Lifen Chen

Meta-analysis comparing deep brain stimulation of the globus pallidus and subthalamic nucleus to treat advanced Parkinson disease

OBJECT Deep brain stimulation (DBS) is the surgical procedure of choice for patients with advanced Parkinson disease (PD). The globus pallidus internus (GPi) and the subthalamic nucleus (STN) are commonly targeted by this procedure. The purpose of this meta-analysis was to compare the efficacy of DBS in each region. METHODS MEDLINE/PubMed, EMBASE, Web of Knowledge, and the Cochrane Library were searched for English-language studies published before April 2013. RESULTS of studies investigating the efficacy and clinical outcomes of DBS of the GPi and STN for PD were analyzed. RESULTS Six eligible trials containing a total of 563 patients were included in the analysis. Deep brain stimulation of the GPi or STN equally improved motor function, measured by the Unified Parkinsons Disease Rating Scale Section III (UPDRSIII) (motor section, for patients in on- and off-medication phases), within 1 year postsurgery. The change score for the on-medication phase was 0.68 (95% CI - 2.12 to 3.47, p > 0.05; 5 studies, 518 patients) and for the off-medication phase was 1.83 (95% CI - 3.12 to 6.77, p > 0.05; 5 studies, 518 patients). The UPDRS Section II (activities of daily living) scores for patients on medication improved equally in both DBS groups (p = 0.97). STN DBS allowed medication dosages to be reduced more than GPi DBS (95% CI 129.27-316.64, p < 0.00001; 5 studies, 540 patients). Psychiatric symptoms, measured by Beck Depression Inventory, 2nd edition scores, showed greater improvement from baseline after GPi DBS than after STN DBS (standardized mean difference -2.28, 95% CI -3.73 to -0.84, p = 0.002; 3 studies, 382 patients). CONCLUSIONS GPi and STN DBS improve motor function and activities of daily living for PD patients. Differences in therapeutic efficacy for PD were not observed between the 2 procedures. STN DBS allowed greater reduction in medication for patients, whereas GPi DBS provided greater relief from psychiatric symptoms. An understanding of other symptomatic aspects of targeting each region and long-term observations on therapeutic effects are needed.

Associations of matrix metalloproteinase-9 and monocyte chemoattractant protein-1 concentrations with carotid atherosclerosis, based on measurements of plaque and intima–media thickness

PURPOSE To examine associations of matrix metalloproteinase-9 (MMP-9) and monocyte chemoattractant protein-1 (MCP-1) concentrations with the severity of carotid atherosclerosis, based on measurements of carotid plaque and intima-media thickness (IMT). METHODS This cross-sectional study included 116 stroke-free participants (45.7% males, 54.3% females; mean age, 64.73 ± 14.53 years). Serum MMP-9 and MCP-1 concentrations were measured, and plaque morphology, including total plaque score (PS), plaque stability, and IMT, was assessed ultrasonographically. Participants were grouped according to total PS (0, 1-2, ≥ 3), plaque stability (no plaque, stable, unstable) and IMT tertiles (<0.8 mm, 0.8-1 mm, >1 mm). Multinomial logistic regression models were used to assess the associations of MMP-9 and MCP-1 concentrations with plaque and IMT values after adjusting for vascular risk factors. RESULTS MMP-9 quartiles (vs. quartile 1) were significantly associated with a greater prevalence of plaque instability [Q2: odds ratio (OR) = 5.13, 95% confidence interval (CI) = 1.01-24.9, p = 0.042; Q3: OR = 15.5, 95% CI = 3.1-78.1, p = 0.001; Q4: OR = 13.2, 95% CI = 2.7-64.97, p = 0.001] and high total PS (Q3: OR = 10.02, 95% CI = 1.5-65.33, p = 0.016; Q4: OR = 21.5, 95% CI = 3.5-132.1, p = 0.001). MCP-1 concentration was significantly associated with IMT (OR = 22.94, 95% CI = 2.14-245.66, p = 0.01). CONCLUSIONS Elevated serum MMP-9 concentration was independently associated with high total carotid artery PS, plaque instability, and large IMT value. MCP-1 concentration was independently associated with IMT, but not with plaque morphology.

Resveratrol ameliorates oxidative stress and inhibits aquaporin 4 expression following rat cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion (I/R) is associated with increased levels of reactive oxygen species (ROS) and brain edema, which lead to the deterioration of patient prognosis. Resveratrol serves a neuroprotective role in I/R injury, and this role may be associated with its anti‑oxidative effects. However, resveratrols mechanism of action in cerebral I/R injury remains to be fully understood. In order to investigate the effect of resveratrol in cerebral I/R‑induced injury, male Sprague‑Dawley rats were randomly assigned to four groups: The sham‑operation group, the I/R group and the edaravone and resveratrol groups (I/R + E and I/R + R groups). Infarct volume was evaluated by 2,3,5‑tripenyltetrazolium chloride staining, brain edema was evaluated by the water content in the reperfused brain and malondialdehyde (MDA) was measured by the thiobarbituric acid method. Superoxide dismutase (SOD) levels were measured using the Total Superoxide Dismutase Assay kit. Inducible nitric oxide synthase (iNOS) levels in the hippocampus and cortex were measured by ELISA, and aquaporin 4 (AQP4) expression was measured by immunohistochemical staining and western blot analysis. The results demonstrated that resveratrol reduced the infarct volume and the incidence of brain edema and reduced neurological deficits. These outcomes were accompanied by reduced levels of MDA, iNOS and AQP4, and increased SOD levels in cerebral I/R injury. In conclusion, resveratrol protected against cerebral I/R injury by ameliorating oxidative stress and reducing AQP4 expression.

Alpha-2-macroglobulin and heparin cofactor II and the vulnerability of carotid atherosclerotic plaques: An iTRAQ-based analysis

Rupture of carotid atherosclerotic plaque may cause stroke, while few biomarker in clinic can evaluate carotid plaque vulnerability. In this study, we divided the recruited participants into no plaque, stable plaque, and vulnerable plaque group according to carotid ultrasonography, and screened the differentially expressed proteins in plasma of these participants using isobaric tags for relative and absolute quantitation labeling coupled with liquid chromatography-tandem mass spectrometry. 28 proteins were identified differentially expressed, among which alpha-2-macroglobulin (α2M) and heparin cofactor II (HCII) were found to be at hub position in the interactions of these proteins by STRING analysis and were selected for enzyme-linked immunosorbent assay measurement to assess their relevance with carotid plaques vulnerability and diagnostic efficiency. The plasma level of α2M was found positively correlated, while HCII level was negatively correlated with higher vulnerability of carotid plaques. Both proteins were efficient in differentiating stable and vulnerable carotid plaques. These findings provide potential new targets for the research of carotid plaque vulnerability. Plasma α2M and HCII may be potential biomarkers for evaluation of the vulnerability of carotid plaques if further studied.

New differentially expressed genes and differential DNA methylation underlying refractory epilepsy

Epigenetics underlying refractory epilepsy is poorly understood, especially in patients without distinctive genetic alterations. DNA methylation may affect gene expression in epilepsy without affecting DNA sequences. Herein, we analyzed genome-wide DNA methylation and gene expression in brain tissues of 10 patients with refractory epilepsy using methylated DNA immunoprecipitation linked with sequencing and mRNA Sequencing. Diverse distribution of differentially methylated genes was found in X chromosome, while differentially methylated genes appeared rarely in Y chromosome. 62 differentially expressed genes, such as MMP19, AZGP1, DES, and LGR6 were correlated with refractory epilepsy for the first time. Although general trends of differentially enriched gene ontology terms and Kyoto Encyclopedia of Genes and Genome pathways in this study are consistent with previous researches, differences also exist in many specific gene ontology terms and Kyoto Encyclopedia of Genes and Genome pathways. These findings provide a new genome-wide profiling of DNA methylation and gene expression in brain tissues of patients with refractory epilepsy, which may provide a basis for further study on the etiology and mechanisms of refractory epilepsy.

Inhibition of endothelin A receptor protects brain microvascular endothelial cells against hypoxia‑induced injury

Endothelin-1 (ET-1)-induced cell damage is commonly involved in ischemia/hypoxia-associated diseases. PD155080 [sodium 2-benzo (1.3)dioxol-5-yl-3-benzyl-4-(4‑metho-xyphenyl)-4-oxobut-2-enoate] is a selective endothelin A receptor (ETAR) antagonist that inhibits ET-1‑induced cell damage. The aim of this study was to investigate the effects of PD155080 on hypoxia-induced rat brain microvascular endothelial cell (BMEC) injury. BMECs were isolated from the cerebral cortex of Wistar rats and cultured in an anoxia chamber, containing 95% N(2) and 5% CO(2) for 12 h. BMEC injury was assessed by determining cellular ultra-microstructural changes and cell viability by MTT assay, trypan blue (TB) staining and measuring the lactate dehydrogenase (LDH) levels. ET-1 mRNA expression was detected by in situ hybridization and reverse transcription PCR (RT-PCR); the ET-1 protein level was measured by radioimmunoassay. Following exposure to hypoxic conditions, the viability of the BMECs was markedly decreased and the ultrastructure of the BMECs was damaged, as demonstrated by chromatin margination, chromatin agglutination, plasma edema, the increased number of intracellular liposomes and vacuoles, mitochondrial swelling and the expansion of a rough surfaced endoplasmic reticulum. The levels of ET-1 and ET-1 mRNA expression in the BMECs were increased following exposure to hypoxic conditions. Of note, the administration of PD155080 greatly enhanced the viability of the BMECs and ameliorated hypoxia-induced cellular injury. PD155080 also inhibited hypoxia-induced ET-1 production by the BMECs. In conclusion, PD155080 exerts protective effects against hypoxia-induced BMEC injury.

Resumption of antiplatelet therapy in patients with primary intracranial hemorrhage-benefits and risks: A meta-analysis of cohort studies

BACKGROUND Clinical disagreement over antiplatelet (AP) resumption in patients with primary intracranial hemorrhage (ICH) has long existed. This meta-analysis aimed to evaluate the benefits of AP resumption on preventing ischemic or thromboembolic events against its risks of promoting ICH recurrence or hematoma expansion. METHODS All relevant articles published in Pubmed, EMBASE, the Cochrane Library, and Science Direct from January 1950 to March 2017 were sourced, and the combined relative risk (RR) was calculated. RESULTS A total of 3648 articles were found, and after screening, 6 cohort studies including 1916 patients were included in this meta-analysis. AP resumption was associated with a decreased risk of ischemic or thromboembolic events (RR, 0.61; 95% confidence interval (CI), 0.48-0.79; P<0.01). There was no significant difference in the risk of ICH recurrence or hematoma expansion between patients with or without AP resumption (RR, 0.84; 95% CI, 0.47-1.51; P=0.56). CONCLUSION AP resumption in patients with primary ICH reduced the risk of ischemic or thromboembolic events, without significant increase of risk of ICH recurrence or hematoma expansion.

Overexpression of zinc-α2-glycoprotein suppressed seizures and seizure-related neuroflammation in pentylenetetrazol-kindled rats

BackgroundZinc-α2-glycoprotein (ZAG) is a 42-kDa protein reported as an anti-inflammatory adipocytokine. Evidences from clinical and experimental studies revealed that brain inflammation plays important roles in epileptogenesis and seizure. Interestingly, closely relationship between ZAG and many important inflammatory mediators has been proven. Our previous study identified ZAG in neurons and found that ZAG is decreased in epilepsy and interacts with TGFβ and ERK. This study aimed to investigate the role of ZAG in seizure and explore its effect on seizure-related neuroinflammation.MethodsWe overexpressed AZGP1 in the hippocampus of rats via adeno-associated virus vector injection and observed their seizure behavior and EEG after pentylenetetrazol (PTZ) kindling. The level of typical inflammation mediators including TNFα, IL-6, TGFβ, ERK, and ERK phosphorylation were determined.ResultsThe overexpression of AZGP1 reduced the seizure severity, prolonged the latency of kindling, and alleviated epileptiform discharges in EEG changes induced by PTZ. Overexpression of AZGP1 also suppressed the expression of TNFα, IL-6, TGFβ, and ERK phosphorylaton in PTZ-kindled rats.ConclusionsZAG may inhibit TGFβ-mediated ERK phosphorylation and inhibit neuroinflammation mediated by TNFα and IL-6, suggesting ZAG may suppress seizure via inhibiting neuroinflammation. ZAG may be a potential and novel therapeutic target for epilepsy.

Differentially expressed proteins underlying childhood cortical dysplasia with epilepsy identified by iTRAQ proteomic profiling

Cortical dysplasia accounts for at least 14% of epilepsy cases, and is mostly seen in children. However, the understanding of molecular mechanisms and pathogenesis underlying cortical dysplasia is limited. The aim of this cross-sectional study is to identify potential key molecules in the mechanisms of cortical dysplasia by screening the proteins expressed in brain tissues of childhood cortical dysplasia patients with epilepsy using isobaric tags for relative and absolute quantitation-based tandem mass spectrometry compared to controls, and several differentially expressed proteins that are not reported to be associated with cortical dysplasia previously were selected for validation using real-time polymerase chain reaction, immunoblotting and immunohistochemistry. 153 out of 3340 proteins were identified differentially expressed between childhood cortical dysplasia patients and controls. And FSCN1, CRMP1, NDRG1, DPYSL5, MAP4, and FABP3 were selected for validation and identified to be increased in childhood cortical dysplasia patients, while PRDX6 and PSAP were identified decreased. This is the first report on differentially expressed proteins in childhood cortical dysplasia. We identified differential expression of FSCN1, CRMP1, NDRG1, DPYSL5, MAP4, FABP3, PRDX6 and PSAP in childhood cortical dysplasia patients, these proteins are involved in various processes and have various function. These results may provide new directions or targets for the research of childhood cortical dysplasia, and may be helpful in revealing molecular mechanisms and pathogenesis and/or pathophysiology of childhood cortical dysplasia if further investigated.