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1.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446151

RESUMO

The estrogen metabolite 2-methoxyestradiol (2ME) is a promissory anticancer drug mainly because of its pro-apoptotic properties in cancer cells. However, the therapeutic use of 2ME has been hampered due to its low solubility and bioavailability. Thus, it is necessary to find new ways of administration for 2ME. Zeolites are inorganic aluminosilicates with a porous structure and are considered good adsorbents and sieves in the pharmaceutical field. Here, mordenite-type zeolite nanoparticles were loaded with 2ME to assess its efficiency as a delivery system for prostate cancer treatment. The 2ME-loaded zeolite nanoparticles showed an irregular morphology with a mean hydrodynamic diameter of 250.9 ± 11.4 nm, polydispersity index of 0.36 ± 0.04, and a net negative surface charge of -34 ± 1.73 meV. Spectroscopy with UV-vis and Attenuated Total Reflectance Infrared Fourier-Transform was used to elucidate the interaction between the 2ME molecules and the zeolite framework showing the formation of a 2ME-zeolite conjugate in the nanocomposite. The studies of adsorption and liberation determined that zeolite nanoparticles incorporated 40% of 2ME while the liberation of 2ME reached 90% at pH 7.4 after 7 days. The 2ME-loaded zeolite nanoparticles also decreased the viability and increased the mRNA of the 2ME-target gene F-spondin, encoded by SPON1, in the human prostate cancer cell line LNCaP. Finally, the 2ME-loaded nanoparticles also decreased the viability of primary cultures from mouse prostate cancer. These results show the development of 2ME-loaded zeolite nanoparticles with physicochemical and biological properties compatible with anticancer activity on the human prostate and highlight that zeolite nanoparticles can be a good carrier system for 2ME.


Assuntos
Nanopartículas , Neoplasias da Próstata , Zeolitas , Masculino , Humanos , Animais , Camundongos , Zeolitas/química , Próstata , Neoplasias da Próstata/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanopartículas/química
2.
Onco Targets Ther ; 15: 783-797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35899081

RESUMO

Potassium (K+) channels are highly regulated membrane proteins that control the potassium ion flux and respond to different cellular stimuli. These ion channels are grouped into three major families, Kv (voltage-gated K+ channel), Kir (inwardly rectifying K+ channel) and K2P (two-pore K+ channels), according to the structure, to mediate the K+ currents. In cancer, alterations in K+ channel function can promote the acquisition of the so-called hallmarks of cancer - cell proliferation, resistance to apoptosis, metabolic changes, angiogenesis, and migratory capabilities - emerging as targets for the development of new therapeutic drugs. In this review, we focus our attention on the different K+ channels associated with the most relevant and prevalent cancer types. We summarize our knowledge about the potassium channels structure and function, their cancer dysregulated expression and discuss the K+ channels modulator and the strategies for designing new drugs.

3.
Curr Mol Med ; 22(10): 908-918, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34875988

RESUMO

BACKGROUND: Sarcopenia is a progressive and generalized skeletal muscle disorder characterized by muscle weakness, loss of muscle mass, and decline in the capacity of force generation. Aging can cause sarcopenia. Several therapeutic strategies have been evaluated to prevent or alleviate this disorder. One of them is angiotensin 1-7 [Ang-(1-7)], an anti-atrophic peptide for skeletal muscles that regulates decreased muscle mass for several causes, including aging. Another regulator of muscle mass and function is andrographolide, a bicyclic diterpenoid lactone that decreases the nuclear factor kappa B (NF-κB) signaling and attenuates the severity of some muscle diseases. OBJECTIVE: Evaluate the effect of combined administration of Ang-(1-7) with andrographolide on the physical performance, muscle strength, and fiber´s diameter in a murine model of sarcopenia by aging. METHODS: Aged male mice of the C57BL/6J strain were treated with Andrographolide, Ang-(1-7), or combined for three months. The physical performance, muscle strength, and fiber´s diameter were measured. RESULTS: The results showed that aged mice (24 months old) treated with Ang-(1-7) or Andrographolide improved their performance on a treadmill test, muscle strength, and their fiber´s diameter compared to aged mice without treatment. The combined administration of Ang-(1-7) with andrographolide to aged mice has an enhanced synergically effect on physical performance, muscle strength, and fiber´s diameter. CONCLUSION: Our results indicated that in aged mice, the effects of andrographolide and Ang-(1-7) on muscle function, strength, and fiber´s diameter are potentiated.


Assuntos
Diterpenos , Doenças Musculares , Sarcopenia , Angiotensina I/farmacologia , Angiotensina I/uso terapêutico , Animais , Diterpenos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético , Doenças Musculares/tratamento farmacológico , Doenças Musculares/patologia , Fragmentos de Peptídeos , Sarcopenia/tratamento farmacológico , Sarcopenia/patologia
4.
Pharmaceutics ; 15(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36678639

RESUMO

Skin has a preventive role against any damage raised by harmful microorganisms and physical and chemical assaults from the external environment that could affect the body's internal organs. Dermis represents the main section of the skin, and its contribution to skin physiology is critical due to its diverse cellularity, vasculature, and release of molecular mediators involved in the extracellular matrix maintenance and modulation of the immune response. Skin structure and complexity limit the transport of substances, promoting the study of different types of nanoparticles that penetrate the skin layers under different mechanisms intended for skin illness treatments and dermo-cosmetic applications. In this work, we present a detailed morphological description of the dermis in terms of its structures and resident cells. Furthermore, we analyze the role of the dermis in regulating skin homeostasis and its alterations in pathophysiological conditions, highlighting its potential as a therapeutic target. Additionally, we describe the use of nanoparticles for skin illness treatments focused on dermis release and promote the use of metal-organic frameworks (MOFs) as an integrative strategy for skin treatments.

5.
Nanomedicine (Lond) ; 16(28): 2521-2538, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34743611

RESUMO

Skeletal muscle is integral to the functioning of the human body. Several pathological conditions, such as trauma (primary lesion) or genetic diseases such as Duchenne muscular dystrophy (DMD), can affect and impair its functions or exceed its regeneration capacity. Tissue engineering (TE) based on natural, synthetic and hybrid biomaterials provides a robust platform for developing scaffolds that promote skeletal muscle regeneration, strength recovery, vascularization and innervation. Recent 3D-cell printing technology and the use of nanocarriers for the release of drugs, peptides and antisense oligonucleotides support unique therapeutic alternatives. Here, the authors present recent advances in scaffold biomaterials and nano-based therapeutic strategies for skeletal muscle regeneration and perspectives for future endeavors.


Assuntos
Materiais Biocompatíveis , Alicerces Teciduais , Humanos , Músculo Esquelético/lesões , Músculo Esquelético/patologia , Regeneração , Engenharia Tecidual , Cicatrização
6.
Oxid Med Cell Longev ; 2021: 4493817, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34676021

RESUMO

Sarcopenic obesity (SO) is a combination of obesity and sarcopenia that primarily develops in older people. Patients with SO have high fat mass, low muscle mass, low muscle strength, and low physical function. SO relates to metabolic syndrome and an increased risk of morbimortality. The prevalence of SO varies because of lacking consensus criteria regarding its definition and the methodological difficulty in diagnosing sarcopenia and obesity. SO includes systemic alterations such as insulin resistance, increased proinflammatory cytokines, age-associated hormonal changes, and decreased physical activity at pathophysiological levels. Interestingly, these alterations are influenced by oxidative stress, which is a critical factor in altering muscle function and the generation of metabolic dysfunctions. Thus, oxidative stress in SO alters muscle mass, the signaling pathways that control it, satellite cell functions, and mitochondrial and endoplasmic reticulum activities. Considering this background, our objectives in this review are to describe SO as a highly prevalent condition and look at the role of oxidative stress in SO pathophysiology.


Assuntos
Obesidade/genética , Estresse Oxidativo/fisiologia , Sarcopenia/genética , Humanos , Pessoa de Meia-Idade
7.
Drug Deliv ; 28(1): 1020-1030, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34060399

RESUMO

NOD1 is an intracellular receptor that, when activated, induces gene expression of pro-inflammatory factors promoting macrophages and neutrophils recruitment at the infection site. However, iE-DAP, the dipeptide agonist that promotes this receptor's activation, cannot permeate cell membranes. To develop a nanocarrier capable of achieving a high and prolonged activation over time, iE-DAP was encapsulated in nanoparticles (NPs) made of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The physicochemical properties, colloidal stability, encapsulation efficiency, and cellular uptake of iE-DAP-loaded PHVB NPs were analyzed. Results evidenced that physicochemical properties of iE-DAP-loaded NPs remained stable over time, and NPs were efficiently internalized into cells, a process that depends on time and concentration. Moreover, our results showed that NPs elicited a controlled cargo release in vitro, and the encapsulated agonist response was higher than its free form, suggesting the possibility of activating intracellular receptors triggering an immune response through the release of NOD1 agonist.


Assuntos
Ácido Diaminopimélico/análogos & derivados , Nanopartículas/química , Proteína Adaptadora de Sinalização NOD1/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Ácido Diaminopimélico/administração & dosagem , Ácido Diaminopimélico/farmacologia , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Camundongos , Poliésteres/química , Células RAW 264.7
8.
Nat Commun ; 11(1): 1073, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103010

RESUMO

Denervation of skeletal muscles induces severe muscle atrophy, which is preceded by cellular alterations such as increased plasma membrane permeability, reduced resting membrane potential and accelerated protein catabolism. The factors that induce these changes remain unknown. Conversely, functional recovery following denervation depends on successful reinnervation. Here, we show that activation of nicotinic acetylcholine receptors (nAChRs) by quantal release of acetylcholine (ACh) from motoneurons is sufficient to prevent changes induced by denervation. Using in vitro assays, ACh and non-hydrolysable ACh analogs repressed the expression of connexin43 and connexin45 hemichannels, which promote muscle atrophy. In co-culture studies, connexin43/45 hemichannel knockout or knockdown increased innervation of muscle fibers by dorsal root ganglion neurons. Our results show that ACh released by motoneurons exerts a hitherto unknown function independent of myofiber contraction. nAChRs and connexin hemichannels are potential molecular targets for therapeutic intervention in a variety of pathological conditions with reduced synaptic neuromuscular transmission.


Assuntos
Acetilcolina/metabolismo , Gânglios Espinais/crescimento & desenvolvimento , Músculo Esquelético/inervação , Atrofia Muscular/patologia , Receptores Nicotínicos/metabolismo , Acetilcolina/análogos & derivados , Acetilcolina/farmacologia , Animais , Permeabilidade da Membrana Celular/fisiologia , Células Cultivadas , Conexina 43/metabolismo , Conexinas/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Esquelético/metabolismo
9.
J Control Release ; 313: 14-23, 2019 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-31622693

RESUMO

Neutrophils are crucial modulators of the inflammation process, and their uncontrolled response worsens several chronic pathologies. The p38 mitogen-activated protein kinases (MAPKs) activity is critical for normal immune and inflammatory response through the regulation of pro-inflammatory cytokines synthesis. In this work, we study the effect of hybrid lipid-polymer nanoparticles loaded with the p38 MAPK inhibitor SB203580 in an acute and chronic inflammatory model in zebrafish containing a transgenic neutrophil cell line that constitutively expresses a green fluorescent protein. We identify the existence of at least two neutrophils subpopulation involved in the response during the acute inflammation triggered; a first-responder p38α-independent subset and a second-responder p38α-dependent subset. In the case of chronic inflammation, neutrophils recruited in the intestine only during the inflammation process, migrate in a p38α-dependent manner. Likewise, we establish that SB203580-loaded in NPs exerts their action during at least a double period than the inhibitor administers directly in both types of inflammation. Our results demonstrate the exceptional potential of the zebrafish as an inflammatory model for studying novel nanotherapeutics that selectively inhibit the neutrophils response, and to identify functional neutrophils subpopulations involved in the inflammation process.


Assuntos
Anti-Inflamatórios não Esteroides/química , Materiais Biocompatíveis/química , Imidazóis/química , Inflamação/tratamento farmacológico , Nanocápsulas/química , Neutrófilos/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Piridinas/química , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular , Composição de Medicamentos , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imidazóis/farmacologia , Larva/efeitos dos fármacos , Modelos Animais , Neutrófilos/citologia , Imagem Óptica , Fosfatidiletanolaminas/química , Poliésteres/química , Polietilenoglicóis/química , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Transdução de Sinais , Nanomedicina Teranóstica , Peixe-Zebra
10.
Curr Mol Med ; 20(1): 60-71, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31530262

RESUMO

BACKGROUND: Sarcopenia is characterized by the loss of muscle mass and strength (muscle atrophy) because of aging or chronic diseases, such as chronic liver disease (CLD). Different mechanisms are involved in skeletal muscle atrophy, including decreased muscle fibre diameter and myosin heavy chain levels and increased ubiquitin-proteasome pathway activity, oxidative stress and myonuclear apoptosis. We recently found that all these mechanisms, except myonuclear apoptosis, which was not evaluated in the previous study, were involved in muscle atrophy associated with hepatotoxin 5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced CLD. OBJECTIVE: In the present study, we evaluated the involvement of myonuclear apoptosis in CLD-associated sarcopenia and the effect of N-acetyl cysteine (NAC) treatment on muscle strength and apoptosis, using a DDC-supplemented diet-fed mouse model. METHODS: Four-month-old male C57BL6 mice were fed with a standard or DDCsupplemented diet for six weeks in the absence or presence of NAC treatment. RESULTS: Our results showed that NAC attenuated the decrease in muscle fibre diameter and muscle strength associated with CLD-induced muscle wasting in gastrocnemius (GA) muscle of DDC-supplemented diet-fed mice. In addition, in GA muscle of the mice fed with DDC-supplemented diet-induced CLD showed increased myonuclear apoptosis compared with the GA muscle of the control diet-fed mice, as evidenced by increased apoptotic nuclei number, caspase-8 and caspase-9 expression, enzymatic activity of caspase-3 and BAX/BCL-2 ratio. NAC treatment inhibited all the mechanisms associated with myonuclear apoptosis in the GA muscle. CONCLUSION: To our knowledge, this is the first study which reports the redox regulation of muscle strength and myonuclear apoptosis in CLD-induced sarcopenia.


Assuntos
Acetilcisteína/farmacologia , Doença Hepática Terminal/tratamento farmacológico , Atrofia Muscular/tratamento farmacológico , Sarcopenia/tratamento farmacológico , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Doença Hepática Terminal/induzido quimicamente , Doença Hepática Terminal/complicações , Doença Hepática Terminal/patologia , Humanos , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Estresse Oxidativo/efeitos dos fármacos , Piridinas/toxicidade , Sarcopenia/etiologia , Sarcopenia/metabolismo , Sarcopenia/patologia
11.
Curr Protein Pept Sci ; 20(6): 536-546, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30947668

RESUMO

Several molecular mechanisms are involved in the regulation of skeletal muscle function. Among them, mitochondrial activity can be identified. The mitochondria is an important and essential organelle in the skeletal muscle that is involved in metabolic regulation and ATP production, which are two key elements of muscle contractibility and plasticity. Thus, in this review, we present the critical and recent antecedents regarding the mechanisms through which mitochondrial dysfunction can be involved in the generation and development of skeletal muscle pathologies, its contribution to detrimental functioning in skeletal muscle and its crosstalk with other typical signaling pathways related to muscle diseases. In addition, an update on the development of new strategies with therapeutic potential to inhibit the deleterious impact of mitochondrial dysfunction in skeletal muscle is discussed.


Assuntos
Mitocôndrias/fisiologia , Músculo Esquelético/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Autofagia , Humanos , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Espécies Reativas de Oxigênio/metabolismo , Sarcopenia/metabolismo , Sarcopenia/patologia , Transdução de Sinais
13.
Beilstein J Nanotechnol ; 9: 1328-1338, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977668

RESUMO

Nanotherapeutics is a promising field for numerous diseases and represents the forefront of modern medicine. In the present work, full atomistic computer simulations were applied to study poly(lactic acid) (PLA) nanoparticles conjugated with polyethylene glycol (PEG). The formation of this complex system was simulated using the reactive polarizable force field (ReaxFF). A full picture of the morphology, charge and functional group distribution is given. We found that all terminal groups (carboxylic acid, methoxy and amino) are randomly distributed at the surface of the nanoparticles. The surface design of NPs requires that the charged groups must surround the surface region for an optimal functionalization/charge distribution, which is a key factor in determining physicochemical interactions with different biological molecules inside the organism. Another important point that was investigated was the encapsulation of drugs in these nanocarriers and the prediction of the polymer-drug interactions, which provided a better insight into structural features that could affect the effectiveness of drug loading. We employed blind docking to predict NP-drug affinity testing on an antiaggregant compound, cilostazol. The results suggest that the combination of molecular dynamics ReaxFF simulations and blind docking techniques can be used as an explorative tool prior to experiments, which is useful for rational design of new drug delivery systems.

14.
Oxid Med Cell Longev ; 2018: 2063179, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29785242

RESUMO

Skeletal muscle atrophy is a pathological condition mainly characterized by a loss of muscular mass and the contractile capacity of the skeletal muscle as a consequence of muscular weakness and decreased force generation. Cachexia is defined as a pathological condition secondary to illness characterized by the progressive loss of muscle mass with or without loss of fat mass and with concomitant diminution of muscle strength. The molecular mechanisms involved in cachexia include oxidative stress, protein synthesis/degradation imbalance, autophagy deregulation, increased myonuclear apoptosis, and mitochondrial dysfunction. Oxidative stress is one of the most common mechanisms of cachexia caused by different factors. It results in increased ROS levels, increased oxidation-dependent protein modification, and decreased antioxidant system functions. In this review, we will describe the importance of oxidative stress in skeletal muscles, its sources, and how it can regulate protein synthesis/degradation imbalance, autophagy deregulation, increased myonuclear apoptosis, and mitochondrial dysfunction involved in cachexia.


Assuntos
Caquexia/genética , Caquexia/metabolismo , Atrofia Muscular/etiologia , Animais , Apoptose , Caquexia/patologia , Humanos , Atrofia Muscular/patologia , Estresse Oxidativo
15.
Nanoscale ; 10(28): 13375-13383, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29786742

RESUMO

The calcium (Ca2+) ion concentration in the blood serum is tightly regulated, and any abnormalities in the level of serum calcium ions are associated with many potentially dangerous diseases. Thus, monitoring of the Ca2+ ion concentration in the blood serum is of fundamental importance. Gold nanoparticle (GNP)-based colorimetric biosensors have enormous potential in clinical diagnostic applications due to their simplicity, versatility, and unique optical properties. In this study, we have developed an alendronate functionalized gold nanoparticle (GNP-ALD) system for the measurement of Ca2+ ion concentration in biological samples. The GNP-ALD system showed higher sensitivity towards the Ca2+ ion compared to adenosine diphosphate (ADP) or adenosine triphosphate (ATP). The strong interaction between the Ca2+ ion and ALD at the GNP/solution interface resulted in significant aggregation of the ALD conjugated GNPs, and induced a color change of the solution from red to blue, which could be visually observed with the naked eye. The interaction between the Ca2+ ion and GNP-ALD was characterized by UV-visible spectroscopy, transmission electron microscopy (TEM) imaging, and dynamic light scattering (DLS) analysis. Under the optimized conditions, the lower limit of Ca2+ ion detection using this method was found to be 25 µM and a linear response range from 25 µM to 300 µM Ca2+ ions was obtained with excellent discrimination against other metal ions. The GNP-ALD nanoprobe could successfully determine the ionized Ca2+ concentration in various serum samples and the results were validated using a commercial calcium assay kit. Moreover, as a practical application, we demonstrated the utility of this nanoprobe for the detection of cancer-associated hypercalcemia in a mouse model.


Assuntos
Alendronato/química , Cálcio/análise , Colorimetria , Hipercalcemia/diagnóstico , Nanopartículas Metálicas , Neoplasias/complicações , Animais , Feminino , Ouro , Hipercalcemia/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ratos Sprague-Dawley
16.
Vascul Pharmacol ; 101: 1-8, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29174014

RESUMO

Despite the numerous advantages offered by diverse platforms based on nanomedicine, several nanomaterials have shown significant cell toxicity that could induce chronic adverse effects on human health. Blood compatibility is one of the leading factors to consider for the design and development of nanosystems as therapeutics. Aforementioned is because systemic circulation is the gateway for most nano-drug therapeutic systems and its interactions with the blood components such as platelets could influence the maintenance of hemostasis and thrombus formation. Unfortunately, the thrombotoxicity of some nanomaterials regarding the activation/inhibition of platelets limits their biomedical applications. Additionally, the critical factors that drive those effects on platelet function are still not entirely elucidated. In this work, we describe the effect of different nanomaterials on the platelet function, its action mechanisms, and future potential as nanotherapeutics.


Assuntos
Plaquetas/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Nanomedicina , Nanopartículas/uso terapêutico , Animais , Plaquetas/metabolismo , Humanos , Nanopartículas/efeitos adversos , Segurança do Paciente , Medição de Risco
17.
Biol Chem ; 399(3): 253-264, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29140787

RESUMO

The transforming growth factor type-beta (TGF-ß) induces skeletal muscle atrophy characterised by a decrease in the fibre's diameter and levels of myosin heavy chain (MHC), also as an increase of MuRF-1 expression. In addition, TGF-ß induces muscle atrophy by a mechanism dependent on reactive oxygen species (ROS). TGF-ß signals by activating both canonical Smad-dependent, and non-canonical signalling pathways such as ERK1/2, JNK1/2, and p38 MAPKs. However, the participation of canonical and non-canonical signalling pathways in the TGF-ß atrophic effect on skeletal muscle is unknown. We evaluate the impact of Smad and MAPK signalling pathways on the TGF-ß-induced atrophic effect in C2C12 myotubes. The results indicate that TGF-ß activates Smad2/3, ERK1/2 and JNK1/2, but not p38 in myotubes. The pharmacological inhibition of Smad3, ERK1/2 and JNK1/2 activation completely abolished the atrophic effect of TGF-ß. Finally, the inhibition of these canonical and non-canonical pathways did not decrease the ROS increment, while the inhibition of ROS production entirely abolished the phosphorylation of Smad3, ERK1/2 and JNK1/2. These results suggest that TGF-ß requires Smad3, ERK1/2 and JNK1/2 activation to produce skeletal muscle atrophy. Moreover, the induction of ROS by TGF-ß is an upstream event to canonical and non-canonical pathways.


Assuntos
Atrofia Muscular/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Fosforilação , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo
18.
Sci Rep ; 7(1): 14351, 2017 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084990

RESUMO

Growth factors have great therapeutic potential for various disease therapy and tissue engineering applications. However, their clinical efficacy is hampered by low bioavailability, rapid degradation in vivo and non-specific biodistribution. Nanoparticle based delivery systems are being evaluated to overcome these limitations. Herein, we have developed a thermosensitive heparin nanosponge (Hep-NS) by a one step photopolymerization reaction between diacrylated pluronic and thiolated heparin molecules. The amount of heparin in Hep-NS was precisely controlled by varying the heparin amount in the reaction feed. Hep-NS with varying amounts of heparin showed similar size and shape properties, though surface charge decreased with an increase in the amount of heparin conjugation. The anticoagulant activity of the Hep-NS decreased by 65% compared to free heparin, however the Hep-NS retained their growth factor binding ability. Four different growth factors, bFGF, VEGF, BMP-2, and HGF were successfully encapsulated into Hep-NS. In vitro studies showed sustained release of all the growth factors for almost 60 days and the rate of release was directly dependent on the amount of heparin in Hep-NS. The released growth factors retained their bioactivity as assessed by a cell proliferation assay. This heparin nanosponge is therefore a promising nanocarrier for the loading and controlled release of growth factors.


Assuntos
Heparina/química , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Nanoestruturas/química , Animais , Proteína Morfogenética Óssea 2/metabolismo , Reagentes de Ligações Cruzadas/química , Preparações de Ação Retardada/química , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Nanopartículas , Nanoestruturas/uso terapêutico , Poloxâmero/química , Distribuição Tecidual
19.
Int. j. morphol ; 35(2): 733-739, June 2017. ilus
Artigo em Inglês | LILACS | ID: biblio-893047

RESUMO

Although, antineoplastic therapies have now been developed reduction of tumor progression,itis necessarytofind new therapeutic alternatives to suppress angiogenesis.Thus celecoxib (Cx) has been used for its antiangiogenic action in combination with certain polymeric compounds such as poly (lactic co-glycolic acid) (PLGA) acid, which help to improve the bioavailability and avoid effects of long drug administrations. For this purpose we used a murine tumor modelinduced by mammary adenocarcinoma cells resistant to chemotherapy (TA3-MTXR). CX/PLGA inhibits the microvascular density, VEGF expression and cell proliferationinaddition to increased apoptosis (P <0.0001). Cx reduces tumor progression in a concentration of 1000 ppm associated with PLGA, reducing cell proliferation, the presence of VEGF and promoting apoptosis of multiresistant TA3 tumor cells.


Si bien actualmente se han desarrollado terapias antineoplásicas que permiten reducir de cierta manera el avance tumoral, es necesario buscar nuevas alternativas terapéuticas que permitan suprimir la angiogénesis. Es así como el Celecoxib (Cx) ha sido utilizado por su acción antiangiogénica en combinación con algunos compuestos poliméricos, tal como el ácido poli (láctico co-glicólico) (PLGA), el cual ayudaría a mejorar la biodisponibilidad y evitaría efectos derivados de largas administraciones del fármaco. Para tal efecto se ha utilizado un modelo tumoral murino, inducido por células tumorales de adenocarcinoma mamario resistente a la quimioterapia (TA3-MTXR). Los resultados indican que CX/PLGA inhibe la microvascularización, expresión de VEGF y la proliferación celular además del aumento de la apoptosis (P<0,0001). El efecto antitumoral del Cx está bien reportado en la literatura; este sumado a la microencapsulación con PLGA, aportarían un sistema de administración útil, ya que nos otorga una administración sostenida en el tiempo, los cual podría ayudar a mantener los niveles de droga durante un período más prolongado, lo cual sería beneficioso en la terapia tumoral.


Assuntos
Animais , Feminino , Camundongos , Antineoplásicos/administração & dosagem , Celecoxib/administração & dosagem , Neovascularização Patológica/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Imuno-Histoquímica , Ácido Láctico/administração & dosagem , Invasividade Neoplásica/prevenção & controle , Ácido Poliglicólico/administração & dosagem , Polímeros/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos
20.
Int. j. morphol ; 35(1): 310-318, Mar. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-840971

RESUMO

La proteína morfogenética ósea (BMP), es una proteína endógena que ha mostrado efectos significativos en la promoción de la formación ósea. El uso de BMP ha sido descrito en la reconstrucción de defectos óseos de origen traumáticos y patológicos, incluyendo la fisura alveolar, el aumento de reborde alveolar, la elevación de seno maxilar, el injerto de alveolo post-extracción, y la cirugía perimplantaria entre otros. A pesar de las ventajas asociadas al uso de BMP y que en la actualidad se aplica en combinación con matrices de colágeno, ciertas propiedades tales como su baja resistencia mecánica y su elevada tasa de liberación inicial disminuyen su eficacia en la formación ósea. En este contexto, el desarrollo de nuevos sistemas de liberación prolongada de BMP que permitan la quimiotaxis de células mesenquimáticas y su posterior diferenciación a osteoblastos representa un desafío con alto potencial clínico para la estimulación de la formación ósea. En este trabajo, se describe el uso de BMP en la reconstrucción de fisuras alveolares y en particular se discuten las ventajas de su administración en micropartículas poliméricas comosistemas de liberación de BMP (rhBMP-2) con promisorias aplicaciones en la estimulación de la formación ósea.


Bone morphogenetic protein (BMP) is an endogenous protein that has shown significant effects in the promotion of bone formation. BMP also has been described in the reconstruction of traumatic and pathological bone defects, including alveolar cleft, alveolar ridge augmentation, maxillary sinus elevation, and applications in post-extraction alveolus graft, and peri-implant surgery among others. Despite the advantages associated with the use of BMP, currently is applied in combination with collagen matrices, which has certain properties such as low mechanical resistance and a high burst initial release that diminish its effectiveness in bone formation. In this context, the development of novel systems with greater mechanical resistance and prolonged release of BMP, that lead to chemotaxis of mesenchymal cells, following by its differentiation to osteoblasts represents a major challenge that holds outstanding clinical potential for the stimulation of bone formation. In this paper, we describe the use of BMP for the reconstruction of alveolar clefts, and its advantages being administrated in polymeric microparticles as sustain release system with promising applications in the stimulation of bone formation.


Assuntos
Humanos , Processo Alveolar/cirurgia , Proteína Morfogenética Óssea 2/uso terapêutico , Proteínas Morfogenéticas Ósseas/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Fissura Palatina/cirurgia , Nanopartículas
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