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Objective To investigate the relationship between SAP97 genetic polymorphisms and sporadic Parkinson's disease (PD) in Han Chinese population with the expectation of offering genetic data for the early prevention and treatment of the disease. Methods In this study, we genotyped single-nucleotide polymorphisms (SNPs) (rs3915512 and rs9843659) in theSAP97 gene in 317 patients with PD and 317 healthy-matched controls in a Han Chinese population through the improved multiplex ligation detection reaction (imLDR) technique. Then, we analyzed the association of each SNP, alone or in combination, with risk or age of onset of PD. Results The SAP97 rs3915512 and rs9843659 polymorphisms were not associated with the risk of PD. However, the minor allele of the rs3915512 and rs9843659 were significantly more common in PD patients with an early age of onset. Additionally, significant differences in the distribution of the onset age of the PD among different genotypes of the rs9843659 polymorphism. The CA haplotype was significantly related to early onset PD. Conclusions Our data are the first to suggest that the SAP97 SNPs rs3915512 and rs9843659 and the CA haplotype may be significantly associated with early onset PD in China.

Endothelial microvesicles (EMVs) could reflect the status of endothelial cells (ECs) which are involved in the pathogenesis of ischemic stroke (IS). MiR-155 could regulate EC functions. However, their roles in IS remain unclear. This study aimed to investigate the levels of plasma EMVs and EMVs carrying miRNA-155 (EMVs-miR-155) in IS patients to explore their potential roles as biomarkers. Ninety-three IS patients and 70 controls were recruited in this study. The levels of circulating EMVs and EMVs-miR-155 were detected by fluorescence nanoparticle tracking analysis and quantitative real-time PCR, respectively. The correlations between level of EMVs/EMVs-miR-155 and the onset time, severity, infarct volume, and subtypes of IS were analyzed. The severity and infarct volume were assessed by NIHSS and magnetic resonance imaging, respectively. Multivariate logistic regression analysis was used to investigate the risk factors of IS. The ROC curve and area under ROC curve (AUC) of EMVs and EMVs-miR-155 were determined. The levels of plasma EMVs and EMVs-miR-155 were increased significantly in acute and subacute stages of IS and remained unchanged in chronic stage, and were positively related to the infarct volume and NIHSS scores and were associated with large artery atherosclerosis and cardioembolism subtypes defined by Trial of Org 10 172 in acute stroke treatment (TOAST) classification. Multivariate logistic regression analysis demonstrated that plasma EMVs and EMVs-miR-155 were significant and independent risk factors of IS and their AUC were 0.778 and 0.851, respectively, and increased to 0.892 after combination. Our study suggests that plasma EMVs and EMVs-miR-155 are promising biomarkers for IS. The diagnostic value of EMVs-miR-155 is higher and their combination is the best.

The identification of new biomarkers (e.g., metabolic biomarkers) will facilitate not only the diagnosis of stroke but also the differentiation of stroke subtypes, especially the discrimination of ischaemic stroke from intracerebral hemorrhage. Herein, we develop for the first time an ultra-high-pressure liquid chromatography tandem mass spectrometry (UHPLC-MS)-based targeted metabolomic method to screen the metabolic biomarkers of stroke and identify the fatty acid metabolite 20-hydroxy-leukotriene B4 (20-OH-LTB4) and its key enzyme cytochrome P450 family 4 subfamily F member 2 (CYP4F2) as the potential biomarkers for differentiating healthy persons, acute ischemic stroke (AIS) patients, and intracerebral hemorrhage stroke (ICH) patients. We evaluated 158 fatty acids and their metabolites in 177 serum samples obtained from 65 healthy volunteers, 70 AIS patients and 42 ICH patients, and identified the potential biomarkers associated with ICH by using multivariate statistical analysis. We found that 20-OH-LTB4 and arachidonic acid can be used to discriminate ICH patients from healthy individuals, and 20-OH-LTB4 and 17, 18-epoxy-eicosatetraenoic acid (7,18-EpETE) can be used to differentiate the subtypes of ICH and AIS. Especially, 20-OH-LTB4 may function as a potential biomarker for ICH diagnosis and risk assessment, and it can discriminate ICH patients from healthy individuals and AIS patients. Moreover, we identified CYP4F2 protein as a potential biomarker of ICH for prevention and treatment assessment. This method may provide a powerful platform for ICH diagnosis, prevention, and treatment assessment.

Angiotensin (Ang)-(1-7) is a potential vasoprotective peptide. In the present study, we investigated its counteractive effects to Ang II on vascular smooth muscle cells (VSMCs) and intracerebral hemorrhagic stroke (ICH) through inflammatory mechanism. In in vitro experiments, human brain VSMCs (HBVSMCs) were treated with vehicle, Ang II, Ang II + Ang-(1-7), Ang II + A-779 or Ang II + Ang-(1-7) + A-779 (Mas receptor antagonist). HBVSMC proliferation, migration and apoptosis were determined by methyl thiazolyltetrazolium, wounding healing assay and flow cytometry, respectively. In in vivo experiments,C57BL/6 mice were divided into vehicle, Ang II, Ang II + Ang-(1-7), Ang II + A-779 or Ang II + Ang-(1-7) + A-779 groups before they were subjected to collagenase-induced ICH or sham surgery. Hemorrhage volume and middle cerebral artery (MCA) remodeling were determined by histological analyses. Levels of NFκB, Inhibitor of κBα (IκBα), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein 1 (MCP-1) and interleukin (IL-8) were measured by western blot or ELISA. We found that 1) Ang II increased HBVSMC migration, proliferation and apoptosis, and increased the blood pressure (BP), neurological deficit score, MCA remodeling and hemorrhage volume in ICH mice. 2) Ang-(1-7) counteracted these effects of Ang II, which was independent of BP, with the down-regulation of NFκB, up-regulation of IκBα, and decreased levels of TNF-α, MCP-1 and IL-8. 3) The beneficial effects of Ang-(1-7) could be abolished by A-779. In conclusion, Ang-(1-7) counteracts the effects of Ang II on ICH via modulating NFκB inflammation pathway in HBVSMCs and cerebral microvessels.

Thrombin-activatable fibrinolysis inhibitor (TAFI) was reported as an anaphylatoxin-inactivating enzyme generated by proteolytic cleavage of its zymogen, and is the same enzyme as that first designated by our group as procarboxypeptidase R (proCPR). Its level in plasma appears to influence vascular disease. In addition, TAFI activity is strongly influenced by genetic polymorphism, especially at amino acids 147 and 325. We investigated whether these TAFI polymorphisms would act as a risk factor for cerebral infarction (CI) by examining 253 samples in which the diagnosis was cliniconeuropathologically confirmed. We found little that was statistically significant in terms of these polymorphisms among patients with no vascular problems or in a population-based control group. In the present study of an elderly Japanese group, our samples revealed a lower percentage of the Ile allele at Thr/Ile-325 compared with western counterparts. Although patients with severe infarcts had a lower percentage of the Ile allele (10%) at amino acid position 325 compared with the slightly and moderately affected patients and the population-based control group (15-18%), no statistical significance was found. None of our results showed any statistical correlation between TAFI polymorphisms and CI.

Fibroblast growth factor 1 (FGF1, also known as acidic FGF) protects selective neuronal populations against neurotoxic effects such as those in Alzheimer’s disease (AD) and HIV encephalitis. The FGF1 gene is therefore a strong candidate gene for AD. Using the promoter polymorphism of the FGF1 gene, we examined the relationship between AD and the FGF1 and apolipoprotein E (APOE) genes in 100 Japanese autopsy-confirmed late-onset AD patients and 106 age-matched non-demented controls. The promoter polymorphism (−1385 A/G) was significantly associated with AD risk. The odds ratio for AD associated with the GG vs non-GG genotype was 2.02 (95% CI = 1.16−3.52), while that of e4 vs non-e4 in APOE4 gene was 5.19 (95% CI = 2.68−10.1). The odds ratio for APOEe4 and FGF1 GG carriers was 20.5 (95% CI = 6.88−60.9). The results showed that the FGF1 gene is associated with autopsy-confirmed AD.

The β-adrenoceptor (β-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the α-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the β-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p =0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p =0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p =0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p =0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the β-AR-Gs protein system, and hypertension. (Hypertens Res 2003; 26: 439-444)

The renin-angiotensin system plays an important role in blood pressure regulation by influencing salt-water homeostasis and vascular tone. Angiotensin II, the major biologically active component of this system, exerts its effect via two pharmacologically distinct subtypes of angiotensin II receptors, the angiotensin II type 1 receptor (AT1-R) and the angiotensin II type 2 receptor (AT2-R). Thus, the AT2-R gene may be involved in hypertension. Accordingly, our objective was to examine whether polymorphisms of the AT2-R gene are involved in hypertension. The entire AT2-R gene including the promoter region was screened to find polymorphisms. As a result, two novel single nucleotide polymorphisms (SNPs), A1818T in intron 2 and G4303A in exon 3, as well as two known SNPs, A1675G in intron 1 and C4599A in exon 3, were identified. These four SNPs had similar allele frequencies, and the A1675G and C4599A polymorphisms were in almost complete linkage disequilibrium. Because the AT2-R gene is located on the X chromosome, we analyzed the possible association between the C4599A polymorphism and hypertension in men and in women separately in two large Japanese populations. This analysis showed that the C4599A polymorphism was associated with hypertension in women (p=0.0058), but not in men. Moreover, this female-specific association was pronounced in premenopausal women. The female-specific association may be helpful in conducting further molecular and biological studies on the relationship among sex, the renin-angiotensin system, and hypertension.

Hypertension is a common, complex phenotype resulting from the interaction between genetic and environmental factors. To select candidate regions potentially responsible for hypertension, we are conducting a genome-wide linkage disequilibrium (LD) mapping of hypertension using dinucleotide repeat markers in 146 hypertensive and 136 normotensive subjects. Although the LD mapping is still underway, 19 alleles of 15 markers have already shown a nominally significant association (p

Background Platelet activation and aggregation are critical in the pathogenesis of acute ischemic stroke (AIS). Circulating platelet microparticles (PMPs) and platelet parameters are biologic markers of platelet function in AIS patients; however, their associations with stroke subtypes and infarct volume remain unknown. Methods We recruited 112 AIS patients including large-artery atherosclerosis (LAA) and small-artery occlusion [SAO] subtypes and 35 controls in this study. Blood samples were collected at admission and after antiplatelet therapy. The levels of circulating PMPs and platelet parameters (mean platelet volume [MPV], platelet count, plateletocrit, and platelet distribution width) were determined by flow cytometry and hematology analysis, respectively. Infarct volume was examined at admission by magnetic resonance imaging. Results (1) The levels of circulating PMPs and MPV were significantly elevated in AIS patients compared with healthy controls; (2) the level of circulating PMPs, but not platelet parameters, was decreased after antiplatelet therapy in AIS patients; (3) the infarct volume in LAA subtype was larger than that in SAO subtype. Notably, circulating PMP level was positively correlated with the infarct volume in LAA subtype. No association with infarct volume in either AIS subtype was observed for platelet parameters; and (4) according to the regression analysis, circulating PMP was an independent risk factor for the infarct volume in pooled AIS patients after adjustments of other impact factors (hypertension and diabetes). Conclusions Our results suggest that circulating PMP level is associated with cerebral injury of AIS, which offers a novel evaluation parameter for AIS patients.

Circulating progenitor cells and stromal-derived factor-1alpha (SDF-1α) have been suggested to participate in tissue repair after ischemic injury. However, the predictive role of circulating CD133+ CD34+ progenitors and plasma SDF-1α in ischemic stroke (IS) patients remains unknown. In this study, we recruited 95 acute IS patients, 40 at-risk subjects, and 30 normal subjects. The National Institutes of Health Stroke Scale (NIHSS), infarct volume, and carotid intima-media thickness (IMT) were determined at day 1 and the modified Rankin scale (mRS) of functional outcome was assessed at day 21. The levels of circulating CD133+ CD34+ cells and plasma SDF-1α were determined by flow cytometry and enzyme-linked immunosorbent assay, respectively. Our data showed that: (1) the levels of CD133+ CD34+ cells were lower in at-risk subjects and IS patients at admission (day 1) when compared with normal controls; (2) the day 1 level of CD133+ CD34+ cells varied in IS subgroups and inversely correlated with NIHSS and carotid IMT and the level of SDF-1α inversely correlated with NIHSS and infarct volume; (3) the increment rates of circulating CD133+ CD34+ cells and plasma SDF-1α within the first week were correlated; and (4) patients with a higher level of CD133+ CD34+ cells at day 7 had a low mRS. The increased rate of CD133+ CD34+ cells in the first week was inversely associated with mRS. In conclusion, our findings demonstrate that the circulating CD133+ CD34+ progenitor cells and plasma SDF-1α can be used as predictive parameters for IS severity and outcome.

For determining the implications of circulating endothelial progenitor cells (cEPCs) and cellular membrane microparticles (MPs) in diabetic stroke, levels of EPCs, EPC-MPs, and endothelium-derived MPs (EMPs) and their correlations with blood glucose concentration, cerebral microvascular density (cMVD), and ischemic damage were investigated in type 2 diabetic db/db and db/+ (wild-type control) mice. Therapeutic efficacy of EPC infusion (preincubated with MPs) was also explored. Ischemic stroke was induced by middle cerebral artery occlusion (MCAO) surgery. Ischemic damage and cMVD were determined using histological analyses. The levels of cEPCs and MPs were determined using flow cytometric analyses. EPC generation and functions were evaluated by in vitro cell cultures. Results showed the following. 1) In db/db mice, the basal level of cEPCs was less and cMVDs were lower, but the levels of circulating EPC-MPs and EMPs were more; 2) MCAO induced a larger infarct volume and less of an increase in cEPCs in db/db mice; 3) the level of cEPCs correlated with blood glucose concentration (negatively), cMVD (positively), and ischemic damage (negatively), but the levels of EPC-MPs and EMPs correlated inversely with those parameters; 4) EPCs were reduced and dysfunctional in db/db mice, and preincubation with db/db MPs impaired EPC functions; and 5) infusion of EPCs preincubated with db/+ MPs increased the level of cEPCs and reduced ischemic damage, and these beneficial effects were reduced or lost in EPCs preincubated with db/db MPs. These data suggest that reduced cEPCs, impaired EPC generation/function, and increased production of MPs might be the mechanisms responsible for increased ischemic damage seen in db/db mice.