RESUMO
BACKGROUND: The impact of different stroke types on specific activities of daily living (ADL) is unclear. OBJECTIVE: To investigate how differences between intracerebral hemorrhage (ICH) and cerebral infarction (CI) affect improvement of ADL in patients with stroke within a hospital by focusing on the sub-items of the Functional Independence Measure (FIM). METHODS: Patients with first-stroke hemiplegia (nâ=â212) were divided into two groups: ICH (86 patients) and CI (126 patients). Primary assessments included 13 motor and 5 cognitive sub-items of the FIM assessed at admission and discharge. Between-group comparisons and multiple regression analyses were performed. RESULTS: Upon admission, the ICH group exhibited significantly lower FIM scores than those of the CI group across various activities, including grooming, dressing (upper body and lower body), toileting, bed/chair transfer, toilet transfer, walking/wheelchair, and stairs. Age and FIM motor scores at admission influenced both groups' total FIM motor scores at discharge, whereas the duration from onset affected only the CI group. CONCLUSION: Several individual FIM motor items were more adversely affected by ICH than by CI. Factors related to ADL at discharge may differ depending on stroke type. Recognizing these differences is vital for efficient rehabilitation practices and outcome prediction.
Assuntos
Atividades Cotidianas , Hemorragia Cerebral , Infarto Cerebral , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Idoso , Hemorragia Cerebral/complicações , Hemorragia Cerebral/reabilitação , Estudos Retrospectivos , Infarto Cerebral/reabilitação , Infarto Cerebral/complicações , Pessoa de Meia-Idade , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Idoso de 80 Anos ou mais , Recuperação de Função Fisiológica/fisiologiaRESUMO
Microtubule-associated protein A1/B1-light chain 3 (LC3)-associated phagocytosis (LAP) is a type of non-canonical autophagy that regulates phagosome maturation in macrophages. However, the role and regulatory mechanism of LAP remain largely unknown. Recently, the membrane occupation and recognition nexus repeat-containing-2 (MORN2) was identified as a key component of LAP for the efficient formation of LC3-recruiting phagosomes. To characterize MORN2 and elucidate its function in LAP, we established a MORN2-overexpressing macrophage line. At a steady state, MORN2 was partially cleaved by the ubiquitin-proteasome system. MORN2 overexpression promoted not only LC3-II production but also LAP phagosome (LAPosome) acidification during Escherichia coli uptake. Furthermore, the formation of LAPosomes containing the yeast cell wall component zymosan was enhanced in MORN2-overexpressing cells and depended on reactive oxygen species (ROS). Finally, MORN2-mediated LAP was regulated by plasma membrane-localized soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) such as SNAP-23 and syntaxin 11. Taken together, these findings demonstrate that MORN2, whose expression is downregulated via proteasomal digestion, is a limiting factor for LAP, and that membrane trafficking by SNARE proteins is involved in MORN2-mediated LAP.
Assuntos
Macrófagos/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Fagocitose/fisiologia , Animais , Regulação da Expressão Gênica , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Biológicos , Fagossomos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina/metabolismo , UbiquitinaçãoRESUMO
Syntaxin 11 (stx11) is a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) that is selectively expressed in immune cells; however, its precise role in macrophages is unclear. We showed that stx11 knockdown reduces the phagocytosis of Escherichia coli in interferon-γ-activated macrophages. stx11 knockdown decreased Toll-like receptor 4 (TLR4) localization on the plasma membrane without affecting total expression. Plasma membrane-localized TLR4 was primarily endocytosed within 1 h by lipopolysaccharide (LPS) stimulation and gradually relocalized 4 h after removal of LPS. This relocalization was significantly impaired by stx11 knockdown. The lack of TLR4 transport to the plasma membrane is presumably related to TLR4 degradation in acidic endosomal organelles. Additionally, an immunoprecipitation experiment suggested that stx11 interacts with SNAP-23, a plasma membrane-localized SNARE protein, whose depletion also inhibits TLR4 replenishment in LPS-stimulated cells. Using an intramolecular Förster resonance energy transfer (FRET) probe for SNAP-23, we showed that the high FRET efficiency caused by LPS stimulation is reduced by stx11 knockdown. These findings suggest that stx11 regulates the stimulus-dependent transport of TLR4 to the plasma membrane by cooperating with SNAP-23 in macrophages. Our results clarify the regulatory mechanisms underlying intracellular transport of TLR4 and have implications for microbial pathogenesis and immune responses.
Assuntos
Proteínas Qa-SNARE/metabolismo , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Membrana Celular/metabolismo , Endocitose/fisiologia , Endossomos/metabolismo , Técnicas de Silenciamento de Genes , Macrófagos/metabolismo , Fusão de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose/fisiologia , Ligação Proteica , Transporte Proteico , Proteínas Qa-SNARE/genética , Receptor 4 Toll-Like/genéticaRESUMO
SNAP-23 is a plasma membrane-localized soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) involved in Fc receptor (FcR)-mediated phagocytosis. However, the regulatory mechanism underlying its function remains elusive. Using phosphorylation-specific antibodies, SNAP-23 was found to be phosphorylated at Ser95 in macrophages. To understand the role of this phosphorylation, we established macrophage lines overexpressing the nonphosphorylatable S95A or the phosphomimicking S95D mutation. The efficiency of phagosome formation and maturation was severely reduced in SNAP-23-S95D-overexpressing cells. To examine whether phosphorylation at Ser95 affected SNAP-23 structure, we constructed intramolecular Förster resonance energy transfer (FRET) probes of SNAP-23 designed to evaluate the approximation of the N termini of the two SNARE motifs. Interestingly, a high FRET efficiency was detected on the membrane when the S95D probe was used, indicating that phosphorylation at Ser95 caused a dynamic structural shift to the closed form. Coexpression of IκB kinase (IKK) 2 enhanced the FRET efficiency of the wild-type probe on the phagosome membrane. Furthermore, the enhanced phagosomal FRET signal in interferon-γ-activated macrophages was largely dependent on IKK2, and this kinase mediated a delay in phagosome-lysosome fusion. These results suggested that SNAP-23 phosphorylation at Ser95 played an important role in the regulation of SNARE-dependent membrane fusion during FcR-mediated phagocytosis.
Assuntos
Macrófagos/metabolismo , Fagossomos/metabolismo , Fosfosserina/metabolismo , Proteínas Qb-SNARE/química , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/química , Proteínas Qc-SNARE/metabolismo , Receptores Fc/metabolismo , Humanos , Interferon gama/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Macrófagos/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Modelos Biológicos , Proteínas Mutantes/metabolismo , Fagocitose/efeitos dos fármacos , Fagossomos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Phagosome formation and maturation are essential innate immune mechanisms to engulf and digest foreign particles. To analyze these processes quantitatively, we established a specific Escherichia coli probe expressing a tandem fluorescent protein, comprising glutathione S-transferase fused with monomeric Cherry (mCherry) and monomeric Venus (mVenus). We demonstrated that mVenus was more susceptible to bleaching in an acidic environment than mCherry, and that the mVenus:mCherry fluorescence intensity ratio can be used to monitor phagosomal pH changes during maturation. Using this probe, we revealed that synaptosomal-associated protein of 23 kDa, a plasma membrane soluble N-ethylmaleimide-sensitive factor attachment protein receptor protein, actively regulated phagocytosis of E. coli and subsequent phagosome maturation in macrophages. Our results indicated that this probe has the potential to be a powerful tool in understanding the molecular mechanisms of phagosome formation and maturation.
Assuntos
Escherichia coli/fisiologia , Proteínas Luminescentes/metabolismo , Fagossomos/fisiologia , Animais , Linhagem Celular , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Concentração de Íons de Hidrogênio , Proteínas Luminescentes/genética , Camundongos , Fagocitose/fisiologia , Proteínas Qb-SNARE/genética , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/genética , Proteínas Qc-SNARE/metabolismoRESUMO
Developing new strategies for controlling polymer conformations through precise molecular recognition can potentially generate a machine-like motion that is dependent on molecular information-an important process for the preparation of new intelligent nanomaterials (e.g., polymer-based nanomachines) in the field bordering between polymer chemistry and conventional supramolecular sciences. Herein, we propose a strategy to endow a helical polymer chain with dynamic spring-like (contraction/expansion) motion through the one-dimensional self-assembly (aggregation/disaggregation) of peripheral amphiphilic molecules. In this developing system, we employed a semi-artificial helical polysaccharide presenting peripheral amphiphilic chlorophyll units as a power device that undergoes contractive motion in aqueous media, driven by strong π-π interactions of its chlorophyll units or by cooperative molecular recognition of bipyridyl-type ligands through pairs of chlorophyll units, thereby converting molecular information into the regulated motion of a spring. In addition, this system also undergoes expansive motion through coordination of pyridine. We anticipate that this strategy will be applicable (when combined with the established wrapping chemistry of the helical polysaccharide) to the development of, for example, drug carriers (e.g., nano-syringes), actuators (stimuli-responsive films), and directional transporters (nano-railways), thereby extending the frontiers of supramolecular science.
Assuntos
Clorofila/química , Proteínas de Ligação a DNA/química , Polímeros/química , Polissacarídeos/química , Ligantes , Conformação Molecular , Nanotecnologia , Fenômenos de Química Orgânica , Estrutura Secundária de ProteínaRESUMO
Creation of higher-ordered polymeric architectures composed of alternative assemblies of single-walled carbon nanotubes (SWNTs) and fibrous porphyrin J-aggregates can be easily achieved utilizing the cationic semi-artificial polysaccharide which can act not only as a tubular host for SWNTs but also as a one-dimensional template for porphyrin molecules. This new class of hierarchical polymer assembly is formed, for the first time, by the mutual template effect of two components, i.e., the cationic SWNT complexes and the anionic porphyrin supramolecular nanofibers. In the present system, the self-assembling behaviors of the SWNT complexes as well as the final properties of the SWNT nanoarchitectures are strongly affected by the packing mode of porphyrin molecules on the cationic semi-artificial polysaccharide. Furthermore, we have confirmed that the light energy captured by the porphyrin J-aggregates is effectively transferred to SWNTs.