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1.
Ecotoxicol Environ Saf ; 232: 113250, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121259

RESUMO

The sea temperature has been observed to chronically increase during the past decades, leaving unpredictable influences to the marine biological resources. Thus, it is of vital significance to study the biological responses of ocean inhabited organisms with the artificially stimulated heat stress environment. Cynoglossus semilaevis provides us with an ideal model to study the influence of chronic heat stress on the sexual differentiation in marine teleosts for its genetic sex determination (GSD) + environmental effected (EE) sex determination system. In this study, the comparative experiment was conducted employing heated seawater (HT group) and ambient seawater (CT group) to cultivate juvenile C. semilaevis respectively. Significant differences were exhibited in growth performance and a delayed germ cell development effect was found in pseudomales formed under chronic heat stress. Using transcriptome analysis, the transcription profile of 55 days post fertilization (dpf) and 100 dpf juveniles' gonads were studied. A total of 47 libraries were constructed with an average mapping rate of 94.63% after assembling. GO and KEGG enrichment were proceeded using DEGs screened out between (1) pseudomale gonads at 55 dpf and 100 dpf in HT and CT group (2) pseudomale and female gonads at 55 dpf and 100 dpf in HT and CT group. Terms and pathways involved in steroid stimulation, reproduction ability, germ cell proliferation et al. were shed light on. The expression pattern of 29 DEGs including amh, hsp90b1, pgr et al. were also provided to supplement the results of functional enrichment. Weighted gene co-expression networks analysis (WGCNA) was constructed and hspb8-like, histone H2A.V were exhibited to play vital roles in the heat-induced masculinization. Our findings facilitate the understanding for transcriptional variations in intensive masculinization cause by chronic heat stress of C. semilaevis and provide referable study of the influences on the teleosts in elevated sea temperature.


Assuntos
Linguados , Linguado , Animais , Feminino , Linguados/genética , Linguados/metabolismo , Perfilação da Expressão Gênica , Gônadas/metabolismo , Resposta ao Choque Térmico/genética
2.
Mol Pharm ; 12(4): 1005-17, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25687223

RESUMO

Screening for pharmaceutically viable stability from measurements of thermally induced protein unfolding and short-term accelerated stress underpins much molecule design, selection, and formulation in the pharmaceutical biotechnology industry. However, the interrelationships among intrinsic protein conformational stability, thermal denaturation, and pharmaceutical stability are complex. There are few publications in which predictions from thermal unfolding-based screening methods are examined together with pharmaceutically relevant long-term storage stability performance. We have studied eight developable therapeutic IgG molecules under solution conditions optimized for large-scale commercial production and delivery. Thermal unfolding profiles were characterized by differential scanning calorimetry (DSC) and intrinsic fluorescence recorded simultaneously with static light scattering (SLS). These molecules exhibit a variety of thermal unfolding profiles under common reference buffer conditions and under individually optimized formulation conditions. Aggregation profiles by SE-HPLC and bioactivity upon long-term storage at 5, 25, and 40 °C establish that IgG molecules possessing a relatively wide range of conformational stabilities and thermal unfolding profiles can be formulated to achieve pharmaceutically stable drug products. Our data suggest that a formulation design strategy that increases the thermal unfolding temperature of the Fab transition may be a better general approach to improving pharmaceutical storage stability than one focused on increasing Tonset or Tm of the first unfolding transition.


Assuntos
Anticorpos Monoclonais/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Humanos , Imunoglobulina G/química , Luz , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Estabilidade Proteica , Espalhamento de Radiação , Espectrometria de Fluorescência , Temperatura
3.
J Neurosci ; 33(6): 2388-97, 2013 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-23392668

RESUMO

In the developing peripheral nervous system, axon-derived signals stimulate Schwann cells to undergo a global genetic reprogramming involving the cessation of cellular division and the upregulation of myelin genes. How such a comprehensive change in gene transcription is regulated is poorly understood. Here we report that BRG1/SMARCA4, the central helicase of the mammalian SWI/SNF-related chromatin remodeling complex, is required for Schwann cells to differentiate and form myelin, both in vitro and in vivo, in the mouse. BRG1 was highly activated in Schwann cells at early stages of myelination, and loss of the enzyme inhibited their differentiation and completely prevented myelin formation. Furthermore, we identify NF-κB as a key transcription factor that associates with the BRG1 complex in response to neuregulin 1 type III. During myelination, BRG1 was activated through the formation of a complex with NF-κB, and both proteins bound to the promoter region of Sox10, an inducer of myelination. These findings delineate a novel mechanism whereby axonal signals promote myelination through the remodeling of chromatin structure.


Assuntos
Diferenciação Celular/fisiologia , Cromatina/metabolismo , DNA Helicases/metabolismo , NF-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Células de Schwann/fisiologia , Fatores de Transcrição/metabolismo , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Cromatina/fisiologia , Técnicas de Cocultura , DNA Helicases/fisiologia , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Camundongos Transgênicos , NF-kappa B/fisiologia , Proteínas Nucleares/fisiologia , Ratos , Células de Schwann/citologia , Fatores de Transcrição/fisiologia
4.
Mar Pollut Bull ; 200: 116074, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290369

RESUMO

Salinity, being an indispensable abiotic factor crucial for the survival of marine organisms, has demonstrated diverse alterations globally in response to the current trend of global warming. In this study, the effect of chronic low salinity stress on teleosts' sex differentiation was investigated using Cynoglossus semilaevis, an economically important fish with both genetic and environmental sex determination system. The cultivation experiment was conducted employing artificially simulated seawater of 20 ppt and ambient sea water of 30 ppt to rear juveniles C. semilaevis. Throughout the experiment, the growth performance was assessed and the histology of gonadal development was examined, a significantly lower masculinization rate was observed in LS group. To gain further insights, transcriptome analysis was conducted using raw reads obtained from 53 libraries derived from gonads of 55 days post fertilization (dpf) and 100 dpf juveniles in both LS and CT groups. GO/KEGG enrichment were further proceeded, Terms and pathways involved in reproduction ability, germ cell proliferation, immune function, steroid metabolism etc., were illuminated and a possible crosstalk between HPI and HPG axis was proposed. WGCNA was conducted and two hub genes, hspb8-like and Histone H2A.V were exhibited to be of great significance in the changes of masculinization rate. Our findings provided solid reference for sex differentiation study of GSD + ESD species in a constantly changing ocean environment, as well as practice guiding significance for the environmental management for the culture of C. semilaevis.


Assuntos
Linguados , Linguado , Animais , Linguados/metabolismo , Perfilação da Expressão Gênica , Gônadas
5.
Medicine (Baltimore) ; 102(47): e36287, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38013316

RESUMO

Rheumatoid arthritis is an autoimmune disease characterized by chronic polyarticular pain, for which no cure currently exists. In Chinese medicine, rheumatoid arthritis (RA) is believed to be caused by phlegm and blood stagnation. Shentong Zhuyu decoction can be used to treat RA, as it promotes blood circulation, resolves blood stasis, and relieves pain. In our study, we used network pharmacology and computer-aided drug design to evaluate the components, active compounds, and targets of Shentong Zhuyu decoction (STZY). Our results suggest that STZY contains active compounds such as quercetin, luteolin, and formononetin that regulate immune network targets. RA associated genes are enriched in pathways including those associated with nuclear factor kappa B, phosphatidylinositol-3-kinase/AKT, and hypoxia inducible factor 1 signaling. The main active compounds in STZY (quercetin and luteolin) were derived from Achyranthis Bidentatae Radix, Carthami Flos, licorice, Cyperi Rhizoma, and Myrrha and targeted the pro-inflammatory cytokines interleukin 2, interleukin 1 alpha, interleukin 1 beta, and interleukin 6. In addition, the compounds quercetin, luteolin, and formononetin in these herbs can target the anti-inflammatory cytokines interleukin 4 and interleukin 10. Our results suggest that STZY can balance the immune network, promote an anti-inflammatory environment, and reduce the clinical symptoms of RA. Based on the close relationship between inflammatory response and osteoclast formation, we hypothesized that STZY may inhibit inflammation and alleviate bone destruction in RA. Our findings indicate that STZY can treat RA through multiple components, targets, and pathways. This study may provide a reference for the clinical application of STZY in RA treatment.


Assuntos
Artrite Reumatoide , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa/métodos , Biologia de Sistemas , Luteolina/uso terapêutico , Quercetina/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Dor/tratamento farmacológico , Desenho de Fármacos
6.
Biotechnol Bioeng ; 108(4): 977-82, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21404269

RESUMO

Monoclonal antibody (mAb) fragmentation can be a widespread problem across the biotechnology industry and there is a current need to better understand the underlying principles. Here, we report an example of a high-purity human IgG1 mAb prepared from CHO cells exhibiting fragmentation that can be attributed to residual proteolytic enzyme activity. The concomitant occurrence of proteolytic and non-proteolytic peptide bond cleavage is shown and the respective fragmentation patterns characterized using high-resolution LC-MS. Fragmentation rates are monitored by SE-HPLC and SDS-PAGE over the pH range 4-6 and characterized in the presence and absence of pepstatin A, an inhibitor of acidic proteases. After 20 days at 40°C, pH 4, ∼60% decrease in BIIB-mAb monomer peak occurred attributed to residual proteolytic activity. At pH 5, this value was ∼13%. These results have implications for formulation design studies and the interpretation of accelerated stability data. A simple method to screen for acidic protease activity using the proteolytic enzyme inhibitor pepstatin A is described.


Assuntos
Anticorpos Monoclonais/metabolismo , Células CHO/enzimologia , Endopeptidases/metabolismo , Imunoglobulina G/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Cricetinae , Cricetulus , Humanos , Imunoglobulina G/isolamento & purificação
7.
Mol Cell Proteomics ; 8(1): 70-85, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18723843

RESUMO

Gastric cancer is the second most common cancer worldwide and has a poor prognosis. To determine the mechanism of adaptation to metabolic stress in cancer cells, we used gastric cancer as a model system to reveal the potential signaling pathways involved. Two-dimensional polyacrylamide gel electrophoresis coupled with ESI-Q-TOF MS/MS analysis was used to identify differentially expressed proteins between gastric tumor tissues and the corresponding noncancerous tissues. In total, 107 spots with significant alteration (+/-over 2-fold, p < 0.05) were positively identified by MS/MS analysis. Altered expression of representative proteins was validated by RT-PCR and Western blotting. Cluster analysis of the changed proteins revealed an interesting group of metabolic proteins, which suggested accumulation of triiodothyronine (T(3); the major functional component of thyroid hormone) and overexpression of hypoxia-induced factor (HIF) in gastric carcinoma. These observations were further confirmed by electrochemiluminescence immunoassay and immunohistochemistry. T(3)-induced expression of HIF1-alpha and vascular endothelial growth factor was further verified using a gastric cancer cell line and in vivo mouse model. Because the early accumulation of HIF1-alpha was found to be independent of de novo transcription, we also found that the cytosolic cascade phosphatidylinositol 3-kinase/Akt pathway sensitive to T(3) stimulus was involved. Furthermore we demonstrated that T(3)-induced overexpression of HIF1-alpha was mediated by fumarate accumulation and could be enhanced by fumarate hydratase inactivation but inhibited by 2-oxoglutarate. These results provide evidence for alteration of metabolic proteins and dysfunction of thyroid hormone regulation in gastric tumors, and a novel thyroid hormone-mediated tumorigenic signaling pathway is proposed. Our findings are considered a significant step toward a better understanding of adaptations to metabolic stress in gastric carcinogenesis.


Assuntos
Adaptação Fisiológica , Proteômica , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Estresse Fisiológico , Hormônios Tireóideos/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Citratos/metabolismo , Eletroforese em Gel Bidimensional , Fumarato Hidratase/metabolismo , Fumaratos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Espectrometria de Massas , Camundongos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética , Estresse Fisiológico/efeitos dos fármacos , Tri-Iodotironina/metabolismo , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Talanta ; 225: 121991, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592739

RESUMO

A novel signal amplification to detect nucleic acid, called hairpin-mediated nicking enzymatic signal amplification (HNESA), is developed. This method overcomes the limitation of conventional nicking enzymatic signal amplification (NESA) that the target must contain the nicking endonuclease recognition site by using a hairpin probe containing the nicking endonuclease recognition site as an intermediary. Nucleic acid with any sequence can be amplified by HNESA which substantially improves the substrate-scope of traditional NESA. HNESA could detect nucleic acids (ssDNA and RNA) with a detection limit of 8.3 pM at 55 °C. As low as 68 fM could also be detected by integrating HNESA and strand-displacement amplification (SDA). More importantly, HNESA is quite efficient in distinguish single base mismatched sequences. HNESA has potential application for nucleic acid detection in complex biological samples. Therefore, HNESA with high sensitivity and ultrahigh selectivity, should be a promising tool for nucleic acid research, especially for single nucleotide polymorphism (SNP) detection.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , DNA de Cadeia Simples , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Ácidos Nucleicos/genética , RNA
9.
iScience ; 24(10): 103170, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34646996

RESUMO

Taxane-based reagents, such as Taxol, Taxotere, and Abraxane, are popular anti-cancer drugs that can differ in their clinical efficacy. This difference is generally attributed to their active pharmaceutical ingredients. Here, we report a serendipitous discovery that Taxol induces metabolic dysregulation and unfolded protein response. Surprisingly, these effects of Taxol are entirely dependent on its excipient, Cremophor EL (CrEL). We show that CrEL promotes aerobic glycolysis and in turn results in drastic upregulation of angiopoietin like 4 (ANGPTL4), a major regulator of human blood lipid profile. Notably, premedication with dexamethasone further enhances the expression of ANGPTL4. Consistently, we find that the amplitude and frequency of increase in triglycerides is more prominent in Taxol-treated patients with breast cancer. In addition, we find that CrEL activates the unfolded protein response pathway to trigger proinflammatory gene expression and caspase/gasdermin E-dependent pyroptosis. Finally, we discuss the implications of these results in anti-cancer therapies.

10.
Int J Gynecol Cancer ; 20(1): 9-15, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20057284

RESUMO

INSTRUCTION: We used proteomic approaches to identify altered expressed proteins in endometrial carcinoma, with the aim of discovering potential biomarkers or therapeutic targets for endometrial carcinoma. METHODS: The global proteins extracted from endometrial carcinoma and normal endometrial tissues were separated by 2-dimensional electrophoresis and analyzed with PDQuest (Bio-Rad, Hercules, Calif) software. The differentially expressed spots were identified by mass spectrometry and searched against NCBInr protein database. Those proteins with potential roles were confirmed by Western blotting and immunohistochemical assays. RESULTS: Ninety-nine proteins were identified by mass spectrometry, and a cluster diagram analysis indicated that these proteins were involved in metabolism, cell transformation, protein folding, translation and modification, proliferation and apoptosis, signal transduction, cytoskeleton, and so on. In confirmatory immunoblotting and immunohistochemical analyses, overexpressions of epidermal fatty acid-binding protein, calcyphosine, and cyclophilin A were also observed in endometrial carcinoma tissues, which were consistent with the proteomic results. CONCLUSIONS: Our results suggested that these identified proteins, including epidermal fatty acid-binding protein, calcyphosine, and cyclophilin A, might be of potential values in the studies of endometrial carcinogenesis or investigations of diagnostic biomarkers or treatment targets for endometrial carcinoma.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Endométrio/metabolismo , Proteínas de Neoplasias/isolamento & purificação , Proteômica , Adenocarcinoma/etiologia , Adulto , Análise por Conglomerados , Neoplasias do Endométrio/etiologia , Feminino , Humanos , Análise por Pareamento , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Proteoma/análise , Proteômica/métodos , Espectrometria de Massas em Tandem
11.
Mol Cell Proteomics ; 7(10): 1810-23, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18421009

RESUMO

Endometrial carcinoma is one of the most common malignancies of the female genital tract, and there is an urgent need for discovery of novel factors for prognostic assessment and therapeutic targets to endometrial carcinoma. Herein a two-dimensional gel electrophoresis and MALDI-Q-TOF MS/MS-based proteomics approach was used to identify differentially expressed proteins in endometrial carcinoma. Of the 99 proteins identified, cyclophilin A was one of the most significantly altered proteins, and its overexpression was confirmed using RT-PCR and Western blot analyses. Immunohistochemistry suggested a link between cyclophilin A expression and poor differentiation and decreased survival (p < 0.01). Knockdown of cyclophilin A expression by RNA interference led to the significant suppression of the cell growth and the induction of apoptosis in endometrial carcinoma HEC-1-B cells in vitro (p < 0.01) and the inhibition of tumor growth in vivo (p < 0.01). These data suggest that cyclophilin A may serve as a novel prognostic factor and possibly an attractive therapeutic target for endometrial carcinoma.


Assuntos
Ciclofilina A/metabolismo , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/terapia , Proteômica , Adulto , Idoso , Sequência de Aminoácidos , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ciclofilina A/química , Ciclofilina A/genética , Eletroforese em Gel Bidimensional , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Fase G1 , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas de Neoplasias/metabolismo , Estadiamento de Neoplasias , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Int J Cancer ; 123(10): 2377-83, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18729184

RESUMO

With the aim to translate the discovery from proteomic research into clinical applications, we identified epidermal fatty acid-binding protein (E-FABP) and calcyphosine (CAPS) by MALDI-Q-TOF MS and validated their overexpressions by immunoblotting. Their expression statuses were examined by immunohistochemistry in 39 normal endometrium, 29 endometrial intraepithelial neoplasia (EIN) and 84 endometrial cancer (EC) cases. We evaluated the correlations to the clinicopathologic characteristics and determined whether these proteins had prognostic significance. Expressions of E-FABP and CAPS were increased 2.64- and 2.18-fold in EC by immunoblotting. Immunoreactivity of both E-FABP and CAPS were stronger in EC than in EIN or normal tissues (p < 0.001 and < 0.001). Stronger immunoreactivity of E-FABP and CAPS were shown to present with poor differentiation (p = 0.032 and 0.001), but no relevance was observed with staging (p = 1.368 and 4.306). Survival analysis indicated that immunoreactivity of CAPS was correlated to poor survival (p = 0.018), but E-FABP status appeared to be no correlation to the clinical outcome of patients (p = 0.865). Multivariate analysis indicated that CAPS might be an independent prognostic factor for survival in patients with EC (p = 0.008). Results demonstrated the ubiquitous overexpressions of E-FABP and CAPS in EC and the correlations to the clinicopathologic parameters. CAPS might be a potential prognostic factor for survival in patients with EC. The research pattern from proteomics to clinical specimens would have widespread applications.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Epiderme/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteômica , Humanos , Prognóstico
13.
Nat Commun ; 8: 15161, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28443644

RESUMO

Schwann cell (SC) myelination in the peripheral nervous system is essential for motor function, and uncontrolled SC proliferation occurs in cancer. Here, we show that a dual role for Hippo effectors TAZ and YAP in SC proliferation and myelination through modulating G-protein expression and interacting with SOX10, respectively. Developmentally regulated mutagenesis indicates that TAZ/YAP are critical for SC proliferation and differentiation in a stage-dependent manner. Genome-wide occupancy mapping and transcriptome profiling reveal that nuclear TAZ/YAP promote SC proliferation by activating cell cycle regulators, while targeting critical differentiation regulators in cooperation with SOX10 for myelination. We further identify that TAZ targets and represses Gnas, encoding Gαs-protein, which opposes TAZ/YAP activities to decelerate proliferation. Gnas deletion expands SC precursor pools and blocks peripheral myelination. Thus, the Hippo/TAZ/YAP and Gαs-protein feedback circuit functions as a fulcrum balancing SC proliferation and differentiation, providing insights into molecular programming of SC lineage progression and homeostasis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cromograninas/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Bainha de Mielina/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXE/metabolismo , Células de Schwann/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ciclo Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Cromograninas/biossíntese , Subunidades alfa Gs de Proteínas de Ligação ao GTP/biossíntese , Regulação da Expressão Gênica/genética , Células HEK293 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoproteínas/genética , Ratos , Proteínas Repressoras/metabolismo , Transativadores , Fatores de Transcrição HES-1/metabolismo , Proteínas de Sinalização YAP
14.
J Pharm Sci ; 105(1): 50-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26852839

RESUMO

The evaluation of stability with respect to particles in prefilled syringes is complicated by the presence of silicone oil. The mobility, colloidal characteristics, and kinetic instability of silicone oil in contact with a protein formulation may be influenced in unpredictable ways by pharmaceutical variables, storage, and handling conditions. To provide insight into the impact of these variables on silicone oil originating specifically from the siliconized prefillable syringe (PFS), a series of studies were conducted at incremental syringe barrel siliconization levels. Size-exclusion chromatography and particle counting methods were used to quantitate soluble aggregates and submicron and subvisible particles in peginterferon beta-1a in a PFS siliconized with a fixed nozzle spray-on siliconization process. The effect of silicone oil on the peginterferon beta-1a molecule was examined under pharmaceutically relevant conditions, accelerated degradation, and under denaturing conditions. Resonant mass measurement was used to discriminate silicone oil from protein particles establishing that silicone oil does not mask adverse trends in non-silicone oil particles. The peginterferon beta-1a molecule was shown to be stable in the presence of silicone oil and robust with respect to the formation of soluble aggregates and submicron and subvisible particles in its PFS siliconized over the range of 0-1.2 mg silicone oil per syringe barrel.


Assuntos
Interferon beta/química , Polietilenoglicóis/química , Agregados Proteicos , Óleos de Silicone/química , Seringas/normas , Cromatografia em Gel , Estabilidade de Medicamentos , Tamanho da Partícula , Solubilidade
15.
J Pharm Sci ; 94(9): 2030-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16052558

RESUMO

Fourier transform infrared (FTIR) spectroscopy is a powerful tool for monitoring structural changes in lyophilized protein formulations. However, direct measurement of IR spectra requires significant handling time and effort. The possibility of using near infrared (NIR) spectroscopy as a rapid and noninvasive alternative to FTIR is explored in this study. NIR and conventional FTIR spectra were collected for two model proteins, alpha-chymotrypsinogen A and cytochrome c, under conditions of varying stability and structural perturbation. NIR was then compared to FTIR and whereby calibration model was generated by partial least square (PLS) regression to correlate NIR data with FTIR spectra. There is a strong correlation of certain NIR bands with the amide I region of FTIR spectra. It appears that NIR can distinguish damage caused by elevated temperatures and freeze-drying stresses. The ability of sucrose to stabilize the structure of these two proteins can be detected by both methods. It appears that NIR spectroscopy has the potential to provide detailed information on the secondary structure of proteins in the solid state. However, many more examples will be needed to demonstrate fully the ability of NIR to replace FTIR as the standard tool for characterizing lyophilized protein formulations.


Assuntos
Quimotripsinogênio/química , Citocromos c/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Excipientes/química , Liofilização , Desnaturação Proteica , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/química , Temperatura
16.
J Pharm Sci ; 102(2): 347-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23233283

RESUMO

We present evidence that homogeneous submicron particles can influence the growth rate of larger particles upon long-term storage in a temperature-dependent manner. Interferon-beta-1a was thermally stressed at 50°C for 6 h and characterized using nanoparticle tracking analysis (NTA), microflow digital imaging (MFI), and circular dichroism (CD) spectroscopy. This study showed selective formation of submicron particles exhibiting a perturbed protein conformation. These thermally induced submicron particles were spiked into an unstressed solution at three levels, and then monitored for micron-sized particle formation upon storage at 5°C and 25°C for 12 months. The resulting particle growth effects were temperature dependent. NTA and MFI results at 5°C showed little evidence that initial submicron particle levels impacted particle growth across the range ~0.03-25 µm. In contrast, MFI results at 25°C indicated that particle growth in the 1-10 µm size range correlated strongly with initial submicron particle levels, and particle counts in the 10-25 µm size range were highest after 12 months for the samples with highest initial submicron particle content.


Assuntos
Armazenamento de Medicamentos , Interferon beta/química , Microssomos/química , Nanopartículas/química , Armazenamento de Medicamentos/métodos , Interferon beta-1a , Tamanho da Partícula , Soluções Farmacêuticas , Fatores de Tempo
17.
J Pharm Sci ; 100(3): 836-48, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20862672

RESUMO

Solution conditions greatly affect the aggregation rate of a protein. Elucidating these influences provides insight into the critical factors governing aggregation. In this study, recombinant human botulinum protein antigen serotype C [rBoNTC (H(c))] was employed as a model protein. rBoNTC (H(c)) aggregated irreversibly during incubation at 42°C. The aggregation rate was studied as a function of solution conditions, including varying the pH from 3.5 to 8.0 and with or without 150 mM NaCl, 7.5% (w/v) trehalose, and 0.5 M urea. Some solution conditions retarded rBoNTC (H(c)) aggregation, whereas others accelerated aggregation, particularly acidic pH and addition of NaCl or urea. To better understand the mechanism by which these solution conditions influenced aggregation rates, the structure of rBoNTC (H(c)) was characterized using circular dichroism, fluorescence, and ultraviolet absorbance spectroscopies. Conformational stability was assessed from equilibrium urea-induced unfolding studies and by using differential scanning calorimetry (DSC). The activation energy of the aggregation reaction (E(a)) was estimated from an analysis of the heating-rate dependence of the thermal transition observed during DSC heating scans. Overall, for rBoNTC (H(c)), an inverse correlation was found between conformational stability and aggregation rate, as well as between the kinetic barrier to unfolding (i.e., E(a)) and aggregation rate.


Assuntos
Toxinas Botulínicas/química , Dicroísmo Circular , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Soluções Farmacêuticas/química , Conformação Proteica , Dobramento de Proteína , Desdobramento de Proteína , Ureia
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