Rat Facial Nerve Regeneration with Human Immature Dental Pulp Stem Cells

Abstract

Facial paralysis can result in severe implications for the patients. However, stem cell biology has become an important field in regenerative medicine since the discovery and characterization of mesenchymal stem cells. Our aim was to evaluate the regeneration after facial nerve crush injury and application of human immature dental pulp stem cells (iDPSC). For this study 70 Wistar rats underwent a unilateral facial nerve crush injury and were divided into two groups: Group I (GI): Crushed; Group II (GII): Crushed and iDPSC, and distributed into study periods of 3, 7, 14, 21, and 42 postoperative days. Facial nerve regeneration was analyzed via functional recovery of whisker movement, histomorphometric analysis, and immunoblotting assay. The results show that GII had complete functional recovery at 14 days, while GI recovered after 42 days. Also, regarding the facial nerve trunk, GII presented histological improvement, evidencing better axonal and structural organization of the myelin sheath, and exhibited statistically higher values for the outer and inner perimeters and g-ratio. Nevertheless, GI exhibited statistically higher values for the thickness of myelin sheath. In the buccal branch, no differences were observed for all parameters between groups. At 42 days, both groups GI and GII were close to the levels observed for the control group. Concerning nerve growth factor expression, GII exhibited statistically greater values (p < 0.05) compared with the control group at 7 days. In summary, a single injection of human iDPSC promoted a positive effect on regeneration of the facial nerve trunk after 14 days and provided an alternative to support regeneration following peripheral nerve injury.

Dental Tissue-Derived Human Mesenchymal Stem Cells and Their Potential in Therapeutic Application

“…Dental MSCs also hold promise for the treatment of facial nerve injury. Recent experimental evidence showed that a novel method to treat crush injury of rats' facial nerve is via a single application of human SHEDs immediately, which could promote a positive local effect on neuroprotection and remyelination in 2 weeks [ 104 ].…”

Potential Therapeutic Strategies and Substances for Facial Nerve Regeneration Based on Preclinical Studies

“…Cultured dental pulp-derived cells, which also produce neurotrophic factors such as NGF, BDNF and GDNF, also displayed better therapeutic effects on peripheral nerve regeneration [ 46 , 47 ]. In addition, immature human DPCs have been shown to modulate the effects of proinflammatory cytokines, with increased levels of the anti-inflammatory cytokines IL-6 and IL-10 and reduced levels of proinflammatory factors such as IL-2, IL-4, TNF-α, and IFN-γ [ 48 ]. Immature human DPCs were also shown to affect the migration of Schwann cells into the target tissue and their subsequent proliferation, resulting in the production of several types of trophic factors, including neurotrophins, providing a favorable microenvironment for regeneration [ 49 ].…”

Biossegurança Na Prática Odontológica: Desafios Emergentes Durante a Pandemia De Covid-19

“…No atual contexto das terapias regenerativas, entre todas as DSC (Figura 1), as que apresentam um maior potencial terapêutico e que são mais utilizadas para fins de pesquisas são células-tronco derivadas da polpa dental de dentes decíduos esfoliados (SHED) ou permanentes (DPSC) (FUJII et al, 2015;SAEZ et al, 2019;TANIKAWA et al, 2020). Estas possuem uma ampla capacidade de se diferenciarem em diversas linhagens celulares e um grande potencial regenerativo, imunomodulador e anti-inflamatório (FUJII et al, 2015;SOARES et al, 2019).…”