Modulation of Mitochondrial Bioenergetics by Polydopamine Nanoparticles in Human iPSC-Derived Cardiomyocytes

SiRNA-mediated knockdown of TOP2B protects hiPSC-derived cardiomyocytes from doxorubicin-induced toxicity

AIMS

Doxorubicin (Dox) is a potent chemotherapeutic agent, but its use is limited by cardiotoxicity, primarily due to the disruption of Topoisomerase-2 beta (TOP2B) activity. Dexrazoxane (Dex), an FDA-approved cardioprotective drug, alleviates Dox-induced toxicity but lacks heart-specific targeting. This study investigates siRNA-mediated TOP2B knockdown as a more targeted strategy to protect cardiomyocytes from Dox-induced damage.

MATERIALS AND METHODS

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were treated with siRNA to knock down TOP2B and were then exposed to Dox. We compared the cardioprotective effects of siRNA-mediated knockdown to Dex treatment using cell viability, cell toxicity assay and electrophysiological evaluation was performed using a multielectrode array (MEA).

KEY FINDINGS

Our results demonstrate that TOP2B silencing significantly decreases apoptosis and improved cell viability, as compared to the Dex treatment. Additionally, electrophysiological assays using a Multielectrode Array (MEA) demonstrated enhanced contractility and conductivity in siRNA-treated hiPSC-CMs. Furthermore, transmission electron microscopy (TEM) data revealed that TOP2B knockdown preserves mitochondrial morphology and sarcomere structure, compared to Dox and Dex-treated groups.

SIGNIFICANCE

These findings suggest that siRNA-mediated TOP2B inhibition could provide a safer, more specific approach to mitigate Dox-induced cardiotoxicity.

Progress of nanomaterials in the treatment of ischemic heart disease

Medical or surgical interventions are commonly used to alleviate the clinical symptoms of individuals suffering from ischemic heart disease (IHD), but global morbidity and mortality remain high. This is due to the complexity of disease progression and the pathological basis of IHD, which primarily includes myocardial infarction (MI), myocardial ischemia-reperfusion injury (IRI), and heart failure (HF), as well as underlying mechanisms, such as mitochondrial damage, inflammation, oxidative stress, and cardiomyocyte death. However, many drugs have limitations, such as poor stability and low bioavailability, and surgical strategies are often ineffective in preventing disease recurrence. To overcome these problems, it is necessary to develop effective drug delivery systems and technologies. Due to their advantages in enhancing drug utilization, nanomaterials are being used to control drug biodistribution and achieve targeted accumulation, addressing the therapeutic needs of IHD. In this work, we first described the clinical aspects of MI, IRI, and HF in the context of IHD as well as their shared pathological origins. Next, clinical interventional procedures for IHD are summarized. Finally, recent developments in the use of nanomaterials for the treatment of MI, IRI, and HF are highlighted, along with potential directions for future research.

3D printing of GelMA/nanohydroxyapatite/melanin nanoparticles composite hydrogel scaffolds for bone regeneration through immunomodulation

Addressing bone tissue defects is a critical challenge in clinical practice, necessitating the development of biomaterials that can orchestrate both immune modulation and tissue regeneration. This study introduces and assesses the immunomodulatory effects and bone repair capabilities of a novel 3D-printed scaffold composed of gelatin methacryloyl (GelMA), nanohydroxyapatite, and melanin nanoparticles (GHM). The GHM scaffolds, characterized by their optimal porosity, viscosity, and mechanical strength, have been shown to effectively direct macrophage polarization from the initial M0 state to the anti-inflammatory M2 phenotype. Concurrently, osteogenic precursor cell lines MC3T3 are stimulated to differentiate into osteoblasts under the influence of macrophage-conditioned medium. In vivo studies using normal mice cranial defect models and macrophage-depleted cranial defect models have demonstrated that GHM scaffolds can attract macrophages to the implantation site, promote their M2 polarization, and consequently, significantly enhance bone formation and effectively treat cranial defects in mice. RNA-sequencing analysis has revealed elevated expression of the Leukemia inhibitory factor (Lif) gene in macrophages treated with GHM, implicating its role in regulating macrophage polarization. These findings underscore the potential of GHM scaffolds as an immunomodulatory biomaterial for bone tissue engineering applications.

Kill two birds with one stone: Biochar immobilised polydopamine coated compound bacterial agent for remediation of dibutyl phthalate contaminated soil

The severe contamination of the plasticizer dibutyl phthalate (DBP) in agriculture soils is often accompanied by a decrease in nutrient utilization. Though the combined application of a variety of microorganisms can simultaneously address the problems of soil contamination and nutrient deprivation, the activity and function of microorganisms can be severely inhibited by DBP, and studies on their protection under DBP contamination are almost non-existent. In this study, a compound bacterial agent KPSB was prepared by optimising with Fe3O4-modified biochar loaded with DBP-degrading bacterium Enterobacterium sp. DNB-S2 and polydopamine (PDA)-coated potassium-solubilizing bacterium Paenibacillus sp. KT. The results showed that KPSB was able to simultaneously remove DBP and increase the soil available potassium (K) content. PDA has good biocompatibility and shielding effect, and the strain KT coated by it has more complete cell membrane and stronger ability to secrete low molecular weight organic acids to promote K solubilization. The Fe3O4-modified biochar with suitable pore structure, large specific surface area and abundant functional groups could provide a good growth microenvironment for functional microorganisms and support the growth of strains while promoting the degradation of DBP. The expression of DBP-degradation-related genes was significantly increased in KPSB, which promoted the removal of DBP. In addition, KPSB has good acid and alkali resistance and a wide range of temperature adaptability, and is able to remove DBP and increase the available K content better under different environmental conditions. These results will provide new perspectives for the research of in situ soil remediation technology.

Miniaturized 3D-printed hand-operable dispersive sample pretreatment device with replaceable chitosan/polydopamine thin film metal sorbent for enhanced metal analysis

To address the increasing demand for sensitive and selective sample preparation methods for metal analysis; preconcentration of intended analyte from complex sample matrices before analysis is required to improve the performance of analysis instruments. In this study, we have engineered a sustainable and portable syringe-based hand-operable three-dimensionally (3D) printed sample pretreatment apparatus equipped with a replaceable bio-based thin- film metal sorbent. This device effectively addresses the challenges of sample matrix interference in metal analysis. A metal sorbent film composed of chitosan (CS) and polydopamine (PDA) leveraged the diverse functional groups in the CS/PDA matrix to significantly enhance the extraction efficiency for various metals. Our approach demonstrated excellent analytical performance, with coefficients of determination (R2) of 0.9982 for copper (Cu) and 0.996 for chromium (Cr). The method achieved low limits of detection (LOD) of 0.3 μg L-1 for Cr and 0.7 μg L-1 for Cu. Precision and practicality assessments using actual urine samples yielded satisfactory relative standard deviations (RSD%) ranging from of 1.6 %-8.5 % for both metals, indicating minimal interference from the sample matrix. Moreover, our approach exhibited robust performance even after seven consecutive extraction and desorption cycles, highlighting its sustainability and practical applicability for laboratory and on-site sample pretreatment.

Bioorthogonal non-canonical amino acid tagging to track transplanted human induced pluripotent stem cell-specific proteome

BACKGROUND

Human induced pluripotent stem cells (hiPSCs) and their differentiated cell types have a great potential for tissue repair and regeneration. While the primary focus of using hiPSCs has historically been to regenerate damaged tissue, emerging studies have shown a more potent effect of hiPSC-derived paracrine factors on tissue regeneration. However, the precise contents of the transplanted hiPSC-derived cell secretome are ambiguous. This is mainly due to the lack of tools to distinguish cell-specific secretome from host-derived proteins in a complex tissue microenvironment in vivo.

METHODS

In this study, we present the generation and characterization of a novel hiPSC line, L274G-hiPSC, expressing the murine mutant methionyl-tRNA synthetase, L274GMmMetRS, which can be used for tracking the cell specific proteome via biorthogonal non-canonical amino acid tagging (BONCAT). We assessed the trilineage differentiation potential of the L274G-hiPSCs in vitro and in vivo. Furthermore, we assessed the cell-specific proteome labelling in the L274G-hiPSC derived cardiomyocytes (L274G-hiPSC-CMs) in vitro following co-culture with wild type human umbilical vein derived endothelial cells and in vivo post transplantation in murine hearts.

RESULTS

We demonstrated that the L274G-hiPSCs exhibit typical hiPSC characteristics and that we can efficiently track the cell-specific proteome in their differentiated progenies belonging to the three germ lineages, including L274G-hiPSC-CMs. Finally, we demonstrated cell-specific BONCAT in transplanted L274G-hiPSC-CMs.

CONCLUSION

The novel L274G-hiPSC line can be used to study the cell-specific proteome of hiPSCs in vitro and in vivo, to delineate mechanisms underlying hiPSC-based cell therapies for a variety of regenerative medicine applications.

Advanced Nanomedicine Approaches for Myocardial Infarction Treatment

Myocardial infarction, usually caused by the rupture of atherosclerotic plaque, leads to irreversible ischemic cardiomyocyte death within hours followed by impaired cardiac performance or even heart failure. Current interventional reperfusion strategies for myocardial infarction still face high mortality with the development of heart failure. Nanomaterial-based therapy has made great progress in reducing infarct size and promoting cardiac repair after MI, although most studies are preclinical trials. This review focuses primarily on recent progress (2016-now) in the development of various nanomedicines in the treatment of myocardial infarction. We summarize these applications with the strategy of mechanism including anti-cardiomyocyte death strategy, activation of neovascularization, antioxidants strategy, immunomodulation, anti-cardiac remodeling, and cardiac repair.

Revitalizing Ancient Mitochondria with Nano-Strategies: Mitochondria-Remedying Nanodrugs Concentrate on Disease Control

Mitochondria, widely known as the energy factories of eukaryotic cells, have a myriad of vital functions across diverse cellular processes. Dysfunctions within mitochondria serve as catalysts for various diseases, prompting widespread cellular demise. Mounting research on remedying damaged mitochondria indicates that mitochondria constitute a valuable target for therapeutic intervention against diseases. But the less clinical practice and lower recovery rate imply the limitation of traditional drugs, which need a further breakthrough. Nanotechnology has approached favorable regiospecific biodistribution and high efficacy by capitalizing on excellent nanomaterials and targeting drug delivery. Mitochondria-remedying nanodrugs have achieved ideal therapeutic effects. This review elucidates the significance of mitochondria in various cells and organs, while also compiling mortality data for related diseases. Correspondingly, nanodrug-mediate therapeutic strategies and applicable mitochondria-remedying nanodrugs in disease are detailed, with a full understanding of the roles of mitochondria dysfunction and the advantages of nanodrugs. In addition, the future challenges and directions are widely discussed. In conclusion, this review provides comprehensive insights into the design and development of mitochondria-remedying nanodrugs, aiming to help scientists who desire to extend their research fields and engage in this interdisciplinary subject.

ROS scavenging activity of polydopamine nanoparticle-loaded supramolecular gelatin-based hydrogel promoted cardiomyocyte proliferation

Reactive oxygen species (ROS) play essential roles in cellular functions, but maintaining ROS balance is crucial for effective therapeutic interventions, especially during cell therapy. In this study, we synthesized an injectable gelatin-based hydrogel, in which polydopamine nanoparticles were entrapped using supramolecular interactions. The surfaces of the nanoparticles were modified using adamantane, enabling their interactions with β-cyclodextrin-conjugated with gelatin. We evaluated the cytotoxicity and antioxidant properties of the hydrogel on neonatal rat cardiomyocytes (NRCM), where it demonstrated the ability to increase the metabolic activity of NRCMs exposed to hydrogen peroxide (H2O2) after 5 days. Hydrogel-entrapped nanoparticle exhibited a high scavenging capability against hydroxyl radical, 1'-diphenyl-2-picrylhydrazyl radicals, and H2O2, surpassing the effectiveness of ascorbic acid solution. Notably, the presence of polydopamine nanoparticles within the hydrogel promoted the proliferation activity of NRCMs, even in the absence of excessive ROS due to H2O2 treatment. Additionally, when the hydrogel with nanoparticles was injected into an air pouch model, it reduced inflammation and infiltration of immune cells. Notably, the levels of anti-inflammatory factors, IL-10 and IL-4, were significantly increased, while the pro-inflammatory factor TNF-α was suppressed. Therefore, this novel ROS-scavenging hydrogel holds promise for both efficient cell delivery into inflamed tissue and promoting tissue repair.

Cell-nano interactions of polydopamine nanoparticles

Polydopamine (PDA) nanoparticles (NPs) have diverse nanomedicine applications owing to their biocompatibility and abundant entry to cells. Yet, our knowledge in their interactions with cells was infrequently studied until recent years. This review presents the latest insights into the cell-nano interactions of PDA NPs, including their 'self-targeting' to dopamine receptors for cellular entry without the aid of ligands, in vitro 'self-therapeutic' cellular responses (antiferroptosis, macrophage polarization, and modulation of mitochondrial bioenergetics) in the absence of drugs, and in vivo cellular localization and pharmacological properties upon various routes of administration. This review concludes with our perspectives on the therapeutic promise of PDA NPs and the need for studies on PDA biochemistry, biodegradability, and protein adsorption.

Nanotechnology in coronary heart disease

Coronary heart disease (CHD) is one of the major causes of death and disability worldwide, especially in low- and middle-income countries and among older populations. Conventional diagnostic and therapeutic approaches have limitations such as low sensitivity, high cost and side effects. Nanotechnology offers promising alternative strategies for the diagnosis and treatment of CHD by exploiting the unique properties of nanomaterials. In this review, we use bibliometric analysis to identify research hotspots in the application of nanotechnology in CHD and provide a comprehensive overview of the current state of the art. Nanomaterials with enhanced imaging and biosensing capabilities can improve the early detection of CHD through advanced contrast agents and high-resolution imaging techniques. Moreover, nanomaterials can facilitate targeted drug delivery, tissue engineering and modulation of inflammation and oxidative stress, thus addressing multiple aspects of CHD pathophysiology. We discuss the application of nanotechnology in CHD diagnosis (imaging and sensors) and treatment (regulation of macrophages, cardiac repair, anti-oxidative stress), and provide insights into future research directions and clinical translation. This review serves as a valuable resource for researchers and clinicians seeking to harness the potential of nanotechnology in the management of CHD. STATEMENT OF SIGNIFICANCE: Coronary heart disease (CHD) is the one of leading cause of death and disability worldwide. Nanotechnology offers new strategies for diagnosing and treating CHD by exploiting the unique properties of nanomaterials. This review uses bibliometric analysis to uncover research trends in the use of nanotechnology for CHD. We discuss the potential of nanomaterials for early CHD detection through advanced imaging and biosensing, targeted drug delivery, tissue engineering, and modulation of inflammation and oxidative stress. We also offer insights into future research directions and potential clinical applications. This work aims to guide researchers and clinicians in leveraging nanotechnology to improve CHD patient outcomes and quality of life.

Low-dose of polystyrene microplastics induce cardiotoxicity in mice and human-originated cardiac organoids

Microplastic particles (MP) are prevalent in both industrial production and the natural environment, posing a significant concern for human health. Daily diet, air inhalation, and skin contact are major routines of MP intake in human. The main injury target systems of MPs include the digestive system, respiratory system, and cardiovascular system. However, the study on MPs' adverse effects on the heart is less than other target organs. Previous in vivo studies have demonstrated that MPs can induce heart injuries, including abnormal heart rate, apoptosis of cardiomyocytes, mitochondrial membrane potential change, and fibrin overexpression. To address animal welfare concerns and overcome inter-species variations, this study employed a human pluripotent stem cell-derived in vitro three-dimensional cardiac organoid (CO) model to investigate the adverse effects of MPs on the human heart. The distinct cavities of COs allowed for the observation of MPs' aggregation and spatial distribution following polystyrene-MP (PS) exposure in a dynamic exposure system. After exposure to various concentrations of PS (0.025, 0.25 and 2.5 µg/mL, with the lowest concentration equivalent to human internal exposure levels), the COs exhibited increased oxidative stress, inflammatory response, apoptosis, and collagen accumulation. These findings were consistent with in vivo observations, in terms of increases in the interventricular septal thickness. The expression of hypertrophic-related genes of COs (MYH7B/ANP/BNP/COL1A1) changed noticeably and the cardiac-specific markers MYL2/MYL4/CX43 were also markedly elevated. Our findings revealed the PS could induced cardiac hypertrophy in vivo and in vitro, indicating that MP may be an under-recognized risk factor for cardiovascular system.

Functionalization of and through Melanin: Strategies and Bio-Applications

A unique feature of nanoparticles for bio-application is the ease of achieving multi-functionality through covalent and non-covalent functionalization. In this way, multiple therapeutic actions, including chemical, photothermal and photodynamic activity, can be combined with different bio-imaging modalities, such as magnetic resonance, photoacoustic, and fluorescence imaging, in a theragnostic approach. In this context, melanin-related nanomaterials possess unique features since they are intrinsically biocompatible and, due to their optical and electronic properties, are themselves very efficient photothermal agents, efficient antioxidants, and photoacoustic contrast agents. Moreover, these materials present a unique versatility of functionalization, which makes them ideal for the design of multifunctional platforms for nanomedicine integrating new functions such as drug delivery and controlled release, gene therapy, or contrast ability in magnetic resonance and fluorescence imaging. In this review, the most relevant and recent examples of melanin-based multi-functionalized nanosystems are discussed, highlighting the different methods of functionalization and, in particular, distinguishing pre-functionalization and post-functionalization. In the meantime, the properties of melanin coatings employable for the functionalization of a variety of material substrates are also briefly introduced, especially in order to explain the origin of the versatility of melanin functionalization. In the final part, the most relevant critical issues related to melanin functionalization that may arise during the design of multifunctional melanin-like nanoplatforms for nanomedicine and bio-application are listed and discussed.