Biology subjects

Hornok, S.

Publications and source records attributed to Hornok, S..

2 recordsLinked to original sources

bioRxiv2021

Ecdysteroids as natural doping substances in the blood of insectivorous bats

Bats have deserved much scientific attention due to their biological-ecological properties and increasingly recognized epidemiological significance. Ecdysteroids are insect-molting hormones that (under experimental conditions) have stimulating and anabolic effects in mammals, including humans. Therefore, these biologically active compounds are currently under consideration by the World Anti-Doping Agency (WADA) to become doping-controlled substances. Previously we demonstrated that low to high concentrations of ecdysteroids appear in the blood of insectivorous passerine birds. Since passerine birds and echolocating bats share several adaptive mechanisms in connection with flying, and insectivorism is also among their common traits, we hypothesized that ecdysteroids might also be present in the blood of insectivorous bats. To test this hypothesis, blood samples of eight insectivorous bat species were collected and analyzed for the presence of ecdysteroids with highly sensitive targeted ultra-high-performance liquid chromatography coupled to high-resolution quadrupole-orbitrap mass spectrometry method (UHPLC-HRMS). The results supported our hypothesis, because nine ecdysteroids were detected in bat blood. The spectrum of these ecdysteroids was similar in those bat species which have their most preferred food items from the same insect order, supporting insects as the most likely source of these hormones. It was also shown that the spectrum of blood-borne ecdysteroids was broader in the autumn than in the summer, and higher concentrations of 20-hydroxyecdysone were measured in samples of large size bat species in comparison with small size ones. Based on the known physiologic effects of ecdysteroids, we postulate that these results might have implications on the metabolic rate and parasite burdens of insectivorous bats.

zoology↗

bioRxiv2020

The heart microbiome of insectivorous bats from Central and South Eastern Europe

Host associated microbiome not only may affect the individual health-status or provide insights into the species- or group specific bacterial communities but may act as early warning signs in the assessment of zoonotic reservoirs, offering clues to predict, prevent and control possible episodes of emerging zoonoses. Bats may be carriers and reservoirs of multiple pathogens such as viruses, bacteria and parasites, showing in the same time robust immunity against many of them. The microbiota plays a fundamental role on the induction, training and function of the host immune system and the immune system has largely evolved in order to maintain the symbiotic relationship of the host with these diverse microbes. Thus, expanding our knowledge on bat-associated microbiome it can be usefully in understanding bats outstanding immune capacities. The aim of this study was to investigate the presence of different bacterial communities in heart tissue of insectivorous bats, Nyctalus noctula, Pipistrellus pipistrellus and Rhinoplophus hipposideros, from Central and Eastern Europe using high-throughput sequencing of variable regions of the 16S rRNA. In addition, species-specific PCRs were used to validate the presence of the vector-borne pathogens Bartonella spp. and Rickettsia spp. In this study we identified a wide variety of bacterial groups, with the most abundant phyla being Proteobacteria and Firmicutes. The results showed that at individual level, the year or location had no effect on the diversity and composition of the microbiome, however host species determined both structure and abundance of the bacterial community. We report the presence of vector-borne bacteria Bartonella spp. in samples of N. noctula and indications of Rickettsia spp. in R. hipposideros. Our results provide a first insight into the bacterial community found in heart tissue of bats from Central and South Eastern Europe.

microbiology↗