Search results for "Homeostasis"
showing 10 items of 630 documents
Co-option of Neutrophil Fates by Tissue Environments
2020
Classically considered short-lived and purely defensive leukocytes, neutrophils are unique in their fast and moldable response to stimulation. This plastic behavior may underlie variable and even antagonistic functions during inflammation or cancer, yet the full spectrum of neutrophil properties as they enter healthy tissues remains unexplored. Using a new model to track neutrophil fates, we found short but variable lifetimes across multiple tissues. Through analysis of the receptor, transcriptional, and chromatin accessibility landscapes, we identify varying neutrophil states and assign non-canonical functions, including vascular repair and hematopoietic homeostasis. Accordingly, depletion…
Oral homeostasis disruption by medical plasticizer component bisphenol A in adult male rats.
2013
Objectives/Hypothesis Bisphenol A (BPA) is a synthetic estrogen-like chemical mimetic widely used in the manufacture of polycarbonate plastics and epoxy resins found in numerous consumer products including food packaging, medical devices, and dental sealants. Because it is recovered in fluids and it can reach high levels in saliva, this study aimed to evaluate its safety on oral homeostasis by examining its effects on salivary glands, mouth epithelium, water consumption, and salt preference, each parameter being estrogen sensitive. Study Design Randomized controlled trial involving rats. Methods A dose-response study was conducted in adult Wistar rats randomized into five groups (n = 12). B…
Natriuretic peptide system expression in murine and human submandibular salivary glands: a study of the spatial localisation of ANB, BNP, CNP and the…
2019
AbstractThe natriuretic peptide (NP) system comprises of three ligands, the Atrial Natriuretic Peptide (ANP), Brain Natriuretic peptide (BNP) and C-type Natriuretic peptide (CNP), and three natriuretic peptide receptors, NPRA, NPRB and NPRC. Here we present a comprehensive study of the natriuretic peptide system in healthy murine and human submandibular salivary glands (SMGs). We show CNP is the dominant NP in mouse and human SMG and is expressed together with NP receptors in ducts, autonomic nerves and the microvasculature of the gland, suggesting CNP autocrine signalling may take place in some of these glandular structures. These data suggest the NP system may control salivary gland funct…
Functional characterization of the dural sinuses as a neuroimmune interface
2021
Summary Despite the established dogma of central nervous system (CNS) immune privilege, neuroimmune interactions play an active role in diverse neurological disorders. However, the precise mechanisms underlying CNS immune surveillance remain elusive; particularly, the anatomical sites where peripheral adaptive immunity can sample CNS-derived antigens and the cellular and molecular mediators orchestrating this surveillance. Here, we demonstrate that CNS-derived antigens in the cerebrospinal fluid (CSF) accumulate around the dural sinuses, are captured by local antigen-presenting cells, and are presented to patrolling T cells. This surveillance is enabled by endothelial and mural cells formin…
Glucose-induced alterations of cytosolic free calcium in cultured rat tail artery vascular smooth muscle cells
1995
We have previously suggested that hyperglycemia per se may contribute to diabetic hypertensive and vascular disease by altering cellular ion content. To more directly investigate the potential role of glucose in this process, we measured cytosolic free calcium in primary cultures of vascular smooth muscle cells isolated from Sprague-Dawley rat tail artery before and after incubation with 5 (basal), 10, 15, and 20 mM glucose. Glucose significantly elevated cytosolic free calcium in a dose- and time-dependent manner, from 110.0 +/- 5.4 to 124.5 +/- 9.0, 192.7 +/- 20.4, and 228.4 +/- 21.9 nM at 5, 10, 15, and 20 mM glucose concentrations, respectively. This glucose-induced cytosolic free calci…
A mouse model of in vivo chemical inhibition of retinal calcium-independent phospholipase A2 (iPLA2).
2013
International audience; Numerous studies have reported the implication of calcium-independent phospholipase A2 (iPLA2) in various biological mechanisms. Most of these works have used in vitro models and only a few have been carried out in vivo on iPLA2(-/-) mice. The functions of iPLA2 have been investigated in vivo in the heart, brain, pancreatic islets, and liver, but not in the retina despite its very high content in phospholipids. Phospholipids in the retina are known to be involved in several various key mechanisms such as visual transduction, inflammation or apoptosis. In order to investigate the implication of iPLA2 in these processes, this work was aimed to build an in vivo model of…
2-Methoxyestradiol confers neuroprotection and inhibits a maladaptive HIF-1α response after traumatic brain injury in mice
2014
HIF-1α is pivotal for cellular homeostasis in response to cerebral ischemia. Pharmacological inhibition of HIF-1α may reduce secondary brain damage by targeting post-translational mechanisms associated with its proteasomal degradation and nuclear translocation. This study examined the neuroprotective effects of 2-methoxyestradiol (2ME2), the involved HIF-1α-dependent response, and alternative splicing in exon 14 of HIF-1α (HIF-1α∆Ex14) after traumatic brain injury (TBI) in mice. Intraperitoneal 2ME2 administration 30 min after TBI caused a dose-dependent reduction in secondary brain damage after 24 h. 2ME2 was physiologically tolerated, showed no effects on immune cell brain migration, and …
TRIB1 constitutes a molecular link between regulation of sleep and lipid metabolism in humans.
2012
Epidemiological studies show association between sleep duration and lipid metabolism. In addition, inactivation of circadian genes induces insulin resistance and hyperlipidemia. We hypothesized that sleep length and lipid metabolism are partially controlled by the same genes. We studied the association of total sleep time (TST) with 60 genetic variants that had previously been associated with lipids. The analyses were performed in a Finnish population-based sample (N = 6334) and replicated in 2189 twins. Finally, RNA expression from mononuclear leucocytes was measured in 10 healthy volunteers before and after sleep restriction. The genetic analysis identified two variants near TRIB1 gene th…
Cerebral haemodynamic changes during propofol-remifentanil or sevoflurane anaesthesia: transcranial Doppler study under bispectral index monitoring
2006
Background. Sevoflurane or propofol–remifentanil-based anaesthetic regimens represent modern techniques for neurosurgical anaesthesia. Nevertheless, there are potential differences related to their activity on the cerebrovascular system. The magnitude of such difference is not completely known. Methods. In total 40 patients, treated for spinal or maxillo-facial disorders, were randomly allocated to either i.v. propofol–remifentanil or inhalational sevoflurane anaesthesia. Transcranial Doppler was used to assess changes in cerebral blood flow velocity, carbon dioxide reactivity, cerebral autoregulation and the bispectral index to assess the depth of anaesthesia. Results. Time-averaged mean f…
Presence of Oxytocin, Vasopressin and Atrial Natriuretic Peptide and Their Modification in Rat Hypothalamic Paraventricular Nucleus During Resistance…
2013
Summary Many studies have demonstrated the physiological effects of oxytocin (OT), atrial natriuretic peptide (ANP) and vasopressin (VP) in the homoeostasis of body fluids during physical exercise. However, a little information is available about the related immunohistochemical changes in hypothalamic magnocellular neurosecretory system during and after the training. The aim of the present work was to study the immunohistochemical changes in OT, ANP and VP levels in the hypothalamic paraventricular nucleus during and after resistance exercise protocol. Three groups of Wistar rats were trained by a rung ladder protocol for 15, 30 and 45 days, respectively; a fourth group was left to rest for…