title: The effects of repetitive transcranial magnetic stimulation on proliferation and differentiation of neural stem cells.
abstract: Repetitive transcranial magnetic stimulation (rTMS) is a new method for treating many neurological conditions; however, the exact therapeutic mechanisms behind rTMS-induced plasticity are still unknown. Neural stem and progenitor cells (NS/PCs) are active players in brain regeneration and plasticity but their behavior in the context of rTMS therapy needs further elucidation. We aimed to evaluate the effects of rTMS on proliferation and differentiation of NS/PCs in the subventricular zone (SVZ) of adult mouse brain. Adult male mice (n=30) were divided into rTMS (1-Hz and 30-Hz) and sham groups and treated for 7 or 14 consecutive days. Harvested NS/PCs from the SVZ were cultured in the neurosphere assay for 8 days and the number and size of the resulting neurospheres as well as their in vitro differentiation capacity were evaluated. After one week of rTMS treatment at 1-Hz and 30-Hz compared with sham stimulation, the mean neurosphere forming frequency per brain was not different while this measure significantly increased after two weeks (P<0.05). The mean neurosphere diameter in 1-Hz treatment paradigm was significantly larger compared with sham stimulation at both 1 and 2 weeks. In contrast, 30-Hz treatment paradigm resulted in significantly larger neurospheres only after 2 weeks. Importantly, rTMS treatment at both frequencies increased neuronal differentiation of the harvested NS/PCs. Furthermore, one week in vitro rTMS treatment of NS/PCs with both 1-Hz and 30-Hz increased NS/PCs proliferation and neuronal differentiation. It is concluded that both 1-Hz and 30-Hz rTMS treatment increase NS/PCs proliferation and neuronal differentiation.
authors.affiliation: Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran. ; Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Keramatollah
authors.initials: K
authors.lastname: Abbasnia
authors.affiliation: Neural Stem Cell and Regenerative Neuroscience Laboratory, Department of Anatomical Sciences, Shiraz School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Ghanbari
authors.affiliation: Neural Stem Cell and Regenerative Neuroscience Laboratory, Department of Anatomical Sciences, Shiraz School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mehrnaz
authors.initials: M
authors.lastname: Abedian
authors.affiliation: Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Ghanbari
authors.affiliation: Department of Physical Therapy, College of Public Health and Health Professions, University of Florida, Gainesville, FL, USA.
authors.forename: Sharareh
authors.initials: S
authors.lastname: Sharififar
authors.affiliation: Neural Stem Cell and Regenerative Neuroscience Laboratory, Department of Anatomical Sciences, Shiraz School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. ; Neural Stem Cell and Regenerative Neuroscience Laboratory, Shiraz Stem Cell Institute, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Azari
keywords: Neural stem and progenitor cells; Neurosphere assay; Proliferation; Subventricular zone; rTMS