RESUMO
Ordered two-dimensional arrays such as S-layers1,2 and designed analogues3-5 have intrigued bioengineers6,7, but with the exception of a single lattice formed with flexible linkers8, they are constituted from just one protein component. Materials composed of two components have considerable potential advantages for modulating assembly dynamics and incorporating more complex functionality9-12. Here we describe a computational method to generate co-assembling binary layers by designing rigid interfaces between pairs of dihedral protein building blocks, and use it to design a p6m lattice. The designed array components are soluble at millimolar concentrations, but when combined at nanomolar concentrations, they rapidly assemble into nearly crystalline micrometre-scale arrays nearly identical to the computational design model in vitro and in cells without the need for a two-dimensional support. Because the material is designed from the ground up, the components can be readily functionalized and their symmetry reconfigured, enabling formation of ligand arrays with distinguishable surfaces, which we demonstrate can drive extensive receptor clustering, downstream protein recruitment and signalling. Using atomic force microscopy on supported bilayers and quantitative microscopy on living cells, we show that arrays assembled on membranes have component stoichiometry and structure similar to arrays formed in vitro, and that our material can therefore impose order onto fundamentally disordered substrates such as cell membranes. In contrast to previously characterized cell surface receptor binding assemblies such as antibodies and nanocages, which are rapidly endocytosed, we find that large arrays assembled at the cell surface suppress endocytosis in a tunable manner, with potential therapeutic relevance for extending receptor engagement and immune evasion. Our work provides a foundation for a synthetic cell biology in which multi-protein macroscale materials are designed to modulate cell responses and reshape synthetic and living systems.
Assuntos
Desenho de Fármacos , Engenharia de Proteínas , Proteínas/síntese química , Proteínas/metabolismo , Células 3T3 , Animais , Biologia Celular , Sobrevivência Celular , Biologia Computacional , Endocitose , Escherichia coli/genética , Escherichia coli/metabolismo , Técnicas In Vitro , Cinética , Ligantes , Camundongos , Microscopia de Força Atômica , Modelos Moleculares , Biologia SintéticaRESUMO
This study extracted and purified a polysaccharide from Rehmanniae radix praeparata (RGP) with an average molecular weight. The structural characteristics of RGP and its ironâ (III) complex, RGP-Fe(III), were examined for their antioxidant properties and potential in treating iron deficiency anemia (IDA). Analysis revealed that RGP comprised Man, Rha, Gal, and Xyl, with a sugar residue skeleton featuring 1â3; 1â2, 3; and 1â2, 3, 4 linkages, among others. RGP-Fe(III) had a molecular weight of 4.39×104â Da. Notably, RGP-Fe(III) exhibited superior antioxidant activity compared to RGP alone. In IDA rat models, treatment with RGP-Fe(III) led to increased weight gain, restoration of key blood parameters including hemoglobin, red blood cells, and mean hemoglobin content, elevated serum iron levels, and decreased total iron-binding capacity. Histological examination revealed no observable toxic effects of RGP-Fe(III) on the liver and spleen. These findings suggest the potential of RGP-Fe(III) as a therapeutic agent for managing IDA and highlight its promising antioxidant properties.
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Anemia Ferropriva , Antioxidantes , Polissacarídeos , Rehmannia , Animais , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Rehmannia/química , Ratos , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Anemia Ferropriva/tratamento farmacológico , Compostos Férricos/química , Masculino , Ferro/química , Baço/efeitos dos fármacos , Ratos Sprague-Dawley , Fígado/efeitos dos fármacos , Fígado/metabolismo , Modelos Animais de DoençasRESUMO
OBJECTIVES: To screen biomarkers for forensic identification of acute myocardial infarction (AMI) by non-targeted metabolomic studies on changes of urine metabolites in rats with AMI. METHODS: The rat models of the sham surgery group, AMI group and hyperlipidemia + acute myocardial infarction (HAMI) group were established. Ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) was used to analyze the changes of urine metabolic spectrometry in AMI rats. Principal component analysis, partial least squares-discriminant analysis, and orthogonal partial least squares-discriminant analysis were used to screen differential metabolites. The MetaboAnalyst database was used to analyze the metabolic pathway enrichment and access the predictive ability of differential metabolites. RESULTS: A total of 40 and 61 differential metabolites associated with AMI and HAMI were screened, respectively. Among them, 22 metabolites were common in both rat models. These small metabolites were mainly concentrated in the niacin and nicotinamide metabolic pathways. Within the 95% confidence interval, the area under the curve (AUC) values of receiver operator characteristic curve for N8-acetylspermidine, 3-methylhistamine, and thymine were greater than 0.95. CONCLUSIONS: N8-acetylspermidine, 3-methylhistamine, and thymine can be used as potential biomarkers for AMI diagnosis, and abnormal metabolism in niacin and nicotinamide may be the main causes of AMI. This study can provide reference for the mechanism and causes of AMI identification.
Assuntos
Biomarcadores , Modelos Animais de Doenças , Metabolômica , Infarto do Miocárdio , Animais , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/urina , Ratos , Metabolômica/métodos , Masculino , Biomarcadores/urina , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão , Ratos Sprague-Dawley , Análise de Componente Principal , Análise Discriminante , Espectrometria de Massas/métodos , Niacina/metabolismo , Niacina/urina , Hiperlipidemias/metabolismo , Niacinamida/urina , Niacinamida/metabolismo , Niacinamida/análogos & derivados , Redes e Vias Metabólicas , Curva ROC , Análise dos Mínimos Quadrados , Medicina Legal/métodos , MetabolomaRESUMO
The folding of proteins into intricate three-dimensional structures to achieve biological functions, such as catalysis, is governed by both kinetic and thermodynamic controls. The quest to design artificial enzymes using minimalist peptides seeks to emulate supramolecular structures existing in a catalytically active state. Drawing inspiration from the nuanced process of protein folding, our study explores the enzyme-like activity of amphiphilic peptide nanosystems in both equilibrium and non-equilibrium states, featuring the formation of supramolecular nanofibrils and nanosheets. In contrast to thermodynamically stable nanosheets, the kinetically trapped nanofibrils exhibit dynamic characteristics (e.g., rapid molecular exchange and relatively weak intermolecular packing), resulting in a higher hydrolase-mimicking activity. We emphasize that a supramolecular microenvironment characterized by an optimal local polarity, microviscosity, and ß-sheet hydrogen bonding is conducive to both substrate binding and ester bond hydrolysis. Our work underscores the pivotal role of both thermodynamic and kinetic control in impacting biomimetic catalysis and sheds a light on the development of artificial enzymes.
Assuntos
Hidrolases , Peptídeos , Peptídeos/química , Proteínas , Dobramento de Proteína , TermodinâmicaRESUMO
PURPOSE: Human post mortem studies have described the topographical patterns of tau pathology in progressive supranuclear palsy (PSP). Recent advances in tau PET tracers are expected to herald the next era of PSP investigation for early detection of tau pathology in living brains. This study aimed to investigate whether 18F-Florzolotau PET imaging may capture the distribution patterns and regional vulnerability of tau pathology in PSP, and to devise a novel image-based staging system. METHODS: The study cohort consisted of 148 consecutive patients with PSP who had undergone 18F-Florzolotau PET imaging. The PSP rating scale (PSPrs) was used to measure disease severity. Similarities and differences of tau deposition among different clinical phenotypes were examined at the regional and voxel levels. An 18F-Florzolotau pathological staging system was devised according to the scheme originally developed for post mortem data. In light of conditional probabilities for the sequence of events, an 18F-Florzolotau modified staging system by integrating clusters at the regional level was further developed. The ability of 18F-Florzolotau staging systems to reflect disease severity in terms of PSPrs score was assessed by analysis of variance. RESULTS: The distribution patterns of 18F-Florzolotau accumulation in living brains of PSP showed a remarkable similarity to those reported in post mortem studies, with the binding intensity being markedly higher in Richardson's syndrome. Moreover, 18F-Florzolotau PET imaging allowed detecting regional vulnerability and tracking tau accumulation in an earlier fashion compared with post mortem immunostaining. The 18F-Florzolotau staging systems were positively correlated with clinical severity as reflected by PSPrs scores. CONCLUSIONS: 18F-Florzolotau PET imaging can effectively capture the distribution patterns and regional vulnerability of tau pathology in PSP. The 18F-Florzolotau modified staging system holds promise for early tracking of tau deposition in living brains.
Assuntos
Paralisia Supranuclear Progressiva , Humanos , Encéfalo/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Proteínas tau/metabolismoRESUMO
BACKGROUND: Recent development in tau-sensitive tracers has sparkled significant interest in tracking tauopathies using positron emission tomography (PET) biomarkers. However, the ability of 18 F-florzolotau PET imaging to topographically characterize tau pathology in corticobasal syndrome (CBS) remains unclear. Further, the question as to whether disease-level differences exist with other neurodegenerative tauopathies is still unanswered. OBJECTIVE: To analyze the topographical patterns of tau pathology in the living brains of patients with CBS using 18 F-florzolotau PET imaging and to examine whether differences with other tauopathies exist. METHODS: 18 F-florzolotau PET imaging was performed in 20 consecutive patients with CBS, 20 cognitively healthy controls (HCs), 20 patients with Alzheimer's disease (AD), and 16 patients with progressive supranuclear palsy-Richardson's syndrome (PSP-RS). Cerebrospinal fluid (CSF) levels of ß-amyloid biomarkers were quantified in all patients with CBS. 18 F-florzolotau uptake was quantitatively assessed using standardized uptake value ratios. RESULTS: Of the 20 patients with CBS, 19 (95%) were negative for CSF biomarkers of amyloid pathology; of them, three had negative 18 F-florzolotau PET findings. Compared with HCs, patients with CBS showed increased 18 F-florzolotau signals in both cortical and subcortical regions. In addition, patients with CBS were characterized by higher tracer retentions in subcortical regions compared with those with AD and showed a trend toward higher signals in cortical areas compared with PSP-RS. An asymmetric pattern of 18 F-florzolotau uptake was associated with an asymmetry of motor severity in patients with CBS. CONCLUSIONS: In vivo 18 F-florzolotau PET imaging holds promise for distinguishing CBS in the spectrum of neurodegenerative tauopathies. © 2023 International Parkinson and Movement Disorder Society.
Assuntos
Degeneração Corticobasal , Tomografia por Emissão de Pósitrons , Tauopatias , Humanos , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Degeneração Corticobasal/diagnóstico por imagem , Radioisótopos de Flúor , Tomografia por Emissão de Pósitrons/métodos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Proteínas tau/metabolismo , Tauopatias/diagnóstico por imagemRESUMO
A new insulin-like growth factor (Igf) subtype 3 (igf3) has recently been found in the bony fish orange-spotted grouper (Epinephelus coioides). However, the role of igf3 in the maturation of the ovary and sex differentiation in E. coioides is currently unknown. We examined the ovarian localization and receptor binding of the novel ortholog Igf3 using qRT-PCR, and Western blotting, combined with in situ hybridization and immunohistochemistry methods. Results demonstrated the presence of igf3 mRNA and protein in mature oocytes. Furthermore, Igf3 protein expression was not detected in testis, brain, kidney and liver homogenates. The calculated molecular weight of Igf3 was 22 kDa, which was consistent with the deduced amino acid sequence from the full-length open reading frame. The immunoreactivity showed that Igf3 was strongly present in the follicle staining fully-grown stage. The igf3 mRNA expression level was significantly positively correlated with ovarian follicular maturation. Meanwhile, Igf3 increased germinal-vesicle breakdown in a time- and dose-dependent manner. In vitro, treatment of primary ovarian cells with Igf3 up-regulated significantly the mRNA expression level of genes related to sex determination and reproduction such as forkhead boxl2 (foxl2), dosage-sensitive sex reversal adrenal hypoplasia critical region on chromosome x gene 1 (dax1), cytochrome P450 family 19 subfamily member 1 a (cyp19a1a), cytochrome P450 family 11 subfamily a member 1 a (cyp11a1a) and luteinizing hormone receptor 1 (lhr1). Overall, our results demonstrated that igf3 promotes the maturation of the ovary and plays an important role in sex differentiation in E. coioides.
Assuntos
Bass , Somatomedinas , Animais , Masculino , Feminino , Bass/genética , Bass/metabolismo , Ovário/metabolismo , Diferenciação Sexual/genética , Somatomedinas/metabolismo , RNA Mensageiro/genética , Clonagem Molecular , Proteínas de Peixes/metabolismoRESUMO
Exposure to solar UV irradiation damages γ-crystallin, leading to cataract formation via aggregation. α-Crystallin, as a small heat shock protein, efficiently suppresses this irreversible aggregation by selectively binding the denatured γ-crystallin monomer. In this study, liquid chromatography tandem mass spectrometry was used to evaluate UV-325 nm irradiation-induced photodamage of human γD-crystallin in the presence of bovine α-crystallin, atomic force microscope (AFM) and dynamic light scattering (DLS) techniques were used to detect the quaternary structure changes of the α-crystallin oligomer, and Fourier transform infrared spectroscopy and temperature-jump nanosecond time-resolved IR absorbance difference spectroscopy were used to probe the secondary structure changes of bovine α-crystallin. We find that the thermal-induced subunit dissociation of the α-crystallin oligomer involves the breaking of hydrogen bonds at the dimeric interface, leading to three different spectral components at varied temperature regions as resolved from temperature-dependent IR spectra. Under UV-325 nm irradiation, unfolded γD-crystallin binds to the dissociated α-crystallin subunit to form an αγ-complex, then follows the reassociation of the αγ-complex to the partially dissociated α-crystallin oligomer. This prevents the aggregation of denatured γD-crystallin. The formation of the γD-bound α-crystallin oligomer is further confirmed by AFM and DLS analysis, which reveals an obvious size expansion in the reassociated αγ-oligomers. In addition, UV-325 nm irradiation causes a peptide bond cleavage of γD-crystallin at Ala158 in the presence of α-crystallin. Our results suggest a very effective protection mechanism for subunits dissociated from α-crystallin oligomers against UV irradiation-induced aggregation of γD-crystallin, at the expense of a loss of a short C-terminal peptide in γD-crystallin.
Assuntos
alfa-Cristalinas , gama-Cristalinas , Animais , Bovinos , Humanos , Chaperonas Moleculares/metabolismo , Dobramento de Proteína , Estrutura Secundária de Proteína , alfa-Cristalinas/metabolismo , gama-Cristalinas/químicaRESUMO
BACKGROUND: Anecdotal evidence suggests that patients diagnosed with the parkinsonian subtype of multiple system atrophy (MSA-P) may show uptake of the second-generation tau positron emission tomography (PET) tracer 18 F-Florzolotau (previously known as 18 F-APN-1607) in the putamen. OBJECTIVES: This study systematically investigated the localization and magnitude of 18 F-Florzolotau uptake in a relatively large cohort of patients with MSA-P. METHODS: 18 F-Florzolotau PET imaging was performed in 31 patients with MSA-P, 24 patients with Parkinson's disease (PD), and 20 age-matched healthy controls. 18 F-Florzolotau signal in the striatum was analyzed by visual inspection and classified as either positive or negative. Regional 18 F-Florzolotau binding was also expressed as standardized uptake value ratio (SUVR) to assess whether it was associated with core symptoms of MSA-P after adjustment for potential confounders. RESULTS: By visual inspection and semiquantitative SUVR comparisons, patients with MSA-P showed elevated 18 F-Florzolotau uptake in the putamen, globus pallidus, and dentate-a finding that was not observed in PD. This increased signal was significantly associated with the core symptoms of MSA-P. In addition, patients with MSA-P with cerebellar ataxia showed an elevated 18 F-Florzolotau uptake in the cerebellar dentate. CONCLUSIONS: 18 F-Florzolotau tau PET imaging findings may reflect the clinical severity of MSA-P and can potentially discriminate between this condition and PD. © 2022 International Parkinson and Movement Disorder Society.
Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Fluordesoxiglucose F18/metabolismo , Humanos , Atrofia de Múltiplos Sistemas/diagnóstico , Doença de Parkinson/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Putamen/metabolismo , Tomografia Computadorizada por Raios XRESUMO
Enzymatic suicide inactivation, a route of permanent enzyme inhibition, is the mechanism of action for a wide array of pharmaceuticals. Here, we developed the first nanosensor that selectively reports the suicide inactivation pathway of an enzyme. The sensor is based on modulation of the near-infrared fluorescence of an enzyme-bound carbon nanotube. The nanosensor responded selectively to substrate-mediated suicide inactivation of the tyrosinase enzyme via bathochromic shifting of the nanotube emission wavelength. Mechanistic investigations revealed that singlet oxygen generated by the suicide inactivation pathway induced the response. We used the nanosensor to quantify the degree of enzymatic inactivation by measuring response rates to small molecule tyrosinase modulators. This work resulted in a new capability of interrogating a specific route of enzymatic death. Potential applications include drug screening and hit-validation for compounds that elicit or inhibit enzymatic inactivation and single-molecule measurements to assess population heterogeneity in enzyme activity.
Assuntos
Monofenol Mono-Oxigenase , Nanotubos de Carbono , Fluorescência , Humanos , Cinética , Monofenol Mono-Oxigenase/metabolismo , NanotecnologiaRESUMO
Redox tailoring enzymes play key roles in generating structural complexity and diversity in typeâ II polyketides. In chartreusin biosynthesis, the early 13 C-labeling experiments and bioinformatic analysis suggest the unusual aglycone is originated from a tetracyclic anthracyclic polyketide. Here, we demonstrated that the carbon skeleton rearrangement from a linear anthracyclic polyketide to an angular pentacyclic biosynthetic intermediate requires two redox enzymes. The flavin-dependent monooxygenase ChaZ catalyses a Baeyer-Villiger oxidation on resomycin C to form a seven-membered lactone. Subsequently, a ketoreductase ChaE rearranges the carbon skeleton and affords the α-pyrone containing pentacyclic intermediate in an NADPH-dependent manner via tandem reactions including the reduction of the lactone carbonyl group, Aldol-type reaction, followed by a spontaneous γ-lactone ring formation, oxidation and aromatization. Our work reveals an unprecedented function of a ketoreductase that contributes to generate structural complexity of aromatic polyketide.
RESUMO
The mangrove-derived endophytic fungus Peniophora incarnata Z4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1-4), one new chromone (5), one new xanthone (6), and one new xanthone dimer (7), together with one known compound, globosuxanthone B (8). Their structures were determined by an extensive analysis of 1D and 2D NMR, HRESIMS, ECD, and single-crystal X-ray diffraction data. In cytotoxic activity assays, compound 2 showed cytotoxicity against three carcinoma cell lines with IC50 values less than 10 µM.
Assuntos
Basidiomycota , Estrutura Molecular , Xantonas , Antineoplásicos , Cromonas , Cristalografia por Raios X , EndófitosRESUMO
Herein we show that by appending bulky ß-cyclodextrin (CD) groups onto sheet-forming peptoids, we obtain cylindrical micelles that further assembly into membranes and intertwined ribbons on substrates in aqueous solution, depending on the choice of solution and substrate conditions. Inâ situ atomic force microscopy (AFM) shows that micelle assembly occurs in two steps, starting with "precursor" particles that transform into worm-like micelles, which extend and coalesce to form the higher order structures with a rate and a degree of cooperativity dependent on pH and Ca2+ concentration. After co-assembly with hydrophobic 4-(2-hydroxyethylamino)-7-nitro-2,1,3-benzoxadiazole (NBD) donors that occupy the hydrophobic core, followed by exposure to hydrophilic Rhodamineâ B as acceptors that insert into cyclodextrin, the micelles exhibit highly efficient Förster resonance energy transfer efficiency in aqueous solution, thereby mimicking natural light harvesting systems.
RESUMO
Two-step nucleation pathways in which disordered, amorphous, or dense liquid states precede the appearance of crystalline phases have been reported for a wide range of materials, but the dynamics of such pathways are poorly understood. Moreover, whether these pathways are general features of crystallizing systems or a consequence of system-specific structural details that select for direct versus two-step processes is unknown. Using atomic force microscopy to directly observe crystallization of sequence-defined polymers, we show that crystallization pathways are indeed sequence dependent. When a short hydrophobic region is added to a sequence that directly forms crystalline particles, crystallization instead follows a two-step pathway that begins with the creation of disordered clusters of 10-20 molecules and is characterized by highly non-linear crystallization kinetics in which clusters transform into ordered structures that then enter the growth phase. The results shed new light on non-classical crystallization mechanisms and have implications for the design of self-assembling polymer systems.
Assuntos
Materiais Biomiméticos/química , Modelos Químicos , Modelos Moleculares , Peptidomiméticos/química , Cristalização , CinéticaAssuntos
Selegilina , Paralisia Supranuclear Progressiva , Humanos , Selegilina/farmacologia , Selegilina/uso terapêutico , Paralisia Supranuclear Progressiva/tratamento farmacológico , Inibidores da Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/uso terapêutico , Proteínas tau , Monoaminoxidase , Tomografia por Emissão de PósitronsRESUMO
Neuroinflammation involves in the progression of many central nervous system diseases. Several studies have shown that histone deacetylase (HDAC) inhibitors modulated inflammatory responses in lipopolysaccharide (LPS) stimulated microglia. While, the mechanism is still unclear. The aim of present study was to investigate the effect of HDAC2 inhibitor CAY10683 on inflammatory responses and TLR4/NF-κB signaling pathways in LPS activated BV2 microglial cells and LPS induced mice neuroinflammation. The effect of CAY10683 on cell viability of BV2 microglial cells was detected by CCK-8 assay. The expressions of inflammatory cytokines were analyzed by western blotting and RT-PCR respectively. The TLR4 protein expression was measured by western blotting, immunofluorescence, immunohistochemistry respectively. The protein expressions of MYD88, phospho-NF-κB p65, NF-κB-p65, acetyl-H3 (AH3), H3, and HDAC2 were analyzed by western blotting. We found that CAY10683 could inhibit expression levels of inflammatory cytokine TNF-α and IL-1ß in LPS activated BV2 microglial cells and LPS induced mice neuroinflammation. It could induce TLR4, MYD88, phospho-NF-κB p65, and HDAC2 expressions. Moreover, CAY10683 increased the acetylation of histones H3 in LPS activated BV2 microglial cells and LPS induced mice neuroinflammation. Taken together, our findings suggested that HDAC2 inhibitor CAY10683 could suppress neuroinflammatory responses and TLR4/NF-κB signaling pathways by acetylation after LPS stimulation.
Assuntos
Histona Desacetilase 2/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Mediadores da Inflamação/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , NF-kappa B/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Linhagem Celular , Histona Desacetilase 2/metabolismo , Mediadores da Inflamação/metabolismo , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , NF-kappa B/metabolismo , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismoRESUMO
The purpose of this study was to investigate the protective mechanism of HDAC2 inhibitor CAY10683 on intestinal mucosal barrier in acute liver failure (ALF). In order to establish ALF-induced intestinal epithelial barrier disruption models, D-galactosamine/LPS and LPS were, respectively, used with rats and NCM460 cell and then administrated with CAY10683. Transepithelial electrical resistance (TEER) was measured to detect the permeability of cells. Real-time PCR and Western blotting were employed to detect the key mRNA and protein levels. The intestinal epithelial tissue pathology was detected. After interfering with CAY10683, the mRNA and protein levels of TLR4, MyD88, TRIF, and TRAF6 were decreased compared with model group (P < 0.05), whereas the levels of ZO-1 and occluding were elevated (P < 0.05). The permeability was elevated in CAY10683-interfered groups, when compared with model group (P < 0.05). And the degree of intestinal epithelial tissue pathological damage in CAY10683 group was significantly reduced. Moreover, CAY10683 significantly decreased the TLR4 staining in animal tissue. The HDAC2 inhibitor CAY10683 could promote the damage of intestinal mucosal barrier in ALF through inhibiting LPS/TLR4/MyD88 pathway.
Assuntos
Inibidores Enzimáticos/uso terapêutico , Lipopolissacarídeos/toxicidade , Falência Hepática Aguda/tratamento farmacológico , Falência Hepática Aguda/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Galactosamina/toxicidade , Histona Desacetilase 2/antagonistas & inibidores , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Falência Hepática Aguda/induzido quimicamente , Ratos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
PURPOSE: Constraint-induced movement therapy (CIMT) can improve motor functions in stroke patients and ischemic rats. This study examined the effect of CIMT in ischemic rats using positron emission tomography (PET). METHODS: We used middle cerebral artery occlusion (MCAO) procedure to induce cerebral ischemia in rats. Male rats were divided into a negative control group (Normal, n = 4), a sham-operated group (Sham, n = 6), an ischemic group (Control, n = 6) and an ischemic CIMT-treated group (CIMT, n = 6). CIMT started at postoperative day 8 (d8) and lasted for 2 weeks. We utilized 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG) micro PET/CT imaging to evaluate glucose metabolism in different brain regions at baseline, before, and after treatment, respectively. RESULTS: CIMT improved behavioral performance in the ischemic CIMT group. At the end of treatment, the CIMT group showed lower standardized uptake values (SUVs) in the ipsilateral cingulate, motor and somatosensory cortex, respectively; as well as the anterodorsal hippocampus compared to the Control group (1.80% ± 0.10% vs. 1.92% ± 0.08%, 1.32% ± 0.14% vs. 1.48% ± 0.09%, 1.18% ± 0.14% vs. 1.42% ± 0.15%, 1.68% ± 0.09% vs. 1.79% ± 0.06%, P < 0.05). We also observed higher SUVs in the acbcore shell and cortex insular of the contralateral hemisphere compared to the Control group (2.07% group in the acbcore shell and cortex insular of contralateral P < 0.05). CONCLUSION: CIMT improved behavioral outcomes in cerebral ischemic rats and this effect can be attributed to increased glucose utilization in the contralateral hemisphere.
Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/reabilitação , Encéfalo/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Restrição Física/métodos , Animais , Circulação Cerebrovascular/fisiologia , Modelos Animais de Doenças , Fluordesoxiglucose F18 , Glucose/metabolismo , Infarto da Artéria Cerebral Média , Masculino , Desempenho Psicomotor , Ratos , Ratos Sprague-Dawley , CaminhadaRESUMO
BACKGROUND: Histone deacetylases (HDACs) inhibitors are new anti-fibrotic drugs that inhibit the activity of hepatic stellate cells. The present study focused on the anti-fibrotic function of HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) by suppressing transforming growth factor-ß1 (TGF-ß1) signaling. METHODS: Male Sprague-Dawley rats were used to induce liver fibrosis with carbon tetrachloride (CCl4) and LX2 cell (human hepatic stellate cell line) was stimulated by TGF-ß1. Both animals and cells were treated with SAHA. The Smad7 and connective tissue growth factor (CTGF) mRNA levels were detected by real-time polymerase chain reaction (PCR). Western blotting was used to examine the protein levels of CTGF, Histone H3 (H3), Smad7, Smad2/3, Acetyl-Histone H3 (AH3), HDAC2, α-smooth muscle actin (α-SMA), HDAC6, p-Smad2/3 and HDAC8. In addition, the TGF-ß1 and liver enzyme levels from rat serum were detected. Histopathological changes were examined by hematoxylin and eosin (HE), Sirius red and Masson trichrome staining. The α-SMA expression was detected by immumohistochemical staining. RESULTS: Compared with control group, the TGF-ß1 and liver enzyme levels from rat serum, together with the mRNA levels of CTGF and protein levels of CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were elevated in fibrotic rats (Pâ¯<â¯0.01). But the Smad7 mRNA and AH3 protein levels were notably suppressed in the fibrotic rats (Pâ¯<â¯0.01). Pathological examination showed the typical changes of liver fibrosis in the fibrotic rats. After the treatment with SAHA, the levels of liver enzymes, TGF-ß1, CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were reduced (Pâ¯<â¯0.01) and Smad7 and AH3 protein contents were elevated in liver fibrotic rats (Pâ¯<â¯0.01). Moreover, immumohistochemistry showed that SAHA significantly suppressed the α-SMA protein content in fibrotic liver (Pâ¯<â¯0.01). CONCLUSION: The HDAC inhibitor SAHA alleviated liver fibrosis by suppressing the TGF-ß1 signaling.