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1.
Artigo em Inglês | MEDLINE | ID: mdl-38695237

RESUMO

AIMS: This study aimed to explore the change trend and group heterogeneity of psychosocial adjustment level and to determine its influencing factors among young and middle-aged patients with first-episode acute myocardial infarction (AMI). METHODS AND RESULTS: The Psychosocial Adjustment Scale of Illness was used to assess the psychosocial adjustment level of the patients at 1, 3, and 6 months after discharge, respectively. Data were analyzed using Pearson correlation analysis, generalized estimating equations, and growth mixed models. A total of 233 patients were included, and their psychosocial adjustment scores at the three-time points were 57.18 ± 15.50, 36.17 ± 15.02, and 24.22 ± 12.98, respectively. The trajectories of changes in patients' psychosocial adjustment levels were divided into three latent categories: moderate adjustment improvement group (72.5%), low adjustment improvement group (16.3%), and persistent maladjustment group (11.2%). Among them, predictors of the persistent maladjustment group included no spouse, low monthly family income per capita, normal body mass index, never smoking, never exercising, combined with hyperlipidemia, low social support, submission coping, and high perceived stress. CONCLUSIONS: The psychosocial adjustment level of young and middle-aged patients with first-episode AMI showed an upward trend within 6 months after discharge, and there was group heterogeneity in the change trajectory of psychosocial adjustment level. It is suggested that a multi-center, large-sample longitudinal study should be carried out in the future, and the time of follow-up investigation should be extended to further clarify the change trajectory and influencing factors of psychosocial adjustment of patients with different subtypes, to provide the theoretical basis for formulating targeted intervention programs.

2.
Adv Biol (Weinh) ; 8(5): e2300117, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38379270

RESUMO

The incidence of Hepatocellular carcinoma (HCC) and HCC-related deaths have remarkably increased over the recent decades. It has been reported that ß-catenin activation can be frequently observed in HCC cases. This study identified the integrin-linked kinase-associated phosphatase (ILKAP) as a novel ß-catenin-interacting protein. ILKAP is localized both in the nucleus and cytoplasm and regulates the WNT pathway in different ways. First, it is demonstrated that ILKAP activates the WNT pathway in HCC cells by increasing the protein level of ß-catenin and other proteins associated with the WNT signaling, such as c-Myc and CyclinD1. Next, it is shown that ILKAP promotes the metastasis of HCC both in vitro and in vivo in a zebrafish xenograft model. It is also found that ILKAP dephosphorylates the GSK3ß and CK1, contributing to the reduced ubiquitination of ß-catenin. Furthermore, it is identified that ILKAP functions by mediating binding between TCF4 and ß-catenin to enhance expression of WNT target genes. Taken together, the study demonstrates a critical function of ILKAP in metastasis of HCC, since ILKAP is crucial for the activation of the WNT pathway via stabilization of ß-catenin and increased binding between TCF4 and ß-catenin.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Fosfoproteínas Fosfatases , Via de Sinalização Wnt , beta Catenina , Animais , Humanos , beta Catenina/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Metástase Neoplásica , Fator de Transcrição 4/metabolismo , Fator de Transcrição 4/genética , Via de Sinalização Wnt/fisiologia , Peixe-Zebra , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo
3.
iScience ; 26(8): 107334, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37554435

RESUMO

Hedgehog (Hh) signaling mediated by transcription factor Ci/Gli plays a vital role in embryonic development and adult tissue homeostasis in invertebrates and vertebrates, whose dysregulation leads to many human disorders, including cancer. However, till now, cofactors of Ci/Gli which can affect tumorigenesis are not well known. Here, through genetic screen, we find overexpression of active Ci alone is not sufficient to generate tumor-like eye phenotype in Drosophila, however, its overexpression combined with knockdown of hib causes a striking tumor-like big eye phenotype. Mechanistically, HIB/SPOP inhibits Ci/Gli-mediated tumorigenesis by modulating the RNA polymerase II (RNAPII) components Rpb3/Rpb7 stabilities in E3 ligase dependent manner. In addition, Ci/Gli can promote HIB/SPOP-mediated Rpb7/Rpb3 degradation. Taken together, our results indicate Ci/Gli needs to hook up with suitable RNAPII together to achieve the tumor-like eye phenotype and HIB/SPOP plays dual roles through controlling Ci/Gli and Rpb3/Rpb7 protein stabilities to temper Ci/Gli/RNAPII-mediated tumorigenesis.

4.
Mol Psychiatry ; 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914810

RESUMO

Recent studies based on animal models of various neurological disorders have indicated that mitophagy, a selective autophagy that eliminates damaged and superfluous mitochondria through autophagic degradation, may be involved in various neurological diseases. As an important mechanism of cellular stress response, much less is known about the role of mitophagy in stress-related mood disorders. Here, we found that tumor necrosis factor-α (TNF-α), an inflammation cytokine that plays a particular role in stress responses, impaired the mitophagy in the medial prefrontal cortex (mPFC) via triggering degradation of an outer mitochondrial membrane protein, NIP3-like protein X (NIX). The deficits in the NIX-mediated mitophagy by TNF-α led to the accumulation of damaged mitochondria, which triggered synaptic defects and behavioral abnormalities. Genetic ablation of NIX in the excitatory neurons of mPFC caused passive coping behaviors to stress, and overexpression of NIX in the mPFC improved TNF-α-induced synaptic and behavioral abnormalities. Notably, ketamine, a rapid on-set and long-lasting antidepressant, reversed the TNF-α-induced behavioral abnormalities through activation of NIX-mediated mitophagy. Furthermore, the downregulation of NIX level was also observed in the blood of major depressive disorder patients and the mPFC tissue of animal models. Infliximab, a clinically used TNF-α antagonist, alleviated both chronic stress- and inflammation-induced behavioral abnormalities via restoring NIX level. Taken together, these results suggest that NIX-mediated mitophagy links inflammation signaling to passive coping behaviors to stress, which underlies the pathophysiology of stress-related emotional disorders.

5.
Asian J Androl ; 25(3): 375-381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36153926

RESUMO

Bisphenol A is a common environmental factor and endocrine disruptor that exerts a negative impact on male reproductive ability. By exploring bisphenol A-induced testicular cell death using the Institute of Cancer Research (ICR) mouse model, we found that a ferroptosis phenomenon may exist. Mice were divided into six groups and administered different doses of bisphenol A via intragastric gavage once daily for 45 consecutive days. Serum was then collected to determine the levels of superoxide dismutase and malondialdehyde. Epididymal sperm was also collected for semen analysis, and testicular tissue was collected for ferritin content determination, electron microscope observation of mitochondrial morphology, immunohistochemistry, real-time quantitative polymerase chain reaction, and western blot analysis. Exposure to bisphenol A was found to decrease sperm quality and cause oxidative damage, iron accumulation, and mitochondrial damage in the testes of mice. In addition, bisphenol A was confirmed to affect the expression of the ferroptosis-related genes, glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), cyclooxygenase 2 (COX2), and acyl-CoA synthetase 4 (ACSL4) in mouse testicular tissues. Accordingly, we speculate that bisphenol A induces oxidative stress, which leads to the ferroptosis of testicular cells. Overall, the inhibition of ferroptosis may be a potential strategy to reduce male reproductive toxicity caused by bisphenol A.


Assuntos
Ferroptose , Testículo , Masculino , Camundongos , Animais , Testículo/metabolismo , Sêmen , Estresse Oxidativo
6.
Front Bioeng Biotechnol ; 11: 1298890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38283167

RESUMO

Objective: Bispecific antibodies (BsAbs) have demonstrated significant therapeutic impacts for the treatment of a broad spectrum of diseases that include oncology, auto-immune, and infectious diseases. However, the large-scale production of clinical batches of bispecific antibodies still has many challenges that include having low yield, poor stability, and laborious downstream purification processes. To address such challenges, we describe the optimization of the controlled Fab arm exchange (cFAE) process for the efficient generation of BsAbs. Methods: The process optimization of a large-scale good manufacturing practice (GMP) cFAE strategy to prepare BsAbs was based on screening the parameters of temperature, reduction, oxidation, and buffer exchange. We include critical quality standards for the reducing agent cysteamine hydrochloride. Results: This large-scale production protocol enabled the generation of bispecific antibodies with >90% exchange yield and at >95% purity. The subsequent downstream processing could use typical mAb procedures. Furthermore, we demonstrated that the bispecific generation protocol can be scaled up to ∼60 L reaction scale using parental monoclonal antibodies that were expressed in a 200 L bioreactor. Conclusion: We presented a robust development strategy for the cFAE process that can be used for a larger scale GMP BsAb production.

7.
Front Surg ; 9: 917458, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784937

RESUMO

Purpose: To explore the changes of blood lipid and serum inflammatory factors in pregnant women with hypertensive disorder complicating pregnancy (HDP) and the relationship with disease development. Methods: 107 pregnant women with HDP who had regular prenatal examination in our hospital from July 2018 to July 2021 were selected as the research objects. According to the severity of the disease, they were divided into gestational hypertension group, mild preeclampsia group and severe preeclampsia group. 30 healthy pregnant women who underwent prenatal examination in the same period were selected as the healthy group. Serum total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), lipoprotein-associated phospholipaseA2 (Lp-PLA2), C- reactive protein (CRP), interleukin -6 (IL-6), tumor necrosis factor-α (TNF-α) were measured. Receiver operating characteristic curve (ROC) was used to analyze the predictive value of blood lipid and serum inflammatory factors in pregnant women with HDP. Results: The levels of serum TC, TG and LDL-C increased with the progression of HDP, the level of serum HDL-C decreased with the progression of HDP (P < 0.05). The levels of serum Lp-PLA2, CRP, IL-6 and TNF-α increased with the progression of HDP (P < 0.05). The AUC of serum TC, TG, HDL-C and LDL-C levels for predicting HDP were 0.759, 0.854, 0.770 and 0.785, respectively. The AUC of serum Lp-PLA2, CRP, IL-6 and TNF-α levels for predicting HDP were 0.873, 0.991, 0.966 and 0.999, respectively. Conclusion: The levels of blood lipid and serum inflammatory factor are closely related to HDP, which has certain value in predicting the occurrence and development of HDP.

8.
Nanomaterials (Basel) ; 12(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35745398

RESUMO

Every year, a large amount of tobacco waste liquid (TWL) is discharged into the environment, resulting in serious pollution for the environment. In this work, a TWL-based particle (OACT) was fabricated by CaO, attapulgite (ATP), and TWL, and, then, OACT was coated by amino silicon oil (ASO) to form OACT@ASO. Therein, OACT@ASO had high controlled-release ability for fulvic acid (FA), because of the nanonetworks structure for ATP and the high content of FA in TWL. The release ratio (RR) of FA from OACT@ASO reached 94% at 75 h in deionized water, and 23% at 32 d in silica sand. Furthermore, the release mechanism of FA from OACT@ASO was consistent with the First-order law. Additionally, OACT@ASO also possessed high immobilization capacity for Cu(II), Cd(II), and Pb(II) (CCP) in soil. Notably, a pot experiment indicated that OACT@ASO could facilitate the growth of pakchoi seedlings and decrease the absorption of CCP by pakchoi seedlings. Thus, this study provides a new kind of organic fertilizer which could not only release FA, but also immobilize CCP in soil.

9.
Exp Gerontol ; 163: 111802, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35398474

RESUMO

BACKGROUND: Age-related chronic inflammatory process is often referred to as "inflammaging", which had been described in several human disorders, including sarcopenia. Recently, mitochondrial DNA (MtDNA) has moved into the spotlight as a "damage-associated molecular pattern" (DAMP) agent that can potentially elicit inflammation. Yet, the roles of this mitochondrial DAMP have never been investigated in sarcopenia. DESIGN: Cross-sectional study. PARTICIPANTS: From January 2021 to June 2021, elderly outpatients ≥65 years and able to finish a comprehensive geriatric assessment were recruited in our study. METHODS: Participants were divided into sarcopenia group and non-sarcopenia group according to the DXA scans and grip strength. Genomic DNA was extracted from plasma and peripheral blood mononuclear cells (PBMCs), and changes in MtDNA copies were quantified using qPCR. Plasma levels of inflammatory cytokines were measured using ELISA kits. Loss of mitochondrial membrane potential (Δψm) in PBMCs was analyzed using the fluorescent probe JC-1. RESULTS: Participants with sarcopenia were significantly older, more likely to be physically inactive, and had higher levels of circulating cell-free MtDNA (ccf-MtDNA) (all p < 0.05). After adjusting for potential confounders, ccf-MtDNA was independently associated with increased odds of sarcopenia (adjusted odds ratio (AOR), 1.576; p = 0.009). Furthermore, ROC curve analysis showed that ccf-MtDNA had an area under the curve (AUC) of 0.726 (95% CI: 0.607-0.844; p < 0.05) for distinguishing elderly subjects from sarcopenia. Compared with non-sarcopenia subjects, plasma interleukin (IL)-6 and IL-8 were significantly higher in sarcopenia subjects (both p < 0.05). By performing a correlation test, it was found that the level of IL-6 was positively correlated with ccf-MtDNA (r = 0.301; p < 0.05). Then, PBMCs were used as surrogates for mitochondria-rich cells, and the results showed that the relative amplification of MtDNA in PBMCs was significantly reduced (p < 0.05), whereas the depolarization of Δψm was significantly increased in sarcopenia subjects (p < 0.05). CONCLUSIONS: Taken together, our data suggested that circulating MtDNA might be a novel and important source of inflammatory stimuli potentially relevant for sarcopenia in elderly people, and this would provide an attractive therapeutic target to improve this disease.


Assuntos
Ácidos Nucleicos Livres , Sarcopenia , Idoso , Ácidos Nucleicos Livres/genética , Estudos Transversais , DNA Mitocondrial/genética , Humanos , Interleucina-6 , Leucócitos Mononucleares , Mitocôndrias/genética
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 649-654, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323045

RESUMO

OBJECTIVE: To establish a nicotine intravenous self-administration rat model, and to examine, with this model, the effects of two flavoring additives, menthol and cineole, on nicotine dependence. METHODS: Thirty male Sprague-Dawley (SD) rats were included in the study. After jugular venous catheterization was performed, fixed concentration of nicotine was administered in order to train the rats and establish the rat model of intravenous self-administration groups, receiving intraperitoneal injection of menthol, cineole, and dimethyl sulfoxide (DMSO), the vehicle that was used for the control group. The rats were tested with different fixed-ratio (FR) schedules, including FR1 schedule, in which the rat received one nicotine infusion for every active nose poke, FR2 schedule, in which the rat received one nicotine infusion for every two active nose pokes, and FR5 schedule, in which the rat received one nicotine infusion for every five active nose pokes. The number of active and inactive poke responses and the number of nicotine infusion were documented accordingly. RESULTS: After 10 days of training in nicotine self-administration, the 30 rats demonstrated significant increase in the number of active poke responses and the number of nicotine infusion, which were maintained at a stable and relatively high level. The number of active poke responses was significantly higher that of inactive poke responses ( P< 0.001). The rat model of intravenous nicotine self-administration was successfully established. In the testing phase, under the FR2 schedule, the menthol group showed a reduced number of active poke responses ( P=0.020). Under the FR5 schedule, the groups showed obvious interaction between time and the number of active poke responses ( P<0.011), with the menthol group showing reduced number of active poke responses on day three ( P=0.011) and the cineole group showing rising number of active poke responses on day three ( P=0.003). The DMSO control group did not show any significant change. CONCLUSIONS: Menthol and cineole are shown to have an effect on nicotine dependence. When there is relative difficulty involved in obtaining nicotine, menthol suppresses nicotine dependence, whereas cineole enhances nicotine dependence.


Assuntos
Mentol , Tabagismo , Animais , Condicionamento Operante , Eucaliptol , Masculino , Ratos , Ratos Sprague-Dawley , Reforço Psicológico , Nicotiana
11.
Nature ; 581(7808): 333-338, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433614

RESUMO

As members of the membrane-bound O-acyltransferase (MBOAT) enzyme family, acyl-coenzyme A:cholesterol acyltransferases (ACATs) catalyse the transfer of an acyl group from acyl-coenzyme A to cholesterol to generate cholesteryl ester, the primary form in which cholesterol is stored in cells and transported in plasma1. ACATs have gained attention as potential drug targets for the treatment of diseases such as atherosclerosis, Alzheimer's disease and cancer2-7. Here we present the cryo-electron microscopy structure of human ACAT1 as a dimer of dimers. Each protomer consists of nine transmembrane segments, which enclose a cytosolic tunnel and a transmembrane tunnel that converge at the predicted catalytic site. Evidence from structure-guided mutational analyses suggests that acyl-coenzyme A enters the active site through the cytosolic tunnel, whereas cholesterol may enter from the side through the transmembrane tunnel. This structural and biochemical characterization helps to rationalize the preference of ACAT1 for unsaturated acyl chains, and provides insight into the catalytic mechanism of enzymes within the MBOAT family8.


Assuntos
Biocatálise , Microscopia Crioeletrônica , Esterol O-Aciltransferase/química , Esterol O-Aciltransferase/metabolismo , Domínio Catalítico , Humanos , Modelos Moleculares , Multimerização Proteica , Esterol O-Aciltransferase/ultraestrutura , Especificidade por Substrato
12.
J Mol Cell Biol ; 11(9): 791-803, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30925584

RESUMO

Hedgehog (Hh) signalling plays conserved roles in controlling embryonic development; its dysregulation causes many diseases including cancers. The G protein-coupled receptor Smoothened (Smo) is the key signal transducer of the Hh pathway, whose posttranslational regulation has been shown to be critical for its accumulation and activation. Ubiquitination has been reported an essential posttranslational regulation of Smo. Here, we identify a novel E3 ligase of Smo, Herc4, which binds to Smo, and regulates Hh signalling by controlling Smo ubiquitination and degradation. Interestingly, our data suggest that Herc4-mediated Smo degradation is regulated by Hh in PKA-primed phosphorylation-dependent and independent manners.


Assuntos
Proteínas de Drosophila/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Receptor Smoothened/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Drosophila , Proteínas de Drosophila/genética , Técnicas de Silenciamento de Genes , Lisossomos/metabolismo , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
13.
Stem Cell Res Ther ; 10(1): 98, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885249

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) are increasingly being applied as a therapy for liver fibrosis. Exosomes possess similar functions to their parent cells; however, they are safe and effective cell-free reagents with controllable and predictable outcomes. In this study, we investigated the therapeutic potential and underlying molecular mechanism for human bone mesenchymal stem cells-derived exosomes (hBM-MSCs-Ex) in the treatment of liver fibrosis. METHODS: We established an 8-week CCl4-induced rat liver fibrosis model, after which, we administered hBM-MSCs-Ex in vivo for 4 weeks. The resulting histopathology, liver function, and inflammatory cytokines were analyzed. In addition, we investigated the anti-fibrotic mechanism of hBM-MSCs-Ex in hepatic stellate cells (HSCs) and liver fibrosis tissue, by western blotting for the expression of Wnt/ß-catenin signaling pathway-related genes. RESULTS: In vivo administration of hBM-MSCs-Ex effectively alleviated liver fibrosis, including a reduction in collagen accumulation, enhanced liver functionality, inhibition of inflammation, and increased hepatocyte regeneration. Moreover, based on measurement of the collagen area, Ishak fibrosis score, MDA levels, IL-1, and IL-6, the therapeutic effect of hBM-MSCs-Ex against liver fibrosis was significantly greater than that of hBM-MSCs. In addition, we found that hBM-MSCs-Ex inhibited the expression of Wnt/ß-catenin pathway components (PPARγ, Wnt3a, Wnt10b, ß-catenin, WISP1, Cyclin D1), α-SMA, and Collagen I, in both HSCs and liver fibrosis tissue. CONCLUSIONS: These results suggest that hBM-MSCs-Ex treatment could ameliorate CCl4-induced liver fibrosis via inhibition of HSC activation through the Wnt/ß-catenin pathway.


Assuntos
Células da Medula Óssea/metabolismo , Intoxicação por Tetracloreto de Carbono , Exossomos , Cirrose Hepática , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt , Animais , Células da Medula Óssea/patologia , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Intoxicação por Tetracloreto de Carbono/terapia , Exossomos/metabolismo , Exossomos/patologia , Exossomos/transplante , Feminino , Xenoenxertos , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Células-Tronco Mesenquimais/patologia , Ratos , Ratos Sprague-Dawley , beta Catenina
14.
J Mol Cell Biol ; 10(3): 243-257, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992318

RESUMO

The Hedgehog (Hh) signaling pathway plays important roles in developmental processes including pattern formation and tissue homeostasis. The seven-pass transmembrane receptor Smoothened (Smo) is the pivotal transducer in the pathway; it, and thus the pathway overall, is regulated by ubiquitin-mediated degradation, which occurs in the absence of Hh. In the presence of Hh, the ubiquitination levels of Smo are decreased, but the molecular basis for this outcome is not well understood. Here, we identify the deubiquitinase UCHL5 as a positive regulator of the Hh pathway. We provide both genetic and biochemical evidence that UCHL5 interacts with and deubiquitinates Smo, increasing stability and promoting accumulation at the cell membrane. Strikingly, we find that Hh enhances the interaction between UCHL5 and Smo, thereby stabilizing Smo. We also find that proteasome subunit RPN13, an activator of UCHL5, could enhance the effect of UCHL5 on Smo protein level. More importantly, we find that the mammalian counterpart of UCHL5, UCH37, plays the same role in the regulation of Hh signaling by modulating hSmo ubiquitination and stability. Our findings thus identify UCHL5/UCH37 as a critical regulator of Hh signaling and potential therapeutic target for cancers.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Receptor Smoothened/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Técnicas de Silenciamento de Genes , Ligação Proteica , Estabilidade Proteica , Ubiquitina Tiolesterase/genética , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação
15.
Sci Rep ; 7(1): 2891, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28588207

RESUMO

Hedgehog (Hh) signaling plays a pivotal role in animal development and its deregulation in humans causes birth defects and several types of cancer. Protein Kinase A (PKA) modulates Hh signaling activity through phosphorylating the transcription factor Cubitus interruptus (Ci) and G protein coupled receptor (GPCR) family protein Smoothened (Smo) in Drosophila, but how PKA activity is regulated remains elusive. Here, we identify a novel regulator of the Hh pathway, the capping-enzyme mRNA-cap, which positively regulates Hh signaling activity through modulating PKA activity. We provide genetic and biochemical evidence that mRNA-cap inhibits PKA kinase activity to promote Hh signaling. Interestingly, regulation of Hh signaling by mRNA-cap depends on its cytoplasmic capping-enzyme activity. In addition, we show that the mammalian homolog of mRNA-cap, RNGTT, can replace mRNA-cap to play the same function in the Drosophila Hh pathway and that knockdown of Rngtt in cultured mammalian cells compromised Shh pathway activity, suggesting that RNGTT is functionally conserved. Our study makes an unexpected link between the mRNA capping machinery and the Hh signaling pathway, unveils a new facet of Hh signaling regulation, and reveals a potential drug target for modulating Hh signaling activity.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Hedgehog/metabolismo , Nucleotidiltransferases/metabolismo , Capuzes de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Modelos Biológicos , Fenótipo , Asas de Animais
16.
Environ Toxicol ; 32(2): 530-540, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27045816

RESUMO

AIMS: It has been proven that carbon nanoparticles or diesel exhaust particles stimulate platelet activation. However, the effect of fine particle matter (PM2.5 ) on platelet activation remains unknown, which motivates this study. METHODS: PM2.5 samples were collected in an urban area of Zhengzhou, China. To study the morphological characteristics and the mass concentrations of trace elements of PM2.5 samples, a filed-emission scanning electron microscope, the Image-J software, and an inductively coupled plasma mass spectrometry were used. Washed human platelets or platelet-rich-plasma were used to study the effect of PM2.5 on platelet aggregation, P-selectin expression, or platelet signaling pathways. The cytotoxicity in platelets exposed to PM2.5 was evaluated by a lactate dehydrogenase assay kit. In addition, platelet adhesion and spreading were studied on collagen-coated surfaces in stable conditions. RESULTS: The filed-emission scanning electron microscope scanning showed that PM2.5 samples varied in shape and size distributions. The mean equivalent spherical diameter of these particles was 1.97 ± 0.04 µm, of which 82.40% were particles with equivalent spherical diameters of less than 2.5 µm. The mass concentration of Ca was higher than that of other elements. The other elements followed the trend of Al>Fe>Zn>Mg>Pb>K>Mn>Cu>Ti>Ba>As>Sr>Sn>Sb>Cd>B>Se>Mo>Ag>Ni>TI>V>Co. Furthermore, pretreatment of PM2.5 significantly inhibited rather than potentiated collagen-induced platelet aggregation and P-selectin expression, whereas it had no significant effect on ADP-induced platelet aggregation and P-selectin expression. The lactate dehydrogenase analysis showed trivial cytotoxic effect of PM2.5 exposure on platelets. Pretreatment of PM2.5 inhibited platelet adhesion on immobilized collagen-coated surfaces; however, it almost did not impact the platelet spreading. Immunoblotting analysis indicated that PM2.5 reduced collagen-induced phosphorylation of phospholipase C gamma-2 (PLCγ2) at Tyr759, Akt at Ser473, and glycogen synthase kinase 3ß (GSK3ß) at Ser9. CONCLUSIONS: PM2.5 attenuated collagen-induced platelet aggregation, α-granule secretion and adhesion, with the potential mechanism of impairing PLCγ2, Akt, and GSK3ß signaling. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 530-540, 2017.


Assuntos
Poluentes Atmosféricos/toxicidade , Colágeno/farmacologia , Material Particulado/toxicidade , Ativação Plaquetária/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adulto , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , China , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Selectina-P/metabolismo , Fosfolipase C gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Oligoelementos/análise , Adulto Jovem
17.
Onco Targets Ther ; 9: 2759-67, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27274272

RESUMO

BACKGROUND: Inflammation has been reported to be involved in carcinogenesis and cancer progression. This study was designed to explore the prognostic significance of lymphocyte-to-monocyte ratio (LMR) and serum C-reactive protein (CRP) in nonmetastatic clear cell renal cell carcinoma (ccRCC) patients after treatment. METHODS: The retrospective study consisted of 985 patients with ccRCC who had undergone nephrectomy from 2005 to 2010 at multiple centers. The patients were divided into four groups using a quartile of LMR or CRP, and their associations with clinical characteristics and outcome were systematically estimated. RESULTS: Both low LMR and high CRP significantly diminished overall survival (OS) and metastasis-free survival (MFS) in patients with ccRCC. Further investigation indicated that LMR and CRP were independent prognostic factors of both OS and MFS. Integration of LMR and CRP into a predictive model, including significant variables in multivariate analysis, established a nomogram to predict accurately the 3- and 5-year survival for nonmetastatic patients with ccRCC. CONCLUSION: LMR and CRP represent independent prognostic factors of OS and MFS for patients with ccRCC. Incorporation of LMR and CRP into the traditional TNM staging system may improve their predictive performance.

18.
Dev Cell ; 34(1): 58-72, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26120032

RESUMO

Hedgehog (Hh) signaling plays essential roles in animal development and tissue homeostasis, and its misregulation causes congenital diseases and cancers. Regulation of the ubiquitin/proteasome-mediated proteolysis of Ci/Gli transcription factors is central to Hh signaling, but whether deubiquitinase is involved in this process remains unknown. Here, we show that Hh stimulates the binding of a ubiquitin-specific protease Usp7 to Ci, which positively regulates Hh signaling activity through inhibiting Ci ubiquitination and degradation mediated by both Slimb-Cul1 and Hib-Cul3 E3 ligases. Furthermore, we find that Usp7 forms a complex with GMP-synthetase (GMPS) to promote Hh pathway activity. Finally, we show that the mammalian counterpart of Usp7, HAUSP, positively regulates Hh signaling by modulating Gli ubiquitination and stability. Our findings reveal a conserved mechanism by which Ci/Gli is stabilized by a deubiquitination enzyme and identify Usp7/HUASP as a critical regulator of Hh signaling and potential therapeutic target for Hh-related cancers.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Ubiquitinação/fisiologia , Animais , Processamento de Proteína Pós-Traducional/fisiologia , Ubiquitina/metabolismo
19.
Cell Res ; 24(5): 595-609, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24603360

RESUMO

Hedgehog (Hh) signaling plays vital roles in animal development and tissue homeostasis, and its misregulation causes congenital diseases and several types of cancer. Suppressor of Fused (Su(fu)) is a conserved inhibitory component of the Hh signaling pathway, but how it is regulated remains poorly understood. Here we demonstrate that in Drosophila Hh signaling promotes downregulation of Su(fu) through its target protein HIB (Hh-induced BTB protein). Interestingly, although HIB-mediated downregulation of Su(fu) depends on the E3 ubiquitin ligase Cul3, HIB does not directly regulate Su(fu) protein stability. Through an RNAi-based candidate gene screen, we identify the spliceosome factor Crooked neck (Crn) as a regulator of Su(fu) level. Epistasis analysis indicates that HIB downregulates Su(fu) through Crn. Furthermore, we provide evidence that HIB retains Crn in the nucleus, leading to reduced Su(fu) protein level. Finally, we show that SPOP, the mammalian homologue of HIB, can substitute HIB to downregulate Su(fu) level in Drosophila. Our study suggests that Hh regulates both Ci and Su(fu) levels through its target HIB, thus uncovering a novel feedback mechanism that regulates Hh signal transduction. The dual function of HIB may provide a buffering mechanism to fine-tune Hh pathway activity.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Proteínas Hedgehog/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Linhagem Celular , Proteínas Culina/metabolismo , Regulação para Baixo , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas Repressoras/genética , Transdução de Sinais
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