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1.
Poult Sci ; 103(6): 103648, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38574460

RESUMO

Avian infectious bronchitis virus (IBV) still causes serious economic losses in the poultry industry. Currently, there are multiple prevalent genotypes and serotypes of IBVs. It is imperative to develop a new diagnosis method that is fast, sensitive, specific, simple, and broad-spectrum. A monoclonal hybridoma cell, N2D5, against the IBV N protein was obtained after fusion of myeloma SP2/0 cells with spleen cells isolated from the immunized Balb/c mice. The N2D5 monoclonal antibody (mAb) and the previously prepared mouse polyclonal antibody against the IBV N protein were used to target IBV as a colloidal gold-mAb conjugate and a captured antibody, respectively, in order to develop an immunochromatographic strip. The optimal pH and minimum antibody concentration in the reaction system for colloidal gold-mAb N2D5 conjugation were pH 6.5 and 30 µg/mL, respectively. Common avian pathogens were tested to evaluate the specificity of the strip and no cross-reaction was observed. The sensitivity of the strip for detecting IBV was 10-1.4522 EID50/mL. The strip showed a broad-spectrum cross-reactive capacity for detecting IBV antigens, including multiple IBV genotypes in China and all of the seven serotypes of IBV that are currently prevalent in southern China. Additionally, the result can be observed within 2 min without any equipment. The throat and cloacal swab samples of chickens that were artificially infected with three IBV strains were tested using the developed strip and the qPCR method; the strip test demonstrated a high consistency in detecting IBV via qPCR gene detection. In conclusion, the immunochromatographic strip that was established is rapid, sensitive, specific, simple, practical, and broad-spectrum; additionally, it has the potential to serve as an on-site rapid detection method of IBV and can facilitate the surveillance and control of the disease, especially in resource-limited areas.


Assuntos
Anticorpos Monoclonais , Galinhas , Infecções por Coronavirus , Coloide de Ouro , Vírus da Bronquite Infecciosa , Camundongos Endogâmicos BALB C , Doenças das Aves Domésticas , Vírus da Bronquite Infecciosa/isolamento & purificação , Vírus da Bronquite Infecciosa/imunologia , Animais , Coloide de Ouro/química , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/virologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade/veterinária , Cromatografia de Afinidade/métodos , Camundongos , Sensibilidade e Especificidade , Fitas Reagentes
2.
Elife ; 122024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578670

RESUMO

P2X receptors are extracellular ATP-gated ion channels that form homo- or heterotrimers and consist of seven subtypes. They are expressed in various tissues, including neuronal and nonneuronal cells, and play critical roles in physiological processes such as neurotransmission, inflammation, pain, and cancer. As a result, P2X receptors have attracted considerable interest as drug targets, and various competitive inhibitors have been developed. However, although several P2X receptor structures from different subtypes have been reported, the limited structural information of P2X receptors in complex with competitive antagonists hampers the understanding of orthosteric inhibition, hindering the further design and optimization of those antagonists for drug discovery. We determined the cryogenic electron microscopy (cryo-EM) structures of the mammalian P2X7 receptor in complex with two classical competitive antagonists of pyridoxal-5'-phosphate derivatives, pyridoxal-5'-phosphate-6-(2'-naphthylazo-6'-nitro-4',8'-disulfonate) (PPNDS) and pyridoxal phosphate-6-azophenyl-2',5'-disulfonic acid (PPADS), and performed structure-based mutational analysis by patch-clamp recording as well as molecular dynamics (MD) simulations. Our structures revealed the orthosteric site for PPADS/PPNDS, and structural comparison with the previously reported apo- and ATP-bound structures showed how PPADS/PPNDS binding inhibits the conformational changes associated with channel activation. In addition, structure-based mutational analysis identified key residues involved in the PPNDS sensitivity of P2X1 and P2X3, which are known to have higher affinity for PPADS/PPNDS than other P2X subtypes.


Assuntos
Trifosfato de Adenosina , Simulação de Dinâmica Molecular , Animais , Trifosfato de Adenosina/química , Mamíferos
3.
Nat Commun ; 14(1): 5844, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730705

RESUMO

P2X receptors are cation channels that sense extracellular ATP. Many therapeutic candidates targeting P2X receptors have begun clinical trials or acquired approval for the treatment of refractory chronic cough (RCC) and other disorders. However, the present negative allosteric modulation of P2X receptors is primarily limited to the central pocket or the site below the left flipper domain. Here, we uncover a mechanism of allosteric regulation of P2X3 in the inner pocket of the head domain (IP-HD), and show that the antitussive effects of quercetin and PSFL2915 (our nM-affinity P2X3 inhibitor optimized based on quercetin) on male mice and guinea pigs were achieved by preventing allosteric changes of IP-HD in P2X3. While being therapeutically comparable to the newly licensed P2X3 RCC drug gefapixant, quercetin and PSFL2915 do not have an adverse effect on taste as gefapixant does. Thus, allosteric modulation of P2X3 via IP-HD may be a druggable strategy to alleviate RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Masculino , Animais , Cobaias , Camundongos , Tosse/tratamento farmacológico , Quercetina/farmacologia , Quercetina/uso terapêutico , Paladar
4.
Front Endocrinol (Lausanne) ; 14: 920548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36824359

RESUMO

Background: ISL LIM homeobox 2, also known as insulin gene enhancer protein ISL-2 (ISL2), is a transcription factor gene that participates in a wide range of developmental events. However, the role of ISL2 in the hypothalamus-pituitary-thyroid axis is largely unknown. In the present study, we characterized the expression patterns of ISL2 and revealed its regulative role during embryogenesis using zebrafish. Methods: We used the CRISPR/Cas9 system to successfully establish homozygous ISL2-orthologue (isl2a and isl2b) knockout zebrafish. Moreover, we utilized these knockout zebrafish to analyze the pituitary and thyroid phenotypes in vivo. For further molecular characterization, in situ hybridization and immunofluorescence were performed. Results: The isl2a mutant zebrafish presented with thyroid hypoplasia, reduced whole-body levels of thyroid hormones, increased early mortality, gender imbalance, and morphological retardation during maturity. Additionally, thyrotropes, a pituitary cell type, was notably decreased during development. Importantly, the transcriptional levels of pituitary-thyroid axis hormones-encoding genes, such as tshba, cga, and tg, were significantly decreased in isl2a mutants. Finally, the thyroid dysplasia in isl2a mutant larvae may be attributed to a reduction in proliferation rather than changes in apoptosis. Conclusions: In summary, isl2a regulates the transcriptional levels of marker genes in hypothalamus-pituitary-thyroid axis, and isl2a knockout causing low thyroid hormone levels in zebrafish. Thus, isl2a identified by the present study, is a novel regulator for pituitary cell differentiation in zebrafish, resulting in thyroid gland hypoplasia and phenotypes of hypothyroidism.


Assuntos
Fatores de Transcrição , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Hipófise/metabolismo , Hormônios Tireóideos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
5.
Pain Res Manag ; 2022: 3458056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711611

RESUMO

Background: The enhanced recovery after surgery (ERAS) program is aimed to shorten patients' recovery process and improve clinical outcomes. This study aimed to compare the outcomes between the ERAS program and the traditional pathway among patients with ankle fracture and distal radius fracture. Methods: This is a multicenter prospective clinical controlled study consisting of 323 consecutive adults with ankle fracture from 12 centers and 323 consecutive adults with distal radial fracture from 13 centers scheduled for open reduction and internal fixation between January 2017 and December 2018. According to the perioperative protocol, patients were divided into two groups: the ERAS group and the traditional group. The primary outcome was the patients' satisfaction of the whole treatment on discharge and at 6 months postoperatively. The secondary outcomes include delapsed time between admission and surgery, length of hospital stay, postoperative complications, functional score, and the MOS item short form health survey-36. Results: Data describing 772 patients with ankle fracture and 658 patients with distal radius fracture were collected, of which 323 patients with ankle fracture and 323 patients with distal radial fracture were included for analysis. The patients in the ERAS group showed higher satisfaction levels on discharge and at 6 months postoperatively than in the traditional group (P < 0.001). In the subgroup analysis, patients with distal radial fracture in the ERAS group were more satisfied with the treatment (P=0.001). Furthermore, patients with ankle fracture had less time in bed (P < 0.001) and shorter hospital stay (P < 0.001) and patients with distal radial fracture received surgery quickly after being admitted into the ward in the ERAS group than in the traditional group (P=0.001). Conclusions: Perioperative protocol based on the ERAS program was associated with high satisfaction levels, less time in bed, and short hospital stay without increased complication rate and decreased functional outcomes.


Assuntos
Fraturas do Tornozelo , Recuperação Pós-Cirúrgica Melhorada , Fraturas do Rádio , Adulto , Fraturas do Tornozelo/cirurgia , Humanos , Tempo de Internação , Estudos Prospectivos , Fraturas do Rádio/cirurgia , Resultado do Tratamento
6.
J Biol Chem ; 298(6): 102002, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35504351

RESUMO

P2X receptors are a class of nonselective cation channels widely distributed in the immune and nervous systems, and their dysfunction is a significant cause of tumors, inflammation, leukemia, and immune diseases. P2X7 is a unique member of the P2X receptor family with many properties that differ from other subtypes in terms of primary sequence, the architecture of N- and C-terminals, and channel function. Here, we suggest that the observed lengthened ß2- and ß3-sheets and their linker (loop ß2,3), encoded by redundant sequences, play an indispensable role in the activation of the P2X7 receptor. We show that deletion of this longer structural element leads to the loss of P2X7 function. Furthermore, by combining mutagenesis, chimera construction, surface expression, and protein stability analysis, we found that the deletion of the longer ß2,3-loop affects P2X7 surface expression but, more importantly, that this loop affects channel gating of P2X7. We propose that the longer ß2,3-sheets may have a negative regulatory effect on a loop on the head domain and on the structural element formed by E171 and its surrounding regions. Understanding the role of the unique structure of the P2X7 receptor in the gating process will aid in the development of selective drugs targeting this subtype.


Assuntos
Trifosfato de Adenosina , Conformação Proteica em Folha beta , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina/metabolismo , Humanos , Inflamação , Conformação Proteica em Folha beta/genética , Estabilidade Proteica , Receptores Purinérgicos P2X7/química , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Ativação Transcricional
7.
Front Pharmacol ; 13: 779715, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242031

RESUMO

Thymopentin (TP5) is an immunomodulatory pentapeptide that has been widely used in malignancy patients with immunodeficiency due to radiotherapy and chemotherapy. Here, we propose that TP5 directly inhibits the stemness of colon cancer cells HCT116 and therefore enhances the cytotoxicity of oxaliplatin (OXA) in HCT116 cells. In the absence of serum, TP5 was able to induce cancer stemness reduction in cultured HCT116 cells and significantly reduced stemness-related signals, such as the expression of surface molecular markers (CD133, CD44 and CD24) and stemness-related genes (ALDH1, SOX2, Oct-4 and Nanog), and resulted in altered Wnt/ß-catenin signaling. Acetylcholine receptors (AchRs) are implicated in this process. OXA is a common chemotherapeutic agent with therapeutic effects in various cancers. Although TP5 had no direct effect on the proliferation of HCT116, this pentapeptide significantly increased the sensitivity of HCT116 to OXA, where the effect of TP5 on the stemness of colon cancer cells through stimulation of AchRs may contribute to this process. Our results provide a promising strategy for increasing the sensitivity of colon cancer cells to chemotherapeutic agents by incorporating immunomodulatory peptides.

8.
Biomicrofluidics ; 15(2): 024110, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33868537

RESUMO

As the heavy metal contamination is becoming worse, monitoring the heavy metal content in water or human body gets more and more important. In this research, a cadmium ion-selective field effect transistor (Cd-ISFET) for rapidly detecting cadmium ions has been developed and the mechanism of the sensor is also investigated in depth. Our Cd-ISFET sensor exhibits high sensitivity beyond the ideal Nernst sensitivity, wide dynamic range, low detection limit (∼10-11M), which is comparable with inductively coupled plasma mass spectrometry, and easy operation enabling people to detect cadmium ion by themselves. From the analysis of electrical measurement results, this Cd-ISFET is preferred to operate at the bias with the maximum transconductance of the FET to enhance the sensor signal. The AC impedance measurement is carried out to directly investigate the mechanism of an ion-selective membrane (ISM). From impedance results, the real part of the total impedance, which is the resistance, was shown to dominate the sensor signal. The potential drop across the ISM is caused by the heavy metal ion in the membrane, which is employed to the gate of the FET via an extended gate electrode. Cadmium ion detection in one drop of human serum with this sensor was demonstrated. This cost-effective and highly sensitive sensor is promising and can be used by anyone and anywhere to prevent people from cadmium poisoning.

9.
J Biol Chem ; 296: 100655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901491

RESUMO

Highly conserved amino acids are generally anticipated to have similar functions across a protein superfamily, including that of the P2X ion channels, which are gated by extracellular ATP. However, whether and how these functions are conserved becomes less clear when neighboring amino acids are not conserved. Here, we investigate one such case, focused on the highly conserved residue from P2X4, E118 (rat P2X4 numbering, rP2X4), a P2X subtype associated with human neuropathic pain. When we compared the crystal structures of P2X4 with those of other P2X subtypes, including P2X3, P2X7, and AmP2X, we observed a slightly altered side-chain orientation of E118. We used protein chimeras, double-mutant cycle analysis, and molecular modeling to reveal that E118 forms specific contacts with amino acids in the "beak" region, which facilitates ATP binding to rP2X4. These contacts are not present in other subtypes because of sequence variance in the beak region, resulting in decoupling of this conserved residue from ATP recognition and/or channel gating of P2X receptors. Our study provides an example of a conserved residue with a specific role in functional proteins enabled by adjacent nonconserved residues. The unique role established by the E118-beak region contact provides a blueprint for the development of subtype-specific inhibitors of P2X4.


Assuntos
Trifosfato de Adenosina/metabolismo , Ativação do Canal Iônico , Receptores Purinérgicos P2X4/metabolismo , Sequência de Aminoácidos , Animais , Eletrofisiologia , Células HEK293 , Humanos , Modelos Moleculares , Conformação Proteica , Homologia de Sequência , Peixe-Zebra
10.
Int J Nanomedicine ; 15: 513-519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099353

RESUMO

BACKGROUND: In recent years, numerous bacteria have become resistant to conventional antibiotics. Fortunately, an increasing body of research indicates that through the addition of specific metabolites (like sugars), the antibacterial activity of certain drugs can be enhanced. A new type of self-assembled nano-peptide amphiphile (SANPA) was designed in this study to treat antibiotic-resistant bacterial infections and to reduce the use of antibiotics. METHODS: Here, SANPAs were self-assembled into nanorod structures with a diameter of ca. 10.5 nm at concentrations greater than the critical micelle concentration (CMC) of 44.67 µM. Both Gram-positive and Gram-negative bacteria were treated with SANPAs with fructose supplementation. RESULTS: After a 30-min fructose pre-incubation, SANPAs reduced bacteria growth relative to non-fructose treatments at all concentrations. Cytotoxicity assays indicated that the presence of fructose seemed to slightly ameliorate the cytotoxic effect of the treatment on model human fetal osteoblasts (or bone-forming cells) and human dermal fibroblasts. CONCLUSION: We demonstrated here that SANPAs-like nanomaterials have a promising potential to treat antibiotic-resistant bacteria, especially when added to fructose, potentially limiting their associated infections.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Frutose/farmacologia , Peptídeos/química , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Células Cultivadas , Escherichia coli/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Frutose/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanoestruturas/química , Peptídeos/farmacologia
11.
J Biol Chem ; 294(51): 19589-19603, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31727741

RESUMO

Although the extracellular ATP-gated cation channel purinergic receptor P2X5 is widely expressed in heart, skeletal muscle, and immune and nervous systems in mammals, little is known about its functions and channel-gating activities. This lack of knowledge is due to P2X5's weak ATP responses in several mammalian species, such as humans, rats, and mice. WT human P2X5 (hP2X5Δ328-349) does not respond to ATP, whereas a full-length variant, hP2X5 (hP2X5-FL), containing exon 10 encoding the second hP2X5 transmembrane domain (TM2), does. However, although rat P2X5 (rP2X5) has a full-length TM2, ATP induces only weak currents in rP2X5, which prompted us to investigate the mechanism underlying this small ATP response. Here, we show that single replacements of specific rP2X5 residues with the corresponding residues in hP2X5 (S191F or F195H) significantly enhance the current amplitude of rP2X5. Using a combination of engineered disulfide cross-linking, single-channel recording, and molecular modeling, we interrogated the effects of S191F and F195H substitutions on the allostery of the left flipper (LF) domain. On the basis of our findings, we propose that the bound ATP-induced distinct allostery of the LF domain with that of other functional subtypes has caused the weak ATP response of rP2X5 receptors. The findings of our study provide the prerequisite for future transgenic studies on the physiological and pathological functions of P2X5 receptors.


Assuntos
Trifosfato de Adenosina/química , Receptores Purinérgicos P2X5/química , Sítio Alostérico , Animais , Biotinilação , Cátions , Reagentes de Ligações Cruzadas , Dissulfetos/química , Éxons , Células HEK293 , Humanos , Simulação de Dinâmica Molecular , Domínios Proteicos , Ratos , Proteínas Recombinantes de Fusão/química
12.
Int J Nanomedicine ; 14: 3265-3272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118634

RESUMO

BACKGROUND: In vitro and in vivo studies have shown that metallic implants coated with nano hydroxyapatite (HA) reduce the time needed for complete osseointegration compared to metallic implants coated with conventional or micron-sized HA. Moreover, due to their biologically inspired nanometer dimensions, amphiphilic peptide nanoparticles (APNPs) can also promote osteoblast attachment and enhance other cell functions if used as a coating material. Coatings made of HA and APNPs could improve osteoblast functions, but have never been tested. PURPOSE: The objective of this study was to prepare coatings of nanocrystalline HA and APNPs on poly(2-hydroxyethyl methacrylate) (pHEMA) coatings in order to improve osteoblast (bone-forming cells) adhesion and cell density. METHODS: HA was synthesized by a wet chemical process. Coatings were synthesized with different conditions and components. RESULTS: X-ray diffraction infrared spectroscopy, transmission electron microscopy, and electron diffraction showed that nanocrystalline HA was synthesized with an expected nano size and shape distribution but with low impurities. pHEMA hydrogels with HA and APNPs increased osteoblast densities after 3 days compared to controls. CONCLUSION: Since cell proliferation is a prerequisite function for bone formation, these results imply that the current materials should be tested for a wide range of orthopedic applications.


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Nanopartículas/química , Osteoblastos/citologia , Peptídeos/química , Tensoativos/química , Contagem de Células , Humanos , Nanopartículas/ultraestrutura , Difração de Raios X
13.
Biomater Sci ; 7(6): 2430-2439, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30933194

RESUMO

Coaxial electrospinning is a novel technique for producing core-shell nanofibers that provide a robust structure and deliver hydrophilic bioactive agents. Optimization of parameters used in the coaxial electrospinning process allows for the fabrication of uniform and bead-free polyvinyl alcohol (PVA)/poly (l-lactic acid) (PLLA) core-shell nanofibers. Herein, a cold atmospheric plasma (CAP) process was used to enhance the surface features of electrospun core-shell nanofibers for increased surface pore size and altered surface hydrophilicity. After CAP treatment, the scaffolds' water contact angle was reduced from 110° to 50° and its protein and water adsorption were significantly elevated. The changes in hydrophilicity and improved scaffold surface area dramatically enhanced cell attachment and proliferation of fibroblasts and osteoblasts. Also, the increased levels of alkaline phosphatase (ALP) activity, total protein content and calcium deposition from mesenchymal stem cells (MSCs) indicated a higher osteoinductivity of the CAP-modified nanofibrous scaffold. Most importantly, the increased nanofiber surface pore size induced by the CAP treatment further contributed to significant variations in drug release profiles. The CAP-treated scaffolds showed more rapid release kinetics compared to untreated scaffolds, which eventually led to complete drug release. These results indicated that the CAP-treated and bioactive protein-loaded core-shell nanofibers could be a valuable regenerative medicine and drug delivery system for improved bone tissue engineering.


Assuntos
Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Nanofibras/química , Gases em Plasma/química , Soroalbumina Bovina/química , Engenharia Tecidual , Fosfatase Alcalina/metabolismo , Animais , Cálcio/metabolismo , Bovinos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Poliésteres/química , Álcool de Polivinil/química , Soroalbumina Bovina/farmacologia , Alicerces Teciduais/química , Água/química
14.
Comput Biol Chem ; 78: 460-467, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30528728

RESUMO

BACKGROUND: Identification of potential drug-target interaction pairs is very important for pharmaceutical innovation and drug discovery. Numerous machine learning-based and network-based algorithms have been developed for predicting drug-target interactions. However, large-scale pharmacological, genomic and chemical datum emerged recently provide new opportunity for further heightening the accuracy of drug-target interactions prediction. RESULTS: In this work, based on the assumption that similar drugs tend to interact with similar proteins and vice versa, we developed a novel computational method (namely MKLC-BiRW) to predict new drug-target interactions. MKLC-BiRW integrates diverse drug-related and target-related heterogeneous information source by using the multiple kernel learning and clustering methods to generate the drug and target similarity matrices, in which the low similarity elements are set to zero to build the drug and target similarity correction networks. By incorporating these drug and target similarity correction networks with known drug-target interaction bipartite graph, MKLC-BiRW constructs the heterogeneous network on which Bi-random walk algorithm is adopted to infer the potential drug-target interactions. CONCLUSIONS: Compared with other existing state-of-the-art methods, MKLC-BiRW achieves the best performance in terms of AUC and AUPR. MKLC-BiRW can effectively predict the potential drug-target interactions.


Assuntos
Algoritmos , Análise por Conglomerados , Biologia Computacional , Aprendizado de Máquina , Terapia de Alvo Molecular , Neoplasias/dietoterapia , Neoplasias/metabolismo , Humanos , Ligação Proteica
15.
Int J Nanomedicine ; 13: 6199-6205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349244

RESUMO

BACKGROUND: In nanomedicine, gold nanoparticles (AuNPs) have demonstrated versatile therapeutic efficiencies and, in particular, have been developed for the treatment of various cancers due to their high selectivity in killing cancer, not healthy, cells. METHODS: In this study, AuNPs were conjugated with the cell-penetrating peptide Cys-(Arg)8-Asp-Ser (CRRRRRRRRGDS) by direct cross-linking of the cysteine's thiol group to the gold surface and a fibronectin-derived RGD group was also used due to its efficacy toward cancer cell targeting and possible promotion of healthy fibroblast functions. RESULTS: Ultraviolet-visible absorbance spectrum and transmission electron microscope images of the synthesized peptide-capped AuNPs (PEP-AuNPs) validated the formation of AuNP aggregates. The presence of peptides on AuNPs was confirmed by Fourier transform infrared spectroscopy and quantified by a bicinchoninic acid assay. After being modified with the arginine-rich peptide, the AuNPs possessed a positive charge, as their zeta potential increased from -23.81±8.43 mV to 8 mV on average. In this manner, an easy method to conjugate AuNPs was shown here. Further, MTS assays were performed using healthy human dermal fibroblasts. After 24 hours of treatment with PEP-AuNPs, the cell density increased dramatically to around 25,000 cells/cm2. Results further showed a very high half-maximal inhibitory concentration of 69.2 µM for the PEP-AuNPs (indicating low toxicity). CONCLUSION: The results showed for the first time the ability of PEP-AuNPs to promote human dermal fibroblast cell viability, which after further investigation, may show an ability to replace cancerous tissue with healthy soft tissue.


Assuntos
Peptídeos Penetradores de Células/síntese química , Ouro/química , Nanopartículas Metálicas/química , Sequência de Aminoácidos , Contagem de Células , Peptídeos Penetradores de Células/química , Derme/citologia , Fibroblastos/citologia , Humanos , Nanopartículas Metálicas/ultraestrutura , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Biomed Nanotechnol ; 14(5): 987-993, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29883568

RESUMO

Hydrogelators are crosslinked polymeric networks that are capable of holding large amounts of water by surface tension. High-water absorption capacity makes hydrogels readily biocompatible and, thus, more attractive for medical applications. The objective of the present in vitro study was to test supramolecular hydrogelators for multiple biomedical applications: bacterial- and cancer-related diseases. Four naphthalene-tripeptides and their D-enantiomers were synthesized using an Fmoc Solid Phase Peptide Synthesis strategy and were tested for their activity on normal and cancer cells as well as bacteria. Here, the D-enantiomer of alanine containing tripeptides at a concentration of 0.25 wt% inhibited the growth of Staphylococcus epidermidis. Moreover, cytotoxicity assays showed that naphthalene containing tripeptides possessing α-aminoisobutyric acid (Aib, U) between the two phenylalanine groups (i.e., NapFUF) selectively decreased against melanoma cancer cell viability at 0.25 wt% compared to controls (no additives) over a 24 h time period. These results suggest, for the first time, that naphthalene-tripeptides containing α-aminoisobutyric acid or alanine have numerous potential uses for diverse medical applications, in particular for fighting cancer and bacterial infections.


Assuntos
Peptídeos/química , Aminoácidos , Anti-Infecciosos , Antineoplásicos
17.
ACS Appl Mater Interfaces ; 9(27): 22350-22360, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28628296

RESUMO

The emergence of antibiotic resistance in bacteria has caused many healthcare problems and social burdens. In this study, a type of self-assembled peptide amphiphiles (PA) functionalized with a heparin-binding Cardin-motif peptide (sequence (AKKARK)2) has been designed to combat bacterial drug resistance. Above the critical micelle concentration (CMC) at 45 µM, these amphiphilic Cardin antimicrobial peptide (ACA-PA) can self-assemble into cylindrical supramolecular structures (7-10 nm in diameter) via hydrophobic interactions and ß-sheet secondary conformation. The ACA-PA displays excellent antibacterial properties against both Gram-positive and Gram-negative bacteria. This work also demonstrates the effects of molecular self-assembly on antibacterial activity of peptide amphiphiles. The ACA-PA exhibits antibacterial activity on Gram-positive bacteria in a dose-dependent manner, but in the case of Gram-negative bacteria, the antibacterial potency of ACA-PA is remarkably enhanced at concentrations above the CMC. The ACA-PA has been shown to cause bacterial cytoplasmic leakage, causing localized membrane disruption in Gram-positive bacteria and blisters on disorganized membranes of Gram-negative bacteria. Therefore, these peptide-based nanoparticles have promising potential as antimicrobial agents without resorting to the use of antibiotics, and, thus, should be further studied for a wide range of biomaterial applications.


Assuntos
Antibacterianos/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Heparina , Testes de Sensibilidade Microbiana , Peptídeos
18.
Biomed Pharmacother ; 91: 138-146, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28456113

RESUMO

To elucidate the increasing dissolution and enhancement mechanism of wine-processed Radix Scutellaria (RS) by fractal theory in nitroglycerin (NTG)-induced migraine rats. We prepared three RS from the process with 10% (S1), 15% (S2), 20% (S3) (v/m) rice wine. Mercury intrusion porosimetry and scanning electron microscope were employed to explore the internal structure of RS and the components dissolution of RS was analyzed by HPLC. Rats were randomly allocated into following groups and orally given different solutions for 10days: normal group (NOR, normal saline), model group (MOD, normal saline), Tianshu capsule group (TSC, 0.425mg/kg), ibuprofen group (IBU, 0.0821mg/kg), crude RS group (CRU, 1.04mg/kg) and wine-processed RS group (WP, 1.04mg/kg) followed by bolus subcutaneously injection of NTG (10mg/kg) to induce migraine model except NOR. Biochemical indexes (nitric oxide-NO, calcitonin-gene-related peptide-CGRP, and endothelin-ET) and c-fos positive cells were measured with commercial kits and immunohistochemical method, separately. Total surface area significantly increased in wine-processed RS (p<0.05) while fractal dimension markedly decreased (p<0.05) compared with crude RS. Additionally, S3 owned the highest increase of dissolution including the percentage increase of total extract, total flavonoids and main compounds (all p<0.05 vs S1 and S2). Pharmacodynamic data showed c-fos positive cells significantly decreased (p<0.05) in WP compared with MOD and the level of NO, CGRP, ET in WP was better than that of CRU. Wine-processed RS could be a promising candidate medicine for migraine treatment due to its increased component dissolution.


Assuntos
Transtornos de Enxaqueca/induzido quimicamente , Transtornos de Enxaqueca/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Scutellaria/química , Vinho , Animais , Comportamento Animal , Fractais , Masculino , Transtornos de Enxaqueca/sangue , Nitroglicerina , Extratos Vegetais/química , Porosidade , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Sprague-Dawley , Solubilidade
19.
Biomed Pharmacother ; 90: 116-121, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28343071

RESUMO

BACKGROUND: Migraine is a complex nervous system disease characterized by typical throbbing and unilateral headache, which causes severe healthy and social issues worldwide. The purpose of this study was to investigate the effect of baicalein (BAI) on the treatment of migraine. MATERIAL AND METHODS: Twenty-four rats were randomly divided equally into four groups, including a blank group, model group, positive group (ibuprofen tablets 82mg/kg), and BAI group (60mg/kg). All rats were intragastrically treated with the corresponding treatment for 10 consecutive days, and they were subcutaneously injected with NTG (10mg/kg) 1h after the last treatment, except in the blank group. After model establishment, the behaviors of all rats, including scratching head and shaking body were observed continuously for 100min. Four hours after NTG treatment, all rats were anaesthetized and the blood was collected. Thereafter, nitric oxide (NO) in plasma was determined by colorimetric method, the level of calcitonin gene-related peptide (CGRP) and endothelin (ET) were detected by radioimmunoassay method. In addition, immunohistochemistry was applied to detect c-Fos neuronal activity in trigeminal nucleus caudalis (TNC). RESULTS: Behavioral research showed that BAI administration alleviated the hyperalgesia in migraine rats. Compared with the model group, the levels of NO and CGRP in BAI administration groups were markedly decreased (p<0.01), and the levels of ET was significantly increased (p<0.01). Meanwhile, immunohistochemistry results showed that NTG treatment significantly activated c-Fos neurons while BAI treatment inhibited the expression of c-Fos. CONCLUSIONS: BAI could alleviate the migraine-like headache induced by NTG, which is related to the regulation of vasoactive substances. These findings may contribute to the further study of BAI as a potential drug for migraine pharmacotherapy.


Assuntos
Flavanonas/farmacologia , Transtornos de Enxaqueca/induzido quimicamente , Transtornos de Enxaqueca/tratamento farmacológico , Nitroglicerina/farmacologia , Analgesia/métodos , Animais , Peptídeo Relacionado com Gene de Calcitonina/sangue , Modelos Animais de Doenças , Endotelinas/sangue , Hiperalgesia/sangue , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Masculino , Transtornos de Enxaqueca/sangue , Transtornos de Enxaqueca/metabolismo , Óxido Nítrico/sangue , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Núcleos do Trigêmeo/efeitos dos fármacos , Núcleos do Trigêmeo/metabolismo
20.
Mol Med Rep ; 14(1): 491-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27175745

RESUMO

Mahonia bealei is a Chinese folk medicine used to treat various ailments, in particular gastrointestinal inflammation­related illnesses, and palmatine is one of its active constituents. In this study, ApcMin/+ mice, a genetically engineered model, were used to investigate the effects of palmatine on the initiation and progression of gut inflammation and tumorigenesis enhanced by a high­fat diet. The in vitro antiproliferation and anti­inflammation effects of palmatine were evaluated on HT­29 and SW­480 human colorectal cancer cell lines. The concentration­related antiproliferative effects of palmatine on both cell lines (P<0.01) were observed. Palmatine significantly inhibited lipopolysaccharide­induced increase in cytokine interleukin (IL)­8 levels in the HT­29 cells (P<0.01). In the in vivo studies with ApcMin/+ mice, after 10 or 20 mg/kg/day oral palmatine treatment, tumor numbers were significantly reduced in the small intestine and colon in a dose­dependent manner (P<0.01 compared with the model group). The results were supported by tumor distribution data, body weight changes and organ index. The effect on survival was also dose­dependent. Both the low­ and high­dose palmatine treatments significantly increased the life span of the mice (P<0.01). The gut histology from the model group showed a prominent adenomatous change along with inflammatory lesions. With palmatine treatment, however, the dysplastic changes were greatly reduced in the small intestine and colon tissue. Reverse transcription­quantitative polymerase chain reaction analysis of interleukin (IL)­1α, IL1­ß, IL­8, granulocyte­colony stimulating factor and granulocyte macrophage colony­stimulating factor in the gut tissue showed that these inflammatory cytokines were reduced significantly following treatment (all P<0.01); serum cytokine levels were also decreased. Data suggests that palmatine has a clinical value in colorectal cancer therapeutics, and this action is likely linked to the inhibition of inflammatory cytokines.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Alcaloides de Berberina/farmacologia , Citocinas/metabolismo , Neoplasias Gastrointestinais/etiologia , Neoplasias Gastrointestinais/metabolismo , Mediadores da Inflamação/metabolismo , Mahonia/química , Extratos Vegetais/farmacologia , Proteína da Polipose Adenomatosa do Colo/sangue , Animais , Alcaloides de Berberina/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocinas/sangue , Modelos Animais de Doenças , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Masculino , Camundongos , Camundongos Knockout , Extratos Vegetais/química , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
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