A catalytic antioxidant (AEOL 10150) attenuates expression of inflammatory genes in stroke

Oxidative stress is a major source of injury from cerebral ischemia and reperfusion. We hypothesized that a catalytic antioxidant AEOL 10150 [manganese (III) meso-tetrakis (di-N-ethylimidazole) porphyrin] would attenuate changes in brain gene expression in a mouse model of transient middle cerebral artery occlusion (MCAO). C57BL/6J mice were subjected to either sham surgery or 60 min of right MCAO. AEOL 10150 or phosphate-buffered saline was given intravenously 5 min after onset of reperfusion (n = 6 per group). Six hours later, parenchyma within the MCA distribution was harvested. RNA from the six brains in each group was pooled and mRNA expression determined using an Affymetrix murine MG_U74A v. 2.0 expression microarray. Each experiment was performed three times. The largest changes in expression occurred in stress response and inflammatory genes such as heat shock protein, interleukin-6, and macrophage inflammatory protein-2. Treatment with AEOL 10150 attenuated only the increase in expression of inflammatory genes. This suggests that AEOL 10150 protects brain by attenuating the immune response to ischemia and reperfusion.     

Involvement of gamma protein kinase C in estrogen-induced neuroprotection against focal brain ischemia through G protein-coupled estrogen receptor

The neuroprotective effects of estrogen were studied in the ischemic model mice by 90 min transient unilateral middle cerebral artery occlusion (MCAO) followed by 22.5 h reperfusion. The total infarct size in C57BL/6 female mice after MCAO and reperfusion was significantly smaller than that in male mice. Intraperitoneal injection of estrogen after the start of reperfusion significantly reduced the infarct volume in the male mice. However, no significant gender difference was found in total infarct size in gamma protein kinase C (PKC)-knockout mice, suggesting that the neuroprotective effects of estrogen are due to the activation of a specific subtype of PKC, gammaPKC, a neuron-specific PKC subtype, in the brain. We demonstrated that exogenous estrogen-induced neuroprotection was attenuated in gammaPKC-knockout mice. Immunocytochemical study showed that gammaPKC was translocated to nerve fiber-like structures when observed shortly after MCAO and reperfusion. We also visualized the rapid and reversible translocation of gammaPKC-GFP (green fluorescent protein) by estrogen stimulation in living CHO-K1 cells. These results suggest that the activation of gammaPKC through the G-protein-coupled estrogen receptors on the plasma membrane is involved in the estrogen-induced neuroprotection against focal brain ischemia.     

Low molecular weight catalytic metalloporphyrin antioxidant AEOL 10150 protects lungs from fractionated radiation

The objective of this study was to determine whether administration of a catalytic antioxidant, Mn(III) tetrakis(N,N'-diethylimidazolium-2-yl) porphyrin, AEOL10150, reduces the severity of long-term lung injury induced by fractionated radiation (RT). Fisher 344 rats were randomized into five groups: RT+AEOL10150 (2.5 mg/kg BID), AEOL10150 (2.5 mg/kg BID) alone, RT+ AEOL10150 (5 mg/kg BID), AEOL10150 (5 mg/kg BID) alone and RT alone. Animals received five 8 Gy fractions of RT to the right hemithorax. AEOL10150 was administered 15 min before RT and 8 h later during the period of RT treatment (5 days), followed by subcutaneous injections for 30 days, twice daily. Lung histology at 26 weeks revealed a significant decrease in lung structural damage and collagen deposition in RT+AEOL10150 (5 mg/kg BID) group, in comparison to RT alone. Immunohistochemistry studies revealed a significant reduction in tissue hypoxia (HIF1alpha, CAIX), angiogenic response (VEGF, CD-31), inflammation (ED-1), oxidative stress (8-OHdG, 3-nitrotyrosine) and fibrosis pathway (TGFbeta1, Smad3, p-Smad2/3), in animals receiving RT+ AEOL10150 (5 mg/kg BID). Administration of AEOL10150 at 5 mg/kg BID during and after RT results in a significant protective effect from long-term RT-induced lung injury. Low dose (2.5 mg/kg BID) delivery of AEOL10150 has no beneficial radioprotective effects.     

Low molecular weight catalytic metalloporphyrin antioxidant AEOL 10150 protects lungs from fractionated radiation

The objective of this study was to determine whether administration of a catalytic antioxidant, Mn(III) tetrakis(N,N^′-diethylimidazolium-2-yl) porphyrin, AEOL10150, reduces the severity of long-term lung injury induced by fractionated radiation (RT). Fisher 344 rats were randomized into five groups: RT+AEOL10150 (2.5 mg/kg BID), AEOL10150 (2.5 mg/kg BID) alone, RT+AEOL10150 (5 mg/kg BID), AEOL10150 (5 mg/kg BID) alone and RT alone. Animals received five 8 Gy fractions of RT to the right hemithorax. AEOL10150 was administered 15 min before RT and 8 h later during the period of RT treatment (5 days), followed by subcutaneous injections for 30 days, twice daily. Lung histology at 26 weeks revealed a significant decrease in lung structural damage and collagen deposition in RT+AEOL10150 (5 mg/kg BID) group, in comparison to RT alone. Immunohistochemistry studies revealed a significant reduction in tissue hypoxia (HIF1α, CAIX), angiogenic response (VEGF, CD-31), inflammation (ED-1), oxidative stress (8-OHdG, 3-nitrotyrosine) and fibrosis pathway (TGFβ1, Smad3, p-Smad2/3), in animals receiving RT+AEOL10150 (5 mg/kg BID). Administration of AEOL10150 at 5 mg/kg BID during and after RT results in a significant protective effect from long-term RT-induced lung injury. Low dose (2.5 mg/kg BID) delivery of AEOL10150 has no beneficial radioprotective effects.     

厄贝沙坦对局灶脑缺血作用的实验研究

目的：研究1型血管紧张素Ⅱ受体阻滞剂厄贝沙坦对局灶性脑缺血的神经保护作用及其可能的细胞机制。方法：在激光多谱勒脑血流监测仪对局部脑血流的监测下,应用线栓法建立大鼠大脑中动脉阻塞模型。药物经侧脑室内微泵持续灌注雄性正常血压大鼠,术后行神经功能评分,测定梗死体积,并运用免疫组化染色观察活性Caspase-3及其下游多聚ADP-核糖聚合酶（PARP）p85裂解片断的改变,结合TUNEL,比较各组细胞凋亡情况。结果：厄贝沙坦明显改善大鼠的神经功能评分,第7d的梗死体积较对照组减少了42％,用药后缺血区的TUNEL阳性细胞数．荧光标记的活性Caspase-3以及PARP p85裂解片断表达均明显减少。结论：厄贝沙坦可改善局灶脑缺血的神经功能,抑制细胞凋亡可能是其神经保护机制之一。     

AEOL10150: a novel therapeutic for rescue treatment after toxic gas lung injury

New therapeutics designed as rescue treatments after toxic gas injury such as from chlorine (Cl(2)) are an emerging area of interest. We tested the effects of the metalloporphyrin catalytic antioxidant AEOL10150, a compound that scavenges peroxynitrite, inhibits lipid peroxidation, and has SOD and catalase-like activities, on Cl(2)-induced airway injury. Balb/C mice received 100ppm Cl(2) gas for 5 min. Four groups were studied: Cl(2) only, Cl(2) followed by AEOL10150 1 and 9 h after exposure, AEOL10150 only, and control. Twenty-four hours after Cl(2) gas exposure airway responsiveness to aerosolized methacholine (6.25-50mg/ml) was measured using a small-animal ventilator. Bronchoalveolar lavage (BAL) was performed to assess airway inflammation and protein. Whole lung tissue was assayed for 4-hydroxynonenal. In separate groups, lungs were collected at 72 h after Cl(2) injury to evaluate epithelial cell proliferation. Mice exposed to Cl(2) showed a significantly higher airway resistance compared to control, Cl(2)/AEOL10150, or AEOL10150-only treated animals in response to methacholine challenge. Eosinophils, neutrophils, and macrophages were elevated in BAL of Cl(2)-exposed mice. AEOL10150 attenuated the increases in neutrophils and macrophages. AEOL10150 prevented Cl(2)-induced increase in BAL fluid protein. Chlorine induced an increase in the number of proliferating airway epithelial cells, an effect AEOL10150 attenuated. 4-Hydroxynonenal levels in the lung were increased after Cl(2) and this effect was prevented with AEOL10150. AEOL10150 is an effective rescue treatment for Cl(2)-induced airway hyperresponsiveness, airway inflammation, injury-induced airway epithelial cell regeneration, and oxidative stress.     

Long-term neuroprotection from a potent redox-modulating metalloporphyrin in the rat

Sustained oxidative stress is a known sequel to focal cerebral ischemia. This study examined the effects of treatment with a single dose or sustained infusion of the redox-modulating MnPorphyrin Mn^IIITDE-2-ImP⁵⁺ on outcome from middle cerebral artery occlusion (MCAO) in the rat. Normothermic rats were subjected to 90 min MCAO followed by 90 min reperfusion and then were treated with a single intracerebroventricular dose of Mn^IIITDE-2-ImP⁵⁺. Neurologic and histologic outcomes were assessed at 1 or 8 weeks postischemia. A single dose of Mn^IIITDE-2-ImP⁵⁺ caused a dose-dependent improvement in histologic and neurologic outcome when assessed 1 week postischemia. Mn^IIITDE-2-ImP⁵⁺ afforded preservation of brain aconitase activity at 5.5 h after reperfusion onset, consistent with its known antioxidant properties. Mn^IIITDE-2-ImP⁵⁺ also attenuated postischemic NF-κB activation. Evidence for effects on cerebral infarct size and neurologic function had completely dissipated when rats were allowed to survive for 8 weeks postischemia. In contrast, a 1-week continuous intracerebroventricular Mn^IIITDE-2-ImP⁵⁺ infusion caused persistent and substantive reduction in both cerebral infarct size and neurologic deficit at 8 weeks postischemia. Pharmacologic modulation of postischemic oxidative stress is likely to require sustained intervention for enduring efficacy in improving neurologic and histologic outcome from a transient focal ischemic insult.     

毛蕊异黄酮通过抑制calpain-1的表达发挥抗脑缺血再灌注损伤的研究

目的:探讨毛蕊异黄酮抗脑缺血再灌注损伤的作用是否与抑制calpain-1的表达有关。方法:将SD大鼠随机分为假手术组、模型组以及药物组,采用线栓法建立大鼠大脑中动脉阻断(MCAO)模型,于缺血再灌注前30 min腹腔注射给予20 mg/kg毛蕊异黄酮或等体积的溶剂。再灌注24 h后,行神经功能学评分、脑梗死面积以及神经元凋亡检测;再灌注12 h、24 h时,采用免疫组化和蛋白印迹技术检测大鼠脑皮层calpain-1的表达。结果:与假手术组大鼠比较,MCAO模型组大鼠再灌注24 h后神经功能学评分、梗死面积、神经元凋亡率及calpain-1的表达均明显升高(P0.05),而毛蕊异黄酮能够降低模型组大鼠再灌注24 h后神经功能学评分、梗死面积、神经元凋亡率以及calpain-1的表达(P0.05)。结论:毛蕊异黄酮可能通过抑制calpain-1的表达发挥抗脑缺血再灌注损伤作用。     

Neuroprotective effect of curcumin in middle cerebral artery occlusion induced focal cerebral ischemia in rats

Free radical induced neuronal damage is implicated in cerebral ischemia reperfusion (IR) injury and antioxidants are reported to have neuroprotective activity. Several in vitro and in vivo studies have proved the antioxidant potential of curcumin and its metabolites. Hence, in the present study the neuroprotective potential of curcumin was investigated in middle cerebral artery occlusion (MCAO) induced focal cerebral IR injury. 2 h of MCAO and 22 h of reperfusion resulted in the infarct volume of 210.39 +/- 31.25 mm3. Administration of curcumin 100 and 300 mg/kg, i.p. 30 min. after MCAO produced 37.23 +/- 5.10% and 46.39 +/- 10.23% (p < 0.05) reduction in infarct volume, respectively. Ischemia induced cerebral edema was reduced in a dose dependent manner. Curcumin at 300 mg/kg, i.p. produced 50.96 +/- 6.04% reduction in edema (p < 0.05) volume. Increase in lipid peroxidation after MCAO in ipsilateral and contralateral hemisphere of brain was observed, which was reduced by curcumin (300 mg/kg, i.p.)-treatment. Decrease in superoxide dismutase and glutathione peroxidase activity was observed in ipsilateral hemisphere of MCAO animal. Curcumin-treatment (300 mg/kg, i.p.) prevented IR injury mediated fall in glutathione peroxide activity. Peroxynitrite measured using rhodamine123 fluorescence and anti-nitrotyrosine immunofluorescence indicated increased peroxynitrite formation after IR insult. Curcumin-treatment reduced peroxynitrite formation and hence the extent of tyrosine nitration in the cytosolic proteins. These results suggest the neuroprotective potential of curcumin in cerebral ischemia and is mediated through its antioxidant activity.     

High-soy diet decreases infarct size after permanent middle cerebral artery occlusion in female rats

Estrogen is a powerful neuroprotective agent in rodent models of ischemic stroke. However, in humans, estrogen treatment can increase risk of stroke. Health risks associated with hormone replacement have led many women to consider alternative therapies including high-soy diets or supplements containing soy isoflavones, which act as estrogen receptor ligands to selectively mimic some of estrogen's actions. We hypothesized that a high-soy diet would share the neuroprotective actions of estrogen in focal cerebral ischemia. Female Sprague-Dawley rats were ovariectomized and divided into three groups: isoflavone-free diet + placebo (IF-P), isoflavone-free diet + estradiol (IF-E), or high-soy diet + placebo (S-P). Two weeks after being placed on diets, rats underwent left permanent middle cerebral artery occlusion (MCAO). Reductions in ipsilateral cerebral blood flow were equivalent across groups ( approximately 50%). Twenty-four hours later neurological deficit was determined, and brains were collected for assay of cerebral infarct by TTC staining. In the IF-P rats MCAO produced a 50 +/- 4% cerebral infarct. Estrogen and high-soy diet both significantly reduced the size of the infarcts to 26 +/- 5% in IF-E rats and to 37 +/- 5% in S-P rats. Analysis at five rostro-caudal levels revealed that estrogen treatment was slightly more effective at reducing infarct size than high soy diet. Overall neurological deficit scores at 24 h correlated with infarct size; however, there were no statistically significant differences among the treatment groups. These data show that 2 wk of a high-soy diet is an effective prophylactic strategy for reducing stroke size in a rat model of focal cerebral ischemia.     

Oxidative Stress Contributes to Status Epilepticus Associated Mortality

Status epilepticus is a common manifestation of nerve agent toxicity and represents a serious medical emergency with high rates of mortality and neurologic injury in those that survive. The aim of the current study was to determine if targeting oxidative stress with the catalytic antioxidant, AEOL10150, would reduce pilocarpine-induced mortality and attenuate neuronal death and neuroinflammation. We found that treatment with AEOL10150 in conjunction with scopolamine and diazepam following pilocarpine-induced SE was able to significantly reduce mortality compared to treatment with just scopolamine and diazepam. Mortality was further reduced when AEOL10150 was used in conjunction with atropine and diazepam which is considered the standard of care for nerve agent exposures. Both treatment paradigms offered significant protection against SE-induced oxidative stress. Additionally, treatment with scopolamine, AEOL10150 and diazepam attenuated SE-induced neuronal loss and neuroinflammation. Taken together, the data suggest that pharmacological targeting of oxidative stress can improve survival and attenuate secondary neurological damage following SE induced by the nerve agent surrogate pilocarpine.     

Catalytic antioxidant AEOL 10150 treatment ameliorates sulfur mustard analog 2-chloroethyl ethyl sulfide-associated cutaneous toxic effects

Our previous studies and other published reports on the chemical warfare agent sulfur mustard (SM) and its analog 2-chloroethyl ethyl sulfide (CEES) have indicated a role of oxidative stress in skin injuries caused by these vesicating agents. We examined the effects of the catalytic antioxidant AEOL 10150 in the attenuation of CEES-induced toxicity using our established skin injury models (skin epidermal cells and SKH-1 hairless mice) to validate the role of oxidative stress in the pathophysiology of mustard vesicating agents. Treatment of mouse epidermal JB6 and human HaCaT cells with AEOL 10150 (50 μM) 1 h post-CEES exposure resulted in significant (p < 0.05) reversal of CEES-induced decreases in both cell viability and DNA synthesis. Similarly, AEOL 10150 treatment 1 h after CEES exposure attenuated CEES-induced DNA damage in these cells. Similar AEOL 10150 treatments also caused significant (p < 0.05) reversal of CEES-induced decreases in cell viability in normal human epidermal keratinocytes. Cytoplasmic and mitochondrial reactive oxygen species measurements showed that AEOL 10150 treatment drastically ameliorated the CEES-induced oxidative stress in both JB6 and HaCaT cells. Based on AEOL 10150 pharmacokinetic studies in SKH-1 mouse skin, mice were treated with a topical formulation plus subcutaneous injection (5 mg/kg) of AEOL 10150 1 h after CEES (4 mg/mouse) exposure and every 4 h thereafter for 12 h. This AEOL 10150 treatment regimen resulted in over 50% (p < 0.05) reversal of CEES-induced skin bi-fold and epidermal thickness, myeloperoxidase activity, and DNA oxidation in mouse skin. Results from this study demonstrate the potential therapeutic efficacy of AEOL 10150 against CEES-mediated cutaneous lesions, supporting AEOL 10150 as a medical countermeasure against SM-induced skin injuries.     

Early Treatment with Poly(ADP-Ribose) Polymerase-1 Inhibitor (JPI-289) Reduces Infarct Volume and Improves Long-Term Behavior in an Animal Model of Ischemic Stroke

In patients with stroke and neurodegenerative diseases, overactivation of poly(ADP-ribose) polymerase-1 (PARP-1) causes harmful effects by inducing apoptosis, necrosis, neuroinflammation, and immune dysregulation. The current study investigated the neuroprotective effect of a novel PARP-1 inhibitor, JPI-289, in an animal model of ischemic stroke. A transient middle cerebral artery occlusion (tMCAO, 2 h) model was used to determine the therapeutic effect and the most effective dose and time window of administration of JPI-289. We also investigated the long-term outcomes of treatment with JPI-289 by diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) MRI and by measuring neurological function at 24 h, 7 days, and 28 days after MCAO. The most effective dose and time window of administration of JPI-289 was 10 mg/kg administered 2 h after MCAO with reperfusion. Twenty-four hours after MCAO, infarct volume was reduced by 53% and the number of apoptotic cells was reduced by 56% compared with control. JPI-289 also reduced infarct volume by 16% in the permanent MCAO model. In an MRI-based study, initial infarct volume, as measured using DWI, was similar in the control and JPI-289-treated groups. However, infarct volume and brain swelling were significantly reduced in the group treated with JPI-289 (2 h) at 24 h and 7 days after MCAO. Neurological functions also improved in the group treated with JPI-289 (2 h) until 28 days after MCAO. Inhibition of PARP-1 has neuroprotective effects (reduction of infarct volume and brain swelling) in both tMCAO and pMCAO models of ischemic stroke.     

Inhibition of tobacco smoke-induced lung inflammation by a catalytic antioxidant

Cigarette smokers experience airway inflammation and epithelial damage, the mechanisms of which are unknown. One potential cause may be free radicals either in tobacco smoke or produced during persistent inflammation. Inflammation may also be a driving force to cause airway epithelium to undergo changes leading to squamous cell metaplasia. To test whether tobacco smoke-induced inflammation could be reduced by a catalytic antioxidant, manganese(III)meso-tetrakis(N,N'-diethyl-1,3-imidazolium-2-yl) porphyrin (AEOL 10150) was given by intratracheal instillation to rats exposed to filtered air or tobacco smoke. Exposure to tobacco smoke for 2 d or 8 weeks (6 h/d, 3 d/week) significantly increased the number of cells recovered by bronchoalveolar lavage (BAL). AEOL 10150 significantly decreased BAL cell number in tobacco smoke-treated rats. Significant reductions in neutrophils were noted at 2 d and macrophages at 8 weeks. Lymphocytes were significantly reduced by AEOL 10150 at both time points. Squamous cell metaplasia following 8 weeks of tobacco smoke exposure was 12% of the total airway epithelial area in animals exposed to tobacco smoke without AEOL 10150, compared with 2% in animals exposed to tobacco smoke, but treated with AEOL 10150 (p <.05). We conclude that a synthetic catalytic antioxidant decreased the adverse effects of exposure to tobacco smoke.     

一种改进的小鼠局灶性脑缺血神经症状定量评价方法

本文旨在建立一种客观评价小鼠局灶性脑缺血神经症状的定量方法。在大脑中动脉阻塞诱导局灶性脑缺血后24h,采用悬挂试验分别测定转动的平均角和优势角以及转动次数,并用爬板试验测定小鼠攀爬角度;分析定量测定指标与脑梗死体积、神经元密度的相关性,并与经典的行为学评价方法比较。还以此法观察抗脑缺血药{pranlukast,4-氧-8-[对-(4-苯丁氧基)苯甲酰氨基]-2-(5-四氮基)-4H-1-苯并吡喃半水化合物}(ONO-1078)的作用。结果显示,脑缺血小鼠各项指标均有显著改变,定量评价总分与脑梗死体积、神经元密度减少密切相关,与经典行为学评分之间也密切相关。ONO-1078可显著抑制缺血损伤,并降低定量评价总分。因此,本方法可反映局灶性脑缺血神经症状变化,具有客观、定量、操作简便、无损伤的优点,并能用于评价抗脑缺血药物的作用。     

Valproic acid reduces brain damage induced by transient focal cerebral ischemia in rats: potential roles of histone deacetylase inhibition and heat shock protein induction

Growing evidence from in vitro studies supports that valproic acid (VPA), an anti-convulsant and mood-stabilizing drug, has neuroprotective effects. The present study investigated whether VPA reduces brain damage and improves functional outcome in a transient focal cerebral ischemia model of rats. Subcutaneous injection of VPA (300 mg/kg) immediately after ischemia followed by repeated injections every 12 h, was found to markedly decrease infarct size and reduce ischemia-induced neurological deficit scores measured at 24 and 48 h after ischemic onset. VPA treatment also suppressed ischemia-induced neuronal caspase-3 activation in the cerebral cortex. VPA treatments resulted in a time-dependent increase in acetylated histone H3 levels in the cortex and striatum of both ipsilateral and contralateral brain hemispheres of middle cerebral artery occlusion (MCAO) rats, as well as in these brain areas of normal, non-surgical rats, supporting the in vitro finding that VPA is a histone deacetylase (HDAC) inhibitor. Similarly, heat shock protein 70 (HSP70) levels were time-dependently up-regulated by VPA in the cortex and striatum of both ipsilateral and contralateral sides of MCAO rats and in these brain areas of normal rats. Altogether, our results demonstrate that VPA is neuroprotective in the cerebral ischemia model and suggest that the protection mechanisms may involve HDAC inhibition and HSP induction.     

Baicalin attenuates focal cerebral ischemic reperfusion injury through inhibition of nuclear factor κB p65 activation

Baicalin is a flavonoid compound purified from plant Scutellaria baicalensis Georgi. We aimed to evaluate the neuroprotective effects of baicalin against cerebral ischemic reperfusion injury. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion for 24 h. Baicalin at doses of 50, 100 and 200 mg/kg was intravenously injected after ischemia onset. Twenty-four hours after reperfusion, the neurological deficit was scored and infarct volume was measured. Hematoxylin and eosin (HE) staining was performed to analyze the histopathological changes of cortex and hippocampus neurons. We examined the levels of NF-κB p65 in ischemic cortexes by Western blot analysis and RT-PCR assay. The results showed that the neurological deficit scores were significantly decreased from 2.0 ± 0.7 to 1.2 ± 0.4 and the volume of infarction was reduced by 25% after baicalin injection. Histopathological examination showed that the increase of neurons with pycnotic shape and condensed nuclear in cortex and hippocampus were not observed in baicalin treated animals. Further examination showed that NF-κB p65 in cortex was increased after ischemia reperfusion injury, indicating the molecular mechanism of ischemia reperfusion injury. The level of NF-κB p65 was decreased by 73% after baicalin treatment. These results suggest that baicalin might be useful as a potential neuroprotective agent in stroke therapy. The neuroprotective effects of baicalin may relate to inhibition of NF-κB p65.     

Influence of Pigment Epithelium-Derived Factor on Outcome after Striatal Cerebral Ischemia in the Mouse

We here suggest that pigment epithelium-derived factor (PEDF) does not have an effect on lesion size, behavioral outcome, cell proliferation, or cell death after striatal ischemia in the mouse. PEDF is a neurotrophic factor with neuroprotective, antiangiogenic, and antipermeability effects. It influences self-renewal of neural stem cells and proliferation of microglia. We investigated whether intraventricular infusion of PEDF reduces infarct size and cell death, ameliorates behavioral outcome, and influences cell proliferation in the one-hour middle cerebral artery occlusion (MCAO) mouse model of focal cerebral ischemia. C57Bl6/N mice were implanted with PEDF or artificial cerebrospinal fluid (control) osmotic pumps and subjected to 60-minute MCAO 48 hours after pump implantation. They received daily BrdU injections for 7 days after MCAO in order to investigate cell proliferation. Infarct volumes were determined 24 hours after reperfusion using magnetic resonance imaging. We removed the pumps on day 5 and performed behavioral testing between day 7 and 21. Immunohistochemical staining was performed to determine the effect of PEDF on cell proliferation and cell death. Our model produced an ischemic injury confined solely to striatal damage. We detected no reduction in infarct sizes and cell death in PEDF- vs. CSF-infused MCAO mice. Behavioral outcome and cell proliferation did not differ between the groups. However, we cannot exclude that PEDF might work under different conditions in stroke. Further studies will elucidate the effect of PEDF treatment on cell proliferation and behavioral outcome in moderate to severe ischemic injury in the brain.     

Aminoguanidine Administration Ameliorates Hippocampal Damage After Middle Cerebral Artery Occlusion in Rat

The effects of a selective inducible nitric oxide synthase inhibitor aminoguanidine (AG) on neuronal cells survival in hippocampal CA1 region after middle cerebral artery occlusion (MCAO) were examined. Transient focal cerebral ischemia was induced in rats by 60 or 90 min of MCAO, followed by 7 days of reperfusion. AG treatment (150 mg/kg i.p.) significantly reduced total infarct volumes: by 70% after 90 min MCAO and by 95% after 60 min MCAO, compared with saline-treated ischemic group. The number of degenerating neurons in hippocampal CA1 region was also markedly lower in aminoguanidine-treated ischemic groups compared to ischemic groups without AG-treatment. The number of iNOS-positive cells significantly increased in the hippocampal CA1 region of ischemic animals, whereas it was reduced in AG-treated rats. Our findings demonstrate that aminoguanidine decreases ischemic brain damage and improves neurological recovery after transient focal ischemia induced by MCAO.