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1.
J Vis Exp ; (207)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767378

RESUMO

Ultrashort self-assembling peptides (SAPs) can spontaneously form nanofibers that resemble the extracellular matrix. These fibers allow the formation of hydrogels that are biocompatible, biodegradable, and non-immunogenic. We have previously proven that SAPs, when biofunctionalized with protein-derived motifs, can mimic the extracellular matrix characteristics that support colorectal organoid formation. These biofunctional peptide hydrogels retain the original parent peptide's mechanical properties, tunability, and printability while incorporating cues that allow cell-matrix interactions to increase cell adhesion. This paper presents the protocols needed to evaluate and characterize the effects of various biofunctional peptide hydrogels on cell adhesion and lumen formation using an adenocarcinoma cancer cell line able to form colorectal cancer organoids cost-effectively. These protocols will help evaluate biofunctional peptide hydrogel effects on cell adhesion and luminal formation using immunostaining and fluorescence image analysis. The cell line used in this study has been previously utilized for generating organoids in animal-derived matrices.


Assuntos
Neoplasias Colorretais , Hidrogéis , Organoides , Peptídeos , Organoides/citologia , Humanos , Neoplasias Colorretais/patologia , Linhagem Celular Tumoral , Hidrogéis/química , Peptídeos/química , Nanofibras/química , Adenocarcinoma/patologia , Matriz Extracelular/química , Adesão Celular/fisiologia
2.
Mar Pollut Bull ; 202: 116273, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569302

RESUMO

Coral reefs are home to a variety of species, and their preservation is a popular study area; however, monitoring them is a significant challenge, for which the use of robots offers a promising answer. The purpose of this study is to analyze the current techniques and tools employed in coral reef monitoring, with a focus on the role of robotics and its potential in transforming this sector. Using a systematic review methodology examining peer-reviewed literature across engineering and earth sciences from the Scopus database focusing on "robotics" and "coral reef" keywords, the article is divided into three sections: coral reef monitoring, robots in coral reef monitoring, and case studies. The initial findings indicated a variety of monitoring strategies, each with its own advantages and disadvantages. Case studies have also highlighted the global application of robotics in monitoring, emphasizing the challenges and opportunities unique to each context. Robotic interventions driven by artificial intelligence and machine learning have led to a new era in coral reef monitoring. Such developments not only improve monitoring but also support the conservation and restoration of these vulnerable ecosystems. Further research is required, particularly on robotic systems for monitoring coral nurseries and maximizing coral health in both indoor and open-sea settings.


Assuntos
Antozoários , Recifes de Corais , Monitoramento Ambiental , Robótica , Monitoramento Ambiental/métodos , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema
3.
Cancers (Basel) ; 16(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38398077

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is mostly diagnosed at advanced or even metastasized stages, limiting the prognoses of patients. Metastasis requires high tumor cell plasticity, implying phenotypic switching in response to changing environments. Here, epithelial-mesenchymal transition (EMT), being associated with an increase in cancer stem cell (CSC) properties, and its reversion are important. Since it is poorly understood whether different CSC phenotypes exist along the EMT axis and how these impact malignancy-associated properties, we aimed to characterize CSC populations of epithelial and mesenchymal-like PDAC cells. Single-cell cloning revealed CSC (Holoclone) and non-CSC (Paraclone) clones from the PDAC cell lines Panc1 and Panc89. The Panc1 Holoclone cells showed a mesenchymal-like phenotype, dominated by a high expression of the stemness marker Nestin, while the Panc89 Holoclone cells exhibited a SOX2-dominated epithelial phenotype. The Panc89 Holoclone cells showed enhanced cell growth and a self-renewal capacity but slow cluster-like invasion. Contrarily, the Panc1 Holoclone cells showed slower cell growth and self-renewal ability but were highly invasive. Moreover, cell variants differentially responded to chemotherapy. In vivo, the Panc1 and Panc89 cell variants significantly differed regarding the number and size of metastases, as well as organ manifestation, leading to different survival outcomes. Overall, these data support the existence of different CSC phenotypes along the EMT axis in PDAC, manifesting different metastatic propensities.

4.
ACS Bio Med Chem Au ; 4(1): 37-52, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38404747

RESUMO

The tragic COVID-19 pandemic, which has seen a total of 655 million cases worldwide and a death toll of over 6.6 million seems finally tailing off. Even so, new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to arise, the severity of which cannot be predicted in advance. This is concerning for the maintenance and stability of public health, since immune evasion and increased transmissibility may arise. Therefore, it is crucial to continue monitoring antibody responses to SARS-CoV-2 in the general population. As a complement to polymerase chain reaction tests, multiplex immunoassays are elegant tools that use individual protein or peptide antigens simultaneously to provide a high level of sensitivity and specificity. To further improve these aspects of SARS-CoV-2 antibody detection, as well as accuracy, we have developed an advanced serological peptide-based multiplex assay using antigen-fused peptide epitopes derived from both the spike and the nucleocapsid proteins. The significance of the epitopes selected for antibody detection has been verified by in silico molecular docking simulations between the peptide epitopes and reported SARS-CoV-2 antibodies. Peptides can be more easily and quickly modified and synthesized than full length proteins and can, therefore, be used in a more cost-effective manner. Three different fusion-epitope peptides (FEPs) were synthesized and tested by enzyme-linked immunosorbent assay (ELISA). A total of 145 blood serum samples were used, compromising 110 COVID-19 serum samples from COVID-19 patients and 35 negative control serum samples taken from COVID-19-free individuals before the outbreak. Interestingly, our data demonstrate that the sensitivity, specificity, and accuracy of the results for the FEP antigens are higher than for single peptide epitopes or mixtures of single peptide epitopes. Our FEP concept can be applied to different multiplex immunoassays testing not only for SARS-CoV-2 but also for various other pathogens. A significantly improved peptide-based serological assay may support the development of commercial point-of-care tests, such as lateral-flow-assays.

5.
ACS Nano ; 18(1): 164-177, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38133949

RESUMO

The rechargeable aqueous Zn ion battery (AZIB) is considered a promising candidate for future energy storage applications due to its intrinsic safety features and low cost. However, Zn dendrites and side reactions (e.g., corrosion, hydrogen evolution reaction, and inactive side product (Zn hydroxide sulfate) formation) at the Zn metal anode have been serious obstacles to realizing a satisfactory AZIB performance. The application of gel electrolytes is a common strategy for suppressing these problems, but the normally used highly cross-linked polymer matrix (e.g., polyacrylamide (PAM)) brings additional difficulties for battery assembly and recycling. Herein, we have developed a gel electrolyte for Zn metal anode stabilization, where a peptide matrix, a highly biocompatible material, is used for gel construction. Various experiments and simulations elucidate the sulfate anion-assisted self-assembly gel formation and its effect in stabilizing Zn metal anodes. Unlike polymer gel electrolytes, the peptide gel electrolyte can reversibly transform between gel and liquid states, thus facilitating the gel-involved battery assembly and recycling. Furthermore, the peptide gel electrolyte provides fast Zn ion diffusion (comparable to conventional liquid electrolyte) while suppressing side reactions and dendrite growth, thus achieving highly stable Zn metal anodes as validated in various cell configurations. We believe that our concept of gel electrolyte design will inspire more future directions for Zn metal anode protection based on gel electrolyte design.

6.
Langmuir ; 39(49): 17903-17920, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38039288

RESUMO

Coral reef survival is threatened globally. One way to restore this delicate ecosystem is to enhance coral growth by the controlled propagation of coral fragments. To be sustainable, this technique requires the use of biocompatible underwater adhesives. Hydrogels based on rationally designed ultrashort self-assembling peptides (USP) are of great interest for various biological and environmental applications, due to their biocompatibility and tunable mechanical properties. Implementing superior adhesion properties to the USP hydrogel compounds is crucial in both water and high ionic strength solutions and is relevant in medical and marine environmental applications such as coral regeneration. Some marine animals secrete large quantities of the aminoacids dopa and lysine to enhance their adhesion to wet surfaces. Therefore, the addition of catechol moieties to the USP sequence containing lysine (IIZK) should improve the adhesive properties of USP hydrogels. However, it is challenging to place the catechol moiety (Do) within the USP sequence at an optimal position without compromising the hydrogel self-assembly process and mechanical properties. Here, we demonstrate that, among three USP hydrogels, DoIIZK is the least adhesive and that the adhesiveness of the IIZDoK hydrogel is compromised by its poor mechanical properties. The best adhesion outcome was achieved using the IIZKDo hydrogel, the only one to show equally sound adhesive and mechanical properties. A mechanistic understanding of this outcome is presented here. This property was confirmed by the successful gluing of coral fragments by means of IIZKDo hydrogel that are still thriving after more than three years since the deployment. The validated biocompatibility of this underwater hydrogel glue suggests that it could be advantageously implemented for other applications, such as surgical interventions.


Assuntos
Antozoários , Recuperação e Remediação Ambiental , Hidrogéis , Animais , Adesivos/química , Di-Hidroxifenilalanina/química , Ecossistema , Hidrogéis/química , Lisina , Peptídeos
7.
Biomater Res ; 27(1): 111, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932837

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a hematological malignancy that remains a therapeutic challenge due to the high incidence of disease relapse. To better understand resistance mechanisms and identify novel therapies, robust preclinical models mimicking the bone marrow (BM) microenvironment are needed. This study aimed to achieve an automated fabrication process of a three-dimensional (3D) AML disease model that recapitulates the 3D spatial structure of the BM microenvironment and applies to drug screening and investigational studies. METHODS: To build this model, we investigated a unique class of tetramer peptides with an innate ability to self-assemble into stable hydrogel. An automated robotic bioprinting process was established to fabricate a 3D BM (niche-like) multicellular AML disease model comprised of leukemia cells and the BM's stromal and endothelial cellular fractions. In addition, monoculture and dual-culture models were also fabricated. Leukemia cell compatibility, functionalities (in vitro and in vivo), and drug assessment studies using our model were performed. In addition, RNAseq and gene expression analysis using TaqMan arrays were also performed on 3D cultured stromal cells and primary leukemia cells. RESULTS: The selected peptide hydrogel formed a highly porous network of nanofibers with mechanical properties similar to the BM extracellular matrix. The robotic bioprinter and the novel quadruple coaxial nozzle enabled the automated fabrication of a 3D BM niche-like AML disease model with controlled deposition of multiple cell types into the model. This model supported the viability and growth of primary leukemic, endothelial, and stromal cells and recapitulated cell-cell and cell-ECM interactions. In addition, AML cells in our model possessed quiescent characteristics with improved chemoresistance attributes, resembling more the native conditions as indicated by our in vivo results. Moreover, the whole transcriptome data demonstrated the effect of 3D culture on enhancing BM niche cell characteristics. We identified molecular pathways upregulated in AML cells in our 3D model that might contribute to AML drug resistance and disease relapse. CONCLUSIONS: Our results demonstrate the importance of developing 3D biomimicry models that closely recapitulate the in vivo conditions to gain deeper insights into drug resistance mechanisms and novel therapy development. These models can also improve personalized medicine by testing patient-specific treatments.

8.
Biomed Res Int ; 2023: 3892370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869628

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has greatly affected all aspect of life. Although several vaccines and pharmaceuticals have been developed against SARS-CoV-2, the emergence of mutated variants has raised several concerns. The angiotensin-converting enzyme (ACE2) receptor cell entry mechanism of this virus has not changed despite the vast mutation in emerging variants. Inhibiting the spike protein by which the virus identifies the host ACE2 receptor is a promising therapeutic countermeasure to keep pace with rapidly emerging variants. Here, we synthesized two ACE2-derived peptides, P1 and P25, to target and potentially inhibit SARS-CoV-2 cell entry. These peptides were evaluated in vitro using pseudoviruses that contained the SARS-CoV-2 original spike protein, the Delta-mutated spike protein, or the Omicron spike protein. An in silico investigation was also done for these peptides to evaluate the interaction of the synthesized peptides and the SARS-CoV-2 variants. The P25 peptide showed a promising inhibition potency against the tested pseudoviruses and an even higher inhibition against the Omicron variant. The IC50 of the Omicron variant was 60.8 µM, while the IC50s of the SARS-CoV-2 original strain and the Delta variant were 455.2 µM and 546.4 µM, respectively. The in silico experiments also showed that the amino acid composition design and structure of P25 boosted the interaction with the spike protein. These findings suggest that ACE2-derived peptides, such as P25, have the potential to inhibit SARS-CoV-2 cell entry in vitro. However, further in vivo studies are needed to confirm their therapeutic efficacy against emerging variants.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Humanos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Peptídeos/farmacologia , Ligação Proteica
9.
Diagnostics (Basel) ; 13(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37761360

RESUMO

PURPOSE: Next-generation sequencing (NGS) technology detects specific mutations that can provide treatment opportunities for colorectal cancer (CRC) patients. PATIENTS AND METHODS: We analyzed the mutation frequencies of common actionable genes and their association with clinicopathological characteristics and oncologic outcomes using targeted NGS in 107 Saudi Arabian patients without a family history of CRC. RESULTS: Approximately 98% of patients had genetic alterations. Frequent mutations were observed in BRCA2 (79%), CHEK1 (78%), ATM (76%), PMS2 (76%), ATR (74%), and MYCL (73%). The APC gene was not included in the panel. Statistical analysis using the Cox proportional hazards model revealed an unusual positive association between poorly differentiated tumors and survival rates (p = 0.025). Although no significant univariate associations between specific mutations or overall mutation rate and overall survival were found, our preliminary analysis of the molecular markers for CRC in a predominantly Arab population can provide insights into the molecular pathways that play a significant role in the underlying disease progression. CONCLUSIONS: These results may help optimize personalized therapy when drugs specific to a patient's mutation profile have already been developed.

10.
ACS Appl Mater Interfaces ; 15(40): 46710-46720, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37768145

RESUMO

Nature-inspired smart materials offer numerous advantages over environmental friendliness and efficiency. Emulating the excellent adhesive properties of mussels foot proteins, where the lysine is in close proximity with the 3,4-dihydroxy-l-phenylalanine (DOPA), we report the synthesis of a novel photocurable peptide-based adhesive consisting exclusively of these two amino acids. Our adhesive is a highly concentrated aqueous solution of a monomer, a cross-linker, and a photoinitiator. Lap-shear adhesion measurements on plastic and glass surfaces and comparison with different types of commercial adhesives showed that the adhesive strength of our glue is comparable when applied in air and superior when used underwater. No toxicity of our adhesive was observed when the cytocompatibility on human dermal fibroblast cells was assessed. Preliminary experiments with various tissues and coral fragments showed that our adhesive could be applied to wound healing and coral reef restoration. Given the convenience of the facile synthesis, biocompatibility, ease of application underwater, and high adhesive strength, we expect that our adhesive may find application, but not limited, to the biomedical and environmental field.

11.
ACS Nano ; 17(15): 14508-14531, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37477873

RESUMO

Cells' interactions with their microenvironment influence their morphological features and regulate crucial cellular functions including proliferation, differentiation, metabolism, and gene expression. Most biological data available are based on in vitro two-dimensional (2D) cellular models, which fail to recapitulate the three-dimensional (3D) in vivo systems. This can be attributed to the lack of cell-matrix interaction and the limitless access to nutrients and oxygen, in contrast to in vivo systems. Despite the emergence of a plethora of 3D matrices to address this challenge, there are few reports offering a proper characterization of these matrices or studying how the cell-matrix interaction influences cellular metabolism in correlation with gene expression. In this study, two tetrameric ultrashort self-assembling peptide sequences, FFIK and FIIK, were used to create in vitro 3D models using well-described human dermal fibroblast cells. The peptide sequences are derived from naturally occurring amino acids that are capable of self-assembling into stable hydrogels without UV or chemical cross-linking. Our results showed that 2D cultured fibroblasts exhibited distinct metabolic and transcriptomic profiles compared to 3D cultured cells. The observed changes in the metabolomic and transcriptomic profiles were closely interconnected and influenced several important metabolic pathways including the TCA cycle, glycolysis, MAPK signaling cascades, and hemostasis. Data provided here may lead to clearer insights into the influence of the surrounding microenvironment on human dermal fibroblast metabolic patterns and molecular mechanisms, underscoring the importance of utilizing efficient 3D in vitro models to study such complex mechanisms.


Assuntos
Sinais (Psicologia) , Transcriptoma , Humanos , Peptídeos/química , Células Cultivadas , Fibroblastos/metabolismo , Hidrogéis/química
12.
J Deaf Stud Deaf Educ ; 28(4): 373-386, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37522630

RESUMO

Among the existing sign language assessment tools, only a small number can be used in clinical settings. This contribution aims at presenting three comprehension assessment tests (two lexical and one syntactic) that offer a solid basis to build tools to assess language impairments in deaf signing adults. We provide the material and guidelines, based on psychometric analyses of the items, to make these tests suitable for clinical assessment. They are available for French Sign Language and Italian Sign Language. So far, the three tests were administered to three groups of deaf participants based on age of exposure (AoE) to sign language: native (AoE from birth), early (AoE = from 1 to 5 years), and late (AoE = from 6 to 15 years) signers. The results showed that the three tests are easy for the typical deaf signing population, and therefore, they can be adapted into tests that assess a deaf signing population with language impairments. Moreover, the results of the syntactic test reveal a categorial difference between native and non-native signers and therefore show the need for baselines that mirror the effect of AoE to sign language when assessing language competence, in particular in clinical assessment.


Assuntos
Compreensão , Idioma , Humanos , Adulto , Língua de Sinais , Psicometria
13.
Int J Bioprint ; 9(4): 719, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323500

RESUMO

62Articular cartilage is a nonvascularized and poorly cellularized tissue with a low self-repair capacity. Therefore, damage to this tissue due to trauma or degenerative joint diseases such as osteoarthritis needs a high-end medical intervention. However, such interventions are costly, have limited healing capacity, and could impair patients' quality of life. In this regard, tissue engineering and three-dimensional (3D) bioprinting hold great potential. However, identifying suitable bioinks that are biocompatible, with the desired mechanical stiffness, and can be used under physiological conditions is still a challenge. In this study, we developed two tetrameric self-assembling ultrashort peptide bioinks that are chemically well-defined and can spontaneously form nanofibrous hydrogels under physiological conditions. The printability of the two ultrashort peptides was demonstrated; different shape constructs were printed with high shape fidelity and stability. Furthermore, the developed ultrashort peptide bioinks gave rise to constructs with different mechanical properties that could be used to guide stem cell differentiation toward specific lineages. Both ultrashort peptide bioinks demonstrated high biocompatibility and supported the chondrogenic differentiation of human mesenchymal stem cells. Additionally, the gene expression analysis of differentiated stem cells with the ultrashort peptide bioinks revealed articular cartilage extracellular matrix formation preference. Based on the different mechanical stiffness of the two ultrashort peptide bioinks, they can be used to fabricate cartilage tissue with different cartilaginous zones, including the articular and calcified cartilage zones, which are essential for engineered tissue integration.

14.
Int J Bioprint ; 9(1): 633, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36866082

RESUMO

160Three-dimensional (3D) bioprinting systems, which are the prominent tools for biofabrication, should evolve around the cutting-edge technologies of tissue engineering. This is the case with organoid technology, which requires a plethora of new materials to evolve, including extracellular matrices with specific mechanical and biochemical properties. For a bioprinting system to facilitate organoid growth, it must be able to recreate an organ-like environment within the 3D construct. In this study, a well-established, self-assembling peptide system was employed to generate a laminin-like bioink to provide signals of cell adhesion and lumen formation in cancer stem cells. One bioink formulation led to the formation of lumen with outperforming characteristics, which showed good stability of the printed construct.

15.
Nat Commun ; 14(1): 1464, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928189

RESUMO

Antimicrobial peptides (AMPs) are promising next-generation antibiotics that can be used to combat drug-resistant pathogens. However, the high cost involved in AMP synthesis and their short plasma half-life render their clinical translation a challenge. To address these shortcomings, we report efficient production of bioactive amidated AMPs by transient expression of glycine-extended AMPs in Nicotiana benthamiana line expressing the mammalian enzyme peptidylglycine α-amidating mono-oxygenase (PAM). Cationic AMPs accumulate to substantial levels in PAM transgenic plants compare to nontransgenic N. benthamiana. Moreover, AMPs purified from plants exhibit robust killing activity against six highly virulent and antibiotic resistant ESKAPE pathogens, prevent their biofilm formation, analogous to their synthetic counterparts and synergize with antibiotics. We also perform a base case techno-economic analysis of our platform, demonstrating the potential economic advantages and scalability for industrial use. Taken together, our experimental data and techno-economic analysis demonstrate the potential use of plant chassis for large-scale production of clinical-grade AMPs.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Animais , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/biossíntese , Mamíferos , Plantas , Nicotiana/química , Nicotiana/genética , Farmacorresistência Bacteriana/efeitos dos fármacos
16.
Int J Mol Sci ; 24(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36982742

RESUMO

Methamphetamine, a highly addictive central nervous system (CNS) stimulant, is used worldwide as an anorexiant and attention enhancer. Methamphetamine use during pregnancy, even at therapeutic doses, may harm fetal development. Here, we examined whether exposure to methamphetamine affects the morphogenesis and diversity of ventral midbrain dopaminergic neurons (VMDNs). The effects of methamphetamine on morphogenesis, viability, the release of mediator chemicals (such as ATP), and the expression of genes involved in neurogenesis were evaluated using VMDNs isolated from the embryos of timed-mated mice on embryonic day 12.5. We demonstrated that methamphetamine (10 µM; equivalent to its therapeutic dose) did not affect the viability and morphogenesis of VMDNs, but it reduced the ATP release negligibly. It significantly downregulated Lmx1a, En1, Pitx3, Th, Chl1, Dat, and Drd1 but did not affect Nurr1 or Bdnf expression. Our results illustrate that methamphetamine could impair VMDN differentiation by altering the expression of important neurogenesis-related genes. Overall, this study suggests that methamphetamine use may impair VMDNs in the fetus if taken during pregnancy. Therefore, it is essential to exercise strict caution for its use in expectant mothers.


Assuntos
Estimulantes do Sistema Nervoso Central , Metanfetamina , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Camundongos , Animais , Neurônios Dopaminérgicos/metabolismo , Metanfetamina/toxicidade , Metanfetamina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Mesencéfalo/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Trifosfato de Adenosina/metabolismo , Diferenciação Celular
17.
Cell Death Dis ; 14(1): 3, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596765

RESUMO

The emergence of resistance to systemic therapies in pancreatic ductal adenocarcinoma (PDAC) is still a major obstacle in clinical practice. Both, constitutive and inducible NF-κB activity are known as key players in this context. To identify differentially expressed and TRAIL resistance mediating NF-κB target genes, TRAIL sensitive and resistant PDAC cell lines were analyzed by transcriptome assays. In this context, A20 was identified as an NF-κB/RelA inducible target gene. Translational PDAC tissue analysis confirmed the correlation of elevated A20 protein expression with activated RelA expression in PDAC patients. In in vitro experiments, an elevated A20 expression is accompanied by a specific resistance toward TRAIL-mediated apoptosis but not to chemotherapeutic-induced cell death. This TRAIL resistance was attributed to A20´s E3-ligase activity-mediating Zink finger domain. Furthermore, the ubiquitin-binding scaffold protein p62 was identified as indispensable for the TRAIL-mediated apoptosis-inducing pathway affected by A20. The results of this study identify A20 as a possible therapeutic target to affect resistance to TRAIL-induced apoptosis in PDAC cells.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , NF-kappa B/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Apoptose , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Fator de Transcrição RelA/genética , Neoplasias Pancreáticas
18.
FASEB Bioadv ; 4(10): 631-637, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36238363

RESUMO

Organotypic skin cultures represent in vitro models of skin which can be used for disease modeling, tissue engineering, and screening applications. Non-human collagen is currently the gold standard material used for the construction of the supporting matrix, however, its clinical applications are limited due to its xenogeneic origin. We have developed a novel peptide hydrogel-based skin construct that shows a pluristratified epidermis, basement membrane, and dermal compartment after 3 weeks of in vitro culture. Peptide-based constructs were compared to collagen-based constructs and stratification marker expression was histologically higher in peptide constructs than in collagen constructs. Transepithelial electrical resistance also showed mature barrier function in peptide constructs. This study presents a novel application of the self-assembling peptide hydrogel in a defined xeno-free in vitro system.

19.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36293205

RESUMO

The effects of second-generation antipsychotics on prenatal neurodevelopment, apoptotic neurodegeneration, and postnatal developmental delays have been poorly investigated. Even at standard doses, the use of quetiapine fumarate (QEPF) in pregnant women might be detrimental to fetal development. We used primary mouse embryonic neurons to evaluate the disruption of morphogenesis and differentiation of ventral midbrain (VM) neurons after exposure to QEPF. The dopaminergic VM neurons were deliberately targeted due to their roles in cognition, motor activity, and behavior. The results revealed that exposure to QEPF during early brain development decreased the effects of the dopaminergic lineage-related genes Tyrosine hydroxylase(Th), Dopamine receptor D1 (Drd1), Dopamine transporter (Dat), LIM homeobox transcription factor 1 alfa (Lmx1a), and Cell adhesion molecule L1 (Chl1), and the senescent dopaminergic gene Pituitary homeobox 3 (Pitx3). In contrast, Brain derived neurotrophic factor (Bdnf) and Nuclear receptor-related 1 (Nurr1) expressions were significantly upregulated. Interestingly, QEPF had variable effects on the development of non-dopaminergic neurons in VM. An optimal dose of QEPF (10 µM) was found to insignificantly affect the viability of neurons isolated from the VM. It also instigated a non-significant reduction in adenosine triphosphate formation in these neuronal populations. Exposure to QEPF during the early stages of brain development could also hinder the formation of VM and their structural phenotypes. These findings could aid therapeutic decision-making when prescribing 2nd generation antipsychotics in pregnant populations.


Assuntos
Molécula L1 de Adesão de Célula Nervosa , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Camundongos , Animais , Feminino , Humanos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Fumarato de Quetiapina/farmacologia , Fumarato de Quetiapina/metabolismo , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Mesencéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Fatores de Transcrição/metabolismo , Diferenciação Celular/genética , Trifosfato de Adenosina/metabolismo , Receptores Dopaminérgicos/metabolismo
20.
Int J Bioprint ; 8(3): 489, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105129

RESUMO

Three-dimensional (3D) bioprinting has emerged as a promising method for the engineering of tissues and organs. Still, it faces challenges in its widespread use due to issues with the development of bioink materials and the nutrient diffusion barrier inherent to these scaffold materials. Herein, we introduce a method to promote oxygen diffusion throughout the printed constructs using genetically encoded gas vesicles derived from haloarchaea. These hollow nanostructures are composed of a protein shell that allows gases to permeate freely while excluding the water flow. After printing cells with gas vesicles of various concentrations, the cells were observed to have increased activity and proliferation. These results suggest that air-filled gas vesicles can help overcome the diffusion barrier throughout the 3D bioprinted constructs by increasing oxygen availability to cells within the center of the construct. The biodegradable nature of the gas vesicle proteins combined with our promising results encourage their potential use as oxygen-promoting materials in biological samples.

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