Multi-functional platelet membrane-camouflaged nanoparticles reduce neuronal apoptosis and regulate microglial phenotype during ischemic injury

Platelet membrane-camouflaged bioactive glass nano-formulations for enhanced drug delivery in the treatment of acute arterial thrombosis

Thrombus treatment remains a significant challenge, primarily due to factors such as the short half-life of thrombolytic agents, suboptimal drug utilization, and limited therapeutic efficacy. In this study, we developed a platelet membrane-camouflaged bioactive glass nanoparticles (BGs) as drug carriers to load thrombolytic agent urokinase (UK) and anticoagulant drug tirofiban (TF). UK and TF were firstly incorporated onto BGs, and followed by a camouflage of polydopamine (PDA) and platelet membrane (PM) to form composite nano-formulation (TUBGs@PP). This composite nano-formulation leverages the PM camouflage to enhance its biocompatibility, prolong circulation time in vivo, and extend the half-life of drugs. Additionally, as-fabricated TUBGs@PP composite nano-formulation can circumvent immune system-mediated clearance, thereby facilitating targeted drug delivery to the thrombus sites and enhancing the thrombolytic efficacy. In vivo results demonstrated that the TUBGs@PP composite nano-formulations not only prolonged circulation time but also effectively unclogged blood vessels at the site of thrombosis, while reducing recurrence of thrombosis and drug side effects. STATEMENT OF SIGNIFICANCE: The platelet membrane-camouflaged bioactive glass nanoparticles as drug carriers for the synergistic co-delivery of urokinase and tirofiban have been developed (TUBGs@PP) for the treatment of acute arterial thrombosis. This cutting-edge therapeutic strategy addresses several critical limitations inherent in current thrombolytic treatments, including the transient half-life of thrombolytic agents, suboptimal drug bioavailability, and limited therapeutic efficacy. In vivo studies demonstrate that TUBGs@PP not only achieves sustained circulation but also effectively restores vascular patency at thrombotic loci, concurrently reducing the risk of thrombotic recurrence and minimizing adverse drug effects. This study highlights the paradigm-shifting potential of TUBGs@PP in thrombolytic therapy, offering a transformative solution to existing challenges and promising to markedly improve clinical outcomes for patients.

Nanoparticles Designed Based on the Blood-Brain Barrier for the Treatment of Cerebral Ischemia-Reperfusion Injury

Cerebral ischemia-reperfusion injury (CI/RI) is currently considered a significant factor affecting the prognosis of ischemic stroke. The blood-brain barrier (BBB) plays multiple roles in the treatment ofCI/RI. BBB leakage allows bloodborne toxins to exacerbate the stroke pathology. Yet as the physiological barrier that separates the blood from the brain, BBB also poses a significant obstacle to therapeutic drug delivery. Therefore, it is essential to consider both crossing and repairing the BBB in the process of the treatment of CI/RI. Leveraging the exceptional benefits of nanoparticles (NPs) for BBB penetration and targeted repair, numerous NPs are developed as promising drug delivery platforms. Considering the complex role of the BBB in CI/RI, this review delves into the strategies for designing NPs to cross the BBB, focusing on peptide-modified NPs, cell-mediated NPs, cell membrane-derived NPs, and BBB-modulating NPs. Additionally, it summarizes design strategies of NPs targeting endothelial cells (ECs), astrocytes, and those aimed at regulating the microenvironment to repair the BBB. On this basis, it reveals the prospects and challenges of NPs designed around the BBB in CI/RI treatment. And it highlights the need to combine BBB permeability promotion and BBB repair in nanoparticle strategies designed based on the BBB to achieve more effective treatment.

Retrospective perspectives and future trends in nanomedicine treatment: from single membranes to hybrid membranes

At present, various diseases seriously threaten human life and health, and the development of nanodrug delivery systems has brought about a turnaround for traditional drug treatments, with nanoparticles being precisely targeted to improve bioavailability. Surface modification of nanoparticles can prolong blood circulation time and enhance targeting ability. The application of cell membrane-coated nanoparticles further improves their biocompatibility and active targeting ability, providing new hope for the treatment of various diseases. Various types of cell membrane biomimetic nanoparticles have gradually attracted increasing attention due to their unique advantages. However, the pathological microenvironment of different diseases is complex and varied, and the single-cell membrane has several limitations because a single functional property cannot fully meet the requirements of disease treatment. Hybrid cell membranes integrate the advantages of multiple biological membranes and have become an emerging research hotspot. This review summarizes the application of cell membrane biomimetic nanoparticles in the treatment of various diseases and discusses the advantages, challenges and future development of biomimetic nanoparticles. We propose that the fusion of multiple membranes may be a reasonable trend in the future to provide some ideas and directions for the treatment of various diseases.

Hybrid Membrane Biomimetic Photothermal Nanorobots for Enhanced Chemodynamic-Chemotherapy-Immunotherapy

Glioblastoma multiforme (GBM) is a highly invasive and fatal brain tumor with a grim prognosis, where current treatment modalities, including postoperative radiotherapy and temozolomide chemotherapy, yield a median survival of only 15 months. The challenges of tumor heterogeneity, drug resistance, and the blood-brain barrier necessitate innovative therapeutic approaches. This study introduces a strategy employing biomimetic magnetic nanorobots encapsulated with hybrid membranes derived from platelets and M1 macrophages to enhance blood-brain barrier penetration and target GBM. The nanorobots encapsulate a polypyrrole/Fe3O4 nanocomplex (PPy@F) for photothermal therapy (PTT) and promote the Fenton reaction of Fe3O4 to generate chemodynamic therapy (CDT). Additionally, temozolomide and PD-L1 antibody (SNTSESF) act as chemotherapy drug and immune checkpoint inhibitor, respectively. The biomimetic design leverages the functional properties of cell membranes to improve the blood residence time and tumor targeting. The integration of PTT and CDT aims to transform "cold" tumors into "hot" tumors, thereby enhancing immunotherapeutic efficacy. This multifaceted approach, PTT, CT, CDT, and immune checkpoint blockade therapy, offers a promising strategy for the treatment of GBM.

Cell Membrane Camouflaged Biomimetic Nanoparticles as a Versatile Platform for Brain Diseases Treatment

Although there are various advancements in biomedical in the past few decades, there are still challenges in the treatment of brain diseases. The main difficulties are the inability to deliver a therapeutic dose of the drug to the brain through the blood-brain barrier (BBB) and the serious side effects of the drug. Thus, it is essential to select biocompatible drug carriers and novel therapeutic tools to better enhance the effect of brain disease treatment. In recent years, biomimetic nanoparticles (BNPs) based on natural cell membranes, which have excellent biocompatibility and low immunogenicity, are widely used in the treatment of brain diseases to enable the drug to successfully cross the BBB and target brain lesions. BNPs can prolong the circulation time in vivo, are more conducive to drug aggregation in brain lesions. Cell membranes (CMs) from cancer cells (CCs), red blood cells (RBCs), white blood cells (WBCs), and so on are used as biomimetic coatings for nanoparticles (NPs) to achieve the ability to target, evade clearance, or stimulate the immune system. This review summarizes the application of different cell sources as BNPs coatings in the treatment of brain diseases and discusses the possibilities and challenges of clinical translation.

The application of nanoparticles in delivering small RNAs for cancer therapy

Small molecular RNAs, including microRNA (miRNA) and small interfering RNA (siRNA), participate in the regulation of gene expression. As powerful regulators, miRNAs, take part in posttranscriptional regulation of gene expression and play important roles in the diagnosis and treatment of cancer. Meanwhile, siRNA can induce sequence-specific gene silencing, thus being able to inhibit tumorigenesis by suppressing the expression of their targeted proto-oncogenes. Small RNAs (including naked miRNAs and siRNAs) are easily degraded by circulating RNAase, which can be retarded through the package of nanoparticles. Therefore, nanoparticles help tumor therapy by regulating targeted genes of small RNAs. Here, we reviewed the effects of small RNAs on gene expression; the advantages, disadvantages, and targeted modification of nanoparticles as carriers transporting small RNAs; and the application of nanocarriers delivering small RNA for cancer-targeted therapy.

An Overview on the Physiopathology of the Blood-Brain Barrier and the Lipid-Based Nanocarriers for Central Nervous System Delivery

The state of well-being and health of our body is regulated by the fine osmotic and biochemical balance established between the cells of the different tissues, organs, and systems. Specific districts of the human body are defined, kept in the correct state of functioning, and, therefore, protected from exogenous or endogenous insults of both mechanical, physical, and biological nature by the presence of different barrier systems. In addition to the placental barrier, which even acts as a linker between two different organisms, the mother and the fetus, all human body barriers, including the blood-brain barrier (BBB), blood-retinal barrier, blood-nerve barrier, blood-lymph barrier, and blood-cerebrospinal fluid barrier, operate to maintain the physiological homeostasis within tissues and organs. From a pharmaceutical point of view, the most challenging is undoubtedly the BBB, since its presence notably complicates the treatment of brain disorders. BBB action can impair the delivery of chemical drugs and biopharmaceuticals into the brain, reducing their therapeutic efficacy and/or increasing their unwanted bioaccumulation in the surrounding healthy tissues. Recent nanotechnological innovation provides advanced biomaterials and ad hoc customized engineering and functionalization methods able to assist in brain-targeted drug delivery. In this context, lipid nanocarriers, including both synthetic (liposomes, solid lipid nanoparticles, nanoemulsions, nanostructured lipid carriers, niosomes, proniosomes, and cubosomes) and cell-derived ones (extracellular vesicles and cell membrane-derived nanocarriers), are considered one of the most successful brain delivery systems due to their reasonable biocompatibility and ability to cross the BBB. This review aims to provide a complete and up-to-date point of view on the efficacy of the most varied lipid carriers, whether FDA-approved, involved in clinical trials, or used in in vitro or in vivo studies, for the treatment of inflammatory, cancerous, or infectious brain diseases.

Nanomaterials as Microglia Modulators in the Treatment of Central Nervous System Disorders

Microglia play a pivotal role in the central nervous system (CNS) homeostasis, acting as housekeepers and defenders of the surrounding environment. These cells can elicit their functions by shifting into two main phenotypes: pro-inflammatory classical phenotype, M1, and anti-inflammatory alternative phenotype, M2. Despite their pivotal role in CNS homeostasis, microglia phenotypes can influence the development and progression of several CNS disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, ischemic stroke, traumatic brain injuries, and even brain cancer. It is thus clear that the possibility of modulating microglia activation has gained attention as a therapeutic tool against many CNS pathologies. Nanomaterials are an unprecedented tool for manipulating microglia responses, in particular, to specifically target microglia and elicit an in situ immunomodulation activity. This review focuses the discussion on two main aspects: analyzing the possibility of using nanomaterials to stimulate a pro-inflammatory response of microglia against brain cancer and introducing nanostructures able to foster an anti-inflammatory response for treating neurodegenerative disorders. The final aim is to stimulate the analysis of the development of new microglia nano-immunomodulators, paving the way for innovative and effective therapeutic approaches for the treatment of CNS disorders.

Advanced Nano-Drug Delivery Systems in the Treatment of Ischemic Stroke

In recent years, the frequency of strokes has been on the rise year by year and has become the second leading cause of death around the world, which is characterized by a high mortality rate, high recurrence rate, and high disability rate. Ischemic strokes account for a large percentage of strokes. A reperfusion injury in ischemic strokes is a complex cascade of oxidative stress, neuroinflammation, immune infiltration, and mitochondrial damage. Conventional treatments are ineffective, and the presence of the blood-brain barrier (BBB) leads to inefficient drug delivery utilization, so researchers are turning their attention to nano-drug delivery systems. Functionalized nano-drug delivery systems have been widely studied and applied to the study of cerebral ischemic diseases due to their favorable biocompatibility, high efficiency, strong specificity, and specific targeting ability. In this paper, we briefly describe the pathological process of reperfusion injuries in strokes and focus on the therapeutic research progress of nano-drug delivery systems in ischemic strokes, aiming to provide certain references to understand the progress of research on nano-drug delivery systems (NDDSs).

A One-Stone-Two-Birds Strategy of Targeting Microbubbles with "Dual" Anti-Inflammatory and Blood-Brain Barrier "Switch" Function for Ischemic Stroke Treatment

Inflammation is considered to be the main target of the development of new stroke therapies. There are three key issues in the treatment of stroke inflammation: the first one is how to overcome the blood-brain barrier (BBB) to achieve drug delivery, the second one is how to select drugs to treat stroke inflammation, and the third one is how to achieve targeted drug delivery. In this study, we constructed hydrocortisone-phosphatidylserine microbubbles and combined them with ultrasound (US)-targeted microbubble destruction technology to successfully open the BBB to achieve targeted drug delivery. Phosphatidylserine on the microbubbles was used for its "eat me" effect to increase the targeting of the microvesicles. In addition, we found that hydrocortisone can accelerate the closure of the BBB, achieving efficient drug delivery while reducing the entry of peripheral toxins into the brain. In the treatment of stroke inflammation, it was found that hydrocortisone itself has anti-inflammatory effects and can also change the polarization of microglia from the harmful pro-inflammatory M1 phenotype to the beneficial anti-inflammatory M2 phenotype, thus achieving dual anti-inflammatory effects and enhancing the anti-inflammatory effects in ischemic areas after stroke, well reducing the cerebellar infarction volume by inhibiting the inflammatory response after cerebral ischemia. A confocal microendoscope was used to directly observe the polarization of microglial cells in living animal models for dynamic microscopic visualization detection showing the advantage of being closer to clinical work. Taken together, this study constructed a multifunctional targeted US contrast agent with the function of "one-stone-two-birds", which can not only "on-off" the BBB but also have "two" anti-inflammatory functions, providing a new strategy of integrated anti-inflammatory targeted delivery and imaging monitoring for ischemic stroke treatment.

Cell Membrane-Derived Nanovehicles for Targeted Therapy of Ischemic Stroke: From Construction to Application

Ischemic stroke (IS) is a prevalent form of stroke and a leading cause of mortality and disability. Recently, cell membrane-derived nanovehicles (CMNVs) derived from erythrocytes, thrombocytes, neutrophils, macrophages, neural stem cells, and cancer cells have shown great promise as drug delivery systems for IS treatment. By precisely controlling drug release rates and targeting specific sites in the brain, CMNVs enable the reduction in drug dosage and minimization of side effects, thus significantly enhancing therapeutic strategies and approaches for IS. While there are some reviews regarding the applications of CMNVs in the treatment of IS, there has been limited attention given to important aspects such as carrier construction, structural design, and functional modification. Therefore, this review aims to address these key issues in CMNVs preparation, structural composition, modification, and other relevant aspects, with a specific focus on targeted therapy for IS. Finally, the challenges and prospects in this field are discussed.

Living Cells and Cell-Derived Vesicles: A Trojan Horse Technique for Brain Delivery

Brain diseases remain a significant global healthcare burden. Conventional pharmacological therapy for brain diseases encounters huge challenges because of the blood-brain barrier (BBB) limiting the delivery of therapeutics into the brain parenchyma. To address this issue, researchers have explored various types of drug delivery systems. Cells and cell derivatives have attracted increasing interest as "Trojan horse" delivery systems for brain diseases, owing to their superior biocompatibility, low immunogenicity, and BBB penetration properties. This review provided an overview of recent advancements in cell- and cell-derivative-based delivery systems for the diagnosis and treatment of brain diseases. Additionally, it discussed the challenges and potential solutions for clinical translation.

Harnessing nanobiotechnology for cerebral ischemic stroke management

Cerebral ischemic stroke remains one of the most serious neurological disorders that pose threats to human health, causing a large amount of long-term disability or even death throughout the world. Based on its physiologic and pathological features, there are limited available therapeutic options for effective ischemic stroke management. Encouragingly, a rapid advancement of nanobiotechnology is bringing new insights into exploring more alternative strategies against cerebral ischemic stroke, which can cleverly overcome the limitations related to conventional treatment methods. Therefore, this review focuses on the recent achievements of nanobiotechnology for ischemic stroke management, which emphasizes diverse targeted delivery strategies using various nanoplatforms including liposomes, micelles, polymeric nanoparticles, nanogels, inorganic nanomaterials, and cell-derived nano-vectors based on the pathophysiological features of ischemic stroke. Moreover, different therapeutic approaches against ischemic stroke such as neuroprotection, anti-inflammation, thrombolysis, increased blood-brain barrier penetration and reactive oxygen species scavenging are highlighted. Meanwhile, this review discusses how these versatile nanoplatforms were designed to assist in the treatment of ischemic stroke. Based on this, challenges, opportunities, and future perspectives using nanobiotechnology through rational design for effective ischemic stroke management are revealed.