Search results for "Intracellular"
showing 10 items of 821 documents
Restoration of Impaired Metabolic Energy Balance (ATP Pool) and Tube Formation Potential of Endothelial Cells under “high glucose”, Diabetic Conditio…
2017
Micro-vascularization is a fast, energy-dependent process that is compromised by elevated glucose concentrations such as in diabetes mellitus disease. Here, we studied the effect of the physiological bioinorganic polymer, polyphosphate (polyP), on the reduced ATP content and impaired function of endothelial cells cultivated under "high glucose" (35 mM diabetes mellitus conditions) concentrations. This high-energy biopolymer has been shown to provide a source of metabolic energy, stored in its phosphoanhydride bonds. We show that exposure of human umbilical vein endothelial cells (HUVEC cells) to "high glucose" levels results in reduced cell viability, increased apoptotic cell death, and a d…
Age and muscle function are more closely associated with intracellular magnesium, as assessed by 31P magnetic resonance spectroscopy, than with serum…
2019
Total serum magnesium is a common clinical measurement for assessing magnesium status; however, magnesium in blood represents less than 1% of the body’s total magnesium content. We measured intramuscular ionized magnesium by phosphorus magnetic resonance spectroscopy (31P-MRS) and tested the hypothesis that this measure better correlates with skeletal muscle function and captures more closely the effect of aging than the traditional measure of total serum magnesium. Data were collected from 441 participants (age 24–98 years) in the Baltimore Longitudinal Study of Aging (BLSA), a study of normative aging that encompasses a broad age range. Results showed that intramuscular ionized magnesium …
The Vitamin D Receptor Regulates Glycerolipid and Phospholipid Metabolism in Human Hepatocytes.
2020
The vitamin D receptor (VDR) must be relevant to liver lipid metabolism because VDR deficient mice are protected from hepatosteatosis. Therefore, our objective was to define the role of VDR on the overall lipid metabolism in human hepatocytes. We developed an adenoviral vector for human VDR and performed transcriptomic and metabolomic analyses of cultured human hepatocytes upon VDR activation by vitamin D (VitD). Twenty percent of the VDR responsive genes were related to lipid metabolism, including MOGAT1, LPGAT1, AGPAT2, and DGAT1 (glycerolipid metabolism)
STRIPAK Members Orchestrate Hippo and Insulin Receptor Signaling to Promote Neural Stem Cell Reactivation
2019
Summary Adult stem cells reactivate from quiescence to maintain tissue homeostasis and in response to injury. How the underlying regulatory signals are integrated is largely unknown. Drosophila neural stem cells (NSCs) also leave quiescence to generate adult neurons and glia, a process that is dependent on Hippo signaling inhibition and activation of the insulin-like receptor (InR)/PI3K/Akt cascade. We performed a transcriptome analysis of individual quiescent and reactivating NSCs harvested directly from Drosophila brains and identified the conserved STRIPAK complex members mob4, cka, and PP2A (microtubule star, mts). We show that PP2A/Mts phosphatase, with its regulatory subunit Widerbors…
Protoparvovirus Knocking at the Nuclear Door
2017
Protoparvoviruses target the nucleus due to their dependence on the cellular reproduction machinery during the replication and expression of their single-stranded DNA genome. In recent years, our understanding of the multistep process of the capsid nuclear import has improved, and led to the discovery of unique viral nuclear entry strategies. Preceded by endosomal transport, endosomal escape and microtubule-mediated movement to the vicinity of the nuclear envelope, the protoparvoviruses interact with the nuclear pore complexes. The capsids are transported actively across the nuclear pore complexes using nuclear import receptors. The nuclear import is sometimes accompanied by structural chan…
More than a pore: How voltage-gated calcium channels act on different levels of neuronal communication regulation.
2021
ABSTRACT Voltage-gated calcium channels (VGCCs) represent key regulators of the calcium influx through the plasma membrane of excitable cells, like neurons. Activated by the depolarization of the membrane, the opening of VGCCs induces very transient and local changes in the intracellular calcium concentration, known as calcium nanodomains, that in turn trigger calcium-dependent signaling cascades and the release of chemical neurotransmitters. Based on their central importance as concierges of excitation-secretion coupling and therefore neuronal communication, VGCCs have been studied in multiple aspects of neuronal function and malfunction. However, studies on molecular interaction partners …
Exosomes as delivery vehicles: a commentary on "Amoxicillin haptenates intracellular proteins that can be transported in exosomes to target cells".
2017
Exosomes are lipoproteic nanosize vesicles of endocytic origin that are released in the extracellular space by several cell types when a multivesicular body fuses with the plasma membrane (1). To date, accumulating evidences highlight the potential of exosomes as messenger in intercellular communication. Indeed, several studies reported the presence of lipids, proteins, metabolites and nucleic acid (DNA, mRNA, microRNA, lncRNA) in exosomes and highlight their functional role in physiological and pathological processes (2).
Mitochondrial CB1 receptors regulate neuronal energy metabolism
2012
The mammalian brain is one of the organs with the highest energy demands, and mitochondria are key determinants of its functions. Here we show that the type-1 cannabinoid receptor (CB(1)) is present at the membranes of mouse neuronal mitochondria (mtCB(1)), where it directly controls cellular respiration and energy production. Through activation of mtCB(1) receptors, exogenous cannabinoids and in situ endocannabinoids decreased cyclic AMP concentration, protein kinase A activity, complex I enzymatic activity and respiration in neuronal mitochondria. In addition, intracellular CB(1) receptors and mitochondrial mechanisms contributed to endocannabinoid-dependent depolarization-induced suppres…
Effect of Combined Physical Stresses on Cells: The Role of Water
2010
International audience; The role of water in microorganism viability was assessed through the application of combined physical perturbations. The combination of different physical parameters could allow to balance the properties variations (especially water related) resulting from the increase of one parameter alone. Thus, it is possible to optimize the survival of cells in controlling these parameters. This was tested through two different examples. The first example shows that combination of osmotic level and temperature can allow optimizing yeast cell survival in following membrane fluidity variation. Moreover this analysis has allowed a better comprehension of cell inactivation during r…
Lewy body extracts from Parkinson disease brains trigger α-synuclein pathology and neurodegeneration in mice and monkeys
2014
Objective Mounting evidence suggests that α-synuclein, a major protein component of Lewy bodies (LB), may be responsible for initiating and spreading the pathological process in Parkinson disease (PD). Supporting this concept, intracerebral inoculation of synthetic recombinant α-synuclein fibrils can trigger α-synuclein pathology in mice. However, it remains uncertain whether the pathogenic effects of recombinant synthetic α-synuclein may apply to PD-linked pathological α-synuclein and occur in species closer to humans. Methods Nigral LB-enriched fractions containing pathological α-synuclein were purified from postmortem PD brains by sucrose gradient fractionation and subsequently inoculate…