Down-Regulation of Honey Bee IRS Gene Biases Behavior toward Food Rich in Protein

Food choice and eating behavior affect health and longevity. Large-scale research efforts aim to understand the molecular and social/behavioral mechanisms of energy homeostasis, body weight, and food intake. Honey bees (Apis mellifera) could provide a model for these studies since individuals vary in food-related behavior and social factors can be controlled. Here, we examine a potential role of peripheral insulin receptor substrate (IRS) expression in honey bee foraging behavior. IRS is central to cellular nutrient sensing through transduction of insulin/insulin-like signals (IIS). By reducing peripheral IRS gene expression and IRS protein amount with the use of RNA interference (RNAi), we demonstrate that IRS influences foraging choice in two standard strains selected for different food-hoarding behavior. Compared with controls, IRS knockdowns bias their foraging effort toward protein (pollen) rather than toward carbohydrate (nectar) sources. Through control experiments, we establish that IRS does not influence the bees' sucrose sensory response, a modality that is generally associated with food-related behavior and specifically correlated with the foraging preference of honey bees. These results reveal a new affector pathway of honey bee social foraging, and suggest that IRS expressed in peripheral tissue can modulate an insect's foraging choice between protein and carbohydrate sources

The Worker Honeybee Fat Body Proteome Is Extensively Remodeled Preceding a Major Life-History Transition

Honeybee workers are essentially sterile female helpers that make up the majority of individuals in a colony. Workers display a marked change in physiology when they transition from in-nest tasks to foraging. Recent technological advances have made it possible to unravel the metabolic modifications associated with this transition. Previous studies have revealed extensive remodeling of brain, thorax, and hypopharyngeal gland biochemistry. However, data on changes in the abdomen is scarce. To narrow this gap we investigated the proteomic composition of abdominal tissue in the days typically preceding the onset of foraging in honeybee workers

Anti-VEGF treatment patterns and associated health care costs in Switzerland: findings using real-world claims data

Oliver Reich,1 Lucas M Bachmann,2 Livia Faes,3 Sophie C Böhni,3 Mario Bittner,3 Jeremy P Howell,3 Michael A Thiel,3 Roland Rapold,1 Martin K Schmid3 1Department of Health Sciences, Helsana Group, Dübendorf, 2Medignition Inc, Research Consultants, Zurich, 3Eye Clinic, Cantonal Hospital of Lucerne, Lucerne, Switzerland Background: Little is known about the patterns of actual health care delivery of anti-vascular endothelial growth factor (VEGF) treatment in patients with age-related macular degeneration, diabetic retinopathy, and retinal vein occlusion in Switzerland. The purpose of this study was to describe these treatment patterns, specifically comparing the numbers of anti-VEGF injections and associated expenditures between patients treated with ranibizumab and those treated with aflibercept in Switzerland using claims data. Methods: We identified our study patients retrospectively using the Helsana claims database, which includes data on approximately 1.2 million subjects with basic health insurance. Patients qualified for inclusion if ranibizumab or aflibercept had been initiated between December 1, 2012 (when aflibercept was approved by the Federal Office of Public Health) and November 30, 2013. Within this set, patients with at least 12 months of continuous insurance enrolment in the previous year were considered. In univariate analyses, we examined the distribution of demographic data and patient characteristics between those receiving ranibizumab and those receiving aflibercept. Numbers of injections and associated health care expenditures observed during the 6-month follow-up period after incident treatment were the two outcomes considered. In multivariate regression analyses, controlling for possible confounding factors, we compared differences in these two outcomes between patients treated with ranibizumab and those treated with aflibercept. Results: Of 3,260 patients who were on anti-VEGF treatment for an ophthalmological indication between December 1, 2012 and November 30, 2013, 1,150 qualified for inclusion. Age, geographic region, and number of physician visits in the previous year were significant factors in the number of injections given during the 6-month follow-up period. Frequency of injections and associated health care expenditures were similar between the groups when correcting for differences in patient characteristics. Conclusion: Contrary to the recommendations regarding frequency of injections and the results of clinical studies, aflibercept and ranibizumab are used in a similar fashion in Switzerland, resulting in similar total health care expenditures for both these anti-VEGF agents. Keywords: ranibizumab, aflibercept, health care costs, Switzerlan

Host genetic determinants of microbiota-dependent nutrition revealed by genome-wide analysis of Drosophila melanogaster

Animals bear communities of gut microorganisms with substantial effects on animal nutrition, but the host genetic basis of these effects is unknown. Here, we use Drosophila to demonstrate substantial among-genotype variation in the effects of eliminating the gut microbiota on five host nutritional indices (weight, and protein, lipid, glucose and glycogen contents); this includes variation in both the magnitude and direction of microbiota-dependent effects. Genome-wide associations to identify the genetic basis of the microbiota-dependent variation reveal polymorphisms in largely non-overlapping sets of genes associated with variation in the nutritional traits, including strong representation of conserved genes functioning in signaling. Key genes identified by the GWA study are validated by loss-of-function mutations that altered microbiota-dependent nutritional effects. We conclude that the microbiota interacts with the animal at multiple points in the signaling and regulatory networks that determine animal nutrition. These interactions with the microbiota are likely conserved across animals, including humans

Clinical pharmacology of intravitreal anti-VEGF drugs

Clinical efficacy of intravitreal anti-VEGF drugs has been widely demonstrated in several angiogenesis-driven eye diseases including diabetic macular edema and the neovascular form of age-related macular degeneration. Pegaptanib, ranibizumab, and aflibercept have been approved for use in the eye, whereas bevacizumab is widely used by ophthalmologists to treat patients "off-label". These drugs are active in the nanomolar to picomolar range; however, caution is required when establishing the rank order of affinity and potency due to in vitro inter-experimental variation. Despite the small doses used for eye diseases and the intravitreal route of administration may limit systemic side effects, these drugs can penetrate into blood circulation and alter systemic VEGF with unknown clinical consequences, particularly in vulnerable groups of patients. Clinical pharmacokinetics of ocular anti-VEGF agents should therefore be taken into account when choosing the right drug for the individual patient. The gaps in current understanding that leave open important questions are as follows: (i) uncertainty about which drug should be given first, (ii) how long these drugs can be used safely, and (iii) the choice of the best pharmacological strategy after first-line treatment failure. The current review article, based on the information published in peer-reviewed published papers relevant to anti-VEGF treatments and available on the PubMed database, describes in detail the clinical pharmacology of this class of drugs to provide a sound pharmacological basis for their proper use in ophthalmology clinical practice