Theranostics最新文献

Rationale: Acute glaucoma is triggered by sudden spikes in intraocular pressure, which induces retinal ischemia/reperfusion (RI/R), leading to hypoxia, oxidative stress, and ultimately PANoptosis in retinal ganglion cells (RGCs). Developing a therapeutic approach that simultaneously targets these events may offer a promising strategy for reducing secondary neuronal damage in acute glaucoma. Methods: We developed a reactive oxygen species (ROS)/hypoxia dual-responsive, biodegradable nanoparticle system (NPs) containing azo and thioketal bonds, designed to encapsulate melatonin (MT), a known endogenous antioxidant and PANoptosis inhibitor. The biocompatibility, biosafety, and therapeutic efficacy of MT-NPs were evaluated in vitro using an oxygen-glucose deprivation/reperfusion (OGD/R) R28 cell model and in vivo using a RI/R rat model. Results: The NPs efficiently released encapsulated MT in response to hypoxic conditions and the presence of ROS. This controlled-release system improved both the biocompatibility and long-term retention of MT in the retina. MT-NPs effectively alleviated hypoxia, cleared excess ROS, and inhibited PANoptosis in RGCs following acute glaucomatous injury. Compared to direct MT administration, MT-NPs were more effective at protecting RGC axons and somas and facilitating restoration of visual function in rats with acute glaucoma. Conclusion: This simplified but multifunctional delivery system leveraged the widely available and safe compound melatonin in a highly efficient nanoparticle platform. This system offers potent neuroprotective effects to the retina preventing injury caused by acute glaucoma, and thereby providing a promising clinically translatable strategy for the treatment of glaucoma.

Rationale: Myocardial ischemia-reperfusion (I/R) injury remains a major clinical challenge that limits the efficacy of reperfusion therapy in acute myocardial infarction, mainly due to excessive production of reactive oxygen species (ROS) and the resulting oxidative stress, inflammation, and cardiomyocyte death. However, conventional antioxidant strategies show limited clinical efficacy, highlighting the urgent need for novel redox-regulating therapies. Methods: We synthesized carbon dot nanozymes (SM-CDs) via a green hydrothermal process using Salvia miltiorrhiza, a traditional Chinese medicinal herb. Their size, structure, and antioxidant enzymatic activities were thoroughly characterized. The contribution of surface functional groups to the superoxide dismutase (SOD)-like activity of SM-CDs were investigated by surface modification. In vitro antioxidant, anti-inflammatory, and anti-apoptotic effects were evaluated in RAW264.7 macrophages and H9C2 cardiomyocytes. In vivo therapeutic effects were accessed in a rat myocardial I/R model. Transcriptomics analysis was used to explore underlying cardioprotective mechanisms. Network pharmacology analysis was employed to study potential pharmacological activity inherited from the herbal precursor. Results: SM-CDs exhibit potent ROS-scavenging capacity, with surface carbonyl and hydroxyl groups playing key roles in their remarkable SOD-like activity. In vitro, SM-CDs effectively scavenged intracellular ROS, suppressed macrophage M1 polarization, and attenuated cardiomyocyte apoptosis. In vivo, intramyocardial injection of SM-CDs significantly reduced inflammation, apoptosis, and infarct size, while improving cardiac remodeling and functional recovery through fibrosis inhibition and enhanced neovascularization. These effects were potentially associated with inhibition of NF-κB and NOD-like receptor signaling pathways and activation of PI3K-Akt and FoxO pathways. Strong pathway concordance between SM-CD-regulated pathways and known therapeutic targets of Salvia miltiorrhiza suggests that SM-CDs may retain pharmacological activity from their herbal precursor. Conclusions: This study introduces SM-CDs as biocompatible nanozymes with potent antioxidant and cardioprotective potential for myocardial I/R injury.

Background: The healing of chronically infected wounds is severely hindered by persistent inflammation, bacterial infection, and oxidative stress, posing great challenges to clinical therapy. To address these challenges, we designed a multifunctional dual-layer microneedles patch (MN@DOX+RES) featuring reactive oxygen species (ROS) responsiveness and dual drug delivery capabilities. This patch is engineered to deliver synergistic antibacterial, anti-inflammatory, and antioxidant effects, thereby promoting the healing of infected wounds. Methods: The dual-layer microneedles patch comprises a rapidly dissolvable HA backing layer loaded with DOX and a ROS-responsive tips layer composed of a crosslinked AHA-PBA/PVA matrix that encapsulates water-soluble RES inclusion complexes. A series of in vitro experiments was conducted to evaluate the mechanical strength, biocompatibility, antibacterial activity against Staphylococcus aureus and Escherichia coli, antioxidant performance, and macrophage polarization. In vivo evaluations were performed on rat models with infected skin wounds. Results: The MN@DOX+RES microneedles exhibited strong skin penetration ability and excellent mechanical strength. It significantly inhibited bacterial growth, efficiently scavenged free radicals, reduced intracellular ROS levels, and enhanced M2 macrophage polarization. In vivo, the patch accelerated wound closure, suppressed the inflammatory cytokine IL-6, enhanced IL-10 expression, and activated the Keap1/Nrf2/HO-1 antioxidant signaling pathway. Conclusions: This study proposes an innovative therapeutic strategy that combines dual-drug delivery, oxidative microenvironment regulation, and immune modulation to promote the healing of chronic infected wounds. The MN@DOX+RES microneedles system demonstrates great potential in overcoming clinical challenges associated with infection, inflammation, and the limitations of conventional therapeutic approaches.

Rationale: Emerging evidence implicates the gut microbiota in epilepsy pathogenesis through the microbiota-gut-brain axis, yet the functional contribution of specific microbial taxa to epileptogenesis remains unclear. This study aimed to investigate whether Lachnospira eligens (L. eligens) can alleviate epileptic activity by modulating the gut-brain axis, with a focus on intestinal barrier integrity, blood-brain barrier (BBB) integrity, and neuroimmune responses. Methods: Using a cobalt wire-induced rat epilepsy model, we performed fecal 16S rDNA sequencing to assess gut microbiota alterations. Rats received daily oral gavage of L. eligens or PBS for 15 days, with colonization confirmed by qPCR. Seizure activity was monitored using long-term video electroencephalogram (EEG) and Racine scores. Barrier function, systemic inflammation, and microglial activation were assessed using FITC-dextran (FD-4, 4 kDa) assay, Western blotting (WB), immunohistochemistry (IHC), immunofluorescence (IF), ELISA, and qPCR. Serum short-chain fatty acids (SCFAs) were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Epileptic rats exhibited early gut microbiota dysbiosis, with a significant decline in Lachnospira abundance both preceding and succeeding seizure onset (P = 0.041, P = 0.026). L. eligens stably colonized the gut (Day 6 and Day 15, both P < 0.001). Supplementation significantly reduced grade 4-5 seizure frequency (P = 0.002) and prolonged seizure latency (P = 0.005). Barrier integrity improved, as indicated by lower plasma FD-4 (P < 0.001), increased colonic (WB: P = 0.013; IHC: P = 0.003) and cortical occludin expression (WB: P = 0.002; IHC: P = 0.01), and decreased serum lipopolysaccharide-binding protein (LBP) (P = 0.011). Neuroinflammation was attenuated, including reduced microglial activation (P = 0.048), lower pro-inflammatory cytokines (IL-1β, P = 0.047; IL-6, P = 0.001; TNF-α, P = 0.002), and decreased M1 polarization (P = 0.004). Serum butyrate increased (P = 0.014), and SCFAs, especially butyrate, suppressed lipopolysaccharide (LPS)-induced iNOS (P = 0.031) in BV2 cells. Conclusions: These findings demonstrate that L. eligens mitigates epileptic activity by restoring intestinal barrier and BBB integrity and suppressing neuroinflammation. Our study highlights L. eligens as a promising microbiota-based intervention for epilepsy through modulation of the gut-brain axis.

Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disorder that typically affects young adults and is primarily characterized by demyelinating lesions in the central nervous system (CNS). According to the Revised McDonald Criteria, the clinical diagnosis of MS can be established based on a combination of clinical observations, the presence of focal lesions in at least two distinct CNS areas on magnetic resonance imaging (MRI) and the detection of specific oligoclonal bands in the cerebrospinal fluid. Conventional MRI remains a cornerstone of MS diagnosis and disease monitoring, providing high-resolution assessments of lesion burden and brain atrophy. In addition, advanced MRI methods are increasingly applied in research settings to probe myelin integrity, iron deposition, and biochemical changes, with the potential to complement established diagnostic workflows in the future. Despite remarkable advances in the management of MS over the past two decades, complex differential diagnoses and the lack of effective imaging tools for therapy monitoring remain major obstacles, thus channeling the development of innovative molecular imaging probes that can be harnessed in clinical practice. Indeed, positron emission tomography (PET) has a significant potential to advance the contemporary diagnosis and management of MS. Given the solid body of evidence implicating myelin dysfunction in the pathophysiology of MS, myelin-targeted imaging probes have been developed, and are currently under clinical evaluation for MS diagnosis and therapy monitoring. In parallel, ligands for the 18 kDa translocator protein (TSPO) and the cannabinoid receptor type 2 (CB2R) have been employed to capture neuroinflammatory processes by visualizing microglial activation, while other tracers allow the assessment of synaptic integrity across various disease stages of MS. Further, PET probes have been employed to delineate the role of activated microglia and facilitate the assessment of synaptic dysfunction across all disease stages of MS. This review discusses the challenges and opportunities of translational molecular imaging by highlighting key molecular concepts that are currently leveraged for diagnostic imaging, patient stratification, therapy monitoring and drug development in MS. Moreover, we shed light on potential future developments that hold promise to advance our understanding of MS pathophysiology, with the ultimate goal to provide the best possible patient care for every individual MS patient.

Rationale: The efficacy of radiotherapy in triple-negative breast cancer (TNBC) is often limited by an immunosuppressive tumor microenvironment (TME), requiring high radiation doses that cause systemic toxicity. There is a critical need for theranostic strategies capable of guiding therapy and amplifying the efficacy of low-dose radiation. Methods: We developed a multifunctional organolutetium nanosensitizer (LSPA) for image-guided, low-dose radioimmunotherapy. Lutetium (Lu) serves as both a contrast agent for CT imaging and a radiosensitizer through the generation of reactive oxygen species (ROS). The LSPA nanoparticles were engineered to selectively accumulate in tumors and release their therapeutic payload in response to the acidic TME. Results: At a low 6 Gy X-ray dose, LSPA synergized with the PARP inhibitor Olaparib to induce extensive DNA damage. This activated the cGAS-STING pathway and remodeled the TME. The treatment promoted immunogenic cell death, dendritic cell maturation, and M1 macrophage repolarization. It also decreased regulatory T cells, leading to increased CD4⁺ and CD8⁺ T cell infiltration in both primary and metastatic tumors. Conclusion: This theranostic strategy suppressed primary and distant (abscopal) tumors, prevented recurrence, and established durable immune memory with low-dose irradiation. Our findings present a clinically translatable approach that combines a nanosensitizer with PARP inhibition to turn immunologically "cold" tumors into "hot" ones, thereby enhancing the efficacy of low-dose radioimmunotherapy while limiting systemic toxicity.

Rationale: The integration of biological and physical interventions represents a promising therapeutic strategy for spinal cord injury (SCI), offering a novel approach to restore disrupted motor pathways. This study investigates whether repetitive transcranial magnetic stimulation (rTMS) can prevent cerebral neuroapoptosis and promote the regeneration and integration of brain-derived nerve fibers with neural network tissueoids (NNToids) following SCI. Methods: Neural stem cell-derived NNToids were transplanted into rats with complete SCI and simultaneously treated with 10 Hz rTMS. Neuroinflammatory responses, neuroapoptosis, neuronal activation, and axonal regeneration were systematically evaluated using transcriptomic sequencing, histological validation, Western blotting, and neural tract tracing. The responsiveness of NNToids to 10 Hz rTMS in facilitating motor neural pathway reconstruction was also assessed. Results: 10 Hz rTMS significantly enhanced cFOS expression in layer V pyramidal neurons of the sensorimotor cortex (SMC), markedly reduced microglial activation and neuroapoptosis, and upregulated the expression of mitochondrial-related protein TOM20, axonal regeneration marker p-S6, and synaptic plasticity-associated protein Arc in SMC neurons. NNToids facilitated the ingrowth of corticospinal tract (CST) and 5-hydroxytryptamine (5-HT) - positive nerve fibers into the transplantation site. Retrograde PRV tracing demonstrated that 10 Hz rTMS enhanced the capacity of NNToid neurons to relay CST and 5-HT signals to hindlimb motor neurons. Functional assessments and cortical motor evoked potentials confirmed that the rTMS-NNToid combination improved the transmission of motor-related neural signals to the hindlimbs. Histological analysis further demonstrated that activated NNToid neurons exhibited increased expression of N-methyl-D-aspartate receptors (NMDAR) and formed more synaptic connections with vGluT-positive axon terminals. Conclusion: These findings demonstrate that rTMS mitigates motor cortex inflammation, promotes the regeneration and integration of brain-derived nerve fibers with NNToid neurons, thereby establishing a foundation for motor function recovery. Moreover, the study identifies the mechanism through which NNToid neurons mediate motor neural pathway reconstruction under rTMS modulation. Although based on a rat model, this work provides a promising framework for future biophysical therapies that combine patient-derived autologous iPSC-based NNToids with non-invasive brain stimulation.

Background: Huntington's disease (HD) is a devastating neurodegenerative disorder caused by CAG repeat expansion in the HTT gene, resulting in a polyglutamine-expanded huntingtin (HTT) protein that forms toxic aggregates. Although heat-shock proteins are known to facilitate the refolding or clearance of misfolded proteins, their precise role in modulating protein aggregation in HD remains unclear. Here, we explore the function of caseinolytic peptidase B (ClpB), a mitochondrial AAA+ ATPase and heat-shock protein, in maintaining proteostasis and synaptic integrity in HD. Methods: We examined how CLPB loss or overexpression in human embryonic kidney 293T (HEK293T) cells impacted the aggregation of wild-type HTT (HTT-Q23) and mutant HTT (HTT-Q79). In parallel, AAV-mediated ClpB knockdown or overexpression was applied to the striatum of HD model mice. and HTT aggregation and inhibitory synaptic alterations were assessed. Aggregate burden was quantified via immunostaining, and inhibitory synapse density was evaluated using VGAT immunohistochemistry and electrophysiological recordings. Results: In HEK293T cells, CLPB knockout led to abnormal aggregation of HTT-Q23 while CLPB overexpression reduced the size of HTT-Q79 aggregates. In the mouse striatum, ClpB knockdown increased HTT-Q23 aggregate numbers and altered HTT-Q79 aggregation morphology, whereas CLPB overexpression restored the density and size of VGAT-positive inhibitory synapses and improved inhibitory synaptic transmission in HD model mice. These effects of CLPB overexpression were associated with a reduced mitochondrial aggregation burden, suggesting that ClpB contributes to mitochondrial protein quality control. Conclusions: These results demonstrate that ClpB regulates both physiological and pathological HTT aggregation and contributes to maintaining inhibitory synaptic integrity. By modulating mitochondrial proteostasis, ClpB acts as a protective factor in HD pathology, highlighting its potential as a therapeutic target for neurodegenerative disorders characterized by protein misfolding.

Rationale: Phospholipase A2 receptor (PLA2R) is the predominant autoantigen in primary membranous nephropathy (PMN), accounting for approximately 70% of clinical cases. However, the mechanisms by which PLA2R initiates and sustains autoimmunity in PMN remain unclear. PLA2R belongs to the mannose receptor (MR) family, members of which have been shown to undergo endocytosis and lysosomal degradation for MHCII-mediated antigen presentation. This study investigates whether antibody binding promotes PLA2R internalization and lysosomal processing to enhance MHCII-mediated antigen presentation and CD4⁺ T cell activation, thereby contributing to the perpetuation of autoimmunity in PMN. Methods: Multiple PLA2R-overexpressing cell lines were generated by lentiviral-mediated overexpression of PLA2R. Imaging and western blot were employed to assess the effects of anti-PLA2R antibodies, derived from PMN patients or produced in-house, on PLA2R internalization and degradation. To define the specific endocytic pathway involved, we used pharmacological inhibitors of endocytosis as well as PLA2R constructs lacking the endocytic domain. Finally, T cell activation was evaluated using OT-II CD4⁺ T cells co-cultured with PLA2R-ovalbumin (OVA)-expressing mouse dendritic cells treated with anti-PLA2R antibodies. Results: Binding of anti-PLA2R antibodies triggers clathrin-mediated endocytosis and lysosomal trafficking of PLA2R. Antibody-induced PLA2R degradation was effectively prevented by specific endocytosis inhibitors or by deletion of the PLA2R endocytic domain. Furthermore, PLA2R-OVA-expressing mouse dendritic cells exposed to PLA2R antibodies enhanced the activation of OVA-specific CD4⁺ T cells both in vitro and in vivo. Conclusions: This study demonstrates that anti-PLA2R antibody induces internalization and lysosomal degradation of PLA2R, a process that may enhance MHC class II-mediated antigen presentation and promote the expansion of antigen-specific CD4⁺ T cells. This mechanism could establish a self-reinforcing feedback loop that perpetuates autoimmune responses in PMN.

Rationale: In ulcerative colitis (UC), microbial products or metabolites, coupled with inflammatory stimuli, result in simultaneous damage to both the intestinal epithelial barrier (IEB) and gut vascular barrier (GVB). Current UC treatments usually focus on modulating IEB, whereas GVB-which critically regulates the translocation of gut microbiota and metabolites into systemic circulation-has been largely overlooked. Here, we developed a facile, biomimetic strategy to engineer anti-inflammatory berberine/magnolol self-assembled nanoparticles (BM NPs) using macrophage membrane camouflage, enabling targeted UC accumulation and dual restoration of both the IEB and GVB. Methods: BM NPs employing macrophage membranes to camouflage mimetic nanoplatform. The mimetic nanoplatform on targeting capacity of inflamed intestinal epithelial cells, M1/M2 polarization, macrophage and intestinal epithelial cell inflammatory factors, and vascular endothelial cell migration and tube-forming were evaluated in vitro. Furthermore, its therapeutic efficacy was assessed in a mice UC model, demonstrating significant reductions in bacterial translocation, restoration of both the IEB and GVB, and modulation of the inflammatory immune microenvironment. Results: The biomimetic nanoplatform demonstrates superior targeting specificity and prolonged retention in inflamed intestinal epithelium and vascular tissues. Macrophage membranes achieve GVB repair by mechanical traction and physical adsorption of inflammatory factors. Besides, efficient delivery of the loaded anti-inflammatory drugs also achieves the repair of the IEB. GVB repair effectively prevents systemic dissemination of gut-derived microbes and their metabolites, thereby attenuating UC-induced inflammatory cascades. Collectively, this approach significantly ameliorates colonic pathology in UC. Conclusion: Our study proposes the synergistic repair of IEB and GVB through the mechanical traction and physical adsorption of macrophage membranes, assisted by anti-inflammatory components, which provide new insights as well as a new paradigm for the treatment of UC.