Differential Expression of NME4 in Trophoblast Stem-Like Cells and Peripheral Blood Mononuclear Cells of Normal Pregnancy and Preeclampsia

Background@#Preeclampsia (PE) is known to arise from insufficient trophoblast invasion as uterine spiral arteries lack remodeling. A significant reduction in placental perfusion induces an ischemic placental microenvironment due to reduced oxygen delivery to the placenta and fetus, leading to oxidative stress. Mitochondria are involved in the regulation of cellular metabolism and the production of reactive oxygen species (ROS). NME/NM23 nuceloside diphosphate kinase 4 (NME4) gene is known to have the ability to supply nucleotide triphosphate and deoxynucleotide triphosphate for replication and transcription of mitochondria. Our study aimed to investigate changes in NME4 expression in PE using trophoblast stem-like cells (TSLCs) from induced pluripotent stem cells (iPSCs) as a model of early pregnancy and peripheral blood mononuclear cells (PBMNCs) as a model of late preterm pregnancy. @*Methods@#Transcriptome analysis using TSLCs was performed to identify the candidate gene associated with the possible pathophysiology of PE. Then, the expression of NME4 associated with mitochondrial function, p53 associated with cell death, and thioredoxin (TRX) linked to ROS were investigated through qRT-PCR, western blotting and deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling (TUNEL) assay. @*Results@#In patients with PE, NME4 was significantly downregulated in TSLCs but upregulated in PBMNCs. p53 was shown to be upregulated in TSLCs and PBMNCs of PE. In addition, western blot analysis confirmed that TRX expression had the tendency to increase in TSLCs of PE. Similarly, TUNEL analysis confirmed that the dead cells were higher in PE than in normal pregnancy. @*Conclusion@#Our study showed that the expression of the NME4 differed between models of early and late preterm pregnancy of PE, and suggests that this expression pattern may be a potential biomarker for early diagnosis of PE.

Cell Surface Antigen Display for Neuronal Differentiation-Specific Tracking

Cell therapeutic agents for treating degenerative brain diseases using neural stem cells are actively being developed. However, few systems have been developed to monitor in real time whether the transplanted neural stem cells are actually differentiated into neurons. Therefore, it is necessary to develop a technology capable of specifically monitoring neuronal differentiation in vivo. In this study, we established a system that expresses cell membrane-targeting red fluorescent protein under control of the Synapsin promoter in order to specifically monitor differentiation from neural stem cells into neurons. In order to overcome the weak expression level of the tissue-specific promoter system, the partial 5′ UTR sequence of Creb was added for efficient expression of the cell surface-specific antigen. This system was able to track functional neuronal differentiation of neural stem cells transplanted in vivo, which will help improve stem cell therapies.

Brain Plasticity and Neurorestoration by Environmental Enrichment

In the adult mammalian brain, neural-lineage cells are continuously generated in the subventricular zone (SVZ) and dentate gyrus of the hippocampus. These cells in vivo arising from the adult SVZ may be regulated by environmental enrichment (EE). EE is a method of raising animals in a huge cage containing novel objects, running wheels and social interaction with a complex combination of physical, cognitive, and social stimulations. EE can affect neural plasticity via overexpression of growth factors such as brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), fibroblast growth factor-2 (FGF-2), and synaptic activity-regulating genes. EE also have advanced effects on brain functions including the enhancement of motor and cognitive functions in normal and pathological states. Additionally, behavioral changes by EE are related with molecular changes including neurogenesis, gliogenesis, angiogenesis, axonal sprouting, and dendritic branching in the adult brain. In this review, we focus on brain plasticity and neurorestoration associated with molecular changes of neurotrophic growth factors such as BDNF, VEGF, IGF-1, FGF-2 and synaptic activity-regulating genes that occurs in interaction to EE.