Search results for "Cellula"
showing 10 items of 6516 documents
Adult rat myelin enhances axonal outgrowth from neural stem cells.
2018
Axon regeneration after spinal cord injury (SCI) is attenuated by growth inhibitory molecules associated with myelin. We report that rat myelin stimulated the growth of axons emerging from rat neural progenitor cells (NPCs) transplanted into sites of SCI in adult rat recipients. When plated on a myelin substrate, neurite outgrowth from rat NPCs and from human induced pluripotent stem cell (iPSC)-derived neural stem cells (NSCs) was enhanced threefold. In vivo, rat NPCs and human iPSC-derived NSCs extended greater numbers of axons through adult central nervous system white matter than through gray matter and preferentially associated with rat host myelin. Mechanistic investigations excluded …
Targeting Nitric Oxide with Natural Derived Compounds as a Therapeutic Strategy in Vascular Diseases
2016
Within the family of endogenous gasotransmitters, nitric oxide (NO) is the smallest gaseous intercellular messenger involved in the modulation of several processes, such as blood flow and platelet aggregation control, essential to maintain vascular homeostasis. NO is produced by nitric oxide synthases (NOS) and its effects are mediated by cGMP-dependent or cGMP-independent mechanisms. Growing evidence suggests a crosstalk between the NO signaling and the occurrence of oxidative stress in the onset and progression of vascular diseases, such as hypertension, heart failure, ischemia, and stroke. For these reasons, NO is considered as an emerging molecular target for developing therapeutic stra…
Acute telomerase components depletion triggers oxidative stress as an early event previous to telomeric shortening
2018
Loss of function of dyskerin (DKC1), NOP10 and TIN2 are responsible for different inheritance patterns of Dyskeratosis congenita (DC; ORPHA1775). They are key components of telomerase (DKC1 and NOP10) and shelterin (TIN2), and play an important role in telomere homeostasis. They participate in several fundamental cellular processes by contributing to Dyskeratosis congenita through mechanisms that are not fully understood. Presence of oxidative stress was postulated to result from telomerase ablation. However, the resulting disturbed redox status can promote telomere attrition by generating a vicious circle, which promotes cellular senescence. This fact prompted us to study if acute loss of …
Endothelial progenitor cells in ageing
2016
“The senescence status of somatic stem/progenitor cells contributes to ageing process”, and “an individual is as old as old are its stem cells”. These quotes represent the concepts, which are actually object of investigations of researchers involved in ageing studies.
Longevity: Lesson from model organisms
2019
Research on longevity and healthy aging promises to increase our lifespan and decrease the burden of degenerative diseases with important social and economic effects. Many aging theories have been proposed, and important aging pathways have been discovered. Model organisms have had a crucial role in this process because of their short lifespan, cheap maintenance, and manipulation possibilities. Yeasts, worms, fruit flies, or mammalian models such as mice, monkeys, and recently, dogs, have helped shed light on aging processes. Genes and molecular mechanisms that were found to be critical in simple eukaryotic cells and species have been confirmed in humans mainly by the functional analysis of…
Autophagy during ageing – from Dr Jekyll to Mr Hyde
2017
Autophagy is a ubiquitous catabolic process, which causes cellular bulk degradation through vesicular engulfment of obsolete, damaged or harmful cytoplasmic components. While autophagy regulates cellular homeostasis during development and in youth, there is mounting evidence that autophagy becomes increasingly dysfunctional with age. Recent work in Caenorhabditis elegans even suggests that late-life dysfunctional autophagy exhibits detrimental effects that drive the ageing process. Other studies link elevated autophagy closely to increased health and longevity. This review aims to put these apparently opposing views into perspective and define our current understanding of the role of autoph…
Peripapillary fluorescence lifetime reveals age-dependent changes using fluorescence lifetime imaging ophthalmoscopy in rats
2017
Abstract Many fundus diseases accompany fundus autofluorescence change. Fluorescence lifetime imaging ophthalmoscope (FLIO) is a latest technique in imaging fundus autofluorescence. With FLIO, the fundus fluorescence lifetime (FLT) is recorded topographically, assisting to diagnose and monitor multiple fundus diseases. The purpose of this study was to evaluate the repeatability of FLT using FLIO on adult rats and to analyze the age-dependency of the peripapillary FLT of the fundus in a short spectral channel (498–560 nm) and a long spectral channel (560–720 nm). Sprague Dawley rats (n of eyes = 10) were used for repeatability experiments. Age-dependent changes were investigated in young (tw…
Sodium functions as a negative allosteric modulator of the oxytocin receptor
2017
Abstract The oxytocin receptor, a class A G protein coupled receptor (GPCR), is essentially involved in the physiology of reproduction. Two parameters are crucially important to support high-affinity agonist binding of the receptor: Mg2+ and cholesterol, both acting as positive modulators. Using displacement assays with a high-affinity fluorescent antagonist (OTAN-A647), we now show that sodium functions as a negative allosteric modulator of the oxytocin receptor. In membranes from HEK293 cells stably expressing the oxytocin receptor, oxytocin binding occurred with about 15-fold lower affinity when sodium chloride was increased from 0 to 300 mM, whereas antagonist binding remained largely u…
Desensitization of cAMP Accumulation via Human β3-Adrenoceptors Expressed in Human Embryonic Kidney Cells by Full, Partial, and Biased Agonists
2019
β3-Adrenoceptors couple not only to cAMP formation but, at least in some cell types, also to alternative signaling pathways such as phosphorylation of extracellular signal-regulated kinase (ERK). β3-Adrenoceptor agonists are used in long-term symptomatic treatment of the overactive bladder syndrome; it is only poorly understood which signaling pathway mediates the clinical response and whether it undergoes agonist-induced desensitization. Therefore, we used human embryonic kidney cells stably transfected with human β3-adrenoceptors to compare coupling of ligands with various degrees of efficacy, including biased agonists, to cAMP formation and ERK phosphorylation, particularly regarding des…
Subchronic vortioxetine treatment -but not escitalopram- enhances pyramidal neuron activity in the rat prefrontal cortex.
2017
Abstract Vortioxetine (VOR) is a multimodal antidepressant drug. VOR is a 5-HT 3 -R, 5-HT 7 -R and 5-HT 1D -R antagonist, 5-HT 1B -R partial agonist, 5-HT 1A -R agonist, and serotonin transporter (SERT) inhibitor. VOR shows pro-cognitive activity in animal models and beneficial effects on cognitive dysfunction in major depressive patients. Here we compared the effects of 14-day treatments with VOR and escitalopram (ESC, selective serotonin reuptake inhibitor) on neuronal activity in the medial prefrontal cortex (mPFC). Ten groups of rats (5 standard, 5 depleted of 5-HT with p -chlorophenylalanine -pCPA-, used as model of cognitive impairment) were fed with control food or with two doses of …