The effect of basic fibroblast growth factor on the regeneration of guinea pig olfactory epithelium

Abstract

Olfactory receptor cells are widely thought to regenerate after degeneration and also thought to show turnover in normal circumstances in animal olfactory epithelium. The identity of the factor that controls proliferation and differentiation of olfactory receptor cells is a very important problem that has yet to be resolved. In this study, the mitogenic effects of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on olfactory receptor cells in guinea pig olfactory epithelium was examined. The intraperitoneal injection of 1,000 ng bFGF/day for 14 days increased the cells in proliferation detected by immunostaining with proliferating cell nuclear antigen (PCNA), while neither EGF nor low-dose bFGF had any effect. These results support the idea that an adequate dose of bFGF plays an important role in the neurogenesis in the olfactory epithelium. Further study is needed to clarify the efficacy of bFGF in the damaged olfactory epithelium, but bFGF may provide a therapeutic option for olfactory disturbances caused by complete or partial loss of olfactory receptor cells.

Effect of intranasal administration of concentrated growth factors on regeneration of the olfactory epithelium in an olfactory dysfunction-induced rat model

“…Therefore, CGFs can be placed in the intact olfactory fissure without causing bleeding or pain. In basic research, methods of supplying growth factors to the OE have included intranasal drip infusion of bFGF [ 12 ] and administration using gelatin hydrogel [ 43 ], which is a drug delivery system that involves embedding a medicine. In particular, the administration of gelatin hydrogels is more effective than intranasal drip infusion in promoting olfactory epithelial regeneration [ 13 , 44 ]; however, gelatin hydrogels have not been clinically applied to patients with olfactory dysfunction.…”

“…Regenerated ORNs extend their axons into the olfactory bulb (OB) and reassemble synapses with the mitral cells in the OB, thereby regenerating the olfactory conduction tract [ 9 ]. Animal models have shown that olfactory neuron regeneration is induced by neurotrophins, such as nerve growth factor (NGF) [ 10 ] and brain-derived neurotrophic factor (BDNF) [ 11 ], and growth factors such as basic fibroblast growth factor (bFGF) [ 12 ], insulin-like growth factor (IGF) [ 13 ], and transforming growth factor-α (TDF-α) [ 14 ]. The promotion of regeneration in the OE by these growth factors is expected to lead to the treatment of olfactory dysfunction [ 15 ].…”

Treatment of Neural Anosmia by Topical Application of Basic Fibroblast Growth Factor–Gelatin Hydrogel in the Nasal Cavity

“…3 In cases of peripheral nerve injury, bFGF has been shown to facilitate recovery from the nerve damage by preventing nerve degeneration and promoting neuronal regrowth. 18 In an experimental study with guinea pigs, Nakamura et al 19 reported that intraperitoneal injection of bFGF effectively facilitated regeneration of the olfactory epithelium. The effects were dose dependent: a higher dose of bFGF showed more distinct effects.…”

Basal cells express functional TRPV4 channels in the mouse nasal epithelium

“…The basal cells have stemness/progenitor characteristics and play essential roles in epithelial remodeling [2] . Both the OE and AE have indirect contact with the external environment and many factors, including injury, mechanical stress, transcription factors and growth factors, regulate their neurogenesis and epithelial regeneration [3] , [4] , [5] , [6] , [7] , [8] , [9] . Thus, determining which receptors and sensors are expressed in these basal cells could contribute to the understanding of their function and regulation.…”