Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 33.048
Filter
1.
Biomaterials ; 312: 122714, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39079462

ABSTRACT

Osteosarcoma, a malignant bone tumor often characterized by high hedgehog signaling activity, residual tumor cells, and substantial bone defects, poses significant challenges to both treatment response and postsurgical recovery. Here, we developed a nanocomposite hydrogel for the sustained co-delivery of bioactive magnesium ions, anti-PD-L1 antibody (αPD-L1), and hedgehog pathway antagonist vismodegib, to eradicate residual tumor cells while promoting bone regeneration post-surgery. In a mouse model of tibia osteosarcoma, this hydrogel-mediated combination therapy led to remarkable tumor growth inhibition and hence increased animal survival by enhancing the activity of tumor-suppressed CD8+ T cells. Meanwhile, the implanted hydrogel improved the microenvironment of osteogenesis through long-term sustained release of Mg2+, facilitating bone defect repair by upregulating the expression of osteogenic genes. After 21 days, the expression levels of ALP, COL1, RUNX2, and BGLAP in the Vis-αPD-L1-Gel group were approximately 4.1, 5.1, 5.5, and 3.4 times higher than those of the control, respectively. We believe that this hydrogel-based combination therapy offers a potentially valuable strategy for treating osteosarcoma and addressing the tumor-related complex bone diseases.


Subject(s)
Bone Neoplasms , Hydrogels , Immunotherapy , Nanocomposites , Osteosarcoma , Osteosarcoma/pathology , Osteosarcoma/drug therapy , Osteosarcoma/therapy , Animals , Hydrogels/chemistry , Nanocomposites/chemistry , Bone Neoplasms/drug therapy , Bone Neoplasms/pathology , Bone Neoplasms/therapy , Mice , Immunotherapy/methods , Cell Line, Tumor , Bone Regeneration/drug effects , Humans , Osteogenesis/drug effects , B7-H1 Antigen/metabolism , Mice, Inbred BALB C , Magnesium/chemistry
2.
Biomaterials ; 312: 122720, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39084098

ABSTRACT

Mesenchymal stem cells (MSCs) are expected to be useful therapeutics in osteoarthritis (OA), the most common joint disorder characterized by cartilage degradation. However, evidence is limited with regard to cartilage repair in clinical trials because of the uncontrolled differentiation and weak cartilage-targeting ability of MSCs after injection. To overcome these drawbacks, here we synthesized CuO@MSN nanoparticles (NPs) to deliver Sox9 plasmid DNA (favoring chondrogenesis) and recombinant protein Bmp7 (inhibiting hypertrophy). After taking up CuO@MSN/Sox9/Bmp7 (CSB NPs), the expressions of chondrogenic markers were enhanced while hypertrophic markers were decreased in response to these CSB-engineered MSCs. Moreover, a cartilage-targeted peptide (designated as peptide W) was conjugated onto the surface of MSCs via a click chemistry reaction, thereby prolonging the residence time of MSCs in both the knee joint cavity of mice and human-derived cartilage. In a surgery-induced OA mouse model, the NP and peptide dual-modified W-CSB-MSCs showed an enhancing therapeutic effect on cartilage repair in knee joints compared with other engineered MSCs after intra-articular injection. Most importantly, W-CSB-MSCs accelerated cartilage regeneration in damaged cartilage explants derived from OA patients. Thus, this new peptide and NPs dual engineering strategy shows potential for clinical applications to boost cartilage repair in OA using MSC therapy.


Subject(s)
Cell Differentiation , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Nanoparticles , Osteoarthritis , Peptides , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Animals , Osteoarthritis/therapy , Osteoarthritis/pathology , Nanoparticles/chemistry , Humans , Cell Differentiation/drug effects , Peptides/chemistry , Mesenchymal Stem Cell Transplantation/methods , Chondrogenesis/drug effects , Mice , SOX9 Transcription Factor/metabolism , SOX9 Transcription Factor/genetics , Cartilage, Articular/pathology , Cartilage, Articular/drug effects , Bone Morphogenetic Protein 7/chemistry , Bone Morphogenetic Protein 7/pharmacology , Tissue Engineering/methods , Regeneration/drug effects
3.
Biomaterials ; 312: 122724, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39106818

ABSTRACT

The residual bone tumor and defects which is caused by surgical therapy of bone tumor is a major and important problem in clinicals. And the sequential treatment for irradiating residual tumor and repairing bone defects has wildly prospects. In this study, we developed a general modification strategy by gallic acid (GA)-assisted coordination chemistry to prepare black calcium-based materials, which combines the sequential photothermal therapy of bone tumor and bone defects. The GA modification endows the materials remarkable photothermal properties. Under the near-infrared (NIR) irradiation with different power densities, the black GA-modified bone matrix (GBM) did not merely display an excellent performance in eliminating bone tumor with high temperature, but showed a facile effect of the mild-heat stimulation to accelerate bone regeneration. GBM can efficiently regulate the microenvironments of bone regeneration in a spatial-temporal manner, including inflammation/immune response, vascularization and osteogenic differentiation. Meanwhile, the integrin/PI3K/Akt signaling pathway of bone marrow mesenchymal stem cells (BMSCs) was revealed to be involved in the effect of osteogenesis induced by the mild-heat stimulation. The outcome of this study not only provides a serial of new multifunctional biomaterials, but also demonstrates a general strategy for designing novel blacked calcium-based biomaterials with great potential for clinical use.


Subject(s)
Bone Neoplasms , Bone Regeneration , Calcium , Gallic Acid , Mesenchymal Stem Cells , Gallic Acid/chemistry , Bone Regeneration/drug effects , Animals , Calcium/metabolism , Bone Neoplasms/therapy , Bone Neoplasms/drug therapy , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/cytology , Photothermal Therapy/methods , Osteogenesis/drug effects , Mice , Humans , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Cell Line, Tumor
4.
Methods Mol Biol ; 2848: 117-134, 2025.
Article in English | MEDLINE | ID: mdl-39240520

ABSTRACT

Retinal degenerative diseases including age-related macular degeneration and glaucoma are estimated to currently affect more than 14 million people in the United States, with an increased prevalence of retinal degenerations in aged individuals. An expanding aged population who are living longer forecasts an increased prevalence and economic burden of visual impairments. Improvements to visual health and treatment paradigms for progressive retinal degenerations slow vision loss. However, current treatments fail to remedy the root cause of visual impairments caused by retinal degenerations-loss of retinal neurons. Stimulation of retinal regeneration from endogenous cellular sources presents an exciting treatment avenue for replacement of lost retinal cells. In multiple species including zebrafish and Xenopus, Müller glial cells maintain a highly efficient regenerative ability to reconstitute lost cells throughout the organism's lifespan, highlighting potential therapeutic avenues for stimulation of retinal regeneration in humans. Here, we describe how the application of single-cell RNA-sequencing (scRNA-seq) has enhanced our understanding of Müller glial cell-derived retinal regeneration, including the characterization of gene regulatory networks that facilitate/inhibit regenerative responses. Additionally, we provide a validated experimental framework for cellular preparation of mouse retinal cells as input into scRNA-seq experiments, including insights into experimental design and analyses of resulting data.


Subject(s)
Ependymoglial Cells , Retina , Single-Cell Analysis , Animals , Mice , Single-Cell Analysis/methods , Retina/metabolism , Ependymoglial Cells/metabolism , Regeneration/genetics , Sequence Analysis, RNA/methods , Retinal Degeneration/genetics , Retinal Degeneration/therapy , RNA-Seq/methods , Disease Models, Animal
5.
Methods Mol Biol ; 2848: 75-84, 2025.
Article in English | MEDLINE | ID: mdl-39240517

ABSTRACT

Zebrafish maintain a remarkable ability to regenerate their neural retina following rapid and extensive loss of retinal neurons. This is mediated by Müller glial cells (MG), which re-enter the cell cycle to produce amplifying progenitor cells that eventually differentiate into the lost retinal neurons. For example, exposing adult albino zebrafish to intense light destroys large numbers of rod and cone photoreceptors, which are then restored by MG-mediated regeneration. Here, we describe an updated method for performing these acute phototoxic lesions to adult zebrafish retinas. Next, we contrast this method to a chronic, low light lesion model that results in a more muted and sustained damage to photoreceptors and does not trigger a MG-mediated regeneration response. Thus, these two methods can be used to compare and contrast the genetic and morphological changes associated with acute and chronic methods of photoreceptor degeneration.


Subject(s)
Disease Models, Animal , Retinal Degeneration , Zebrafish , Animals , Retinal Degeneration/pathology , Retinal Degeneration/genetics , Ependymoglial Cells/pathology , Ependymoglial Cells/metabolism , Light , Photoreceptor Cells, Vertebrate/pathology , Retina/pathology , Retina/metabolism
6.
Methods Mol Biol ; 2848: 135-150, 2025.
Article in English | MEDLINE | ID: mdl-39240521

ABSTRACT

Mammals do not possess the ability to spontaneously repair or regenerate damaged retinal tissue. In contrast to teleost fish which are capable of retina regeneration through the action of Müller glia, mammals undergo a process of reactive gliosis and scarring that inhibits replacement of lost neurons. Thus, it is important to discover novel methods for stimulating mammalian Müller glia to dedifferentiate and produce progenitor cells that can replace lost retinal neurons. Inducing an endogenous regenerative pathway mediated by Müller glia would provide an attractive alternative to stem cell injections or gene therapy approaches. Extracellular vesicles (EVs) are now recognized to serve as a novel form of cell-cell communication through the transfer of cargo from donor to recipient cells or by the activation of signaling cascades in recipient cells. EVs have been shown to promote proliferation and regeneration raising the possibility that delivery of EVs could be a viable treatment for visual disorders. Here, we provide protocols to isolate EVs for use in retina regeneration experiments.


Subject(s)
Extracellular Vesicles , Regeneration , Retina , Animals , Extracellular Vesicles/metabolism , Retina/metabolism , Retina/cytology , Retina/physiology , Ependymoglial Cells/metabolism , Ependymoglial Cells/cytology , Mice , Cell Communication , Cell Proliferation , Nerve Regeneration/physiology
7.
Methods Mol Biol ; 2848: 217-247, 2025.
Article in English | MEDLINE | ID: mdl-39240526

ABSTRACT

Various strategies for replacing retinal neurons lost in degenerative diseases are under investigation, including stimulating the endogenous regenerative capacity of Müller Glia (MG) as injury-inducible retinal stem cells. Inherently regenerative species, such as zebrafish, have provided key insights into mechanisms regulating MG dedifferentiation to a stem-like state and the proliferation of MG and MG-derived progenitor cells (MGPCs). Interestingly, promoting MG/MGPC proliferation is not sufficient for regeneration, yet mechanistic studies are often focused on this measure. To fully account for the regenerative process, and facilitate screens for factors regulating cell regeneration, an assay for quantifying cell replacement is required. Accordingly, we adapted an automated reporter-assisted phenotypic screening platform to quantify the pace of cellular regeneration kinetics following selective cell ablation in larval zebrafish. Here, we detail a method for using this approach to identify chemicals and genes that control the rate of retinal cell regeneration following selective retinal cell ablation.


Subject(s)
Zebrafish , Animals , Retina/cytology , Retina/metabolism , Phenotype , Cell Proliferation , Regeneration , Ependymoglial Cells/cytology , Ependymoglial Cells/metabolism , Stem Cells/cytology , Stem Cells/metabolism , Kinetics , Nerve Regeneration/physiology
8.
Methods Mol Biol ; 2848: 259-267, 2025.
Article in English | MEDLINE | ID: mdl-39240528

ABSTRACT

Controlled release or controlled drug delivery comprises the set of techniques and approaches to improve bioavailability through improved safety and/or efficacy using a carrier material for the molecule of interest. The predictability and tunability of these carriers make them ideal for protection, localization, and sustained presentation of a wide range of therapeutics, including growth factors implicated in cell survival and regeneration. Here we provide a method for encapsulating epidermal growth factor in a degradable polymer matrix for delivery to the cornea. Additional notes are included to demonstrate the wide-ranging capabilities of such methods for other materials, therapeutic agents, and sites of action within the eye.


Subject(s)
Cell Survival , Delayed-Action Preparations , Cell Survival/drug effects , Humans , Regeneration , Epidermal Growth Factor/metabolism , Animals , Cornea/metabolism , Cornea/cytology , Drug Delivery Systems/methods , Polymers/chemistry , Drug Carriers/chemistry
9.
Biomaterials ; 312: 122732, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39088913

ABSTRACT

Fully restoring the lost population of cardiomyocytes and heart function remains the greatest challenge in cardiac repair post myocardial infarction. In this study, a pioneered highly ROS-eliminating hydrogel was designed to enhance miR-19a/b induced cardiomyocyte proliferation by lowering the oxidative stress and continuously releasing miR-19a/b in infarcted myocardium in situ. In vivo lineage tracing revealed that ∼20.47 % of adult cardiomyocytes at the injected sites underwent cell division in MI mice. In MI pig the infarcted size was significantly reduced from 40 % to 18 %, and thereby marked improvement of cardiac function and increased muscle mass. Most importantly, our treatment solved the challenge of animal death--all the treated pigs managed to live until their hearts were harvested at day 50. Therefore, our strategy provides clinical conversion advantages and safety for healing damaged hearts and restoring heart function post MI, which will be a powerful tool to battle cardiovascular diseases in patients.


Subject(s)
Cell Proliferation , MicroRNAs , Myocardial Infarction , Myocytes, Cardiac , Oxidative Stress , Animals , MicroRNAs/metabolism , MicroRNAs/genetics , Myocytes, Cardiac/metabolism , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Oxidative Stress/drug effects , Mice , Swine , Hydrogels/chemistry , Mice, Inbred C57BL , Reactive Oxygen Species/metabolism
10.
Rev. biol. trop ; 72(1): e53238, ene.-dic. 2024. tab, graf
Article in English | SaludCR, LILACS | ID: biblio-1559323

ABSTRACT

Abstract Introduction: Evidence suggests that herbivores, such as peccaries, shape vegetation structure and diversity through predation, trampling, dispersal, and rooting behavior. Objective: To evaluate the impact of peccaries (Dycotiles tajacu) on the understory vegetation of the tropical rainforest in the Nogal-La Selva Local Biological Corridor, Costa Rica, comparing a site with the absence of peccaries to another with the presence of these animals. Methodology: From June to November 2021, 20 experimental exclusions and 20 free access plots, each measuring 2 m2 were used to quantify herbivory, the number of leaf blades, damaged leaves, healthy leaves, sapling height, and fallen biomass at both sites. Results: A higher sapling density was found in the Nogal Reserve, but a lower sapling diversity, while in La Selva there was a higher sapling diversity, but a lower density of seedlings. Herbivory and sapling height in La Selva exceeded those in Nogal. The exclusion of peccaries reduced seedling damage but did not affect the dynamics of fallen biomass. Conclusion: For the design, implementation, and evaluation of the effectiveness of biological corridors, it is crucial to consider plant-animal interactions to enhance the flow of ecological processes through functional and structural connectivity, analyzed from interactions such as those presented in this paper.


Resumen Introducción: Existe evidencia que herbívoros, como los saínos, dan forma a la estructura y diversidad de la vegetación a través del comportamiento de depredación, pisoteo, dispersión y enraizamiento. Objetivo: Evaluar el impacto de los saínos (Dycotiles tajacu) en la vegetación del sotobosque del bosque tropical húmedo en el Corredor Biológico Local Nogal-La Selva, Costa Rica, en un sitio con ausencia y en otro con presencia de saínos. Métodos: De junio a noviembre de 2021 se utilizaron 20 exclusiones experimentales y 20 parcelas de acceso libre de 2 m2, se cuantifico la herbivoría, número de láminas foliares, hojas dañadas, hojas sanas, altura de brinzales y biomasa caída en ambos sitios. Resultados: Se encontró una mayor densidad de brinzales en Reserva Nogal pero una menor diversidad, contrario en La Selva donde se encontró una mayor diversidad de brinzales, pero una menor densidad de plántulas. La herbivoría y la altura de brinzales en La Selva fue mayor que en Nogal. La exclusión de los saínos disminuyó el daño a las plántulas, pero no afectó la dinámica de la biomasa caída. Conclusión: Es necesario contemplar para el diseño, implementación y evaluación de la efectividad de corredores biológicos, las interacciones planta-animal, para potencializar el flujo de procesos ecológicos mediante la conectividad funcional y estructural, analizada a partir de interacciones como las presentadas en este trabajo.


Subject(s)
Animals , Artiodactyla , Forests , Animal Distribution , Tropical Ecosystem , Costa Rica
11.
J Environ Manage ; 369: 122297, 2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39217897

ABSTRACT

In recent years, heightened environmental concerns linked to agriculture have surged, with soil degradation standing out as a global issue. However, prevailing sustainability assessment methodologies in agriculture often overlook soil systems due to their intricate nature. This study aims to develop a methodology for evaluating soil degradation in agricultural practices using exergy regeneration costs. These costs determine the exergy required to restore soil fertility to pre-harvest levels. The methodology covers key soil factors like nutrients, organic matter, and prevalent issues like salinity, acidification, and erosion. For each of these factors, exergy regeneration costs are determined based on the energy needed to execute an optimal process for reverting the soil to its original or ideal state. The methodology has been applied to data from agricultural trials, showing that the calculated soil replacement cost is significantly higher compared to one of the most energy-demanding processes in agriculture, the use of urea. This demonstrates that agricultural soil degradation needs to be quantified for a correct evaluation of agricultural practices and their sustainability.

12.
Cell Mol Gastroenterol Hepatol ; : 101395, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39218152

ABSTRACT

The liver exhibits remarkable regenerative capacity. However, the limited ability of primary human hepatocytes to proliferate in vitro, combined with a compromised regenerative capacity induced by pathological conditions in vivo, presents significant obstacles to effective liver regeneration following liver injuries and diseases. Developing strategies to compensate for the loss of endogenous hepatocytes is crucial for overcoming these challenges, and this remains an active area of investigation. Lineage reprogramming, the process of directly converting one cell type into another bypassing the intermediate pluripotent state, has emerged as a promising method for generating specific cell types for therapeutic purposes in regenerative medicine. Here, we discuss the recent progress and emergent technologies in lineage reprogramming into hepatic cells, and their potential applications in enhancing liver regeneration or treating liver disease models. We also address controversies and challenges that confront this field.

13.
Carbohydr Polym ; 344: 122523, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39218546

ABSTRACT

Cellulose laminates represent a remarkable convergence of natural materials and modern engineering, offering a wide range of versatile applications in sustainable packaging, construction, and advanced materials. In this study, novel all-cellulose laminates are developed using an environmentally friendly approach, where freshly regenerated cellulose II films are stacked without the need for solvents (for impregnation and/or partial dissolution), chemical modifications, or resins. The structural and mechanical properties of these all-cellulose laminates were thoroughly investigated. This simple and scalable procedure results in transparent laminates with exceptional mechanical properties comparable to or even superior to common plastics, with E-modulus higher than 9 GPa for a single layer and 7 GPa for the laminates. These laminates are malleable and can be easily patterned. Depending on the number of layers, they can be thin and flexible (with just one layer) or thick and rigid (with three layers). Laminates were also doped with 10 wt% undissolved fibers without compromising their characteristics. These innovative all-cellulose laminates present a robust, eco-friendly alternative to traditional synthetic materials, thus bridging the gap between environmental responsibility and high-performance functionality.

14.
Anal Chim Acta ; 1324: 343089, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39218573

ABSTRACT

BACKGROUND: Optical fiber sensors have been used to detect glucose owing to advantages such as low cost, small size, and ease of operation etc. phenylboronic acid is one of the commonly used receptors for glucose detection, however phenylboronic acid based regenerative optical fiber sensors are commonly cumulative regeneration, renewable regeneration sensor has been missing from the literature. RESULTS: In this work, instead of using phenylboronic acid, we synthesized succinylaminobenzenoboronic acid molecule (BPOA) by introducing a short chain containing carboxyl group at the other end of phenylboronic acid then covalently bonded BPOA on the surface of excessively tilted fiber grating (Ex-TFG). This provides a very stable platform for renewable regeneration and the regenerative buffer was also optimized. The proposed renewable regeneration method exhibited higher linearity and sensitivity (R2 = 0.9992, 8 pm/mM) in relative to the conventional cumulative regeneration method (R2 = 0.9718, 4.9 pm/mM). The binding affinity between BPOA and glucose was found to be almost constant over 140 bind/release cycles with a variation of less than 0.3 % relative standard deviation. SIGNIFICANCE: The regenerative and label-free sensing capacity of the proposed device provides a theoretical foundation for label-free saccharide detection and the development of wearable glucose monitoring devices based on fiber optic sensors.


Subject(s)
Biosensing Techniques , Boronic Acids , Optical Fibers , Boronic Acids/chemistry , Glucose/analysis , Fiber Optic Technology , Limit of Detection
15.
Knee ; 51: 102-113, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39241670

ABSTRACT

BACKGROUND: Chondral defects of the knee can be identified in up to 60% of patients undergoing knee arthroscopy. The use of Autologous Matrix Induced Chondrogenesis (AMIC), which combines subchondral microfracture with a collagen membrane,has been increasingly used to treat these defects. AIMS: This review assesses the clinical, functional, and radiological outcomes of patients undergoing the AMIC procedure and reports any associated complications. METHODS: Studies with a minimum of 10 patients and fulfilled at least a 12-month follow up period with more than 70% follow up rate were included. Methodological quality was assessed using MINORS (Methodological Index for Non-Randomised Studies) criteria. The meta-analysis compared Lysholm, VAS (Visual Analog Scale), IKDC (International Knee Documentation Committee), KOOS (Knee Injury and Osteoarthritis Outcome Score) Pain, and Tegner clinical outcome measures at baseline and follow up. RESULTS: 18 studies (n = 490 patients) were included. The mean age was 35.2 [SD = 5.0] years and the mean defect size was 3.47 [SD = 0.96] cm2. There was a clinically significant improvement in Lysholm, IKDC, and KOOS scores of 30.36 [95% CI (25.80, 34.93)], 34.05 [95% CI (4.16, 43.95)], and 30.63 [95% CI (24.78, 36.47)] respectively; and reduction in VAS pain score of -4.10 [95%CI (-4.50, -3.71) at follow up. Improvement in Tegner score at follow up was not statistically significant: 0.21 [95% CI (-0.88, 1.30)],(p > 0.05). CONCLUSION: AMIC is a safe, effective, and reliable technique to treat knee chondral defects which can provide significant clinical, functional, and radiological improvements to patients.

16.
Stem Cell Reports ; 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39241770

ABSTRACT

Overexpression of cardiac reprogramming factors, including GATA4, HAND2, TBX5, and MEF2C (GHT/M), can directly reprogram cardiac fibroblasts (CFs) into induced cardiomyocytes (iCMs). Adeno-associated virus (AAV) vectors are widely used clinically, and vectors targeting cardiomyocytes (CMs) have been extensively studied. However, safe and efficient AAV vectors targeting CFs for in vivo cardiac reprogramming remain elusive. Therefore, we screened multiple AAV capsids and promoters to develop efficient and safe CF-targeting AAV vectors for in vivo cardiac reprogramming. AAV-DJ capsids containing periostin promoter (AAV-DJ-Postn) strongly and specifically expressed transgenes in resident CFs in mice after myocardial infarction (MI). Lineage tracing revealed that AAV-DJ-Postn vectors expressing GHT/M reprogrammed CFs into iCMs, which was further increased 2-fold using activated MEF2C via the fusion of the powerful MYOD transactivation domain (M-TAD) with GHT (AAV-DJ-Postn-GHT/M-TAD). AAV-DJ-Postn-GHT/M-TAD injection improved cardiac function and reduced fibrosis after MI. Overall, we developed new AAV vectors that target CFs for cardiac reprogramming.

17.
Int J Biol Macromol ; : 135343, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39241995

ABSTRACT

Rhodopsin is the key photoreceptor protein that mediates vision in low-light conditions. Mutations in rhodopsin are the cause of retinal degenerative diseases such as retinitis pigmentosa. Some of these mutations cause a decreased stability of the receptor. It is, therefore, of interest to find new approaches that can help improving rhodopsin conformational stability. In this study, we have analyzed the effect of retigabine, an anticonvulsant formerly used to treat epilepsy, on rhodopsin thermal stability, regeneration capacity, and signal transduction by means of UV-visible and fluorescence spectroscopic techniques. We find that retigabine enhances the thermal stability of dark-state rhodopsin and improves chromophore regeneration without disrupting the photobleaching process. Furthermore, retigabine does not significantly affect transducin activation. These results provide novel insights into the potential therapeutic applications of retigabine in the treatment of retinitis pigmentosa caused by rhodopsin mutations that cause a decreased stability of the mutated receptors.

18.
Results Probl Cell Differ ; 73: 249-297, 2024.
Article in English | MEDLINE | ID: mdl-39242383

ABSTRACT

The landscape of exosome research has undergone a significant paradigm shift, with a departure from early conceptions of exosomes as vehicles for cellular waste disposal towards their recognition as integral components of cellular communication with therapeutic potential. This chapter presents an exhaustive elucidation of exosome biology, detailing the processes of exosome biogenesis, release, and uptake, and their pivotal roles in signal transduction, tissue repair, regeneration, and intercellular communication. Additionally, the chapter highlights recent innovations and anticipates future directions in exosome research, emphasizing their applicability in clinical settings. Exosomes have the unique ability to navigate through tissue spaces to enter the circulatory system, positioning them as key players in tissue repair. Their contributory role in various processes of tissue repair, although in the nascent stages of investigation, stands out as a promising area of research. These vesicles function as a complex signaling network for intracellular and organ-level communication, critical in both pathological and physiological contexts. The chapter further explores the tissue-specific functionality of exosomes and underscores the advancements in methodologies for their isolation and purification, which have been instrumental in expanding the scope of exosome research. The differential cargo profiles of exosomes, dependent on their cellular origin, position them as prospective diagnostic biomarkers for tissue damage and regenerative processes. Looking ahead, the trajectory of exosome research is anticipated to bring transformative changes to biomedical fields. This includes advancing diagnostic and prognostic techniques that utilize exosomes as non-invasive biomarkers for a plethora of diseases, such as cancer, neurodegenerative, and cardiovascular conditions. Additionally, engineering exosomes through alterations of their native content or surface properties presents a novel frontier, including the synthesis of artificial or hybrid variants with enhanced functional properties. Concurrently, the ethical and regulatory frameworks surrounding exosome research, particularly in clinical translation, will require thorough deliberation. In conclusion, the diverse aspects of exosome research are coalescing to redefine the frontiers of diagnostic and therapeutic methodologies, cementing its importance as a discipline of considerable consequence in the biomedical sciences.


Subject(s)
Cell Communication , Exosomes , Exosomes/metabolism , Humans , Cell Communication/physiology , Animals , Wound Healing/physiology , Signal Transduction/physiology
19.
J Colloid Interface Sci ; 678(Pt A): 1121-1131, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39243478

ABSTRACT

Photoenzyme-coupled catalytic systems offer a promising avenue for selectively converting CO2 into high-value chemicals or fuels. However, two key challenges currently hinder their widespread application: the heavy reliance on the costly coenzyme NADH, and the necessity for metal-electron mediators or photosensitizers to address sluggish reaction kinetics. Herein, we present a robust 2D/2D MXene/C3N5 heterostructured artificial photosynthesis platform for in situ NADH regeneration and photoenzyme synergistic CO2 conversion to HCOOH. The efficiencies of utilizing and transmitting photogenerated charges are significantly enhanced by the abundant π-π conjugation electrons and well-engineered 2D/2D hetero-interfaces. Noteworthy is the achievement of nearly 100 % NADH regeneration efficiency within just 2.5 h by 5 % Ti3C2/C3N5 without electron mediators, and an impressive HCOOH production rate of 3.51 mmol g-1h-1 with nearly 100 % selectivity. This study represents a significant advancement in attaining the highest NADH yield without electron mediator and provides valuable insights into the development of superior 2D/2D heterojunctions for CO2 conversion.

20.
Natl J Maxillofac Surg ; 15(2): 214-219, 2024.
Article in English | MEDLINE | ID: mdl-39234119

ABSTRACT

Context: Human dental pulp stem cells (hDPSC) derived from dental pulp in conducive environment activated by chemicals can enhance chondrogenic cells for future animal model temporomandibular joint model. Aim: The study aims at evaluating the chemicals preconditioning (curcumin and rapamycin) efficacy toward chondrogenic proliferation of human dental pulp stem cells. Settings and Design: The in vitro study model with 10 premolar teeth extirpated pulp was processed under sterile chemical conditions. The cells viability was checked with calorimetric assay for adipogenic and chondrogenic, osteogenic lineages. The viability of the cells and the concentration of curcumin (CU) and rapamycin (RP) required for cell differentiation toward chondrogenic lineage were assessed. Material and Methods: The hDPSC was evaluated after explant long-term cultivation with characterization and chemical conditioning with dimethyl sulfoxide (DMSO) as control. MTT assay was used for cytotoxicity evaluation, cell viability, and proliferation. The dose optimization was observed with RP and CU. Chondrogenic proliferation was assessed with standard staining method of 0.1% Safranin O and 0.1% Alcian blue. Statistical Design: The flow cytometry analysis revealed good results for CD 90 compared to others. The intergroup analysis was done by ANOVA, and intragroup analysis was done by Post hoc Tukey's test. The intragroup analysis showed P value < 0.05 for RP in comparison between the various preconditioning agents CU and RP. The dosage of 10 µg/ml RP was considered statistically significant. Results: The flow cytometer analysis revealed good results for CD 90 compared to other surface markers. The dosage of 10 µg/ml RP was having good chondrogenic cell proliferation. The intragroup analysis showed P value < 0.05 for RP in comparison between the various preconditioning agents CU and RP. The calorimetric assay (MTT) quantitative analysis of the chondrogenic cells with Safranin O stain the standard deviation (SD = 0.017 for rapamycin), Alcian blue (SD = 0.49 for RP) in comparison to DMSO (control) and CU. Conclusion: RP activates mTOR pathway and hence stabilizes the stem cell maintenance of human dental pulp stem cell and the dose quantified can be used for future animal temporomandibular joint animal model.

SELECTION OF CITATIONS
SEARCH DETAIL