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Objectives: Moderate-to-severe sleep-disordered breathing (SDB) is prevalent in patients with acute ischaemic stroke (AIS) and is associated with an increased risk of unfavourable prognosis. We aimed to develop and validate a reliable scoring system for the early screening of moderate-to-severe SDB in patients with AIS, with the objective of improving the management of those patients at risk., Study Design: We developed and validated a nomogram model based on univariate and multivariate logistic analyses to identify moderate-to-severe SDB in AIS patients. Moderate-to-severe SDB was defined as an apnoea-hypopnoea index (AHI) ≥15. To evaluate the effectiveness of our nomogram, we conducted a comparison with the STOP-Bang questionnaire by analysing the area under the receiver operating characteristic curve., Setting: Large stroke centre in northern Shanghai serving over 4000 inpatients, 100 000 outpatients and emergency visits annually., Participants: We consecutively enrolled 116 patients with AIS from the Shanghai Tenth People's Hospital., Results: Five variables were independently associated with moderate-to-severe SDB in AIS patients: National Institutes of Health Stroke Scale score (OR=1.20; 95% CI 0.98 to 1.47), neck circumference (OR=1.50; 95% CI 1.16 to 1.95), presence of wake-up stroke (OR=21.91; 95% CI 3.08 to 156.05), neuron-specific enolase level (OR=1.27; 95% CI 1.05 to 1.53) and presence of brainstem infarction (OR=4.21; 95% CI 1.23 to 14.40). We developed a nomogram model comprising these five variables. The C-index was 0.872, indicated an optimal agreement between the observed and predicted SDB patients., Conclusions: Our nomogram offers a practical approach for early detection of moderate-to-severe SDB in AIS patients. This tool enables individualised assessment and management, potentially leading to favourable outcomes., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Dimethylarginine dimethylaminohydrolase 1 (DDAH1) protects against cerebral ischemia injury via regulating the level of asymmetric dimethylarginine (ADMA). This study is aimed at exploring the effect of adiponectin resistance on ADMA-induced neuronal loss in ischemic stroke (IS) and the underlying mechanism. DDAH1 knockout (DDAH1 -/- ) and wild-type (DDAH1 +/+ ) rats underwent middle cerebral artery occlusion/reperfusion (MCAO/R). Plasma and brain adiponectin levels and the expressions of adiponectin receptor 1 (APR1), adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 1 (APPL1), adenosine monophosphate-activated protein kinase (AMPK), and phosphorylated AMPK were determined after 24 h, 3 days, and 7 days. Neurological behavior, infarct volume, and adiponectin signaling were evaluated using adiponectin peptide or AdipoRon. The levels of reactive oxygen species (ROS) and Forkhead box O1 (FOXO1) (a transcription factor for APR1) were also assessed. An oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in primary neurons. DDAH1 was overexpressed in neurons, after which FOXO1 expression, ROS production, adiponectin resistance, and cell viability were detected. DDAH1 -/- rats showed no significant difference in adiponectin level in either plasma or brain after MCAO/R in DDAH1 +/+ rats, but downregulated APR1 expression and suppressed adiponectin signaling were observed. AdipoRon, but not adiponectin peptide, attenuated the neurological deficits and adiponectin resistance in DDAH1 -/- rats. ROS accumulation and phosphorylated FOXO1 expression also increased with DDAH1 depletion. Following DDAH1 overexpression, decreased cell viability and inhibited adiponectin signaling induced by OGD/R were alleviated in primary neurons, accompanied by reduced ROS production and phosphorylated FOXO1 expression. Our study elucidated that in IS, DDAH1 protected against adiponectin resistance in IS via the ROS/FOXO1/APR1 pathway., Competing Interests: The authors declare no conflicts of interest regarding the publication of this manuscript., (Copyright © 2022 Yichen Zhao et al.)

Dimethylarginine dimethylamino hydrolase-1 (DDAH-1) is an important regulator of nitric oxide (NO) metabolism that has been implicated in the pathogenesis of cardiovascular diseases. Nevertheless, its role in cerebral ischemia still needs to be elucidated. Herein, we examined the expression of DDAH-1 in the brain of rat by double-label immunofluorescence staining. DDAH-1 knock-out (DDAH-1 -/- ) and wild-type rats underwent middle cerebral artery occlusion/reperfusion (MCAO/R). After 24 h, neurological scores, TTC staining and TUNEL assay were used to evaluate neurological damages. 3 and 7-days infarct outcomes were also shown. Blood-brain-barrier (BBB) permeability was examined via Evans blue extravasation and tight junction (TJ) proteins expression and mRNA levels by western blot and RT-qPCR. The levels of plasma asymmetric dimethylarginine (ADMA), NO and ADMA in brain tissue were also assessed. In addition, supplementation of L-arginine to DDAH-1 -/- rats was used to explore its role in regulating NO. DDAH-1 was abundantly distributed in cerebral cortex and basal nuclei, and mainly expressed in neurons and endothelial cells. DDAH-1 -/- rats showed aggravated neurological damage and BBB disruption, including decrease of TJ proteins expression but indistinguishable mRNA levels after MCAO/R. DDAH-1 depletion and neurological damages were accompanied with increased ADMA levels and decreased NO concentrations. The supplementation with L-arginine partly restored the neurological damages and BBB disruption. To sum up, DDAH-1 revealed to have a protective role in ischemia stroke (IS) and IS-induced leakage of BBB via decreasing ADMA level and possibly via preventing TJ proteins degradation.

Mechanical thrombectomy is not only effective for managing patients with acute ischemic stroke (AIS), but it also enables a valuable histological analysis of thrombi. Previous studies indicated that regulatory T cells (Treg) adoptive transfer might alleviate the hemorrhagic transformation. However, whether Treg in intracranial thrombi correlates with hemorrhagic transformation after mechanical thrombectomy remains unclear. This study mainly analyzed the colocation of Treg markers in serial thrombus sections stained serially for CD4 and CD25 in groups of hemorrhagic or nonhemorrhagic transformation. Second, to investigate whether these immunohistochemical parameters could provide any additional information beyond hemorrhagic transformation, we compared the overlap between Treg markers among other groups, such as functional outcomes, stroke subtypes, and gender. Our results showed that the number of CD4 + CD25 + Treg cells was lower in the hemorrhagic transformation thrombi than in the nonhemorrhagic group ( p < 0.001) but there were no significant differences otherwise. The present finding of CD4 + CD25 + Treg cell reductions in thrombi associated with hemorrhagic transformation provides the histological evidence supporting that thromboinflammation might involve in the pathological process of an acute stroke after mechanical thrombectomy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li Gong et al.)

Dimethylarginine dimethylamino hydrolase-1 (DDAH-1) as an indirect regulator of nitric oxide (NO) metabolism, its role in hypoxic preconditioning (HPC) and ischemic tolerance (IT) of ischemic stroke has still been unknown and needs to be elucidated. Herein, DDAH-1 knock-out (KO) and wild-type (WT) rats underwent HPC and middle cerebral artery occlusion/reperfusion (MCAO/R) model. After 24 h, neurological severity scores, TTC staining and TUNEL assay were used to evaluate neurological damages. To explore the mechanism, the expression of hypoxia inducible factor (HIF-1α) and its target genes were assessed by Western blot and RT-qPCR. NO and ADMA contents were also tested. In addition, supplementation of l-arginine to DDAH-1 KO rats was used to explore the role of DDAH-1 in regulating NO. After HPC the ischemic outcome improved in both KO and WT rats, while KO rats showed attenuated IT exhibiting less expression of HIF-1α and its target genes, lower NO but higher ADMA content. The supplement of l-arginine to KO rats partly alleviated neurological damages accompanied with higher expression of HIF-1α. To sum up, DDAH-1 could regulate the level of NO and enhance IT following HPC and MCAO model via activating the expression of HIF-1α and its target genes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Cerebral ischemia is the most common cause of stroke with high morbidity, disability and mortality. Sirtuin-2 (Sirt2), a vitally important NAD + -dependent deacetylase which has been widely researched in central nervous system diseases, has also been identified as a promising treatment target using its specific inhibitors such as AK-7. In this study, we found that P38 was specifically activated after focal cerebral ischemic injury, and it was also significantly activated after AK-7 administration in a concentration-dependent manner in vitro and in vivo. AK-7 decreased the infarction volume remarkably and promoted the recovery of neurological function efficiently in the mice evaluated by behavior tests. In contrast, pP38 inhibition increased the infarct volume and exacerbated the symptoms of paralysis. Herein, we suggest AK-7 improves the outcome of brain ischemia in dependence on the P38 activation in mice, which may serve as a strategy for the treatment of stroke., (Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.)

White matter lesion (WML) is popular in the patients aged over 65. Brain edema and blood-brain barrier (BBB) dysfunction due to cerebral chronic hypoperfusion (CCH) contributed to WML. Preserving astrocyte polarity is vital for BBB integrity. In our experiment, CCH model is established by bilateral carotid arteries occlusion (2VO). Leukoaraiosis was verified by fiber density stain, and brain edema was evaluated using brain water content measuring. The expressions of agrin and aquaporin-4 (AQP4) were evaluated, as well as the integrity of BBB. Astrocyte polarity was assessed by visualizing the distribution of AQP4 on astrocyte end-feet membranes. The results showed that expression of AQP4 firstly increased and then decreased, as agrin expression decreased gradually. At 3 days after 2VO, AQP4 and agrin displayed the most opposite expression with the former increasing and the latter decreasing; at the same time, brain edema reached high point as well as BBB permeability, and astrocyte polarity was degeneration. In the later phase, brain edema and BBB permeability were getting recovered, but WML was getting more evident. In accordance with that, agrin and AQP4 expression decreased significantly with astrocyte polarity reducing. We speculated that agrin and AQP4 played key roles in development of WML by mediating BBB damage in CCH, and BBB dysfunction due to reduced astrocyte polarity is the starting point of WMH.

Objective: In this study, we aimed to evaluate the safety and efficiency of low dose intra- arterial tirofiban in mechanical thrombectomy of acute ischemic stroke patients to facilitate the reperfusion of distal vessel., Methods: We retrospectively analyzed 54 consecutive acute ischemic patients who underwent mechanical thrombectomy for large-vessel occlusion. Patients were divided into two groups based on whether intra-arterial tirofiban was used during mechanical thrombectomy to facilitate the reperfusion of distal vessel. Patients in Non-tirofiban group (n=28) have received mechanical thrombectomy, while Patients in Tirofiban group (n=26) have received mechanical thrombectomy with a low dose intra-arterial tirofiban. We comparatively analyzed two groups of the bleeding complications, recanalization rate, 24-hour National Institutes of Health Stroke Scale score, functional independence of 90 day and mortality rate., Results: Of 54 patients undergoing mechanical thrombectomy, baseline characteristics did not differ between the Tirofiban group and Non-tirofiban cohort. Symptomatic intracranial hemorrhage rates were not different between Tirofiban group and Non-tirofiban group (11.5 % vs. 14.3%). Total 47 (87.0%) patients have realized successful recanalization, no apparent difference between two groups (85.7% vs. 88.5%, P>0.05). Mean 24-hour National Institutes of Health Stroke Scale score was 9.24±6.85, 9.11±8.13 in the Non-tirofiban group and 9.39±5.31 in the Tirofiban group respectively, P>0.05. Total 20 (35.7%) patients have achieved functional independence (34.6% vs. 39.3%, P>0.05) at 90 days. Patients treated with tirofiban presented lower mortality when compared with those who were not treated with tirofiban without significant difference (10.7% versus 3.8%, P>0.05)., Conclusion: Intra-arterial tirofiban may be safe in mechanical thrombectomy of acute ischemic stroke to facilitate the reperfusion of distal vessel, but has no beneficial effect on prognosis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Post-stroke depression (PSD) seriously affects the rehabilitation of nerve function and quality of life. However, the pathogenesis of PSD is still not clear. This study aimed to investigate the demographic, clinical, and biochemical factors in patients with PSD., Methods: Patients with an acute ischemic stroke, who met the inclusion criteria at Shanghai Tenth People's Hospital from April 2016 to September 2016, were recruited for this study. The stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and the mental state was assessed using Mini-Mental State Examination (MMSE), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) at 1 week of admission. The patients were divided into PSD and non-PSD groups. The demographic and clinical characteristics, as well as the biochemical factors, were compared between the two groups. A logistic regression analysis was performed to identify the risk factors for depression following stroke., Results: A total of 83 patients with acute ischemic stroke were recruited. Of these, 36 (43.4%) developed depression. The multivariate logistic regression analysis indicated that high NIHSS [odds ratio (OR): 1.84, 95% confidence interval (CI): 1.09-3.12, P = 0.023] and high HAMD scores (OR: 2.38, 95% CI: 1.61-3.50, P < 0.001) were independent risk predictors for PSD and so were lower dopamine level (OR: 0.64, 95% CI: 0.45-0.91, P = 0.014), lower 5-hydroxytryptamine level (OR: 0.99, 95% CI: 0.98-1.00, P = 0.046), higher tumor necrosis factor-α level (OR: 1.05, 95% CI: 1.00-1.09, P = 0.044), and lower nerve growth factor level (OR: 0.06, 95% CI: 0.01-0.67, P = 0.022)., Conclusions: The identification of higher NIHSS scores, higher HAMD scores, lower dopamine level, lower 5-hydroxytryptamine level, higher tumor necrosis factor-α level, and lower nerve growth factor level might be useful for clinicians in recognizing and treating depression in patients after a stroke.

Aim: To evaluate the clinical efficacy of Human Urinary kallidinogenase (HUK) in the treatment of acute ischemic stroke (AIS) patients with level 3 hypertension., Methods: In this retrospective study, from January 2015 to June 2016, 150 consecutive AIS patients were registered in our database. Among them, 47 with level 3 hypertension received either HUK treatment (HUK group, 22 cases) or basic treatment (control group, 25 cases). Basic treatment was administrated on all patients. 0.15 PNA unit of HUK injection plus 100 ml saline in intravenous infusion was performed in the HUK group, with once a day for 14 consecutive days. The modified Rankin Scale (mRS) scores in two groups were analyzed 3 months after the treatment., Results: No difference was found in the NIHSS scores, age, gender, and comorbidities between two groups before treatment ( p  >   .05). While after treatment, 3-month mRS score was significantly lower in the HUK group (2.1 ± 1.4 vs. 3.1 ± 1.3, p  =   .012) and good recovery rate (3-month mRS score ≤2) in the HUK group was significantly higher than that in the control group ( p  <   .05)., Conclusion: HUK is able to promote long-term recovery for AIS patients with level 3 hypertension remarkably.

Our previous study has shown that PTEN-induced novel kinase 1 (PINK1) knocking down significantly induced mitochondrial fragmentation. Although PINK1 is proved to be associated with autosomal recessive parkinsonism and its function in this chronic pathological process is widely studied, its role in acute energy crisis such as ischemic stroke is poorly known. In this study by employing an oxygen-glucose deprivation (OGD) neuronal model, we explored the function of PINK1 in cerebral ischemia. Human PINK1, two PINK1 mutants W437X and K219M, or Pink1 shRNA were transduced before OGD using lentiviral delivery. Our results showed that over-expression of wild-type PINK1 significantly ameliorated OGD induced cell death and energy disturbance including reduced ATP generation and collapse of mitochondrial membrane potential. PINK1 over-expression also reversed OGD increased mitochondrial fragmentation, and suppressed the translocation of the mitochondrial fission protein dynamin-related protein 1 (Drp1) from the cytosol to the mitochondria. Transduction of the mutant PINK1 failed to provide any protective effect, while knockdown of Pink1 significantly increased the severity of OGD-induced neuronal damage. Importantly, inhibition of Drp1 reversed the effects of knocking down Pink1 on neuronal death and ATP production in response to OGD. This study demonstrates that PINK1 prevents ischemic damage in neurons by attenuating mitochondrial translocation of Drp1, which maintains mitochondrial function and inhibits ischemia-induced mitochondrial fission. These novel findings implicate a pivotal role of PINK1 regulated mitochondrial dynamics in the pathology of ischemic stroke. In this study by employing an oxygen-glucose deprivation (OGD) neuronal model, we explored the function of PINK1 in cerebral ischemia. We indicated that PINK1 significantly ameliorated OGD induced cell death and energy disturbance including reduced ATP generation and collapse of mitochondrial membrane potential by attenuating mitochondrial translocation of Drp1, which maintains mitochondrial function and inhibits ischemia-induced mitochondrial fission., (© 2013 International Society for Neurochemistry.)

Objective: The aim of this study was to investigate the protective effect of dl-3-n-butylphthalide (NBP) on brain damage in streptozotocin (STZ)-induced diabetic mice subjected to cerebral ischemia., Methods: we pretreated diabetic mice with NBP orally for 4 weeks prior and 2 days after transient common carotid artery occlusion (CCAO) operation. Immunohistochemistry and transmission electron microscopy were performed to investigate the neuronal loss, astrocytes activation, amyloid-beta (Abeta) protein expression, and autophagy activation., Results: The results showed that diabetes increased stroke-induced neuronal loss, astrocytes activation, Abeta generation, and autophagy activity, while NBP administration attenuated these changes. Immunofluorescence double staining of Abeta with autophagosome-specific antibody LC3 showed that most elevated Abeta(+) signal was co-localized with LC3(+) signal., Conclusion: Our finding suggests that NBP attenuates Abeta generation promoted by diabetes in ischemia might act through inhibiting abnormally activated neuronal autophagy. Therefore, treatment with NBP to modulate autophagy might provide a novel therapeutic strategy for diabetes by preventing ischemic brain damage and depressing the risk of post-stroke dementia.