Search results for "SIG"
showing 10 items of 19670 documents
Direct Sensing of Nutrients via a LAT1-like Transporter in Drosophila Insulin-Producing Cells
2016
Summary Dietary leucine has been suspected to play an important role in insulin release, a hormone that controls satiety and metabolism. The mechanism by which insulin-producing cells (IPCs) sense leucine and regulate insulin secretion is still poorly understood. In Drosophila, insulin-like peptides (DILP2 and DILP5) are produced by brain IPCs and are released in the hemolymph after leucine ingestion. Using Ca2+-imaging and ex vivo cultured larval brains, we demonstrate that IPCs can directly sense extracellular leucine levels via minidiscs (MND), a leucine transporter. MND knockdown in IPCs abolished leucine-dependent changes, including loss of DILP2 and DILP5 in IPC bodies, consistent wit…
Cellular and Molecular Heterogeneity Associated with Vessel Formation Processes
2018
The microvasculature heterogeneity is a complex subject in vascular biology. The difficulty of building a dynamic and interactive view among the microenvironments, the cellular and molecular heterogeneities, and the basic aspects of the vessel formation processes make the available knowledge largely fragmented. The neovascularisation processes, termed vasculogenesis, angiogenesis, arteriogenesis, and lymphangiogenesis, are important to the formation and proper functioning of organs and tissues both in the embryo and the postnatal period. These processes are intrinsically related to microvascular cells, such as endothelial and mural cells. These cells are able to adjust their activities in r…
The Role of Osteoprotegerin and Its Ligands in Vascular Function
2019
International audience; The superfamily of tumor necrosis factor (TNF) receptors includes osteoprotegerin (OPG) and its ligands, which are receptor activators of nuclear factor kappa-B ligand (RANKL) and TNF-related apoptosis-inducing ligand (TRAIL). The OPG/RANKL/RANK system plays an active role in pathological angiogenesis and inflammation as well as cell survival. It has been demonstrated that there is crosstalk between endothelial cells and osteoblasts during osteogenesis, thus establishing a connection between angiogenesis and osteogenesis. This OPG/RANKL/RANK/TRAIL system acts on specific cell surface receptors, which are then able to transmit their signals to other intracellular comp…
Cytoprotective and antioxidant properties of organic selenides for the myelin-forming cells, oligodendrocytes.
2018
Abstract Here a new series of twenty-one organoselenides, of potential protective activity, were synthesized and tested for their intrinsic cytotoxicity, anti-apoptotic and antioxidant capacities in oligodendrocytes. Most of the organoselenides were able to decrease the ROS levels, revealing antioxidant properties. Compounds 5b and 7b showed a high glutathione peroxidase (GPx)-like activities, which were 1.5 folds more active than ebselen. Remarkably, compound 5a diminished the formation of the oligodendrocytes SubG1 peak in a concentration-dependent manner, indicating its anti-apoptotic properties. Furthermore, based on the SwissADME web interface, we performed an in-silico structure-activ…
Pinolenic acid ameliorates oleic acid-induced lipogenesis and oxidative stress via AMPK/SIRT1 signaling pathway in HepG2 cells
2019
Pinolenic acid (PLA), a natural compound isolated from pine nut oil, has been reported to exert bioactivity against lipid anabolism. Nonetheless, the underlying mechanisms still poorly elucidated. The aim of this study is to comprehensively demonstrate the effects of PLA on oleic acid (OA)-induced non-alcoholic fatty liver disease (NAFLD) and their relationship with the lipid metabolic regulation. The results demonstrated that treatment with PLA dramatically inhibited lipid accumulation, oxidative stress as well as inflammatory responses induced by oleic acid in HepG2 cells. PLA also obviously decreased the levels of cellular triglyceride (TG), total cholesterol (TC), malondialdehyde (MDA),…
Peripheral artery disease, redox signaling, oxidative stress – Basic and clinical aspects
2017
Reactive oxygen and nitrogen species (ROS and RNS, e.g. H2O2, nitric oxide) confer redox regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. At higher concentrations, ROS and RNS lead to oxidative stress and oxidative damage of biomolecules (e.g. via formation of peroxynitrite, fenton chemistry). Peripheral artery disease (PAD) is characterized by severe ischemic conditions in the periphery leading to intermittent claudication and critical limb ischemia (end stage). It is well known that redox biology and oxidative stress play an important role in this setting. We here discuss the major pathways of oxidative stress and re…
Mild Parkinsonian Signs in a Hospital-based Cohort of Mild Cognitive Impairment Types: A Cross-sectional Study
2018
Background:Mild Parkinsonian Signs (MPS) have been associated with Mild Cognitive Impairment (MCI) types with conflicting results.Objective:To investigate the association of individual MPS with different MCI types using logistic ridge regression analysis, and to evaluate for each MCI type, the association of MPS with caudate atrophy, global cerebral atrophy, and the topographical location of White Matter Hyperintensities (WMH), and lacunes.Methods:A cross-sectional study was performed among 1,168 subjects with different types of MCI aged 45-97 (70,52 ± 9,41) years, who underwent brain MRI. WMH were assessed through two visual rating scales. The number and location of lacunes were also rated…
Theabrownin triggersDNAdamage to suppress human osteosarcoma U2OScells by activating p53 signalling pathway
2018
Abstract Osteosarcoma becomes the second leading cause of cancer death in the younger population. Current outcomes of chemotherapy on osteosarcoma were unsatisfactory to date, demanding development of effective therapies. Tea is a commonly used beverage beneficial to human health. As a major component of tea, theabrownin has been reported to possess anti‐cancer activity. To evaluate its anti‐osteosarcoma effect, we established a xenograft model of zebrafish and employed U2OS cells for in vivo and in vitro assays. The animal data showed that TB significantly inhibited the tumour growth with stronger effect than that of chemotherapy. The cellular data confirmed that TB‐triggered DNA damage an…
Total coumarins of Hedyotis diffusa induces apoptosis of myelodysplastic syndrome SKM-1 cells by activation of caspases and inhibition of PI3K/Akt pa…
2016
Abstract Ethnopharmacological relevance Hedyotis diffusa is an ethno-medicine used for anti-cancer treatment in the clinic of traditional Chinese medicine (TCM). The total coumarins of Hedyotis diffusa (TCHD) was a selected extract with observed antiproliferative activity, which has not been tested in treatment of myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML). Aim of the study This study aimed to evaluate the apoptosis-inducing effect of TCHD on human MDS cell line (SKM-1) and explore its action mechanism in association with caspase family and PI3K/Akt signaling pathway. Materials and methods The chemical constituents and total coumarins content of TCHD were determined by …
Gene Expression and Apoptosis Levels in Cumulus Cells of Patients with Polymorphisms of FSHR and LHB Undergoing in Vitro Fertilization Program
2017
Background/Aims: FSH receptor (FSHR) Ala307Thr and Asn680Ser and LHβ chain (LHB) Trp28Arg and Ile35Thr polymorphisms affect the response to pharmacological ovarian stimulation with r-FSH in women undergoing assisted reproductive treatment (ART). Here, we evaluated the expression level of selected genes involved in follicle maturation and the possible onset of apoptosis in cumulus cells of patients with single and double FSHR and LHB polymorphisms, as potential markers of oocyte competence. Methods: Cumulus cells from 36 stimulated patients were collected and SNP genotyping performed by PCR. Gene expression was evaluated through real-time PCR, and apoptosis estimated via TUNEL assay, and cle…