[In vitro neurite outgrowth induced by BDNF and GDNF in combination with dexamethasone on cultured spiral ganglion cells].

Abstract

BACKGROUND:

The efficacy of cochlear implant performance depends, among many other factors, on the number of excitable spiral ganglion cells (SGCs) and the nerve-electrode interface. In earlier animal studies it has been demonstrated that neurotrophic factors are effective to improve SGC survival after experimentally induced deafness. With regard to their anti-inflammatoric and anti-proliferative effects, glucocorticoids (e. g. dexamethasone) are potentially interesting therapeutic agents to reduce connective tissue formation around the inserted electrode. The biological effects of a combined intervention of neurotrophic factors with steroids on SGCs are unknown. Therefore the objective of the study was to investigate possible trophic or even toxic effects of brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and dexamethasone on neurite outgrowth of cultivated SGCs.

METHODS:

By using dissociated postnatal spiral ganglion cells (p3-5) for cultivation in the present study, the influence of the mentioned factors in various concentrations and combinations on neurite outgrowth of SGCs was analysed.

RESULTS:

Our results indicate significant trophic effects for BDNF (50 ng/ml) and a combination of BDNF with dexamethasone (100 ng/ml) on SGC neurite outgrowth. In contrast, single application of GDNF or dexamethasone in different concentrations caused no significant changes on neurite outgrowth when compared to the control condition.

CONCLUSIONS:

Neurite outgrowth induced by neurotrophic factors could not be observed to be reduced when dexamethasone is given at the same time. Therefore the demonstrated results provide a basis for further animal studies in this field of research.

• Authors: T Stöver, V Scheper, M Diensthuber, T Lenarz, P Wefstaedt
• Journal: Laryngo- rhino- otologie (Laryngorhinootologie) Vol. 86 Issue 5 Pg. 352-7 (May 2007) ISSN: 0935-8943 [Print] Germany
• Vernacular Title: Neuritenwachstum in vitro durch BDNF und GDNF in Kombination mit Dexamethason auf kultivierte Spiralganglienzellen.
• PMID: 17163378 (Publication Type: Comparative Study, English Abstract, Journal Article)

Chemical References

• Brain-Derived Neurotrophic Factor
• Drug Combinations
• Glial Cell Line-Derived Neurotrophic Factor
• Glucocorticoids
• Dexamethasone

Topics

• Animals
• Brain-Derived Neurotrophic Factor (administration & dosage, pharmacology)
• Dexamethasone (administration & dosage, pharmacology)
• Drug Combinations
• Glial Cell Line-Derived Neurotrophic Factor (administration & dosage, pharmacology)
• Glucocorticoids (administration & dosage, pharmacology)
• Neurites (drug effects)
• Rats
• Rats, Sprague-Dawley
• Research
• Spiral Ganglion (cytology, drug effects)
• Time Factors