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1.
Gels ; 10(7)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39057494

RESUMO

Hydrogels are one of the most commonly used materials in our daily lives, which possess crosslinked three-dimensional network structures and are capable of absorbing large amounts of fluid. Due to their outstanding properties, such as flexibility, tunability, and biocompatibility, hydrogels have been widely employed in biomedical research and clinics, especially in on-demand drug release. However, traditional hydrogels face various limitations, e.g., the delivery of hydrophobic drugs due to their highly hydrophilic interior environment. Therefore, micelle-containing hydrogels have been designed and developed, which possess both hydrophilic and hydrophobic microenvironments and enable the storage of diverse cargos. Based on the functionalities of micelles, these hydrogels can be classified into micelle-doped and chemically/physically crosslinked types, which were reported to be responsive to varied stimuli, including temperature, pH, irradiation, electrical signal, magnetic field, etc. Here, we summarize the research advances of micelle-containing hydrogels and provide perspectives on their applications in the biomedical field based on the recent studies from our own lab and others.

2.
Analyst ; 149(15): 3980-3988, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38872436

RESUMO

To overcome limitations in the generalizability and efficiency of current AAV vectors, in this current study, we constructed an AAV variant library by the insertion of random heptapeptide sequences in the receptor-binding domain of the AAV9 capsid gene. We then applied a recently developed organ-on-a-chip in vitro model of the human blood-brain barrier (BBB) to iteratively enrich for variants that efficiently cross the BBB and transduce astrocyte cells. Through multiple rounds of screening, we obtained two candidate AAV variants, AAV-M6 and AAV-M8, which showed significantly higher BBB penetration efficiency than AAV9 or AAV-PHP.eB. Quantitative PCR (qPCR) assay showed that AAV-M6 could accumulate to a 5 times higher titer, while AAV-M8 reached a 3 times higher titer, than AAV-PHP.eB in the neural chamber of the model. The transduction assay further verified that the AAV-M6 candidate vector was able to infect HA-1800 cells after crossing the BBB, suggesting it could potentially transduce brain parenchymal cells after crossing the hCMEC/D3 layer at higher efficiency than AAV-PHP.eB. Molecular simulations suggested that the human receptor proteins, LY6D and M6PR, could bind the AAV-M6 heptapeptide insertion with high affinity. This study provides two promising candidate AAV vectors and demonstrates the use of this in vitro BBB model for scalable, high-throughput screening of gene therapies. These tools can drive investigations of the mechanisms underlying BBB permeability and the cell-type specificity of virus vectors.


Assuntos
Barreira Hematoencefálica , Dependovirus , Vetores Genéticos , Barreira Hematoencefálica/metabolismo , Humanos , Dependovirus/genética , Dependovirus/química , Vetores Genéticos/genética , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas do Capsídeo/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Dispositivos Lab-On-A-Chip , Transdução Genética/métodos , Linhagem Celular , Astrócitos/metabolismo , Sistemas Microfisiológicos
3.
J Am Chem Soc ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848464

RESUMO

Histone monoaminylation (i.e., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin.

4.
J Proteome Res ; 23(7): 2651-2660, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838187

RESUMO

Histone dopaminylation is a newly identified epigenetic mark that plays a role in the regulation of gene transcription, where an isopeptide bond is formed between the fifth amino acid of H3 (i.e., glutamine) and dopamine. Recently, we developed a chemical probe to specifically label and enrich histone dopaminylation via bioorthogonal chemistry. Given this powerful tool, we found that histone H3 glutamine 5 dopaminylation (H3Q5dop) was highly enriched in colorectal tumors, which could be attributed to the high expression level of its regulator, transglutaminase 2 (TGM2), in colon cancer cells. Due to the enzyme promiscuity of TGM2, nonhistone proteins have also been identified as dopaminylation targets; however, the dopaminylated proteome in cancer cells still remains elusive. Here, we utilized our chemical probe to enrich dopaminylated proteins from colorectal cancer cells in a bioorthogonal manner and performed the chemical proteomics analysis. Therefore, 425 dopaminylated proteins were identified, many of which are involved in nucleic acid metabolism and transcription pathways. More importantly, a number of dopaminylation sites were identified and attributed to the successful application of our chemical probe. Overall, these findings shed light on the significant association between cellular protein dopaminylation and cancer development, further suggesting that targeting these pathways may become a promising anticancer strategy.


Assuntos
Neoplasias Colorretais , Histonas , Proteína 2 Glutamina gama-Glutamiltransferase , Proteômica , Humanos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Proteômica/métodos , Proteína 2 Glutamina gama-Glutamiltransferase/metabolismo , Histonas/metabolismo , Transglutaminases/metabolismo , Transglutaminases/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética , Linhagem Celular Tumoral , Proteoma/análise , Proteoma/metabolismo , Processamento de Proteína Pós-Traducional , Glutamina/metabolismo , Glutamina/química , Epigênese Genética
5.
bioRxiv ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38766043

RESUMO

Serotonylation has been identified as a novel protein post-translational modification (PTM) for decades, where an isopeptide bond is formed between the glutamine residue and serotonin through transamination. Transglutaminase 2 (also known as TGM2 or TGase2) was proven to act as the main writer enzyme for this PTM and a number of key regulatory proteins (including small GTPases, fibronectin, fibrinogen, serotonin transporter, and histone H3) have been characterized as the substrates of serotonylation. However, due to the lack of pan-specific antibody for serotonylated glutamine, the precise enrichment and proteomic profiling of serotonylation still remain challenging. In our previous research, we developed an aryldiazonium probe to label protein serotonylation in a bioorthogonal manner. This chemical biology tool can be utilized alternatively for the antibody-free enrichment of serotonylated proteins, which depends on a pH-controlled chemoselective rapid azo-coupling reaction (CRACR). Here, we report the application of a photoactive aryldiazonium-biotin probe for the global profiling of serotonylation proteome in cancer cells. Thus, over 500 serotonylated proteins were identified from HCT 116 cells. Importantly, a number of modification sites of these serotonylated proteins were determine, attributed to the successful application of our chemical proteomic approach. Overall, these findings provided new insights into the significant association between cellular protein serotonylation and cancer development, further suggesting that to target TGM2-mediated monoaminylation may serve as a promising strategy for cancer therapeutics.

6.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712070

RESUMO

Histone dopaminylation is a newly identified epigenetic mark that plays a role in the regulation of gene transcription, where an isopeptide bond is formed between the fifth amino acid residue of H3 ( i.e. , glutamine) and dopamine. In our previous studies, we discovered that the dynamics of this post-translational modification (including installation, removal, and replacement) were regulated by a single enzyme, transglutaminase 2 (TGM2), through reversible transamination. Recently, we developed a chemical probe to specifically label and enrich histone dopaminylation via bioorthogonal chemistry. Given this powerful tool, we found that histone H3 glutamine 5 dopaminylation (H3Q5dop) was highly enriched in colorectal tumors, which could be attributed to the high expression level of TGM2 in colon cancer cells. Due to the enzyme promiscuity of TGM2, non-histone proteins have also been identified as targets of dopaminylation on glutamine residues, however, the dopaminylated proteome in cancer cells still remains elusive. Here, we utilized our chemical probe to enrich dopaminylated proteins from colorectal cancer cells in a bioorthogonal manner and performed the chemical proteomics analysis. Therefore, 425 dopaminylated proteins were identified, many of which are involved in nucleic acid metabolism and transcription pathways. More importantly, a number of modification sites of these dopaminylated proteins were identified, attributed to the successful application of our chemical probe. Overall, these findings shed light on the significant association between cellular protein dopaminylation and cancer development, further suggesting that to block the installation of protein dopaminylation may become a promising anti-cancer strategy.

7.
bioRxiv ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38562869

RESUMO

Histone monoaminylation ( i . e ., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin.

8.
Cancer Biol Ther ; 24(1): 2240084, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37498047

RESUMO

Recent evidence has shown that the human microbiome is associated with various diseases, including cancer. The salivary microbiome, fecal microbiome, and circulating microbial DNA in blood plasma have all been used experimentally as diagnostic biomarkers for many types of cancer. The microbiomes present within local tissue, other regions, and tumors themselves have been shown to promote and restrict the development and progression of cancer, most often by affecting cancer cells or the host immune system. These microbes have also been shown to impact the efficacy of various cancer therapies, including radiation, chemotherapy, and immunotherapy. Here, we review the research advances focused on how microbes impact these different facets and why they are important to the clinical care of cancer. It is only by better understanding the roles these microbes play in the diagnosis, development, progression, and treatment of cancer, that we will be able to catch and treat cancer early.


Assuntos
Microbiota , Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Imunoterapia
9.
ACS Appl Mater Interfaces ; 15(13): 17113-17122, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36946793

RESUMO

Electro-responsive dynamic hydrogels, which possess robust mechanical properties and precise spatiotemporal resolution, have a wide range of applications in biomedicine and energy science. However, it is still challenging to design and prepare electro-responsive hydrogels (ERHs) which have all of these properties. Here, we report one such class of ERHs with these features, based on the direct current voltage (DCV)-induced rearrangement of sodium dodecyl sulfate (SDS) micelles, where the rearrangement can tune the hydrogel networks that are originally maintained by the SDS micelle-assisted hydrophobic interactions. An enlarged mesh size is demonstrated for these ERHs after DCV treatment. Given the unique structure and properties of these ERHs, hydrophobic cargo (thiostrepton) has been incorporated into the hydrogels and is released upon DCV loading. Additionally, these hydrogels are highly stretchable (>6000%) and tough (507 J/m2), showing robust mechanical properties. Moreover, these hydrogels have a high spatiotemporal resolution. As the cross-links within our ERHs are enabled by the non-covalent (i.e., hydrophobic) interactions, these hydrogels are self-healing and malleable. Considering the robust mechanical properties, precise spatiotemporal resolution, dynamic nature (e.g., injectable and self-healing), and on-demand drug delivery ability, this class of ERHs will be of great interest in the fields of wearable bioelectronics and smart drug delivery systems.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Hidrogéis/química , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos , Micelas
10.
Heart Surg Forum ; 26(2): E174-E177, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36972600

RESUMO

BACKGROUND: Ascending aortic aneurysm accompanied with stanford type A aortic dissection is a life-threatening condition. The most common presenting symptom is pain. Here, we report a very rare case of giant asymptomatic ascending aortic aneurysm accompanied with chronic stanford type A aortic dissection. CASE PRESENTATION: A 72-year-old woman was founded to have ascending aortic dilation on a routine physical examination. On admission, CTA showed an ascending aortic aneurysm accompanied with stanford type A aortic dissection, the diameter of which was approximately 10 cm. Transthoracic echocardiography showed an ascending aortic aneurysm, aortic sinus and sinus junction dilation, moderate aortic valve regurgitation, left ventricle enlargement, left ventricular wall hypertrophy, and mitral and tricuspid valve mild regurgitation. The patient underwent surgical repair in our department, was discharged, and recovered well. CONCLUSION: This was a very rare case of a giant asymptomatic ascending aortic aneurysm accompanied with chronic stanford type A aortic dissection that was successfully managed by total aortic arch replacement.


Assuntos
Aneurisma da Aorta Ascendente , Aneurisma da Aorta Torácica , Aneurisma Aórtico , Dissecção Aórtica , Insuficiência da Valva Aórtica , Feminino , Humanos , Idoso , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/cirurgia , Aneurisma Aórtico/complicações , Aneurisma Aórtico/diagnóstico , Aneurisma Aórtico/cirurgia , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/cirurgia , Insuficiência da Valva Aórtica/complicações
11.
Macromol Rapid Commun ; 44(8): e2300008, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36807445

RESUMO

Gas-releasing/scavenging hydrogels have wide applications in biomedical and industrial fields. However, the covalently crosslinked nature of these existing materials makes them difficult to degrade or recycle, leading to a waste of raw materials and aggravating environmental pollution. Herein, a new class of pH-responsive and recyclable hydrogels with versatile gas-releasing and scavenging properties is reported, utilizing pH changes to reversibly control disassembly and reassembly of the hydrogel network. The initial hydrogels are constructed via the one-pot radical polymerization and contain dynamic molecular networks based on hydrophobic interactions, which can disassemble when the materials are placed in low pH solutions. The disassembled copolymer chains can reform hydrogels, following supplementation with fresh mineral salts and micelle monomers in neutral solutions. Moreover, the mineral salts used to reform hydrogels can function as gas donors or scavengers, endowing these hydrogels with versatile gas-releasing and consuming properties. Overall, this research provides a facile and environmentally friendly method to recycle hydrogels with gas-releasing and gas-scavenging properties, which have potential applications in diverse fields, including wound healing, wastewater management, and gas therapy for diseases.


Assuntos
Hidrogéis , Sais , Hidrogéis/química , Polímeros/química , Concentração de Íons de Hidrogênio , Minerais
12.
Mol Ther Methods Clin Dev ; 26: 52-60, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-35755945

RESUMO

Clade F adeno-associated virus (AAV) 9 has been utilized as therapeutic gene delivery vector, and it is capable of crossing blood brain barrier (BBB). Recently, an AAV9-based engineering serotype AAVPHP.eB with enhanced BBB crossing ability further expanded clade F AAVs' usages in the murine central nervous system (CNS) gene delivery. In this study, we determined the cryo-electron microscopy (cryo-EM) structures of the AAVPHP.eB and its parental serotype AAV9 in native form or in complex with their essential receptor AAV receptor (AAVR). These structures reveal the molecular details of their AAVR recognition, where the polycystic kidney disease repeat domain 2 (PKD2) of AAVR interacts with AAV9 and AAVPHP.eB virions at the 3-fold protrusions and the raised capsid regions between the 2- and 5-fold axes, termed the 2/5-fold wall. The interacting patterns of AAVR to AAV9 and AAVPHP.eB are similar to what was observed in AAV1/AAV2-AAVR complexes. Moreover, we found that the AAVPHP.eB variable region VIII (VR-VIII) may independently facilitate the new receptor recognition responsible for enhanced CNS transduction. Our study provides insights into the recognition principles of multiple receptors for engineered AAVPHP.eB and parental serotype AAV9, and further reveal the potential molecular basis underlying their different tropisms.

13.
J Pharm Biomed Anal ; 197: 113946, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33611089

RESUMO

Cetrorelix, a potent third generation of luteinizing hormone releasing hormone (LHRH) antagonist, is a synthetic decapeptide used for treatment of infertility, prostatic hypertrophy and sexual hormone-dependent tumors. The approved drug of cetrorelix (Cetrotide, Asta Medica AG, Frankfurt, Germany.), was used for prevention of premature ovulation in patients undergoing a controlled ovarian stimulation (COS), followed by oocyte pick-up and assisted reproductive techniques, and has been shown safe and effective in controlled ovarian stimulation. Nevertheless, the study of aggregation products of cetrorelix was rarely reported. A simple liquid chromatography mass spectrometry (LC-MS/MS) method was developed for separation, identification and characterization of a new cetrorelix methylene dimer impurity in cetrorelix. The chromatographic separation was achieved on an XSelect Peptide CSH ™C18 column (150 × 4.6 mm, 3.5 µm particle size) using gradient elution with a mobile phase of ammonium formate buffer (pH 3.0, 20 mM), acetonitrile at a flow rate 1.0 mL min-1, and an ultraviolet detection wavelength of 226 nm. The new cetrorelix methylene dimer impurity was characterized by LC-MS/MS and it characteristic fragment ions were summarized. A simple, fast and accurate method was established for the determination of the molecular weight and structure of the new cetrorelix methylene dimer impurity. In this study, the results showed that the cetrorelix was highly unstable in formaldehyde conditions. In addition, it is proposed that the impact of formaldehyde in the environment on the quality of cetrorelix acetate for Injection should be evaluated during the production process.


Assuntos
Hormônio Liberador de Gonadotropina , Espectrometria de Massas em Tandem , Cromatografia Líquida , Feminino , Alemanha , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos
14.
Cell Rep ; 29(10): 3200-3211.e4, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801083

RESUMO

Uveal melanoma (UM), the most common ocular malignancy, is characterized by GNAQ/11 mutations. Hippo/YAP and Ras/mitogen-activated protein kinase (MAPK) emerge as two important signaling pathways downstream of G protein alpha subunits of the Q class (GαQ/11)-mediated transformation, although whether and how they contribute to UM genesis in vivo remain unclear. Here, we adapt an adeno-associated virus (AAV)-based ocular injection method to directly deliver Cre recombinase into the mouse uveal tract and demonstrate that Lats1/2 kinases suppress UM formation specifically in uveal melanocytes. We find that genetic activation of YAP, but not Kras, is sufficient to initiate UM. We show that YAP/TAZ activation induced by Lats1/2 deletion cooperates with Kras to promote UM progression via downstream transcriptional reinforcement. Furthermore, dual inhibition of YAP/TAZ and Ras/MAPK synergizes to suppress oncogenic growth of human UM cells. Our data highlight the functional significance of Lats-YAP/TAZ in UM initiation and progression in vivo and suggest combination inhibition of YAP/TAZ and Ras/MAPK as a new therapeutic strategy for UM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/genética , Melanoma/genética , Melanoma/patologia , Transativadores/genética , Fatores de Transcrição/genética , Neoplasias Uveais/genética , Neoplasias Uveais/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Feminino , Células HEK293 , Humanos , Melanócitos/patologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação/genética , Transdução de Sinais/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
15.
Nat Commun ; 10(1): 3760, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434885

RESUMO

Adeno-associated virus (AAV) receptor (AAVR) is an essential receptor for the entry of multiple AAV serotypes with divergent rules; however, the mechanism remains unclear. Here, we determine the structures of the AAV1-AAVR and AAV5-AAVR complexes, revealing the molecular details by which PKD1 recognizes AAV5 and PKD2 is solely engaged with AAV1. PKD2 lies on the plateau region of the AAV1 capsid. However, the AAV5-AAVR interface is strikingly different, in which PKD1 is bound at the opposite side of the spike of the AAV5 capsid than the PKD2-interacting region of AAV1. Residues in strands F/G and the CD loop of PKD1 interact directly with AAV5, whereas residues in strands B/C/E and the BC loop of PKD2 make contact with AAV1. These findings further the understanding of the distinct mechanisms by which AAVR recognizes various AAV serotypes and provide an example of a single receptor engaging multiple viral serotypes with divergent rules.


Assuntos
Capsídeo/metabolismo , Dependovirus/fisiologia , Receptores de Superfície Celular/metabolismo , Internalização do Vírus , Capsídeo/ultraestrutura , Proteínas do Capsídeo/classificação , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Dependovirus/classificação , Dependovirus/genética , Glicosilação , Células HEK293 , Humanos , Processamento de Imagem Assistida por Computador , Ligação Proteica , Conformação Proteica , Receptores de Superfície Celular/ultraestrutura , Sorogrupo , Canais de Cátion TRPP , Transdução Genética
16.
Oncogene ; 37(21): 2837-2849, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29511345

RESUMO

Resistance to the BCR-ABL tyrosine kinase inhibitor (TKI) remains a challenge for curing the disease in chronic myeloid leukemia (CML) patients as leukemia cells may survive through BCR-ABL kinase activity-independent signal pathways. To gain insight into BCR-ABL kinase activity-independent mechanisms, we performed an initial bioinformatics screen and followed by a quantitative PCR screen of genes that were elevated in CML samples. A total of 33 candidate genes were identified to be highly expressed in TKIs resistant patients. Among those genes, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), controlling the limiting step of glycolysis, was found to be strongly associated with TKIs resistance. PFKFB3 knockdown or pharmacological inhibition of its kinase activity markedly enhanced the sensitivity of CML cells to TKIs. Furthermore, pharmacological inhibition of PFKFB3 inhibited CML cells growth and significantly prolonged the survival of both allograft and xenograft CML mice. ChIP-seq data analysis combined with subsequent knockdown experiment showed that the Ets transcription factor PU.1 regulated the elevated expression of PFKFB3 in TKIs-resistant CML cells. Therefore, our results showed that targeting PFKFB3 sensitizes CML cells to TKIs and PFKFB3 may be a potential BCR-ABL kinase activity-independent mechanism in CML.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Fosfofrutoquinase-2/genética , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Animais , Antígenos de Superfície/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Mesilato de Imatinib/administração & dosagem , Mesilato de Imatinib/farmacologia , Células Jurkat , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Int J Mol Sci ; 18(4)2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28353645

RESUMO

The accumulation of lipofuscin in the retinal pigment epithelium (RPE) is dependent on the effectiveness of photoreceptor outer segment material degradation. This study explored the role of autophagy in the fate of RPE lipofuscin degradation. After seven days of feeding with either native or modified rod outer segments, ARPE-19 cells were treated with enhancers or inhibitors of autophagy and the autofluorescence was detected by fluorescence-activated cell sorting. Supplementation with different types of rod outer segments increased lipofuscin-like autofluorescence (LLAF) after the inhibition of autophagy, while the induction of autophagy (e.g., application of rapamycin) decreased LLAF. The effects of autophagy induction were further confirmed by Western blotting, which showed the conversion of LC3-I to LC3-II, and by immunofluorescence microscopy, which detected the lysosomal activity of the autophagy inducers. We also monitored LLAF after the application of several autophagy inhibitors by RNA-interference and confocal microscopy. The results showed that, in general, the inhibition of the autophagy-related proteins resulted in an increase in LLAF when cells were fed with rod outer segments, which further confirms the effect of autophagy in the fate of RPE lipofuscin degradation. These results emphasize the complex role of autophagy in modulating RPE autofluorescence and confirm the possibility of the pharmacological clearance of RPE lipofuscin by small molecules.


Assuntos
Autofagia , Lipofuscina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Linhagem Celular , Fluorescência , Humanos , Lisossomos/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Sirolimo/farmacologia
18.
Nat Commun ; 8: 14152, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-28106060

RESUMO

Haploinsufficiency of the SLC2A1 gene and paucity of its translated product, the glucose transporter-1 (Glut1) protein, disrupt brain function and cause the neurodevelopmental disorder, Glut1 deficiency syndrome (Glut1 DS). There is little to suggest how reduced Glut1 causes cognitive dysfunction and no optimal treatment for Glut1 DS. We used model mice to demonstrate that low Glut1 protein arrests cerebral angiogenesis, resulting in a profound diminution of the brain microvasculature without compromising the blood-brain barrier. Studies to define the temporal requirements for Glut1 reveal that pre-symptomatic, AAV9-mediated repletion of the protein averts brain microvasculature defects and prevents disease, whereas augmenting the protein late, during adulthood, is devoid of benefit. Still, treatment following symptom onset can be effective; Glut1 repletion in early-symptomatic mutants that have experienced sustained periods of low brain glucose nevertheless restores the cerebral microvasculature and ameliorates disease. Timely Glut1 repletion may thus constitute an effective treatment for Glut1 DS.


Assuntos
Encéfalo/irrigação sanguínea , Erros Inatos do Metabolismo dos Carboidratos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Microvasos/metabolismo , Proteínas de Transporte de Monossacarídeos/deficiência , Animais , Barreira Hematoencefálica/crescimento & desenvolvimento , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Erros Inatos do Metabolismo dos Carboidratos/genética , Erros Inatos do Metabolismo dos Carboidratos/fisiopatologia , Feminino , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Humanos , Masculino , Camundongos , Microvasos/anormalidades , Microvasos/crescimento & desenvolvimento , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Neovascularização Fisiológica
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 189-93, 2017 01.
Artigo em Chinês | MEDLINE | ID: mdl-30196585

RESUMO

The modeling and predicting of vegetation Leaf area index (LAI) is an important component of land surface model and assimilation of remote sensing data. The MODIS LAI product (i.e. MOD15A2) is one of the most widely used LAI data sources. However, the time series of MODIS LAI contains some data of low quality. For example, because of the influence of the cloud, aerosol, etc., the MODIS LAI presents the characteristics of the discontinuous in time and space. In fact, the time series of MODIS LAI include both linear and nonlinear components, which cannot be accurately modeled and predicted by either linear method or nonlinear method alone. In this paper, the original LAI time series data were first smoothed with Savitzky-Golay (SG) filtration and linear interpolation; SARIMA, BP neural network and a hybrid method of SARIMA-BP neural network were then used for modeling and predicting MODIS LAI time series. The SARIMA-BP neural network combined both SARIMA and BP neural network, which could model the linear and the nonlinear component of MODIS LAI time series respectively. That is, the final result of SARIMA-BP neural network was the sum of results of the two methods. Experiments showed that the time series of MODIS LAI that were smoothed with the SG filtration and linear interpolation were more smooth than original time series, with a determination coefficient up to 0.981, closer to 1 than that of SARIMA (0.941) and BP neural network (0.884); the correlation coefficient between SARIMA-BP neural network and the observation is 0.991, higher than that of between SARIMA (0.971) or BP neural network (0.942) SARIMA and the observation. Thus, it can be concluded that, the proposed SARIMA-BP neural network method can better adapt to the LAI time series, and it outperforms the SARIMA and BP neural network methods.


Assuntos
Redes Neurais de Computação , Aerossóis , Folhas de Planta
20.
Vet Immunol Immunopathol ; 170: 13-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26872626

RESUMO

Ficolins are a group of oligomeric defense proteins assembled from collagen-like stalks and fibrinogen-like domains that have common biochemical specificity for N-acetyl-d-glucose amine (GlcNAc) and can function as opsonins. In this report, GlcNAc-binding protein (GBP) purified from porcine nonimmune serum was biochemically characterized as ficolin-α. Ficolin-α was used as an immunogen to generate both rabbit polyclonal and murine monoclonal anti-ficolin-α antibodies, which are not yet commercially available. GBPs have been shown to be present in many animals, including humans; however, their functions are largely unknown. GBPs from chicken, dog, horse, bovine, and human sera were isolated using various chromatography methods. Interestingly, anti-ficolin-α antibody showed cross-reaction with those animal sera GBPs. Furthermore, anti-ficolin-α antibody was reactive with the GlcNAc eluate of Escherichia coli O26-bound and Salmonella-bound porcine serum proteins. Functionally, GBPs and bacteria-reactive pig serum proteins were able to bind with pathogen-associated molecular patterns such as lipopolysaccharides and lipoteichoic acids. Our studies demonstrate that ficolin-α specific antibody was reactive with GBPs from many species as well as bacteria-reactive serum proteins. These proteins may play important roles in innate immunity by sensing danger components that can lead to antibacterial activity.


Assuntos
Acetilglucosamina/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos/imunologia , Lectinas/imunologia , Animais , Proteínas de Bactérias/metabolismo , Bovinos , Galinhas , Reações Cruzadas , Cães , Escherichia coli/metabolismo , Cavalos , Humanos , Lectinas/isolamento & purificação , Lipopolissacarídeos/metabolismo , Ligação Proteica , Coelhos , Salmonella typhimurium/metabolismo , Especificidade da Espécie , Suínos , Ácidos Teicoicos/metabolismo , Ficolinas
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