Human cerebral spheroids undergo 4‑aminopyridine‑induced, activity associated changes in cellular composition and microRNA expression

Parmentier T, James FMK, Hewitson E, Bailey C, Werry N, Sheridan SD, Perlis RH, Perreault ML, Gaitero L, Lalonde J, LaMarre J.

Scientific Reports, 2022.


Scientists use Axion’s bioelectronic assays to explore neurogenesis in 3D cerebral spheroids derived from human induced pluripotent stem cells.

Activity-induced neurogenesis is not fully understood, in part due to a historic lack of in vitro models that accurately reflect the complexity of the human brain. More recently, however, three-dimensional cerebral spheroids derived from human induced pluripotent stem cells (iPSCs) are enabling scientists to recapitulate key elements of human brain development overtime and explore mechanisms underlying complex biological processes. In this study, researchers examine neuronal activity and neurogenesis in cerebral spheroids treated with 4-aminopyridine (4AP)–an organic compound shown to increase neuronal activity in research applications and used clinically as a muscle strengthener for multiple-sclerosis, spinal cord injury, and other conditions. The authors also investigated the role of micro-RNAs associated with neurogenesis in vivo.

To explore neuronal activity in the iPSC-derived cerebral spheroids incubated with 4AP in vitro, the scientists used Axion’s label-free Maestro multielectrode array (MEA) platform. The results demonstrated that 4AP increases neuronal activity and the number of new neurons in 90-day-old cerebral spheroids while decreasing glial cells, and showed that 160-day-old cerebral spheroids form mature neuronal networks with synchronization. The authors also revealed a decrease in the expression of miR-135a exposed to 4AP—a finding that supports previous studies showing that activity reducesmiR135a. Overall, these results demonstrate that iPSC-derived cerebral spheroids are a promising model for examining activity-induced neurogenesis and may enable new insights into the pathogenesis and progression of neurological disorders.