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1.
J Biol Chem ; 300(6): 107335, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705394

RESUMO

Endoplasmic reticulum (ER) stress, a common cellular stress response induced by various factors that interfere with cellular homeostasis, may trigger cell apoptosis. Autophagy is an important and conserved mechanism for eliminating aggregated proteins and maintaining protein stability of cells, which is closely associated with ER stress and ER stress-induced apoptosis. In this paper, we report for the first time that Hhatl, an ER-resident protein, is downregulated in response to ER stress. Hhatl overexpression alleviated ER stress and ER stress induced apoptosis in cells treated with tunicamycin or thapsigargin, whereas Hhatl knockdown exacerbated ER stress and apoptosis. Further study showed that Hhatl attenuates ER stress by promoting autophagic flux. Mechanistically, we found that Hhatl promotes autophagy by associating with autophagic protein LC3 (microtubule-associated protein 1A/1B-light chain 3) via the conserved LC3-interacting region motif. Noticeably, the LC3-interacting region motif was essential for Hhatl-regulated promotion of autophagy and reduction of ER stress. These findings demonstrate that Hhatl ameliorates ER stress via autophagy activation by interacting with LC3, thereby alleviating cellular pressure. The study indicates that pharmacological or genetic regulation of Hhatl-autophagy signaling might be potential for mediating ER stress and related diseases.


Assuntos
Autofagia , Estresse do Retículo Endoplasmático , Proteínas Associadas aos Microtúbulos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Humanos , Apoptose/efeitos dos fármacos , Células HEK293 , Células HeLa , Tunicamicina/farmacologia
2.
PLoS Pathog ; 19(2): e1011166, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36753521

RESUMO

Congenital human cytomegalovirus (HCMV) infection causes severe damage to the fetal brain, and the underlying mechanisms remain elusive. Cytokine signaling is delicately controlled in the fetal central nervous system to ensure proper development. Here we show that suppressor of cytokine signaling 3 (SOCS3), a negative feedback regulator of the IL-6 cytokine family signaling, was upregulated during HCMV infection in primary neural progenitor cells (NPCs) with a biphasic expression pattern. From viral protein screening, pUL97 emerged as the viral factor responsible for prolonged SOCS3 upregulation. Further, by proteomic analysis of the pUL97-interacting host proteins, regulatory factor X 7 (RFX7) was identified as the transcription factor responsible for the regulation. Depletion of either pUL97 or RFX7 prevented the HCMV-induced SOCS3 upregulation in NPCs. With a promoter-luciferase activity assay, we demonstrated that the pUL97 kinase activity and RFX7 were required for SOCS3 upregulation. Moreover, the RFX7 phosphorylation level was increased by either UL97-expressing or HCMV-infection in NPCs, suggesting that pUL97 induces RFX7 phosphorylation to drive SOCS3 transcription. We further revealed that elevated SOCS3 expression impaired NPC proliferation and migration in vitro and caused NPCs migration defects in vivo. Taken together, these findings uncover a novel regulatory mechanism of sustained SOCS3 expression in HCMV-infected NPCs, which perturbs IL-6 cytokine family signaling, leads to NPCs proliferation and migration defects, and consequently affects fetal brain development.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Humanos , Citomegalovirus/fisiologia , Interleucina-6/metabolismo , Proteômica , Fatores de Transcrição/metabolismo , Células-Tronco , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
3.
BMC Biol ; 22(1): 33, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331785

RESUMO

BACKGROUND: Ribosomal protein SA (RPSA) of human brain microvascular endothelial cells (HBMECs) can transfer from the cytosol to the cell surface and act as a receptor for some pathogens, including Streptococcus suis serotype 2 (SS2), a zoonotic pathogen causing meningitis in pigs and humans. We previously reported that SS2 virulence factor enolase (ENO) binds to RPSA on the cell surface of HBMECs and induces apoptosis. However, the mechanism that activates RPSA translocation to the cell surface and induces ENO-mediated HBMEC apoptosis is unclear. RESULTS: Here, we show that RPSA localization and condensation on the host cell surface depend on its internally disordered region (IDR). ENO binds to the IDR of RPSA and promotes its interaction with RPSA and vimentin (VIM), which is significantly suppressed after 1,6-Hexanediol (1,6-Hex, a widely used tool to disrupt phase separation) treatment, indicating that ENO incorporation and thus the concentration of RPSA/VIM complexes via co-condensation. Furthermore, increasing intracellular calcium ions (Ca2+) in response to SS2 infection further facilitates the liquid-like condensation of RPSA and aggravates ENO-induced HBMEC cell apoptosis. CONCLUSIONS: Together, our study provides a previously underappreciated molecular mechanism illuminating that ENO-induced RPSA condensation activates the migration of RPSA to the bacterial cell surface and stimulates SS2-infected HBMEC death and, potentially, disease progression. This study offers a fresh avenue for investigation into the mechanism by which other harmful bacteria infect hosts via cell surfaces' RPSA.


Assuntos
Infecções Estreptocócicas , Streptococcus suis , Humanos , Animais , Suínos , Células Endoteliais/metabolismo , Sorogrupo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Encéfalo/metabolismo , Apoptose , Proteínas Ribossômicas/metabolismo , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/microbiologia
4.
Cell Immunol ; 395-396: 104781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38159414

RESUMO

Pulmonary sarcoidosis is an immune-mediated disorder closely related to Th17/Treg cell imbalance. Dexamethasone has been shown to regulate inflammation and immune responses in sarcoidosis patients. However, the underlying mechanisms of dexamethasone regulating Th17/Treg balance in sarcoidosis remain elusive. Herein, we elucidated the function role of TGF-ß/Smad3 signaling in pulmonary sarcoidosis development and explored the underlying mechanism of dexamethasone in treating pulmonary sarcoidosis. We found that the TGF-ß/Smad3 pathway was inactivated in pulmonary sarcoidosis patients. Propionibacterium acnes (PA) induced mouse model was generated to investigate the function of TGF-ß/Smad3 signaling in vivo. Data indicated that IL17A inhibition with neutralizing antibody and activation of TGF-ß/Smad3 signaling with SRI-011381 alleviated granuloma formation in the sarcoidosis mouse model. Moreover, we revealed that the Th17/Treg cell ratio was increased with PA treatment in mouse bronchoalveolar lavage fluid (BALF) and peripheral blood. The concentration of cytokines produced by Th17 cells (IL-17A, IL-23) was up-regulated in the BALF of PA-treated mice, while those produced by Tregs (IL-10, TGF-ß1) presented significant reduction. The treatment of IL-17A neutralizing antibody or SRI-011381 was demonstrated to rescue the PA-induced changes in the concentration of IL-17A, IL-23, IL-10, and TGF-ß1. Additionally, we demonstrated that dexamethasone treatment activated the TGF-ß/Smad3 signaling in the lung tissues of pulmonary sarcoidosis mice. Dexamethasone was also revealed to promote the rebalancing of the Th17/Treg ratio and attenuated the granuloma formation in pulmonary sarcoidosis. In conclusion, dexamethasone activates the TGF-ß/Smad3 signaling and induces Th17/Treg rebalance, alleviating pulmonary sarcoidosis, which suggests the potential of dexamethasone in treating pulmonary sarcoidosis.


Assuntos
Dexametasona , Sarcoidose Pulmonar , Animais , Humanos , Camundongos , Anticorpos Neutralizantes/farmacologia , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Granuloma/prevenção & controle , Interleucina-10/metabolismo , Interleucina-17 , Interleucina-23/metabolismo , Sarcoidose Pulmonar/tratamento farmacológico , Linfócitos T Reguladores , Células Th17 , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1
5.
Inorg Chem ; 63(15): 6701-6713, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563144

RESUMO

The singlet oxygen (1O2) oxidation process activated by metal-free catalysts has recently attracted considerable attention for organic pollutant degradation; however, the 1O2 formation remains controversial. Simultaneously, the catalytic activity of the metal-free catalyst limits the practical application. In this study, carbon nitride (HCCN) containing an intramolecular homojunction, a kind of metal-free catalyst, exhibits excellent activity compared to g-C3N4 (CN) and crystalline carbon nitride (HCN) for tetracycline hydrochloride degradation through the H2O2-based Fenton-like reaction. The rate constant for HCCN increased about 16.1 and 8.9 times than that of CN and HCN, respectively. The activity of HCCN was enhanced, and the dominant reactive oxygen species (ROS) changed from hydroxyl radicals (•OH) to 1O2 with an increase in pH from 4.5 to 11.5. A novel formation pathway of 1O2 was revealed. This result is different from the normal reference, in which •OH is always the primary ROS in the H2O2-based Fenton-like reaction. This study may provide a possible strategy for the investigation on the nonradical oxidation process in the Fenton-like reaction.

6.
Inhal Toxicol ; 36(4): 275-281, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38836332

RESUMO

Multiwalled carbon nanotubes (MWCNTs) have numerous applications in the field of carbon nanomaterials. However, the associated toxicity concerns have increased significantly because of their widespread use. The inhalation of MWCNTs can lead to nanoparticle deposition in the lung tissue, causing inflammation and health risks. In this study, celastrol, a natural plant medicine with potent anti-inflammatory properties, effectively reduced the number of inflammatory cells, including white blood cells, neutrophils, and lymphocytes, and levels of inflammatory cytokines, such as IL-1ß, IL-6, and TNF-α, in mice lungs exposed to MWCNTs. Moreover, celastrol inhibited the activation of the NF-κB-signaling pathway. This study confirmed these findings by demonstrating comparable reductions in inflammation upon exposure to MWCNTs in mice with the deletion of NF-κB (P50-/-). These results indicate the utility of celastrol as a promising pharmacological agent for preventing MWCNT-induced lung tissue inflammation.


Assuntos
Nanotubos de Carbono , Triterpenos Pentacíclicos , Pneumonia , Transdução de Sinais , Triterpenos , Animais , Masculino , Camundongos , Anti-Inflamatórios/farmacologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/química , Citocinas/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nanotubos de Carbono/toxicidade , NF-kappa B/metabolismo , Triterpenos Pentacíclicos/farmacologia , Pneumonia/induzido quimicamente , Pneumonia/tratamento farmacológico , Pneumonia/prevenção & controle , Pneumonia/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia
7.
Hepatobiliary Pancreat Dis Int ; 23(3): 300-309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38057185

RESUMO

BACKGROUND: Visceral adipose tissue (VAT) has been linked to the severe acute pancreatitis (SAP) prognosis, although the underlying mechanism remains unclear. It has been reported that pyroptosis worsens SAP. The present study aimed to verify whether mesenteric adipose tissue (MAT, a component of VAT) can cause secondary intestinal injury through the pyroptotic pathway. METHODS: Thirty-six male Sprague Dawley (SD) rats were divided into six different groups. Twelve rats were randomly divided into the SAP and control groups. We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats. Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution (PBS). The remaining twelve SAP rats were first injected with MAT B lymphocytes, and then with MCC950 (NLRP3 inhibitor) or PBS. We collected blood and tissue samples from pancreas, gut and MAT for analysis. RESULTS: Compared to the control rats, the SAP group showed inflammation in MAT, including higher expression of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6), lower expression of IL-10, and histological changes. Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages. The SAP rats also exhibited intestinal injury, characterized by lower expression of zonula occludens-1 (ZO-1) and occludin, higher levels of lipopolysaccharide and diamine oxidase, and pathological changes. The expression of NLRP3 and n-GSDMD, which are responsible for pyroptosis, was increased in the intestine of SAP rats. The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT. The upregulation of pyroptosis reduced tight junction in the intestine, which contributed to the SAP progression, including higher inflammatory indicators and worse histological changes. The administration of MCC950 to SAP + MAT B rats downregulated pyroptosis, which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP. CONCLUSIONS: In SAP, MAT B lymphocytes aggravated local inflammation, and promoted the injury to the intestine through the enteric pyroptotic pathway.


Assuntos
Pancreatite , Ratos , Masculino , Animais , Pancreatite/induzido quimicamente , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Mucosa Intestinal , Piroptose , Doença Aguda , Inflamação/metabolismo , Fator de Necrose Tumoral alfa , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Linfócitos B/metabolismo , Linfócitos B/patologia
8.
Neuromodulation ; 27(2): 295-301, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930296

RESUMO

OBJECTIVE: Sacral nerve stimulation (SNS) is emerging as a novel treatment for irritable bowel syndrome (IBS). However, its effects are limited, and the underlying mechanisms remain largely unknown. MATERIALS AND METHODS: In this study, rats were divided into three groups (n = 12 rats per group): 1) the SNS group; 2) the sham SNS group (the sham group for short); and 3) the control group. The SNS and sham groups were exposed to chronic and acute stress to establish an IBS model. Electrode implantation surgery was performed in rats with the IBS model. The SNS group received electrical stimulation for 30 minutes every day for seven days. Abdominal withdrawal reflex (AWR) was used to evaluate the effect of SNS on visceral sensitivity in diarrhea-predominant IBS (IBS-D) rats. The frequency domain of heart rate variability (HRV) was analyzed to assess the effect of SNS on regulating the autonomic function. The expression of transient receptor potential vanilloid 1 (TRPV1) in the colon, spinal cord, and hippocampus was detected by immunohistochemistry to explore the mechanism of SNS in IBS-D rats. RESULTS: Compared with the sham group, AWR scores were significantly decreased under different gas volumes of stimulation of 0.4, 0.6, and 0.8 ml for rectal distention in the SNS group (all p < 0.05). However, there was no significant difference <1.0 ml between the two groups (p > 0.05). Compared with the sham group, the frequency domain indexes of HRV were significantly altered. Normalized low-frequency power and low frequency-to-high frequency ratio were significantly decreased, and normalized high-frequency power was significantly increased in the SNS group (all p < 0.05). Moreover, the expression of TRPV1 in the spinal cord and colon in the SNS group was significantly decreased compared with the sham group (both p < 0.05). These results suggested that chronic SNS not only improved the visceral sensitivity and autonomic dysfunction but also decreased the expression of TRPV1 in the spinal cord-gut tissue in IBS-D rats. CONCLUSION: Chronic SNS was found to have an inhibitory effect on visceral hypersensitivity in IBS-D rats, providing experimental evidence for its potential clinical application in IBS.


Assuntos
Síndrome do Intestino Irritável , Ratos , Animais , Síndrome do Intestino Irritável/terapia , Ratos Sprague-Dawley , Medula Espinal , Diarreia
9.
Carcinogenesis ; 44(6): 463-475, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37158456

RESUMO

Circular RNAs (circRNAs) have been accepted to play key roles in the development and progression of mutiple cancers including colorectal cancer (CRC). Here, we identified circ-METTL9, derived from 2 to 4 exons of METTL9 gene, may promote CRC progression by accelerating cell cycle progression. However, the role and mechanism of circ-METTL9 in CRC remains unclear. Based on our data, the expression of circ-METTL9 was significantly upregulated in CRC tissues and markedly increased in advanced tumors in CRC patients. Functional experiments demonstrated that circ-METTL9 overexpression promoted CRC cells proliferation and migration in vitro, and simultaneously enhanced CRC tumor growth and metastasis in vivo. Mechanistically, RNA immunoprecipitation (RIP) assays proved that circ-METTL9 might be a miRNA sponge, and RNA pulldown assays showed the interaction between circ-METTL9 and miR-551b-5p. Notably, cyclin-dependent kinase 6 (CDK6), a key regulator in cell cycle, is a conserved downstream target of miR-551b-5p. Taken together, our findings highlight a novel oncogenic function of circ-METTL9 in CRC progression via circ-METTL9/miR-551b-5p/CDK6 axis, which may serve as a prognostic biomarker and therapeutic target for CRC patients.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Quinase 6 Dependente de Ciclina/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Metiltransferases/metabolismo
10.
BMC Genomics ; 24(1): 235, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37138231

RESUMO

BACKGROUND: DNA hypermethylation at promoter CpG islands (CGIs) is a hallmark of cancers and could lead to dysregulation of gene expression in the development of cancers, however, its dynamics and regulatory mechanisms remain elusive. Bivalent genes, that direct development and differentiation of stem cells, are found to be frequent targets of hypermethylation in cancers. RESULTS: Here we performed comprehensive analysis across multiple cancer types and identified that the decrease in H3K4me1 levels coincides with DNA hypermethylation at the bivalent promoter CGIs during tumorigenesis. Removal of DNA hypermethylation leads to increment of H3K4me1 at promoter CGIs with preference for bivalent genes. Nevertheless, the alteration of H3K4me1 by overexpressing or knockout LSD1, the demethylase of H3K4, doesn't change the level or pattern of DNA methylation. Moreover, LSD1 was found to regulate the expression of a bivalent gene OVOL2 to promote tumorigenesis. Knockdown of OVOL2 in LSD1 knockout HCT116 cells restored the cancer cell phenotype. CONCLUSION: In summary, our work identified a universal indicator that can pre-mark DNA hypermethylation in cancer cells, and dissected the interplay between H3K4me1 and DNA hypermethylation in detail. Current study also reveals a novel mechanism underlying the oncogenic role of LSD1, providing clues for cancer therapies.


Assuntos
Metilação de DNA , Histonas , Humanos , Histonas/metabolismo , Código das Histonas , Carcinogênese/genética , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , DNA/metabolismo , Ilhas de CpG , Fatores de Transcrição/metabolismo
11.
J Am Chem Soc ; 145(12): 6944-6952, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36920031

RESUMO

Enantioselective metallaphotoredox catalysis, which combines photoredox catalysis and asymmetric transition-metal catalysis, has become an effective approach to achieve stereoconvergence under mild conditions. Although many impressive synthetic approaches have been developed to access central chirality, the construction of axial chirality by metallaphotoredox catalysis still remains underexplored. Herein, we report two visible light-induced cobalt-catalyzed asymmetric reductive couplings of biaryl dialdehydes to synthesize axially chiral aldehydes (60 examples, up to 98% yield, >19:1 dr, and >99% ee). This protocol shows good functional group tolerance, broad substrate scope, and excellent diastereo- and enantioselectivity.

12.
J Am Chem Soc ; 145(14): 7983-7991, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36974976

RESUMO

Conjugate addition is among the most important synthetic protocols for constructing carbon skeletons and is widely used to synthesize natural products and drugs. However, asymmetric catalysis studies have mainly focused on constructing stereogenic centers arising from conjugate alkenes. Here, we report the first photoinduced cobalt-catalyzed dynamic kinetic reductive conjugate addition reaction that enables the formation of heterobiaryls with axial chirality (45 examples, up to 91% yield and 97% ee). This method features mild reaction conditions, good functional-group tolerance, and excellent enantiomeric control. Significantly, large amounts of metal waste and precious metal catalysts can be avoided under these conditions. Migration of the chiral arylcobalt species into the alkene might be the rate-determining step based on kinetic studies.

13.
J Virol ; 96(2): e0147621, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34730396

RESUMO

Human cytomegalovirus (HCMV) establishes a persistent/latent infection after primary infection, and the host factor(s) plays a key role in regulating HCMV infection status. The spread of reactivated HCMV via the hematogenous or neural route usually results in severe diseases in newborns and immunocompromised individuals. As the primary reservoirs in vivo, cells of myeloid lineage have been utilized extensively to study HCMV infection. However, the molecular mechanism of HCMV latency/reactivation in neural cells is still poorly understood. We previously showed that HCMV-infected T98G cells maintain a large number of viral genomes and support HCMV reactivation from latency upon cAMP/IBMX treatment. Here, we employed an isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomics to characterize cellular protein changes during HCMV latency and reactivation in T98G cells. A total of 168 differentially expressed proteins (DEPs) were identified, including 89 proteins in latency and 85 proteins in reactivation. Bioinformatics analysis showed that a few biological pathways were associated with HCMV latency or reactivation. Moreover, we validated 16 DEPs by both mRNA and protein expression profiles and further evaluated the effects of ApoE and the phosphatidylinositol 3-kinase (PI3K) pathway on HCMV infection. ApoE knockdown reduced HCMV loads and virus release, whereas overexpressing ApoE hampered HCMV latent infection, indicating a role in HCMV latency establishment/maintenance. Blocking the PI3K pathway by LY294002, a PI3K inhibitor, induced HCMV reactivation from latency in T98G cells. Overall, this comparative proteomics analysis delineates the cellular protein changes during HCMV latency and reactivation and provides a road map to advance our understanding of the mechanism(s) in the context of neural cells. IMPORTANCE Human cytomegalovirus (HCMV) is a highly transmissible betaherpesvirus that has a prevalence of 60% to 90% worldwide. This opportunist pathogen poses a significant threat to newborns and immunosuppressed individuals. One major obstacle for developing effective therapeutics is a poor understanding of HCMV latency/reactivation mechanisms. This study presents, for the first time, a systemic analysis of host cell protein expression changes during HCMV latency establishment and reactivation processes in neural cells. We showed that ApoE was downregulated by HCMV to facilitate latent infection. Also, the proteomics analysis has associated a few PI3K pathway-related proteins with HCMV reactivation. Altogether, this study highlights multiple host proteins and signaling pathways that can be further investigated as potential druggable targets for HCMV-related diseases, especially brain disorders.


Assuntos
Citomegalovirus/fisiologia , Proteômica , Ativação Viral , Latência Viral , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Linhagem Celular Tumoral , Ontologia Genética , Humanos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Mapas de Interação de Proteínas , Proteoma/genética , Proteoma/metabolismo , Transdução de Sinais
14.
J Virol ; 96(5): e0182721, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35020472

RESUMO

Human cytomegalovirus (HCMV) has a large (∼235 kb) genome with more than 200 predicted open reading frames that exploits numerous cellular factors to facilitate its replication. A key feature of HCMV-infected cells is the emergence of a distinctive membranous cytoplasmic compartment termed the virion assembly compartment (vAC). Here, we report that host protein WD repeat domain 11 (WDR11) plays a key role in vAC formation and virion morphogenesis. We found that WDR11 was upregulated at both mRNA and protein levels during HCMV infection. At the late stage of HCMV replication, WDR11 relocated to the vAC and colocalized with markers of the trans-Golgi network (TGN) and vAC. Depletion of WDR11 hindered HCMV-induced membrane reorganization of the Golgi and TGN, altered vAC formation, and impaired HCMV secondary envelopment and virion morphogenesis. Further, motifs critical for the localization of WDR11 in TGN were identified by alanine-scanning mutagenesis. Mutation of these motifs led to WDR11 mislocation outside the TGN and loss of vAC formation. Taken together, these data indicate that host protein WDR11 is required for efficient viral replication at the stage of virion assembly, possibly by facilitating the remodeling of the endomembrane system for vAC formation and virion morphogenesis. IMPORTANCE During the late phase of human cytomegalovirus (HCMV) infection, the endomembrane system is dramatically reorganized, resulting in the formation of a unique structure termed the virion assembly compartment (vAC), which is critical for the assembly of infectious virions. The mechanism of HCMV-induced vAC formation is still not fully understood. In this report, we identified a host factor, WDR11, that plays an important role in vAC formation. Our findings argue that WDR11 contributes to the relocation of the Golgi and trans-Golgi network to the vAC, a membrane reorganization process that appears to be required for efficient virion maturation. The present work provides new insights into the vAC formation and HCMV virion morphogenesis and a potential novel target for antiviral treatment.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Interações entre Hospedeiro e Microrganismos , Repetições WD40 , Citomegalovirus/genética , Citomegalovirus/metabolismo , Infecções por Citomegalovirus/fisiopatologia , Infecções por Citomegalovirus/virologia , Humanos , Morfogênese , Vírion/metabolismo , Montagem de Vírus/genética , Replicação Viral/genética , Repetições WD40/genética , Rede trans-Golgi/metabolismo
15.
J Med Virol ; 95(2): e28574, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772841

RESUMO

Human cytomegalovirus (HCMV) preferentially targets neural progenitor cells (NPCs) in congenitally infected fetal brains, inducing neurodevelopmental disorders. While HCMV expresses several microRNAs (miRNAs) during infection, their roles in NPC infection are unclear. Here, we characterized expression of cellular and viral miRNAs in HCMV-infected NPCs during early infection by microarray and identified seven differentially expressed cellular miRNAs and six significantly upregulated HCMV miRNAs. Deep learning approaches were used to identify potential targets of significantly upregulated HCMV miRNAs against differentially expressed cellular messenger RNA (mRNAs), and the associations with miRNA-mRNA expression changes were observed. Gene ontology enrichment analysis indicated cellular gene targets were significantly enriched in pathways involved in neurodevelopment and cell-cycle processes. Viral modulation of selected miRNAs and cellular gene targets involved in neurodevelopmental processes were further validated by real-time quantitative reverse transcription polymerase chain reaction. Finally, a predicted 3' untranslated region target site of hcmv-miR-US25-1 in Jag1, a factor important for neurogenesis, was confirmed by mutagenesis. Reduction of Jag1 RNA and protein levels in NPCs was observed in response to transient expression of hcmv-miR-US25-1. A hcmv-miR-US25-1 mutant virus (ΔmiR-US25) displayed limited ability to downregulate Jag1 mRNA levels and protein levels during the early infection stage compared with the wild type virus. Our collective experimental and computational investigation of miRNAs and cellular mRNAs expression in HCMV-infected NPCs yields new insights into the roles of viral miRNAs in regulating NPC fate and their contributions to HCMV neuropathogenesis.


Assuntos
Infecções por Citomegalovirus , MicroRNAs , Humanos , MicroRNAs/genética , Citomegalovirus/genética , Células-Tronco/metabolismo
16.
Blood ; 137(1): 115-125, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33205809

RESUMO

Ciraparantag, an anticoagulant reversal agent, is a small molecule specifically designed to bind noncovalently by charge-charge interaction to unfractionated heparin and low-molecular-weight heparin. It shows binding characteristics that are similar to those of direct oral anticoagulants (DOACs). A dynamic light-scattering methodology was used to demonstrate ciraparantag's binding to the heparins and DOACs and its lack of binding to a variety of proteins including coagulation factors and commonly used drugs. Ciraparantag reaches maximum concentration within minutes after IV administration with a half-life of 12 to 19 minutes. It is primarily hydrolyzed by serum peptidases into 2 metabolites, neither of which has substantial activity. Ciraparantag and its metabolites are recovered almost entirely in the urine. In animal models of bleeding (rat tail transection and liver laceration), a single IV dose of ciraparantag given at peak concentrations of the anticoagulant, but before the bleeding injury, significantly reduced the blood loss. Ciraparantag, given after the bleeding injury, also significantly reduced blood loss. It appears to have substantial ability to reduce blood loss in animal models in which a variety of anticoagulants are used and has potential as a useful DOAC reversal agent.


Assuntos
Arginina/análogos & derivados , Coagulação Sanguínea/efeitos dos fármacos , Hemorragia/tratamento farmacológico , Piperazinas/farmacologia , Piperazinas/farmacocinética , Animais , Anticoagulantes/efeitos adversos , Arginina/metabolismo , Arginina/farmacocinética , Arginina/farmacologia , Feminino , Meia-Vida , Hemorragia/induzido quimicamente , Humanos , Masculino , Piperazinas/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Opt Express ; 31(11): 17437-17449, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381478

RESUMO

In order to solve the difficulty of traditional phase measuring deflectometry (PMD) in considering precision and speed, an orthogonal encoding PMD method based on deep learning is presented in this paper. We demonstrate for, what we believe to be, the first time that deep learning techniques can be combined with dynamic-PMD and can be used to reconstruct high-precision 3D shapes of specular surfaces from single-frame distorted orthogonal fringe patterns, enabling high-quality dynamic measurement of specular objects. The experimental results prove that the phase and shape information measured by the proposed method has high accuracy, almost reaching the results obtained by the ten-step phase-shifting method. And the proposed method also has excellent performance in dynamic experiments, which is of great significance to the development of optical measurement and fabrication areas.

18.
Scand J Gastroenterol ; 58(5): 443-447, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36314511

RESUMO

OBJECTIVES: Gastroesophageal reflux disease (GERD) has overlapping symptoms with functional disorders such as functional heart burn. Twenty-four-hour pH with impedance monitoring is useful for differentiation. The intraluminal impedance change with meal in distal esophagus is not investigated. METHODS: We performed a retrospective investigation of clinical files, 24-hour pH with intraluminal impedance monitoring in patients with GERD and functional disorders. The post-reflux swallow induced peristaltic wave (PSPW) index as well as the impedance in distal esophagus before the first meal and 30 min and 60 min after the meal were measured and analyzed. RESULTS: A significant decrease of intraluminal impedance in distal esophagus was noted at 30 min (ΔI30min -301.5 [747.5] Ω, p = 0.018) and recovered at 60 min (ΔI60min -194.6 [766.0] Ω, p = 0.126) after meals in GERD patients. On the other hand, there was no significant change of impedance in patients with functional disorders. There were positive correlations between ΔI30min and PSPW index (correlation = 0.232, p = 0.038). Comparing GERD to functional disorders, the best cut-off value for ΔI30min was -212Ω with 74.4% sensitivity and 60.5% specificity. CONCLUSIONS: The intraluminal impedance in distal esophagus was lowered after meals in GERD patients other than functional disorders. This impedance change was correlated with PSPW index and could help differentiate GERD from functional disorders.


Assuntos
Monitoramento do pH Esofágico , Refluxo Gastroesofágico , Humanos , Estudos Retrospectivos , Impedância Elétrica , Refluxo Gastroesofágico/diagnóstico , Refeições , Concentração de Íons de Hidrogênio
19.
Inorg Chem ; 62(21): 8357-8371, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37186873

RESUMO

Multiple oxidation states of first-row transition-metal cations were always doped in g-C3N4 to enhance the catalytic activity by the synergistic action between the cations in the Fenton-like reaction. It remains a challenge for the synergistic mechanism when the stable electronic centrifugation (3d10) of Zn2+ was used. In this work, Zn2+ was facilely introduced in Fe-doped g-C3N4 (named xFe/yZn-CN). Compared with Fe-CN, the rate constant of the tetracycline hydrochloride (TC) degradation increased from 0.0505 to 0.0662 min-1 for 4Fe/1Zn-CN. The catalytic performance was more outstanding than those of similar catalysts reported. The catalytic mechanism was proposed. With the introduction of Zn2+ in 4Fe/1Zn-CN, the atomic percent of Fe (Fe2+ and Fe3+) and the molar ratio of Fe2+ to Fe3+ at the catalyst's surface increased, where Fe2+ and Fe3+ were the active sites for adsorption and degradation. In addition, the band gap of 4Fe/1Zn-CN decreased, leading to enhanced electron transfer and conversion from Fe3+ to Fe2+. These changes resulted in the excellent catalytic performance of 4Fe/1Zn-CN. Radicals •OH, •O2-, and 1O2 formed in the reaction and took different actions under various pH values. 4Fe/1Zn-CN exhibited excellent stability after five cycles under the same conditions. These results may give a strategy for synthesizing Fenton-like catalysts.

20.
Inorg Chem ; 62(6): 2652-2662, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36719869

RESUMO

Coordination polymers (CPs) have recently emerged as promising candidates for heterogeneous photocatalysis due to their structural designability and tunable properties. Herein, we developed two novel Ag(I)-calix[4]arene coordination polymers with the formula {[Ag2(µ-NO3)L1]}n (CP 1) and {[AgL1]·PF6}n (CP 2) (L1 = 2-mercapto-5-methyl-1,3,4-thiadiazole resorcinol calix[4]arene). Crystallography revealed that anion coordination and self-inclusion behavior induced the cavitand and silver ions to self-assemble into well-defined CPs 1 and 2 with different topological coordination frameworks, respectively. Furthermore, CPs 1 and 2 display high photocatalytic activity for the photodegradation of rhodamine B (RhB) and methyl orange (MO) in an aqueous solution under mild conditions (WLED and UV irradiation). The comparison results demonstrate that CP 1 exhibited better photocatalytic performance than CP 2, which correlated well with the differences in their molecular structure and HOMO-LUMO energy gaps. The photocatalysis products and possible intermediates were successfully monitored and determined using mass spectrum, gas chromatography, and electron paramagnetic resonance measurements. The rational photocatalysis mechanism was further investigated and proposed.

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