Fibrin-Targeted Nanoparticles for Finding, Visualizing and Characterizing Blood Clots in Acute Ischemic Stroke

Nanocarrier Drug Release and Blood-Brain Barrier Penetration at Post-Stroke Microthrombi Monitored by Real-Time Förster Resonance Energy Transfer

Nanotechnology holds great promise for improving the delivery of therapeutics to the brain. However, current approaches often operate at the organ or tissue level and are limited by the lack of tools to dynamically monitor cargo delivery in vivo. We have developed highly fluorescent lipid nanodroplets (LNDs) that enable tracking of nanocarrier behavior at the subcellular level while also carrying a Förster resonance energy transfer (FRET)-based drug delivery detection system (FedEcs) capable of monitoring cargo release in vivo. Using two-photon microscopy, we demonstrate that circulating LNDs in naïve mouse brain vasculature exhibit 3D real-time FRET changes, showing size-dependent stability over 2 h in blood circulation. Further, in the Nanostroke model, dynamic intravital two-photon imaging revealed that LNDs accumulated within cerebral postischemic microthrombi, where they released their cargo significantly faster than in normal blood circulation. Furthermore, the blood-brain barrier (BBB) became permeable at the microclot sites thereby allowing accumulated FedEcs-LNDs to cross the BBB and deliver their cargo to the brain parenchyma. This microthrombi-associated translocation was confirmed at the ultrastructural level via volume-correlative light-electron microscopy. Consequently, FedEcs represents an advanced tool to quantitatively study the biodistribution and cargo release of nanocarriers at high resolution in real-time. By enabling us to resolve passive targeting mechanisms poststroke, specifically, accumulation, degradation, and extravasation via poststroke microthrombi, this system could significantly enhance the translational validation of nanocarriers for future treatments of brain diseases.

Nanotechnology in retinal diseases: From disease diagnosis to therapeutic applications

Nanotechnology has demonstrated tremendous promise in the realm of ocular illnesses, with applications for disease detection and therapeutic interventions. The nanoscale features of nanoparticles enable their precise interactions with retinal tissues, allowing for more efficient and effective treatments. Because biological organs are compatible with diverse nanomaterials, such as nanoparticles, nanowires, nanoscaffolds, and hybrid nanostructures, their usage in biomedical applications, particularly in retinal illnesses, has increased. The use of nanotechnology in medicine is advancing rapidly, and recent advances in nanomedicine-based diagnosis and therapy techniques may provide considerable benefits in addressing the primary causes of blindness related to retinal illnesses. The current state, prospects, and challenges of nanotechnology in monitoring nanostructures or cells in the eye and their application to regenerative ophthalmology have been discussed and thoroughly reviewed. In this review, we build on our previously published review article in 2021, where we discussed the impact of nano-biomaterials in retinal regeneration. However, in this review, we extended our focus to incorporate and discuss the application of nano-biomaterials on all retinal diseases, with a highlight on nanomedicine-based diagnostic and therapeutic research studies.

Assessment of Mannitol-Induced Chronic Blood-Brain Barrier Dysfunction In Vivo Using Magnetic Resonance

The blood-brain barrier (BBB) is essential for protection and plays a crucial role in chronic neurological disorders like small-vessel disease and Alzheimer's disease. Its complexity poses significant challenges for effective diagnostics and treatments, highlighting the need for novel animal models and comprehensive BBB dysfunction studies. This study investigates chronic BBB dysfunction induction using osmotic disruption via mannitol in healthy adult male Sprague Dawley rats over 12 weeks. Group 1 received 1 bolus/week (2.0 g/kg), Group 2 received 3 boluses/week (1.5 g/kg), and Group 3 received 3 boluses/week (2.5 g/kg). BBB dysfunction was assessed using gadolinium (Gd) infusion and MRI to evaluate location, severity, evolution, and persistence. MR spectroscopy (MRS) examined the brain metabolism changes due to intravenous mannitol, with T2-weighted MRI assessing brain lesions. Biomarkers of neuroinflammation were analyzed in the highest mannitol dose group. Our data show chronic BBB dysfunction primarily in the cortex, hippocampus, and striatum, but not in the corpus callosum of rats under periodic mannitol dosing in groups 1 and 2. MRS identified a distinctive metabolite signature, including changes in alanine, choline, and N-acetyl aspartate in the striatum of Group 1. No significant differences were found in the serum levels of all pro- and anti-inflammatory cytokines analyzed in the high-dose Group 3. This study underscores the feasibility and implications of using osmotic disruption to model chronic BBB dysfunction, offering insights for future neuroprotection and therapeutic strategies research.

Impact of Surface Ligand on the Biocompatibility of InP/ZnS Quantum Dots with Platelets

InP/ZnS quantum dots (QDs) have received a large focus in recent years as a safer alternative to heavy metal-based QDs. Given their intrinsic fluorescent imaging capabilities, these QDs can be potentially relevant for in vivo platelet imaging. The InP/ZnS QDs are synthesized and their biocompatibility investigated through the use of different phase transfer agents. Analysis of platelet function indicates that platelet-QD interaction can occur at all concentrations and for all QD permutations tested. However, as the QD concentration increases, platelet aggregation is induced by QDs alone independent of natural platelet agonists. This study helps to define a range of concentrations and coatings (thioglycolic acid and penicillamine) that are biocompatible with platelet function. With this information, the platelet-QD interaction can be identified using multiple methods. Fluorescent lifetime imaging microscopy (FLIM) and confocal studies have shown QDs localize on the surface of the platelet toward the center while showing evidence of energy transfer within the QD population. It is believed that these findings are an important stepping point for the development of fluorescent probes for platelet imaging.

The Photothrombotic Model of Ischemic Stroke

Stroke is a major cause of morbidity worldwide; yet, there is a lack of treatment options to address post-stroke cognitive and motor impairment, thus there is an urgency for developing neuroprotective and restorative therapies. Much of our fundamental understanding of stroke pathology has been derived from animal models. The photothrombotic model of ischemic stroke is commonly used to study cellular and molecular mechanisms of neurodegeneration, test functional/cognitive outcomes, identify important biomarkers, and assess the effectiveness of novel therapies. It allows for the precise targeting of an infarct to a specific region of the brain, has a low mortality rate, low seizure rate, and is relatively easy to perform. This chapter outlines materials and methods for the photothrombotic model of ischemic stroke in mice, its limitations, and some considerations needed when using this model.

Current trends and future perspectives of stroke management through integrating health care team and nanodrug delivery strategy

Stroke is accounted as the second-most mortality and adult disability factor in worldwide, while causes the bleeding promptly and lifetime consequences. The employed functional recovery after stroke is highly variable, allowing to deliver proper interventions to the right stroke patient at a specific time. Accordingly, the multidisciplinary nursing team, and the administrated drugs are major key-building-blocks to enhance stroke treatment efficiency. Regarding the healthcare team, adequate continuum of care have been declared as an integral part of the treatment process from the pre-hospital, in-hospital, to acute post-discharge phases. As a curative perspective, drugs administration is also vital in surviving at the early step and reducing the probability of disabilities in later. In this regard, nanotechnology-based medicinal strategy is exorbitantly burgeoning. In this review, we have highlighted the effectiveness of current clinical care considered by nursing teams to treat stroke. Also, the advancement of drugs through synthesis of miniaturized nanodrug formations relating stroke treatment is remarked. Finally, the remained challenges toward standardizing the healthcare team and minimizing the nanodrugs downsides are discussed. The findings ensure that future works on normalizing the healthcare nursing teams integrated with artificial intelligence technology, as well as advancing the operative nanodrugs can provide value-based stroke cares.

Integrative Approaches in Acute Ischemic Stroke: From Symptom Recognition to Future Innovations

Among the high prevalence of cerebrovascular diseases nowadays, acute ischemic stroke stands out, representing a significant worldwide health issue with important socio-economic implications. Prompt diagnosis and intervention are important milestones for the management of this multifaceted pathology, making understanding the various stroke-onset symptoms crucial. A key role in acute ischemic stroke management is emphasizing the essential role of a multi-disciplinary team, therefore, increasing the efficiency of recognition and treatment. Neuroimaging and neuroradiology have evolved dramatically over the years, with multiple approaches that provide a higher understanding of the morphological aspects as well as timely recognition of cerebral artery occlusions for effective therapy planning. Regarding the treatment matter, the pharmacological approach, particularly fibrinolytic therapy, has its merits and challenges. Endovascular thrombectomy, a game-changer in stroke management, has witnessed significant advances, with technologies like stent retrievers and aspiration catheters playing pivotal roles. For select patients, combining pharmacological and endovascular strategies offers evidence-backed benefits. The aim of our comprehensive study on acute ischemic stroke is to efficiently compare the current therapies, recognize novel possibilities from the literature, and describe the state of the art in the interdisciplinary approach to acute ischemic stroke. As we aspire for holistic patient management, the emphasis is not just on medical intervention but also on physical therapy, mental health, and community engagement. The future holds promising innovations, with artificial intelligence poised to reshape stroke diagnostics and treatments. Bridging the gap between groundbreaking research and clinical practice remains a challenge, urging continuous collaboration and research.

Peptide-metal nanohybrids (PMN): Promising entities for combating neurological maladies

Nanotherapeutics are gaining traction in the modern scenario because of their unique and distinct properties which separate them from macro materials. Among the nanoparticles, metal NPs (MNPs) have gained importance due to their distinct physicochemical and biological characteristics. Peptides also exhibit several important functions in humans. Different peptides have received approval as pharmaceuticals, and clinical trials have been commenced for several peptides. Peptides are also used as targeting ligands. Considering all the advantages offered by these two entities, the conjugation of MNPs with peptides has emerged as a potential strategy for achieving successful targeting, diagnosis, and therapy of various neurological pathologies.

Novel Nanoparticle-Based Treatment and Imaging Modalities

Over the last twenty years, nanomaterials have been widely used in cancer research [...].