Utilization of Adipose-Derived Stem Cells in Cranial Nerve Regeneration: A Comprehensive Review.

Large peripheral nerve injuries may require surgical reconnection. Cell-based therapies have also been investigated for nerve regeneration. Within the context of this modern treatment paradigm for peripheral nerve injuries, we investigated the role of adipose-derived stem cells (ADSCs) in the regeneration of cranial nerves. PubMed and Embase databases were used to search for primary studies reporting the use of ADSCs in the regeneration of cranial nerves. A total of 12 studies were included, all of which presented data on specific neural injury, therapy, and functional outcomes. Eight studies focused on the facial nerve (66.7%), two on the optic nerve (16.7%), one on the olfactory nerve (8.3%), and one on the hypoglossal nerve (8.3%). One study applied ADSCs to human cranial nerve injuries, while the remainder studied animal models. In these studies, ADSC groups had higher numbers of myelinated fibers, increased myelin thickness, and diameter of muscle fibers, as well as greater magnitude of compound muscle action potentials (CMAP) when compared to controls. In studies focused on optic nerve regeneration, significant improvements across visual tests were observed. ADSCs demonstrate potential utility in regard to their ability to facilitate functional recovery of cranial nerves in humans and animal models. As such, this therapy merits further investigation so that its true clinical applications can be determined.