Wetenschap en bijgeloof

status: publishe

Das Königinnenenzym

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Kein Wundermittel

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Beekeepers and Scientists, or Beekeepers vs. Scientists?

Ernst UR, Detienne G, Cardoen D. Beekeepers and Scientists, or Beekeepers vs. Scientists? Bee World. 2020;97(3):75-77

Royalactine als verjongingskuur, ook voor de mens?

status: publishe

Long live the Queen - Royalactin extends lifespan of C.elegans through epidermal growth factor (EGF) signaling

Royalactin is a glycoprotein essential for the development of long-lived queen honeybees. Only larvae fed with royal jelly, containing royalactin, develop into queens. Royalactin plays a central role in this process by switching on the epidermal growth factor (EGF) receptor signaling pathway, which ultimately leads to epigenetic changes and a long-lived queen phenotype. Recently it was shown that royalactin also extends lifespan in Drosophila melanogaster. Yet, the mechanism by which royalactin promotes longevity remains largely unknown. We set out to characterize the effects of royalactin on Caenorhabditis elegans lifespan, and clarify the possible involvement of EGF signaling in this process. We demonstrate that royalactin extends lifespan of this nematode by ~30% and that both EGF (LIN-3) and its receptor (LET-23) are essential for royalactin to exert its positive effects. Additionally, we show that royalactin enhances stress tolerance and locomotion in adult nematodes, implying that royalactin also influences healthspan. Our results support the rather novel notion that the EGF pathway, next to its important role in early development, may acts as a regulator of aging in adult animals. In short, we show that royalactin is an important lifespan-extending factor in royal jelly and acts by promoting EGF signaling in C. elegans. Further work is now being carried out to clarify which (secondary) signaling pathways are activated by royalactin, and how this ultimately translates into an extended health- and lifespan.Short oral presentation.status: publishe

Royalactin extends lifespan of C. elegans through EGF signaling

status: publishe

SKN-1-independent transcriptional activation of glutathione S-transferase 4 (GST-4) by EGF signaling

In C. elegans research, transcriptional activation of glutathione S-transferase 4 (gst-4) is often used as a read-out for SKN-1 activity. While many heed an assumed non-exclusivity of the GFP reporter signal driven by the gst-4 promoter to SKN-1, this is also often ignored. We here show that gst-4 can also be transcriptionally activated by EOR-1, a transcription factor mediating effects of the epidermal growth factor (EGF) pathway. Along with enhancing exogenous oxidative stress tolerance, EOR-1 independently of SKN-1 increases gst-4 transcription in response to augmented EGF signaling. Our findings caution researchers within the C. elegans community to always rely on sufficient experimental controls when assaying SKN-1 transcriptional activity with a gst-4p::gfp reporter, such as SKN-1 loss-of-function mutants and/or additional target genes next to gst-4.status: publishe

Functional neuropeptidomics in invertebrates

Neuropeptides are key messengers in almost all physiological processes. They originate from larger precursors and are extensively processed to become bioactive. Neuropeptidomics aims to comprehensively identify the collection of neuropeptides in an organism, organ, tissue or cell. The neuropeptidome of several invertebrates is thoroughly explored since they are important model organisms (and models for human diseases), disease vectors and pest species. The charting of the neuropeptidome is the first step towards understanding peptidergic signaling. This review will first discuss the latest developments in exploring the neuropeptidome. The physiological roles and modes of action of neuropeptides can be explored in two ways, which are largely orthogonal and therefore complementary. The first way consists of inferring the functions of neuropeptides by a forward approach where neuropeptide profiles are compared under different physiological conditions. Second is the reverse approach were neuropeptide collections are used to screen for receptor-binding. This is followed by localization studies and functional tests. This review will focus on how these different functional screening methods contributed to the field of invertebrate neuropeptidomics and expanded our knowledge of peptidergic signaling. This article is part of a Special Issue entitled: Neuroproteomics: Applications in Neuroscience and Neurology.publisher: Elsevier articletitle: Functional neuropeptidomics in invertebrates journaltitle: Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics articlelink: http://dx.doi.org/10.1016/j.bbapap.2014.12.011 content_type: article copyright: Copyright © 2015 Elsevier B.V. All rights reserved.status: publishe

EOR-1 as mediator of life- and health-promoting EGF signaling

Royalactin is a glycoprotein essential for the development of long-lived queen honeybees. We recently provided the first evidence for its longevity-promoting actions in a non-insect species by studying royalactin-fed C. elegans (Detienne et al., Experimental Gerontology 2015). We demonstrated that royalactin requires both Epidermal Growth Factor (EGF, LIN-3) and its receptor (LET-23) for extension of C. elegans lifespan by ~25%. Royalactin also enhanced stress tolerance and locomotion in adult nematodes, suggesting a positive effect on healthspan as well. Yet, the mechanism by which royalactin exerts these EGF-mediated effects remained largely unknown. Our work now reveals that EGF signaling is capable of SKN-1-independent transcriptional activation of glutathione S-transferase 4 (GST-4). For this it relies on the transcription factor EOR-1, which is needed for both the life- and the health-promoting effects of royalactin. While reproductive capacity remains unaltered upon royalactin treatment, additional molecular effectors emerging from differential proteomics analyses suggest that autophagy and/or translation are affected in royalactin-fed animals. These data help clarify the relations between EGF signaling, lifespan, health, stress tolerance, and reproduction in aging C. elegans.status: publishe