bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2021.01.05.425375

Sugar feeding enhances gut immunity and protects against arboviral infection in the mosquito vector Aedes aegypti

Almire, F.·Terry, S.·McFarlane, M.·Szemiel, A.·Terhzaz, S.·Varjak, M.·McDonald, A.·Kohl, A.·Pondeville, E.
View original source ↗Export metadata ↓

Abstract

As mosquito females require a blood meal to reproduce, they can act as vectors of numerous pathogens, such as arboviruses (e.g. Zika, dengue and chikungunya viruses), which constitute a substantial worldwide public health burden. In addition to blood meals, mosquito females can also take sugar meals to get carbohydrates for their energy reserves. It is now recognised that diet is a key regulator of health and disease outcome through interactions with the immune system. However, it has been mostly studied in humans and model organisms. So far, the impact of sugar feeding on mosquito immunity and in turn, how this could affect vector competence for arboviruses has not been analysed. Here, we show that sugar feeding increases and maintains antiviral immunity in the digestive tract of the main arbovirus vector Aedes aegypti. Our data demonstrate that the gut microbiota does not mediate the sugar-induced immunity but partly inhibits it. Importantly, sugar intake prior to an arbovirus-infected blood meal further protects females against infection with arboviruses from different families, highlighting a broad antiviral action of sugar. Sugar feeding blocks arbovirus initial infection and dissemination from the gut, lowers infection prevalence and intensity, thereby decreasing transmission potential of female mosquitoes. Overall, our findings uncover a crucial role of sugar feeding in mosquito antiviral immunity and vector competence for arboviruses. Since Ae. aegypti almost exclusively feed on blood in some natural settings, our findings suggest that this could increase the spread of mosquito-borne arboviral diseases.

Source connections

Explore related subjects

physiologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Almire, F., Terry, S., McFarlane, M., Szemiel, A., Terhzaz, S., Varjak, M., McDonald, A., Kohl, A., Pondeville, E.. 2021-01-06. Sugar feeding enhances gut immunity and protects against arboviral infection in the mosquito vector Aedes aegypti. https://doi.org/10.1101/2021.01.05.425375

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Epigenetic Rescue of Disuse Muscle Atrophy by Histone Deacetylase Inhibitor Trichostatin A

Mechanical unloading rapidly induces skeletal muscle atrophy and functional deterioration, yet how the loss of mechanical input influences nuclear architecture, chromatin organization, and associated transcriptional programs remains poorly understood. Here, we investigated whether pharmacological inhibition of histone deacetylases (HDACs) using Trichostatin A (TSA) could attenuate the consequences of continued mechanical unloading in a murine hindlimb suspension model. Following 14 days of unloading, mice exhibited impaired locomotor activity, altered muscle architecture, and widespread transcriptional reprogramming characterized by increased expression of atrophy associated genes, inflammatory mediators, and extracellular matrix remodeling pathways, alongside suppression of mitochondrial metabolic programs. Super resolution imaging further revealed irregular Lamin A/C organization and disruption of discrete H3K9me3 associated heterochromatin foci. Systemic TSA treatment significantly attenuated the decline in locomotor activity, accompanied by trends toward reduced body weight loss, and preservation of muscle morphology. Transcriptomic analysis demonstrated a substantial shift toward the baseline expression profile, with high-dose TSA attenuating FOXO associated catabolic programs, inflammatory, and extracellular matrix-related signatures, while enhancing mitochondrial oxidative phosphorylation pathways. Quantitative gene level and pathway analyses further revealed dose dependent and selective reversal of unloading associated transcriptional changes. Notably, TSA treatment also partially preserved nuclear lamina organization and the focal distribution of H3K9me3 associated heterochromatin. Despite these muscle specific benefits, TSA did not prevent trabecular bone loss over the 14-day unloading period, although several muscle-expressed genes potentially involved in muscle to bone communication were altered by treatment. Together, these findings demonstrate that HDAC inhibition counteracts multiple functional and molecular consequences of skeletal muscle unloading and is associated with partial preservation of nuclear and heterochromatin organization. This study supports a link between mechanical unloading, nuclear architectural remodeling, and HDAC sensitive transcriptional regulation, providing a foundation for epigenetic strategies to counter disuse induced muscle deterioration.

physiology↗
bioRxiv2026

Residual Hearing Loss After Chronic Cochlear Implantation in Guinea Pigs is Primarily Conductive

It is desirous to preserve residual low-frequency hearing in cochlear implant recipients, as dual stimulation using electrical and acoustic signals results in superior speech-in-noise processing and musicality. However, cochlear implant recipients commonly lose their residual acoustic hearing gradually following surgical placement of the array. The governing mechanism is not understood and is likely due to multiple factors including surgical trauma, inflammation, and the foreign body induced immune response to the array, including formation of intracochlear fibrosis. Normal mechanical function of the cochlea is expected to underpin residual hearing but has not been directly studied. This function includes efficient transmission of sound to the cochlea via the middle ear, sound propagation via the basilar membrane travelling wave, mechanical tuning characteristics, and the non-linear cochlear amplification of responses to low-frequency stimulation. Here, we examined these features in cochleae and middle ears of unimplanted, acutely and chronically implanted guinea pigs using our minimally invasive preparation and optical coherence tomography vibrometry. We observed that mechanical tuning and amplification is not significantly altered by either acute or chronic implant. However, the response threshold was raised and proportional to middle ear responses. Additionally, the organ of Corti phase, and its sound intensity dependent changes, are unaltered by CI. Finally, a cluster analysis revealed sensitivity loss in chronically implanted animals is caused by middle ear dysfunction. Hence, in the guinea pig model, the dominant etiology of residual hearing loss is conductive. More research is required to establish whether residual hearing loss in humans similarly shares conductive elements.

physiology↗
bioRxiv2026

Satellite cell glucocorticoid receptor restrains myogenic commitment without mediating the effects of therapeutic glucocorticoids on muscle repair

Glucocorticoids (GCs) exert profound effects on skeletal muscle, but the contribution of satellite cell (SatC) glucocorticoid receptor (GR) signaling to muscle regeneration remains poorly understood. Here, we investigated the role of GR in SatC homeostasis and assessed whether SatC GR mediates the effects of therapeutic GCs on muscle repair. Conditional deletion of GR in SatC reduced the number of PAX7-positive cells during regeneration in young mice, but did not substantially impair muscle repair in either young or aged animals. Transcriptomic and chromatin profiling revealed that GR occupies genes involved in stem cell fate and developmental signaling, with extensive GR binding already established in quiescent SatC. GR-deficient quiescent SatC showed reduced expression of Yap1, Runx1 and Foxo1, together with increased Myog expression. Similarly, GR silencing in human myoblasts induced early myogenic differentiation markers without affecting proliferation, supporting a conserved role for GR in restraining myogenic commitment. We next examined the effects of two therapeutic GCs on muscle regeneration. Chronic prednisone treatment altered the transcriptional landscape of regenerating muscle in an age-dependent manner, without substantially affecting histological repair. In contrast, dexamethasone administration during the early inflammatory phase delayed regeneration, with persistent necrosis and increased collagen deposition. These effects were comparable in control and SatC-specific GR-deficient mice, indicating that they do not require GR in SatC. Together, these findings identify GR as a regulator of the quiescent, undifferentiated state of SatC, while showing that the effects of therapeutic GCs on muscle repair are largely independent of SatC GR. They further highlight the importance of treatment regimen and physiological context in determining the effects of GCs on skeletal muscle regeneration.

physiology↗