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1.
Exp Cell Res ; 440(1): 114117, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38848952

RESUMO

PURPOSE: Membrane associated ubiquitin ligase MARCH2 majorly involves in inflammation response and protein trafficking. However, its comprehensive role in hepatocellular carcinoma (HCC) is largely unknown. METHODS: Firstly, multiple bioinformatic analyses were applied to determine MARCH2 mRNA level, its expression comparison in diverse molecular and immune subtypes, and diagnostic value in HCC. Subsequently, RNA-seq, real-time quantitative PCR, immunohistochemistry and cell proliferation assay are used to explore the epithelial-mesenchymal transition (EMT) and proliferation by gene-silencing or overexpressing in cultured HCC cells or in vivo xenograft. Moreover, dual luciferase reporter assay and immunoblotting are delved into verify the transcription factor that activating MARCH2 promoter. RESULTS: Multiple bioinformatic analyses demonstrate that MARCH2 is upregulated in multiple cancer types and exhibits startling diagnostic value as well as distinct molecular and immune subtypes in HCC. RNA-seq analysis reveals MARCH2 may promote EMT, cell proliferation and migration in HepG2 cells. Furthermore, overexpression of MARCH2 triggers EMT and significantly enhances HCC cell migration, proliferation and colony formation in a ligase activity-dependent manner. Additionally, above observations are validated in the HepG2 mice xenografts. For up-stream mechanism, transcription factor KLF15 is highly expressed in HCC and activates MARCH2 expression. CONCLUSION: KLF15 activated MARCH2 triggers EMT and serves as a fascinating biomarker for precise diagnosis of HCC. Consequently, MARCH2 emerges as a promising candidate for target therapy in cancer management.


Assuntos
Carcinoma Hepatocelular , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like , Neoplasias Hepáticas , Ubiquitina-Proteína Ligases , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Transição Epitelial-Mesenquimal/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico , Proliferação de Células/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Camundongos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Movimento Celular/genética , Células Hep G2 , Camundongos Nus , Camundongos Endogâmicos BALB C , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Masculino , Feminino
2.
Nano Lett ; 24(4): 1415-1422, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232178

RESUMO

Charge and spin are two intrinsic attributes of carriers governing almost all of the physical processes and operation principles in materials. Here, we demonstrate the manipulation of electronic and spin states in designed Co-quantum dot/WS2 (Co-QDs/WS2) heterostructures by employing a metal-dielectric composite substrate and via scanning tunneling microscope. By repeatedly scanning under a unipolar bias, switching the bias polarity, or applying a pulse through nonmagnetic or magnetic tips, the Co-QDs morphologies exhibit a regular and reproducible transformation between bright and dark dots. First-principles calculations reveal that these tunable characters are attributed to the variation of density of states and the transition of magnetic anisotropy energy induced by carrier accumulation. It also suggests that the metal-dielectric composite substrate is successful in creating the interfacial potential for carrier accumulation and realizes the electrically controllable modulations. These results will promote the exploration of electron-matter interactions in quantum systems and provide an innovative way to facilitate the development of spintronics.

3.
Neurochem Res ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822984

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis. METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis. RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment. CONCLUSION: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.

4.
J Bioenerg Biomembr ; 55(2): 103-114, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37046136

RESUMO

Endothelial dysfunction is a key early link in the pathogenesis of atherosclerosis, and the accumulation of senescent vascular endothelial cells causes endothelial dysfunction. Phosphoenolpyruvate (PEP), which is a high-energy glycolytic intermediate, protects against ischemia-reperfusion injury in isolated rat lung, heart, and liver tissue by quickly providing ATP. However, it was reported that serum PEP concentrations are 13-fold higher in healthy elderly compare to the young. Unlike that of other cell types, the energy required for the physiological function of endothelial cells is mainly derived from glycolysis. Recently, it is unclear whether circulating accumulation of PEP affects endothelial cell function. In this study, we found for the first time that 50-250 µM of PEP significantly promoted THP-1 monocyte adhesion to human umbilical vein endothelial cells (HUVECs) through increased expression of vascular endothelial adhesion factor 1 (VCAM1) and intercellular adhesion factor 1 (ICAM1) in HUVECs. Meanwhile, 50-250 µM of PEP decreased the expression of endothelial nitric oxide synthase (eNOS) and cellular level of nitric oxide (NO) in HUVECs. Moreover, PEP increased levels of ROS, enhanced the numbers of SA-ß-Gal-positive cells and upregulated the expression of cell cycle inhibitors such as p21, p16 and the phosphorylation level of p53 on Ser15, and the expression of proinflammatory factors including TNF-α, IL-1ß, IL-6, IL-8, IL-18 and MCP-1 in HUVECs. Furthermore, PEP increased both oxygen consumption rate (OCR) and glycolysis rate, and was accompanied by reduced NAD+/NADH ratios and enhanced phosphorylation levels of AMPKα (Thr172), p38 MAPK (T180/Y182) and NF-κB p65 (Ser536) in HUVECs. Notably, PEP had no significant effect on hepG2 cells. In conclusion, these results demonstrated that PEP induced dysfunction and senescence in vascular endothelial cells through stimulation of metabolic reprogramming.


Assuntos
Senescência Celular , Transdução de Sinais , Ratos , Animais , Humanos , Idoso , Células Cultivadas , Fosfoenolpiruvato/metabolismo , Fosfoenolpiruvato/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia
5.
BMC Anesthesiol ; 23(1): 299, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670239

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) has been reported as a significant complication in elderly patients. Various methods have been proposed for reducing the incidence and severity of POCD. Intravenous lidocaine administration has been reported in the literature to reduce POCD, but the effect of lidocaine remains controversial. METHODS: We screened Medline, Embase, Cochrane Library, and China National Knowledge Infrastructure (up to April 2022) databases following a search strategy for intravenous lidocaine on POCD. We also screened related bibliographies on lidocaine for POCD. Ten articles comprising 1517 patients were selected and analyzed. We divided the postoperative follow-up period as follows: short term (<30 days), medium term (30-90 days), and long term (>90 days). OUTCOMES: We found that lidocaine could attenuate the overall incidence of POCD, especially in the short term. There were no differences between lidocaine and placebo on the overall severity of POCD. CONCLUSION: Lidocaine administered intravenously could attenuate the overall incidence of POCD and its severity in the short term.


Assuntos
Complicações Cognitivas Pós-Operatórias , Idoso , Humanos , Administração Intravenosa , China , Bases de Dados Factuais , Lidocaína
6.
Biochem Biophys Res Commun ; 612: 169-175, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35533489

RESUMO

Hepatic lipid accumulation is an initiation factor in fatty liver disease, and promoting a reduction in hepatic lipid accumulation is an important treatment strategy. DEAD box RNA helicase 17 (DDX17) is a member of the DEAD-box family and a molecular chaperone. Previous studies have demonstrated that DDX17 is a transcriptional coregulator of tumorigenesis, inflammation, and macrophage cholesterol efflux. The liver is the main site for lipid metabolism, and metabolic (dysfunction)-associated fatty liver disease (MAFLD) is one of the most common chronic liver diseases. However, the impact of DDX17 on hepatic lipid accumulation has not been verified. In this study, we found, for the first time, that oleic acid/palmitic acid (OA/PA)-induced lipid accumulation was largely abrogated by DDX17 overexpression in both HepG2 (a human hepatocellular carcinoma line) and Hep1-6 (a murine hepatocellular carcinoma line) cells, and this effect was due to a marked reduction in cellular triglyceride (TG) content. Moreover, the overexpression of DDX17 was accompanied by a significant decrease in the expression of genes involved in de novo fatty acid synthesis (FAS, ACC, and SCD-1) in both HepG2 and Hep1-6 cells. In conclusion, DDX17 protected against OA/PA-induced lipid accumulation in hepatocytes through de novo lipogenesis inhibition.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Carcinoma Hepatocelular/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos , Lipogênese , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido Oleico/metabolismo , Ácido Oleico/farmacologia , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacologia
7.
Eur Radiol ; 32(1): 254-261, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34255162

RESUMO

OBJECTIVES: To compare the correlation of depth of invasion (DOI) measured on multiple magnetic resonance imaging (MRI) sequences and pathological DOI, in order to determine the optimal MRI sequence for measurement. METHODS: A total of 122 oral tongue squamous cell carcinoma (OTSCC) patients were retrospectively analyzed, who had received preoperative MRI and surgical resection. DOIs measured on fat-suppressed T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), dynamic enhanced-T1 high-resolution insotropic volume examination (e-THRIVE), and contrast-enhanced fat-suppressed T1WI (CE-T1WI) were respectively compared to those measured in pathologic specimens. The cutoff value of the best correlated MRI sequence was determined, and the T staging accuracy of MRI-derived DOI was evaluated. RESULTS: DOI derived from e-THRIVE showed the best correlation (r = 0.936, p < 0.001) with pathological DOI. The area under the curve values of MRI-derived DOI distinguishing T1 stage from T2 stage and distinguishing T2 stage from T3 stage were 0.969 and 0.974, respectively. The T staging criteria of MRI-derived DOI were 6.2 mm and 11.4 mm, with a staging accuracy of 86.9% compared to pathological DOI criteria of 5 mm and 10 mm. CONCLUSION: E-THRIVE was the optimal MR sequence to measure the MR-derived DOI, and DOI derived from e-THRIVE could serve as a potential cut-off value as a clinical T staging indicator of OTSCC. KEY POINTS: • Multiparametric MRI helps radiologists to assess the neoplasm invasion in patients with oral tongue squamous cell carcinoma. • Retrospective study indicated that measurement was most accurate on enhanced-T1 high-resolution insotropic volume examination dynamic contrast enhancement images. • T staging of oral tongue squamous cell carcinoma was accurate according to the dynamic contrast enhancement MRI-derived depth of invasion.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Língua , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/patologia
8.
Acta Radiol ; 62(9): 1163-1169, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32972214

RESUMO

BACKGROUND: Bell's palsy (BP) is the most common form of acute facial nerve disorder and is characterized by rapid onset peripheral facial palsy of unknown etiology. PURPOSE: To explore the diagnostic value of dynamic contrast-enhanced (DCE) magnetic resonance imagine (MRI) in patients with BP particularly in involved segments. MATERIAL AND METHODS: A retrospective analysis was performed on the patients with BP who underwent routine MRI examinations and volumetric interpolated breath-hold examination (VIBE) sequence-based DCE-MRI before surgery in our department from January 2015 to July 2020. DCE-MRI data postprocessing was performed on Siemens Workstation Extended MR Work Space 2.6.3.5. Statistical analyses were performed using SPSS®v.19.0. The inter-observer reliability was evaluated with kappa identity test and McNemar's test. RESULTS: Twenty-three patients were included. On conventional contrast-enhanced MRI, the two observers were inconsistent in their diagnosis of lesion segments of facial nerve (Kappa 0.426, P = 0.009). Compared to the results of the surgery, the diagnostic consistency of both observers was general (Kappa 0.476, P < 0.001 and Kappa 0.430, P < 0.001, respectively). The diagnostic results of DCE-MRI for lesion segments of the facial nerve were consistent between the two observers (Kappa 0.929, P < 0.001). Compared to the results of the surgery, the diagnostic consistency of both observers was good (Kappa 0.753, P < 0.001 and Kappa 0.731, P < 0.001, respectively). CONCLUSION: Compared to conventional MRI, DCE-MRI has good stability and repeatability in the diagnosis of the lesion segments of the facial nerve as well as a good specificity and accuracy.


Assuntos
Paralisia de Bell/diagnóstico por imagem , Meios de Contraste , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
9.
Biochem Biophys Res Commun ; 523(1): 140-146, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-31837803

RESUMO

Doxorubicin, as a first line chemotherapeutic agent, its usage is limited owing to cardiotoxicity. Necroptosis is a new form of programmed cell death, and recent investigations indicated that necroptosis is vitally involved in serious cardiac pathological conditions. Dexrazoxane is the only cardiac protective drug approved by FDA for anthracycline. We aimed to explore whether and how dexrazoxane regulates doxorubicin-induced cardiomyocyte necroptosis. First, doxorubicin could cause heart failure and reduce cardiomyocyte viability by promoting cell apoptosis and necroptosis in vivo and in vitro. Second, necroptosis plays an important role in doxorubicin induced cardiomyocyte injury, which could be inhibited by Nec-1. Third, dexrazoxane increased cell viability and protect heart function by decreasing both cardiomyocyte apoptosis and necroptosis after doxorubicin treatment. Forth, dexrazoxane attenuated doxorubicin-induced inflammation and necroptosis by the inhibition of p38MAPK/NF-κB pathways. These results indicated that dexrazoxane ameliorates cardiotoxicity and protects heart function by attenuating both apoptosis and necroptosis in doxorubicin induced cardiomyocyte injury.


Assuntos
Apoptose/efeitos dos fármacos , Dexrazoxano/farmacologia , Doxorrubicina/efeitos adversos , Miócitos Cardíacos/efeitos dos fármacos , Necroptose/efeitos dos fármacos , Animais , Células Cultivadas , Dexrazoxano/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Relação Estrutura-Atividade
10.
Biochem Biophys Res Commun ; 499(3): 626-633, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29601818

RESUMO

BACKGROUND AND AIMS: Niemann-Pick C1-like1 (NPC1L1), a crucial cholesterol absorption receptor expressed in human intestine and liver. But in mouse it is only expressed in intestine. Previous studies elucidated that expression of human NPC1L1 in mouse liver led to increase of plasma cholesterol due to activation of absorption from bile. However, hepatic NPC1L1 function was not elucidated in LDL receptor deficient mouse (LDLR-/-) in which LDL was a main lipoprotein as in human. METHODS AND RESULTS: L1-Tg/LDLR-/- mouse was created by crossing liver-specific NPC1L1 transgenic mouse (L1-Tg) with LDLR-/-. L1-Tg/LDLR-/- mice developed hyperlipidemia when fed with atherogenic diet (AD) containing 0.2% cholesterol for 21days. Compared with control mice, biliary cholesterol level in L1-Tg/LDLR-/- mice was significantly lower, plasma cholesterol level was significantly higher in L1-Tg/LDLR-/- mice under both chow diet and AD feeding. New finding in this study is augmentations of plasma TAG L1-Tg/LDLR-/- mice fed with AD. Results were shown that very low density lipoprotein (VLDL) secretion was elevated in L1-Tg/LDLR-/- mice after AD fed. The increase of VLDL secretion was further confirmed by higher expression of hepatic triacylglycerol hydrolase (TGH) and microsomal triglyceride transfer protein (MTP). CONCLUSION: L1-Tg/LDLR-/- mouse is a humanized model to study cholesterol absorption and transportation. The results obtained from L1-Tg/LDLR-/- mouse indicated no feedback mechanism to inhibit NPC1L1 function in liver and hepatic expression of NPC1L1 correlated with VLDL secretion in hypercholesterolemia state.


Assuntos
Hiperlipidemias/metabolismo , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Receptores de LDL/deficiência , Animais , Aterosclerose/patologia , Ácidos e Sais Biliares/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Dieta , Fezes , Comportamento Alimentar , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/patologia , Lipoproteínas HDL/metabolismo , Lipoproteínas VLDL/sangue , Fígado/patologia , Proteínas de Membrana Transportadoras , Camundongos Knockout , Camundongos Transgênicos , Receptores de LDL/metabolismo , Receptores de Lipoproteínas/metabolismo , Triglicerídeos/sangue
11.
Radiol Med ; 123(7): 481-488, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29508241

RESUMO

OBJECTIVE: To investigate the therapeutic efficacy of Iodine-125 (125I) seeds brachytherapy to pancreatic ductal adenocarcinoma (PDAC) xenografts via multiparametric magnetic resonance imaging (MRI) analysis. MATERIALS AND METHODS: Twenty mice were implanted subcutaneously with SW-1990 PDAC xenografts. The tumor-bearing mice were randomly divided into 125I seeds group (n = 10) and blank control group (n = 10). Treatment response was monitored by diffusion-weighted magnetic resonance imaging (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) obtained 1 day before, 14 and 60 days after treatment. Imaging results were correlated with histopathology. RESULTS: 125I seeds brachytherapy resulted in a significant increase in mean tumor apparent diffusion coefficient (ADC) values compared to the control at 14 and 60 days after treatment (p < 0.05). DCE-MRI showed a significant decrease in the perfusion parameters including Ktrans and Kep (p < 0.05). The mean ADCs within the peripheral region of the tumors were linearly proportional to the mean apoptotic cell density (p = 0.015; Spearman's coefficient = 0.945). The Ktrans and Kep were linearly proportional to microvessel density (MVD) (p = 0.043, 0.047; Spearman's coefficient = 0.891, 0.884). CONCLUSION: 125I seeds brachytherapy leads to effective inhibition of PDAC cell proliferation, higher degree of necrosis and necroptosis, and lower MVD. Both DW-MRI and DCE-MRI are feasible to monitor a response to 125I seeds brachytherapy in the PDAC xenografts. This paper shows an original project concerning about a possible palliative treatment not only in a murine model (preclinical setting) but also in humans.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/radioterapia , Braquiterapia , Meios de Contraste , Radioisótopos do Iodo/uso terapêutico , Imageamento por Ressonância Magnética , Ductos Pancreáticos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Animais , Imagem de Difusão por Ressonância Magnética , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Resultado do Tratamento
12.
J Biol Chem ; 291(20): 10625-34, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27013659

RESUMO

In a microarray study, we found that hepatic miR-291b-3p was significantly increased in leptin-receptor-deficient type 2 mice (db/db), a mouse model of diabetes. The function of miR-291b-3p is unknown. The potential role of miR-291b-3p in regulating hepatic lipid metabolism was explored in this study. High-fat diet (HFD)- and chow-fed mice were injected with an adenovirus expressing a miR-291b-3p inhibitor and a miR-291b-3p mimic through the tail vein. Hepatic lipids and lipogenic gene expression were analyzed. Additionally, gain- and loss-of-function studies were performed in vitro to identify direct targets of miR-291b-3p. MiR-291b-3p expression and the protein levels of sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FAS) were increased in the steatotic liver of db/db mice and HFD-fed mice versus their respective controls. Inhibition of hepatic miR-291b-3p expression prevented increases in hepatic lipogenesis and steatosis in HFD-fed mice. The opposite was observed when miR-291b-3p was overexpressed in the livers of chow-fed C57BL/6J wild-type mice. In vitro studies revealed that silencing of miR-291b-3p in NCTC1469 hepatic cells ameliorated oleic acid/palmitic acid mixture-induced elevation of cellular triglycerides. Importantly, we identified AMP-activated protein kinase (AMPK)-α1 as a direct target of miR-291b-3p. Using metformin, an activator of AMPK, we showed that AMPK activation-induced inhibition of hepatic lipid accumulation was accompanied by reduced expression of miR-291b-3p in the liver. Liver miR-291b-3p promoted hepatic lipogenesis and lipid accumulation in mice. AMPKα1 is a direct target of miR-291b-3p. In conclusion, our findings indicate that miR-291b-3p promotes hepatic lipogenesis by suppressing AMPKα1 expression and activity, indicating the therapeutic potential of miR-291b-3p inhibitors in fatty liver disease.


Assuntos
Proteínas Quinases Ativadas por AMP/biossíntese , Gorduras na Dieta/efeitos adversos , Fígado Gorduroso/metabolismo , Lipogênese/efeitos dos fármacos , Fígado/metabolismo , MicroRNAs/biossíntese , Proteínas Quinases Ativadas por AMP/genética , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Gorduras na Dieta/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Lipogênese/genética , Fígado/patologia , Metformina/farmacologia , Camundongos , MicroRNAs/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
13.
Cell Physiol Biochem ; 41(6): 2419-2431, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28467989

RESUMO

OBJECTIVE: Insulin resistance is a critical factor contributing to the pathogenesis of type 2 diabetes and other metabolic diseases. Recent studies have indicated that miR-338-3p plays an important role in cancer. Here, we investigated whether miR-338-3p mediates tumour necrosis factor-α (TNF-α)-induced hepatic insulin resistance. METHODS: The activation of the insulin signalling pathway and the level of glycogenesis were examined in the livers of the db/db and high fat diet (HFD)-fed mice and in HEP1-6 cells transfected with miR-338-3p mimic or inhibitor. Computational prediction of microRNA target, luciferase assay and Western blot were used to assess the miR-338-3p target. Chromatin immunoprecipitation (ChIP) assay was used to determine the transcriptional regulator of miR-338-3p. RESULTS: miR-338-3p was down-regulated in the livers of the db/db, HFD-fed and TNF-α-treated C57BL/6J mice, as well as in mouse HEP1-6 hepatocytes treated with TNF-α. Importantly the down-regulation of miR-338-3p induced insulin resistance, as indicated by impaired glucose tolerance and insulin tolerance. Further research showed that the down-regulated miR-338-3p resulted in the impaired AKT/ glycogen synthase kinase 3 beta (GSl·Gß) signalling pathway and glycogen synthesis. In contrast, hepatic over-expression of miR-338-3p rescued the TNF-α-induced insulin resistance. Moreover, protein phosphatase 4 regulator subunit 1 (PP4R1) was identified as a direct target of miR-338-3p that mediated hepatic insulin signalling by regulating protein phosphatase 4 (PP4). Finally we identified hepatic nuclear factor 4 alpha (HNF-4α) as the transcriptional regulator of miRNA-338-3p. CONCLUSIONS: Our studies provide novel insight into the critical role and molecular mechanism by which miR-338-3p is involved in TNF-α-induced hepatic insulin resistance. miR-338-3p might mediate TNF-α-induced hepatic insulin resistance by targeting PP4R1 to regulate PP4 expression.


Assuntos
Regulação da Expressão Gênica , Resistência à Insulina , Fígado/efeitos dos fármacos , MicroRNAs/metabolismo , Fosfoproteínas Fosfatases/genética , Fator de Necrose Tumoral alfa/farmacologia , Animais , Sequência de Bases , Linhagem Celular , Dieta Hiperlipídica , Glicogênio Sintase Quinase 3 beta/metabolismo , Fator 4 Nuclear de Hepatócito/antagonistas & inibidores , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Insulina/farmacologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Transdução de Sinais
14.
Biochem Biophys Res Commun ; 457(3): 440-4, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25592969

RESUMO

Studies have shown that nifedipine, an anti-hypertensive drug, protects against atherosclerotic progression, but the underlying mechanisms remain elusive. Oxidized low-density lipoprotein (ox-LDL) is critically implicated in macrophage lipid deposition seen in atherosclerosis. In this study, we examined the effects of nifedipine on some ox-LDL-associated changes in human blood-derived macrophages. We isolated monocytes from normal human blood and differentiated them into macrophages. We then treated these human macrophages with ox-LDL and/or nifedipine, and examined lipid accumulation and expression levels of two scavenge receptors CD36 and SR-A as well as a protein kinase PKC-θ. Nifedipine treatment substantially reduced lipid accumulation and the expression of CD36, SR-A, and protein kinase C (PKC)-θ in human macrophages treated with ox-LDL. Silencing of PKC-θ using siRNA also reduced the expression of CD36 and SR-A in these cells. Our results thus suggest that nifedipine may inhibit atherosclerosis by reducing ox-LDL-induced lipid deposition through suppression of the CD36/SR-A-mediated uptake of ox-LDL by macrophages via a PKC-θ-dependent mechanism.


Assuntos
Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Nifedipino/farmacologia , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Antígenos CD36/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Células Cultivadas , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Lipoproteínas LDL/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , RNA Interferente Pequeno/genética , Receptores Depuradores Classe A/metabolismo
15.
Cell Physiol Biochem ; 33(3): 810-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24685524

RESUMO

BACKGROUND: There is increasing evidence that miRNAs are involved in cellular apoptosis. However, the specific role of miR-291b-3p in apoptosis has not been elucidated. In the present study, we investigated the effect of miR-291b-3p on NCTC1469 cell growth and apoptosis. METHODS: Cell viability and apoptosis were examined in NCTC1469 cells transfected with miR-291b-3p mimics, inhibitor miRNA or negative control. Using computational miRNA target prediction databases, HuR was predicted as a target of miR-291b-3p. Luciferase assay, immunofluorescence and western blot were used to further explore the effects of miR-291b-3p on HuR expression. In addition, the effect of HuR on cell apoptosis was evaluated using a HuR-specific siRNA. RESULTS: TNF-α-induced hepatocyte apoptosis was accompanied by enhanced expression of miR-291b-3p, suggesting that miR-291b-3p might contribute to the apoptotic process. Follow-up experiments showed that upregulation of miR-291b-3p decreased cell viability and induced NCTC1469 cell apoptosis. Additionally, similar to the activity of miR-519, which is another member of the same miRNA family, miR-291b-3p suppressed HuR translation through binding to the HuR coding region (CR). We further showed that the downregulation of HuR expression by miR-291b-3p was accompanied by reduced Bcl-2 expression. Moreover, knockdown of HuR also impaired Bcl-2 expression and increased the ratio of Bax/Bcl-2. More significantly, downregulation of miR-291b-3p failed to increase Bcl2 expression in NCTC1469 cells that were co-transfected with siRNA-HuR. Finally, inhibition of miR-291b-3p led to reduced apoptosis, while knockdown of HuR by siRNA promoted apoptosis, even in NCTC1469 cells that were co-transfected with the miR-291b-3p inhibitor. CONCLUSION: The current data suggested that miR-291b-3p contributed to NCTC1469 cell apoptosis by regulating the expression of HuR, which in turn increased Bcl-2 stability.


Assuntos
Apoptose/fisiologia , Proteína Semelhante a ELAV 1/biossíntese , Hepatócitos/metabolismo , MicroRNAs/biossíntese , Biossíntese de Proteínas/fisiologia , Regulação para Cima/fisiologia , Animais , Linhagem Celular , Proteína Semelhante a ELAV 1/genética , Hepatócitos/citologia , Masculino , Camundongos , MicroRNAs/genética , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
16.
Drug Des Devel Ther ; 18: 1349-1368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681208

RESUMO

Background: Sepsis is recognized as a multiorgan and systemic damage caused by dysregulated host response to infection. Its acute systemic inflammatory response highly resembles that of lipopolysaccharide (LPS)-induced endotoxemia. Propofol and dexmedetomidine are two commonly used sedatives for mechanical ventilation in critically ill patients and have been reported to alleviate cognitive impairment in many diseases. In this study, we aimed to explore and compare the effects of propofol and dexmedetomidine on the encephalopathy induced by endotoxemia and to investigate whether ferroptosis is involved, finally providing experimental evidence for multi-drug combination in septic sedation. Methods: A total of 218 C57BL/6J male mice (20-25 g, 6-8 weeks) were used. Morris water maze (MWM) tests were performed to evaluate whether propofol and dexmedetomidine attenuated LPS-induced cognitive deficits. Brain injury was evaluated using Nissl and Fluoro-Jade C (FJC) staining. Neuroinflammation was assessed by dihydroethidium (DHE) and DCFH-DA staining and by measuring the levels of three cytokines. The number of Iba1+ and GFAP+ cells was used to detect the activation of microglia and astrocytes. To explore the involvement of ferroptosis, the levels of ptgs2 and chac1; the content of iron, malondialdehyde (MDA), and glutathione (GSH); and the expression of ferroptosis-related proteins were investigated. Conclusion: The single use of propofol and dexmedetomidine mitigated LPS-induced cognitive impairment, while the combination showed poor performance. In alleviating endotoxemic neural loss and degeneration, the united sedative group exhibited the most potent capability. Both propofol and dexmedetomidine inhibited neuroinflammation, while propofol's effect was slightly weaker. All sedative groups reduced the neural apoptosis, inhibited the activation of microglia and astrocytes, and relieved neurologic ferroptosis. The combined group was most prominent in combating genetic and biochemical alterations of ferroptosis. Fpn1 may be at the core of endotoxemia-related ferroptosis activation.


Assuntos
Dexmedetomidina , Endotoxemia , Ferroptose , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Propofol , Dexmedetomidina/farmacologia , Animais , Propofol/farmacologia , Ferroptose/efeitos dos fármacos , Camundongos , Masculino , Endotoxemia/tratamento farmacológico , Endotoxemia/metabolismo , Endotoxemia/induzido quimicamente , Lipopolissacarídeos/farmacologia , Relação Dose-Resposta a Droga , Encefalopatias/tratamento farmacológico , Encefalopatias/metabolismo , Encefalopatias/patologia , Hipnóticos e Sedativos/farmacologia
17.
Signal Transduct Target Ther ; 9(1): 127, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38782919

RESUMO

DEAD-box helicase 17 (DDX17) is a typical member of the DEAD-box family with transcriptional cofactor activity. Although DDX17 is abundantly expressed in the myocardium, its role in heart is not fully understood. We generated cardiomyocyte-specific Ddx17-knockout mice (Ddx17-cKO), cardiomyocyte-specific Ddx17 transgenic mice (Ddx17-Tg), and various models of cardiomyocyte injury and heart failure (HF). DDX17 is downregulated in the myocardium of mouse models of heart failure and cardiomyocyte injury. Cardiomyocyte-specific knockout of Ddx17 promotes autophagic flux blockage and cardiomyocyte apoptosis, leading to progressive cardiac dysfunction, maladaptive remodeling and progression to heart failure. Restoration of DDX17 expression in cardiomyocytes protects cardiac function under pathological conditions. Further studies showed that DDX17 can bind to the transcriptional repressor B-cell lymphoma 6 (BCL6) and inhibit the expression of dynamin-related protein 1 (DRP1). When DDX17 expression is reduced, transcriptional repression of BCL6 is attenuated, leading to increased DRP1 expression and mitochondrial fission, which in turn leads to impaired mitochondrial homeostasis and heart failure. We also investigated the correlation of DDX17 expression with cardiac function and DRP1 expression in myocardial biopsy samples from patients with heart failure. These findings suggest that DDX17 protects cardiac function by promoting mitochondrial homeostasis through the BCL6-DRP1 pathway in heart failure.


Assuntos
RNA Helicases DEAD-box , Insuficiência Cardíaca , Miócitos Cardíacos , Animais , Humanos , Camundongos , Apoptose/genética , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/metabolismo , Homeostase/genética , Camundongos Knockout , Camundongos Transgênicos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Dinâmica Mitocondrial/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo
18.
J Pharm Pharmacol ; 75(2): 253-263, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36179123

RESUMO

OBJECTIVES: To investigate the function and regulatory mechanisms of delphinidin in the treatment of hepatocellular carcinoma. METHODS: HepG2 and HuH-7 cells were treated with different concentrations of delphinidin. Cell viability was analysed by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The cell autophagy and autophagic flux were analysed by LC3b-green fluorescent protein (GFP)-Adv and LC3b-GFP-monomeric red fluorescent protein-Adv transfected HepG2 and HuH-7 cells, respectively. Cell apoptosis was analysed by Hoechst33342 staining, terminal deoxynucleotidyl transferase dUTP nick end labeling staining and DNA laddering. Cell autophagy, apoptosis and survival related protein expressions were detected by Western blotting. KEY FINDINGS: After treatment with different concentrations of delphinidin, the cell survival rate was significantly decreased. Delphinidin could block the autophagic flux, resulting in a significant increase in autophagosomes, and led to an increase in cell apoptosis. The combined application of delphinidin and cisplatin could promote the antitumour effect and reduce the dose of cisplatin in tumour cells. Further mechanism studies reveal that delphinidin could inhibit the multidrug resistance gene 1 (MDR1) and the tumour-promoting transcription cofactor DEAD-box helicase 17 (DDX17) expression in tumour cells. Overexpression of DDX17 could reverse delphinidin's antitumor function in tumour cells. CONCLUSIONS: Delphinidin has a strong anti-tumour effect by inducing tumour cell autophagic flux blockage and apoptosis by inhibiting of both MDR1 and DDX17 expression.


Assuntos
Cisplatino , Neoplasias Hepáticas , Humanos , Cisplatino/farmacologia , Genes MDR , Apoptose , Autofagia , Linhagem Celular Tumoral , RNA Helicases DEAD-box/farmacologia
19.
Eur J Pharmacol ; 944: 175584, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36781043

RESUMO

Apigenin is a natural flavonoid which is widely found in vegetables and fruits. However, the mechanism of apigenin in oxidative stress-induced myocardial injury has not been fully elucidated. We established an isoproterenol (Iso)-induced myocardial injury mouse model and a hypoxia/reoxygenation (H/R)-induced H9c2 cell injury model, followed by pretreatment with apigenin to explore its protective effects. Apigenin can significantly alleviate isoproterenol-induced oxidative stress, cell apoptosis and myocardial remodeling in vivo. Apigenin pretreatment can also significantly improve cardiomyocyte morphology, decrease H/R induced oxidative stress, and attenuate cell apoptosis and inflammation in vitro. Further mechanism study revealed that apigenin treatment reversed isoprenaline and H/R-induced decrease of Sirtuin1 (SIRT1). Molecular docking results proved that apigenin can form hydrogen bond with 230 Glu, a key site of SIRT1 activation, indicating that apigenin is an agonist of SIRT1. Moreover, SIRT1 knockdown by siRNA significantly reversed the protective effect of apigenin in H/R-induced myocardial injury. In conclusion, apigenin protects cardiomyocyte function from oxidative stress-induced myocardial injury by modulating SIRT1 signaling pathway, which provides a new potential therapeutic natural compound for the clinical treatment of cardiovascular diseases.


Assuntos
Apigenina , Sirtuína 1 , Animais , Camundongos , Apigenina/farmacologia , Apoptose , Hipóxia/metabolismo , Isoproterenol/farmacologia , Simulação de Acoplamento Molecular , Miócitos Cardíacos , Estresse Oxidativo , Transdução de Sinais , Sirtuína 1/metabolismo
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