Publications by authors named "F Sauve"
Article Synopsis
- The arcuate nucleus (ARH) in the hypothalamus is crucial for energy balance, as it detects metabolic hormones in the blood, but only a few neurons in this area can sense these signals due to a barrier involving the median eminence (ME).
- The study found that the proteoglycan aggrecan, produced by certain ARH neurons, establishes a diffusion gradient that limits the entry of these metabolic signals into the ARH, particularly during fasting when more aggrecan is deposited.
- Disrupting aggrecan deposits allows more blood-borne molecules to enter the ARH, leading to uncontrolled food intake, highlighting the importance of this diffusion barrier in the brain's metabolism regulation.
Background: Estrogen secretion by the ovaries regulates the hypothalamic-pituitary-gonadal axis during the reproductive cycle, influencing gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion, and also plays a role in regulating metabolism. Here, we establish that hypothalamic tanycytes-specialized glia lining the floor and walls of the third ventricle-integrate estrogenic feedback signals from the gonads and couple reproduction with metabolism by relaying this information to orexigenic neuropeptide Y (NPY) neurons.
Methods: Using mouse models, including mice floxed for Esr1 (encoding estrogen receptor alpha, ERα) and those with Cre-dependent expression of designer receptors exclusively activated by designer drugs (DREADDs), along with viral-mediated, pharmacological and indirect calorimetric approaches, we evaluated the role of tanycytes and tanycytic estrogen signaling in pulsatile LH secretion, cFos expression in NPY neurons, estrous cyclicity, body-weight changes and metabolic parameters in adult females.
The pathogenesis of anal sacculitis has not been extensively investigated, although atopic dogs seem to be predisposed to the disease. The aim of this study was therefore to characterize and compare the bacterial microbiota and pro-inflammatory cytokines in the anal sacs of dogs from three groups (healthy dogs, untreated atopic dogs and atopic dogs receiving antipruritic treatment or allergen-specific immunotherapy) in order to determine whether changes could be at the origin of anal sacculitis in atopic dogs. Bacterial populations of anal sac secretions from fifteen healthy dogs, fourteen untreated and six treated atopic dogs were characterized by sequencing the V4 region of the 16S rRNA gene using Illumina technology.
View Article and Find Full Text PDFAlzheimer disease has a sex bias, with women twice as likely as men to be affected. Studies have linked elevated follicle-stimulating hormone (FSH) levels to worsened Alzheimer disease pathology and cognitive decline in mice. FSH interacts with APOE4, uncovering new aspects of Alzheimer disease.
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