Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.041
Filtrar
1.
J Vis Exp ; (162)2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32831304

RESUMO

Several negatively charged tissues in the body, like cartilage, present a barrier to the targeted drug delivery due to their high density of negatively charged aggrecans and, therefore, require improved targeting methods to increase their therapeutic response. Because cartilage has a high negative fixed charge density, drugs can be modified with positively charged drug carriers to take advantage of electrostatic interactions, allowing for enhanced intra-cartilage drug transport. Studying the transport of drug carriers is, therefore, crucial towards predicting the efficacy of drugs in inducing a biological response. We show the design of three experiments which can quantify the equilibrium uptake, depth of penetration and non-equilibrium diffusion rate of cationic peptide carriers in cartilage explants. Equilibrium uptake experiments provide a measure of the solute concentration within the cartilage compared to its surrounding bath, which is useful for predicting the potential of a drug carrier in enhancing therapeutic concentration of drugs in cartilage. Depth of penetration studies using confocal microscopy allow for the visual representation of 1D solute diffusion from the superficial to deep zone of cartilage, which is important for assessing whether solutes reach their matrix and cellular target sites. Non-equilibrium diffusion rate studies using a custom-designed transport chamber enables the measurement of the strength of binding interactions with the tissue matrix by characterizing the diffusion rates of fluorescently labeled solutes across the tissue; this is beneficial for designing carriers of optimal binding strength with cartilage. Together, the results obtained from the three transport experiments provide a guideline for designing optimally charged drug carriers which take advantage of weak and reversible charge interactions for drug delivery applications. These experimental methods can also be applied to evaluate the transport of drugs and drug-drug carrier conjugates. Further, these methods can be adapted for the use in targeting other negatively charged tissues such as meniscus, cornea and the vitreous humor.


Assuntos
Cartilagem/metabolismo , Portadores de Fármacos/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Peptídeos/farmacocinética , Animais , Cartilagem/efeitos dos fármacos , Cátions/química , Difusão , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Peptídeos/administração & dosagem , Peptídeos/química , Eletricidade Estática
2.
Adv Exp Med Biol ; 1250: 35-48, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32601936

RESUMO

Injectable in situ-forming hydrogels have been used clinically in diverse biomedical applications. These hydrogels have distinct advantages such as easy management and minimal invasiveness. The hydrogels are aqueous formulations, and a simple injection at the target site replaces a traditional surgical procedure. Here, we review injectable in situ-forming hydrogels that are formulated by physical and chemical methods to deliver proteins and peptides. Prospects for using in situ-forming hydrogels for several specific applications are also discussed.


Assuntos
Hidrogéis , Peptídeos , Proteínas , Sistemas de Liberação de Medicamentos , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/química , Injeções , Peptídeos/administração & dosagem , Proteínas/administração & dosagem
3.
J Vis Exp ; (160)2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32597836

RESUMO

Since the initial description of protein transduction domains, also known as cell penetrating peptides, over 25 years ago, there has been intense interest in developing these peptides, especially cell-specific ones, as novel vectors for delivering diagnostic and therapeutic materials. Our past work involving phage display identified a novel, nonnaturally occurring, 12 amino acid-long peptide that we named cardiac targeting peptide (CTP) due to its ability to transduce normal heart tissue in vivo with peak uptake seen in as little as 15 min after an intravenous injection. We have undertaken detailed biodistribution studies by injecting CTP labeled with fluorophore cyanine5.5, allowing it to circulate for various periods of time, and euthanizing, fixing, and sectioning multiple organs followed by fluorescent microscopy imaging. In this publication, we describe these processes as well as ex vivo imaging of harvested organs using an in vivo imaging system in detail. We provide detailed methodologies and practices for undertaking transduction as well as biodistribution studies using CTP as an example.


Assuntos
Imageamento Tridimensional , Miocárdio/metabolismo , Peptídeos/metabolismo , Transdução Genética , Animais , Fluorescência , Humanos , Injeções Intravenosas , Camundongos , Imagem Óptica , Especificidade de Órgãos , Biblioteca de Peptídeos , Peptídeos/administração & dosagem , Distribuição Tecidual
4.
Nat Biomed Eng ; 4(5): 560-571, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32393891

RESUMO

The oral administration of peptide drugs is hampered by their metabolic instability and limited intestinal uptake. Here, we describe a method for the generation of small target-specific peptides (less than 1,600 Da in size) that resist gastrointestinal proteases. By using phage display to screen large libraries of genetically encoded double-bridged peptides on protease-resistant fd bacteriophages, we generated a peptide inhibitor of the coagulation Factor XIa with nanomolar affinity that resisted gastrointestinal proteases in all regions of the gastrointestinal tract of mice after oral administration, enabling more than 30% of the peptide to remain intact, and small quantities of it to reach the blood circulation. We also developed a gastrointestinal-protease-resistant peptide antagonist for the interleukin-23 receptor, which has a role in the pathogenesis of Crohn's disease and ulcerative colitis. The de novo generation of targeted peptides that resist proteolytic degradation in the gastrointestinal tract should help the development of effective peptides for oral delivery.


Assuntos
Peptídeos/administração & dosagem , Peptídeos/uso terapêutico , Proteólise , Administração Oral , Sequência de Aminoácidos , Animais , Técnicas de Visualização da Superfície Celular , Cristalografia por Raios X , Feminino , Trato Gastrointestinal/metabolismo , Humanos , Isomerismo , Camundongos Endogâmicos BALB C , Modelos Moleculares , Peptídeo Hidrolases/metabolismo , Biblioteca de Peptídeos , Peptídeos/química , Estabilidade Proteica , Estrutura Secundária de Proteína , Receptores de Interleucina/antagonistas & inibidores , Receptores de Interleucina/metabolismo
5.
Nat Med ; 26(6): 878-885, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32451495

RESUMO

Programmed cell death 1 (PD-1) inhibitors have limited effect in pancreatic ductal adenocarcinoma (PDAC), underscoring the need to co-target alternative pathways. CXC chemokine receptor 4 (CXCR4) blockade promotes T cell tumor infiltration and is synergistic with anti-PD-1 therapy in PDAC mouse models. We conducted a phase IIa, open-label, two-cohort study to assess the safety, efficacy and immunobiological effects of the CXCR4 antagonist BL-8040 (motixafortide) with pembrolizumab and chemotherapy in metastatic PDAC (NCT02826486). The primary outcome was objective response rate (ORR). Secondary outcomes were overall survival (OS), disease control rate (DCR) and safety. In cohort 1, 37 patients with chemotherapy-resistant disease received BL-8040 and pembrolizumab. The DCR was 34.5% in the evaluable population (modified intention to treat, mITT; N = 29), including nine patients (31%) with stable disease and one patient (3.4%) with partial response. Median OS (mOS) was 3.3 months in the ITT population. Notably, in patients receiving study drugs as second-line therapy, the mOS was 7.5 months. BL-8040 increased CD8+ effector T cell tumor infiltration, decreased myeloid-derived suppressor cells (MDSCs) and further decreased circulating regulatory T cells. In cohort 2, 22 patients received BL-8040 and pembrolizumab with chemotherapy, with an ORR, DCR and median duration of response of 32%, 77% and 7.8 months, respectively. These data suggest that combined CXCR4 and PD-1 blockade may expand the benefit of chemotherapy in PDAC and warrants confirmation in subsequent randomized trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Retroperitoneais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos Imunológicos , Linfócitos T CD8-Positivos/patologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/secundário , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano/administração & dosagem , Leucovorina/administração & dosagem , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Linfonodos/patologia , Metástase Linfática , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Células Supressoras Mieloides/patologia , Neoplasias Pancreáticas/patologia , Peptídeos/administração & dosagem , Neoplasias Peritoneais/secundário , Receptores CXCR4/antagonistas & inibidores , Neoplasias Retroperitoneais/secundário , Taxa de Sobrevida , Linfócitos T Reguladores/patologia , Resultado do Tratamento
6.
Life Sci ; 251: 117625, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247003

RESUMO

OBJECTIVE: The present study was designed to investigate whether the novel peptide cysteine-based peptide (Cys-peptide) had protective effects on preeclamptic animal and cell models. METHODS: We investigated effects of Cys-peptide on (1) preeclamptic symptoms (e.g. hypertension, proteinuria, fetal growth restriction (FGR)) in preeclampia-like rat models induced by lipopolysaccharides (LPS), (2) TNFα-induced cytotoxicity of human umbilical vascular endothelial cells (HUVECs) and HTR-8 cells (an immortalised human trophoblast cell line), (3) endothelial dysfunction and injured angiogenesis, (4) migration and invasion of trophoblast cells induced by TNFα. RESULTS: Cys-peptide ameliorated LPS-induced hypertension, proteinuria and FGR and other PE symptoms in preeclampia-like rat models. In addition, Cys-peptide attenuated TNFα-induced cytotoxicity by decreasing soluble fms-like tyrosine kinase-1 (sFlt-1), endothelin-1 (ET-1) and tissue plasminogen activator (tPA) mRNA expression in both cells. Furthermore, Cys-peptide restored endothelial dysfunction and rescued angiogenesis caused by TNFα in vitro. Importantly, Cys-peptide could reverse insufficient ability to invade and migrate of trophoblast cells. CONCLUSIONS: These results suggest Cys-peptide can play beneficial roles in preeclampsia-like rat and cell models. Therefore, we propose that Cys-peptide is probably a novel therapeutic candidate for PE.


Assuntos
Cisteína/química , Retardo do Crescimento Fetal/prevenção & controle , Peptídeos/administração & dosagem , Pré-Eclâmpsia/prevenção & controle , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão/prevenção & controle , Peptídeos/química , Peptídeos/farmacologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Proteinúria/prevenção & controle , Ratos , Ratos Sprague-Dawley , Trofoblastos/metabolismo , Fator de Necrose Tumoral alfa/administração & dosagem
7.
PLoS One ; 15(3): e0229499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126102

RESUMO

Excitotoxicity mediated by the N-methyl-D-aspartate receptor (NMDAR) is believed to be a primary mechanism of neuronal injury following stroke. Thus, many drugs and therapeutic peptides were developed to inhibit either the NMDAR at the cell surface or its downstream intracellular death-signaling cascades. Nevertheless, the majority of focal ischemia studies concerning NMDAR antagonism were performed using the intraluminal suture-induced middle cerebral arterial occlusion (MCAO) model, which produces a large cortical and subcortical infarct leading to hypothalamic damage and fever in experimental animals. Here, we investigated whether NMDAR antagonism by drugs and therapeutic peptides was neuroprotective in a mouse model of distal MCAO (dMCAO), which produces a small cortical infarct sparing the hypothalamus and other subcortical structures. For establishment of this model, mice were subjected to dMCAO under normothermic conditions or body-temperature manipulations, and in the former case, their brains were collected at 3-72 h post-ischemia to follow the infarct development. These mice developed cortical infarction 6 h post-ischemia, which matured by 24-48 h post-ischemia. Consistent with the hypothesis that the delayed infarction in this model can be alleviated by neuroprotective interventions, hypothermia strongly protected the mouse brain against cerebral infarction in this model. To evaluate the therapeutic efficacy of NMDAR antagonism in this model, we treated the mice with MK801, Tat-NR2B9c, and L-JNKI-1 at doses that were neuroprotective in the MCAO model, and 30 min later, they were subjected to 120 min of dMCAO either in the awake state or under anesthesia with normothermic controls. Nevertheless, NMDAR antagonism, despite exerting pharmacological effects on mouse behavior, repeatedly failed to show neuroprotection against cerebral infarction in this model. The lack of efficacy of these treatments is reminiscent of the recurrent failure of NMDAR antagonism in clinical trials. While our data do not exclude the possibility that these treatments could be effective at a different dose or treatment regimen, they emphasize the need to test drug efficacy in different stroke models before optimal doses and treatment regimens can be selected for clinical trials.


Assuntos
Infarto Cerebral/prevenção & controle , Maleato de Dizocilpina/administração & dosagem , Hipotermia Induzida/métodos , Infarto da Artéria Cerebral Média/terapia , Animais , Infarto Cerebral/etiologia , Modelos Animais de Doenças , Maleato de Dizocilpina/farmacologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/etiologia , Masculino , Camundongos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Resultado do Tratamento
8.
J Agric Food Chem ; 68(8): 2381-2392, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32037817

RESUMO

Increasing level of inflammation and oxidative stress could lead to memory impairment. The purpose of this study was to determine the neuroprotective effects of walnut peptides against memory deficits induced by lipopolysaccharide (LPS) in mice and further to explore the underlying anti-inflammatory mechanisms against LPS-elicited inflammation in BV-2 cells. Results showed that walnut protein hydrolysate (WPH) and its low-molecular-weight fraction (WPHL) could ameliorate the memory deficits induced by LPS via normalizing the inflammatory response and oxidative stress in brain, especially WPHL. Furthermore, 18 peptides with anti-inflammatory activities on LPS-activated BV-2 cells were identified from WPHL and it was found that Trp, Gly, and Leu residues in peptides might contribute to the anti-inflammation. Meanwhile, the strong anti-inflammatory effects of LPF, GVYY, and APTLW might be related to their hydrophobic and aromatic amino acid residues as well. LPF, GVYY, and APTLW could reduce the content of proinflammatory mediators and cytokines by downregulating related enzyme expressions and mRNA expressions. Additionally, ROS and mitochondria homeostasis might also contribute to their anti-inflammatory effects.


Assuntos
Anti-Inflamatórios/administração & dosagem , Disfunção Cognitiva/tratamento farmacológico , Juglans/química , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/administração & dosagem , Animais , Anti-Inflamatórios/química , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/psicologia , Humanos , Lipopolissacarídeos/efeitos adversos , Aprendizagem em Labirinto , Camundongos , Peso Molecular , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/química , Nozes/química , Peptídeos/química
9.
APMIS ; 128(5): 387-389, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32105360

RESUMO

Tumor tissue often has an insufficient nutritional supply, in part due to compression of the vascular network from an increased interstitial fluid pressure. We have shown that the antisecretory factor peptide AF-16 can reduce this pressure in experimental rat breast tumors. In this work we studied if AF-16 administration opened up to an increased vascular volume in these tumors. Sprague-Dawley rats were given dimethylbenxanthracene and developed mammary tumors which were studied. Evans Blue was used as an intravascular volume indicator. Under anesthesia the rats were given AF-16 or solvent intranasally, and Evans Blue was injected i.v. 45 min later. Tumors and various organs were dissected and Evans Blue was extracted and colorimetrically quantified. Tumors had a significantly higher vascular volume after AF-16 administration as compared to other organs. Liver and renal vascular volumes were also increased but to a lesser degree than in the tumors. The results indicate that AF16 could be a candidate for increasing vascular access for chemotherapy in cancer therapy.


Assuntos
Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/patologia , Peptídeos/administração & dosagem , Grau de Desobstrução Vascular/efeitos dos fármacos , Animais , Feminino , Rim/patologia , Fígado/patologia , Neuropeptídeos , Ratos , Ratos Sprague-Dawley
10.
J Food Sci ; 85(3): 834-842, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32078745

RESUMO

Osteoporosis is a degenerative disease that threatens bone health of the elderly (especially postmenopausal women). Since osteoporosis is important to prevent, the aim of this study was to investigate the regulation of desalted duck egg white peptides (DPs) on osteoporosis. In this study, the effects of DPs on bone formation were evaluated using MC3T3-E1 cells and ovariectomized (OVX) rats. DPs significantly enhanced the preosteoblasts proliferation, differentiation, and matrix mineralization via the upregulation of wnt3a expression, low-density lipoprotein receptor-related protein-5 (LRP-5), ß-catenin, runt-related transcription factor 2 (Runx2), and osteoprotegerin (OPG) (P < 0.05). The intracellular calcium concentration was significantly elevated by DPs (P < 0.05), which is attributed to calcium influx and L-type calcium channels. Additionally, OVX rat model experiment indicated that DPs (600 mg/kg bw) had a superior effect against bone loss induced by estrogen deficiency, as it significantly declined bone turnover markers, and significantly increased biomechanical parameters (P < 0.05). Mineralized bone surfaces and bone microstructure were also obviously improved by DPs treatment. Immunohistochemical analysis showed that receptor activator of nuclear factor κ B (RANK) expression of tibia in DPs group was significantly reduced compared with the model group (P < 0.05). Our results demonstrated that DPs could enhance preosteoblasts differentiation and antiosteoporosis via wnt/ß-catenin signal pathway and several key osteogenic transcription factors such as Runx2 and OPG. PRACTICAL APPLICATION: High-value utilization of salted duck egg white, a byproduct of food industry, is worthy of in-depth study. Desalted duck egg white peptides (DPs) were proved to promote bone formation, which suggests the potentials of DPs as cofactors in osteoporosis prevention.


Assuntos
Clara de Ovo/química , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Peptídeos/administração & dosagem , Animais , Osso e Ossos/metabolismo , Cálcio/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Patos , Feminino , Humanos , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Osteoporose Pós-Menopausa/genética , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/fisiopatologia , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteína Wnt3/genética , Proteína Wnt3/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
11.
Int J Nanomedicine ; 15: 1117-1128, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110011

RESUMO

Introduction: Antibiotic-resistant bacteria kill 25,000 people every year in the EU. Patients subject to recurrent lung infections are the most vulnerable to severe or even lethal infections. For these patients, pulmonary delivery of antibiotics would be advantageous, since inhalation can achieve higher concentration in the lungs than iv administration and can provide a faster onset of action. This would allow for the delivery of higher doses and hence reduce the number of treatments required. We report here about a new nanosystem (M33-NS) obtained by capturing SET-M33 peptide on single-chain dextran nanoparticles. SET-M33 is a non-natural antimicrobial peptide synthesized in branched form. This form gives the peptide resistance to degradation in biological fluids. SET-M33 has previously shown efficacy in vitro against about one hundred of Gram-negative multidrug and extensively drug-resistant clinical isolates and was also active in preclinical infection models of pneumonia, sepsis and skin infections. Methods: The new nanosystem was evaluated for its efficacy in bacteria cells and in a mouse model of pneumonia. Toxicity and genotoxicity were also tested in vitro. Biodistribution and pharmacokinetic studies in healthy rats were carried out using a radiolabeled derivative of the nanosystem. Results: The M33-nanosystem, studied here, showed to be effective against Pseudomonas aeruginosa in time-kill kinetic experiments. Cytotoxicity towards different animal cell lines was acceptable. Lung residence time of the antimicrobial peptide, administered via aerosol in healthy rats, was markedly improved by capturing SET-M33 on dextran nanoparticles. M33-NS was also efficient in eradicating pulmonary infection in a BALB/c mouse model of pneumonia caused by P. aeruginosa. Discussion: This study revealed that the encapsulation of the antimicrobial peptide in dextran nanoparticles markedly improved lung residence time of the peptide administered via aerosol. The result has to be considered among the aims of the development of a new therapeutic option for patients suffering recurrent infections, that will benefit from high local doses of persistent antimicrobials.


Assuntos
Antibacterianos/administração & dosagem , Nanopartículas/administração & dosagem , Peptídeos/administração & dosagem , Infecções por Pseudomonas/tratamento farmacológico , Administração por Inalação , Animais , Antibacterianos/farmacologia , Dextranos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Nanopartículas/química , Peptídeos/síntese química , Peptídeos/farmacologia , Pneumonia Bacteriana/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos , Terapia Respiratória , Distribuição Tecidual
12.
BMC Vet Res ; 16(1): 60, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070332

RESUMO

BACKGROUND: Weaning is one of the most critical transition stages of the swine production cycle, as the piglet gut physiology and microbiome need to rapidly adapt to changes in diet and environmental conditions. Based on their potential for producing a vast array of bioactive molecules, peptide formulations represent a largely untapped source of compounds that could be developed into feed additives to benefit animal health and nutrition. In this context, a commercial-scale nursery trial was performed to evaluate the impact of low inclusion of a peptide-based feed additive (Peptiva, Vitech Bio-Chem Corporation) on the performance and fecal microbiome of weaned pigs. RESULTS: While no significant differences in body weight, daily gain, daily feed intake nor gain:feed were observed between control and treatment animals (P > 0.05), an effect of Peptiva on the fecal bacterial composition of weaned pigs was observed. The first main observation was that the fecal bacterial profiles from pigs fed Control-Phase II and Control Phase III diets were found to be very distinct, suggesting that a transition or succession stage had occurred between the two phases. Lactobacilli, represented by four main OTUs (Ssd-00002, Ssd-00019, Ssd-00025, and Ssd-00053), were more abundant at the end of Phase II (P < 0.05), while Streptococci, mostly represented by OTUs Ssd-00039 and Ssd-00048, were in higher abundance at the end of Phase III (P < 0.05). Secondly, the fecal bacterial composition from pigs fed Peptiva Phase II diets showed similarities to both Control-Phase II and Control Phase III samples, while there was no difference in fecal bacterial composition between Control-Phase III and Peptiva Phase III samples. For instance, OTUs Ssd-00019,and Ssd-00053 were in lower abundance in Peptiva Phase II samples compared to Control Phase II (P < 0.05), but no significant difference was observed in the abundance of these two OTUs when comparing Peptiva Phase II to Control Phase III (P > 0.05). CONCLUSIONS: Together, these results suggest that Peptiva can modulate the composition of the swine microbiome during a specific window of the nursery stage, potentially by accelerating its maturation.


Assuntos
Dieta/veterinária , Microbioma Gastrointestinal , Suínos/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias/crescimento & desenvolvimento , Peptídeos/administração & dosagem , Distribuição Aleatória , Suínos/crescimento & desenvolvimento , Suínos/microbiologia , Desmame , Ganho de Peso
13.
Am J Gastroenterol ; 115(4): 596-602, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32022721

RESUMO

INTRODUCTION: To inform the patient-centered discussion regarding comparative outcomes with irritable bowel syndrome/chronic idiopathic constipation pharmacotherapy, we evaluated reasons and timing of discontinuation of FDA-approved pharmacotherapy for irritable bowel syndrome and chronic idiopathic constipation in a large observational real-world cohort. METHODS: We identified patients initiating lubiprostone or linaclotide within the University of Michigan Electronic Medical Record (2012-2016). Medication start and stop dates were determined in manual chart review including detailed review of all documentation including office notes and telephone encounters. A Cox model was constructed to predict the hazard of discontinuation. RESULTS: On multivariate analysis of 1,612 patients, linaclotide users had a lower risk of discontinuing therapy than lubiprostone users for any reason (hazard ratio [HR] = 0.6, 95% confidence interval [CI] 0.5-0.8). At 3 and 12 months, the overall discontinuation rates were 23% and 43% for lubiprostone compared with 14% and 24% for linaclotide. Over the first year of therapy, more than half of discontinuations due to intolerance occurred in the first 3 months for both drugs. Linaclotide users were more likely to discontinue due to intolerance (HR = 1.6 [95% CI, 1.2-2.3]) but less likely to discontinue due to insufficient efficacy of therapy (HR = 0.5 [95% CI, 0.4-0.8]). IBS diagnosis increased the hazard of discontinuation of lubiprostone relative to linactolide (HR = 1.4, 95% CI, 1.1-1.6). Loss of prescription drug coverage remained a common reason for discontinuation over the first year of therapy. DISCUSSION: Individuals appear more likely to discontinue lubiprostone than linaclotide overall, but more likely to discontinue linaclotide compared with lubiprostone due to intolerance (mostly diarrhea). Most discontinuations due to intolerance occur in the first 3 months. These results may be useful in individualized treatment selection and enhancing patient knowledge regarding long-term outcomes.


Assuntos
Constipação Intestinal/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Síndrome do Intestino Irritável/tratamento farmacológico , Lubiprostona/administração & dosagem , Adesão à Medicação , Peptídeos/administração & dosagem , Doença Crônica , Feminino , Humanos , Masculino , Michigan , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Open Biol ; 10(2): 190235, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32019478

RESUMO

Cancer-specific mutations can lead to peptides of unique sequence presented on MHC class I to CD8 T cells. These neoantigens can be potent tumour-rejection antigens, appear to be the driving force behind responsiveness to anti-CTLA-4 and anti-PD1/L1-based therapies and have been used to develop personalized vaccines. The platform for delivering neoantigen-based vaccines has varied, and further optimization of both platform and adjuvant will be necessary to achieve scalable vaccine products that are therapeutically effective at a reasonable cost. Here, we developed a platform for testing potential CD8 T cell tumour vaccine candidates. We used a high-affinity alpaca-derived VHH against MHC class II to deliver peptides to professional antigen-presenting cells. We show in vitro and in vivo that peptides derived from the model antigen ovalbumin are better able to activate naive ovalbumin-specific CD8 T cells when conjugated to an MHC class II-specific VHH when compared with an irrelevant control VHH. We then used the VHH-peptide platform to evaluate a panel of candidate neoantigens in vivo in a mouse model of pancreatic cancer. None of the candidate neoantigens tested led to protection from tumour challenge; however, we were able to show vaccine-induced CD8 T cell responses to a melanoma self-antigen that was augmented by combination therapy with the synthetic cytokine mimetic Neo2/15.


Assuntos
Antígenos de Histocompatibilidade Classe II/imunologia , Interleucina-2/administração & dosagem , Melanoma/tratamento farmacológico , Peptídeos/administração & dosagem , Anticorpos de Domínio Único/metabolismo , Animais , Antígenos de Neoplasias/imunologia , Autoantígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Camelídeos Americanos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Interleucina-2/imunologia , Melanoma/imunologia , Camundongos , Peptídeos/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Vacinas de Subunidades , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Biochem Biophys Res Commun ; 524(4): 903-909, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32057366

RESUMO

PURPOSE: The aim of this study was to investigate the cardiac repair effect of human bone marrow mesenchymal stromal cells-derived extracellular vesicles (MSC-EVs) after intramyocardial injection in free form or encapsulated within a self-assembling peptide hydrogel modified with SDKP motif, in a rat model of myocardial infarction (MI). METHODS: MSC-EVs were isolated by ultracentrifuge and characterized for physical parameters and surface proteins. Furthermore, cellular uptake and cardioprotective effects of MSC-EVs were evaluated in vitro using neonatal mouse cardiomyocytes (NMCMs). In vivo effects of MSC-EVs on cardiac repair were studied in rat MI model by comparing the vehicle group (injected with PBS), EV group (injected with MSC-EVs) and Gel + EV group (injected with MSC-EVs encapsulated in (RADA)4-SDKP hydrogel) with respect to cardiac function and fibrotic area using echocardiography and Masson's trichrome staining, respectively. Histological sections were assessed by α-SMA and CD68 immunostaining to investigate the angiogenic and anti-inflammatory effects of the MSC-EVs. RESULTS: We observed the uptake of MSC-EVs into NMCMs which led to NMCMs protection against H2O2-induced oxidative stress by substantial reduction of apoptosis. In myocardial infarcted rats, cardiac function was improved after myocardial injection of MSC-EVs alone or in conjunction with (RADA)4-SDKP hydrogel. This functional restoration coincided with promotion of angiogenesis and decrement of fibrosis and inflammation. CONCLUSION: These data demonstrated that MSC-EVs can be used alone as a potent therapeutic agent for improvement of myocardial infarction.


Assuntos
Vesículas Extracelulares/transplante , Células-Tronco Mesenquimais/química , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Peptídeos/administração & dosagem , Actinas/genética , Actinas/metabolismo , Animais , Animais Recém-Nascidos , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Transporte Biológico , Biomarcadores/metabolismo , Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Expressão Gênica , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/química , Peróxido de Hidrogênio/farmacologia , Injeções Intramusculares , Células-Tronco Mesenquimais/citologia , Camundongos , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo , Cultura Primária de Células , Ratos
16.
J Agric Food Chem ; 68(6): 1621-1633, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967468

RESUMO

Collagen peptides can promote wound healing and are closely related to microbiome colonization. We investigated the relationship among collagen peptides, wound healing, and wound microflora colonization by administering the murine wound model with Salmo salar skin collagen peptides (Ss-SCPs) and Tilapia nilotica skin collagen peptides (Tn-SCPs). We analyzed the vascular endothelial growth factor (VEGF), fibroblast growth factors (ß-FGF), pattern recognition receptor (NOD2), antimicrobial peptides (ß-defence14, BD14), proinflammatory (TNF-α, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines, macrophages, neutrophil infiltration levels, and microbial communities in the rat wound. The healing rates of the Ss-SCP- and Tn-SCP-treated groups were significantly accelerated, associated with decreased TNF-α, IL-6, and IL-8 and upregulated BD14, NOD2, IL-10, VEGF, and ß-FGF. Accelerated healing in the collagen peptide group shows that the wound microflora such as Leuconostoc, Enterococcus, and Bacillus have a positive effect on wound healing (P < 0.01). Other microbiome species such as Stenotrophomonas, Bradyrhizobium, Sphingomonas, and Phyllobacterium had a negative influence and decreased colonization (P < 0.01). Altogether, these studies show that collagen peptide could upregulate wound NOD2 and BD14, which were implicated in microflora colonization regulation in the wound tissue and promoted wound healing by controlling the inflammatory reaction and increasing wound angiogenesis and collagen deposition.


Assuntos
Colágeno/química , Proteínas de Peixes/química , Microbiota/efeitos dos fármacos , Proteína Adaptadora de Sinalização NOD2/genética , Peptídeos/administração & dosagem , Pele/química , Ferimentos e Lesões/fisiopatologia , beta-Defensinas/genética , Administração Cutânea , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ciclídeos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Masculino , Camundongos , Proteína Adaptadora de Sinalização NOD2/imunologia , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Salmo salar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/microbiologia , beta-Defensinas/imunologia
17.
Br J Radiol ; 93(1108): 20190817, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31899657

RESUMO

OBJECTIVE: To determine if MRI findings prior to intra-articular corticosteroid hip infiltration are related to treatment outcomes. METHODS: This prospective outcome study with retrospective MRI evaluation includes 100 consecutive patients with MRI within 6 months before a therapeutic intra-articular hip injection. Labrum, bone marrow, acetabular and femoral cartilage abnormalities were assessed by two radiologists blinded to patient outcomes: the proportion reporting "improvement" on the Patient's Global Impression of Change (PGIC) scale at 1 day, 1 week and 1 month follow-up were compared based on MRI findings using χ2. The t-test was used to compare pain change scores with MRI abnormalities. RESULTS: Patients with a normal labrum in the posterosuperior quadrant were more likely to report PGIC "improvement" at 1 week compared to labral degeneration (p = 0.048). Significant differences in pain change scores were found at all time points for the labral anteroinferior quadrant (p = 0.001, 1 day; p = 0.010, 1 week; p = 0.034, 1 month) with the highest reduction in patients with labral degeneration. Females were 2.80 times more likely to report clinically relevant "improvement" at 1 day (p = .049) and 2.90 times more likely to report clinically relevant "improvement" at 1 month (p = .045). CONCLUSION: Cartilage defects and marrow abnormalities were not associated with outcomes. Patients with a normal labrum in the posterosuperior quadrant had better outcomes at 1 week. Patients with labral degeneration of the anteroinferior quadrant had higher levels of pain reduction at all time points. Females were significantly more likely to report PGIC "improvement". ADVANCES IN KNOWLEDGE: A significant treatment outcome was observed amongst gender, although there were no significant differences in the MRI findings.


Assuntos
Articulação do Quadril/diagnóstico por imagem , Imagem por Ressonância Magnética Intervencionista , Osteoartrite do Quadril/diagnóstico por imagem , Peptídeos/administração & dosagem , Acetábulo/diagnóstico por imagem , Adulto , Idoso , Medula Óssea/diagnóstico por imagem , Cartilagem/diagnóstico por imagem , Distribuição de Qui-Quadrado , Feminino , Articulação do Quadril/efeitos dos fármacos , Humanos , Injeções Intra-Articulares/métodos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/tratamento farmacológico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
18.
J Pept Sci ; 26(3): e3241, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31984553

RESUMO

The dual interaction with integrins and neuropilin-1 receptor is the peculiar feature of iRGD peptide. Hence, in the present study, two iRGD peptide analogs were synthesized with DOTAGA and NODAGA as bifunctional chelator and aminohexanoic acid as a spacer for radiometalation with 68 GaCl3 . Negatively charged 68 Ga-DOTAGA-iRGD and neutral 68 Ga-NODAGA-iRGD radiotracers were investigated through in vitro cell uptake studies and in vivo biodistribution studies. Significant internalization of radiotracers in murine melanoma B16F10 cells was observed during in vitro studies. During in vivo studies, tumor uptake was higher for neutral 68 Ga-NODAGA-iRGD, but 68 Ga-DOTAGA-iRGD exhibited better tumor-to-blood ratio due to faster blood clearance. High kidney uptake of the two radiotracers was the limitation, which needs to be resolved through modification either in the peptide backbone or spacer/chelator.


Assuntos
Quelantes/química , Radioisótopos de Gálio/química , Melanoma Experimental/metabolismo , Peptídeos/farmacocinética , Acetatos/química , Administração Intravenosa , Anidridos/química , Animais , Linhagem Celular Tumoral , Compostos Heterocíclicos com 1 Anel/química , Integrinas/química , Camundongos , Neuropilina-1/química , Peptídeos/administração & dosagem , Peptídeos/química
19.
J Agric Food Chem ; 68(8): 2393-2405, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31995979

RESUMO

Hyperglycemia-induced oxidative stress can cause liver damage in diabetes, and protein hydrolysates with antidiabetic and antioxidant properties are emerging as a potential therapy. In this study, protective effects of casein hydrolysates against live oxidative damage in streptozotocin/high-fat-induced diabetic rats were studied and potentially bioactive peptides were explored by an integrated approach of differential peptide and in silico analysis. Results showed that different casein hydrolysates significantly alleviated liver oxidative damage (p < 0.05) via different mechanisms. Particularly, casein hydrolyzed by a papain-flavourzyme combination (P-FCH) treatment significantly improved liver antioxidant enzyme activities by enhancing nuclear factor erythroid 2-related factor 2 (Nrf2) transcription (p < 0.05). Furthermore, 18 peptides were screened as potential bioactive peptides by analyzing differential peptides among different hydrolysates combined with in silico prediction. Among them, the dipeptide WM might directly inhibit the Kelch-like ECH-associated protein 1 (Keap1)-Nrf2 interaction as potential Nrf2 activators. These results suggested that P-FCH might be an alternative way to treat liver damage in diabetes.


Assuntos
Caseínas/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hepatopatias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/administração & dosagem , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Hepatopatias/genética , Hepatopatias/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
20.
ACS Appl Mater Interfaces ; 12(3): 3453-3464, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31895537

RESUMO

The common phenomenon that the nonviral vectors have much lower transfection efficiency in vivo than in vitro greatly restricts their further developments and applications. Possible reasons are lacking targeting ability, elimination by the reticuloendothelial system (RES), and insufficient nuclear transport. Here, a novel, flexible, and deformable polymer Fe@PEI-R12 (tLyp-1-NLS) is reported for shortening the gap between in vitro and in vivo gene transfection efficiency. The amorphous network structure Fe@PEI with deformation ability acquired by coordination cross-linking of Fe3+ and low-molecular-weight polyethylenimine (LMW-PEI) constructs the core and serves as the gene reservoir, and it can squeeze out through RES filter holes when trapped in the spleen. The bifunctional peptide R12 provided tumor targeting and enhanced nuclear delivery ability. Additionally, the Fe3+ from Fe@PEI-R12 could trigger endogenous hydrogen peroxide (H2O2) decomposition to produce O2, thereby reducing the adverse effects of tumor hypoxia. It is demonstrated that the Fe@PEI-R12/pDNA complexes could pass through membrane filters, subsequently achieving long circulation time, and Fe@PEI-R12 had a tendency to accumulate in tumor tissue and mediate pGL3-control expression. Therefore, the multifunctional nanoplatform has the potential for effective in vivo gene delivery.


Assuntos
Compostos Férricos/química , Terapia Genética/instrumentação , Nanoestruturas/química , Neoplasias/terapia , Peptídeos/administração & dosagem , Peptídeos/química , Transfecção/métodos , Animais , Terapia Genética/métodos , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/genética , Peptídeos/genética , Polietilenoimina/química , Transfecção/instrumentação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA