Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 10.281
Filtrar
1.
ACS Appl Mater Interfaces ; 13(33): 39142-39156, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433244

RESUMO

The reconstruction of the intra/interfibrillar mineralized collagen microstructure is extremely important in biomaterial science and regeneration medicine. However, certain problems, such as low efficiency and long period of mineralization, are apparent, and the mechanism of interfibrillar mineralization is often neglected in the present literature. Thus, we propose a novel model of biomimetic collagen mineralization that uses molecules with the dual function of cross-linking collagen and regulating collagen mineralization to construct the intrafibrillar and interfibrillar collagen mineralization of the structure of mineralized collagen hard tissues. In the present study completed in vitro, N-2-(3,4-dihydroxyphenyl) acrylamide (DAA) is used to bind and cross-link collagen molecules and further stabilize the self-assembled collagen fibers. The DAA-collagen complex provides more affinity with calcium and phosphate ions, which can reduce the calcium phosphate/collagen interfacial energy to promote hydroxyapatite (HA) nucleation and accelerate the rate of collagen fiber mineralization. Besides inducing intrafibrillar mineralization, the DAA-collagen complex mineralization template can realize interfibrillar mineralization with the c-axis of the HA crystal on the surface of collagen fibers and between fibers that are parallel to the long axis of collagen fibers. The DAA-collagen complex, as a new type of mineralization template, may provide a new collagen mineralization strategy to produce a mineralized scaffold material for tissue engineering or develop bone-like materials.


Assuntos
Acrilamida/química , Materiais Biomiméticos/química , Colágeno/química , Dopamina/química , Osso e Ossos , Cálcio/química , Cálcio/metabolismo , Fosfatos de Cálcio/química , Reagentes para Ligações Cruzadas/química , Cristalização , Durapatita/química , Durapatita/metabolismo , Matriz Extracelular/metabolismo , Humanos , Simulação de Dinâmica Molecular , Polimerização , Medicina Regenerativa , Propriedades de Superfície , Engenharia Tecidual
2.
J Chem Phys ; 155(7): 075102, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418922

RESUMO

In this paper, we have studied the vibrational spectral features for the collagen triple helix using a dispersion corrected hybrid density functional theory (DFT-D) approach. The protein is simulated by an infinite extended polymer both in the gas phase and in a water micro-solvated environment. We have adopted proline-rich collagen models in line with the high content of proline in natural collagens. Our scaled harmonic vibrational spectra are in very good agreement with the experiments and allow for the peak assignment of the collagen amide I and III bands, supporting or questioning the experimental interpretation by means of vibrational normal modes analysis. Furthermore, we demonstrated that IR spectroscopy in the THz region can detect the small variations inherent to the triple helix helicity (10/3 over 7/2), thus elucidating the packing state of the collagen. So far, identifying the collagen helicity is only possible by means of crystal x-ray diffraction.


Assuntos
Amidas/química , Colágeno/química , Teoria da Densidade Funcional , Modelos Moleculares , Prolina/química , Conformação Proteica em alfa-Hélice , Solventes/química , Vibração
3.
Nutrients ; 13(8)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34444880

RESUMO

Osteoarthritis (OA), the most common form of arthritis, is associated with metabolic diseases and gut microbiome dysbiosis. OA patients often take supplements of collagen hydrolysates (CHs) with a high peptide content. Following digestion, some peptides escape absorption to induce prebiotic effects via their colonic fermentation to generate short-chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs) and colonic gases (NH4 and H2S). The capacity of CHs to generate microbial metabolites is unknown. Proteomic analysis of two CHs (CH-GL and CH-OPT) demonstrated different native peptide profiles with increased peptide diversity after in vitro gastric and small intestinal digestion. Subsequent 24 h fermentation of the CH digests in a dynamic gastrointestinal (GI) digestion model containing human fecal matter showed that CH-OPT increased (p < 0.05) H2S, SCFAs (propionic, butyric and valeric acids), BCFAs, and decreased NH4 in the ascending colon reactor with no major changes seen with CH-GL. No major effects were observed in the transverse and descending vessels for either CH. These findings signify that CHs can induce prebiotic effects in the ascending colon that are CH dependent. More studies are needed to determine the physiological significance of CH-derived colonic metabolites, in view of emerging evidence connecting the gut to OA and metabolic diseases.


Assuntos
Colágeno/química , Fermentação , Microbioma Gastrointestinal , Peptídeos/análise , Hidrolisados de Proteína/metabolismo , Animais , Colo/metabolismo , Colo/microbiologia , Digestão/fisiologia , Humanos , Modelos Biológicos , Proteômica
4.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445258

RESUMO

Collagenases are essential enzymes capable of digesting triple-helical collagen under physiological conditions. These enzymes play a key role in diverse physiological and pathophysiological processes. Collagenases are used for diverse biotechnological applications, and it is thus of major interest to identify new enzyme variants with improved characteristics such as expression yield, stability, or activity. The engineering of new enzyme variants often relies on either rational protein design or directed enzyme evolution. The latter includes screening of a large randomized or semirational genetic library, both of which require an assay that enables the identification of improved variants. Moreover, the assay should be tailored for microplates to allow the screening of hundreds or thousands of clones. Herein, we repurposed the previously reported fluorogenic assay using 3,4-dihydroxyphenylacetic acid for the quantitation of collagen, and applied it in the detection of bacterial collagenase activity in bacterial lysates. This enabled the screening of hundreds of E. coli colonies expressing an error-prone library of collagenase G from C. histolyticum, in 96-well deep-well plates, by measuring activity directly in lysates with collagen. As a proof-of-concept, a single variant exhibiting higher activity than the starting-point enzyme was expressed, purified, and characterized biochemically and computationally. This showed the feasibility of this method to support medium-high throughput screening based on direct evaluation of collagenase activity.


Assuntos
Proteínas de Bactérias , Clostridium histolyticum/genética , Colágeno/química , Evolução Molecular Direcionada , Escherichia coli/enzimologia , Colagenase Microbiana , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Clostridium histolyticum/enzimologia , Escherichia coli/genética , Colagenase Microbiana/química , Colagenase Microbiana/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
5.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443477

RESUMO

Here, the hierarchical assembly of a collagen mimetic peptide (CMP) displaying four bipyridine moieties is described. The CMP was capable of forming triple helices followed by self-assembly into disks and domes. Treatment of these disks and domes with metal ions such as Fe(II), Cu(II), Zn(II), Co(II), and Ru(III) triggered the formation of microcages, and micron-sized cup-like structures. Mechanistic studies suggest that the formation of the microcages proceeds from the disks and domes in a metal-dependent fashion. Fluorescently-labeled dextrans were encapsulated within the cages and displayed a time-dependent release using thermal conditions.


Assuntos
Materiais Biomiméticos/química , Colágeno/química , Metais/química , Peptídeos/química , Dextranos/química , Íons/química , Ligantes , Estrutura Molecular
6.
Nat Chem Biol ; 17(8): 865-871, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34253910

RESUMO

Collagens are fibrous proteins that are integral to the strength and stability of connective tissues. During collagen maturation, lysyl oxidases (LOX) initiate the cross-linking of fibers, but abnormal LOX activity is associated with impaired tissue function as seen in fibrotic and malignant diseases. Visualizing and targeting this dynamic process in healthy and diseased tissue is important, but so far not feasible. Here we present a probe for the simultaneous monitoring and targeting of LOX-mediated collagen cross-linking that combines a LOX-activity sensor with a collagen peptide to chemoselectively target endogenous aldehydes generated by LOX. This synergistic probe becomes covalently anchored and lights up in vivo and in situ in response to LOX at the sites where cross-linking occurs, as demonstrated by staining of normal skin and cancer sections. We anticipate that our reactive collagen-based sensor will improve understanding of collagen remodeling and provide opportunities for the diagnosis of fibrotic and malignant diseases.


Assuntos
Colágeno/metabolismo , Reagentes para Ligações Cruzadas/metabolismo , Peptídeos/metabolismo , Proteína-Lisina 6-Oxidase/metabolismo , Aldeídos/química , Aldeídos/metabolismo , Animais , Colágeno/química , Reagentes para Ligações Cruzadas/química , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Peptídeos/química , Proteína-Lisina 6-Oxidase/química
7.
Int J Mol Sci ; 22(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207766

RESUMO

Human-induced pluripotent stem cells (hiPSCs) can be applied in patient-specific cell therapy to regenerate lost tissue or organ function. Anisotropic control of the structural organization in the newly generated bone matrix is pivotal for functional reconstruction during bone tissue regeneration. Recently, we revealed that hiPSC-derived osteoblasts (hiPSC-Obs) exhibit preferential alignment and organize in highly ordered bone matrices along a bone-mimetic collagen scaffold, indicating their critical role in regulating the unidirectional cellular arrangement, as well as the structural organization of regenerated bone tissue. However, it remains unclear how hiPSCs exhibit the cell properties required for oriented tissue construction. The present study aimed to characterize the properties of hiPSCs-Obs and those of their focal adhesions (FAs), which mediate the structural relationship between cells and the matrix. Our in vitro anisotropic cell culture system revealed the superior adhesion behavior of hiPSC-Obs, which exhibited accelerated cell proliferation and better cell alignment along the collagen axis compared to normal human osteoblasts. Notably, the oriented collagen scaffold stimulated FA formation along the scaffold collagen orientation. This is the first report of the superior cell adhesion behavior of hiPSC-Obs associated with the promotion of FA assembly along an anisotropic scaffold. These findings suggest a promising role for hiPSCs in enabling anisotropic bone microstructural regeneration.


Assuntos
Colágeno/química , Adesões Focais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Osteoblastos/metabolismo , Tecidos Suporte/química , Humanos
8.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202795

RESUMO

It is a significant challenge for a titanium implant, which is a bio-inert material, to recruit osteogenic factors, such as osteoblasts, proteins and blood effectively when these are contained in a biomaterial. The objective of this study was to examine the effect of ultraviolet (UV)-treatment of titanium on surface wettability and the recruitment of osteogenic factors when they are contained in an atelocollagen sponge. UV treatment of a dental implant made of commercially pure titanium was performed with UV-light for 12 min immediately prior to the experiments. Superhydrophilicity on dental implant surfaces was generated with UV-treatment. The collagen sponge containing blood, osteoblasts, or albumin was directly placed on the dental implant. Untreated implants absorbed only a little blood from the collagen sponge, while the UV-treated implants absorbed blood rapidly and allowed it to spread widely, almost over the entire implant surface. Blood coverage was 3.5 times greater for the UV-treated implants (p < 0.001). Only 6% of the osteoblasts transferred from the collagen sponge to the untreated implants, whereas 16% of the osteoblasts transferred to the UV-treated implants (p < 0.001). In addition, a weight ratio between transferred albumin on the implant and measured albumin adsorbed on the implant was 17.3% in untreated implants and 38.5% in UV-treated implants (p < 0.05). These results indicated that UV treatment converts a titanium surface into a superhydrophilic and bio-active material, which could recruite osteogenic factors even when they were contained in a collagen sponge. The transfer and subsequent diffusion and adsorption efficacy of UV-treated titanium surfaces could be useful for bone formation when titanium surfaces and osteogenic factors are intervened with a biomaterial.


Assuntos
Materiais Biocompatíveis , Colágeno , Osteogênese , Titânio , Raios Ultravioleta , Adsorção , Albuminas , Animais , Materiais Biocompatíveis/química , Colágeno/química , Implantes Dentários , Difusão , Interações Hidrofóbicas e Hidrofílicas , Osseointegração , Osteoblastos/citologia , Osteoblastos/metabolismo , Propriedades de Superfície , Titânio/química , Molhabilidade
9.
Int J Nanomedicine ; 16: 3803-3818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113101

RESUMO

Background: Effective repair of full-thickness abdominal wall defects requires a patch with sufficient mechanical strength and anti-adhesion characteristics to avoid the formation of hernias and intra-abdominal complications such as intestinal obstruction and fistula. However, patches made from polymers or bio-derived materials may not meet these requirements and lack the bionic characteristics of the abdominal wall. Materials and Methods: In this study, we report a consecutive electrospun method for preparing a double-layer structured nanofiber membrane (GO-PCL/CS-PCL) using polycaprolactone (PCL), graphene oxide (GO) and chitosan (CS). To expand the bio-functions (angiogenesis/reducing reactive oxygen species) of the patch (GO-PCL/NAC-CS-PCL), N-acetylcysteine (NAC) was loaded for the repair of full-thickness abdominal wall defects (2×1.5cm) in rat model. Results: The double-layered patch (GO-PCL/NAC-CS-PCL) showed excellent mechanical strength and biocompatibility. After 2 months, rats treated with the patch exhibited the desired repair effect with no hernia formation, less adhesion (adhesion score: 1.50±0.50, P<0.001) and more collagen deposition (percentage of collagen deposition: 34.94%±3.31%, P<0.001). Conclusion: The double-layered nanomembranes presented in this study have good anti-hernia and anti-adhesion effects, as well as improve the microenvironment in vivo. It, therefore, holds good prospects for the repair of abdominal wall defects and provides a promising key as a postoperative anti-adhesion agent.


Assuntos
Parede Abdominal/anormalidades , Quitosana/química , Grafite/química , Hérnia/tratamento farmacológico , Nanofibras/administração & dosagem , Poliésteres/administração & dosagem , Aderências Teciduais/tratamento farmacológico , Animais , Colágeno/química , Hérnia/etiologia , Hérnia/patologia , Masculino , Nanofibras/química , Poliésteres/química , Ratos , Ratos Sprague-Dawley , Aderências Teciduais/etiologia , Aderências Teciduais/patologia
10.
ACS Appl Mater Interfaces ; 13(24): 28764-28773, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34110763

RESUMO

Titanium is widely utilized for manufacturing medical implants due to its inherent mechanical strength and biocompatibility. Recent studies have focused on developing coatings to impart unique properties to Ti implants, such as antimicrobial behavior, enhanced cell adhesion, and osteointegration. Ca- and Si-based ceramic (CS) coatings can enhance bone integration through the release of Ca and Si ions. However, high degradation rates of CS ceramics create a basic environment that reduces cell viability. Polymeric or protein-based coatings may be employed to modulate CS degradation. However, it is challenging to ensure coating stability over extended periods of time without compromising biocompatibility. In this study, we employed a fluorous-cured collagen shell as a drug-loadable scaffold around CS nanorod coatings on Ti implants. Fluorous-cured collagen coatings have enhanced mechanical and enzymatic stability and are able to regulate the release of Ca and Si ions. Furthermore, the collagen scaffold was loaded with antimicrobial peptides to impart antimicrobial activity while promoting cell adhesion. These multifunctional collagen coatings simultaneously regulate the degradation of CS ceramics and enhance antimicrobial activity, while maintaining biocompatibility.


Assuntos
Antibacterianos/farmacologia , Nanotubos/química , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Silicatos/química , Titânio/química , Cicatrização/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/toxicidade , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/toxicidade , Colágeno/química , Colágeno/toxicidade , Humanos , Testes de Sensibilidade Microbiana , Nanotubos/toxicidade , Osteoblastos/efeitos dos fármacos , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/toxicidade , Silicatos/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Titânio/toxicidade , Molhabilidade
11.
Molecules ; 26(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062818

RESUMO

Salivary gland stem cells (SGSCs) are potential cell sources for the treatment of salivary gland diseases. The control of cell survival is an essential factor for applying stem cells to regenerative medicine or stem cell-based research. The purpose of this study was to investigate the effects of the ROCK inhibitor Y-27632 on the survival of SGSCs and its underlying mechanisms. SGSCs were isolated from mouse submandibular glands and cultured in suspension. Treatment with Y-27632 restored the viability of SGSCs that was significantly decreased during isolation and the subsequent culture. Y-27632 upregulated the expression of anti-apoptotic protein BCL-2 in SGSCs and, in the apoptosis assay, significantly reduced apoptotic and necrotic cell populations. Matrigel was used to mimic the extracellular environment of an intact salivary gland. The expression of genes regulating apoptosis and the ROCK signaling pathway was significantly reduced when SGSCs were embedded in Matrigel. SGSCs cultured in Matrigel and treated with Y-27632 showed no difference in the total numbers of spheroids and expression levels of apoptosis-regulating genes. Matrigel-embedded SGSCs treated with Y-27632 increased the number of spheroids with budding structures and the expression of acinar cell-specific marker AQP5. We demonstrate the protective effects of Y-27632 against dissociation-induced apoptosis of SGSCs during their culture in vitro.


Assuntos
Amidas/farmacologia , Piridinas/farmacologia , Glândulas Salivares/efeitos dos fármacos , Quinases Associadas a rho/antagonistas & inibidores , Animais , Apoptose , Morte Celular , Sobrevivência Celular , Células Cultivadas , Colágeno/química , Combinação de Medicamentos , Matriz Extracelular/metabolismo , Feminino , Laminina/química , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Necrose , Proteoglicanas/química , Esferoides Celulares , Células-Tronco/citologia , Glândula Submandibular/efeitos dos fármacos
12.
Int J Biol Macromol ; 185: 77-86, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34139244

RESUMO

Nanostructure provides a closer structural support approximation to native bone architecture for cells and further regulates cell's behavior, resulting in the formation of functional tissues. In this work, three engineering collagen templates with oriented fiber architectures were fabricated via electrospinning (Es), plastic compression and tensile (PCT), and dynamic shear stress (SS) methods. Under the observation of POM, SEM, AFM and TEM, the PCT-template and SS-template are packed with well-oriented nanofibers with the native collagen architecture of 67 nm D-periodicity, and the mechanical properties conferred to the templates are better than that of the Es-template. When mentioning the cell's behavior, MC3T3-E1 adhered to grow along the alignment of collagen fiber orientation when cultured on the PCT-template and SS-template. The SS-template with nano- and micro-ordered architecture guided cells to stretch their plasma along with the orientation of collagen fiber, produce more aligned Type I collagen fibers and promote significantly higher osteogenic differentiation of MC3T3-E1 than the PCT-template and Es-template. Overall, it is strongly argued the feasibility of hierarchical collagen fiber architectures for bone tissue regeneration.


Assuntos
Colágeno/química , Osteoblastos/citologia , Engenharia Tecidual/métodos , Células 3T3 , Animais , Diferenciação Celular , Proliferação de Células , Camundongos , Nanofibras/química , Osteogênese , Ratos , Estresse Mecânico , Tecidos Suporte
13.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073402

RESUMO

The development of scaffolds mimicking the extracellular matrix containing bioactive substances has great potential in tissue engineering and wound healing applications. This study investigates melatonin-a methoxyindole present in almost all biological systems. Melatonin is a bioregulator in terms of its potential clinical importance for future therapies of cutaneous diseases. Mammalian skin is not only a prominent melatonin target, but also produces and rapidly metabolizes the multifunctional methoxyindole to biologically active metabolites. In our methodology, chitosan/collagen (CTS/Coll)-contained biomaterials are blended with melatonin at different doses to fabricate biomimetic hybrid scaffolds. We use rat tail tendon- and Salmo salar fish skin-derived collagens to assess biophysical and cellular properties by (i) Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), (ii) thermogravimetric analysis (TG), (iii) scanning electron microscope (SEM), and (iv) proliferation ratio of cutaneous cells in vitro. Our results indicate that melatonin itself does not negatively affect biophysical properties of melatonin-immobilized hybrid scaffolds, but it induces a pronounced elevation of cell viability within human epidermal keratinocytes (NHEK), dermal fibroblasts (NHDF), and reference melanoma cells. These results demonstrate that this indoleamine accelerates re-epithelialization. This delivery is a promising technique for additional explorations in future dermatotherapy and protective skin medicine.


Assuntos
Bandagens , Quitosana/química , Colágeno/química , Derme/metabolismo , Epiderme/metabolismo , Fibroblastos/metabolismo , Queratinócitos/metabolismo , Melatonina , Linhagem Celular , Derme/patologia , Avaliação Pré-Clínica de Medicamentos , Epiderme/patologia , Fibroblastos/patologia , Humanos , Queratinócitos/patologia , Melatonina/química , Melatonina/farmacocinética , Melatonina/farmacologia
14.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070436

RESUMO

The aim was to examine the efficiency of a scaffold made of poly (L-lactic acid)-co-poly(ϵ-caprolactone), collagen (COL), polyaniline (PANI), and enriched with adipose-derived stem cells (ASCs) as a nerve conduit in a rat model. P(LLA-CL)-COL-PANI scaffold was optimized and electrospun into a tubular-shaped structure. Adipose tissue from 10 Lewis rats was harvested for ASCs culture. A total of 28 inbred male Lewis rats underwent sciatic nerve transection and excision of a 10 mm nerve trunk fragment. In Group A, the nerve gap remained untouched; in Group B, an excised trunk was used as an autograft; in Group C, nerve stumps were secured with P(LLA-CL)-COL-PANI conduit; in Group D, P(LLA-CL)-COL-PANI conduit was enriched with ASCs. After 6 months of observation, rats were sacrificed. Gastrocnemius muscles and sciatic nerves were harvested for weight, histology analysis, and nerve fiber count analyses. Group A showed advanced atrophy of the muscle, and each intervention (B, C, D) prevented muscle mass decrease (p < 0.0001); however, ASCs addition decreased efficiency vs. autograft (p < 0.05). Nerve fiber count revealed a superior effect in the nerve fiber density observed in the groups with the use of conduit (D vs. B p < 0.0001, C vs. B p < 0.001). P(LLA-CL)-COL-PANI conduits with ASCs showed promising results in managing nerve gap by decreasing muscle atrophy.


Assuntos
Modelos Animais de Doenças , Células-Tronco Mesenquimais/metabolismo , Nanofibras/química , Regeneração Nervosa , Neurogênese , Traumatismos dos Nervos Periféricos/terapia , Nervo Isquiático/metabolismo , Tecidos Suporte/química , Compostos de Anilina/química , Animais , Caproatos/química , Células Cultivadas , Colágeno/química , Imuno-Histoquímica , Lactonas/química , Masculino , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Microscopia Eletrônica de Varredura , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Nanofibras/ultraestrutura , Traumatismos dos Nervos Periféricos/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Poliésteres/química , Ratos , Ratos Endogâmicos Lew , Nervo Isquiático/citologia , Nervo Isquiático/patologia , Transplante Autólogo
15.
Food Chem ; 360: 130068, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34029925

RESUMO

Collagen Type I derived from fish is mainly limited by its poor physicochemical properties for further applications. In this study, we developed epigallocatechin gallate (EGCG) cross-linked collagen hydrogels (EC hydrogels) to realize physicochemical improvements, basing on the interaction mechanism between collagen and EGCG. The integrity of collagen framework with slight secondary structure change in the presence of EGCG was confirmed. The stronger stability of collagen fibrils was proved by slower swelling ratio, declined enzymatic degradation, improved thermal analysis and mechanical test due to EGCG modification. To illustrate the potential mechanism between collagen and EGCG, molecular docking was used to identify both covalent (CN bond, between lysine of collagen and C2-ring B of EGCG) and non-covalent bonds (hydrogen bond and hydrophobic interaction) within in EC hydrogel. Taken together, this work would offer some insights into the further study about the interaction between EGCG and collagen.


Assuntos
Catequina/análogos & derivados , Colágeno/química , Hidrogéis/química , Animais , Catequina/química , Catequina/metabolismo , Colágeno/metabolismo , Hidrogéis/metabolismo , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Reologia , Eletricidade Estática , Temperatura de Transição
16.
Food Chem ; 361: 130079, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34033991

RESUMO

Enzymatic tenderisation including bromelain enhances underused cuts of meat in emerged restructuring technology. Physicochemical and textural characteristics of restructured pork steak hydrolysed with bromelain for masticatory dysfunction people were evaluated. Restructured pork steak treated with bromelain at 0.05 and 0.1% (w/w) was hydrolysed at 50 °C for 0, 3, 6, 9 and 12 min. The cooking losses of 0.05% (w/w) bromelain for 0, 3 and 6 min were lower than 0.1% (w/w) bromelain samples. The ΔE increased after increasing the enzyme concentration and hydrolysis time. Bromelain-treated samples at higher concentrations showed lower WBSF, KSF and TPA parameters, but cohesiveness of 0.05% (w/w) had higher than 0.1% (w/w) bromelain samples. Total protein, sarcoplasmic protein solubility, TCA-soluble peptide, total collagen and soluble collagen contents were the highest in 0.1% (w/w) bromelain-treated samples for 12 min (P < 0.05). According to SDS-PAGE and SEM, various proteins in the enzyme-treated samples were degraded.


Assuntos
Bromelaínas/química , Carne de Porco/análise , Animais , Fenômenos Químicos , Colágeno/química , Culinária , Hidrólise , Solubilidade , Suínos
17.
Biomed Pharmacother ; 139: 111659, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33962310

RESUMO

Chinese Traditional Medicines (CTMs) are very popular for therapeutic applications to cure several chronic diseases. Many researchers are trying to discover the potential application and actual mechanism of CTMs in order to scientifically prove their effects for commercial use. One of the main functions of CTMs is to aid stem cell regeneration. Since, this study was focused to fabricate CTMs incorporated fish collagen film, which has good biocompatibility in mammalian cell growth and thus investigated the effect on human Mesenchymal stem cells (hMSCs) proliferation and differentiation. In this study, three types of CTMs such as Genistein, Icariin, and Naringin were used for film fabrication. Mechanical properties of collagen films were improved by the addition of CTMs, especially in Collagen-Naringin films. Solubility and In-vitro biodegradation of collagen films were enhanced by the hydrophobicity and chemical interaction of CTMs with collagen. The proliferation rate was accelerated in hMSCs cultured on CTMs incorporated collagen films in a dose- and time-dependent manner. Proliferation biomarkers such as Ki-67 and BrdU levels were higher in hMSCs cultured on CTMs incorporated collagen films. The proliferative and differentiation effect of CTMs was further confirmed by higher gene expression of Collagen I, Runx2, c-Fos, SMAD3 and TGF-ß1 in hMSCs. Overall, this study provides a new insight on novel biomaterial fabrication using CTMs and fish collagen for making a compatible platform for in-vitro stem cell culture.


Assuntos
Materiais Biocompatíveis/química , Células da Medula Óssea , Colágeno/química , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Células-Tronco Mesenquimais , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Flavanonas/administração & dosagem , Flavanonas/química , Flavonoides/administração & dosagem , Flavonoides/química , Genisteína/administração & dosagem , Genisteína/química , Humanos , Urodelos
18.
Phys Chem Chem Phys ; 23(25): 13789-13796, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33942041

RESUMO

Water contributes to the structure of bone by coupling hydroxyapatite to collagen over the hierarchical levels of tissue organization. Bone water exists in two states, bound or mobile, each accomplishing different roles. Although many experimental studies show that the amount of bound water correlates with bone strength, a molecular understanding of the interactions between hydroxyapatite, collagen and water is missing. In this work, we unveil the water adsorption properties of bone tissues at the nanoscale using advanced density functional theory methods. We demonstrate that environmental factors such as collagen conformation or degree of confinement, rather than the surface itself, dictate the adsorption mode, strength and density of water on hydroxyapatite. While the results derived in this paper come from a simplified model of bone tissues, they are consistent with experimental observations and constitute a reasonable starting point for more realistic models of bone tissues. For example, we show that environmental changes expected in aging bone lead to reduced water adsorption capabilities, which is consistent with weaker bones at the macroscale. Our findings provide a new interpretation of molecular interactions in bone tissues with the potential to impact bone repair strategies.


Assuntos
Osso e Ossos/química , Colágeno/química , Durapatita/química , Água/química , Adsorção , Teoria da Densidade Funcional , Fenômenos Mecânicos , Modelos Químicos , Conformação Molecular , Solventes/química , Relação Estrutura-Atividade , Propriedades de Superfície
19.
Commun Biol ; 4(1): 608, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34021240

RESUMO

The long-term survival of biomaterial implants is often hampered by surgery-induced inflammation that can lead to graft failure. Considering that most corneas receiving grafts are either pathological or inflamed before implantation, the risk of rejection is heightened. Here, we show that bioengineered, fully synthetic, and robust corneal implants can be manufactured from a collagen analog (collagen-like peptide-polyethylene glycol hybrid, CLP-PEG) and inflammation-suppressing polymeric 2-methacryloyloxyethyl phosphorylcholine (MPC) when stabilized with the triazine-based crosslinker 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The resulting CLP-PEG-MPC implants led to reduced corneal swelling, haze, and neovascularization in comparison to CLP-PEG only implants when grafted into a mini-pig cornea alkali burn model of inflammation over 12 months. Implants incorporating MPC allowed for faster nerve regeneration and recovery of corneal sensation. CLP-PEG-MPC implants appear to be at a more advanced stage of regeneration than the CLP-PEG only implants, as evidenced by the presence of higher amounts of cornea-specific type V collagen, and a corresponding decrease in the presence of extracellular vesicles and exosomes in the corneal stroma, in keeping with the amounts present in healthy, unoperated corneas.


Assuntos
Álcalis/toxicidade , Queimaduras Químicas/complicações , Colágeno/farmacologia , Córnea/citologia , Hidrogéis/administração & dosagem , Inflamação/prevenção & controle , Fosforilcolina/química , Animais , Materiais Biocompatíveis/química , Queimaduras Químicas/patologia , Colágeno/química , Humanos , Hidrogéis/química , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Suínos , Porco Miniatura
20.
Phys Chem Chem Phys ; 23(22): 12692-12705, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34036961

RESUMO

The majority of in vitro studies of living cells are routinely conducted in a two-dimensional (2D) monolayer culture. Recent studies, however, suggest that 2D cell culture promotes specific types of aberrant cell behaviors due to the growth on non-physiologically stiff surfaces and the lack of the tissue-based extracellular matrix. Here, we investigate the sensitivity of the two-photon (2P) rotational dynamics of the intrinsic reduced nicotinamide adenine dinucleotide (phosphate), NAD(P)H, to changes in the metabolic state of the metastatic murine breast cancer cells (4T1) in 2D monolayer and three-dimensional (3D) collagen matrix cultures. Time-resolved 2P-associated anisotropy measurements reveal that the rotational dynamics of free and enzyme-bound NAD(P)H in 4T1 cells are correlated to changes in the metabolic state of 2D and 3D cell cultures. In addition to the type of cell culture, we also investigated the metabolic response of 4T1 cells to treatment with two metabolic inhibitors (MD1 and TPPBr). The statistical analyses of our results enabled us to identify which of the fitting parameters of the observed time-resolved associate anisotropy of cellular NAD(P)H were significantly sensitive to changes in the metabolic state of 4T1 cells. Using a black-box model, the population fractions of free and bound NAD(P)H were used to estimate the corresponding equilibrium constant and the standard Gibbs free energy changes that are associated with underlying metabolic pathways of 4T1 cells in 2D and 3D cultures. These rotational dynamics analyses are in agreement with the standard 2P-fluorescence lifetime imaging microscopy (FLIM) measurements on the same cell line, cell cultures, and metabolic inhibition. These studies represent an important step towards the development of a noninvasive, time-resolved associated anisotropy to complement 2P-FLIM in order to elucidate the underlying cellular metabolism and metabolic plasticity in more complex in vivo, tumor-like models using intrinsic NADH autofluorescence.


Assuntos
Neoplasias da Mama/metabolismo , Colágeno/metabolismo , NADP/metabolismo , Animais , Anisotropia , Neoplasias da Mama/patologia , Colágeno/química , Feminino , Camundongos , NADP/análise , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...