Search results for "Proteins"
showing 10 items of 10069 documents
Indicaxanthin from Opuntia ficus indica (L. Mill) Inhibits Oxidized LDL-Mediated Human Endothelial Cell Dysfunction through Inhibition of NF-κB Activ…
2019
Oxidized low-density lipoproteins (oxLDL) play a pivotal role in the etiopathogenesis of atherosclerosis through the activation of inflammatory signaling events eventually leading to endothelial dysfunction and senescence. In the present work, we investigated the effects of indicaxanthin, a bioavailable, redox-modulating phytochemical from Opuntia ficus indica fruits, with anti-inflammatory activity, against oxLDL-induced endothelial dysfunction. Human umbilical vein cord cells (HUVEC) were stimulated with human oxLDL, and the effects of indicaxanthin were evaluated in a range between 5 and 20 μM, consistent with its plasma level after a fruit meal (7 μM). Pretreatment with indicaxanthin si…
Neuronal inhibition of the autophagy nucleation complex extends life span in post-reproductive C. elegans
2017
Autophagy is a ubiquitous catabolic process that causes cellular bulk degradation of cytoplasmic components and is generally associated with positive effects on health and longevity. Inactivation of autophagy has been linked with detrimental effects on cells and organisms. The antagonistic pleiotropy theory postulates that some fitness-promoting genes during youth are harmful during aging. On this basis, we examined genes mediating post-reproductive longevity using an RNAi screen. From this screen, we identified 30 novel regulators of post-reproductive longevity, including pha-4. Through downstream analysis of pha-4, we identified that the inactivation of genes governing the early stages of…
Drosophila Full-Length Amyloid Precursor Protein is Required for Visual Working Memory and Prevents Age-Related Memory Impairment
2018
Summary The β-amyloid precursor protein (APP) plays a central role in the etiology of Alzheimer's disease (AD). However, its normal physiological functions are still unclear. APP is cleaved by various secretases whereby sequential processing by the β- and γ-secretases produces the β-amyloid peptide that is accumulating in plaques that typify AD. In addition, this produces secreted N-terminal sAPPβ fragments and the APP intracellular domain (AICD). Alternative cleavage by α-secretase results in slightly longer secreted sAPPα fragments and the identical AICD. Whereas the AICD has been connected with transcriptional regulation, sAPPα fragments have been suggested to have a neurotrophic and neu…
“Pro-youthful” factors in the “labyrinth” of cardiac rejuvenation
2016
IF 3.350; International audience; The mechanisms of aging and senescence include various endogenous and exogenous factors. Among cardiovascular diseases, heart failure is a typical age-related disease. New strategies to restore cardiomyocyte cells have been reported: endogenous substances that can regenerate the heart's cardiomyocytes have been described: follistatin like 1 (FSTL1), growth-differentiation factor 11 (GDF11) and insulin-like growth factor 1 (IGF-I). Manipulation of the different anti and pro-pathways is essential to discover new approaches to regenerative therapies. (C) 2016 Elsevier Inc. All rights reserved.
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 …
Characterization of NO-Induced Nitrosative Status in Human Placenta from Pregnant Women with Gestational Diabetes Mellitus
2017
Dysregulation of NO production is implicated in pregnancy-related diseases, including gestational diabetes mellitus (GDM). The role of NO and its placental targets in GDM pregnancies has yet to be determined. S-Nitrosylation is the NO-derived posttranslational protein modification that can modulate biological functions by forming NO-derived complexes with longer half-life, termed S-nitrosothiol (SNO). Our aim was to examine the presence of endogenous S-nitrosylated proteins in cysteine residues in relation to antioxidant defense, apoptosis, and cellular signal transduction in placental tissue from control (n=8) and GDM (n=8) pregnancies. S-Nitrosylation was measured using the biotin-switch …
Effects of intrinsic aerobic capacity, aging and voluntary running on skeletal muscle sirtuins and heat shock proteins
2016
Aim Sirtuins are proteins that connect energy metabolism, oxidative stress and aging. Expression of heat shock proteins (Hsps) is regulated by heat shock factors (HSFs) in response to various environmental and physiological stresses, such as oxidative stress. Oxidative stress accumulates during aging which makes cells more prone to DNA damage. Although many experimental animal models have been designed to study the effects of knockdown or overexpression of sirtuins, HSFs and Hsps, little is known about how aging per se affects their expression. Here we study the impact of intrinsic aerobic capacity, aging and voluntary exercise on the levels of sirtuins, HSFs and Hsps in skeletal muscle. Me…
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…
Heat shock protein (Hsp) regulation by muscarinic acetylcholine receptor (mAChR) activation in the rat hippocampus.
2018
The cholinergic system plays a crucial role in modulating in the central nervous system physiological responses such as neurogenesis, neuronal differentiation, synaptic plasticity, and neuroprotection. In a recent study, we showed that Oxotremorine-M, a non-selective muscarinic acetylcholine receptor agonist, is able to transactivate the fibroblast growth factor receptor and to produce a significant increase in the hippocampal primary neurite outgrowth. In the present study we aimed to explore in the rat hippocampus the possible effect of acute or chronic treatment with Oxotremorine-M on some heat shock proteins (Hsp60, Hsp70, Hsp90) and on activation of related transcription factor heat sh…
The endocannabinoid-alcohol crosstalk: Recent advances on a bi-faceted target
2018
Increasing evidence has focusesed on the endocannabinoid system as a relevant player in the induction of aberrant synaptic plasticity and related addictive phenotype following chronic excessive alcohol drinking. In addition, the endocannabinoid system is implicated in the pathogenesis of alcoholic liver disease. Interestingly, whereas the involvement of CB1 receptors in alcohol rewarding properties is established, the central and peripheral action of CB2 signalling is still to be elucidated. This review aims at giving the input to deepen knowledge on the role of the endocannabinoid system, highlighting the advancing evidence that suggests that CB1 and CB2 receptors may play opposite roles i…