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1.
Exp Cell Res ; 437(1): 113994, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479704

RESUMO

m6A modification has been studied in tumors, but its role in host anti-tumor immune response and TAMs polarization remains unclear. The fatty acid oxidation (FAO) process of TAMs is also attracting attention. A co-culture model of colorectal cancer (CRC) cells and macrophages was used to simulate the tumor microenvironment. Expression changes of m6A demethylase genes FTO and ALKBH5 were screened. ALKBH5 was further investigated. Gain-of-function experiments were conducted to study ALKBH5's effects on macrophage M2 polarization, CRC cell viability, proliferation, migration, and more. Me-RIP and Actinomycin D assays were performed to study ALKBH5's influence on CPT1A, the FAO rate-limiting enzyme. AMP, ADP, and ATP content detection, OCR measurement, and ECAR measurement were used to explore ALKBH5's impact on macrophage FAO level. Rescue experiments validated ALKBH5's mechanistic role in macrophage M2 polarization and CRC malignant development. In co-culture, CRC cells enhance macrophage FAO and suppress m6A modification in M2 macrophages. ALKBH5 was selected as the gene for further investigation. ALKBH5 mediates CPT1A upregulation by removing m6A modification, promoting M2 macrophage polarization and facilitating CRC development. These findings indicate that ALKBH5 enhances fatty acid metabolism and M2 polarization of macrophages by upregulating CPT1A, thereby promoting CRC development.


Assuntos
Neoplasias Colorretais , Macrófagos , Humanos , Regulação para Cima/genética , Macrófagos/metabolismo , Neoplasias Colorretais/patologia , Ácidos Graxos/metabolismo , Microambiente Tumoral , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
2.
Neurobiol Dis ; 198: 106549, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38830476

RESUMO

BACKGROUND: Multiple system atrophy (MSA) and Parkinson's disease (PD) are neurodegenerative disorders characterized by α-synuclein pathology, disrupted iron homeostasis and impaired neurochemical transmission. Considering the critical role of iron in neurotransmitter synthesis and transport, our study aims to identify distinct patterns of whole-brain iron accumulation in MSA and PD, and to elucidate the corresponding neurochemical substrates. METHODS: A total of 122 PD patients, 58 MSA patients and 78 age-, sex-matched health controls underwent multi-echo gradient echo sequences and neurological evaluations. We conducted voxel-wise and regional analyses using quantitative susceptibility mapping to explore MSA or PD-specific alterations in cortical and subcortical iron concentrations. Spatial correlation approaches were employed to examine the topographical alignment of cortical iron accumulation patterns with normative atlases of neurotransmitter receptor and transporter densities. Furthermore, we assessed the associations between the colocalization strength of neurochemical systems and disease severity. RESULTS: MSA patients exhibited increased susceptibility in the striatal, midbrain, cerebellar nuclei, as well as the frontal, temporal, occipital lobes, and anterior cingulate gyrus. In contrast, PD patients displayed elevated iron levels in the left inferior occipital gyrus, precentral gyrus, and substantia nigra. The excessive iron accumulation in MSA or PD correlated with the spatial distribution of cholinergic, noradrenaline, glutamate, serotonin, cannabinoids, and opioid neurotransmitters, and the degree of this alignment was related to motor deficits. CONCLUSIONS: Our findings provide evidence of the interaction between iron accumulation and non-dopamine neurotransmitters in the pathogenesis of MSA and PD, which inspires research on potential targets for pharmacotherapy.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Humanos , Atrofia de Múltiplos Sistemas/metabolismo , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ferro/metabolismo , Neurotransmissores/metabolismo , Mapeamento Encefálico/métodos
3.
Biochem Biophys Res Commun ; 731: 150360, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39018970

RESUMO

Exercise is known to be an effective intervention for depression. NADPH has been demonstrated to have neuroprotective effects in our previous studies. This study aimed to investigate if NADPH has antidepressant effects and can mimic the effects of exercise in a chronic unpredictable stress (CUS) rat model. CUS rats underwent an 8-week swimming exercise (30 min/d, 5d/w) or were intraperitoneally administered 4 mg/kg or 8 mg/kg NADPH. The open field test (OFT), sucrose preference test (SPT), novelty-suppressed feeding test (NSFT), and forced swimming test (FST) were used to examine the antidepressant-like behaviors of the rats. Exercise, 4 mg/kg, and 8 mg/kg NADPH similarly reduced anxiety, as demonstrated by the number of fecal pellets. Meanwhile, exercise and 8 mg/kg NADPH significantly increased locomotion activity in the OFT. Exercise, 4 mg/kg, and 8 mg/kg NADPH effectively reversed CUS-induced anhedonia in rats in the SPT. Exercise, 4 mg/kg, and 8 mg/kg NADPH had no impact on appetite of depressed rats; however, 8 mg/kg NADPH increased the rats' exploratory activity in the NSFT. Exercise, 4 mg/kg, and 8 mg/kg NADPH significantly reduced the immobility time of CUS model rats, while exercise and 8 mg/kg NADPH postponed the early CUS-induced "immobility" in the FST. These results demonstrated that NADPH has similar antidepressant-like effects to exercise in CUS-induced depression model rats and is a potential exercise-mimicking antidepressant.

4.
J Neurosci Res ; 102(5): e25357, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38803227

RESUMO

Aging is widely acknowledged as the primary risk factor for brain degeneration, with Parkinson's disease (PD) tending to follow accelerated aging trajectories. We aim to investigate the impact of structural brain aging on the temporal dynamics of a large-scale functional network in PD. We enrolled 62 PD patients and 32 healthy controls (HCs). The level of brain aging was determined by calculating global and local brain age gap estimates (G-brainAGE and L-brainAGE) from structural images. The neural network activity of the whole brain was captured by identifying coactivation patterns (CAPs) from resting-state functional images. Intergroup differences were assessed using the general linear model. Subsequently, a spatial correlation analysis between the L-brainAGE difference map and CAPs was conducted to uncover the anatomical underpinnings of functional alterations. Compared to HCs (-3.73 years), G-brainAGE was significantly higher in PD patients (+1.93 years), who also exhibited widespread elevation in L-brainAGE. G-brainAGE was correlated with disease severity and duration. PD patients spent less time in CAPs involving activated default mode and the fronto-parietal network (DMN-FPN), as well as the sensorimotor and salience network (SMN-SN), and had a reduced transition frequency from other CAPs to the DMN-FPN and SMN-SN CAPs. Furthermore, the pattern of localized brain age acceleration showed spatial similarities with the SMN-SN CAP. Accelerated structural brain aging in PD adversely affects brain function, manifesting as dysregulated brain network dynamics. These findings provide insights into the neuropathological mechanisms underlying neurodegenerative diseases and imply the possibility of interventions for modifying PD progression by slowing the brain aging process.


Assuntos
Envelhecimento , Encéfalo , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Envelhecimento/fisiologia , Envelhecimento/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Idoso , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia
5.
J Magn Reson Imaging ; 59(5): 1769-1776, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37501392

RESUMO

BACKGROUND: The status of the hypothalamic-pituitary-gonadal (HPG) axis is important for assessing the onset of physiological or pathological puberty. The reference standard gonadotropin-releasing hormone (GnRH) stimulation test requires hospital admission and repeated blood samples. A simple noninvasive method would be beneficial. OBJECTIVES: To explore a noninvasive method for evaluating HPG axis activation in children using an MRI radiomics model. STUDY TYPE: Retrospective. POPULATION: Two hundred thirty-nine children (83 male; 3.6-14.6 years) with hypophysial MRI and GnRH stimulation tests, randomly divided a training set (168 children) and a test set (71 children). FIELD STRENGTH/SEQUENCE: 3.0 T, 3D isotropic fast spin echo (CUBE) T1-weighted imaging (T1WI) sequences. ASSESSMENT: Radiomics features were extracted from sagittal 3D CUBE T1WI, and imaging signatures were generated using the least absolute shrinkage and selection operator (LASSO) with 10-fold cross-validation. Diagnostic performance for differential diagnosis of HPG status was compared between a radiomics model and MRI features (adenohypophyseal height [aPH] and volume [aPV]). STATISTICAL TESTS: Receiver operating characteristic (ROC) and decision curve analysis (DCA). A P value <0.05 was considered statistically significant. RESULTS: Eight hundred fifty-one radiomics features were extracted and reduced to 10 by the LASSO method in the training cohort. The radiomics model based on CUBE T1WI showed good performance in assessment of HPG axis activation with an area under the ROC curve (AUC) of 0.81 (95% CI: 0.71, 0.91) in the test set. The AUC of the radiomics model was significantly higher than that of aPH (0.81 vs. 0.65) but there was no significant difference compared to aPV (0.81 vs. 0.78, P = 0.58). In DCA analysis, the radiomics signature showed higher net benefit over the aPV and aPH models. DATA CONCLUSIONS: The MRI radiomics model has potential to assess HPG axis activation status noninvasively, potentially providing valuable information in the diagnosis of patients with pathological puberty onset. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Eixo Hipotalâmico-Hipofisário-Gonadal , Adeno-Hipófise , Criança , Humanos , Masculino , Estudos Retrospectivos , Radiômica , Imageamento por Ressonância Magnética/métodos , Adeno-Hipófise/diagnóstico por imagem , Hormônio Liberador de Gonadotropina
6.
Anal Chem ; 95(41): 15350-15356, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37784219

RESUMO

Lipid droplets (LDs) are crucial organelles used to store lipids and participate in lipid metabolism in cells. The abnormal aggregation and polarity change of LDs are associated with the occurrence of diseases, such as steatosis. Herein, the polarity-sensitive probe TBPCPP with a donor-acceptor-π-acceptor (D-A-π-A) structure was designed and synthesized. The TBPCPP has a large Stokes shift (∼220 nm), excellent photostability, high LD targeting, and considerable two-photon absorption (TPA) cross-section (∼226 GM), enabling deep two-photon imaging (∼360 µm). In addition, the fluorescence lifetime of TBPCPP decreases linearly with increasing solvent polarity. Therefore, with the assistance of two-photon fluorescence lifetime imaging microscopy (TP-FLIM), TBPCPP has successfully achieved not only the visualization of polarity changes caused by LD accumulation in HepG-2 cells but also lipid-specific imaging and visualization of different polarities in lipid-rich regions in zebrafish for the first time. Furthermore, TP-FLIM revealed that the polarity gradually decreases during steatosis in HepG-2 cells, which provided new insights into the diagnosis of steatosis.


Assuntos
Gotículas Lipídicas , Peixe-Zebra , Animais , Gotículas Lipídicas/química , Microscopia de Fluorescência/métodos , Fótons , Lipídeos/análise , Corantes Fluorescentes/química
7.
Hum Brain Mapp ; 44(9): 3730-3743, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37042391

RESUMO

Anxiety is characterized by altered brain networks. Directional information flows among dynamic brain networks concerning neuropathogenesis of anxiety have not yet been investigated. The role of directional influences between networks in gene-environment effects on anxiety remains to be further elucidated. In a large community sample, this resting-state functional MRI study estimated dynamic effective connectivity among large-scale brain networks based on a sliding-window approach and Granger causality analysis, providing dynamic and directional information for signal transmission in networks. We first explored altered effective connectivity among networks related to anxiety in distinct connectivity states. Due to the potential gene-environment effects on brain and anxiety, we further performed mediation and moderated mediation analyses to investigate the role of altered effective connectivity networks in relationships between polygenic risk scores, childhood trauma, and anxiety. State and trait anxiety scores showed correlations with altered effective connectivity among extensive networks in distinct connectivity states (p < .05, uncorrected). Only in a more frequent and strongly connected state, there were significant correlations between altered effective connectivity networks and trait anxiety (PFDR <0.05). Furthermore, mediation and moderated mediation analyses showed that the effective connectivity networks played a mediating role in the effects of childhood trauma and polygenic risk on trait anxiety. State-dependent effective connectivity changes among brain networks were significantly related to trait anxiety, and mediated gene-environment effects on trait anxiety. Our work sheds novel light on the neurobiological mechanisms underlying anxiety, and provides new insights into early objective diagnosis and intervention evaluation.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos , Encéfalo , Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade
8.
Hepatology ; 75(1): 140-153, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510514

RESUMO

BACKGROUND AND AIMS: Globally, NAFLD is one of the most common liver disorders, with an estimated prevalence rate of more than 30% in men and 15% in women and an even higher prevalence in people with type 2 diabetes mellitus. Optimal pharmacologic therapeutic approaches for NAFLD are an urgent necessity. APPROACH AND RESULTS: In this study, we showed that compared with healthy controls, hepatic ACSL4 levels in patients with NAFLD were found to be elevated. Suppression of ACSL4 expression promoted mitochondrial respiration, thereby enhancing the capacity of hepatocytes to mediate ß-oxidation of fatty acids and to minimize lipid accumulation by up-regulating peroxisome proliferator-activated receptor coactivator-1 alpha. Moreover, we found that abemaciclib is a potent and selective ACSL4 inhibitor, and low dose of abemaciclib significantly ameliorated most of the NAFLD symptoms in multiple NAFLD mice models. CONCLUSIONS: Therefore, inhibition of ACSL4 is a potential alternative therapeutic approach for NAFLD.


Assuntos
Aminopiridinas/uso terapêutico , Benzimidazóis/uso terapêutico , Coenzima A Ligases/antagonistas & inibidores , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Aminopiridinas/farmacologia , Animais , Benzimidazóis/farmacologia , Biópsia , Coenzima A Ligases/análise , Coenzima A Ligases/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Oxirredução/efeitos dos fármacos
9.
Neurochem Res ; 48(6): 1822-1834, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36723726

RESUMO

Lignans are the main components of Syringa pinnatifolia Hemsl. (SP). Previous studies have shown that SP lignans (SPL) can considerably improve CCl4-induced acute liver injury in mice by the anti-oxidative stress (OS) mechanism. In this study, we investigated the antioxidant effects of SPL on cerebral ischemia/reperfusion injury (CIRI) and its underlying molecular mechanism. We developed a middle cerebral artery occlusion/reperfusion (MCAO/R) model in mice to achieve CIRI and orally administered SPL daily for 1-3 days. We evaluated neurological function deficits and performed hematoxylin and eosin staining. We further calculated the infarct volume. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the brain were detected using corresponding kits. The transcription and protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and NAD(P)H quinone dehydrogenase 1 (NQO1) in brain tissues were analyzed by real-time reverse transcription polymerase chain reaction and western blotting, respectively. The results showed that SPL could remarkably ameliorate neurological functions and pathological damage in brain tissues, reducing the cerebral infarct volume. It also increased the SOD and GPx activities decreased the MDA levels as well as inhibited the expression of (NOX)2 and NOX4. We also found that the mRNA and protein levels of Nrf2, HO-1, and NQO1 in the CIRI mice increased transiently and peaked at 24 h of reperfusion, and then began to decline. SPL could reverse decreasing Nrf2 and HO-1 levels after 24 h. In conclusion, SPL can alleviate CIRI and OS by activating the Nrf2/HO-1 pathway.


Assuntos
Isquemia Encefálica , Lignanas , Traumatismo por Reperfusão , Syringa , Ratos , Camundongos , Animais , Ratos Sprague-Dawley , Syringa/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Antioxidantes/farmacologia , Heme Oxigenase-1/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Traumatismo por Reperfusão/metabolismo , Lignanas/farmacologia , Superóxido Dismutase/metabolismo
10.
Eur Radiol ; 33(12): 8844-8853, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37480547

RESUMO

OBJECTIVES: This study aims at a fully automatic pipeline for measuring the magnetic resonance parkinsonism index (MRPI) using deep learning methods. METHODS: MRPI is defined as the product of the pons area to the midbrain area ratio and the middle cerebellar peduncle (MCP) width to the superior cerebellar peduncle (SCP) width ratio. In our proposed pipeline, we first used nnUNet to segment the brainstem and then employed HRNet to identify two key boundary points so as to sub-divide the whole brainstem into midbrain and pons. HRNet was also employed to predict the MCP endpoints for measuring the MCP width. Finally, we segmented the SCP on an oblique coronal plane and calculated its width. A total of 400 T1-weighted magnetic resonance images (MRIs) were used to train the nnUNet and HRNet models. Five-fold cross-validation was conducted to evaluate our proposed pipeline's performance on the training dataset. We also evaluated the performance of our proposed pipeline on three external datasets. Two of them had two raters manually measuring the MRPI values, providing insights into automatic accuracy versus inter-rater variability. RESULTS: We obtained average absolute percentage errors (APEs) of 17.21%, 18.17%, 20.83%, and 22.83% on the training dataset and the three external validation datasets, while the inter-rater average APE measured on the first two external validation datasets was 11.31%. Our proposed pipeline significantly improved the MRPI quantification accuracy over a representative state-of-the-art traditional approach (p < 0.001). CONCLUSION: The proposed automatic pipeline can accurately predict MRPI that is comparable with manual measurement. CLINICAL RELEVANCE STATEMENT: This study presents an automated magnetic resonance parkinsonism index measurement tool that can analyze large amounts of magnetic resonance images, enhance the efficiency of Parkinsonism-Plus syndrome diagnosis, reduce the workload of clinicians, and minimize the impact of human factors on diagnosis. KEY POINTS: • We propose an automatic pipeline for measuring the magnetic resonance parkinsonism index from magnetic resonance images. • The effectiveness of the proposed pipeline is successfully established on multiple datasets and comparisons with inter-rater measurements. • The proposed pipeline significantly outperforms a state-of-the-art quantification approach, being much closer to ground truth.


Assuntos
Aprendizado Profundo , Doença de Parkinson , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Humanos , Doença de Parkinson/diagnóstico , Paralisia Supranuclear Progressiva/diagnóstico , Transtornos Parkinsonianos/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética
11.
BMC Infect Dis ; 23(1): 707, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864131

RESUMO

BACKGROUND: This study's objective was to investigate the predictors for severe anemia, severe leukopenia, and severe thrombocytopenia when amphotericin B deoxycholate-based induction therapy is used in HIV-infected patients with talaromycosis. METHODS: A total of 170 HIV-infected patients with talaromycosis were enrolled from January 1st, 2019, to September 30th, 2020. RESULTS: Approximately 42.9%, 20.6%, and 10.6% of the enrolled patients developed severe anemia, severe leukopenia, and severe thrombocytopenia, respectively. Baseline hemoglobin level < 100 g/L (OR = 5.846, 95% CI: 2.765 ~ 12.363), serum creatinine level > 73.4 µmol/L (OR = 2.573, 95% CI: 1.157 ~ 5.723), AST/ALT ratio > 1.6 (OR = 2.479, 95% CI: 1.167 ~ 5.266), sodium level ≤ 136 mmol/liter (OR = 4.342, 95% CI: 1.747 ~ 10.789), and a dose of amphotericin B deoxycholate > 0.58 mg/kg/d (OR = 2.504, 95% CI:1.066 ~ 5.882) were observed to be independent risk factors associated with the development of severe anemia. Co-infection with tuberculosis (OR = 3.307, 95% CI: 1.050 ~ 10.420), and platelet level (per 10 × 109 /L) (OR = 0.952, 95% CI: 0.911 ~ 0.996) were shown to be independent risk factors associated with the development of severe leukopenia. Platelet level < 100 × 109 /L (OR = 2.935, 95% CI: 1.075 ~ 8.016) was identified as the independent risk factor associated with the development of severe thrombocytopenia. There was no difference in progression to severe anemia, severe leukopenia, and severe thrombocytopenia between the patients with or without fungal clearance at 2 weeks. 10 mg on the first day of amphotericin B deoxycholate was calculated to be independent risk factors associated with the development of severe anemia (OR = 2.621, 95% CI: 1.107 ~ 6.206). The group receiving a starting amphotericin B dose (10 mg, 20 mg, daily) exhibited the highest fungal clearance rate at 96.3%, which was significantly better than the group receiving a starting amphotericin B dose (5 mg, 10 mg, 20 mg, daily) (60.9%) and the group receiving a starting amphotericin B dose (5 mg, 15 mg, and 25 mg, daily) (62.9%). CONCLUSION: The preceding findings reveal risk factors for severe anemia, severe leukopenia, and severe thrombocytopenia. After treatment with Amphotericin B, these severe adverse events are likely unrelated to fungal clearance at 2 weeks. Starting amphotericin B deoxycholate at a dose of 10 mg on the first day may increase the risk of severe anemia but can lead to earlier fungal clearance. TRIAL REGISTRATION: ChiCTR1900021195. Registered 1 February 2019.


Assuntos
Anemia , Infecções por HIV , Leucopenia , Trombocitopenia , Humanos , Anfotericina B/efeitos adversos , Antifúngicos/uso terapêutico , Estudos Prospectivos , Quimioterapia de Indução , Anemia/induzido quimicamente , Anemia/tratamento farmacológico , Leucopenia/induzido quimicamente , Leucopenia/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico
12.
Clin Lab ; 69(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37702666

RESUMO

BACKGROUND: Thiamine responsive megaloblastic anemia (TRMA) is a genetic disease caused by SLC19A2 gene mutation. This study aimed to preliminarily explore the relationship between endoplasmic reticulum stress (ERS)-PERK signaling pathway and the pathogenesis of hyperglycemia induced by TRMA. METHODS: Islet ß (INS.1 and ß-TC-6) and HEK293T cell line models with stable overexpression of SLC19A2 and SLC19A2 (c.1409insT) were established. The cells were divided into empty virus group (control), wild-type group (overexpressed SLC19A2), and mutation group (overexpressed SLC19A2 (c.1409insT)). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were used to detect the expression levels of ERS-PERK signaling pathway-related proteins, including glucose-regulated protein 78 (GRP78), protein kinase R-like ER kinase (PERK), and eukaryotic initiation factor 2 (eIF2α), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP) in islet ß cells. Protein localization was assessed by immunofluorescence staining. RESULTS: Compared with the control group, the mRNA expression levels of SLC19A2 in wild-type and mutant islet ß cells (INS.1 and ß-TC-6) and HEK293T cells were significantly upregulated (all p < 0.05). Compared with the control group and the wild-type group, the mRNA expression levels of GRP78, PERK, eIF2α, ATF4, and CHOP were increased (all p < 0.05) in the mutant islet ß cells; the protein expression levels of PERK, GRP78, and eIF2α were elevated (all p < 0.05). In addition, the results of immunofluorescence staining showed that SLC19A2 (c.1409insT) mutation changed the localization of the proteins in the cells. Thus, they were not located on the cell surface, but in the cytoplasm and nuclei, and protein aggregation occurred in the cytoplasm. CONCLUSIONS: 1. Islet ß and HEK293Tcell lines, stably overexpressing SLC19A2 and SLC19A2 (c.1409insT) mutations, were successfully constructed. 2. SLC19A2 (c.1409insT) mutation could raise the expression levels of ERS-PERK signaling pathway-related proteins (GRP78, PERK, eIF2α, ATF4, and CHOP), and activate apoptosis pathway. 3. SLC19A2 (c.1409insT) mutation could change the localization of proteins and produce protein aggregation in cells. It could lead to protein misfolding and ERS, which would participate in the pathological mechanism of hyperglycemia induced by TRMA.


Assuntos
Anemia Perniciosa , Hiperglicemia , Humanos , Chaperona BiP do Retículo Endoplasmático , Células HEK293 , Agregados Proteicos , Hiperglicemia/genética , Estresse do Retículo Endoplasmático/genética , Tiamina , RNA Mensageiro , Proteínas de Membrana Transportadoras
13.
Adv Exp Med Biol ; 1422: 89-119, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36988878

RESUMO

Elevated low-density lipoprotein (LDL) cholesterol (LDLc) is one of the most well-established risk factors for cardiovascular disease, while high levels of high-density lipoprotein (HDL) cholesterol (HDLc) have been associated with protection from cardiovascular disease. Cardiovascular disease remains one of the leading causes of death worldwide; thus it is important to understand mechanisms that impact LDLc and HDLc metabolism. In this chapter, we will discuss molecular processes by which phosphatidylinositol-(4,5)-bisphosphate, PI(4,5)P2, is thought to modulate LDLc or HDLc. Section 1 will provide an overview of cholesterol in the circulation, discussing processes that modulate the various forms of lipoproteins (LDL and HDL) carrying cholesterol. Section 2 will describe how a PI(4,5)P2 phosphatase, transmembrane protein 55B (TMEM55B), impacts circulating LDLc levels through its ability to regulate lysosomal decay of the low-density lipoprotein receptor (LDLR), the primary receptor for hepatic LDL uptake. Section 3 will discuss how PI(4,5)P2 interacts with apolipoprotein A-I (apoA1), the key apolipoprotein on HDL. In addition to direct mechanisms of PI(4,5)P2 action on circulating cholesterol, Sect. 4 will review how PI(4,5)P2 may indirectly impact LDLc and HDLc by affecting insulin action. Last, as cholesterol is controlled through intricate negative feedback loops, Sect. 5 will describe how PI(4,5)P2 is regulated by cholesterol.


Assuntos
Doenças Cardiovasculares , Humanos , LDL-Colesterol , Colesterol , HDL-Colesterol , Lipoproteínas
14.
Int J Mol Sci ; 24(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569437

RESUMO

Over half of the world's population relies on rice as their staple food. The brown planthopper (Nilaparvata lugens Stål, BPH) is a significant insect pest that leads to global reductions in rice yields. Breeding rice varieties that are resistant to BPH has been acknowledged as the most cost-effective and efficient strategy to mitigate BPH infestation. Consequently, the exploration of BPH-resistant genes in rice and the development of resistant rice varieties have become focal points of interest and research for breeders. In this review, we summarized the latest advancements in the localization, cloning, molecular mechanisms, and breeding of BPH-resistant rice. Currently, a total of 70 BPH-resistant gene loci have been identified in rice, 64 out of 70 genes/QTLs were mapped on chromosomes 1, 2, 3, 4, 6, 8, 10, 11, and 12, respectively, with 17 of them successfully cloned. These genes primarily encode five types of proteins: lectin receptor kinase (LecRK), coiled-coil-nucleotide-binding-leucine-rich repeat (CC-NB-LRR), B3-DNA binding domain, leucine-rich repeat domain (LRD), and short consensus repeat (SCR). Through mediating plant hormone signaling, calcium ion signaling, protein kinase cascade activation of cell proliferation, transcription factors, and miRNA signaling pathways, these genes induce the deposition of callose and cell wall thickening in rice tissues, ultimately leading to the inhibition of BPH feeding and the formation of resistance mechanisms against BPH damage. Furthermore, we discussed the applications of these resistance genes in the genetic improvement and breeding of rice. Functional studies of these insect-resistant genes and the elucidation of their network mechanisms establish a strong theoretical foundation for investigating the interaction between rice and BPH. Furthermore, they provide ample genetic resources and technical support for achieving sustainable BPH control and developing innovative insect resistance strategies.

15.
J Neuroradiol ; 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37774912

RESUMO

BACKGROUND: Parkinson's disease (PD) is characterized by loss of selectively vulnerable neurons within the basal ganglia circuit and progressive atrophy in subcortical and cortical regions. However, the impact of neurodegenerative pathology on the topological organization of cortical morphological networks has not been explored. The aims of this study were to investigate altered network patterns of covariance in cortical thickness and complexity, and to evaluate how morphological network integrity in PD is related to motor impairment. METHODS: Individual morphological networks were constructed for 50 PD patients and 46 healthy controls (HCs) by estimating interregional similarity distributions in surface-based indices. We performed graph theoretical analysis and network-based statistics to detect PD-related alterations and further examined the correlation of network metrics with clinical scores. Furthermore, support vector regression based on topological characteristics was applied to predict the severity of motor impairment in PD. RESULTS: Compared with HCs, PD patients showed lower local efficiency (p = 0.004), normalized characteristic path length (p = 0.022), and clustering coefficient (p = 0.005) for gyrification index-based morphological brain networks. Nodal topological abnormalities were mainly in the frontal, parietal and temporal regions, and impaired morphological connectivity was involved in the sensorimotor and default mode networks. The support vector regression model using network-based features allowed prediction of motor symptom severity with a correlation coefficient of 0.606. CONCLUSIONS: This study identified a disrupted topological organization of cortical morphological networks that could substantially advance our understanding of the network degeneration mechanism of PD and might offer indicators for monitoring disease progression.

16.
J Biol Chem ; 297(4): 101183, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34509475

RESUMO

Sentrin/small ubiquitin-like modifier (SUMO)-specific protease 2 (SENP2)-deficient mice develop spontaneous seizures in early life because of a marked reduction in M currents, which regulate neuronal membrane excitability. We have previously shown that hyper-SUMOylation of the Kv7.2 and Kv7.3 channels is critically involved in the regulation of the M currents conducted by these potassium voltage-gated channels. Here, we show that hyper-SUMOylation of the Kv7.2 and Kv7.3 proteins reduced binding to the lipid secondary messenger PIP2. CaM1 has been shown to be tethered to the Kv7 subunits via hydrophobic motifs in its C termini and implicated in the channel assembly. Mutation of the SUMOylation sites on Kv7.2 and Kv7.3 specifically resulted in decreased binding to CaM1 and enhanced CaM1-mediated assembly of Kv7.2 and Kv7.3, whereas hyper-SUMOylation of Kv7.2 and Kv7.3 inhibited channel assembly. SENP2-deficient mice exhibited increased acetylcholine levels in the brain and the heart tissue because of increases in the vagal tone induced by recurrent seizures. The SENP2-deficient mice develop seizures followed by a period of sinus pauses or atrioventricular conduction blocks. Chronic administration of the parasympathetic blocker atropine or unilateral vagotomy significantly prolonged the life of the SENP2-deficient mice. Furthermore, we showed that retigabine, an M-current opener, reduced the transcription of SUMO-activating enzyme SAE1 and inhibited SUMOylation of the Kv7.2 and Kv7.3 channels, and also prolonged the life of SENP2-deficient mice. Taken together, the previously demonstrated roles of PIP2, CaM1, and retigabine on the regulation of Kv7.2 and Kv7.3 channel function can be explained by their roles in regulating SUMOylation of this critical potassium channel.


Assuntos
Cisteína Endopeptidases/metabolismo , Canal de Potássio KCNQ2/metabolismo , Canal de Potássio KCNQ3/metabolismo , Sistemas do Segundo Mensageiro , Sumoilação , Motivos de Aminoácidos , Animais , Encéfalo/metabolismo , Cisteína Endopeptidases/genética , Canal de Potássio KCNQ2/genética , Canal de Potássio KCNQ3/genética , Camundongos , Camundongos Mutantes , Miocárdio/metabolismo , Convulsões/genética , Convulsões/metabolismo , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismo
17.
Clin Infect Dis ; 74(11): 1953-1965, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34390330

RESUMO

BACKGROUND: Follow-up study of coronavirus disease 2019 (COVID-19) survivors has rarely been reported. We aimed to investigate longitudinal changes in the characteristics of COVID-19 survivors after discharge. METHODS: A total of 594 COVID-19 survivors discharged from Tongji Hospital in Wuhan from February 10 to April 30, 2020 were included and followed up until May 17, 2021. Laboratory and radiological findings, pulmonary function tests, electrocardiogram, symptoms and signs were analyzed. RESULTS: 257 (51.2%) patients had at least one symptom at 3 months post-discharge, which decreased to 169 (40.0%) and 138 (28.4%) at 6-month and 12-month visit respectively. During follow-up period, insomnia, chest tightness, and fatigue were the most prevalent symptoms. Most laboratory parameters returned to normal, whereas increased incidence of abnormal liver and renal function and cardiovascular injury was evidenced after discharge. Fibrous stripes (213; 42.4%), pleural thickening and adhesions (188; 37.5%) and enlarged lymph nodes (120; 23.9%) were the most common radiographical findings at 3 months post-discharge. The abnormalities of pulmonary function included obstructive, restrictive, and mixed, which were 5.5%, 4.0%, 0.9% at 6 months post, and 1.9%, 4.7%, 0.2% at 12 months. Electrocardiogram abnormalities occurred in 256 (51.0%) patients at 3 months post-discharge, including arrhythmia, ST-T change and conduction block, which increased to 258 (61.1%) cases at 6-month visit and were maintained at high frequency (242;49.8%) at 12-month visit. CONCLUSIONS: Physiological, laboratory, radiological, or electrocardiogram abnormalities, particularly those related to renal, cardiovascular, and liver functions are common in patients who recovered from coronavirus disease 2019 (COVID-19) up to 12 months post-discharge.


Assuntos
COVID-19 , Assistência ao Convalescente , China/epidemiologia , Seguimentos , Hospitais , Humanos , Alta do Paciente , Estudos Prospectivos , SARS-CoV-2
18.
Biochem Biophys Res Commun ; 636(Pt 1): 162-169, 2022 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-36334440

RESUMO

Primary cilia transduce signals via transmembrane and membrane-associated proteins localized to the ciliary membrane in vertebrate cells. In humans, transmembrane protein 67 (TMEM67), a component of the multiprotein complex functioning as a gatekeeper at the transition zone (TZ) of primary cilia, is mutated in patients suffering from cilia-related pleiotropic diseases, collectively referred to as ciliopathies. The requirement of TMEM67 for the gating function of the TZ that delivers membrane proteins into the ciliary compartment has not been determined. In this study, we established hTERT-RPE1 cells with knockout (KO) of TMEM67 and examined whether cilium formation and TZ gating are affected by its ablation. TMEM67-KO cells displayed impaired ciliogenesis, elongated cilia, perturbed ciliary localization of membrane-associated proteins ARL13B and INPP5E but normal recruitment of TZ proteins CEP290, RPGRIP1L and NPHP5. The exogenous expression of ciliopathy-associated TMEM67 mutants restored ciliary localization of ARL13B and INPP5E but failed to attenuate aberrant cilium elongation in TMEM67-KO cells. Furthermore, we found that TMEM67 localization is not confined to the TZ but extends into the cilium. Our findings indicate that TMEM67 is required not only for ciliogenesis and cilium length regulation but also for the gating function of the TZ independently of RPGRIP1L/CEP290/NPHP5 recruitment to this region. They further suggest that aberrant cilium elongation underlies the pathogenesis of TMEM67-linked ciliopathies.


Assuntos
Cílios , Ciliopatias , Humanos , Cílios/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Antígenos de Neoplasias/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fatores de Ribosilação do ADP/metabolismo
19.
HIV Med ; 23 Suppl 1: 6-13, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35293100

RESUMO

OBJECTIVES: Although antiretroviral therapy (ART) has prolonged the lives of HIV-infected individuals, HIV reservoir remains the main stumbling block to HIV cure. Presently, early ART initiation is one of the effective measures to reduce the HIV reservoir. The effects of ART in Chinese individuals with acute and early HIV infection (AEHI) and chronic HIV infection (CHI) were analyzed in this study. METHODS: We performed virological and immunological parameter analysis in 29 AEHI and 19 CHI individuals who were initiated into ART in Beijing, China. The HIV DNA, CD4+ T-cell and CD8+ T-cell counts, and CD4/CD8 ratios between the two groups were compared using statistical analyses. RESULTS: At weeks 48 and 96, the total HIV DNA was significantly lower in the AEHI group than that the CHI group (2.48 [2.26-2.66] vs. 3.06 [2.79-3.33] log10 copies/106 peripheral blood mononuclear cells (PBMCs), p < 0.01 at week 48 and 2.17 [1.85-2.45] vs. 2.92 [2.73-3.24] log10 copies/106  PBMCs, p < 0.01 at week 96, respectively). The CD4/CD8 T-cell ratio in the AHI group at week 24 was significantly higher than that in the CHI group (0.71 [0.50-0.99] vs. 0.45 [0.34-0.65], p = 0.08). After 48 weeks of ART, there was still a negative correlation between the CD4/CD8 ratio and the HIV DNA level in the CHI group rather than the AEHI group. CONCLUSIONS: Early ART initiation could enhance an earlier immunological recovery in AEHI. Immunological normalization after ART initiation could provide important protection against the viral reservoir seeded in AEHI individuals.


Assuntos
Infecções por HIV , HIV-1 , DNA Viral , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Leucócitos Mononucleares , Carga Viral
20.
FASEB J ; 35(4): e21510, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33710677

RESUMO

Neurological diseases are relatively complex diseases of a large system; however, the detailed mechanism of their pathogenesis has not been completely elucidated, and effective treatment methods are still lacking for some of the diseases. The SUMO (small ubiquitin-like modifier) modification is a dynamic and reversible process that is catalyzed by SUMO-specific E1, E2, and E3 ligases and reversed by a family of SENPs (SUMO/Sentrin-specific proteases). SUMOylation covalently conjugates numerous cellular proteins, and affects their cellular localization and biological activity in numerous cellular processes. A wide range of neuronal proteins have been identified as SUMO substrates, and the disruption of SUMOylation results in defects in synaptic plasticity, neuronal excitability, and neuronal stress responses. SUMOylation disorders cause many neurodegenerative diseases, such as Parkinson's disease, Alzheimer's disease, and Huntington's disease. By modulating the ion channel subunit, SUMOylation imbalance is responsible for the development of various channelopathies. The regulation of protein SUMOylation in neurons may provide a new strategy for the development of targeted therapeutic drugs for neurodegenerative diseases and channelopathies.


Assuntos
Doenças do Sistema Nervoso/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sumoilação/fisiologia , Animais , Endopeptidases/metabolismo , Humanos , Proteína SUMO-1/metabolismo
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