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1.
J Biol Chem ; 300(5): 107249, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556084

RESUMO

Tripartite-motif protein-56 (TRIM56) positively regulates the induction of type I interferon response via the TLR3 pathway by enhancing IRF3 activation and depends on its C-terminal residues 621-750 for interacting with the adaptor TRIF. However, the precise underlying mechanism and detailed TRIM56 determinants remain unclear. Herein, we show ectopic expression of murine TRIM56 also enhances TLR3-dependent interferon-ß promoter activation, suggesting functional conservation. We found that endogenous TRIM56 and TRIF formed a complex early (0.5-2 h) after poly-I:C stimulation and that TRIM56 overexpression also promoted activation of NF-κB by poly-I:C but not that by TNF-α or IL-1ß, consistent with a specific effect on TRIF prior to the bifurcation of NF-κB and IRF3. Using transient transfection and Tet-regulated cell lines expressing various TRIM56 mutants, we demonstrated the Coiled-coil domain and a segment spanning residues ∼434-610, but not the B-box or residues 355-433, were required for TRIM56 augmentation of TLR3 signaling. Moreover, alanine substitution at each putative phosphorylation site, Ser471, Ser475, and Ser710, abrogated TRIM56 function. Concordantly, mutants bearing Ser471Ala, Ser475Ala, or Ser710Ala, or lacking the Coiled-coil domain, all lost the capacity to enhance poly-I:C-induced establishment of an antiviral state. Furthermore, the Ser710Ala mutation disrupted the TRIM56-TRIF association. Using phospho-specific antibodies, we detected biphasic phosphorylation of TRIM56 at Ser471 and Ser475 following TLR3 stimulation, with the early phase occurring at ∼0.5 to 1 h, prior to IRF3 phosphorylation. Together, these data reveal novel molecular details critical for the TRIM56 augmentation of TLR3-dependent antiviral response and highlight important roles for TRIM56 scaffolding and phosphorylation.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Imunidade Inata , Receptor 3 Toll-Like , Proteínas com Motivo Tripartido , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/imunologia , Células HEK293 , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , NF-kappa B/metabolismo , Fosforilação , Poli I-C/farmacologia , Domínios Proteicos , Transdução de Sinais , Receptor 3 Toll-Like/metabolismo , Receptor 3 Toll-Like/genética , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
2.
Mol Psychiatry ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459194

RESUMO

Cognitive and behavioral rigidity are observed in various psychiatric diseases, including in autism spectrum disorder (ASD). However, the underlying mechanism remains to be elucidated. In this study, we found that neuroligin-3 (NL3) R451C knockin mouse model of autism (KI mice) exhibited deficits in behavioral flexibility in choice selection tasks. Single-unit recording of medium spiny neuron (MSN) activity in the nucleus accumbens (NAc) revealed altered encoding of decision-related cue and impaired updating of choice anticipation in KI mice. Additionally, fiber photometry demonstrated significant disruption in dynamic mesolimbic dopamine (DA) signaling for reward prediction errors (RPEs), along with reduced activity in medial prefrontal cortex (mPFC) neurons projecting to the NAc in KI mice. Interestingly, NL3 re-expression in the mPFC, but not in the NAc, rescued the deficit of flexible behaviors and simultaneously restored NAc-MSN encoding, DA dynamics, and mPFC-NAc output in KI mice. Taken together, this study reveals the frontostriatal circuit dysfunction underlying cognitive inflexibility and establishes a critical role of the mPFC NL3 deficiency in this deficit in KI mice. Therefore, these findings provide new insights into the mechanisms of cognitive and behavioral inflexibility and potential intervention strategies.

3.
Brain ; 147(6): 2169-2184, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38662500

RESUMO

Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in 5XFAD mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissues from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2) and the excitatory NMDA and AMPA type glutamate receptors. We performed patch-clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and decreased GABAA receptor subunit expression, as well as increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced amyloid-ß pathology and cognitive deficits, could also reverse elevations of the NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with US Food and Drug Administration-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.


Assuntos
Doença de Alzheimer , Camundongos Transgênicos , Convulsões , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Convulsões/metabolismo , Convulsões/fisiopatologia , Camundongos , Masculino , Humanos , Feminino , Pentilenotetrazol/toxicidade , Idoso , Modelos Animais de Doenças , Excitação Neurológica/efeitos dos fármacos , Idoso de 80 Anos ou mais
4.
Eur J Neurosci ; 59(12): 3337-3352, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38654472

RESUMO

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is caused by a loss-of-function mutation in CDKL5 gene, encoding a serine-threonine kinase highly expressed in the brain. CDD manifests with early-onset epilepsy, autism, motor impairment and severe intellectual disability. While there are no known treatments for CDD, the use of cannabidiol has recently been introduced into clinical practice for neurodevelopmental disorders. Given the increased clinical utilization of cannabidiol, we examined its efficacy in the CDKL5R59X knock-in (R59X) mice, a CDD model based on a human mutation that exhibits both lifelong seizure susceptibility and behavioural deficits. We found that cannabidiol pre-treatment rescued the increased seizure susceptibility in response to the chemoconvulsant pentylenetetrazol (PTZ), attenuated working memory and long-term memory impairments, and rescued social deficits in adult R59X mice. To elucidate a potential mechanism, we compared the developmental hippocampal and cortical expression of common endocannabinoid (eCB) targets in R59X mice and their wild-type littermates, including cannabinoid type 1 receptor (CB1R), transient receptor potential vanilloid type 1 (TRPV1) and 2 (TRPV2), G-coupled protein receptor 55 (GPR55) and adenosine receptor 1 (A1R). Many of these eCB targets were developmentally regulated in both R59X and wild-type mice. In addition, adult R59X mice demonstrated significantly decreased expression of CB1R and TRPV1 in the hippocampus, and TRPV2 in the cortex, while TRPV1 was increased in the cortex. These findings support the potential for dysregulation of eCB signalling as a plausible mechanism and therapeutic target in CDD, given the efficacy of cannabidiol to attenuate hyperexcitability and behavioural deficits in this disorder.


Assuntos
Canabidiol , Proteínas Serina-Treonina Quinases , Convulsões , Animais , Canabidiol/farmacologia , Convulsões/tratamento farmacológico , Convulsões/genética , Convulsões/metabolismo , Camundongos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Síndromes Epilépticas/genética , Síndromes Epilépticas/tratamento farmacológico , Pentilenotetrazol , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Modelos Animais de Doenças , Técnicas de Introdução de Genes/métodos , Masculino , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Endocanabinoides/metabolismo , Comportamento Animal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Espasmos Infantis , Receptores de Canabinoides
5.
Biochem Biophys Res Commun ; 699: 149496, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38290175

RESUMO

BACKGROUND: Peripheral nerve injury (PNI) presents a significant clinical challenge, leading to enduring sensory-motor impairments. While mesenchymal stem cell (MSC)-based therapy holds promise for PNI treatment, enhancing its neurotrophic effects remains crucial. Platelet-rich plasma-derived exosomes (PRP-Exo), rich in bioactive molecules for intercellular communication, offer potential for modulating cellular biological activity. METHODS: PRP-Exo was isolated, and its impact on MSC viability was evaluated. The effects of PRP-Exo-treated MSCs (MSCPExo) on Schwann cells (SCs) from injured sciatic nerves and human umbilical vein endothelial cells (HUVECs) were assessed. Furthermore, the conditioned medium from MSCPExo (MSCPExo-CM) was analyzed using a cytokine array and validated through ELISA and Western blot. RESULTS: PRP-Exo enhanced MSC viability. Coculturing MSCPExo with SCs ameliorated apoptosis and promoted SC proliferation following PNI. Similarly, MSCPExo-CM exhibited pro-proliferative, migratory, and angiogenic effects. Cytokine array analysis identified 440 proteins in the MSCPExo secretome, with 155 showing upregulation and 6 showing downregulation, many demonstrating potent pro-regenerative properties. ELISA confirmed the enrichment of several angiotrophic and neurotrophic factors. Additionally, Western blot analysis revealed the activation of the PI3K/Akt signaling pathway in MSCPExo. CONCLUSION: Preconditioning MSCs with PRP-Exo enhanced the paracrine function, particularly augmenting neurotrophic and pro-angiogenic secretions, demonstrating an improved potential for neural repair.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Plasma Rico em Plaquetas , Humanos , Exossomos/metabolismo , Células Endoteliais , Fosfatidilinositol 3-Quinases/metabolismo , Citocinas/metabolismo , Regeneração Nervosa
6.
BMC Cancer ; 24(1): 582, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741069

RESUMO

BACKGROUND: Local recurrence after surgery and radiochemotherapy seriously affects the prognosis of locally advanced rectal cancer (LARC) patients. Studies on molecular markers related to the radiochemotherapy sensitivity of cancers have been widely carried out, which might provide valued information for clinicians to carry out individual treatment. AIM: To find potential biomarkers of tumors for predicting postoperative recurrence. METHODS: In this study, LARC patients undergoing surgery and concurrent radiochemotherapy were enrolled. We focused on clinicopathological factors and PTEN, SIRT1, p-4E-BP1, and pS6 protein expression assessed by immunohistochemistry in 73 rectal cancer patients with local recurrence and 76 patients without local recurrence. RESULTS: The expression of PTEN was higher, while the expression of p-4E-BP1 was lower in patients without local recurrence than in patients with local recurrence. Moreover, TNM stage, lymphatic vessel invasion (LVI), PTEN and p-4E-BP1 might be independent risk factors for local recurrence after LARC surgery combined with concurrent radiochemotherapy. CONCLUSIONS: This study suggests that PTEN and p-4E-BP1 might be potential biomarkers for prognostic prediction and therapeutic targets for LARC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Biomarcadores Tumorais , Proteínas de Ciclo Celular , Quimiorradioterapia , Recidiva Local de Neoplasia , PTEN Fosfo-Hidrolase , Neoplasias Retais , Humanos , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Neoplasias Retais/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Quimiorradioterapia/métodos , Biomarcadores Tumorais/metabolismo , Idoso , Prognóstico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fosfoproteínas/metabolismo , Adulto , Estadiamento de Neoplasias
7.
Langmuir ; 40(24): 12526-12538, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38836644

RESUMO

l-cysteine, as an eco-friendly and nontoxic corrosion inhibitor, was directly covalently linked to the carbon/carbon double bonds of the GO flakes by a thiol-ene click reaction to avoid decreasing the number of hydrophilic oxygen-containing polar functionalities. The corrosion inhibition performances of Cys-GO toward Q235 steel (QS) in diluted hydrochloric acid were studied by electrochemical methods. The corrosion was a charge transfer-controlled process, and Cys-GO manifested as a mixed-type corrosion inhibitor. The corrosion inhibition efficiency (η) for QS showed a first-increase-and-then-decrease trend with increasing Cys-GO concentrations. The optimum concentration of Cys-GO was 15 mg L-1, and the according η value was up to 90%. The Cys-GO adsorbed on the QS surface to form a protective barrier was responsible for the efficient corrosion inhibition. Langmuir adsorption isotherm model was fitted well with the experiment data, indicating a monolayer adsorption. Furthermore, the coordinate covalent bonds, π-back-donation effect, and electrostatic attraction were responsible for the Cys-GO adsorption on the QS surface.

8.
Lancet Oncol ; 24(10): 1134-1146, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797632

RESUMO

BACKGROUND: Immune checkpoint inhibitors targeting PD-1 or CTLA-4 individually have shown substantial clinical benefits in the treatment of malignancies. We aimed to assess the safety and antitumour activity of cadonilimab monotherapy, a bispecific PD-1/CTLA-4 antibody, in patients with advanced solid tumours. METHODS: This multicentre, open-label, phase 1b/2 trial was conducted across 30 hospitals in China. Patients aged 18 years or older with histologically or cytologically confirmed, unresectable advanced solid tumours, unsuccessful completion of at least one previous systemic therapy, and an Eastern Cooperative Oncology Group performance status of 0 or 1 were eligible for inclusion. Patients who had previously received anti-PD-1, anti-PD-L1, or anti-CTLA-4 treatment were not eligible for inclusion. In the dose escalation phase of phase 1b, patients received intravenous cadonilimab at 6 mg/kg and 10 mg/kg every 2 weeks. In the dose expansion phase of phase 1b, cadonilimab at 6 mg/kg and a fixed dose of 450 mg were given intravenously every 2 weeks. In phase 2, cadonilimab at 6 mg/kg was administered intravenously every 2 weeks in three cohorts: patients with cervical cancer, oesophageal squamous cell carcinoma, and hepatocellular carcinoma. The primary endpoints were the safety of cadonilimab in phase 1b and objective response rate in phase 2, based on the Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. The safety analysis was done in all patients who received at least one dose of cadonilimab. Antitumour activity was assessed in the full analysis set for the cervical cancer cohort, and in all patients with measurable disease at baseline and who received at least one dose of cadonilimab in the oesophageal squamous cell carcinoma and hepatocellular carcinoma cohorts. The study is registered on ClinicalTrial.gov, NCT03852251, and closed to new participants; follow-up has been completed. FINDINGS: Between Jan 18, 2019, and Jan 8, 2021, 240 patients (83 [43 male and 40 female] in phase 1b and 157 in phase 2) were enrolled. Phase 2 enrolled 111 female patients with cervical cancer, 22 patients with oesophageal squamous cell carcinoma (15 male and seven female), and 24 patients with hepatocellular carcinoma (17 male and seven female). During dose escalation, no dose-limiting toxicities occurred. Grade 3-4 treatment-related adverse events occurred in 67 (28%) of 240 patients; the most frequent grade 3 or worse treatment-related adverse events were anaemia (seven [3%]), increased lipase (four [2%]), decreased bodyweight (three [1%]), decreased appetite (four [2%]), decreased neutrophil count (three [1%]), and infusion-related reaction (two [1%]). 17 (7%) patients discontinued treatment due to treatment-related adverse events. 54 (23%) of 240 patients reported serious treatment-related adverse events, including five patients who died (one due to myocardial infarction; cause unknown for four). In phase 2, in the cervical cancer cohort, with a median follow-up of 14·6 months (IQR 13·1-17·5), the objective response rate was 32·3% (32 of 99; 95% CI 23·3-42·5). In the oesophageal squamous cell carcinoma cohort, with a median follow-up of 17·9 months (IQR 4·0-15·1), the objective response rate was 18·2% (four of 22; 95% CI 5·2-40·3). In the hepatocellular carcinoma cohort, with a median follow-up of 19·6 months (IQR 8·7-19·8), the objective response rate was 16·7% (four of 24; 95% CI 4·7-37·4). INTERPRETATION: Cadonilimab showed an encouraging tumour response rate, with a manageable safety profile, suggesting the potential of cadonilimab for the treatment of advanced solid tumours. FUNDING: Akeso Biopharma. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Hepatocelular , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias Hepáticas , Neoplasias do Colo do Útero , Humanos , Masculino , Feminino , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Antígeno CTLA-4 , Receptor de Morte Celular Programada 1 , Empatia , Anticorpos Monoclonais Humanizados , Antineoplásicos Imunológicos/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Hepáticas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
9.
J Virol ; 96(10): e0002722, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35481781

RESUMO

Noncanonical NF-κB signaling is activated in B cells via the tumor necrosis factor (TNF) receptor superfamily members CD40, lymphotoxin ß receptor (LTßR), and B-cell-activating factor receptor (BAFF-R). The noncanonical pathway is required at multiple stages of B cell maturation and differentiation, including the germinal center reaction. However, the role of this pathway in gammaherpesvirus latency is not well understood. Murine gammaherpesvirus 68 (MHV68) is a genetically tractable system used to define pathogenic determinants. Mice lacking the BAFF-R exhibit defects in splenic follicle formation and are greatly reduced for MHV68 latency. We report a novel approach to disrupt noncanonical NF-κB signaling exclusively in cells infected with MHV68. We engineered a recombinant virus that expresses a dominant negative form of IκB kinase α (IKKα), named IKKα-SA, with S176A and S180A mutations that prevent phosphorylation by NF-κB-inducing kinase (NIK). We controlled for the transgene insertion by introducing two all-frame stop codons into the IKKα-SA gene. The IKKα-SA mutant but not the IKKα-SA.STOP control virus impaired LTßR-mediated activation of NF-κB p52 upon fibroblast infection. IKKα-SA expression did not impact replication in primary fibroblasts or in the lungs of mice following intranasal inoculation. However, the IKKα-SA mutant was severely defective in the colonization of the spleen and in the establishment of latency compared to the IKKα-SA.STOP control and wild-type (WT) MHV68 at 16 days postinfection (dpi). Reactivation was undetectable in splenocytes infected with the IKKα-SA mutant, but reactivation in peritoneal cells was not impacted by IKKα-SA. Taken together, the noncanonical NF-κB signaling pathway is essential for the establishment of latency in the secondary lymphoid organs of mice infected with the murine gammaherpesvirus pathogen MHV68. IMPORTANCE The latency programs of the human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) are associated with B cell lymphomas. It is critical to understand the signaling pathways that are used by gammaherpesviruses to establish and maintain latency in primary B cells. We used a novel approach to block noncanonical NF-κB signaling only in the infected cells of mice. We generated a recombinant virus that expresses a dominant negative mutant of IKKα that is nonresponsive to upstream activation. Latency was reduced in a route- and cell type-dependent manner in mice infected with this recombinant virus. These findings identify a significant role for the noncanonical NF-κB signaling pathway that might provide a novel target to prevent latent infection of B cells with oncogenic gammaherpesviruses.


Assuntos
Infecções por Herpesviridae , Quinase I-kappa B , NF-kappa B , Rhadinovirus , Latência Viral , Animais , Infecções por Herpesviridae/metabolismo , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Rhadinovirus/fisiologia , Transdução de Sinais , Latência Viral/genética
10.
J Virol ; 96(17): e0102822, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35969079

RESUMO

Herpesviruses establish latency to ensure permanent residence in their hosts. Upon entry into a cell, these viruses are rapidly silenced by the host, thereby limiting the destructive viral lytic phase while allowing the virus to hide from the immune system. Notably, although the establishment of latency by the oncogenic herpesvirus Epstein-Barr virus (EBV) requires the expression of viral latency genes, latency can be maintained with a negligible expression of viral genes. Indeed, in several herpesviruses, the host DNA sensor IFI16 facilitated latency via H3K9me3 heterochromatinization. This silencing mark is typically imposed by the constitutive heterochromatin machinery (HCM). The HCM, in an antiviral role, also silences the lytic phase of EBV and other herpes viruses. We investigated if IFI16 restricted EBV lytic activation by partnering with the HCM and found that IFI16 interacted with core components of the HCM, including the KRAB-associated protein 1 (KAP1) and the site-specific DNA binding KRAB-ZFP SZF1. This partnership silenced the EBV lytic switch protein ZEBRA, encoded by the BZLF1 gene, thereby favoring viral latency. Indeed, IFI16 contributed to H3K9 trimethylation at lytic genes of all kinetic classes. In defining topology, we found that IFI16 coenriched with KAP1 at the BZLF1 promoter, and while IFI16 and SZF1 were each adjacent to KAP1 in latent cells, IFI16 and SZF1 were not. Importantly, we also found that disruption of latency involved rapid downregulation of IFI16 transcription. These findings revealed a previously unknown partnership between IFI16 and the core HCM that supports EBV latency via antiviral heterochromatic silencing. IMPORTANCE The interferon-gamma inducible protein 16 (IFI16) is a nuclear DNA sensor that mediates antiviral responses by activating the inflammasome, triggering an interferon response, and silencing lytic genes of herpesviruses. The last, which helps maintain latency of the oncoherpesvirus Epstein-Barr virus (EBV), is accomplished via H3K9me3 heterochromatinization through unknown mechanisms. Here, we report that IFI16 physically partners with the core constitutive heterochromatin machinery to silence the key EBV lytic switch protein, thereby ensuring continued viral latency in B lymphocytes. We also find that disruption of latency involves rapid transcriptional downregulation of IFI16. These findings point to hitherto unknown physical and functional partnerships between a well-known antiviral mechanism and the core components of the constitutive heterochromatin machinery.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Proteínas Nucleares , Fosfoproteínas , Proteína 28 com Motivo Tripartido , Latência Viral , Linhagem Celular Tumoral , Infecções por Vírus Epstein-Barr/genética , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Heterocromatina/genética , Heterocromatina/metabolismo , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Proteína 28 com Motivo Tripartido/genética , Proteína 28 com Motivo Tripartido/metabolismo , Ativação Viral
11.
J Transl Med ; 21(1): 323, 2023 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-37179292

RESUMO

BACKGROUND: Pericyte-myofibroblast transition (PMT) has been confirmed to contribute to renal fibrosis in several kidney diseases, and transforming growth factor-ß1 (TGF-ß1) is a well-known cytokine that drives PMT. However, the underlying mechanism has not been fully established, and little is known about the associated metabolic changes. METHODS: Bioinformatics analysis was used to identify transcriptomic changes during PMT. PDGFRß + pericytes were isolated using MACS, and an in vitro model of PMT was induced by 5 ng/ml TGF-ß1. Metabolites were analyzed by ultraperformance liquid chromatography (UPLC) and tandem mass spectrometry (MS). 2-Deoxyglucose (2-DG) was used to inhibit glycolysis via its actions on hexokinase (HK). The hexokinase II (HKII) plasmid was transfected into pericytes for HKII overexpression. LY294002 or rapamycin was used to inhibit the PI3K-Akt-mTOR pathway for mechanistic exploration. RESULTS: An increase in carbon metabolism during PMT was detected through bioinformatics and metabolomics analysis. We first detected increased levels of glycolysis and HKII expression in pericytes after stimulation with TGF-ß1 for 48 h, accompanied by increased expression of α-SMA, vimentin and desmin. Transdifferentiation was blunted when pericytes were pretreated with 2-DG, an inhibitor of glycolysis. The phosphorylation levels of PI3K, Akt and mTOR were elevated during PMT, and after inhibition of the PI3K-Akt-mTOR pathway with LY294002 or rapamycin, glycolysis in the TGF-ß1-treated pericytes was decreased. Moreover, PMT and HKII transcription and activity were blunted, but the plasmid-mediated overexpression of HKII rescued PMT inhibition. CONCLUSIONS: The expression and activity of HKII as well as the level of glycolysis were increased during PMT. Moreover, the PI3K-Akt-mTOR pathway regulates PMT by increasing glycolysis through HKII regulation.


Assuntos
Transdução de Sinais , Fator de Crescimento Transformador beta1 , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hexoquinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Pericitos/metabolismo , Miofibroblastos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Sirolimo , Glicólise
12.
J Transl Med ; 21(1): 653, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37740179

RESUMO

BACKGROUND: Kaposi sarcoma (KS) is a multicentric tumor caused by Kaposi sarcoma herpesvirus (KSHV) that leads to morbidity and mortality among people with HIV worldwide. KS commonly involves the skin but can occur in the gastrointestinal tract (GI) in severe cases. METHODS: RNA sequencing was used to compare the cellular and KSHV gene expression signatures of skin and GI KS lesions in 44 paired samples from 19 participants with KS alone or with concurrent KSHV-associated diseases. Analyses of KSHV expression from KS lesions identified transcriptionally active areas of the viral genome. RESULTS: The transcript of an essential viral lytic gene, ORF75, was detected in 91% of KS lesions. Analyses of host genes identified 370 differentially expressed genes (DEGs) unique to skin KS and 58 DEGs unique to GI KS lesions as compared to normal tissue. Interleukin (IL)-6 and IL-10 gene expression were higher in skin lesions as compared to normal skin but not in GI KS lesions. Twenty-six cellular genes were differentially expressed in both skin and GI KS tissues: these included Fms-related tyrosine kinase 4 (FLT4), encoding an angiogenic receptor, and Stanniocalcin 1 (STC1), a secreted glycoprotein. FLT4 and STC1 were further investigated in functional studies using primary lymphatic endothelial cells (LECs). In these models, KSHV infection of LECs led to increased tubule formation that was impaired upon knock-down of STC1 or FLT4. CONCLUSIONS: This study of transcriptional profiling of KS tissue provides novel insights into the characteristics and pathogenesis of this unique virus-driven neoplasm.


Assuntos
Herpesvirus Humano 8 , Sarcoma de Kaposi , Neoplasias Cutâneas , Humanos , Sarcoma de Kaposi/genética , Células Endoteliais , Herpesvirus Humano 8/genética , Pele , Interleucina-6
13.
PLoS Pathog ; 17(3): e1009447, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33730092

RESUMO

Krüppel-associated box-domain zinc finger protein (KRAB-ZFP) transcriptional repressors recruit TRIM28/KAP1 to heterochromatinize the mammalian genome while also guarding the host by silencing invading foreign genomes. However, how a KRAB-ZFP recognizes target sequences in the natural context of its own or foreign genomes is unclear. Our studies on B-lymphocytes permanently harboring the cancer-causing Epstein-Barr virus (EBV) have shown that SZF1, a KRAB-ZFP, binds to several lytic/replicative phase genes to silence them, thereby promoting the latent/quiescent phase of the virus. As a result, unless SZF1 and its binding partners are displaced from target regions on the viral genome, EBV remains dormant, i.e. refractory to lytic phase-inducing triggers. As SZF1 also heterochromatinizes the cellular genome, we performed in situ footprint mapping on both viral and host genomes in physically separated B-lymphocytes bearing latent or replicative/active EBV genomes. By analyzing footprints, we learned that SZF1 recognizes the host genome through a repeat sequence-bearing motif near centromeres. Remarkably, SZF1 does not use this motif to recognize the EBV genome. Instead, it uses distinct binding sites that lack obvious similarities to each other or the above motif, to silence the viral genome. Virus mutagenesis studies show that these distinct binding sites are not only key to maintaining the established latent phase but also silencing the lytic phase in newly-infected cells, thus enabling the virus to establish latency and transform cells. Notably, these binding sites on the viral genome, when also present on the human genome, are not used by SZF1 to silence host genes during latency. This differential approach towards target site recognition may reflect a strategy by which the host silences and regulates genomes of persistent invaders without jeopardizing its own homeostasis.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Inativação Gênica/fisiologia , Proteínas Repressoras/metabolismo , Latência Viral/fisiologia , Linfócitos B/virologia , Herpesvirus Humano 4/genética , Heterocromatina/metabolismo , Humanos
14.
Opt Express ; 31(2): 890-906, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785136

RESUMO

The particle composition of suspended matter provides crucial information for a deeper understanding of marine biogeochemical processes and environmental changes. Particulate backscattering efficiency (Qbbe(λ)) is critical to understand particle composition, and a Qbbe(λ)-based model for classifying particle types was proposed. In this study, we evaluated the applicability of the Qbbe(λ)-based model to satellite observations in the shallow marginal Bohai and Yellow Seas. Spatiotemporal variations of the particle types and their potential driving factors were studied. The results showed that the Qbbe(λ) products generated from Moderate Resolution Imaging Spectroradiometer (MODIS) on the satellite Aqua agreed well with the in situ measured values, with determination coefficient, root mean square error, bias, and mean absolute percentage error of 0.76, 0.007, 16.5%, and 31.0%, respectively. This result verifies the satellite applicability of the Qbbe(λ)-based model. Based on long-term MODIS data, we observed evident spatiotemporal variations of the Qbbe(λ), from which distinct particle types were identified. Coastal waters were often dominated by minerals, with high Qbbe(λ) values, though their temporal changes were also observed. In contrast, waters in the offshore regions showed clear changes in particle types, which shifted from organic-dominated with low Qbbe(λ) levels in summer to mineral-dominated with high Qbbe(λ) values in winter. We also observed long-term increasing and decreasing trends in Qbbe(λ) in some regions, indicating a relative increase in the proportions of mineral and organic particles in the past decades, respectively. These spatiotemporal variations of Qbbe(λ) and particle types were probably attributed to sediment re-suspension related to water mixing driven by wind and tidal forcing, and to sediment load associated with river discharge. Overall, the findings of this study may provide valuable proxies for better studying marine biogeochemical processes, material exchanges, and sediment flux.

15.
Acta Pharmacol Sin ; 44(9): 1815-1825, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37055531

RESUMO

Damage to peritubular capillaries is a key process that contributes to acute kidney injury (AKI) progression. Vascular endothelial growth factor A (VEGFA) plays a critical role in maintaining the renal microvasculature. However, the physiological role of VEGFA in various AKI durations remains unclear. A severe unilateral ischemia‒reperfusion injury model was established to provide an overview of VEGFA expression and the peritubular microvascular density from acute to chronic injury in mouse kidneys. Therapeutic strategies involving early VEGFA supplementation protecting against acute injury and late anti-VEGFA treatment for fibrosis alleviation were analyzed. A proteomic analysis was conducted to determine the potential mechanism of renal fibrosis alleviation by anti-VEGFA. The results showed that two peaks of extraglomerular VEGFA expression were observed during AKI progression: one occurred at the early phase of AKI, and the other occurred during the transition to chronic kidney disease (CKD). Capillary rarefaction progressed despite the high expression of VEGFA at the CKD stage, and VEGFA was associated with interstitial fibrosis. Early VEGFA supplementation protected against renal injury by preserving microvessel structures and counteracting secondary tubular hypoxic insults, whereas late anti-VEGFA treatment attenuated renal fibrosis progression. The proteomic analysis highlighted an array of biological processes related to fibrosis alleviation by anti-VEGFA, which included regulation of supramolecular fiber organization, cell-matrix adhesion, fibroblast migration, and vasculogenesis. These findings establish the landscape of VEGFA expression and its dual roles during AKI progression, which provides the possibility for the orderly regulation of VEGFA to alleviate early acute injury and late fibrosis.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular , Proteômica , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Fibrose
16.
Chaos ; 33(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37097949

RESUMO

Physics-informed neural networks (PiNNs) recently emerged as a powerful solver for a large class of partial differential equations (PDEs) under various initial and boundary conditions. In this paper, we propose trapz-PiNNs, physics-informed neural networks incorporated with a modified trapezoidal rule recently developed for accurately evaluating fractional Laplacian and solve the space-fractional Fokker-Planck equations in 2D and 3D. We describe the modified trapezoidal rule in detail and verify the second-order accuracy. We demonstrate that trapz-PiNNs have high expressive power through predicting the solution with low L 2 relative error by a variety of numerical examples. We also use local metrics, such as point-wise absolute and relative errors, to analyze where it could be further improved. We present an effective method for improving the performance of trapz-PiNN on local metrics, provided that physical observations or high-fidelity simulation of the true solution are available. The trapz-PiNN is able to solve PDEs with fractional Laplacian with arbitrary α ∈ ( 0 , 2 ) and on rectangular domains. It also has the potential to be generalized into higher dimensions or other bounded domains.

17.
Int J Environ Health Res ; 33(7): 629-638, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35220835

RESUMO

Little concern has been paid to the relationship between temperature and varicella among adults. Daily meteorological data and varicella cases in Qingdao among adults from 1 January 2008 to 31 December 2019 were collected. A combination of quasi-Poisson generalized additive model (GAM) and distributed lag non-linear model (DLNM) was conducted to assess the temperature-lag-varicella relationship. We also estimated the lag-response curves for different temperatures and the exposure-response relationships for different lag days. The number of varicella cases was 10,296. Compared with the minimum-varicella temperature (25°C), we found the largest effect of temperature on varicella within 21 lag days was at 1°C (RR, 6.72; 95% CI, 2.90-15.57), and then the effect declined as the temperature increased. A similar trend of rising first and then falling was found in temperature-response curves for different lag days. A reverse U-shape lag pattern was found for different levels of temperatures. Temperature may affect varicella.


Assuntos
Varicela , Humanos , Adulto , Temperatura , Varicela/epidemiologia , China/epidemiologia
18.
Environ Geochem Health ; 45(7): 4203-4217, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36640213

RESUMO

Seasonal atmospheric particulate matter samples with different particle sizes (< 2.5 µm [PM2.5], 2.5-5 µm [PM2.5-5], 5-10 µm [PM5-10], and 10-100 µm [PM10-100]) were collected to analyze the mass concentration and distribution characteristics of nine water-soluble ions (WSIs; F-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, and Ca2+) in Lvliang in China. The results of chemical composition analysis indicated that the average concentration of total WSIs was 29.08 µg·m-3 and accounted for 40.45% of PM2.5, 80.99% of which was attributable to SO42-, NH4+, and NO3-; the concentration demonstrated obvious distribution characteristics. NO3- and NH4+ primarily exist as NH4NO3 and (NH4)2SO4, respectively, in fine particles but as NaNO3 and NH4Cl, respectively, in coarse particles. The PM2.5 was alkaline overall, and K+ and NH4+ caused the highest RC/A values in autumn. Stationary sources contribute more to WSIs in particulates than mobile sources. The secondary transformation degree of SO2 was higher than that of NOx, especially in fine particles. The positive matrix factorization (PMF) and potential source contribution function (PSCF) models were combined to determine the sources of WSIs in PM2.5. Through use of the PMF model, five source factors were categorized: secondary aerosols (43.0%), biomass combustion (21.7%), coal combustion (17.6%), dust (10.9%), and vehicular traffic (6.8%). The results of the PSCF model suggested that the transport of pollutants from Shanxi, northwestern Shaanxi, Gansu, Inner Mongolia and Henan, had the greatest effect on air quality in Lvliang.


Assuntos
Poluentes Atmosféricos , Água , Água/química , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Poeira/análise , Íons/análise , China , Estações do Ano , Aerossóis/análise , Carvão Mineral/análise
19.
PLoS Pathog ; 16(10): e1008849, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33002095

RESUMO

Epstein-Barr virus (EBV) causes lymphomas and epithelial cell cancers. Though generally silent in B lymphocytes, this widely prevalent virus can cause endemic Burkitt lymphoma and post-transplant lymphoproliferative disorders/lymphomas in immunocompromised hosts. By learning how EBV breaches barriers to cell proliferation, we hope to undermine those strategies to treat EBV lymphomas and potentially other cancers. We had previously found that EBV, through activation of cellular STAT3 prevents phosphorylation of Chk1, and thereby, suppresses activation of the intra-S phase cell-cycle checkpoint, a potent barrier to oncogene-driven proliferation. This observation prompted us to examine the consequences on DNA repair since homologous recombination repair, the most error-free form, requires phosphoChk1. We now report that the defect in Chk1 phosphorylation also curtails RAD51 nucleation, and thereby, homologous recombination repair of DNA double strand breaks. The resulting reliance on error-prone microhomology-mediated end-joining (MMEJ) repair makes EBV-transformed cells susceptible to PARP inhibition and simultaneous accrual of genome-wide deletions and insertions resulting from synthesis-dependent MMEJ. Analysis of transcriptomic and drug susceptibility data from hundreds of cancer lines reveals a STAT3-dependent gene-set predictive of susceptibility of cancers to synthetic lethal PARP inhibition. These findings i) demonstrate how the tumor virus EBV re-shapes cellular DNA repair, ii) provide the first genome-wide evidence for insertions resulting from MMEJ in human cells, and iii) expand the range of cancers (EBV-related and -unrelated) that are likely to respond to synthetic lethal inhibitors given the high prevalence of cancers with constitutively active STAT3.


Assuntos
Linfócitos B/virologia , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Quebras de DNA de Cadeia Dupla , Infecções por Vírus Epstein-Barr/virologia , Reparo de DNA por Recombinação , Fator de Transcrição STAT3/metabolismo , Adolescente , Adulto , Linfócitos B/citologia , Linfócitos B/metabolismo , Proteína BRCA1/genética , Proteína BRCA2/genética , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Linfoma de Burkitt/virologia , Proliferação de Células , Reparo do DNA por Junção de Extremidades , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Neoplasias/genética , Neoplasias/patologia , Neoplasias/virologia , Fosforilação , Fator de Transcrição STAT3/genética , Adulto Jovem
20.
Chemistry ; 28(67): e202202432, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36028597

RESUMO

Nb2 O5 possesses superior fast Li+ storage capability for LIB anodes, benefiting from its fast pseudocapacitive behavior and low volumetric change within the cycling processes. However, the poor electric conductivity for Nb2 O5 restricts its reaction kinetics and rate property. Herein, Nb2 O5 /carbon (C) submicrostructures are fabricated by solvothermal method followed by calcination process. The Nb2 O5 /C submicrostructures exhibit outstanding rate behavior and cyclic performance (332 (194) mAh g-1 after 1000 cycles at 1 (5) A g-1 ). The superior electrochemical property is attributed to the distinctive structure for Nb2 O5 /C submicrostructures, in which Nb2 O5 nanoparticles uniformly distributed within Nb2 O5 /C composite can protect Nb2 O5 nanoparticles from agglomeration, and the porous carbon matrix can enhance electron/ion conductivity. This work furnishes a novel strategy for fabricating Nb2 O5 /C submicrostructures with superior Li+ storage performance, which can be potentially used to design other metal oxide/C submicrostructures for second battery anode.

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