Cell and Tissue Journal

Abstract Aim: The purpose of this study is to examine DJ-1effect on increasing survival of dopaminergic (DAergic) cells against parkinsonian toxicity.
Material and Methods: First recombinant lenti-viruses transporters were produced with both DJ-1 and reporter Jred genes and were used to cells infection. To this end, three lentiviruses vectors namely transporter, packaging and envelope were applied for co-transfection of HEK-293T cells as virus-producing cell line. 24 and 48 hours transfected cell media were collected and concentrated till lentivirus stock generation. Following transduction of DAergic PC12 cells with this concentrated virus stock, the infected cells overexpressed DJ-1. After treatment of these transduced cells with the 6-OHDA toxin, their survival rate was measured in comparison with control.
Results: Transfection HEK-293T cells steps and PC12 cells transduction with the virus stock were done successful, because reporter Jred gene expression was observed using fluorescence microscope in both steps. Then DJ-1 overexpression was proofed using RT-PCR method. Next experiments indicated that DJ-1 overexpression causes significant increase in PC12 cells survival against produced toxicity of 6-OHDA. PC12 cell survival percentage that had DJ-1-overexpressing was 30% more than control cells survival percentage and this increasing was statistically significant.
Conclusion: increasing of DJ-1 expression in DAergic PC12 cells significantly increased their resistance and perpetuity against 6-OHDA neurotoxicity.

Abstract Aim: The aim of this study was to generate recombinant lentiviruses carrying Nurr1 to express it in human cells. Material and methods: The IRES-EGFP fragment was isolated from the pIRES2-EGFP vector using restriction enzymes BglII/NotI and made blunt-ended using Klenow. The transfer vector PNL-EGFP/CMV/WPREdU3 was digested with NheI/XhoI and made blunt-ended. Finally, the isolated IRES-EGFP fragment was inserted into this lentivirus vector to generate lentivirus construct (I). The human Nurr1 gene was then isolated from the PCMX-NOT vector using BamHI and XhoI and inserted into construct (I) pre-digested with BamHI and SalI. At this step lentivirus construct (II) as our final transfer construct was generated. In order to generate recombinant lentiviruses, we then transfected the HEK-293T cell line with transfer vector plus packaging and envelope vectors. Cell medium full of virus particles was collected and passed through Amicon filters to produce a concentrated virus stock. The stock was ultimately used for transduction of fresh HEK-293T cells. EGFP expression was shown under fluorescent microscope and Nurr1 expression was analyzed using RT-PCR. Results: Enzymatic tests confirmed the correct cloning of the hNurr1gene into the lentivirus backbone. Observation by fluorescent microscopy showed EGFP expression post-transfection and post-transduction. RT-PCR demonstrated Nurr1 expression at both stages. Conclusion: In this study, lentiviruses carrying the human Nurr1 gene were produced and used for transduction of human cell line HEK-293T. The transduced cells successfully expressed the Nurr1 gene.

Abstract Aim: The aim of the current study was to isolate microglial cells from neonatal rat brain, activate the cells using lipopolysaccharide (LPS) and examine the effect of the inflammatory factors that they express on dopaminergic (DAergic) neurons.
Materials and Methods: mixed glial cells were isolated from 1-3 day rat neonatal brains and then microglial cells were extracted from them. Upon treatment of the cells with LPS, their conditioned media (CM) were collected. DAergic SH-SY5Y cell line was seeded in 96-well plates and fed with the collected CM. The rate of viability and apoptosis of the neuronal cells was examined using MTT and apoptosis tests and the data were analyzed statistically.
Results: Ten to thirteen days after isolation, mixed glial cells were composed of three types: astroglia, oligodendrocytes and microglia. Microglia were floating while semi-attached to the surface. Twenty four hours post-isolation, these cells were transferred to and cultured in separate dishes where they formed spindled and ramified phenotypes. At this stage, the cells were treated with LPS to be activated. This activation was demonstrated by morphological changes from spindle-like form to amoeboid form, detection of increase in NO expression using Griess test and induction of inflammatory iNOS and TNF-α gene expression. Also teatment of SH-SY5Y cell line with conditioned medium of activated microglia led to both apoptotic and necrotic cell death.
Conclusion: LPS-mediated activation of microglia results in overexpression of neuroinflammatory markers. The overproduction of these markers results in both apoptotic and necrotic cell death amongst DAergic neurons via neuroinflammation.