Cells with electrophysiological activity obtained at the UPV/EHU open up new ways to study neurodegenerative diseases and develop future autologous transplants.
A study by the UPV/EHU, published in the prestigious journal Stem Cell Research & Therapy, has proven that stem cells extracted from human dental pulp can be transformed into excitable neuronal-type cells and has shown the potential of these easily accessible cells for nerve tissue engineering. This finding will allow advances in cell therapy to treat various neurodegenerative diseases such as Huntington’s disease and epilepsy.
Adult neurons do not divide, and when they are lost, they cannot regenerate, as the brain, unlike other organs, has a very limited capacity for natural regeneration due to the scarce presence of stem cells. For this reason, the scientific community is actively working on the search for functional neurons that can be transplanted to compensate for deficits caused by neurodegenerative diseases, head injuries, or strokes.
For these transplanted cells to integrate into the damaged brain circuits and effectively replace the lost neurons, they must be capable of generating electrical impulses. In this context, the Signaling Lab research group of the University of the Basque Country (UPV/EHU), led by Gaskon Ibarretxe and José Ramón Pineda, has achieved a significant advance by obtaining, from human dental pulp stem cells, soft tissue inside the tooth cells very similar to neurons, capable of producing electrical impulses like those of natural neurons.
The most important milestone of this study is the achievement, without resorting to genetic modifications, of functionally excitable cells that synthesise neurotransmitters that regulate neuronal activity. Primary dental cells were cultured with only differentiation factors and subjected to precise stimuli, generating cells with neuronal electrophysiological activity, something the researchers say has never been achieved before.
Similar to inhibitory neurons
The cells obtained by the UPV/EHU research group show similar characteristics to inhibitory neurons, as they are capable of synthesising GABA, a neurotransmitter that prevents the receptor neuron from generating electrical impulses. This type of signalling is crucial in pathologies such as Huntington’s disease or epilepsy, where there is a selective loss of inhibitory neurons, leading to hyperexcitability in the affected brain circuits. The researchers highlight the importance of this finding, as it could offer an innovative way to restore balance in damaged brain areas and compensate for the functional loss caused by these diseases.
Ibarretxe and Pineda, professors at the UPV/EHU’s Department of Cell Biology and Histology, stress that this discovery poses a different approach to traditional cell therapies, which until now focused mainly on protecting or preserving what still worked, without replacing the lost cells. The next step will be to transplant these cells into animal models to test whether they can integrate into existing neural circuits and form functional connections. Although the cells generated are not yet fully mature, their potential plasticity and stability, as well as their low propensity to form tumours, underpin their possible future clinical use. The researchers acknowledge that there is still a long way to go, but consider that this line of work opens new doors towards personalised and regenerative medicine for the nervous system.
