Proteomics-Guided Study on Buyang Huanwu Decoction for Its Neuroprotective and Neurogenic Mechanisms for Transient Ischemic Stroke: Involvements of EGFR/PI3K/Akt/Bad/14-3-3 and Jak2/Stat3/Cyclin D1 Signaling Cascades.

Buyang Huanwu Decoction (BHD), a classic traditional Chinese medicine (TCM) formula, has been used for recovering neurological dysfunctions and treating post-stroke disability in China for 200 years. In the present study, we investigated the effects of BHD on inhibiting neuronal apoptosis, promoting proliferation and differentiation of neural stem cells (NSCs) and neurite formation and enhancing learning and memory functional recovery in an experimental rat ischemic stroke model. BHD significantly reduced infarct volume and decreased cell apoptosis in the ischemic brain. BHD enhanced neuronal cell viability in vitro. BHD dose-dependently promoted the proliferation of NSCs in ischemic rat brains in vivo. Moreover, BHD promoted neuronal and astrocyte differentiation in primary cultured NSCs in vitro. Water maze test revealed that BHD promoted the recovery of learning function but not memory functions in the transient ischemic rats. We then investigated the changes of the cellular signaling molecules by using two-dimension (2D) gel electrophoresis and focused on the PI3K/Akt/Bad and Jak2/Stat3/cyclin D1signaling pathway to uncover its underlying mechanisms for its neuroprotective and neurogenetic effects. BHD significantly upregulated the expression of p-PI3K, p-Akt, and p-Bad as well as the expression of p-Jak, p-Stat3, and cyclin D1 in vitro and in vivo. In addition, BHD upregulated Hes1 and downregulated cav-1 in vitro and in vivo. Taken together, these results suggest that BHD has neuroprotective effects and neurogenesis-promoting effects via activating PI3K/Akt/Bad and Jak2/Stat3/Cyclin D1 signaling pathways. Graphical Abstract Buyang Huanwu Decoction (BHD) activates the PI3K-AKT-BAD pathway in the ischemic brain for neuroprotection. BHD also activates JAK2/STAT3/Cyclin D1 signaling cascades for promoting neurogenesis in the hippocampus of post-ischemic brains. Moreover, BHD inhibits the expression of caveolin-1 and increases the expression of HES1 for promoting neuronal differentiation. The neuroprotective and neurogenesis-promoting effects in the hippocampus of post-ischemic brains promote learning ability.

Neuroprotective effect of the ethanol extract of Artemisia capillaris on transient forebrain ischemia in mice via nicotinic cholinergic receptor.

Artemisia capillaris Thunberg is a medicinal plant used as a traditional medicine in many cultures. It is an effective remedy for liver problems including hepatitis. Recent pharmacological reports have indicated that Artemisia species can exert various neurological effects. Previously, we reported a memory-enhancing effect of Artemisia species. However, the mechanisms underlying the neuroprotective effect of A. capillaris (AC) are still unknown. In the present study, we investigated the effect of an ethanol extract of AC on ischemic brain injury in a mouse model of transient forebrain ischemia. The mice were treated with AC for seven days, beginning one day before induction of transient forebrain ischemia. Behavioral deficits were investigated using the Y-maze. Nissl and Fluoro-jade B staining were used to indicate the site of injury. To determine the underlying mechanisms for the drug, we measured acetylcholinesterase activity. AC (200 mg·kg-1) treatment reduced transient forebrain ischemia-induced neuronal cell death in the hippocampal CA1 region. The AC-treated group also showed significant amelioration in the spontaneous alternation of the Y-maze test performance, compared to that in the untreated transient forebrain ischemia group. Moreover, AC treatment showed a concentration-dependent inhibitory effect on acetylcholinesterase activity in vitro. Finally, the effect of AC on forebrain ischemia was blocked by mecamylamine, a nonselective nicotinic acetylcholine receptor antagonist. Our results suggested that in a model of forebrain ischemia, AC protected against neuronal death through the activation of nicotinic acetylcholine receptors.

Hospital recruitment for a pragmatic cluster-randomized clinical trial: Lessons learned from the COMPASS study.

BACKGROUND: Pragmatic randomized clinical trials are essential to determine the effectiveness of interventions in "real-world" clinical practice. These trials frequently use a cluster-randomized methodology, with randomization at the site level. Despite policymakers' increased interest in supporting pragmatic randomized clinical trials, no studies to date have reported on the unique recruitment challenges faced by cluster-randomized pragmatic trials. We investigated key challenges and successful strategies for hospital recruitment in the Comprehensive Post-Acute Stroke Services (COMPASS) study. METHODS: The COMPASS study is designed to compare the effectiveness of the COMPASS model versus usual care in improving functional outcomes, reducing the numbers of hospital readmissions, and reducing caregiver strain for patients discharged home after stroke or transient ischemic attack. This model integrates early supported discharge planning with transitional care management, including nurse-led follow-up phone calls after 2, 30, and 60 days and an in-person clinic visit at 7-14 days involving a functional assessment and neurological examination. We present descriptive statistics of the characteristics of successfully recruited hospitals compared with all eligible hospitals, reasons for non-participation, and effective recruitment strategies. RESULTS: We successfully recruited 41 (43%) of 95 eligible North Carolina hospitals. Leading, non-exclusive reasons for non-participation included: insufficient staff or financial resources (n = 33, 61%), lack of health system support (n = 16, 30%), and lack of support of individual decision-makers (n = 11, 20%). Successful recruitment strategies included: building and nurturing relationships, engaging team members and community partners with a diverse skill mix, identifying gatekeepers, finding mutually beneficial solutions, having a central institutional review board, sharing published pilot data, and integrating contracts and review board administrators. CONCLUSIONS: Although we incorporated strategies based on the best available evidence at the outset of the study, hospital recruitment required three times as much time and considerably more staff than anticipated. To reach our goal, we tailored strategies to individuals, hospitals, and health systems. Successful recruitment of a sufficient number and representative mix of hospitals requires considerable preparation, planning, and flexibility. Strategies presented here may assist future trial organizers in implementing cluster-randomized pragmatic trials. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02588664 . Registered on 23 October 2015.

Efficacy of a Chronic Care-Based Intervention on Secondary Stroke Prevention Among Vulnerable Stroke Survivors: A Randomized Controlled Trial.

BACKGROUND: Disparities of care among stroke survivors are well documented. Effective interventions to improve recurrent stroke preventative care in vulnerable populations are lacking. METHODS AND RESULTS: In a randomized controlled trial, we tested the efficacy of components of a chronic care model-based intervention versus usual care among 404 subjects having an ischemic stroke or transient ischemic attack within 90 days of enrollment and receiving care within the Los Angeles public healthcare system. Subjects had baseline systolic blood pressure (SBP) ≥120 mm Hg. The intervention included a nurse practitioner/physician assistant care manager, group clinics, self-management support, report cards, decision support, and ongoing care coordination. Outcomes were collected at 3, 8, and 12 months, analyzed as intention-to-treat, and used repeated-measures mixed-effects models. Change in SBP was the primary outcome. Low-density lipoprotein reduction, antithrombotic medication use, smoking cessation, and physical activity were secondary outcomes. Average age was 57 years; 18% were of black race; 69% were of Hispanic ethnicity. Mean baseline SBP was 150 mm Hg in both arms. SBP decreased to 17 mm Hg in the intervention arm and 14 mm Hg in the usual care arm; the between-arm difference was not significant (-3.6 mm Hg; 95% confidence interval, -9.2 to 2.2). Among secondary outcomes, the only significant difference was that persons in the intervention arm were more likely to lower their low-density lipoprotein <100 md/dL (2.0 odds ratio; 95% confidence interval, 1.1-3.5). CONCLUSIONS: This intervention did not improve SBP control beyond that attained in usual care among vulnerable stroke survivors. A community-centered component could strengthen the intervention impact. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT00861081.

[Animal model analysis on transient ischemic attack based on clinical symptom characteristics of Chinese and Western medicine].

Based on the clinical symptom characteristics of transient ischemic attack in Chinese and Western medicines, the existing models of transient ischemic attack were summarized and analyzed. Then the advantages and disadvantages of each model, the diagnostic criteria of traditional Chinese and Western medicine and clinical symptoms compliance were analyzed to put forward the evaluation method and improvement method of the corresponding animal models. It was found that there were many modeling methods of transient ischemic attack, but they can not reflect the transience, reversibility, recurrence and other typical characteristics of the disease, with significant differences with clinical symptoms. Moreover, there is lack of reasonable quantitative criteria for the success of the animal model. By combining the existing single factor animal models, a composite animal model that was more closely related to the clinical symptoms of transient ischemic attack was established to replicate an animal model that was more compatible with the characteristics of clinical symptoms. It is the future development directions of the transient ischemic attack animal models to establish reasonable quantitative standards, reflect the causes of Chinese and Western medicine symptoms and improving a series of systematic and complete model evaluation methods.

Oral anticoagulant persistence in patients with non-valvular atrial fibrillation: A cohort study using primary care data in Germany.

This study examined characteristics and treatment persistence among patients prescribed oral anticoagulants (OACs) for stroke prevention in non-valvular atrial fibrillation (NVAF). We identified 15,244 patients (51.8% male, 72.7% aged ≥70) with NVAF and no prior OAC therapy who were prescribed apixaban (n = 1,303), rivaroxaban (n = 5,742), dabigatran (n = 1,622) or vitamin-K antagonists (VKAs, n = 6,577) between 1-Dec-2012 and 31-Oct-2014 in German primary care (IMS® Disease Analyzer). We compared OAC persistence using Cox regression over patients' entire follow-up and using a data-driven time-partitioned approach (before/after 100 days) to handle non-proportional hazards. History of stroke risk factors (stroke/transient ischaemic attack [TIA] 15.2%; thromboembolism 14.1%; hypertension 84.3%) and high bleeding risk (HAS-BLED score≥3 68.4%) was common. Apixaban-prescribed patients had more frequent history of stroke/TIA (19.7%) and high bleeding risk (72.6%) than other OACs. 12-month persistence rates were: VKA 57.5% (95% confidence interval (CI) 56.0-59.0%), rivaroxaban 56.6% (54.9-58.2%), dabigatran 50.1% (47.2-53.1%), apixaban 62.9% (58.8-67.0%). Over entire follow-up, compared to VKA, non-persistence was similar with apixaban (adjusted hazard ratio 1.08, 95% CI 0.95-1.24) but higher with rivaroxaban (1.21, 1.14-1.29) and dabigatran (1.53, 1.40-1.68). Using post-hoc time-partitioned approach: in first 100 days, non-persistence was higher with apixaban (1.37, 1.17-1.59), rivaroxaban (1.41, 1.30-1.53) and dabigatran (1.91, 1.70-2.14) compared to VKA. Compared to apixaban, rivaroxaban non-persistence was similar (1.03, 0.89-1.20), dabigatran was higher (1.39, 1.17-1.66). After 100 days, apixaban non-persistence was lower than VKA (0.66, 0.52-0.85); rivaroxaban (0.97, 0.87-1.07) and dabigatran (1.10, 0.95-1.28) were similar to VKA. Furthermore, rivaroxaban (1.46, 1.13-1.88) and dabigatran (1.67, 1.26-2.19) non-persistence was higher than apixaban. This study describes real-world observations on OAC use, particularly early apixaban use following approval for NVAF, in Germany. We identified potential differential OAC prescribing and higher persistence with apixaban than other OACs after 100 days' treatment. Larger studies are needed with longer follow-up to establish long-term patterns.

Neuroprotective effects of Ilexonin A following transient focal cerebral ischemia in rats.

Ilexonin A is a compound isolated from the root of a plant commonly used in traditional Chinese medicine. The aim of the present study was to investigate the possible protective mechanism of Ilexonin A in rats subjected to occlusion of the middle cerebral artery (MCAO). Transient focal cerebral ischemia was induced by 2 h of MCAO, followed by reperfusion. Ilexonin A at doses of 20, 40 and 80 mg/kg were administered via intraperitoneal injection immediately following ischemia/reperfusion. The expression levels of glial fibrillary acidic protein (GFAP), ionized calcium­binding adapter molecule­1 (Iba­1), vascular endothelial growth factor (VEGF), fetal liver kinase­1 (Flk­1) and Nestin were examined using immunostaining and Western blot analysis of the peri­infarct region following ischemia/reperfusion. Ilexonin A significantly decreased the infarct volume and improved neurological deficits in a dose­dependent manner. The expression levels of VEGF, Flk­1 and Nestin were significantly increased in the rats treated with Ilexonin A, compared with the rats administered with saline. Following treatment with Ilexonin A, a higher number of GFAP­positive astrocytes were found in the Ilexonin A­treated rats at 1, 3 and 7 days, compared with the rats exposed to ischemia only, however, there were fewer astrocytes at 14 days, compared with the ischemia group. Ilexonin A significantly decreased the protein expression of Iba­1. The results of the present study suggested that the protective effects of Ilexonin A were associated with revascularization, neuronal regeneration, and the regulation of astrocyte and microglia cell activation.

Pathological laughter as prodromal manifestation of transient ischemic attacks--case report and brief review.

BACKGROUND: Based on a case report, the authors reviewed the data about involuntary emotional expression disorder (IEED). IEED includes the syndromes of pathological laughing and crying (PLC) and emotional lability (EL). PLC is a rare disorder of emotional expression characterized by relatively uncontrollable episodes of laughter and crying or both that do not have an apparent motivating stimulus. CASE PRESENTATION: Authors report the case of a 59-year-old man who presented with recurrent episodes of PLC of approximately 2 min duration, consisting of accelerated breathing, emission of guttural, snoring sounds, frowning of the eyebrows, followed by laughter accompanied by motor restlessness of all four limbs. PLC episodes preceded left carotid transient ischemic attacks (TIA's) manifested by reversible aphasia and right hemiparesis. Electroencephalography performed during PLC episodes revealed no spike-wave activity. Brain magnetic resonance imaging showed lacunar infarcts in the left lenticulo-capsulo-thalamic area and multiple round lesions in the cortical-subcortical and in the deep white matter of frontal-parietal-occipital lobes bilaterally, with T2 hyperintensity, T1 isointensity and no diffusion changes. The episodes were interpreted as transient ischemic attacks although gelastic seizures could not be excluded. The etiological investigations revealed unstable plaques on the left carotid artery bulb and the aortic arch and a degenerative mitral valve stenosis. The patient was treated first with antiplatelet therapy and antiepileptic drugs but PLC stopped only after anticoagulation was started. During follow-up the patient continued to have left carotid and vertebrobasilar TIA's being on oral anticoagulation. The patient became asymptomatic only after mitral valve replacement was performed. CONCLUSIONS: This case illustrates the difficulty distinguishing between gelastic epilepsy and TIA's in cases of PLC episodes and discuss the neuroanatomic bases and pathophysiology of this rare condition.

Anti-inflammatory effects of Gualou Guizhi decoction in transient focal cerebral ischemic brains. [Corrected].

The aim of the present study was to explore the neuroprotective effects of Gualou Guizhi decoction (GLGZD) in a rat model of middle cerebral artery occlusion (MCAO). Sprague-Dawley rats were divided into three groups: Sham (no MCAO), MCAO (MCAO with no GLGZD treatment) and GLGZD (MCAO with GLGZD treatment). Rats in the MCAO and GLGZD groups were subjected to permanent occlusion of the left middle cerebral artery. Neurological function and infarct volume were measured. Microglial activation and inflammatory cell accumulation were measured using immunohistochemistry. mRNA and protein expression of inflammatory mediators were examined using reverse transcription-quantitative polymerase chain reaction and an enzyme-linked immunosorbent assay. The expression of proteins associated with the nuclear factor κ-B (NF-κB) inflammation signaling pathway was analyzed using western blotting. The results of the present study suggested that infarct size was significantly reduced and neurological behavior function was improved in rats with MCAO treated with GLGZD compared with rats in the MCAO group. Amoeboid microglial expansion and inflammatory cell migration were observed in the infarcted areas of rats in the GLGZD group and were not identified in those of the MCAO group. Target mRNA and protein levels, and inflammatory cell infiltration were significantly reduced in the GLGZD group compared with the MCAO model group. Notably, GLGZD treatment induced neuroprotective effects, reducing inflammation and inhibiting NF-κB signaling compared with the MCAO group. Therefore, GLGZD may exhibit anti-inflammatory effects against ischemia-reperfusion brain injury and may be a therapeutic target for ischemic stroke.

Evaluating the translational potential of progesterone treatment following transient cerebral ischaemia in male mice.

BACKGROUND: Progesterone is neuroprotective in numerous preclinical CNS injury models including cerebral ischaemia. The aim of this study was two-fold; firstly, we aimed to determine whether progesterone delivery via osmotic mini-pump would confer neuroprotective effects and whether such neuroprotection could be produced in co-morbid animals. RESULTS: Animals underwent transient middle cerebral artery occlusion. At the onset of reperfusion, mice were injected intraperitoneally with progesterone (8 mg/kg in dimethylsulfoxide). Adult and aged C57 Bl/6 mice were dosed additionally with subcutaneous infusion (1.0 µl/h of a 50 mg/ml progesterone solution) via implanted osmotic minipumps. Mice were allowed to survive for up to 7 days post-ischaemia and assessed for general well-being (mass loss and survival), neurological score, foot fault and t-maze performance. Progesterone reduced neurological deficit [F(1,2) = 5.38, P = 0.027] and number of contralateral foot-faults [F(1,2) = 7.36, P = 0.0108] in adult, but not aged animals, following ischaemia. In hypertensive animals, progesterone treatment lowered neurological deficit [F(1,6) = 18.31, P = 0.0001], reduced contralateral/ipsilateral alternation ratio % [F(1,2) = 17.05, P = 0.0006] and time taken to complete trials [F(1,2) = 15.92, P = 0.0009] for t-maze. CONCLUSION: Post-ischemic progesterone administration via mini-pump delivery is effective in conferring functional improvement in a transient MCAO model in adult mice. Preliminary data suggests such a treatment regimen was not effective in producing a protective effect in aged mice. However, in hypertensive mice, who received post-ischemic progesterone intraperitoneally at the onset of reperfusion had better functional outcomes than control hypertensive mice.

KB-R7943, an inhibitor of the reverse Na(+)/Ca(2+) exchanger, does not modify secondary pathology in the thalamus following focal cerebral stroke in rats.

Remote areas connected to cortical infarcts, such as the thalamus, are affected by stroke due to delayed retrograde degeneration of afferent connections. This is temporally associated with the accumulation of ß-amyloid (Aß) and calcium. Here we tested a hypothesis that prevention of excessive Ca(2+) influx into the axoplasm via the reverse Na(+)/Ca(2+) exchanger (NCX) would provide axonal protection and eventually lessen the Aß and calcium load in the thalamus. We found that chronic treatment with a specific inhibitor of the reverse NCX, KB-R7943 (30mg/kg once daily, 27 days) after middle cerebral artery occlusion did not prevent atypical secondary pathology in the thalamus or improve functional outcome. The present data do not support a role for reverse NCX activity in the complex pathology within the thalamus after cerebral ischemia.

Effects of delayed puerarin treatment in long-term neurological outcomes of focal ischemic stroke in rats.

OBJECTIVE: The present study aimed at investigate the therapeutic effects of delayed puerarin treatment in neurological outcomes after middle cerebral artery occlusion (MCAO) in rats. MATERIALS AND METHODS: Male Wistar rats were subjected to MCAO for 120 min followed by reperfusion for 14 days. Puerarin (0, 50, 100, 200 mg/kg, intra-peritoneally) was administered at 24 h after stroke onset and repeated daily for 14 days. Neurological deficits were evaluated at 1, 4, 7, 14 days after stroke. Brain infarct volume and peri-infarct context vessel density were examined at 14 days after stroke. RESULTS: Puerarin significantly improved neurological functions up to 14 days after stroke and decreased the infarct volume with doses of 50 mg/kg and 100 mg/kg compared with saline controls. Puerarin treatment also significantly increased peri-infarct context vessel density at 14 days after stroke. CONCLUSIONS: Delayed treatment of puerarin initiated at 24 h after stroke is beneficial with improved long-term neurological outcomes and reduced infarction volume in focal ischemic stroke in rats. Enhanced vascular remodeling by puerarin might at least partially contribute to its beneficial effects.

The neuroprotective effects of isoflurane preconditioning in a murine transient global cerebral ischemia-reperfusion model: the role of the Notch signaling pathway.

Inhalational anesthetic preconditioning can induce neuroprotective effects, and the notch signaling pathway plays an important role in neural progenitor cell differentiation and the inflammatory response after central nervous system injury. This study evaluated whether the neuroprotective effect of isoflurane preconditioning is mediated by the activation of the notch signaling pathway. Mice were divided into two groups consisting of those that did or did not receive preconditioning with isoflurane. The expression levels of notch-1, notch intracellular domain (NICD), and hairy and enhancer of split (HES-1) were measured in mice subjected to transient global cerebral ischemia-reperfusion injury. The notch signaling inhibitor DAPT and conditional notch-RBP-J knockout mice were used to investigate the mechanisms of isoflurane preconditioning-induced neuroprotection. Immunohistochemical staining, real-time polymerase chain reaction assays, and Western blotting were performed. Isoflurane preconditioning induced neuroprotection against global cerebral ischemia. Preconditioning up-regulated the expression of notch-1, HES-1, and NICD after ischemic-reperfusion. However, these molecules were down-regulated at 72 h after ischemic-reperfusion. The inhibition of notch signaling activity by DAPT significantly attenuated the isoflurane preconditioning-induced neuroprotection, and similar results were obtained using notch knockout mice. Our results demonstrate that the neuroprotective effects of isoflurane preconditioning are mediated by the pre-activation of the notch signaling pathway.

Neuroprotective effect of 20(R)-ginsenoside Rg(3) against transient focal cerebral ischemia in rats.

Gensenosides, the active ingredients of Chinese herbal medicine Panax ginseng, have a wide spectrum of medical effects, such as anti-tumorigenic, angiosuppressive, adaptogenic, and anti-fatigue activities. In the present study, we have investigated the neuroprotective effect of 20(R)-ginsenoside Rg(3) (20(R)-Rg(3)) against transient focal cerebral ischemia in male Sprague-Dawley (SD) rats. The middle cerebral artery was occluded for 2h in rats and then reperfused for 24h. The behavioral disturbance was evaluated according to neurological deficit scores, and the infarct volumes were evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) staining; in addition, ischemia-mediated apoptosis was examined using the method of terminal deoxynucleotidyl transferase (TdT)-mediated d-UTP nick end labeling (TUNEL). The expressions of calpain I and caspase-3 mRNA in hippocampal CA1 region were further assayed using in situ hybridization, in order to clarify the neuroprotective mechanism of 20(R)-Rg(3). 20(R)-Rg(3) at the doses of 10 and 20mgkg(-1) i.p., but not 5mgkg(-1), showed significant neuroprotective effect in rats against focal cerebral ischemic injury by markedly reducing cerebral infarct volumes and degrading infarct rate of TTC-stained coronal brain sections, and improving behavior of the animals. Our results also suggested that 20(R)-Rg(3) (10 and 20mgkg(-1)) could significantly suppress the expressions of calpain I and caspase-3 mRNA. These results indicated that 20(R)-Rg(3) attenuates the neuronal apoptosis caused by cerebral ischemia-reperfusion injury and its neuprotective effect may be involved in the downregulation of calpain I and caspase-3.

Improvement of oxygen supply by an artificial carrier in combination with normobaric oxygenation decreases the volume of tissue hypoxia and tissue damage from transient focal cerebral ischemia.

Tissue hypoxia may play an important role in the development of ischemic brain damage. In the present study we investigated in a rat model of transient focal brain ischemia the neuroprotective effects of increasing the blood oxygen transport capacity by applying a semifluorinated alkane (SFA)-containing emulsion together with normobaric hyperoxygenation (NBO). The spread of tissue hypoxia was studied using pimonidazole given prior to filament-induced middle cerebral artery occlusion (MCAO, 2 h). Treatment consisted of intravenous injection of saline or the SFA-containing emulsion (0.5 or 1.0 ml/100g body weight; [SFA(0.5) or SFA(1.0)]) either upon establishing MCAO (early treatment) or after filament removal (delayed treatment). After injection NBO was administered for 8 h (early treatment) or 6 h (delayed treatment). Experiments were terminated 8 or 24 h after MCAO. In serial brain sections tissue hypoxia and irreversible cell damage were quantitatively determined. Furthermore, we studied hypoxia-related gene expression (VEGF, flt-1). Early treatment significantly (p<0.05) reduced the volumes of tissue damage (8 h after MCAO: SFA(1.0), 57±34 mm³; controls, 217±70 mm³; 24 h after MCAO: SFA(1.0), 189±82 mm³; controls, 317±60 mm³) and of P-Add immunoreactivity (8 h after MCAO: SFA(1.0), 261±37 mm³; controls, 339±26 mm³; 24h after MCAO: SFA(1.0), 274±47 mm³; controls, 364±46 mm³). Delayed treatment was comparably successful. The volume of the hypoxic penumbra was not decreased by the treatment. Similarly, VEGF and flt-1 mRNA levels did not differ between the experimental groups. From these data we conclude that increasing the blood oxygen transport capacity in the plasma compartment provides a neuroprotective effect by alleviating the severity of hypoxia to a level sufficient to prevent cells from transition into irreversible damage.

Neuroprotective effects of Eleutherococcus senticosus bark on transient global cerebral ischemia in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Eleutherococcus senticosus Maxim., classified into the family of Araliaceae, is used in a variety of diseases in traditional Korean medicine including ischemic heart disease. AIM OF THE STUDY: To determine the neuroprotective effects of Eleutherococcus senticosus on global cerebral ischemia. MATERIALS AND METHODS: A four-vessel occlusion (4-VO) rat model was used to evaluate the potential protective effects against transient global cerebral ischemia ethanol extracts of Eleutherococcus senticosus was orally administered at doses of 3, 30, and 300 mg/kg twice at times of 0 and 90 min after reperfusion. The effects on memory deficit were investigated by using a Y-maze neurobehavioral test after brain ischemia, and the effects on hippocampal neuronal damage were measured 7 days after ischemia. The expressions of glial fibrillary acid protein (GFAP), CD11b antibody (OX-42), and cyclooxygenase-2 (COX-2) were investigated by immunohistochemistry. RESULTS: Oral administration of Eleutherococcus seticosus at 30, 100 and 300 mg/kg significantly reduced hippocampal CA1 neuronal death by 3.5%, 25.9% and 53.1%, respectively, compared with a vehicle-treated group. Oral administration of Eleutherococcus senticosus at 300 mg/kg inhibited 81.9% of the decrease in spontaneous alternation induced by 4-VOin the Y-maze test, and also attenuated ischemia-induced activation of COX-2, GFAP and OX-42 in the hippocampal CA1 region. CONCLUSION: Eleutherococcus senticosus protects delayed neuronal death in the CA1 region of the hippocampus against global cerebral ischemia in rats with the recovery of spatial memory, which can be considered as the normal functioning of the hippocampus. Regarding the immunohistochemical study, the effect of Eleutherococcus senticosus may be attributable to its anti-inflammatory properties through the inhibition of COX-2 expression, microglia and astrocyte expression.

Effects of hyperbaric oxygenation on oxidative stress in acute transient focal cerebral ischemic rats.

The aim of this study was to investigate the effects of hyperbaric oxygenation (HBO) after brain ischemia. Middle cerebral artery occlusion (MCAO) procedure was used to induce the brain ischemia. Rats were assigned to control or HBO group after brain ischemia. In order to examine the role of glutathione after HBO treatment, another group of brain ischemic rats were included to receive the glutathione synthesis inhibitor and HBO treatment. HBO was administered at a pressure of 3 atmospheres absolute for 1 h with 100% oxygen, starting at 3 h post brain ischemia in HBO groups. Animals in control group were placed in their home cage and exposed to normobaric room air. The infarct volume (IV), activation of astrocyte, and level of total glutathione and lipid peroxidation (LP) were assessed 24 h post-reperfusion. Significant reduction in IV was noted in HBO group when compared with control group. The activation of astrocyte was significantly increased in the right cerebral cortex and right striatum in the HBO group when compared with those of the control group. The glutathione level was higher with lower LP level in right cortex and right striatum after HBO as compared with those of the control. However, such effects of HBO treatment were markedly reduced by glutathione synthesis inhibitor administration. These results show that inhibiting glutathione synthesis dramatically reduces the effectiveness of HBO in acute transient focal cerebral ischemia.

Kainate postconditioning restores LTP in ischemic hippocampal CA1: onset-dependent second pathophysiological stress.

Postconditioning can be induced by a broad range of stimuli within minutes to days after an ischemic cerebral insult. A special form is elicited by pharmacological intervention called second pathophysiological stress. The present study aimed to evaluate the effects of low-dose (5 mg/kg) kainate postconditioning with onsets 0, 24 and 48 h after the ischemic insult on the hippocampal synaptic plasticity in a 2-vessel occlusion model in rat. The hippocampal function was tested by LTP measurements of Schaffer collateral-CA1 pyramidal cell synapses in acute slices and the changes in density of Golgi-Cox-stained apical dendritic spines. Postconditioning 0 and 24 h after ischemia was not protective, whereas 48-h-onset postconditioning resulted in the reappearance of a normal spine density (>100,000 spines) 3 days after ischemia, in parallel with the long-term restoration of the damaged LTP function. Similar, but somewhat less effects were observed after 10 days. Our data clearly demonstrate the onset dependence of postconditioning elicited by a subconvulsant dose of kainate treatment in global ischemia, with restoration of the structural plasticity and hippocampal function.

Extract from Terminalia chebula seeds protect against experimental ischemic neuronal damage via maintaining SODs and BDNF levels.

The fruit of Terminalia chebula Retz has been used as a traditional medicine in Asia and contains tannic acid, chebulagic acid, chebulinic acid and corilagin. Extract from T. chebula seeds (TCE) has various biological functions. We observed the neuroprotective effects of TCE against ischemic damage in the hippocampal C1 region (CA1) of the gerbil that had received oral administrations of TCE (100 mg/kg) once a day for 7 days before the induction of transient cerebral ischemia. In the TCE-treated ischemia group, neuronal neuclei (a marker for neurons)-positive neurons were distinctively abundant (62% of the sham group) in the CA1 4 days after ischemia-reperfusion (I-R) compared to those (12.2% of the sham group) in the vehicle-treated ischemia group. Four days after I-R TCE treatment markedly decreased the activation of astrocytes and microglia in the ischemic CA1 compared with the vehicle-treated ischemia group. In addition, immunoreactivities of Cu, Zn-superoxide dismutase (SOD1), Mn-superoxide dismutase (SOD2) and brain-derived neurotrophic factor (BDNF) in the CA1 of the TCE-treated ischemia group were much higher than those in the vehicle-ischemia group 4 days after I-R. Protein levels of SOD1, SOD2 and BDNF in the TCE-treated ischemia group were also much higher than those in the vehicle-ischemia group 4 days after I-R. These results indicate that the repeated supplement of TCE protected neurons from ischemic damage induced by transient cerebral ischemia by maintaining SODs and BDNF levels as well as decreasing glial activation.

Ginsenoside Rd attenuates mitochondrial dysfunction and sequential apoptosis after transient focal ischemia.

We previously found that ginsenoside Rd (Rd), one of the major active ingredients in Panax ginseng, protects neuronal cells from hydrogen peroxide and oxygen-glucose deprivation, an in vitro model of cerebral ischemia. In this study, we examined the protective effects of Rd in an animal model of focal cerebral ischemia. Rats administered with Rd or vehicle were subjected to transient middle cerebral artery occlusion (MCAO). Rd (50 mg/kg) significantly reduced the infarct volume by 52.8%. This reduction of injury volume was associated with an improvement in neurological function and was sustained for at least 2 weeks after the induction of ischemia. To evaluate the underlying mechanisms of Rd against stroke, brain tissues were assayed for mitochondrial enzyme activities, mitochondrial membrane potential (MMP), production of reactive oxygen species (ROS), energy metabolites, and apoptosis. Rd markedly protected mitochondria as indicated by preserved respiratory chain complex activities and aconitase activity, lowered mitochondrial hydrogen peroxide production, and hyperpolarized MMP. Microdialysis results illustrated that Rd significantly decreased the accumulation of lactate, the end product of anaerobic glycolysis, and increased pyruvate, the end product of aerobic glycolysis, hence inducing a lower lactate/pyruvate ratio. Additionally, in vitro studies further exhibited that Rd protected isolated mitochondria from calcium-induced damage by attenuating mitochondrial swelling, preserving MMP and decreasing ROS production. Moreover, Rd treatment reduced mitochondrial release of cytochrome c (CytoC) and apoptosis-inducing factor (AIF), thereby minimizing mitochondria-mediated apoptosis following ischemia. In conclusion, these findings demonstrated that Rd exerts neuroprotective effects in transient focal ischemia, which may involve an integrated process of the mitochondrial protection, energy restoration and inhibition of apoptosis.