Endothelial Cdk5 deficit leads to the development of spontaneous epilepsy through CXCL1/CXCR2-mediated reactive astrogliosis.

Blood-brain barrier (BBB) dysfunction has been suggested to play an important role in epilepsy. However, the mechanism mediating the transition from cerebrovascular damage to epilepsy remains unknown. Here, we report that endothelial cyclin-dependent kinase 5 (CDK5) is a central regulator of neuronal excitability. Endothelial-specific Cdk5 knockout led to spontaneous seizures in mice. Knockout mice showed increased endothelial chemokine (C-X-C motif) ligand 1 (Cxcl1) expression, decreased astrocytic glutamate reuptake through the glutamate transporter 1 (GLT1), and increased glutamate synaptic function. Ceftriaxone restored astrocytic GLT1 function and inhibited seizures in endothelial Cdk5-deficient mice, and these effects were also reversed after silencing Cxcl1 in endothelial cells and its receptor chemokine (C-X-C motif) receptor 2 (Cxcr2) in astrocytes, respectively, in the CA1 by AAV transfection. These results reveal a previously unknown link between cerebrovascular factors and epileptogenesis and provide a rationale for targeting endothelial signaling as a potential treatment for epilepsy.

GPR124 facilitates pericyte polarization and migration by regulating the formation of filopodia during ischemic injury.

Prolonged occlusion of multiple microvessels causes microvascular injury. G protein-coupled receptor 124 (GPR124) has been reported to be required for maintaining central nervous system (CNS) angiogenesis and blood-brain barrier integrity. However, the molecular mechanisms by which GPR124 regulates pericytes during ischemia have remained elusive. Methods: A microsphere embolism-induced ischemia model was used to evaluate the expression of GPR124 following microsphere embolism. Immunocytochemistry and stochastic optical reconstruction microscopy imaging were used to assess the expression and distribution of GPR124 in human brain vascular pericytes (HBVPs) and after the treatment with 3-morpholino-sydnonimine (SIN-1) or oxygen-glucose deprivation (OGD). The effect of GPR124 knockdown or overexpression on HBVP migration was analyzed in vitro using wound healing assays and a microfluidic device. GPR124 loss-of-function studies were performed in HBVPs and HEK293 cells using CRISPR-Cas9-mediated gene deletion. Time-lapse imaging was used to assess dynamic changes in the formation of filopodia in an individual cell. Finally, to explore the functional domains required for GPR124 activity, deletion mutants were constructed for each of the N-terminal domains. Results: GPR124 expression was increased in pericytes following microsphere embolism. Morphological analysis showed localization of GPR124 to focal adhesions where GPR124 bound directly to the actin binding protein vinculin and upregulated Cdc42. SIN-1 or OGD treatment redistributed GPR124 to the leading edges of HBVPs where GPR124 signaling was required for pericyte filopodia formation and directional migration. Partial deletion of GPR124 domains decreased SIN-1-induced filopodia formation and cell migration. Conclusion: Taken together, our results provide the first evidence for a role of GPR124 in pericyte migration under ischemic conditions and suggest that GPR124 was essential for Cdc42 activation and filopodia formation.

A fluorescent peptidyl substrate for visualizing peptidyl-prolyl cis/trans isomerase activity in live cells.

This communication reports on a fluorescent probe (PPI-P) for imaging active peptidyl-prolyl cis/trans isomerases in live cells. PPI-P is capable of responding to both recombinant and cellular PPIases fluorogenically, and has been shown to specifically image active PPIases in live cells.

Functional Genomic Analyses Identify Pathways Dysregulated in Animal Model of Autism.

BACKGROUND: Autism spectrum disorders (ASDs) are a heterogeneous group of neurodevelopmental disorders that display complicated behavioral symptoms. METHODS: Using gene expressing profiling and the weighted gene co-expression network analysis (WGCNA), we studied genes coregulated by similar factors such as genetic variants or environmental effects in the hippocampus in an animal model of autism. RESULTS: From microarray data, we identified 21,388 robustly expressed genes of which 721 genes were found to be differently expressed in the valproic acid-treated group compared to the control group. WGCNA identified multiple co-expression modules known to associate with cognitive function, inflammation, synaptic, and positive regulation of protein kinase activating. Many of these modules, however, have not been previously linked to autism spectrum disorders which included G-protein signaling, immunity, and neuroactive ligand-receptor interaction pathway. The downregulation of the highly connected (hub) genes Taar7h and Taar7b in neuroactive ligand-receptor interaction pathway was validated by qRT-PCR. Immunoblotting and immunohistochemistry further showed that TAAR7 expression was downregulated not only in valproic acid-treated animals, but also BTBR T+tf/J mice. CONCLUSIONS: This study highlights the advantages of gene microarrays to uncover co-expression modules associated with autism and suggests that Taars and related gene regulation networks may play a significant role in autism.

A prospective, randomized, multi-center trial to investigate Actovegin in prevention and treatment of acute oral mucositis caused by chemoradiotherapy for nasopharyngeal carcinoma.

PURPOSE: A multi-center prospective randomized trial was conducted to evaluate the efficacy and safety of Actovegin in the prevention and treatment of chemoradiotherapy-induced acute oral mucositis. METHODS AND MATERIALS: Between February 2006 and May 2007, 156 evaluable patients with nasopharyngeal carcinoma were randomized to Group 1 (n=53) for prevention, Group 2 (n=51) for treatment, and Group 3 (n=52) for control. All patients received concomitant chemoradiotherapy ± induction chemotherapy. Radiation technique and dose were similar among 3 groups. Intravenous Actovegin of 30 ml daily (5 days/week) was administrated from day 1 of the radiotherapy for Group 1 and from the onset of grade 2 mucositis for Group 2, until the end of the radiotherapy. RESULTS: The incidence of grade 3 mucositis was lower in Group 1 compared with Group 3 (26.4% vs. 55.8%, P=0.002). Group 2 had a lower progression rate of mucositis from grade 2 to 3 compared with Group 3 (39.2% vs. 60.4%, P=0.035). There was no difference in the onset time of grade 3 mucositis among 3 groups. Actovegin was well tolerated and no treatment-related adverse events were observed. CONCLUSIONS: Actovegin is effective in the prevention and treatment of chemoradiotherapy-induced oral mucositis.

[Phase II clinical trial of h-R3 combined radiotherapy for locoregionally advanced nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE: Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies are easily to produce human anti-murine antibody response at present clinical use. This may influence therapeutic effect. This study was to evaluate the short-term and long-term efficacy and toxicity of the humanized anti-EGFR monoclonal antibody h-R3 in combination with radiotherapy for locoregionally advanced nasopharyngeal carcinoma (NPC). METHODS: Patients with newly diagnosed stage III-IVb (UICC 1997) NPC, who had moderate or strong EGFR expression, were randomized into radiotherapy alone group or radiotherapy combined h-R3 group. Similar dosage and technique of radiotherapy was administered in both groups. The combination group received weekly intravenous infusion of 100 mg h-R3 during radiotherapy. The short-term efficacy was evaluated according to WHO criteria. The survival was analyzed by Kaplan-Meier method. RESULTS: A total of 35 patients were enrolled, 17 in radiotherapy alone group and 18 in combination group. During treatment, only 1 patient withdrew from the combination group. The overall complete remission (CR) rates at the end of treatment, 5 and 17 weeks after treatment were significantly higher in combination group than in radiotherapy alone group (72.2% vs. 35.3%, 83.3% vs. 41.2%, and 83.3% vs. 47.1%, P<0.05). Median follow-up time was 31.9 months (range, 4.2-40.7 months). No significant differences in 3-year locoregional control, distant metastasis-free survival and overall survival rates between the 2 groups were found. Except for 1 patient suffered from grade 2 vomiting, no patient developed other adverse events in combination group. No significant differences in radiotherapy-related adverse events between the 2 groups were observed. CONCLUSIONS: h-R3 is a safe drug which may enhance the response of advanced NPC patients to radiotherapy. However, h-R3 seems not to significantly affect the long-term outcomes.