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1.
Adv Sci (Weinh) ; 11(16): e2310012, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359060

RESUMEN

Natural evolution has nurtured a series of active molecules that play vital roles in physiological systems, but their further applications have been severely limited by rapid deactivation, short cycle time, and potential toxicity after isolation. For instance, the instability of structures and properties has greatly descended when sanshool is derived from Zanthoxylum xanthoxylum. Herein, natural polyphenols are employed to boost the key properties of sanshool by fabricating a series of nanoparticles (NPs). The intracellular evaluation and in vivo animal model are conducted to demonstrate the decreased photodamage score and skin-fold thickness of prepared NPs, which can be attributed to the better biocompatibility, improved free radical scavenging, down-regulated apoptosis ratios, and reduced DNA double-strand breaks compared to naked sanshool. This work proposes a novel strategy to boost the key properties of naturally occurring active molecules with the assistance of natural polyphenol-based platforms.


Asunto(s)
Polifenoles , Piel , Polifenoles/farmacología , Animales , Ratones , Piel/efectos de los fármacos , Piel/metabolismo , Nanopartículas/química , Zanthoxylum/química , Apoptosis/efectos de los fármacos , Extractos Vegetales/farmacología , Modelos Animales de Enfermedad , Humanos
2.
J Ethnopharmacol ; 323: 117699, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38185262

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Withania somnifera (L.) Dunal, known as Ashwagandha, has long been used in traditional medicine in Ayurveda, India, a representative adaptogen. The main active constituents of W. somnifera are withanolides, and the root is often used as a medicine with a wide range of pharmacological activities, which can be used to treat insomnia, neurasthenia, diabetes mellitus and skin cancer. AIM OF THE STUDY: Whole-component qualitative and quantitative analyses were performed on W. somnifera. We explored the ameliorative effect of the adaptogen representative plant W. somnifera on the senescence events of MGO-injured fibroblasts and its action mechanism and verified the hypotheses that WS can inhibit the accumulation of AGEs and regulate the dynamic balance among the components of the ECM by modulating the expression of integrin ß1 receptor; as a result, WS maintains cellular behavioural and biological functions in a normal range and retards the aging of skin from the cellular level. MATERIALS AND METHODS: In this study, the components of WS were first qualitatively and quantitatively analysed by HPLC fingerprinting and LC-MS detection. Second, a model of MGO-induced injury of CML-overexpressing fibroblasts was established. ELISA was used to detect CML expression and the synthesis of key extracellular matrix ECM protein components COL1, FN1, LM5 and TNC synthesis; CCK-8 was used to detect cell viability; EDU was used to detect cell proliferation capacity; fluorescence was used to detect cell adhesion capacity; and migration assay were used to detect cell migration capacity; qRT-PCR was used to detect the regulatory pathway TGF-ß1 and MMP-2, MMP-9 in ECMs; immunofluorescence was used to detect the expression of ITGB1; and WB was used to detect the expression of COL1, FN1, LM5, Tnc, TGF-ß1, MMP-2, MMP-9 and ITGB1. RESULTS: In total, 27 active ingredients were analysed from WS, which mainly consisted of withanolide components, such as withaferin A and withanolide A. Based on the model of MGO-induced fibroblast senescence injury, WS significantly inhibited CML synthesis. By up-regulating the expression of integrin ß1, it upregulated the expression of the TGF-ß1 gene, which is closely related to the generation of ECMs, downregulated the expression of the MMP-2 and MMP-9 genes, which are closely related to the degradation of ECMs, maintained the dynamic balance of the four types of ECMs, and improved cell viability as well as proliferation, migration and adhesion abilities. CONCLUSIONS: WS can prevent cellular behavioural dysfunction and delay skin ageing by reducing the accumulation of CML, upregulating the expression of the ITGB1 receptor, maintaining the normal function of ECM-integrin receptor interaction and preventing an imbalance between the production and degradation of protein components of ECMs. The findings reported in this study suggest that WS as a CML inhibitor can modulate ECM-integrin homeostasis and has great potential in the field of aging retardation.


Asunto(s)
Withania , Witanólidos , Factor de Crecimiento Transformador beta1/metabolismo , Withania/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Óxido de Magnesio/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Integrinas/metabolismo , Witanólidos/farmacología , Witanólidos/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/metabolismo , Fibroblastos/metabolismo , Matriz Extracelular/metabolismo , Raíces de Plantas/química
3.
Carbohydr Polym ; 287: 119331, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35422278

RESUMEN

Due to the rapid reaction kinetics, the morphology of chitosan/tripolyphosphate nanoparticles was difficult to control. We mixed chitosan and tripolyphosphate through a multi-inlet vortex mixer at different mixing efficiency and characteristic mixing time (τmix). Below a critical τmix, the aggregation of primary chitosan/TPP particles can be ceased. The corresponding aggregation time of primary particles (τagg) was dependent on the ionic strength, the degree of deacetylation and molecular weight of chitosan. Moreover, the particle compactness was estimated from the hydrodynamic diameter and the turbidity using a model based on the Mie theory. Slow and nonhomogeneous mixing led to more compact nanoparticles, while rapid and homogeneous mixing produced nanoparticles with a higher swelling ratio. Besides, the ionic strength and polymer concentration could affect the internal structure of nanoparticles. This study revealed the significance of mixing on the internal structure of chitosan/TPP nanoparticles, which could guide the preparation of other ionically-crosslinked polysaccharide colloids.


Asunto(s)
Quitosano , Nanopartículas , Quitosano/química , Coloides/química , Nanopartículas/química , Tamaño de la Partícula , Polifosfatos/química
4.
J Colloid Interface Sci ; 618: 185-195, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35338925

RESUMEN

Achieving a high encapsulation efficiency and loading capacity of proteins in lecithin-based liposomes has always been a challenge. Here, we use Flash Nano-Precipitation (FNP) to produce liposomes and investigated the encapsulation of model protein (Bovine Serum Albumin, BSA). Through rapid turbulent mixing, we obtained liposomes with small size, low polydispersity, and good batch repeatability at a high production rate. We demonstrated that the bilayer of liposomes prepared solely using lecithin was defective, which led to the fusion, and increased size and polydispersity. When cholesterol was added to reach a lecithin-to-cholesterol molar ratio of 5:3, a compact bilayer formed to effectively inhibit liposome fusion. The encapsulation efficiency and loading capacity of BSA was as high as âˆ¼ 68% and âˆ¼ 6% in lecithin-cholesterol liposome, respectively, far exceeding the values reported in the literature. Further study by Quartz Crystal Microbalance with Dissipation (QCM-D) revealed that the highly effective encapsulation was due to the rapid mutual adsorption between BSA and defective/curved lecithin double layers during the liposome formation. Such rapid mutual adsorption leads to the layer-by-layer assembly and formation of onion-like compact liposome structure as revealed by Cryo-TEM. This simple FNP method provides a scalable manufacturing approach for liposomes with efficient protein encapsulation. The revealed adsorption mechanism between protein and lecithin bilayers could also serve as a guide for similar studies.


Asunto(s)
Liposomas , Cebollas , Colesterol , Lecitinas , Liposomas/química , Albúmina Sérica Bovina/química
5.
Soft Matter ; 12(34): 7150-8, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27470971

RESUMEN

Nonionic surfactant-activated microgels (SAMs), composed of hydrophobic alkyl acrylates and hydrophilic hydroxyalkyl esters that utilize the effects of surfactant mediated swelling and interaction to provide pH-independent rheological properties, were previously reported as a new pathway to the rheology modification of surfactant solutions. Crosslinking was shown to play an important role in the properties of these soft microgel systems. To understand the impact of crosslinking chemistry on SAM polymers, we have compared two types of SAM polymers: a conventionally crosslinked SAM polymer via allyl pentaerythritol and a novel SAM polymer, where the surface is self-crosslinked via a reactive surfactant. We have systematically characterized the polymer's swelling, rheology and microstructure in a model system containing the polymer, sodium dodecyl sulfate (SDS) and water. Surface self-crosslinking is demonstrated to be a more effective crosslinking approach to create surfactant-mediated interactions between the microgel particles, resulting in more effective rheology modification. Internal crosslinking hinders both the full swelling of the SAM polymer as well as inter-particle bridging interactions, and is therefore less effective. To our best knowledge, this is the first report on creating a novel surface self-crosslinked microgel via a dual-functional reactive surfactant that interacts with a non-reactive surfactant to create a yield stress fluid.

6.
J Am Chem Soc ; 135(46): 17547-55, 2013 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-24160889

RESUMEN

Oppositely charged polyelectrolyte-surfactant mixtures are ubiquitous in biology and the basis of numerous consumer healthcare products. Despite their broad use, however, a rational approach to their formulation remains challenging because of the complicated association mechanisms. Through compilation and analysis of literature reports and our own research, we have developed a semiempirical correlation of the binding strength of surfactants to polyelectrolytes in salt-free mixtures as a function of the polyion linear charge density and the surfactant hydrophobicity. We have found that the cooperative binding strength increases as the square of the polyelectrolyte's linear charge density and in proportion to the surfactant's hydrophobicity, such that a quantitative relationship holds across a broad range of polyelectrolytes. Deviations from the correlation reveal the role of system-specific interactions not considered in the analysis. This engineering relationship aids in the rational design of oppositely charged polyelectrolyte-surfactant formulations for consumer products and biomedicines by enabling the prediction of binding strengths in polyelectrolyte-surfactant mixtures based on mesoscale parameters determined from the chemical composition.

7.
J Am Chem Soc ; 134(51): 20728-32, 2012 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-23030359

RESUMEN

The search for stable vesicular structures is a long-standing topic of research because of the usefulness of these structures and the scarcity of surfactant systems that spontaneously form vesicles in true thermodynamic equilibrium. We report the first experimental evidence of spontaneous formation of vesicles for a pure cationic double tail surfactant (didodecyldimethylammonium bromide, DDAB) in a protic ionic liquid (ethylammonium nitrate, EAN). Using small and ultra-small angle neutron scattering, rheology and bright field microscopy, we identify the coexistence of two vesicle containing phases in compositions ranging from 2 to 68 wt %. A low density highly viscous solution containing giant vesicles (D ~ 30 µm) and a sponge (L(3)) phase coexists with a dilute high density phase containing large vesicles (D ~ 2.5 µm). Vesicles form spontaneously via different thermodynamic routes, with the same size distribution, which strongly supports that they exist in a true thermodynamic equilibrium. The formation of equilibrium vesicles and the L(3) phase is facilitated by ion exchange between the cationic surfactant and the ionic liquid, as well as the strength of the solvophobic effect in the protic ionic liquid.

8.
Langmuir ; 28(28): 10348-62, 2012 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-22769434

RESUMEN

Coacervation in mixtures of polyelectrolytes and surfactants with opposite charge is common in nature and is also technologically important to consumer health care products. To understand the complexation behavior of these systems better, we combine multiple experimental techniques to systematically study the polymer/surfactant binding interactions and the phase behavior of anionic sodium dodecyl sulfate (SDS) surfactant in cationic JR 400 polymer aqueous solutions. The phase-behavior study resolves a discrepancy in the literature by identifying a metastable phase between the differing redissolution phase boundaries reported in the literature for the surfactant-rich regime. Isothermal titration calorimetry analyzed within the framework of the simple Satake-Yang model identifies binding parameters for the surfactant-lean phase, whereas a calculation for polymer-bound micelles coexisting with free micelles is analyzed in the surfactant-rich redissolution regime. This analysis provides a preliminary understanding of the interactions governing the observed phase behavior. The resulting thermodynamic properties, including binding constants and the molar Gibbs free energies, enthalpies, and entropies, identify the relative importance of both hydrophobic and electrostatic interactions and provide a first approximation for the corresponding microstructures in the different phases. Our study also addresses the stability and metastability of oppositely charged polyelectrolytes and surfactant mixtures.


Asunto(s)
Polietilenglicoles/química , Polímeros/química , Compuestos de Amonio Cuaternario/química , Dodecil Sulfato de Sodio/química , Tensoactivos/química , Termodinámica , Aniones/química , Cationes/química , Electrólitos/química , Estructura Molecular
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