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1.
Adv Sci (Weinh) ; : e2308890, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004913

RESUMO

Interferons (IFNs) activate JAK-STAT pathways to induce downstream effector genes for host defense against invaded pathogens and tumors. Here both type I (ß) and II (γ) IFNs are shown that can activate the transcription factor IRF3 in parallel with STAT1. IRF3-deficiency impairs transcription of a subset of downstream effector genes induced by IFN-ß and IFN-γ. Mechanistically, IFN-induced activation of IRF3 is dependent on the cGAS-STING-TBK1 axis. Both IFN-ß and IFN-γ cause mitochondrial DNA release into the cytosol. In addition, IFNs induce JAK1-mediated tyrosine phosphorylation of cGAS at Y214/Y215, which is essential for its DNA binding activity and signaling. Furthermore, deficiency of cGAS, STING, or IRF3 impairs IFN-ß- or IFN-γ-mediated antiviral and antitumor activities. The findings reveal a novel IRF3 activation pathway parallel with the canonical STAT1/2 activation pathways triggered by IFNs and provide an explanation for the pleiotropic roles of the cGAS-STING-IRF3 axis in host defense.

2.
Molecules ; 29(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998928

RESUMO

In conventional lithium-ion batteries (LIBs), the active lithium from the lithium-containing cathode is consumed by the formation of a solid electrolyte interface (SEI) at the anode during the first charge, resulting in irreversible capacity loss. Prelithiation additives can provide additional active lithium to effectively compensate for lithium loss. Lithium oxalate is regarded as a promising ideal cathode prelithiation agent; however, the electrochemical decomposition of lithium oxalate is challenging. In this work, a hollow and porous composite microsphere was prepared using a mixture of lithium oxalate, Ketjen Black and transition metal oxide catalyst, and the formulation was optimized. Owing to the compositional and structural merits, the decomposition voltage of lithium oxalate in the microsphere was reduced to 3.93 V; when being used as an additive, there is no noticeable side effect on the performance of the cathode material. With 4.2% of such an additive, the first discharge capacity of the LiFePO4‖graphite full cell increases from 139.1 to 151.9 mAh g-1, and the coulombic efficiency increases from 88.1% to 96.3%; it also facilitates the formation of a superior SEI, leading to enhanced cycling stability. This work provides an optimized formula for developing an efficient prelithiation agent for LIBs.

3.
Mol Inform ; : e202300336, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39031899

RESUMO

Kinases, a class of enzymes controlling various substrates phosphorylation, are pivotal in both physiological and pathological processes. Although their conserved ATP binding pockets pose challenges for achieving selectivity, this feature offers opportunities for drug repositioning of kinase inhibitors (KIs). This study presents a cost-effective in silico prediction of KIs drug repositioning via analyzing cross-docking results. We established the KIs database (278 unique KIs, 1834 bioactivity data points) and kinases database (357 kinase structures categorized by the DFG motif) for carrying out cross-docking. Comparative analysis of the docking scores and reported experimental bioactivity revealed that the Atypical, TK, and TKL superfamilies are suitable for drug repositioning. Among these kinase superfamilies, Olverematinib, Lapatinib, and Abemaciclib displayed enzymatic activity in our focused AKT-PI3K-mTOR pathway with IC50 values of 3.3, 3.2 and 5.8 µM. Further cell assays showed IC50 values of 0.2, 1.2 and 0.6 µM in tumor cells. The consistent result between prediction and validation demonstrated that repositioning KIs via in silico method is feasible.

5.
Sci Total Environ ; 927: 172376, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604376

RESUMO

Biofilms are widely used and play important roles in biological processes. Low temperature of wastewater inhibits the development of biofilms derived from wastewater activated sludge. However, the specific mechanism of temperature on biofilm development is still unclear. This study explored the mechanism of temperature on biofilm development and found a feasible method to enhance biofilm development at low temperature. The amount of biofilm development decreased by approximately 66 % and 55 % at 4 °C and 15 °C, respectively, as compared to 28 °C. The cyclic dimeric guanosine monophosphate (c-di-GMP) concentration also decreased at low temperature and was positively correlated with extracellular polymeric substance (EPS) content, formation, and adhesion strength. Microbial community results showed that low temperature inhibited the normal survival of most microorganisms, but promoted the growth of some psychrophile bacteria like Sporosarcina, Caldilineaceae, Gemmataceae, Anaerolineaceae and Acidobacteriota. Further analysis of functional genes demonstrated that the abundance of functional genes related to the synthesis of c-di-GMP (K18968, K18967 and K13590) decreased at low temperature. Subsequently, the addition of exogenous spermidine increased the level of intracellular c-di-GMP and alleviated the inhibition effect of low temperature on biofilm development. Therefore, the possible mechanism of low temperature on biofilm development could be the inhibition of the microorganism activity and reduction of the communication level between cells, which is the closely related to the EPS content, formation, and adhesion strength. The enhancement of c-di-GMP level through the exogenous addition of spermidine provides an alternative strategy to enhance biofilm development at low temperatures. The results of this study enhance the understanding of the influence of temperature on biofilm development and provide possible strategies for enhancing biofilm development at low temperatures.


Assuntos
Bactérias , Biofilmes , GMP Cíclico , Fenômenos Fisiológicos Bacterianos , Temperatura Baixa , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Matriz Extracelular de Substâncias Poliméricas , Águas Residuárias/microbiologia
6.
Urology ; 189: 70-76, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38490277

RESUMO

OBJECTIVE: Benign prostatic hyperplasia (BPH) management has evolved from transurethral resection of the prostate (TURP) to holmium laser enucleation of the prostate (HoLEP). Recent innovation introduces Moses™ technology in holmium lasers, with the Lumenis Pulse™ system. METHODS: To compare Moses-augmented HoLEP (MoLEP) to non-Moses HoLEP in terms of enucleation efficiency, hemostasis, and applicability in day surgery settings. A single-blind, prospective, parallel randomized controlled trial was conducted in Shanghai, China, from March to December 2022. Ethical approval (SK2020-038) was obtained, and 100 consenting men over 50 with BPH indications were randomized (1:1) into MoLEP and HoLEP groups. Surgical procedures were standardized, and outcomes were assessed by blinded analysts. RESULTS: Data from 80 participants (38 MoLEP, 42 HoLEP) were analyzed. Baseline characteristics were comparable. MoLEP demonstrated superior enucleation efficiency (3.5±0.8 g/min) and shorter enucleation time (22.5±7.6 minutes) compared to HoLEP, although not statistically significant. MoLEP achieved hemostasis in less time (6.6±4.2 minutes) than HoLEP (11.2±5.1 minutes). Postoperative care demands varied, with MoLEP requiring less bladder irrigation. MoLEP exhibited a shorter average catheterization time (1.3±0.1 days) and reduced hospitalization compared to HoLEP. Both groups showed significant postoperative improvements in functional outcomes. CONCLUSION: While statistical significance was not achieved in certain outcome measures, MoLEP exhibited potential advantages in postoperative care demands, shorter catheterization time, and reduced hospitalization, suggesting its feasibility and safety in day surgery settings. Postoperative functional outcomes improved significantly in both groups.


Assuntos
Lasers de Estado Sólido , Prostatectomia , Hiperplasia Prostática , Humanos , Masculino , Lasers de Estado Sólido/uso terapêutico , Hiperplasia Prostática/cirurgia , Idoso , Método Simples-Cego , Estudos Prospectivos , Pessoa de Meia-Idade , Prostatectomia/métodos , Resultado do Tratamento , Terapia a Laser/métodos , Duração da Cirurgia , Procedimentos Cirúrgicos Ambulatórios/métodos
7.
J Med Chem ; 67(5): 4194-4224, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38442261

RESUMO

Retinoic acid receptor-related orphan receptor γ (RORγ) acts as a crucial transcription factor in Th17 cells and is involved in diverse autoimmune disorders. RORγ allosteric inhibitors have gained significant research focus as a novel strategy to inhibit RORγ transcriptional activity. Leveraging the high affinity and selectivity of RORγ allosteric inhibitor MRL-871 (1), this study presents the design, synthesis, and characterization of 11 allosteric fluorescent probes. Utilizing the preferred probe 12h, we established an efficient and cost-effective fluorescence polarization-based affinity assay for screening RORγ allosteric binders. By employing virtual screening in conjunction with this assay, 10 novel RORγ allosteric inhibitors were identified. The initial SAR studies focusing on the hit compound G381-0087 are also presented. The encouraging outcomes indicate that probe 12h possesses the potential to function as a powerful tool in facilitating the exploration of RORγ allosteric inhibitors and furthering understanding of RORγ function.


Assuntos
Corantes Fluorescentes , Células Th17 , Corantes Fluorescentes/farmacologia , Fatores de Transcrição , Regulação da Expressão Gênica , Polarização de Fluorescência , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo
8.
J Med Chem ; 67(6): 4346-4375, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38484122

RESUMO

Over the past decades, the role of rearranged during transfection (RET) alterations in tumorigenesis has been firmly established. RET kinase inhibition is an essential therapeutic target in patients with RET-altered cancers. In clinical practice, initial efficacy can be achieved in patients through the utilization of multikinase inhibitors (MKIs) with RET inhibitory activity. However, the effectiveness of these MKIs is impeded by the adverse events associated with off-target effects. Recently, many RET-selective inhibitors, characterized by heightened specificity and potency, have been developed, representing a substantial breakthrough in the field of RET precision oncology. This Perspective focuses on the contemporary understanding of RET mutations, recent advancements in next-generation RET inhibitors, and the challenges associated with resistance to RET inhibitors. It provides valuable insights for the development of next-generation MKIs and selective RET inhibitors.


Assuntos
Neoplasias Pulmonares , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas c-ret/genética , Medicina de Precisão , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Mutação , Neoplasias Pulmonares/tratamento farmacológico
10.
Mol Cancer Ther ; 23(7): 1043-1056, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38346939

RESUMO

Many patients with colorectal cancer do not respond to immune checkpoint blockade (ICB) therapy, highlighting the urgent need to understand tumor resistance mechanisms. Recently, the link between the IFNγ signaling pathway integrity and ICB resistance in the colorectal cancer tumor microenvironment has been revealed. The immunosuppressive microenvironment poses a significant challenge to antitumor immunity in colorectal cancer development. Tumor-associated neutrophils found in tumor tissues exhibit an immunosuppressive phenotype and are associated with colorectal cancer patient prognosis. Neutrophil extracellular traps (NET), DNA meshes containing cytotoxic enzymes released into the extracellular space, may be promising therapeutic targets in cancer. This study showed increased NETs in tumor tissues and peripheral neutrophils of high levels of microsatellite instability (MSI-H) patients with colorectal cancer compared with microsatellite stable (MSS) patients with colorectal cancer. IFNγ response genes were enriched in MSI-H patients with colorectal cancer compared with patients with MSS colorectal cancer. Co-culturing neutrophils with MSI-H colorectal cancer cell lines induced more NET formation and higher cellular apoptosis than MSS colorectal cancer cell lines. IFNγ treatment induced more NET formation and apoptosis in MSS colorectal cancer cell lines. Using subcutaneous or orthotopic CT-26 (MSS) tumor-bearing mice models, IFNγ reduced tumor size and enhanced PD-1 antibody-induced tumor-killing activity, accompanied by upregulated NETs and cellular apoptosis. These findings suggest that IFNγ could be a therapeutic strategy for MSS colorectal cancer.


Assuntos
Neoplasias Colorretais , Armadilhas Extracelulares , Interferon gama , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Armadilhas Extracelulares/metabolismo , Animais , Camundongos , Interferon gama/metabolismo , Interferon gama/farmacologia , Feminino , Instabilidade de Microssatélites , Neutrófilos/metabolismo , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Masculino , Microambiente Tumoral/imunologia , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Bioorg Med Chem ; 100: 117631, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38330848

RESUMO

Acute myeloid leukemia (AML) is the most common type of blood cancer and has been strongly correlated with the overexpression of Fms-like tyrosine kinase 3 (FLT3), a member of the class III receptor tyrosine kinase family. With the emergence of FLT3 internal tandem duplication alteration (ITD) and tyrosine kinase domain (TKD) mutations, the development of FLT3 small molecule inhibitors has become an effective medicinal chemistry strategy for AML. Herein, we have designed and synthesized two series of 1H-pyrrolo[2,3-b]pyridine derivatives CM1-CM24, as FLT3 inhibitors based on F14, which we previously reported, that can target the hydrophobic FLT3 back pocket. Among these derivates, CM5 showed significant inhibition of FLT3 and FLT3-ITD, with inhibitory percentages of 57.72 % and 53.77 % respectively at the concentration of 1 µΜ. Furthermore, CM5 demonstrated potent inhibition against FLT3-dependent human AML cell lines MOLM-13 and MV4-11 (both harboring FLT3-ITD mutant), with IC50 values of 0.75 µM and 0.64 µM respectively. In our cellular mechanistic studies, CM5 also effectively induces apoptosis by arresting cell cycle progression in the G0/G1 phase. In addition, the amide and urea linker function were discussed in detail based on computational simulations studies. CM5 will serve as a novel lead compound for further structural modification and development of FLT3 inhibitors specifically targeting AML with FLT3-ITD mutations.


Assuntos
Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Apoptose , Linhagem Celular Tumoral , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Piridinas/farmacologia
12.
Cell Mol Life Sci ; 81(1): 35, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214784

RESUMO

Diabetes mellitus is on the rise globally and is a known susceptibility factor for severe influenza virus infections. However, the mechanisms by which diabetes increases the severity of an influenza virus infection are yet to be fully defined. Diabetes mellitus is hallmarked by high glucose concentrations in the blood. We hypothesized that these high glucose concentrations affect the functionality of CD8+ T cells, which play a key role eliminating virus-infected cells and have been shown to decrease influenza disease severity. To study the effect of hyperglycemia on CD8+ T cell function, we stimulated peripheral blood mononuclear cells (PBMCs) from donors with and without diabetes with influenza A virus, anti-CD3/anti-CD28-coated beads, PMA and ionomycin (PMA/I), or an influenza viral peptide pool. After stimulation, cells were assessed for functionality [as defined by expression of IFN-γ, TNF-α, macrophage inflammatory protein (MIP)-1ß, and lysosomal-associated membrane protein-1 (CD107a)] using flow cytometry. Our results showed that increasing HbA1c correlated with a reduction in TNF-α production by CD8+ T cells in response to influenza stimulation in a TCR-specific manner. This was not associated with any changes to CD8+ T cell subsets. We conclude that hyperglycemia impairs CD8+ T cell function to influenza virus infection, which may be linked with the increased risk of severe influenza in patients with diabetes.


Assuntos
Diabetes Mellitus , Hiperglicemia , Vírus da Influenza A , Influenza Humana , Humanos , Linfócitos T CD8-Positivos/metabolismo , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Hemoglobinas Glicadas , Hiperglicemia/metabolismo , Leucócitos Mononucleares/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Biomed Pharmacother ; 169: 115905, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38000356

RESUMO

The therapeutic benefits of available FLT3 inhibitors for AML are limited by drug resistance, which is related to mutations, as well toxicity caused by off-target effects. In this study, we introduce a new small molecule FLT3 inhibitor called danatinib, which was designed to overcome the limitations of currently approved agents. Danatinib demonstrated greater potency and selectivity, resulting in cytotoxic activity specific to FLT3-ITD and/or FLT3-TKD mutated models. It also showed a superior kinome inhibition profile compared to several currently approved FLT3 inhibitors. In diverse FLT3-TKD models, danatinib exhibited substantially improved activity at clinically relevant doses, outperforming approved FLT3 inhibitors. In vivo safety evaluations performed on the granulopoiesis of transgenic myeloperoxidase (MPO) zebrafish and mice models proved danatinib to have an acceptable safety profile. Danatinib holds promise as a new and improved FLT3 inhibitor for the treatment of AML, offering long-lasting remissions and improved overall survival rates.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Animais , Camundongos , Peixe-Zebra , Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Mutação
14.
Lasers Med Sci ; 38(1): 279, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030741

RESUMO

The study aimed to investigate the clinical effect of transurethral columnar balloon dilation of the prostate combined with holmium laser in the treatment of bladder neck contracture (BNC). This retrospective study included 41 patients with BNC, who had been treated with transurethral columnar balloon dilation and holmium laser in our hospital from June 2020 to June 2022. Admission, operation, and discharge of all the patients were completed in 24 h. The patients' satisfaction, postoperative complications, and chronic pain after operation were followed up. Clinical parameters, such as International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), quality of life (QoL), and post-void residual volume (PVR) in pre-operation, 1 month and 6 months after operation were recorded. All patients underwent the operations successfully. Six patients experienced urge incontinence and one patient experienced recurrence of BNC after 12 months. At 1 month and 6 months after the operation, IPSS, QoL, PVR, and Qmax of the patients were significantly better than those before the operation (P < 0.05). Transurethral columnar balloon dilation of the prostate combined with holmium laser can effectively treat BNC with simple performance and satisfactory clinical effects. It is a minimally invasive treatment that can be conducted by simple day surgery.


Assuntos
Contratura , Terapia a Laser , Lasers de Estado Sólido , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Masculino , Humanos , Próstata/cirurgia , Bexiga Urinária/cirurgia , Lasers de Estado Sólido/uso terapêutico , Qualidade de Vida , Procedimentos Cirúrgicos Ambulatórios , Estudos Retrospectivos , Dilatação , Hiperplasia Prostática/cirurgia , Hiperplasia Prostática/complicações , Contratura/cirurgia , Contratura/complicações , Resultado do Tratamento
15.
Nano Lett ; 23(20): 9468-9473, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830499

RESUMO

Crystalline Bi4O4SeCl2 exhibits record-low 0.1 W/mK lattice thermal conductivity (κL), but the underlying transport mechanism is not yet understood. Using a theoretical framework which incorporates first-principles anharmonic lattice dynamics into a unified heat transport theory, we compute both the particle-like and glass-like components of κL in crystalline and pellet Bi4O4SeCl2 forms. The model includes intrinsic three- and four-phonon scattering processes and extrinsic defect and extended defect scattering contributing to the phonon lifetime, as well as temperature-dependent interatomic force constants linked to phonon frequency shifts and anharmonicity. Bi4O4SeCl2 displays strongly anisotropic complex crystal behavior with dominant glass-like transport along the cross-plane direction. The uncovered origin of κL underscores an intrinsic approach for designing extremely low κL materials.

16.
J Phys Chem Lett ; 14(36): 8139-8144, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37669454

RESUMO

Using ab initio lattice dynamics and a unified heat transport theory, we compute the lattice thermal conductivity (κL) of Li5Sn, a newly synthesized crystalline material for Li-ion batteries. The weak bonding in the Li-rich environment leads to significant softening of the optical phonon modes, temperature-induced hardening, and strong anharmonicity. This complexity is captured in the particle-like and glass-like components of κL by accounting for the temperature-dependent interatomic force constants acting on the renormalized phonon frequencies and three- and four-phonon scatterings contributing to the phonon lifetime. We predict very low room-temperature κL values of 0.857, 0.599, and 0.961 W/mK for the experimental Cmcm phase and 0.996, 0.908, and 1.385 W/mK for the theoretically predicted Immm phase along the main crystallographic directions. Both phases display complex crystal behavior with glass-like transport exceeding 20% above room-temperature and an unusual κL temperature dependence. Our results can be used to inform system-level thermal models of Li-ion batteries.

17.
Int J Biol Macromol ; 253(Pt 3): 126638, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37673163

RESUMO

In the present study, high purity gliadin was extracted from gluten by the marginally modified Osborne method and the effect of different pHs in the aqueous ethanol on the physicochemical properties of unloaded gliadin nanoparticles (UGNs) and lutein-loaded gliadin nanoparticles (LGNs) was investigated. The results revealed that the formation of UGNs and LGNs at diverse pHs was driven by a conjunction of hydrogen bonding, electrostatic interactions and hydrophobic effects, but their dominant roles varied at different pHs. pH also significantly impacted the surface hydrophobicity, secondary structure and aromatic amino acid microenvironment of UGNs and LGNs. LGNs at pH 5.0 and at pH 9.0 exhibited better loading capacity and could reach 9.7884 ± 0.0006 % and 9.7360 ± 0.0017 %, respectively. These two samples also had greater photostability and thermal stability. Half-lives of LGNs at pH 5.0 were 2.185 h and 54.579 h, respectively. Half-lives of LGNs at pH 9.0 were 2.937 h and 49.159 h, respectively. LGNs at pH 5.0 and LGNs at pH 9.0 also had higher bioaccessibility of lutein, with 15.98 ± 0.04 % and 15.27 ± 0.03 %, respectively. These findings yielded precious inspirations for designing innovative lutein delivery system.


Assuntos
Glutens , Nanopartículas , Glutens/química , Gliadina/química , Luteína/química , Estrutura Secundária de Proteína , Nanopartículas/química
18.
Int J Mol Sci ; 24(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629027

RESUMO

Impaired cholesterol synthesizing ability is considered a risk factor for the development of Alzheimer's disease (AD), as evidenced by reduced levels of key proteases in the brain that mediate cholesterol synthesis; however, cholesterol deposition has been found in neurons in tangles in the brains of AD patients. Although it has been shown that statins, which inhibit cholesterol synthesis, reduce the incidence of AD, this seems paradoxical for AD patients whose cholesterol synthesizing capacity is already impaired. In this study, we aimed to investigate the effects of aerobic exercise on cholesterol metabolism in the brains of APP/PS1 mice and to reveal the mechanisms by which aerobic exercise improves cognitive function in APP/PS1 mice. Our study demonstrates that the reduction of SEC24D protein, a component of coat protein complex II (COPII), is a key factor in the reduction of cholesterol synthesis in the brain of APP/PS1 mice. 12 weeks of aerobic exercise was able to promote the recovery of SEC24D protein levels in the brain through activation of protein kinase B (AKT), which in turn promoted the expression of mem-brane-bound sterol regulatory element-binding protein 2 (SREBP2) nuclear translocation and the expression of key proteases mediating cholesterol synthesis. Simultaneous aerobic exercise restored cholesterol transport capacity in the brain of APP/PS1 mice with the ability to efflux excess cholesterol from neurons and reduced neuronal lipid rafts, thereby reducing cleavage of the APP amyloid pathway. Our study emphasizes the potential of restoring intracerebral cholesterol homeostasis as a therapeutic strategy to alleviate cognitive impairment in AD patients.


Assuntos
Doença de Alzheimer , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Metabolismo dos Lipídeos , Cognição , Encéfalo , Doença de Alzheimer/terapia , Endopeptidases , Homeostase , Proteínas de Transporte Vesicular
19.
Environ Pollut ; 336: 122380, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37625774

RESUMO

Type 2 diabetes mellitus (DM) is a common chronic condition characterized by persistent hyperglycemia and is associated with insulin resistance (IR) in critical glucose-consuming tissues, including skeletal muscle and adipose tissue. Oxidative stress and mitochondrial dysfunction are known to play key roles in IR. Acrolein is a reactive aldehyde found in the diet and environment that is generated as a fatty acid product through the glucose autooxidation process under hyperglycemic conditions. Our previous studies have shown that acrolein impairs insulin sensitivity in normal and diabetic mice, and this effect can be reversed by scavenging acrolein. This study demonstrated that acrolein increased oxidative stress and inhibited mitochondrial respiration in differentiated C2C12 myotubes and differentiated 3T3-L1 adipocytes. As a result, insulin signaling pathways were inhibited, leading to reduced glucose uptake. Treatment with acrolein scavengers, N-acetylcysteine, or carnosine ameliorated mitochondrial dysfunction and inhibited insulin signaling. Additionally, an increase in acrolein expression correlated with mitochondrial dysfunction in the muscle and adipose tissues of diabetic mice. These findings suggest that acrolein-induced mitochondrial dysfunction contributes to IR, and scavenging acrolein is a potential therapeutic approach for treating IR.

20.
Sci Rep ; 13(1): 12424, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528172

RESUMO

GBM (Glioblastoma) is the most lethal CNS (Central nervous system) tumor in adults, which inevitably develops resistance to standard treatments leading to recurrence and mortality. TRIB1 is a serine/threonine pseudokinase which functions as a scaffold platform that initiates degradation of its substrates like C/EBPα through the ubiquitin proteasome system and also activates MEK and Akt signaling. We found that increased TRIB1 gene expression associated with worse overall survival of GBM patients across multiple cohorts. Importantly, overexpression of TRIB1 decreased RT/TMZ (radiation therapy/temozolomide)-induced apoptosis in patient derived GBM cell lines in vitro. TRIB1 directly bound to MEK and Akt and increased ERK and Akt phosphorylation/activation. We also found that TRIB1 protein expression was maximal during G2/M transition of cell cycle in GBM cells. Furthermore, TRIB1 bound directly to HDAC1 and p53. Importantly, mice bearing TRIB1 overexpressing tumors had worse overall survival. Collectively, these data suggest that TRIB1 induces resistance of GBM cells to RT/TMZ treatments by activating the cell proliferation and survival pathways thus providing an opportunity for developing new targeted therapeutics.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Temozolomida/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Apoptose/genética , Quinases de Proteína Quinase Ativadas por Mitógeno , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia
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