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1.
Mol Cell Biol ; 44(3): 87-102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38520226

RESUMO

Although LncRNA AA465934 expression is reduced in high glucose (HG)-treated podocytes, its role in HG-mediated podocyte injury and diabetic nephropathy (DN) remains unknown. Herein, we investigated the role of AA465934 in HG-mediated podocyte injury and DN using a spontaneous type II diabetic nephropathy (T2DN) model. The model was created by injecting AA465934 overexpressed adeno-associated virus (AAV) or control into mice. The levels of renal function, proteinuria, renal structural lesions, and podocyte apoptosis were then examined. Furthermore, AA465934 and autophagy levels, as well as tristetraprolin (TTP) and high mobility group box 1 (HMGB1) expression changes were detected. We also observed podocyte injury and the binding ability of TTP to E3 ligase proviral insertion in murine lymphomas 2 (PIM2), AA465934, or HMGB1. According to the results, AA465934 improved DN progression and podocyte damage in T2DN mice. In addition, AA465934 bound to TTP and inhibited its degradation by blocking TTP-PIM2 binding. Notably, TTP knock-down blocked the ameliorating effects of AA465934 and TTP bound HMGB1 mRNA, reducing its expression. Overexpression of HMGB1 inhibited the ability of AA465934 and TTP to improve podocyte injury. Furthermore, AA465934 bound TTP, inhibiting TTP-PIM2 binding, thereby suppressing TTP degradation, downregulating HMGB1, and reversing autophagy downregulation, ultimately alleviating HG-mediated podocyte injury and DN. Based on these findings, we deduced that the AA465934/TTP/HMGB1/autophagy axis could be a therapeutic avenue for managing podocyte injury and DN.


Assuntos
Nefropatias Diabéticas , Proteína HMGB1 , Podócitos , RNA Longo não Codificante , Animais , Camundongos , Apoptose , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Regulação para Baixo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Podócitos/metabolismo , Podócitos/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo
2.
BMC Res Notes ; 17(1): 82, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504371

RESUMO

OBJECTIVE: Tristetraprolin (TTP/ZFP36) family proteins exhibit antiinflammatory effects by destabilizing proinflammatory mRNAs. Previous studies showed that bacterial endotoxin lipopolysaccharides (LPS) stimulated TTP and tumor necrosis factor (TNF) gene expression, but less was known about LPS effects on TTP homologues and other proinflammatory gene expression in macrophages. The objective was to investigate LPS regulation of TTP family gene and TTP-targeted gene expression in mouse RAW264.7 macrophages using much higher concentrations of LPS and much longer treatment time than previous studies. RESULTS: MTT assay showed that LPS was not toxic to the cells under LPS treatment up to 1000 ng/mL for 2-24 h. LPS mildly affected the soluble protein content in the cells. qPCR assay showed that LPS stimulated TTP mRNA rapidly but not sustainably with 40, 10, and 3 fold of the DMSO control after 2, 8 and 24 h treatment, respectively. Immunoblotting confirmed qPCR results on LPS stimulation of TTP gene expression in the mouse macrophages. LPS exhibited minimal effects on ZFP36L1, ZFP36L2 and ZFP36L3 mRNA levels. LPS increased mRNA levels of TNF, COX2, GM-CSF, INFγ and IL12b up to 311, 418, 11, 9 and 4 fold, respectively. This study demonstrated that LPS did not affect macrophage viability, dramatically increased antiinflammatory TTP gene expression as well as proinflammatory TNF and COX2 gene expression but had only mild effects on TTP homologues and other proinflammatory cytokine gene expression in the mouse macrophages.


Assuntos
Lipopolissacarídeos , Tristetraprolina , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Macrófagos/metabolismo , Anti-Inflamatórios/farmacologia , Expressão Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação da Expressão Gênica
3.
Sci Rep ; 14(1): 3113, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326511

RESUMO

Loss of inflammatory effector function, such as cytokine production and proliferation, is a fundamental driver of failure in T cell therapies against solid tumors. Here, we used CRISPR/Cas9 to genetically disrupt ZFP36, an RNA binding protein that regulates the stability of mRNAs involved in T cell inflammatory function, such as the cytokines IL2 and IFNγ, in human T cells engineered with a clinical-stage mesothelin-targeting CAR to determine whether its disruption could enhance antitumor responses. ZFP36 disruption slightly increased antigen-independent activation and cytokine responses but did not enhance overall performance in vitro or in vivo in a xenograft tumor model with NSG mice. While ZFP36 disruption does not reduce the function of CAR-T cells, these results suggest that singular disruption of ZFP36 is not sufficient to improve their function and may benefit from a multiplexed approach.


Assuntos
Imunoterapia Adotiva , Mesotelina , Humanos , Animais , Camundongos , Imunoterapia Adotiva/métodos , Linfócitos T/metabolismo , Imunidade , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Tristetraprolina/genética
4.
STAR Protoc ; 5(1): 102807, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38165801

RESUMO

Here, we present a protocol for modulating the function of the Cth2 mRNA-binding protein (RBP) in Saccharomyces cerevisiae. We describe steps to amplify and integrate mutations in Cth2 that affect its stability and function. Next, we detail the functional assay to verify the activity of the wild-type and mutant versions of Cth2 in yeast cells. This protocol can be adopted to modify the function of other RBPs with their respective functional mutations. For complete details on the use and execution of this protocol, please refer to Patnaik et al. (2022).1.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo , Ferro/metabolismo
5.
Geroscience ; 46(1): 1271-1284, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37535204

RESUMO

Tristetraprolin (TTP), encoded by Zfp36 in mice, is one of the best-characterized tandem zinc-finger mRNA binding proteins involved in mRNA deadenylation and decay. TTPΔARE mice lack an AU-rich motif in the 3'-untranslated regions of TTP mRNA, leading to increased TTP mRNA stability and more TTP protein, resulting in elevated mRNA decay rates of TTP targets. We examined the effect of TTP overexpression on the hematopoietic system in both young and middle-aged mice using TTPΔARE mice and found alterations in blood cell frequencies, with loss of platelets and B220 cells and gains of eosinophils and T cells. TTPΔARE mice also have skewed primitive populations in the bone marrow, with increases in myeloid-biased hematopoietic stem cells (HSCs) but decreases in granulocyte/macrophage-biased multipotent progenitors (MPP3) in both young and middle-aged mice. Changes in the primitive cells' frequencies were associated with transcriptional alterations in the TTP overexpression cells specific to age as well as cell type. Regardless of age, there was a consistent elevation of transcripts regulated by TNFα and TGFß signaling pathways in both the stem and multipotent progenitor populations. HSCs with TTP overexpression had decreased reconstitution potential in murine transplants but generated hematopoietic environments that mitigated the inflammatory response to the collagen antibody-induced arthritis (CAIA) challenge, which models rheumatoid arthritis and other autoimmune disorders. This dampening of the inflammatory response was even present when there was only a small frequency of TTP overexpressing cells present in the middle-aged mice. We provide an analysis of the early hematopoietic compartments with elevated TTP expression in both young and middle-aged mice which inhibits the reconstitution potential of the HSCs but generates a hematopoietic system that provides dominant repression of induced inflammation.


Assuntos
Sistema Hematopoético , Tristetraprolina , Animais , Camundongos , Regiões 3' não Traduzidas , Modelos Animais de Doenças , Sistema Hematopoético/metabolismo , Inflamação/genética , Camundongos Knockout , Tristetraprolina/genética , Tristetraprolina/metabolismo
6.
Life Sci Alliance ; 7(1)2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903626

RESUMO

Members of the tristetraprolin (TTP) family of RNA-binding proteins can bind to and promote the decay of specific transcripts containing AU-rich motifs. ZFP36 (TTP) is best known for regulating pro-inflammatory cytokine expression in myeloid cells; however, its mammalian paralogues ZFP36L1 and ZFP36L2 have not been viewed as important in controlling inflammation. We knocked out these genes in myeloid cells in mice, singly and together. Single-gene myeloid-specific knockouts resulted in almost no spontaneous phenotypes. In contrast, mice with myeloid cell deficiency of all three genes developed severe inflammation, with a median survival of 8 wk. Macrophages from these mice expressed many more stabilized transcripts than cells from myeloid-specific TTP knockout mice; many of these encoded pro-inflammatory cytokines and chemokines. The failure of weight gain, arthritis, and early death could be prevented completely by two normal alleles of any of the three paralogues, and even one normal allele of Zfp36 or Zfp36l2 was enough to prevent the inflammatory phenotype. Our findings emphasize the importance of all three family members, acting in concert, in myeloid cell function.


Assuntos
Inflamação , Tristetraprolina , Camundongos , Animais , Tristetraprolina/genética , Tristetraprolina/metabolismo , Inflamação/genética , Inflamação/metabolismo , Células Mieloides/metabolismo , Macrófagos/metabolismo , Camundongos Knockout , Citocinas/metabolismo , Mamíferos/metabolismo
7.
RNA Biol ; 21(1): 1-15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38111129

RESUMO

Inhibition of apoptosis is one of the hallmarks of cancer and is a target of various therapeutic interventions. BIRC5 is an inhibitor of apoptosis that is aberrantly expressed in cancer leading to sustained growth of tumours. Post-transcriptional control mechanisms involving RNA-binding proteins and AU-rich elements (AREs) are fundamental to many cellular processes and changes in the expression or function of these proteins can promote an aberrant and pathological phenotype. BIRC5 mRNA has an ARE in its 3' UTR making it a candidate for regulation by the RNA binding proteins tristetraprolin (TTP) and HuR (ELAVL1). In this study, we investigated the binding of TTP and HuR by RNA-immunoprecipitation assays and found that these proteins were associated with BIRC5 mRNA to varying extents. Consequently, BIRC5 expression decreased when TTP was overexpressed and apoptosis was induced. In the absence of TTP, BIRC5 mRNA was stabilized, protein expression increased and the number of apoptotic cells declined. As an ARE-mRNA stabilizing protein, recombinant HuR led to upregulation of BIRC5 expression, whereas HuR silencing was concomitant with downregulation of BIRC5 mRNA and protein and increased cell death. Survival analyses demonstrated that increased TTP and low BIRC5 expression predicted an overall better prognosis compared to dysregulated TTP and high BIRC5. Thus, the results present a novel target of ARE-mediated post-transcriptional regulation.


Assuntos
Neoplasias da Mama , Tristetraprolina , Humanos , Feminino , Tristetraprolina/genética , Tristetraprolina/metabolismo , Survivina/genética , Survivina/metabolismo , Neoplasias da Mama/genética , Regiões 3' não Traduzidas , Apoptose/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Estabilidade de RNA/genética
8.
FASEB J ; 38(1): e23338, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038723

RESUMO

Tristetraprolin (TTP; also known as NUP475, GOS24, or TIS11), encoded by Zfp36, is an RNA-binding protein that regulates target gene expression by promoting mRNA decay and preventing translation. Although previous studies have indicated that TTP deficiency is associated with systemic inflammation and a catabolic-like skeletal phenotype, the mechanistic underpinnings remain unclear. Here, using both TTP-deficient (TTPKO) and myeloid-specific TTPKO (cTTPKO) mice, we reveal that global absence or loss of TTP in the myeloid compartment results in a reduced bone microarchitecture, whereas gain-of-function TTP knock-in (TTPKI) mice exhibit no significant loss of bone microarchitecture. Flow cytometry analysis revealed a significant immunosuppressive immune cell phenotype with increased monocytic myeloid-derived suppressor cells (M-MDSCs) in TTPKO and cTTPKO mice, whereas no significant changes were observed in TTPKI mice. Single-cell transcriptomic analyses of bone marrow myeloid progenitor cell populations indicated a dramatic increase in early MDSC marker genes for both cTTPKO and TTPKO bone marrow populations. Consistent with these phenotypic and transcriptomic data, in vitro osteoclastogenesis analysis of bone marrow M-MDSCs from cTTPKO and TTPKO displayed enhanced osteoclast differentiation and functional capacity. Focused transcriptomic analyses of differentiated M-MDSCs showed increased osteoclast-specific transcription factors and cell fusion gene expression. Finally, functional data showed that M-MDSCs from TTP loss-of-function mice were capable of osteoclastogenesis and bone resorption in a context-dependent manner. Collectively, these findings indicate that TTP plays a central role in regulating osteoclastogenesis through multiple mechanisms, including induction of M-MDSCs that appear to regulate skeletal phenotype.


Assuntos
Células Supressoras Mieloides , Tristetraprolina , Animais , Camundongos , Osteoclastos/metabolismo , Osteogênese , Fenótipo , Tristetraprolina/genética
9.
mBio ; 14(5): e0174223, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37707056

RESUMO

IMPORTANCE: Our findings define a novel role for ZIKV-induced TTP expression in regulating IFNß/IFNλ production in primary hBMECs and Sertoli cells. These cells comprise key physiological barriers subverted by ZIKV to access brain and testicular compartments and serve as reservoirs for persistent replication and dissemination. We demonstrate for the first time that the ARE-binding protein TTP is virally induced and post-transcriptionally regulates IFNß/IFNλ secretion. In ZIKV-infected hBMEC and Sertoli cells, TTP knockout increased IFNß/IFNλ secretion, while TTP expression blocked IFNß/IFNλ secretion. The TTP-directed blockade of IFN secretion permits ZIKV spread and persistence in hBMECs and Sertoli cells and may similarly augment ZIKV spread across IFNλ-protected placental barriers. Our work highlights the importance of post-transcriptional ZIKV regulation of IFN expression and secretion in cells that regulate viral access to protected compartments and defines a novel mechanism of ZIKV-regulated IFN responses which may facilitate neurovirulence and sexual transmission.


Assuntos
Infecção por Zika virus , Zika virus , Gravidez , Masculino , Feminino , Humanos , Células de Sertoli/metabolismo , Zika virus/fisiologia , Infecção por Zika virus/metabolismo , Tristetraprolina , Placenta/metabolismo , Replicação Viral
10.
Cell Death Dis ; 14(8): 527, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587140

RESUMO

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, with high morbidity and mortality worldwide. Although the dysregulation of BARX1 expression has been shown to be associated with malignant cancers, including NSCLC, the underlying mechanism remains elusive. In this study, we identified BARX1 as a common differentially expressed gene in lung squamous cell carcinoma and adenocarcinoma. Importantly, we uncovered a novel mechanism behind the regulation of BARX1, in which ZFP36 interacted with 3'UTR of BARX1 mRNA to mediate its destabilization. Loss of ZFP36 led to the upregulation of BARX1, which further promoted the proliferation, migration and invasion of NSCLC cells. In addition, the knockdown of BARX1 inhibited tumorigenicity in mouse xenograft. We demonstrated that BARX1 promoted the malignant phenotypes by transactivating a set of master oncogenes involved in the cell cycle, DNA synthesis and metastasis. Overall, our study provides insights into the mechanism of BARX1 actions in NSCLC and aids a better understanding of NSCLC pathogenesis.


Assuntos
Adenocarcinoma , Carcinoma Pulmonar de Células não Pequenas , Proteínas de Homeodomínio , Neoplasias Pulmonares , Fatores de Transcrição , Tristetraprolina , Animais , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Homeodomínio/genética , Neoplasias Pulmonares/genética , Oncogenes , Fenótipo , Fatores de Transcrição/genética , Tristetraprolina/genética
11.
Biochim Biophys Acta Gene Regul Mech ; 1866(3): 194959, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37453649

RESUMO

Sterol synthesis is an iron-dependent metabolic pathway in eukaryotes. Consequently, fungal ergosterol biosynthesis (ERG) is down-regulated in response to iron deficiency. In this report, we show that, upon iron limitation or overexpression of the iron-regulated mRNA-binding protein Cth2, the yeast Saccharomyces cerevisiae down-regulates the three initial enzymatic steps of ergosterol synthesis (ERG1, ERG7 and ERG11). Mechanistically, we show that Cth2 protein limits the translation and promotes the decrease in the mRNA levels of these specific ERG genes, which contain consensus Cth2-binding sites defined as AU-rich elements (AREs). Thus, expression of CTH2 leads to the accumulation of initial sterol intermediates, such as squalene, and to the drop of ergosterol levels. Changes in CTH2 expression levels disturb the response of yeast cells to stresses related to membrane integrity such as high ethanol and sorbitol concentrations. Therefore, CTH2 should be considered as a critical regulatory factor of ergosterol biosynthesis during iron deficiency.


Assuntos
Deficiências de Ferro , Proteínas de Saccharomyces cerevisiae , Humanos , Ergosterol/metabolismo , Ferro/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Esteróis/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo
12.
Biomolecules ; 13(4)2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37189372

RESUMO

Gossypol is a complex plant polyphenol reported to be cytotoxic and anti-inflammatory, but little is known about its effect on gene expression in macrophages. The objective of this study was to explore gossypol's toxicity and its effect on gene expression involved in the inflammatory response, glucose transport and insulin signaling pathways in mouse macrophages. Mouse RAW264.7 macrophages were treated with multiple concentrations of gossypol for 2-24 h. Gossypol toxicity was estimated by MTT assay and soluble protein content. qPCR analyzed the expression of anti-inflammatory tristetraprolin family (TTP/ZFP36), proinflammatory cytokine, glucose transporter (GLUT) and insulin signaling genes. Cell viability was greatly reduced by gossypol, accompanied with a dramatic reduction in soluble protein content in the cells. Gossypol treatment resulted in an increase in TTP mRNA level by 6-20-fold and increased ZFP36L1, ZFP36L2 and ZFP36L3 mRNA levels by 26-69-fold. Gossypol increased proinflammatory cytokine TNF, COX2, GM-CSF, INFγ and IL12b mRNA levels up to 39-458-fold. Gossypol treatment upregulated mRNA levels of GLUT1, GLUT3 and GLUT4 genes as well as INSR, AKT1, PIK3R1 and LEPR, but not APP genes. This study demonstrated that gossypol induced macrophage death and reduced soluble protein content, which was accompanied with the massive stimulation of anti-inflammatory TTP family and proinflammatory cytokine gene expression, as well as the elevation of gene expression involved in glucose transport and the insulin signaling pathway in mouse macrophages.


Assuntos
Gossipol , Polifenóis , Camundongos , Animais , Polifenóis/farmacologia , Polifenóis/metabolismo , Gossipol/farmacologia , Macrófagos/metabolismo , Insulina/metabolismo , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Expressão Gênica , RNA Mensageiro/metabolismo , Morte Celular , Glucose/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo , Tristetraprolina/farmacologia
13.
Cell Rep ; 42(5): 112411, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37086408

RESUMO

Cellular metabolism is tightly regulated by growth factor signaling, which promotes metabolic rewiring to support growth and proliferation. While growth factor-induced transcriptional and post-translational modes of metabolic regulation have been well defined, whether post-transcriptional mechanisms impacting mRNA stability regulate this process is less clear. Here, we present the ZFP36/L1/L2 family of RNA-binding proteins and mRNA decay factors as key drivers of metabolic regulation downstream of acute growth factor signaling. We quantitatively catalog metabolic enzyme and nutrient transporter mRNAs directly bound by ZFP36 following growth factor stimulation-many of which encode rate-limiting steps in metabolic pathways. Further, we show that ZFP36 directly promotes the mRNA decay of Enolase 2 (Eno2), altering Eno2 protein expression and enzymatic activity, and provide evidence of a ZFP36/Eno2 axis during VEGF-stimulated developmental retinal angiogenesis. Thus, ZFP36-mediated mRNA decay serves as an important mode of metabolic regulation downstream of growth factor signaling within dynamic cell and tissue states.


Assuntos
Proteínas de Ligação a RNA , Transdução de Sinais , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Estabilidade de RNA/genética , Tristetraprolina/genética , Tristetraprolina/metabolismo
14.
Elife ; 122023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36961408

RESUMO

Tristetraprolin (TTP) is a critical negative immune regulator. It binds AU-rich elements in the untranslated-regions of many mRNAs encoding pro-inflammatory mediators, thereby accelerating their decay. A key but poorly understood mechanism of TTP regulation is its timely proteolytic removal: TTP is degraded by the proteasome through yet unidentified phosphorylation-controlled drivers. In this study, we set out to identify factors controlling TTP stability. Cellular assays showed that TTP is strongly lysine-ubiquitinated, which is required for its turnover. A genetic screen identified the ubiquitin E3 ligase HUWE1 as a strong regulator of TTP proteasomal degradation, which we found to control TTP stability indirectly by regulating its phosphorylation. Pharmacological assessment of multiple kinases revealed that HUWE1-regulated TTP phosphorylation and stability was independent of the previously characterized effects of MAPK-mediated S52/S178 phosphorylation. HUWE1 function was dependent on phosphatase and E3 ligase binding sites identified in the TTP C-terminus. Our findings indicate that while phosphorylation of S52/S178 is critical for TTP stabilization at earlier times after pro-inflammatory stimulation, phosphorylation of the TTP C-terminus controls its stability at later stages.


Assuntos
Tristetraprolina , Ubiquitina-Proteína Ligases , Fosforilação , Tristetraprolina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteólise , Ubiquitina/metabolismo , Estabilidade de RNA/genética
15.
PeerJ ; 11: e14776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846448

RESUMO

CCCH-type zinc figure proteins (ZFP) are small cellular proteins that are structurally maintained by zinc ions. Zinc ions coordinate the protein structure in a tetrahedral geometry by binding to cystine-cystine or cysteines-histidine amino acids. ZFP's unique structure enables it to interact with a wide variety of molecules including RNA; thus, ZFP modulates several cellular processes including the host immune response and virus replication. CCCH-type ZFPs have shown their antiviral efficacy against several DNA and RNA viruses. However, their role in the human coronavirus is little explored. We hypothesized that ZFP36L1 also suppresses the human coronavirus. To test our hypothesis, we used OC43 human coronavirus (HCoV) strain in our study. We overexpressed and knockdown ZFP36L1 in HCT-8 cells using lentivirus transduction. Wild type, ZFP36L1 overexpressed, and ZFP36L1 knockdown cells were each infected with HCoV-OC43, and the virus titer in each cell line was measured over 96 hours post-infection (p.i.). Our results show that HCoV-OC43 replication was significantly reduced with ZFP36L1 overexpression while ZFP36L1 knockdown significantly enhanced virus replication. ZFP36L1 knockdown HCT-8 cells started producing infectious virus at 48 hours p.i. which was an earlier timepoint as compared to wild -type and ZFP36L1 overexpressed cells. Wild-type and ZFP36L1 overexpressed HCT-8 cells started producing infectious virus at 72 hours p.i. Overall, the current study showed that overexpression of ZFP36L1 suppressed human coronavirus (OC43) production.


Assuntos
Coronavirus Humano OC43 , Humanos , Coronavirus Humano OC43/genética , Cistina , Linhagem Celular , Replicação Viral/genética , Fator 1 de Resposta a Butirato , Tristetraprolina
16.
Comb Chem High Throughput Screen ; 26(4): 838-847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35652405

RESUMO

AIM: In this study, we aimed to investigate whether resveratrol has anti-inflammatory effects on LPS-induced ALI via TTP enhancement. BACKGROUND: Acute lung injury (ALI) is a syndrome of diffuse infammatory lung injury with increased pulmonary edema and the rapid onset of hypoxemic respiratory failure. Resveratrol is a stilbenoid, a form of natural phenol, and a phytoalexin produced by a variety of plants in reaction to injury or when they are attacked by pathogens like bacteria or fungi. Resveratrol exhibits a potent antiinflammatory effect in LPS-induced ALI, while the underlying mechanisms remain elusive. OBJECTIVE: Tristetraprolin (TTP) is a RNA binding protein that is an important endogenous inhibitor of inflammation. The objective of the present study is to investigate whether resveratrol has anti- inflammatory effects on LPS-induced ALI via TTP enhancement. METHODS: Forty male C57BL/6 mice were randomly assigned to four groups and intratracheally instilled with 5 mg/kg lipopolysaccharide (LPS) to induce ALI. RESULTS: LPS-induced lung pathological damage, lung edema, and neutrophil infiltration were reduced by resveratrol pretreatment. Furthermore, resveratrol inhibited the LPS-induced rise in TNF- α, IL-1ß and IL-6 levels in BAL fluids. In the LPS-challenged mouse's lung tissue, resveratrol clearly boosted sirtuin1 (SIRT1) and TTP protein expression, while also increasing TTP expression while reducing proinflammatory cytokines. EX527, on the other hand, reversed resveratrol's effects. CONCLUSION: According to our findings, resveratrol attenuated pulmonary inflammation and lung injury in mice with LPS­induced ALI, at least partly correlated with promoting the activation of SIRT1/TTP signaling pathway, highlighting these pathways as potential targets for intervention in LPS -induced lung injury.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Camundongos , Animais , Resveratrol/farmacologia , Lipopolissacarídeos/toxicidade , Tristetraprolina/metabolismo , Tristetraprolina/farmacologia , Sirtuína 1/metabolismo , Sirtuína 1/farmacologia , Camundongos Endogâmicos C57BL , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Fator de Necrose Tumoral alfa/metabolismo
17.
J Biol Inorg Chem ; 28(1): 85-100, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36478265

RESUMO

Tristetraprolin (TTP) is a nonclassical CCCH zinc finger (ZF) that plays a crucial role in regulating inflammation. TTP regulates cytokine mRNAs by specific binding of its two conserved ZF domains (CysX8CysX5CysX3His) to adenylate-uridylate-rich sequences (AREs) at the 3'-untranslated region, leading to degradation of the RNA. Dysregulation of TTP in animal models has demonstrated several cytokine-related syndromes, including chronic inflammation and autoimmune disorders. Exposure to Pb(II), a prevalent environmental toxin, is known to contribute to similar pathologies, in part by disruption of and/or competition with cysteine-rich metalloproteins. TTP's role during stress as a ubiquitous translational regulator of cell signaling (and dysfunction), which may underpin various phenotypes of Pb(II) toxicity, highlights the importance of understanding the interaction between TTP and Pb(II). The impact of Pb(II) binding on TTP's fold and RNA-binding function was analyzed via UV-Vis spectroscopy, circular dichroism, X-ray absorption spectroscopy, nuclear magnetic resonance spectroscopy, and fluorescence anisotropy. A construct containing the two ZF domains of TTP (TTP-2D) bound to Pb(II) with nanomolar affinity and exhibited a different geometry and fold in comparison to Zn2-TTP-2D. Despite the altered secondary structure, Pb(II)-substituted TTP-2D bound a canonical ARE sequence more selectively than Zn2-TTP-2D. Taken together, these data suggest that Pb(II) may interfere with proper TTP regulation and hinder the cell's ability to respond to inflammation.


Assuntos
Chumbo , Tristetraprolina , Animais , Tristetraprolina/genética , Tristetraprolina/química , Tristetraprolina/metabolismo , Dedos de Zinco , RNA , Citocinas , Inflamação
18.
Inflammation ; 46(2): 700-717, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36422840

RESUMO

LncRNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) was found to be upregulated in plasma of patients with bronchial asthma. This study aimed to explore the roles and mechanisms of CDKN2B-AS1 in childhood asthma. We found that CDKN2B-AS1 was upregulated and zinc finger protein 36 (ZFP36) mRNA was downregulated in blood samples of children with asthma compared with healthy controls as measured by RT-qPCR. Human bronchial epithelial cell line BEAS-2B was treated with LPS to induce inflammation model. Small interfering RNA against CDKN2B-AS1 (si-CDKN2B-AS1) was transfected into LPS-treated BEAS-2B cells, and we observed that CDKN2B-AS1 silencing increased cell viability and inhibited apoptosis and inflammation cytokine levels in LPS-treated BEAS-2B cells. Methylation-specific PCR, ChIP, and RIP assays indicated that CDKN2B-AS1 inhibited ZFP36 expression by recruiting DNMT1 to promote ZFP36 promoter methylation. Co-immunoprecipitation (Co-IP) assay verified the interaction between ZFP36 and nuclear receptor subfamily 4 group A member 1 (NR4A1) proteins. Then rescue experiments revealed that ZFP36 knockdown reversed the effects of CDKN2B-AS1 silencing on BEAS-2B cell functions. ZFP36 overexpression facilitated apoptosis, inflammation, and p-p65 expression in BEAS-2B cells, while NR4A1 knockdown reversed these effects. Additionally, CDKN2B-AS1 silencing alleviated airway hyperresponsiveness and inflammation in ovalbumin (OVA)-induced asthma mice. In conclusion, silencing lncRNA CDKN2B-AS1 enhances BEAS-2B cell viability, reduces apoptosis and inflammation in vitro, and alleviated asthma symptoms in OVA-induced asthma mice in vivo through inhibiting ZFP36 promoter methylation and NR4A1-mediated NF-κB signaling pathway.


Assuntos
Asma , RNA Longo não Codificante , Criança , Humanos , Camundongos , Animais , RNA Longo não Codificante/metabolismo , Tristetraprolina/metabolismo , Metilação , Lipopolissacarídeos/metabolismo , Asma/induzido quimicamente , Asma/genética , Inflamação , Proliferação de Células/genética , Linhagem Celular Tumoral , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo
19.
Neuroscience ; 509: 157-172, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435477

RESUMO

ß-hydroxybutyrate (BHB) is one of main component of ketone body, which plays an important protective role in various tissues and organs. Whereas, its exact regulatory roles and mechanisms in Parkinson's disease (PD) have not been full elucidated. In this study, SN4741 cells and C57BL/6 mice were treated with 1-methyl-4-phenylpyridinium ion (MPP+)/1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to establish the PD model in vitro and in vivo. Cell viability and damage to dopaminergic neurons were measured by cell counting kit 8, Calcein-AM/PI staining, terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling and hematoxylin & eosin staining. Corresponding assay kits and BODIPY 581/591 C11 probe evaluated oxidative stress and intracellular iron levels. Western blot examined the ferroptosis-related proteins. MPTP/MPP+-treatment reduced cell viability but triggered oxidative stress and ferroptosis in SNA4741 cells and brain tissues of mice. However, these effects were dramatically reversed by BHB and Fer-1 treatment. Mechanistically, Zinc finger protein 36 (ZFP36) was a target of BHB, and its depletion could reverse the anti-oxidative stress and anti-ferroptosis roles of BHB. Moreover, ZFP36 could directly bound to acyl-CoA synthetase long-chain family member 4 (ACSL4) mRNA to decay its expression, thus negatively modulating ACSL4-mediated oxidative stress and ferroptosis. Summary, BHB alleviated oxidative stress and ferroptosis of dopaminergic neurons in PD via modulating ZFP36/ACSL4 axis, which provided some new understanding for PD prevention and treatment.


Assuntos
Neurônios Dopaminérgicos , Doença de Parkinson , Camundongos , Animais , Ácido 3-Hidroxibutírico/farmacologia , Neurônios Dopaminérgicos/metabolismo , Tristetraprolina/metabolismo , Camundongos Endogâmicos C57BL , Doença de Parkinson/metabolismo , 1-Metil-4-fenilpiridínio/toxicidade , Corpos Cetônicos/metabolismo , Ligases/metabolismo
20.
Kaohsiung J Med Sci ; 39(3): 254-265, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36524461

RESUMO

Hyperglycemia is the most important factor leading to the complications of type 2 diabetes mellitus (T2DM). The primary condition for the treatment of T2DM is to change the glucose and lipid metabolism disorders in the liver and other insulin-sensitive tissues. The current study aims to unearth the potential molecular mechanism of inhibiting liver gluconeogenesis to provide a new theoretical basis for the treatment of T2DM. High glucose (HG) induction of HepG2 cells followed by treatment with sequence-similar family 3 member D (FAM3D). Dual specificity phosphatases 1 (DUSP1), zinc finger protein 36 (ZFP36), salt-induced kinase 1 (SIK1), p-SIK1, posphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) gene and protein expression level were detected by quantitative real-time polymerase chain reaction and western blot. The PEPCK and G6Pase activities were detected by enzyme linked immunosorbent assay. Glucose production assay to determine glucose content. The RNA binding protein immunoprecipitation assay was used to detect the binding of ZFP36 to SIK1. FAM3D facilitated the expression of DUSP1 but suppressed the expression of gluconeogenesis-related factors in an HG environment. The expression of ZFP36 was up-regulated in an HG environment. ZFP36 could reverse the inhibition of gluconeogenesis caused by FAM3D. HG-induced upregulation of ZFP36 was downregulated by overexpression of DUSP1. ZFP36 bound to SIK1, and downregulation of ZFP36 promoted SIK1 expression and inhibits gluconeogenesis. Our study demonstrated FAM3D inhibited gluconeogenesis through the DUSP1/ZFP36/SIK1 axis in an HG environment, which provided a new theoretical basis for exploring the pathogenesis and treatment strategy of T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Gluconeogênese , Humanos , Gluconeogênese/genética , Tristetraprolina/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Fígado/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Fosfatase 1 de Especificidade Dupla/genética , Fosfatase 1 de Especificidade Dupla/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Citocinas/metabolismo
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