Effect of glucocorticoids on expression of cutaneous antimicrobial peptides in northern leopard frogs (Lithobates pipiens)

BMC Veterinary Research

Jeff L. Caswell²  Mary Ellen Clark²  Ian K. Barker²  Claire Jardine²  Ray Lu¹  Louise A. Rollins-Smith³  Laetitia Tatiersky² 

[1] Department of Molecular and Cellular Biology, University of Guelph, Guelph N1G 2W1, ON, Canada;Department of Pathobiology, University of Guelph, Guelph N1G 2W1, ON, Canada;Department of Biological Sciences, Vanderbilt University, Nashville 37232, TN, USA

关键词: Quantitative RT-PCR;    Corticosteroid;    Frogs;    Skin;    Antimicrobial peptides;    Chytridiomycosis;   

Others  :  1224381
DOI  :  10.1186/s12917-015-0506-6

 received in 2014-10-10, accepted in 2015-07-24,  发布年份 2015

【 摘 要 】

Background

Many species of frogs secrete cutaneous antimicrobial peptides that are capable of killing Batrachochytrium dendrobatidis. Some of these species are nonetheless susceptible to chytridiomycosis, suggesting that host factors causing dysregulation of this innate immune response may be important in pathogenesis. Since stresses, such as from environmental perturbations, are a potential cause of such dysregulation, this study investigated the effect of glucocorticoid on cutaneous gene expression of these antimicrobial peptides.

Results

Northern leopard frogs (Lithobates pipiens) were injected with either the corticosteroid methylprednisolone or saline every 48 h. Norepinephrine-elicited cutaneous secretions were collected every 8 days for 40 days. Gene expression of antimicrobial peptides (brevinin-1P and ranatuerin-2P) in the cutaneous secretions was measured relative to the reference genes EF1-α and RPL8 using quantitative RT-PCR. Corticosteroid treatment was associated with a significant increase in brevinin-1P gene expression, which was most notable at 24–40 days of corticosteroid administration. Ranatuerin-2P expression followed a similar but non-significant trend.

Conclusion

This treatment protocol, including corticosteroid-administration and frequent norepinephrine-induced secretion, increased AMP gene expression in the skin of L. pipiens under these experimental conditions. The findings do not support the hypothesis that environmental stress predisposes frogs to chytridiomycosis by causing glucocorticoid-induced suppression of antimicrobial peptide defences.

【 授权许可】

   
2015 Tatiersky et al.

【 图 表 】

Fig. 1.

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