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1.
Int J Biol Macromol ; 259(Pt 2): 129210, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184039

RESUMO

Bone is a mineralized tissue with the intrinsic capacity for constant remodeling. Rapid prototyping techniques, using biomaterials that mimic the bone native matrix, have been used to develop osteoinductive and osteogenic personalized 3D structures, which can be further combined with drug delivery and phototherapy. Herein, a Fab@Home 3D Plotter printer was used to promote the layer-by-layer deposition of a composite mixture of gelatin, chitosan, tricalcium phosphate, and reduced graphene oxide (rGO). The phototherapeutic potential of the new NIR-responsive 3D_rGO scaffolds was assessed by comparing scaffolds with different rGO concentrations (1, 2, and 4 mg/mL). The data obtained show that the rGO incorporation confers to the scaffolds the capacity to interact with NIR light and induce a hyperthermy effect, with a maximum temperature increase of 16.7 °C after under NIR irradiation (10 min). Also, the increase in the rGO content improved the hydrophilicity and mechanical resistance of the scaffolds, particularly in the 3D_rGO4. Furthermore, the rGO could confer an NIR-triggered antibacterial effect to the 3D scaffolds, without compromising the osteoblasts' proliferation and viability. In general, the obtained data support the development of 3D_rGO for being applied as temporary scaffolds supporting the new bone tissue formation and avoiding the establishment of bacterial infections.


Assuntos
Fosfatos de Cálcio , Quitosana , Grafite , Alicerces Teciduais/química , Quitosana/química , Gelatina/química , Regeneração Óssea , Grafite/farmacologia , Grafite/química , Engenharia Tecidual/métodos
2.
Int J Biol Macromol ; 229: 224-235, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36586651

RESUMO

Asymmetric wound dressings have captured researchers' attention due to their ability to reproduce the structural and functional properties of the skin layers. Furthermore, recent studies also report the benefits of using near-infrared (NIR) radiation-activated photothermal therapies in treating infections and chronic wounds. Herein, a chitosan (CS) and reduced graphene oxide (rGO) hydrogel (CS_rGO) was combined with a polycaprolactone (PCL) and cellulose acetate (CA) electrospun membrane (PCL_CA) to create a new NIR-responsive asymmetric wound dressing. The rGO incorporation in the hydrogel increased the NIR absorption capacity and allowed a mild hyperthermy effect, a temperature increase of 12.4 °C when irradiated with a NIR laser. Moreover, the PCL_CA membrane presented a low porosity and hydrophobic nature, whereas the CS_rGO hydrogel showed the ability to provide a moist environment, prevent exudate accumulation and allow gaseous exchanges. Furthermore, the in vitro data demonstrate the capacity of the asymmetric structure to act as a barrier against bacteria penetration as well as mediating a NIR-triggered antibacterial effect. Additionally, human fibroblasts were able to adhere and proliferate in the CS_rGO hydrogel, even under NIR laser irradiation, presenting cellular viabilities superior to 90 %. Altogether, our data support the application of the NIR-responsive asymmetric wound dressings for skin regeneration.


Assuntos
Quitosana , Hipertermia Induzida , Nanofibras , Humanos , Quitosana/química , Hidrogéis/farmacologia , Hidrogéis/química , Nanofibras/química , Antibacterianos/farmacologia
3.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430620

RESUMO

Superparamagnetic nanoparticles are of high interest for therapeutic applications. In this work, nanoparticles of calcium-doped manganese ferrites (CaxMn1-xFe2O4) functionalized with citrate were synthesized through thermally assisted oxidative precipitation in aqueous media. The method provided well dispersed aqueous suspensions of nanoparticles through a one-pot synthesis, in which the temperature and Ca/Mn ratio were found to influence the particles microstructure and morphology. Consequently, changes were obtained in the optical and magnetic properties that were studied through UV-Vis absorption and SQUID, respectively. XRD and Raman spectroscopy studies were carried out to assess the microstructural changes associated with stoichiometry of the particles, and the stability in physiological pH was studied through DLS. The nanoparticles displayed high values of magnetization and heating efficiency for several alternating magnetic field conditions, compatible with biological applications. Hereby, the employed method provides a promising strategy for the development of particles with adequate properties for magnetic hyperthermia applications, such as drug delivery and cancer therapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Manganês , Cálcio , Hipertermia Induzida/métodos , Nanopartículas/química , Cálcio da Dieta , Campos Magnéticos , Estresse Oxidativo
4.
Nanomedicine (Lond) ; 17(27): 2057-2072, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36803049

RESUMO

Aims: To address the limitations of IR780 by preparing hydrophilic polymer-IR780 conjugates and to employ these conjugates in the assembly of nanoparticles (NPs) intended for cancer photothermal therapy. Materials & methods: The cyclohexenyl ring of IR780 was conjugated for the first time with thiol-terminated poly(2-ethyl-2-oxazoline) (PEtOx). This novel poly(2-ethyl-2-oxazoline)-IR780 (PEtOx-IR) conjugate was combined with D-α-tocopheryl succinate (TOS), leading to the assembly of mixed NPs (PEtOx-IR/TOS NPs). Results: PEtOx-IR/TOS NPs displayed optimal colloidal stability as well as cytocompatibility in healthy cells at doses within the therapeutic range. In turn, the combination of PEtOx-IR/TOS NPs and near-infrared light reduced heterotypic breast cancer spheroid viability to just 15%. Conclusion: PEtOx-IR/TOS NPs are promising agents for breast cancer photothermal therapy.


Conventional anticancer approaches are often associated with severe side effects. Herein, the authors assembled a novel nanoparticle whose therapeutic effect is triggered by laser light. In in vitro assays, the produced nanomaterial was able to, after interacting with laser light, reduce the viability of classic and advanced cancer models. In these conditions, but in the absence of laser light, no cytotoxicity was observed. In this way, the on-demand effect (triggered by laser light) may contribute to reduced side effects. Moreover, the produced nanoparticle revealed good stability, which is important for its future translation.


Assuntos
Neoplasias da Mama , Nanopartículas , Fotoquimioterapia , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Fototerapia , Nanopartículas/uso terapêutico , alfa-Tocoferol/uso terapêutico , Linhagem Celular Tumoral
5.
Nutrients ; 13(11)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34836018

RESUMO

Strength training increases systemic oxygen consumption, causing the excessive generation of reactive oxygen species, which in turn, provokes oxidative stress reactions and cellular processes that induce uterine contraction. The aim of this study was to evaluate the possible protective effect of Spirulina platensis (SP), an antioxidant blue algae, on the contractile and relaxation reactivity of rat uterus and the balance of oxidative stress/antioxidant defenses. Female Wistar rats were divided into sedentary (CG), trained (TG), and T + supplemented (TG50, TG100) groups. Reactivity was analyzed by AQCAD, oxidative stress was evaluated by the malondialdehyde (MDA) formation, and the antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Strength training increased contractile reactivity and decreased the pharmaco-mechanical component of relaxing reactivity in rat uterus. In addition, training decreased oxidation inhibition in the plasma and exercise increased oxidative stress in the uterine tissue; however, supplementation with algae prevented this effect and potentiated the increase in antioxidant capacity. Therefore, this study demonstrated that food supplementation prevents changes in reactivity and oxidative stress induced by strength training in a rat uterus, showing for the first time, that the uterus is a target for this exercise modality and antioxidant supplementation with S. platensis is an alternative means of preventing uterine dysfunction.


Assuntos
Antioxidantes/farmacologia , Condicionamento Físico Animal/efeitos adversos , Spirulina , Contração Uterina/efeitos dos fármacos , Doenças Uterinas/prevenção & controle , Animais , Suplementos Nutricionais , Feminino , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Doenças Uterinas/etiologia
6.
Oxid Med Cell Longev ; 2021: 3260789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367461

RESUMO

The consumption of hypercaloric diets is related to the development of obesity, favoring the etiology of gastrointestinal disorders. In this context, Spirulina platensis (SP), some blue-green algae with antioxidant action, appears as a potential therapeutic alternative to prevent obesity and associated intestinal disorders. Thus, the present study is aimed at evaluating the deleterious effects of the hypercaloric diet on the contractile and relaxing reactivity of the ileum of rats, as well as the possible preventive mechanisms of dietary supplementation with SP. Wistar rats were divided into three groups: fed a standard diet (SD), a hypercaloric diet (HCD), and/or supplemented with 25 mg/kg SP (HCD + SP25) for 8 weeks. The hypercaloric diet was effective in promoting obesity in rats, as well as decreasing potency and ileal relaxing and contractile efficacy. In contrast, dietary supplementation with SP was able to prevent some of the parameters of experimental obesity. In addition, SP prevented the reduction of intestinal reactivity, possibly due to a positive modulation of voltage-gated calcium channels (CaV) and negative regulation of muscarinic receptors (M3). Thus, food supplementation with Spirulina platensis becomes a promising alternative in the prevention of gastrointestinal diseases induced and/or aggravated by obesity.


Assuntos
Antioxidantes/farmacologia , Canais de Cálcio/metabolismo , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Obesidade/prevenção & controle , Receptor Muscarínico M3/metabolismo , Spirulina/fisiologia , Animais , Canais de Cálcio/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Ratos , Ratos Wistar , Receptor Muscarínico M3/genética , Spirulina/química
7.
Nanomedicine (Lond) ; 16(6): 453-464, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33660547

RESUMO

Aim: Enhance the colloidal stability and photothermal capacity of graphene oxide (GO) by functionalizing it with sulfobetaine methacrylate (SBMA)-grafted bovine serum albumin (BSA; i.e., SBMA-g-BSA) and by loading IR780, respectively. Materials & methods: SBMA-g-BSA coating and IR780 loading into GO was achieved through a simple sonication process. Results: SBMA-g-BSA-functionalized GO (SBMA-BSA/GO) presented an adequate size distribution and cytocompatibility. When in contact with biologically relevant media, the size of the SBMA-BSA/GO only increased by 8%. By loading IR780 into SBMA-BSA/GO, its photothermal capacity increased by twofold. The combination of near infrared light with SBMA-BSA/GO did not induce photocytotoxicity on breast cancer cells. In contrast, the interaction of IR780-loaded SBMA-BSA/GO with near infrared light caused the ablation of cancer cells. Conclusion: IR780-loaded SBMA-BSA/GO displayed an improved colloidal stability and phototherapeutic capacity.


Assuntos
Neoplasias da Mama/terapia , Betaína/análogos & derivados , Grafite , Indóis , Metacrilatos , Fototerapia
8.
Carbohydr Polym ; 254: 117236, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357844

RESUMO

The small amount of proteins in starch-rich food industry byproducts can be an advantage to crosslink with genipin and tailor the performance of biobased films. In this work, genipin was combined with non- purified starch recovered from industrial potato washing slurries and used for films production. Starch recovered from potato washing slurries contained 0.75% protein, 2 times higher than starch directly obtained from potato and 6 times higher than the commercial one. Starch protein-genipin networks were formed with 0.05% and 0.10% genipin, gelatinized at 75 °C and 95 °C in presence of 30% glycerol. Bluish colored films were obtained in all conditions, with the higher surface roughness (Ra, 1.22 µm), stretchability (elongation, 31%), and hydrophobicity (water contact angle, 127°) for 0.10% genipin and starch gelatinized at 75 °C. Therefore, starch-rich byproducts, when combined with genipin, are promising for surpassing the starch-based films hydrophilicity and mechanical fragilities while providing light barrier properties.


Assuntos
Iridoides/química , Amido/química , Biocombustíveis , Reagentes de Ligações Cruzadas , Indústria Alimentícia , Fenômenos Mecânicos , Microscopia de Força Atômica , Proteínas de Plantas/análise , Reologia , Solanum tuberosum/química , Solubilidade , Propriedades de Superfície , Suspensões
9.
Food Res Int ; 138(Pt A): 109733, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33292966

RESUMO

Food processing wastes together with the perishable foodstuff loss promote environmental and societal concerns. Food byproducts can have value as a source of functional molecules for developing active packaging without food waste, under a circular economy. Nevertheless, the often-associated extraction/chemical processes compromise the sustainability of food byproducts reusability. In this work, coffee silverskin (CS) and starch, recovered from coffee roasting and potato industries, respectively, were together gelatinized to form in-situ films. Targeting to fit with the food application requirements, it is important to understand the influence of crude CS amount (1%, 5%, and 10% w/w of dry starch weight) on potato starch-based film properties. CS conferred a brownish coloration to the films, maintaining their transparency. The films colour intensity, antioxidant activity, and water tolerance were directly related with the CS dosage. Moreover, as high the CS amount, higher the elasticity, stretchability, and UV radiation absorption of the pristine films. These data emphasized that CS molecules extracted during gelatinization prevented the starch-starch hydrogen bonding and conferred functional and barrier properties. Overall, adding crude CS during potato starch gelatinization revealed to be an efficient strategy to tune the performance of potato starch-based films, opening an opportunity for valorising coffee roasting and potato byproducts.


Assuntos
Eliminação de Resíduos , Solanum tuberosum , Antioxidantes , Café , Alimentos , Amido
10.
Curr Top Med Chem ; 20(25): 2300-2307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32819244

RESUMO

BACKGROUND: The increasing and inappropriate use of antibiotics has increased the number of multidrug-resistant microorganisms to these drugs, causing the emergence of infections that are difficult to control and manage by health professionals. As an alternative to combat these pathogens, some monoterpenes have harmful effects on the bacterial cell membrane, showing themselves as an alternative in combating microorganisms. Therefore, the positive enantiomer α -pinene becomes an alternative to fight bacteria, since it was able to inhibit the growth of the species Escherichia coli ATCC 25922, demonstrating the possibility of its use as an isolated antimicrobial or associated with other drugs. AIMS: The aim of this study is to evaluate the sensitivity profile of E. coli ATCC 25922 strain against clinical antimicrobials associated with (+) -α-pinene and how it behaves after successive exposures to subinhibitory concentrations of the phytochemicals. METHODS: The minimum inhibitory concentration (MIC) was determined using the microdilution method. The study of the modulating effect of (+) -α-pinene on the activity of antibiotics for clinical use in strains of E. coli and the analysis of the strain's adaptation to the monoterpene were tested using the adapted disk-diffusion method. RESULTS: The results demonstrate that the association of monoterpene with the antimicrobials ceftazidime, amoxicillin, cefepime, cefoxitin and amikacin is positive since it leads to the potentiation of the antibiotic effect of these compounds. It was observed that the monoterpene was able to induce crossresistance only for antimicrobials: cefuroxime, ceftazidime, cefepime and chloramphenicol. CONCLUSION: It is necessary to obtain more concrete data for the safe use of these combinations, paying attention to the existence of some type of existing toxicity reaction related to the herbal medicine and to understand the resistance mechanisms acquired by the microorganism.


Assuntos
Antibacterianos/farmacologia , Monoterpenos Bicíclicos/farmacologia , Escherichia coli/efeitos dos fármacos , Amicacina/química , Amicacina/farmacologia , Amoxicilina/química , Amoxicilina/farmacologia , Antibacterianos/química , Monoterpenos Bicíclicos/química , Cefepima/química , Cefepima/farmacologia , Cefoxitina/química , Cefoxitina/farmacologia , Ceftazidima/química , Ceftazidima/farmacologia , Testes de Sensibilidade Microbiana
11.
Oxid Med Cell Longev ; 2020: 3293065, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685091

RESUMO

Spirulina platensis, an important source of bioactive compounds, is a multicellular, filamentous cyanobacterium rich in high-quality proteins, vitamins, minerals, and antioxidants. Due to its nutrient composition, the alga is considered a complete food and is recognized for its anti-inflammatory, antioxidant, antiobesity, and reproprotective effects. All of which are important for prevention and treatment of organic and metabolic disorders such as obesity and erectile dysfunction. The aim of this study was to investigate the modulatory role of Spirulina platensis food supplementation and the mechanisms of action involved in reversing the damage caused by a hypercaloric diet on the erectile function of rats. The animals were divided into a standard diet group (SD, n = 5); a hypercaloric diet group (HCD, n = 5); a hypercaloric diet group supplemented with S. platensis at doses of 25 (HCD+SP25, n = 5), 50 (HCD+SP50, n = 5), and 100 mg/kg (HCD+SP100, n = 5); and a hypercaloric diet group subsequently fed a standard diet (HCD+SD, n = 5). In the rats fed a hypercaloric diet, dietary supplementation with S. platensis effectively increased the number of erections while decreasing latency to initiate penile erection. Additionally, S. platensis increases NO bioavailability, reduces inflammation by reducing the release of contractile prostanoids, enhances the relaxation effect promoted by acetylcholine (ACh), restores contractile reactivity damage and cavernous relaxation, reduces reactive oxygen species (ROS), and increases cavernous total antioxidant capacity (TAC). Food supplementation with S. platensis thus restores erectile function in obese rats, reduces production of contractile prostanoids, reduces oxidative stress, and increases NO bioavailability. Food supplementation with S. platensis thus emerges as a promising new therapeutic alternative for the treatment of erectile dysfunction as induced by obesity.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/normas , Disfunção Erétil/dietoterapia , Obesidade/complicações , Spirulina/química , Animais , Humanos , Masculino , Ratos
12.
Int J Biol Macromol ; 163: 251-259, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32615230

RESUMO

Agrofood byproducts may be exploited as a source of biomolecules suitable for developing bioplastic materials. In this work, the feasibility of using starch, oil, and waxes recovered from potato chips byproducts for films production was studied. The recovered potato starch-rich fraction (RPS) contained an amylopectin/amylose ratio of 2.3, gelatinization temperatures varying from 59 to 71 °C, and a gelatinization enthalpy of 12.5 J/g, similarly to a commercial potato starch (CPS). Despite of its spherical and oval granules identical to CPS, RPS had a more amorphous structure and gave rise to low viscous suspensions, contradicting the typical B-type polymorph crystal structure and sluggish dispersions of CPS, respectively. When used for films production, RPS originated transparent films with lower roughness and wettability than CPS-based films, but with higher stretchability. In turn, when combined with RPS and CPS, oil or waxes recovered from frying residues and potato peels, respectively, allowed to develop transparent yellowish RPS- and CPS-based films with increased surface hydrophobicity, mechanical traction resistance, elasticity, and/or plasticity. Therefore, potato chips industry byproducts revealed to have thermoplastic and hydrophobic biomolecules that can be used to efficiently develop biobased plastics with improved surface properties and flexibility, opening an opportunity for their valorization.


Assuntos
Filmes Comestíveis , Óleos de Plantas/química , Solanum tuberosum/química , Amido/química , Ceras/química , Amilopectina/química , Amilose/química , Fenômenos Químicos , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Tamanho da Partícula , Solubilidade
13.
Sci Rep ; 10(1): 6382, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286405

RESUMO

The purpose of this study was to evaluate the effects of Spirulina Platensis supplementation on selected blood markers of oxidative stress, muscle damage, inflammation, and performance in trained rats. Rats (250 g - 300 g) were submitted to a strength training program (eight weeks), divided into four groups: control (GT) (trained without supplementation), trained with daily-supplementation of 50 mg/kg (GT50), 150 mg/kg (GT150) and 500 mg/kg (GT500). Training consisted of a jump protocol in PVC-cylinder containing water, with increasing load over experimental weeks. We evaluated the markers of oxidative stress (malondialdehyde - MDA and antioxidant capacity) and inflammation (C-reactive protein) at the end of the training. Among groups submitted to strength training, concentration of C-reactive protein decreased after 8 weeks of intervention in the trained group and GT500. Strength training enhanced plasma MDA concentration of malondialdehyde with supplementation of S. platensis in GT150 and GT500. In plasma analysis, strength training enhanced the percentage of oxidation inhibition, with spirulina supplementation in rates of 150 and 500 mg/kg. Spirulina supplementation for 8 weeks (in a dose-effect manner) improved antioxidant capacity as well as attenuated exercise-induced increases in ROS and inflammation. As a practical application, the use as high doses did not cause a reduction in positive physiological adaptations to exercise training. Additional studies are necessary to test the application of Spirulina Platensis in other contexts, as collective sports (basketball, football, soccer).


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Estresse Oxidativo , Condicionamento Físico Animal , Spirulina , Animais , Biomarcadores/sangue , Inflamação , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/sangue
14.
Mar Drugs ; 18(2)2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013202

RESUMO

The blue alga Spirulina platensis has presented several pharmacological activities, highlighting its actions as an anti-inflammatory and antioxidant. In addition, there are few studies with the influence of strength training on physiological parameters, as intestinal contractility and oxidative cell damage. We evaluated the influence of S. platensis supplementation, strength training, and its association on contractile reactivity of rat ileum, as well as the balance of oxidative stress/antioxidant defenses. Methods: Male Wistar rats were divided into; sedentary (S); S + supplemented with algae at 50 (S50), 150 (S150), and 500 mg/kg (S500); trained (T); and T + supplemented (T50, T150, and T500). Contractile reactivity was analyzed by kymographs; oxidative stress on ileum by the malondialdehyde (MDA) formation; and the antioxidant capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. S. platensis supplementation reduced the reactivity of rat ileum to carbachol (CCh) and KCl, while training reduced only the CCh efficacy. In addition, association potentiated the reduction on contractile reactivity. Supplementation reduced the oxidative stress and increased oxidation inhibition; training alone did not alter this parameter, however association potentiated this beneficial effect. Therefore, this study demonstrated that both supplementation and its association with strength training promote beneficial effects regarding intestinal contractile reactivity and oxidative stress, providing new insights for intestinal disorders management.


Assuntos
Suplementos Nutricionais , Íleo/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Spirulina , Animais , Antioxidantes , Malondialdeído , Ratos , Ratos Wistar
15.
J Mater Chem B ; 8(6): 1256-1265, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31960003

RESUMO

Sustainably made, flexible and biocompatible composites, having environmentally friendly compositions and multifunctional capabilities, are promising materials for several emerging biomedical applications. Here, the development of flexible and multifunctional chitosan-based bionanocomposites with a mixed reduced graphene oxide-iron oxide (rGO-Fe3-xO4) filler is described. The filler is prepared by one-pot synthesis, ensuring good dispersibility of the Fe3-xO4 nanoparticles and rGO within the chitosan matrix during solvent casting. The resulting bionanocomposites present superparamagnetic response at room temperature. The antioxidant activity is 9 times higher than that of pristine chitosan. The mechanical properties of the films can be tuned from elastic (∼8 MPa) chitosan films to stiff (∼285 MPa) bionanocomposite films with 50% filler. The magnetic hyperthermia tests showed a temperature increase of 40 °C in 45 s for the 50% rGO-Fe3-xO4 film. Furthermore, the composites have no cytotoxicity to the nontumorigenic (HaCat) cell line, which confirms their biocompatibility and highlights the potential of these materials for biomedical applications, such as hyperthermia treatments.


Assuntos
Antioxidantes/química , Materiais Biocompatíveis/química , Quitosana/química , Hipertermia Induzida , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Compostos Férricos/química , Grafite/química , Humanos , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
16.
Colloids Surf B Biointerfaces ; 188: 110778, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945632

RESUMO

Gold-core mesoporous silica shell (AuMSS) nanorods unique physicochemical properties makes them versatile and promising nanomedicines for cancer photothermal therapy. Nevertheless, these nanomaterials present a reduced half-life in the blood and poor specificity towards the tumor tissue. Herein, d-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) and Hyaluronic Acid (HA) were combined for the first time to improve the AuMSS nanorods biological performance. The obtained results revealed that AuMSS surface functionalization induced the surface charge neutralization, from -28 ±â€¯10 mV to -3 ±â€¯5 mV and -10 ±â€¯4 mV for AuMSS-TPGS-HA (1:1) and (4:1) formulations, without impacting on nanomaterials' photothermal capacity. Moreover, the AuMSS functionalization improved the nanomaterials hemocompatibility and selectivity towards the cancer cells, particularly in the AuMSS-TPGS-HA (4:1) formulation. Furthermore, both formulations were able to mediate an on-demand photothermal effect, that induced the HeLa cancer cells death, confirming its potential for being applied as targeted multifunctional theragnostic nanomedicines.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Fototerapia , Antineoplásicos/química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Células HeLa , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Nanotubos/química , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Succinatos/química , Succinatos/farmacologia , Propriedades de Superfície , Vitamina E/química , Vitamina E/farmacologia
17.
J Mater Chem B ; 8(1): 45-64, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31764934

RESUMO

Supramolecular hydrogels are highly promising candidates as biomedical materials owing to their wide array of properties, which can be tailored and modulated. Additionally, their combination with plasmonic/magnetic nanoparticles to form plasmonic magnetogels further improves their potential in biomedical applications through the combination of complementary strategies, such as photothermia, magnetic hyperthermia, photodynamic therapy and magnetic-guided drug delivery. Here, a new dehydropeptide hydrogelator, Npx-l-Met-Z-ΔPhe-OH, was developed and combined with two different plasmonic/magnetic nanoparticle architectures, i.e., core/shell manganese ferrite/gold nanoparticles and gold-decorated manganese ferrite nanoparticles with ca. 55 nm and 45 nm sizes, respectively. The magnetogels were characterized via HR-TEM, FTIR spectroscopy, circular dichroism and rheological assays. The gels were tested as nanocarriers for a model antitumor drug, the natural compound curcumin. The incorporation of the drug in the magnetogel matrices was confirmed through fluorescence-based techniques (FRET, fluorescence anisotropy and quenching). The curcumin release profiles were studied with and without the excitation of the gold plasmon band. The transport of curcumin from the magnetogels towards biomembrane models (small unilamellar vesicles) was assessed via FRET between the fluorescent drug and the lipid probe Nile Red. The developed magnetogels showed promising results for photothermia and photo-triggered drug release. The magnetogels bearing gold-decorated nanoparticles showed the best photothermia properties, while the ones containing core/shell nanoparticles had the best photoinduced curcumin release.


Assuntos
Portadores de Fármacos/química , Nanopartículas Metálicas/química , Animais , Antineoplásicos/administração & dosagem , Curcumina/administração & dosagem , Compostos Férricos/química , Ouro/química , Hidrogéis/química , Compostos de Manganês/química , Camundongos , Neoplasias/tratamento farmacológico , Células RAW 264.7
18.
Oxid Med Cell Longev ; 2019: 7838149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772708

RESUMO

The possible mechanism is involved in the effects of Spirulina platensis on vascular reactivity. Animals were divided into sedentary group (SG) and sedentary groups supplemented with S. platensis at doses of 50 (SG50), 150 (SG150), and 500 mg/kg (SG500). To evaluate reactivity, cumulative concentration-response curves were constructed for phenylephrine and acetylcholine. To evaluate the involvement of the nitric oxide (NO) pathway, aorta tissue was preincubated with L-NAME and a new curve was then obtained for phenylephrine. Biochemical analyses were performed to evaluate nitrite levels, lipid peroxidation, and antioxidant activity. To contractile reactivity, only SG500 (pD2 = 5.6 ± 0.04 vs. 6.1 ± 0.06, 6.2 ± 0.02, and 6.2 ± 0.04) showed reduction in phenylephrine contractile potency. L-NAME caused a higher contractile response to phenylephrine in SG150 and SG500. To relaxation, curves for SG150 (pD2 = 7.0 ± 0.08 vs. 6.4 ± 0.06) and SG500 (pD2 = 7.3 ± 0.02 vs. 6.4 ± 0.06) were shifted to the left, more so in SG500. Nitrite was increased in SG150 and SG500. Lipid peroxidation was reduced, and oxidation inhibition was increased in all supplemented groups, indicating enhanced antioxidant activity. Chronic supplementation with S. platensis (150/500 mg/kg) caused a decrease in contractile response and increase in relaxation and nitrite levels, indicating greater NO production, due to decreased oxidative stress and increased antioxidant activity.


Assuntos
Antioxidantes/metabolismo , Aorta/efeitos dos fármacos , Óxido Nítrico/metabolismo , Spirulina/química , Animais , Suplementos Nutricionais , Ratos
19.
Crit Rev Anal Chem ; 49(1): 21-31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29757687

RESUMO

p-Coumaric acid (p-CA), also known as 4-hydroxycinnamic acid, is a phenolic acid, which has been widely studied due to its beneficial effects against several diseases and its wide distribution in the plant kingdom. This phenolic compound can be found in the free form or conjugated with other molecules; therefore, its bioavailability and the pathways via which it is metabolized change according to its chemical structure. p-CA has potential pharmacological effects because it has high free radical scavenging, anti-inflammatory, antineoplastic, and antimicrobial activities, among other biological properties. It is therefore essential to choose the most appropriate and effective analytical method for qualitative and quantitative determination of p-CA in different matrices, such as plasma, urine, plant extracts, and drug delivery systems. The most-reported analytical method for this purpose is high-performance liquid chromatography, which is mostly coupled with some type of detectors, such as UV/Vis detector. However, other analytical techniques are also used to evaluate this compound. This review presents a summary of p-CA in terms of its chemical and pharmacokinetic properties, pharmacological effects, drug delivery systems, and the analytical methods described in the literature that are suitable for its quantification.


Assuntos
Bebidas/análise , Técnicas de Química Analítica/métodos , Plantas/química , Propionatos/análise , Animais , Ácidos Cumáricos , Portadores de Fármacos/química , Humanos , Propionatos/química , Propionatos/farmacocinética , Propionatos/farmacologia
20.
Nanomedicine (Lond) ; 13(20): 2611-2627, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30334683

RESUMO

AIM: Develop a new poly-2-ethyl-2-oxazoline (PEOZ)-based coating for doxorubicin-loaded gold-core mesoporous silica shell (AuMSS) nanorods application in cancer chemo-photothermal therapy. METHODS: PEOZ functionalized AuMSS nanorods were obtained through the chemical grafting on AuMSS of a PEOZ silane derivative. RESULTS: The PEOZ chemical grafting on the surface of AuMSS nanorods allowed the neutralization of nanodevices' surface charge, from -30 to -15 mV, which improved nanoparticles' biocompatibility, namely by decreasing the blood hemolysis to negligible levels. In vitro antitumoral studies revealed that the combined treatment mediated by the PEOZ-coated AuMSS nanorods result in a synergistic effect, allowing the complete eradication of cervical cancer cells. CONCLUSION: The application of the PEOZ coating improves the AuMSS nanorods performance as a multifunctional combinatorial therapy for cervical cancer.


Assuntos
Nanopartículas/administração & dosagem , Nanotubos/química , Neoplasias/tratamento farmacológico , Poliaminas/administração & dosagem , Doxorrubicina/química , Ouro/química , Humanos , Nanopartículas/química , Neoplasias/patologia , Fototerapia , Poliaminas/química , Dióxido de Silício/química
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