Electrical stimulation (E-stim) is known to modulate neural activity and circuit function, promote neuroplasticity, and facilitate neural repair through its ability to activate or inhibit specific brain regions. Controlling E-stim's activation and inhibition functions has become increasingly important for advancing therapeutic strategies in neurodegenerative diseases and neural regeneration. To this end, understanding how E-stim influences stem cell behavior, particularly in terms of proliferation and differentiation, is critical for harnessing its potential in regenerative medicine.

This study investigates the effects of electrical stimulation on the differentiation and proliferation potential of Adult Hippocampal Progenitor Cells (AHPC) neurospheres, with an additional focus on comparing the biocompatibility and impact of smooth versus nanoelectrode devices. AHPC neurospheres were cultured on each device and subjected to 1 Hz biphasic E-stim at 20 and 40 mV for 10 minutes over 5 days in vitro. The differentiation of AHPCs was assessed using immunocytochemistry with a panel of cell-type-specific antibody markers. Fluorescence microscopy was employed to visualize the immunolabeled and 4′,6-diamidino-2-phenylindole dihydrochloride (DAPI)-stained cells, which were then quantified.

Thus far, three biological replicates were performed using beta-III tubulin (TuJ1) antibody, which indicates immature neurons. Preliminary results from these quantified biological replicates, analyzed with ImageJ software, reveal that 20 mV E-stim significantly enhanced neuronal differentiation, as indicated by an increase in TuJ1-positive cells, compared to the control and 40 mV conditions. Both smooth and nanoelectrode devices demonstrated biocompatibility, with no significant adverse effects on AHPC neurospheres. Future work will expand on these findings by incorporating additional neuronal markers, such as microtubule-associated protein 2a,b (MAP2ab), and glial markers like glial fibrillary acidic protein (GFAP). Additionally, gene expression analysis via qPCR will be explored to further elucidate the molecular mechanisms underlying AHPC differentiation and proliferation in response to E-stim. This work holds promise for advancing regenerative therapies in neurodegenerative conditions.