Biphasic Electrical Currents Stimulation Promotes both Proliferation and Differentiation of Fetal Neural Stem Cells

The use of non-chemical methods to differentiate stem cells has attracted researchers from multiple disciplines, including the engineering and the biomedical fields. No doubt, growth factor based methods are still the most dominant of achieving some level of proliferation and differentiation control - however, chemical based methods are still limited by the quality, source, and amount of the utilized reagents. Well-defined non-chemical methods to differentiate stem cells allow stem cell scientists to control stem cell biology by precisely administering the pre-defined parameters, whether they are structural cues, substrate stiffness, or in the form of current flow. We have developed a culture system that allows normal stem cell growth and the option of applying continuous and defined levels of electric current to alter the cell biology of growing cells. This biphasic current stimulator chip employing ITO electrodes generates both positive and negative currents in the same culture chamber without affecting surface chemistry. We found that biphasic electrical currents (BECs) significantly increased the proliferation of fetal neural stem cells (NSCs). Furthermore, BECs also promoted the differentiation of fetal NSCs into neuronal cells, as assessed using immunocytochemistry. Our results clearly show that BECs promote both the proliferation and neuronal differentiation of fetal NSCs. It may apply to the development of strategies that employ NSCs in the treatment of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases

Biphasic Electrical Currents Stimulation Promotes both Proliferation and Differentiation of Fetal Neural Stem Cells

The use of non-chemical methods to differentiate stem cells has attracted researchers from multiple disciplines, including the engineering and the biomedical fields. No doubt, growth factor based methods are still the most dominant of achieving some level of proliferation and differentiation control - however, chemical based methods are still limited by the quality, source, and amount of the utilized reagents. Well-defined non-chemical methods to differentiate stem cells allow stem cell scientists to control stem cell biology by precisely administering the pre-defined parameters, whether they are structural cues, substrate stiffness, or in the form of current flow. We have developed a culture system that allows normal stem cell growth and the option of applying continuous and defined levels of electric current to alter the cell biology of growing cells. This biphasic current stimulator chip employing ITO electrodes generates both positive and negative currents in the same culture chamber without affecting surface chemistry. We found that biphasic electrical currents (BECs) significantly increased the proliferation of fetal neural stem cells (NSCs). Furthermore, BECs also promoted the differentiation of fetal NSCs into neuronal cells, as assessed using immunocytochemistry. Our results clearly show that BECs promote both the proliferation and neuronal differentiation of fetal NSCs. It may apply to the development of strategies that employ NSCs in the treatment of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases

Oligomeric Aβ₄₂-induced apoptotic cell death was decreased by increased IL-10 secreted from hASC and/or murine BV2 cells.

<p>(a–c) primary mouse neurons were grown in coated 24-well culture dishes to near confluence 80% in neurobasal media containing B27 for 7 days. They were then added to 10 µM of oligomeric Aβ₄₂ peptides and co-cultured with hASCs and/or BV2 cells. Blocking of IL-10 receptor interaction was performed for 48 h and then LDH and TUNEL assay were performed. A neutralizing IL-10 or IL-10 receptor antibody (5 µg/ml, respectively) was used in the indicated groups. (a) Phase contrast and TUNEL staining of primary neurons treated with 10 µM of oligomeric Aβ₄₂ peptides. The TUNEL-positive cells are stained red. Scale bar, 50 µm. (b, c) Data represent mean ± SEM of three independent experiments (n = 30). Asterisk *, <i>P</i><0.05, **, <i>P</i><0.01, ***, <i>P</i><0.001; by One-Way ANOVA; Tukey’s HSD Post Hoc test.</p

Experimental schemes of intravenous and intracerebral injections.

<p>(a) Experimental scheme of intravenous injection (i.v.). (b) Experimental scheme of intracerebral injection (i.c.).</p

Intravenous and intracerebral injection of hASC reduced the number of amyloid plaques in Tg2576 mouse brains.

<p>(a) Congo red staining for the detection of amyloid plaques was carried out in the hippocampus of each group 4 months after (i.v.) injection. (b) 4 months after the 13^th (i.v.) injection, the number of plaques was counted in the hippocampal region of the Tg-hASC and the Tg-sham group. (c) At 4 months after hASC (i.c.) injection, the number of plaques was counted in the hippocampal region of Tg-hASC and Tg-sham groups. All data are represented as mean ± SEM (n = 9∼15 per group). Asterisk *, <i>P</i><0.05, **, <i>P</i><0.01 by one-way ANOVA.</p

Engrafted hASCs increased endogenous neurogenesis in the brains of Tg2576 mice.

<p>(a) At 3 weeks after (i.c.) injection, the CSF-hASCs still stay at the hippocampal region with mouse Nestin and BrdU positive cells produced around them. (b) At 3 and 6 weeks after (i.c.) injection, PSA-NCAM level was increased in Tg-hASC group. One representative of three separate experiments is shown. (c-d) Immunohistochemical analysis showed significantly increased number of DCX positive cells. (c) Tissues were immunostained with anti-DCX (red) antibody and counterstained with DAPI (blue). Scale bar = 50µm. (d) Quantitative data of DCX positive cells are represented as mean ± SEM of three independent experiments (n = 8). Asterisk *, <i>P</i><0.05 by one-way ANOVA.</p

Intravenous and intracerebral injection of hASC reduced Aβ and APP-CT levels and increased neprilysin in Tg2576 mouse brains.

<p>(a) Western blot analysis was performed with lysates from the cortical region of the brains in each group using 6E10 and GAPDH antibodies 4 months after injection. (b, c) Aβ and CT expressions were normalized with those of APP and GAPDH for quantification (n = 5). (d) Neprilysin level was significantly increased in Tg-hASC group (n = 4). All data are represented as mean ± SEM. Asterisk *, <i>P</i><0.05 by one-way ANOVA.</p