Degenerative mechanisms of retinal neurodegenerative diseases (RND) share common cellular and molecular signalization pathways. Curative treatment does not exist and cell-based therapy, through the ...paracrine properties of mesenchymal stem cells (MSC), is a potential unspecific treatment for RND. This study aimed to evaluate the neuroprotective capability of human bone marrow (bm) MSC secretome and its potential to modulate retinal responses to neurodegeneration.
An in vitro model of spontaneous retinal neurodegeneration was used to compare three days of monocultured neuroretina (NR), NR cocultured with bmMSC, and NR cultured with bmMSC secretome. We evaluated retinal morphology markers (Lectin peanut agglutinin, rhodopsin, protein kinase C α isoform, neuronal-specific nuclear protein, glial fibrillary acidic protein, TdT-mediated dUTP nick-end labeling, and vimentin) and proteins involved in apoptosis (apoptosis-inductor factor, caspase-3), necroptosis (MLKL), and autophagy (p62). Besides, we analyzed the relative mRNA expression through qPCR of genes involved in apoptosis (BAX, BCL2, CASP3, CASP8, CASP9), necroptosis (MLKL, RIPK1, RIPK3), autophagy (ATG7, BCLIN1, LC3B, mTOR, SQSTM1), oxidative stress (COX2, CYBA, CYBB, GPX6, SOD1, TXN2, TXNRD1) and inflammation (IL1, IL6, IL10, TGFb1, TNFa).
The bmMSC secretome preserves retinal morphology, limits pro-apoptotic- and pro-necroptotic-related gene and protein expression, modulates autophagy-related genes and proteins, and stimulates the activation of antioxidant-associated genes.
The neuroprotective ability of the bmMSC secretome is associated with activation of antioxidant machinery, modulation of autophagy, and inhibition of apoptosis and necroptosis during retinal degeneration. The neuroprotective effect of bmMSC secretomes in the presence/absence of MSC looks similar. Our current results reinforce the hypothesis that the human bmMSC secretome slows retinal neurodegeneration and may be a therapeutic option for treating RND.
The involvement of the extracellular matrix (ECM) in tumor progression has motivated the development of biomaterials mimicking the tumor ECM to develop more predictive cancer models. Particularly, ...polypeptides based on elastin could be an interesting approach to mimic the ECM due to their tunable properties. Here, we demonstrated that elastin-like recombinamer (ELR) hydrogels can be suitable biomaterials to develop breast cancer models. This hydrogel was formed by two ELR polypeptides, one containing sequences biodegradable by matrix metalloproteinase and cyclooctyne and the other carrying arginylglycylaspartic acid and azide groups to allow cell adhesion, biodegradability, and suitable stiffness through “click-chemistry” cross-linking. Our findings show that breast cancer or nontumorigenic breast cells showed high viability and cell proliferation for up to 7 days. MCF7 and MCF10A formed spheroids whereas MDA-MB-231 formed cell networks, with the expression of ECM and high drug resistance in all cases, evidencing that ELR hydrogels are a promising biomaterial for breast cancer modeling.
Controlling molecular interactions between bioinspired molecules can enable the development of new materials with higher complexity and innovative properties. Here we report on a dynamic system that ...emerges from the conformational modification of an elastin-like protein by peptide amphiphiles and with the capacity to access, and be maintained in, non-equilibrium for substantial periods of time. The system enables the formation of a robust membrane that displays controlled assembly and disassembly capabilities, adhesion and sealing to surfaces, self-healing and the capability to undergo morphogenesis into tubular structures with high spatiotemporal control. We use advanced microscopy along with turbidity and spectroscopic measurements to investigate the mechanism of assembly and its relation to the distinctive membrane architecture and the resulting dynamic properties. Using cell-culture experiments with endothelial and adipose-derived stem cells, we demonstrate the potential of this system to generate complex bioactive scaffolds for applications such as tissue engineering.
Retinal neurodegenerative diseases are the leading causes of visual impairment and irreversible blindness worldwide. Although the retinal response to injury remains closely similar between different ...retinal neurodegenerative diseases, available therapeutic alternatives are only palliative, too expensive, or very specific, such as gene therapy. In that sense, the development of broad-spectrum neuroprotective therapies seems to be an excellent option. In this regard, it is essential to identify molecular targets involved in retinal degeneration, such as cell death mechanisms. Apoptosis has been considered as the primary cell death mechanism during retinal degeneration; however, recent studies have demonstrated that the only use of anti-apoptotic drugs is not enough to confer good neuroprotection in terms of cell viability and preservation. For that reason, the interrelationship that exists between apoptosis and other cell death mechanisms needs to be characterized deeply to design future therapeutic options that simultaneously block the main cell death pathways. In that sense, the study aimed to characterize the programmed cell death (in terms of apoptosis and necroptosis) and autophagy response and modulation in retinal neurodegenerative diseases, using an
model of spontaneous retinal neurodegeneration. For that purpose, we measured the mRNA relative expression through qPCR of a selected pool of genes involved in apoptosis (
,
,
,
, and
), necroptosis (
,
, and
), and autophagy (
,
,
,
, and
); besides, the immunoexpression of their encoding proteins (Casp3, MLKL, RIPK1, LC3B, and p62) were analyzed using immunohistochemistry. Our results showed an increase of pro-apoptotic and pro-necroptotic related genes and proteins during
retinal neurodegeneration. Besides, we describe for the first time the modulation between programmed cell death mechanisms and autophagy in an
retinal neurodegeneration model. This study reinforces the idea that cell death mechanisms are closely interconnected and provides new information about molecular signaling and autophagy along the retinal degeneration process.
Materials that combine the functionalities of both of proteins and graphene are of great interest for the engineering of biosensing, drug delivery, and regenerative devices. Graphene oxide (GO) ...offers an opportunity to design GO‐protein interactions but the need for harsh reduction processes to enable GO photoexcitation remains a limitation. A disinfector‐assisted low temperature method to reduce GO‐protein materials and fabricate surgical dressings with tuneable photothermal efficiency and bioactive properties for the postoperative treatment of melanoma is reported. The approach harnesses the capacity of 70% ethanol to penetrate the protein shell of microorganisms to infiltrate GO‐protein complexes and reduce GO at low temperature (85 °C) while maintaining the material structure and bioactivity. Both experiments and coarse‐grained simulations are used to describe the reduction process and assess the material properties. In vitro and in vivo validation revealed the capacity of the dressings to prevent tumor recurrence and promote healing after tumor resection.
A method harnessing the capacity of 70% ethanol to penetrate the protein shell of microorganisms is reported to reduce GO‐protein complexes at low temperature (85 °C) and enable the fabrication of bioactive and conductive surgical dressings. The dressings are used for the postoperative treatment of melanoma and shown to prevent tumor recurrence and promote wound healing in a mice model.
In the development of tissue engineering strategies to replace, remodel, regenerate, or support damaged tissue, the development of bioinspired biomaterials that recapitulate the physicochemical ...characteristics of the extracellular matrix has received increased attention. Given the compositional heterogeneity and tissue‐to‐tissue variation of the extracellular matrix, the design, choice of polymer, crosslinking, and nature of the resulting biomaterials are normally depended on intended application. Generally, these biomaterials are usually made of degradable or nondegradable biomaterials that can be used as cell or drug carriers. In recent years, efforts to endow reciprocal biomaterial–cell interaction properties in scaffolds have inspired controlled synthesis, derivatization, and functionalization of the polymers used. In this regard, elastin‐like recombinant proteins have generated interest and continue to be developed further owing to their modular design at a molecular level. In this review, the authors provide a summary of key extracellular matrix features relevant to biomaterials design and discuss current approaches in the development of extracellular matrix‐inspired elastin‐like recombinant protein based biomaterials.
The extracellular matrix heterogeneity and associated cellular interactions have inspired the production of biomaterials with tailored reciprocal matrix–cell interactions. Hereof, elastin‐like recombinamers are gaining popularity owing to their modular design at a molecular level. Here, key extracellular matrix features relevant to biomaterials design are summarized and current approaches in the development of extracellular matrix‐inspired elastin‐like recombinamer based biomaterials are discussed.
The main clinical problems for dental implants are (1) formation of biofilm around the implant-a condition known as peri-implantitis and (2) inadequate bone formation around the implant-lack of ...osseointegration. Therefore, developing an implant to overcome these problems is of significant interest to the dental community. Chitosan has been reported to have good biocompatibility and anti-bacterial activity. An osseo-inductive recombinant elastin-like biopolymer (P-HAP), that contains a peptide derived from the protein statherin, has been reported to induce biomineralization and osteoblast differentiation. In this study, chitosan/P-HAP bi-layers were built on a titanium surface using a layer-by-layer (LbL) assembly technique. The difference in the water contact angle between consecutive layers, the representative peaks in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), X-ray photoelectron spectroscopy (XPS), and the changes in the topography between surfaces with a different number of bi-layers observed using atomic force microscopy (AFM), all indicated the successful establishment of chitosan/P-HAP LbL assembly on the titanium surface. The LbL-modified surfaces showed increased biomineralization, an appropriate mouse pre-osteoblastic cell response, and significant anti-bacterial activity against Streptococcus gordonii, a primary colonizer of tissues in the oral environment.
•We immobilized an elastin-like recombinamer, ELR, on CoCr, alloy through physisorption and covalent bonding.•The ELR combines a bioactive motif specific for endothelial cell adhesion.•The ELR ...immobilization is enhanced with silanization and surface charge.•The ELR coated surfaces displayed an improved HUVEC cell adhesion and spreading.
To improve cardiovascular implant success, metal-based stents are designated to modulate endothelial cells adhesion and migration in order to prevent restenosis and late thrombosis diseases. Biomimetic coatings with extra-cellular matrix adhesive biomolecules onto stents surfaces are a strategy to recover a healthy endothelium. However, the appropriate bioactive sequences to selective promote growth of endothelium and the biomolecules surface immobilization strategy remains to be elucidated. In this study, biofunctionalization of cobalt chromium, CoCr, alloy surfaces with elastin-like recombinamers, ELR, genetically modified with an REDV sequence, was performed to enhance metal surfaces endothelialization. Moreover, physical adsorption and covalent bonding were used as biomolecules binding strategies onto CoCr alloy. Surfaces were activated with plasma and etched with sodium hydroxide previous to silanization with 3-chloropropyltriethoxysilane and functionalized with the ELR. CoCr alloy surfaces were successfully biofunctionalized and the use of an ELR with an REDV sequence, allows conferring bioactivity to the biomaterials surface, demonstrating a higher cell adhesion and spreading of HUVEC cells on the different CoCr surfaces. This effect is emphasized as increases the amount of immobilized biomolecules and directly related to the immobilization technique, covalent bonding, and the increase of surface charge electronegativity. Our strategy of REDV elastin-like recombinamers immobilization onto CoCr alloy surfaces via covalent bonding through organosilanes provides a bioactive surface that promotes endothelial cell adhesion and spreading.
Elastin-like polypeptides in drug delivery Rodríguez-Cabello, José Carlos; Arias, Francisco Javier; Rodrigo, Matilde Alonso ...
Advanced drug delivery reviews,
02/2016, Volume:
97
Journal Article
Peer reviewed
Open access
The use of recombinant elastin-like materials, or elastin-like recombinamers (ELRs), in drug-delivery applications is reviewed in this work. Although ELRs were initially used in similar ways to ...other, more conventional kinds of polymeric carriers, their unique properties soon gave rise to systems of unparalleled functionality and efficiency, with the stimuli responsiveness of ELRs and their ability to self-assemble readily allowing the creation of advanced systems. However, their recombinant nature is likely the most important factor that has driven the current breakthrough properties of ELR-based delivery systems. Recombinant technology allows an unprecedented degree of complexity in macromolecular design and synthesis. In addition, recombinant materials easily incorporate any functional domain present in natural proteins. Therefore, ELR-based delivery systems can exhibit complex interactions with both their drug load and the tissues and cells towards which this load is directed. Selected examples, ranging from highly functional nanocarriers to macrodepots, will be presented.
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This Review discusses the use of elastin-like polymers and their recombinant version, elastin-like recombinamers, in drug-delivery systems. These macromolecules exhibit a number of interesting ...properties that are rarely found together in any other family of materials, especially extremely high biocompatibility, high bioactivity and functionality, complex yet fully controlled composition, and stimuli responsiveness. Appropriate design of these molecules opens up a broad range of different possibilities for their use in new therapeutic platforms. The first of these described herein is the use of ELRs in single-molecule devices as therapeutic entities in their own right. Subsequently, we describe how the self-assembly properties of these materials can be exploited to create nanocarriers and, eventually, microcarriers that are able to temporally and spatially control and direct the release of their drug load. Intracellular drug-delivery devices and nanocarriers for treating cancer are among the uses described in that section. Finally, the use of ELRs as base materials for implantable drug depots, in the form of hydrogels, is discussed.