Effectiveness and safety of Injinoryung-San-Gagambang (Yinchen Wuling powder) decoction on stroke patients with elevated serum liver enzymes: Three case reports.

RATIONALE: Injinoryung-San-Gagambang (IJORS) effectively improves hepatic dysfunction caused by polypharmacy in stroke patients. PATIENT CONCERNS: We present 3 cases of hepatic dysfunction caused by polypharmacy, one of which was a 51-year-old man with cerebellum infarction and pneumonia as a complication of stroke. He took multiple medications because of baseline diseases. After recurrence of pneumonia, his laboratory tests showed abnormal aminotransferase levels. Another patient was an 81-year-old woman with cerebral infarction at the right-middle cerebral artery. She was also taking >5 medications. Her laboratory tests conducted on admission showed abnormally elevated aminotransferase levels. The last patient was 77-year-old man with cerebral infarction at the left-middle cerebral artery. He also had an abdominal aneurysm, a thoracic aortic aneurysm, and a myocardial infarction. After taking multiple medications including healthy functional foods, his laboratory tests showed abnormally elevated aminotransferase levels. DIAGNOSIS: Diagnosis is conducted with the result of laboratory test including blood count, chemistry test. INTERVENTIONS: All 3 patients received the same herbal treatment (IJORS decoction) for 1 to 3 weeks. OUTCOMES: All 3 patients' abnormal serum aminotransferase level were significantly improved by IJORS decoction treatment while keeping other medicines. LESSONS: IJORS can be considered as an effective treatment for hepatic dysfunction induced by numerous medications in stroke patients.

Inhibition of Gelatinases (MMP-2 and MMP-9) by Withania somnifera Phytochemicals Confers Neuroprotection in Stroke: An In Silico Analysis.

A stroke or cerebrovascular accident is a serious, life-threatening medical condition that occurs when the blood supply to part of the brain is severely reduced or cut off, depriving brain tissue of oxygen and nutrients. Studies suggested that level of gelatinases (MMP-2 and MMP-9) usually increases in the brain after stroke. The elevated activity of gelatinases plays the deleterious role in ischemic stroke, hemorrhagic stroke and perinatal hypoxic-ischemic brain injury. Therefore, matrix metalloproteinase (MMP)-2 and MMP-9 inhibition have therapeutic importance in stroke condition. Present in silico study investigates whether Withania somnifera (WS) phytochemicals inhibit the MMP-2 and MMP-9 by binding to the catalytic domain, as similar to their inhibitor or not. For that, we performed molecular docking study to evaluate the gelatinases-inhibitory potential of 36 WS phytochemicals, which compared with gelatinases inhibitors viz. hydroxamic acid, quercetin, doxycycline, minocycline and reverse hydroxamate. The results suggest that 28 out of 36 WS phytochemicals show higher affinity for MMP-2 owing to bind with active site residues of S1'-pocket with lower binding energy and smaller inhibition constant (Ki) than considered inhibitors. As well as, withanolide G and withafastuosin E show higher affinity for MMP-9 than reverse hydroxamate inhibitor. These phytochemicals have neuroprotective potential as an inherently useful oral drug to combat ischemic and hemorrhagic stroke mediated by gelatinases.

Is Chronic Curcumin Supplementation Neuroprotective Against Ischemia for Antioxidant Activity, Neurological Deficit, or Neuronal Apoptosis in an Experimental Stroke Model?

AIM: To investigate the neuroprotective effect of chronic curcumin supplementation on the rat forebrain prior to ischemia and reperfusion. MATERIAL AND METHODS: Forebrain ischemia was induced by bilateral common carotid artery occlusion for 1/2 hour, followed by reperfusion for 72 hours. Older rats were divided into five groups: Group I received 300 mg/kg oral curcumin for 21 days before ischemia and 300 mg/kg intraperitoneal curcumin after ischemia; Group II received 300 mg/kg intraperitoneal curcumin after ischemia; Group III received 300 mg/kg oral curcumin for 21 days before ischemia; Group IV had only ischemia; Group V was the sham-operated group. The forebrain was rapidly dissected for biochemical parameter assessment and histopathological examination. RESULTS: In forebrain tissue, enzyme activities of superoxide dismutase, glutathione peroxidase, and catalase were significantly higher in Group I than Groups II or III (p < 0.05) while xanthine dehydrogenase and malondialdehyde enzyme activities and concentrations of interleukin-6 and TNF-alpha were significantly lower in Group I when compared to Groups II and III (p < 0.05). A significant reduction in neurological score was observed after 24 and 72 hours in the curcumin-treated groups compared with the ischemic group. We also found a marked reduction in apoptotic index after 72 hours in the groups receiving curcumin. Significantly more TUNEL-positive cells were observed in the ischemic group compared to those treated with curcumin. CONCLUSION: We demonstrated the neuroprotective effect of chronic curcumin supplement on biochemical parameters, neurological scores and apoptosis following ischemia and reperfusion injury in rats.

Arginase I release from activated neutrophils induces peripheral immunosuppression in a murine model of stroke.

Transient suppression of peripheral immunity is a major source of complication for patients suffering from ischemic stroke. The release of Arginase I (ArgI) from activated neutrophils has recently been associated with T-cell dysfunction in a number of pathologies. However, this pathway has not been previously explored in ischemic stroke. Using the murine model of transient middle cerebral artery occlusion, we explored effects of stroke on peripheral T-cell function and evaluated the role of neutrophils and ArgI. Stimulation of splenic T cells from post-stroke animals with anti-CD3/CD28 resulted in decreased proliferation and interferon-γ production when compared with sham-surgery controls. Flow cytometric analysis of intrasplenic leukocytes exposed the presence of a transient population of activated neutrophils that correlated quantitatively with elevated ArgI levels in culture media. In vitro activation of purified resting neutrophils from unmanipulated controls confirmed the capacity for murine neutrophils to release ArgI from preformed granules. We observed decreased expression of the L-arg-sensitive CD3ζ on T cells, consistent with decreased functional activity. Critically, L-arg supplementation restored the functional response of post-stroke T cells to mitogenic stimulation. Together, these data outline a novel mechanism of reversible, neutrophil-mediated peripheral immunosuppression related to ArgI release following ischemic stroke.

Heme oxygenase 1-mediated neurogenesis is enhanced by Ginkgo biloba (EGb 761®) after permanent ischemic stroke in mice.

Stroke is the fourth leading cause of death and a major cause of disability in stroke survivors. Studies have underlined the importance of repair mechanisms in the recovery phase of stroke. Neurogenesis in response to brain injury is one of the regeneration processes that, if enhanced, may offer better stroke treatment alternatives. Previously, we have demonstrated antioxidant, neuritogenic, and angiogenic properties of Ginkgo biloba/EGb 761® (EGb 761) in different mouse models of stroke. In the present study, we were interested to study whether EGb 761 could protect mice from permanent middle cerebral artery occlusion (pMCAO) and enhance neurogenesis. EGb 761 pre- and posttreated mice had lower infarct volume and improved motor skills with enhanced proliferation of neuronal stem/progenitor cells (NSPCs) at 24 h and 7 days posttreatment. Netrin-1 and its receptors (DCC and UNC5B) that mediate axonal attraction and repulsion were observed to be overexpressed in NSPCs only, implying that netrin-1 and its receptors might have partly played a role in enhanced neurogenesis. Interestingly, in heme oxygenase 1 knockout mice (HO1(-/-)), neurogenesis was significantly lower than in vehicle-treated mice at day 8. Furthermore, EGb 761 posttreated mice also demonstrated heme oxygenase 1 (HO1)-activated pathway of phosphorylated glycogen synthase kinase 3 α/ß (p-GSK-3 α/ß), collapsin response mediator protein 2 (CRMP-2), semaphorin3A (SEMA3A), and Wnt, suggesting probable signaling pathways involved in proliferation, differentiation, and migration of NSPCs. Together, these results propose that EGb 761 not only has antioxidant, neuritogenic, and angiogenic properties, but can also augment the repair and regeneration mechanisms following stroke.

Transgenic overproduction of omega-3 polyunsaturated fatty acids provides neuroprotection and enhances endogenous neurogenesis after stroke.

Strokes are devastating as there are no current therapies to prevent the long term neurological deficits that they cause. Soon after ischemic stroke, there is proliferation and differentiation of neural stem/progenitor cells as an important mechanism for neuronal restoration. However, endogenous neurogenesis by itself is insufficient for effective brain repair after stroke as most newborn neurons do not survive. One fascinating strategy for stroke treatment would thus be maintaining the survival and/or promoting the differentiation of endogenous neural stem/progenitor cells. Using transgenic (Tg) mice over-expressing the C. elegans fat-1 gene encoding an enzyme that converts endogenous omega-6 to omega-3 polyunsaturated fatty acids (n-3 PUFAs), we showed that fat-1 Tg mice with chronically elevated brain levels of n-3 PUFAs exhibited less brain damage and significantly improved long-term neurological performance compared to wild type littermates. Importantly, post-stroke neurogenesis occurred more robustly in fat-1 Tg mice after focal ischemia. This was manifested by enhanced neural stem cell proliferation/differentiation and increased migration of neuroblasts to the ischemic sites where neuroblasts matured into resident neurons. Moreover, these neurogenic effects were accompanied by significantly increased oligodendrogenesis. Our results suggest that n-3 PUFA supplementation is a potential neurogenic and oligodendrogenic treatment to naturally improve post-stroke brain repair and long-term functional recovery.

Tocotrienol vitamin E protects against preclinical canine ischemic stroke by inducing arteriogenesis.

Vitamin E consists of tocopherols and tocotrienols, in which α-tocotrienol is the most potent neuroprotective form that is also effective in protecting against stroke in rodents. As neuroprotective agents alone are insufficient to protect against stroke, we sought to test the effects of tocotrienol on the cerebrovascular circulation during ischemic stroke using a preclinical model that enables fluoroscopy-guided angiography. Mongrel canines (mean weight=26.3±3.2 kg) were supplemented with tocotrienol-enriched (TE) supplement (200 mg b.i.d, n=11) or vehicle placebo (n=9) for 10 weeks before inducing transient middle cerebral artery (MCA) occlusion. Magnetic resonance imaging was performed 1 hour and 24 hours post reperfusion to assess stroke-induced lesion volume. Tocotrienol-enriched supplementation significantly attenuated ischemic stroke-induced lesion volume (P<0.005). Furthermore, TE prevented loss of white matter fiber tract connectivity after stroke as evident by probabilistic tractography. Post hoc analysis of cerebral angiograms during MCA occlusion revealed that TE-supplemented canines had improved cerebrovascular collateral circulation to the ischemic MCA territory (P<0.05). Tocotrienol-enriched supplementation induced arteriogenic tissue inhibitor of metalloprotease 1 and subsequently attenuated the activity of matrix metalloproteinase-2. Outcomes of the current preclinical trial set the stage for a clinical trial testing the effects of TE in patients who have suffered from transient ischemic attack and are therefore at a high risk for stroke.

Heme oxygenase 1, beneficial role in permanent ischemic stroke and in Gingko biloba (EGb 761) neuroprotection.

Ginkgo biloba extract, EGb 761, a popular and standardized natural extract, contains 24% ginkgo-flavonol glycosides and 6% terpene lactones. EGb 761 is used worldwide to treat many ailments, and although a number of studies have shown its neuroprotective properties, the mechanisms of action have not been elucidated fully. We hypothesize that EGb 761 and some of its bioactive components [Bilobalide (BB), Ginkgolide A (GA), Ginkgolide B (GB), and Terpene Free Material (TFM)] could provide neuroprotection in ischemic conditions through heme oxygenase 1 (HO1). Mice were subjected to permanent distal middle cerebral artery occlusion (pMCAO) and survived for 7 days. HO1 knockout (HO1⁻/⁻) mice showed significantly higher (P<0.05) infarct volume and Neurologic Deficit Scores (NDS) as compared to their wildtype (WT) counterparts. In another cohort, WT mice subjected to pMCAO and treated at 4 h of pMCAO with 100 mg/kg EGb 761, 6 mg/kg BB, GA, GB, or 10 mg/kg TFM showed significantly lower (P<0.05) infarct volumes (BB; 29.0±3.9%, GA; 31.3±4.0%, GB; 32.0±3.8%, TFM; 32.5±3.5%, and EGb 761; 27.4±4.5%) than those in the vehicle-treated mice (46.0±3.7%). Similarly, NDS were lower in BB; 7.1±1.8, GA; 7.4±2.1, GB; 7.9±1.8, TFM; 7.7±1.7, and EGb 761; 6.8±2.0 groups as compared with the vehicle-treated group (13.8±1.5). Interestingly, the protective effect of EGb 761 was essentially lost when HO1 knockout mice were treated with EGb 761. In another cohort, HO1, vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) protein levels in the brain cortices appeared to be higher in EGb 761 and BB but not in GA, GB and TFM treated groups. Together, these results suggest that HO1 plays, at least in part, an important role in the neuroprotective mechanism of EGb 761 and in delayed ischemia. Targeting this pathway could lead to neuroprotective agents against ischemic stroke.

Traditional Chinese medicine, Xue-Fu-Zhu-Yu decoction, potentiates tissue plasminogen activator against thromboembolic stroke in rats.

AIM OF THIS STUDY: The Xue-Fu-Zhu-Yu decoction (XFZYD) is a well-known traditional Chinese medicine for treating cardiovascular diseases. The therapeutic effects of this XFZYD have been well documented especially in treating of atherosclerosis and hyperlipidemia. Since this decoction can induce endothelial progenitor cell angiogenesis, it can provide experimental evidence for the treatment of ischemic diseases. Patients who are admitted to the hospital with acute ischemic stroke are initially considered candidates for the recombinant tissue plasminogen activator (rt-PA). However, rt-PA therapy is still lesser than ideal due to its major side effect of hemorrhaging. Therefore, medical research has been devoted to finding an alternative and/or complementary therapy for ischemic stroke. In the present study, we evaluated the protective effect of the combination of XFZYD with or without rt-PA in a rat model of thromboembolic stroke. MATERIALS AND METHODS: A cerebral thromboembolic stroke animal model and immunoblotting analysis were used to assess the effects of XFZYD and rt-PA. RESULTS: Treatment with rt-PA (8 mg/kg) or XFZYD (1.5 and 3.0 g/kg/day) alone showed slight reductions in the infarct volume compared to solvent-treated rats. However, XFZYD (1.5 and 3.0 g/kg/day) obviously potentiated rt-PA-mediated reduction in the infarct volume in cerebral ischemic regions. In addition, treatment with rt-PA significantly reduced both tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) but not hypoxia-inducible factor (HIF)-1 α or active caspase-3 expressions in ischemic regions, whereas treatment with XFZYD (3.0 g/kg/day) significantly reduced all of these protein expressions in ischemic regions. Moreover, treatment with XFZYD (1.5 and 3.0 g/kg/day) obviously potentiated rt-PA-mediated reductions in TNF-α, iNOS, HIF-1 α, and active caspase-3 expressions. CONCLUSIONS: Results of this study suggest that XFZYD potentiated rt-PA-mediated neuroprotection against thromboembolic stroke in rats. This neuroprotection is probably mediated by the inhibition of HIF-1 α and TNF-α, followed by the inhibition of inflammatory responses (i.e., iNOS) and apoptosis (active caspase-3). These results provide a better understanding of the scientific validation of the therapeutic value of the combination of XFZYD with rt-PA in ischemic stroke.

Electrical stimulation of the cerebral cortex exerts antiapoptotic, angiogenic, and anti-inflammatory effects in ischemic stroke rats through phosphoinositide 3-kinase/Akt signaling pathway.

BACKGROUND AND PURPOSE: Neuroprotective effects of electric stimulation have been recently shown in ischemic stroke, but the underlying mechanisms remain poorly understood. METHODS: Adult Wistar rats weighing 200 to 250 g received occlusion of the right middle cerebral artery for 90 minutes. At 1 hour after reperfusion, electrodes were implanted to rats on the right frontal epidural space. Electric stimulation, at preset current (0 to 200 microA) and frequency (0 to 50 Hz), was performed for 1 week. Stroke animals were subjected to behavioral tests at 3 days and 1 week postmiddle cerebral artery and then immediately euthanized for protein and immunohistochemical assays. After demonstration of behavioral and histological benefits, subsequent experiments pursued the mechanistic hypothesis that electric stimulation exerted antiapoptotic effects through the phosphoinositide 3-kinase-dependent pathway; thus, cortical stimulation was performed in the presence or absence of specific inhibitors of phosphoinositide 3-kinase (LY294002) in stroke rats. RESULTS: Cortical stimulation abrogated the ischemia-associated increase in apoptotic cells in the injured cortex by activating antiapoptotic cascades, which was reversed by the phosphoinositide 3-kinase inhibitor LY294002 as reflected behaviorally and immunohistochemically. Furthermore, brain levels of neurotrophic factors (glial cell line-derived neurotrophic factor, brain-derived neurotrophic factor, vascular endothelial growth factor) were upregulated, which coincided with enhanced angiogenesis and suppressed proliferation of inflammatory cells in the ischemic cortex. CONCLUSIONS: These results suggest that electric stimulation prevents apoptosis through the phosphoinositide 3-kinase pathway. Consequently, the ischemic brain might have been rendered as a nurturing microenvironment characterized by robust angiogenesis and diminished microglial/astrocytic proliferation, resulting in the reduction of infarct volumes and behavioral recovery. Electric stimulation is a novel and potent therapeutic tool for cerebral ischemia.

Age-dependent effects of testosterone in experimental stroke.

Although male sex is a well-recognized risk factor for stroke, the role of androgens in cerebral ischemia remains unclear. Therefore, we evaluated effects of testosterone on infarct size in both young adult and middle-aged rats (Wistar, 3-month versus 14-month old) and mice (C57/BL6, 3-month versus 12-month old) subjected to middle cerebral artery occlusion. In young adult groups, castrates displayed less ischemic damage as compared with intact males and castrates with testosterone replacement (Cortex: 24% in castrates versus 42% in intact versus 40% with testosterone; Striatum: 45% versus 73% versus 70%) at 22 h reperfusion. Surprisingly, supplementing testosterone in middle-aged rats to the physiologic levels ordinarily seen in young males reduced infarction (Cortex: 2% with testosterone versus 31%; Striatum: 38% with testosterone versus 68%). Testosterone effects on infarct size were blocked by the androgen receptor (AR) antagonist flutamide and further confirmed in young versus middle-aged mice. Baseline cerebral aromatase mRNA levels and activity were not different between young and middle-aged rats. Aromatase activity increased in ischemic tissue, but only in young males. Lastly, stroke damage was not different in aging aromatase knockout mice versus wild-type controls. Our findings indicate that testosterone's effects in experimental stroke are age dependent, mediated via AR, but not cerebral aromatase.

AMP-activated protein kinase in the brain.

Since its discovery as an important regulator of fuel utilization in the periphery, AMP-activated protein kinase (AMPK) has become a contender for many important cell-intrinsic and organismal roles regarding energy balance in the central nervous system. The challenge will be to delineate the mechanisms by which neuronal AMPK can respond to cellular energy requirements as well as whole body energy demands. Thus, under physiological conditions in the brain, hypothalamic AMPK responds to changes in energy balance/food intake, whereas under pathological conditions, AMPK responds globally in the brain to energy challenge. Modulation of fatty acid metabolism affects energy balance in a context-specific manner and may provide an insight into other mechanisms for selective activation or inhibition of AMPK activity for therapeutic applications.

Induction of heme oxygenase-1 by traditional Chinese medicine formulation ISF-1 and its ingredients as a cytoprotective mechanism against oxidative stress.

Traditional medicines are clinically used to treat post-stroke disorders in China. In search of alternative medicines for post-stroke rehabilitation, we recently identified the heme oxygenase-1 (HO-1) pathway as a key mechanism underlying the biological activities of the ischemic stroke formulation ISF-1. This study was designed to further investigate ISF-1 for HO-1 induction in cultured human cells and corresponding cytoprotective effects against oxidative injury. A rat stroke model induced by middle cerebral artery occlusion was employed to verify the activity of ISF-1 in vivo. It was found that HO-1 expression was induced by ISF-1 in a dose- and time-dependent manner. Four ingredients from ISF-1 were identified to be responsible for HO-1 induction. The appropriate combinations of these active ingredients or purified compounds resulted in synergistic induction of HO-1 expression. A minimal HO-1-inducing formulation was prepared and showed significant cytoprotection against H2O2-induced oxidative stress. Collectively, the herbal formulation ISF-1 was capable of inducing HO-1 expression, in vitro and in vivo, offering a potential mechanism for post-stroke rehabilitation. This study may shed light on the development of mechanism-defined therapies based on traditional herbal remedies.

Matrix metalloproteinase-3 (MMP3) and MMP9 genes and risk of myocardial infarction, ischemic stroke, and hemorrhagic stroke.

OBJECTIVE: We assessed the association of genetic variation in MMP3 and MMP9 with risk of myocardial infarction and stroke. METHODS: A case-control study was conducted among members of Group Health (GH), a large-integrated health care delivery system. Case subjects with incident non-fatal myocardial infarction (n=854), ischemic stroke (n=367), and hemorrhagic stroke (n=66) were identified and validated. A matched control group was selected from among GH members without myocardial infarction or stroke (n=2696). Haplotype-tagging sets of single-nucleotide polymorphisms (SNPs) in MMP3 and MMP9 were genotyped. RESULTS: MMP3 haplotype 2 was associated with reduced risk of myocardial infarction (adjusted odds ratio (OR) per copy=0.80, 95% confidence interval 0.66, 0.98) and increased risk of hemorrhagic stroke (OR=1.69, 95% confidence interval 1.05, 2.75). Results for MMP3 haplotype 2 and ischemic stroke resembled those for myocardial infarction but did not achieve statistical significance (OR=0.85, 95% confidence interval 0.64, 1.12). No individual SNP identified MMP3 haplotype 2, and none of the individual MMP3 SNPs were associated with myocardial infarction or stroke. MMP9 haplotypes or SNPs were not associated with myocardial infarction or stroke. CONCLUSIONS: MMP3 haplotype may predict both cardiac events and stroke.

Effects of long-term administration of HMG-CoA reductase inhibitor, atorvastatin, on stroke events and local cerebral blood flow in stroke-prone spontaneously hypertensive rats.

The objective of this study was to determine whether the long-term administration of an HMG-CoA reductase inhibitor, atorvastatin, confers protective effects against stroke events in stroke-prone spontaneously hypertensive rats (SHRSPs). Atorvastatin (2 mg/kg, 20 mg/kg) or vehicle was orally administered to 8-week-old SHRSPs for 11 weeks. The survival ratio and stroke incidence were calculated, and plasma lipids and plasma levels of asymmetric dimethylarginine (ADMA), a circulating endogenous competitive inhibitor of NO synthase, were measured after sacrifice. The effect of atorvastatin on local cerebral blood flow (l-CBF) was also determined in 13-week-old SHRSPs after treatment with 20 mg/kg atorvastatin daily for 5 weeks. The survival ratios at 19 weeks of age were 15, 30, and 50% in the vehicle, low-dose (2 mg/kg), and high-dose groups (20 mg/kg), respectively. The survival ratio was significantly higher in the high-dose group than in the vehicle group. The incidence of stroke was significantly lower in the high-dose group than in the vehicle group. The levels of ADMA were 0.81+/-0.18 (mean+/-S.D.), 0.62+/-0.09, and 0.61+/-0.06 micromol/l in the vehicle, low-dose, and high-dose groups, respectively. Atorvastatin administration significantly reduced the ADMA levels without affecting the levels of plasma lipids. The level of l-CBF tended to be higher in the treated group, but not to a significant extent. Thus, atorvastatin was determined to confer a protective effect against hypertension-based stroke. The data suggest that the efficacy of the statin for stroke protection may be partially involved in the improvement of endothelial function via NO production and reduction of ADMA. Statins may confer useful protection against not only atherosclerosis-based stroke, but also hypertension-based stroke.

Dietary lipids impacts on healthy ageing.

Healthy ageing is gaining attention in the lipid nutrition field. As in vivo biomarkers of healthy ageing, we have evaluated the survival, learning/memory performance, and physical potencies in rodents fed a diet supplemented with high-linoleic acid (LNA, omega6) safflower oil or high-alpha-linolenic acid (ALA, omega3) perilla oil for long periods. The results suggested that perilla oil with a low omega6/omega3 ratio is beneficial for healthy ageing. In order to address this issue further, we determined the survival of stroke-prone SHR (SHRSP) rats fed a conventional rodent diet supplemented with 10% fat or oil. Survival was longer with omega3-rich oils compared with omega6-rich oils. However, some kinds of vegetable oils and hydrogenated oils shortened the survival of SHRSP rats to an unusual degree (ca. 40% compared with that of omega6-rich oil) that could not be accounted for by the fatty acid and phytosterol composition of the oils. The observed decrease in platelet counts was associated with pathological changes in the kidney and other organs. Dihydro-vitamin K1 is proposed as a likely candidate as a stroke-stimulating factor in hydrogenated oils. Thus, factors other than fatty acids (omega6/omega3 balance) and phytosterols must be taken into account when fats and oils are evaluated in relation to healthy ageing.

Humanin is a novel neuroprotective agent against stroke.

BACKGROUND AND PURPOSE: Humanin (HN) is a 24-amino acid peptide best known for its ability to protect neurons from damage caused by Alzheimer disease-related proteins. This study examines the neuroprotective effects of HNG (a potent form of HN) on focal cerebral ischemia/reperfusion injury in mice. METHODS: Mice underwent middle cerebral artery occlusion for 75 minutes followed by 24-hour reperfusion. Mice were pretreated with 0.1 microg HNG (intracerebroventricularly) 30 minutes before ischemia; posttreated at 0, 2, 4, and 6 hours after ischemia; or pretreated with 1 microg HNG (intraperitoneally) 1 hour before ischemia. Neurological deficits and cerebral infarct volume were evaluated. Neuronal apoptosis and activated poly(ADP-ribose) polymerase expression were measured by TUNEL and Western blot analysis, respectively. Activated ERKs were examined by Western blot analysis. RESULTS: Pretreatment with 0.1 microg HNG (intracerebroventricularly) 30 minutes before ischemia reduced cerebral infarct volume from 56.2+/-3.0% to 26.1+/-1.4% (P<0.01). HNG posttreatment after 4 hours of reperfusion reduced cerebral infarct volume to 45.6+/-2.6% (P<0.05). Pretreatment with 1 microg HNG (intraperitoneally) 1 hour before ischemia or posttreatment after 2 hours of reperfusion reduced cerebral infarct volume significantly. HNG also significantly improved neurological function and inhibited both neuronal apoptosis as well as poly(ADP-ribose) polymerase activation. A significant decrease of phospho-ERK was observed in mice treated with HNG, whereas phospho-JNK and phospho-p38 levels were not altered. CONCLUSIONS: Our results demonstrate that HNG protects against cerebral ischemia/reperfusion injury in mice. HNG offers neuroprotection in vivo at least in part by inhibiting ERK activation. These findings suggest a potential therapeutic role for HNG in the treatment of stroke.

Homozygous MTHFR C677T gene mutation and recurrent stroke in an infant.

The role of homozygosity for the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene as an independent risk factor for primary and recurrent stroke has been questioned, although recent data appear to be supportive. However, the association of homozygous C677T MTHFR mutation with silent brain infarctions in infancy has not been reported. The authors describe an 11-month-old male who had suffered a silent brain infarction followed by a symptomatic arterial stroke. The evaluation revealed mildly elevated homocysteine levels secondary to homozygous C677T alleles for MTHFR and iron deficiency anemia. An extensive evaluation for other causes of infarction was negative. We suggest that the mother's homozygous MTHFR status played a role in the early onset of stroke and that iron deficiency anemia may have contributed to the recurrence. The patient was treated with anticoagulation therapy, folic acid, and iron supplementation and has not had a recurrent event during 3 years of follow-up. This case provides further evidence that homozygous MTHFR mutation is a predisposing factor for early and recurrent pediatric stroke, including silent infarcts, especially in the presence of other risk factors.

Reduction of tissue plasminogen activator-induced matrix metalloproteinase-9 by simvastatin in astrocytes.

BACKGROUND AND PURPOSE: Hemorrhagic conversion after tissue plasminogen activator (tPA) stroke therapy has been linked with elevations in matrix metalloproteinase-9 (MMP-9) at the neurovascular interface. Here, we test the idea that statins may directly ameliorate tPA-induced MMP-9 dysregulation. METHODS: Recombinant human tPA (5 microg/mL) was added to primary rat cortical astrocytes. Zymography was used to quantify MMP-9 levels in conditioned media. Effects of simvastatin or the Rho kinase inhibitor Y-27632 were assessed by pretreating cells before tPA exposure. RESULTS: Simvastatin (1 to 10 micromol/L) significantly reduced tPA-induced MMP-9 in cortical astrocytes. This effect may be mediated via the Rho kinase pathway because tPA-induced activation of Rho signaling was suppressed by simvastatin, and tPA-induced MMP-9 levels were similarly reduced by the Rho kinase inhibitor Y-27632 (1 to 10 micromol/L). CONCLUSIONS: Statins reduce tPA-induced MMP-9 dysregulation by inhibiting the Rho signaling pathway. Statins may ameliorate tPA-associated MMP imbalances in stroke.

Antioxidant status in acute stroke patients and patients at stroke risk.

BACKGROUND AND PURPOSE: Antioxidant enzymes like copper/zinc superoxide dismutase (SOD), catalase and gluthatione peroxidase (GSHPx) are part of intracellular protection mechanisms to overcome oxidative stress and are known to be activated in vascular diseases and acute stroke. We investigated the differences of antioxidant capacity in acute stroke and stroke risk patients to elucidate whether the differences are a result of chronic low availability in arteriosclerosis and stroke risk or due to changes during acute infarction. METHODS: Antioxidant enzymes were examined in 11 patients within the first hours and days after acute ischemic stroke and compared to risk- and age-matched patients with a history of stroke in the past 12 months (n = 17). Antioxidant profile was determined by measurement of glutathione (GSH), malondialdehyde (MDA), SOD, GSHPx and minerals known to be involved in antioxidant enzyme activation like selenium, iron, copper and zinc. RESULTS: In comparison to stroke risk patients, patients with acute ischemic stroke had significant changes of the GSH system during the first hours and days after the event: GSH was significantly elevated in the first hours (p < 0.01) and GSHPx was elevated 1 day after the acute stroke (p < 0.05). Selenium, a cofactor of GSHPx, was decreased (p < 0.01). GSHPx levels were negatively correlated with National Institutes of Health Stroke Scale (NIHSS) scores on admission (r = -0.84, p < 0.001) and NIHSS scores after 7 days (r = -0.63, p < 0.05). MDA levels showed a trend for elevation in the first 6 h after the acute stroke (p = 0.07). No significant differences of SOD, iron, copper nor zinc levels could be identified. CONCLUSIONS: Differences of antioxidant capacity were found for the GSH system with elevation of GSH and GSHPx after acute stroke, but not for other markers. The findings support the hypothesis that changes of antioxidant capacity are part of acute adaptive mechanisms during acute stroke.