Recombinant human nerve growth factor ( rhNGF-β ) gene transfer promotes regeneration of crush-injured mental nerve in rats

• Published in: Oral surgery, oral medicine, oral pathology and oral radiology oral medicine, oral pathology and oral radiology, 2012-03, Vol.113 (3), p.e26-e34
• Main Authors: Li, Bo-Han, DDS, Kim, Soung-Min, DDS, PhD, Yoo, Sang Bae, PhD, Kim, Myung-Jin, DDS, PhD, Jahng, Jeong Won, PhD, Lee, Jong-Ho, DDS, PhD
• Format: Article
• Language: English
• Subjects: Adenoviridae; Animals; Dentistry; Gene Transfer Techniques; Genetic Vectors; Humans; Mandibular Nerve - surgery; Nerve Crush; Nerve Growth Factor - biosynthesis; Nerve Growth Factor - genetics; Nerve Regeneration - drug effects; Nerve Regeneration - genetics; Rats; Rats, Sprague-Dawley; Receptor, trkA - biosynthesis; Receptor, trkA - genetics; Receptors, Nerve Growth Factor - biosynthesis; Receptors, Nerve Growth Factor - genetics; Recombinant Proteins - genetics; Sensory Receptor Cells - physiology; Surgery; Trigeminal Ganglion - metabolism; Trigeminal Nerve Injuries - surgery
• ISSN: 2212-4403; 2212-4411
• DOI: 10.1016/j.tripleo.2011.07.002

Objective The aim of this study was to evaluate whether the recombinant human nerve growth factor ( rhNGF- β) gene transfer at a crush-injured sensory nerve can enhance nerve regeneration. Study Design A 4-mm crush injury was made on the mental nerve of mandible in rats, and rhNGF-β adenovirus (6 μL, concentration = 1.0 × 1011 pfu/μL) was injected at the crushed site for the experimental group (NGF-Ad group, n = 15) and the same volume of PBS for the controls (PBS group, n = 15). A sham group of uninjured nerve was also used for the normal control (Sham group, n = 15). The effect of rhNGF-β adenovirus injection was evaluated by real-time reverse trascriptase polymerase chain reaction for the quantification of nerve growth factor (NGF), low-affinity NGF receptor (p75NTR), and its tyrosine receptor kinase A (trkA) mRNA expression at the trigeminal ganglion (TG) 5 days after injection. Nerve regeneration was evaluated with sensory test, retrograde axonal transport in the TG, and histomorphometric study for 4 weeks. Results NGF, p75NTR, and trkA mRNA expression was significantly increased at the TG 5 days after injection of rhNGF-β adenovirus ( P < .05). The NGF-Ad group showed improved sensory recovery ( P < .05), and the number of retrograde-labeled sensory neurons and soma size of TG were larger compared with the PBS groups ( P < .05). Histomorphometrically, the myelinated axon number, myelin thickness, and G-ratio in the NGF-Ad group was also significantly higher than the PBS groups ( P < .05). Conclusions Recombinant human nerve growth factor gene transfer promoted regeneration of crush-injured mental nerve.