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1.
EMBO Rep ; 24(2): e54313, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36524339

RESUMO

Somatosensory neurons are highly heterogeneous with distinct types of neural cells responding to specific stimuli. However, the distribution and roles of cell-type-specific long intergenic noncoding RNAs (lincRNAs) in somatosensory neurons remain largely unexplored. Here, by utilizing droplet-based single-cell RNA-seq (scRNA-seq) and full-length Smart-seq2, we show that lincRNAs, but not coding mRNAs, are enriched in specific types of mouse somatosensory neurons. Profiling of lincRNAs from single neurons located in dorsal root ganglia (DRG) identifies 200 lincRNAs localized in specific types or subtypes of somatosensory neurons. Among them, the conserved cell-type-specific lincRNA CLAP associates with pruritus and is abundantly expressed in somatostatin (SST)-positive neurons. CLAP knockdown reduces histamine-induced Ca2+ influx in cultured SST-positive neurons and in vivo reduces histamine-induced scratching in mice. In vivo knockdown of CLAP also decreases the expression of neuron-type-specific and itch-related genes in somatosensory neurons, and this partially depends on the RNA binding protein MSI2. Our data reveal a cell-type-specific landscape of lincRNAs and a function for CLAP in somatosensory neurons in sensory transmission.


Assuntos
Prurido , RNA Longo não Codificante , Células Receptoras Sensoriais , Animais , Camundongos , Histamina , Prurido/genética , RNA Longo não Codificante/genética , Sensação
2.
Environ Res ; 259: 119517, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964585

RESUMO

This paper aims to develop a flow-through electrochemical system with a series of graphene nanoparticles loaded PbO2 reactive electrochemical membrane electrodes (GNPs-PbO2 REMs) on porous Ti substrates with pore sizes of 100, 150, 300 and 600 µm, and apply them to treat antibiotic wastewater. Among them, the GNPs-PbO2 with Ti substrate of 150 µm (Ti-150/GNPs-PbO2) had superior electrochemical degradation performance over the REMs with other pore sizes due to its smaller crystal size, larger electrochemical active specific area, lower charge-transfer impedance and larger oxygen evolution potential. Under the relatively optimized conditions of initial pH of 5, current density of 15 mA cm-2, and membrane flux of 4.20 m3 (m2·h)-1, the Ti-150/GNPs-PbO2 REM realized 99.34% of benzylpenicillin sodium (PNG) removal with an EE/O of 6.52 kWh m-3. Its excellent performance could be explained as the increased mass transfer. Then three plausible PNG degradation pathways in the flow-through electrochemical system were proposed, and great stability and safety of Ti-150/GNPs-PbO2 REM were demonstrated. Moreover, a single-pass Ti-150/GNPs-PbO2 REM system with five-modules in series was designed, which could consistently treat real antibiotic wastewater in compliance with disposal requirements of China. Thus, this study evidenced that the flow-through electrochemical system with the Ti-150/GNPs-PbO2 REM is an efficient alternative for treating antibiotic wastewater.

3.
J Nanobiotechnology ; 22(1): 55, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331774

RESUMO

BACKGROUND: Exosomes are nanoscale extracellular vesicles (30-160 nm) with endosome origin secreted by almost all types of cells, which are considered to be messengers of intercellular communication. Cancerous exosomes serve as a rich source of biomarkers for monitoring changes in cancer-related physiological status, because they carry a large number of biological macromolecules derived from parental tumors. The ultrasensitive quantification of trace amounts of cancerous exosomes is highly valuable for non-invasive early cancer diagnosis, yet it remains challenging. Herein, we developed an aptamer-carrying tetrahedral DNA (Apt-TDNA) microelectrode sensor, assisted by a polydopamine (PDA) coating with semiconducting properties, for the ultrasensitive electrochemical detection of cancer-derived exosomes. RESULTS: The stable rigid structure and orientation of Apt-TDNA ensured efficient capture of suspended exosomes. Without PDA coating signal amplification strategy, the sensor has a linear working range of 102-107 particles mL-1, with LOD of ~ 69 exosomes and ~ 42 exosomes for EIS and DPV, respectively. With PDA coating, the electrochemical signal of the microelectrode is further amplified, achieving single particle level sensitivity (~ 14 exosomes by EIS and ~ 6 exosomes by DPV). CONCLUSIONS: The proposed PDA-assisted Apt-TDNA microelectrode sensor, which integrates efficient exosome capture, sensitive electrochemical signal feedback with PDA coating signal amplification, provides a new avenue for the development of simple and sensitive electrochemical sensing techniques in non-invasive cancer diagnosis and monitoring treatment response.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exossomos , Indóis , Neoplasias , Polímeros , Humanos , Microeletrodos , Exossomos/química , DNA/análise , Neoplasias/diagnóstico , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de Detecção
4.
Pharm Dev Technol ; 28(2): 232-239, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36789978

RESUMO

The colonic delivery system of toxin neutralizing antibody is a promising method for treating Clostridium difficile infection (CDI) and has some advantages over the parental administration of a neutralizing antibody. However, colonic delivery of biologics presents several challenges, including instability of biologics during encapsulation into the delivery system and harsh conditions in the upper GI tract. In this work, we described a multi-particulate delivery system encapsulating a tetra-valent antibody ABAB-IgG1 with the potential to treat CDI. This work first approved that the cecum injection of ABAB-IgG1 into the lower GI tract of mice could relieve the symptoms, enhance the clinical score, and improve the survival rate of mice during CDI. Then, the antibody was spray layered onto mannitol beads and then enteric coated with pH-sensitive polymers to achieve colon-targeting release. The in vitro release of antibody from the multi-particulate system and the pH-sensitive release of antibody was monitored. The in vivo efficacy of this system was further examined and confirmed in mice and hamsters. In summary, the findings of this study should provide practical information and potential treatment options for CDI through colonic delivery of antibody therapeutics to the lower GI tract using a multi-particulate delivery system.


Assuntos
Anticorpos Neutralizantes , Infecções por Clostridium , Cricetinae , Camundongos , Animais , Anticorpos Neutralizantes/uso terapêutico , Imunoglobulina G , Colo , Infecções por Clostridium/tratamento farmacológico , Trato Gastrointestinal
5.
Toxicol Mech Methods ; 33(1): 47-55, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35592903

RESUMO

Hepatocellular carcinoma (HCC) constitutes a major global health threat due to the high incidence and mortality. Sorafenib is known as the first-line medication for advanced HCC; however, it only extends the limited benefit for HCC patients as the development of acquired resistance. Withaferin A exerts broad pharmaceutical applications in several cancers. However, its effects on HCC cell metastatic potential and sorafenib resistance remain elusive. Here, we corroborated that Withaferin A greatly restrained cell viability, invasion, vasculogenic mimicry (VM) formation, and VE-cadherin levels in HepG2 and SNU449 cells. Moreover, Withaferin A sensitized sorafenib (SR)-resistant HCC cells to sorafenib. In striking contrast to the parental cells, lower ferroptosis was observed in SR-resistant cells as the lower ROS, MDA, and higher intracellular GSH levels in SR-resistant cells. Of interest, Withaferin A enhanced ferroptosis in SR-resistant cells, which was reversed by ferroptosis antagonist liproxstation-1. Notably, Withaferin A elevated Keap1 expression to mitigate Nrf2 signaling activation-mediated epithelial to mesenchymal transition (EMT) and ferroptosis-related protein xCT expression. Importantly, blockage of the Keap1/Nrf2 signaling overturned Withaferin A-evoked ferroptosis and facilitated sorafenib resistance. In addition, knockdown of Keap1 antagonized the inhibitory efficacy of Withaferin A on HCC cell viability, invasion, and VM formation. Consequently, Withaferin A may attenuate the metastatic potential and sorafenib resistance by regulating Keap1/Nrf2-associated EMT and ferroptosis. Thus, Withaferin A may serve as a promising agent for HCC therapy, especially for advanced HCC.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Neoplasias Hepáticas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Resistência a Medicamentos , Resistencia a Medicamentos Antineoplásicos
6.
BMC Genomics ; 23(1): 246, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35354401

RESUMO

BACKGROUND: Apple Glomerella leaf spot (GLS) and apple bitter rot (ABR) are two devastating foliar and fruit diseases on apples. The different symptoms of GLS and ABR could be related to different transcriptome patterns. Thus, the objectives of this study were to compare the transcriptome profiles of Colletotrichum gloeosporioides species complex isolates GC20190701, FL180903, and FL180906, the pathogen of GLS and ABR, and to evaluate the involvement of the genes on pathogenicity. RESULTS: A relatively large difference was discovered between the GLS-isolate GC20190701 and ABR-isolates FL180903, FL180906, and quite many differential expression genes associated with pathogenicity were revealed. The DEGs between the GLS- and ABR-isolate were significantly enriched in GO terms of secondary metabolites, however, the categories of degradation of various cell wall components did not. Many genes associated with secondary metabolism were revealed. A total of 17 Cytochrome P450s (CYP), 11 of which were up-regulated while six were down-regulated, and five up-regulated methyltransferase genes were discovered. The genes associated with the secretion of extracellular enzymes and melanin accumulation were up-regulated. Four genes associated with the degradation of the host cell wall, three genes involved in the degradation of cellulose, and one gene involved in the degradation of xylan were revealed and all up-regulated. In addition, genes involved in melanin syntheses, such as tyrosinase and glucosyltransferase, were highly up-regulated. CONCLUSIONS: The penetration ability, pathogenicity of GLS-isolate was greater than that of ABR-isolate, which might indicate that GLS-isolate originated from ABR-isolates by mutation. These results contributed to highlighting the importance to investigate such DEGs between GLS- and ABR-isolate in depth.


Assuntos
Colletotrichum , Malus , Animais , Colletotrichum/genética , Perfilação da Expressão Gênica , Malus/genética , Phyllachorales/genética , Transcriptoma
7.
Cytokine ; 156: 155925, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35660714

RESUMO

Gasdermin E (GSDME) is a member of the gasdermin family. Cleavage of mammalian GSDME by apoptotic caspases or granzyme proteases liberates the N-terminal effector domain (GSDME-N), which is capable of forming membrane pores and executing inflammation and cell death. Herein, duck GSDME was first cloned with a total length of 1500 bp and encoding 499 amino acids (aa), which is most evolutionally related to the chicken GSDME. The tissue-distribution profiles of GSDME showed that relatively high levels of GSDME mRNA were detected in immune tissues of duckling and adult ducks. Additionally, GSDME mRNA was significantly upregulated in duck primary embryo fibroblasts (DEFs) and duck primary ovary cells after duck Tembusu virus (DTMUV) infection. Intriguingly, when duck caspase-3 was coexpressed, the duck GSDME produced two GSDME-N fragments with molecular weights of 25 kDa and 30 kDa. Furthermore, both GSDME and cleaved GSDME were observed to be located in the cytoplasm by indirect immunofluorescence assay (IFA). Taken together, our research data show that duck GSDME has similar biological characteristics to mammals. These findings highlight the role of duck GSDME in TMUV infection, indicating that cooperation between GSDME and caspase-3 promotes the proteolytic process.


Assuntos
Patos , Mamíferos , Animais , Caspase 3/genética , Caspase 3/metabolismo , Feminino , Flavivirus , Mamíferos/genética , Mamíferos/metabolismo , Proteólise , RNA Mensageiro/metabolismo , Distribuição Tecidual
8.
BMC Nephrol ; 23(1): 231, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764943

RESUMO

BACKGROUND: The association between serum total indoxyl sulfate (tIS), and cardiovascular disease (CVD) and all-cause mortality is a matter of debate. In the current study we sought to determine the association, if any, between serum tIS, and all-cause and CVD-associated mortality in patients on maintenance hemodialysis (MHD). METHODS: A prospective cohort study was conducted involving 500 MHD patients at Dalian Municipal Central Hospital from 31 December 2014 to 31 December 2020. Serum tIS levels were measured at baseline and classified as high (≥44.16 ng/ml) or low (< 44.16 ng/ml) according to the "X-tile" program. Besides, the associations between continuous serum tIS and outcomes were also explored. Predictors were tested for colinearity using variance inflation factor analysis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models. Restricted cubic spline model was performed to assess dose-response relationships between tIS concentration and all-cause and CVD mortality. RESULTS: During a 58-month median follow-up period, 224 deaths (132 CVD deaths) were documented. After adjustment for potential confounders, the serum tIS level was positively associated with all-cause mortality (HR = 1.02, 95% = 1.01-1.03); however, we did not detect a significant association when tIS was a dichotomous variable. Compared with the MHD population with a serum tIS level < 44.16 ng/ml, the adjusted HR for CVD mortality among those with a serum tIS level ≥ 44.16 ng/ml was 1.76 (95% = 1.10-2.82). Furthermore, we also noted the same association when the serum tIS level was a continuous variable. CONCLUSION: The serum tIS level was associated with higher risk of all-cause and CVD mortality among MHD patients. Further prospective large-scale studies are required to confirm this finding.


Assuntos
Doenças Cardiovasculares , Indicã , Humanos , Modelos de Riscos Proporcionais , Estudos Prospectivos , Diálise Renal
9.
BMC Pediatr ; 22(1): 465, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35918695

RESUMO

BACKGROUND: Milk fat globule membrane (MFGM), natural to breast milk, is essential for neonatal development, but lacking from standard infant formulas. OBJECTIVES: To evaluate the safety and tolerability of MFGM supplementation in formula for infants 0 to 12 months. METHODS: In a prospective, multicentre, double-blind, randomized trial, healthy term infants were randomized to a standard formula (SF, n = 104) or an MFGM-enriched formula (MF, n = 108) for 6 months and a corresponding follow-on formula until 12 months. Exclusively breast-fed infants (n = 206) were recruited as the reference group (BFR). Tolerance and safety events were recorded continuously. Anthropometric measurements were assessed at enrolment, 42 days and 4, 6, 8 and 12 months. RESULTS: Infants (n = 375) completed the study with average dropout of < 20%. Stool frequency, color, and consistency between SF and MF were not significantly different throughout, except the incidence of loose stools in MF at 6 months being lower than for SF (odds ratio 0.216, P < 0.05) and the frequency of green-colored stools at 12 months being higher in MF (CI 95%, odds ratio 8.92, P < 0.05). The BFR had a higher frequency of golden stools and lower rate of green stools (4-6 months) than the two formula-fed groups (P < 0.05). SF displayed more diarrhoea (4.8%) than MF (1%) and BFR (1%) at the 8-month visit (P < 0.05). BFR (0-1%) had significantly less (P < 0.05) lower respiratory infections than MF (4.6-6.5%) and SF (2.9-5.8%) at 6- and 8-months, respectively. Formula intake, frequency of spit-up/vomiting or poor sleep were similar between SF and MF. Growth rate (g/day) was similar at 4, 6, 8 and 12 months between the 3 groups, but growth rate for BFR was significantly higher than for SF and MF at 42 days (95% CI, P = 0.001). CONCLUSIONS: MFGM-enriched formula was safe and well-tolerated in healthy term infants between 0 and 12 months, and total incidences of adverse events were similar to that for the SF group. A few differences in formula tolerance were observed, however these differences were not in any way related to poor growth.


Assuntos
Glicolipídeos , Fórmulas Infantis , Aleitamento Materno , China , Método Duplo-Cego , Feminino , Glicoproteínas , Humanos , Lactente , Recém-Nascido , Gotículas Lipídicas , Leite Humano , Estudos Prospectivos
10.
Sensors (Basel) ; 22(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080779

RESUMO

Intelligent monitoring and early warning of rock mass failure is vital. To realize the early intelligent identification of dynamic fractures in the failure process of complex fractured rocks, 3D printing of the fracture network model was used to produce rock-like specimens containing 20 random joints. An algorithm for the early intelligent identification of dynamic fractures was proposed based on the YOLOv5 deep learning network model and DIC cloud. The results demonstrate an important relationship between the overall strength of the specimen with complex fractures and dynamic fracture propagation, and the overall specimen strength can be judged semi-quantitatively by counting dynamic fracture propagation. Before the initiation of each primary fracture, a strain concentration area appears, which indicates new fracture initiation. The dynamic evolution of primary fractures can be divided into four types: primary fractures, stress concentration areas, new fractures, and cross fractures. The cross fractures have the greatest impact on the overall strength of the specimen. The overall identification accuracy of the four types of fractures identified by the algorithm reached 88%, which shows that the method is fast, accurate, and effective for fracture identification and location, and classification of complex fractured rock masses.


Assuntos
Fraturas Ósseas , Algoritmos , Humanos
11.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32075929

RESUMO

Duck Tembusu virus (DTMUV), which is similar to other mosquito-borne flaviviruses that replicate well in most mammalian cells, is an emerging pathogenic flavivirus that has caused epidemics in egg-laying and breeding waterfowl. Immune organ defects and neurological dysfunction are the main clinical symptoms of DTMUV infection. Preinfection with DTMUV makes the virus impervious to later interferon (IFN) treatment, revealing that DTMUV has evolved some strategies to defend against host IFN-dependent antiviral responses. Immune inhibition was further confirmed by screening for DTMUV-encoded proteins, which suggested that NS2A significantly inhibited IFN-ß and IFN-stimulated response element (ISRE) promoter activity in a dose-dependent manner and facilitated reinfection with duck plague virus (DPV). DTMUV NS2A was able to inhibit duck retinoic acid-inducible gene-I (RIG-I)-, and melanoma differentiation-associated gene 5 (MDA5)-, mitochondrial-localized adaptor molecules (MAVS)-, stimulator of interferon genes (STING)-, and TANK-binding kinase 1 (TBK1)-induced IFN-ß transcription, but not duck TBK1- and interferon regulatory factor 7 (IRF7)-mediated effective phases of IFN response. Furthermore, we found that NS2A competed with duTBK1 in binding to duck STING (duSTING), impaired duSTING-duSTING binding, and reduced duTBK1 phosphorylation, leading to the subsequent inhibition of IFN production. Importantly, we first identified that the W164A, Y167A, and S361A mutations in duSTING significantly impaired the NS2A-duSTING interaction, which is important for NS2A-induced IFN-ß inhibition. Hence, our data demonstrated that DTMUV NS2A disrupts duSTING-dependent antiviral cellular defenses by binding with duSTING, which provides a novel mechanism by which DTMUV subverts host innate immune responses. The potential interaction sites between NS2A and duSTING may be the targets of future novel antiviral therapies and vaccine development.IMPORTANCE Flavivirus infections are transmitted through mosquitos or ticks and lead to significant morbidity and mortality worldwide with a spectrum of manifestations. Infection with an emerging flavivirus, DTMUV, manifests with clinical symptoms that include lesions of the immune organs and neurological dysfunction, leading to heavy egg drop and causing serious harm to the duck industry in China, Thailand, Malaysia, and other Southeast Asian countries. Mosquito cells, bird cells, and mammalian cell lines are all susceptible to DTMUV infection. An in vivo study revealed that BALB/c mice and Kunming mice were susceptible to DTMUV after intracerebral inoculation. Moreover, there are no reports about DTMUV-related human disease, but antibodies against DTMUV and viral RNA were detected in serum samples of duck industry workers. This information implies that DTMUV has expanded its host range and may pose a threat to mammalian health. However, the pathogenesis of DTMUV is largely unclear. Our results show that NS2A strongly blocks the STING-induced signal transduction cascade by binding with STING, which subsequently blocks STING-STING binding and TBK1 phosphorylation. More importantly, the W164, Y167, or S361 residues in duSTING were identified as important interaction sites between STING and NS2A that are vital for NS2A-induced IFN production and effective phases of IFN response. Uncovering the mechanism by which DTMUV NS2A inhibits IFN in the cells of its natural hosts, ducks, will help us understand the role of NS2A in DTMUV pathogenicity.


Assuntos
Flavivirus/metabolismo , Interferon beta/metabolismo , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Patos/virologia , Flavivirus/patogenicidade , Infecções por Flavivirus/virologia , Humanos , Imunidade Inata/imunologia , Fator Regulador 7 de Interferon , Interferons/metabolismo , Proteínas de Membrana , Proteínas Serina-Treonina Quinases , Transdução de Sinais/imunologia , Proteínas não Estruturais Virais/metabolismo
12.
J Org Chem ; 86(21): 14627-14639, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34658240

RESUMO

Herein, a metal-free and solvent-free protocol was developed for the C-N coupling of heteroaryl halides and amines, which afforded numerous heteroaryl amines or their hydrochlorides without any external base. Further investigations elucidated that the basicity of amines and specific interactions derived from the X-ray crystallography analysis of 3j'·HCl played pivotal roles in the reactions. Moreover, this protocol was scalable to gram scales and applicable to drug molecules, which demonstrated its practical value for further applications.


Assuntos
Aminas , Metais , Solventes
13.
Asia Pac J Clin Nutr ; 30(3): 401-414, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34587700

RESUMO

BACKGROUND AND OBJECTIVES: Human milk fat globule membrane (MFGM) has multifunctional health benefits. We evaluated neurodevelopment and growth of healthy term infants fed bovine milk-derived MFGM-enriched formula (MF) over 12 months. METHODS AND STUDY DESIGN: A prospective, multi-center, double-blind, randomized trial was conducted in Fuzhou, China. Healthy term infants (n=212), aged <14 days, were assigned randomly to be fed MF or a standard formula (SF) for 6 months and then switched to stage 2 MF and SF formula until 12 months. A reference group (n=206) contained healthy breastfed infants (BFR). Neurodevelopment was assessed with Bayley-III Scales. RESULTS: At 12 months, the composite social emotional (+3.5) and general adaptive behaviour (+5.62) scores were significantly higher in MF than SF (95% CIs 0.03 to 6.79 and 1.78 to 9.38; p=0.048 and 0.004, respectively). Mean cognitive (+2.86, 95% CIs -1.10 to 6.80, p=0.08), language (+0.39, 95% CIs -2.53 to 3.30, p=0.87) and motor (+0.90, 95% CIs -2.32 to 4.13, p=0.49) scores tended to be higher in MF than SF, but the differences between the two groups were not significant. BFR scored higher on Bayley-III than either MF or SF at 6 and 12 months. Cognitive scores were significantly higher in BFR than SF (95% CI 0.05 to 7.20; p=0.045), but not MF (p=0.74) at 6 months. Short-term memory was significantly higher in MF than SF at 12 months (95% CI 1.40 to 12.33; p=0.002). At 4 months, serum gangliosides were significantly higher in MF and BFR than SF (95% CI 0.64 to 13.02; p=0.025). Milk intake, linear growth, body mass and head circumference were not significantly different between formula-fed groups. CONCLUSIONS: MFGM supplementation in early life supports adequate growth, increased serum gangliosides concentration and improves some measures of cognitive development in Chinese infants.


Assuntos
Fórmulas Infantis , Idioma , China , Feminino , Glicolipídeos , Glicoproteínas , Humanos , Lactente , Gotículas Lipídicas , Leite Humano , Estudos Prospectivos
14.
Mol Pharm ; 16(8): 3687-3693, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31306023

RESUMO

Thermal stability is essential for the understanding of protein stability and is a critical quality attribute of therapeutic biologics, including enzymes, fusion proteins, monoclonal antibodies, etc. The commonly used analytical methods, such as differential scanning calorimetry (DSC), differential scanning fluorimetry (DSF), and circular dichroism (CD), have their limitations in measuring protein thermal stability. Through this work, we described a novel method to probe the thermal stability of proteins in various formulations using a temperature scanning viscometer. The viscosity of the material was plotted against the temperature, and the peak in the first derivative of the viscosity versus temperature was shown to be related to the protein melting temperature. The measured melting temperature of bovine serum albumin (BSA) at a concentration of 1 mg/mL in phosphate buffer was 63 °C, which was close to the value of 64 °C obtained by DSC. The unfolding of BSA was confirmed using orthogonal techniques of second derivative ultraviolet-visible (UV-vis) spectroscopy and dynamic light scattering (DLS). This method was also able to reveal the microenvironment changes of proteins, including formulation effects. Other multiple domains proteins including lysozyme and IgG were also tested using this method and showed comparable melting temperatures with DSC. This work showed the feasibility of using a temperature scanning viscometer to measure the thermal stability of proteins in diverse formulation matrices with wider protein concentration ranges.


Assuntos
Química Farmacêutica/instrumentação , Reologia/instrumentação , Anticorpos Monoclonais/química , Produtos Biológicos/química , Química Farmacêutica/métodos , Difusão Dinâmica da Luz , Estudos de Viabilidade , Desnaturação Proteica , Estabilidade Proteica , Reologia/métodos , Soroalbumina Bovina/química , Temperatura , Viscosidade
15.
Mol Pharm ; 16(3): 1119-1131, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30698973

RESUMO

Oral administration is advantageous compared to the commonly used parenteral administration for local therapeutic uses of biologics or mucosal vaccines, since it can specifically target the gastrointestinal (GI) tract. It offers better patient compliance, even though the general use of such a delivery route is often limited by potential drug degradation in the GI tract and poor absorption. Using bovine serum albumin (BSA) and lysozyme as two model proteins, we studied their solid-state properties, mechanical properties, and tabletability as well as effects of compaction pressure, particle size, and humidity on protein degradation. It was found that BSA and lysozyme are highly hygroscopic, and their tablet manufacturability (powder caking, punch sticking, and tablet lamination) is sensitive to the humidity. BSA and lysozyme exhibited high plasticity and excellent tabletability and remained amorphous at high pressure and humidity. As for protein stability, lysozyme was resistant to high pressure (up to 300 MPa) and high humidity (up to 93%). In contrast, BSA underwent aggregation upon compression, an effect that was more pronounced for smaller BSA particles. High humidity accelerated the aggregation of BSA during incubation, but it did not further synergize with mechanical stress to induce protein degradation. Thus, compression can potentially induce protein aggregation, but this effect is protein-dependent. Therefore, strategies (e.g., the use of excipients, optimized manufacturing processes) to inhibit protein degradation should be explored before their tablet dosage form development.


Assuntos
Produtos Biológicos , Composição de Medicamentos/métodos , Excipientes/química , Muramidase/química , Pressão , Soroalbumina Bovina/química , Comprimidos/química , Animais , Sítios de Ligação , Bovinos , Estabilidade Enzimática , Umidade , Tamanho da Partícula , Pós/química , Agregados Proteicos , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Desdobramento de Proteína , Proteólise , Temperatura
17.
Carcinogenesis ; 39(3): 471-481, 2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29361151

RESUMO

Freeze-dried black raspberry (BRB) powder is considered as a potential cancer chemopreventive agent. In this study, we fed azoxymethane (AOM)/dextran sodium sulfate (DSS)-treated C57BL/6J mice with a diet containing BRB anthocyanins for 12 weeks, and this led to a reduction in colon carcinogenesis. These animals had consistently lower tumor multiplicity compared with AOM/DSS-treated mice not receiving BRB anthocyanins. In AOM/DSS-treated mice, the number of pathogenic bacteria, including Desulfovibrio sp. and Enterococcus spp., was increased significantly, whereas probiotics such as Eubacterium rectale, Faecalibacterium prausnitzii and Lactobacillus were dramatically decreased, but BRB anthocyanins supplement could reverse this imbalance in gut microbiota. BRB anthocyanins also caused the demethylation of the SFRP2 gene promoter, resulting in increased expression of SFRP2, both at the mRNA and protein levels. Furthermore, the expression levels of DNMT31 and DNMT3B, as well as of p-STAT3 were downregulated by BRB anthocyanins in these animals. Taken together, these results suggested that BRB anthocyanins could modulate the composition of gut commensal microbiota, and changes in inflammation and the methylation status of the SFRP2 gene may play a central role in the chemoprevention of CRC.


Assuntos
Antocianinas/farmacologia , Neoplasias Colorretais , Microbioma Gastrointestinal/efeitos dos fármacos , Proteínas de Membrana/genética , Rubus , Animais , Azoximetano/toxicidade , Quimioprevenção , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Metilação de DNA/efeitos dos fármacos , Desmetilação/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Compostos Fitoquímicos/farmacologia
19.
PLoS Biol ; 13(9): e1002243, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26356530

RESUMO

Phosphoglycerate kinase 1 (PGK1) catalyzes the reversible transfer of a phosphoryl group from 1, 3-bisphosphoglycerate (1, 3-BPG) to ADP, producing 3-phosphoglycerate (3-PG) and ATP. PGK1 plays a key role in coordinating glycolytic energy production with one-carbon metabolism, serine biosynthesis, and cellular redox regulation. Here, we report that PGK1 is acetylated at lysine 220 (K220), which inhibits PGK1 activity by disrupting the binding with its substrate, ADP. We have identified KAT9 and HDAC3 as the potential acetyltransferase and deacetylase, respectively, for PGK1. Insulin promotes K220 deacetylation to stimulate PGK1 activity. We show that the PI3K/AKT/mTOR pathway regulates HDAC3 S424 phosphorylation, which promotes HDAC3-PGK1 interaction and PGK1 K220 deacetylation. Our study uncovers a previously unknown mechanism for the insulin and mTOR pathway in regulation of glycolytic ATP production and cellular redox potential via HDAC3-mediated PGK1 deacetylation.


Assuntos
Fosfoglicerato Quinase/metabolismo , Acetilação , Difosfato de Adenosina/metabolismo , Animais , Metabolismo dos Carboidratos , Ativação Enzimática , Glicólise , Células HEK293 , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Humanos , Masculino , Camundongos Endogâmicos BALB C , Proteínas do Tecido Nervoso/metabolismo , Oxirredução , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
20.
Opt Express ; 25(7): 7349-7357, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28380858

RESUMO

An optical-resolution photoacoustic microscope (OR-PAM) with capability of fast axial-scanning was developed by using a tunable acoustic gradient (TAG) lens. The TAG lens was designed to continuously changing the focal plane of OR-PAM by modulating its refractive power with fast-changing ultrasonic standing wave. The performance was shown by imaging a carbon fiber. We achieved a DoF of about 750 µm. The head of a zebrafish was also imaged to further demonstrate the feasibility of our method.

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