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1.
Biochem Pharmacol ; 224: 116234, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38670436

RESUMEN

Ionizing radiation, a standard therapeutic approach for lung cancer, often leads to cellular senescence and the induction of epithelial-mesenchymal transition (EMT), posing significant challenges in treatment efficacy and cancer progression. Overcoming these obstacles is crucial for enhancing therapeutic outcomes in lung cancer management. This study investigates the effects of ionizing radiation and gemcitabine on lung cancer cells, with a focus on induced senescence, EMT, and apoptosis. Human-derived A549, PC-9, and mouse-derived Lewis lung carcinoma cells exposed to 10 Gy X-ray irradiation exhibited senescence, as indicated by morphological changes, ß-galactosidase staining, and cell cycle arrest through the p53-p21 pathway. Ionizing radiation also promoted EMT via TGFß/SMAD signaling, evidenced by increased TGFß1 levels, altered EMT marker expressions, and enhanced cell migration. Gemcitabine, a first-line lung cancer treatment, was shown to enhance apoptosis in senescent cells caused by radiation. It inhibited cell proliferation, induced mitochondrial damage, and triggered caspase-mediated apoptosis, thus mitigating EMT in vitro. Furthermore, in vivo studies using a lung cancer mouse model revealed that gemcitabine, combined with radiation, significantly reduced tumor volume and weight, extended survival, and suppressed malignancy indices in irradiated tumors. Collectively, these findings demonstrate that gemcitabine enhances the therapeutic efficacy against radiation-resistant lung cancer cells, both by inducing apoptosis in senescent cells and inhibiting EMT, offering potential improvements in lung cancer treatment strategies.


Asunto(s)
Antimetabolitos Antineoplásicos , Senescencia Celular , Desoxicitidina , Transición Epitelial-Mesenquimal , Gemcitabina , Neoplasias Pulmonares , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Senescencia Celular/efectos de los fármacos , Senescencia Celular/efectos de la radiación , Animales , Humanos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de la radiación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Ratones , Antimetabolitos Antineoplásicos/farmacología , Línea Celular Tumoral , Ratones Endogámicos C57BL , Células A549 , Radiación Ionizante , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación
2.
Artículo en Inglés | MEDLINE | ID: mdl-38607202

RESUMEN

Objective: Study the relationship between ß2 microglobulin, small density, low-density lipoprotein and carotid plaque instability after acute thrombolysis in ischemic stroke patients (IS). Methods: 319 patients with acute cerebral infarction who were treated by thrombolysis in the Department of Neurology, Chongming Branch of Shanghai Xinhua Hospital from January 2017 to May 2022 were included retrospectively. All subjects have undergone a carotid artery ultrasound examination for plaque. According to the ultrasound results, the subjects were divided into plaque-free group (94 cases), a stable plaque group (38 cases) and an unstable plaque group (187 cases). Use an automatic blood biochemical analyzer to detect routine indicators. At the same time, compare the differences of risk factors and biochemical indicators among the groups according to the demographic data of the patient's previous hospitalization. To further evaluate the related risk factors of the instability of carotid plaque in patients through the multivariate logistic regression analysis, the odds ratio (OR) and 95% confidence interval (95% CI) were calculated. Analysis the predictive value of ß2 microglobulin and small density low density lipoprotein on the instability of carotid plaque in I.S. patients after acute thrombolysis through subject work characteristic curve (ROC). Results: Among 319 patients, 187 had unstable plaque accounting for 58.6% and 38 had stable plaque accounting for 11.9%, according to the comparison of general clinical data. Lymphocyte, neutrophil ratio, triglyceride, T3, Hcy, ß2 microglobulin has statistical significance in the presence or absence of plaque. Lymphocytes, small dense low-density lipoprotein, ß2 microglobulin have statistical significance in the stability of plaque (P < .05). Total cholesterol, hypertension, ß2 microglobulin and small density low-density lipoprotein may be independent risk factors of carotid plaque instability through multivariate logistic regression analysis (P < .05). The area under ROC curve showed that ß2 microglobulin AUC: 0.6388, P < .05, small density low-density lipoprotein AUC: 0.6086, P < .05, combined diagnosis AUC: 0.6924, P < .05. Conclusion: ß2 microglobulin and density low-density lipoprotein are independent risk factors of carotid artery plaque instability in I.S. patients after acute thrombolysis. Moreover, the sensibility and differential of combined diagnosis are higher, which has certain predictive value for the instability of carotid plaque in such patients.

3.
Am J Ophthalmol ; 263: 141-151, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38458409

RESUMEN

PURPOSE: This study aims to appraise the therapeutic effectiveness of intravitreal injections anti-vascular endothelial growth factor (anti-VEGF) vs alternative therapies in managing radiation retinopathy (RR). DESIGN: Systematic review and meta-analysis. METHODS: We obtained comprehensive data retrieval using PubMed, Embase, Web of Science, Scopus, and the Cochrane Library from their inception until December 15, 2023. This review included randomized controlled trials (RCTs) and nonrandomized studies (NRSs) reporting on best-corrected visual acuity (BCVA) among RR patients treated with intravitreal anti-VEGF. Study selection and data extraction were meticulously performed by 2 independent reviewers. The Cochrane Risk of Bias Tool 2.0 (RoB 2.0) and Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) scales were utilized for bias risk assessment. Quantification of heterogeneity was executed using Q, H, and I2 statistics. The primary endpoint was the BCVA at the final observation point of each study. Secondary endpoints included central retinal thickness (CRT), foveal avascular zone (FAZ) area, and capillary density (CD) at the level of superficial capillary plexus. Subgroup analyses were undertaken to explore potential heterogeneity sources possibly due to treatment duration and study design. Sensitivity analyses were conducted to ascertain result stability. RESULTS: This analysis incorporated 7 studies (including 3 RCTs) encompassing 922 patients afflicted with RR. Relative to other treatment modalities, intravitreal anti-VEGF therapy was associated with a statistically significant mean decrease in BCVA of -0.34 logMAR (95% CI, -0.39 to -0.30 logMAR; I2 = 87.70%; P < .001), and a substantial reduction in CRT of -34.65 µm (95% CI, -50.70 to -18.60 µm; I2 = 30.40%; P < .001). Additionally, a reduction in the FAZ area by -0.69 mm² (95% CI, -0.91 to -0.46 mm², I2 = 0%; P < .001) was observed. A positive tendency was noted in CD at the superficial capillary plexus between anti-VEGF and other therapeutic interventions. CONCLUSIONS: Intravitreal anti-VEGF injections, in comparison to other treatments, demonstrate superior efficacy in enhancing BCVA and reducing CRT, thereby underscoring the potential of anti-VEGF in ameliorating radiation retinopathy outcomes. However, the conclusions are constrained by the incorporation of data from some NRSs and the small sample sizes.


Asunto(s)
Inhibidores de la Angiogénesis , Inyecciones Intravítreas , Traumatismos por Radiación , Enfermedades de la Retina , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual , Humanos , Inhibidores de la Angiogénesis/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Traumatismos por Radiación/tratamiento farmacológico , Agudeza Visual/fisiología , Enfermedades de la Retina/tratamiento farmacológico , Resultado del Tratamiento , Tomografía de Coherencia Óptica
4.
Artículo en Inglés | MEDLINE | ID: mdl-38261495

RESUMEN

Balance plays a crucial role in human life and social activities. Maintaining balance is a relatively complex process that requires the participation of various balance control subsystems (BCSes). However, previous studies have primarily focused on evaluating an individual's overall balance ability or the ability of each BCS in isolation, without considering how they influence (or interact with) each other. The first study used clinical scales to evaluate the functions of the four BCSes, namely Reactive Postural Control (RPC), Anticipatory Postural Adjustment (APA), Dynamic Gait (DG), and Sensory Orientation (SO), and psychological factors such as fear of falling (FOF). A hierarchical structural equation modeling (SEM) was used to investigate the relationship between the BCSes and their association with FOF. The second study involved using posturography to measure and extract parameters from the center of pressure (COP) signal. SEM with sparsity constraint was used to analyze the relationship between vision, proprioception, and vestibular sense on balance based on the extracted COP parameters. The first study revealed that the RPC, APA, DG and SO indirectly influenced each other through their overall balance ability, and their association with FOF was not the same. APA has the strongest association with FOF, while RPC has the least association with FOF. The second study revealed that sensory inputs, such as vision, proprioception, and vestibular sensing, directly affected each other, but their associations were not identical. Among them, proprioception plays the most important role in the three sensory subsystems. This study provides the first numerical evidence that the BCSes are not independent of each other and exist in direct or indirect interplay. This approach has important implications for the diagnosis and management of balance-related disorders in clinical settings and improving our understanding of the underlying mechanisms of balance control.


Asunto(s)
Miedo , Marcha , Humanos , Análisis de Clases Latentes , Equilibrio Postural
5.
J Mol Biol ; 436(2): 168383, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38070861

RESUMEN

Creatine is an essential metabolite for the storage and rapid supply of energy in muscle and nerve cells. In humans, impaired metabolism, transport, and distribution of creatine throughout tissues can cause varying forms of mental disability, also known as creatine deficiency syndrome (CDS). So far, 80 mutations in the creatine transporter (SLC6A8) have been associated to CDS. To better understand the effect of human genetic variants on the physiology of SLC6A8 and their possible impact on CDS, we studied 30 missense variants including 15 variants of unknown significance, two of which are reported here for the first time. We expressed these variants in HEK293 cells and explored their subcellular localization and transport activity. We also applied computational methods to predict variant effect and estimate site-specific changes in thermodynamic stability. To explore variants that might have a differential effect on the transporter's conformers along the transport cycle, we constructed homology models of the inward facing, and outward facing conformations. In addition, we used mass-spectrometry to study proteins that interact with wild type SLC6A8 and five selected variants in HEK293 cells. In silico models of the protein complexes revealed how two variants impact the interaction interface of SLC6A8 with other proteins and how pathogenic variants lead to an enrichment of ER protein partners. Overall, our integrated analysis disambiguates the pathogenicity of 15 variants of unknown significance revealing diverse mechanisms of pathogenicity, including two previously unreported variants obtained from patients suffering from the creatine deficiency syndrome.


Asunto(s)
Encefalopatías Metabólicas Innatas , Creatina , Discapacidad Intelectual Ligada al Cromosoma X , Proteínas del Tejido Nervioso , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática , Humanos , Creatina/deficiencia , Células HEK293 , Discapacidad Intelectual Ligada al Cromosoma X/genética , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/genética , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/deficiencia , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/genética , Encefalopatías Metabólicas Innatas/genética , Análisis Mutacional de ADN/métodos , Mutación Missense , Biología Computacional/métodos
6.
IEEE J Biomed Health Inform ; 28(2): 690-701, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37053059

RESUMEN

OBJECTIVE: Cognition is an essential human function, and its development in infancy is crucial. Traditionally, pediatricians used clinical observation or medical imaging to assess infants' current cognitive development (CD) status. The object of pediatricians' greater concern is however their future outcomes, because high-risk infants can be identified early in life for intervention. However, this opportunity has not yet been realized. Fortunately, some recent studies have shown that the general movement (GM) performance of infants around 3-4 months after birth might reflect their future CD status, which gives us an opportunity to achieve this goal by cameras and artificial intelligence. METHODS: First, infants' GM videos were recorded by cameras, from which a series of features reflecting their bilateral movement symmetry (BMS) were extracted. Then, after at least eight months of natural growth, the infants' CD status was evaluated by the Bayley Infant Development Scale, and they were divided into high-risk and low-risk groups. Finally, the BMS features extracted from the early recorded GM videos were fed into the classifiers, using late infant CD risk assessment as the prediction target. RESULTS: The area under the curve, recall and precision values reached 0.830, 0.832, and 0.823 for two-group classification, respectively. CONCLUSION: This pilot study demonstrates that it is possible to automatically predict the CD of infants around the age of one year based on their GMs recorded early in life. SIGNIFICANCE: This study not only helps clinicians better understand infant CD mechanisms, but also provides an economical, portable and non-invasive way to screen infants at high-risk early to facilitate their recovery.


Asunto(s)
Inteligencia Artificial , Desarrollo Infantil , Lactante , Niño , Humanos , Proyectos Piloto , Cognición , Movimiento
7.
Cell Death Differ ; 30(11): 2432-2445, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37828085

RESUMEN

Ferroptosis is a type of cell death characterized by the accumulation of intracellular iron and an increase in hazardous lipid peroxides. Ferroptosis and autophagy are closely related. Ionizing radiation is a frequently used cancer therapy to kill malignancies. We found that ionizing radiation induces both ferroptosis and autophagy and that there is a form of mutualism between the two processes. Ionizing radiation also causes lipid droplets to form in proximity to damaged mitochondria, which, through the action of mitophagy, results in the degradation of the peridroplet mitochondria by lysosomes and the consequent release of free fatty acids and a significant increase in lipid peroxidation, thus promoting ferroptosis. Ionizing radiation has a stronger, fatal effect on cells with a high level of mitophagy, and this observation suggests a novel strategy for tumor treatment.


Asunto(s)
Ferroptosis , Neoplasias , Humanos , Ácidos Grasos no Esterificados/farmacología , Mitofagia , Hierro/metabolismo , Neoplasias/metabolismo , Peroxidación de Lípido , Radiación Ionizante , Especies Reactivas de Oxígeno/metabolismo
8.
Cell Death Discov ; 9(1): 267, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507394

RESUMEN

Radiotherapy is an important cancer treatment strategy that causes DNA damage in tumor cells either directly or indirectly. Autophagy is a physiological process linked to DNA damage. Mitophagy is a form of autophagy, which specifically targets and eliminates impaired mitochondria, thereby upholding cellular homeostasis. However, the connection between DNA damage and mitophagy has yet to be fully elucidated. We found that mitophagy, as an upstream signal, increases ionizing radiation-induced DNA damage by downregulating or overexpressing key mitophagy proteins Parkin and BNIP3. Enhancing the basal level of mitophagy in conjunction with X-ray irradiation can potentially diminish cell cycle arrest at the G2/M phase, substantially elevate the accumulation of γ-H2AX, 53BP1, and PARP1 foci within the nucleus, augment DNA damage, and facilitate the demise of tumor cells. Consequently, this approach prolongs the survival of melanoma-bearing mice. The findings of this study are anticipated to offer a therapeutic approach for enhancing the therapeutic effectiveness of radiotherapy.

9.
J Cell Sci ; 136(6)2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36807531

RESUMEN

The coronavirus SARS-CoV-2, the agent of the deadly COVID-19 pandemic, is an enveloped virus propagating within the endocytic and secretory organelles of host mammalian cells. Enveloped viruses modify the ionic homeostasis of organelles to render their intra-luminal milieu permissive for viral entry, replication and egress. Here, we show that infection of Vero E6 cells with the delta variant of the SARS-CoV-2 alkalinizes the endoplasmic reticulum (ER)-Golgi intermediate compartment (ERGIC) as well as lysosomes, mimicking the effect of inhibitors of vacuolar proton ATPases. We further show the envelope protein of SARS-CoV-2 accumulates in the ERGIC when expressed in mammalian cells and selectively dissipates the ERGIC pH. This viroporin action is prevented by mutations of Val25 but not Asn15 within the channel pore of the envelope (E) protein. We conclude that the envelope protein acts as a proton channel in the ERGIC to mitigate the acidity of this intermediate compartment. The altered pH homeostasis of the ERGIC likely contributes to the virus fitness and pathogenicity, making the E channel an attractive drug target for the treatment of COVID-19.


Asunto(s)
COVID-19 , Proteínas del Envoltorio Viral , Animales , Humanos , Proteínas del Envoltorio Viral/metabolismo , Proteínas Viroporinas/metabolismo , COVID-19/metabolismo , Protones , Pandemias , SARS-CoV-2/metabolismo , Aparato de Golgi/metabolismo , Lisosomas/metabolismo , Mamíferos/metabolismo
10.
EMBO Rep ; 23(12): e54978, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36321428

RESUMEN

Mitochondrial Ca2+ ions are crucial regulators of bioenergetics and cell death pathways. Mitochondrial Ca2+ content and cytosolic Ca2+ homeostasis strictly depend on Ca2+ transporters. In recent decades, the major players responsible for mitochondrial Ca2+ uptake and release have been identified, except the mitochondrial Ca2+ /H+ exchanger (CHE). Originally identified as the mitochondrial K+ /H+ exchanger, LETM1 was also considered as a candidate for the mitochondrial CHE. Defining the mitochondrial interactome of LETM1, we identify TMBIM5/MICS1, the only mitochondrial member of the TMBIM family, and validate the physical interaction of TMBIM5 and LETM1. Cell-based and cell-free biochemical assays demonstrate the absence or greatly reduced Na+ -independent mitochondrial Ca2+ release in TMBIM5 knockout or pH-sensing site mutants, respectively, and pH-dependent Ca2+ transport by recombinant TMBIM5. Taken together, we demonstrate that TMBIM5, but not LETM1, is the long-sought mitochondrial CHE, involved in setting and regulating the mitochondrial proton gradient. This finding provides the final piece of the puzzle of mitochondrial Ca2+ transporters and opens the door to exploring its importance in health and disease, and to developing drugs modulating Ca2+ exchange.


Asunto(s)
Antiportadores , Protones , Antiportadores/genética
12.
Neuro Endocrinol Lett ; 43(2): 68-76, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35786817

RESUMEN

OBJECTIVES: The etiology and pathologic mechanism underlying Alzheimer's disease (AD) are not clear. This study determined the effects of tau on amyloid-beta peptide(Aß)-induced synaptic damages in a Drosophila model of AD. METHODS: Galactose-regulated upstream promoter element 4(Gal4) and an upstream active sequence system was used to establish four kinds of Aß transgenic Drosophila models of AD. Behavioral evaluation and immunohistochemical localization were performed in Aß transgenic Drosophila models. Tau mutants were introduced into arctic mutant Aß1-42 (arctic mutant Aß [Aßarc]) Drosophila. The P{Gal4}A307 Drosophila strain was used as a control group; 12 strains were obtained to determine the effects of tau with or without Aßarc. Electrophysiologic records of the tau mutant groups were created. RESULTS: The flight and crawling ability of Aß transgenic Drosophila were gradually weakened compared to the control group, and the life span was significantly shorter than the control group. Aß was specifically expressed in the Drosophila giant fiber pathway and further accumulated in neuronal cell bodies based on immunohistochemistry. The percentage of the excitatory junctional potential (EJP) response in transgenic Drosophila expressing Aßarc was significantly decreased, which was approximately 40% lower than the control group. The tau deletion mutation alleviated the synaptic transmission disorder caused by Aß and improved the viability of Drosophila. CONCLUSION: The tau deletion mutation significantly improved the synaptic damage caused by Aß, and tau protein played an indispensable role in the synaptic dysfunction caused by Aß, suggesting that Aß and tau have close interactions in the pathogenesis of AD.


Asunto(s)
Enfermedad de Alzheimer , Proteínas tau , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Drosophila/genética , Drosophila/metabolismo , Galactosa , Ratones , Ratones Transgénicos , Fosforilación , Proteínas tau/genética , Proteínas tau/metabolismo
13.
Cells ; 11(11)2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35681417

RESUMEN

Calreticulin is an endoplasmic Ca2+ binding protein and molecular chaperone. As a cardiac embryonic gene, calreticulin is essential for heart development. The protein supports Ca2+-dependent signaling events that are critical to cardiomyocyte differentiation and cardiogenesis. The increased expression of calreticulin and endoplasmic reticulum/sarcoplasmic reticulum Ca2+ capacity produces cardiomyocytes with enhanced efficiency, and detrimental mechanical stretching of cardiac fibroblasts, leading to cardiac pathology. Deletion of the calreticulin gene in adult cardiomyocytes results in left ventricle dilation, an impaired electrocardiogram, and heart failure. These observations indicate that a well-adjusted endoplasmic reticulum and calreticulin-dependent Ca2+ pool in cardiomyocytes are critical for the maintenance of proper cardiac function.


Asunto(s)
Calcio , Calreticulina , Calcio/metabolismo , Calreticulina/genética , Calreticulina/metabolismo , Retículo Endoplásmico/metabolismo , Miocitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo
14.
Neoplasma ; 69(4): 965-975, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35723196

RESUMEN

NPM1 plays an important role in the occurrence and development of leukemia and various solid tumors. This study aimed to investigate the expression of NPM1 in gastric cancer (GC) and adjacent normal tissues, study the relationship between NPM1 expression and clinicopathological characteristics in GC patients, and explore the impact of NPM1 expression on the diagnosis and prognosis of GC. We used tissue microarray immunohistochemical analysis to examine the expression level of NPM1 in GC and adjacent tissues and analyzed the relationship between NPM1 expression, clinicopathological factors, and GC prognosis. Prognostic values of NPM1 mRNA were also investigated using an online database. qRT-PCR was used to detect the expression of NPM1 mRNA in cancer and adjacent tissues. According to microarray immunohistochemical analysis and qRT-PCR results, NPM1 had a high expression in all adjacent normal tissues. Microarray immunohistochemical analyses demonstrated that the NPM1 was lowly expressed in 75.5% of GC tissues but highly expressed in 24.5% of GC tissues. qRT-PCR results showed NPM1 mRNA low expression in most GC tissues. NPM1 high expression group was associated with a better overall survival rate and disease-free survival rate than the NPM1 low expression group (p<0.01). This result is consistent with that of the online database. The receiver operating characteristics curve showed that NPM1 was valuable in the diagnosis of GC. The assessment of NPM1 expression in GC samples may represent a useful tool for GC diagnosis and prognosis assessment.


Asunto(s)
Neoplasias Gástricas , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Nucleofosmina , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
15.
J Biol Chem ; 298(3): 101607, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35065962

RESUMEN

The stromal interaction molecule 1 (STIM1) is an endoplasmic reticulum (ER) Ca2+ sensor that regulates the activity of Orai plasma membrane Ca2+ channels to mediate the store-operated Ca2+ entry pathway essential for immunity. Uncoordinated 93 homolog B1 (UNC93B1) is a multiple membrane-spanning ER protein that acts as a trafficking chaperone by guiding nucleic-acid sensing toll-like receptors to their respective endosomal signaling compartments. We previously showed that UNC93B1 interacts with STIM1 to promote antigen cross-presentation in dendritic cells, but the STIM1 binding site(s) and activation step(s) impacted by this interaction remained unknown. In this study, we show that UNC93B1 interacts with STIM1 in the ER lumen by binding to residues in close proximity to the transmembrane domain. Cysteine crosslinking in vivo showed that UNC93B1 binding promotes the zipping of transmembrane and proximal cytosolic helices within resting STIM1 dimers, priming STIM1 for translocation. In addition, we show that UNC93B1 deficiency reduces store-operated Ca2+ entry and STIM1-Orai1 interactions and targets STIM1 to lighter ER domains, whereas UNC93B1 expression accelerates the recruitment of STIM1 to cortical ER domains. We conclude that UNC93B1 therefore acts as a trafficking chaperone by maintaining the pool of resting STIM1 proteins in a state primed for activation, enabling their rapid translocation in an extended conformation to cortical ER signaling compartments.


Asunto(s)
Calcio , Retículo Endoplásmico , Proteínas de Transporte de Membrana , Molécula de Interacción Estromal 1 , Animales , Calcio/metabolismo , Señalización del Calcio/fisiología , Membrana Celular/metabolismo , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Mamíferos/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Molécula de Interacción Estromal 1/genética , Molécula de Interacción Estromal 1/metabolismo
16.
IEEE J Biomed Health Inform ; 26(5): 2124-2135, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34818197

RESUMEN

OBJECTIVE: Based on cybernetics, a large system can be divided into subsystems, and the stability of each can determine the overall properties of the system. However, this stability analysis perspective has not yet been employed in electrocardiogram (ECG) signals. This is the first study to attempt to evaluate whether the stability of decomposed ECG subsystems can be analyzed in order to effectively investigate the overall performance of ECG signals, and aid in disease diagnosis. METHODS: We used seven different cardiac pathologies (myocardial infarction, cardiomyopathy, bundle branch block, dysrhythmia, hypertrophy, myocarditis, and valvular heart disease) to illustrate our method. Dynamic mode decomposition (DMD) was first used to decompose ECG signals into dynamic modes (DMs) which can be regarded as ECG subsystems. Then, the features related to the DMs stabilities were extracted, and nine common classifiers were implemented for classification of these pathologies. RESULTS: Most features were significant for differentiating the above-mentioned groups (p value<0.05 after Bonferroni correction). In addition, our method outperformed all existing methods for cardiac pathology classification. CONCLUSION: We have provided a new spatial and temporal decomposition method, namely DMD, to study ECG signals. SIGNIFICANCE: Our method can reveal new cardiac mechanisms, which can contribute to the comprehensive understanding of its underlying mechanisms and disease diagnosis, and thus, can be widely used for ECG signal analysis in the future.


Asunto(s)
Electrocardiografía , Infarto del Miocardio , Algoritmos , Arritmias Cardíacas/diagnóstico , Electrocardiografía/métodos , Corazón , Humanos , Infarto del Miocardio/diagnóstico , Procesamiento de Señales Asistido por Computador
17.
Biochem Biophys Res Commun ; 589: 71-77, 2022 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-34894559

RESUMEN

Hyccin/FAM126A mutations are linked to hypomyelination and congenital cataract disease (HCC), but whether and how Hyccin/FAM126A deficiency causes hypomyelination remains undetermined. This study shows Hyccin/FAM126A expression was necessary for the expression of other components of the PI4KIIIα complex in Drosophila. Knockdown of Hyccin/FAM126A in glia reduced the enrichment of glial cells, disrupted axonal sheaths and visual ability in the visual system, and these defects could be fully rescued by overexpressing either human FAM126A or FAM126B, and partially rescued by overexpressing a plasma membrane-targeting recombinant mouse PI4KIIIα. Additionally, PI4KIIIα knockdown in glia phenocopied Hyccin/FAM126A knockdown, and this was partially rescued by overexpressing the recombinant PI4KIIIα, but not human FAM126A or FAM126B. This study establishes an animal model of HCC and indicates that Hyccin/FAM126A plays an essential role in glial enrichment and axonal sheath in a cell-autonomous manner in the visual system via controlling the expression and stabilization of the PI4KIIIα complex at the plasma membrane.


Asunto(s)
Axones , Membrana Celular , Proteínas de Drosophila , Drosophila melanogaster , Antígenos de Histocompatibilidad Menor , Neuroglía , Fosfotransferasas (Aceptor de Grupo Alcohol) , Animales , Axones/metabolismo , Membrana Celular/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Técnicas de Silenciamiento del Gen , Proteínas Fluorescentes Verdes/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Complejos Multiproteicos/metabolismo , Neuroglía/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Unión Proteica , Vías Visuales/metabolismo
18.
Elife ; 102021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34913437

RESUMEN

Efficient immune responses require Ca2+ fluxes across ORAI1 channels during engagement of T cell receptors (TCR) at the immune synapse (IS) between T cells and antigen presenting cells. Here, we show that ZDHHC20-mediated S-acylation of the ORAI1 channel at residue Cys143 promotes TCR recruitment and signaling at the IS. Cys143 mutations reduced ORAI1 currents and store-operated Ca2+ entry in HEK-293 cells and nearly abrogated long-lasting Ca2+ elevations, NFATC1 translocation, and IL-2 secretion evoked by TCR engagement in Jurkat T cells. The acylation-deficient channel remained in cholesterol-poor domains upon enforced ZDHHC20 expression and was recruited less efficiently to the IS along with actin and TCR. Our results establish S-acylation as a critical regulator of ORAI1 channel trafficking and function at the IS and reveal that ORAI1 S-acylation enhances TCR recruitment to the synapse.


Asunto(s)
Aciltransferasas/genética , Calcio/metabolismo , Proteína ORAI1/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Acilación , Aciltransferasas/metabolismo , Células Presentadoras de Antígenos/metabolismo , Células HEK293 , Humanos , Células Jurkat/metabolismo , Microdominios de Membrana/metabolismo , Proteína ORAI1/metabolismo , Azufre/metabolismo , Linfocitos T/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-34029190

RESUMEN

Recent studies have investigated bilateral gaits based on the causality analysis of kinetic (or kinematic) signals recorded using both feet. However, these approaches have not considered the influence of their simultaneous causation, which might lead to inaccurate causality inference. Furthermore, the causal interaction of these signals has not been investigated within their frequency domain. Therefore, in this study we attempted to employ a causal-decomposition approach to analyze bilateral gait. The vertical ground reaction force (VGRF) signals of Parkinson's disease (PD) patients and healthy control (HC) individuals were taken as an example to illustrate this method. To achieve this, we used ensemble empirical mode decomposition to decompose the left and right VGRF signals into intrinsic mode functions (IMFs) from the high to low frequency bands. The causal interaction strength (CIS) between each pair of IMFs was then assessed through the use of their instantaneous phase dependency. The results show that the CISes between pairwise IMFs decomposed in the high frequency band of VGRF signals can not only markedly distinguish PD patients from HC individuals, but also found a significant correlation with disease progression, while other pairwise IMFs were not able to produce this. In sum, we found for the first time that the frequency specific causality of bilateral gait may reflect the health status and disease progression of individuals. This finding may help to understand the underlying mechanisms of walking and walking-related diseases, and offer broad applications in the fields of medicine and engineering.


Asunto(s)
Análisis de la Marcha , Marcha , Fenómenos Biomecánicos , Causalidad , Humanos , Caminata
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