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1.
Proc Natl Acad Sci U S A ; 120(20): e2219644120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155882

RESUMO

Emerging evidence suggest that transcription factors play multiple roles in the development of pancreatitis, a necroinflammatory condition lacking specific therapy. Estrogen-related receptor γ (ERRγ), a pleiotropic transcription factor, has been reported to play a vital role in pancreatic acinar cell (PAC) homeostasis. However, the role of ERRγ in PAC dysfunction remains hitherto unknown. Here, we demonstrated in both mice models and human cohorts that pancreatitis is associated with an increase in ERRγ gene expression via activation of STAT3. Acinar-specific ERRγ haploinsufficiency or pharmacological inhibition of ERRγ significantly impaired the progression of pancreatitis both in vitro and in vivo. Using systematic transcriptomic analysis, we identified that voltage-dependent anion channel 1 (VDAC1) acts as a molecular mediator of ERRγ. Mechanistically, we showed that induction of ERRγ in cultured acinar cells and mouse pancreata enhanced VDAC1 expression by directly binding to specific site of the Vdac1 gene promoter and resulted in VDAC1 oligomerization. Notably, VDAC1, whose expression and oligomerization were dependent on ERRγ, modulates mitochondrial Ca2+ and ROS levels. Inhibition of the ERRγ-VDAC1 axis could alleviate mitochondrial Ca2+ accumulation, ROS formation and inhibit progression of pancreatitis. Using two different mouse models of pancreatitis, we showed that pharmacological blockade of ERRγ-VDAC1 pathway has therapeutic benefits in mitigating progression of pancreatitis. Likewise, using PRSS1R122H-Tg mice to mimic human hereditary pancreatitis, we demonstrated that ERRγ inhibitor also alleviated pancreatitis. Our findings highlight the importance of ERRγ in pancreatitis progression and suggests its therapeutic intervention for prevention and treatment of pancreatitis.


Assuntos
Pancreatite Crônica , Canal de Ânion 1 Dependente de Voltagem , Animais , Humanos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Canal de Ânion 1 Dependente de Voltagem/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(30): e2216329120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37478163

RESUMO

To accomplish concerted physiological reactions, nature has diversified functions of a single hormone at at least two primary levels: 1) Different receptors recognize the same hormone, and 2) different cellular effectors couple to the same hormone-receptor pair [R.P. Xiao, Sci STKE 2001, re15 (2001); L. Hein, J. D. Altman, B.K. Kobilka, Nature 402, 181-184 (1999); Y. Daaka, L. M. Luttrell, R. J. Lefkowitz, Nature 390, 88-91 (1997)]. Not only these questions lie in the heart of hormone actions and receptor signaling but also dissecting mechanisms underlying these questions could offer therapeutic routes for refractory diseases, such as kidney injury (KI) or X-linked nephrogenic diabetes insipidus (NDI). Here, we identified that Gs-biased signaling, but not Gi activation downstream of EP4, showed beneficial effects for both KI and NDI treatments. Notably, by solving Cryo-electron microscope (cryo-EM) structures of EP3-Gi, EP4-Gs, and EP4-Gi in complex with endogenous prostaglandin E2 (PGE2)or two synthetic agonists and comparing with PGE2-EP2-Gs structures, we found that unique primary sequences of prostaglandin E2 receptor (EP) receptors and distinct conformational states of the EP4 ligand pocket govern the Gs/Gi transducer coupling selectivity through different structural propagation paths, especially via TM6 and TM7, to generate selective cytoplasmic structural features. In particular, the orientation of the PGE2 ω-chain and two distinct pockets encompassing agonist L902688 of EP4 were differentiated by their Gs/Gi coupling ability. Further, we identified common and distinct features of cytoplasmic side of EP receptors for Gs/Gi coupling and provide a structural basis for selective and biased agonist design of EP4 with therapeutic potential.


Assuntos
Dinoprostona , Transdução de Sinais , Dinoprostona/metabolismo , Transdução de Sinais/fisiologia , Receptores de Prostaglandina/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Hormônios , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo
3.
PLoS Pathog ; 19(9): e1011649, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37695779

RESUMO

Alternative splicing (AS) is a major source of protein diversity in eukaryotes, but less is known about its evolution compared to gene duplication (GD). How AS and GD interact is also largely understudied. By constructing the evolutionary trajectory of the serpin gene PpSerpin-1 (Pteromalus puparum serpin 1) in parasitoids and other insects, we found that both AS and GD jointly contribute to serpin protein diversity. These two processes are negatively correlated and show divergent features in both protein and regulatory sequences. Parasitoid wasps exhibit higher numbers of serpin protein/domains than nonparasitoids, resulting from more GD but less AS in parasitoids. The potential roles of AS and GD in the evolution of parasitoid host-effector genes are discussed. Furthermore, we find that PpSerpin-1 shows an exon expansion of AS compared to other parasitoids, and that several isoforms are involved in the wasp immune response, have been recruited to both wasp venom and larval saliva, and suppress host immunity. Overall, our study provides an example of how a parasitoid serpin gene adapts to parasitism through AS, and sheds light on the differential features of AS and GD in the evolution of insect serpins and their associations with the parasitic life strategy.


Assuntos
Serpinas , Vespas , Animais , Vespas/genética , Serpinas/genética , Processamento Alternativo , Larva/genética , Eucariotos
4.
Exp Cell Res ; 439(1): 114089, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38740166

RESUMO

Nucleus pulposus cells (NPCs) apoptosis and inflammation are the extremely critical factors of intervertebral disc degeneration (IVDD). Nevertheless, the underlying procedure remains mysterious. Macrophage migration inhibitory factor (MIF) is a cytokine that promotes inflammation and has been demonstrated to have a significant impact on apoptosis and inflammation. For this research, we employed a model of NPCs degeneration stimulated by lipopolysaccharides (LPS) and a rat acupuncture IVDD model to examine the role of MIF in vitro and in vivo, respectively. Initially, we verified that there was a significant rise of MIF expression in the NP tissues of individuals with IVDD, as well as in rat models of IVDD. Furthermore, this augmented expression of MIF was similarly evident in degenerated NPCs. Afterwards, it was discovered that ISO-1, a MIF inhibitor, effectively decreased the quantity of cells undergoing apoptosis and inhibited the release of inflammatory molecules (TNF-α, IL-1ß, IL-6). Furthermore, it has been shown that the PI3K/Akt pathway plays a vital part in the regulation of NPCs degeneration by MIF. Ultimately, we showcased that the IVDD process was impacted by the MIF inhibitor in the rat model. In summary, our experimental results substantiate the significant involvement of MIF in the degeneration of NPCs, and inhibiting MIF activity can effectively mitigate IVDD.


Assuntos
Apoptose , Inflamação , Degeneração do Disco Intervertebral , Fatores Inibidores da Migração de Macrófagos , Núcleo Pulposo , Ratos Sprague-Dawley , Animais , Fatores Inibidores da Migração de Macrófagos/antagonistas & inibidores , Fatores Inibidores da Migração de Macrófagos/metabolismo , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/metabolismo , Apoptose/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/patologia , Ratos , Masculino , Humanos , Oxirredutases Intramoleculares/metabolismo , Oxirredutases Intramoleculares/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Feminino , Isoxazóis/farmacologia , Adulto , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Fosfatidilinositol 3-Quinases/metabolismo
5.
Genomics ; 116(2): 110778, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38163575

RESUMO

Ischemia-reperfusion injury (IRI) is an inevitable pathophysiological phenomenon in kidney transplantation. Necroptosis is an undoubtedly important contributing mechanism in renal IRI. We first screened differentially expressed necroptosis-related genes (DENRGs) from public databases. Eight DENRGs were validated by independent datasets and verified by qRT-PCR in a rat IRI model. We used univariate and multivariate Cox regression analyses to establish a prognostic signature, and graft survival analysis was performed. Immune infiltrating landscape analysis and gene set enrichment analysis (GSEA) were performed to understand the underlying mechanisms of graft loss, which suggested that necroptosis may aggravate the immune response, resulting in graft loss. Subsequently, a delayed graft function (DGF) diagnostic signature was constructed using the Least Absolute Shrinkage and Selection Operator (LASSO) and exhibited robust efficacy in validation datasets. After comprehensively analyzing DENRGs during IRI, we successfully constructed a prognostic signature and DGF predictive signature, which may provide clinical insights for kidney transplant.


Assuntos
Transplante de Rim , Ratos , Animais , Transplante de Rim/efeitos adversos , Função Retardada do Enxerto/diagnóstico , Função Retardada do Enxerto/genética , Necroptose , Rim , Sobrevivência de Enxerto/fisiologia
6.
J Am Chem Soc ; 146(8): 5605-5613, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38351743

RESUMO

Carbonyl is highly accessible and acts as an essential functional group in chemical synthesis. However, the direct catalytic deoxygenative functionalization of carbonyl compounds via a putative metal carbene intermediate is a formidable challenge due to the requirement of a high activation energy for the cleavage of strong C═O double bonds. Here, we report a class of bench stable and readily available Cp*Mo(II)-complexes as efficient deoxygenation catalysts that could catalyze the direct intermolecular deoxygenative coupling of carbonyl compounds with alkynes. Enabled by this powerful Cp*Mo(II)-catalyst, various valuable heteroarenes (10 different classes) were obtained in generally good yields and remarkable chemo- and regioselectivities. Mechanistic studies suggested that this reaction might proceed via a sequence of C═O double bonds cleavage, carbene-alkyne metathesis, cyclization, and aromatization processes. This strategy not only provided a general catalytic platform for the rapid preparation of heteroarenes but also opened a new window for the applications of Cp*Mo(II)-catalysts in organic synthesis.

7.
J Hepatol ; 81(1): 120-134, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38428643

RESUMO

BACKGROUND & AIMS: The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aimed to evaluate the role of PTEN in the pathogenesis of eCCA and identify novel therapeutic targets for this disease. METHODS: The Pten gene was genetically deleted using the Cre-loxp system in biliary epithelial cells. The pathologies were evaluated both macroscopically and histologically. The characteristics were further analyzed by immunohistochemistry, reverse-transcription PCR, cell culture, and RNA sequencing. Some features were compared to those in human eCCA samples. Further mechanistic studies utilized the conditional knockout of Trp53 and Aurora kinase A (Aurka) genes. We also tested the effectiveness of an Aurka inhibitor. RESULTS: We observed that genetic deletion of the Pten gene in the extrahepatic biliary epithelium and peri-ductal glands initiated sclerosing cholangitis-like lesions in mice, resulting in enlarged and distorted extrahepatic bile ducts in mice as early as 1 month after birth. Histologically, these lesions exhibited increased epithelial proliferation, inflammatory cell infiltration, and fibrosis. With aging, the lesions progressed from low-grade dysplasia to invasive carcinoma. Trp53 inactivation further accelerated disease progression, potentially by downregulating senescence. Further mechanistic studies showed that both human and mouse eCCA showed high expression of AURKA. Notably, the genetic deletion of Aurka completely eliminated Pten deficiency-induced extrahepatic bile duct lesions. Furthermore, pharmacological inhibition of Aurka alleviated disease progression. CONCLUSIONS: Pten deficiency in extrahepatic cholangiocytes and peribiliary glands led to a cholangitis-to-cholangiocarcinoma continuum that was dependent on Aurka. These findings offer new insights into preventive and therapeutic interventions for extrahepatic CCA. IMPACT AND IMPLICATIONS: The aberrant PTEN-PI3K-AKT signaling pathway is commonly observed in human extrahepatic cholangiocarcinoma (eCCA), a disease with a poor prognosis. In our study, we developed a mouse model mimicking cholangitis to eCCA progression by conditionally deleting the Pten gene via Pdx1-Cre in epithelial cells and peribiliary glands of the extrahepatic biliary duct. The conditional Pten deletion in these cells led to cholangitis, which gradually advanced to dysplasia, ultimately resulting in eCCA. The loss of Pten heightened Akt signaling, cell proliferation, inflammation, fibrosis, DNA damage, epigenetic signaling, epithelial-mesenchymal transition, cell dysplasia, and cellular senescence. Genetic deletion or pharmacological inhibition of Aurka successfully halted disease progression. This model will be valuable for testing novel therapies and unraveling the mechanisms of eCCA tumorigenesis.


Assuntos
Aurora Quinase A , Neoplasias dos Ductos Biliares , Colangiocarcinoma , PTEN Fosfo-Hidrolase , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Animais , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Colangiocarcinoma/etiologia , Colangiocarcinoma/patologia , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Camundongos , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/etiologia , Neoplasias dos Ductos Biliares/metabolismo , Humanos , Camundongos Knockout , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ductos Biliares Extra-Hepáticos/patologia , Modelos Animais de Doenças , Colangite/patologia , Colangite/etiologia , Colangite/metabolismo , Colangite/genética , Transdução de Sinais
8.
Am J Physiol Gastrointest Liver Physiol ; 326(4): G473-G481, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38410866

RESUMO

Genetically engineered mouse models play a pivotal role in the modeling of diseases, exploration of gene functions, and the development of novel therapies. In recent years, clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated genome editing technology has revolutionized the process of developing such models by enabling precise genome modifications of the multiple interested genes simultaneously. Following genome editing, an efficient genotyping methodology is crucial for subsequent characterization. However, current genotyping methods are laborious, time-consuming, and costly. Here, using targeting the mouse trypsinogen genes as an example, we introduced common applications of CRISPR-Cas9 editing and a streamlined cost-effective genotyping workflow for CRISPR-edited mouse models, in which Sanger sequencing is required only at the initial steps. In the F0 mice, we focused on identifying the presence of positive editing by PCR followed by Sanger sequencing without the need to know the exact sequences, simplifying the initial screening. In the F1 mice, Sanger sequencing and algorithms decoding were used to identify the precise editing. Once the edited sequence was established, a simple and effective genotyping strategy was established to distinguish homozygous and heterozygous status by PCR from tail DNA. The genotyping workflow applies to deletions as small as one nucleotide, multiple-gene knockout, and knockin studies. This simplified, efficient, and cost-effective genotyping shall be instructive to new investigators who are unfamiliar with characterizing CRISPR-Cas9-edited mouse strains.NEW & NOTEWORTHY This study presents a streamlined, cost-effective genotyping workflow for clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) edited mouse models, focusing on trypsinogen genes. It simplifies initial F0 mouse screening using PCR and Sanger sequencing without needing exact sequences. For F1 mice, precise editing is identified through Sanger sequencing and algorithm decoding. The workflow includes a novel PCR strategy for distinguishing homozygous and heterozygous statuses in subsequent generations, effective for small deletions, multiple-gene knockouts, and knockins.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Camundongos , Animais , Edição de Genes/métodos , Proteína 9 Associada à CRISPR/genética , Genótipo , Tripsinogênio , Fluxo de Trabalho
9.
Am J Physiol Gastrointest Liver Physiol ; 326(5): G495-G503, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469630

RESUMO

Tissue-specific gene manipulations are widely used in genetically engineered mouse models. A single recombinase system, such as the one using Alb-Cre, has been commonly used for liver-specific genetic manipulations. However, most diseases are complex, involving multiple genetic changes and various cell types. A dual recombinase system is required for conditionally modifying different genes sequentially in the same cell or inducing genetic changes in different cell types within the same organism. A FlpO cDNA was inserted between the last exon and 3'-UTR of the mouse albumin gene in a bacterial artificial chromosome (BAC-Alb-FlpO). The founders were crossed with various reporter mice to examine the efficiency of recombination. Liver cancer tumorigenesis was investigated by crossing the FlpO mice with FSF-KrasG12D mice and p53frt mice (KPF mice). BAC-Alb-FlpO mice exhibited highly efficient recombination capability in both hepatocytes and intrahepatic cholangiocytes. No recombination was observed in the duodenum and pancreatic cells. BAC-Alb-FlpO-mediated liver-specific expression of mutant KrasG12D and conditional deletion of p53 gene caused the development of liver cancer. Remarkably, liver cancer in these KPF mice manifested a distinctive mixed hepatocellular carcinoma and cholangiocarcinoma phenotype. A highly efficient and liver-specific BAC-Alb-FlpO mouse model was developed. In combination with other Cre lines, different genes can be manipulated sequentially in the same cell, or distinct genetic changes can be induced in different cell types of the same organism.NEW & NOTEWORTHY A liver-specific Alb-FlpO mouse line was generated. By coupling it with other existing CreERT or Cre lines, the dual recombinase approach can enable sequential gene modifications within the same cell or across various cell types in an organism for liver research through temporal and spatial gene manipulations.


Assuntos
Neoplasias Hepáticas , Proteínas Proto-Oncogênicas p21(ras) , Camundongos , Animais , Camundongos Transgênicos , Proteínas Proto-Oncogênicas p21(ras)/genética , Albuminas/genética , Recombinases/genética , Recombinação Genética , Neoplasias Hepáticas/genética , Integrases/genética
10.
Stem Cells ; 41(2): 169-183, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36512434

RESUMO

The apoptosis of grafted islets is an urgent problem due to the high rate of islet loss soon after transplantation. MicroRNA-21-5p (miR-21-5p) is an essential mediator of bone marrow mesenchymal stem cells-derived exosomes (BMSCs-Exo) during anti-apoptosis, but its effect and the underlying molecular mechanism in islet transplantation remain partially understood. Here, we found that miR-21-5p could be delivered to islet cells via BMSCs-Exo. Subsequently, we demonstrated that miR-21-5p overexpression reduced apoptosis in islets and INS-1 cells, whereas miR-21-5p inhibition enhanced apoptosis. A mechanistic analysis involving RNA sequencing and bioinformatic analysis was performed to determine the interaction between miR-21-5p and its target gene programmed cell death 4 (PDCD4), which was further verified by a dual luciferase assay. In vivo, the grafted islets overexpressing miR-21-5p showed a higher survival rate, better insulin secretion function, and a lower apoptosis rate. In conclusion, these results demonstrated that miR­21­5p from BMSCs-Exo protects against the apoptosis of grafted islets by inhibiting PDCD4 expression. Hence, miR-21-5p can be used as a cell-free therapeutic agent to minimize ß-cell apoptosis at the early stage of islet transplantation.


Assuntos
Exossomos , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Células-Tronco Mesenquimais , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose/genética , Ilhotas Pancreáticas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Exossomos/metabolismo
11.
Cell Commun Signal ; 22(1): 300, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816763

RESUMO

Optimizing the efficiency of definitive endoderm (DE) differentiation is necessary for the generation of diverse organ-like structures. In this study, we used the small molecule inhibitor saracatinib (SAR) to enhance DE differentiation of human embryonic stem cells and induced pluripotent stem cells. SAR significantly improved DE differentiation efficiency at low concentrations. The interaction between SAR and Focal Adhesion Kinase (FAK) was explored through RNA-seq and molecular docking simulations, which further supported the inhibition of DE differentiation by p-FAK overexpression in SAR-treated cells. In addition, we found that SAR inhibited the nuclear translocation of Yes-associated protein (YAP), a downstream effector of FAK, which promoted DE differentiation. Moreover, the addition of SAR enabled a significant reduction in activin A (AA) from 50 to 10 ng/mL without compromising DE differentiation efficiency. For induction of the pancreatic lineage, 10 ng/ml AA combined with SAR at the DE differentiation stage yielded a comparative number of PDX1+/NKX6.1+ pancreatic progenitor cells to those obtained by 50 ng/ml AA treatment. Our study highlights SAR as a potential modulator that facilitates the cost-effective generation of DE cells and provides insight into the orchestration of cell fate determination.


Assuntos
Benzodioxóis , Diferenciação Celular , Endoderma , Quinazolinas , Transdução de Sinais , Humanos , Diferenciação Celular/efeitos dos fármacos , Endoderma/efeitos dos fármacos , Endoderma/citologia , Endoderma/metabolismo , Benzodioxóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Quinazolinas/farmacologia , Fatores de Transcrição/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Sinalização YAP/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Ativinas/metabolismo , Simulação de Acoplamento Molecular
12.
Langmuir ; 40(16): 8593-8607, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38604806

RESUMO

Understanding the adsorption mechanism and precisely predicting the thermodynamic adsorption properties of methane at high pressure are crucial while very challenging for shale gas development. In this study, we demonstrated that the Langmuir adsorption model combining with different empirical methods to determine the adsorption phase density makes the calculated isothermal adsorption heat violate Henry's law at low pressure. For instance, the isothermal adsorption heat calculated by the Langmuir-Freundlich model contradicts Henry's law when the absolute adsorption quantity is zero. Given the current challenge in accurately calculating the adsorption phase density, it is necessary to impose constraints on the parameters of the adsorption model by adhering to Henry's law to maintain thermodynamic consistency. We found that the adsorption phase volume of methane molecules lies between the micropore volume and the total pore volume when shale adsorption reaches saturation. The adsorption mechanism involves not only filling micropores but also monolayer adsorption in meso-macro pores. The high-energy adsorption sites for methane are primarily concentrated in organic matter, while within these methane adsorption areas in shale, the high-energy adsorption sites for water are mainly located in kaolinite within clay minerals. The zero-pressure heat of adsorption is a temperature-independent thermodynamic index, yet it is influenced by the water content. It can therefore be selected as a quantitative measure to evaluate the impact of methane adsorption on water.

13.
Pharmacol Res ; 203: 107159, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554790

RESUMO

Encapsulated cell technology (ECT) is a targeted delivery method that uses the genetically engineered cells in semipermeable polymer capsules to deliver cytokines. Thus far, ECT has been extensively utilized in pharmacologic research, and shows enormous potentials in the treatment of posterior segment diseases. Due to the biological barriers within the eyeball, it is difficult to attain effective therapeutic concentration in the posterior segment through topical administration of drug molecules. Encouragingly, therapeutic cytokines provided by ECT can cross these biological barriers and achieve sustained release at the desired location. The encapsulation system uses permeable materials that allow growth factors and cytokines to diffuse efficiently into retinal tissue. Moreover, the ECT based treatment can be terminated timely when we need to retrieve the implant, which makes the therapy reversible and provides a safer alternative for intraocular gene therapy. Meanwhile, we also place special emphasis on optimizing encapsulation materials and enhancing preservation techniques to achieve the stable release of growth factors and cytokines in the eyeball. This technology holds great promise for the treatment of patients with dry AMD, RP, glaucoma and MacTel. These findings would enrich our understandings of ECT and promote its future applications in treatment of degenerative retinopathy. This review comprises articles evaluating the exactness of artificial intelligence-based formulas published from 2000 to March 2024. The papers were identified by a literature search of various databases (PubMed/MEDLINE, Google Scholar, Cochrane Library and Web of Science).


Assuntos
Citocinas , Oftalmopatias , Humanos , Citocinas/metabolismo , Animais , Oftalmopatias/terapia , Oftalmopatias/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Encapsulamento de Células/métodos
14.
Phys Chem Chem Phys ; 26(21): 15717-15732, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38767249

RESUMO

This study examines how a deionized water droplet behaves when it centrally collides with a liquid film containing TiO2 nanoparticles at low impact velocities, aiming to understand how nanoparticles affect droplet spreading, in particular its maximum spreading diameter. Typically, we found that both the spreading velocity and dynamic contact angle of the droplet would be similarly affected by increasing TiO2 nanoparticle concentration. During retraction, the droplet's dimensionless spreading diameter oscillates, with more pronounced oscillations at higher nanoparticle concentrations. Moreover, both the droplet's maximum dimensionless rebound height and dynamic contact angle show similar trends with increasing TiO2 nanoparticle concentration. Interestingly, we proved that the influence of the solid-liquid interaction (Stokes force) on the fluid during the spreading process accounts for less than 2% of the surface energy when the droplet reaches its maximum spreading diameter, indicating a negligible effect on droplet spreading. We hypothesize that the droplet's initial energy is fully converted into surface energy and viscous dissipation at maximum spreading diameter, which involves viscous dissipation both between the fluid and the solid wall surface and the fluid and solid particle surface. Based on this, we developed a model for predicting the droplet's maximum spreading diameter that includes parameters associated with the solid particles. Compared to models in the literature that do not consider the effect of solid particles, our model aligns more closely with experimental data. The results indicate that adding solid particles leads to increased viscous dissipation, which in turn reduces the droplet's maximum spreading diameter.

15.
Environ Res ; 256: 119245, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810821

RESUMO

Microalgae have been renowned as the most promising energy organism with significant potential in carbon fixation. In the large-scale cultivation of microalgae, the 3D porous substrate with higher specific surface area is favorable to microalgae adsorption and biofilm formation, whereas difficult for biofilm detachment and microalgae harvesting. To solve this contradiction, N-isopropylacrylamide, a temperature-responsive gels material, was grafted onto the inner surface of the 3D porous substrate to form temperature-controllable interface wettability. The interfacial free energy between microalgae biofilm and the substrates increased from -63.02 mJ/m2 to -31.89 mJ/m2 when temperature was lowered from 32 °C to 17 °C, weakening the adsorption capacity of cells to the surface, and making the biofilm detachment ratio increased to 50.8%. When further cooling the environmental temperature to 4 °C, the detachment capability of microalgae biofilm kept growing. 91.6% of the cells in the biofilm were harvesting from the 3D porous substrate. And the biofilm detached rate was up to 19.84 g/m2/h, realizing the temperature-controlled microalgae biofilm harvesting. But, microalgae growth results in the secretion of extracellular polymeric substances (EPS), which enhanced biofilm adhesion and made cell detachment more difficult. Thus, ultrasonic vibration was used to reinforce biofilm detachment. With the help of ultrasonic vibration, microalgae biofilm detached rate increased by 143.45% to 41.07 g/m2/h. These findings provide a solid foundation for further development of microalgae biofilm detachment and harvesting technology.


Assuntos
Biofilmes , Géis , Microalgas , Temperatura , Biofilmes/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Porosidade , Géis/química , Acrilamidas/química
16.
J Nanobiotechnology ; 22(1): 301, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38816771

RESUMO

Intervertebral disc degeneration (IVDD) is the primary factor contributing to low back pain (LBP). Unlike elderly patients, many young IVDD patients usually have a history of trauma or long-term abnormal stress, which may lead to local inflammatory reaction causing by immune cells, and ultimately accelerates degeneration. Research has shown the significance of M1-type macrophages in IVDD; nevertheless, the precise mechanism and the route by which it influences the function of nucleus pulposus cell (NPC) remain unknown. Utilizing a rat acupuncture IVDD model and an NPC degeneration model induced by lipopolysaccharide (LPS), we investigated the function of M1 macrophage-derived exosomes (M1-Exos) in IVDD both in vivo and in vitro in this study. We found that M1-Exos enhanced LPS-induced NPC senescence, increased the number of SA-ß-gal-positive cells, blocked the cell cycle, and promoted the activation of P21 and P53. M1-Exos derived from supernatant pretreated with the exosome inhibitor GW4869 reversed this result in vivo and in vitro. RNA-seq showed that Lipocalin2 (LCN2) was enriched in M1-Exos and targeted the NF-κB pathway. The quantity of SA-ß-gal-positive cells was significantly reduced with the inhibition of LCN2, and the expression of P21 and P53 in NPCs was decreased. The same results were obtained in the acupuncture-induced IVDD model. In addition, inhibition of LCN2 promotes the expression of type II collagen (Col-2) and inhibits the expression of matrix metalloproteinase 13 (MMP13), thereby restoring the equilibrium of metabolism inside the extracellular matrix (ECM) in vitro and in vivo. In addition, the NF-κB pathway is crucial for regulating M1-Exo-mediated NPC senescence. After the addition of M1-Exos to LPS-treated NPCs, p-p65 activity was significantly activated, while si-LCN2 treatment significantly inhibited p-p65 activity. Therefore, this paper demonstrates that M1 macrophage-derived exosomes have the ability to deliver LCN2, which activates the NF-κB signaling pathway, and exacerbates IVDD by accelerating NPC senescence. This may shed new light on the mechanism of IVDD and bring a fresh approach to IVDD therapy.


Assuntos
Senescência Celular , Exossomos , Degeneração do Disco Intervertebral , Lipocalina-2 , Macrófagos , NF-kappa B , Núcleo Pulposo , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Exossomos/metabolismo , Núcleo Pulposo/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Lipocalina-2/metabolismo , Lipocalina-2/genética , Ratos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Lipopolissacarídeos/farmacologia , Modelos Animais de Doenças
17.
Biochem J ; 480(20): 1659-1674, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37818922

RESUMO

Mechanotransduction and contact inhibition (CI) control gene expression to regulate proliferation, differentiation, and even tumorigenesis of cells. However, their downstream trans-acting factors (TAFs) are not well known due to a lack of a high-throughput method to quantitatively detect them. Here, we developed a method to identify TAFs on the cis-acting sequences that reside in open chromatin or DNaseI-hypersensitive sites (DHSs) and to detect nucleocytoplasmic shuttling TAFs using computational and experimental screening. The DHS-proteomics revealed over 1000 potential mechanosensing TAFs and UBE2A/B (Ubiquitin-conjugating enzyme E2 A) was experimentally identified as a force- and CI-dependent nucleocytoplasmic shuttling TAF. We found that translocation of YAP/TAZ and UBE2A/B are distinctively regulated by inhibition of myosin contraction, actin-polymerization, and CI depending on cell types. Next-generation sequence analysis revealed many downstream genes including YAP are transcriptionally regulated by ubiquitination of histone by UBE2A/B. Our results suggested a YAP-independent mechanotransduction and CI pathway mediated by UBE2A/B.


Assuntos
Transativadores , Enzimas de Conjugação de Ubiquitina , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Transativadores/genética , Mecanotransdução Celular , Inibição de Contato , Ubiquitinação , Enzimas Ativadoras de Ubiquitina/genética
18.
J Am Chem Soc ; 145(5): 2765-2772, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36626166

RESUMO

The catalytic asymmetric cyclopropanation reaction of alkenes with diazo compounds is a direct and powerful method to construct chiral cyclopropanes that are essential to drug discovery. However, diazo compounds are potentially explosive and often require hazardous reagents for their preparation. Here, we report on the use of 1,2-dicarbonyl compounds as safe and readily available surrogates for diazo compounds in the direct catalytic asymmetric deoxygenative cyclopropanation reaction. Enabled by a class of simple and readily accessible chiral salen-Mo catalysts, the reaction proceeded with generally good enantioselectivities and yields toward a wide range of substrates (80 examples). Preliminary mechanistic studies suggested that the proposed µ-oxo bridged dinuclear Mo(III)-species was the catalytically active species. This strategy not only provides a promising route for the synthesis of chiral cyclopropanes but also opens a new window for the potential applications of chiral salen-Mo complexes in asymmetric catalysis.

19.
Crit Rev Eukaryot Gene Expr ; 33(8): 57-75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37606164

RESUMO

High-temperature requirement factor A3 (HTRA3), a member of the HTRA protein family, is closely associated with apoptosis and plays a crucial role in controlling signal transmission and cancer development. However, the regulatory pathways of HTRA3 in tumors are not fully understood, necessitating a comprehensive analysis of HTRA3 in cancers. In this study, we conducted a multi-omics analysis of HTRA3 in pan-cancer using data from various databases including TCGA, cBioPortal, GeneMANIA, DAVID, TIMER2.0, SangerBox, and RNAactDrug. Our analysis included gene expression, survival prognosis, diagnostic value, mutation, gene-gene interaction, enrichment analysis, and drug sensitivity analysis. We found that HTRA3 is aberrantly expressed in a variety of cancers and significantly correlates with diagnosis, prognosis, TMB, MSI, immune checkpoint (ICP) genes, and drug sensitivity in various cancer types. HTRA3 is involved in a variety of cancer pathways, particularly extracellular matrix (ECM) alterations, and has a potential role in epithelial-mesenchymal transition (EMT). HTRA3 expression is positively correlated with the abundance of cancer-associated fibroblasts (CAFs) and endothelial cells in the tumor microenvironment, and is also positively correlated with immune scores, stromal scores, and ESTIMATE scores in multiple cancers. HTRA3 is often overexpressed in cancer and is associated with poor prognosis and regulation of the tumor's immune response. Therefore, it may serve as a novel biomarker for tumor diagnosis and treatment.


Assuntos
Células Endoteliais , Neoplasias , Humanos , Prognóstico , Neoplasias/diagnóstico , Neoplasias/genética , Temperatura , Apoptose , Microambiente Tumoral/genética , Serina Endopeptidases/genética
20.
Opt Express ; 31(19): 31447-31462, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710664

RESUMO

Underwater wireless optical communications (UWOC) is a promising technology to construct underwater Internet of Things. In spite of the great progress in high-speed communication having been realized, scattering, absorption, and turbulence result in an unreliable underwater channel for reliable data transmissions. In this paper, we propose a time-reversal (TR) waveform design technique in UWOC systems for intersymbol interference (ISI) reduction. Due to the optical scattering properties in the ocean, the dispersive channel impulse response (CIR) of UWOC is caused by the multi-path effects of numerous scattered and delayed photons. Based on the analysis and simulation results shown in this paper, the TR waveform is well-suited for UWOC systems. After transmitting the TR waveform, the equivalent channel becomes symmetric, which is easily equalized to mitigate the ISI. Since only the intensity modulation and direct detection can be used for UWOC systems, we derive the UWOC channel as a combination of an exponential bias with the random scattering effects. From the numerical results shown in this work, a phenomenon called the squeezing effect is found, which explains the influence of non-negative channels for the TR waveform design in the UWOC system. Due to the squeezing effect, an equalizer is necessarily applied. With the help of TR waveforms, the bit error rate in the tested environment is greatly better than the case of not using the TR waveform.

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