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1.
FASEB J ; 37(11): e23221, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37795761

RESUMO

Ubiquitin fold modifier 1 is a small ubiquitin-like protein modifier that is essential for embryonic development of metazoans. Although UFMylation has been connected to endoplasmic reticulum homeostasis, the underlying mechanisms and the relevant cellular targets are largely unknown. Here, we show that HRD1, a ubiquitin ligase of ER-associated protein degradation (ERAD), is a novel substrate of UFM1 conjugation. HRD1 interacts with UFMylation components UFL1 and DDRGK1 and is UFMylated at Lys610 residue. In UFL1-depleted cells, the stability of HRD1 is increased and its ubiquitination modification is reduced. In the event of ER stress, the UFMylation and ubiquitination modification of HRD1 is gradually inhibited over time. Alteration of HRD1 Lys610 residue to arginine impairs its ability to degrade unfolded or misfolded proteins to disturb protein processing in ER. These results suggest that UFMylation of HRD1 facilitates ERAD function to maintain ER homeostasis.


Assuntos
Estresse do Retículo Endoplasmático , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Proteínas/metabolismo , Retículo Endoplasmático/metabolismo , Ubiquitina/metabolismo , Homeostase , Degradação Associada com o Retículo Endoplasmático
2.
Part Fibre Toxicol ; 20(1): 38, 2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37807046

RESUMO

Recently, mesoporous nanomaterials with widespread applications have attracted great interest in the field of drug delivery due to their unique structure and good physiochemical properties. As a biomimetic nanomaterial, mesoporous polydopamine (MPDA) possesses both a superior nature and good compatibility, endowing it with good clinical transformation prospects compared with other inorganic mesoporous nanocarriers. However, the subacute toxicity and underlying mechanisms of biomimetic mesoporous polydopamine nanoparticles remain uncertain. Herein, we prepared MPDAs by a soft template method and evaluated their primary physiochemical properties and metabolite toxicity, as well as potential mechanisms. The results demonstrated that MPDA injection at low (3.61 mg/kg) and medium doses (10.87 mg/kg) did not significantly change the body weight, organ index or routine blood parameters. In contrast, high-dose MPDA injection (78.57 mg/kg) is associated with disturbances in the gut microbiota, activation of inflammatory pathways through the abnormal metabolism of bile acids and unsaturated fatty acids, and potential oxidative stress injury. In sum, the MPDA dose applied should be controlled during the treatment. This study first provides a systematic evaluation of metabolite toxicity and related mechanisms for MPDA-based nanoparticles, filling the gap between their research and clinical transformation as a drug delivery nanoplatform.


Assuntos
Biomimética , Nanopartículas , Nanopartículas/toxicidade , Nanopartículas/química , Compostos de Diazônio
3.
J Nanobiotechnology ; 21(1): 268, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568194

RESUMO

Scar formation is a common physiological process that occurs after injury, but in some cases, pathological scars can develop, leading to serious physiological and psychological effects. Unfortunately, there are currently no effective means to intervene in scar formation, and the structural features of scars and their unclear mechanisms make prevention and treatment even more challenging. However, the emergence of nanotechnology in drug delivery systems offers a promising avenue for the prevention and treatment of scars. Nanomaterials possess unique properties that make them well suited for addressing issues related to transdermal drug delivery, drug solubility, and controlled release. Herein, we summarize the recent progress made in the use of nanotechnology for the prevention and treatment of scars. We examine the mechanisms involved and the advantages offered by various types of nanomaterials. We also highlight the outstanding challenges and questions that need to be addressed to maximize the potential of nanotechnology in scar intervention. Overall, with further development, nanotechnology could significantly improve the prevention and treatment of pathological scars, providing a brighter outlook for those affected by this condition.


Assuntos
Cicatriz , Nanoestruturas , Humanos , Cicatriz/tratamento farmacológico , Cicatriz/prevenção & controle , Cicatriz/patologia , Sistemas de Liberação de Fármacos por Nanopartículas , Nanotecnologia , Nanoestruturas/química , Sistemas de Liberação de Medicamentos
4.
J Nanobiotechnology ; 21(1): 105, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964609

RESUMO

Rheumatoid arthritis (RA) is a systemic immune disease characterized by synovial inflammation. Patients with RA commonly experience significant damage to their hand and foot joints, which can lead to joint deformities and even disability. Traditional treatments have several clinical drawbacks, including unclear pharmacological mechanisms and serious side effects. However, the emergence of antibody drugs offers a promising approach to overcome these limitations by specifically targeting interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and other cytokines that are closely related to the onset of RA. This approach reduces the incidence of adverse effects and contributes to significant therapeutic outcomes. Furthermore, combining these antibody drugs with drug delivery nanosystems (DDSs) can improve their tissue accumulation and bioavailability.Herein, we provide a summary of the pathogenesis of RA, the available antibody drugs and DDSs that improve the efficacy of these drugs. However, several challenges need to be addressed in their clinical applications, including patient compliance, stability, immunogenicity, immunosupression, target and synergistic effects. We propose strategies to overcome these limitations. In summary, we are optimistic about the prospects of treating RA with antibody drugs, given their specific targeting mechanisms and the potential benefits of combining them with DDSs.


Assuntos
Anticorpos Monoclonais , Artrite Reumatoide , Humanos , Anticorpos Monoclonais/uso terapêutico , Preparações Farmacêuticas , Artrite Reumatoide/tratamento farmacológico , Inflamação , Citocinas , Fator de Necrose Tumoral alfa
5.
Molecules ; 28(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36903419

RESUMO

The acidic extracellular microenvironment has become an effective target for diagnosing and treating tumors. A pH (low) insertion peptide (pHLIP) is a kind of peptide that can spontaneously fold into a transmembrane helix in an acidic microenvironment, and then insert into and cross the cell membrane for material transfer. The characteristics of the acidic tumor microenvironment provide a new method for pH-targeted molecular imaging and tumor-targeted therapy. As research has increased, the role of pHLIP as an imaging agent carrier in the field of tumor theranostics has become increasingly prominent. In this paper, we describe the current applications of pHLIP-anchored imaging agents for tumor diagnosis and treatment in terms of different molecular imaging methods, including magnetic resonance T1 imaging, magnetic resonance T2 imaging, SPECT/PET, fluorescence imaging, and photoacoustic imaging. Additionally, we discuss relevant challenges and future development prospects.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Peptídeos/química , Imageamento por Ressonância Magnética , Concentração de Íons de Hidrogênio , Microambiente Tumoral
6.
Mol Pharm ; 18(9): 3206-3222, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34337953

RESUMO

Kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD), have become a global public health concern associated with high morbidity, mortality, and healthcare costs. However, at present, very few effective and specific drug therapies are available, owing to the poor therapeutic efficacy and systemic side effects. Kidney-targeted drug delivery, as a potential strategy for solving these problems, has received great attention in the fields of AKI and CKD in recent years. Here, we review the literature on renal targeted, more specifically, renal cell-targeted formulations of AKI and CKD that offered biodistribution data. First, we provide a broad overview of the unique structural characteristics and injured cells of acute and chronic injured kidneys. We then separately summarize literature examples of renal targeted formulations according to the difference of target cells and elaborate on the appropriate formulation design criteria for AKI and CKD. Finally, we propose a hypothetic strategy to improve the renal accumulation of glomerular cell-targeted formulation by escaping the uptake of the reticuloendothelial system and provide some perspectives for future studies.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Glomérulos Renais/metabolismo , Insuficiência Renal Crônica/tratamento farmacológico , Injúria Renal Aguda/patologia , Animais , Modelos Animais de Doenças , Humanos , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Camundongos , Insuficiência Renal Crônica/patologia , Distribuição Tecidual
7.
J Nanobiotechnology ; 19(1): 132, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971910

RESUMO

Molecular imaging technology enables us to observe the physiological or pathological processes in living tissue at the molecular level to accurately diagnose diseases at an early stage. Optical imaging can be employed to achieve the dynamic monitoring of tissue and pathological processes and has promising applications in biomedicine. The traditional first near-infrared (NIR-I) window (NIR-I, range from 700 to 900 nm) imaging technique has been available for more than two decades and has been extensively utilized in clinical diagnosis, treatment and scientific research. Compared with NIR-I, the second NIR window optical imaging (NIR-II, range from 1000 to 1700 nm) technology has low autofluorescence, a high signal-to-noise ratio, a high tissue penetration depth and a large Stokes shift. Recently, this technology has attracted significant attention and has also become a heavily researched topic in biomedicine. In this study, the optical characteristics of different fluorescence nanoprobes and the latest reports regarding the application of NIR-II nanoprobes in different biological tissues will be described. Furthermore, the existing problems and future application perspectives of NIR-II optical imaging probes will also be discussed.


Assuntos
Raios Infravermelhos , Imagem Molecular/métodos , Imagem Óptica/métodos , Animais , Tecnologia Biomédica , Liberação Controlada de Fármacos , Fluorescência , Humanos , Neoplasias/diagnóstico por imagem , Razão Sinal-Ruído , Células-Tronco , Cirurgia Assistida por Computador/métodos
8.
Cancer ; 126(4): 840-849, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31714592

RESUMO

BACKGROUND: The thoracic radiotherapy (TRT) target volume for limited-stage small-cell lung cancer (SCLC) has been controversial for decades. In this report, the final results of a prospective randomized trial on the TRT target volume before and after induction chemotherapy are presented. METHODS: After 2 cycles of etoposide and cisplatin, patients arm were randomized to receive TRT to the postchemotherapy or prechemotherapy tumor volume in a study arm and a control arm. Involved-field radiotherapy was received in both arms. TRT consisted of 1.5 grays (Gy) twice daily in 30 fractions to up to a total dose of 45 Gy. Lymph node regions were contoured, and intentional and incidental radiation doses were recorded. RESULTS: The study was halted early because of slow accrual. Between 2002 and 2017, 159 and 150 patients were randomized to the study arm or the control arm, respectively; and 21.4% and 19.1% of patients, respectively, were staged using positron emission tomography/computed tomography (P = .31). With a median follow-up of 54.1 months (range, 19.9-165.0 months) in survivors, the 3-year local/regional progression-free probability was 58.2% and 65.5% in the study and control arms, respectively (P = .44), and the absolute difference was -7.3% (95% CI, -18.2%, 3.7%). In the study and control arms, the median overall survival was 21.9 months and 26.6 months, respectively, and the 5-year overall survival rate was 22.8% and 28.1%, respectively (P = .26). Grade 3 esophagitis was observed in 5.9% of patients in the study arm versus 15.5% of those in the control arm (P = .01). The isolated out-of-field failure rate was 2.6% in the study arm versus 4.1% in the control arm (P = .46), and all such failures were located in the supraclavicular fossa or contralateral hilum. The regions 7, 3P, 4L, 6, 4R, 5, and 2L received incidental radiation doses >30 Gy. CONCLUSIONS: TRT could be limited to the postchemotherapy tumor volume, and involved-field radiotherapy could be routinely applied for limited-stage SCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pulmonares/terapia , Dosagem Radioterapêutica , Carcinoma de Pequenas Células do Pulmão/terapia , Adulto , Idoso , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Leucopenia/etiologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pneumonia/etiologia , Estudos Prospectivos , Fibrose Pulmonar/etiologia , Relatório de Pesquisa , Carcinoma de Pequenas Células do Pulmão/patologia
9.
J Nanobiotechnology ; 18(1): 80, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32448273

RESUMO

BACKGROUND: Psoriasis is a chronic immune-mediated inflammatory skin disease without effective treatment. The utilization of all trans-retinoic acid (TRA) and betamethasone (BT) for the treatment of psoriasis is still facing difficulties, due to their relatively poor stability, limited skin permeation, and systemic side effects. Flexible liposomes are excellent in deeper skin permeation and reducing the side effects of drugs, which is promising for effective treatment of skin disorders. This work aimed to establish dual-loaded flexible liposomal gel for enhanced therapeutic efficiency of psoriasis based on TRA and BT. RESULTS: Flexible liposomes co-loaded with TRA and BT were successfully prepared in our study. The characterization examination revealed that flexible liposomes featured nano-sized particles (around 70 nm), high drug encapsulation efficiency (> 98%) and sustained drug release behaviors. Flexible liposomes remarkably increased the drug skin permeation and retention as compared with free drugs. Results on HaCaT cells suggested that flexible liposomes were nontoxic, and its cellular uptake has a time-dependent manner. In vivo studies suggested the topical application of TRA and BT dual-loaded liposomal gel had the best ability to reduce the thickness of epidermal and the level of cytokines (TNF-α and IL-6), largely alleviating the symptoms of psoriasis. CONCLUSIONS: Flexible liposomal gel dual-loaded with TRA and BT exerted a synergistic effect, which is a promising topical therapeutic for the treatment of psoriasis.


Assuntos
Betametasona , Fármacos Dermatológicos , Lipossomos , Psoríase , Tretinoína , Animais , Betametasona/química , Betametasona/farmacocinética , Betametasona/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Fármacos Dermatológicos/química , Fármacos Dermatológicos/farmacocinética , Fármacos Dermatológicos/farmacologia , Fármacos Dermatológicos/toxicidade , Modelos Animais de Doenças , Géis , Células HaCaT , Humanos , Lipossomos/química , Lipossomos/farmacocinética , Lipossomos/farmacologia , Lipossomos/toxicidade , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Maleabilidade , Psoríase/tratamento farmacológico , Psoríase/metabolismo , Ratos , Ratos Sprague-Dawley , Tretinoína/química , Tretinoína/farmacocinética , Tretinoína/farmacologia
10.
Nano Lett ; 19(2): 829-838, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30605619

RESUMO

Spinal cord injury (SCI) routinely causes the immediate loss and disruption of neurons followed by complicated secondary injuries, including inflammation, oxidative stress, and dense glial scar formation. Inhibitory factors in the lesion scar and poor intrinsic neural regeneration capacity restrict functional recovery after injury. Minocycline, which has neuroprotective activity, can alleviate secondary injury, but the long-term administration of this drug may cause toxicity. Polysialic acid (PSA) is a large cell-surface carbohydrate that is critical for central nervous system development and is capable of promoting precursor cell migration, axon path finding, and synaptic remodeling; thus, PSA plays a vital role in tissue repair and regeneration. Here, we developed a PSA-based minocycline-loaded nanodrug delivery system (PSM) for the synergistic therapy of spinal cord injury. The prepared PSM exerted marked anti-inflammatory and neuroprotective activities both in vitro and in vivo. The administration of PSM could significantly protect neurons and myelin sheaths from damage, reduce the formation of glial scar, recruit endogenous neural stem cells to the lesion site, and promote the regeneration of neurons and the extension of long axons throughout the glial scar, thereby largely improving the locomotor function of SCI rats and exerting a superior therapeutic effect. The findings might provide a novel strategy for SCI synergistic therapy and the utilization of PSA in other central nervous system diseases.


Assuntos
Antibacterianos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Minociclina/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Ácidos Siálicos/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Micelas , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia
11.
Mol Pharm ; 16(8): 3694-3702, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268329

RESUMO

Therapeutic goals for metastatic breast cancer, including shrinkage of established metastasis and suppression of movement of tumor cells, are often hard to achieve and remain the main obstacles restricting the antimetastatic efficacy of targeted drug delivery systems (TDDSs). Herein, we proposed an E-selectin-targeting nanoplatform for the systemic treatment of metastatic breast cancer. Versatile functions, including killing the circulating tumor cells, shrinking the established lesions, as well as inhibiting the movement of tumor cells, were integrated into doxorubicin-loaded sialic acid-dextran-octadecanoic acid (SDO) micelles (SDD). The prepared SDD micelles could not only inhibit lung and liver metastasis in the orthotopic 4T1 tumors model, but also decrease the metastatic lesions in the metastatic 4T1 cell model, resulting in 27.33% reduced number of metastatic nodules when compared to those without sialic acid modification. It was found that the good antimetastatic effect of SDD was only partially attributed to its ability on removing metastatic cells and metastases. Most importantly, the blank SDO micelles left in the lesion could further inhibit the cell migration and cell-cell binding. These results suggest that SA-driven TDDS has the potential for specific targeting and effective treatment of cancer metastasis.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Selectina E/metabolismo , Nanoconjugados/química , Animais , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Linhagem Celular Tumoral/transplante , Movimento Celular/efeitos dos fármacos , Dextranos/química , Modelos Animais de Doenças , Doxorrubicina/farmacocinética , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Humanos , Ligantes , Camundongos , Micelas , Ácido N-Acetilneuramínico/química , Células Neoplásicas Circulantes/efeitos dos fármacos , Ácidos Esteáricos/química
12.
Mol Pharm ; 15(9): 4235-4246, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30110551

RESUMO

Targeted drug delivery systems (TDDS) have attracted wide attention for their reduced drug side effects and improved antitumor efficacy in comparison with traditional preparations. While targeting moieties in existing TDDS have principally focused on recognition of receptors on the surface of tumor cells, accumulation into tumor tissue only could be performed by enhanced permeability and retention effects and active transportation into tumor cells. Doxorubicin (DOX)-loaded sialic acid-dextran (Dex)-octadecanoic acid (OA) micelles (SA-Dex-OA/DOX) were designed for targeting hepatocellular carcinoma effectively. The synthesized conjugates could self-aggregate to form micelles with a critical micelle concentration of 27.6 µg·mL-1 and diameter of 54.53 ± 3.23 nm. SA-Dex-OA micelles incorporated with 4.36% DOX-loading content could prolong in vitro drug release to 96 h with 80% of final release. Cellular transportation studies revealed that SA-Dex-OA micelles mediated more efficient DOX delivery into Bel-7402 cells than those without SA modification. In vivo biodistribution testing demonstrated that SA-Dex-OA/ICG micelles showed 3.05-fold higher accumulation into Bel-7402 tumors. The recognition of overexpressed E-selectin in inflammatory tumor vascular endothelial cells led to a large accumulation of SA-Dex-OA/ICG micelles into tumor tissue, and the E-selectin upregulated on the surface of tumor cells contributed to active cellular transportation into tumor cells. Accordingly, SA-Dex-OA/DOX exhibited prior suppression of Bel-7402 tumor growth greater than that of Dex-OA/DOX micelles and free DOX (the tumor inhibition: 79.2% vs 61.0 and 51.3%). These results suggest that SA-functionalized micelles with dual targeting properties have high potential for liver cancer therapy.


Assuntos
Dextranos/química , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Micelas , Ácido N-Acetilneuramínico/química , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Selectina E/química , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos Nus , Ácidos Esteáricos/química
13.
Nanomedicine ; 14(7): 2167-2178, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30017962

RESUMO

Effective treatment and real-time monitoring of hepatic cancer are essential. A multifunctional calcium phosphate nanoparticles loading chemotherapeutic agent doxorubicin and magnetic resonance imaging contrast agent diethylenetriaminepentaacetic acid gadolinium (A54-CaP/Gd-DTPA/DOX) was developed for visual targeted therapy of hepatic cancer via T1-weighted MRI in real-time. A54-CaP/Gd-DTPA/DOX exhibited a higher longitudinal relaxivity (6.02 mM-1 s-1) than commercial MR contrast agent Gd-DTPA (3.3765 mM-1 s-1). The DOX release from the nanoparticles exhibited a pH dependent behavior. The cellular uptake results showed that the internalization of A54-CaP/Gd-DTPA/DOX into BEL-7402 cells was1.9-fold faster than that of HepG2 cells via A54 binding. In vivo experiments presented that A54-CaP/Gd-DTPA/DOX had higher distribution and longer retention time in tumor tissue than CaP/Gd-DTPA/DOX and free DOX, and also displayed great antitumor efficacy (95.38% tumor inhibition rate) and lower toxicity. Furthermore, the Gd-DTPA entrapped in the nanoparticles could provide T1-weighted MRI for real-time monitoring the progress of tumor treatment.


Assuntos
Fosfatos de Cálcio/química , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Nanopartículas/administração & dosagem , Fragmentos de Peptídeos/química , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Meios de Contraste , Doxorrubicina/administração & dosagem , Feminino , Gadolínio DTPA/química , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Nanopartículas/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Org Chem ; 81(23): 11813-11818, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27805820

RESUMO

With the combination of Pd(dppf)Cl2 and Cu(OAc)2, a variety of 5-iminopyrrolones were synthesized in moderate to good yields from terminal alkynes, isocyanide, and water via isocyanide double insertion and cycloaddition reaction. A plausible reaction mechanism for this process is depicted. Furthermore, selected compounds 3c, 3e, and 3h exhibited good activities against HepG2 (human liver cancer), NCI-H460 (human lung cancer), and SK-OV-3 (human ovarian cancer) cell lines with IC50 values in the range of 10.63-22.63 µmol L-1.

16.
Chemistry ; 21(3): 984-7, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25430681

RESUMO

Fluorescence-switch-based logic devices are very sensitive compared with most of the reported devices based on UV/Vis absorption systems. Herein, we demonstrate that a simple molecule, 5,10,15,20-tetra-(4-aminophenyl)porphyrin (TAPP), shows protonation-induced multiple emission switches through intramolecular charge transfer and/or aggregation-caused quenching. Highly sensitive INHIBIT and XOR logic gates can be achieved by combining the intermolecular assembly with the intramolecular photoswitching of diprotonated TAPP (TAPPH2(2+)). In addition, molecular simulations have been performed by DFT for a better understanding of the emission-switching processes.

17.
Langmuir ; 31(21): 5851-8, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-25966974

RESUMO

Zwitterionic materials have received great attention because of the non-fouling property. As a result of the electric neutrality of zwitterionic polymers, their layer-by-layer (LBL) assembly is generally conducted under specific conditions, such as very low pH values or ionic strength. The formed multilayers are unstable at high pH or in a high ionic strength environment. Therefore, the formation of highly stable multilayers of zwitterionic polymers via the LBL assembly process is still challenging. Here, we report the LBL assembly of poly(sulfobetaine methacrylate) (PSBMA) with a polyphenol, tannic acid (TA), for protein-resistant surfaces. The assembly process was monitored by a quartz crystal microbalance (QCM) and variable-angle spectroscopic ellipsometry (VASE), which confirms the formation of thin multilayer films. We found that the (TA/PSBMA)n multilayers are stable over a wide pH range of 4-10 and in saline, such as 1 M NaCl or urea solution. The surface morphology and chemical composition were characterized by specular reflectance Fourier transform infrared spectroscopy (FTIR/SR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Furthermore, (TA/PSBMA)n multilayers show high hydrophilicity, with a water contact angle lower than 15°. A QCM was used to record the dynamic protein adsorption process. Adsorption amounts of bovine serum albumin (BSA), lysozyme (Lys), and hemoglobin (Hgb) on (TA/PSBMA)20 multilayers decreased to 0.42, 52.9, and 37.9 ng/cm(2) from 328, 357, and 509 ng/cm(2) on a bare gold chip surface, respectively. In addition, the protein-resistance property depends upon the outmost layer. This work provides new insights into the LBL assembly of zwitterionic polymers.


Assuntos
Metacrilatos/química , Taninos/química , Adsorção , Materiais Biocompatíveis/química , Hemoglobinas/química , Microscopia de Força Atômica , Muramidase/química , Espectroscopia Fotoeletrônica , Técnicas de Microbalança de Cristal de Quartzo , Soroalbumina Bovina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
18.
Nature ; 459(7245): 387-392, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19404261

RESUMO

Mice deficient in the Polycomb repressor Bmi1 develop numerous abnormalities including a severe defect in stem cell self-renewal, alterations in thymocyte maturation and a shortened lifespan. Previous work has implicated de-repression of the Ink4a/Arf (also known as Cdkn2a) locus as mediating many of the aspects of the Bmi1(-/-) phenotype. Here we demonstrate that cells derived from Bmi1(-/-) mice also have impaired mitochondrial function, a marked increase in the intracellular levels of reactive oxygen species and subsequent engagement of the DNA damage response pathway. Furthermore, many of the deficiencies normally observed in Bmi1(-/-) mice improve after either pharmacological treatment with the antioxidant N-acetylcysteine or genetic disruption of the DNA damage response pathway by Chk2 (also known as Chek2) deletion. These results demonstrate that Bmi1 has an unexpected role in maintaining mitochondrial function and redox homeostasis and indicate that the Polycomb family of proteins can coordinately regulate cellular metabolism with stem and progenitor cell function.


Assuntos
Dano ao DNA , Mitocôndrias/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Quinase do Ponto de Checagem 2 , Dano ao DNA/genética , Feminino , Masculino , Camundongos , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Oxirredução/efeitos dos fármacos , Complexo Repressor Polycomb 1 , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/genética , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Timo/citologia , Timo/efeitos dos fármacos
19.
Int J Nanomedicine ; 19: 5739-5761, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882545

RESUMO

Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules that have the capability to induce specific protein degradation. While playing a revolutionary role in effectively degrading the protein of interest (POI), PROTACs encounter certain limitations that impede their clinical translation. These limitations encompass off-target effects, inadequate cell membrane permeability, and the hook effect. The advent of nanotechnology presents a promising avenue to surmount the challenges associated with conventional PROTACs. The utilization of nano-proteolysis targeting chimeras (nano-PROTACs) holds the potential to enhance specific tissue accumulation, augment membrane permeability, and enable controlled release. Consequently, this approach has the capacity to significantly enhance the controllable degradation of target proteins. Additionally, they enable a synergistic effect by combining with other therapeutic strategies. This review comprehensively summarizes the structural basis, advantages, and limitations of PROTACs. Furthermore, it highlights the latest advancements in nanosystems engineered for delivering PROTACs, as well as the development of nano-sized PROTACs employing nanocarriers as linkers. Moreover, it delves into the underlying principles of nanotechnology tailored specifically for PROTACs, alongside the current prospects of clinical research. In conclusion, the integration of nanotechnology into PROTACs harbors vast potential in enhancing the anti-tumor treatment response and expediting clinical translation.


Assuntos
Neoplasias , Proteólise , Humanos , Neoplasias/tratamento farmacológico , Proteólise/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Nanopartículas/química , Nanomedicina/métodos , Nanotecnologia/métodos , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos/química
20.
Pulm Circ ; 14(1): e12351, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38468630

RESUMO

This study aimed to evaluate the effectiveness and safety of an oral sequential triple combination therapy with selexipag after dual combination therapy with endothelin receptor antagonist (ERA) and phosphodiesterase-5 inhibitor (PDE5I)/riociguat in pulmonary arterial hypertension (PAH) patients. A total of 192 PAH patients from 10 centers had received oral sequential selexipag therapy after being on dual-combination therapy with ERA and PDE5i/riociguat for a minimum of 3 months. Clinical data were collected at baseline and after 6 months of treatment. The study analyzed the event-free survival at 6 months and all-cause death over 2 years. At baseline, the distribution of patients among the risk groups was as follows: 22 in the low-risk group, 35 in the intermediate-low-risk group, 91 in the intermediate-high-risk group, and 44 in the high-risk group. After 6 months of treatment, the oral sequential triple combination therapy resulted in reduced NT-proBNP levels (media from 1604 to 678 pg/mL), a decline in the percentage of WHO-FC III/IV (from 79.2% to 60.4%), an increased in the 6MWD (from 325 ± 147 to 378 ± 143 m) and a rise in the percentage of patients with three low-risk criteria (from 5.7% to 13.5%). Among the low-risk group, there was an improvement in the right heart remodeling, marked by a decrease in right atrium area and eccentricity index. The intermediate-low-risk group exhibited significant enhancements in WHO-FC and tricuspid annular plane systolic excursion. For those in the intermediate-high and high-risk groups, there were marked improvements in activity tolerance, as reflected by WHO-FC and 6MWD. The event-free survival rate at 6 months stood at 88%. Over the long-term follow-up, the survival rates at 1 and 2 years were 86.5% and 86.0%, respectively. In conclusion, the oral sequential triple combination therapy enhanced both exercise capacity and cardiac remodeling across PAH patients of different risk stratifications.

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