Mitochondrial-targeted and ROS-responsive nanocarrier via nose-to-brain pathway for ischemic stroke treatment

Mechanistic insights of neuronal death and neuroprotective therapeutic approaches in stroke

Stroke, particularly ischemic stroke, is the leading cause of long-term disability and mortality worldwide. It occurs due to the occlusion of the cerebral arteries, which significantly reduces the delivery of blood, oxygen, and essential nutrients to brain tissues. This deprivation triggers a cascade of cellular events that ultimately leads to neuronal death. Recent studies have clarified the multifactorial pathogenesis of ischemic stroke, highlighting the roles of energy failure, excitotoxicity, oxidative stress, neuroinflammation, and apoptosis. This review aimed to provide a comprehensive insight into the fundamental mechanisms driving neuronal death triggered by ischemia and to examine the progress of neuroprotective therapeutic approaches designed to mitigate neuronal loss and promote neurological recovery after a stroke. Additionally, we explored widely accepted findings regarding the potential pathways implicated in neuronal death during ischemic stroke, including the interplay of apoptosis, autophagy, pyroptosis, ferroptosis, and necrosis, which collectively influence neuronal fate. We also discussed advancements in neuroprotective therapeutics, encompassing a range of interventions from pharmacological modulation to stem cell-based therapies, aimed at reducing neuronal injury and enhancing functional recovery following ischemic stroke. Despite these advancements, challenges remain in translating mechanistic insights into effective clinical therapies. Although neuroprotective strategies have shown promise in preclinical models, their efficacy in human trials has been inconsistent, often due to the complex pathology of ischemic stroke and the timing of interventions. In conclusion, this review synthesizes mechanistic insights into the intricate interplay of molecular and cellular pathways driving neuronal death post-ischemia. It sheds light on cutting-edge advancements in potential neuroprotective therapeutics, underscores the promise of regenerative medicine, and offers a forward-looking perspective on potential clinical breakthroughs. The ongoing evolution of precision-targeted interventions is expected to significantly enhance preventative strategies and improve clinical outcomes.

Exosomes in stroke management: A promising paradigm shift in stroke therapy

Effective treatment methods for stroke, a common cerebrovascular disease with a high mortality rate, are still being sought. Exosome therapy, a form of acellular therapy, has demonstrated promising efficacy in various diseases in animal models; however, there is currently insufficient evidence to guide the clinical application of exosome in patients with stroke. This article reviews the progress of exosome applications in stroke treatment. It aims to elucidate the significant potential value of exosomes in stroke therapy and provide a reference for their clinical translation. At present, many studies on exosome-based therapies for stroke are actively underway. Regarding preclinical research, exosomes, as bioactive substances with diverse sources, currently favor stem cells as their origin. Due to their high plasticity, exosomes can be effectively modified through various physical, chemical, and genetic engineering methods to enhance their efficacy. In animal models of stroke, exosome therapy can reduce neuroinflammatory responses, alleviate oxidative stress damage, and inhibit programmed cell death. Additionally, exosomes can promote angiogenesis, repair and regenerate damaged white matter fiber bundles, and facilitate the migration and differentiation of neural stem cells, aiding the repair process. We also summarize new directions for the application of exosomes, specifically the exosome intervention through the ventricular-meningeal lymphatic system. The review findings suggest that the treatment paradigm for stroke is poised for transformation.

Molecularly imprinted nanoparticles hitchhiking on neutrophils for precise treatment of ischemic stroke

Ischemic stroke (IS), the most prevalent type of stroke worldwide, is associated with a variety of complex processes, including oxidative stress, apoptosis, and ferroptosis. Recent findings indicate that inhibiting iron overload as a key regulatory mechanism of ferroptosis profoundly influences the pathogenesis and treatment of IS. In addition, enhanced blood-brain barrier (BBB) penetration and precise targeting of the ischaemic site contribute to improved therapeutic outcomes in IS. In this study, we developed FeSO4 templated-molecularly imprinted nanoparticles (MINPs) with high-affinity recognition of ferrous ions (Fe2+). MINPs exhibited physicochemical properties that perfectly match the polarity and condensed structure of Fe2+, resulting in the effective and specific clearance of Fe2+ through efficient and selective adsorption both in vivo and in vitro. Moreover, MINPs hitchhiked circulating neutrophils, thereby facilitating their penetration through BBB and enhancing targeted delivery to the ischemic brain. Our results, supported by transcriptomic analysis, further elucidated the molecular mechanisms by which MINPs significantly inhibit ferroptosis while concurrently regulating apoptosis and inflammation, thereby conferring marked neuroprotection against IS.

Mesenchymal Stem Cell-Derived Mitochondrial Transfer Promotes Tip Cell Phenotype via Glutathione Metabolic Reprogramming in Stroke Mice

Angiogenesis is crucial to improving neurovascular remodeling poststroke. Therein, the transformation of endothelial cells (ECs) to tip cells is essential in initiating angiogenesis. Mitochondrial damage in ECs poststroke and associated metabolic disorder are key factors repressing angiogenesis, but the mechanisms are unknown. Here, we designed an Arg-Gly-Asp peptide (RGD)-modified, mitochondria-enriched, and extracellular vesicle mimetics (mitoEVMs) platform for mitochondrial transfer. RGD mediated the mesenchymal stem cell-derived mitochondria transfer to ECs around the lesion targetedly. We found MSC-derived mitochondria promoted tip cell transition and further stimulated angiogenesis after stroke, alleviated brain atrophy, and improved functional rehabilitation. We noticed mitochondrial transfer rescued mitochondrial function in ECs and reprogrammed glutathione metabolism to activate the mTORC1 pathway, upregulated the expression of p4E-BP1 and VEGFR2, and ultimately facilitated tip cell transition. Our work elucidates the mechanism of MSC-derived mitochondrial transfer in poststroke treatment and proposes a potential approach for rehabilitation after stroke.

Construction of fibromodulin and borneol-clacked phosphorus dendrimer nanoparticles to reduce inflammation and oxidative stress in BBB to nursing care and ischemic stroke therapy

The formulation of novel multi-target combination therapies to address ischemic stroke (ICS) continues to pose significant challenges. This work presents a proof-of-concept display of a proficient nanomedicine formulation consisting of macrophage membrane (MM)-camouflaged phosphorous dendrimer (designated as PD)/fibromodulin (FB) nanoparticles (NPs) clacked with the antioxidant borneol (BN) to regulate both microglia and neurons for efficient ICS therapy. The developed MM@PD-FB/BN NPs, averaging 260 nm in size, exhibit excellent colloidal stability, prolonged BN release kinetics, and favorable cytocompatibility. Due to MM decoration, the MM@PD-FB/BN NPs can traverse the blood-brain barrier, influence microglia to produce anti-inflammatory (PD and FB) and antioxidative (FB and BN) effects in vitro, facilitating oxidative stress mitigation, microglia M2 polarization, and decreased proinflammatory cytokine secretion, while also acting on neuronal cells to exhibit anti-apoptotic properties. In a middle cerebral artery occlusion (MCAO) model, engineered MM@PD-FB/BN NPs demonstrate improved antioxidant, anti-inflammatory, and anti-apoptotic therapeutic effects, modulating the brain microenvironment to restore blood flow. The engineered MM-coated NPs, comprising active components of phosphorous dendrimers, FB, and BN, capable of comprehensively modulating the brain's inflammatory milieu, may broaden the treatment and nursing care of ischemic stroke.

Borate-modified recombinant type XVII collagen microneedles loaded with IGF-1 for the treatment of androgenetic alopecia

Androgenetic alopecia (AGA), the preeminent form of clinical hair loss, poses a significant challenge to patients. Growth factors (GFs) have been investigated for the treatment of hair loss. However, the issue of their optimal intra-dermal delivery remains a formidable obstacle. Type XVII collagen (COL17), which plays a crucial role in regulating the hair follicle aging process, has emerged as a highly promising candidate for hair loss treatment. Considering these constraints, we developed an IGF-1 loaded borate-modified rhCOL17 MN platform (I-mCOL17 MNs) for the treatment of AGA. The mCOL17 MNs are engineered to precisely control the release of bioactive payloads in response to dynamic changes in the microenvironment. A comprehensive investigation was conducted to verify the physicochemical characteristics, as well as the in vitro and in vivo biological activities of the MNs. Our findings demonstrate that, when contrasted with the clinically utilized drug minoxidil, our MN exhibits a remarkable capacity to enhance neovascularization, alleviate tissue-based inflammatory responses, and promote hair regeneration in murine models of AGA. Overall, this MN represents a novel, safer, and more efficient strategy for the treatment of AGA, offering new hope for patients suffering from this prevalent condition.

The review of nasal drug delivery system: The strategies to enhance the efficiency of intranasal drug delivery by improving drug absorption

Nasal drug administration constitutes an efficient and non-invasive modality of drug delivery, and its distinctive physiological structure offers potentialities for treating a variety of diseases. To elevate the drug absorption and delivery efficiency, it is of paramount importance to delineate the transport routes and their enhancement mechanisms. Nevertheless, drug absorption pathways vary depending on the disease target, these variations present opportunities for targeted delivery and challenges for achieving precision. Hence, this review outlines the anatomical structure of the nasal cavity, and subsequently elaborates on the drug transport pathways within the nasal cavity and their influencing factors. Based on the distinct sites of drug action, diseases suitable for nasal drug administration are categorized into three types: systemic diseases, local nasal diseases, and central nervous system diseases. Grounded on multiple transport routes and their influencing factors, this review proposes strategies like optimizing formulation viscosity, using penetration enhancers, adding mucosal adhesives and improving delivery device, offering insights into future advancements in nasal drug delivery systems.

Therapeutic potential of cell-permeable PEP-1-Srxn1 in mitigating oxidative and ischemic damage in the hippocampus

In the present study, we validated the neuroprotective effects of sulfiredoxin 1 (Srxn1) against oxidative damage in HT22 cells and ischemic damage in gerbil hippocampus. To efficiently deliver Srxn1 protein into cells or the hippocampus, a PEP-1-Srxn1 fusion protein was synthesized, and efficient delivery was visualized in HT22 mouse hippocampal neuronal cells. PEP-1-Srxn1 was delivered to HT22 cells in a concentration- and incubation time-dependent manner and showed significantly higher levels at 36 h after incubation for 1 h. Morphologically, the delivered protein was localized in the cytoplasm of HT22 cells. In addition, PEP-1-Srxn1 treatment significantly ameliorated formation of reactive oxygen species, DNA fragmentation, and cell death in HT22 cells induced by treatment with 100 μM H2O2. In gerbils, PEP-1-Srxn1 treatment significantly alleviated transient ischemia-induced forebrain hyperactivity 1 d after ischemia and memory deficits 4 d after ischemia. Neuroprotective effects were confirmed by morphological analysis of the hippocampal CA1 region 4 or 10 d after ischemia. Treatment with PEP-1-Srxn1 significantly ameliorated the formation of reactive oxygen species and lipid peroxidation in the hippocampus during the early stages (3-12 h) of ischemia. In addition, treatment with PEP-1-Srxn1 alleviated the ischemia-induced reduction of glutathione levels in the hippocampus. PEP-1-Srxn1 also decreased ischemia-induced microglial activation and pro-inflammatory cytokine release in the hippocampus. These results suggest that PEP-1-Srxn1 is a potential therapeutic agent for reducing neuronal damage induced by oxidative or ischemic damage.

SFXN1 Reduction Alleviates Cerebral Ischemia-Reperfusion Injury by Promoting Neuronal Survival and Reducing Neuroinflammation

AIM

Sideroflexin 1 (SFXN1) is an important inner mitochondrial membrane protein that regulates many physiological and pathological events. However, the role of SFXN1 in cerebral ischemia-reperfusion (I/R)-induced neuronal death remains unclear.

METHODS

We employed in vivo injury models of transient middle cerebral artery occlusion (tMCAO) and in vitro models of lipopolysaccharide (LPS) stimulation and oxygen-glucose deprivation/reperfusion (OGD/R) to investigate the regulatory effects of SFXN1 on neuroinflammation and brain injury. Western blotting, immunofluorescence, and real-time quantitative PCR were utilized to assess SFXN1 expression, proinflammatory signaling pathways activation, and cytokine levels in vitro. Cerebral infarction was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining and Nissl staining.

RESULTS

SFXN1 expression was upregulated following cerebral I/R injury. Both neurons and microglia exhibited increased SFXN1 expression after oxygen-glucose deprivation/reoxygenation (OGD/R) treatment. SFXN1 knockdown reduced OGD/R-induced neuronal death and alleviated cerebral I/R injury. Additionally, conditioned medium from SFXN1-knockdown microglia reduced neurotoxicity in vitro. Mechanistically, SFXN1 induced mitochondrial dysfunction and neuronal death after OGD/R in an iron-independent manner. Furthermore, SFXN1 promoted the production of proinflammatory cytokines by promoting NF-κB activation, partially through iron transport in microglia after OGD/R.

CONCLUSION

This study reveals the novel role of SFXN1 in exacerbating cerebral I/R injury by reducing neuronal survival through the modulation of mitochondrial function and promotion of microglia-mediated neuroinflammation via NF-κB activation.

Kirenol alleviates cerebral ischemia-reperfusion injury by reducing oxidative stress and ameliorating mitochondrial dysfunction via activating the CK2/AKT pathway

Ischemic stroke represents a predominant cause of morbidity and mortality globally, resulting from abrupt vascular occlusion or rupture, which precipitates considerable neuronal damage. This study aims to shed more light on the specific neuroprotective mechanisms of Kirenol, a bioactive diterpene derived from traditional herbal medicine, with a particular focus on its regulation of mitochondrial dynamics via the CK2/AKT signalling pathway and its impact on the mitochondrial fusion protein Optic atrophy 1 (Opa1). The effects of Kirenol on neuronal viability, mitochondrial function, and pertinent signalling pathways were evaluated by employing a middle cerebral artery occlusion (MCAO) model in rats and subjecting HT22 neuronal cells to oxidative stress. Treatment with Kirenol significantly improved neurological outcomes, augmented Opa1 expression, and restored apoptotic-related protein markers, antioxidative factors, mitochondrial membrane potential, and adenosine triphosphate (ATP) levels (P < 0.01). Mechanistically, Kirenol elevated CK2 levels and phosphorylated AKT while inhibiting CK2/AKT signalling attenuated Kirenol's protective effects on Opa1 expression. Furthermore, silencing Opa1 using siRNA diminished the neuroprotective effects of Kirenol on oxidative stress and apoptosis-related markers, underscoring the critical role of Opa1. In vitro assessments demonstrated that Kirenol effectively mitigated oxidative stress-induced neuronal damage, restoring cell morphology and viability. Kirenol exhibited dose-dependent neuroprotective effects in the MCAO model (P < 0.01). These findings elucidate the neuroprotective role of Kirenol in ischemic stroke through Opa1-mediated mitochondrial fusion and highlight the CK2/AKT pathway as a promising therapeutic target.

Brain Targeting Bacterial Extracellular Vesicles Enhance Ischemic Stroke Therapy via Efficient ROS Elimination and Suppression of Immune Infiltration

Ischemic stroke (IS) as a detrimental neurological disease is accompanied by oxidative-stress-induced injury, concurrent inflammatory response, overactivated brain immune microenvironment, and disruption of the blood-brain barrier (BBB). This cascade of events ultimately leads to neuronal death and significantly impairs the recovery of neurological function. In this study, we presented extracellular vesicles derived from the gut probiotic Lactobacillus reuteri (LrEVs) integrated with brain targeting, reactive oxygen species (ROS) scavenging, and reduced infiltration of immune cells for effective multiple therapeutic interventions of IS. LrEVs inherited peptidoglycan (PGN) specifically targeted upregulated toll-like receptor 2 (TLR2) in the injured region of the ischemic brain, achieving the effective penetration of the BBB and accumulation in the ischemic brain. In the meantime, LrEVs prevented neuronal apoptosis after stroke by scavenging ROS overproduction and modulating microglial polarization through inhibition of the MAPK and NF-κB pathways. Furthermore, LrEVs inhibited the aggregation of C-C motif chemokine ligand 2 (CCL2), reduced the infiltration of peripheral immune cells such as macrophages and neutrophils into ischemic brain tissue, and suppressed the impairment of BBB, thereby improving the overactivated brain immune microenvironment. The findings provide a vesicle that combines ROS scavenging and modulation of the immune microenvironment, showcasing the potential of gut-probiotic-derived vesicles to treat neurological damage.

Applications of Matrix Metalloproteinase-9-Related Nanomedicines in Tumors and Vascular Diseases

Matrix metalloproteinase-9 (MMP-9) is implicated in tumor progression and vascular diseases, contributing to angiogenesis, metastasis, and extracellular matrix degradation. This review comprehensively examines the relationship between MMP-9 and these pathologies, exploring the underlying molecular mechanisms and signaling pathways involved. Specifically, we discuss the contribution of MMP-9 to tumor epithelial-mesenchymal transition, angiogenesis, and metastasis, as well as its involvement in a spectrum of vascular diseases, including macrovascular, cerebrovascular, and ocular vascular diseases. This review focuses on recent advances in MMP-9-targeted nanomedicine strategies, highlighting the design and application of responsive nanoparticles for enhanced drug delivery. These nanotherapeutic strategies leverage MMP-9 overexpression to achieve targeted drug release, improved tumor penetration, and reduced systemic toxicity. We explore various nanoparticle platforms, such as liposomes and polymer nanoparticles, and discuss their mechanisms of action, including degradation, drug release, and targeting specificity. Finally, we address the challenges posed by the heterogeneity of MMP-9 expression and their implications for personalized therapies. Ultimately, this review underscores the diagnostic and therapeutic potential of MMP-9-targeted nanomedicines against tumors and vascular diseases.

Microenvironment-adaptive nanomedicine MXene promotes flap survival by inhibiting ROS cascade and endothelial pyroptosis

In the field of large-area trauma flap transplantation, preventing avascular necrosis remains a critical challenge. Key mechanisms for improving flap viability include angiogenesis promotion, oxidative stress inhibition, and cell death prevention. Recently, two-dimensional ultrathin Ti3C2TX (MXene) nanosheets have gained attention for their potential contributions to these processes, though MXene's physiological impact on flap survival had not been previously investigated. This study is the first to confirm MXene's biological effects on the ischaemic microenvironment post-skin flap transplantation. Findings indicated that MXene significantly decreased the necrotic area in ischaemic flaps (37.96% ± 2.00%), with reductions of 30.40% ± 1.86% at 1 mg/mL and 20.19% ± 2.11% at 2 mg/mL in a concentration-dependent manner. Mechanistically, MXene facilitated in situ angiogenesis, mitigated oxidative stress, suppressed pro-inflammatory pyroptosis, and activated the PI3K-Akt pathway, particularly influencing vascular endothelial cells. Comparative transcriptome analysis of skin tissues with and without MXene treatment provided additional evidence, highlighting mechanisms such as pro-inflammatory pyroptosis, ROS metabolic processes, endothelial cell proliferation regulation, and PI3K-Akt signaling pathway activation. Overall, MXene demonstrated biological activity, effectively promoting ischaemic flaps survival and presenting a novel strategy for addressing ischaemic necrosis in skin flaps.

Clusterzyme-Enabled Oxidative Stress Alleviation and Microglial Polarization Modulation for Efficient Ischemic Stroke Treatment

Ischemic stroke (IS) presents a significant challenge to global health, as conventional reperfusion strategies aimed at restoring cerebral circulation paradoxically exacerbate neurological damage. This injury primarily results from the excessive production of reactive oxygen species (ROS) and the initiation of a widespread neuroinflammatory response. In this study, mercaptosuccinic acid (MSA)-coated bimetallic clusterzymes, containing an optimized ratio of Au7Ag1 nanoclusters (NCs), are developed for the targeted treatment of IS reperfusion injury. The ultrafine particle size of bimetallic nanoclusters facilitates the penetration across the blood-brain barrier (BBB) and enhances catalytic capacity and enzymatic activity through synergistic effects. Comprehensive in vitro and in vivo studies demonstrate that Au7Ag1 NCs provide neuroprotection by efficiently scavenging ROS and modulating microglial polarization, alleviating oxidative stress-induced injury. Furthermore, Au7Ag1 NCs play a crucial role in reducing brain tissue damage following reperfusion and promoting long-term neurological function recovery. Notably, RNA sequencing reveals that Au7Ag1 NCs impact key molecular pathways linked to apoptosis and inflammation. In summary, this study demonstrates the potential of Au7Ag1 NCs as a novel therapeutic approach for IS reperfusion injury and highlights a promising pathway for nanomedicine-based interventions targeting ischemic cerebral disorders.

Irisin protects against cerebral ischemia reperfusion injury in a SIRT3-dependent manner

Background

Cerebral ischemia-reperfusion (CIR) injury critically impacts stroke prognosis, yet effective therapeutic strategies remain limited. Irisin, an exercise-induced myokine, exhibits neuroprotective effects against cerebral ischemia. SIRT3, a mitochondrial deacetylase, is similarly implicated in mitigating ischemia-reperfusion injury. Given that irisin exerts protection via AMPK/PGC-1α pathway activation and SIRT3 acts downstream of PGC-1α , we hypothesized that SIRT3 mediates irisin's neuroprotection in CIR injury.

Methods

In vivo cerebral ischemia-reperfusion injury was modeled by inducing transient middle cerebral artery occlusion (MCAO) in mice, while in vitro CIR conditions were replicated using oxygen-glucose deprivation (OGD) in PC12 neuronal cultures. To elucidate the mechanistic role of SIRT3, targeted interventions were implemented: SIRT3 expression was silenced via transfection with small interfering RNA (siRNA), and its enzymatic activity was pharmacologically inhibited using 3-TYP, a selective SIRT3 inhibitor. Apoptotic were systematically evaluated through TUNEL staining, Western blot analysis of caspase-3, Bax and Bcl-2. Oxidative stress parameters, including malondialdehyde (MDA) levels and glutathione (GSH) content, were measured using colorimetric assays. Neurological function in mice was quantified using the modified Neurological Severity Score (mNSS).

Results

Our results demonstrated that irisin mitigates apoptosis and oxidative stress by dose-dependently activating SIRT3 signaling. At the optimal dosage, irisin effectively restored SIRT3 expression levels, reduced neuronal damage, and improved neurological recovery in CIR injury models. Notably, the therapeutic effects of irisin were significantly attenuated by 3-TYP, a specific SIRT3 inhibitor. Further validation through in vitro experiments revealed that SIRT3 overexpression synergistically enhanced irisin-mediated protection against OGD-induced injury, whereas SIRT3 knockout substantially diminished its efficacy.

Conclusion

Our data shown that irisin exerted a protective role in CIR injury, at least in part, through SIRT3 activation. This study establishes the irisin/SIRT3 as a novel therapeutic target for ischemic stroke, providing mechanistic insights for future interventions.

Anti-Inflammatory Combination of Puerarin and Ac2-26 Using Intranasal Delivery for Effective Against Ischemic Stroke in Rat Model

Purpose

The pathological mechanisms underlying ischemic stroke are highly complex, with the neuroinflammatory response triggered by cerebral ischemia-reperfusion being a major contributor to secondary brain damage. This response significantly impedes neural tissue regeneration. Despite advancements in treatment, current anti-inflammatory strategies remain suboptimal in terms of safety and efficacy. This study aimed to develop an all-natural nanomedicine delivery system for the transnasal administration of puerarin, combined with the endogenous anti-inflammatory peptide Ac2-26, to enhance neuroprotection against ischemic stroke through a synergistic anti-inflammatory approach.

Methods

In this study, collagen nanoparticles (PueNps) loaded with puerarin were synthesized, followed by the preparation of a chitosan hydrogel. The PueNps and Ac2-26 were co-encapsulated within the hydrogel, resulting in the formation of the PueNps&Ac2-26 gel formulation. The physicochemical properties of this formulation, as well as its biodistribution and anti-ischemic efficacy in the MCAO rat brain, were evaluated.

Results

In this formulation system, the bioavailability of puerarin and Ac2-26 was enhanced, exhibiting sustained-release properties, which enabled efficient brain-targeted delivery. It effectively alleviated neurological impairment in MCAO rats, reduced the volume of cerebral infarction, and decreased brain water content. Additionally, the PueNps&Ac2-26 gel significantly inhibited neuroinflammation in rats and alleviated oxidative stress.

Conclusion

The PueNps&Ac2-26 gel is a purely natural and efficient formulation system, offering a promising approach for the clinical treatment of ischemic stroke in the future.

Injectable hydrogels with ROS-triggered drug release enable the co-delivery of antibacterial agent and anti-inflammatory nanoparticle for periodontitis treatment

Periodontitis, a chronic inflammatory disease caused by bacteria, is characterized by localized reactive oxygen species (ROS) accumulation, leading to an inflammatory response, which in turn leads to the destruction of periodontal supporting tissues. Therefore, antibacterial, scavenging ROS, reducing the inflammatory response, regulating periodontal microenvironment, and alleviating alveolar bone resorption are effective methods to treat periodontitis. In this study, we developed a ROS-responsive injectable hydrogel by modifying hyaluronic acid with 3-amino phenylboronic acid (PBA) and reacting it with poly(vinyl alcohol) (PVA) to form a borate bond. In addition, the ROS-responsive hydrogel encapsulated the antibacterial agent minocycline hydrochloride (MH) and Fe-Quercetin anti-inflammatory nanoparticles (Fe-Que NPs) for on-demand drug release in response to the periodontitis microenvironment. This hydrogel (HP-PVA@MH/Fe-Que) exhibited highly effective antibacterial properties. Moreover, by modulating the Nrf2/NF-κB pathway, it effectively eliminated ROS and promoted macrophage polarization to the M2 phenotype, reducing inflammation and enhancing the osteogenic differentiation potential of human periodontal ligament stem cells (hPDLSCs) in the periodontal microenvironment. Animal studies showed that HP-PVA@MH/Fe-Que significantly reduced alveolar bone loss and enhanced osteogenic factor expression by killing bacteria and inhibiting inflammation. Thus, HP-PVA@MH/Fe-Que hydrogel had efficient antibacterial, ROS-scavenging, anti-inflammatory, and alveolar bone resorption-alleviation abilities, showing excellent application potential for periodontitis healing.

Neurological Emergency Treatment Strategy: A Neuron-Targeted Regulation System for Reactive Oxygen Species Metabolism through Ferroptosis Modulation

Spinal cord injury (SCI) represents a significant clinical challenge. Following SCI, the implementation of protective measures for neurons is critically important. Current clinical applications of hormone pulse therapy exhibit variable efficacy and considerable side effects, highlighting an urgent need for therapeutic strategies. This study investigates the pathological conditions of ischemia and hypoxia in the SCI region, complemented by early transcriptome sequencing postinjury. Our findings suggest that targeting ferroptosis is pivotal for early neuroprotection following SCI. Aiming at the cascade effect of mitochondrial damage leading to reactive oxygen species (ROS) production, along with extensive ROS-mediated lysosomal damage during ferroptosis signaling, we developed a liposome-based system for regulating iron metabolism─DTLS@CAT. This innovative liposome is designed to specifically target neuronal mitochondria, effectively eliminate mitoROS, and modulate complex interactions among iron metabolism, mitochondria, lysosomes, and ROS to facilitate recovery from SCI.

Metabolic reprogramming and astrocytes polarization following ischemic stroke

Astrocytes are critical for maintaining neuronal activity. Activation of astrocytes, occurs within minutes from ischemic stroke onset due to ischemic causes and subsequent inflammatory damage. Activated astrocytes, also known as reactive astrocytes, are divided into two different phenotypes: A1 (pro-inflammatory) and A2 (anti-inflammatory) astrocytes. A2 astrocytes support neuronal survival and promote tissue healing, while A1 astrocytes have neurotoxic effects. Thus, polarization of reactive astrocyte into A1 or A2 genotype is closely correlated with the development of cerebral ischemia/reperfusion (I/R) injury. Metabolic reprogramming is a process that various metabolic pathways upregulate in cells to balance energy, alter their phenotype, and produce building-block requirements. A1 and A2 astrocytes display different metabolic reprogramming, such as glycolysis, glutamate uptake, and glycogenolysis. Accumulating evidence suggested that manipulation of energy metabolism homeostasis can induce astrocytes to switch from A1 to A2 phenotype. This review disucss the potential factors in affecting astrocytic polarization, emphasizes metabolic reprogramming in reactive astrocytes within the pathophysiological context of cerebral I/R, and explores the relationship between metabolic reprogramming and astrocytic polarization. Importantly, we reveal that regulating metabolic reprogramming in reactive astrocytes may be a potential therapeutic target for cerebral I/R injury.

NO-releasing double-crosslinked responsive hydrogels accelerate the treatment and repair of ischemic stroke

Stroke is a global disease that seriously threatens human life. The pathological mechanisms of ischemic stroke include neuroinflammation, oxidative stress, and the destruction of blood vessels at the lesion site. Here, a biocompatible in situ hydrogel platform was designed to target multiple pathogenic mechanisms post-stroke, including anti-inflammation, anti-oxidant, and promotion of angiogenesis. Double-crosslinked responsive multifunctional hydrogels could quickly respond to the pathological microenvironment of the ischemic damage site and mediate the delivery of nitric oxide (NO) and ISO-1 (inhibitor of macrophage migration inhibitory factor, MIF). The hydrogel demonstrated good biocompatibility and could scavenge reactive oxygen species (ROS) and inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-10 (IL-10), and MIF. In a mouse stroke model, hydrogels, when situated within the microenvironment of cerebral infarction characterized by weak acidity and elevated ROS release, would release anti-inflammatory nanoparticles rapidly that exert an anti-inflammatory effect. Concurrently, NO was sustained release to facilitate angiogenesis and provide neuroprotective effects. Neurological function was significantly improved in treated mice as assessed by the modified neurological severity score, rotarod test, and open field test. These findings indicate that the designed hydrogel held promise for sustained delivery of NO and ISO-1 to alleviate cerebral ischemic injury by responding to the brain's pathological microenvironment.

Versatile carrier-free binary nanodrug based on metformin/epigallocatechin gallate nanoparticles: exploring its properties and potential in cancer treatment

Epigallocatechin gallate (EGCG), an important active component extracted from green tea, has attracted much attention due to its multiple biological activities such as antioxidant, antibacterial, anti-inflammatory, and antitumor effects. Meanwhile, metformin (Met), a classic drug for the treatment of type 2 diabetes, exhibits additional benefits such as hypoglycemic, antioxidant, anti-inflammatory, and antitumor effects. However, metformin often causes gastrointestinal reactions when used alone, affecting patients' quality of life. In view of this, we proposed an innovative technique for the fabrication of a carrier-free, dual-loaded nanodrug, Met-EGCG nanoparticles (Met-EGCG NPs), via self-assembly. The method for preparing Met-EGCG NPs is simple, rapid and cost-effective. In addition, the carrier-free Met-EGCG NPs nanodrug inherits the strong antioxidant capacity, good biocompatibility and excellent aggregation-induced fluorescence effect of EGCG, and even offer significant advantages in enhancing drug solubility, stability, and bioavailability, while effectively reducing the occurrence of side effects. Moreover, this Met-EGCG NPs nanodrug exhibits a synergistic therapeutic effect of EGCG and metformin, thereby significantly enhancing overall therapeutic efficacy, and demonstrates excellent potential in anti-cancer applications. This study not only successfully prepared Met-EGCG NPs but also experimentally verified their superior performance, opening a new path for the application of EGCG in drug therapy. This carrier-free, dual-loaded drug delivery nanosystem based on Met-EGCG NPs offers potential for drug combination therapy, promising to play a more critical role in the biomedical field and providing new insights and guidance for the development of future multidrug delivery systems.

ROS-responsive quercetin-based polydopamine nanoparticles for targeting ischemic stroke by attenuating oxidative stress and neuroinflammation

Ischemic stroke (IS), a prevalent cerebrovascular disorder, is characterized by high morbidity rates and significant disability. However, relevant drug therapy for IS still suffers from limitations such as limited blood-brain barrier (BBB) penetration efficiency, single therapeutic target, short half-life, and strong side effects. The development of multi-target neuroprotective agents using natural drug molecules with low toxicity and combining them with nanotechnology to improve BBB permeability and drug utilization is an important direction in the development of IS therapeutic strategies. Based on the anti-inflammatory and antioxidant properties of quercetin (Que), as well as the ROS-responsive degradation properties of polydopamine (PDA), an IS therapeutic strategy (Que@DAR NPs) was developed in this study. Que@DAR NPs were formed by dopamine wrapping Que by oxidative self-assembly and wrapping the rabies virus glycoprotein (RVG29) on the surface. The results showed that Que@DAR NPs greatly improved the dispersion stability of Que and exhibited ROS-responsive degradation properties. Cellular internalization assay in human neuroblastoma cells (SH-SY5Y) showed that RVG29 peptide substantially augmented the cellular uptake of Que@DAR NPs. Moreover, Que@DAR NPs can effectively reduce the oxidative damage of SH-SY5Y cells and induce the polarization of microglia to anti-inflammatory (M2) phenotype. In vivo studies further demonstrated that Que@DAR NPs inhibited neuroinflammation, reduced neuronal apoptosis, and significantly ameliorated neurological dysfunction in a rat model of middle cerebral artery occlusion (MCAO). In conclusion, Que@DAR NPs provide a safe and effective new strategy for the precision treatment of IS.

Mitochondrial transfer of drug-loaded artificial mitochondria for enhanced anti-Glioma therapy through synergistic apoptosis/ferroptosis/immunogenic cell death

Mitochondrial targeting in gliomas represents a novel therapeutic strategy with significant potential to enhance drug sensitivity by effectively killing glioma cells at the mitochondrial level. In this study, we developed artificial mitochondria derived from mitochondrial membrane-based nanovesicles, enabling precise mitochondrial targeting of doxorubicin (Dox) to selectively eradicate cancer cells by amplifying multiple cell death pathways. It was found that Dox-encapsulating mitochondria-based nanovesicles (DOX-MitoNVs) exhibited an extraordinary ability to penetrate the blood-brain barrier (BBB), specifically targeting gliomas. By targeting mitochondria instead of locating at the nucleus, DOX-MitoNVs not only amplified Dox mediated apoptosis effects through the overloading of intracellular Ca2+ but also intensified ferroptosis by generating reactive oxygen species (ROS). Furthermore, DOX-MitoNVs demonstrated a significant ability to modulate the tumor immune microenvironment, thereby inducing pronounced immunogenic cell death (ICD) effects. In summary, it presents a novel therapeutic strategy utilizing DOX-MitoNVs for precise mitochondrial targeting in gliomas, enhancing drug sensitivity, inducing multiple cell death pathways, and modulating the tumor immune microenvironment to promote immunogenic cell death. STATEMENT OF SIGNIFICANCE: Mitochondrial targeting in gliomas is a promising therapeutic strategy that enhances drug sensitivity by exploiting glioma cells' mitochondrial vulnerabilities. We engineered mitochondrial membrane-based nanovesicles as artificial mitochondria for precise mitochondrial targeting of Dox. This approach facilitates selective cancer cell eradication and amplifies multiple cell death pathways alongside immunogenic chemotherapy. Notably, DOX-MitoNVs effectively cross the BBB and specifically target gliomas. By focusing on mitochondria, Dox induces apoptosis and intensifies ferroptosis through ROS generation. Additionally, DOX-MitoNVs can transform the tumor immune microenvironment, promoting ICD. Overall, DOX-MitoNVs offer a promising platform for enhanced glioma therapy.

Pink1/Parkin signaling mediates pineal mitochondrial autophagy dysfunction and its biological role in a comorbid rat model of depression and insomnia

Using a chronic unpredictable mild stress (CUMS) combined with multi-platform water environment sleep deprivation (SD) as an animal model, the occurrence and development of human depression combined with insomnia were simulated. The abnormal mitochondrial autophagy signaling caused by the putative kinase 1/Parkin E3 ubiquitin protein ligase (Pink1/Parkin) signaling pathway directly affects the normal secretion of melatonin by the pineal gland, which may explain the pathogenesis of depression combined with insomnia. This study aims to explore the depression-like behavior, sleep changes, central oxidative stress response, pineal mitochondrial autophagy damage, melatonin secretion, histopathological changes of the pineal gland, and the expression of Pink1/Parkin signaling-related factors in CUMS+SD rats. The results showed that the levels of reactive oxygen species (ROS) in cerebrospinal fluid of CUMS+SD rats significantly increased along with the inflammatory factors Interleukin-1β (IL-1β) and nuclear factor kappa-B (NF-κB) in cerebrospinal fluid. In addition, the number of pineal gland cells significantly decreased, cell boundaries became blurred, cell volume shrank, and apoptotic bodies appeared in the pineal gland tissue under HE staining, indicating pineal gland inflammation. Sleep deprivation further disrupted the levels of autophagy damage factors, including histamine (MDA), glutathione (GSH), and catalase (CAT), in the cerebrospinal fluid of CUMS+ SD rats. Transmission electron microscopy of the pineal gland in CUMS+SD rats revealed damage to mitochondrial autophagy. The levels of 5-hydroxytryptamine (5-HT) and aromatic amine-N-acetyltransferase (AANAT) in the cerebrospinal fluid, as well as melatonin levels in the pineal gland, were significantly decreased. Additionally, the expression of IL-1β, NF-κB, Pink1, and Parkin in the pineal gland of CUMS+SD rats significantly increased. The expression of microtubule-associated protein 1 light chain 3-β (LC3), selective autophagy adaptor protein (P62), cytochrome c oxidase IV (COXIV), and mitochondrial outer membrane translocation enzyme 20 (TOM20) proteins downstream of the Pink1/Parkin signaling pathway was enhanced, while the expression of downstream brain-derived neurotrophic factor (BDNF), Beclin 1, and BCL2 interacting protein 3 (BNIP3) proteins was negatively regulated. Pink1/Parkin signaling may specifically respond to mitochondrial autophagy damage in the pineal gland, affecting the normal synthesis and secretion of melatonin in the pineal gland. In summary, mitochondrial autophagy damage in the pineal gland affects the normal secretion of melatonin in CUMS+SD rats, which is closely related to the specific autophagy signaling impairment of Pink1/Parkin pathway, which may mediate the occurrence of depression combined with insomnia.

Nasal administration of Xingnaojing biomimetic nanoparticles for the treatment of ischemic stroke

Xingnaojing injection (XNJ), is the first-line Chinese medicine injection approved for treating ischemic stroke (IS). XNJ can attenuate the inflammatory responses and oxidative stress, thus reversing neuronal damage of IS. This study aims to prepare the biomimetic nanoparticles (Bo-GEVs/XNJM) of nasal administration for IS treatment. The grapefruit extracellular vesicles (GEVs) loaded with microemulsions sourced from Xingnaojing injection (XNJM) are modified with borneol (Bo) to bypass the blood-brain barrier (BBB). Bo-GEVs/XNJM has the property of brain-targeting, and in vivo and in vitro experiments have validated that it has positive effects in reducing apoptosis, inhibiting oxidative stress, anti-inflammation, protecting mitochondrial function, and protecting the BBB. In summary, Bo-GEVs/XNJM has good neuroprotective effects, and provides an interventional method for the treatment of ischemic stroke.

Inhibiting Mitochondrial Damage for Efficient Treatment of Cerebral Ischemia-Reperfusion Injury Through Sequential Targeting Nanomedicine of Neuronal Mitochondria in Affected Brain Tissue

Oxidative stress, predominantly from neuronal mitochondrial damage and the resultant cytokine storm, is central to cerebral ischemia-reperfusion injury (CIRI). However, delivering drugs to neuronal mitochondria remains challenging due to the blood-brain barrier (BBB), which impedes drug entry into affected brain tissues. This study introduces an innovative tannic acid (TA) and melanin-modified heteropolyacid nanomedicine (MHT), which highly specifically eliminates the neuronal mitochondrial reactive oxygen radicals burst to efficiently reduce neuronal mitochondrial damage through a strategically designed sequential targeting strategy from affected brain tissue to neuronal mitochondria. TA endows MHT with sequential targeting ability by binding to matrix proteins exposed to the damaged BBB and mitochondrial outer membrane proteins of neurons, while melanin significantly enhances the antioxidant capacity of MHT. Consequently, MHT effectively inhibits neuronal apoptosis by protecting mitochondria and reversing the inflammatory immune environment through the deactivation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. MHT demonstrated a strong therapeutic effect on CIRI, with an ultralow dose (2 mg kg-1) proving effective in reversing the condition. This work not only introduces a new avenue to significantly reduce CIRI through sequential targeting therapy but also offers a new paradigm for treating other ischemia-reperfusion injury diseases.

Gastrodin against oxidative stress-inflammation crosstalk via inhibiting mtDNA/TLR9 and JAK2/STAT3 signaling to ameliorate ischemic stroke injury

The pathway of Janus-activated kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) (termed as JAK2/STAT3) plays an active role in stroke-related inflammation induced by ischemic stress. Gastrodin, the primary compound in Gastrodia elata Bl, has been identified for its notable neuroprotective effects and demonstrated to ameliorate cerebral ischemia-reperfusion but its exact mechanisms governing this defense are still unclear. This study aims to investigate whether gastrodin can regulate mitochondrial function via the JAK2/STAT3 pathway to limit cerebral ischemia-reperfusion. In vivo, gastrodin significantly reduced infarct volume, improved neurobiological function, attenuated neuronal apoptosis, oxidative stress, mitochondrial impairment, mtDNA leakage, and inflammatory responses. At the cellular level, gastrodin administration rescued OGD/R-induced cell apoptosis, oxidative stress, and mitochondrial dysfunction. Mechanistically, gastrodin notably suppressed Toll-like receptor 9 (TLR9) expression, important for the recognition of disrupted endogenous DNA to produce inflammatory reactions. Furthermore, gastrodin mitigated inflammation by inhibiting JAK2/STAT3 signaling, influencing inflammatory factors to aggravate inflammation. Notably, the effects of gastrodin were abolished by Coumermycin A1 (C-A1), a JAK2 agonist, validating the role of JAK2/STAT3 signaling. In summary, gastrodin enhances the protective effect against mitochondrial damage in ischemic stroke by inhibiting JAK2/STAT3 signaling. Gastrodin is a possible therapy for cerebral ischemia.

An Update on Recent Drug Delivery Systems Targeting Brain Diseases via the Transnasal Pathway

OBJECTIVE

To explore the potential of transnasal drug delivery systems (DDS) as an effective means of bypassing the bloodbrain barrier (BBB) for enhanced central nervous system (CNS) targeting, aiming to improve therapeutic outcomes for CNS disorders while reducing systemic side effects.

METHODS

A review of current and emerging DDS technologies, including polymer nanoparticles, liposomes, and micelles, was conducted to assess their suitability for precision-targeted delivery to the brain through the transnasal route.

RESULTS

The investigated DDS demonstrate promising capabilities for CNS targeting via the nasal pathway, effectively preserving both the nasal mucosa and CNS integrity. These systems enhance drug precision within neural tissues, potentially improving therapeutic outcomes without harming adjacent tissues.

CONCLUSIONS

Transnasal DDS offer a promising alternative to traditional delivery methods, with significant potential to advance the treatment of cerebrovascular diseases, neurodegenerative disorders, brain tumors, and psychiatric conditions. This approach represents an evolving frontier in neurotherapeutics, with the potential to transform CNS drug delivery practices.

Advancements in mitochondrial-targeted nanotherapeutics: overcoming biological obstacles and optimizing drug delivery

In recent decades, nanotechnology has significantly advanced drug delivery systems, particularly in targeting subcellular organelles, thus opening new avenues for disease treatment. Mitochondria, critical for cellular energy and health, when dysfunctional, contribute to cancer, neurodegenerative diseases, and metabolic disorders. This has propelled the development of nanomedicines aimed at precise mitochondrial targeting to modulate their function, marking a research hotspot. This review delves into the recent advancements in mitochondrial-targeted nanotherapeutics, with a comprehensive focus on targeting strategies, nanocarrier designs, and their therapeutic applications. It emphasizes nanotechnology's role in enhancing drug delivery by overcoming biological barriers and optimizing drug design for specific mitochondrial targeting. Strategies exploiting mitochondrial membrane potential differences and specific targeting ligands improve the delivery and mitochondrial accumulation of nanomedicines. The use of diverse nanocarriers, including liposomes, polymer nanoparticles, and inorganic nanoparticles, tailored for effective mitochondrial targeting, shows promise in anti-tumor and neurodegenerative treatments. The review addresses the challenges and future directions in mitochondrial targeting nanotherapy, highlighting the need for precision, reduced toxicity, and clinical validation. Mitochondrial targeting nanotherapy stands at the forefront of therapeutic strategies, offering innovative treatment perspectives. Ongoing innovation and research are crucial for developing more precise and effective treatment modalities.

Microenvironment-responsive nanosystems for ischemic stroke therapy

Ischemic stroke, a common neurological disorder caused by impaired blood supply to the brain, presents a therapeutic challenge. Conventional treatments like thrombolysis and neuroprotection drugs lack ideal drug delivery systems, limiting their effectiveness. Selectively delivering therapies to the ischemic cerebral tissue holds great potential for preventing and/or treating ischemia-related pathological symptoms. The unique pathological microenvironment of the brain after ischemic stroke, characterized by hypoxia, acidity, and inflammation, offers new possibilities for targeted drug delivery. Pathological microenvironment-responsive nanosystems, extensively investigated in tumors with hypoxia-responsive systems as an example, could also respond to the ischemic cerebral microenvironment and achieve brain-targeted drug delivery and release. These emerging nanosystems are gaining traction for ischemic stroke treatment. In this review, we expound on the cerebral pathological microenvironment and clinical treatment strategies of ischemic stroke, highlight various stimulus-responsive materials employed in constructing ischemic stroke microenvironment-responsive nano delivery systems, and discuss the application of these microenvironment-responsive nanosystems in microenvironment regulation for ischemic stroke treatment.

Association between Life's simple 7 and post-stroke depression symptom from 2005-2016 NHANES survey: A cross-sectional study

BACKGROUND

Depression symptoms are a common complication of stroke and heart disease and is a predictor of Post-stroke depression (PSD). However, the relationship between overall cardiovascular health indicators and PSD remains unclear.

METHODS

Data were collected from stroke patients in the 2005-2016 National Health and Nutrition Examination Surveys (NHANES) survey. Depression was defined as a Patient Health Questionnaire-9 (PHQ-9) score ≥10. In addition, PSD was defined as the coexistence of stroke and depression. Life's Simple 7 (LS7) provides an assessment of cardiovascular health and consists of 7 items. The LS7 scores range from 0 to 14 and can also be categorized into poor (0-7), average (8-10), and ideal (11-14). Logistic regression models were used to investigate the relationship between LS7 and PSD.

RESULTS

The average age of participants was 64.2 years, with 45.1% and 34.3 % being male and non-Hispanic whites, respectively. After adjusting for age, sex, race, education, and income, the LS7 scores were found to be associated with reduced PSD odds (OR: 0.76, 95% CI: 0.68-0.85, P: <0.001), as well as the number of ideal LS7 metrics (OR: 0.69, 95% CI: 0.56-0.85, P: <0.001). Furthermore, non-poor LS7 was also associated with a lower risk of PSD compared to poor LS7 (OR: 0.48, 95% CI: 0.25-0.91, P: 0.01). This association was stable in stratification analyses.

CONCLUSION

Cardiovascular health status assessed by LS7 was negatively associated with PSD. Future studies are required to verify these findings.

Precise subcellular targeting approaches for organelle-related disorders

Pharmacological research has expanded to the nanoscale level with advanced imaging technologies, enabling the analysis of drug distribution at the cellular organelle level. These advances in research techniques have contributed to the targeting of cellular organelles to address the fundamental causes of diseases. Beyond navigating the hurdles of reaching lesion tissues upon administration and identifying target cells within these tissues, controlling drug accumulation at the organelle level is the most refined method of disease management. This approach opens new avenues for the development of more potent therapeutic strategies by delving into the intricate roles and interplay of cellular organelles. Thus, organelle-targeted approaches help overcome the limitations of conventional therapies by precisely regulating functionally compartmentalized spaces based on their environment. This review discusses the basic concepts of organelle targeting research and proposes strategies to target diseases arising from organelle dysfunction. We also address the current challenges faced by organelle targeting and explore future research directions.

Targeted pathophysiological treatment of ischemic stroke using nanoparticle-based drug delivery system

Ischemic stroke poses significant challenges in terms of mortality and disability rates globally. A key obstacle to the successful treatment of ischemic stroke lies in the limited efficacy of administering therapeutic agents. Leveraging the unique properties of nanoparticles for brain targeting and crossing the blood-brain barrier, researchers have engineered diverse nanoparticle-based drug delivery systems to improve the therapeutic outcomes of ischemic stroke. This review provides a concise overview of the pathophysiological mechanisms implicated in ischemic stroke, encompassing oxidative stress, glutamate excitotoxicity, neuroinflammation, and cell death, to elucidate potential targets for nanoparticle-based drug delivery systems. Furthermore, the review outlines the classification of nanoparticle-based drug delivery systems according to these distinct physiological processes. This categorization aids in identifying the attributes and commonalities of nanoparticles that target specific pathophysiological pathways in ischemic stroke, thereby facilitating the advancement of nanomedicine development. The review discusses the potential benefits and existing challenges associated with employing nanoparticles in the treatment of ischemic stroke, offering new perspectives on designing efficacious nanoparticles to enhance ischemic stroke treatment outcomes.

Intranasal delivery of imaging agents to the brain

The potential of intranasal administered imaging agents to altogether bypass the blood-brain barrier offers a promising non-invasive approach for delivery directly to the brain. This review provides a comprehensive analysis of the advancements and challenges of delivering neuroimaging agents to the brain by way of the intranasal route, focusing on the various imaging modalities and their applications in central nervous system diagnostics and therapeutics. The various imaging modalities provide distinct insights into the pharmacokinetics, biodistribution, and specific interactions of imaging agents within the brain, facilitated by the use of tailored tracers and contrast agents. Methods: A comprehensive literature search spanned PubMed, Scopus, Embase, and Web of Science, covering publications from 1989 to 2024 inclusive. Starting with advancements in tracer development, we going to explore the rationale for integration of imaging techniques, and the critical role novel formulations such as nanoparticles, nano- and micro-emulsions in enhancing imaging agent delivery and visualisation. Results: The review highlights the use of innovative formulations in improving intranasal administration of neuroimaging agents, showcasing their ability to navigate the complex anatomical and physiological barriers of the nose-to-brain pathway. Various imaging techniques, MRI, PET, SPECT, CT, FUS and OI, were evaluated for their effectiveness in tracking these agents. The findings indicate significant improvements in brain targeting efficiency, rapid uptake, and sustained brain presence using innovative formulations. Conclusion: Future directions involve the development of optimised tracers tailored for intranasal administration, the potential of multimodal imaging approaches, and the implications of these advancements for diagnosing and treating neurological disorders.

Bibliometric insights into the inflammation and mitochondrial stress in ischemic stroke

BACKGROUND

Research in the areas of inflammation and mitochondrial stress in ischemic stroke is rapidly expanding, but a comprehensive overview that integrates bibliometric trends with an in-depth review of molecular mechanisms is lacking.

OBJECTIVE

To map the evolving landscape of research using bibliometric analysis and to detail the molecular mechanisms that underpin these trends, emphasizing their implications in ischemic stroke.

METHODS

We conducted a bibliometric analysis to identify key trends, top contributors, and focal research themes. In addition, we review recent research advances in mitochondrial stress and inflammation in ischemic stroke to gain a detailed understanding of the pathophysiological processes involved.

CONCLUSION

Our integrative approach not only highlights the growing research interest and collaborations but also provides a detailed exploration of the molecular mechanisms that are central to the pathology of ischemic stroke. This synthesis offers valuable insights for researchers and paves the way for targeted therapeutic interventions.

Albumin-Based MUC13 Peptide Nanomedicine Suppresses Liver Cancer Stem Cells via JNK-ERK Signaling Pathway-Mediated Autophagy Inhibition

Targeting liver cancer stem cells (LCSCs) is a promising strategy for hepatocellular carcinoma (HCC) therapy. Target selection and corresponding inhibitor screening are of vital importance for eliminating the stemness of LCSCs. Peptide-based agents are hopeful but have long been hindered for in vivo application. Herein, we selected a clinically significant target MUC13 and screened out a suitable peptide for preparation of an albumin-based MUC13 peptide nanomedicine, P3@HSA, which suppressed liver cancer stem cells via JNK-ERK signaling pathway-mediated autophagy inhibition. The selected target MUC13 was highly expressed in LCSCs and associated with the prognosis of liver cancer patients. Encouraged by this observation, we screened the corresponding peptide-based inhibitor P3 for further evaluation. P3 could interact with albumin through the intrinsic hydrophobic force and formed the nanomedicine P3@HSA. The prepared nanomedicine could inhibit LCSCs through JNK-ERK signaling pathway-mediated autophagy inhibition and exert potent antitumor effect both in vitro and in vivo. Together, this study provides a promising peptide-based nanomedicine for high-performance HCC treatment.

Developing targeted antioxidant nanomedicines for ischemic penumbra: Novel strategies in treating brain ischemia-reperfusion injury

During cerebral ischemia-reperfusion conditions, the excessive reactive oxygen species in the ischemic penumbra region, resulting in neuronal oxidative stress, constitute the main pathological mechanism behind ischemia-reperfusion damage. Swiftly reinstating blood perfusion in the ischemic penumbra zone and suppressing neuronal oxidative injury are key to effective treatment. Presently, antioxidants in clinical use suffer from low bioavailability, a singular mechanism of action, and substantial side effects, severely restricting their therapeutic impact and widespread clinical usage. Recently, nanomedicines, owing to their controllable size and shape and surface modifiability, have demonstrated good application potential in biomedicine, potentially breaking through the bottleneck in developing neuroprotective drugs for ischemic strokes. This manuscript intends to clarify the mechanisms of cerebral ischemia-reperfusion injury and provides a comprehensive review of the design and synthesis of antioxidant nanomedicines, their action mechanisms and applications in reversing neuronal oxidative damage, thus presenting novel approaches for ischemic stroke prevention and treatment.

Microenvironment-responsive metal-phenolic network release platform with ROS scavenging, anti-pyroptosis, and ECM regeneration for intervertebral disc degeneration

Intervertebral disc degeneration (IVDD) can be caused by aging, injury, and genetic factors. The pathological changes associated with IVDD include the excessive accumulation of reactive oxygen species (ROS), cellular pyroptosis, and extracellular matrix (ECM) degradation. There are currently no approved specific molecular therapies for IVDD. In this study, we developed a multifunctional and microenvironment-responsive metal-phenolic network release platform, termed TMP@Alg-PBA/PVA, which could treat (IL-1β)-induced IVDD. The metal-phenolic network (TA-Mn-PVP, TMP) released from this platform targeted mitochondria to efficiently scavenge ROS and reduce ECM degradation. Pyroptosis was suppressed through the inhibition of the IL-17/ERK signaling pathway. These findings demonstrate the versatility of the platform. And in a rat model of IVDD, TMP@Alg-PBA/PVA exhibited excellent therapeutic effects by reducing the progression of the disease. TMP@Alg-PBA/PVA, therefore, presents clinical potential for the treatment of IVDD.

DDAH1 promotes neurogenesis and neural repair in cerebral ischemia

Choline acetyltransferase (ChAT)-positive neurons in neural stem cell (NSC) niches can evoke adult neurogenesis (AN) and restore impaired brain function after injury, such as acute ischemic stroke (AIS). However, the relevant mechanism by which ChAT+ neurons develop in NSC niches is poorly understood. Our RNA-seq analysis revealed that dimethylarginine dimethylaminohydrolase 1 (DDAH1), a hydrolase for asymmetric NG,NG-dimethylarginine (ADMA), regulated genes responsible for the synthesis and transportation of acetylcholine (ACh) (Chat, Slc5a7 and Slc18a3) after stroke insult. The dual-luciferase reporter assay further suggested that DDAH1 controlled the activity of ChAT, possibly through hypoxia-inducible factor 1α (HIF-1α). KC7F2, an inhibitor of HIF-1α, abolished DDAH1-induced ChAT expression and suppressed neurogenesis. As expected, DDAH1 was clinically elevated in the blood of AIS patients and was positively correlated with AIS severity. By comparing the results among Ddah1 general knockout (KO) mice, transgenic (TG) mice and wild-type (WT) mice, we discovered that DDAH1 upregulated the proliferation and neural differentiation of NSCs in the subgranular zone (SGZ) under ischemic insult. As a result, DDAH1 may promote cognitive and motor function recovery against stroke impairment, while these neuroprotective effects are dramatically suppressed by NSC conditional knockout of Ddah1 in mice.

The Optimization Design of Macrophage Membrane Camouflaging Liposomes for Alleviating Ischemic Stroke Injury through Intranasal Delivery

Ischemic stroke is associated with a high mortality rate, and effective treatment strategies are currently lacking. In this study, we aimed to develop a novel nano delivery system to treat ischemic stroke via intranasal administration. A three-factor Box-Behnken experimental design was used to optimize the formulation of liposomes co-loaded with Panax notoginseng saponins (PNSs) and Ginsenoside Rg3 (Rg3) (Lip-Rg3/PNS). Macrophage membranes were coated onto the surface of the optimized liposomes to target the ischemic site of the brain. The double-loaded liposomes disguised by macrophage membranes (MM-Lip-Rg3/PNS) were spherical, in a "shell-core" structure, with encapsulation rates of 81.41% (PNS) and 93.81% (Rg3), and showed good stability. In vitro, MM-Lip-Rg3/PNS was taken up by brain endothelial cells via the clathrin-dependent endocytosis and micropinocytosis pathways. Network pharmacology experiments predicted that MM-Lip-Rg3/PNS could regulate multiple signaling pathways and treat ischemic stroke by reducing apoptosis and inflammatory responses. After 14 days of treatment with MM-Lip-Rg3/PNS, the survival rate, weight, and neurological score of middle cerebral artery occlusion (MCAO) rats significantly improved. The hematoxylin and eosin (H&E) and TUNEL staining results showed that MM-Lip-Rg3/PNS can reduce neuronal apoptosis and inflammatory cell infiltration and protect the ischemic brain. In vivo biological experiments have shown that free Rg3, PNS, and MM-Lip-Rg3/PNS can alleviate inflammation and apoptosis, especially MM-Lip-Rg3/PNS, indicating that biomimetic liposomes can improve the therapeutic effects of drugs. Overall, MM-Lip-Rg3/PNS is a potential biomimetic nano targeted formulation for ischemic stroke therapy.

Bioorthogonal microglia-inspired mesenchymal stem cell bioengineering system creates livable niches for enhancing ischemic stroke recovery via the hormesis

Mesenchymal stem cells (MSCs) experience substantial viability issues in the stroke infarct region, limiting their therapeutic efficacy and clinical translation. High levels of deadly reactive oxygen radicals (ROS) and proinflammatory cytokines (PC) in the infarct milieu kill transplanted MSCs, whereas low levels of beneficial ROS and PC stimulate and improve engrafted MSCs' viability. Based on the intrinsic hormesis effects in cellular biology, we built a microglia-inspired MSC bioengineering system to transform detrimental high-level ROS and PC into vitality enhancers for strengthening MSC therapy. This system is achieved by bioorthogonally arming metabolic glycoengineered MSCs with microglial membrane-coated nanoparticles and an antioxidative extracellular protective layer. In this system, extracellular ROS-scavenging and PC-absorbing layers effectively buffer the deleterious effects and establish a micro-livable niche at the level of a single MSC for transplantation. Meanwhile, the infarct's inanimate milieu is transformed at the tissue level into a new living niche to facilitate healing. The engineered MSCs achieved viability five times higher than natural MSCs at seven days after transplantation and exhibited a superior therapeutic effect for stroke recovery up to 28 days. This vitality-augmented system demonstrates the potential to accelerate the clinical translation of MSC treatment and boost stroke recovery.

Inflammatory Pathogenesis of Post-stroke Depression

Post-stroke depression (PSD) is a complex mood disorder that emerges in individuals following a stroke, characterized by the development of depressive symptoms. The pathogensis of PSD is diverse, with inflammation playing a vital role in its onset and progression. Emerging evidence suggests that microglial activation, astrocyte responses, nuclear factor κB(NF-κB) signaling, dysregulation of the hypothalamic pituitary adrenal (HPA) axis, alterations in brain-derived neurotrophic factor (BDNF) expression, neurotransmitter imbalances, adenosine triphosphate (ATP) and its receptors and oxidative stress are intricately linked to the pathogenesis of PSD. The involvement of inflammatory cytokines in these processes highlights the significance of the inflammatory pathway. Integrating these hypotheses, the inflammatory mechanism offers a novel perspective to expand therapeutic strategies for PSD.

Bioactive Ceria Nanoenzymes Target Mitochondria in Reperfusion Injury to Treat Ischemic Stroke

Overproduction of reactive oxygen species by damaged mitochondria after ischemia is a key factor in the subsequent cascade of damage. Delivery of therapeutic agents to the mitochondria of damaged neurons in the brain is a potentially promising targeted therapeutic strategy for the treatment of ischemic stroke. In this study, we developed a ceria nanoenzymes synergistic drug-carrying nanosystem targeting mitochondria to address multiple factors of ischemic stroke. Each component of this nanosystem works individually as well as synergistically, resulting in a comprehensive therapy. Alleviation of oxidative stress and modulation of the mitochondrial microenvironment into a favorable state for ischemic tolerance are combined to restore the ischemic microenvironment by bridging mitochondrial and multiple injuries. This work also revealed the detailed mechanisms by which the proposed nanodelivery system protects the brain, which represents a paradigm shift in ischemic stroke treatment.

Dextran-based micelles for combinational chemo-photodynamic therapy of tumors via in vivo chemiluminescence

Natural polysaccharides, represented by dextran, chitosan, and hyaluronic acid, are widely approved for use as pharmaceutical excipients and are important carrier materials for the design of advanced drug delivery systems, particularly in the field of anticancer drug delivery. The combination of stimuli-activable prodrug based chemotherapy and photodynamic therapy (PDT) has attracted increasing attention. Recent studies have verified the effectiveness of this strategy in the treatment of multiple aggressive cancers. However, in such combination, the stimuli-responsive chemotherapy and PDT have their own problems that need to be overcome. The uneven distribution of endogenous stimuli within tumor tissues makes it difficult for prodrug to be completely activated. And the inadequate tissue penetration depth of external light results in low efficiency of PDT. Aiming at these two bottlenecks, we designed a biocompatible dextran based - multi-component nanomedicine (PCL-NPs) that integrate a chemiluminescence agent luminol, a photosensitizer chlorine e6 (Ce6), and a reactive oxygen species (ROS)-activable thioketal-based paclitaxel (PTX) prodrug. The presence of overexpressed hydrogen peroxide (H2O2) inside tumor oxidizes the luminol moiety to generate in-situ light for PDT through chemiluminescence resonance energy transfer (CRET). The singlet oxygen (1O2) produced in this process not only directly kills tumor cells but also amplifies oxidative stress to accelerate the activation of PTX prodrug. We propose that the PCL-NPs have great therapeutic potential by simultaneously enhancing chemotherapy and PDT in a combination therapy.