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1.
Cell ; 184(3): 775-791.e14, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33503446

RESUMO

The molecular pathology of multi-organ injuries in COVID-19 patients remains unclear, preventing effective therapeutics development. Here, we report a proteomic analysis of 144 autopsy samples from seven organs in 19 COVID-19 patients. We quantified 11,394 proteins in these samples, in which 5,336 were perturbed in the COVID-19 patients compared to controls. Our data showed that cathepsin L1, rather than ACE2, was significantly upregulated in the lung from the COVID-19 patients. Systemic hyperinflammation and dysregulation of glucose and fatty acid metabolism were detected in multiple organs. We also observed dysregulation of key factors involved in hypoxia, angiogenesis, blood coagulation, and fibrosis in multiple organs from the COVID-19 patients. Evidence for testicular injuries includes reduced Leydig cells, suppressed cholesterol biosynthesis, and sperm mobility. In summary, this study depicts a multi-organ proteomic landscape of COVID-19 autopsies that furthers our understanding of the biological basis of COVID-19 pathology.


Assuntos
COVID-19/metabolismo , Regulação da Expressão Gênica , Proteoma/biossíntese , Proteômica , SARS-CoV-2/metabolismo , Autopsia , COVID-19/patologia , COVID-19/terapia , Feminino , Humanos , Masculino , Especificidade de Órgãos
2.
Nature ; 610(7931): 366-372, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198801

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly desmoplastic, aggressive cancer that frequently progresses and spreads by metastasis to the liver1. Cancer-associated fibroblasts, the extracellular matrix and type I collagen (Col I) support2,3 or restrain the progression of PDAC and may impede blood supply and nutrient availability4. The dichotomous role of the stroma in PDAC, and the mechanisms through which it influences patient survival and enables desmoplastic cancers to escape nutrient limitation, remain poorly understood. Here we show that matrix-metalloprotease-cleaved Col I (cCol I) and intact Col I (iCol I) exert opposing effects on PDAC bioenergetics, macropinocytosis, tumour growth and metastasis. Whereas cCol I activates discoidin domain receptor 1 (DDR1)-NF-κB-p62-NRF2 signalling to promote the growth of PDAC, iCol I triggers the degradation of DDR1 and restrains the growth of PDAC. Patients whose tumours are enriched for iCol I and express low levels of DDR1 and NRF2 have improved median survival compared to those whose tumours have high levels of cCol I, DDR1 and NRF2. Inhibition of the DDR1-stimulated expression of NF-κB or mitochondrial biogenesis blocks tumorigenesis in wild-type mice, but not in mice that express MMP-resistant Col I. The diverse effects of the tumour stroma on the growth and metastasis of PDAC and on the survival of patients are mediated through the Col I-DDR1-NF-κB-NRF2 mitochondrial biogenesis pathway, and targeting components of this pathway could provide therapeutic opportunities.


Assuntos
Carcinoma Ductal Pancreático , Colágeno Tipo I , Receptor com Domínio Discoidina 1 , Transdução de Sinais , Animais , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Colágeno Tipo I/metabolismo , Receptor com Domínio Discoidina 1/metabolismo , Metaloproteinases da Matriz/metabolismo , Camundongos , Mitocôndrias/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Taxa de Sobrevida
3.
Nature ; 610(7931): 356-365, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198802

RESUMO

Hepatocellular carcinoma (HCC), the fourth leading cause of cancer mortality worldwide, develops almost exclusively in patients with chronic liver disease and advanced fibrosis1,2. Here we interrogated functions of hepatic stellate cells (HSCs), the main source of liver fibroblasts3, during hepatocarcinogenesis. Genetic depletion, activation or inhibition of HSCs in mouse models of HCC revealed their overall tumour-promoting role. HSCs were enriched in the preneoplastic environment, where they closely interacted with hepatocytes and modulated hepatocarcinogenesis by regulating hepatocyte proliferation and death. Analyses of mouse and human HSC subpopulations by single-cell RNA sequencing together with genetic ablation of subpopulation-enriched mediators revealed dual functions of HSCs in hepatocarcinogenesis. Hepatocyte growth factor, enriched in quiescent and cytokine-producing HSCs, protected against hepatocyte death and HCC development. By contrast, type I collagen, enriched in activated myofibroblastic HSCs, promoted proliferation and tumour development through increased stiffness and TAZ activation in pretumoural hepatocytes and through activation of discoidin domain receptor 1 in established tumours. An increased HSC imbalance between cytokine-producing HSCs and myofibroblastic HSCs during liver disease progression was associated with increased HCC risk in patients. In summary, the dynamic shift in HSC subpopulations and their mediators during chronic liver disease is associated with a switch from HCC protection to HCC promotion.


Assuntos
Carcinogênese , Carcinoma Hepatocelular , Células Estreladas do Fígado , Neoplasias Hepáticas , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Proliferação de Células , Colágeno Tipo I/metabolismo , Receptor com Domínio Discoidina 1/metabolismo , Progressão da Doença , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/patologia , Camundongos , Miofibroblastos/patologia
4.
Mol Cell ; 73(4): 788-802.e7, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30704899

RESUMO

mTORC1 and GSK3 play critical roles in early stages of (macro)autophagy, but how they regulate late steps of autophagy remains poorly understood. Here we show that mTORC1 and GSK3-TIP60 signaling converge to modulate autophagosome maturation through Pacer, an autophagy regulator that was identified in our recent study. Hepatocyte-specific Pacer knockout in mice results in impaired autophagy flux, glycogen and lipid accumulation, and liver fibrosis. Under nutrient-rich conditions, mTORC1 phosphorylates Pacer at serine157 to disrupt the association of Pacer with Stx17 and the HOPS complex and thus abolishes Pacer-mediated autophagosome maturation. Importantly, dephosphorylation of Pacer under nutrient-deprived conditions promotes TIP60-mediated Pacer acetylation, which facilitates HOPS complex recruitment and is required for autophagosome maturation and lipid droplet clearance. This work not only identifies Pacer as a regulator in hepatic autophagy and liver homeostasis in vivo but also reveals a signal integration mechanism involved in late stages of autophagy and lipid metabolism.


Assuntos
Autofagossomos/enzimologia , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Quinase 3 da Glicogênio Sintase/metabolismo , Metabolismo dos Lipídeos , Fígado/enzimologia , Lisina Acetiltransferase 5/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Transativadores/metabolismo , Acetilação , Animais , Autofagossomos/patologia , Proteínas Relacionadas à Autofagia/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Quinase 3 da Glicogênio Sintase/genética , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Gotículas Lipídicas/metabolismo , Fígado/patologia , Lisina Acetiltransferase 5/genética , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Ligação a Fosfato/genética , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Transdução de Sinais , Transativadores/genética , Proteínas Supressoras de Tumor
5.
Ann Neurol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860520

RESUMO

OBJECTIVE: The role of gamma-aminobutyric acid-ergic (GABAergic) neuron impairment in Alzheimer's disease (AD), and if and how transplantation of healthy GABAergic neurons can improve AD, remain unknown. METHODS: Human-derived medial ganglionic eminence progenitors (hiMGEs) differentiated from programmed induced neural precursor cells (hiNPCs) were injected into the dentate gyrus region of the hippocampus (HIP). RESULTS: We showed that grafts migrate to the whole brain and form functional synaptic connections in amyloid precursor protein gene/ presenilin-1 (APP/PS1) chimeric mice. Following transplantation of hiMGEs, behavioral deficits and AD-related pathology were alleviated and defective neurons were repaired. Notably, exosomes secreted from hiMGEs, which are rich in anti-inflammatory miRNA, inhibited astrocyte activation in vitro and in vivo, and the mechanism was related to regulation of CD4+ Th1 cells mediated tumor necrosis factor (TNF) pathway. INTERPRETATION: Taken together, these findings support the hypothesis that hiMGEs transplantation is an alternative treatment for neuronal loss in AD and demonstrate that exosomes with anti-inflammatory activity derived from hiMGEs are important factors for graft survival. ANN NEUROL 2024.

6.
Mol Psychiatry ; 29(3): 838-846, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38233469

RESUMO

Previous studies have shown that excessive alcohol consumption is associated with poor sleep. However, the health risks of light-to-moderate alcohol consumption in relation to sleep traits (e.g., insomnia, snoring, sleep duration and chronotype) remain undefined, and their causality is still unclear in the general population. To identify the association between alcohol consumption and multiple sleep traits using an observational and Mendelian randomization (MR) design. Observational analyses and one-sample MR (linear and nonlinear) were performed using clinical and individual-level genetic data from the UK Biobank (UKB). Two-sample MR was assessed using summary data from genome-wide association studies from the UKB and other external consortia. Phenotype analyses were externally validated using data from the National Health and Nutrition Examination Survey (2017-2018). Data analysis was conducted from January 2022 to October 2022. The association between alcohol consumption and six self-reported sleep traits (short sleep duration, long sleep duration, chronotype, snoring, waking up in the morning, and insomnia) were analysed. This study included 383,357 UKB participants (mean [SD] age, 57.0 [8.0] years; 46% male) who consumed a mean (SD) of 9.0 (10.0) standard drinks (one standard drink equivalent to 14 g of alcohol) per week. In the observational analyses, alcohol consumption was significantly associated with all sleep traits. Light-moderate-heavy alcohol consumption was linearly linked to snoring and the evening chronotype but nonlinearly associated with insomnia, sleep duration, and napping. In linear MR analyses, a 1-SD (14 g) increase in genetically predicted alcohol consumption was associated with a 1.14-fold (95% CI, 1.07-1.22) higher risk of snoring (P < 0.001), a 1.28-fold (95% CI, 1.20-1.37) higher risk of evening chronotype (P < 0.001) and a 1.24-fold (95% CI, 1.13-1.36) higher risk of difficulty waking up in the morning (P < 0.001). Nonlinear MR analyses did not reveal significant results after Bonferroni adjustment. The results of the two-sample MR analyses were consistent with those of the one-sample MR analyses, but with a slightly attenuated overall estimate. Our findings suggest that even low levels of alcohol consumption may affect sleep health, particularly by increasing the risk of snoring and evening chronotypes. The negative effects of alcohol consumption on sleep should be made clear to the public in order to promote public health.


Assuntos
Consumo de Bebidas Alcoólicas , Bancos de Espécimes Biológicos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Distúrbios do Início e da Manutenção do Sono , Sono , Humanos , Análise da Randomização Mendeliana/métodos , Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/epidemiologia , Masculino , Reino Unido/epidemiologia , Feminino , Pessoa de Meia-Idade , Sono/genética , Sono/fisiologia , Idoso , Distúrbios do Início e da Manutenção do Sono/genética , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Ronco/genética , Ronco/epidemiologia , Adulto , Fenótipo , Transtornos do Sono-Vigília/genética , Transtornos do Sono-Vigília/epidemiologia , Polimorfismo de Nucleotídeo Único/genética , Biobanco do Reino Unido
7.
EMBO Rep ; 24(6): e56128, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37042626

RESUMO

Surgery-induced renal ischemia and reperfusion (I/R) injury and nephrotoxic drugs like cisplatin can cause acute kidney injury (AKI), for which there is no effective therapy. Lipid accumulation is evident following AKI in renal tubules although the mechanisms and pathological effects are unclear. Here, we report that Ehmt2-encoded histone methyltransferase G9a is upregulated in patients and mouse kidneys after AKI. Renal tubular specific knockout of G9a (Ehmt2Ksp ) or pharmacological inhibition of G9a alleviates lipid accumulation associated with AKI. Mechanistically, G9a suppresses transcription of the lipolytic enzyme Ces1; moreover, G9a and farnesoid X receptor (FXR) competitively bind to the same promoter regions of Ces1. Ces1 is consistently observed to be downregulated in the kidney of AKI patients. Pharmacological inhibition of Ces1 increases lipid accumulation, exacerbates renal I/R-injury and eliminates the beneficial effects on AKI observed in Ehmt2Ksp mice. Furthermore, lipid-lowering atorvastatin and an FXR agonist alleviate AKI by activating Ces1 and reducing renal lipid accumulation. Together, our results reveal a G9a/FXR-Ces1 axis that affects the AKI outcome via regulating renal lipid accumulation.


Assuntos
Injúria Renal Aguda , Túbulos Renais , Camundongos , Animais , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Injúria Renal Aguda/genética , Injúria Renal Aguda/induzido quimicamente , Lipídeos , Rim/patologia , Camundongos Endogâmicos C57BL
8.
Exp Cell Res ; 435(2): 113929, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272106

RESUMO

Early repolarization syndrome (ERS) is defined as occurring in patients with early repolarization pattern who have survived idiopathic ventricular fibrillation with clinical evaluation unrevealing for other explanations. The pathophysiologic basis of the ERS is currently uncertain. The objective of the present study was to examine the electrophysiological mechanism of ERS utilizing induced pluripotent stem cells (iPSCs) and CRISPR/Cas9 genome editing. Whole genome sequencing was used to identify the DPP6 (c.2561T > C/p.L854P) variant in four families with sudden cardiac arrest induced by ERS. Cardiomyocytes were generated from iPSCs from a 14-year-old boy in the four families with ERS and an unrelated healthy control subject. Patch clamp recordings revealed more significant prolongation of the action potential duration (APD) and increased transient outward potassium current (Ito) (103.97 ± 18.73 pA/pF vs 44.36 ± 16.54 pA/pF at +70 mV, P < 0.05) in ERS cardiomyocytes compared with control cardiomyocytes. Of note, the selective correction of the causal variant in iPSC-derived cardiomyocytes using CRISPR/Cas9 gene editing normalized the Ito, whereas prolongation of the APD remained unchanged. ERS cardiomyocytes carrying DPP6 mutation increased Ito and lengthen APD, which maybe lay the electrophysiological foundation of ERS.

9.
Mol Cell ; 68(2): 323-335.e6, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29033323

RESUMO

Acetylation is increasingly recognized as one of the major post-translational mechanisms for the regulation of multiple cellular functions in mammalian cells. Acetyltransferase p300, which acetylates histone and non-histone proteins, has been intensively studied in its role in cell growth and metabolism. However, the mechanism underlying the activation of p300 in cells remains largely unknown. Here, we identify the homeostatic sensor mTORC1 as a direct activator of p300. Activated mTORC1 interacts with p300 and phosphorylates p300 at 4 serine residues in the C-terminal domain. Mechanistically, phosphorylation of p300 by mTORC1 prevents the catalytic HAT domain from binding to the RING domain, thereby eliminating intra-molecular inhibition. Functionally, mTORC1-dependent phosphorylation of p300 suppresses cell-starvation-induced autophagy and activates cell lipogenesis. These results uncover p300 as a direct target of mTORC1 and suggest that the mTORC1-p300 pathway plays a pivotal role in cell metabolism by coordinately controlling cell anabolism and catabolism.


Assuntos
Autofagia , Lipogênese , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Complexos Multiproteicos/genética , Fosforilação/genética , Domínios Proteicos , Serina-Treonina Quinases TOR/genética , Fatores de Transcrição de p300-CBP/genética
10.
Mol Cell ; 67(6): 907-921.e7, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28844862

RESUMO

The class III phosphoinositide 3-kinase VPS34 plays a key role in the regulation of vesicular trafficking and macroautophagy. So far, we know little about the molecular mechanism of VPS34 activation besides its interaction with regulatory proteins to form complexes. Here, we report that VPS34 is specifically acetylated by the acetyltransferase p300, and p300-mediated acetylation represses VPS34 activity. Acetylation at K771 directly diminishes the affinity of VPS34 for its substrate PI, while acetylation at K29 hinders the VPS34-Beclin 1 core complex formation. Inactivation of p300 induces VPS34 deacetylation, PI3P production, and autophagy, even in AMPK-/-, TSC2-/-, or ULK1-/- cells. In fasting mice, liver autophagy correlates well with p300 inactivation/VPS34 deacetylation, which facilitates the clearance of lipid droplets in hepatocytes. Thus, p300-dependent VPS34 acetylation/deacetylation is the physiological key to VPS34 activation, which controls the initiation of canonical autophagy and of non-canonical autophagy in which the upstream kinases of VPS34 can be bypassed.


Assuntos
Autofagia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Hepatócitos/enzimologia , Metabolismo dos Lipídeos , Fígado/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Processamento de Proteína Pós-Traducional , Estresse Fisiológico , Fatores de Transcrição de p300-CBP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Acetilação , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteína Beclina-1/metabolismo , Classe III de Fosfatidilinositol 3-Quinases/genética , Ativação Enzimática , Feminino , Células HEK293 , Células HeLa , Hepatócitos/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/genética , Fosfatos de Fosfatidilinositol/metabolismo , Ligação Proteica , Interferência de RNA , Transdução de Sinais , Transfecção , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Fatores de Transcrição de p300-CBP/genética
11.
BMC Genomics ; 25(1): 280, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493091

RESUMO

BACKGROUND: Atrial fibrillation (AF) is a prevalent arrhythmic condition resulting in increased stroke risk and is associated with high mortality. Electrolyte imbalance can increase the risk of AF, where the relationship between AF and serum electrolytes remains unclear. METHODS: A total of 15,792 individuals were included in the observational study, with incident AF ascertainment in the Atherosclerosis Risk in Communities (ARIC) study. The Cox regression models were applied to calculate the hazard ratio (HR) and 95% confidence interval (CI) for AF based on different serum electrolyte levels. Mendelian randomization (MR) analyses were performed to examine the causal association. RESULTS: In observational study, after a median 19.7 years of follow-up, a total of 2551 developed AF. After full adjustment, participants with serum potassium below the 5th percentile had a higher risk of AF relative to participants in the middle quintile. Serum magnesium was also inversely associated with the risk of AF. An increased incidence of AF was identified in individuals with higher serum phosphate percentiles. Serum calcium levels were not related to AF risk. Moreover, MR analysis indicated that genetically predicted serum electrolyte levels were not causally associated with AF risk. The odds ratio for AF were 0.999 for potassium, 1.044 for magnesium, 0.728 for phosphate, and 0.979 for calcium, respectively. CONCLUSIONS: Serum electrolyte disorders such as hypokalemia, hypomagnesemia and hyperphosphatemia were associated with an increased risk of AF and may also serve to be prognostic factors. However, the present study did not support serum electrolytes as causal mediators for AF development.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/genética , Fatores de Risco , Magnésio , Análise da Randomização Mendeliana , Cálcio , Potássio , Fosfatos , Eletrólitos , Estudo de Associação Genômica Ampla/métodos
12.
J Am Chem Soc ; 146(4): 2445-2451, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38230586

RESUMO

Spontaneous generation of H2O2 in sub-10 µm-sized water microdroplets has received increasing interest since its first discovery in 2019. On the other hand, due to the short lifetime of these microdroplets (rapid evaporation) and lack of suitable tools to real-time monitor the generation of H2O2 in individual microdroplets, such a seemingly thermodynamically unfavorable process has also raised vigorous debates on the origin of H2O2 and the underlying mechanism. Herein, we prepared water microdroplets with a long lifetime (>1 h) by virtue of microwell confinement and dynamically monitored the spontaneous generation of H2O2 in individual microdroplets via time-lapsed fluorescence imaging. It was unveiled that H2O2 was continuously generated in the as-prepared water microdroplets and an apparent equilibrium concentration of ∼3 µM of H2O2 in the presence of a H2O2-consuming reaction can be obtained. Through engineering the geometry of these microdroplets, we further revealed that the generation rates of H2O2 in individual microdroplets were positively proportional to their surface-to-volume ratios. This also allowed us to extract a maximal H2O2 generation rate of 7.7 nmol m-2 min-1 in the presence of a H2O2-consuming reaction and derive the corresponding probability of spontaneous conversion of interfacial H2O into H2O2 for the first time, that is, ∼1 of 65,000 water molecules in 1 s. These findings delivered strong evidence that the spontaneous generation of H2O2 indeed occurs at the surface of microdroplets and provided us with an important starting point to further enhance the yield of H2O2 in water microdroplets for future applications.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38867673

RESUMO

Kidneys from donors with prolonged warm and cold ischemia are prone to post-transplant T cell-mediated rejection (TCMR) due to ischemia-reperfusion injury (IRI). However, the precise mechanisms still remain obscure. Renal tubular epithelial cells (TECs) are the main target during IRI. Meanwhile, we reported previously that murine double minute 2 (MDM2) actively participates in TEC homeostasis during IRI. In this study, we established a murine model of renal IRI and a cell model of hypoxia/reoxygenation by culturing immortalized rat renal proximal tubule cells (NRK-52E) in a hypoxic environment for different time points followed by 24 hours of reoxygenation or incubating NRK-52E cells in a chemical anoxia/recovery environment. We found that during renal IRI, MDM2 expression increased on the membrane of TECs and aggregated mainly on the basolateral side. This process was accompanied by a reduction of a transmembrane protein programmed death-ligand 1 (PD-L1), a co-inhibitory second signal for T cells in TECs. By using mutant plasmids of MDM2 to anchor MDM2 on the cell membrane or nuclei, we found that the upregulation of membrane MDM2 could promote the ubiquitination of PD-L1 and lead to its ubiquitination-proteasome degradation. Lastly, we set up a co-culture system of TECs and CD4+ T cells in vitro; our results revealed that the immunogenicity of TECs was enhanced during IRI. In conclusion, our findings suggest that the increased immunogenicity of TECs during IRI may be related to ubiquitinated degradation of PD-L1 by increased MDM2 on the cell membrane, which consequently results in T cell activation and TCMR.

14.
J Virol ; 97(12): e0105223, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38032197

RESUMO

IMPORTANCE: Human metapneumovirus (hMPV) is a common pathogen causing lower respiratory tract infections worldwide and can develop severe symptoms in high-risk populations such as infants, the elderly, and immunocompromised patients. There are no approved hMPV vaccines or neutralizing antibodies available for therapeutic or prophylactic use. The trimeric hMPV fusion F protein is the major target of neutralizing antibodies in human sera. Understanding the immune recognition of antibodies to hMPV-F antigen will provide critical insights into developing efficacious hMPV monoclonal antibodies and vaccines.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae , Idoso , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Metapneumovirus/fisiologia , Infecções por Paramyxoviridae/imunologia , Proteínas Virais de Fusão , Vacinas Virais/imunologia
15.
FASEB J ; 37(5): e22926, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37052733

RESUMO

Glomerulosclerosis is one of the major histopathologic changes in diabetic kidney diseases (DKD), which is characterized by excessive deposition of extracellular matrix (ECM) in the glomerulus mainly produced by mesangial cells in response to transforming growth factor-ß (TGF-ß) stimuli under diabetic conditions. Despite TGF-ß has been implicated as a major pathogenic factor in the development of diabetic glomerulosclerosis, clinical trials of monoclonal antibodies against TGF-ß failed to demonstrate therapeutic benefits. Thus, developing alternative therapeutic strategies to effectively block the TGF-ß/Smad signaling could be of paramount importance for DKD treatment. Emerging evidence indicates that dysregulation of certain lncRNAs can lead to aberrant activation of TGF-ß/Smad signaling. Herein, we identified a novel lncRNA, named DANCR, which could efficiently function as a negative regulator of TGF-ß/Smad signaling in mesangial cells. Ectopic expression of DANCR could specifically block the activation of TGF-ß/Smad signaling induced by high-glucose or TGF-ß in human renal mesangial cells (HRMCs). Mechanistically, DANCR functions to stabilize nemo-like kinase (NLK) mRNA through interaction with insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), resulting in enhanced phosphorylating on the linker region of activated Smad2/3 in the nucleus. Taken together, our data have uncovered an lncRNA-based regulatory modality of the TGF-ß/Smad signaling and identified DANCR as an endogenous blocker of TGF-ß/Smad signaling in HRMCs, which may represent a potential therapeutic target against the diabetic glomerulosclerosis.


Assuntos
Nefropatias Diabéticas , RNA Longo não Codificante , Humanos , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Matriz Extracelular/metabolismo , Mesângio Glomerular/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Células Mesangiais/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Smad/metabolismo
16.
Protein Expr Purif ; 215: 106406, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37995943

RESUMO

The baculovirus expression system is a powerful and widely used method to generate large quantities of recombinant protein. However, challenges exist in workflows utilizing either liquid baculovirus stocks or the Titerless Infected-Cells Preservation and Scale-Up (TIPS) method, including the time and effort to generate baculoviruses, screen for protein expression and store large numbers of baculovirus stocks. To mitigate these challenges, we have developed a streamlined, hybrid workflow which utilizes high titer liquid virus stocks for rapid plate-based protein expression screening, followed by a TIPS-based scale-up for larger protein production efforts. Additionally, we have automated each step in this screening workflow using a custom robotic system. With these process improvements, we have significantly reduced the time, effort and resources required to manage large baculovirus generation and expression screening campaigns.


Assuntos
Baculoviridae , Triagem , Fluxo de Trabalho , Baculoviridae/genética , Baculoviridae/metabolismo , Proteínas Recombinantes , Vetores Genéticos
18.
Mol Ther ; 31(11): 3337-3354, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37689970

RESUMO

Focal segmental glomerulosclerosis (FSGS) is the most common glomerular disorder causing end-stage renal diseases worldwide. Central to the pathogenesis of FSGS is podocyte dysfunction, which is induced by diverse insults. However, the mechanism governing podocyte injury and repair remains largely unexplored. Asparagine endopeptidase (AEP), a lysosomal protease, regulates substrates by residue-specific cleavage or degradation. We identified the increased AEP expression in the primary proteinuria model which was induced by adriamycin (ADR) to mimic human FSGS. In vivo, global AEP knockout mice manifested increased injury-susceptibility of podocytes in ADR-induced nephropathy (ADRN). Podocyte-specific AEP knockout mice exhibited much more severe glomerular lesions and podocyte injury after ADR injection. In contrast, podocyte-specific augmentation of AEP in mice protected against ADRN. In vitro, knockdown and overexpression of AEP in human podocytes revealed the cytoprotection of AEP as a cytoskeleton regulator. Furthermore, transgelin, an actin-binding protein regulating actin dynamics, was cleaved by AEP, and, as a result, removed its actin-binding regulatory domain. The truncated transgelin regulated podocyte actin dynamics and repressed podocyte hypermotility, compared to the native full-length transgelin. Together, our data reveal a link between lysosomal protease AEP and podocyte cytoskeletal homeostasis, which suggests a potential therapeutic role for AEP in proteinuria disease.


Assuntos
Cisteína Endopeptidases , Glomerulosclerose Segmentar e Focal , Nefropatias , Podócitos , Animais , Humanos , Camundongos , Actinas/genética , Actinas/metabolismo , Doxorrubicina/efeitos adversos , Glomerulosclerose Segmentar e Focal/induzido quimicamente , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/metabolismo , Nefropatias/metabolismo , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Podócitos/metabolismo , Proteinúria/metabolismo , Proteinúria/patologia , Cisteína Endopeptidases/genética
19.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602823

RESUMO

Many cancers evade immune rejection by suppressing major histocompatibility class I (MHC-I) antigen processing and presentation (AgPP). Such cancers do not respond to immune checkpoint inhibitor therapies (ICIT) such as PD-1/PD-L1 [PD-(L)1] blockade. Certain chemotherapeutic drugs augment tumor control by PD-(L)1 inhibitors through potentiation of T-cell priming but whether and how chemotherapy enhances MHC-I-dependent cancer cell recognition by cytotoxic T cells (CTLs) is not entirely clear. We now show that the lysine acetyl transferases p300/CREB binding protein (CBP) control MHC-I AgPPM expression and neoantigen amounts in human cancers. Moreover, we found that two distinct DNA damaging drugs, the platinoid oxaliplatin and the topoisomerase inhibitor mitoxantrone, strongly up-regulate MHC-I AgPP in a manner dependent on activation of nuclear factor kappa B (NF-κB), p300/CBP, and other transcription factors, but independently of autocrine IFNγ signaling. Accordingly, NF-κB and p300 ablations prevent chemotherapy-induced MHC-I AgPP and abrogate rejection of low MHC-I-expressing tumors by reinvigorated CD8+ CTLs. Drugs like oxaliplatin and mitoxantrone may be used to overcome resistance to PD-(L)1 inhibitors in tumors that had "epigenetically down-regulated," but had not permanently lost MHC-I AgPP activity.


Assuntos
Apresentação de Antígeno/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos , Proliferação de Células , Quimioterapia Combinada , Humanos , Imunoterapia/métodos , Camundongos , NF-kappa B/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Oxaliplatina/farmacologia , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Fatores de Transcrição de p300-CBP/genética
20.
Biochem Genet ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767822

RESUMO

To investigate the impact of four single nucleotide polymorphisms (SNPs) of the HIF1α gene and its interaction with Helicobacter pylori (H. pylori) infection on susceptibility to gastric cancer (GC).Logistic regression was used to test the relationship between four SNPs of HIF1α gene and the susceptibility of GC. A generalized multifactor dimensionality reduction (GMDR) model was used to assess the HIF1α gene-H. pylori infection interaction.Logistic regression analysis indicated that both the rs11549465-CT genotype and the T allele were associated with an increased risk of GC, adjusted OR (95% CI) were 1.63 (1.09-2.20) (CT vs. CC) and 1.70 (1.13-2.36) (T vs. C), respectively. We also found that both the rs11549467-A allele and rs11549467-GA genotype were associated with an increased risk of GC, and adjusted OR (95% CI) were 2.21 (1.61-2.86) (GA vs. GG), 2.13 (1.65-2.65) (A vs. G), respectively. However, no statistically significant impact of rs2057482 or rs1957757 on risk of GC was found. The GMDR model indicated a statistically significant two-dimensional model combination (including rs11549467 and H. pylori infection). The selected model had testing balanced accuracy of 0.60 and the best cross-validation consistencies of 10/10 (p = 0.0107). Compared with H. pylori infection negative participants with rs11549467-GG genotype, H. pylori positive participants with the rs11549467-GA genotype had the highest GC risk, the OR (95% CI) was 3.04 (1.98-4.12).The rs11549467-A allele and rs11549467-GA genotype was associated with increased GC risk. Additionally, the gene-environment interaction between HIF-1α-rs11549467 and H. pylori infection was also correlated with an increased risk of GC.

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