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1.
Cell ; 185(24): 4488-4506.e20, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36318922

RESUMO

When challenged by hypertonicity, dehydrated cells must recover their volume to survive. This process requires the phosphorylation-dependent regulation of SLC12 cation chloride transporters by WNK kinases, but how these kinases are activated by cell shrinkage remains unknown. Within seconds of cell exposure to hypertonicity, WNK1 concentrates into membraneless condensates, initiating a phosphorylation-dependent signal that drives net ion influx via the SLC12 cotransporters to restore cell volume. WNK1 condensate formation is driven by its intrinsically disordered C terminus, whose evolutionarily conserved signatures are necessary for efficient phase separation and volume recovery. This disorder-encoded phase behavior occurs within physiological constraints and is activated in vivo by molecular crowding rather than changes in cell size. This allows kinase activity despite an inhibitory ionic milieu and permits cell volume recovery through condensate-mediated signal amplification. Thus, WNK kinases are physiological crowding sensors that phase separate to coordinate a cell volume rescue response.


Assuntos
Proteínas Serina-Treonina Quinases , Fosforilação , Tamanho Celular
2.
FASEB J ; 38(3): e23437, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38305849

RESUMO

Impaired functionality and loss of islet ß-cells are the primary abnormalities underlying the pathogenesis of both type 1 and 2 diabetes (T1DM and T2DM). However, specific therapeutic and preventive mechanisms underlying these conditions remain unclear. Mitogen-activated protein kinase phosphatase-5 (MKP-5) has been implicated in carcinogenesis, lipid metabolism regulation, and immune cell activation. In a previous study, we demonstrated the involvement of exogenous MKP-5 in the regulation of obesity-induced T2DM. However, the role of endogenous MKP-5 in the T1DM and T2DM processes is unclear. Thus, mice with MKP-5 knockout (KO) were generated and used to establish mouse models of both T1DM and T2DM. Our results showed that MKP-5 KO exacerbated diabetes-related symptoms in mice with both T1DM and T2DM. Given that most phenotypic studies on islet dysfunction have focused on mice with T2DM rather than T1DM, we specifically aimed to investigate the role of endoplasmic reticulum stress (ERS) and autophagy in T2DM KO islets. To accomplish this, we performed RNA sequence analysis to gain comprehensive insight into the molecular mechanisms associated with ERS and autophagy in T2DM KO islets. The results showed that the islets from mice with MKP-5 KO triggered 5' adenosine monophosphate-activated protein kinase (AMPK)-mediated autophagy inhibition and glucose-regulated protein 78 (GRP-78)-dominated ERS. Hence, we concluded that the autophagy impairment, resulting in islet dysfunction in mice with MKP-5 KO, is mediated through GRP-78 involvement. These findings provide valuable insights into the molecular pathogenesis of diabetes and highlight the significant role of MKP-5. Moreover, this knowledge holds promise for novel therapeutic strategies targeting MKP-5 for diabetes management.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Ilhotas Pancreáticas , Camundongos , Animais , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Fosfatos/metabolismo , Ilhotas Pancreáticas/metabolismo
3.
J Neurosci ; 43(44): 7351-7360, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37684030

RESUMO

Bilateral common carotid artery (CCA) stenosis (BCAS) is a useful model to mimic vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning because of metal implantation. We have established a new low-cost VCID model that better mimics human VCID and is compatible with live-animal MRI. The right and the left CCAs were temporarily ligated to 32- and 34-gauge needles with three ligations, respectively. After needle removal, CCA blood flow, cerebral blood flow, white matter injury (WMI) and cognitive function were measured. In male mice, needle removal led to ∼49.8% and ∼28.2% blood flow recovery in the right and left CCA, respectively. This model caused persistent and long-term cerebral hypoperfusion in both hemispheres (more severe in the left hemisphere), and WMI and cognitive dysfunction in ∼90% of mice, which is more reliable compared with other models. Importantly, these pathologic changes and cognitive impairments lasted for up to 24 weeks after surgery. The survival rate over 24 weeks was 81.6%. Female mice showed similar cognitive dysfunction, but a higher survival rate (91.6%) and relatively milder white matter injury. A novel, low-cost VCID model compatible with live-animal MRI with long-term outcomes was established.SIGNIFICANCE STATEMENT Bilateral common carotid artery (CCA) stenosis (BCAS) is an animal model mimicking carotid artery stenosis to study vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning due to metal implantation. We established a new asymmetric BCAS model by ligating the CCA to various needle gauges followed by an immediate needle removal. Needle removal led to moderate stenosis in the right CCA and severe stenosis in the left CCA. This needle model replicates the hallmarks of VCID well in ∼90% of mice, which is more reliable compared with other models, has ultra-low cost, and is compatible with MRI scanning in live animals. It will provide a new valuable tool and offer new insights for VCID research.


Assuntos
Disfunção Cognitiva , Demência Vascular , Masculino , Camundongos , Feminino , Humanos , Animais , Constrição Patológica/complicações , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Demência Vascular/diagnóstico por imagem , Demência Vascular/etiologia , Demência Vascular/patologia , Cognição , Camundongos Endogâmicos C57BL
4.
J Neuroinflammation ; 21(1): 184, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075578

RESUMO

Traumatic brain injury (TBI) remains a leading cause of death and disability that places a great physical, social, and financial burden on individuals and the health system. In this review, we summarize new research into the metabolic changes described in clinical TBI trials, some of which have already shown promise for informing injury classification and staging. We focus our discussion on derangements in glucose metabolism, cell respiration/mitochondrial function and changes to ketone and lipid metabolism/oxidation to emphasize potentially novel biomarkers for clinical outcome prediction and intervention and offer new insights into possible underlying mechanisms from preclinical research of TBI pathology. Finally, we discuss nutrition supplementation studies that aim to harness the gut/microbiome-brain connection and manipulate systemic/cellular metabolism to improve post-TBI recovery. Taken together, this narrative review summarizes published TBI-associated changes in glucose and lipid metabolism, highlighting potential metabolite biomarkers for clinical use, the cellular processes linking these markers to TBI pathology as well as the limitations and future considerations for TBI "omics" work.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas Traumáticas/metabolismo , Humanos , Animais , Metabolismo dos Lipídeos/fisiologia , Glucose/metabolismo
5.
J Neuroinflammation ; 21(1): 69, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509618

RESUMO

Microglial Na/H exchanger-1 (NHE1) protein, encoded by Slc9a1, plays a role in white matter demyelination of ischemic stroke brains. To explore underlying mechanisms, we conducted single cell RNA-seq transcriptome analysis in conditional Slc9a1 knockout (cKO) and wild-type (WT) mouse white matter tissues at 3 days post-stroke. Compared to WT, Nhe1 cKO brains expanded a microglial subgroup with elevated transcription of white matter myelination genes including Spp1, Lgals3, Gpnmb, and Fabp5. This subgroup also exhibited more acidic pHi and significantly upregulated CREB signaling detected by ingenuity pathway analysis and flow cytometry. Moreover, the Nhe1 cKO white matter tissues showed enrichment of a corresponding oligodendrocyte subgroup, with pro-phagocytosis and lactate shuffling gene expression, where activated CREB signaling is a likely upstream regulator. These findings demonstrate that attenuation of NHE1-mediated H+ extrusion acidifies microglia/macrophage and may underlie the stimulation of CREB1 signaling, giving rise to restorative microglia-oligodendrocyte interactions for remyelination.


Assuntos
Encéfalo , Microglia , Trocador 1 de Sódio-Hidrogênio , Animais , Camundongos , Encéfalo/metabolismo , Receptor 1 de Quimiocina CX3C/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Oligodendroglia/metabolismo , Transdução de Sinais/genética , Trocador 1 de Sódio-Hidrogênio/metabolismo
6.
J Neuroinflammation ; 21(1): 220, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256783

RESUMO

BACKGROUND: The choroid plexus (ChP) helps maintain the homeostasis of the brain by forming the blood-CSF barrier via tight junctions (TJ) at the choroid plexus epithelial cells, and subsequently preventing neuroinflammation by restricting immune cells infiltration into the central nervous system. However, whether chronic cerebral hypoperfusion causes ChP structural damage and blood-CSF barrier impairment remains understudied. METHODS: The bilateral carotid stenosis (BCAS) model in adult male C57BL/6 J mice was used to induce cerebral hypoperfusion, a model for vascular contributions to cognitive impairment and dementia (VCID). BCAS-mediated changes of the blood-CSF barrier TJ proteins, apical secretory Na+-K+-Cl- cotransporter isoform 1 (NKCC1) protein and regulatory serine-threonine kinases SPAK, and brain infiltration of myeloid-derived immune cells were assessed. RESULTS: BCAS triggered dynamic changes of TJ proteins (claudin 1, claudin 5) accompanied with stimulation of SPAK-NKCC1 complex and NF-κB in the ChP epithelial cells. These changes impacted the integrity of the blood-CSF barrier, as evidenced by ChP infiltration of macrophages/microglia, neutrophils and T cells. Importantly, pharmacological blockade of SPAK with its potent inhibitor ZT1a in BCAS mice attenuated brain immune cell infiltration and improved cognitive neurological function. CONCLUSIONS: BCAS causes chronic ChP blood-CSF damage and immune cell infiltration. Our study sheds light on the SPAK-NKCC1 complex as a therapeutic target in neuroinflammation.


Assuntos
Estenose das Carótidas , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias , Animais , Camundongos , Masculino , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/etiologia , Estenose das Carótidas/patologia , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/metabolismo , Plexo Corióideo/patologia , Plexo Corióideo/metabolismo
7.
Small ; : e2404488, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39072900

RESUMO

A great challenge in the commercialization process of layered Ni-rich cathode material LiNixCoyMn1-x-yO2 (NCM, x ≥ 80%) for lithium-ion batteries is the surface instability, which is exacerbated by the increase in nickel content. The high surface alkalinity and unavoidable cathode/electrolyte interface side reactions result in significant decrease for the capacity of NCM material. Surface coating and doping are common and effective ways to improve the electrochemical performance of Ni-rich cathode material. In this study, an in situ reaction is induced on the surface of secondary particles of NCM material to construct a stable lithium sulfate coating, while achieving sulfur doping in the near surface region. The synergistic modification of lithium sulfate coating and lattice sulfur doping significantly reduced the content of harmful residual lithium compounds (RLCs) on the surface of NCM material, suppressed the side reactions between the cathode material surface and electrolyte and the degradation of surface structure of the NCM material, effectively improved the rate capability and cycling stability of the NCM material.

8.
J Transl Med ; 22(1): 220, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429732

RESUMO

BACKGROUND: Targeting CD47/SIRPα axis has emerged as a promising strategy in cancer immunotherapy. Despite the encouraging clinical efficacy observed in hematologic malignancies through CD47-SIRPα blockade, there are safety concerns related to the binding of anti-CD47 antibodies to CD47 on the membrane of peripheral blood cells. METHODS: In order to enhance the selectivity and therapeutic efficacy of the antibody, we developed a humanized anti-CD47 monoclonal antibody called Gentulizumab (GenSci059). The binding capacity of GenSci059 to CD47 was evaluated using flow cytometry and surface plasmon resonance (SPR) methods, the inhibitory effect of GenSci059 on the CD47-SIRPα interaction was evaluated through competitive ELISA assays. The anti-tumor activity of GenSci059 was assessed using in vitro macrophage models and in vivo patient-derived xenograft (PDX) models. To evaluate the safety profile of GenSci059, binding assays were conducted using blood cells. Additionally, we investigated the underlying mechanisms contributing to the weaker binding of GenSci059 to erythrocytes. Finally, toxicity studies were performed in non-human primates to assess the potential risks associated with GenSci059. RESULTS: GenSci059 displayed strong binding to CD47 in both human and monkey, and effectively inhibited the CD47-SIRPα interaction. With doses ranging from 5 to 20 mg/kg, GenSci059 demonstrated potent inhibition of the growth of subcutaneous tumor with the inhibition rates ranged from 30.3% to complete regression. Combination of GenSci059 with 2.5 mg/kg Rituximab at a dose of 2.5 mg/kg showed enhanced tumor inhibition compared to monotherapy, exhibiting synergistic effects. GenSci059 exhibited minimal binding to hRBCs compared to Hu5F9-G4. The binding of GenSci059 to CD47 depended on the cyclization of N-terminal pyroglutamic acid and the spatial conformation of CD47, but was not affected by its glycosylation modifications. A maximum tolerated dose (MTD) of 450 mg/kg was observed for GenSci059, and no significant adverse effects were observed in repeated dosages up to 10 + 300 mg/kg, indicating a favorable safety profile. CONCLUSION: GenSci059 selectively binds to CD47, effectively blocks the CD47/SIRPα axis signaling pathway and enhances the phagocytosis effects of macrophages toward tumor cells. This monoclonal antibody demonstrates potent antitumor activity and exhibits a favorable safety profile, positioning it as a promising and effective therapeutic option for cancer.


Assuntos
Antígeno CD47 , Neoplasias , Animais , Humanos , Neoplasias/patologia , Fagocitose , Macrófagos/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Imunoterapia/métodos , Modelos Animais de Doenças , Antígenos de Diferenciação/metabolismo , Antígenos de Diferenciação/farmacologia , Antígenos de Diferenciação/uso terapêutico
9.
Magn Reson Med ; 91(1): 357-367, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37798945

RESUMO

PURPOSE: pH enhanced (pHenh ) CEST imaging combines the pH sensitivity from amide and guanidino signals, but the saturation parameters have not been optimized. We propose pHdual as a variant of pHenh that suppresses background signal variations, while enhancing pH sensitivity and potential for imaging ischemic brain injury of stroke. METHODS: Simulation and in vivo rodent stroke experiments of pHenh MRI were performed with varied RF saturation powers for both amide and guanidino protons to optimize the contrast between lesion/normal tissues, while simultaneously minimizing signal variations across different types of normal tissues. In acute stroke, contrast and volume ratio measured by pHdual imaging were compared with an amide-CEST approach, and perfusion and diffusion MRI. RESULTS: Simulation experiments indicated that amide and guanidino CEST signals exhibit unique sensitivities across different pH ranges, with pHenh producing greater sensitivity over a broader pH regime. The pHenh data of rodent stroke brain demonstrated that the lesion/normal tissue contrast was maximized for an RF saturation power pair of 0.5 µT at 2.0 ppm and 1.0 µT at 3.6 ppm, whereas an optimal contrast-to-variation ratio (CVR) was obtained with a 0.7 µT saturation at 2.0 ppm and 0.8 µT at 3.6 ppm. In acute stroke, CVR optimized pHenh (i.e., pHdual ) achieved a higher sensitivity than the three-point amide-CEST approach, and distinct patterns of lesion tissue compared to diffusion and perfusion MRI. CONCLUSION: pHdual MRI improves the sensitivity of pH-weighted imaging and will be a valuable tool for assessing tissue viability in stroke.


Assuntos
Aumento da Imagem , Acidente Vascular Cerebral , Humanos , Concentração de Íons de Hidrogênio , Aumento da Imagem/métodos , Imagens de Fantasmas , Acidente Vascular Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Amidas
10.
Magn Reson Med ; 92(5): 2140-2148, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38923094

RESUMO

PURPOSE: Differentiating ischemic brain damage is critical for decision making in acute stroke treatment for better outcomes. We examined the sensitivity of amide proton transfer (APT) MRI, a pH-weighted imaging technique, to achieve this differentiation. METHODS: In a rat stroke model, the ischemic core, oligemia, and the infarct-growth region (IGR) were identified by tracking the progression of the lesions. APT MRI signals were measured alongside ADC, T1, and T2 maps to evaluate their sensitivity in distinguishing ischemic tissues. Additionally, stroke under hyperglycemic conditions was studied. RESULTS: The APT signal in the IGR decreased by about 10% shortly after stroke onset, and further decreased to 35% at 5 h, indicating a progression from mild to severe acidosis as the lesion evolved into infarction. Although ADC, T1, and T2 contrasts can only detect significant differences between the IGR and oligemia for a portion of the stroke duration, APT contrast consistently differentiates between them at all time points. However, the contrast to variation ratio at 1 h is only about 20% of the contrast to variation ratio between the core and normal tissues, indicating limited sensitivity. In the ischemic core, the APT signal decreases to about 45% and 33% of normal tissue level at 1 h for the normoglycemic and hyperglycemic groups, respectively, confirming more severe acidosis under hyperglycemia. CONCLUSION: The sensitivity of APT MRI is high in detecting severe acidosis of the ischemic core but is much lower in detecting mild acidosis, which may affect the accuracy of differentiation between the IGR and oligemia.


Assuntos
Acidose , Modelos Animais de Doenças , AVC Isquêmico , Imageamento por Ressonância Magnética , Prótons , Animais , Ratos , Acidose/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos Sprague-Dawley , Encéfalo/diagnóstico por imagem , Amidas , Isquemia Encefálica/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Sensibilidade e Especificidade
11.
Exp Eye Res ; 245: 109965, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38851477

RESUMO

Mitochondria-associated ER membranes (MAMs) are contact sites that enable bidirectional communication between the ER (endoplasmic reticulum) and mitochondria, including the transfer of Ca2+ signals. MAMs are essential for mitochondrial function and cellular energy metabolism. However, unrestrained Ca2+ transfer to the mitochondria can lead to mitochondria-dependent apoptosis. IP3R2 (Inositol 1,4,5-trisphosphate receptor 2) is an important intracellular Ca2+ channel. This study investigated the contribution of IP3R2-MAMs to hypoxia-induced apoptosis in photoreceptor cells. A photoreceptor hypoxia model was established by subretinal injection of hyaluronic acid (1%) in C57BL/6 mice and 1% O2 treatment in 661W cells. Transmission electron microscopy (TEM), ER-mitochondria colocalization, and the MAM reporter were utilized to evaluate MAM alterations. Cell apoptosis and mitochondrial homeostasis were evaluated using immunofluorescence (IF), flow cytometry, western blotting (WB), and ATP assays. SiRNA transfection was employed to silence IP3R2 in 661W cells. Upon hypoxia induction, MAMs were significantly increased in photoreceptors both in vivo and in vitro. This was accompanied by the activation of mitochondrial apoptosis and disruption of mitochondrial homeostasis. Elevated MAM-enriched IP3R2 protein levels induced by hypoxic injury led to mitochondrial calcium overload and subsequent photoreceptor apoptosis. Notably, IP3R2 knockdown not only improved mitochondrial morphology but also restored mitochondrial function in photoreceptors by limiting MAM formation and thereby attenuating mitochondrial calcium overload under hypoxia. Our results suggest that IP3R2-MAM-mediated mitochondrial calcium overload plays a critical role in mitochondrial dyshomeostasis, ultimately contributing to photoreceptor cell death. Targeting MAM constitutive proteins might provide an option for a therapeutic approach to mitigate photoreceptor death in retinal detachment.


Assuntos
Apoptose , Cálcio , Retículo Endoplasmático , Receptores de Inositol 1,4,5-Trifosfato , Mitocôndrias , Animais , Camundongos , Western Blotting , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Citometria de Fluxo , Hipóxia/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia
12.
Bioorg Med Chem Lett ; 110: 129863, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38942129

RESUMO

Glioblastoma (GBM) is the most common form of malignant primary brain tumor and is one of the most lethal cancers. The difficulty in treating GBM stems from its highly developed mechanisms of drug resistance. Our research team has recently identified the fungal secondary metabolite ophiobolin A (OpA) as an agent with significant activity against drug-resistant GBM cells. However, the OpA's mode of action is likely based on covalent modification of its intracellular target(s) and thus possible off-target reactivity needs to be addressed. This work involves the investigation of an acid-sensitive OpA analogue approach that exploits the elevated acidity of the GBM microenvironment to enhance the selectivity for tumor targeting. This project identified analogues that showed selectivity at killing GBM cells grown in cultures at reduced pH compared to those maintained under normal neutral conditions. These studies are expected to facilitate the development of OpA as an anti-GBM agent by investigating its potential use in an acid-sensitive analogue form with enhanced selectivity for tumor targeting.


Assuntos
Antineoplásicos , Sesterterpenos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Sesterterpenos/química , Sesterterpenos/farmacologia , Linhagem Celular Tumoral , Concentração de Íons de Hidrogênio , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-Atividade , Estrutura Molecular , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga
13.
Acta Pharmacol Sin ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103531

RESUMO

Liver fibrosis, one of the leading causes of morbidity and mortality worldwide, lacks effective therapy. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. Luteolin-7-diglucuronide (L7DG) is the major flavonoid extracted from Perilla frutescens and Verbena officinalis. Their beneficial effects in the treatment of liver diseases were well documented. In this study we investigated the anti-fibrotic activities of L7DG and the potential mechanisms. We established TGF-ß1-activated mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 as in vitro liver fibrosis models. Co-treatment with L7DG (5, 20, 50 µM) dose-dependently decreased TGF-ß1-induced expression of fibrotic markers collagen 1, α-SMA and fibronectin. In liver fibrosis mouse models induced by CCl4 challenge alone or in combination with HFHC diet, administration of L7DG (40, 150 mg·kg-1·d-1, i.g., for 4 or 8 weeks) dose-dependently attenuated hepatic histopathological injury and collagen accumulation, decreased expression of fibrogenic genes. By conducting target prediction, molecular docking and enzyme activity detection, we identified L7DG as a potent inhibitor of protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 2.10 µM. Further studies revealed that L7DG inhibited PTP1B activity, up-regulated AMPK phosphorylation and subsequently inhibited HSC activation. This study demonstrates that the phytochemical L7DG may be a potential therapeutic candidate for the treatment of liver fibrosis.

14.
Environ Res ; 257: 119403, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38871274

RESUMO

Commonly utilized as a plasticizer in the food and chemical sectors, Dibutyl phthalate (DBP) poses threats to the environment and human well-being as it seeps or moves into the surroundings. Nevertheless, research on the harmfulness of DBP to aquatic organisms is limited, and its impact on stem cells and tissue regeneration remains unidentified. Planarians, recognized for their robust regenerative capabilities and sensitivity to aquatic pollutants, are emerging animal models in toxicology. This study investigated the comprehensive toxicity effects of environmentally relevant levels of DBP on planarians. It revealed potential toxicity mechanisms through the use of immunofluorescence, chromatin dispersion assay, Western blot, quantitative real-time fluorescence quantitative PCR (qRT-PCR), chromatin behavioral and histological analyses, immunofluorescence, and terminal dUTP nickel-end labeling (TUNEL). Findings illustrated that DBP caused morphological and motor abnormalities, tissue damage, regenerative inhibition, and developmental neurotoxicity. Further research revealed increased apoptosis and suppressed stem cell proliferation and differentiation, disrupting a balance of cell proliferation and death, ultimately leading to morphological defects and functional abnormalities. This was attributed to oxidative stress and DNA damage caused by excessive release of reactive oxygen species (ROS). This exploration furnishes fresh perspectives on evaluating the toxicity peril posed by DBP in aquatic organisms.


Assuntos
Dibutilftalato , Planárias , Regeneração , Poluentes Químicos da Água , Animais , Dibutilftalato/toxicidade , Planárias/efeitos dos fármacos , Planárias/fisiologia , Poluentes Químicos da Água/toxicidade , Regeneração/efeitos dos fármacos , Ecotoxicologia , Estresse Oxidativo/efeitos dos fármacos , Plastificantes/toxicidade , Apoptose/efeitos dos fármacos
15.
Graefes Arch Clin Exp Ophthalmol ; 262(1): 81-91, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37367995

RESUMO

PURPOSES: This work aimed to assess the possible role of TRIM25 in regulating hyperglycemia-induced inflammation, senescence, and oxidative stress in retinal microvascular endothelial cells, all of which exert critical roles in the pathological process of diabetic retinopathy. METHODS: The effects of TRIM25 were investigated using streptozotocin-induced diabetic mice, human primary retinal microvascular endothelial cells cultured in high glucose, and adenoviruses for TRIM25 knockdown and overexpression. TRIM25 expression was evaluated by western blot and immunofluorescence staining. Inflammatory cytokines were detected by western blot and quantitative real-time PCR. Cellular senescence level was assessed by detecting senescent marker p21 and senescence-associated-ß-galactosidase activity. The oxidative stress state was accessed by detecting reactive oxygen species and mitochondrial superoxide dismutase. RESULTS: TRIM25 expression is elevated in the endothelial cells of the retinal fibrovascular membrane from diabetic patients compared with that of the macular epiretinal membrane from non-diabetic patients. Moreover, we have also observed a significant increase in TRIM25 expression in diabetic mouse retina and retinal microvascular endothelial cells under hyperglycemia. TRIM25 knockdown suppressed hyperglycemia-induced inflammation, senescence, and oxidative stress in human primary retinal microvascular endothelial cells while TRIM25 overexpression further aggregates those injuries. Further investigation revealed that TRIM25 promoted the inflammatory responses mediated by the TNF-α/NF-κB pathway and TRIM25 knockdown improved cellular senescence by increasing SIRT3. However, TRIM25 knockdown alleviated the oxidative stress independent of both SIRT3 and mitochondrial biogenesis. CONCLUSION: Our study proposed TRIM25 as a potential therapeutic target for the protection of microvascular function during the progression of diabetic retinopathy.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Hiperglicemia , Sirtuína 3 , Animais , Humanos , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Inflamação/metabolismo , Estresse Oxidativo , Retina/patologia , Sirtuína 3/metabolismo , Sirtuína 3/farmacologia , Fatores de Transcrição , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/farmacologia
16.
Luminescence ; 39(6): e4807, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890121

RESUMO

ZnAl2O4 with a typical spinel structure is highly expected to be a novel rare-earth-free ion-activated oxide phosphor with red emission, which holds high actual meaning for advancing phosphor-converted light-emitting diode (pc-LED) lighting. Among the rare-earth-free activators, Mn4+ ions have emerged as one of the most promising activators. Considering the price advantage of MnCO3 generating Mn2+ ions and the charge compensation effect potentially obtaining Mn4+ ions from Mn2+ ions, this research delves into a collection of ZnAl2O4:Mn2+(Mn4+), x Li+ (x = 0%-40%) phosphors with Li+ as co-dopant and MnCO3 as Mn2+ dopant source prepared by a high temperature solid-state reaction method. The lattice structure was investigated using X-ray diffraction (XRD), photoluminescence (PL), and photoluminescence excitation (PLE) spectroscopy. Results suggest a relatively high probability of Li+ ions occupying Zn2+ lattice sites. Furthermore, Li+ ion doping was assuredly found to facilitate the oxidization of Mn2+ to Mn4+, leading to a shift of luminescence peak from 516 to 656 nm. An intriguing phenomenon that the emission color changed with the Li+ doping content was also observed. Meanwhile, the luminescence intensity and quantum yield (QY) at different temperatures, as well as the relevant thermal quenching mechanism, were determined and elucidated detailedly.


Assuntos
Alumínio , Lítio , Luminescência , Manganês , Fósforo , Zinco , Alumínio/química , Zinco/química , Manganês/química , Lítio/química , Fósforo/química , Cátions
17.
Neurobiol Dis ; 179: 106063, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36889482

RESUMO

Recent research highlights the function of regulatory T cells (Tregs) in white matter integrity in CNS diseases. Approaches that expand the number of Tregs have been utilized to improve stroke recovery. However, it remains unclear if Treg augmentation preserves white matter integrity early after stroke or promotes white matter repair. This study evaluates the effect of Treg augmentation on white matter injury and repair after stroke. Adult male C57/BL6 mice randomly received Treg or splenocyte (2 million, iv) transfer 2 h after transient (60 min) middle cerebral artery occlusion (tMCAO). Immunostaining showed improved white matter recovery after tMCAO in Treg-treated mice compared to mice received splenocytes. In another group of mice, IL-2/IL-2 antibody complexes (IL-2/IL-2Ab) or isotype IgG were administered (i.p) for 3 consecutive days starting 6 h after tMCAO, and repeated on day 10, 20 and 30. The IL-2/IL-2Ab treatment boosted the number of Tregs in blood and spleen and increased Treg infiltration into the ischemic brain. Longitudinal in vivo and ex vivo diffusion tensor imaging analysis revealed an increase in fractional anisotropy 28d and 35d, but not 14d, after stroke in IL-2/IL-2Ab-treated mice compared to isotype-treated mice, suggesting a delayed improvement in white matter integrity. IL-2/IL-2Ab also improved sensorimotor functions (rotarod test and adhesive removal test) 35d after stroke. There were correlations between white matter integrity and behavior performance. Immunostaining confirmed the beneficial effects of IL-2/IL-2Ab on white matter structures 35d after tMCAO. IL-2/IL-2Ab treatment starting as late as 5d after stroke still improved white matter integrity 21d after tMCAO, suggesting long-term salutary effects of Tregs on the late-stage tissue repair. We also found that IL-2/IL-2Ab treatment reduced the number of dead/dying OPCs and oligodendrocytes in the brain 3d after tMCAO. To confirm the direct effect of Tregs on remyelination, Tregs were cocultured with lysophosphatidyl choline (LPC)-treated organotypic cerebella. LPC exposure for 17 h induced demyelination in organotypic cultures, followed by gradual spontaneous remyelination upon removal of LPC. Co-culture with Tregs accelerated remyelination in organotypic cultures 7d after LPC. In conclusion, Boosting the number of Tregs protects oligodendrocyte lineage cells early after stroke and promotes long-term white matter repair and functional recovery. IL-2/IL-2Ab represents a feasible approach of Treg expansion for stroke treatment.


Assuntos
Acidente Vascular Cerebral , Substância Branca , Camundongos , Masculino , Animais , Linfócitos T Reguladores , Imagem de Tensor de Difusão , Interleucina-2/farmacologia , Camundongos Endogâmicos C57BL
18.
Bioinformatics ; 38(22): 5137-5138, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36130260

RESUMO

SUMMARY: Advances in metabolic engineering have boosted the production of bulk chemicals, resulting in tons of production volumes of some bulk chemicals with very low prices. A decrease in the production cost and overproduction of bulk chemicals makes it necessary and desirable to explore the potential to synthesize higher-value products from them. It is also useful and important for society to explore the use of design methods involving synthetic biology to increase the economic value of these bulk chemicals. Therefore, we developed 'BioBulkFoundary', which provides an elaborate analysis of the biosynthetic potential of bulk chemicals based on the state-of-art exploration of pathways to synthesize value-added chemicals, along with associated comprehensive technology and economic database into a user-friendly framework. AVAILABILITY AND IMPLEMENTATION: Freely available on the web at http://design.rxnfinder.org/biobulkfoundary/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Engenharia Metabólica , Biologia Sintética , Engenharia Metabólica/métodos , Bases de Dados Factuais
19.
Anal Biochem ; 670: 115136, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37028780

RESUMO

Liquid chromatography coupled to mass spectrometry (LC-MS) is widely used for host cell proteins (HCP) identification in antibody drug development because of its sensitivity, selectivity, and adaptability. However, LC-MS based identification of HCP in biotherapeutics produced from the prokaryotic Escherichia coli-derived growth hormone (GH) has rarely been reported. Herein, we developed a universal and powerful workflow by combining optimized sample preparation with one-dimension ultra-high performance LC-MS based shotgun proteomics to support HCP profiling in GH samples from downstream pools and the final product, which would be beneficial to direct the purification process development and compare the difference of impurity of different products for guiding the development of the biosimilar. A standard-spiking strategy was also developed to increase the depth of HCP identification. Spiking with standards enables additional identification of HCP species, which is promising for trace-level HCP analysis. Our universal and standard-spiking protocols would open an avenue for profiling HCP in biotherapeutics derived from prokaryotic host cells.


Assuntos
Anticorpos Monoclonais , Escherichia coli , Animais , Cricetinae , Anticorpos Monoclonais/química , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas/métodos , Escherichia coli/metabolismo , Hormônio do Crescimento , Cricetulus , Células CHO
20.
Psychol Med ; 53(8): 3557-3567, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35536000

RESUMO

BACKGROUND: The association between executive dysfunction, brain dysconnectivity, and inflammation is a prominent feature across major psychiatric disorders (MPDs), schizophrenia, bipolar disorder, and major depressive disorder. A dimensional approach is warranted to delineate their mechanistic interplay across MPDs. METHODS: This single site study included a total of 1543 participants (1058 patients and 485 controls). In total, 1169 participants underwent diffusion tensor and resting-state functional magnetic resonance imaging (745 patients and 379 controls completed the Wisconsin Card Sorting Test). Fractional anisotropy (FA) and regional homogeneity (ReHo) assessed structural and functional connectivity, respectively. Pro-inflammatory cytokine levels [interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α] were obtained in 325 participants using blood samples collected with 24 h of scanning. Group differences were determined for main measures, and correlation and mediation analyses and machine learning prediction modeling were performed. RESULTS: Executive deficits were associated with decreased FA, increased ReHo, and elevated IL-1ß and IL-6 levels across MPDs, compared to controls. FA and ReHo alterations in fronto-limbic-striatal regions contributed to executive deficits. IL-1ß mediated the association between FA and cognition, and IL-6 mediated the relationship between ReHo and cognition. Executive cognition was better predicted by both brain connectivity and cytokine measures than either one alone for FA-IL-1ß and ReHo-IL-6. CONCLUSIONS: Transdiagnostic associations among brain connectivity, inflammation, and executive cognition exist across MPDs, implicating common neurobiological substrates and mechanisms for executive deficits in MPDs. Further, inflammation-related brain dysconnectivity within fronto-limbic-striatal regions may represent a transdiagnostic dimension underlying executive dysfunction that could be leveraged to advance treatment.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Interleucina-6 , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Cognição , Biomarcadores , Inflamação/diagnóstico por imagem
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