Photobiomodulation regulates adult neurogenesis in the hippocampus in a status epilepticus animal model

Abstract

Status epilepticus (SE) refers to a single seizure that lasts longer than typical seizures or a series of consecutive seizures. The hippocampus, which is vulnerable to the effects of SE, has a critical role in memory storage and retrieval. The trisynaptic loop in the hippocampus connects the substructures thereof, namely the dentate gyrus (DG), CA3, and CA1. In an animal model of SE, abnormal neurogenesis in the DG and aberrant neural network formation result in sequential neural degeneration in CA3 and CA1. Photobiomodulation (PBM) therapy, previously known as low-level laser (light) therapy (LLLT), is a novel therapy for the treatment of various neurological disorders including SE. However, the effects of this novel therapeutic approach on the recovery process are poorly understood. In the present study, we found that PBM transformed SE-induced abnormal neurogenesis to normal neurogenesis. We demonstrated that PBM plays a key role in normal hippocampal neurogenesis by enhancing the migration of maturing granular cells (early neuronal cells) to the GCL, and that normal neurogenesis induced by PBM prevents SE-induced hippocampal neuronal loss in CA1. Thus, PBM is a novel approach to prevent seizure-induced neuronal degeneration, for which light devices may be developed in the future.

Photobiomodulation Attenuated Cognitive Dysfunction and Neuroinflammation in a Prenatal Valproic Acid-Induced Autism Spectrum Disorder Mouse Model

“…In addition to this, NIR shows several neuroprotective effects in animal models with various neurological diseases such as brain stroke and Parkinson's disease [39,40]. Dysregulation of Neurogenesis is caused by the neuroinflammatory response [41], and PBM can promote neurogenesis by stimulating neural progenitor cells [42,43]. Because 830 nm PBM has the lowest absorption rate of water and hemoglobin in tissue, it has better tissue penetration in the deeper range and can reduce nerve damage [44][45][46].…”

Transcranial photobiomodulation for brain diseases: review of animal and human studies including mechanisms and emerging trends

“…Hong et al. observed that tPBM could prevent seizure-induced neuronal degeneration 141 . In summary, the above studies demonstrated that tPBM with NIR light could be potential non-invasive and effective therapeutics for inhibiting epileptogenesis and alleviating epilepsy damage.…”

Photobiomodulation Can Enhance Stem Cell Viability in Cochlea with Auditory Neuropathy but Does Not Restore Hearing

“…In addition, we indirectly demonstrated the effect of PBM on stem cell differentiation using inner ear organoids and transcriptome analysis [33]. Other published papers have also already demonstrated the proneural effects of photobiomodulation on hippocampal neurogenesis [34] and synaptic formation [35]. Therefore, it is necessary to confirm whether the fusion in application of stem cell and PBM can effectively regenerate spiral ganglion neurons.…”