The Effect of Slow‐Release bFGF with Gelatin on Anosmia Mice

Abstract

Objective: Basic fibroblast growth factor (bFGF) may regenerate the olfactory system. However, it does not work well because of short acting time. We developed a new drug delivery system by embedding bFGF in a gelatin hydrogel that degrades slowly. This study is designed to identify the effects of bFGF-hydrogel in anosmia mice. Method: An anosmia mouse model was induced by i.p. injection of 3-methylindole. The animals were divided into four groups by the following procedures: group A, no further treatment; B, single intranasal administration of bFGF; C, single intranasal administration of PBS-hydrogel; D, single intranasal administration of bFGF-hydrogel. A month later, we evaluated by behavioral observations and histological findings. Results: The results for groups A, B, and C were similar in all investigations. In contrast, group D revealed better results; behavior observation showed improvement of olfactory loss and, in histological study, the thickness of olfactory epithelium and the number of Olfactory Marker Protein (OMP)-immunoreactive cells increased after a month. These results indicated the efficacy of single intranasal administration of embedding bFGF in hydrogel for impaired olfactory function. Conclusion: This preliminary study revealed the efficacy of a bFGF-impregnated biodegradable hydrogel as a drug-delivery medium in the olfactory mucosa. Single intranasal administration of embedding bFGF in hydrogel facilitates faster healing from olfactory dysfunction. Further studies are necessary to fully evaluate the usefulness of this procedure.