• Animal cells and systems
• /
• v.12 no.4
• /
• pp.203-209
• /
• 2008

Berberine, an isoquinoline alkaloid found in Coptidis Rhizoma(goldenthread) extract, has multiple pharmacological effects such as anti-inflammatory, antimicrobial and anti-ischemic effects. In the present study, we examined the effects of berberine on neuronal survival and differentiation in a hippocampal precursor cell line and in the memory deficient rat model. Berberine increased in a dose dependent manner the survival of hippocampal precursor cells as well as differentiated cells. In addition, berberine promoted neuronal differentiation of hippocampal precursor cells. In the memory deficient rat model induced by stereotaxic injection of ibotenic acid into entorhinal cortex(Ibo model), hippocampal cells were increased about 2.7 fold in the pyramidal layer of CA1 region and about 2 fold in the dentate gyrus by administration of berberine after 2 weeks of ibotenic acid injection. Furthermore, neuronal cells immunoreactive to calbindin were increased in the hippocampus and entorhinal cortex area by administration of berberine. Taken together, these results suggest that berberine has neuroprotective effect in the Ibo model rat brain by promoting the neuronal survival and differentiation.

• BMB Reports
• /
• v.46 no.11
• /
• pp.527-532
• /
• 2013

Gangliosides are complex glycosphingolipids that are the major component of cytoplasmic cell membranes, and play a role in the control of biological processes. Human mesenchymal stem cells (hMSCs) have received considerable attention as alternative sources of adult stem cells because of their potential to differentiate into multiple cell lineages. In this study, we focus on various functional roles of gangliosides in the differentiation of hMSCs into osteoblasts or neuronal cells. A relationship between gangliosides and epidermal growth factor receptor (EGFR) activation during osteoblastic differentiation of hMSCs was observed, and the gangliosides may play a major role in the regulation of the differentiation. The roles of gangliosides in osteoblast differentiation are dependent on the origin of hMSCs. The reduction of ganglioside biosynthesis inhibited the neuronal differentiation of hMSCs during an early stage of the differentiation process, and the ganglioside expression can be used as a marker for the identification of neuronal differentiation from hMSCs.

• Development and Reproduction
• /
• v.15 no.2
• /
• pp.173-178
• /
• 2011

The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA) is a potent monoaminergic neurotoxin with the potential to cause serotonergic neurotoxicity, but has become a popular recreational drug. Little has been known about the cellular effects induced by MDMA. This report shows that MDMA inhibits neuronal cell growth and differentiation. MDMA suppressed neuronal cell growth. The results of quantitative real-time PCR analysis showed that Egr-1 expression is elevated in mouse embryo and neuroblastoma cells after MDMA treatment. Transiently transfected Egr-1 interfered with the neuronal differentiation of neuroblastoma cells such as SH-SY5Y and PC12 cells. These findings provide evidence that the abuse of MDMA during pregnancy may impair neuronal development via an induction of Egr-1 over-expression.

• Journal of Life Science
• /
• v.26 no.12
• /
• pp.1355-1359
• /
• 2016

Human bone marrow mesenchymal stem cells (hBM-MSCs) can differentiate into various cell types including osteoblasts, adipocytes, chondrocytes, and myocytes. Previous studies, including our own, have shown that MSCs can also differentiate into neuron-like cells. However, their rate of neuronal differentiation is not sufficient for application to stem cell therapy, which requires well-defined cell types. For this purpose, we first examined the expression of neuronal lineage markers (GFAP, MAP-2, KCNH1, Nestin, NF-M, and Tuj-1) by real-time PCR, western blot, and immunocytochemical staining. The expressions of the astrocyte marker GFAP and neuronal markers NF-M and Tuj-1 increased in neuronal differentiated MSCs (dMSCs). To improve the neuronal differentiation efficiency, PDE4, an important signaling intermediator in the progression of neuronal differentiation, was modulated using well-known inhibitors such as rolipram or resveratrol and then differentiated into neuronal cells (Roli- or RSV-dMSCs). The expressions of NF-M, Tuj-1 were increased while that of GFAP decreased in Roli- and RSV-dMSCs, which were examined by real-time PCR, western blot, and immunocytochemical staining. From these experiments, we have found that the neuronal differentiation efficiency can be ameliorated by the modulation of PDE4 activity.

• The Korean Journal of Physiology and Pharmacology
• /
• v.11 no.6
• /
• pp.239-246
• /
• 2007

Expressions of endoplasmic reticulum stress response (ERSR) genes were examined during the neuronal differentiation of rat fetal cortical precursor cells (rCPC) and rat pheochromocytoma PC12 cells. When rCPC were differentiated into neuronal cells for 7 days, early stem cell marker, nest in, expression was decreased from day 4, and neuronal markers such as neurofilament-L, -M and Tuj1 were increased after day 4. In this condition, expressions of BIP, ATF6, and phosphorylated PERK as well as their down stream signaling molecules such as CHOP, ATF4, XBP1, GADD34, Nrf2 and $p58^{IPK}$ were significantly increased, suggesting the induction of ERSR during neuronal differentiation of rCPC. ERSR was also induced during the differentiation of PC12 cells for 9 days with NGF. Neurofilament-L transcript was time-dependently increased. Both mRNA and protein levels of Tuj1 were increased after the induction, and the significant increase in NeuN was observed at day 9. Similar to the expression patterns of neuronal markers, BIP/GRP78 and CHOP mRNAs were highly increased at day 9, and ATF4 mRNA was also increased from day 7. These results strongly suggest the induction and possible role of ERSR in neuronal differentiation process. Further study to identify targets responsible for neuronal induction will be necessary.

• Journal of Life Science
• /
• v.26 no.1
• /
• pp.8-16
• /
• 2016

Reactive oxygen species (ROS), at appropriate concentrations, mediate various normal cellular functions, including defense against pathogens, signal transduction, cellular growth, and gene expression. A recent study demonstrated that ROS and ROS-generating NADPH oxidase (Nox) are important in self-renewal and neuronal differentiation of subventricular zone (SVZ) neural stem cells in adult mouse brains. In this study, we found that endogenous ROS were detected in SVZ neural stem cells cultured from postnatal mouse brains. Nox4 was predominantly expressed in cultured cells, while the levels of the Nox1 and Nox2 transcripts were very low. In addition, the Nox4 gene was highly upregulated (by up to 10-fold) during neuronal differentiation. Immunocytochemical analysis detected the Nox4 protein mainly in neurons positive for the neuronal specific tubulin Tuj1. After differentiation, endogenous ROS were detected exclusively in neuron-like cells with processes. In addition, perturbation of the cellular redox state with N-acetyl cysteine, a ROS scavenger, during neuronal differentiation greatly inhibited neurogenesis. Lastly, knockdown of Nox4 using short hairpin RNA decreased neurogenesis. These findings suggest that Nox4 may be a major ROS-generating enzyme in postnatal SVZ neural stem cells, and Nox4-mediated ROS generation may be important in their neuronal differentiation.

• BMB Reports
• /
• v.28 no.4
• /
• pp.316-322
• /
• 1995

The GTPase activating protein (GAP) can function both as a negative regulator and an effector of $p21^{ras}$. Overexpression of GAP in NIH-3T3 cells has been shown to inhibit transformation by ms or src. To investigate the function of GAP in a differentiative system, we overexpressed this protein in the nerve growth factor (NGF)-responsive PC12 cell line. Two-fold overexpression of GAP caused a delay of several days in the onset of NGF- but not FGF-induced neuronal differentiation of PC12 cells. However, the NGF-induced activation or tyrosine phosphorylation of upstream (Trk, PLC-${\gamma}1$, SHC) and downstream (B-Raf and $p44^{mapk/erk1}$) components of $p21^{ras}$, signalling cascade was not altered by GAP overexpression. Therefore, the change of phenotype induced by GAP was probably not due to GAP functioning as a negative regulator of $p21^{ras}$. Rather, we found that NGF-induced tyrosine phosphorylation of SNT, a specific target of neurotrophin-induced tyrosine kinase activity, was inhibited by GAP overexpression. SNT is thought to function upstream or independent of $p21^{ras}$. Thus in PC12 cells, overexpressed GAP may control the rate of neuronal differentiation through a pathway involving SNT rather than the $p21^{ras}$ signalling pathway.

• Biomolecules & Therapeutics
• /
• v.18 no.4
• /
• pp.386-395
• /
• 2010

Bone marrow-derived mesenchymal stem cells (BM-MSC) are a multipotent cell population that can differentiate into neuron-like cells. Previously it has been reported that murine BM-MSC can differentiate into neuron-like cells by co-treatment with a Rho-associated kinase (ROCK) inhibitor -Y27632 and $CoCl_2$. In this study, we compared several ROCK inhibitors for the ability to induce human BM-MSCs to differentiate into neuron-like cells in the presence of $CoCl_2$. Y27632 with high specificity for ROCK at 1-30 ${\mu}M$ was best at inducing neuronal differentiation of MSCs. Compared to HA1077 and H1152, which also effectively induced morphological change into neuron-like cells, Y27632 showed less toxicity even at 100 ${\mu}M$, and resulted in longer multiple branching processes at a wide range of concentrations at 6 h and 72 h post-induction. H89, however, which has less specificity by inhibition of protein kinase A, S6 kinase 1 and MSK1 with similar or greater potency, was less effective at inducing neuronal differentiation of MSCs. Simvastatin, which can inhibit Rho, Ras, and Rac by blocking the synthesis of isoprenoid intermediates, showed little activity for inducing morphological changes of MSCs into neuron-like cells. Accordingly, the expression patterns for neuronal cell markers,including ${\beta}$-tubulin III, neuron-specific enolase, neurofilament, and microtubule-associated protein, were consistent with the pattern of the morphological changes. The data suggest that the ROCK inhibitors with higher specificity are more effective at inducing neuronal differentiation of MSCs.

• BMB Reports
• /
• v.44 no.12
• /
• pp.799-804
• /
• 2011

Gangliosides play an important role in neuronal differentiation processes. The regulation of ganglioside levels is related to the induction of neuronal cell differentiation. In this study, the ST8Sia5 gene was transfected into mESCs and then differentiated into neuronal cells. Interestingly, ST8Sia5 gene transfected mESCs expressed GQ1b by HPTLC and immunofluorescence analysis. To investigate the effects of GQ1b over-expression in neurogenesis, neuronal cells were differentiated from GQ1b expressing mESCs in the presence of retinoic acid. In GQ1b expressing mESCs, increased EBs formation was observed. After 4 days, EBs were co-localized with GQ1b and nestin, and GFAP. Moreover, GQ1b co-localized with MAP-2 expressing cells in GQ1b expressing mESCs in 7-day-old EBs. Furthermore, GQ1b expressing mESCs increased the ERK1/2 MAP kinase pathway. These results suggest that the ST8Sia5 gene increases ganglioside GQ1b and improves neuronal differentiation via the ERK1/2 MAP kinase pathway.

• Molecules and Cells
• /
• v.38 no.9
• /
• pp.806-813
• /
• 2015

Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by mutations in the glucocerebrosidase gene (GBA), which encodes the lysosomal enzyme glucosylceramidase (GCase). Deficiency in GCase leads to characteristic visceral pathology and lethal neurological manifestations in some patients. Investigations into neurogenesis have suggested that neurodegenerative disorders, such as GD, could be overcome or at least ameliorated by the generation of new neurons. Bone marrowderived mesenchymal stem cells (BM-MSCs) are potential candidates for use in the treatment of neurodegenerative disorders because of their ability to promote neurogenesis. Our objective was to examine the mechanism of neurogenesis by BM-MSCs in GD. We found that neural stem cells (NSCs) derived from a neuronopathic GD model exhibited decreased ability for self-renewal and neuronal differentiation. Co-culture of GBA-deficient NSCs with BM-MSCs resulted in an enhanced capacity for self-renewal, and an increased ability for differentiation into neurons or oligodendrocytes. Enhanced proliferation and neuronal differentiation of GBA-deficient NSCs was associated with elevated release of macrophage colony-stimulating factor (M-CSF) from BM-MSCs. Our findings suggest that soluble M-CSF derived from BM-MSCs can modulate GBA-deficient NSCs, resulting in their improved proliferation and neuronal differentiation.