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1.
Biochem Biophys Res Commun ; 630: 133-142, 2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36155059

RESUMO

The phenotypic transformation of vascular smooth muscle cells (VSMCs) plays a key role in the pathological process of atherosclerosis (AS), and TRPM7 is involved in this process. In this study, we verified whether circRNAs participate in the phenotypic transformation of VSMCs by regulating TRPM7 in AS. The RNA-sequencing data of atherosclerosis were downloaded and analysed from the GEO database. Only hsa_circ_0021155 related to TRPM7 was differentially expressed in AS. circRNA distribution and expression were observed via FISH and PCR. CCK8, scratch test and Transwell assay were used to observe the proliferation and migration of cells. Western blot was performed to examine changes in α-actin, calponin, SMMHC and TRPM7 proteins. The expression of hsa_circ_0021155 against has-miR-4459/miR-3689c was verified via PCR. The ceRNA relationship of TPRM7-miR4459-circ0021155 was verified via dual luciferase assay, and the effects of miR4459 mimic/inhibitor on the proliferation of cells were further observed. The expression of hsa_circ_0021155 and OX-LDL was increased in VSMCs. hsa_circ_0021155 promoted the expression of TRPM7 and inhibited the protein expression of α-actin, calponin and SMMHC. In addition, it promoted the proliferation and migration of cells and inhibited the expression of miR-3689c and miR-4459 but did not affect miR-4756-5p. The dual luciferase assay showed that circ0021155-miR4459-TRPM7 mRNA was highly compatible and could be mutually regulated by a ceRNA network. In conclusion, hsa_circ_0021155 regulates the proliferation, migration and phenotype transformation of VSMCs induced by OX-LDL via the miR-4459/TRPM7 axis. hsa_circ_0021155 and TRPM7 may offer novel therapeutic targets for atherosclerosis.


Assuntos
Aterosclerose , MicroRNAs , Canais de Cátion TRPM , Actinas/metabolismo , Apoptose/genética , Aterosclerose/genética , Aterosclerose/patologia , Movimento Celular/genética , Proliferação de Células/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases , RNA Circular/genética , RNA Mensageiro , Canais de Cátion TRPM/genética
2.
Cell Biochem Funct ; 39(7): 908-920, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34296452

RESUMO

Increasing attention has been paid on the application of biodegradable materials such as magnesium and its alloys in neuron repair. AZ91D magnesium alloy coated with carbon nanotubes (CNTs) and/or calcium phosphate (CaP)/chitosan (CS) was fabricated in this study. To evaluate the bioactivity of these AZ91D-based composites, the extracts were prepared by immersing samples in modified simulated body fluid (m-SBF) for 0, 2, 8, 16, 24, 34, 44, 60, or 90 days. Immunofluorescence staining for neuronal class III ß-tubulin (TUJ1) revealed that both CNTs-CaP/CS-AZ91D and CaP/CS-AZ91D extracts promoted axon outgrowth of dorsal root ganglia (DRG) neurons, accompanied with increased expression of phosphorylated focal adhesion kinase (p-FAK) and growth associated protein-43 (GAP-43). Besides, the extracts increased the expression and the release of neurotrophic factors including nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). ERK signalling was activated in DRG neurons after treating with either CNTs-CaP/CS-AZ91D or CaP/CS-AZ91D extracts, and its inhibition with U0126 counteracted the beneficial effects of these extracts on DRG neuron. Overall, the extracts from these AZ91D-based composites might promote DRG neuron growth via activating ERK signalling pathway. Notably, CNTs-CaP/CS-AZ91D extracts showed a better promoting effect on neuron growth than CaP/CS-AZ91D. Assessment of ion elements showed that the addition of CNTs coating enhanced magnesium corrosion resistance and reduced the deposition of calcium and phosphorus on the surface of CaP/CS-AZ91D alloy. These findings demonstrate that CNTs-CaP/CS-AZ91D likely provide a more suitable environment for neuron growth, which suggests a potential implantable biomaterial for the treatment of nerve injury. SIGNIFICANCE: AZ91D magnesium alloy coated with carbon nanotubes (CNTs) and/or calcium phosphate (CaP)/chitosan (CS) was fabricated and their immersion extracts were prepared using modified simulated body fluid in this study. Both extracts from CNTs-CaP/CS and CaP/CS-coated AZ91D magnesium alloy promotes rat dorsal root ganglia (DRG) neuron growth via activating ERK signalling pathway. Notably, the addition of CNTs improves the performance of CaP/CS-AZ91D. For the first time, our research demonstrates that CNTs-CaP/CS-AZ91D likely provide a suitable environment for neuron growth, suggesting these AZ91D-based composites as potential implantable biomaterials for the treatment of nerve injury.


Assuntos
Ligas/farmacologia , Fosfatos de Cálcio/farmacologia , Quitosana/farmacologia , Magnésio/farmacologia , Nanotubos de Carbono/química , Ligas/química , Ligas/isolamento & purificação , Animais , Fosfatos de Cálcio/química , Fosfatos de Cálcio/isolamento & purificação , Quitosana/química , Quitosana/isolamento & purificação , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/crescimento & desenvolvimento , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Magnésio/química , Magnésio/isolamento & purificação , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
3.
Hum Mol Genet ; 27(4): 625-637, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29294000

RESUMO

Paroxysmal kinesigenic dyskinesia (PKD) is a heterogeneous movement disorder characterized by recurrent dyskinesia attacks triggered by sudden movement. PRRT2 has been identified as the first causative gene of PKD. However, it is only responsible for approximately half of affected individuals, indicating that other loci are most likely involved in the etiology of this disorder. To explore the underlying causative gene of PRRT2-negative PKD, we used a combination strategy including linkage analysis, whole-exome sequencing and copy number variations analysis to detect the genetic variants within a family with PKD. We identified a linkage locus on chromosome 12 (12p13.32-12p12.3) and detected a novel heterozygous mutation c.956 T>G (p.319 L>R) in the potassium voltage-gated channel subfamily A member 1, KCNA1. Whole-exome sequencing in another 58 Chinese patients with PKD who lacked mutations in PRRT2 revealed another novel mutation in the KCNA1 gene [c.765 C>A (p.255 N>K)] within another family. Biochemical analysis revealed that the L319R mutant accelerated protein degradation via the proteasome pathway and disrupted membrane expression of the Kv1.1 channel. Electrophysiological examinations in transfected HEK293 cells showed that both the L319R and N255K mutants resulted in reduced potassium currents and respective altered gating properties, with a dominant negative effect on the Kv1.1 wild-type channel. Our study suggests that these mutations in KCNA1 cause the Kv1.1 channel dysfunction, which leads to familial PKD. The current study further extended the genotypic spectrum of this disorder, indicating that Kv1.1 channel dysfunction maybe one of the underlying defects in PKD.


Assuntos
Distonia/genética , Canal de Potássio Kv1.1/genética , Adulto , Povo Asiático , Variações do Número de Cópias de DNA , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Linhagem
4.
Cell Physiol Biochem ; 40(6): 1274-1288, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27997885

RESUMO

BACKGROUND: Streptozotocin (STZ) has served as an agent to generate an Alzheimer's disease (AD) model in rats, while edaravone (EDA), a novel free radical scavenger, has recently emerged as an effective treatment for use in vivo and vitro AD models. However, to date, these beneficial effects of EDA have only been clearly demonstrated within STZ-induced animal models of AD and in cell models of AD. A better understanding of the mechanisms of EDA may provide the opportunity for their clinical application in the treatment of AD. Therefore, the purpose of this study was to investigate the underlying mechanisms of STZ and EDA as assessed upon electrophysiological alterations in CA1 pyramidal neurons of rat hippocampal slices. METHODS: Through measures of evoked excitatory postsynaptic currents (eEPSCs), AMPAR-mediated eEPSCs (eEPSCsAMPA), evoked inhibitory postsynaptic currents (eIPSCs), evoked excitatory postsynaptic current paired pulse ratio (eEPSC PPR) and evoked inhibitory postsynaptic current paired pulse ratio (eIPSC PPR), it was possible to investigate mechanisms as related to the neurotoxicity of STZ and reductions in these effects by EDA. RESULTS: Our results showed that STZ (1000 µM) significantly inhibited peak amplitudes of eEPSCs, eEPSCsAMPA and eIPSCs, while EDA (1000 µM) attenuated these STZ-induced changes at holding potentials ranging from -60mV to +40 mV for EPSCs and -60mV to +20 mV for IPSCs. Our work also indicated that mean eEPSC PPR were substantially altered by STZ, effects which were partially restored by EDA. In contrast, no significant effects upon eIPSC PPR were obtained in response to STZ and EDA. CONCLUSION: Our data suggest that STZ inhibits glutamatergic transmission involving pre-synaptic mechanisms and AMPAR, and that STZ inhibits GABAergic transmission by post-synaptic mechanisms within CA1 pyramidal neurons. These effects are attenuated by EDA.


Assuntos
Antipirina/análogos & derivados , Região CA1 Hipocampal/citologia , Células Piramidais/fisiologia , Estreptozocina/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Animais , Antipirina/farmacologia , Edaravone , Capacitância Elétrica , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Masculino , Potenciais da Membrana/efeitos dos fármacos , Células Piramidais/efeitos dos fármacos , Ratos Wistar , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
6.
Biochem Biophys Res Commun ; 463(4): 1297-304, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26093297

RESUMO

PURPOSE: Genistein, as a protein tyrosine kinase inhibitor, has been shown to possess anti-atherosclerotic effects. Since the smooth muscle cell-derived foam cells are key components of atherosclerotic plaques. The aim of this study is to investigate the influence of genistein on foam cell transformation from vascular smooth muscle cells and possible mechanisms contributing to these effects. METHODS AND RESULTS: Vascular smooth muscle cells exposed to ox-LDL developed into foam cell, as demonstrated by Oil Red O staining and cholesterol content analysis. Ox-LDL induced phenotype transformation of smooth muscle cells, decreased expression of α-actin and increased expression of CD68 (a specific marker for monocytes, can also function as a subtype of scavenger receptors). The expression of scavenger receptors CD36 and LOX-1 was measured, and their role in foam cell formation in the presence of genistein, daidzein (a structurally similar analogue of genistein) and herbimycin A (a commonly tyrosine kinase inhibitor). The results showed that foam cell formation was markedly reduced by genistein and herbimycin A, as well as the expression of CD68, CD36 and LOX-1. However, daidzein had no such effect. In addition, genistein-induced down-regulation of CD68, CD36 and LOX-1 could be reversed by sodium orthovanadate (a membrane-permeable protein tyrosine phosphatase inhibitor). CONCLUSION: The results showed that ox-LDL induce smooth muscle cell-derived foam cell formation and transform the phenotype of smooth muscle cell. While tyrosine kinase inhibitor, genistein could suppress smooth muscle cell-derived foam cell formation through inhibiting the protein expressions of CD68, CD36 and LOX-1.


Assuntos
Genisteína/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/metabolismo , Animais , Células Cultivadas , Isoflavonas/farmacologia , Lipoproteínas LDL/farmacologia , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/enzimologia , Ratos , Ratos Wistar , Rifabutina/análogos & derivados , Rifabutina/farmacologia
7.
Mol Cell Biochem ; 406(1-2): 139-49, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25987498

RESUMO

Arterial calcification is common in vascular diseases and involves conversion of vascular smooth muscle cells (VSMCs) to an osteoblast phenotype. Clinical studies suggest that the development of atherosclerosis can be promoted by homocysteine (HCY), but the mechanisms remain unclear. Here, we determined whether increases in HCY levels lead to an increase in VSMC calcification and differentiation, and examined the role of an extracellular matrix remodeler, matrix metalloproteinase-2 (MMP-2). Rat VSMCs were exposed to calcification medium in the absence or presence of HCY (10, 100 or 200 µmol/L) or an MMP-2 inhibitor (10(-6) or 10(-5) mol/L). MTT assays were performed to determine the cytotoxicity of the MMP-2 inhibitor in calcification medium containing 200 µmol/L HCY. Calcification was assessed by measurements of calcium deposition and alkaline phosphatase (ALP) activity as well as von Kossa staining. Expression of osteocalcin, bone morphogenetic protein (BMP)-2, and osteopontin, and MMP-2 was determined by immunoblotting. Calcification medium induced osteogenic differentiation of VSMCs. HCY promoted calcification, increased osteocalcin and BMP-2 expression, and decreased expression of osteopontin. MMP-2 expression was increased by HCY in a dose-dependent manner in VSMCs exposed to both control and calcification medium. The MMP-2 inhibitor decreased the calcium content and ALP activity, and attenuated the osteoblastic phenotype of VSMCs. Vascular calcification and osteogenic differentiation of VSMCs were positively regulated by HCY through increased/restored MMP-2 expression, increased expression of calcification proteins, and decreased anti-calcification protein levels. In summary, MMP-2 inhibition may be a protective strategy against VSMC calcification.


Assuntos
Diferenciação Celular , Homocisteína/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/patologia , Calcificação Vascular/enzimologia , Animais , Fosfatos de Cálcio/metabolismo , Células Cultivadas , Indução Enzimática , Masculino , Metaloproteinase 2 da Matriz/genética , Músculo Liso Vascular/metabolismo , Osteogênese , Fenótipo , Ratos , Ratos Wistar
8.
J Cardiovasc Pharmacol ; 66(1): 16-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26164719

RESUMO

Transient receptor potential melastatin 7 (TRPM7) is a Ca, Mg permeable nonselective cation channel of the TRP channel superfamily and plays an important role in cell growth and proliferation. Compounds that alter the activity and expression of the channel protein might be of therapeutic interest. In this study, we investigated the effects of genistein on TRPM7 channels and the proliferation of rat aortic smooth muscle cells (RAoSMCs). In primary cultured RAoSMCs, acute genistein (50 µM) exposure inhibited native TRPM7 currents, whereas chronic expose to genistein (50 µM) downregulated TRPM7 protein expression. The downregulation of TRPM7 protein expression induced by genistein was mimicked by c-Src inhibitor (PP2), but not by epidermal growth factor receptor tyrosine kinase inhibitor (lavendustin A), or daidzein. Additionally, genistein (50 µM) attenuated angiotensin II-induced cell proliferation. This study is the first to demonstrate inhibition of TRPM7 by isoflavone genistein through c-Src tyrosine kinase inhibition in RAoSMCs. Our results not only provide a new modulation mechanism of TRPM7 but also suggest that TRPM7 may serve as a new therapeutic target of genistein in the treatment of vascular diseases.


Assuntos
Angiotensina II/toxicidade , Aorta/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Genisteína/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Canais de Cátion TRPM/antagonistas & inibidores , Animais , Aorta/metabolismo , Proliferação de Células/fisiologia , Células Cultivadas , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Wistar , Canais de Cátion TRPM/metabolismo
9.
Phytomedicine ; 129: 155575, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38636179

RESUMO

BACKGROUND: The prevalence and incidence of type 2 diabetes mellitus (T2DM) have dramatically increased. The intestinal flora and its derived metabolites are demonstrated to play vital roles in the etiology and onset of T2DM. Shouhuitongbian (SHTB) is a traditional Chinese formula to treat constipation. SHTB is composed of seven herbs and components of Colla corii asini (CCA) that are obtained from the hide of Equus asinus L.. Some of herbs in SHTB such as Aloe vera (L.) Burm.f., Cassia obtusifolia L., fruits of Lycium barbarum L., and Citrus aurantium L. have shown to improve insulin resistance (IR) and T2DM in early reports. We hypothesized that SHTB composed of these herbs has antidiabetic effects. The antidiabetic efficacy and mechanism of action of SHTB have not been previously reported. HYPOTHESIS/PURPOSE: To demonstrate the antidiabetic effect and elucidate the underlying mechanisms of SHTB from the perspective of gut microbiota. STUDY DESIGN: The main compounds were identified and quantified by high-performance liquid chromatography (HPLC)-mass spectrometry analysis. High fat diet (HFD)-fed mice and db/db mice were used to assess the antidiabetic effects and the mechanism of SHTB. The underlying mechanisms were evaluated by enzyme-linked immunosorbent assay (ELISA), western blot analysis, quantitative real time polymerase chain reaction (qPCR) analysis, 16S rRNA high-throughput sequencing, and targeted metabolome analysis. METHODS: HFD-fed mice and db/db mice were orally treated with the standard positive drug metformin (100 mg/kg/d) and with SHTB (200 and 100 mg/kg/d), which was chemically characterized according to the European Medicine Agency (EMA) guidelines. The beneficial effects of SHTB were studied by homeostasis model assessment of insulin resistance (HOMA-IR) index, oral glucose tolerance test (OGTT), insulin tolerance test (ITT), total cholesterol (T-CHO), triglyceride (TG), and inflammation. Subsequently, 16S rDNA-based high-throughput pyrosequencing and GC-MS-based targeted metabolomics profiling were performed to analyze the gut microbiota composition and metabolites profile in the gut, respectively. Moreover, the mammalian target of rapamycin complex 1 (mTORC1) / insulin receptor substrate 1 (IRS-1) / phosphoinositide 3-kinase (PI3K) / protein kinase B (AKT) pathway was evaluated via qPCR and western blot. RESULTS: Chemically characterized SHTB, in which six markers were quantified, effectively alleviated glucose intolerance and IR, ameliorated lipid metabolism dysfunction, and reduced inflammation. In addition, 16S rDNA sequencing found that SHTB reshaped the composition of intestinal flora, as indicated by the enrichment of Akkermansia and Parabacteroides in both HFD-fed and db/db mice. Moreover, SHTB enhanced the intestinal production of short-chain fatty acids (SCFAs) and branched short-chain fatty acids (BSCFAs), and reduced the levels of the fecal and circulating branched-chain amino acids (BCAAs). The IRS-1/PI3K/AKT signaling pathway was upregulated after treatment with SHTB. CONCLUSION: Orally administration of SHTB effectively improved IR and reduced hyperglycemia in mice. Treatment with SHTB regulated the gut BCAAs-mTORC1/IRS-1/PI3K/AKT axis by enhancing the BCAAs catabolism in the gut, which attenuated the deleterious effect of BCAAs on the IRS-1 signaling pathway.


Assuntos
Diabetes Mellitus Tipo 2 , Dieta Hiperlipídica , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Hipoglicemiantes , Resistência à Insulina , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Hipoglicemiantes/farmacologia , Masculino , Dieta Hiperlipídica/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , População do Leste Asiático
10.
Mol Ther Methods Clin Dev ; 32(1): 101194, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38352269

RESUMO

The transfection efficiency and stability of the delivery vehicles of plasmid DNA (pDNA) are critical metrics to ensure high-quality and high-yield production of viral vectors. We previously identified that the optimal size of pDNA/poly(ethylenimine) (PEI) transfection particles is 400-500 nm and developed a bottom-up assembly method to construct stable 400-nm pDNA/PEI particles and benchmarked their transfection efficiency in producing lentiviral vectors (LVVs). Here, we report scale-up production protocols for such transfection particles. Using a two-inlet confined impinging jet (CIJ) mixer with a dual syringe pump set-up, we produced a 1-L batch at a flow rate of 100 mL/min, and further scaled up this process with a larger CIJ mixer and a dual peristaltic pump array, allowing for continuous production at a flow rate of 1 L/min without a lot size limit. We demonstrated the scalability of this process with a 5-L lot and validated the quality of these 400-nm transfection particles against the target product profile, including physical properties, shelf and on-bench stability, transfection efficiency, and LVV production yield in both 15-mL bench culture and 2-L bioreactor runs. These results confirm the potential of this particle assembly process as a scalable manufacturing platform for viral vector production.

11.
ACS Nano ; 18(24): 15729-15743, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38839059

RESUMO

Lipid nanoparticles (LNP) have emerged as pivotal delivery vehicles for RNA therapeutics. Previous research and development usually assumed that LNPs are homogeneous in population, loading density, and composition. Such perspectives are difficult to examine due to the lack of suitable tools to characterize these physicochemical properties at the single-nanoparticle level. Here, we report an integrated spectroscopy-chromatography approach as a generalizable strategy to dissect the complexities of multicomponent LNP assembly. Our platform couples cylindrical illumination confocal spectroscopy (CICS) with single-nanoparticle free solution hydrodynamic separation (SN-FSHS) to simultaneously profile population identity, hydrodynamic size, RNA loading levels, and distributions of helper lipid and PEGylated lipid of LNPs at the single-particle level and in a high-throughput manner. Using a benchmark siRNA LNP formulation, we demonstrate the capability of this platform by distinguishing seven distinct LNP populations, quantitatively characterizing size distribution and RNA loading level in wide ranges, and more importantly, resolving composition-size correlations. This SN-FSHS-CICS analysis provides critical insights into a substantial degree of heterogeneity in the packing density of RNA in LNPs and size-dependent loading-size correlations, explained by kinetics-driven assembly mechanisms of RNA LNPs.


Assuntos
Lipídeos , Nanopartículas , Tamanho da Partícula , Nanopartículas/química , Lipídeos/química , RNA/química , Cromatografia/métodos , RNA Interferente Pequeno/química , Análise Espectral/métodos , Lipossomos
12.
ACS Chem Neurosci ; 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000128

RESUMO

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with exposure to repetitive head impacts, and it is neuropathologically defined as the accumulation of abnormally hyperphosphorylated tau (p-tau). Early detection of p-tau in the brain is of great value in the prevention and treatment of CTE. Previous experimental studies reported that positron emission tomography (PET) technique using several tau tracers are available for imaging certain neurodegenerative diseases. However, few studies have focused on the development of CTE tau tracers. In this work, we performed conventional molecular docking and molecular dynamics simulations to address the binding properties and mechanisms of PET tracers (18F-PM-PBB3, 18F-CBD-2115, 18F-PI-2620, 18F-RO-948, 18F-MK-6240, and 18F-flortaucipir) to CTE tau protofibrils. The results show that the hydrophobic cavity and the top of the concave structure of CTE tau protofibrils are the preferred binding sites for the six tracers, and 18F-PM-PBB3 has the most competitive binding affinity to CTE tau protofibrils. Further investigation into the binding patterns of the six tracers to the CTE tau protofibrils showed that 18F-CBD-2115 and 18F-PM-PBB3 have a high number of H-bonds and hydrophobic contacts with tau protofibrils, resulting in strong hydrogen bonding and hydrophobic interactions; 18F-flortaucipir/18F-PI-2620 and 18F-PI-2620/18F-RO-948 form more intense π-π and cation-π interactions with tau protofibrils, respectively. Subsequently, we conducted a detailed analysis of the binding mechanism of 18F-PM-PBB3 to CTE tau protofibrils. The benzothiazole ring of 18F-PM-PBB3 exhibits stronger π-π stacking and cation-π interactions with tau protofibrils than the pyridine ring and forms a more concentrated T-shaped π-π stacking pattern. This study contributes to understanding the binding mechanism of PET tracers to CTE tau protofibrils and provides new insights into the design of potential novel tracers.

13.
Neurotoxicology ; 95: 94-106, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36669621

RESUMO

OBJECTIVE: To explore the relationship between the proinflammatory factor high-mobility group box 1 (HMGB1) and glutamatergic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in the development of epilepsy. METHODS: Thalamic reticular nucleus (TRN) slices were treated with kainic acid (KA) to simulate seizures. Action potentials and spontaneous inhibitory postsynaptic currents (sIPSCs) were recorded within TRN slices using whole-cell patch clamp techniques. The translocation of HMGB1 was detected by immunofluorescence. The HMGB1/TLR4 signaling pathway and its downstream inflammatory factors (IL-1ß and NF-κB) were detected by RTPCR, Western blot and ELISA. RESULTS: KA-evoked spikings were observed in TRN slices and blocked by perampanel. sIPSCs in the TRN were enhanced by KA and reduced by perampanel. The translocation of HMGB1 in the TRN was promoted by KA and inhibited by perampanel. The expression of the HMGB1/TLR4 signaling pathway was promoted by KA and suppressed by perampanel. CONCLUSION: KA induced hyperexcitability activates the HMGB1/TLR4 pathway, which potentially leading to neuroinflammation in epilepsy.


Assuntos
Epilepsia , Proteína HMGB1 , Humanos , Ácido Caínico/toxicidade , Receptor 4 Toll-Like/metabolismo , Proteína HMGB1/metabolismo , NF-kappa B/metabolismo , Receptores de AMPA/metabolismo
14.
Radiother Oncol ; 189: 109911, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37709053

RESUMO

BACKGROUND AND PURPOSE: Radiation-induced hypothyroidism (RIHT) is a common but underestimated late effect in head and neck cancers. However, no consensus exists regarding risk prediction or dose constraints in RIHT. We aimed to develop a machine learning model for the accurate risk prediction of RIHT based on clinical and dose-volume features and to evaluate its performance internally and externally. MATERIALS AND METHODS: We retrospectively searched two institutions for patients aged >20 years treated with definitive radiotherapy for nasopharyngeal or oropharyngeal cancer, and extracted their clinical information and dose-volume features. One was designated the developmental cohort, the other as the external validation cohort. We compared the performances of machine learning models with those of published normal tissue complication probability (NTCP) models. RESULTS: The developmental and external validation cohorts consisted of 378 and 49 patients, respectively. The estimated cumulative incidence rates of grade ≥1 hypothyroidism were 53.5% and 61.3% in the developmental and external validation cohorts, respectively. Machine learning models outperformed traditional NTCP models by having lower Brier scores at every time point and a lower integrated Brier score, while demonstrating a comparable calibration index and mean area under the curve. Even simplified machine learning models using only thyroid features performed better than did traditional NTCP algorithms. The machine learning models showed consistent performance between folds. The performance in a previously unseen external validation cohort was comparable to that of the cross-validation. CONCLUSIONS: Our model outperformed traditional NTCP models, with additional capabilities of predicting the RIHT risk at individual time points. A simplified model using only thyroid dose-volume features still outperforms traditional NTCP models and can be incorporated into future treatment planning systems for biological optimization.


Assuntos
Neoplasias de Cabeça e Pescoço , Hipotireoidismo , Humanos , Estudos Retrospectivos , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Aprendizado de Máquina
15.
Nat Biomed Eng ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082180

RESUMO

Lipid nanoparticles (LNPs) can be designed to potentiate cancer immunotherapy by promoting their uptake by antigen-presenting cells, stimulating the maturation of these cells and modulating the activity of adjuvants. Here we report an LNP-screening method for the optimization of the type of helper lipid and of lipid-component ratios to enhance the delivery of tumour-antigen-encoding mRNA to dendritic cells and their immune-activation profile towards enhanced antitumour activity. The method involves screening for LNPs that enhance the maturation of bone-marrow-derived dendritic cells and antigen presentation in vitro, followed by assessing immune activation and tumour-growth suppression in a mouse model of melanoma after subcutaneous or intramuscular delivery of the LNPs. We found that the most potent antitumour activity, especially when combined with immune checkpoint inhibitors, resulted from a coordinated attack by T cells and NK cells, triggered by LNPs that elicited strong immune activity in both type-1 and type-2 T helper cells. Our findings highlight the importance of optimizing the LNP composition of mRNA-based cancer vaccines to tailor antigen-specific immune-activation profiles.

16.
Mycology ; 13(3): 185-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35938083

RESUMO

Ophiocordyceps sinensis is a well-known entomogenous fungus with its fruiting bodies or cultural mycelium as food and herbal medicines in Asia. While metabolites which could responsible for its potent pharmaceutical effects has long remained to be elucidated. In this work, chemical investigation on the solid culture of O. sinensis strain LY34 led to the discovery of six digalactosyldiacylglycerols (DGDGS, 1-6) including one new. The structure of compound 1 was determined based on the comprehensive spectra analysis, including NMR, MSn, IR, and chemical derivatisation. Bioactivity studies showed a weak cytotoxicity of compounds 1-6 against 293 T cell and medium anti-inflammatory activity of compounds 1 and 2 on Raw 264.7 cell. The discovery of DGDGs in O. sinensis provides new insight into the pharmacologically active substances.

17.
Nat Commun ; 13(1): 5561, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151112

RESUMO

Lipid nanoparticles (LNPs) are effective vehicles to deliver mRNA vaccines and therapeutics. It has been challenging to assess mRNA packaging characteristics in LNPs, including payload distribution and capacity, which are critical to understanding structure-property-function relationships for further carrier development. Here, we report a method based on the multi-laser cylindrical illumination confocal spectroscopy (CICS) technique to examine mRNA and lipid contents in LNP formulations at the single-nanoparticle level. By differentiating unencapsulated mRNAs, empty LNPs and mRNA-loaded LNPs via coincidence analysis of fluorescent tags on different LNP components, and quantitatively resolving single-mRNA fluorescence, we reveal that a commonly referenced benchmark formulation using DLin-MC3 as the ionizable lipid contains mostly 2 mRNAs per loaded LNP with a presence of 40%-80% empty LNPs depending on the assembly conditions. Systematic analysis of different formulations with control variables reveals a kinetically controlled assembly mechanism that governs the payload distribution and capacity in LNPs. These results form the foundation for a holistic understanding of the molecular assembly of mRNA LNPs.


Assuntos
Lipídeos , Nanopartículas , Lipídeos/química , Lipossomos , Nanopartículas/química , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
18.
Biomed Res Int ; 2020: 4710780, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178826

RESUMO

BACKGROUND: CircRNAs are noncoding RNA molecules that have recently been described and shown to regulate miRNA functionality. While recent studies have suggested such circRNAs to be associated with pain related diseases in humans, no comprehensive migraine-related circRNA profiles have been generated, and there is currently no clear understanding of whether they can serve as regulators of migraine pathology. METHODS: We initially conducted a circRNA microarray analysis of the plasma of migraine patients and healthy controls. Based upon these data, we then selected 8 differentially expressed circRNAs and confirmed their expression in more migraine patient plasma samples via real-time PCR. We then performed functional and pathway enrichment analyses. Lastly, using a robust rank aggregation approach, we constructed a ceRNA network according to predicted circRNA-miRNA and miRNA-mRNA pairs in these migraine patient samples. RESULTS: We were able to detect 2039 circRNAs in our patient samples, with 794 of 1245 these circRNAs being up- and downregulated in migraine patients relative to controls, respectively (fold change ≥ 1.5, p < 0.01). A qRT-PCR analysis confirmed that the expression of hsa_circRNA_100236, hsa_circRNA_102413, and hsa_circRNA_000367 was significantly enhanced in migraine patients, whereas the expression of hsa_circRNA_103809, hsa_circRNA_103670, and hsa_circRNA_101833 was significantly reduced in these individuals relative to healthy controls. We found these differentially regulated circRNAs to be associated with numerous predicted biological processes, with enrichment analyses suggesting that they may modulate the PI3K-Akt signaling so as to promote inflammation to drive migraine development. However, further research will be needed to formally test these mechanistic possibilities and to validate these circRNAs as potential biomarkers of migraine patients. CONCLUSIONS: Our results offer new potential insights into the mechanistic basis of this condition and suggest that hsa_circRNA_000367 and hsa_circRNA_102413 may offer value as regulators of migraine pathology.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Transtornos de Enxaqueca/genética , RNA Circular/genética , Regulação para Baixo/genética , Ontologia Genética , Redes Reguladoras de Genes , Humanos , RNA Circular/metabolismo , Reprodutibilidade dos Testes , Regulação para Cima/genética
19.
Front Neurol ; 11: 159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32265817

RESUMO

Background: Vestibular migraine (VM) is the most common cause of spontaneous vertigo with no specific physical and laboratory examinations, and is an under-recognized entity with substantial burden for the individual and the society. In this study, by observing the brainstem auditory evoked potential (BAEP) and cognitive function of VM patients, the possible laboratory diagnostic indicators of VM and the influence of disease on cognitive function were discussed. Method: The study included 78 VM patients, 76 migraine patients, and 79 healthy individuals. The age, gender, and other clinical history of the three groups matched. All participants underwent BAEP examinations, in which patients in the migraine group and outpatients of the VM group were in the interictal period, and inpatients in the VM group were examined during episodes, while all patients tested for the Addenbrooke's cognitive examination-revised (ACE-R) scale were in the interictal period. The differences in BAEP and ACE-R scores between the three groups of members and their relationship with the clinical features of VM patients were analyzed. Result: The peak latency of I, III, and V wave in the BAEP of the VM group was longer than that of the migraine group and the control group (p < 0.05). The peak latency of V wave in the BAEP of the migraine group was longer than that of the control group (p < 0.05). The ACE-R of the VM group scored lower than the migraine group in terms of language fluency and language (p < 0.05), and lower than the control group in terms of total score, language fluency, language, and visuospatial (p < 0.05); and the ACE-R of the migraine group scored lower than the control group in the total score and visuospatial (p < 0.05). Conclusion: Migraine patients have brainstem dysfunction, and VM patients have more severe brainstem dysfunction than migraine patients, suggesting that VM patients have both central nervous system damage and peripheral nerve damage. Migraine patients have cognitive impairment, while cognitive impairment in VM patients is more severe than in migraine patients.

20.
Anal Cell Pathol (Amst) ; 2020: 8895449, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33415067

RESUMO

BACKGROUND: Oxidized low-density lipoprotein (Ox-LDL) is a crucial pathogenic factor for vascular diseases, which can induce the proliferation of vascular smooth muscle cells (VSMCs). Genistein is the main component of soybean isoflavone. Genistein has a variety of pharmacological properties in the treatment of vascular diseases and a promising clinical application. Large-conductance calcium-activated potassium (BKCa) channels are the primary type of potassium channels in VSMCs, which regulate various biological functions of VSMCs. However, whether genistein exerts an antiproliferation effect on Ox-LDL-stimulated VSMCs remains unclear. The current study is aimed at elucidating the effect of genistein on the Ox-LDL-stimulated proliferation of VSMCs and its possible molecular mechanism, especially the electrophysiological mechanism related to BKCa channels. METHODS: Monoculture VSMC was obtained by an acute enzyme-dispersing method. The proliferation of cells was measured by CCK-8, cell cycle, and proliferating cell nuclear antigen (PCNA) expression. The BKCa whole-cell currents were measured by patch-clamp. RESULTS: Ox-LDL treatment induced the proliferation of VSMCs, upregulated the BKCa protein expression, and increased the density of BKCa currents, while genistein significantly inhibited these effects caused by Ox-LDL. BKCa channels exerted a regulatory role in the proliferation of VSMCs in response to Ox-LDL. The inhibition of BKCa channels suppressed Ox-LDL-stimulated VSMC proliferation, while the activation of BKCa channels showed the opposite effect. Moreover, genistein suppressed the activity of BKCa, including protein expression and current density in a protein tyrosine kinase- (PTK-) dependent manner. CONCLUSION: This study demonstrated that genistein inhibited the Ox-LDL-mediated proliferation of VSMCs by blocking the cell cycle progression; the possible molecular mechanism may be related to PTK-dependent suppression of BKCa channels. Our results provided novel ideas for the application of genistein in the treatment of vascular diseases and proposed a unique insight into the antiproliferative molecular mechanism of genistein.


Assuntos
Genisteína/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Lipoproteínas LDL/farmacologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Animais , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Isoflavonas/farmacologia , Masculino , Miócitos de Músculo Liso/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Tirosina Quinases/metabolismo , Ratos Wistar , Tirfostinas/farmacologia , Vanadatos/farmacologia
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