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1.
Asian J Surg ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38443248

RESUMO

The differences in the safety and efficacy of anticoagulation between different types of new oral anticoagulants(NOACs) and low molecular weight heparin(LMWH) are still controversial. The main purposes of this study were to analyze safety and efficacy of NOACs versus LMWH for thromboprophylaxis, and perform subgroup analyses stratified by individual NOACs and different populations after total hip arthroplasty (THA) or total knee arthroplasty (TKA). Literature search was performed in PubMed, EMBASE, Cochrane Library, CNKI and Wanfang databases until June 31, 2022. This systematic review and meta-analysis included 46 randomized controlled trials (RCT) with 39, 924 patients. We evaluated the safety and efficacy of thromboprophylaxis between LMWH and NOACs. NOACs were more effective in reducing deep vein thrombosis (DVT) (RR0.59; 95%CI 0.49-0.71) and adverse events (RR: 0.96; 95%CI: 0.93-0.99) than LMWH. The subgroup analyses for different anticoagulants revealed that rivaroxaban (RR:0.49; 95%CI:0.36-0.66), apixaban (RR: 0.54; 95%CI: 0.36-0.81) and edoxaban (RR:0.49; 95%CI: 0.32-0.75) have the lower risk of DVT than LMWH. Apixaban (RR:0.89; 95%CI: 0.80-1.00) had superior prevention of bleeding to LMWH. Edoxaban exhibited a lower risk of VTE (RR: 0.46; 95%CI: 0.33-0.65), advantage events (RR: 0.87; 95%CI: 0.82-0.93), and drug-related adverse events (DRAEs) (RR: 0.64; 95%CI: 0.53-0.76) than LMWH. East Asian population was superior to western population for preventing DVT, advantage events, and DRAE using NOACs. In conclusion, NOACs are more effective than LMWH at preventing DVT and adverse events after arthroplasty. Apixaban has lower bleeding than LMWH, and East Asian populations may benefit more than western population from NOACs.

2.
Nat Cell Biol ; 26(1): 124-137, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168770

RESUMO

The gut microbiota play a pivotal role in human health. Emerging evidence indicates that gut microbes participate in the progression of tumorigenesis through the generation of carcinogenic metabolites. However, the underlying molecular mechanism is largely unknown. In the present study we show that a tryptophan metabolite derived from Peptostreptococcus anaerobius, trans-3-indoleacrylic acid (IDA), facilitates colorectal carcinogenesis. Mechanistically, IDA acts as an endogenous ligand of an aryl hydrocarbon receptor (AHR) to transcriptionally upregulate the expression of ALDH1A3 (aldehyde dehydrogenase 1 family member A3), which utilizes retinal as a substrate to generate NADH, essential for ferroptosis-suppressor protein 1(FSP1)-mediated synthesis of reduced coenzyme Q10. Loss of AHR or ALDH1A3 largely abrogates IDA-promoted tumour development both in vitro and in vivo. It is interesting that P. anaerobius is significantly enriched in patients with colorectal cancer (CRC). IDA treatment or implantation of P. anaerobius promotes CRC progression in both xenograft model and ApcMin/+ mice. Together, our findings demonstrate that targeting the IDA-AHR-ALDH1A3 axis should be promising for ferroptosis-related CRC treatment.


Assuntos
Neoplasias Colorretais , Ferroptose , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Ferroptose/genética , Carcinogênese/genética , Transformação Celular Neoplásica , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia
3.
Cytokine ; 173: 156442, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995395

RESUMO

PURPOSE: The characteristics of cytokine/chemokine(CK) profiles across different courses of chronic hepatitis B virus infection and the effects of NAs antiviral therapy on cytokine profiles remain unclear. METHODS: This report provides evidence from 383 patients with chronic HBV infection. The Luminex multiple cytokine detection technology was used to detect CK profiles. The predictive power of CKs across course of disease was assessedusing univariate analyses and with receiver operating characteristic (ROC) curves. RESULTS: Compared to healthy control (HC), expression levels of interleukin 6 (IL)-6, IL-8, IL-21, matrix metalloproteinases (MMP)-2 and tumor necrosis factor receptor (TNFR)-1 showed a significant increasing trend during chronic HBV infection. IL-23 and IL-33 increased respectively in chronic hepatitis B patients (CHB). interferon (IFN)-gamma and TNF-α changed significantly only in liver cirrhosis (LC) patients. Whereas, myeloid-related markers decreased dramatically in those with hepatocellular carcinoma (HCC). The ROC result suggests that combining IL-6, IL-8, CXCL9 and CXCL13 into a nomogram has closely correlation with HCC during chronic HBV infection. In addition, nucleotide analogues (NAs) antiviral treatments are capable of recoveringnormal liver functions and significantly reducing the viral loads, however, they seem to have a limited effect in changing CKs, especially specific antiviral factors. CONCLUSION: The differential CK and virological markers may serve as potential indicators of distinct immune statuses in chronic HBV infection. They also underscore the varying efficacy and limitations of NAs antiviral therapies. This next step would to break new ground in the optimization of current anti-HBV treatment programs although this requires further research.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B , Nucleotídeos , Interleucina-8 , Citocinas/metabolismo , Antivirais/uso terapêutico
4.
Nat Commun ; 14(1): 5933, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739943

RESUMO

Ferroptosis suppressor protein 1 (FSP1, also known as AIMF2, AMID or PRG3) is a recently identified glutathione-independent ferroptosis suppressor1-3, but its underlying structural mechanism remains unknown. Here we report the crystal structures of Gallus gallus FSP1 in its substrate-free and ubiquinone-bound forms. The structures reveal a FAD-binding domain and a NAD(P)H-binding domain, both of which are shared with AIF and NADH oxidoreductases4-9, and a characteristic carboxy-terminal domain as well. We demonstrate that the carboxy-terminal domain is crucial for the catalytic activity and ferroptosis inhibition of FSP1 by mediating the functional dimerization of FSP1, and the formation of two active sites located on two sides of FAD, which are responsible for ubiquinone reduction and a unique FAD hydroxylation respectively. We also identify that FSP1 can catalyze the production of H2O2 and the conversion of FAD to 6-hydroxy-FAD in the presence of oxygen and NAD(P)H in vitro, and 6-hydroxy-FAD directly inhibits ferroptosis in cells. Together, these findings further our understanding on the catalytic and ferroptosis suppression mechanisms of FSP1 and establish 6-hydroxy-FAD as an active cofactor in FSP1 and a potent radical-trapping antioxidant in ferroptosis inhibition.


Assuntos
Ferroptose , Peróxido de Hidrogênio , NAD , Ubiquinona , Catálise
5.
Adv Sci (Weinh) ; 10(6): e2204006, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36627132

RESUMO

Emerging evidence reveals that amino acid metabolism plays an important role in ferroptotic cell death. The conversion of methionine to cysteine is well known to protect tumour cells from ferroptosis upon cysteine starvation through transamination. However, whether amino acids-produced metabolites participate in ferroptosis independent of the cysteine pathway is largely unknown. Here, the authors show that the tryptophan metabolites serotonin (5-HT) and 3-hydroxyanthranilic acid (3-HA) remarkably facilitate tumour cells to escape from ferroptosis distinct from cysteine-mediated ferroptosis inhibition. Mechanistically, both 5-HT and 3-HA act as potent radical trapping antioxidants (RTA) to eliminate lipid peroxidation, thereby inhibiting ferroptotic cell death. Monoamine oxidase A (MAOA) markedly abrogates the protective effect of 5-HT via degrading 5-HT. Deficiency of MAOA renders cancer cells resistant to ferroptosis upon 5-HT treatment. Kynureninase (KYNU), which is essential for 3-HA production, confers cells resistant to ferroptotic cell death, whereas 3-hydroxyanthranilate 3,4-dioxygenase (HAAO) significantly blocks 3-HA mediated ferroptosis inhibition by consuming 3-HA. In addition, the expression level of HAAO is positively correlated with lipid peroxidation and clinical outcome. Together, the findings demonstrate that tryptophan metabolism works as a new anti-ferroptotic pathway to promote tumour growth, and targeting this pathway will be a promising therapeutic approach for cancer treatment.


Assuntos
Neoplasias , Triptofano , Humanos , Triptofano/metabolismo , Cisteína/metabolismo , Serotonina/metabolismo , Neoplasias/tratamento farmacológico , Peroxidação de Lipídeos
6.
PeerJ ; 10: e14574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570013

RESUMO

Fruit peel creasing is a serious pre-harvest physiological disorder in citrus, influencing fruit quality, storage, and yield. Four- and eight-year-old 'Hongjiang' oranges grafted onto Canton lemon rootstocks were treated with calcium and calcium inhibitors, respectively, to study the effects of different treatments on fruit creasing rate, mechanical properties of the peel, cell wall metabolism enzyme activities, and the expression of related genes. Foliar application of 0.5% calcium nitrate significantly reduced the fruit creasing rate, while treatment with EGTA and LaCl3, inhibitors of calcium uptake, increased the fruit creasing rate; But the effect of calcium nitrate treatment on changing the mechanical properties of pericarp and inhibiting the activity of hydrolase (PG, Cx and PE) was not very significant. Furthermore, it was observed that the expression levels of genes (PG, Cx, and PE) encoding cell wall-degrading enzymes were significantly lower in the normal fruit peel than in the creased fruit peel. Meanwhile, the expression levels of PG, Cx, and PE were higher in the peel of shaded fruit than in the peel of exposed fruit. During the high incidence period of fruit creasing, calcium nitrate treatment down-regulated the expression of PG, Cx, and PE, while EGTA treatment up-regulated the expression of these genes. In conclusion, foliar spraying of calcium nitrate at the fruit rapid enlargement stage can increase the Ca content in the peel of 'Hongjiang' orange and significantly suppress the expression of cell wall degrading enzymes genes (PG, PE and Cx) in 'Hongjiang' orange peel during the high occurrence period of fruit creasing, resulting in reducing the occurrence of fruit creasing and cracking.


Assuntos
Citrus sinensis , Citrus , Citrus/genética , Frutas/genética , Ácido Egtázico/metabolismo , Citrus sinensis/genética , Parede Celular/genética
7.
Front Public Health ; 10: 1037508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388269

RESUMO

Background and aim: Chronic hepatitis B (CHB) can be divided into immune tolerance (IT), immune clearance (IC), hepatitis B e antigen (HBeAg)-negative inactive/quiescent carrier (ENQ), and HBeAg-negative hepatitis (ENH) phases. The conventional biomarkers used to distinguish these phases have limitations. We examined the clinical significance of hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) as novel biomarkers. Methods: One hundred eighty-nine patients without treatment currently were categorized by CHB phase (IT = 46, IC = 45, ENQ = 49, ENH = 49). The associations of HBV RNA and HBcrAg with HBV DNA and alanine transaminase (ALT) were analyzed. The decision tree model was used to distinguish the four phases in the natural course of CHB. Results: The concentrations of HBV RNA and HBcrAg were highest in the IT and IC phases (P < 0.01). Serum HBV RNA was similar to HBcrAg in treatment-naïve patients. HBV RNA and HBcrAg correlated with HBV DNA in the HBeAg+ and HBeAg- status (HBV RNA: e+ r = 0.51, e- r = 0.62; HBcrAg: e+ r = 0.51, e- r = 0.71), but their association with HBV DNA differed among phases. The accuracy, sensitivity, and specificity of HBcrAg with ALT in distinguishing the CHB phases were 95.65%, 95.83%, and 95.55%, respectively. Conclusion: Serum HBV RNA and HBcrAg may be useful to monitor CHB progression.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antígenos E da Hepatite B/uso terapêutico , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , DNA Viral/uso terapêutico , Antígenos do Núcleo do Vírus da Hepatite B/uso terapêutico , Biomarcadores , RNA/uso terapêutico
8.
Front Immunol ; 13: 1025654, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304473

RESUMO

Background: Hepatitis B surface antigen (HBsAg) loss is considered a functional cure for chronic hepatitis B (CHB), however, several factors influence HBsAg loss. Methods: 29 CHB patients who had achieved HBsAg loss, were selected and 58 CHB patients with persistent HBsAg were matched, according to gender and age (+/- 3 years). Logistic regression and restricted cubic spline (RCS) modelling were performed. Results: Multivariate-adjusted logistic regression, based on stepwise selection, showed that baseline HBsAg levels negatively correlated with HBsAg loss (odds ratio [OR] = 0.99, 95% confidence interval [CI] = 0.98-0.99). Interferon treatment positively related with HBsAg loss (OR = 7.99, 95%CI = 1.62-44.88). After adjusting for age, HBsAg level, ALT level, HBeAg status and interferon treatment, MMP-1 (OR = 0.66, 95%CI = 0.44-0.97), CXCL9 (OR = 0.96, 95%CI = 0.93-0.99) and TNF-R1 (OR = 0.97, 95%CI = 0.94-0.99) baseline levels all negatively correlated with HBsAg loss. Our multivariate-adjusted RCS model showed that baseline CXCL10 was associated with HBsAg loss although the relationship was "U-shaped". Conclusions: Cytokines such as MMP-1, CXCL9, CXCL10 and TNF-R1 are important factors which influence HBsAg loss. It may be possible to develop a nomogram which intercalates these factors; however, further research should consider immune processes involved in HBsAg loss.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Humanos , Receptores Tipo I de Fatores de Necrose Tumoral , Metaloproteinase 1 da Matriz , Estudos de Casos e Controles , Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Interferons/uso terapêutico , Fatores Imunológicos/uso terapêutico , China/epidemiologia
9.
BMC Surg ; 22(1): 83, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246102

RESUMO

BACKGROUND: Preoperative deep vein thrombosis (DVT) of the lower extremities delays surgery in patients with femoral shaft fractures and impairs functional recovery. However, studies on preoperative DVT in patients with femoral shaft fractures are still rare. This study was aimed to retrospectively analyze the preoperative incidence, location and risk factors associated with DVT in patients with femoral shaft fractures. METHODS: Data of patients with femoral shaft fractures and treated with surgery at the Third Hospital of Hebei Medical University were retrospectively collected from January 2013 to December 2019. The information collected included demographic data, comorbidities, injury-related data and laboratory tests. Patients were divided into DVT and non-DVT groups. Univariate and multivariate logistic regression analyses were performed to determine independent risk factors. RESULTS: A total of 432 patients were included in this study, of whom 114 (26.4%) patients were diagnosed with preoperative DVT (all asymptomatic) and injured extremities of 78.1% (89/114) were investigated. Multivariate analysis showed that older age (increase in each 10 years), delay time from injury to operation (in each day), FIB > 4 g/L were independent risk factors for preoperative DVT. CONCLUSION: Patients with femoral shaft fractures (especially the elderly and patients with the above-mentioned conditions) are at the risk of DVT right from admission to surgery hence should be intensively monitored and provided with prompt treatment to prevent DVT.


Assuntos
Fraturas do Fêmur , Trombose Venosa , Idoso , Fraturas do Fêmur/complicações , Fraturas do Fêmur/epidemiologia , Fraturas do Fêmur/cirurgia , Humanos , Incidência , Estudos Retrospectivos , Fatores de Risco , Trombose Venosa/complicações , Trombose Venosa/epidemiologia
10.
Nanoscale ; 12(28): 15275-15282, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32644059

RESUMO

Nuclear delivery of anticancer drugs, particularly dual complementary anticancer drugs, can significantly improve chemotherapy efficacy. However, successful examples are rare. We reported a novel dual anticancer drug-based nanomedicine with nuclear accumulation properties. The nanomedicine was formed by chelation between a drug peptide amphiphile Rh-GFFYERGD (Rh represents Rhein, 1,8-dihydroxy-3-carboxy anthraquinonea) and cisplatinum (Pt). A single molecule of the drug peptide amphiphile could chelate up to 8 equiv. of cisplatinum in the resulting nanofibers. The nanofibers with a 1 : 4 ratio of Rh-GFFYERGD to cisplatinum demonstrated remarkable cellular uptake, and more significantly, superior nuclear accumulation properties. Additionally, the nanofibers could also bind to the DNA molecule more efficiently than those formed by the drug peptide amphiphile. Thus the nanofibers exhibited excellent anticancer properties both in vitro and in vivo. We envision a significant therapeutic potential of the dual anticancer drug-based nanomedicine with cisplatinum in cancer.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Cisplatino , Humanos , Nanomedicina , Neoplasias/tratamento farmacológico , Peptídeos
11.
ACS Appl Mater Interfaces ; 12(20): 22492-22498, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32352747

RESUMO

Inspired by the biological process of phosphorylation for which different sites of the same protein may have different activities and functions, we utilized phosphatase-based enzyme-instructed self-assembly (EISA) to construct self-assembled nanomedicine from the precursors with different phosphorylated sites. We found that, although the obtained self-assembling molecules after EISA were identical, the changes of EISA catalytic sites could determine the outcome of molecular self-assembly. The precursor with the phosphorylated site in the middle preorganized before EISA, while the ones with other phosphorylated sites could not preorganize before EISA. After EISA, the preorganized precursor then resulted in more stable and ordered assemblies than those of the others, which showed increased cellular uptake and up to 1.7-fold higher efficacy in an antitumor therapeutic compared to those assembled from unorganized precursors.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Fosfopeptídeos/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos Endogâmicos BALB C , Nanomedicina/métodos , Oligopeptídeos/síntese química , Oligopeptídeos/toxicidade , Fosfopeptídeos/síntese química , Fosfopeptídeos/toxicidade
12.
Nanoscale ; 12(3): 2111-2117, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31913398

RESUMO

The development of molecules with immune stimulatory properties is crucial for cancer immunotherapy. In this work, we combined two peptide-based molecules, tuftsin (TKPR) and Nap-GDFDFDY, to develop a novel self-assembling molecule Nap-GDFDFDYTKPR (Comp.3), which has strong CD8+ T cell stimulatory properties. Comp.3 could self-assemble into nanofibers and hydrogels, which significantly improved the stability of tuftsin against enzyme digestion. The nanofibers of Comp.3 enhanced the phagocytic activity of macrophages, promoted the maturation of DCs, and stimulated the expression of cytokines. In addition, it demonstrated an excellent anti-tumor efficacy in vivo by eliciting a strong CD8+ T immune response. Taken together, our observations revealed a powerful immune stimulating nanomaterial that is a promising compound for cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Hidrogéis , Imunidade Celular/efeitos dos fármacos , Neoplasias Mamárias Animais , Nanofibras , Tuftsina , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Feminino , Hidrogéis/química , Hidrogéis/farmacologia , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/imunologia , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nanofibras/química , Nanofibras/uso terapêutico , Células RAW 264.7 , Tuftsina/química , Tuftsina/farmacologia
13.
J Control Release ; 317: 109-117, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31778740

RESUMO

Subcellular delivery of nanomedicines has emerged as a promising approach to enhance the therapeutic efficacy of anticancer drugs. Nuclear accumulation of anticancer drugs are essential for its therapeutic efficacy because their targets are generally located within the nucleus. However, strategies for the nuclear accumulation of nanomedicines with anticancer drugs rarely reported. In this study, we reported a promising nanomedicine, comprising a drug-peptide amphiphile, with enhanced cellular uptake and nuclear accumulation capability for cancer therapy. The drug-peptide amphiphile consisted of the peptide ligand PMI (TSFAEYWNLLSP), which was capable of activating the p53 gene by binding with the MDM2 and MDMX located in the cell nucleus. Peptide conformations could be finely tuned by using different strategies including heating-cooling and enzyme-instructed self-assembly (EISA) to trigger molecular self-assembly at different temperatures. Due to the different peptide conformations, the drug-peptide amphiphile self-assembled into nanomedicines with various properties, including stabilities, cellular uptake, and nuclear accumulation. The optimized nanomedicine formed by EISA strategy at a low temperature of 4 °C showed enhanced cellular uptake and nuclear accumulation capability, and thus exhibited superior anticancer ability both in vitro and in vivo. Overall, our study provides a useful strategy for finely tuning the properties and activities of peptide-based supramolecular nanomaterials, which may lead to optimized nanomedicines with enhanced performance.


Assuntos
Antineoplásicos , Nanoestruturas , Preparações Farmacêuticas , Nanomedicina , Peptídeos
14.
Research (Wash D C) ; 2019: 4803624, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31912037

RESUMO

The selective formation of nanomaterials in cancer cells and tumors holds great promise for cancer diagnostics and therapy. Until now, most strategies rely on a single trigger to control the formation of nanomaterials in situ. The combination of two or more triggers may provide for more sophisticated means of manipulation. In this study, we rationally designed a molecule (Comp. 1) capable of responding to two enzymes, alkaline phosphatase (ALP), and reductase. Since the A549 lung cancer cell line showed elevated levels of extracellular ALP and intracellular reductase, we demonstrated that Comp. 1 responded in a stepwise fashion to those two enzymes and displayed a tandem molecular self-assembly behavior. The selective formation of nanofibers in the mitochondria of the lung cancer cells led to the disruption of the mitochondrial membrane, resulting in an increased level of reactive oxygen species (ROS) and the release of cytochrome C (Cyt C). ROS can react with proteins, resulting in endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). This severe ER stress led to disruption of the ER, formation of vacuoles, and ultimately, apoptosis of the A549 cells. Therefore, Comp. 1 could selectively inhibit lung cancer cells in vitro and A549 xenograft tumors in vivo. Our study provides a novel strategy for the selective formation of nanomaterials in lung cancer cells, which is powerful and promising for the diagnosis and treatment of lung cancer.

15.
Nanoscale ; 10(45): 21459-21465, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30427030

RESUMO

Peptide-based supramolecular hydrogels that are stimuli-responsive under aqueous conditions have many potential biological applications, including drug delivery and sensing. Herein, we reported a series of responsive peptide-based supramolecular hydrogels that respond to glutathione (GSH), nitric oxide (NO) and hydrogen sulfide (H2S), which are biologically important signaling molecules. The responsive hydrogelators were designed by "self-immolative" chemistry and constructed by using self-immolative groups to modify short peptides. The self-immolative capping group could be removed in the presence of a corresponding trigger, thus causing gel-sol phase transitions. The potential of our responsive hydrogels for drug release was also demonstrated in this study. Our study offered several candidates of responsive hydrogels for sensing and drug delivery.

16.
Adv Healthc Mater ; 7(22): e1800899, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30302950

RESUMO

Antibody-based medicines and nanomedicines are very promising for cancer therapy due to the high specificity and efficacy of antibodies. However, antibody-drug conjugates and antibody-modified nanomaterials frequently suffer from low drug loading and loss of functions due to the covalent modification of the antibody. A novel and versatile strategy to prepare supramolecular nanomaterials by the coassembly of an affibody (antiHER2) and drug-peptide amphiphiles is reported here. During the enzyme-instructed self-assembly process, the drug-peptide amphiphile can coassemble with the affibody, resulting in supramolecular nanofibers in hydrogels. The drug loading in the supramolecular nanofibers is high (>30 wt%), and the stability of antiHER2 is significantly improved in the nanofibers at 37 °C (>15 d in vitro). The supramolecular nanofibers exhibit high affinity for HER2+ cancer cells and can be efficiently taken up by these cells. In a mouse tumor model, the supramolecular nanofibers abolish HER2+ NCI-N87 tumor growth due to the good accumulation and retention of nanofibers in tumor. This study provides a novel strategy to prepare nanomedicines with high drug loading and high specificity.


Assuntos
Antineoplásicos/química , Nanofibras/química , Peptídeos/química , Proteínas Recombinantes de Fusão/química , Sequência de Aminoácidos , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Hidrogéis/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Imagem Óptica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Transplante Heterólogo
17.
Chem Commun (Camb) ; 54(22): 2751-2754, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29479604

RESUMO

We designed and synthesized three phosphorylated peptides as precursors of the same peptide Nap-YYY. We found that different precursors led to different materials with almost identical chemical compositions at the final stages. Only Nap-YpYY could form very uniform nanofibers in a stable supramolecular hydrogel by enzyme-instructed self-assembly (EISA) at the physiological temperature (37 °C). In contrast, de-phosphorylation of the other two precursors (Nap-pYYY and Nap-YYpY) resulted in diverse nanostructures in metastable hydrogels with precipitates. The formation of uniform nanomaterials in the stable hydrogels was due to the preorganization property of the precursor Nap-YpYY, which facilitated rapid folding and accelerated the kinetics of hydrogelation of the resulting peptide Nap-YYY generated by the EISA process. Our study demonstrated the importance of the precursor for the self-assembly of nanomaterials and provided a useful strategy to manipulate them.

18.
Nanoscale ; 9(37): 14058-14064, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28895610

RESUMO

Inflammatory responses play crucial roles in the development and progression of tumors. Tumor-associated inflammation not only promotes tumor growth but also induces the suppression of immune responses against tumors. We demonstrate in this study that hydrogels of nonsteroidal anti-inflammatory drug (NSAID) modified D-tetrapeptides (GDFDFDY) are promising cancer vaccine adjuvants, especially for Fbp-gel and Car-gel. The hydrogels allow easy incorporation of a protein OVA antigen by vortexing. Our results indicate that vaccines based on Fbp-gel and Car-gel increase IgG production by 1476- and 929-fold, compared with the OVA group, respectively. They exhibit higher IgG2a antibody titers and stimulate the production of IFN-γ and IL-6 cytokines. Their higher antibody and cytokine eliciting properties in combination with their anti-inflammatory properties endow them with excellent tumor elimination properties in vivo. In a preventive immune assay against B16-OVA tumors, they totally prevent tumorigenesis. In a therapeutic immune assay against EG7-OVA tumors, they inhibit tumor growth by 75%, compared with the PBS group. Our results suggest the great potential of our hydrogels in the development of vaccines to treat cancers.


Assuntos
Adjuvantes Imunológicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Vacinas Anticâncer/farmacologia , Carcinogênese/efeitos dos fármacos , Hidrogéis , Peptídeos/farmacologia , Animais , Feminino , Humanos , Melanoma Experimental/tratamento farmacológico , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/tratamento farmacológico , Ovalbumina
19.
Nanoscale ; 9(33): 11987-11993, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28792044

RESUMO

The α-helix is the most prevalent conformation in proteins. However, formation of the α-helical conformation remains a challenge for short peptides with less than 5 amino acids. We demonstrated in this study that enzyme-instructed self-assembly (EISA) provides a unique pathway to assist the self-assembly of peptides into the α-helical conformation, while a heating-cooling process leads to a conformation more similar to a ß-sheet. The same peptide with different conformations self-assembled into different nanostructures. The peptide with α-helical conformation self-assembled into stable nanofibers and hydrogels, while the other one assembled into an unstable nanoparticle suspension. The nanofiber solution exhibited better stability against proteinase K digestion and an enhanced cellular uptake compared to the nanoparticle solution. Therefore, the nanomedicine formed by the α-helical peptide showed a better inhibition capacity against cancer cells in vitro and significantly inhibited tumor growth in vivo compared to the one formed by the ß-sheet peptide. Our study demonstrates the unique advantages of EISA to assist peptide folding and self-assembly into biofunctional nanomaterials.


Assuntos
Antineoplásicos/farmacologia , Nanofibras , Neoplasias Experimentais/tratamento farmacológico , Peptídeos/química , Dobramento de Proteína , Animais , Clorambucila/farmacologia , Endopeptidase K , Enzimas/química , Feminino , Células HeLa , Humanos , Hidrogéis , Células MCF-7 , Camundongos Endogâmicos BALB C , Estrutura Molecular , Nanoestruturas , Estrutura Secundária de Proteína
20.
J Asian Nat Prod Res ; 19(10): 987-992, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28649852

RESUMO

Two new guaiane-type sesquiterpenoids, named 4α,5α-epoxy-8ß-hydroxy-1α-hydro-α-guaiene (1) and 4α,5α-epoxy-1-hydroxy-α-guaiene (2), were isolated from the whole plants of Valeriana hardwickii. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 1 and 2 showed weak cytotoxicity against the lung adenocarcinoma (A549) and hepatoma (Bel7402) cell lines with IC50 values of 9.2 and 8.5 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Sesquiterpenos de Guaiano/isolamento & purificação , Valeriana/química , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Azulenos , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Paclitaxel/farmacologia , Sesquiterpenos de Guaiano/química , Sesquiterpenos de Guaiano/farmacologia
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