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1.
Cell ; 187(4): 846-860.e17, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262409

RESUMO

RNAs localizing to the outer cell surface have been recently identified in mammalian cells, including RNAs with glycan modifications known as glycoRNAs. However, the functional significance of cell surface RNAs and their production are poorly known. We report that cell surface RNAs are critical for neutrophil recruitment and that the mammalian homologs of the sid-1 RNA transporter are required for glycoRNA expression. Cell surface RNAs can be readily detected in murine neutrophils, the elimination of which substantially impairs neutrophil recruitment to inflammatory sites in vivo and reduces neutrophils' adhesion to and migration through endothelial cells. Neutrophil glycoRNAs are predominantly on cell surface, important for neutrophil-endothelial interactions, and can be recognized by P-selectin (Selp). Knockdown of the murine Sidt genes abolishes neutrophil glycoRNAs and functionally mimics the loss of cell surface RNAs. Our data demonstrate the biological importance of cell surface glycoRNAs and highlight a noncanonical dimension of RNA-mediated cellular functions.


Assuntos
Células Endoteliais , Infiltração de Neutrófilos , Neutrófilos , RNA , Animais , Camundongos , Células Endoteliais/metabolismo , Neutrófilos/metabolismo , RNA/química , RNA/metabolismo , Proteínas de Transporte de Nucleotídeos/genética , Proteínas de Transporte de Nucleotídeos/metabolismo
2.
J Immunol ; 211(3): 462-473, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37326485

RESUMO

Cell spreading is an initial and critical step in neutrophil adhesion and migration, leading to neutrophil recruitment to inflammatory tissues. Sideroflexin (Sfxn) family proteins are metabolite transporters located in the mitochondrial membrane. Recombinant SFXN5 protein is a citrate transporter in vitro; however, whether Sfxn5 regulates any cellular behavior or function remains unknown. In this study, we found that small interfering RNA transfection or morpholino injection achieving Sfxn5 deficiency in neutrophils significantly decreased neutrophil recruitment in mice and zebrafish, respectively. Sfxn5 deficiency impaired neutrophil spreading and spreading-associated cellular phenotypes, such as cell adhesion, chemotaxis, and ROS production. Actin polymerization is critical for neutrophil spreading, and we found that actin polymerization in spreading neutrophils was partially inhibited by Sfxn5 deficiency. Mechanistically, we observed that the levels of cytosolic citrate and its downstream metabolic products, acetyl-CoA and cholesterol, were decreased in Sfxn5-deficient neutrophils. The levels of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a mediator for the regulation of actin polymerization by cholesterol, were reduced in the plasma membrane of Sfxn5-deficient neutrophils. Exogenous supplementation with citrate or cholesterol partially reversed the reduction in PI(4,5)P2 levels, defective neutrophil actin polymerization, and cell spreading. Altogether, we demonstrated that Sfxn5 maintains cytosolic citrate levels and ensures the synthesis of sufficient cholesterol to promote actin polymerization in a PI(4,5)P2-dependent manner during neutrophil spreading, which is essential for the eventual inflammatory recruitment of neutrophils. Our study revealed the importance of Sfxn5 in neutrophil spreading and migration, thus identifying, to our knowledge, for the first time, the physiological cellular functions of the Sfxn5 gene.


Assuntos
Actinas , Neutrófilos , Animais , Camundongos , Actinas/metabolismo , Neutrófilos/metabolismo , Ácido Cítrico/metabolismo , Peixe-Zebra/metabolismo , Polimerização , Colesterol/metabolismo
3.
J Transl Med ; 22(1): 117, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291470

RESUMO

BACKGROUND: Radioresistance is a primary factor contributing to the failure of rectal cancer treatment. Immune suppression plays a significant role in the development of radioresistance. We have investigated the potential role of phosphatidylinositol transfer protein cytoplasmic 1 (PITPNC1) in regulating immune suppression associated with radioresistance. METHODS: To elucidate the mechanisms by which PITPNC1 influences radioresistance, we established HT29, SW480, and MC38 radioresistant cell lines. The relationship between radioresistance and changes in the proportion of immune cells was verified through subcutaneous tumor models and flow cytometry. Changes in the expression levels of PITPNC1, FASN, and CD155 were determined using immunohistochemistry and western blotting techniques. The interplay between these proteins was investigated using immunofluorescence co-localization and immunoprecipitation assays. Additionally, siRNA and lentivirus-mediated gene knockdown or overexpression, as well as co-culture of tumor cells with PBMCs or CD8+ T cells and establishment of stable transgenic cell lines in vivo, were employed to validate the impact of the PITPNC1/FASN/CD155 pathway on CD8+ T cell immune function. RESULTS: Under irradiation, the apoptosis rate and expression of apoptosis-related proteins in radioresistant colorectal cancer cell lines were significantly decreased, while the cell proliferation rate increased. In radioresistant tumor-bearing mice, the proportion of CD8+ T cells and IFN-γ production within immune cells decreased. Immunohistochemical analysis of human and animal tissue specimens resistant to radiotherapy showed a significant increase in the expression levels of PITPNC1, FASN, and CD155. Gene knockdown and rescue experiments demonstrated that PITPNC1 can regulate the expression of CD155 on the surface of tumor cells through FASN. In addition, co-culture experiments and in vivo tumor-bearing experiments have shown that silencing PITPNC1 can inhibit FASN/CD155, enhance CD8+ T cell immune function, promote colorectal cancer cell death, and ultimately reduce radioresistance in tumor-bearing models. CONCLUSIONS: PITPNC1 regulates the expression of CD155 through FASN, inhibits CD8+ T cell immune function, and promotes radioresistance in rectal cancer.


Assuntos
Neoplasias Colorretais , Neoplasias Retais , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Técnicas de Cocultura , Neoplasias Colorretais/genética , Ácido Graxo Sintase Tipo I/metabolismo , Imunidade , Neoplasias Retais/radioterapia
4.
BMC Cancer ; 24(1): 133, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273249

RESUMO

PURPOSE: There are limited and no standard therapies for recurrent glioblastoma. We herein report the antitumour activity and safety of sintilimab, bevacizumab and temozolomide (TMZ) in recurrent glioblastoma. METHODS: We retrospectively analysed eight patients with recurrent glioblastoma treated with sintilimab (200 mg) every three weeks + bevacizumab (10 mg/kg) every three weeks + TMZ (200 mg/m²orally) (5 days orally every 28 days for a total of four weeks). The primary objective was investigator-assessed median progression-free survival(mPFS). Secondary objectives were to assess the 6-month PFS, objective response rate (ORR) and duration of response (DOR) accroding to RANO criteria. RESULTS: The mPFS time for 8 patients was 3.340 months (95% CI: 2.217-4.463), The longest PFS was close to 9 months. Five patients were assessed to have achieved partial response (PR), with an overall remission rate of 62.5%, Four patients experienced a change in tumour volume at the best response time of greater than 60% shrinkage from baseline, and one patient remained progression free upon review, with a DOR of more than 6.57 months. The 6-month PFS was 25% (95% CI: 5.0-55.0%). Three patients had a treatment-related adverse events, though no grade 4 or 5 adverse events occurred. CONCLUSION: In this small retrospective study, the combination regimen of sintilimab, bevacizumab and TMZ showed promising antitumour activity in treatment of recurrent glioblastoma, with a good objective remission rate.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Bevacizumab/efeitos adversos , Estudos Retrospectivos , Dacarbazina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia
5.
J Immunol ; 209(4): 723-730, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35914834

RESUMO

Severe acute respiratory syndrome coronavirus 2, responsible for the severe acute respiratory syndrome known as COVID-19, has rapidly spread in almost every country and devastated the global economy and health care system. Lung injury is an early disease manifestation believed to be a major contributor to short- and long-term pathological consequences of COVID-19, and thus drug discovery aiming to ameliorate lung injury could be a potential strategy to treat COVID-19 patients. By inducing a severe acute respiratory syndrome-like pulmonary disease model through infecting A/J mice with murine hepatitis virus strain 1 (MHV-1), we show that i.v. administration of pazopanib ameliorates acute lung injuries without affecting MHV-1 replication. Pazopanib reduces cell apoptosis in MHV-1-infected lungs. Furthermore, we also identified that pazopanib has to be given no later than 48 h after the virus infection without compromising the therapeutic effect. Our study provides a potential treatment for coronavirus-induced lung injuries and support for further evaluation of pazopanib in COVID-19 patients.


Assuntos
Tratamento Farmacológico da COVID-19 , Lesão Pulmonar , Vírus da Hepatite Murina , Animais , Indazóis , Pulmão , Lesão Pulmonar/tratamento farmacológico , Camundongos , Pirimidinas , Sulfonamidas/uso terapêutico
6.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838931

RESUMO

Radix Vicatia thibetica de Boiss (RVT) is locally known as "Xigui" or "Dujiao-danggui" in Tibetan medicine and is often used as a substitute for Radix Angelica sinensis (RAS) in daily nourishing diets and clinical applications. In this study, we determined and compared the contents of polysaccharides, total coumarins, ferulic acid, total phenols, total flavonoids, chlorogenic acid, protein, and amino acids, and the composition of volatile oil in RVT and RAS. Biological activities, including antioxidants, scavenging of nitrite, inhibition of tyrosinase, thrombin, and coagulation FXa, were comparatively evaluated. Results showed that RVT contains more polysaccharides, phenols, flavonoids, proteins, glutamic acid, and lysine as compared to RAS. Among volatile compounds, 14 species are similar, and 20 species are different in RVT and RAS. Overall, among volatile compounds, the content of 3-N-Butylphthalide was higher, whereas the content of ligustilide was lower in RVT volatile oil. A significant difference was reported in the bioactivity of RVT and RAS. The biological activity of RVT had higher antioxidant, nitrite scavenging, and tyrosinase inhibitory activities, whereas it showed much lower thrombin and FXa inhibitory activities. Correlation analysis showed that the antioxidant, nitrite scavenging, and tyrosinase inhibitory activities were related to the phenol and flavonoid content, whereas the thrombin and FXa inhibitory activities were related to ferulic acid and volatile oil content. This study presents a comparative analysis of RAS and RVT's chemical compositions of antioxidant, nitrite-scavenging, inhibition of tyrosinase, thrombin, and coagulation FXa activities. It was found that both RVT and RAS have their unique advantages, and RVT has the potential to be utilized as functional foods, cosmetics, and medical products.


Assuntos
Angelica sinensis , Óleos Voláteis , Antioxidantes/química , Angelica sinensis/química , Nitritos , Monofenol Mono-Oxigenase , Trombina , Fenóis , Flavonoides/farmacologia , Óleos Voláteis/química , Extratos Vegetais/química , Polissacarídeos
7.
J Immunol ; 204(4): 1012-1021, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31924649

RESUMO

Cell polarization is a key step for leukocytes adhesion and transmigration during leukocytes' inflammatory infiltration. Polarized localization of plasma membrane (PM) phosphatidylinositol-4-phosphate (PtdIns4P) directs the polarization of RPH3A, which contains a PtdIns4P binding site. Consequently, RPH3A mediates the RAB21 and PIP5K1C90 polarization, which is important for neutrophil adhesion to endothelia during inflammation. However, the mechanism by which RPH3A is recruited only to PM PtdIns4P rather than Golgi PtdIns4P remains unclear. By using ADP-ribosylation factor 6 (ARF6) small interfering RNA, ARF6 dominant-negative mutant ARF6(T27N), and ARF6 activation inhibitor SecinH3, we demonstrate that ARF6 plays an important role in the polarization of RPH3A, RAB21, and PIP5K1C90 in murine neutrophils. PM ARF6 is polarized and colocalized with RPH3A, RAB21, PIP5K1C90, and PM PtdIns4P in mouse and human neutrophils upon integrin stimulation. Additionally, ARF6 binds to RPH3A and enhances the interaction between the PM PtdIns4P and RPH3A. Consistent with functional roles of polarization of RPH3A, Rab21, and PIP5K1C90, ARF6 is also required for neutrophil adhesion on the inflamed endothelial layer. Our study reveals a previously unknown role of ARF6 in neutrophil polarization as being the coincidence-detection code with PM PtdIns4P. Cooperation of ARF6 and PM PtdIns4P direct RPH3A polarization, which is important for neutrophil firm adhesion to endothelia.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Endotélio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ativação de Neutrófilo , Neutrófilos/imunologia , Proteínas de Transporte Vesicular/metabolismo , Fator 6 de Ribosilação do ADP , Animais , Adesão Celular/imunologia , Linhagem Celular , Membrana Celular/metabolismo , Movimento Celular/imunologia , Células Endoteliais , Endotélio/citologia , Endotélio/imunologia , Feminino , Voluntários Saudáveis , Humanos , Camundongos , Neutrófilos/citologia , Neutrófilos/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Cultura Primária de Células , Rabfilina-3A
8.
Int J Mol Sci ; 23(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35682933

RESUMO

Being in the epicenter of the COVID-19 pandemic, our lab tested 193,054 specimens for SARS-CoV-2 RNA by diagnostic multiplex reverse transcription polymerase chain reaction (mRT-PCR) starting in March 2020, of which 17,196 specimens resulted positive. To investigate the dynamics of virus molecular evolution and epidemiology, whole genome amplification (WGA) and Next Generation Sequencing (NGS) were performed on 9516 isolates. 7586 isolates with a high quality were further analyzed for the mutation frequency and spectrum. Lastly, we evaluated the utility of the mRT-PCR detection pattern among 26 reinfected patients with repeat positive testing three months after testing negative from the initial infection. Our results show a continuation of the genetic divergence in viral genomes. Furthermore, our results indicate that independent mutations in the primer and probe regions of the nucleocapsid gene amplicon and envelope gene amplicon accumulate over time. Some of these mutations correlate with the changes of detection pattern of viral targets of mRT-PCR. Our data highlight the significance of a continuous genetic divergence on a gene amplification-based assay, the value of the mRT-PCR detection pattern for complementing the clinical diagnosis of reinfection, and the potential for WGA and NGS to identify mutation hotspots throughout the entire viral genome to optimize the design of the PCR-based gene amplification assay.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/genética , Teste para COVID-19 , Técnicas de Laboratório Clínico/métodos , Humanos , Reação em Cadeia da Polimerase Multiplex , Pandemias , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , Sensibilidade e Especificidade
9.
J Cell Biochem ; 120(11): 18871-18882, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31218746

RESUMO

Autophagy refers to the genetically regulated process to regulate the survival and death of cells, which is conserved in evolution. Typically, autophagy exerts a vital part under physiopathological conditions. Whether autophagy can be resulted from chronic intermittent hypoxia (CIH), a prominent characteristic of obstructive sleep apnea-hypopnea syndrome (OSAHS), remains to be investigated. Furthermore, microRNAs (miRNAs) can serve as the regulating factors in a variety of benign and malignant diseases; nonetheless, it remains to be fully illustrated about the way by which miRNAs modulate autophagy. According to our results, for human coronary artery endothelial cells (HCAECs), CIH increased the expression of autophagy-associated proteins, which depended on the concentration and time; besides, it could promote autophagic vacuole (AV) formation. In addition, CIH could activate beclin 1, which was dependent on dose and time. In HCAECs, microRNA-34a-5p (miR-34a-5p) was overexpressed after exposed to CIH, and its target protein B-cell lymphoma 2 (Bcl-2) was downregulated. Moreover, inhibiting miR-34a-5p increased Bcl-2 and p62 expression, while downregulating beclin 1, Vps34, Atg5, and LC3 levels, implying the role of miR-34a-5p in CIH-induced autophagy. Moreover, exogenous upregulation of Bcl-2 could block miR-34a-5p influence on CIH-induced autophagy through suppressing beclin 1 expression. Additionally, beclin 1 could enhance the autophagy induced by CIH. In conclusion, overexpression of miR-34a-5p activated beclin 1 through Bcl-2 inhibition in CIH and participated in CIH-induced autophagy.


Assuntos
Morte Celular Autofágica , Proteína Beclina-1/metabolismo , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Beclina-1/genética , Hipóxia Celular , Vasos Coronários/patologia , Células Endoteliais/patologia , Humanos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética
10.
Immunity ; 33(3): 340-50, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20850356

RESUMO

Neutrophils are important in innate immunity and acute inflammatory responses. However, the regulation of their recruitment to sites of inflammation has not been well characterized. Here, we investigated the kinase PIP5K1C and showed that PIP5K1C deficiency impaired neutrophil recruitment because of an adhesion defect. PIP5K1C regulated the adhesion through facilitating RhoA GTPase and integrin activation by chemoattractants. Integrins could induce polarization of an isoform of PIP5K1C, PIP5K1C-90, in neutrophils through intracellular vesicle transport independently of exogenous chemoattractant. PIP5K1C-90 polarization was required for polarized RhoA activation at uropods and provided an initial directional cue for neutrophil polarization on the endothelium. Importantly, the polarization was also required for circumventing the inhibition of lamellipodium formation by RhoA so that neutrophils could form leading edges required for transendothelial migration. Because integrins are not known to regulate neutrophil polarization, our study revealed a previously underappreciated role of integrin signaling in neutrophil regulation.


Assuntos
Integrinas/fisiologia , Infiltração de Neutrófilos , Neutrófilos/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/fisiologia , Animais , Adesão Celular , Movimento Celular , Polaridade Celular , Quimiotaxia de Leucócito , Células Endoteliais/fisiologia , Camundongos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Neutrófilos/imunologia , Fosforilação , Vesículas Transportadoras/fisiologia , Proteínas rho de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP
11.
Proc Natl Acad Sci U S A ; 112(31): 9644-9, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26195787

RESUMO

The serine-threonine kinase Akt is a key regulator of cell proliferation and survival, glucose metabolism, cell mobility, and tumorigenesis. Activation of Akt by extracellular stimuli such as insulin centers on the interaction of Akt with PIP3 on the plasma membrane, where it is subsequently phosphorylated and activated by upstream protein kinases. However, it is not known how Akt is recruited to the plasma membrane upon stimulation. Here we report that ubiquitin-like protein 4A (Ubl4A) plays a crucial role in insulin-induced Akt plasma membrane translocation. Ubl4A knockout newborn mice have defective Akt-dependent glycogen synthesis and increased neonatal mortality. Loss of Ubl4A results in the impairment of insulin-induced Akt translocation to the plasma membrane and activation. Akt binds actin-filaments and colocalizes with actin-related protein 2 and 3 (Arp2/3) complex in the membrane ruffles and lamellipodia. Ubl4A directly interacts with Arp2/3 to accelerate actin branching and networking, allowing Akt to be in close proximity to the plasma membrane for activation upon insulin stimulation. Our finding reveals a new mechanism by which Akt is recruited to the plasma membrane for activation, thereby providing a missing link in Akt signaling.


Assuntos
Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Membrana Celular/enzimologia , Insulina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitinas/metabolismo , Actinas/metabolismo , Animais , Animais Recém-Nascidos , Membrana Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Embrião de Mamíferos/citologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glicogênio/biossíntese , Proteínas de Fluorescência Verde/metabolismo , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Pseudópodes/efeitos dos fármacos , Pseudópodes/metabolismo , Ubiquitinas/deficiência
12.
J Cell Sci ; 128(5): 992-1000, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25588844

RESUMO

A hallmark of neutrophil polarization is the back localization of active RHOA and phosphorylated myosin light chain (pMLC, also known as MYL2). However, the mechanism for the polarization is not entirely clear. Here, we show that FAM65B, a newly identified RHOA inhibitor, is important for the polarization. When FAM65B is phosphorylated, it binds to 14-3-3 family proteins and becomes more stable. In neutrophils, chemoattractants stimulate FAM65B phosphorylation largely depending on the signals from the front of the cells that include those mediated by phospholipase Cß (PLCß) and phosphoinositide 3-kinase γ (PI3Kγ), leading to FAM65B accumulation at the leading edge. Concordantly, FAM65B deficiency in neutrophils resulted in an increase in RHOA activity and localization of pMLC to the front of cells, as well as defects in chemotaxis directionality and adhesion to endothelial cells under flow. These data together elucidate a mechanism for RHOA and pMLC polarization in stimulated neutrophils through direct inhibition of RHOA by FAM65B at the leading edge.


Assuntos
Neutrófilos/metabolismo , Proteínas/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Adesão Celular/fisiologia , Moléculas de Adesão Celular , Quimiotaxia/fisiologia , Classe Ib de Fosfatidilinositol 3-Quinase , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Cadeias Leves de Miosina/genética , Cadeias Leves de Miosina/metabolismo , Neutrófilos/citologia , Fosfolipase C beta/genética , Fosfolipase C beta/metabolismo , Fosforilação/fisiologia , Proteínas/genética , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/genética
13.
Blood ; 123(19): 3027-36, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24574460

RESUMO

Serum response factor (SRF) is a ubiquitously expressed transcription factor and master regulator of the actin cytoskeleton. We have previously shown that SRF is essential for megakaryocyte maturation and platelet formation and function. Here we elucidate the role of SRF in neutrophils, the primary defense against infections. To study the effect of SRF loss in neutrophils, we crossed Srf(fl/fl) mice with select Cre-expressing mice and studied neutrophil function in vitro and in vivo. Despite normal neutrophil numbers, neutrophil function is severely impaired in Srf knockout (KO) neutrophils. Srf KO neutrophils fail to polymerize globular actin to filamentous actin in response to N-formyl-methionine-leucine-phenylalanine, resulting in significantly disrupted cytoskeletal remodeling. Srf KO neutrophils fail to migrate to sites of inflammation in vivo and along chemokine gradients in vitro. Polarization in response to cytokine stimuli is absent and Srf KO neutrophils show markedly reduced adhesion. Integrins play an essential role in cellular adhesion, and although integrin expression levels are maintained with loss of SRF, integrin activation and trafficking are disrupted. Migration and cellular adhesion are essential for normal cell function, but also for malignant processes such as metastasis, underscoring an essential function for SRF and its pathway in health and disease.


Assuntos
Movimento Celular/genética , Inflamação/genética , Neutrófilos/metabolismo , Fator de Resposta Sérica/genética , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Western Blotting , Adesão Celular/genética , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Quimiocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação/fisiopatologia , Integrinas/genética , Integrinas/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Polimerização/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Resposta Sérica/deficiência , Fator de Resposta Sérica/fisiologia , Transdução de Sinais/genética
14.
Nat Commun ; 15(1): 3068, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594269

RESUMO

Polyunsaturated fatty acids (PUFAs), which cannot be synthesized by animals and must be supplied from the diet, have been strongly associated with human health. However, the mechanisms for their accretion remain poorly understood. Here, we show that LDL receptor-related protein 5 (LRP5), but not its homolog LRP6, selectively transports unesterified PUFAs into a number of cell types. The LDLa ligand-binding repeats of LRP5 directly bind to PUFAs and are required and sufficient for PUFA transport. In contrast to the known PUFA transporters Mfsd2a, CD36 and FATP2, LRP5 transports unesterified PUFAs via internalization to intracellular compartments including lysosomes, and n-3 PUFAs depend on this transport mechanism to inhibit mTORC1. This LRP5-mediated PUFA transport mechanism suppresses extracellular trap formation in neutrophils and protects mice from myocardial injury during ischemia-reperfusion. Thus, this study reveals a biologically important mechanism for unesterified PUFA transport to intracellular compartments.


Assuntos
Ácidos Graxos Ômega-3 , Ácidos Graxos Insaturados , Animais , Humanos , Camundongos , Dieta , Ácidos Graxos/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Insaturados/metabolismo , Receptores de LDL
15.
Biomed Rep ; 21(2): 111, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38912168

RESUMO

Retinopathy of prematurity (ROP) is a retinopathy caused by abnormal proliferation of blood vessels in premature infants. It can lead to retinal detachment and, in severe cases, blindness, rendering ROP a critical condition. Advances in neonatal medicine have improved survival rates of low birth weight and low gestational age infants. However, this progress has also led to a rise in incidence of ROP. Currently, premature birth, low birth weight and high postpartum oxygen levels are independent risk factors for ROP. Other factors include mode of delivery, multiple births, anemia, blood transfusion, maternal pregnancy factors, neonatal bronchopulmonary dysplasia, use of surfactants, arterial ductus arteriosus and necrotizing enterocolitis. Laboratory indicators in premature infants such as platelet count, levels of blood glucose, inflammatory cells, lipid and hemoglobin and blood transfusion may also be associated with ROP. However, the etiology and pathogenesis of ROP are not fully understood. A number of factors may influence the onset and progression of ROP, including decreased platelet counts, decreased hemoglobin levels, increased white blood cell counts, increased blood glucose levels, and disorders of lipid metabolism. The present study reviewed the effects of platelet count, hemoglobin, blood glucose, inflammatory cells and factors, blood lipids, and plasma metabolic pathways on ROP.

16.
World J Clin Oncol ; 15(1): 89-114, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38292658

RESUMO

BACKGROUND: A recently hypothesized cause of cell death called disulfidptosis has been linked to the expansion, emigration, and vascular rebuilding of cancer cells. Cancer can be treated by targeting the pathways that trigger cell death. AIM: To discover the long non-coding RNA of the disulfidaptosis-related lncRNAs (DRLs), prognosis clinical survival, and treat patients with colorectal cancer with medications. METHODS: Initially, we queried the Cancer Genome Atlas database to collect transcriptome, clinical, and genetic mutation data for colorectal cancer (CRC). Training and testing sets for CRC patient transcriptome data were generated randomly. Key long non-coding RNAs (lncRNAs) related to DRLs were then identified and evaluated using a least absolute shrinkage and selection operator procedure, as well as univariate and multivariate Cox regression models. A prognostic model was then created after risk scoring. Also, Immune infiltration analysis, immune checkpoint analysis, and medication susceptibility analysis were used to investigate the causes of the different prognoses between high and low risk groups. Finally, we validated the differential expression and biomarker potential of risk-predictive lncRNAs through induction using both NCM460 and HT-29 cell lines, as well as a disulfidptosis model. RESULTS: In this work, eight significant lncRNAs linked to disulfidptosis were found. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of differentially expressed genes between high- and low-risk groups from the prognostic model showed a close relationship with the immune response as well as significant enrichment in neutrophil extracellular trap formation and the IL-17 signaling pathway. Furthermore, significant immune cell variations between the high-risk and low-risk groups were seen, as well as a higher incidence of immunological escape risk in the high-risk group. Finally, Epirubicin, bortezomib, teniposide, and BMS-754807 were shown to have the lowest sensitivity among the four immunotherapy drugs. CONCLUSION: Our findings emphasizes the role of disulfidptosis in regulating tumor development, therapeutic response, and patient survival in CRC patients. For the clinical treatment of CRC, these important LncRNAs could serve as viable therapeutic targets.

17.
Nat Commun ; 15(1): 603, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38242867

RESUMO

CD8+ T cells play an important role in anti-tumor immunity. Better understanding of their regulation could advance cancer immunotherapies. Here we identify, via stepwise CRISPR-based screening, that CUL5 is a negative regulator of the core signaling pathways of CD8+ T cells. Knocking out CUL5 in mouse CD8+ T cells significantly improves their tumor growth inhibiting ability, with significant proteomic alterations that broadly enhance TCR and cytokine signaling and their effector functions. Chemical inhibition of neddylation required by CUL5 activation, also enhances CD8 effector activities with CUL5 validated as a major target. Mechanistically, CUL5, which is upregulated by TCR stimulation, interacts with the SOCS-box-containing protein PCMTD2 and inhibits TCR and IL2 signaling. Additionally, CTLA4 is markedly upregulated by CUL5 knockout, and its inactivation further enhances the anti-tumor effect of CUL5 KO. These results together reveal a negative regulatory mechanism for CD8+ T cells and have strong translational implications in cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Proteínas Culina , Ubiquitina-Proteína Ligases , Animais , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Proteínas Culina/genética , Proteínas Culina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Proteômica , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
World J Gastroenterol ; 30(20): 2709-2725, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38855154

RESUMO

BACKGROUND: Constipation, a highly prevalent functional gastrointestinal disorder, induces a significant burden on the quality of patients' life and is associated with substantial healthcare expenditures. Therefore, identifying efficient therapeutic modalities for constipation is of paramount importance. Oxidative stress is a pivotal contributor to colonic dysmotility and is the underlying pathology responsible for constipation symptoms. Consequently, we postulate that hydrogen therapy, an emerging and promising intervention, can serve as a safe and efficacious treatment for constipation. AIM: To determine whether hydrogen-rich water (HRW) alleviates constipation and its potential mechanism. METHODS: Constipation models were established by orally loperamide to Sprague-Dawley rats. Rats freely consumed HRW, and were recorded their 24 h total stool weight, fecal water content, and charcoal propulsion rate. Fecal samples were subjected to 16S rDNA gene sequencing. Serum non-targeted metabolomic analysis, malondialdehyde, and superoxide dismutase levels were determined. Colonic tissues were stained with hematoxylin and eosin, Alcian blue-periodic acid-Schiff, reactive oxygen species (ROS) immunofluorescence, and immunohistochemistry for cell growth factor receptor kit (c-kit), PGP 9.5, sirtuin1 (SIRT1), nuclear factor-erythroid-2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). Quantitative real-time PCR and western blot analysis were conducted to determine the expression level of SIRT1, Nrf2 and HO-1. A rescue experiment was conducted by intraperitoneally injecting the SIRT1 inhibitor, EX527, into constipated rats. NCM460 cells were induced with H2O2 and treated with the metabolites to evaluate ROS and SIRT1 expression. RESULTS: HRW alleviated constipation symptoms by improving the total amount of stool over 24 h, fecal water content, charcoal propulsion rate, thickness of the intestinal mucus layer, c-kit expression, and the number of intestinal neurons. HRW modulated intestinal microbiota imbalance and abnormalities in serum metabolism. HRW could also reduce intestinal oxidative stress through the SIRT1/Nrf2/HO-1 signaling pathway. This regulatory effect on oxidative stress was confirmed via an intraperitoneal injection of a SIRT1 inhibitor to constipated rats. The serum metabolites, ß-leucine (ß-Leu) and traumatic acid, were also found to attenuate H2O2-induced oxidative stress in NCM460 cells by up-regulating SIRT1. CONCLUSION: HRW attenuates constipation-associated intestinal oxidative stress via SIRT1/Nrf2/HO-1 signaling pathway, modulating gut microbiota and serum metabolites. ß-Leu and traumatic acid are potential metabolites that upregulate SIRT1 expression and reduce oxidative stress.


Assuntos
Colo , Constipação Intestinal , Modelos Animais de Doenças , Hidrogênio , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuína 1 , Animais , Constipação Intestinal/metabolismo , Constipação Intestinal/tratamento farmacológico , Sirtuína 1/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ratos , Hidrogênio/farmacologia , Masculino , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Humanos , Água/metabolismo , Heme Oxigenase-1/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Fezes/química
19.
Eur J Pharmacol ; 975: 176634, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38710356

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with immune dysregulation affecting colon inflammatory response. Recent studies have highlighted that neutrophil extracellular traps (NETs) play an important role in the pathogenesis of UC. Berbamine (BBM), one of the bioactive ingredients extracted from Chinese herbal medicine Berberis vulgaris L, has attracted intensive attentions due to its significant anti-inflammatory activity and a marketing drug for treating leukemia in China. However, the exact role and potential molecular mechanism of BBM against UC remains elusive. In the present study, our results showed that BBM could markedly improve the pathological phenotype and the colon inflammation in mice with dextran sulfate sodium (DSS)-induced colitis. Then, comprehensive approaches combining network pharmacology and molecular docking analyses were employed to predict the therapeutic potential of BBM in treating UC by peptidyl-arginine deiminase 4 (PAD4), a crucial molecule involved in NETs formation. The molecular docking results showed BBM had a high affinity for PAD4 with a binding energy of -9.3 kcal/mol Moreover, PAD4 expression and NETs productions, including citrullination of histone H3 (Cit-H3), neutrophil elastase (NE), myeloperoxidase (MPO) in both neutrophils and colonic tissue were reduced after BBM administration. However, in the mice with DSS-induced colitis pretreated with GSK484, a PAD4-specific inhibitor, BBM could not further reduce disease related indexes, expression of PAD4 and NETs productions. Above all, the identification of PAD4 as a potential target for BBM to inhibit NETs formation in colitis provides novel insights into the development of BBM-derived drugs for the clinical management of UC.


Assuntos
Benzilisoquinolinas , Sulfato de Dextrana , Armadilhas Extracelulares , Simulação de Acoplamento Molecular , Proteína-Arginina Desiminase do Tipo 4 , Animais , Armadilhas Extracelulares/efeitos dos fármacos , Armadilhas Extracelulares/metabolismo , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Proteína-Arginina Desiminase do Tipo 4/antagonistas & inibidores , Camundongos , Benzilisoquinolinas/farmacologia , Benzilisoquinolinas/uso terapêutico , Benzilisoquinolinas/química , Masculino , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/patologia , Colite/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/imunologia , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Camundongos Endogâmicos C57BL , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/química , Modelos Animais de Doenças
20.
Int J Oncol ; 64(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38214378

RESUMO

Long­stranded non­coding RNAs (lncRNAs) are RNAs that consist of >200 nucleotides. The majority of lncRNAs do not encode proteins but have been revealed to mediate a variety of important physiological functions. Antisense­lncRNAs (AS­lncRNAs) are transcribed from the opposite strand of a protein or non­protein coding gene as part of the antisense strand of the coding gene. AS­lncRNAs can serve an important role in the tumorigenesis, prognosis, metastasis and drug resistance of a number of malignancies. This has been reported to be exerted through various mechanisms, such as endogenous competition, promoter interactions, direct interactions with mRNAs, acting as 'scaffolds' to regulate mRNA half­life, interactions with 5­untranslated regions and regulation of sense mRNAs. AS­lncRNAs have been found to either inhibit or promote tumor aggressiveness by regulating cell proliferation, energy metabolism, inflammation, inflammatory­carcinoma transformation, invasion, migration and angiogenesis. In addition, accumulating evidence has documented that AS­lncRNAs can regulate tumor therapy resistance. Therefore, targeting aberrantly expressed AS­lncRNAs for cancer treatment may prove to be a promising approach to reverse therapy resistance. In the present review, research advances on the role of AS­lncRNAs in tumor occurrence and development were summarized, with the aim of providing novel ideas for further research in this field.


Assuntos
Neoplasias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Neoplasias/genética , Regulação Neoplásica da Expressão Gênica
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