4-hydroxy-2-nonenal and Infarction--Middle-Cerebral-Artery

During an acute stroke, reactive oxygen species are overproduced and the endogenous antioxidative defense systems are disrupted. Therefore, antioxidative therapy can be a promising scheme to reduce the severity of stroke. Neumentix is a novel antioxidative supplement produced from a patented mint line and contains a high content of rosmarinic acid (RA). Although Neumentix has proven diverse efficacy and safety in clinical trials, its effect on strokes is unclear.. Mice that were treated with Neumentix or vehicle for 14 days underwent transient middle cerebral artery occlusion (tMCAO) for 60 min. Mice were sacrificed 5 days after tMCAO.. Neumentix preserved body weight after tMCAO, showed a high antioxidative effect in serum, and reduced infarction volume compared to the vehicle. The expression of 4-hydroxy-2-nonenal, Nε-(carboxymethyl) lysine, and 8-hydroxy-2'-deoxyguanosine was reduced in Neumentix-treated mice.. The antioxidative effect of Neumentix was confirmed. This is the first report to demonstrate the antioxidative effect of Neumentix on strokes.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Antioxidants; Brain; Cinnamates; Depsides; Dietary Supplements; Disease Models, Animal; Infarction, Middle Cerebral Artery; Lysine; Male; Mice, Inbred C57BL; Neuroprotective Agents; Oxidative Stress; Reactive Oxygen Species; Rosmarinic Acid

Background and Purpose- Recanalization with tPA (tissue-type plasminogen activator) is the only pharmacological therapy available for patients with ischemic stroke. However, the percentage of patients who may receive this therapy is limited by the risk of hemorrhagic transformation (HT)-the main complication of ischemic stroke. Our aim is to establish whether iron overload affects HT risk, to identify mechanisms that could help to select patients and to prevent this devastating complication. Methods- Mice fed with control or high-iron diet were subjected to thromboembolic stroke, with or without tPA therapy at different times after occlusion. Blood samples were collected for determination of malondialdehyde, matrix metalloproteinases, and fibronectin. Brain samples were collected 24 hours after occlusion to determine brain infarct and edema size, hemorrhage extension, IgG extravasation, and inflammatory and oxidative markers (neutrophil infiltration, 4-hydroxynonenal, and matrix metalloproteinase-9 staining). Results- Despite an increased rate of recanalization, iron-overload mice showed less neuroprotection after tPA administration. Importantly, iron overload exacerbated the risk of HT after early tPA administration, accelerated ischemia-induced serum matrix metalloproteinase-9 increase, and enhanced basal serum lipid peroxidation. High iron increased brain lipid peroxidation at most times and neutrophil infiltration at the latest time studied. Conclusions- Our data showing that iron overload increases the death of the compromised tissues, accelerates the time of tPA-induced reperfusion, and exacerbates the risk of HT may have relevant clinical implications for a safer thrombolysis. Patients with stroke with iron overload might be at high risk of HT after fibrinolysis, and, therefore, clinical studies must be performed to confirm our results.

Topics: Aldehydes; Animals; Blood-Brain Barrier; Disease Models, Animal; Fibrinolytic Agents; Immunoglobulin G; Infarction, Middle Cerebral Artery; Intracranial Hemorrhages; Iron Overload; Iron, Dietary; Lipid Peroxidation; Matrix Metalloproteinase 9; Mice; Neutrophil Infiltration; Oxidative Stress; Stroke; Thromboembolism; Tissue Plasminogen Activator

Oxidative stress and inflammation are important aggravating factors in acute ischemic stroke.. In the present study, the neuroprotective effects of a novel antioxidant mixture Twendee X containing multiple antioxidative ingredients, such as coenzyme Q10, ascorbic acid, and cystine, were evaluated. After the pretreatment of a vehicle or Twendee X (20 mg/kg/d) for 14 days, mice were subjected to transient middle cerebral artery occlusion for 60 minutes and further treated with vehicle or Twendee X for 1 or 5 days.. Twendee X administration reduced the infarct size, and reduced oxidative stress markers such as 8-hydroxy-2'-deoxyguanosine, 4-hydroxy-2-nonenal, and N. In the present study, the neuroprotective effects of Twendee X were shown on transient middle cerebral artery occlusion mice via antioxidative and anti-inflammatory pathways, providing a potential of Twendee X as one preventive and therapeutic treatment.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Brain; Deoxyguanosine; Disease Models, Animal; Glycation End Products, Advanced; Infarction, Middle Cerebral Artery; Inflammation Mediators; Lysine; Male; Mice, Inbred C57BL; Neuroprotective Agents; Oxidative Stress; Time Factors

This study aims to determine if erythromycin provides neuroprotective effects against ischemic injury following permanent focal cerebral ischemia.. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO). Each animal received a single subcutaneous injection of erythromycin lactobionate (EM, 50 mg/kg) or vehicle immediately after ischemia. The infarct volume, edema index and neurological performance were evaluated at 24 and 72 h after MCAO. The cerebral blood flow (CBF) was measured with an MRI system at 30 min after MCAO. TUNEL staining and immunohistochemical analyses for oxidative stress (4-HNE, 8-OHdG) and inflammation (Iba-1, TNF-α) in the cortex were conducted at 24 and 72 h after MCAO.. The CBF did not differ between the EM-treated and vehicle-treated groups. The EM treatment significantly reduced the infarct volume (p < 0.01) at 24 and 72 h after MCAO and significantly reduced the edema index (p < 0.01) at 24 h. The EM treatment significantly improved the neurological deficit scores (p < 0.05) at 24 and 72 h. EM also significantly suppressed the accumulation of 4-HNE (p < 0.01) and 8-OHdG (p < 0.01) and markedly reduced Iba-1 (p < 0.01) and TNF-α expression (p < 0.05) at both time points. The EM treatment significantly reduced TUNEL-positive cells (p < 0.01) at both time points.. These findings suggest that EM can protect against the neuronal damage caused by cerebral ischemia by alleviating inflammation and reducing oxidant stress.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Blood Pressure; Body Temperature; Brain Edema; Brain Infarction; Brain Injuries; Calcium-Binding Proteins; Cerebrovascular Circulation; Deoxyguanosine; Disease Models, Animal; Erythromycin; In Situ Nick-End Labeling; Infarction, Middle Cerebral Artery; Magnetic Resonance Imaging; Microfilament Proteins; Neuroprotective Agents; Rats; Statistics, Nonparametric; Time Factors; Tumor Necrosis Factor-alpha

Despite successful revascularization, reperfusion after prolonged ischemia causes ischemia reperfusion (I/R) injury. Recruitment and activation of neutrophils is thought to be a key event causing I/R injury. We examined whether post-ischemic intra-arterial infusion of liposome-encapsulated hemoglobin (LEH), an artificial oxygen carrier without neutrophils, could reduce I/R injury in a rat transient middle cerebral artery occlusion (MCAO) model. Male Sprague-Dawley rats were subjected to 2-h MCAO and then were divided into three groups: (1) LEH group (n=7) infused with LEH (Hb concentration of 6g/dl, 10ml/kg/h) through the recanalized internal carotid artery for 2h, (2) vehicle group (n=8) infused with saline (10ml/kg/h) in the same manner as the LEH group, and (3) control group (n=9) subjected to recanalization only. After 24-h reperfusion, all rats were tested for neurological score and then sacrificed to examine infarct and edema volumes, myeloperoxidase (MPO) expression, matrix metalloproteinase-9 (MMP-9) expression and activity, and reactive oxygen species (ROS) production. Compared with the control group and the vehicle group, the LEH group showed a significantly better neurological score and significantly smaller infarct and edema volumes. MPO expression, MMP-9 expression and activity, and ROS production in the LEH group were also significantly lower than those in the control and vehicle groups. The results in the present study suggest that post-ischemic intra-arterial infusion of LEH can reduce I/R injury through reducing the effect of MMP-9, most likely produced by neutrophils. This therapeutic strategy may be a promising candidate to prevent I/R injury after thrombolysis and/or thromboectomy.

Topics: Aldehydes; Animals; Brain; Brain Ischemia; Carotid Artery, Internal; Edema; Hemoglobins; Humans; Infarction, Middle Cerebral Artery; Infusions, Intra-Arterial; Liposomes; Male; Matrix Metalloproteinase 9; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Severity of Illness Index

Telmisartan is an angiotensin receptor blocker with high lipid solubility, also called metabosartan, which exerts a special protective effect on both acute brain damage and chronic neurodegeneration. We examined the effects of telmisartan on oxidative stress by advanced glycation end product (AGE) and 4-hydroxynonenal (4-HNE) assays and the accumulation of phosphorylated α-synuclein (pSyn) in the brain of stroke-resistant spontaneously hypertensive rats (SHR-SR). At the age of 12 weeks, SHR-SR received transient middle cerebral artery occlusion (tMCAO) for 90 minutes and were divided into the following 3 groups: the vehicle group, the low-dose telmisartan group (.3 mg/kg/day), and the high-dose telmisartan group (3 mg/kg/day, postoperatively). Immunohistologic analysis was performed when rats were 6, 12, and 18 months old. AGE, 4-HNE, and pSyn-positive cells (per square millimeter) increased with age in the cerebral cortex and hippocampus of the vehicle group, in the low-dose telmisartan group, these parameters decreased without lowering blood pressure (BP), and in the high-dose telmisartan group, these parameters increased with lowering BP. The present study suggests that a persistent hypertension after tMCAO caused a progressive oxidative stress with the abnormal accumulation of pSyn, and that telmisartan reduced oxidative stress and the accumulation of pSyn without lowering BP (low dose) or improved these conditions with a reduction in BP (high dose) via its pleiotropic effects through a potential peroxisome proliferator-activated receptor gamma stimulation in the brain of SHR-SR.

Topics: Aldehydes; Angiotensin II Type 1 Receptor Blockers; Animals; Benzimidazoles; Benzoates; Blood Pressure; Brain; Glycation End Products, Advanced; Hypertension; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Oxidative Stress; Phosphorylation; Rats; Rats, Inbred SHR; Rats, Wistar; Synucleins; Telmisartan

Among several anti-platelet drugs to prevent recurrent stroke, cilostazol has shown various effects besides its anti-platelet activity. We examined whether 7 days of oral administration of cilostazol protects against subsequent cerebral ischemia, and whether or not the effect of combination therapy with aspirin is more protective.. We used Sprague-Dawley (SD) rats and assigned them to four groups: vehicle, aspirin, cilostazol, and aspirin plus cilostazol combination therapy. After oral administration of anti-platelets for 7 days, we performed transient middle cerebral artery occlusion (MCAO) for 90 minutes, and examined infarct volume, neurological symptoms, and regional cerebral blood flow (rCBF). Immunostaining of Bax, Bcl-2, TUNEL, 4-HNE, 8-OHdG, and COX-2 was performed 24 hours after ischemia.. The cilostazol group and the combination therapy group showed significant decreases of infarct volume and significant improvements of rCBF during ischemia, compared with the vehicle or aspirin group. Significant decreases of Bax, TUNEL, 8-OHdG, and 4-HNE expression in the combination therapy group, compared with those in the vehicle or aspirin group, were shown in the boundary zone. COX-2 expression was unexpectedly increased in the combination therapy group.. Aspirin co-administration did not inhibit this effect. The addition of the oral administration of cilostazol either alone or with aspirin administration may be beneficial for subsequent cerebral ischemic damage in terms of reducing infarct volume, improving rCBF during ischemia, inhibiting the apoptotic pathway, and reducing oxidative stress.

Topics: Aldehydes; Animals; Aspirin; bcl-2-Associated X Protein; Brain; Cilostazol; Cyclooxygenase 2; Drug Therapy, Combination; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Tetrazoles

We evaluated the neuroprotective effects of an anti-oxidative nutrient rich enteral diet (AO diet) that contained rich polyphenols (catechins and proanthocyanidins) and many other anti-oxidative ingredients. Wistar rats were treated with either vehicle, normal AO diet (containing 100kcal/100mL, catechin 38.75mg/100mL and proanthocyanidin 19mg/100mL, 1mL/day), or high AO diet (containing 10 times the polyphenols of the normal AO diet) for 14 days, and were subjected to 90min of transient middle cerebral artery occlusion. The AO diet improved motor function, reduced cerebral infarction volume, and decreased both peroxidative markers such as 4-hydroxynonenal, advanced glycation end products, 8-hydroxy-2-deoxyguanosine and inflammatory markers such as monocyte chemotactic protein-1, ionized calcium-binding adapter molecule-1, and tumor necrosis factor-α. Our study has shown that an AO diet has neuroprotective effects through both anti-oxidative and anti-inflammatory mechanisms, indicating that nutritional control with polyphenols could be useful for patients with acute ischemic stroke.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Administration, Oral; Aldehydes; Animals; Antioxidants; Biomarkers; Brain Chemistry; Brain Damage, Chronic; Brain Ischemia; Cerebral Infarction; Deoxyguanosine; Diet; Glycation End Products, Advanced; Infarction, Middle Cerebral Artery; Inflammation; Male; Oxidative Stress; Proanthocyanidins; Rats; Rats, Wistar

Radix Astragali has been commonly used as traditional herbal medicine in China for reinforcing vital energy, strengthening superficial resistance and promoting the discharge of pus and the growth of new tissue.. The present study was to investigate the neuroprotective effect of calycosin isolated from the roots of Radix Astragali on cerebral ischemic/reperfusion injury.. After 24h of reperfusion following ischemia for 2h induced by middle cerebral artery occlusion (MCAO), Sprague-Dawley rats were intragastrically administered different doses of calycosin (7.5, 15, 30 mg/kg, respectively). Neurological deficit, infarct volume, histopathology changes and some oxidative stress markers were evaluated after 24h of reperfusion.. Treatment with calycosin significantly ameliorated neurologic deficit and infarct volume after cerebral ischemia reperfusion. Calycosin also reduced the content of malondialdehyde (MDA), protein carbonyl and reactive oxygen species (ROS), and up-regulated the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px) in a dose-dependent manner. Moreover, calycosin can also inhibit the expression of 4-Hydroxy-2-nonenal (4-HNE).. These results suggest that calycosin has a neuroprotective effect against cerebral ischemia/reperfusion injury. The mechanism might be attributed to its antioxidant effects.

Topics: Aldehydes; Animals; Behavior, Animal; Brain; Catalase; Diagnostic Techniques, Neurological; Disease Models, Animal; Glutathione Peroxidase; Infarction, Middle Cerebral Artery; Isoflavones; Male; Malondialdehyde; Mitochondria; Movement; Neuroprotective Agents; Phytotherapy; Protein Carbonylation; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase

Despite extensive research to develop an effective neuroprotective strategy for the treatment of ischemic stroke, therapeutic options remain limited. Although caspase-dependent death is thought to play a prominent role in neuronal injury, direct evidence of active initiator caspases in stroke and the functional relevance of this activity have not previously been shown. Using an unbiased caspase-trapping technique in vivo, we isolated active caspase-9 from ischemic rat brain within 1 h of reperfusion. Pathogenic relevance of active caspase-9 was shown by intranasal delivery of a novel cell membrane-penetrating highly specific inhibitor for active caspase-9 at 4 h postreperfusion (hpr). Caspase-9 inhibition provided neurofunctional protection and established caspase-6 as its downstream target. The temporal and spatial pattern of expression demonstrates that neuronal caspase-9 activity induces caspase-6 activation, mediating axonal loss by 12 hpr followed by neuronal death within 24 hpr. Collectively, these results support selective inhibition of these specific caspases as an effective therapeutic strategy for stroke.

Topics: Administration, Intranasal; Aldehydes; Animals; Brain Infarction; Caspase 6; Caspase 9; Caspase Inhibitors; Cysteine Proteinase Inhibitors; Disease Models, Animal; Enzyme Inhibitors; Hippocampus; Humans; In Vitro Techniques; Infarction, Middle Cerebral Artery; Inhibitor of Apoptosis Proteins; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nerve Tissue Proteins; Nervous System Diseases; Neurons; PTEN Phosphohydrolase; Rats; Rats, Wistar; Time Factors

The immunosuppressant FK506 (tacrolimus) is neuroprotective in experimental models of cerebral ischemia. However, the precise mechanisms underlying this neuroprotection remain unknown. In the present study, we hypothesized that FK506 treatment could protect rat brain from oxidative injuries through antioxidative and anti-inflammatory pathways after ischemia-reperfusion injury.. Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 120 minutes, followed by reperfusion. Animals received a single injection of FK506 (0·3 mg/kg) or vehicle intravenously at 30 minutes after ischemic induction. Infarct volume and neurological performance were evaluated at 24 hours after reperfusion. Immunohistochemical analysis for 4-hydroxy-2-nonenal (4-HNE), 8-hydroxy-deoxyguanosine (8-OHdG), ionized calcium-binding adapter molecule 1 (Iba-1), and tumor necrosis factor-alpha (TNF-alpha) were conducted at 24 hours after reperfusion.. FK506 significantly reduced infarct volume (61·7%; P=0·01) and improved neurological deficit scores (P<0·05) 24 hours after reperfusion compared to vehicle. In FK506-treated rats, accumulation of 4-HNE (P<0·01) and 8-OHdG (P<0·01) was significantly suppressed in the cerebral cortex 24 hours after reperfusion. In addition, FK506 markedly reduced microglial activation (P<0·01) and TNF-alpha expression (P<0·01).. These results demonstrate that FK506 may have antioxidant as well as anti-inflammatory effects and reduces ischemic damage following cerebral infarction.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Antioxidants; Brain; Calcium-Binding Proteins; Cerebral Infarction; Cerebrovascular Circulation; Deoxyguanosine; Disease Models, Animal; Humans; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Magnetic Resonance Imaging; Male; Microfilament Proteins; Neuroprotective Agents; Oxidative Stress; Rats; Rats, Sprague-Dawley; Tacrolimus; Tumor Necrosis Factor-alpha

Hyperglycemia is one of the major factors for hemorrhagic transformation after ischemic stroke. In this study, we tested the effect of hydrogen gas on hemorrhagic transformation in a rat focal cerebral ischemia model. Sprague-Dawley rats (n=72) were divided into the following groups: sham; sham treated with hydrogen gas (H(2)); Middle Cerebral Artery Occlusion (MCAO); and MCAO treated with H(2) (MCAO+H(2)). All rats received an injection of 50% dextrose (6 ml/kg i.p.) and underwent MCAO 15 min later. Following a 90 min ischemic period, hydrogen was inhaled for 2 h during reperfusion. We measured the level of blood glucose at 0 h, 0.5 h, 4 h, and 6 h after dextrose injection. Infarct and hemorrhagic volumes, neurologic score, oxidative stress (evaluated by measuring the level of 8 Hydroxyguanosine (8OHG), 4-Hydroxy-2-Nonenal (HNE) and nitrotyrosine), and matrix metalloproteinase (MMP)-2/MMP-9 activity were measured at 24 h after ischemia. We found that hydrogen inhalation for 2 h reduced infarct and hemorrhagic volumes and improved neurological functions. This effect of hydrogen was accompanied by a reduction of the expression of 8OHG, HNE, and nitrotyrosine and the activity of MMP-9. Furthermore, a reduction of the blood glucose level from 500+/-32.51 to 366+/-68.22 mg/dl at 4 h after dextrose injection was observed in hydrogen treated animals. However, the treatment had no significant effect on the expression of ZO-1, occludin, collagen IV or aquaporin4 (AQP4). In conclusion, hydrogen gas reduced brain infarction, hemorrhagic transformation, and improved neurological function in rats. The potential mechanisms of decreased oxidative stress and glucose levels after hydrogen treatment warrant further investigation.

Topics: Administration, Inhalation; Aldehydes; Animals; Antioxidants; Aquaporin 4; Brain Damage, Chronic; Cerebral Hemorrhage; Disease Progression; Drug Evaluation, Preclinical; Extracellular Matrix Proteins; Glucose; Hydrogen; Hyperglycemia; Infarction, Middle Cerebral Artery; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neuroprotective Agents; Random Allocation; Rats; Rats, Sprague-Dawley; Tyrosine

Biliverdin (BV), one of the byproducts of heme catalysis through heme oxygenase (HO) system, is a scavenger of reactive oxygen species (ROS). We hypothesized that BV treatment could protect rat brain cells from oxidative injuries via its anti-oxidant efficacies. Cerebral infarction was induced by transient middle cerebral artery occlusion (tMCAO) for 90 min, followed by reperfusion. BV or vehicle was administered intraperitoneally immediately after reperfusion. The size of the cerebral infarction 2 days after tMCAO was evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) stain. Superoxide generation 4 h after tMCAO was determined by detection of oxidized hydroethidine. In addition, the oxidative impairment of neurons were immunohistochemically assessed by stain for lipid peroxidation with 4-hydroxy-2-nonenal (4-HNE) and damaged DNA with 8-hydroxy-2'-deoxyguanosine (8-OHdG). BV treatment significantly reduced infarct volume of the cerebral cortices associated with less superoxide production and decreased oxidative injuries of brain cells. The present study demonstrated that treatment with BV ameliorated the oxidative injuries on neurons and decreased brain infarct size in rat tMCAO model.

Topics: Aldehydes; Animals; Antioxidants; Biliverdine; Cerebral Infarction; Disease Models, Animal; DNA Damage; Infarction, Middle Cerebral Artery; Injections, Intraperitoneal; Male; Neurons; Neuroprotective Agents; Oxidative Stress; Phenanthridines; Rats; Rats, Wistar; Superoxides; Tetrazolium Salts; Treatment Outcome

Our previous studies have shown that ferulic acid (4-hydroxy-3-methoxycinnamic acid, FA) inhibits intercellular adhesion molecule-1 (ICAM-1) expression in the ischemic striatum after 2 h of reperfusion in a transient middle cerebral artery occlusion model in rats. The purpose of this study is to further investigate the neuroprotective effects of FA during reperfusion after cerebral ischemia. Rats were subjected to 90 min of ischemia; they were then sacrificed after 2, 10, 24 and 36 h of reperfusion. ICAM-1 and macrophage-1 antigen (Mac-1) mRNA were detected using semi-quantitative RT-PCR at 2 h of reperfusion. Mac-1, 4-hydroxy-2-nonenal (4-HNE), 8-hydroxy-2'-deoxyguanosine (8-OHdG), active caspase 3, neuronal nuclei (NeuN) and TUNEL positive cells were measured at 2, 10, 24 and 36 h of reperfusion. FA (100 mg/kg, i.v.) administered immediately after MCAo inhibited ICAM-1 and Mac-1 mRNA expression in the striatum at 2 h of reperfusion, and reduced the number of Mac-1, 4-HNE and 8-OHdG positive cells in the ischemic rim and core at 10, 24 and 36 h of reperfusion. FA decreased TUNEL positive cells in the penumbra at 10 h, and in the ischemic boundary and core at 24 and 36 h of reperfusion. FA curtailed active caspase 3 expression in the penumbra at 10 h and restored NeuN-labeled neurons in the penumbra and ischemic core at 36 h of reperfusion. FA decreased the level of ICAM-1 mRNA and the number of microglia/macrophages, and subsequently down-regulated inflammation-induced oxidative stress and oxidative stress-related apoptosis, suggesting that FA provides neuroprotection against oxidative stress-related apoptosis by inhibiting ICAM-1 mRNA expression after cerebral ischemia/reperfusion injury in rats.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Apoptosis; Brain Ischemia; Caspase 3; Coumaric Acids; Deoxyguanosine; Disease Models, Animal; DNA-Binding Proteins; Encephalitis; Free Radical Scavengers; Gene Expression; In Situ Nick-End Labeling; Infarction, Middle Cerebral Artery; Intercellular Adhesion Molecule-1; Macrophage-1 Antigen; Male; Nerve Tissue Proteins; Neuroprotective Agents; Nuclear Proteins; Oxidative Stress; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger

This study aimed to clarify the effect of statins on spontaneous stroke and to examine the antioxidative effect in artificial transient middle cerebral artery occlusion (tMCAO).. Stroke-prone spontaneous hypertensive rats (SHR-SP) were treated with pitavastatin, atorvastatin, simvastatin, or vehicle for 4 weeks. Physiological parameters, serum lipids, and infarct volumes were examined. The markers for oxidative stresses on lipids and DNA were immunohistochemically detected in vehicle-treated or simvastatin-treated SHR-SP with tMCAO.. Atorvastatin and simvastatin decreased infarct volumes, with simvastatin most effective. Simvastatin significantly reduced immunoreactivities for oxidative stress markers for lipids and DNA in neurons after tMCAO.. The results suggest that the antioxidative properties of statins may be implicated in their beneficial effects against neuronal damage in cerebral ischemia.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Atorvastatin; Blood Pressure; Body Weight; Deoxyguanosine; Disease Models, Animal; Heptanoic Acids; Hydroxymethylglutaryl CoA Reductases; Infarction, Middle Cerebral Artery; Lipids; Lysine; Oxidative Stress; Pyrroles; Quinolines; Rats; Rats, Inbred SHR; Simvastatin; Survival Analysis

Numerous studies demonstrate oestrogen's neuroprotective effect in stroke models, although the mechanisms are unclear. Since oestrogen is an antioxidant, we tested the hypothesis that oestrogen reduces stroke-induced damage by reducing free radical damage, particularly lipid peroxidation.. Sprague-Dawley rats were ovariectomised and a 17beta-oestradiol (0.25 mg, 21 day release) or placebo pellet implanted subcutaneously. Two weeks later, permanent middle cerebral artery occlusion (MCAO) was induced by intraluminal filament. At 2 and 24 h post-MCAO, neurological deficits were assessed. At the 24 h end point, plasma oestradiol was measured and brain sections stained with haematoxylin and eosin or lipid peroxidation marker, 4-hydroxynonenol (4-HNE) immunohistochemistry carried out to measure infarct volume and volume of tissue displaying oxidative damage, respectively.. Plasma 17beta-oestradiol in oestradiol and placebo groups was 72.6+/-38.0 and 9.3+/-7.4 pg/ml (mean+/-SD), respectively. Infarct volume was significantly increased (118%) with oestradiol treatment (oestradiol=124+/-84.5, placebo=57+/-46.4 mm3, mean+/-SD, P<0.05). The relationship between 4-HNE and infarct volume was significantly influenced by 17beta-oestradiol. Neurological deficits were similar between groups (oestradiol median=13, placebo=14, max score=33).. Two week pre-treatment with a high physiological dose of 17beta-oestradiol increased infarct volume after permanent MCAO. Although contrary to our original hypothesis, this result demonstrates that oestrogen does have the capacity to promote detrimental actions in the stroke-injured brain. Given the wide use of oestrogen (contraception, osteoporosis and menopause), more research to clarify the influence of oestrogen on brain injury is urgently required.

Topics: Aldehydes; Animals; Antioxidants; Brain Ischemia; Cerebral Cortex; Cerebral Infarction; Disease Models, Animal; Disease Progression; Drug Implants; Estradiol; Female; Infarction, Middle Cerebral Artery; Lipid Peroxidation; Nerve Degeneration; Neurologic Examination; Ovariectomy; Oxidative Stress; Rats; Rats, Sprague-Dawley; Up-Regulation

Statins possess neuroprotective effect against ischemic damage, but how they protect neurons is not exactly made clear. We speculated that anti-oxidative property of statins is implicated, and investigated statins' influences on the oxidative neuronal damage in the brain after ischemia. After 14 days of atorvastatin, pitavastatin, simvastatin, or vehicle administration, 90 min of middle cerebral artery occlusion was imposed on Wistar rats. The production of 4-hydroxynonenal (HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), both of which are oxidative stress markers, as well as infarction formation were investigated at 1 day after the reperfusion. In the vehicle group, massive infarction was confirmed and HNE and 8-OHdG are robustly produced. In the statins-treated group, the infarction was smaller and the HNE and 8-OHdG production was less prominent than the vehicle group. Among the statins investigated, simvastatin was most effective for reducing oxidative stress and infarction volume, which may be brought by its highly lipophilic property. Reduction of oxidative stress by statins may be one main reason in ameliorating ischemic brain damage in rats.

Topics: Aldehydes; Animals; Biomarkers; Brain; Brain Chemistry; Brain Ischemia; Cholesterol; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Immunohistochemistry; Infarction, Middle Cerebral Artery; Lipid Peroxidation; Male; Neurons; Oxidative Stress; Rats; Rats, Wistar; Triglycerides

White matter of the neonatal brain is highly sensitive to hypoxic-ischemic insult. The susceptibility of premature oligodendrocytes (OLs) to free radicals (FRs) produced during hypoxia-ischemia (HI) has been proposed as one of the mechanisms involved. To test this hypothesis, and to further investigate if the FR scavenger alpha-phenyl-N-tert-butyl-nitrone (PBN) attenuates hypoxic-ischemic white matter damage (WMD), postnatal day 4 (P4) SD rats were subjected to bilateral common carotid artery ligation (BCAL), followed by 8% oxygen exposure for 20 min. Pathological changes were evaluated on P6 and P9, 2 and 5 days after the HI insult. HI caused severe WMD including rarefaction, necrosis and cavity formation in the corpus callosum, external and internal capsule areas. OL injury was evidenced by degeneration of O4 positive OLs on P6. Disrupted myelination was verified by decreased immunostaining of myelin basic protein (MBP) on P9. Axonal injury was demonstrated by increased amyloid precursor protein (APP) immunostaining on both P6 and P9. Two lipid peroxidation end products, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), showed a one-fold elevation within 1-24 h following HI. 4-HNE immunostaining was found to specifically localize in the white matter area. Furthermore, pyknotic O4+ OLs were double-labeled with 4-HNE. These findings suggest that FRs are involved in the pathogenesis of neonatal WMD. PBN (100 mg/kg, i.p.) treatment alleviated the pathological changes of WMD following HI. It improved the survival of O4 positive OLs, attenuated hypomyelination and reduced axonal damage. PBN treatment also decreased the brain concentration of MDA/4-HNE and positive 4-HNE staining in the white matter area. These findings indicate that in the current WMD model, PBN protects both OLs and axons, the two main components in the white matter, from neonatal HI insult. FR scavenging appears to be the primary mechanism underlying its neuroprotective effect.

Topics: Age Factors; Aldehydes; Amyloid beta-Peptides; Analysis of Variance; Animals; Animals, Newborn; Antigens, Differentiation; Brain; Cell Count; Cell Survival; Cyclic N-Oxides; Free Radical Scavengers; Hypoxia-Ischemia, Brain; Immunohistochemistry; Infarction, Middle Cerebral Artery; Malondialdehyde; Myelin Basic Protein; Nitrogen Oxides; Oligodendroglia; Rats; Staining and Labeling; Time Factors

Lipid peroxidation and the cytotoxic by-product 4-hydroxynonenal (4-HNE) have been implicated in neuronal perikaryal damage. This study sought to determine whether 4-HNE was involved in white matter damage in vivo and in vitro. Immunohistochemical studies detected an increase in cellular and axonal 4-HNE within the ischemic region in the rat after a 24-hour period of permanent middle cerebral artery occlusion. Exogenous 4-HNE (3.2 nmol) was stereotaxically injected into the subcortical white matter of rats that were killed 24 hours later. Damaged axons detected by accumulation of beta-amyloid precursor protein (beta-APP) were observed transversing medially and laterally away from the injection site after intracerebral injection of 4-HNE. In contrast, in the vehicle-treated animals, axonal damage was restricted to an area immediately surrounding the injection site. Exogenous 4-HNE produced oligodendrocyte cell death in culture in a time-dependent and a concentration-dependent manner. After 4 hours, the highest concentration of 4-HNE (50 micromol/L) produced 100% oligodendrocyte cell death. Data indicate that lipid peroxidation and production of 4-HNE occurs in white matter after cerebral ischemia and the lipid peroxidation by-product 4-HNE is toxic to axons and oligodendrocytes.

Topics: Aldehydes; Amyloid beta-Protein Precursor; Animals; Axons; Brain Ischemia; Free Radicals; In Vitro Techniques; Infarction, Middle Cerebral Artery; Lipid Peroxidation; Male; Neurotoxins; Oligodendroglia; Rats; Rats, Sprague-Dawley