery of acids. The impacts of the key operational parameters such as temperature, duration, and reagent impregnate ratio were rigorously analyzed via a supervised machine learning approach, and the optimal conditions were determined [reaction temperature, X1, 850 °C; reaction duration, X2, 40 min; and impregnate ratio (PS over CaCl2), X3, 2.5] with approximately ±10% uncertainties. Thermodynamic analysis indicates that the introduction of steam to PS + CaCl2 not only enhances the chemical potential for the formation of HCl and KCl but also provides the transport advantage in continuously removing the generated products, that is, HCl and KCl, out of the system. Molecular simulation indicates that the presence of both steam and SiO2 in the PS matrix plays critical roles in decomposing PS + CaCl2 at high temperature. The shrinking core model shows that both the intrinsic kinetics and transport are influential with the activation energy being around 14.63 kJ/mol. The potential reaction pathway is postulated.
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Apelin is an endogenous ligand of the G protein-coupled receptor APJ. Both apelin and APJ receptors, which are expressed in vascular smooth muscle cells (VSMCs), play important roles in the cardiovascular system. Our previous studies researches indicated that mitophagy mediated apelin-13-induced VSMCs proliferation. However, little is known about how apelin-13 regulates mitophagy to participate in VSMC proliferation. The results of the present study demonstrated that mitochondrial calcium uniporter (MCU) uptake-dependent mitochondrial calcium-induced mitophagy is involved in apelin-13-induced VSMCs proliferation. Apelin-13 promoted the expression of MCU which increases mitochondrial calcium uptake. Apelin-13-induced MCU-dependent mitochondrial calcium uptake further increased mitochondrial ROS (mtROS) concentrations and promoted mitophagy, which can be evidenced through the upregulation of the Dynamin-related protein 1(Drp1), PTEN-induced kinase 1 (PINK1), and Parkin. The clearance of mtROS by Mito-TEMPO significantly reversed apelin-13-induced mitophagy. Moreover, both the Drp1 inhibitor mdivi-1 and siRNA-Drp1 inhibited apelin-13-induced mitophagy. Furthermore, the APJ receptor antagonist F13A, MCU inhibitor Ru360, mitochondria-targeted antioxidant Mito-TEMPO, Drp1 inhibitor Mdivi-1, siRNA-Drp1, siRNA-PINK1, and siRNA-Parkin inhibited the proliferation of VSMCs induced by apelin-13. In ApoE-/- mice, intraperitoneal administration of apelin-13 induced the expression of MCU, Drp1, PINK1, Parkin, and α-SMA and increased atherosclerotic plaque lesions. However, F13A and Ru360 decreased the expression of MCU, Drp1, PINK1, Parkin, and α-SMA and reduced atherosclerotic plaque lesions in ApoE-/- mice injected with apelin-13. Collectively, our results demonstrate that MCU-dependent mitochondrial calcium uptake-induced mitophagy is involved in apelin-13-stimulated VSMCs proliferation.
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Mitofagia , Placa Aterosclerótica , Animales , Apelina/farmacología , Apolipoproteínas E , Calcio , Canales de Calcio , Proliferación Celular , Péptidos y Proteínas de Señalización Intercelular , Ratones , Proteínas Mitocondriales , Músculo Liso Vascular/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Quinasas/farmacología , ARN Interferente Pequeño , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/farmacologíaRESUMEN
AIMS: Beclin1(BECN1) is known as an autophagy-related protein and the expression is promoted by apelin in lung adenocarcinoma cells, suggesting that apelin activates autophagy in lung adenocarcinoma. However, the functions of apelin-induced autophagy in lung adenocarcinoma tumorigenesis and deterioration are still unknown. Thus, this study aims to investigate the effects of apelin-induced autophagy on lung adenocarcinoma tumorigenesis and deterioration. MAIN METHODS: Protein expression of exogenous genes were detected by Western blotting analysis. Lung adenocarcinoma cell migration was assessed with cell migration assays. Autophagy was measured with quantification of GFP-LC3 or RFP-GFP-LC3 puncta using fluorescence microscopy in cells by an observed blinded to experimental condition and by western blot analysis of LC3 and p62 in cell lysates as well as autophagy flux. Immunofluorescence staining was performed in human lung adenocarcinoma A549 cells with p-cofilin antibody. The proteins expression in cancer specimens were examined with immunohistochemistry. KEY FINDINGS: Here, we reveal that apelin induces autophagy activation in lung adenocarcinoma. Apelin/APJ regulates BECN1 transcription via HIF1A. Apelin/APJ-activated autophagy promotes lung adenocarcinoma cell migration. Moreover, treatment with autophagy inhibitors significantly decreases apelin/APJ-induced lung adenocarcinoma cell migration. Evaluation of patient samples of lung adenocarcinoma reveals an association between APJ with BECN1 expression and a poor prognosis. SIGNIFICANCE: Our studies demonstrate that apelin-induced autophagy promotes lung adenocarcinoma cell migration which suggests a potential therapeutic target for lung adenocarcinoma.
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Adenocarcinoma/patología , Receptores de Apelina/metabolismo , Apelina/metabolismo , Autofagia , Neoplasias Pulmonares/patología , Metástasis de la Neoplasia , Transducción de Señal , Células A549 , Factores Despolimerizantes de la Actina/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Autofagia/genética , Beclina-1/metabolismo , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , FosforilaciónRESUMEN
The liver kinase B1 (LKB1) is an important tumor suppressor and its loss-of-function mutations are observed in around 16% of non-small cell lung cancer (NSCLC) cases. One of the main functions of LKB1 is to activate AMP-activated protein kinase (AMPK) via direct phosphorylation. Under metabolic or energy stress conditions, the LKB1-AMPK axis inhibits the anabolic pathways and activates the catabolic pathways to maintain metabolic homeostasis for cell survival. In this study, we found that LKB1-mutant NSCLC cells are particularly susceptible to cell death induced by glucose starvation, but not by other forms of starvation such as amino acid starvation or serum starvation. Reconstitution of LKB1 in LKB1-mutant cells or LKB1 knockout in LKB1-wild type cells highlighted the importance of the LKB1-AMPK axis for cell survival under glucose starvation. Mechanistically, in LKB1-mutant cells, glucose starvation elicits oxidative stress, which causes AMPK protein oxidation and inactivation, and eventually cell death. Importantly, this process could be effectively reversed and rescued by 2DG (a glucose analog capable of producing NADPH, a key antioxidant), A769662 (an allosteric AMPK activator), and N-acetyl cysteine (NAC) (a ROS scavenger), indicating the presence of a vicious circle between AMPK inactivation and ROS in LKB1-mutant NSCLC cells under glucose starvation. Our study thus elucidates the critical role of redox balance in determining the susceptibility to cell death under glucose starvation in LKB1-mutant NSCLC cells. The findings from this study reveal important clues in search of novel therapeutic strategies for LKB1-mutant NSCLC by targeting glucose metabolism and redox balance.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Glucosa , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Estrés Oxidativo/genéticaRESUMEN
AIMS: Although previous studies elaborated that selective autophagy was involved in quality control of some organelles, including nucleus, mitochondria, the endoplasmic reticulum and peroxisomes, it remained unclear whether the selective autophagy of the Golgi apparatus (Golgiphagy) existed or not. MAIN METHODS: In this study, H9c2 cells, HUVECs, HA-VSMCs and HEK293T cells were treated with autophagy inducers, Golgi stress inducers and cardiomyocytes hypertrophy stimulators. The Golgiphagy was evaluated by analysing the co-localization of Golgi markers and LC3B. Furthermore, the transmission electron microscope was used to observe the occurrence of Golgiphagy. The co-immunoprecipitation assay was used to evaluate the interaction of GOLPH3 and LC3B. KEY FINDINGS: Results showed that starvation promoted the co-localization of both GM130-positive and TGN46-positive Golgi fragments with LC3B-positive autophagosomes in H9c2 cells, HUVECs, HA-VSMCs and HEK293T cells. Transmission electron microscopy images showed that Golgi apparatus was sequestered into the autophagosomes in the starvation group. Moreover, Golgi stress inducers also facilitated the co-localization of Golgi markers and LC3B in H9c2 cells, HUVECs, HA-VSMCs and HEK293T cells. Furthermore, cardiomyocyte hypertrophy stimulators also triggered the appearance of Golgiphagy in H9c2 cells. Importantly, the co-immunoprecipitation assay indicated endogenous GOLPH3 interacted with LC3B in H9c2 cells, HUVECs, HA-VSMCs. However, knocking down GOLPH3 inhibited the Golgiphagy. SIGNIFICANCE: This study unveiled a new selective autophagy of the Golgi apparatus (Golgiphagy). In addition, GOLPH3 might act as a novel cargo receptor to regulate Golgiphagy. Maintaining homeostasis of the Golgi apparatus via GOLPH3-mediated autophagy was indispensable for cell survival.
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Autofagia/fisiología , Aparato de Golgi/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Animales , Línea Celular , Supervivencia Celular/fisiología , Técnicas de Silenciamiento del Gen , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inmunoprecipitación , Proteínas de la Membrana/genética , Microscopía Electrónica de Transmisión , Miocitos Cardíacos/metabolismo , RatasRESUMEN
Excess iron accumulation and cardiac oxidative stress have been shown as important mediators of cardiac hypertrophy, whereas it remains largely elusive about the occurrence of mitochondrial iron overload and its significance during cardiac hypertrophy. In the present study, we aim to investigate the role of NCOA4-mediated ferritinophagy and SFXN1-dependent mitochondria iron overload in apelin-13-induced cardiomyocytes hypertrophy. Apelin-13 significantly promotes ferric citrate (FAC)-induced total cellular and mitochondria ion production, as well as mitochondria ROS contents. Mechanistically, apelin-13 effectively induces the expression of SFXN1, a mitochondria iron transporting protein and NCOA4, a cargo receptor of ferritinophagy in dose and time-dependent manner. Conversely, blockade of APJ by F13A abolishes these stimulatory effects. In addition, apelin-13-triggered mitochondria iron overload is reversed by the genetic inhibition of SFXN1 and NCOA4. NCOA4 deficiency via its silencing also interferes with the enhanced expression of SFXN1 evoked by apelin-13. In apelin-13-treated H9c2 cells, the promotion in cell diameter, volume as well as protein contents are obviously suppressed by the knockdown of NCOA4 and SFXN1 with their corresponding siRNAs. Remarkably, the human and murine hypertrophic hearts models, as well as apelin-13-injected mice models, present evident cardiac mitochondrial iron deposition and raised expressions of NCOA4 and SFXN1. Taken together, these results provide experimental evidences that NCOA4-mediated ferritinophagy might be defined as an essential mechanism leading to apelin-13-cardiomyocytes hypertrophy in SFXN1-dependent mitochondria iron overload manners.