Effect of stromal cell-derived factor-1/CXCR4 axis in neural stem cell transplantation for Parkinson's disease.

Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson's disease, but its specific mechanism of action is still unclear. Stromal cell-derived factor-1 and its receptor, chemokine receptor 4 (CXCR4), are important regulators of cell migration. We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson's disease. A Parkinson's disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway, and then treated with 5 µL of neural stem cell suspension (1.5 × 104/L) in the right substantia nigra. Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation. Parkinson-like behavior in rats was detected using apomorphine-induced rotation. Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase, CXCR4, and stromal cell-derived factor-1 in the brain. Using quantitative real-time polymerase chain reaction, the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured. In addition, western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4. Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation, increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra, and enhanced the immunoreactivity of tyrosine hydroxylase, CXCR4, and stromal cell-derived factor-1 in the brain. Injection of AMD3100 inhibited the aforementioned effects. These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson's disease. This study was approved by the Animal Care and Use Committee of Kunming Medical University, China (approval No. SYXKK2015-0002) on April 1, 2014.

Transplantation of Nurr1-overexpressing neural stem cells and microglia for treating parkinsonian rats.

BACKGROUND: Neural stem cells (NSCs) transplantation is considered a promising treatment for Parkinson's disease. But most NSCs are differentiated into glial cells rather than neurons, and only a few of them survive after transplantation due to the inflammatory environment. METHODS: In this study, neural stem cells (NSCs) and microglial cells both forced with the Nurr1 gene were transplanted into the striatum of the rat model of PD. The results were evaluated through reverse transcription polymerase chain reaction (RT-PCR), Western blot, and immunofluorescence analysis. RESULTS: The behavioral abnormalities of PD rats were improved by combined transplantation of NSCs and microglia, both forced with Nurr1. The number of tyrosine hydroxylase+ cells in the striatum of PD rats increased, and the number of Iba1+ cells decreased compared with the other groups. Moreover, the dopamine neurons differentiated from grafted NSCs could still be detected in the striatum of PD rats after 5 months. CONCLUSIONS: The results suggested that transplantation of Nurr1-overexpressing NSCs and microglia could improve the inhospitable host brain environments, which will be  a new potential strategy for the cell replacement therapy in PD.

Inhibition of tumor growth and angiogenesis by 2-(4-aminophenyl) benzothiazole in orthotopicglioma C6 rat model.

In the present study antitumor effect of 2-(4-aminophenyl) benzothiazole (BTZ) was evaluated against human U251 and rat C6 glioma cell lines using MTT assay. It was observed that BTZ exhibited significant antitumor effect with IC50 of 3.5 and 4 µM against human U251 and rat C6 glioma cells respectively. To gain in-depth insights about the antitumor effect of BTZ, glioma xenograft rat model was prepared. The rats were treated with 10 mg and 15 mg/kg body weight doses of BTZ daily for 21 days after C6 cell administration. Treatment of the rats with BTZ reduced the tumor volume to 12% compared to 100% in the untreated rats. TUNEL assay showed a remarkable increase in the proportion of apoptotic cells in the BTZ treated rats than those in the untreated rats. The increase in the population of apoptotic cells was 23-fold compared to control. Immuno-histological staining revealed marked reduction (16%) in the proportion of CD31-stained vessels in the BTZ treated rats than those of the untreated rats. These changes were accompanied with decreased transcript levels of vascular endothelial growth factor (VEGF) and the VEGF receptor Flt1 as well as ERK1/2 and matrix metalloproteinase-2 (MMP2). Moreover, BTZ altered the expression of several cell cycle control proteins. While as pRb protein expression decreased, E2F1 remained unaltered and cyclin D1 protein and p53 expression was enhanced. Taken together, the results indicate that BTZ is a potent inhibitor of glioma cell proliferation in vivo and exerts its effects on cell cycle control and angiogenesis related proteins.

Nurr1 promotes neurogenesis of dopaminergic neuron and represses inflammatory factors in the transwell coculture system of neural stem cells and microglia.

INTRODUCTION: Neural stem cells (NSCs) are the most promising cells for cell replacement therapy for Parkinson's disease (PD). However, a majority of the transplanted NSCs differentiated into glial cells, thereby limiting the clinical application. Previous studies indicated that chronic neuroinflammation plays a vital role in the degeneration of midbrain DA (mDA) neurons, which suggested the developing potential of therapies for PD by targeting the inflammatory processes. Thus, Nurr1 (nuclear receptor-related factor 1), a transcription factor, has been referred to play a pivotal role in both the differentiation of dopaminergic neurons in embryonic stages and the maintenance of the dopaminergic phenotype throughout life. AIM: This study investigated the effect of Nurr1 on neuroinflammation and differentiation of NSCs cocultured with primary microglia in the transwell coculture system. RESULTS: The results showed that Nurr1 exerted anti-inflammatory effects and promoted the differentiation of NSCs into dopaminergic neurons. CONCLUSIONS: The results suggested that Nurr1 protects dopaminergic neurons from neuroinflammation insults by limiting the production of neurotoxic mediators by microglia and maintain the survival of transplanted NSCs. These phenomena provided a new theoretical and experimental foundation for the transplantation of Nurr1-overexpressed NSCs as a potential treatment of PD.

Long non-coding RNA PAR5 inhibits the proliferation and progression of glioma through interaction with EZH2.

Emerging evidence suggests that long non-coding RNAs (lncRNAs) may be involved in modulating various aspects of tumor biology and serve as potential therapeutic targets as well as novel biomarkers in the treatment of glioma. The present study investigated the role of lncRNA, Prader Willi/Angelman region RNA 5 (PAR5; also known as PWAR5), in glioma and its clinical significance in glioma cases. The expression levels of PAR5 were determined in clinical samples and U87, U251 cells using real-time reverse transcription quantitative polymerase chain reaction (qRT-PCR) analysis. The effects of PAR5 on cell proliferation, migration and invasion were determined using in vitro assays. RNA immunoprecipitation (RIP) and RNA pull-down assays, as well as the evauation of the expression of various oncogenes were carried out to reveal the underlying mechanisms. We found that PAR5 was significantly downregulated in glioma tissues and cell lines. Furthermore, PAR5 expression was negatively correlated with tumor size, World Health Organization (WHO) grade and Karnofsky performance score (KPS). Patients with low PAR5 expression in tumors had a worse overall survival compared to those with higher expression. Finally, in vitro restoration of PAR5 expression inhibited human glioma cell proliferation, invasion and migration by binding to EZH2 and regulating oncogene expression. This finding may provide a therapeutic approach for the future treatment of glioma.

MicroRNA-584 functions as a tumor suppressor and targets PTTG1IP in glioma.

MicroRNAs (miRNAs) are small noncoding RNA molecules that regulate gene expression at the post transcriptional level. Compelling evidence shows that there are causative links between miRNAs deregulation and cancer development and progression. In this study, we demonstrated that miR-584 was downregulated in human glioma and could suppress growth of the human glioma cell line U87-MG and U251-MG. Bioinformatics analysis indicated that PTTG1IP was a putative target of miR-584. In a Luciferase reporter system, we confirmed that PTTG1IP was a direct target gene of miR-584. These findings indicate that miR-584 suppresses glioma cell growth by negatively regulating the expression of PTTG1IP, suggesting that miR-584 has a tumor suppressive role in human glioma pathogenesis.