PEDF-34 attenuates neurological deficit and suppresses astrocyte-dependent neuroinflammation by modulating astrocyte polarization via 67LR/JNK/STAT1 signaling pathway after subarachnoid hemorrhage in rats.

BACKGROUND: Reactive astrocytes participate in various pathophysiology after subarachnoid hemorrhage (SAH), including neuroinflammation, glymphatic-lymphatic system dysfunction, brain edema, BBB disruption, and cell death. Astrocytes transform into two new reactive phenotypes with changed morphology, altered gene expression, and secretion profiles, termed detrimental A1 and beneficial A2. This study investigates the effect of 67LR activation by PEDF-34, a PEDF peptide, on neuroinflammation and astrocyte polarization after the experimental SAH. METHODS: A total of 318 male adult Sprague-Dawley rats were used in experiments in vivo, of which 272 rats were subjected to the endovascular perforation model of SAH and 46 rats underwent sham surgery. 67LR agonist (PEDF-34) was administrated intranasally 1 h after SAH. 67LR-specific inhibitor (NSC-47924) and STAT1 transcriptional activator (2-NP) were injected intracerebroventricularly 48 h before SAH. Short- and long-term neurological tests, brain water content, immunostaining, Nissl staining, western blot, and ELISA assay were performed. In experiments in vitro, primary astrocyte culture with hemoglobin (Hb) stimulation was used to mimic SAH. The expression of the PEDF-34/67LR signaling pathway and neuro-inflammatory cytokines were assessed using Western blot, ELISA, and immunohistochemistry assays both in vivo and in vitro. RESULTS: Endogenous PEDF and 67LR expressions were significantly reduced at 6 h after SAH. 67LR was expressed in astrocytes and neurons. Intranasal administration of PEDF-34 significantly reduced brain water content, pro-inflammatory cytokines, and short-term and long-term neurological deficits after SAH. The ratio of p-JNK/JNK and p-STAT1/STAT1 and the expression of CFB and C3 (A1 astrocytes marker), significantly decreased after PEDF-34 treatment, along with fewer expression of TNF-α and IL-1ß at 24 h after SAH. However, 2-NP (STAT1 transcriptional activator) and NSC-47924 (67LR inhibitor) reversed the protective effects of PEDF-34 in vivo and in vitro by promoting A1 astrocyte polarization with increased inflammatory cytokines. CONCLUSION: PEDF-34 activated 67LR, attenuating neuroinflammation and inhibiting astrocyte A1 polarization partly via the JNK/STAT1 pathway, suggesting that PEDF-34 might be a potential treatment for SAH patients.

Deliberately Staged Combined Endovascular Embolization and Subsequent Microsurgery Resection for the Treatment of Cerebral Arteriovenous Malformations.

OBJECTIVE: Complex cerebral arteriovenous malformations (AVMs) require a combined therapy of endovascular embolization and microsurgical resection to eliminate the lesion and maximize neurological protection, while a deliberate time interval might contribute to optimal clinical outcomes. The present study aimed to explore the feasibility of this paradigm. METHODS: All patients who underwent deliberately planned presurgery embolization and microsurgery resection between 2015 and 2023 were reviewed, with baseline data, postoperative complications, and follow-up outcomes recorded. The modified Rankin scale (mRS) was used to evaluate clinical outcomes, with mRS 0-2 defined as good. RESULTS: A total of 30 patients were included in the study (15 were ruptured AVMs). The median Spetzler-Martin grade of baseline AVMs was 3 (interquartile range: 2-3). The median interval between the last embolization and microsurgery was 5 days (interquartile range: 2.25-7). The complete removal rate was 100%, and the overall permanent complication rate was 16.67%. At the last follow-up, 26 patients achieved mRS 0-2, while 28 had improved or unaltered mRS. The last follow-up mRS significantly improved from baseline and discharge (P = 0.0006 and P = 0.006). The last follow-up mRS decreased by 0.65 for each additional day of time interval before the 4.4-day inflection point (ß = -0.65, P = 0.02) in the AVM ruptured cohort. CONCLUSIONS: The deliberately staged combined procedure of embolization and microsurgery might be a safe and efficacious strategy for Spetzler-Martin grade 2-5 AVMs, 4-5 days might be an appropriate staged time interval for ruptured AVMs, although further studies are needed to substantiate these findings.

Endovascular Treatment of Acute Ischemic Stroke Due to Isolated Proximal Posterior Artery Occlusion.

Background: Acute ischemic stroke (AIS) due to isolated proximal posterior cerebral artery (PPCA) occlusion is rare but associated with high morbidity and mortality rates. However, the optimal treatment strategy for patients with AIS caused by PPCA remains unclear. We discuss our single-center experience with endovascular treatment (EVT) in patients with PPCA. Methods: Data from patients with AIS due to PPCA occlusion were retrospectively analyzed. We analyzed procedural details, the degree of reperfusion, functional outcomes, and complications. Functional outcomes were determined using the modified Rankin Scale (mRS) at 90 days, and good outcome was defined as mRS 0-2 at 90 days. Successful reperfusion was defined as modified treatment in cerebral ischemia (mTICI) 2b-3 after endovascular therapy. Safety variables included symptomatic hemorrhage (defined as an increase of four or more points in the National Institute of Health Stroke Scale score), vessel perforation or dissection, and new ischemic stroke in different territories. Results: Seven patients were included in this study. The mean age of the patients was 64 ± 12.4 years. Successful reperfusion was achieved in all seven patients (100%). Good outcomes were achieved at 90 days in 2 patients (28.6%), and favorable outcomes were observed in five patients (71.4%). One patient underwent angioplasty as rescue therapy after three attempts. One patient died because of severe gastrointestinal bleeding 24 h after EVT, which was probably a complication of intravenous alteplase. One patient had an embolism in the basilar artery and achieved complete reperfusion after rescue thrombectomy. Another patient had a complication of vessel dissection in the PPCA and underwent stent implantation as rescue therapy. We observed no recurrence of ischemic stroke or any intracranial hemorrhage on non-contrast computed tomography 24 h after the procedure. Conclusion: EVT may represent an alternative treatment strategy for patients with acute ischemic stroke caused by PPCA.

Time correlation of success recanalization for endovascular recanalization of medically refractory non-acute intracranial arterial occlusions.

Background and purpose: The management of patients with symptomatic non-acute atherosclerotic intracranial artery occlusion (sNAA-ICAO), which is a special subset with high morbidity and a high probability of recurrent serious ischemic events despite standard medical therapy, has been clinically challenging. A number of small-sample clinical studies have discussed endovascular recanalization for sNAA-ICAO and the lack of a uniform standard of operation time. The purpose of this study was to investigate the time correlation of successful recanalization. Methods: From January 2013 to August 2021, 69 consecutive patients who underwent endovascular recanalization for sNAA-ICAO were analyzed retrospectively in the First Affiliated Hospital of Harbin Medical University. The technical success rate, periprocedural complications, and rate of TIA/ischemic stroke during follow-up were evaluated. Results: The overall technical success rate was 73.91% (51/69), and the rate of perioperative complications was 37.68% (26/69). The percentage of patients with perioperative symptoms was 27.53% (19/69). The rate of serious symptomatic perioperative complications was 8.70% (6/69). After adjusting for age, sex, and BMI, the effect of the time from the last symptom to operation on successful recanalization was 0.42 (IQR, 0.20, 0.88, P = 0.021), before the inflection point (51 days). Conclusions: Endovascular recanalization for sNAA-ICAO is technically feasible in reasonably selected patients. The perioperative safety is within the acceptable range. Before 51 days, the last symptoms to operation time, for every 10 days of delay, the probability of successful recanalization is reduced by 57%.