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1.
BMJ Open ; 13(8): e075612, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37620264

ABSTRACT

OBJECTIVES: To examine whether the Areal Deprivation Index (ADI), an indicator of the socioeconomic status of the community the patient resides in, is associated with delayed arrival at the hospital and poor outcomes in patients with acute ischaemic stroke from a prefecture-wide stroke database in Japan. DESIGN: Retrospective study. SETTING: Twenty-nine acute stroke hospitals in Kochi prefecture, Japan. PARTICIPANTS: Nine thousand and six hundred fifty-one patients with acute ischaemic stroke who were urgently hospitalised, identified using the Kochi Acute Stroke Survey of Onset registry. Capital and non-capital areas were analysed separately. PRIMARY AND SECONDARY OUTCOME MEASURES: Prehospital delay defined as hospital arrival ≥4-hour after stroke onset, poor hospital outcomes (in-hospital mortality and discharge to a nursing facility) and the opportunities of intravenous recombinant tissue plasminogen activator (rt-PA) and endovascular reperfusion therapy. RESULTS: In the overall cohort, prehospital delay was observed in 6373 (66%) patients. Among individuals residing in non-capital areas, those living in municipalities with higher ADI (more deprived) carried a significantly higher risk of prehospital delay (per one-point increase, OR (95% CI) 1.45 (1.26 to 1.66)) by multivariable logistic regression analysis. In-hospital mortality (1.45 (1.02 to 2.06)), discharge to a nursing facility (1.31 (1.03 to 1.66)), and delayed candidate arrival ≥2-hour of intravenous rt-PA (2.04 (1.30 to 3.26)) and endovascular reperfusion therapy (2.27 (1.06 to 5.00)), were more likely to be observed in the deprived areas with higher ADI. In the capital areas, postal-code-ADI was not associated with prehospital delay (0.97 (0.66 to 1.41)). CONCLUSIONS: Living in socioeconomically disadvantaged municipalities was associated with prehospital delays of acute ischaemic stroke in non-capital areas in Kochi prefecture, Japan. Poorer outcomes of those patients may be caused by delayed treatment of intravenous rt-PA and endovascular reperfusion therapy. Further studies are necessary to determine social risk factors in the capital areas. TRIAL REGISTRATION NUMBER: This article is linked to a clinical trial to UMIN000050189, No.: R000057166 and relates to its Result stage.


Subject(s)
Brain Ischemia , Emergency Medical Services , Ischemic Stroke , Stroke , Humans , Stroke/therapy , Retrospective Studies , Japan/epidemiology , Brain Ischemia/therapy , Tissue Plasminogen Activator , Social Class
2.
J Stroke Cerebrovasc Dis ; 27(8): 2134-2140, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29622372

ABSTRACT

BACKGROUND: Currently there are no pharmacological therapies for patients with unruptured cerebral aneurysms. Elsewhere we showed that the mineralocorticoid receptor antagonist eplerenone prevented the formation of cerebral aneurysms in our ovariectomized hypertensive aneurysm rat model. The current pilot study evaluated whether it can be used to prevent the growth and rupture of cerebral aneurysms in hypertensive patients. METHODS: Between August 2011 and May 2014, we enrolled 82 patients with 90 aneurysms in an open-label uncontrolled clinical trial. All provided prior informed consent for inclusion in this study, and all were treated with eplerenone (25-100 mg/d). The primary end points of our study were the rupture and enlargement of the cerebral aneurysms. RESULTS: Of the 82 patients, 80 (88 unruptured aneurysms) were followed for a mean of 21.3 months (153.4 aneurysm-years); 12 patients (15.0%) permanently discontinued taking the drug. One month after the start of eplerenone administration and throughout the follow-up period, eplerenone kept the blood pressure within the normal range. Most notably, no aneurysms smaller than 9 mm ruptured or enlarged. However, of 2 large thrombosed aneurysms, 1 enlarged and the other ruptured. The overall annual rupture rate was .65%; it was 13.16% for aneurysms larger than 10 mm; the overall annual rate for reaching the primary end points was 1.30%. CONCLUSION: Our observations suggest that eplerenone may help to prevent the growth and rupture of unruptured cerebral aneurysms smaller than 9 mm. To assess its potential long-term clinical benefits, large clinical trials are needed.


Subject(s)
Intracranial Aneurysm/drug therapy , Mineralocorticoid Receptor Antagonists/therapeutic use , Neuroprotective Agents/therapeutic use , Spironolactone/analogs & derivatives , Aged , Aneurysm, Ruptured/diagnostic imaging , Aneurysm, Ruptured/prevention & control , Brain/diagnostic imaging , Disease Progression , Eplerenone , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnostic imaging , Male , Mineralocorticoid Receptor Antagonists/adverse effects , Neuroprotective Agents/adverse effects , Pilot Projects , Spironolactone/adverse effects , Spironolactone/therapeutic use , Treatment Outcome
3.
J Neurosurg ; 128(1): 222-228, 2018 01.
Article in English | MEDLINE | ID: mdl-28156246

ABSTRACT

OBJECTIVE Aging of the population may lead to epidemiological changes with respect to chronic subdural hematoma (CSDH). The objectives of this study were to elucidate the current epidemiology and changing trends of CSDH in Japan. The authors analyzed patient information based on reports using a Japanese administrative database associated with the diagnosis procedure combination (DPC) system. METHODS This study included patients with newly diagnosed CSDH who were treated in hospitals participating in the DPC system. The authors collected data from the administrative database on the following clinical and demographic characteristics: patient age, sex, and level of consciousness on admission; treatment procedure; and outcome at discharge. RESULTS A total of 63,358 patients with newly diagnosed CSDH and treated in 1750 DPC participation hospitals were included in this study. Analysis according to patient age showed that the most common age range for these patients was the 9th decade of life (in their 80s). More than half of patients 70 years old or older presented with some kind of disturbance of consciousness. Functional outcomes at discharge were good in 71.6% (modified Rankin Scale [mRS] score 0-2) of cases and poor in 28.4% (mRS score 3-6). The percentage of poor outcomes tended to be higher in elderly patients. Approximately 40% of patients 90 years old or older could not be discharged to home. The overall recurrence rate for CSDH was 13.1%. CONCLUSIONS This study shows a chronological change in the age distribution of CSDH among Japanese patients, which may be affecting the prognosis of this condition. In the aging population of contemporary Japan, patients in their 80s were affected more often than patients in other age categories, and approximately 30% of patients with CSDH required some help at discharge. CSDH thus may no longer have as good a prognosis as had been thought.


Subject(s)
Hematoma, Subdural, Chronic/epidemiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Consciousness Disorders/epidemiology , Consciousness Disorders/therapy , Female , Hematoma, Subdural, Chronic/therapy , Humans , Infant , Infant, Newborn , International Cooperation , Japan/epidemiology , Male , Middle Aged , Recurrence , Retrospective Studies , Young Adult
4.
Transl Stroke Res ; 9(3): 306-316, 2018 06.
Article in English | MEDLINE | ID: mdl-29110250

ABSTRACT

Neurogenesis is essential for a good post-stroke outcome. Exogenous stem cells are currently being tested to promote neurogenesis after stroke. Elsewhere, we demonstrated that treatment with the PPARγ agonist pioglitazone (PGZ) before cerebral ischemia induction reduced brain damage and activated survival-related genes in ovariectomized (OVX) rats. Here, we tested our hypothesis that post-ischemia treatment with PGZ inhibits brain damage and contributes to neurogenesis via activated stem cells. Bone marrow (BM) cells of 7-week-old Wistar female rats were replaced with BM cells from green fluorescent protein-transgenic (GFP+BM) rats. Three weeks later, they were ovariectomized (OVX/GFP+BM rats). We subjected 7-week-old Wistar male and 13-week-old OVX/GFP+BM rats to 90-min cerebral ischemia. Male and OVX/GFP+BM rats were divided into two groups, one was treated with PGZ (2.5 mg/kg/day) and the other served as the vehicle control (VC). In both male and OVX/GFP+BM rats, post-ischemia treatment with PGZ reduced neurological deficits and the infarct volume. In male rats, PGZ decreased the mRNA level of IL-6 and M1-like macrophages after 24 h. In OVX/GFP+BM rats, PGZ augmented the proliferation of resident stem cells in the subventricular zone (SVZ) and the recruitment of GFP+BM stem cells on days 7-14. Both types of proliferated stem cells migrated from the SVZ into the peri-infarct area. There, they differentiated into mature neurons, glia, and blood vessels in association with activated Akt, MAP2, and VEGF. Post-ischemia treatment with PGZ may offer a new avenue for stroke treatment through contribution to neuroprotection and neurogenesis.


Subject(s)
Bone Marrow Cells/drug effects , Brain Ischemia/drug therapy , Neural Stem Cells/drug effects , Neurogenesis/drug effects , Neuroprotective Agents/pharmacology , PPAR gamma/agonists , Stroke/drug therapy , Thiazolidinediones/pharmacology , Animals , Disease Models, Animal , Female , Male , Neuroprotective Agents/administration & dosage , Pioglitazone , Rats , Rats, Wistar , Thiazolidinediones/administration & dosage
5.
Neurol Med Chir (Tokyo) ; 58(2): 85-90, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-29199247

ABSTRACT

Indocyanine green (ICG) emits fluorescence in the far-red domain under light excitation. ICG video angiography (ICG-VA) has been established as a useful method to evaluate blood flow in the operative field. We report the usefulness of ICG-VA for Sylvian fissure dissection in patients with subarachnoid hemorrhage (SAH). Subjects comprised 7 patients who underwent ICG-VA before opening the Sylvian fissure during neck clipping for ruptured cerebral aneurysm. We observed contrasted Sylvian veins before opening the Sylvian fissure using surgical microscopes. This procedure was termed "Sylvian ICG". We observed ICG fluorescence quickly in all cases. Sylvian veins that appeared unclear in the standard microscopic operative field covered with subarachnoid hemorrhage were extremely clearly depicted. These Sylvian ICG findings were helpful in identifying entry points and the dissecting course of the Sylvian fissure. At the time of clipping, no residual fluorescence from Sylvian ICG was present, and aneurysm clipping was not impeded. Sylvian ICG for SAH patients is a novel technique to facilitate dissection of the Sylvian fissure. We believe that this technique will contribute to improved safety of clipping surgery for ruptured aneurysms.


Subject(s)
Cerebral Angiography , Cerebral Veins/diagnostic imaging , Dissection/methods , Indocyanine Green , Subarachnoid Hemorrhage/diagnostic imaging , Surgery, Computer-Assisted/methods , Aged , Aneurysm, Ruptured/complications , Aneurysm, Ruptured/diagnostic imaging , Aneurysm, Ruptured/surgery , Cerebral Veins/surgery , Coloring Agents , Female , Humans , Intracranial Aneurysm/complications , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Male , Middle Aged , Subarachnoid Hemorrhage/etiology , Subarachnoid Hemorrhage/surgery
7.
J Neuroinflammation ; 13(1): 165, 2016 06 27.
Article in English | MEDLINE | ID: mdl-27349749

ABSTRACT

BACKGROUND: Hyperhomocysteinemia (HHcy) is associated with inflammation and a rise in the expression of matrix metalloproteinase-9 (MMP-9) in the vascular wall. However, the role of HHcy in the growth and rupture of cerebral aneurysms remains unclear. METHODS: Thirteen-week-old female Sprague-Dawley rats were subject to bilateral ovariectomy and ligation of the right common carotid artery and fed an 8 % high-salt diet to induce cerebral aneurysms. Two weeks later, they underwent ligation of the bilateral posterior renal arteries. They were divided into two groups and methionine (MET) was or was not added to their drinking water. In another set of experiments, the role of folic acid (FA) against cerebral aneurysms was assessed. RESULTS: During a 12-week observation period, subarachnoid hemorrhage due to aneurysm rupture was observed at the anterior communicating artery (AcomA) or the posterior half of the circle of Willis. HHcy induced by excessive MET intake significantly increased the incidence of ruptured aneurysms at 6-8 weeks. At the AcomA of rats treated with MET, we observed the promotion of aneurysmal growth and infiltration by M1 macrophages. Furthermore, the mRNA level of MMP-9, the ratio of MMP-9 to the tissue inhibitor of metalloproteinase-2, and the level of interleukin-6 were higher in these rats. Treatment with FA abolished the effect of MET, suggesting that the inflammatory response and vascular degradation at the AcomA is attributable to HHcy due to excessive MET intake. CONCLUSIONS: We first demonstrate that in hypertensive ovariectomized rats, HHcy induced by excessive MET intake may be associated with the propensity of the aneurysm wall to rupture.


Subject(s)
Aneurysm, Ruptured , Folic Acid/therapeutic use , Hyperhomocysteinemia/chemically induced , Methionine/toxicity , Vitamin B Complex/therapeutic use , Aneurysm, Ruptured/complications , Aneurysm, Ruptured/etiology , Aneurysm, Ruptured/pathology , Aneurysm, Ruptured/prevention & control , Animals , Arteries/pathology , Arteries/ultrastructure , Blood Pressure/drug effects , Cysteine/blood , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Female , Hyperhomocysteinemia/physiopathology , Matrix Metalloproteinase 9/metabolism , NADPH Oxidase 4 , NADPH Oxidases/metabolism , Ovariectomy , Rats , Rats, Sprague-Dawley , Subarachnoid Hemorrhage/etiology , Tissue Inhibitor of Metalloproteinase-1/metabolism , Tissue Inhibitor of Metalloproteinase-2/metabolism
8.
Case Rep Neurol Med ; 2016: 9108641, 2016.
Article in English | MEDLINE | ID: mdl-28074165

ABSTRACT

Background and Importance. Subependymoma occurs very rarely in the spinal cord. We report another case of spinal subependymoma along with a review of the literature and discussion of a radiological finding that is useful for preoperative diagnosis of this tumor. Clinical Presentation. A 51-year-old man presented with a 2-year history of progressive muscle weakness in the right lower extremity. Sagittal magnetic resonance imaging (MRI) showed spinal cord expansion at the Th7-12 vertebral level. Surgical resection was performed and the tumor was found to involve predominantly subpial growth. Histological diagnosis was subependymoma, classified as Grade I according to criteria of World Health Organization. We made an important discovery of what seems to be a characteristic appearance for spinal subependymoma on sagittal MRI. Swelling of the spinal cord is extremely steep, providing unusually large fusiform dilatation resembling a bamboo leaf. We have termed this characteristic MRI appearance as the "bamboo leaf sign." This characteristic was apparent in 76.2% of cases of spinal subependymoma for which MRI findings were reported. Conclusion. The bamboo leaf sign on spinal MRI is useful for differentiating between subependymoma and other intramedullary tumors. Neurosurgeons encountering the bamboo leaf sign on spinal MRI should consider the possibility of subependymoma.

9.
Brain Res ; 1616: 37-44, 2015 Aug 07.
Article in English | MEDLINE | ID: mdl-25957792

ABSTRACT

Estrogen deficiency worsens ischemic stroke outcomes. In ovariectomized (OVX(+)) rats fed a high-salt diet (HSD), an increase in the body Na(+)/water ratio, which characterizes water-free Na(+) accumulation, was associated with detrimental vascular effects independent of the blood pressure (BP). We hypothesized that an increase in brain water-free Na(+) accumulation is associated with ischemic brain damage in OVX(+)/HSD rats. To test our hypothesis we divided female Wistar rats into 4 groups, OVX(+) and OVX(-) rats fed HSD or a normal diet (ND), and subjected them to transient cerebral ischemia. The brain Na(+)/water ratio was increased even in OVX(+)/ND rats and augmented in OVX(+)/HSD rats. The increase in the brain Na(+)/water ratio was positively correlated with expansion of the cortical infarct volume without affecting the BP. Interestingly, OVX(+) was associated with the decreased expression of ATP1α3, a subtype of the Na(+) efflux pump. HSD increased the expression of brain Na(+) influx-related molecules and the mineralocorticoid receptor (MR). The pretreatment of OVX(+)/HSD rats with the MR antagonist eplerenone reduced brain water-free Na(+) accumulation, up-regulated ATP1α3, down-regulated MR, and reduced the cortical infarct volume. Our findings show that the increase in the brain Na(+)/water ratio elicited by estrogen deficiency or HSD is associated with ischemic brain damage BP-independently, suggesting the importance of regulating the accumulation of brain water-free Na(+). The up-regulation of ATP1α3 and the down-regulation of MR may provide a promising therapeutic strategy to attenuate ischemic brain damage in postmenopausal women.


Subject(s)
Blood Pressure/physiology , Brain/metabolism , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/pathology , Sodium/metabolism , Analysis of Variance , Animals , Disease Models, Animal , Female , Gene Expression Regulation/physiology , Ovariectomy , RNA, Messenger/metabolism , Rats , Rats, Wistar , Receptors, Mineralocorticoid/genetics , Receptors, Mineralocorticoid/metabolism , Sodium-Potassium-Exchanging ATPase/genetics , Sodium-Potassium-Exchanging ATPase/metabolism , Water/chemistry , Water/metabolism
10.
J Neurosurg ; 123(4): 1065-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25909568

ABSTRACT

OBJECT: Endoscopic surgery was performed for acute or subacute subdural hematoma (SDH), and its effectiveness and safety in elderly patients were evaluated. METHODS: Between September 2007 and November 2013, endoscopic surgery was performed in 11 elderly patients with acute SDH (8 patients) and subacute SDH (3 patients). The criteria for surgery were as follows: 1) the presence of clinical symptoms; 2) age older than 70 years; 3) no brain injury (intracerebral hematoma, brain contusion); 4) absence of an enlarging SDH; and 5) no high risk of bleeding. Hematoma evacuation was performed with a 4-mm rigid endoscope with a 0° lens and a malleable irrigation suction cannula. RESULTS: Endoscopic surgery was performed under local anesthesia. The mean age of the patients was 82.6 years (range 73-91 years). There were 5 female and 6 male patients. The mean preoperative Glasgow Coma Scale score was 12, and 5 patients had been receiving antithrombotic drug therapy. The mean operation time was 85 minutes. Only 1 patient had rebleeding, and reoperation with the same technique was performed uneventfully in this individual. A total of 7 patients had a good recovery (modified Rankin Scale Score 0-2) at discharge. CONCLUSIONS: Endoscopic hematoma evacuation of acute and subacute SDH is a safe and effective method of clot removal that minimizes operative complications. This technique may be a less invasive method for treating elderly patients with acute and subacute SDHs.


Subject(s)
Endoscopy , Hematoma, Subdural, Acute/surgery , Aged , Aged, 80 and over , Female , Humans , Male , Retrospective Studies , Treatment Outcome
11.
J Stroke Cerebrovasc Dis ; 24(7): 1487-92, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25891757

ABSTRACT

BACKGROUND: Managing hypertension is crucial for preventing stroke recurrence. Some stroke patients experience resistant hypertension. In our experimental stroke model, olmesartan increased the expression of angiotensin (Ang) II converting enzyme-2. We hypothesized that switching to olmesartan affects biomarkers and the blood pressure (BP) in stroke patients whose BP is insufficiently controlled by standard doses of Ang II type I receptor blockers (ARBs) other than olmesartan. METHODS: We recruited 25 patients to study our hypothesis. All had a history of stroke or silent cerebral infarction. We switched them to olmesartan (10-40 mg per day) for 12 weeks and determined their plasma level of Ang-(1-7), peroxiredoxin, oxidized low-density lipoprotein (oxLDL)/ß-2-glycoprotein I (ß2GPI) complex, adiponectin, high mobility group box 1 (HMGB1), and tumor necrosis factor-α (TNFα) and recorded their BP before and after olmesartan treatment. RESULTS: After switching the patients to olmesartan, their plasma level of Ang-(1-7) as a vasoprotective indicator and adiponectin regulating metabolic syndrome was increased, and peroxiredoxin and the oxLDL/ß2GPI complex indicating its antioxidative stress and its proatherogenicity were lower than their baseline. This suggests that olmesartan may be more effective than other ARBs to improve these conditions. Neither HMGB1 nor TNFα reflecting an inflammatory response was affected, suggesting that the anti-inflammatory effects of olmesartan are similar to those of other ARBs. The recommended BP (<140/90) was obtained in 10 of the 25 patients after switching to olmesartan. No adverse events occurred. CONCLUSIONS: Switching from other ARBs to olmesartan may be a promising therapeutic option in patients with resistant hypertension.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Antihypertensive Agents/therapeutic use , Biomarkers/blood , Drug Substitution , Hypertension/drug therapy , Olmesartan Medoxomil/therapeutic use , Stroke/drug therapy , Aged , Angiotensin I/blood , Angiotensin II Type 1 Receptor Blockers/adverse effects , Antihypertensive Agents/adverse effects , Blood Pressure/drug effects , Female , Humans , Hypertension/blood , Hypertension/diagnosis , Hypertension/physiopathology , Japan , Lipoproteins, LDL/blood , Male , Middle Aged , Olmesartan Medoxomil/adverse effects , Peptide Fragments/blood , Peroxiredoxins/blood , Prospective Studies , Stroke/blood , Stroke/diagnosis , Stroke/physiopathology , Time Factors , Treatment Outcome , beta 2-Glycoprotein I/blood
12.
Surg Neurol Int ; 5: 88, 2014.
Article in English | MEDLINE | ID: mdl-25024888

ABSTRACT

BACKGROUND: Chronic encapsulated intracerebral hematoma (CEIH) is one type of intracerebral hematoma that sometimes grows progressively while forming a capsule and presenting with neurological deficits. Although many cases of CEIH have been reported, correct preoperative diagnosis is very difficult. Only around 20% of cases are diagnosed preoperatively. CASE DESCRIPTION: We encountered three cases of CEIH in which causes were unidentified and difficult to diagnose. All three cases were treated surgically. In the first case, a 59-year-old male was diagnosed preoperatively with metastatic brain tumor. In the second case, a 62-year-old female was diagnosed preoperatively with glioblastoma. The third case involved a 58-year-old female diagnosed preoperatively with CEIH. CONCLUSION: We should keep in mind that CEIH is a differential diagnosis for intracerebral space-occupying lesions. This report describes these three cases and discusses imaging findings and characteristics of CEIH.

13.
Hypertension ; 60(5): 1309-15, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23045463

ABSTRACT

The incidence of cerebral aneurysms is higher in women than in men, especially postmenopause. Although hypertension is thought to be associated with a high incidence of stroke, not all patients with unruptured cerebral aneurysms are hypertensive. The possibility of water-free Na(+) storage associated with hypertension has been raised. However, whether the increase in the body Na(+)/water ratio that characterizes water-free Na(+) accumulation is associated with the formation of cerebral aneurysms remains obscure. To examine this relationship, Sprague-Dawley female rats subjected to carotid artery ligation were divided into 3 groups: a high-salt diet group (HSD) without and another with bilateral oophorectomy (HSD/OVX) and a third group that underwent additional renal artery ligation (HSD/OVX/RL). Compared with rats receiving a normal diet (shams), water retention was increased in HSD rats but not in HSD/OVX rats. Interestingly, compared with HSD rats, the incidence of cerebral aneurysms and the body Na(+)/water ratio were significantly higher in HSD/OVX and HSD/OVX/RL rats, independent of hypertension. In their aneurysmal wall, ATP1α2, a subtype of Na(+)/K(+)-ATPase, was downregulated, whereas inflammatory-related molecules were upregulated. Treatment with low-dose olmesartan that did not affect the blood pressure in hypertensive HSD/OVX/RL rats reduced the rate of cerebral aneurysm formation, body Na(+) retention, and the Na(+)/water ratio and upregulated ATP1α2. These results suggest that the increase in the Na(+)/water ratio and a reduction in ATP1α2 may be associated with cerebral aneurysm formation. We provide the new insight that the management of water-free Na(+) is important to prevent their development.


Subject(s)
Body Water/metabolism , Intracranial Aneurysm/metabolism , Ovariectomy , Sodium/metabolism , Angiotensin II Type 1 Receptor Blockers/pharmacology , Animals , Blood Pressure/drug effects , Blotting, Western , Carotid Arteries/surgery , Female , Humans , Hypertension/drug therapy , Hypertension/metabolism , Hypertension/physiopathology , Imidazoles/pharmacology , Intracranial Aneurysm/physiopathology , Intracranial Aneurysm/prevention & control , Ligation , Rats , Rats, Sprague-Dawley , Renal Artery/surgery , Sodium Chloride, Dietary/administration & dosage , Sodium-Potassium-Exchanging ATPase/metabolism , Tetrazoles/pharmacology , Up-Regulation/drug effects , Water-Electrolyte Balance
14.
Stroke ; 43(2): 478-83, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22076002

ABSTRACT

BACKGROUND AND PURPOSE: The role of the phosphorylated signal transducer and activator of transcription-3 (p-STAT3) after cerebral ischemia by the peroxisome proliferator-activated receptor γ (PPARγ) agonist pioglitazone (PGZ) remains controversial. Whether the increase in p-STAT3 by estrogen is mediated by the estrogen receptor α is also obscure. We examined the role of p-STAT3, PPARγ, and estrogen receptor α against ischemic brain damage after PGZ treatment. METHODS: Female Wistar rats subjected or not subjected to bilateral oophorectomy were injected with 1.0 or 2.5 mg/kg PGZ 2 days, 1 day, and 1 hour before 90-minute middle cerebral artery occlusion-reperfusion and compared with vehicle-control rats. RESULTS: The cortical infarct size was larger in ovariectomized than in nonovarietomized rats; it was reduced by PGZ treatment. Inversely with the reduction of the infarct size, PPARγ, and p-STAT3 but not estrogen receptor α in the peri-infarct area were increased in PGZ-treated compared with vehicle-control rats. The increase in PPARγ and p-STAT3 was associated with the transactivation of antiapoptotic and survival genes and the reduction of caspase-3 in this area. Inhibitors of PPARγ or STAT3 abolished the PGZ-induced neuroprotection and the increase in p-STAT3. More importantly, p-STAT3 increased by PGZ was bound to PPARγ and the complex translocated to the nucleus to dock to the response element through p-STAT3. CONCLUSIONS: Our findings suggest that the activation in the peri-infarct region of p-STAT3 and PPARγ by PGZ is essential for neuroprotection after ischemia and that PGZ may be of benefit even in postmenopausal stroke patients.


Subject(s)
Brain Ischemia/drug therapy , Cerebral Infarction/drug therapy , Neuroprotective Agents , Ovariectomy , PPAR gamma/agonists , STAT3 Transcription Factor/genetics , STAT3 Transcription Factor/metabolism , Thiazolidinediones/therapeutic use , Animals , Apoptosis/genetics , Basal Ganglia/pathology , Brain/pathology , Brain Ischemia/pathology , Caspase 3/metabolism , Cell Nucleus/metabolism , Cerebral Infarction/pathology , DNA/genetics , Estrogen Receptor alpha/metabolism , Female , Pioglitazone , Protein Transport , Rats , Rats, Wistar , Response Elements , Transcriptional Activation/drug effects
15.
Stroke ; 42(8): 2286-93, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21737796

ABSTRACT

BACKGROUND AND PURPOSE: The pathogenesis of cerebral aneurysms is linked to inflammation, degradation of the extracellular matrix, and vascular wall apoptosis. Statins exert pleiotropic effects on the vasculature, independent of their cholesterol-lowering properties. To explore the detailed pathogenesis of cerebral aneurysms, we examined their progression in a rat model and studied whether statins prevent their initiation and growth. METHODS: Cerebral aneurysms were induced in female rats subjected to hypertension, increased hemodynamic stress, and estrogen deficiency. The development of aneurysm was assessed morphologically on corrosion casts. The effects of pravastatin (5, 25, or 50 mg/kg per day) and of simvastatin (5 mg/kg per day) on their aneurysms were studied. Human brain endothelial cells were also used to determine the effects of pravastatin. RESULTS: Pravastatin (5 mg/kg per day) reduced endothelial damage and inhibited aneurysm formation; there was an association with increased endothelial nitric oxide synthase (eNOS) levels and a decrease in human brain endothelial cell adhesion molecules. Unexpectedly, 25 mg/kg per day and 50 mg/kg per day pravastatin and 5 mg/kg per day simvastatin promoted aneurysmal growth, and high-dose pravastatin induced aneurysmal rupture. The deleterious effects exerted by these statins were associated with an increase in apoptotic caspase-3 levels and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells, suggesting that statins exert bidirectional effects. CONCLUSIONS: Our results provide the first evidence that cerebral aneurysm growth is partly associated with apoptosis and issue a warning that statins exert bidirectional effects on cerebral aneurysms. Additional intensive research is necessary to understand better their mechanisms and to identify patients in whom the administration of statins may elicit deleterious effects.


Subject(s)
Brain/drug effects , Brain/pathology , Estrogens/deficiency , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Intracranial Aneurysm/pathology , Pravastatin/pharmacology , Simvastatin/pharmacology , Animals , Apoptosis , Cells, Cultured , Disease Models, Animal , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Endothelial Cells/pathology , Female , Humans , Hypertension/complications , Hypertension/metabolism , Hypertension/pathology , Intracranial Aneurysm/etiology , Intracranial Aneurysm/metabolism , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Sprague-Dawley
16.
J Hypertens ; 28(9): 1883-91, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20577123

ABSTRACT

OBJECTIVE: The formation of cerebral aneurysms is associated with endothelial damage and macrophage migration. Hypothesizing that the opening of tight junctions due to the disappearance of the tight junction proteins occludin and zona occludens-1 (ZO-1) in damaged endothelia allows macrophage migration, leading to cerebral aneurysm formation, we investigated the role of tight junction proteins. METHODS: The vascular wall of female rats subjected to hypertension, oophorectomy (OVX), and hemodynamic stress to induce cerebral aneurysms was evaluated morphologically, immunohistochemically, and by quantitative RT-PCR. We also assessed the regulation of tight junction proteins in human brain endothelial cells (HBECs). RESULTS: In the very early stage before aneurysm formation, the expression of occludin and ZO-1 was reduced in injured endothelial cell junctions exhibiting gaps. In the course of aneurysmal progression their reduction progressed and was correlated with macrophage migration. In hypertension along with OVX rats we observed an increase in angiotensin II and the degradation molecules matrix metalloproteinase-9 (MMP-9), nicotinamide-adenine dinucleotide phosphate oxidases and monocyte chemoattractant protein-1. The mineralocorticoid receptor blocker eplerenone increased occludin and ZO-1 expression; this was associated with a reduction in angiotensin II and the degradation molecules and resulted in the inhibition of macrophage exudation and aneurysm formation. In HBECs, occludin and ZO-1 downregulation by angiotensin II and estrogen deficiency was reversed by eplerenone, the MMP inhibitor SB3CT, and apocynin. Our results suggest that macrophage migration is associated with the reduction in tight junction proteins induced by the degradation molecules. CONCLUSION: In rats, the destruction of tight junctions may facilitate macrophage migration and cerebral-aneurysm formation.


Subject(s)
Intracranial Aneurysm/etiology , Intracranial Aneurysm/metabolism , Tight Junctions/metabolism , Animals , Base Sequence , Brain/metabolism , Cells, Cultured , Chemokine CCL2/genetics , Chemokine CCL2/metabolism , DNA Primers/genetics , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Endothelial Cells/pathology , Eplerenone , Female , Humans , Intracranial Aneurysm/genetics , Intracranial Aneurysm/pathology , Macrophages/metabolism , Macrophages/pathology , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Occludin , Phosphoproteins/genetics , Phosphoproteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Reactive Oxygen Species/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Spironolactone/analogs & derivatives , Spironolactone/pharmacology , Tight Junctions/drug effects , Tight Junctions/pathology , Zonula Occludens-1 Protein
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