NCAM mimetic peptide P2 synergizes with bone marrow mesenchymal stem cells in promoting functional recovery after stroke.

The neural cell adhesion molecule (NCAM) promotes neural development and regeneration. Whether NCAM mimetic peptides could synergize with bone marrow mesenchymal stem cells (BMSCs) in stroke treatment deserves investigation. We found that the NCAM mimetic peptide P2 promoted BMSC proliferation, migration, and neurotrophic factor expression, protected neurons from oxygen-glucose deprivation through ERK and PI3K/AKT activation and anti-apoptotic mechanisms in vitro. Following middle cerebral artery occlusion (MCAO) in rats, P2 alone or in combination with BMSCs inhibited neuronal apoptosis and induced the phosphorylation of ERK and AKT. P2 combined with BMSCs enhanced neurotrophic factor expression and BMSC proliferation in the ischemic boundary zone. Moreover, combined P2 and BMSC therapy induced translocation of nuclear factor erythroid 2-related factor, upregulated heme oxygenase-1 expression, reduced infarct volume, and increased functional recovery as compared to monotreatments. Treatment with LY294002 (PI3K inhibitor) and PD98059 (ERK inhibitor) decreased the neuroprotective effects of combined P2 and BMSC therapy in MCAO rats. Collectively, P2 is neuroprotective while P2 and BMSCs work synergistically to improve functional outcomes after ischemic stroke, which may be attributed to mechanisms involving enhanced BMSC proliferation and neurotrophic factor release, anti-apoptosis, and PI3K/AKT and ERK pathways activation.

Dialysis adequacy and hemoglobin levels predict cerebral atrophy in maintenance-hemodialysis patients.

The pathogenesis of cerebral atrophy (CA) is not clear. Previous studies show a high incidence of preterm CA in hemodialysis patients. This study aims to investigate the factors influencing CA and to derive a CA prediction nomogram in maintenance-hemodialysis patients. First, brain volumes of hemodialysis patients (≤55 years) were compared against age- and sex-matched healthy controls, and differences were revealed in bilateral insular cisterns width, maximum cerebral sulci width, Evans index, ventricular-brain ratio, frontal atrophy index, and temporal lobe ratio. Then, the patients were divided equally into "no or mild" or "severe" CA groups. Potential factors influencing CA were screened. Kt/V (urea removal index) and hemoglobin levels negatively correlated with CA degree, and were used to establish a nomogram within randomly assigned training and validation patient groups. The areas under the receiver operating characteristic curves (AUROC) for training and validation groups were 0.703 and 0.744, respectively. When potassium and calcium were added to the nomogram, the AUROC for training/validation group increased to 0.748/0.806. The nomogram had optimal AUROC for training (0.759) and validation (0.804) groups when albumin was also included. Hemodialysis patients showed reduced anterior brain volumes and the nomogram established herein may have predictive value for developing CA.

Bone Marrow Mesenchymal Stem Cells Exert Protective Effects After Ischemic Stroke Through Upregulation of Glutathione.

Bone marrow mesenchymal stem cells (BMSCs) have been shown to promote stroke recovery, however, the underlying mechanisms are not well understood. In this study naïve rats were intravenously injected with syngeneic BMSCs to screen for potential differences in brain metabolite spectrum versus vehicle-treated controls by capillary electrophoresis-mass spectrometry. A total of 65 metabolites were significantly changed after BMSC treatment. Among them, 5-oxoproline, an intermediate in the biosynthesis of the endogenous glutathione (GSH), was increased. To confirm the obtained results and investigate the metabolic pathways, BMSCs were injected into rats 24 h after middle cerebral artery occlusion (MCAO). Rats receiving vehicle solution and sham-operated animals served as controls. High performance liquid chromatography, reverse transcription-quantitative polymerase chain reaction, and Western blotting revealed that intravenous BMSC application increased the levels of 5-oxoproline and GSH in MCAO rats, as well as the expression of key enzymes involved in GSH synthesis including, gamma-glutamylcyclotransferase and gamma-glutamylcysteine ligase. Subsequent clinical investigation confirmed that acute ischemic stroke patients had higher plasma 5-oxoproline and GSH levels than age- and sex-matched non-stroke controls. The optimal cutoff value for 5-oxoproline diagnosing acute ischemic stroke (≤ 7d) was 3.127 µg/mL (sensitivity, 63.4 %; specificity, 81.2 %) determined by receiver characteristic operator curve. The area under the curve was 0.782 (95 % confidence interval: 0.718-0.845). Our findings indicate that BMSCs play a protective role in ischemic stroke through upregulation of GSH and 5-oxoproline is a potential biomarker for acute ischemic stroke. Ischemic stroke causes oxidative stress and induction of endogenous, glutathione-dependent anti-oxidative mechanisms. 5-oxoproline, an important metabolite in glutathione biosynthesis, could serve as a biomarker of acute ischemic stroke. Moreover, intravenous bone marrow mesenchymal stem cell (BMSC) treatment after experimental stroke upregulates the expression of key enzymes involved in glutathione synthesis, which results in better antioxidative defense and improved stroke outcome.

NCAM regulates temporal specification of neural progenitor cells via profilin2 during corticogenesis.

The development of cerebral cortex requires spatially and temporally orchestrated proliferation, migration, and differentiation of neural progenitor cells (NPCs). The molecular mechanisms underlying cortical development are, however, not fully understood. The neural cell adhesion molecule (NCAM) has been suggested to play a role in corticogenesis. Here we show that NCAM is dynamically expressed in the developing cortex. NCAM expression in NPCs is highest in the neurogenic period and declines during the gliogenic period. In mice bearing an NPC-specific NCAM deletion, proliferation of NPCs is reduced, and production of cortical neurons is delayed, while formation of cortical glia is advanced. Mechanistically, NCAM enhances actin polymerization in NPCs by interacting with actin-associated protein profilin2. NCAM-dependent regulation of NPCs is blocked by mutations in the profilin2 binding site. Thus, NCAM plays an essential role in NPC proliferation and fate decision during cortical development by regulating profilin2-dependent actin polymerization.

Induction of immunological tolerance to myelinogenic glial-restricted progenitor allografts.

The immunological barrier currently precludes the clinical utilization of allogeneic stem cells. Although glial-restricted progenitors have become attractive candidates to treat a wide variety of neurological diseases, their survival in immunocompetent recipients is limited. In this study, we adopted a short-term, systemically applicable co-stimulation blockade-based strategy using CTLA4-Ig and anti-CD154 antibodies to modulate T-cell activation in the context of allogeneic glial-restricted progenitor transplantation. We found that co-stimulation blockade successfully prevented rejection of allogeneic glial-restricted progenitors from immunocompetent mouse brains. The long-term engrafted glial-restricted progenitors myelinated dysmyelinated adult mouse brains within one month. Furthermore, we identified a set of plasma miRNAs whose levels specifically correlated to the dynamic changes of immunoreactivity and as such could serve as biomarkers for graft rejection or tolerance. We put forward a successful strategy to induce alloantigen-specific hyporesponsiveness towards stem cells in the CNS, which will foster effective therapeutic application of allogeneic stem cells.

Long-Term Survival of Primary Intracranial Plasmablastic Lymphoma: Case Report and Review of the Literature.

BACKGROUND: Primary intracranial plasmablastic lymphoma (PIPBL) is a rare malignant tumor. CASE DESCRIPTION: We present a case of PIPBL in a 32-year-old man who complained of a progressive growing, painful mass on the right parieto-occipital part of head. Computed tomography and magnetic resonance imaging revealed a homogeneously enhanced mass with partial bone destruction. The patient underwent total resection and cranioplasty in one stage. Histopathologic examination showed large tumor cells with immunoblast-like nuclei. Immunohistochemical staining displayed CD38(+), CD138(+), Mum-1(+), CD20(-), and PAX-5(-). The patient received chemotherapy. The patient has survived more than 3.5 years after operation, with follow-up. We also review the clinical data, molecular pathologic traits, treatment, and prognosis of additional 6 cases with PIPBL in the literature. CONCLUSIONS: This study provides important clinical information for the diagnosis and treatment of PIPBL.

Infarction of the corpus callosum: a retrospective clinical investigation.

OBJECTIVES: The aim of this study was to investigate patients with ischemic infarctions in the territory of the corpus callosum to advance our understanding of this rare stroke subtype by providing comprehensive descriptive and epidemiological data. METHODS: From January 1, 2010 to June 30, 2014, all cases of acute ischemic stroke diagnosed by clinical manifestation and diffusion weighted imaging in Dalian Municipal Central Hospital were investigated. The patients presenting with corpus callosum infarctions were selected and further allocated into genu and/or body and splenium infarction groups. Proportion, lesion patterns, clinical features, risk factors and etiology of corpus callosum infarction were analyzed. RESULTS: Out of 1,629 cases, 59 patients (3.6%) with corpus callosum infarctions were identified by diffusion weighted imaging, including 7 patients who had ischemic lesions restricted to the corpus callosum territory. Thirty six patients had lesions in the splenium (61.0%). Corpus callosum infarction patients suffered from a broad spectrum of symptoms including weakness and/or numbness of the limbs, clumsy speech, and vertigo, which could not be explained by lesions in corpus callosum. A classical callosal disconnection syndrome was found in 2 out of all patients with corpus callosum infarctions. Statistical differences in the risk factor and infarct pattern between the genu and/or body group and splenium group were revealed. CONCLUSION: Corpus callosum infarction and the callosal disconnection syndrome were generally rare. The most susceptible location of ischemic corpus callosum lesion was the splenium. Splenium infarctions were often associated with bilateral cerebral hemisphere involvement (46.2%). The genu and/or body infarctions were associated with atherosclerosis. The most common cause of corpus callosum infarction probably was embolism.

Shenfu injection protects human ECV304 cells from hydrogen peroxide via its anti-apoptosis way.

ETHNOPHARMACOLOGICAL RELEVANCE: The pathogenesis of thromboangiitis obliterans (TAO) has not been fully elucidated until now. Shenfu injection (SFI), a traditional Chinese formula has been widely used clinically for the treatment of cardiovascular diseases for more than two decade. Our previous results first suggested that SFI can cause a significant therapeutic effect on experimental TAO model rats. This experiment was designed to further investigate the protective effect of SFI on VEC damaged by hydrogen peroxide (H2O2) oxidative stress in vitro. METERIALS AND METHODS: The cell viability was evaluated by the MTT assay, the activities of SOD and GSH-PX and the content of MDA in the supernatants of the cultured ECV304 cells were evaluated by a colorimetry method, cell apoptosis was detected by flow cytometry and an AO/EB double staining method. The protein expressions of Bcl2, Bax and caspase-3 were examined by Western blotting. RESULTS: When compared with control group, lower survival rate of ECV304 cells was observed in H2O2 group (p<0.01) ; 20µl/ml, 30µl/ml and 40µl/ml SFI increased the survival rate of ECV304 cells under H2O2 oxidative stress (p<0.05 and p<0.01). The activities of SOD and GSH-PX were higher and MDA level was lower in H2O2 group than those in control group. These effects of H2O2 on SOD, GSH-PX activities and MDA content were reversed by SFI in concentration-dependent way (p<0.05 and p<0.01). Flow cytometry and AO-EB double staining discovered that SFI pretreatment inhibited the ECV304 cells apoptosis. The protein expression of caspase3 in 30µl/ml and 40µl/ml SFI groups significantly decreased whereas Bcl2 protein expressions in 20µl/ml, 30µl/ml and 40µl/ml SFI groups were higher than H2O2 group, with Bax protein expression much lower than H2O2 group (p<0.05 and p<0.01). CONCLUSIONS: Our findings suggest that SFI could prevent the ECV304 cells against H2O2 oxidative-stress by enhancing antioxidant enzyme activities, reducing the membrane lipid peroxidation, as well as upregulating antiapoptotic and downregulating apoptosis protein expressions.

Pregnancy-associated plasma protein A up-regulated by progesterone promotes adhesion and proliferation of trophoblastic cells.

Embryo implantation and development is a complex biological process for the establishment of the successful pregnancy. Progesterone is a critical factor in the regulation of embryo adhesion to uterine endometrium and proliferation. Although it has been reported that pregnancy-associated plasma protein A (PAPPA) is increased in pregnant women, the relationship between progesterone and PAPPA, and the effects of PAPPA on embryo adhesion and proliferation are still not clear. The present results showed that the serum level of progesterone and PAPPA was closely correlated by ELISA assay (p<0.01). PAPPA was detected in the villi of early embryo by RT-PCR, Western blot, immunohistochemistry and immunofluorescent staining. Moreover, PAPPA was significantly up-regulated by progesterone in trophoblastic (JAR) cells by Real-time PCR and ELISA assay (p<0.01); while the expression was decreased by the progesterone receptor inhibitor RU486. The down-regulation of PAPPA by siRNA transfection or up-regulation of PAPPA by progesterone treatment significantly decreased or increased the adhesion rate of trophoblastic cells to human uterine epithelial cell lines (RL95-2 and HEC-1A), respectively (p<0.01), as well as the proliferation of trophoblastic cells. In conclusion, PAPPA is up-regulated by progesterone, which promotes the adhesion and proliferation potential of trophoblastic cells.