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1.
Langmuir ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34133189

RESUMO

During froth treatment, a water-in-diluted bitumen emulsion is obtained. The emulsified water contains chloride ions that form hydrochloric acid in downstream oil processing, leading to catalyst deactivation and equipment corrosion. Emulsified water, drops smaller than 10 µm, cannot be effectively removed by gravity settling and centrifugation to below 2 wt %. In this work, a filter-coalescer was used to promote the coalescence and separation of water-in-bitumen emulsion. The larger water drops (>300 µm) exiting the coalescer undergo gravity settling, reducing the water content in diluted bitumen emulsions to values lower than 0.1 vol %. The performance of the coalescer was interpreted via the colloid filtration theory of Rajagopalan and Tien (RT), improved in this work with a coalescence probability (CP) prefactor. This new RTCP framework was able to reproduce the experimental data, allowing its potential use as a predictive model for emulsion filtration and the operation of filter-coalescers. A capillary number analysis was used to account for the detachment of coalesced drops and interpret the drop sizes with different superficial velocities and bed porosities.

2.
Angew Chem Int Ed Engl ; 59(15): 6249-6252, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32017368

RESUMO

Structural morphology is the key parameter for efficacy of nanomedicine. To date, lipid-based nanomaterial has been the most widely used material in nanomedicine and many other biomedical applications. However, to the best of our knowledge, there has not been an in-depth or systematic investigation of the structure-function relationship of lipid-based nanostructures. In this report, we investigated the formulation of novel lipid-based nanostructures via simple tuning of lipid combinations. To prove this concept, we used a combination of various ratios of simple and common phospholipids with different chain lengths (14-carbon chain DMPC: 6-carbon chain DHPC) to find out whether a myriad of novel lipid nanostructures could be obtained. Interestingly, many combinations resulted in distinct lipid nanostructures. Drug encapsulation tests confirmed that they are able to load large amounts of drugs for biological application. In vivo anti-tumor efficacy revealed that certain lipid nanostructures possessed superior tumor retardation effects.


Assuntos
Portadores de Fármacos/química , Engenharia , Nanoestruturas/química , Fosfolipídeos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Camundongos
3.
Proc Natl Acad Sci U S A ; 113(40): E5792-E5801, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27647919

RESUMO

There is a clinical need for new, more effective treatments for chronic wounds in diabetic patients. Lack of epithelial cell migration is a hallmark of nonhealing wounds, and diabetes often involves endothelial dysfunction. Therefore, targeting re-epithelialization, which mainly involves keratinocytes, may improve therapeutic outcomes of current treatments. In this study, we present an integrin-binding prosurvival peptide derived from angiopoietin-1, QHREDGS (glutamine-histidine-arginine-glutamic acid-aspartic acid-glycine-serine), as a therapeutic candidate for diabetic wound treatments by demonstrating its efficacy in promoting the attachment, survival, and collective migration of human primary keratinocytes and the activation of protein kinase B Akt and MAPKp42/44 The QHREDGS peptide, both as a soluble supplement and when immobilized in a substrate, protected keratinocytes against hydrogen peroxide stress in a dose-dependent manner. Collective migration of both normal and diabetic human keratinocytes was promoted on chitosan-collagen films with the immobilized QHREDGS peptide. The clinical relevance was demonstrated further by assessing the chitosan-collagen hydrogel with immobilized QHREDGS in full-thickness excisional wounds in a db/db diabetic mouse model; QHREDGS showed significantly accelerated and enhanced wound closure compared with a clinically approved collagen wound dressing, peptide-free hydrogel, or blank wound controls. The accelerated wound closure resulted primarily from faster re-epithelialization and increased formation of granulation tissue. There were no observable differences in blood vessel density or size within the wound; however, the total number of blood vessels was greater in the peptide-hydrogel-treated wounds. Together, these findings indicate that QHREDGS is a promising candidate for wound-healing interventions that enhance re-epithelialization and the formation of granulation tissue.


Assuntos
Diabetes Mellitus Experimental/patologia , Hidrogéis/farmacologia , Peptídeos/farmacologia , Reepitelização , Sequência de Aminoácidos , Animais , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/farmacologia , Colágeno/farmacologia , Humanos , Peróxido de Hidrogênio/toxicidade , Proteínas Imobilizadas/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Peptídeos/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reepitelização/efeitos dos fármacos
4.
Bioorg Chem ; 75: 106-117, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28926783

RESUMO

A collection of 36 thiosemicarbazone analogues possessed a broad span of tyrosinase inhibitory activities was designed and obtained. Robust and reliable CoMFA and CoMSIA models were gained to predict the structure-activity relationship and the new modifier direction. Inhibitory activities of the compounds were found to greatly depend upon molecular shape, size, and charge. The sterically bulky group at the C-4 position of the thiophene ring contributed a high capacity for biological activity. Some bulky substituents at the C1-position and C12-position, and electron-negative groups at the C3-position, helped to improve the activity of these analogues. The molecular docking results provided visual evidence for QSAR analysis and detailed information about binding mode, affinity, and the principal mechanism between the ligands and tyrosinase. Based on these, a prospective structure modification and optimization of the most potent compound, T32, was suggested for further research.


Assuntos
Inibidores Enzimáticos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Relação Quantitativa Estrutura-Atividade , Tiossemicarbazonas/química , Sítios de Ligação , Domínio Catalítico , Inibidores Enzimáticos/metabolismo , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/metabolismo , Tiossemicarbazonas/metabolismo
5.
BMC Cancer ; 15: 699, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26472563

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is associated with an aggressive clinical course due to the lack of therapeutic targets. Therefore, identifying reliable prognostic biomarkers and novel therapeutic targets for patients with TNBC is required. Proline, glutamic acid, leucine rich protein 1 (PELP1) is a novel steroidal receptor co-regulator, functioning as an oncogene and its expression is maintained in estrogen receptor (ER) negative breast cancers. PELP1 has been proposed as a prognostic biomarker in hormone-related cancers, including luminal-type breast cancers, but its significance in TNBC has not been studied. METHODS: PELP1 immunoreactivity was evaluated using immunohistochemistry in 129 patients with TNBC. Results were correlated with clinicopathological variables including patient's age, tumor size, lymph node stage, tumor grade, clinical stage, histological type, Ki-67 LI, as well as clinical outcome of the patients, including disease-free survival (DFS) and overall survival (OS). RESULTS: PELP1 was localized predominantly in the nuclei of carcinoma cells in TNBC. With the exception of a positive correlation between PELP1 protein expression and lymph node stage (p = 0.027), no significant associations between PELP1 protein expression and other clinicopathological variables, including DFS and OS, were found. However, when PELP1 and Ki-67 LI were grouped together, we found that patients in the PELP1/Ki-67 double high group (n = 48) demonstrated significantly reduced DFS (p = 0.005, log rank test) and OS (p = 0.002, log rank test) than others (n = 81). Multivariable analysis supported PELP1/Ki-67 double high expression as an independent prognostic factor in patients with TNBC, with an adjusted hazard ratio of 2.020 for recurrence (95 % CL, 1.022-3.990; p = 0.043) and of 2.380 for death (95 % CL, 1.138-4.978; p = 0.021). CONCLUSIONS: We found that evaluating both PELP1 and Ki-67 expression in TNBC could enhance the prognostic sensitivity of the two biomarkers. Therefore, we propose that PELP1/Ki-67 double high expression in tumors is an independent prognostic factor for predicting a poor outcome for patients with TNBC.


Assuntos
Biomarcadores Tumorais/biossíntese , Proteínas Correpressoras/biossíntese , Antígeno Ki-67/biossíntese , Prognóstico , Fatores de Transcrição/biossíntese , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Proteínas Correpressoras/genética , Intervalo Livre de Doença , Feminino , Ácido Glutâmico/metabolismo , Humanos , Antígeno Ki-67/genética , Pessoa de Meia-Idade , Prolina/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Fatores de Transcrição/genética , Neoplasias de Mama Triplo Negativas/patologia
6.
J Neurosci ; 33(23): 9592-600, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23739956

RESUMO

Accumulation of α-synuclein (α-syn) in the brain is a core feature of Parkinson disease (PD) and leads to microglial activation, production of inflammatory cytokines and chemokines, T-cell infiltration, and neurodegeneration. Here, we have used both an in vivo mouse model induced by viral overexpression of α-syn as well as in vitro systems to study the role of the MHCII complex in α-syn-induced neuroinflammation and neurodegeneration. We find that in vivo, expression of full-length human α-syn causes striking induction of MHCII expression by microglia, while knock-out of MHCII prevents α-syn-induced microglial activation, antigen presentation, IgG deposition, and the degeneration of dopaminergic neurons. In vitro, treatment of microglia with aggregated α-syn leads to activation of antigen processing and presentation of antigen sufficient to drive CD4 T-cell proliferation and to trigger cytokine release. These results indicate a central role for microglial MHCII in the activation of both the innate and adaptive immune responses to α-syn in PD and suggest that the MHCII signaling complex may be a target of neuroprotective therapies for the disease.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Neurônios Dopaminérgicos/metabolismo , Genes MHC da Classe II/fisiologia , Microglia/metabolismo , Degeneração Neural/metabolismo , alfa-Sinucleína/biossíntese , Animais , Animais Recém-Nascidos , Proliferação de Células , Células Cultivadas , Neurônios Dopaminérgicos/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Degeneração Neural/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
7.
Cancer Immunol Res ; 12(2): 180-194, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38051215

RESUMO

Globally, hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers and a leading cause of cancer-related death. We previously identified an immune evasion pathway whereby tumor cells produce retinoic acid (RA) to promote differentiation of intratumoral monocytes into protumor macrophages. Retinaldehyde dehydrogenase 1 (RALDH1), RALDH2, and RALDH3 are the three isozymes that catalyze RA biosynthesis. In this study, we have identified RALDH1 as the key driver of RA production in HCC and demonstrated the efficacy of RALDH1-selective inhibitors (Raldh1-INH) in suppressing RA production by HCC cells. Raldh1-INH restrained tumor growth in multiple mouse models of HCC by reducing the number and tumor-supporting functions of intratumoral macrophages as well as increasing T-cell infiltration and activation within tumors. Raldh1-INH also displayed favorable pharmacokinetic, pharmacodynamic, and toxicity profiles in mice thereby establishing them as promising new drug candidates for HCC immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Retinal Desidrogenase/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Tretinoína/farmacologia , Tretinoína/metabolismo , Aldeído Oxirredutases/metabolismo
8.
Acta Biomater ; 157: 500-510, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36535568

RESUMO

Angiogenesis inhibition has become a promising therapeutical strategy for cancer treatment. Current clinical anti-angiogenesis treatment includes antibodies against vascular endothelial growth factor (VEGF) or VEGF receptor, fusion proteins with high affinity to VEGF receptor, and tyrosine kinase inhibitors of VEGF receptor. However, current treatments are prone to systemic toxicity or acquiring drug resistance. A natural bioactive lipid 1,2-dipalmitoyl-sn­glycero-3-phosphate (dipalmitoyl phosphatidic acid, DPPA) was reported to exhibit anti-angiogenic and anti-tumoral activity. However, the hydrophobic property of DPPA largely restricted its clinical use, while systemic infusion of free DPPA could result in undesirable side effects. Herein, we successfully developed DPPA-based lipid-nanoparticles (DPPA-LNPs) which turns the "therapeutic payload into nanocarrier". This strategy could improve on DPPA's hydrophiliciy, thereby facilitating its systemic administration. . DPPA-LNPs not only retained the therapeutic anti-angiogenic and anti-tumoral bioactivity of parental DPPA, but also greatly improved its tumor targeting ability via enhanced permeability and retention (EPR) effect. This strategy not only eliminates the limitation of drug encapsulation rate, toxicity of the delivery vehicle; but also enhances DPPA bioacvtity in vitro and in vivo. Systemic administration of DPPA-LNPs significantly suppressed the blood vessel formation and tumor growth of triple negative breast cancer and liver cancer growth on both xenograft tumor models. STATEMENT OF SIGNIFICANCE: This is the first-in-kind self-therapeutic inherent lipid to be made into a nanocarrier, with inherent anti-angiogenic and anti-tumor properties. DPPA nanocarrier is fully natural, fully compatible with minimal systemic toxicity. DPPA nanocarrier can accumulate at high concentration at tumor via EPR effect, exerting both anti-angiogenic and anti-tumor effects in vivo. DPPA nanocarrier could be used to encapsulate biologics or small molecules for synergistic anti-cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Linhagem Celular Tumoral , Lipídeos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neovascularização Patológica/patologia , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais
9.
ACS Nano ; 17(15): 14424-14441, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498878

RESUMO

High expression of programmed death ligand 1 (PD-L1) and strong immune evasion ability of the tumor microenvironment (TME) are maintained through mutual regulation between different immune and stromal cells, which causes obstructions for cancer immunotherapy, especially immunosuppressive M2-like phenotype tumor-associated macrophages (TAMs). Repolarization of TAMs to the M1-like phenotype could secrete proinflammatory cytokines and reverse the immunosuppressive state of the TME. However, we found that reactive oxygen species (ROS) generated by repolarized TAMs could be a double-edged sword: ROS cause a stronger suppressive effect on CD8 T cells through an increased proportion of apoptotic regulatory T (Treg) cells. Thus, simply repolarizing TAMs while ignoring the suppressed function of T cells is insufficient for generating adequate antitumor immunity. Accordingly, we engineered multifunctional redox-responsive nanoplatform NPs (M+C+siPD-L1) with Toll-like receptor agonist (M), catalase (C), and siPD-L1 encased for coregulation of both TAMs and T cells to maximize cancer immunotherapy. Our results demonstrated that NPs (M+C+siPD-L1) showed superior biocompatibility and intratumor accumulation. For in vitro experiments, NPs (M+C+siPD-L1) simultaneously repolarized TAMs to the M1-like phenotype, hydrolyzed extra ROS, knocked down the expression of PD-L1 on tumor cells, and rescued the function of CD8 T cells suppressed by Treg cells. In both orthotopic Hepa1-6 and 4T1 tumor-bearing mouse models, NPs (M+C+siPD-L1) could effectively evoke active systemic antitumor immunity and inhibit tumor growth. The combination of repolarizing TAMs, hydrolyzing extra ROS, and knocking down the expression of PD-L1 proves to be a synergistic approach in cancer immunotherapy.


Assuntos
Antígeno B7-H1 , Neoplasias , Camundongos , Animais , Antígeno B7-H1/genética , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/metabolismo , Neoplasias/metabolismo , Imunoterapia , Imunossupressores/farmacologia , Microambiente Tumoral , Linhagem Celular Tumoral
10.
J Neuroinflammation ; 9: 259, 2012 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-23186369

RESUMO

BACKGROUND: The protein alpha-synuclein (α-SYN), which is found in the Lewy bodies of dopamine-producing (DA) neurons in the substantia nigra (SN), has an important role in the pathogenesis of Parkinson's disease (PD). Previous studies have shown that neuroinflammation plays a key role in PD pathogenesis. In an AAV-synuclein mouse model of PD, we have found that over-abundance of α-SYN triggers the expression of NF-κB p65, and leads to microglial activation and DA neurodegeneration. We also have observed that Fcγ receptors (FcγR), proteins present on the surface of microglia that bind immunoglobulin G (IgG) and other ligands, are key modulators of α-SYN-induced neurodegeneration. METHODS: In order to study the role of FcγRs in the interactions of α-SYN and microglia, we treated the primary microglial cultures from wild-type (WT) and FcγR-/- mice with aggregated human α-SYN in vitro. RESULTS: Using immunocytochemistry, we found that α-SYN was taken up by both WT and FcγR-/- microglia, however, their patterns of internalization were different, with aggregation in autophagosomes in WT cells and more diffuse localization in FcγR-/- microglia. In WT microglia, α-SYN induced the nuclear accumulation of NF-κB p65 protein and downstream chemokine expression while in FcγR-/- mouse microglia, α-SYN failed to trigger the enhancement of nuclear NF-κB p65, and the pro-inflammatory signaling was reduced. CONCLUSIONS: Our results suggest that α-SYN can interact directly with microglia and can be internalized and trafficked to autophagosomes. FcγRs mediate this interaction, and in the absence of the gamma chain, there is altered intracellular trafficking and attenuation of pro-inflammatory NF-κB signaling. Therefore, blocking either FcγR signaling or downstream NF-κB activation may be viable therapeutic strategies in PD.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Microglia/efeitos dos fármacos , Receptores de IgG/metabolismo , Transdução de Sinais/efeitos dos fármacos , alfa-Sinucleína/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Células Cultivadas , Citocinas/genética , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica/genética , Humanos , Antígenos Comuns de Leucócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Biossíntese de Proteínas/genética , Receptores de IgG/deficiência , Fatores de Tempo , alfa-Sinucleína/metabolismo
11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 43(5): 683-6, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23230738

RESUMO

OBJECTIVE: To evaluate the expressions and significances of CD147, OPN and MMP-2 in oral squamous cell carcinoma (OSCC). METHODS: The expressions of CD147, OPN and MMP-2 were detected by immunohistochemical method (SP) in 35 cases of ()SCC. The relationships between the expressions of CD147, OPN and MMP-2 and clinic histopathologic parameters of OSCC were analyzed. RESULTS: The expression rates of CD147, OPN and MMP-2 in OSCC tissues were 65.71%, 71.43% and 68.57% respectively. The expressions of CD147, OPN and MMP-2 were positively correlated with tumor histopathologic type, clinical stage and lymph node metastasis (P < 0.05), but not correlated with age, gender and the location of tumor (P > 0.05). The positive correlations were found among the expressions of CD147, OPN and MMP-2 (MMP-2 and CD147, r = 0. 653; MMP-2 and OPN, r = 0.540; CD147 and OPN, r = 0.381; P < 0.05). CONCLUSION: The expressions of CD147, OPN and MMP-2 increase in OSCC and may be the potential predictor of the malignant degree of OSCC.


Assuntos
Basigina/metabolismo , Carcinoma de Células Escamosas/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Neoplasias Bucais/metabolismo , Osteopontina/metabolismo , Idoso , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Estadiamento de Neoplasias
12.
Biomaterials ; 280: 121264, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34823884

RESUMO

Pancreatic cancer (PAC) is one of the most lethal malignant neoplasms with poor prognosis and high mortality. Emerging evidence has revealed that abnormal tumor lipid metabolism and tumor-associated macrophages (TAMs) significantly contribute to PAC development and progression. Therefore, concurrently reprogramming tumor lipid metabolism and regulating TAMs function could be a promising strategy for effective PAC therapy. Herein, we identified an important enzyme catabolizing lipids (monoacylglycerol lipase, MGLL) and a key receptor regulating macrophage phenotype (endocannabinoid receptor-2, CB-2) that are over-expressed in PAC cells and on TAMs, respectively. Based on this finding, we developed a reduction-responsive poly (disulfide amide) (PDSA)-based nanoplatform for systemic co-delivery of MGLL siRNA (siMGLL) and CB-2 siRNA (siCB-2). This nanoplatform could utilize its reduction-responsive characteristic to rapidly release siRNA for efficient silencing of MGLL and CB-2, inducing concurrent suppression of free fatty acids (FFAs) generation in PAC cells and repolarization of TAMs into tumor-inhibiting M1-like phenotype. With this suppressed FFAs generation to inhibit nutrient supply for tumor cells and repolarized TAMs to secrete tumoricidal cytokines such as TNF-α and IL-12, a combinational anticancer effect could be achieved in both xenograft and orthotopic PAC tumor models.


Assuntos
Metabolismo dos Lipídeos , Neoplasias Pancreáticas , Humanos , Imunoterapia , Macrófagos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Interferência de RNA , Microambiente Tumoral
13.
Zhongguo Zhong Yao Za Zhi ; 36(10): 1316-8, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21837973

RESUMO

OBJECTIVE: To study the chemical constituents of Daphne odora var. margirmta. METHOD: The compounds were isolated and purified by column chromatography of silica gel, ODS, Sephadex LH-20, and their structures were identified by UV, 1H-NMR, 13C-NMR, MS and CD spectroscopic methods. RESULT: Ten compounds were elucidated as wikatrols B (1), kaempferol (2), daphnodorin B (3), daphnodorin D2 (4), daphnodorin A (5), daphnodorin C (6), daphnodorin D1 (7), daphnodorin I (8), daphnetin (9), daphnoretin (10). CONCLUSION: Compounds 1,2,4 were obtained from this plant for the first time,and compound 1 was isolated firstly from the genus Daphne.


Assuntos
Daphne/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Raízes de Plantas/química
14.
STAR Protoc ; 2(1): 100275, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33511358

RESUMO

Targeted regulation of mitochondrial gene expression is challenging due to the lack of a mitochondria-specific delivery system. We have previously developed various stimuli-responsive nanoparticle (NP)-based delivery systems to transport nucleic acids for regulation of target gene expression. This protocol describes the design and preparation of an NP platform for mitochondria-specific gene delivery (mito-NP). We use mito-NP in primary liver fibroblasts that are transplanted into mice. Mito-NP can be used to deliver various nucleic acid therapeutics and to treat mitochondria-regulated diseases. For complete details on the use and execution of this protocol, please refer to Zhao et al. (2020).


Assuntos
Fibroblastos , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Fígado/metabolismo , Mitocôndrias Hepáticas , Animais , Fibroblastos/metabolismo , Fibroblastos/transplante , Humanos , Camundongos , Mitocôndrias Hepáticas/genética , Mitocôndrias Hepáticas/metabolismo
15.
Int J Nanomedicine ; 16: 5909-5921, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34475756

RESUMO

Since the discovery of RNA interference (RNAi), RNAi technology has rapidly developed into an efficient tool for post-transcriptional gene silencing, which has been widely used for clinical or preclinical treatment of various diseases including cancer. Small interfering RNA (siRNA) is the effector molecule of RNAi technology. However, as polyanionic macromolecules, naked siRNAs have a short circulatory half-life (<15 min) and is rapidly cleared by renal filtration, which greatly hinders their clinical application. Furthermore, the anionic and macromolecular characteristics of naked siRNAs impede their readiness to cross the cell membrane and therefore delivery vehicles are required to facilitate the cellular uptake and cytosolic delivery of naked siRNAs. In the past decade, numerous nanoparticles (NPs) such as liposomes have been employed for in vivo siRNA delivery, which have achieved favorable therapeutic outcomes in clinical disease treatment. In particular, because tumor microenvironment (TME) or tumor cells show several distinguishing biological/endogenous factors (eg, pH, enzymes, redox, and hypoxia) compared to normal tissues or cells, much attention has recently paid to design and construct TME-responsive NPs for multistaged siRNA delivery, which can respond to biological stimuli to achieve efficient in vivo gene silencing and better anticancer effect. In this review, we summarize recent advances in TME-responsive siRNA delivery systems, especially multistage delivery NPs, and discuss their design principles, functions, effects, and prospects.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Interferência de RNA , RNA Interferente Pequeno/genética , Microambiente Tumoral
16.
Pathol Oncol Res ; 27: 582443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257530

RESUMO

The expression of Proline-, glutamic acid-, and leucine-rich protein 1 (PELP1) has been reported to be dysregulated in non-small cell lung carcinoma, especially in lung adenocarcinoma (LUAD). Therefore, we aimed to investigate the functional and prognostic roles of PELP1 in LUAD in this study. We first immunolocalized PELP1 in 76 cases of LUAD and 17 non-pathological or tumorous lung (NTL) tissue specimens and correlated the findings with the clinicopathological parameters of the patients. We then performed in vitro analysis including MTT, flow cytometry, wound healing, and transwell assays in order to further explore the biological roles of PELP1 in 17-ß-estradiol (E2) induced cell proliferation, migration, and invasion of LUAD cells. We subsequently evaluated the prognostic significance of PELP1 in LUAD patients using the online survival analysis tool Kaplan-Meier Plotter. The status of PELP1 immunoreactivity in LUAD was significantly higher than that in the NTL tissues and significantly positively correlated with less differentiated features of carcinoma cells, positive lymph node metastasis, higher clinical stage as well as the status of ERα, ERß, and PCNA. In vitro study did reveal that E2 promoted cell proliferation and migration and elevated PELP1 protein level in PELP1-high A549 and H1975 cells but not in PELP1-low H-1299 cells. Knock down of PELP1 significantly attenuated E2 induced cell proliferation, colony formation, cell cycle progress as well as migration and invasion of A549 and H1975 cells. Kaplan-Meier Plotter revealed that LUAD cases harboring higher PELP1 expression had significantly shorter overall survival. In summary, PELP1 played a pivotal role in the estrogen-induced aggressive transformation of LUAD and could represent adverse clinical outcome of the LUAD patients.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Proteínas Correpressoras/metabolismo , Estradiol/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas Correpressoras/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Fatores de Transcrição/genética
17.
Int J Mol Sci ; 11(11): 4750-63, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-21151469

RESUMO

Optimization of total flavonoid compound (TFC) extraction from Gynura medica leaf was investigated using response surface methodology (RSM) in this paper. The conditions investigated were 30-60% (v/v) ethanol concentration (X(1)), 85-95 °C extraction temperature (X(2)) and 30-50 (v/w) liquid-to-solid ratio (X(3)). Statistical analysis of the experiments indicated that temperature and liquid-to-solid ratio significantly affected TFC extraction (p < 0.01). The Box-Behnken experiment design showed that polynomial regression models were in good agreement with the experimental results, with the coefficients of determination of 0.9325 for TFC yield. The optimal conditions for maximum TFC yield were 55% ethanol, 92 °C and 50 (v/w) liquid-to-solid ratio with a 30 min extraction time. Extracts from these conditions showed a moderate antioxidant value of 54.78 µmol quercetin/g dry material (DM), 137.3 µmol trolox/g DM for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 108.21 µmol quercetin/g DM, 242.31 µmol trolox/g DM for 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS(+)), respectively. HPLC-DAD-MS analysis showed that kaempferol-3-O-glucoside was the principal flavonoid compound in Gynura medica leaf.


Assuntos
Antioxidantes/isolamento & purificação , Asteraceae/química , Fracionamento Químico/métodos , Flavonoides/isolamento & purificação , Antioxidantes/química , Flavonoides/química , Oxirredução , Folhas de Planta/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-32548111

RESUMO

Macrophages are mainly divided into two phenotypes: M1-like (anti-tumoral, pro-inflammatory) and M2-like (pro-tumoral, anti-inflammatory). The more abundant M2-like phenotype of tumor associated macrophages (TAMs) has been associated with poor prognosis in various cancers, therefore, many studies have been carried out to modulate TAMs to change from an M2 to M1-like phenotype as an effective way to suppress tumor growth. Previous study indicated that the FDA-approved Ferumoxytol is an iron oxide nanoparticle that has intrinsic tumor inhibiting properties and is accompanied by the increased presence of the pro-inflammatory, anti-tumoral M1-like phenotype. Intrigued by this finding, we hypothesize that differently charged super-paramagnetic iron oxide nanoparticles (SPIONs) would have preferential differences in polarizing macrophages. Herein, we report that differently charged SPIONs have distinct preferences in the modulation of TAM phenotypes. Positively charged SPION (S+) had the highest cellular uptake and highest macrophage polarization effect. Interestingly, although negatively charged SPION (S-) should present charge-charge repulsion with cell membranes, they showed considerably high uptake in vitro, nevertheless presenting the highest cellular toxicity. Neutrally charged SPION (SN) showed minimal uptake and cellular toxicity in vitro. Both S+ and S- could effectively re-polarize M2-like macrophages toward M1-like macrophages in vitro, and significantly increased the Fenton effect and chemotaxis of macrophages. When macrophages pre-treated with these SPIONs were co-injected with tumor cells to obtain a tumor xenograft, S+ and S- treated macrophages significantly induced tumor retardation, indicating the successful repolarization of tumor macrophages by these SPIONs. Taken together, we provide an insight on the importance of SPION charge in immunomodulation of macrophages.

19.
Front Pharmacol ; 11: 539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425785

RESUMO

The research of lipid nanoparticles (LNPs) has been ongoing for more than three decades, and more research are still being carried out today. Being the first Food and Drug Administration (FDA)-approved nanomedicine, LNPs not only provide various advantages, but also display some unique properties. The unique lipid bilayer structure of LNPs allows it to encapsulate both fat-soluble and water-soluble molecules, hence enabling a wide range of possibilities for the delivery of therapeutic agents with different physical and chemical properties. The ultra-small size of some LNPs confers them the ability to cross the blood brain barrier (BBB), thus obtaining superiority in the treatment of diseases of the central nervous system (CNS). The ability of tumor targeting is one of the basic requirements to be an excellent delivery system, where the LNPs have to reach the interior of the tumor. Factors that influence tumor extravasation and the permeability of LNPs are size, surface charge, lipid composition, and shape. The effect of size, surface charge, and lipid composition on the cellular uptake of LNPs is no longer recent news, while increasing numbers of researchers are interested in the effect of shape on the uptake of LNPs and its consequential effects. In our study, we prepared three lipid nanostars (LNSs) by mixing phosphatidylcholine (PC) with different backbone lengths (C14:C4 or C16:C6 or C18:C8) at a 3:1 ratio. Although several star-shaped nanocarriers have been reported, these are the first reported star-shaped LNPs. These LNSs were proven to be safe, similar in size with their spherical controls (~100 nm), and stable at 37°C. The release rate of these LNSs are inversely related to the length of the lipid backbone. Most importantly, these LNSs exhibited greatly enhanced cellular uptake and in vivo tumor extravasation compared with their spherical controls. Based on the different uptake and pharmacokinetic characteristics displayed by these LNSs, numerous route formulations could be taken into consideration, such as via injection or transdermal patch. Due to their excellent cellular uptake and in vivo tumor accumulation, these LNSs show exciting potential for application in cancer therapy.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(12): 3369-74, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20210172

RESUMO

Under the imitated physiological conditions (pH = 7.4), the interactions of two novel genistein esterified derivatives, genistein 7-acetylferulic acid ester and genistein 7, 4'-di-acetylferulic acid ester (1 and 2), with bovine serum albumin (BSA) were investigated by the fluorescence and UV-Vis spectroscopy. It was observed that both of them can effectively quench the intrinsic fluorescence of BSA. The results suggested that the fluorescence quenching process of BSA at low concentrations of the compounds may be mainly governed by static quenching mechanisms. The binding constants (KA) and the number of binding sites (n) at different temperatures were calculated. From the thermodynamic parameters, it can be judged that the binding of 1 to BSA involved electrostatic interactions, whereas the binding of 2 to BSA involved hydrogen bonds and Van der Waals forces. The binding average distances r between BSA (donor) and the compounds (acceptor) were determined to be 2.63 nm and 2.92 nm respectively based on the Forster theory. Besides, the interactions of BSA with the compounds did not change the conformation of BSA and the binding of compounds to BSA is near tryptophan subunit via synchronous fluorescence spectrometry.


Assuntos
Genisteína/química , Soroalbumina Bovina/química , Animais , Bovinos , Conformação Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Triptofano/química
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