Background: The incidence of ischemic stroke in the context of vascular disease is high, and the expression of growth-associated protein-43 (GAP43) increases when neurons are damaged or stimulated, especially in a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R).Experimental: design: We bioengineered neuron-targeting exosomes (Exo) conjugated to a monoclonal antibody against GAP43 (mAb GAP43) to promote the targeted delivery of quercetin (Que) to ischemic neurons with high GAP43 expression and investigated the ability of Exo to treat cerebral ischemia by scavenging reactive oxygen species (ROS).Results: Our results suggested that Que loaded mAb GAP43 conjugated exosomes (Que/mAb GAP43-Exo) can specifically target damaged neurons through the interaction between Exo-delivered mAb GAP43 and GAP43 expressed in damaged neurons and improve survival of neurons by inhibiting ROS production through the activation of the Nrf2/HO-1 pathway. The brain infarct volume is smaller, and neurological recovery is more markedly improved following Que/mAb GAP43-Exo treatment than following free Que or Que-carrying exosome (Que-Exo) treatment in a rat induced by MCAO/R.Conclusions: Que/mAb GAP43-Exo may serve a promising dual targeting and therapeutic drug delivery system for alleviating cerebral ischemia/reperfusion injury.
Background: Ischemic stroke is a serious cerebrovascular disease with high morbidity and disability. Zinc accumulation has been shown to play a vital role in neuronal death and blood–brain barrier damage following ischemia in acute stage. However, almost nothing is known about whether zinc is involved in neurological recovery in ischemic prolonged period. This study investigates whether zinc promotes neurological recovery through astrocytes‐induced angiogenesis during ischemic repair phase.Methods: Sprague–Dawley rats were subjected to 2 h ischemia/14, 21, and 28 days reperfusion by middle cerebral artery occlusion, then administered ZnCl2 (10 mg/kg) via intraperitoneally daily from 7 days to tissue collection to observe brain tissue morphology, neurological function recovery by cortical width index, Adhesive removal test, and Forelimb placing test. Angiogenesis, astrocyte activation, and HIF‐1α/VEGF pathway were assessed via Western blot, immunofluorescence, and BrdU method in vivo and in vitro.Results: The results showed that zinc significantly alleviated brain atrophy and improved neurological function recovery during the cerebral ischemia repair stage. Zinc significantly increased the protein levels of HIF‐1α, VEGF‐A, and VEGF‐R2 in astrocytes, and promoted angiogenesis during cerebral ischemia repair. In vitro and in vivo studies confirmed that zinc promoted angiogenesis via the astrocyte‐mediated HIF‐1α/VEGF signaling pathway.Conclusions: Zinc significantly improves neurological function recovery during the cerebral ischemia repair stage, providing new evidence supporting zinc as a potential therapeutic target for ischemic stroke by promoting astrocyte induced angiogenesis.
JOURNAL/nrgr/04.03/01300535-202310000-00030/figure1/v/2026-05-25T160659Z/r/image-tiff Exosomes derived from human bone marrow mesenchymal stem cells (MSC-Exo) are characterized by easy expansion and storage, low risk of tumor formation, low immunogenicity, and anti-inflammatory effects. The therapeutic effects of MSC-Exo on ischemic stroke have been widely explored. However, the underlying mechanism remains unclear. In this study, we established a mouse model of ischemic brain injury induced by occlusion of the middle cerebral artery using the thread bolt method and injected MSC-Exo into the tail vein. We found that administration of MSC-Exo reduced the volume of cerebral infarction in the ischemic brain injury mouse model, increased the levels of interleukin-33 (IL-33) and suppression of tumorigenicity 2 receptor (ST2) in the penumbra of cerebral infarction, and improved neurological function. In vitro results showed that astrocyte-conditioned medium of cells deprived of both oxygen and glucose, to simulate ischemia conditions, combined with MSC-Exo increased the survival rate of primary cortical neurons. However, after transfection by IL-33 siRNA or ST2 siRNA, the survival rate of primary cortical neurons was markedly decreased. These results indicated that MSC-Exo inhibited neuronal death induced by oxygen and glucose deprivation through the IL-33/ST2 signaling pathway in astrocytes. These findings suggest that MSC-Exo may reduce ischemia-induced brain injury through regulating the IL-33/ST2 signaling pathway. Therefore, MSC-Exo may be a potential therapeutic method for ischemic stroke.
Background: Ischemic stroke leads a primary cause of mortality in human diseases, with a high disability rate worldwide. This study aims to investigate the function of β‐1,4‐galactosyltransferase 1 (B4galt1) in mouse brain ischemia/reperfusion (I/R) injury.Methods: Recombinant human B4galt1 (rh‐B4galt1) was intranasally administered to the mice model of middle cerebral artery occlusion (MCAO)/reperfusion. In this study, the impact of rh‐B4galt1 on cerebral injury assessed using multiple methods, including the neurological disability status scale, 2,3,5‐triphenyltetrazolium chloride (TTC), Nissl and TUNEL staining. This study utilized laser speckle Doppler flowmeter to monitor the cerebral blood flow. Western blotting was performed to assess the protein expression levels, and fluorescence‐labeled dihydroethidium method was performed to determine the superoxide anion generation. Assay kits were used for the measurement of iron, malondialdehyde (MDA) and glutathione (GSH) levels.Results: We demonstrated that rh‐B4galt1 markedly improved neurological function, reduced cerebral infarct volume and preserved the completeness of blood–brain barrier (BBB) for preventing damage. These findings further illustrated that rh‐B4galt1 alleviated oxidative stress, lipid peroxidation, as well as iron deposition induced by I/R. The vital role of ferroptosis was proved in brain injury. Furthermore, the rh‐B4galt1 could increase the levels of TAZ, Nrf2 and HO‐1 after I/R. And TAZ‐siRNA and ML385 reversed the neuroprotective effects of rh‐B4galt1.Conclusions: The results indicated that rh‐B4galt1 implements neuroprotective effects by modulating ferroptosis, primarily via upregulating TAZ/Nrf2/HO‐1 pathway. Thus, B4galt1 could be seen as a promising novel objective for ischemic stroke therapy.