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1.
J Cell Biol ; 221(1)2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34813648

RESUMO

Primary cilia transduce diverse signals in embryonic development and adult tissues. Defective ciliogenesis results in a series of human disorders collectively known as ciliopathies. The CP110-CEP97 complex removal from the mother centriole is an early critical step for ciliogenesis, but the underlying mechanism for this step remains largely obscure. Here, we reveal that the linear ubiquitin chain assembly complex (LUBAC) plays an essential role in ciliogenesis by targeting the CP110-CEP97 complex. LUBAC specifically generates linear ubiquitin chains on CP110, which is required for CP110 removal from the mother centriole in ciliogenesis. We further identify that a pre-mRNA splicing factor, PRPF8, at the distal end of the mother centriole acts as the receptor of the linear ubiquitin chains to facilitate CP110 removal at the initial stage of ciliogenesis. Thus, our study reveals a direct mechanism of regulating CP110 removal in ciliogenesis and implicates the E3 ligase LUBAC as a potential therapy target of cilia-associated diseases, including ciliopathies and cancers.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centríolos/metabolismo , Cílios/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Organogênese , Fosfoproteínas/metabolismo , Ubiquitina/metabolismo , Animais , Linhagem Celular , Humanos , Camundongos , Complexos Multiproteicos , Proteínas de Ligação a RNA/metabolismo , Especificidade por Substrato , Ubiquitinação , Peixe-Zebra
2.
Neurobiol Pain ; 10: 100077, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34841128

RESUMO

Childhood acute lymphoblastic leukemia (ALL) is a significant clinical problem that can be effectively treated with vincristine, a vinca alkaloid-based chemotherapeutic agent. However, nearly all children receiving vincristine treatment develop vincristine-induced peripheral neuropathy (VIPN). The impact of adolescent vincristine treatment across the lifespan remains poorly understood. We, consequently, developed an adolescent rodent model of VIPN which can be utilized to study possible long term consequences of vincristine treatment in the developing rat. We also evaluated the therapeutic efficacy of voluntary exercise and potential impact of obesity as a genetic risk factor in this model on the development and maintenance of VIPN. Out of all the dosing regimens we evaluated, the most potent VIPN was produced by fifteen consecutive daily intraperitoneal (i.p.) vincristine injections at 100 µg/kg/day, throughout the critical period of adolescence from postnatal day 35 to 49. With this treatment, vincristine-treated animals developed hypersensitivity to mechanical and cold stimulation of the plantar hind paw surface, which outlasted the period of vincristine treatment and resolved within two weeks following the cessation of vincristine injection. By contrast, impairment in grip strength gain was delayed by vincristine treatment, emerging shortly following the termination of vincristine dosing, and persisted into early adulthood without diminishing. Interestingly, voluntary wheel running exercise prevented the development of vincristine-induced hypersensitivities to mechanical and cold stimulation. However, Zucker fa/fa obese animals did not exhibit higher risk of developing VIPN compared to lean rats. Our studies identify sensory and motor impairments produced by vincristine in adolescent animals and support the therapeutic efficacy of voluntary exercise for suppressing VIPN in developing rats.

3.
EMBO Rep ; : e53166, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34779554

RESUMO

Cyclic GMP-AMP synthase (cGAS) functions as a key sensor for microbial invasion and cellular damage by detecting emerging cytosolic DNA. Here, we report that GTPase-activating protein-(SH3 domain)-binding protein 1 (G3BP1) primes cGAS for its prompt activation by engaging cGAS in a primary liquid-phase condensation state. Using high-resolution microscopy, we show that in resting cells, cGAS exhibits particle-like morphological characteristics, which are markedly weakened when G3BP1 is deleted. Upon DNA challenge, the pre-condensed cGAS undergoes liquid-liquid phase separation (LLPS) more efficiently. Importantly, G3BP1 deficiency or its inhibition dramatically diminishes DNA-induced LLPS and the subsequent activation of cGAS. Interestingly, RNA, previously reported to form condensates with cGAS, does not activate cGAS. Accordingly, we find that DNA - but not RNA - treatment leads to the dissociation of G3BP1 from cGAS. Taken together, our study shows that the primary condensation state of cGAS is critical for its rapid response to DNA.

6.
J Immunol ; 206(10): 2453-2467, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33941659

RESUMO

The detection of intracellular nucleic acids is a fundamental mechanism of host defense against infections. The dysregulated nucleic acid sensing, however, is a major cause for a number of autoimmune diseases. In this study, we report that GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) is critical for both intracellular DNA- and RNA-induced immune responses. We found that in both human and mouse cells, the deletion of G3BP1 led to the dampened cGAS activation by DNA and the insufficient binding of RNA by RIG-I. We further found that resveratrol (RSVL), a natural compound found in grape skin, suppressed both intracellular DNA- and RNA-induced type I IFN production through inhibiting G3BP1. Importantly, using experimental mouse models for Aicardi-Goutières syndrome, an autoimmune disorder found in humans, we demonstrated that RSVL effectively alleviated intracellular nucleic acid-stimulated autoimmune responses. Thus, our study demonstrated a broader role of G3BP1 in sensing different kinds of intracellular nucleic acids and presented RSVL as a potential treatment for autoimmune conditions caused by dysregulated nucleic acid sensing.


Assuntos
Autoimunidade/genética , DNA Helicases/deficiência , DNA Helicases/metabolismo , Espaço Intracelular/metabolismo , Ácidos Nucleicos/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/deficiência , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/deficiência , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/deficiência , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Transdução de Sinais/genética , Células A549 , Animais , Autoimunidade/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA Helicases/antagonistas & inibidores , DNA Helicases/genética , Fibroblastos/metabolismo , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Espaço Intracelular/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/genética , RNA Helicases/antagonistas & inibidores , RNA Helicases/genética , Proteínas com Motivo de Reconhecimento de RNA/antagonistas & inibidores , Proteínas com Motivo de Reconhecimento de RNA/genética , Resveratrol/administração & dosagem , Transdução de Sinais/imunologia , Transfecção
7.
Nephron ; 145(5): 540-552, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33975327

RESUMO

BACKGROUND: In recent years, increasing discovery of the extremely important regulatory effects of circular RNAs on biological development, angiogenesis, tumor genesis, and development, as well as stem cell proliferation and differentiation has provided new opportunities for investigating regulation mechanism in angiogenesis. OBJECTIVES: This study explored the expression of circ 001839 in renal ischemia-reperfusion injury (RI-RI) rats and whether its upstream microRNA-432-3p (miR-432-3p) affects inflammation in both RI-RI rats and NRK52E cells. METHODS: Rat model of RI-RI was made, and circ 001839 was identified by the gene-chip analysis in RI-RI rats. Expression of circ 001839 and miR-432-3p was measured by reverse transcription-quantitative polymerase chain reaction, protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, interferon (IFN)-γ, IL-6, and IL-18 in rat serum and cell supernatant was determined by ELISA, and the expression of NOD-like receptor 3 (NLRP3) and other gap-associated proteins in NRK52E cells was evaluated by Western blot analysis. Next, to verify the regulatory relationship between circ 001839 and miR-432-3p, 2 luciferase reporters were constructed. RESULTS: Circ 001839 expression of RI-RI rats and NRK52E cells was significantly upregulated, compared with the control group. Circ 001839 overexpression significantly increased inflammation through promoting TNF-α, IFN-γ, and IL-6 expression levels in NRK52E cells. Overexpression of miR-432-3p significantly promoted inflammation in NRK52E cells via induction of NLRP3. Moreover, miR-432-3p decreased the effects of circ 001839-induced inflammation in NRK52E cells. CONCLUSIONS: These findings suggested that circ 001839 promoted inflammation in RI-RI through NLRP3 by miR-432-3p.

8.
J Transl Med ; 19(1): 220, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030718

RESUMO

BACKGROUND: The phytocannabinoid cannabidiol (CBD) exhibits anxiolytic activity and has been promoted as a potential treatment for post-traumatic stress disorders. How does CBD interact with the brain to alter behavior? We hypothesized that CBD would produce a dose-dependent reduction in brain activity and functional coupling in neural circuitry associated with fear and defense. METHODS: During the scanning session awake mice were given vehicle or CBD (3, 10, or 30 mg/kg I.P.) and imaged for 10 min post treatment. Mice were also treated with the 10 mg/kg dose of CBD and imaged 1 h later for resting state BOLD functional connectivity (rsFC). Imaging data were registered to a 3D MRI mouse atlas providing site-specific information on 138 different brain areas. Blood samples were collected for CBD measurements. RESULTS: CBD produced a dose-dependent polarization of activation along the rostral-caudal axis of the brain. The olfactory bulb and prefrontal cortex showed an increase in positive BOLD whereas the brainstem and cerebellum showed a decrease in BOLD signal. This negative BOLD affected many areas connected to the ascending reticular activating system (ARAS). The ARAS was decoupled to much of the brain but was hyperconnected to the olfactory system and prefrontal cortex. CONCLUSION: The CBD-induced decrease in ARAS activity is consistent with an emerging literature suggesting that CBD reduces autonomic arousal under conditions of emotional and physical stress.


Assuntos
Canabidiol , Animais , Encéfalo , Canabidiol/farmacologia , Medo , Imageamento por Ressonância Magnética , Camundongos , Vigília
9.
Nat Commun ; 12(1): 2114, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837182

RESUMO

Lack of detailed knowledge of SARS-CoV-2 infection has been hampering the development of treatments for coronavirus disease 2019 (COVID-19). Here, we report that RNA triggers the liquid-liquid phase separation (LLPS) of the SARS-CoV-2 nucleocapsid protein, N. By analyzing all 29 proteins of SARS-CoV-2, we find that only N is predicted as an LLPS protein. We further confirm the LLPS of N during SARS-CoV-2 infection. Among the 100,849 genome variants of SARS-CoV-2 in the GISAID database, we identify that ~37% (36,941) of the genomes contain a specific trio-nucleotide polymorphism (GGG-to-AAC) in the coding sequence of N, which leads to the amino acid substitutions, R203K/G204R. Interestingly, NR203K/G204R exhibits a higher propensity to undergo LLPS and a greater effect on IFN inhibition. By screening the chemicals known to interfere with N-RNA binding in other viruses, we find that (-)-gallocatechin gallate (GCG), a polyphenol from green tea, disrupts the LLPS of N and inhibits SARS-CoV-2 replication. Thus, our study reveals that targeting N-RNA condensation with GCG could be a potential treatment for COVID-19.


Assuntos
Substituição de Aminoácidos/efeitos dos fármacos , COVID-19/prevenção & controle , Catequina/análogos & derivados , Proteínas do Nucleocapsídeo/genética , SARS-CoV-2/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , COVID-19/virologia , Catequina/farmacologia , Genoma Viral/genética , Humanos , Extração Líquido-Líquido , Proteínas do Nucleocapsídeo/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , SARS-CoV-2/genética , Replicação Viral/genética
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(1): 142-148, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33474904

RESUMO

Objective: To explore the clinical diagnostic application of invasive cardiopulmonary exercise test (iCPET) in patients with unexplained dyspnea. Methods: A retrospective analysis was conducted, covering patients with a chief complaint of exertional dyspnea between May 5, 2017 and October 1, 2020. Right cardiac catheterization examination was performed on patients whose cause had not been identified through routine examination, and further iCPET was performed on patients if no clear etiology was identified through right cardiac catheterization. According to the results and the diagnostic criteria of iCPET, patients showing no obvious abnormalities in the right cardiac catheterization examination were divided into four subgroups: exercise-induced pulmonary arterial hypertension (eiPAH), exercise-induced heart failure with preserved ejection fraction (eiHFpEF), preload failure, and oxidative myopathy. By comparing the lab test, echocardiography, right heart catheter and iCPET peak exercise data of the subgroups, the disease distribution and exercise hemodynamic characteristics of patients with unexplained dyspnea examined by iCPET were described. Results: Of the 1 046 patients with exertional dyspnea, 771 were diagnosed with routine examination, while among the remaining 275 patients, 131 (47.6%) were diagnosed with right cardiac catheterization and 144 (52.4%) showed no clear etiology after routine examination and right cardiac catheterization. Of these 144 patients, 49 (34.0%) received iCPET with a median exercise time of 375 s. A total of 47 patients completed the examination, with a male-to-female ratio of 0.27∶1 and an average age of (47.9±14.4) years old. Among the 47 patients, 76.6% (36/47) aged between 20 and 59 and 78.7% (36/47) lived in urban areas. The preload failure group ( n=27) showed low right atrium pressure at peak exercise intensity. The eiHFpEF group ( n=9) showed high wedge pressure of pulmonary capillaries at peak of exercise intensity. The eiPAH group ( n=8) showed high average pulmonary artery pressure at peak exercise intensity. The oxidative myopathy group ( n=3) was characterized by impairment of tissue uptake and/or utilization of oxygen during exercise. According to the comparison among the three subgroups of the preload failure, eiHFpEF and eiPAH, the eiPAH group had the highest blood K + level in routine examination, while the preload failure group had the lowest blood K + level ( P=0.014). The iCPET of the three subgroups showed statistically significant ( P=0.001) difference in right atrial pressure increase during exercise. Among the three, the eiHFpEF group had the highest increase and the preload failure group had the lowest increase. Conclusion  In unexplained dyspnea patients showing no abnormal results in right cardiac catheterization examination, the main cause was preload failure, which manifested as low right atrial pressure at peak exercise intensity. The study showed that iCPET was of important value for dyspnea cases when the cause of the condition was not revealed with right cardiac catheterization.


Assuntos
Teste de Esforço , Insuficiência Cardíaca , Adulto , Cateterismo Cardíaco , Dispneia/etiologia , Tolerância ao Exercício , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Propulsora Pulmonar , Estudos Retrospectivos
11.
J Cell Biol ; 220(2)2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33475699

RESUMO

Primary cilia protrude from the cell surface and have diverse roles during development and disease, which depends on the precise timing and control of cilia assembly and disassembly. Inactivation of assembly often causes cilia defects and underlies ciliopathy, while diseases caused by dysfunction in disassembly remain largely unknown. Here, we demonstrate that CEP55 functions as a cilia disassembly regulator to participate in ciliopathy. Cep55-/- mice display clinical manifestations of Meckel-Gruber syndrome, including perinatal death, polycystic kidneys, and abnormalities in the CNS. Interestingly, Cep55-/- mice exhibit an abnormal elongation of cilia on these tissues. Mechanistically, CEP55 promotes cilia disassembly by interacting with and stabilizing Aurora A kinase, which is achieved through facilitating the chaperonin CCT complex to Aurora A. In addition, CEP55 mutation in Meckel-Gruber syndrome causes the failure of cilia disassembly. Thus, our study establishes a cilia disassembly role for CEP55 in vivo, coupling defects in cilia disassembly to ciliopathy and further suggesting that proper cilia dynamics are critical for mammalian development.


Assuntos
Aurora Quinase A/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cílios/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Proteínas de Ciclo Celular/deficiência , Células Cultivadas , Centrossomo/metabolismo , Centrossomo/ultraestrutura , Chaperonina com TCP-1/metabolismo , Cílios/ultraestrutura , Transtornos da Motilidade Ciliar/patologia , Encefalocele/patologia , Estabilidade Enzimática , Marcação de Genes , Células HEK293 , Humanos , Camundongos , Mitose , Fenótipo , Doenças Renais Policísticas/patologia , Ligação Proteica , Retinite Pigmentosa/patologia , Receptor Smoothened/metabolismo
12.
Nat Commun ; 12(1): 662, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510165

RESUMO

Dynamic assembly and disassembly of primary cilia controls embryonic development and tissue homeostasis. Dysregulation of ciliogenesis causes human developmental diseases termed ciliopathies. Cell-intrinsic regulatory mechanisms of cilia disassembly have been well-studied. The extracellular cues controlling cilia disassembly remain elusive, however. Here, we show that lysophosphatidic acid (LPA), a multifunctional bioactive phospholipid, acts as a physiological extracellular factor to initiate cilia disassembly and promote neurogenesis. Through systematic analysis of serum components, we identify a small molecular-LPA as the major driver of cilia disassembly. Genetic inactivation and pharmacological inhibition of LPA receptor 1 (LPAR1) abrogate cilia disassembly triggered by serum. The LPA-LPAR-G-protein pathway promotes the transcription and phosphorylation of cilia disassembly factors-Aurora A, through activating the transcription coactivators YAP/TAZ and calcium/CaM pathway, respectively. Deletion of Lpar1 in mice causes abnormally elongated cilia and decreased proliferation in neural progenitor cells, thereby resulting in defective neurogenesis. Collectively, our findings establish LPA as a physiological initiator of cilia disassembly and suggest targeting the metabolism of LPA and the LPA pathway as potential therapies for diseases with dysfunctional ciliogenesis.


Assuntos
Cílios/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Neurogênese/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Transdução de Sinais , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cílios/genética , Cílios/metabolismo , Células HEK293 , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Humanos , Lisofosfolipídeos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Ligação Proteica , Interferência de RNA , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo
13.
J Biochem Mol Toxicol ; 34(1): e22419, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31702098

RESUMO

Ionic liquids (ILs) as green alternatives for volatile organic solvents are increasingly used in commercial applications. It is necessary to explore the cytotoxic mechanism of ILs to reduce the risk to human health. For this purpose, cell viability, apoptosis, cytochrome P450 3A4 (CYP3A4), glucose transporter type 2 (GLUT2), and microRNA-122 (miR-122) gene expression in HepG2 cells was evaluated after IL exposure. The results showed that ILs reduced the viability of HepG2 cells through apoptotic cell death. Moreover, ILs markedly upregulated the transcription and protein levels of CYP3A4, but did not affect the expression of GLUT2 in either messenger RNA level or protein level. Finally, ILs increased the expression of miR-122 and inhibition of miR-122 with miR-122 inhibitor blocked ILs-induced apoptosis in HepG2 cells. This finding may contribute to an increased understanding of the in vitro molecular toxicity mechanism of ILs to further understand IL-related human health risks.


Assuntos
Apoptose/efeitos dos fármacos , Brometos/farmacologia , Citocromo P-450 CYP3A/metabolismo , Imidazóis/farmacologia , MicroRNAs/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Células Hep G2 , Humanos
14.
Biomed Pharmacother ; 121: 109669, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31766100

RESUMO

Oxidative stress is closely associated to the onset and progression of many human diseases. Activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway using naturally-derived molecules is an efficient strategy for alleviating the intracellular oxidative insults, and thus blocking the pathogenesis of oxidative stress-induced diseases. In the present study, a naturally-derived isopimarane-type diterpenoid sphaeropsidin C (SC) was identified to be an activator of Nrf2/ARE signaling pathway. Our data indicated that SC was able to stimulate Nrf2-mediated defensive system through promoting Nrf2 translocation, inhibiting Nrf2 ubiquitination, and enhancing Nrf2 stability in normal human lung epithelial Beas-2B cells. Furthermore, SC-induced Nrf2 activation required the involvement of protein kinases, exemplified by protein kinase C (PKC), protein kinase R-like endoplasmic reticulum kinase (PERK), and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K). It alleviated sodium arsenite [As(III)]-induced intracellular oxidative stress in an Nrf2-dependent manner. These results suggested that SC displayed potential application for the prevention and therapy against oxidative stress-induced diseases. Moreover, isopimarane-type diterpenoid represents a promising skeleton for developing Nrf2 activators.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Diterpenos/farmacologia , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Arsenitos/farmacologia , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Humanos , Pulmão/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Compostos de Sódio/farmacologia
15.
J Cell Biol ; 218(12): 4030-4041, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31619485

RESUMO

The primary cilium is a sensory organelle that protrudes from the cell surface. Primary cilia undergo dynamic transitions between assembly and disassembly to exert their function in cell signaling. In this study, we identify the small GTPase Rab7 as a novel regulator of cilia disassembly. Depletion of Rab7 potently induced spontaneous ciliogenesis in proliferating cells and promoted cilia elongation during quiescence. Moreover, Rab7 performs an essential role in cilia disassembly; knockdown of Rab7 blocked serum-induced ciliary resorption, and active Rab7 was required for this process. Further, we demonstrate that Rab7 depletion significantly suppresses cilia tip excision, referred to as cilia ectocytosis, which has been identified as required for cilia disassembly. Mechanically, the failure of F-actin polymerization at the site of excision of cilia tips caused suppression of cilia ectocytosis on Rab7 depletion. Overall, our results suggest a novel function for Rab7 in regulating cilia ectocytosis and cilia disassembly via control of intraciliary F-actin polymerization.


Assuntos
Citoesqueleto de Actina/metabolismo , Cílios/metabolismo , Transdução de Sinais , Proteínas rab de Ligação ao GTP/metabolismo , Actinas/metabolismo , Divisão Celular , Linhagem Celular , Proliferação de Células , GTP Fosfo-Hidrolases/metabolismo , Células HEK293 , Humanos , Proteínas Ligantes de Maltose/metabolismo , Polímeros/metabolismo , RNA Interferente Pequeno/metabolismo
16.
Biochem Biophys Res Commun ; 518(3): 526-532, 2019 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-31445708

RESUMO

Oxidative stress is one of the main pathogenesis for many human diseases. Nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway plays a key role in regulating intracellular antioxidant responses, and thus activation of Nrf2/ARE signaling pathway is a potential chemopreventive or therapeutic strategy to treat diseases caused by oxidative damage. In the present study, we have found that treatment of Beas-2B cells with botrysphins D (BD) attenuated sodium arsenite [As (III)]-induced cell death and apoptosis. Meanwhile, BD was able to upregulate protein levels of Nrf2 and its downstream genes NQO1 and γ-GCS through inducing Nrf2 nuclear translocation, enhancing protein stability, and inhibiting ubiquitination. It was also found that BD-induced activation of the Nrf2/ARE pathway was regulated by PI3K, MEK1/2, PKC, and PERK kinases. Collectively, BD is a novel activator of Nrf2/ARE pathway, and is verified to be a potential preventive agent against oxidative stress-induced damage in human lung tissues.


Assuntos
Antioxidantes/farmacologia , Arsenitos/toxicidade , Diterpenos/farmacologia , Células Epiteliais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Compostos de Sódio/toxicidade , Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/química , Arsênio/toxicidade , Ascomicetos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Diterpenos/química , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Cell Rep ; 28(9): 2386-2396.e5, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461653

RESUMO

It is known that lethal viruses profoundly manipulate host metabolism, but how the metabolism alternation affects the immediate host antiviral immunity remains elusive. Here, we report that the O-GlcNAcylation of mitochondrial antiviral-signaling protein (MAVS), a key mediator of interferon signaling, is a critical regulation to activate the host innate immunity against RNA viruses. We show that O-GlcNAcylation depletion in myeloid cells renders the host more susceptible to virus infection both in vitro and in vivo. Mechanistically, we demonstrate that MAVS O-GlcNAcylation is required for virus-induced MAVS K63-linked ubiquitination, thereby facilitating IRF3 activation and IFNß production. We further demonstrate that D-glucosamine, a commonly used dietary supplement, effectively protects mice against a range of lethal RNA viruses, including human influenza virus. Our study highlights a critical role of O-GlcNAcylation in regulating host antiviral immunity and validates D-glucosamine as a potential therapeutic for virus infections.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Imunidade Inata , Infecções por Orthomyxoviridae/imunologia , Processamento de Proteína Pós-Traducional , Acetilação , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Chlorocebus aethiops , Feminino , Glucosamina/metabolismo , Células HEK293 , Células HeLa , Humanos , Interferon beta/genética , Interferon beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Células Mieloides/metabolismo , Células Mieloides/virologia , Transdução de Sinais , Células Vero
18.
Free Radic Biol Med ; 141: 21-33, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31167117

RESUMO

Oxidative stress is involved in the onset and progression of many human diseases. Activators of the Keap1/Nrf2/ARE pathway effectively inhibit the progression of oxidative stress-induced diseases. Herein, a small library of diterpenoids was established by means of phytochemical isolation, and chemical modification on naturally occurring molecules. The diterpenoids were subjected to a NAD(P)H: quinone reductase (QR) assay to evaluate its potential inhibition against oxidative stress. Sixteen diterpenoids were found to be novel potential activators of Nrf2-mediated defensive response. Of which, an isopimarane-type diterpenoid, sphaeropsidin A (SA), was identified as a potent activator of the Keap1/Nrf2/ARE pathway, and displayed approximately 5-folds potency than that of sulforaphane (SF). SA activated Nrf2 and its downstream cytoprotective genes through enhancing the stabilization of Nrf2 in a process involving PI3K, PKC, and PERK, as well as potentially interrupting Nrf2-Keap1 protein-protein interaction. In addition, SA conferred protection against sodium arsenite [As(III)]- and cigarette smoke extract (CSE)-induced redox imbalance and cytotoxicity in human lung epithelial cells, as wells as inhibited metronidazole (MTZ)-induced oxidative insult in Tg (krt4: NTR-hKikGR)cy17 transgenic zebrafish and lipopolysaccharide (LPS)-induced oxidative damage in wild-type AB zebrafish. These results imply that SA is a lead compound for therapeutic agent against oxidative stress-induced diseases, and diterpenoid is a good resource for discovering drug candidates and leads of antioxidant therapy.


Assuntos
Elementos de Resposta Antioxidante , Diterpenos/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Animais , Antioxidantes/farmacologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Homeostase , Neoplasias Hepáticas/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Oxirredução , Oxigênio/química , Poluição por Fumaça de Tabaco , Peixe-Zebra
19.
Nat Cell Biol ; 21(4): 476-486, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30858581

RESUMO

The capacity of cells to alter bioenergetics in response to the demands of various biological processes is essential for normal physiology. The coordination of energy sensing and production with highly energy-demanding cellular processes, such as cell division, is poorly understood. Here, we show that a cell cycle-dependent mitochondrial Ca2+ transient connects energy sensing to mitochondrial activity for mitotic progression. The mitochondrial Ca2+ uniporter (MCU) mediates a rapid mitochondrial Ca2+ transient during mitosis. Inhibition of mitochondrial Ca2+ transients via MCU depletion causes spindle checkpoint-dependent mitotic delay. Cellular ATP levels drop during early mitosis, and the mitochondrial Ca2+ transients boost mitochondrial respiration to restore energy homeostasis. This is achieved through mitosis-specific MCU phosphorylation and activation by the mitochondrial translocation of energy sensor AMP-activated protein kinase (AMPK). Our results establish a critical role for AMPK- and MCU-dependent mitochondrial Ca2+ signalling in mitosis and reveal a mechanism of mitochondrial metabolic adaptation to acute cellular energy stress.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Canais de Cálcio/fisiologia , Cálcio/metabolismo , Mitocôndrias/metabolismo , Mitose , Trifosfato de Adenosina/biossíntese , Animais , Canais de Cálcio/genética , Linhagem Celular , Células Cultivadas , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Microtúbulos/metabolismo , Mitocôndrias/enzimologia
20.
Cell ; 176(6): 1447-1460.e14, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30799039

RESUMO

The presence of DNA in the cytoplasm is normally a sign of microbial infections and is quickly detected by cyclic GMP-AMP synthase (cGAS) to elicit anti-infection immune responses. However, chronic activation of cGAS by self-DNA leads to severe autoimmune diseases for which no effective treatment is available yet. Here we report that acetylation inhibits cGAS activation and that the enforced acetylation of cGAS by aspirin robustly suppresses self-DNA-induced autoimmunity. We find that cGAS acetylation on either Lys384, Lys394, or Lys414 contributes to keeping cGAS inactive. cGAS is deacetylated in response to DNA challenges. Importantly, we show that aspirin can directly acetylate cGAS and efficiently inhibit cGAS-mediated immune responses. Finally, we demonstrate that aspirin can effectively suppress self-DNA-induced autoimmunity in Aicardi-Goutières syndrome (AGS) patient cells and in an AGS mouse model. Thus, our study reveals that acetylation contributes to cGAS activity regulation and provides a potential therapy for treating DNA-mediated autoimmune diseases.


Assuntos
DNA/imunologia , Nucleotidiltransferases/metabolismo , Tolerância a Antígenos Próprios/imunologia , Acetilação , Sequência de Aminoácidos , Animais , Aspirina/farmacologia , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Autoimunes do Sistema Nervoso/metabolismo , Autoimunidade , Linhagem Celular , DNA/genética , DNA/metabolismo , Modelos Animais de Doenças , Exodesoxirribonucleases/metabolismo , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Mutação , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/imunologia , Malformações do Sistema Nervoso/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Células THP-1
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