Angiotensin II-Induced Hypertrophy in H9c2 Cells Reveals Severe Cytotoxicity of Graphene Oxide

This study investigates the differential cytotoxicity of reduced graphene oxide (RGO) and graphene oxide (GO) particles using an angiotensin II (Ang II)-induced hypertrophy model in H9c2 cells. Herein, GO particles were synthesized from graphite, and subsequent reduction was carried out to obtain RGO particles. To ensure a thorough assessment of particle size, functionalization, and purity, the particles were characterized by using UV-vis absorbance spectroscopy, dynamic light scattering, X-ray photoelectron spectroscopy, FTIR spectroscopy, Raman spectroscopy, and scanning electron microscopy. Comprehensive characterization revealed that the transformation from GO (∼21.6% content of oxygen) to RGO (∼13.3% content of oxygen) results in an enrichment in the proportion of sp2 carbon. Additionally, rat cardiac myoblasts of the H9c2 cell line were subjected to Ang II to induce cellular hypertrophy, leading to cytoskeleton remodeling, increased cardiac myocyte surface area, extracellular matrix alterations, and collagen type 1a upregulation. To evaluate cytotoxicity, H9c2 cells were treated with RGO and GO suspensions at concentrations ranging from 1 to 10,000 μg/mL, and metabolic viability was assessed in both concentration- and time-dependent assays. GO and RGO reduced the viability of H9c2 cells; however, the metabolic viability assays showed that the half-maximal inhibitory concentration (IC50) values for GO and RGO were significantly lower in hypertrophic cardiomyocytes, with GO exhibiting an IC50 of 12.6 ± 10.7 μg/mL and RGO exhibiting an IC50 of 86.3 ± 12.9 μg/mL, compared to control cells (676.0 ± 80.3 μg/mL for GO and 152.9 ± 40.1 μg/mL for RGO). These results demonstrate that under hypertrophic conditions, there is a significant increase of cytotoxicity for GO (50-fold increase) in comparison to RGO (1.7-fold increase). It was demonstrated that GO particles create a pro-oxidative environment that ultimately leads to mechanistic impairments and cell death. Vulnerable populations predisposed to cardiac damage may be at increased risk of experiencing toxicity caused by the use of GO particles in potential bioapplications.

Redefining the importance of polylactide-co-glycolide acid (PLGA) in drug delivery

The limitations of non-biodegradable polymers have paved the way for biodegradable polymers in the pharmaceutical and biomedical sciences over the years. Poly (lactic-co-glycolic acid) (PLGA), also known as 'Smart polymer', is one of the most successfully developed biodegradable polymers due to its favorable properties, such as biodegradability, biocompatibility, controllable drug release profile, and ability to alter surface with targeting agents for diagnosis and treatment. The release behavior of drugs from PLGA delivery devices is influenced by the physicochemical properties of PLGA. In this review, the current state of the art of PLGA, its synthesis, physicochemical properties, and degradation are discussed to enunciate the boundaries of future research in terms of its applicability with the optimized design in today's modern age. The fundamental objective of this review is to highlight the significance of PLGA as a polymer in the field of cancer, cardiovascular diseases, neurological disorders, dentistry, orthopedics, vaccine therapy, theranostics and lastly emerging epidemic diseases like COVID-19. Furthermore, the coverage of recent PLGA-based drug delivery systems including nanosystems, microsystems, scaffolds, hydrogels, etc. has been summarized. Overall, this review aims to disseminate the PLGA-driven revolution of the drug delivery arena in the pharmaceutical and biomedical industry and bridge the lacunae between material research, preclinical experimentation, and clinical reality.

Nanomedicine against Alzheimer's and Parkinson's Disease

Alzheimer's and Parkinson's are the two most rampant neurodegenerative disorders worldwide. Existing treatments have a limited effect on the pathophysiology but are unable to fully arrest the progression of the disease. This is due to the inability of these therapeutic molecules to efficiently cross the blood-brain barrier. We discuss how nanotechnology has enabled researchers to develop novel and efficient nano-therapeutics against these diseases. The development of nanotized drug delivery systems has permitted an efficient, site-targeted, and controlled release of drugs in the brain, thereby presenting a revolutionary therapeutic approach. Nanoparticles are also being thoroughly studied and exploited for their role in the efficient and precise diagnosis of neurodegenerative conditions. We summarize the role of different nano-carriers and RNAi-conjugated nanoparticle-based therapeutics for their efficacy in pre-clinical studies. We also discuss the challenges underlying the use of nanomedicine with a focus on their route of administration, concentration, metabolism, and any toxic effects for successful therapeutics in these diseases.

scFv-Anti-LDL(-)-Metal-Complex Multi-Wall Functionalized-Nanocapsules as a Promising Tool for the Prevention of Atherosclerosis Progression

Atherosclerosis can be originated from the accumulation of modified cholesterol-rich lipoproteins in the arterial wall. The electronegative LDL, LDL(-), plays an important role in the pathogenesis of atherosclerosis once this cholesterol-rich lipoprotein can be internalized by macrophages, contributing to the formation of foam cells, and provoking an immune-inflammatory response. Herein, we engineered a nanoformulation containing highly pure surface-functionalized nanocapsules using a single-chain fragment variable (scFv) reactive to LDL(-) as a ligand and assessed whether it can affect the LDL(-) uptake by primary macrophages and the progression of atherosclerotic lesions in Ldlr ^-/- mice. The engineered and optimized scFv-anti-LDL(-)-MCMN-Zn nanoformulation is internalized by human and murine macrophages in vitro by different endocytosis mechanisms. Moreover, macrophages exhibited lower LDL(-) uptake and reduced mRNA and protein levels of IL1B and MCP1 induced by LDL(-) when treated with this new nanoformulation. In a mouse model of atherosclerosis employing Ldlr ^-/- mice, intravenous administration of scFv-anti-LDL(-)-MCMN-Zn nanoformulation inhibited atherosclerosis progression without affecting vascular permeability or inducing leukocytes-endothelium interactions. Together, these findings suggest that a scFv-anti-LDL(-)-MCMN-Zn nanoformulation holds promise to be used in future preventive and therapeutic strategies for atherosclerosis.

Multiscale technologies for treatment of ischemic cardiomyopathy

The adult mammalian heart possesses only limited capacity for innate regeneration and the response to severe injury is dominated by the formation of scar tissue. Current therapy to replace damaged cardiac tissue is limited to cardiac transplantation and thus many patients suffer progressive decay in the heart's pumping capacity to the point of heart failure. Nanostructured systems have the potential to revolutionize both preventive and therapeutic approaches for treating cardiovascular disease. Here, we outline recent advancements in nanotechnology that could be exploited to overcome the major obstacles in the prevention of and therapy for heart disease. We also discuss emerging trends in nanotechnology affecting the cardiovascular field that may offer new hope for patients suffering massive heart attacks.

A nanoformulation containing a scFv reactive to electronegative LDL inhibits atherosclerosis in LDL receptor knockout mice

Atherosclerosis is a chronic inflammatory disease responsible for the majority of cases of myocardial infarction and ischemic stroke. The electronegative low-density lipoprotein, a modified subfraction of native LDL, is pro-inflammatory and plays an important role in atherogenesis. To investigate the effects of a nanoformulation (scFv anti-LDL(-)-MCMN-Zn) containing a scFv reactive to LDL(-) on the inhibition of atherosclerosis, its toxicity was evaluated in vitro and in vivo and further it was also administered weekly to LDL receptor knockout mice. The scFv anti-LDL(-)-MCMN-Zn nanoformulation did not induce cell death in RAW 264.7 macrophages and HUVECs. The 5mg/kg dose of scFv anti-LDL(-)-MCMN-Zn did not cause any typical signs of toxicity and it was chosen for the evaluation of its atheroprotective effect in Ldlr(-/-) mice. This nanoformulation significantly decreased the atherosclerotic lesion area at the aortic sinus, compared with that in untreated mice. In addition, the Il1b mRNA expression and CD14 protein expression were downregulated in the atherosclerotic lesions at the aortic arch of Ldlr(-/-) mice treated with scFv anti-LDL(-)-MCMN-Zn. Thus, the scFv anti-LDL(-)-MCMN-Zn nanoformulation inhibited the progression of atherosclerotic lesions, indicating its potential use in a future therapeutic strategy for atherosclerosis.

Serum albumin 'camouflage' of plant virus based nanoparticles prevents their antibody recognition and enhances pharmacokinetics

Plant virus-based nanoparticles (VNPs) are a novel class of nanocarriers with unique potential for biomedical applications. VNPs have many advantageous properties such as ease of manufacture and high degree of quality control. Their biocompatibility and biodegradability make them an attractive alternative to synthetic nanoparticles (NPs). Nevertheless, as with synthetic NPs, to be successful in drug delivery or imaging, the carriers need to overcome several biological barriers including innate immune recognition. Plasma opsonization can tag (V)NPs for clearance by the mononuclear phagocyte system (MPS), resulting in shortened circulation half lives and non-specific sequestration in non-targeted organs. PEG coatings have been traditionally used to 'shield' nanocarriers from immune surveillance. However, due to broad use of PEG in cosmetics and other industries, the prevalence of anti-PEG antibodies has been reported, which may limit the utility of PEGylation in nanomedicine. Alternative strategies are needed to tailor the in vivo properties of (plant virus-based) nanocarriers. We demonstrate the use of serum albumin (SA) as a viable alternative. SA conjugation to tobacco mosaic virus (TMV)-based nanocarriers results in a 'camouflage' effect more effective than PEG coatings. SA-'camouflaged' TMV particles exhibit decreased antibody recognition, as well as enhanced pharmacokinetics in a Balb/C mouse model. Therefore, SA-coatings may provide an alternative and improved coating technique to yield (plant virus-based) NPs with improved in vivo properties enhancing drug delivery and molecular imaging.

The Protein Corona of Plant Virus Nanoparticles Influences their Dispersion Properties, Cellular Interactions, and In Vivo Fates

Biomolecules in bodily fluids such as plasma can adsorb to the surface of nanoparticles and influence their biological properties. This phenomenon, known as the protein corona, is well established in the field of synthetic nanotechnology but has not been described in the context of plant virus nanoparticles (VNPs). The interaction between VNPs derived from Tobacco mosaic virus (TMV) and plasma proteins is investigated, and it is found that the VNP protein corona is significantly less abundant compared to the corona of synthetic particles. The formed corona is dominated by complement proteins and immunoglobulins, the binding of which can be reduced by PEGylating the VNP surface. The impact of the VNP protein corona on molecular recognition and cell targeting in the context of cancer and thrombosis is investigated. A library of functionalized TMV rods with polyethylene glycol (PEG) and peptide ligands targeting integrins or fibrin(ogen) show different dispersion properties, cellular interactions, and in vivo fates depending on the properties of the protein corona, influencing target specificity, and non-specific scavenging by macrophages. Our results provide insight into the in vivo properties of VNPs and suggest that the protein corona effect should be considered during the development of efficacious, targeted VNP formulations.

Laminin Receptor-Avid Nanotherapeutic EGCg-AuNPs as a Potential Alternative Therapeutic Approach to Prevent Restenosis

In our efforts to develop new approaches to treat and prevent human vascular diseases, we report herein our results on the proliferation and migration of human smooth muscles cells (SMCs) and endothelial cells (ECs) using epigallocatechin-3-gallate conjugated gold nanoparticles (EGCg-AuNPs) as possible alternatives to drug coated stents. Detailed in vitro stability studies of EGCg-AuNPs in various biological fluids, affinity and selectivity towards SMCs and ECs have been investigated. The EGCg-AuNPs showed selective inhibitory efficacy toward the migration of SMCs. However, the endothelial cells remained unaffected under similar experimental conditions. The cellular internalization studies have indicated that EGCg-AuNPs internalize into the SMCs and ECs within short periods of time through laminin receptor mediated endocytosis mode. Favorable toxicity profiles and selective affinity toward SMCs and ECs suggest that EGCg-AuNPs may provide attractive alternatives to drug coated stents and therefore offer new therapeutic approaches in treating cardiovascular diseases.

Nanotherapeutics for inhibition of atherogenesis and modulation of inflammation in atherosclerotic plaques

AIMS

Atherosclerotic development is exacerbated by two coupled pathophysiological phenomena in plaque-resident cells: modified lipid trafficking and inflammation. To address this therapeutic challenge, we designed and investigated the efficacy in vitro and ex vivo of a novel 'composite' nanotherapeutic formulation with dual activity, wherein the nanoparticle core comprises the antioxidant α-tocopherol and the shell is based on sugar-derived amphiphilic polymers that exhibit scavenger receptor binding and counteract atherogenesis.

METHODS AND RESULTS

Amphiphilic macromolecules were kinetically fabricated into serum-stable nanoparticles (NPs) using a core/shell configuration. The core of the NPs comprised either of a hydrophobe derived from mucic acid, M12, or the antioxidant α-tocopherol (α-T), while an amphiphile based on PEG-terminated M12 served as the shell. These composite NPs were then tested and validated for inhibition of oxidized lipid accumulation and inflammatory signalling in cultures of primary human macrophages, smooth muscle cells, and endothelial cells. Next, the NPs were evaluated for their athero-inflammatory effects in a novel ex vivo carotid plaque model and showed similar effects within human tissue. Incorporation of α-T into the hydrophobic core of the NPs caused a pronounced reduction in the inflammatory response, while maintaining high levels of anti-atherogenic efficacy.

CONCLUSIONS

Sugar-based amphiphilic macromolecules can be complexed with α-T to establish new anti-athero-inflammatory nanotherapeutics. These dual efficacy NPs effectively inhibited key features of atherosclerosis (modified lipid uptake and the formation of foam cells) while demonstrating reduction in inflammatory markers based on a disease-mimetic model of human atherosclerotic plaques.

Heteromultivalent ligand-decoration for actively targeted nanomedicine

Active targeting has become an important component of nanomedicine design where nanovehicles are surface-decorated with cell receptor-specific or disease matrix-specific ligands to enable site-selective binding, retention and delivery of theranostic cargo. In this context, there have been numerous reports regarding surface-modification of nanovehicles with antibodies, antibody fragments, carbohydrates, aptamers and peptides as targeting ligands. However, majority of these reports have focused on using a single type of targeting moiety on the vehicle surface. In any disease development and progression, multiple receptors and proteins are often spatio-temporally upregulated simultaneously and heterogeneously. Rationalizing from this, a significant advantage can be envisioned in targeting multiple entities simultaneously using vehicle co-decoration with multiple types of ligands, to enhance binding activity and targeting specificity. To this end, we present a comprehensive up-to-date review on research endeavors in heteromultivalent ligand-modification of nanovehicles and provide a mechanistic rationale as well as an insightful discussion of this promising area, including findings from our own research.

In silico design of anti-atherogenic biomaterials

Atherogenesis, the uncontrolled deposition of modified lipoproteins in inflamed arteries, serves as a focal trigger of cardiovascular disease (CVD). Polymeric biomaterials have been envisioned to counteract atherogenesis based on their ability to repress scavenger mediated uptake of oxidized lipoprotein (oxLDL) in macrophages. Following the conceptualization in our laboratories of a new library of amphiphilic macromolecules (AMs), assembled from sugar backbones, aliphatic chains and poly(ethylene glycol) tails, a more rational approach is necessary to parse the diverse features such as charge, hydrophobicity, sugar composition and stereochemistry. In this study, we advance a computational biomaterials design approach to screen and elucidate anti-atherogenic biomaterials with high efficacy. AMs were quantified in terms of not only 1D (molecular formula) and 2D (molecular connectivity) descriptors, but also new 3D (molecular geometry) descriptors of AMs modeled by coarse-grained molecular dynamics (MD) followed by all-atom MD simulations. Quantitative structure-activity relationship (QSAR) models for anti-atherogenic activity were then constructed by screening a total of 1164 descriptors against the corresponding, experimentally measured potency of AM inhibition of oxLDL uptake in human monocyte-derived macrophages. Five key descriptors were identified to provide a strong linear correlation between the predicted and observed anti-atherogenic activity values, and were then used to correctly forecast the efficacy of three newly designed AMs. Thus, a new ligand-based drug design framework was successfully adapted to computationally screen and design biomaterials with cardiovascular therapeutic properties.

Nanomedicine: a primer for surgeons

The advances in science have resulted in the emergence of nanotechnology, which deals with the design and use of tools and devices of size 1-100 nm. The application of nanotechnologies to medicine is thus termed nanomedicine. Significant research has been focused on this new and exciting field and this review article will describe the basics of nanomedicine. This is followed by its experimental and clinical applications in diagnostics, drug therapy and regenerative medicine. Safety issues of in vivo use of nanomaterials are also discussed. In the future, it is foreseen that nanomedicine will facilitate the development of personalized medicine and will have a major impact on the delivery of better healthcare.

Magnetic Drug Targeting as New Therapeutic Option for the Treatment of Biomaterial Infections

Implant-associated infections are a challenging problem in surgery. Bacteria in biofilms are difficult to treat as they are less susceptible to antibiotics or antiseptics which require high drug concentrations at the site of infection. We present a novel strategy to concentrate high antibiotic doses systemically at the target site using newly developed antibiotic-functionalized nanoparticles directed by a magnetic drug-targeting system. The important and effective antibiotic gentamicin served as antimicrobial substance and was ionically or covalently attached to magnetic nanoparticles. Subsequently, the particles were characterized thoroughly. Anti-infective properties with regard to Staphylococcus aureus and the degree of cytotoxicity concerning human umbilical vein endothelial cells were determined. The enrichment of the magnetic nanoparticles at the surface of model tubes in circulatory experiments was investigated. We describe a promising technique for the loading of magnetic nanoparticles to treat systemic infections. Gentamicin-coated magnetic nanoparticles reduced bacterial growth even beyond pathologically relevant concentrations within 24 h. Excellent concentration independent biocompatibility was found for the nanoparticles themselves and we demonstrate that the magnetic nanoparticles can be navigated and concentrated on surfaces of model implants using a permanent magnetic field.

Nanotechnology: emerging tool for diagnostics and therapeutics

Nanotechnology is an emerging technology which is an amalgamation of different aspects of science and technology that includes disciplines such as electrical engineering, mechanical engineering, biology, physics, chemistry, and material science. It has potential in the fields of information and communication technology, biotechnology, and medicinal technology. It involves manipulating the dimensions of nanoparticles at an atomic scale to make use of its physical and chemical properties. All these properties are responsible for the wide application of nanoparticles in the field of human health care. Promising new technologies based on nanotechnology are being utilized to improve diverse aspects of medical treatments like diagnostics, imaging, and gene and drug delivery. This review summarizes the most promising nanomaterials and their application in human health.

Polymer-based therapeutics: nanoassemblies and nanoparticles for management of atherosclerosis

Coronary arterial disease, one of the leading causes of adult mortality, is triggered by atherosclerosis. A disease with complex etiology, atherosclerosis results from the progressive long-term combination of atherogenesis, the accumulation of modified lipoproteins within blood vessel walls, along with vascular and systemic inflammatory processes. The management of atherosclerosis is challenged by the localized flare-up of several multipronged signaling interactions between activated monocytes, atherogenic macrophages and inflamed or dysfunctional endothelial cells. A new generation of approaches is now emerging founded on multifocal, targeted therapies that seek to reverse or ameliorate the atheroinflammatory cascade within the vascular intima. This article reviews the various classes and primary examples of bioactive configurations of nanoscale assemblies. Of specific interest are polymer-based or polymer-lipid micellar assemblies designed as multimodal receptor-targeted blockers or drug carriers whose activity can be tuned by variations in polymer hydrophobicity, charge, and architecture. Also reviewed are emerging reports on multifunctional nanoassemblies and nanoparticles for improved circulation and enhanced targeting to atheroinflammatory lesions and atherosclerotic plaques.

Nanotechnology Applications in Vascular Disease

The confluence of nanotechnology and medicine: Nanomedicine is poised to revolutionize the delivery of health care to individuals and populations in the 21st century. Every medical specialty stands to be impacted as emerging nanotechnologies propel modalities for prevention, screening, diagnosis, and treatment. Medical interventions targeting vascular disease are becoming increasingly important, given current epidemiologic trends in morbidity and mortality due to these diseases. Vascular disease is a term that encompasses a collection of pathologies that affect the vessels (arteries, veins, and lymphatics) or vasculature in the body. The purpose of this article is to highlight current and emerging nanotechnologies aimed at vascular disease. Select, clinically relevant examples are described in the categories of drugs and drug delivery, imaging, sensors, biomaterials, diagnostics, and novel therapeutics. Several promising nanomedicine applications that target vascular disease are currently under various stages of development from bench top research to clinical trials. Given the rate of investment, promising research results and progression of many products to market nanomedicine applications in the prevention, diagnosis, and treatment of vascular disease holds great promise for improving the stand of care.

Current advances in research and clinical applications of PLGA-based nanotechnology

Co-polymer poly(lactic-co-glycolic acid) (PLGA) nanotechnology has been developed for many years and has been approved by the US FDA for the use of drug delivery, diagnostics and other applications of clinical and basic science research, including cardiovascular disease, cancer, vaccine and tissue engineering. This article presents the more recent successes of applying PLGA-based nanotechnologies and tools in these medicine-related applications. It focuses on the possible mechanisms, diagnosis and treatment effects of PLGA preparations and devices. This updated information will benefit to both new and established research scientists and clinical physicians who are interested in the development and application of PLGA nanotechnology as new therapeutic and diagnostic strategies for many diseases.