Edaravone Dexborneol protects against blood-brain barrier disruption following cerebral ischemia/reperfusion by upregulating pericyte coverage via vitronectin-integrin and PDGFB/PDGFR-β signaling.

Recent advancements in brain cytoprotection therapies following cerebral ischemia-reperfusion (I/R) injury have become an emerging interest. Pericytes were vulnerable during the early stages of ischemia. This study aims to explore the protective effects of Edaravone dexborneol (Eda.B) on pericyte loss, as well as and the underlying mechanisms, given its potential in alleviating I/R injury. The rat transient middle cerebral artery occlusion (tMCAO) model was established. Rats were randomly divided into Sham group (Sham, n = 24), tMCAO group (tMCAO, n = 24), Edaravone group (Eda, n = 24), Dexborneol group (Dexborneol, n = 24), and Eda.B group (Eda.B, n = 24). Neurological function recovery, infarct volume, and blood-brain barrier (BBB) disruption were assessed using Zea-Longa scoring, TTC staining, and Evans Blue extravasation, respectively. Alterations in Basement membrane (BM) and pericyte coverage were assessed by transmission electron microscopy (TEM). The expression levels of pericyte marker NG2 and PDGFR-β in the ischemic region, as well as BBB transcellular transport-related proteins vitronectin (VTN), α5 and PDGFB were detected by western blotting. Furthermore, a specific inhibitor of PDGFB, MOR8457, was employed (Eda.B + MOR8457, n = 8) to explore the protective effects of Eda.B on pericyte injury via PDGFB/PDGFR-β. Eda.B significantly reduced cerebral infarct volume and promoted neurological function recovery in comparison to the tMCAO, Eda and Dexborneol groups. Additionally, Eda.B significantly ameliorated BBB leakage, mitigated the decrease in pericyte coverage, and reduced vesicle density in endothelial cells and BM thickness following I/R. Mechanically, Eda.B inhibited the downregulation of NG2, PDGFB/PDGFR-β, VTN, while preventing upregulation of α5 protein expression in tMCAO rats. Blocking PDGFB with MOR8457 demonstrated that Eda.B improved pericyte loss and BBB permeability by activating PDGFB/PDGFR-β signaling. We elucidated that vitronectin-integrin and PDGFB/PDGFR-β signaling contributed to Eda.B's protective effects against pericyte loss and BBB permeability following I/R injury, unraveling new insights into mechanisms of pericyte as a promising therapeutic target.

Sun Z ，Zhao H ，Yang S ，Liu R ，Yi L ，Gao J ，Liu S ，Chen Y ，Zhang Z ... -  《-》

Piezo1 Modulates Neuronal Autophagy and Apoptosis in Cerebral Ischemia-Reperfusion Injury Through the AMPK-mTOR Signaling Pathway.

Cerebral ischemia-reperfusion (I/R) injury is a complex pathophysiological process involving multiple mechanisms, including apoptosis and autophagy, which can lead to significant neuronal damage. PIEZO1, a stretch-activated ion channel, has recently emerged as a potential regulator of cellular responses to ischemic conditions. However, its role in neuronal cell survival and death during ischemic events is not well elucidated. This study aimed to ascertain the regulatory function of PIEZO1 in neuronal cell apoptosis and autophagy in an in vitro model of hypoxia-reoxygenation and an in vivo model of brain I/R injury. HT22 hippocampal neuronal cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to simulate ischemic conditions, with subsequent reoxygenation. In vitro, PIEZO1 expression was silenced using small interfering RNA (si-RNA) transfection. The effects on cell viability, apoptosis, and autophagy were assessed using CCK-8 assays, PI-Annexin/V staining combined with flow cytometry, and Western blot analysis. Additionally, intracellular Ca2+ levels in HT22 cells were measured using a Ca2+ probe. The involvement of the AMPK-mTOR pathway was investigated using rapamycin. For in vivo validation, middle cerebral artery occlusion/reperfusion (MCAO/R) in rats was employed. To determine the neuroprotective role of PIEZO1 silencing, sh-PIEZO1 adeno-associated virus was stereotaxically injected into the cerebral ventricle, and neurological and histological outcomes were assessed using neurological scoring, TTC staining, H&E staining, Nissl staining, and immunofluorescence. In HT22 cells, OGD/R injury notably upregulated PIEZO1 expression and intracellular Ca2+ levels. Silencing PIEZO1 significantly diminished OGD/R-induced Ca2+ influx, apoptosis, and autophagy, as indicated by lower levels of pro-apoptotic and autophagy-related proteins and improved cell viability. Additionally, PIEZO1 modulated the AMPK-mTOR signaling pathway, an effect that was counteracted by rapamycin treatment, implying its regulatory role. In vivo, PIEZO1 silencing ameliorated brain I/R injury in MCAO/R rats, demonstrated by improved neurological function scores and reduced neuronal apoptosis and autophagy. However, these neuroprotective effects were reversed through rapamycin treatment. Our findings indicate that PIEZO1 is upregulated following ischemic injury and facilitates Ca2+ influx, apoptosis, and autophagy via the AMPK-mTOR pathway. Silencing PIEZO1 confers neuroprotection against I/R injury both in vitro and in vivo, highlighting its potential as a therapeutic target for stroke management.

Yue Y ，Chen P ，Ren C 《-》

Synergistic effects of repeated transcranial magnetic stimulation and mesenchymal stem cells transplantation on alleviating neuroinflammation and PANoptosis in cerebral ischemia.

Neuronal death is the primary cause of poor outcomes in cerebral ischemia. The inflammatory infiltration in the early phase of ischemic stroke plays a vital role in triggering neuronal death. Either transplantation of mesenchymal stem cells (MSCs) derived from humans or repetitive transcranial magnetic stimulation (rTMS) have respectively proved to be neuroprotective and anti-inflammatory in cerebral ischemia. However, either treatment above has its limitations. Whether these two therapies have synergistic effects on improving neurological function and the underlying mechanisms remains unclear. This investigation aims to elucidate the synergistic effects and underlying mechanisms of MSCs combined with rTMS treatment on the neurological function recovery post-ischemia. A Sprague-Dawley rat model of cerebral infarction was induced via transient middle cerebral artery occlusion (tMCAO). The rats were divided into five groups (n = 50): sham, tMCAO, rTMS, MSCs, and MSCs + rTMS groups. Transplantation of human umbilical cord MSCs and rTMS intervention were performed 24 h post-stroke. Neurological function was further assessed via several behavioral tests and the 2,3,5-triphenyltetrazolium chloride (TTC) staining companied with Nissl staining were used to assess neuronal survival. TUNEL staining, western blotting, immunofluorescence, immunohistochemistry, ELISA, and flow cytometry were employed to measure the levels of neuroinflammation and PANoptosis. The molecular mechanisms underlying the special role of rTMS in the combined therapy were distinguished with transcriptome sequencing via PC12 cells in oxygen-glucose deprivation/reoxygenation (OGD/R) conditions. The combined therapy efficiently reduced lesion volume and improved neuronal survival (P < 0.05), subsequently improving functional recovery after ischemic stroke. MSCs + rTMS treatment ameliorated the PANoptosis in neurons (P < 0.05), accompanied by decreased levels of inflammatory factors in the cerebral tissue and serum during the subacute phase of cerebral infarction. To further explore the roles of either therapy on synergistic effect, we found that the transplanted MSCs primarily localized in the spleen and reduced cerebral inflammatory infiltration after ischemia via suppressed splenic inflammation. Meanwhile, rTMS significantly protects neurons from PANoptosis in MSCs-inhibited inflammatory conditions by downregulating REST unveiled by transcriptome sequencing. Our study elucidates an unidentified mechanism by which the combination of MSCs and rTMS could synergistically promote neuronal survival and suppress neuroinflammation during the subacute phase of cerebral infarction, thus improving neurological outcomes. The downregulating REST induced by rTMS may potentially contribute to the neuroprotective effect against PANoptosis in MSCs-inhibited inflammatory conditions. These results are expected to provide novel insights into the mechanisms of MSCs and rTMS combination therapy in synergistically protecting against cerebral ischemia injury and potential targets underlying neuronal PANoptosis in the early phase of stroke.

Cheng S ，Lu Q ，Liu Q ，Ma Y ，Chen J ，Lu D ，Huang M ，Huang Y ，Zhao E ，Luo J ，Zheng H ... -  《-》

Expression of NGF, proNGF, p75(NTR) in lung injury induced by cerebral ischemia-reperfusion in young and elderly rats.

This study aims to investigate the expression levels of Nerve Growth Factor (NGF), the precursor form of NGF (proNGF), and p75 neurotrophin receptor (p75NTR) in lung injury induced by cerebral Ischemia-Reperfusion (I/R) in both young and elderly rats. Male Sprague-Dawley rats, categorized as young (3-months-old) and elderly (16-months-old), were divided into four experimental groups: Young Sham, Young I/R, Elderly Sham, and Elderly I/R. Each group underwent either sham surgery or ischemia-reperfusion treatment. Following 24 h post-procedure, the severity of cerebral ischemia was assessed using the Zea Longa 5-point scoring system, and lung tissue pathological changes were examined using Hematoxylin and Eosin (HE) staining. Western blot analysis was utilized to measure the expression levels of NGF, proNGF, and p75NTR proteins in lung tissue. Both young and elderly I/R groups exhibited lung tissue congestion and edema compared to their respective sham groups, with a significant increase in pathological scores (p < 0.05). Furthermore, the elderly I/R group demonstrated a significantly higher pathological score compared to the young I/R group (p < 0.05). Western blot analysis revealed that compared to the young sham group, the expression of NGF in the lung tissue of elderly sham rats decreased (p < 0.05), while proNGF and p75NTR increased (p < 0.05). Additionally, compared to the sham group, the levels of NGF, proNGF, and p75NTR in lung tissue were elevated in both young and elderly I/R groups of rats (p < 0.05). Moreover, the expression of proNGF and p75NTR in lung tissue was higher in the elderly I/R group than in the young I/R group (p < 0.05). Cerebral ischemia-reperfusion-induced lung injury was associated with increased expression of proNGF and p75NTR, as well as decreased NGF expression in lung tissue. These alterations in NGF, proNGF, and p75NTR may contribute to the susceptibility to age-related lung injury.

Chen H ，Du Q ，Chen J ，Tian Q ，Xu L ，Wang Y ，Gu X ... -  《-》

20(R)-ginsenoside Rg3 protects against focal cerebral ischemia‒reperfusion injury by suppressing autophagy via PI3K/Akt/mTOR signaling pathway.

This study aimed to investigate the effect of 20(R)-ginsenoside Rg3 on autophagy induced by cerebral ischemia‒reperfusion injury (CIRI) in rats and explore its regulation of the PI3K/Akt signaling pathway. Middle cerebral artery occlusion/reperfusion (MCAO/R) in male rats was injected intraperitoneally with 20(R)-ginsenoside Rg3 (5, 10, 20 mg/kg) 12 h before modeling, 2 h after ischemia and 12 h after reperfusion. Neurobehavioral and neuronal morphological changes were detected 24 h after brain I/R. In vitro, the OGD/R-induced injury model is replicated in PC12 cells and different concentrations of 20(R)-ginsenoside Rg3 are administered to observe its effects on cell viability and autophagy and PI3K/Akt/mTOR-related protein expression. Our findings suggest that treatment with 20 mg/kg 20(R)-ginsenoside Rg3 significantly attenuated the neuronal injury, as evidenced by a decreased number of damaged neurons, reduced dissolution of Nissl corpuscles, a fewer autophagosomes, and downregulated expression of Beclin1 and LC3-II/I compared with the MCAO/R group. Furthermore, 20(R)-ginsenoside Rg3 treatment significantly upregulated the expression of p62, p-PI3K, p-AKT, and p-mTOR. In vitro, 20(R)-ginsenoside Rg3 significantly improved the survival rate of cells following OGD/R and markedly attenuated the LY294002 and OGD/R-induced upregulation of Beclin1 and LC3 gene expression. Moreover, 20(R)-ginsenoside Rg3 could rescued the LY294002 and OGD/R-induced downregulation of p62, p-PI3K, p-AKT, and p-mTOR expression. 20(R)-ginsenoside Rg3 attenuates neuronal injury and motor dysfunction following ischemia-reperfusion by inhibiting the activation of autophagy, and its mechanism is related to the upregulation of the PI3K/Akt/mTOR signaling pathway.

Tao D ，Li F ，Zhang X ，Guo H ，Yang R ，Yang Y ，Zhang L ，Shen Z ，Teng J ，Chen P ，He B ... -  《-》