FM19G11-Loaded Gold Nanoparticles Enhance the Proliferation and Self-Renewal of Ependymal Stem Progenitor Cells Derived from ALS Mice

A review: oligodendrocytes in neuronal axonal conduction and methods for enhancing their performance

OBJECTIVES

This review explores the vital role of oligodendrocytes in axon myelination and efficient neuronal transmission and the impact of dysfunction resulting from neurotransmitter deficiencies related disorders. Furthermore, the review also provides insight into the potential of bionanotechnology for addressing neurodegenerative diseases by targeting oligodendrocytes.

METHODS

A review of literature in the field was conducted using Google scholar. Systematic searches were performed to identify relevant studies and reviews addressing the role of oligodendrocytes in neural function, the influence of neurotransmitters on oligodendrocyte differentiation, and the potential of nanotechnology-based strategies for targeted therapy of oligodendrocytes.

RESULTS

This review indicates the mechanisms underlying oligodendrocyte differentiation and the influence of neurotransmitters on this process. The importance of action potentials and neurotransmission in neural function and the susceptibility of damaged nerve axons to ischemic or toxic damage is provided in detail. The potential of bionanotechnology for targeting neurodegenerative diseases using nanotechnology-based strategies, including polymeric, lipid-based, inorganic, organic, and biomimetic nanoparticles, suggests better management of neurodegenerative disorders.

CONCLUSION

While nanotechnology-based biomaterials show promise for targeted oligodendrocyte therapy in addressing neurodegenerative disorders linked to oligodendrocyte dysfunction, encapsulating neuroprotective agents within nanoparticles offers additional advantages. Nano-based delivery systems effectively protect drugs from degradation and prolong their therapeutic effects, holding promise in overcoming the blood-brain barrier by facilitating drug transport. However, a multifaceted approach is essential to enhance oligodendrocyte differentiation, promote myelin repair, and facilitate myelin dynamics with reduced toxicity. Further research is needed to elucidate the optimal therapeutic approaches and enhance patient outcomes.

The role of glial cells in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) has traditionally been considered a neuron-centric disease. This view is now outdated, with increasing recognition of cell autonomous and non-cell autonomous contributions of central and peripheral nervous system glia to ALS pathomechanisms. With glial research rapidly accelerating, we comprehensively interrogate the roles of astrocytes, microglia, oligodendrocytes, ependymal cells, Schwann cells and satellite glia in nervous system physiology and ALS-associated pathology. Moreover, we highlight the inter-glial, glial-neuronal and inter-system polylogue which constitutes the healthy nervous system and destabilises in disease. We also propose classification based on function for complex glial reactive phenotypes and discuss the pre-requisite for integrative modelling to advance translation. Given the paucity of life-enhancing therapies currently available for ALS patients, we discuss the promising potential of harnessing glia in driving ALS therapeutic discovery.

Multifunctional Nanocarriers for Alzheimer's Disease: Befriending the Barriers

Neurodegenerative diseases (NDDs) have been increasing in incidence in recent years and are now widespread worldwide. Neuronal death is defined as the progressive loss of neuronal structure or function which is closely associated with NDDs and represents the intrinsic features of such disorders. Amyotrophic lateral sclerosis, frontotemporal dementia, Alzheimer's, Parkinson's, and Huntington's diseases (AD, PD, and HD, respectively) are considered neurodegenerative diseases that affect a large number of people worldwide. Despite the testing of various drugs, there is currently no available therapy that can remedy or effectively slow the progression of these diseases. Nanomedicine has the potential to revolutionize drug delivery for the management of NDDs. The use of nanoparticles (NPs) has recently been developed to improve drug delivery efficiency and is currently subjected to extensive studies. Nanoengineered particles, known as nanodrugs, can cross the blood-brain barrier while also being less invasive compared to the most treatment strategies in use. Polymeric, magnetic, carbonic, and inorganic NPs are examples of NPs that have been developed to improve drug delivery efficiency. Primary research studies using NPs to cure AD are promising, but thorough research is needed to introduce these approaches to clinical use. In the present review, we discussed the role of metal-based NPs, polymeric nanogels, nanocarrier systems such as liposomes, solid lipid NPs, polymeric NPs, exosomes, quantum dots, dendrimers, polymersomes, carbon nanotubes, and nanofibers and surfactant-based systems for the therapy of neurodegenerative diseases. In addition, we highlighted nanoformulations such as N-butyl cyanoacrylate, poly(butyl cyanoacrylate), D-penicillamine, citrate-coated peptide, magnetic iron oxide, chitosan (CS), lipoprotein, ceria, silica, metallic nanoparticles, cholinesterase inhibitors, an acetylcholinesterase inhibitors, metal chelators, anti-amyloid, protein, and peptide-loaded NPs for the treatment of AD.

FM19G11-loaded nanoparticles modulate energetic status and production of reactive oxygen species in myoblasts from ALS mice

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motor neurons. Considerable evidence indicates that early skeletal muscle atrophy plays a crucial role in the disease pathogenesis, leading to an altered muscle-motor neuron crosstalk that, in turn, may contribute to motor neuron degeneration. Currently, there is no effective treatment for ALS, highlighting the need to dig deeper into the pathological mechanisms for developing innovative therapeutic strategies. FM19G11 is a novel drug able to modulate the global cellular metabolism, but its effects on ALS skeletal muscle atrophy and mitochondrial metabolism have never been evaluated, yet. This study investigated whether FM19G11-loaded nanoparticles (NPs) may affect the bioenergetic status in myoblasts isolated from G93A-SOD1 mice at different disease stages. We found that FM19G1-loaded NP treatment was able to increase transcriptional levels of Akt1, Akt3, Mef2a, Mef2c and Ucp2, which are key genes associated with cell proliferation (Akt1, Akt3), muscle differentiation (Mef2c), and mitochondrial activity (Ucp2), in G93A-SOD1 myoblasts. These cells also showed a significant reduction of mitochondrial area and networks, in addition to decreased ROS production after treatment with FM19G11-loaded NPs, suggesting a ROS clearance upon the amelioration of mitochondrial dynamics. Our overall findings demonstrate a significant impact of FM19G11-loaded NPs on muscle cell function and bioenergetic status in G93A-SOD1 myoblasts, thus promising to open new avenues towards possible adoption of FM19G11-based nanotherapies to slow muscle degeneration in the frame of ALS and muscle disorders.

Role of Nanoparticle-Conjugates and Nanotheranostics in Abrogating Oxidative Stress and Ameliorating Neuroinflammation

Oxidative stress is a deteriorating condition that arises due to an imbalance between the reactive oxygen species and the antioxidant system or defense of the body. The key reasons for the development of such conditions are malfunctioning of various cell organelles, such as mitochondria, endoplasmic reticulum, and Golgi complex, as well as physical and mental disturbances. The nervous system has a relatively high utilization of oxygen, thus making it particularly vulnerable to oxidative stress, which eventually leads to neuronal atrophy and death. This advances the development of neuroinflammation and neurodegeneration-associated disorders such as Alzheimer's disease, Parkinson's disease, epilepsy, dementia, and other memory disorders. It is imperative to treat such conditions as early as possible before they worsen and progress to irreversible damage. Oxidative damage can be negated by two mechanisms: improving the cellular defense system or providing exogenous antioxidants. Natural antioxidants can normally handle such oxidative stress, but they have limited efficacy. The valuable features of nanoparticles and/or nanomaterials, in combination with antioxidant features, offer innovative nanotheranostic tools as potential therapeutic modalities. Hence, this review aims to represent novel therapeutic approaches like utilizing nanoparticles with antioxidant properties and nanotheranostics as delivery systems for potential therapeutic applications in various neuroinflammation- and neurodegeneration-associated disease conditions.

Recent Advancements in Nanomaterials: A Promising Way to Manage Neurodegenerative Disorders

Neurodegenerative diseases (NDs) such as dementia, Alzheimer's disease, Parkinson's disease, frontotemporal dementia, and amyotrophic lateral sclerosis are some of the most prevalent disorders currently afflicting healthcare systems. Many of these diseases share similar pathological hallmarks, including elevated oxidative stress, mitochondrial dysfunction, protein misfolding, excitotoxicity, and neuroinflammation, all of which contribute to the deterioration of the nervous system's structure and function. The development of diagnostic and therapeutic materials in the monitoring and treatment of these diseases remains challenging. One of the biggest challenges facing therapeutic and diagnostic materials is the blood-brain barrier (BBB). The BBB is a multifunctional membrane possessing a plethora of biochemical, cellular, and immunological features that ensure brain homeostasis by preventing the entry and accumulation of unwanted compounds. With regards to neurodegenerative diseases, the recent application of tailored nanomaterials (nanocarriers and nanoparticles) has led to advances in diagnostics and therapeutics. In this review, we provide an overview of commonly used nanoparticles and their applications in NDs, which may offer new therapeutic strategies for the prevention and treatment of neurodegenerative diseases.

Nanoparticle-Based Drug Delivery Systems: An Inspiring Therapeutic Strategy for Neurodegenerative Diseases

Neurodegenerative diseases are common, incurable neurological disorders with high prevalence, and lead to memory, movement, language, and intelligence impairments, threatening the lives and health of patients worldwide. The blood-brain barrier (BBB), a physiological barrier between the central nervous system and peripheral blood circulation, plays an important role in maintaining the homeostasis of the intracerebral environment by strictly regulating the transport of substances between the blood and brain. Therefore, it is difficult for therapeutic drugs to penetrate the BBB and reach the brain, and this affects their efficacy. Nanoparticles (NPs) can be used as drug transport carriers and are also known as nanoparticle-based drug delivery systems (NDDSs). These systems not only increase the stability of drugs but also facilitate the crossing of drugs through the BBB and improve their efficacy. In this article, we provided an overview of the types and administration routes of NPs, highlighted the preclinical and clinical studies of NDDSs in neurodegenerative diseases, and summarized the combined therapeutic strategies in the management of neurodegenerative diseases. Finally, the prospects and challenges of NDDSs in recent basic and clinical research were also discussed. Above all, NDDSs provide an inspiring therapeutic strategy for the treatment of neurodegenerative diseases.

Nanotherapeutic and Stem Cell Therapeutic Strategies in Neurodegenerative Diseases: A Promising Therapeutic Approach

Neurodegeneration is characterized by progressive, disabling, and incurable neurological disorders with the massive loss of specific neurons. As one of the most promising potential therapeutic strategies for neurodegenerative diseases, stem cell therapy exerts beneficial effects through different mechanisms, such as direct replacement of damaged or lost cells, secretion of neurotrophic and growth factors, decreased neuroinflammation, and activation of endogenous stem cells. However, poor survival and differentiation rates of transplanted stem cells, insufficient homing ability, and difficulty tracking after transplantation limit their further clinical use. The rapid development of nanotechnology provides many promising nanomaterials for biomedical applications, which already have many applications in neurodegenerative disease treatment and seem to be able to compensate for some of the deficiencies in stem cell therapy, such as transport of stem cells/genes/drugs, regulating stem cell differentiation, and real-time tracking in stem cell therapy. Therefore, nanotherapeutic strategies combined with stem cell therapy is a promising therapeutic approach to treating neurodegenerative diseases. The present review systematically summarizes recent advances in stem cell therapeutics and nanotherapeutic strategies and highlights how they can be combined to improve therapeutic efficacy for the treatment of neurodegenerative diseases.

Innovative Discoveries in Neurosurgical Treatment of Neurodegenerative Diseases: A Narrative Review

Neurodegenerative diseases (NDDs) encapsulate conditions in which neural cell populations are perpetually degraded and nervous system function destroyed. Generally linked to increased age, the proportion of patients diagnosed with a NDD is growing as human life expectancies rise. Traditional NDD therapies and surgical interventions have been limited. However, recent breakthroughs in understanding disease pathophysiology, improved drug delivery systems, and targeted pharmacologic agents have allowed innovative treatment approaches to treat NDDs. A common denominator for administering these new treatment options is the requirement for neurosurgical skills. In the present narrative review, we highlight exciting and novel preclinical and clinical discoveries being integrated into NDD care. We also discuss the traditional role of neurosurgery in managing these neurodegenerative conditions and emphasize the critical role of neurosurgery in effectuating these newly developed treatments.

Nose-to-Brain: The Next Step for Stem Cell and Biomaterial Therapy in Neurological Disorders

Neurological disorders are a leading cause of morbidity worldwide, giving rise to a growing need to develop treatments to revert their symptoms. This review highlights the great potential of recent advances in cell therapy for the treatment of neurological disorders. Through the administration of pluripotent or stem cells, this novel therapy may promote neuroprotection, neuroplasticity, and neuroregeneration in lesion areas. The review also addresses the administration of these therapeutic molecules by the intranasal route, a promising, non-conventional route that allows for direct access to the central nervous system without crossing the blood–brain barrier, avoiding potential adverse reactions and enabling the administration of large quantities of therapeutic molecules to the brain. Finally, we focus on the need to use biomaterials, which play an important role as nutrient carriers, scaffolds, and immune modulators in the administration of non-autologous cells. Little research has been conducted into the integration of biomaterials alongside intranasally administered cell therapy, a highly promising approach for the treatment of neurological disorders.

Anti-Amyloidogenic and Fibril-Disaggregating Potency of the Levodopa-Functionalized Gold Nanoroses as Exemplified in a Diphenylalanine-Based Amyloid Model

The phenomenon of proteins/peptide assembly into amyloid fibrils is associated with various neurodegenerative and age-related human disorders. Inhibition of the aggregation behavior of amyloidogenic peptides/proteins or disruption of the pre-formed aggregates is a viable therapeutic option to control the progression of various protein aggregation-related disorders such as Alzheimer's disease (AD). In the current work, we investigated both the amyloid inhibition and disaggregation proclivity of levodopa-functionalized gold nanoroses (GNRs) against various peptide-based amyloid models, including the amyloid beta peptide [Aβ (1-42) and Aβ (1-40)] and the dipeptide phenylalanine-phenylalanine (FF). Our results depicted the anti-aggregation behavior of the GNR toward FF and both forms of Aβ-derived fibrils. The peptides demonstrated a variation in their fiber-like morphology and a decline in thioflavin T fluorescence after being co-incubated with the GNR. We further demonstrated the neuroprotective effects of the GNR in neuroblastoma cells against FF and Aβ (1-42) fiber-induced toxicity, exemplified both in terms of regaining cellular viability and reducing production of reactive oxygen species. Overall, these findings support the potency of the GNR as a promising platform for combating AD.

Nanoparticles in Combating Neuronal Dysregulated Signaling Pathways: Recent Approaches to the Nanoformulations of Phytochemicals and Synthetic Drugs Against Neurodegenerative Diseases

As the worldwide average life expectancy has grown, the prevalence of age-related neurodegenerative diseases (NDDs) has risen dramatically. A progressive loss of neuronal function characterizes NDDs, usually followed by neuronal death. Inflammation, apoptosis, oxidative stress, and protein misfolding are critical dysregulated signaling pathways that mainly orchestrate neuronal damage from a mechanistic point. Furthermore, in afflicted families with genetic anomalies, mutations and multiplications of α-synuclein and amyloid-related genes produce some kinds of NDDs. Overproduction of such proteins, and their excessive aggregation, have been proven in various models of neuronal malfunction and death. In this line, providing multi-target therapies carried by novel delivery systems would pave the road to control NDDs through simultaneous modulation of such dysregulated pathways. Phytochemicals are multi-target therapeutic agents, which employ several mechanisms towards neuroprotection. Besides, the blood-brain barrier (BBB) is a critical issue in managing NDDs since it inhibits the accessibility of drugs to the brain in sufficient concentration. Besides, discovering novel delivery systems is vital to improving the efficacy, bioavailability, and pharmacokinetic of therapeutic agents. Such novel formulations are also employed to improve the drug's biodistribution, allow for the co-delivery of several medicines, and offer targeted intracellular delivery against NDDs. The present review proposes nanoformulations of phytochemicals and synthetic agents to combat NDDs by modulating neuroinflammation, neuroapoptosis, neuronal oxidative stress pathways and protein misfolding.

The emerging role of noncoding RNAs in neuroinflammation: Implications in pathogenesis and therapeutic approaches

Noncoding RNAs (ncRNAs) are important regulators of gene expression in different cell processes. Due to their ability in monitoring neural development genes, these transcripts confer neurons with the potential to exert broad control over the expression of genes for performing neurobiological functions. Although the change of ncRNA expression in different neurodegenerative diseases has been reviewed elsewhere, only recent evidence drove our attention to unravel the involvement of these molecules in neuroinflammation within these devastating disorders. Remarkably, the interactions between ncRNAs and inflammatory pathways are not fully recognized. Therefore, this review has focused on the interplay between diverse inflammatory pathways and the related ncRNAs, including microRNAs, long noncoding RNAs, and competing endogenous RNAs in Alzheimer's disease, Parkinson's diseases, amyotrophic lateral sclerosis, epilepsy, multiple sclerosis, Huntington's disease, and prion diseases. Providing novel insights in the field of combining biomarkers is a critical step for using them as diagnostic tools and therapeutic targets in clinical settings.

Diversity of Adult Neural Stem and Progenitor Cells in Physiology and Disease

Adult neural stem and progenitor cells (NSPCs) contribute to learning, memory, maintenance of homeostasis, energy metabolism and many other essential processes. They are highly heterogeneous populations that require input from a regionally distinct microenvironment including a mix of neurons, oligodendrocytes, astrocytes, ependymal cells, NG2+ glia, vasculature, cerebrospinal fluid (CSF), and others. The diversity of NSPCs is present in all three major parts of the CNS, i.e., the brain, spinal cord, and retina. Intrinsic and extrinsic signals, e.g., neurotrophic and growth factors, master transcription factors, and mechanical properties of the extracellular matrix (ECM), collectively regulate activities and characteristics of NSPCs: quiescence/survival, proliferation, migration, differentiation, and integration. This review discusses the heterogeneous NSPC populations in the normal physiology and highlights their potentials and roles in injured/diseased states for regenerative medicine.

Non-Viral Vector-Mediated Gene Therapy for ALS: Challenges and Future Perspectives

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, for which no effective treatment is yet available to either slow or terminate it. Recent advances in gene therapy renew hope for developing an effective approach to control this disease. Non-viral vectors, such as lipid- and polymer-based nanoparticles, cationic polymers, and exosomes, can effectively transfer genes into primary neurons. The resulting gene expression can be long-term, stable, and without immunological complications, which is essential for the effective management of neurological disorders. This Review will first describe the current research and clinical stage of novel therapies for ALS. It will then touch on the journey of non-viral vector use in ALS, subsequently highlighting the application of non-viral vector-mediated gene therapy. The bottlenecks in the translation of non-viral vectors for ALS treatment are also discussed, including the biological barriers of systemic administration and the issues of "when, where, and how much?" for effective gene delivery. The prospect of employing emerging techniques, such as CRISPR-Cas9 gene editing, stem cell methodology, and low-intensity focused ultrasound for fueling the transport of non-viral vectors to the central nervous system for personalized gene therapy, is briefly discussed in the context of ALS. Despite the challenging road that lies ahead, with the current expansion in interest and technological advancement in non-viral vector-delivered gene therapy for ALS, we hold hope that the field is headed toward a positive future.

The Application of Nanotechnology for the Diagnosis and Treatment of Brain Diseases and Disorders

Brain is by far the most complex organ in the body. It is involved in the regulation of cognitive, behavioral, and emotional activities. The organ is also a target for many diseases and disorders ranging from injuries to cancers and neurodegenerative diseases. Brain diseases are the main causes of disability and one of the leading causes of deaths. Several drugs that have shown potential in improving brain structure and functioning in animal models face many challenges including the delivery, specificity, and toxicity. For many years, researchers have been facing challenge of developing drugs that can cross the physical (blood–brain barrier), electrical, and chemical barriers of the brain and target the desired region with few adverse events. In recent years, nanotechnology emerged as an important technique for modifying and manipulating different objects at the molecular level to obtain desired features. The technique has proven to be useful in diagnosis as well as treatments of brain diseases and disorders by facilitating the delivery of drugs and improving their efficacy. As the subject is still hot, and new research findings are emerging, it is clear that nanotechnology could upgrade health care systems by providing easy and highly efficient diagnostic and treatment methods. In this review, we will focus on the application of nanotechnology in the diagnosis and treatment of brain diseases and disorders by illuminating the potential of nanoparticles.

Biomaterials in Neurodegenerative Disorders: A Promising Therapeutic Approach

Neurodegenerative disorders (i.e., Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and spinal cord injury) represent a great problem worldwide and are becoming prevalent because of the increasing average age of the population. Despite many studies having focused on their etiopathology, the exact cause of these diseases is still unknown and until now, there are only symptomatic treatments. Biomaterials have become important not only for the study of disease pathogenesis, but also for their application in regenerative medicine. The great advantages provided by biomaterials are their ability to mimic the environment of the extracellular matrix and to allow the growth of different types of cells. Biomaterials can be used as supporting material for cell proliferation to be transplanted and as vectors to deliver many active molecules for the treatments of neurodegenerative disorders. In this review, we aim to report the potentiality of biomaterials (i.e., hydrogels, nanoparticles, self-assembling peptides, nanofibers and carbon-based nanomaterials) by analyzing their use in the regeneration of neural and glial cells their role in axon outgrowth. Although further studies are needed for their use in humans, the promising results obtained by several groups leads us to suppose that biomaterials represent a potential therapeutic approach for the treatments of neurodegenerative disorders.

Nanotechnology-based Targeting of Neurodegenerative Disorders: A Promising Tool for Efficient Delivery of Neuromedicines

Traditional drug delivery approaches remained ineffective in offering better treatment to various neurodegenerative disorders (NDs). In this context, diverse types of nanocarriers have shown their great potential to cross the blood-brain barrier (BBB) and have emerged as a prominent carrier system in drug delivery. Moreover, nanotechnology-based methods usually involve numerous nanosized carrier platforms, which potentiate the effect of the therapeutic agents in the therapy of NDs especially in diagnosis and drug delivery with negligible side effects. In addition, nanotechnology-based techniques have offered several strategies to cross BBB to intensify the bioavailability of drug moieties in the brain. In the last few years, diverse kinds of nanoparticles (NPs) have been developed by incorporating various biocompatible components (e.g., polysaccharide-based NPs, polymeric NPs, selenium NPs, AuNPs, protein-based NPs, gadolinium NPs, etc.), that showed great therapeutic benefits against NDs. Eventually, this review provides deep insights to explore recent applications of some innovative nanocarriers enclosing active molecules for the efficient treatment of NDs.

Ependymal cells in the spinal cord as neuronal progenitors

Ependymal cells are neural progenitors and form part of the central canal of the spinal cord. Therefore, ependymal cells could serve as a potential source of neural progenitors for regenerative medicine applications. Such applications consist of endogenous activation or exogenous transplantation, alone or in combination with pharmacological treatments, to repair spinal cord injuries. This mini review describes the main phenotypical characteristics of ependymal cells from spinal cord and the opportunities offered for spinal cord injury therapeutic application.

Mitochondrial dysfunction and energy deprivation in the mechanism of neurodegeneration

Energy-producing organelles mitochondria are involved in a number of cellular functions. Deregulation of mitochondrial function due to mutations or effects of mitochondrial toxins is proven to be a trigger for diverse pathologies, including neurodegenerative disorders. Despite the extensive research done in the last decades, the mechanisms by which mitochondrial dysfunction leads to neuronal deregulation and cell death have not yet been fully elucidated. Brain cells are specifically dependent on mitochondria due to their high energy demands to maintain neuronal ion gradients and signal transduction, and also, to mediate neuronal health through the processes of mitochondrial calcium homeostasis, mitophagy, mitochondrial reactive oxygen species production and mitochondrial dynamics. Some of these processes have been independently implicated in the mechanism of neuronal loss in neurodegeneration. Moreover, it is increasingly recognised that these processes are interdependent and interact within the mitochondria to ensure proper neuronal function and survival.