Ecdysteroids are present in the blood of wild passerine birds

Sándor Hornok,Attila Csorba,Attila Hunyadi,Tibor Csörgő,Dávid Kováts

doi:10.1038/s41598-019-53090-9

Sándor Hornok, Attila Csorba + Show 3 more

Open Access

https://doi.org/10.1038/s41598-019-53090-9

Copy DOI

Abstract

Ecdysteroids (arthropod molting hormones) play an important role in the development and sexual maturation of arthropods, and they have been shown to have anabolic and “energizing” effect in higher vertebrates. The aim of this study was to assess ecdysteroid diversity, levels according to bird species and months, as well as to observe the molting status of hard ticks (Acari: Ixodidae) infesting the birds. Therefore, blood samples and ticks were collected from 245 birds (244 songbirds and a quail). Mass spectrometric analyses showed that 15 ecdysteroids were regularly present in the blood samples. Molting hormones biologically most active in insects (including 20-hydroxyecdysone [20E], 2deoxy-20E, ajugasterone C and dacryhainansterone) reached different levels of concentration according to bird species and season. Similarly to ecdysteroids, the seasonal presence of affected, apolytic ticks peaked in July and August. In conclusion, this study demonstrates the presence of a broad range and high concentrations of ecdysteroids in the blood stream of wild-living passerine birds. These biologically active, anabolic compounds might possibly contribute to the known high metabolic rate of songbirds.

Highlights

Ecdysteroids play an important role in the development and sexual maturation of arthropods, and they have been shown to have anabolic and “energizing” effect in higher vertebrates
Ecdysteroids do not necessarily bind to homologous receptors in different phyla of the Animal Kingdom, they may have a variety of effects even in distantly related taxa. These compounds play an important role in molting and development of pre-adult stages, as well as in the sexual maturation of adult arthropods3, but they were experimentally shown to have anabolic effect in mammals4 and galliform birds5
Some bird species differed from others in the seasonality of cardinal ecdysteroids: 2-deoxy-20E [5] and ajugasterone C [6] were absent in samples of Turdus merula during most of the spring and summer months, while these compounds were present in samples of T. philomelos and Prunella modularis only at the beginning of the sampling period (Fig. 1)

Summary

Introduction

Ecdysteroids (arthropod molting hormones) play an important role in the development and sexual maturation of arthropods, and they have been shown to have anabolic and “energizing” effect in higher vertebrates. This study demonstrates the presence of a broad range and high concentrations of ecdysteroids in the blood stream of wild-living passerine birds These biologically active, anabolic compounds might possibly contribute to the known high metabolic rate of songbirds. Steroids are biologically active organic molecules widely present in multicellular eukaryotes These compounds play an important role in the regulation of reproduction, development and responses to environmental stimuli of plants, fungi and animals. Ecdysteroids do not necessarily bind to homologous receptors in different phyla of the Animal Kingdom, they may have a variety of effects even in distantly related taxa These compounds play an important role in molting and development of pre-adult stages, as well as in the sexual maturation of adult arthropods, but they were experimentally shown to have anabolic effect in mammals and galliform birds. The aim of this study was to broaden the scope of these preliminary observations and to examine their relevance in a broader context: i.e., to evaluate ecdysteroid diversity, peak levels and potential effects on bird-infesting ticks (a) in a larger set of bird samples, and (b) with a more extended and more sensitive mass spectrometric analysis

Objectives

Methods

Results

Conclusion