Genome wide analysis of gene expression changes in skin from patients with type 2 diabetes

Non-healing chronic ulcers are a serious complication of diabetes and are a major healthcare problem. While a host of treatments have been explored to heal or prevent these ulcers from forming, these treatments have not been found to be consistently effective in clinical trials. An understanding of the changes in gene expression in the skin of diabetic patients may provide insight into the processes and mechanisms that precede the formation of non-healing ulcers. In this study, we investigated genome wide changes in gene expression in skin between patients with type 2 diabetes and non-diabetic patients using next generation sequencing. We compared the gene expression in skin samples taken from 27 patients (13 with type 2 diabetes and 14 non-diabetic). This information may be useful in identifying the causal factors and potential therapeutic targets for the prevention and treatment of diabetic related diseases

Bees Could Visit Flower “Pharmacies” When They Are Sick

peer reviewedWhen you are sick, you might go to the pharmacy to get some medicines. But have you ever wondered what do animals do when they are sick? Bees are tremendously important given the roles they play in the environment and human societies. Unfortunately, bees have been declining in the last decades, partly due to infection by parasites. But certain flowers may help them! Bees collect resources from various flowers and, recently, scientists have shown that some of these flower resources could help bees fight infections. Flower resources contain many essential nutrients as well as very specific medicines that could strengthen the bees or kill the parasites. Once sick, bees could prioritize the collection of resources from specific flowers to dealwith their parasites and heal themselves. It is therefore important for us to plant flowers rich in essential nutrients, as well as flowers rich in medicines that help bees to thrive and fight o infections

Stressful conditions reveal decrease in size, modification of shape but relatively stable asymmetry in bumblebee wings

Human activities can generate a wide variety of direct and indirect effects on animals, which can manifest as environmental and genetic stressors. Several phenotypic markers have been proposed as indicators of these stressful conditions but have displayed contrasting results, depending, among others, on the phenotypic trait measured. Knowing the worldwide decline of multiple bumblebee species, it is important to understand these stressors and link them with the drivers of decline. We assessed the impact of several stressors (i.e. natural toxin-, parasite-, thermic- and inbreeding-stress) on both wing shape and size and their variability as well as their directional and fluctuating asymmetries. The total data set includes 650 individuals of Bombus terrestris (Hymenoptera: Apidae). Overall wing size and shape were affected by all the tested stressors. Except for the sinigrin (e.g. glucosinolate) stress, each stress implies a decrease of wing size. Size variance was affected by several stressors, contrary to shape variance that was affected by none of them. Although wing size directional and fluctuating asymmetries were significantly affected by sinigrin, parasites and high temperatures, neither directional nor fluctuating shape asymmetry was significantly affected by any tested stressor. Parasites and high temperatures led to the strongest phenotype modifications. Overall size and shape were the most sensitive morphological traits, which contrasts with the common view that fluctuating asymmetry is the major phenotypic marker of stress

Behavioral adaptation to polylectism in bees

Sterolic composition of pollen is highly variable among plant species. These compounds are known to be essential for bees as they play important roles in their metabolism such as molting hormone precursors . As they forage on many different plant species, polylectic bees could especially be impacted by this sterolic variability. This work aimed to investigate potential behavioral adaptation of polylectic bees to this variability by adding particular sterols during confection of pollen loads. By contrast, specialist species are expected to be adaptated to their host-plant and would not display such behavior

Do invaders come in peace? Two invasive species as potential food resources for a generalist bumble bee

Invasive plants are often pointed out as a potential driver of bee decline. However, their impact on bee population remains quite unclear and still controversial. Here, we compared (1) the amino acid composition of pollen from three native and two invasive plant species included in diets of Bombus terrestris, (2) the nutritional intake and (3) the pollen foraging behaviour of workers. We found nutritional and behavioural significant differences among the studied plants. Results of this study suggest that common generalist bumble bees might not always suffer from plant invasions, depending on their behavioural plasticity and nutritional requirements

Invasive plants as potential food resource for native pollinators: A case study with two invasive species and a generalist bumble bee

peer reviewedIt is now well established that invasive plants may induce drifts in the quantity and/or quality of floral resources. They are then often pointed out as a potential driver of bee decline. However, their impact on bee population remains quite unclear and still controversial, as bee responses are highly variable among species. Here, we compared the amino acid composition of pollen from three native and two invasive plant species included in diets of common pollinators in NW Europe. Moreover, the nutritional intake (i.e., pollen and amino acid intakes) of Bombus terrestris colonies and the pollen foraging behaviour of workers (i.e., visiting rate, number of foraging trips, weight of pollen loads) were considered. We found significant differences in pollen nutrients among the studied species according to the plant invasive behaviour. We also found significant differences in pollen foraging behaviour according to the plant species, from few to several foraging trips carrying small or large pollen loads. Such behavioural differences directly impacted the pollen intake but depended more likely on plant morphology rather than on plant invasive behaviour. These results suggest that common generalist bumble bees might not always suffer from plant invasions, depending on their behavioural plasticity and nutritional requirements

The impact of pollen quality on the sensitivity of bumblebees to pesticides

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Pollen as Bee Medicine: Is Prevention Better than Cure?

peer reviewedTo face environmental stressors such as infection, animals may display behavioural plasticity to improve their physiological status through ingestion of specific food. In bees, the significance of medicating pollen may be limited by their ability to exploit it. Until now, studies have focused on the medicinal effects of pollen and nectar after forced-feeding experiments, overlooking spontaneous intake. Here, we explored the medicinal effects of different pollen on Bombus terrestris workers infected by the gut parasite Crithidia bombi. First, we used a forced-feeding experimental design allowing for the distinction between prophylactic and therapeutic effects of pollen, considering host tolerance and resistance. Then, we assessed whether bumble bees favoured medicating resources when infected to demonstrate potential self-medicative behaviour. We found that infected bumble bees had a lower fitness but higher resistance when forced to consume sunflower or heather pollen, and that infection dynamics was more gradual in therapeutic treatments. When given the choice between resources, infected workers did not target medicating pollen, nor did they consume more medicating pollen than uninfected ones. These results emphasize that the access to medicating resources could impede parasite dynamics, but that the cost-benefit trade-off could be detrimental when fitness is highly reduced