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1.
Reproduction ; 162(2): 129-139, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34085951

RESUMO

Cilia are evolutionarily conserved microtubule-based structures that perform diverse biological functions. Cilia are assembled on basal bodies and anchored to the plasma membrane via distal appendages. In the male reproductive tract, multicilia in efferent ducts (EDs) move in a whip-like motion to prevent sperm agglutination. Previously, we demonstrated that the distal appendage protein CEP164 recruits Chibby1 (Cby1) to basal bodies to facilitate basal body docking and ciliogenesis. Mice lacking CEP164 in multiciliated cells (MCCs) (FoxJ1-Cre;CEP164fl/fl) show a significant loss of multicilia in the trachea, oviduct, and ependyma. In addition, we observed male sterility; however, the precise role of CEP164 in male fertility remained unknown. Here, we report that the seminiferous tubules and rete testis of FoxJ1-Cre;CEP164fl/fl mice exhibit substantial dilation, indicative of dysfunctional multicilia in the EDs. We found that multicilia were hardly detectable in the EDs of FoxJ1-Cre;CEP164fl/fl mice although FoxJ1-positive immature cells were present. Sperm aggregation and agglutination were commonly noticeable in the lumen of the seminiferous tubules and EDs of FoxJ1-Cre;CEP164fl/fl mice. In FoxJ1-Cre;CEP164fl/fl mice, the apical localization of Cby1 and the transition zone marker NPHP1 was severely diminished, suggesting basal body docking defects. TEM analysis of EDs further confirmed basal body accumulation in the cytoplasm of MCCs. Collectively, we conclude that male infertility in FoxJ1-Cre;CEP164fl/fl mice is caused by sperm agglutination and obstruction of EDs due to loss of multicilia. Our study, therefore, unravels an essential role of the distal appendage protein CEP164 in male fertility.


Assuntos
Diferenciação Celular , Cílios/patologia , Epididimo/patologia , Células Epiteliais/patologia , Infertilidade Masculina/patologia , Proteínas dos Microtúbulos/fisiologia , Túbulos Seminíferos/patologia , Animais , Cílios/metabolismo , Epididimo/metabolismo , Células Epiteliais/metabolismo , Infertilidade Masculina/etiologia , Masculino , Camundongos , Camundongos Knockout , Túbulos Seminíferos/metabolismo
2.
PLoS Genet ; 13(12): e1007128, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29244804

RESUMO

Multiciliated cells of the airways, brain ventricles, and female reproductive tract provide the motive force for mucociliary clearance, cerebrospinal fluid circulation, and ovum transport. Despite their clear importance to human biology and health, the molecular mechanisms underlying multiciliated cell differentiation are poorly understood. Prior studies implicate the distal appendage/transition fiber protein CEP164 as a central regulator of primary ciliogenesis; however, its role in multiciliogenesis remains unknown. In this study, we have generated a novel conditional mouse model that lacks CEP164 in multiciliated tissues and the testis. These mice show a profound loss of airway, ependymal, and oviduct multicilia and develop hydrocephalus and male infertility. Using primary cultures of tracheal multiciliated cells as a model system, we found that CEP164 is critical for multiciliogenesis, at least in part, via its regulation of small vesicle recruitment, ciliary vesicle formation, and basal body docking. In addition, CEP164 is necessary for the proper recruitment of another distal appendage/transition fiber protein Chibby1 (Cby1) and its binding partners FAM92A and FAM92B to the ciliary base in multiciliated cells. In contrast to primary ciliogenesis, CEP164 is dispensable for the recruitment of intraflagellar transport (IFT) components to multicilia. Finally, we provide evidence that CEP164 differentially controls the ciliary targeting of membrane-associated proteins, including the small GTPases Rab8, Rab11, and Arl13b, in multiciliated cells. Altogether, our studies unravel unique requirements for CEP164 in primary versus multiciliogenesis and suggest that CEP164 modulates the selective transport of membrane vesicles and their cargoes into the ciliary compartment in multiciliated cells. Furthermore, our mouse model provides a useful tool to gain physiological insight into diseases associated with defective multicilia.


Assuntos
Cílios/fisiologia , Proteínas dos Microtúbulos/fisiologia , Animais , Corpos Basais/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Centríolos/metabolismo , Cílios/genética , Cílios/metabolismo , Células Epiteliais/citologia , Feminino , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas dos Microtúbulos/genética , Proteínas dos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Transporte Proteico , Traqueia/citologia
3.
J Cell Physiol ; 234(2): 1871-1879, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30063079

RESUMO

The canonical Wnt-ß-catenin pathway is important in normal development. Mutations in ß-catenin or proteins involved with regulating its phosphorylation or localization result in its nuclear accumulation where it activates its target genes and stimulates cell proliferation. This pathway is dysregulated in many different types of cancer, including gastric cancer (GC). Chibby (Cby) is a 14-kDa protein that inhibits ß-catenin localization to the nucleus and represses ß-catenin-induced transcriptional activity. In the current study, we examined the expression and function of Cby in normal and cancerous human gastric tissue. Reverse-transcription polymerase chain reaction and immunohistochemistry revealed that Cby is expressed in human stomach and localized to glandular elements. Immunohistochemical staining intensity of Cby was decreased in GC tissue when compared with normal gastric epithelium. In AGS cells, a human gastric carcinoma cell line, Cby expression was low. Stable AGS cell transfectants overexpressing Cby were prepared. Cby overexpression did not affect proliferation rates or ß-catenin levels. However, confocal microscopy and subcellular fractionation studies revealed that Cby overexpression resulted in a small decrease in nuclear ß-catenin. Moreover, Cby overexpression caused a molecular weight shift in nuclear ß-catenin and resulted in decreased ß-catenin signaling in AGS cells as measured by the TopFlash assay. However, Cby overexpression did not affect c-Myc protein levels. To conclude, Cby expression was decreased in GC samples and Cby expression altered ß-catenin localization in cultured GC cells. However, Cby did not affect cell proliferation rates or ß-catenin-induced protein expression. Cby may be involved in the early events in the pathogenesis of GC.


Assuntos
Adenocarcinoma/metabolismo , Proteínas de Transporte/metabolismo , Mucosa Gástrica/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Gástricas/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Nucleares/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , beta Catenina/genética
4.
Colloids Surf B Biointerfaces ; 238: 113916, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636438

RESUMO

The ureteral stent is an effective treatment for clinical ureteral stricture following urological surgery, and the functional coating of the stent could effectively inhibit bacterial colonization and other complications. The present review provides an analysis and description of the materials used in ureteral stents and their coatings. Emphasis is placed on the technological advancements of functional coatings, taking into consideration the characteristics of these materials and the properties of their active substances. Furthermore, recent advances in enhancing the therapeutic efficacy of functional coatings are also reviewed. It is anticipated that this article will serve as a valuable reference providing insights for future research development on new drug-loaded ureteral stents.


Assuntos
Materiais Revestidos Biocompatíveis , Polímeros , Stents , Ureter , Humanos , Ureter/cirurgia , Polímeros/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Animais
5.
ACS Biomater Sci Eng ; 10(2): 791-799, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38153906

RESUMO

As for the deep tissue infections of chronic osteomyelitis, antibiotics are hard to deliver into the infected bone tissue, which makes it difficult to be cured completely in clinic. Microwave has strong penetration, and the medium can produce a good bactericidal effect through the microwave thermal effect (MTE). Here, a new microwave sensitizer (Fe3O4@APNs) was prepared and evaluated. Black phosphorus nanosheets modified with phytic acid dodecasodium (APNs) were fabricated by a liquid-phase exfoliation method that exhibited good water oxygen stability. A complex with Fe3O4 compound and APNs (Fe3O4@APNs) was formed by an ultrasonic mixing process, which showed excellent MTE (quickly increased to 53.5 °C in 5 min at 2.45 GHz, 10 W/cm2) via dielectric versus magnetic loss (reflect loss value of -5.94 dB at 2.45 GHz). The Fe3O4@APNs microwave sensitizer developed in this study has an outstanding in vitro antibacterial effect and might show promise for the treatment of chronic osteomyelitis enabled by local tissue heating via the MTE.


Assuntos
Micro-Ondas , Osteomielite , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Osso e Ossos , Ácido Fítico
6.
J Cell Biol ; 223(3)2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38197861

RESUMO

Proper compartmentalization of the sperm flagellum is essential for fertility. The annulus is a septin-based ring that demarcates the midpiece (MP) and the principal piece (PP). It is assembled at the flagellar base, migrates caudally, and halts upon arriving at the PP. However, the mechanisms governing annulus positioning remain unknown. We report that a Chibby3 (Cby3)/Cby1-interacting BAR domain-containing 1 (ciBAR1) complex is required for this process. Ablation of either gene in mice results in male fertility defects, caused by kinked sperm flagella with the annulus mispositioned in the PP. Cby3 and ciBAR1 interact and colocalize to the annulus near the curved membrane invagination at the flagellar pocket. In the absence of Cby3, periannular membranes appear to be deformed, allowing the annulus to migrate over the fibrous sheath into the PP. Collectively, our results suggest that the Cby3/ciBAR1 complex regulates local membrane properties to position the annulus at the MP/PP junction.


Assuntos
Proteínas de Transporte , Proteínas Nucleares , Sêmen , Cauda do Espermatozoide , Espermatogênese , Animais , Masculino , Camundongos , Cílios , Citoesqueleto , Espermatogênese/genética , Proteínas Nucleares/genética , Proteínas de Transporte/genética
7.
Nat Genet ; 34(3): 308-12, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12778173

RESUMO

Mice lacking the transcriptional repressor oncoprotein Gfi1 are unexpectedly neutropenic. We therefore screened GFI1 as a candidate for association with neutropenia in affected individuals without mutations in ELA2 (encoding neutrophil elastase), the most common cause of severe congenital neutropenia (SCN; ref. 3). We found dominant negative zinc finger mutations that disable transcriptional repressor activity. The phenotype also includes immunodeficient lymphocytes and production of a circulating population of myeloid cells that appear immature. We show by chromatin immunoprecipitation, gel shift, reporter assays and elevated expression of ELA2 in vivo in neutropenic individuals that GFI1 represses ELA2, linking these two genes in a common pathway involved in myeloid differentiation.


Assuntos
Proteínas de Ligação a DNA/genética , Elastase de Leucócito/genética , Mutação de Sentido Incorreto , Neutropenia/genética , Fatores de Transcrição , Adulto , Idoso , Pré-Escolar , Cromossomos/imunologia , Ensaio de Unidades Formadoras de Colônias , Feminino , Humanos , Lactente , Luciferases/metabolismo , Masculino , Neutropenia/sangue , Neutropenia/etiologia , Neutrófilos/enzimologia , Linhagem , Testes de Precipitina , Regiões Promotoras Genéticas , Proto-Oncogene Mas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Dedos de Zinco
8.
Nat Genet ; 35(1): 90-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12897784

RESUMO

Cyclic hematopoiesis is a stem cell disease in which the number of neutrophils and other blood cells oscillates in weekly phases. Autosomal dominant mutations of ELA2, encoding the protease neutrophil elastase, found in lysosome-like granules, cause cyclic hematopoiesis and most cases of the pre-leukemic disorder severe congenital neutropenia (SCN; ref. 3) in humans. Over 20 different mutations of neutrophil elastase have been identified, but their consequences are elusive, because they confer no consistent effects on enzymatic activity. The similar autosomal recessive disease of dogs, canine cyclic hematopoiesis, is not caused by mutations in ELA2 (data not shown). Here we show that homozygous mutation of the gene encoding the dog adaptor protein complex 3 (AP3) beta-subunit, directing trans-Golgi export of transmembrane cargo proteins to lysosomes, causes canine cyclic hematopoiesis. C-terminal processing of neutrophil elastase exposes an AP3 interaction signal responsible for redirecting neutrophil elastase trafficking from membranes to granules. Disruption of either neutrophil elastase or AP3 perturbs the intracellular trafficking of neutrophil elastase. Most mutations in ELA2 that cause human cyclic hematopoiesis prevent membrane localization of neutrophil elastase, whereas most mutations in ELA2 that cause SCN lead to exclusive membrane localization.


Assuntos
Complexo 3 de Proteínas Adaptadoras/genética , Doenças do Cão/genética , Elastase de Leucócito/genética , Mutação , Neutropenia/genética , Neutrófilos/enzimologia , Complexo 3 de Proteínas Adaptadoras/metabolismo , Animais , Membrana Celular/enzimologia , Doenças do Cão/enzimologia , Cães , Hematopoese , Humanos , Dados de Sequência Molecular , Neutropenia/enzimologia , Linhagem , Sinais Direcionadores de Proteínas , Transporte Proteico
9.
Yao Xue Xue Bao ; 47(1): 131-4, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22493818

RESUMO

This study is undertaken to modify the chitosan nanoparticles (CS-NPs) with wheat germ agglutinin (WGA), and investigate the conjugation between WGA-CS-NPs and N-acetylglucosamine (NAG). CS-NPs were prepared by ionotropic gelation process and then conjugated with WGA under the activation of glutaricdialdehyde. The mean diameter of the CS-NPs was approximately 113.5 nm and the poly-dispersity index (PDI) was 0.18. The binding yield of WGA to CS-NPs was comprised between 27.8% and 87.9% depending mostly on the addition of 0.3% (w/v) glutaraldehyde solution. A competitive inhibition experiment of WGA-CS-NPs to bovine submaxillary gland mucin (BSM) was taken to illuminate the binding activity of WGA-CS-NPs to the sugar of N-acetylglucosamine. After the addition of NAG, the binding rates between CS-NPs and BSM almost didn't change, while the binding rates between WGA-CS-NPs and BSM dropped down significantly, which confirmed the specific binding characteristics of WGA to NAG.


Assuntos
Acetilglucosamina/química , Quitosana/química , Aglutininas do Germe de Trigo/química , Acetilglucosamina/metabolismo , Quitosana/metabolismo , Sistemas de Liberação de Medicamentos , Mucinas/metabolismo , Nanopartículas , Tamanho da Partícula , Ligação Proteica , Aglutininas do Germe de Trigo/metabolismo
10.
Cells ; 11(3)2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35159149

RESUMO

Cilia are microtubule-based hair-like organelles on the cell surface. Cilia have been implicated in various biological processes ranging from mechanosensation to fluid movement. Ciliary dysfunction leads to a plethora of human diseases, known as ciliopathies. Although non-motile primary cilia are ubiquitous, motile multicilia are found in restricted locations of the body, such as the respiratory tract, the oviduct, the efferent duct, and the brain ventricles. Multicilia beat in a whip-like motion to generate fluid flow over the apical surface of an epithelium. The concerted ciliary motion provides the driving force critical for clearing airway mucus and debris, transporting ova from the ovary to the uterus, maintaining sperm in suspension, and circulating cerebrospinal fluid in the brain. In the male reproductive tract, multiciliated cells (MCCs) were first described in the mid-1800s, but their importance in male fertility remained elusive until recently. MCCs exist in the efferent ducts, which are small, highly convoluted tubules that connect the testis to the epididymis and play an essential role in male fertility. In this review, we will introduce multiciliogenesis, discuss mouse models of male infertility with defective multicilia, and summarize our current knowledge on the biological function of multicilia in the male reproductive tract.


Assuntos
Epididimo , Infertilidade Masculina , Animais , Epididimo/metabolismo , Feminino , Fertilidade , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Espermatozoides , Testículo/metabolismo
11.
Sci Rep ; 11(1): 17220, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446743

RESUMO

Primary cilia protrude from the apical surface of many cell types and act as a sensory organelle that regulates diverse biological processes ranging from chemo- and mechanosensation to signaling. Ciliary dysfunction is associated with a wide array of genetic disorders, known as ciliopathies. Polycystic lesions are commonly found in the kidney, liver, and pancreas of ciliopathy patients and mouse models. However, the pathogenesis of the pancreatic phenotype remains poorly understood. Chibby1 (Cby1), a small conserved coiled-coil protein, localizes to the ciliary base and plays a crucial role in ciliogenesis. Here, we report that Cby1-knockout (KO) mice develop severe exocrine pancreatic atrophy with dilated ducts during early postnatal development. A significant reduction in the number and length of cilia was observed in Cby1-KO pancreta. In the adult Cby1-KO pancreas, inflammatory cell infiltration and fibrosis were noticeable. Intriguingly, Cby1-KO acinar cells showed an accumulation of zymogen granules (ZGs) with altered polarity. Moreover, isolated acini from Cby1-KO pancreas exhibited defective ZG secretion in vitro. Collectively, our results suggest that, upon loss of Cby1, concomitant with ciliary defects, acinar cells accumulate ZGs due to defective exocytosis, leading to cell death and progressive exocrine pancreatic degeneration after birth.


Assuntos
Proteínas de Transporte/genética , Cílios/metabolismo , Pâncreas Exócrino/metabolismo , Pâncreas/metabolismo , Pancreatite/genética , Células Acinares/metabolismo , Animais , Atrofia , Proteínas de Transporte/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Exocitose/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pâncreas/patologia , Pâncreas/ultraestrutura , Pâncreas Exócrino/patologia , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
12.
Mol Cell Biol ; 27(12): 4347-54, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17403895

RESUMO

The canonical Wnt/beta-catenin signaling pathway plays diverse roles in embryonic development and disease. Activation of this pathway, likely by Wnt-10b, has been shown to inhibit adipogenesis in cultured 3T3-L1 preadipocytes and in mice. Here, we report that the beta-catenin antagonist Chibby (Cby) is required for adipocyte differentiation. Cby is expressed in adipose tissue in mice, and Cby protein levels increase during adipogenic differentiation of 3T3-L1 cells. Ectopic expression of Cby induces spontaneous differentiation of these cells into mature adipocytes to an extent similar to that of dominant-negative Tcf-4. In contrast, depletion of Cby by RNA interference potently blocks adipogenesis of 3T3-L1 and mouse embryonic stem cells. In support of this, embryonic fibroblasts obtained from Cby-deficient embryos display attenuated differentiation to the adipogenic lineage. Mechanistically, Cby promotes adipocyte differentiation, in part by inhibiting beta-catenin, since gain or loss of function of Cby influences beta-catenin signaling in 3T3-L1 cells. Our results therefore establish Cby as a novel proadipogenic factor required for adipocyte differentiation.


Assuntos
Adipócitos/fisiologia , Proteínas de Transporte/fisiologia , Diferenciação Celular , Proteínas Nucleares/fisiologia , beta Catenina/antagonistas & inibidores , Células 3T3-L1 , Adipogenia , Animais , Proteínas de Transporte/genética , Linhagem Celular , Células Cultivadas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Genes Reporter , Histocitoquímica , Humanos , Luciferases/metabolismo , Camundongos , Proteínas Nucleares/genética , Interferência de RNA , Transdução de Sinais
13.
Yao Xue Xue Bao ; 45(7): 914-9, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20931792

RESUMO

This study is to prepare scopolamine hydrobromide nanoparticles-in-microsphere system (SH-NiMS) and evaluate its drug release characteristics in vitro. SH nanoparticles were prepared by ionic crosslinking method with tripolyphosphate (TPP) as crosslinker and chitosan as carrier. Orthogonal design was used to optimize the formulation of SH nanoparticles, which took the property of encapsulation efficiency and drug loading as evaluation parameters. With HPMC as carrier, adjusted the parameters of spray drying technique and sprayed the SH nanoparticles in microspheres encaposulated by HPMC was formed and which is called nanoparticles-in-microsphere system (NiMS). SH-NiMS appearances were observed by SEM, structure was obsearved by FT-IR and the release characteristics in vitro were evaluated. The optimized formulation of SH nanoparticles was TPP/CS 1:3 (w/w), HPMC 0.3%, SH 0.2%. The solution peristaltic speed of the spray drying technique was adjusted to 15%, and the temperature of inlet was 110 degrees C. The encapsulation product yeild, drug loading and particle sizes of SH-NiMS were 94.2%, 20.4%, and 1256.5 nm, respectively. The appearances and the structure of SH-NiMS were good. The preparation method of SH-NiMS is stable and reliable to use, which provide a new way to develop new dosage form.


Assuntos
Composição de Medicamentos/métodos , Escopolamina/administração & dosagem , Quitosana/química , Reagentes de Ligações Cruzadas , Preparações de Ação Retardada , Portadores de Fármacos/química , Microscopia Eletrônica de Varredura , Microesferas , Nanopartículas/química , Tamanho da Partícula , Polifosfatos/química , Escopolamina/química , Espectroscopia de Infravermelho com Transformada de Fourier
14.
BMC Mol Biol ; 10: 41, 2009 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-19435523

RESUMO

BACKGROUND: The Wnt/beta-catenin signaling pathway plays crucial roles in embryonic development and in maintenance of organs and tissues in adults. Chibby (Cby) is an evolutionarily conserved molecule that physically interacts with the key downstream coactivator beta-catenin and represses its transcriptional activation potential. Although Cby harbors a predicted coiled-coil motif in the C-terminal region, its molecular nature and functional importance remain largely unexplored. RESULTS: Here we report that Cby forms a stable complex with itself. Alanine substitutions of two or more of four critical leucine residues within the C-terminal heptad repeats completely eliminate the Cby-Cby interaction. The Cby oligomer predominantly exists as a homodimer. Furthermore, we found that dimerization-deficient Cby mutants still retain the ability to bind to beta-catenin and to repress beta-catenin-dependent gene activation. More importantly, Cby homodimerization is required for its efficient interaction with the nuclear import receptor importin-alpha and subsequent nuclear translocation. CONCLUSION: Our comprehensive mutational analysis of the Cby coiled-coil domain reveals that the four heptad leucine residues play an essential role in mediating Cby homodimerization. Although monomeric Cby is sufficient to bind to beta-catenin and block beta-catenin-mediated transcriptional activation, homodimer formation of Cby is indispensable for its efficient nuclear import.


Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Leucina/química , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Transporte Ativo do Núcleo Celular , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Transporte/genética , Linhagem Celular , Dimerização , Humanos , Leucina/genética , Leucina/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares/genética , Ligação Proteica , Transporte Proteico , Alinhamento de Sequência , Ativação Transcricional , alfa Carioferinas/genética , alfa Carioferinas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
15.
J Pharm Pharmacol ; 61(9): 1155-61, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19703364

RESUMO

OBJECTIVES: The aim was to prepare neoglycoprotein-based nanoparticles for targeted drug delivery to hepatic stellate cells, and to evaluate their characteristics in vitro and in vivo. METHODS: The neoglycoprotein of bovine serum albumin modified with mannose 6-phosphate was synthesised from mannose, and used as wall material to nanoencapsulate the model natural antifibrotic substance sodium ferulate using a desolvation method. The morphology, drug loading capacity, release in vitro and biodistribution in vivo of the nanoparticles were studied. Selectivity of the nanoparticles for hepatic stellate cells was evaluated by immunohistochemical analysis of fibrotic rat liver sections. KEY FINDINGS: The spherical nanoparticles were negatively charged with zeta potential ranging from -2.73 to -35.85 mV, and sizes between 100 and 200 nm with a narrow size distribution. Drug entrapment efficiency of about 90% (w/w) and loading capacity of 20% (w/w) could be achieved. in vitro, the nanoparticles showed an initial rapid continuous release followed by a slower sustained release. After intravenous injection into mice, the nanoparticles showed a slower elimination rate and a much higher drug concentration in liver compared with the sodium ferrate solution, and less distribution to the kidneys and other tissues. Immunohistochemistry indicated that the neoglycoprotein-based nanoparticles were taken up specifically by hepatic stellate cells. CONCLUSIONS: The nanoparticles may be an efficient drug carrier targeting hepatic stellate cells.


Assuntos
Ácidos Cumáricos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Cirrose Hepática/tratamento farmacológico , Manosefosfatos/administração & dosagem , Nanopartículas/administração & dosagem , Soroalbumina Bovina/administração & dosagem , Animais , Ácidos Cumáricos/farmacocinética , Portadores de Fármacos/farmacocinética , Glicoproteínas/administração & dosagem , Glicoproteínas/síntese química , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Masculino , Manosefosfatos/química , Camundongos , Ratos , Soroalbumina Bovina/química , Distribuição Tecidual
16.
Biomed Chromatogr ; 23(7): 692-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19309751

RESUMO

A sensitive and selective LC-MS/MS method was developed and validated for the determination of aconitine in microdialysate and rat plasma. Extraction of plasma sample was conducted by use of 1% trichloracetic acid and acetonitrile solution with 10 ng/mL internal standard (propafenone) spiked. Microdialysates were analyzed without sample purification. After sample preparation, 2 microL were injected and separated with an isocratic mobile phase consisting of acetonitrile:0.1% formic acid (60:40, v/v) at a flow rate of 0.3 mL/min. The Agilent G6410A triple quadrupole LC/MS system was operated under the multiple-reaction monitoring mode (MRM) using the electrospray ionization technique in positive mode. Overall, the assay exhibited good precision and accuracy. The diffusion properties of aconitine investigated in in vitro microdialysis experiments revealed unfavourable concentration dependence avertable by keeping a constant pH 5.77 using isotonic phosphate buffer solution as perfusate. The mean relative recoveries were 48.23% [coefficient of variation (CV 4.47%)] and 55.38% (CV 2.89%) for retrodialysis and recovery experiments, respectively. The in vivo recovery of aconitine was 34.48% (CV 3.05%) and was stable over the 6 h study period. Following characterization of aconitine both in vitro and in vivo microdialysis, the developed setting is suitable for application in pharmacokinetics and pharmacodynamics studies.


Assuntos
Aconitina/análise , Aconitina/sangue , Cromatografia Líquida de Alta Pressão/métodos , Soluções para Diálise/química , Espectrometria de Massas em Tandem/métodos , Animais , Calibragem , Interpretação Estatística de Dados , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Modelos Lineares , Microdiálise/métodos , Propafenona/sangue , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Chem Pharm Bull (Tokyo) ; 57(10): 1045-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19801856

RESUMO

Focused on the natural biodegradable material of chitosan (CS), this investigation concerned its spray-dried nanoparticles-in-microparticles (NiMPs) modified with ulex europaeus agglutinin (UEA). Chitosan nanoparticles were obtained by ionotropic gelation process with pentasodium tripolyphosphate as gelatinizer. Then UEA lectin was bound onto the CS nanoparticles activated by glutaraldehyde. The conjugated spherical UEA-CS-NiMPs, prepared by spray drying method, exhibited 12-85% coupling efficiency of UEA depending upon the amount of activator glutaraldehyde. And the UEA-grafted particles showed additional higher binding tendency with bovine submaxillary gland mucin as compared to the plain chitosan microparticles. Furthermore, the activity and intrinsic fucose-specificity of UEA were still maintained after the covalent modification. It is thus evident that the UEA anchored CS-NiMPs might be used as a potential drug delivery system targeted to the specific regions of gastrointestinal tract.


Assuntos
Aglutininas/metabolismo , Quitosana/química , Mucinas/metabolismo , Nanopartículas/química , Glândula Submandibular/metabolismo , Ulex/metabolismo , Animais , Bovinos , Portadores de Fármacos/química , Glutaral/química , Ligação Proteica
18.
Circulation ; 115(5): 617-26, 2007 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-17261658

RESUMO

BACKGROUND: Embryonic stem cell (ESC)-derived cardiomyocytes are anticipated to serve as a useful source for future cell-based cardiovascular disease therapies. Research emphasis is currently focused on determining methods to direct the differentiation of ESCs to a large population of cardiomyocytes with high purity. To this aim, understanding the molecular mechanisms that control ESC-to-cardiomyocyte differentiation should play a critical role in the development of this methodology. The Wnt/beta-catenin signaling pathway has been implicated in both embryonic cardiac development and in vitro ESC differentiation into cardiomyocytes. Chibby is a recently identified nuclear protein that directly binds to beta-catenin and antagonizes its transcriptional activity. METHODS AND RESULTS: Chibby was ubiquitously expressed in early stages of ESC differentiation but upregulated during cardiomyocyte specification. Of interest, the Chibby gene promoter has multiple binding sites for the cardiac-specific homeodomain protein Nkx2.5, and its promoter activity was indeed positively regulated by Nkx2.5. Furthermore, overexpression of Chibby increased cardiac differentiation of ESCs, whereas loss of Chibby by RNAi impaired cardiomyocyte differentiation. CONCLUSIONS: These data illustrate the regulation and function of Chibby in facilitating cardiomyocyte differentiation from ESCs. By revealing molecular mechanisms that control ESC-to-cardiomyocyte differentiation, this study will allow for the future development of technologies to improve cardiomyocyte differentiation from ESCs.


Assuntos
Proteínas de Transporte/fisiologia , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Proteínas Nucleares/fisiologia , Transdução de Sinais/fisiologia , Proteínas Wnt/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Animais , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Diferenciação Celular/genética , Linhagem Celular , Linhagem Celular Transformada , Regulação para Baixo/genética , Células-Tronco Embrionárias/fisiologia , Humanos , Camundongos , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Transdução de Sinais/genética , Proteínas Wnt/biossíntese , Proteínas Wnt/genética , beta Catenina/biossíntese , beta Catenina/genética
19.
Int J Pharm ; 349(1-2): 274-82, 2008 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-17870261

RESUMO

Sodium ferulate (SF) loaded nanoparticles were prepared by desolvation procedure and subsequent cross-linking of the wall material of bovine serum albumin (BSA). Several factors in the nanoencapsulation process, such as the addition rate of the desolvation agent, composition of BSA and SF solution, amount of the cross-linker glutaraldehyde, were investigated to elucidate their influences on the particle size, zeta potential, drug loading and encapsulation efficiency of the resulted nanoparticles. The obtained spherical nanoparticles were negative charged with zeta potential from -20 to -40 mV, and characterized between 100 and 200 nm with a narrow size distribution. In the condition of introducing 1.0 mL 8% glutareldehyde per mg of BSA, the drug entrapment efficiency (EE) of 80% (w/w) and loading capacity of about 16% (w/w) could be achieved for the cross-linked BSA nanoparticles with SF encapsulated (SF-BSA-NP). And the drug EE was decreased along with the increasing amount of glutareldehyde used for cross-linking. The in vitro drug release properties of SF-BSA-NP behaved with an initial burst effect and then sustained-release stage. To some extent, the drug release rate could be adjusted by cross-linking with different amount of glutaraldehyde. Compared with SF solution, SF-BSA-NP showed a much higher drug distribution into liver and a lower drug concentration in other tissues, after intravenously injected to mice. So, BSA based nanoparticles might be a suitable controlled released carrier for the freely water-soluble drug SF and further hepatic targeted drug delivery.


Assuntos
Ácidos Cumáricos/administração & dosagem , Fibrinolíticos/administração & dosagem , Fígado/efeitos dos fármacos , Soroalbumina Bovina/química , Animais , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacocinética , Reagentes de Ligações Cruzadas , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Eletroquímica , Etanol/química , Fibrinolíticos/química , Fibrinolíticos/farmacocinética , Indicadores e Reagentes , Camundongos , Microscopia Eletrônica de Transmissão , Nanopartículas , Tamanho da Partícula , Solubilidade , Solventes/química , Distribuição Tecidual
20.
Yao Xue Xue Bao ; 43(4): 383-7, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18664200

RESUMO

To investigate the effect of cetirizine hydrochloride on the expression of neurokinin 1 receptor (NK-1R) and cytokines production induced by substance P (SP) in HaCaT cells (a human epidermal keratinocyte cell line) and dermal fibroblasts. The effect of cetirizine on the expression of NK-1R protein was detected by flow cytometry and Western blotting analysis. The modulation of cetirizine on the production of interferon (IFN)-gamma, interleukin (IL)-1beta, IL-6 and IL-8 in HaCaT cells and fibroblasts was measured by ELISA. The results showed that cetirizine significantly inhibited the expression of NK-1R in HaCaT cells and fibroblasts. SP induced the production of IFN-gamma, IL-1beta and IL-8 in both cell types. Cetirizine 1-100 micromol x L(-1) inhibited SP-induced IL-1beta and IL-8 production in HaCaT cells and fibroblasts, while had no effect on the production of IFN-gamma in both cells. Both SP and cetirizine had no effect on the secretion of IL-6 in HaCaT cells and fibroblasts. These findings suggest that cetirizine may be involved in the treatment of SP-induced skin inflammation by inhibiting the expression of substance P receptor and regulation the production of IL-1beta and IL-8 in epidermal keratinocyte and dermal fibroblasts.


Assuntos
Cetirizina/farmacologia , Fibroblastos/metabolismo , Interleucina-1beta/metabolismo , Queratinócitos/metabolismo , Receptores da Neurocinina-1/metabolismo , Antialérgicos/farmacologia , Linhagem Celular , Fibroblastos/citologia , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Humanos , Interferon gama/metabolismo , Interleucina-8/metabolismo , Queratinócitos/citologia , Substância P/farmacologia
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