Search results for "SECRETION"
showing 10 items of 764 documents
Centrosome amplification mediates small extracellular vesicles secretion via lysosome disruption
2020
SummaryBidirectional communication between cells and their surrounding environment is critical in both normal and pathological settings. Extracellular vesicles (EVs), which facilitate the horizontal transfer of molecules between cells, are recognized as an important constituent of cell-cell communication. In cancer, alterations in EV secretion contribute to the growth and metastasis of tumor cells. However, the mechanisms underlying these changes remain largely unknown. Here, we show that centrosome amplification is associated with and sufficient to promote small extracellular vesicle (SEV) secretion in pancreatic cancer cells. This is a direct result due of lysosomal dysfunction, caused by…
Human POMC processing in vitro and in vivo revealed by quantitative peptidomics
2018
ABSTRACTHuman obesity can result from the aberrant production or processing of proopiomelanocortin (POMC) in hypothalamic neurons, but it is unclear which human POMC-derived peptides are most relevant to body weight regulation. To address this question, we analysed both hypothalamic neurons derived from human pluripotent stem cells (hPSCs) and primary human hypothalamic tissue using quantitative liquid chromatography tandem mass spectroscopy (LC-MS/MS). In both in vitro- and in vivo-derived samples, we found that POMC was processed into β-melanocyte stimulating hormone (β-MSH), whose existence in the human brain has been controversial. β-MSH and desacetyl α-MSH (d-α-MSH) were produced at ro…
1H, 13C, and 15N NMR chemical shift assignment of the complex formed by the first EPEC EspF repeat and N-WASP GTPase binding domain
2021
AbstractLEE-encoded effector EspF (EspF) is an effector protein part of enteropathogenic Escherichia coli’s (EPEC’s) arsenal for intestinal infection. This intrinsically disordered protein contains three highly conserved repeats which together compose over half of the protein’s complete amino acid sequence. EPEC uses EspF to hijack host proteins in order to promote infection. In the attack EspF is translocated, together with other effector proteins, to host cell via type III secretion system. Inside host EspF stimulates actin polymerization by interacting with Neural Wiskott-Aldrich syndrome protein (N-WASP), a regulator in actin polymerization machinery. It is presumed that EspF acts by di…
The Vibrio choleare haemolysin anion channel is required for cell vacuolation and death
2002
SummarySeveral strains of Vibrio cholerae secrete ahaemolytic toxin of 63kDa, termed V. cholerae cytolysin (VCC). This toxin causes extensive vacuo-lation and death of cells in culture and forms ananion-selective channel in planar lipid bilayers and incells. Here, we identify inhibitors of the VCC anionchannel and show that the formation of the anionchannel is necessary for the development of the vacuoles and for the cell death induced by this toxin. Using markers of cell organelles, we show that vacuoles derive from different intracellular com-partments and we identify the contribution of lateendosomes and of the trans -Golgi network in vacuolebiogenesis.Introduction The Gram-negative bact…
Down-regulation of Endogenous Amyloid Precursor Protein Processing due to Cellular Aging
2005
Processing of amyloid precursor protein (APP) is a well acknowledged central pathogenic mechanism in Alzheimer disease. However, influences of age-associated cellular alterations on the biochemistry of APP processing have not been studied in molecular detail so far. Here, we report that processing of endogenous APP is down-regulated during the aging of normal human fibroblasts (IMR-90). The generation of intracellular APP cleavage products C99, C83, and AICD gradually declines with increasing life span and is accompanied by a reduced secretion of soluble APP (sAPP) and sAPPalpha. Further, the maturation of APP was reduced in senescent cells, which has been shown to be directly mediated by a…
Safety and immunomodulatory effects of three probiotic strains isolated from the feces of breast-fed infants in healthy adults: SETOPROB study.
2013
We previously described the isolation and characterization of three probiotic strains from the feces of exclusively breast-fed newborn infants: Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036. These strains were shown to adhere to intestinal mucus in vitro, to be sensitive to antibiotics and to resist biliary salts and low pH. In the present study, a multicenter, randomized, double-blind, placebo-controlled trial with 100 healthy volunteers in three Spanish cities was carried out to evaluate the tolerance, safety, gut colonization and immunomodulatory effects of these three probiotics. Volunteers underwent a 15-day washout perio…
NEW THERAPEUTIC PERSPECTIVES IN IRRITABLE BOWEL SYNDROME: TARGETING LOW-GRADE INFLAMMATION, IMMUNO-NEUROENDOCRINE AXIS, MOTILITY, SDECRETION AND BEYO…
2017
Irritable bowel syndrome (IBS) is a chronic, recurring, and remitting functional disorder of the gastrointestinal tract characterized by abdominal pain, distention, and changes in bowel habits. Although there are several drugs for IBS, effective and approved treatments for one or more of the symptoms for various IBS subtypes are needed. Improved understanding of pathophysiological mechanisms such as the role of impaired bile acid metabolism, neurohormonal regulation, immune, dysfunction, the epithelial barrier and the secretory properties of the gut has led to advancements in the treatment of IBS. With regards to therapies for restoring intestinal permeability, multiple studies with prebiot…
Modulation by Scopolamine, Acetylcholine and Choline of the Evoked Release of Acetylcholine from the Guinea Pig Myenteric Plexus: Evidence for a Musc…
1981
There is evidence that the release of acetylcholine (ACh) from the guinea pig myenteric plexus is controlled via presynaptic muscarine receptors. Muscarinic antagonists such as atropine enhance the release evoked by either electrical field stimulation, by nicotinic drugs or by high K+ concentrations (4,7,10). On the other hand, the muscarinic agonist oxotremorine inhibits the evoked release of ACh (7). A comparable feedback inhibition has been described for the release of ACh from central cholinergic nerves (for review, see Ref. 12). However, it has so far not been shown whether the physiological transmitter itself is able to depress the release of neuronal ACh. We have, therefore, studied …
An in vitro model for the study of human parathyroid gland tissue: Single cell suspensions and monolayer cultures
1982
An in vitro model for studies of parathyroid physiology is described using single cell suspensions and adherent monolayer cultures of human parathyroid tissue. The isolated cells were viable and maintained functional properties tested by calcium and magnesium sensitivity. Parathyroid hormone (PTH) secretion could be suppressed by rising calcium and magnesium concentrations. The secretory behaviour of the cells was not altered by cultivation or cryopreservation. The morphological integrity of the individual cells after mechanical and enzymatic preparation was confirmed by light and electron microscopy.
Maternal Microbiota, Cortisol Concentration, and Post-Partum Weight Recovery Are Dependent on Mode of Delivery
2020
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