Inhibition of stearoyl-CoA desaturase 1 in the mouse impairs pancreatic islet morphogenesis and promotes loss of β-cell identity and α-cell expansion in the mature pancreas.

Abnormalities that characterize the pathophysiology of type 2 diabetes (T2D) include deficiencies of β-cells and the expansion of α-cells in pancreatic islets, manifested by lower insulin release and glucagon oversecretion. The molecular mechanisms that determine intra-islet interactions between pancreatic α- and β-cells are still not fully understood. The present study showed that stearoyl-coenzyme A (CoA) desaturase 1 (SCD1), an enzyme that is implicated in fatty acid metabolism, serves as a checkpoint in the control of endocrine cell equilibrium in pancreatic islets.

gP2S, an Information Management System for CryoEM Experiments.

Cryogenic electron microscopy (cryoEM) has become an integral part of many drug-discovery projects because crystallography of the protein target is not always achievable and cryoEM provides an alternative means to support structure-based ligand design. When dealing with a large number of distinct projects, and within each project a potentially large number of ligand-protein co-structures, accurate record keeping rapidly becomes challenging. Many experimental parameters are tuned for each target, including at the sample preparation, grid preparation, and microscopy stages.

Calcium Signaling in Glioma Cells: The Role of Nucleotide Receptors.

Calcium signaling is probably one of the evolutionary oldest and the most common way by which the signal can be transmitted from the cell environment to the cytoplasmic calcium binding effectors. Calcium signal is fast and due to diversity of calcium binding proteins it may have a very broad effect on cell behavior. Being a crucial player in neuronal transmission it is also very important for glia physiology.

Cross-Talk in Nucleotide Signaling in Glioma C6 Cells.

The chapter is focused on the mechanism of action of metabotropic P2Y nucleotide receptors: P2Y, P2Y, P2Y, P2Y and the ionotropic P2X receptor in glioma C6 cells. P2Y and P2Y both respond to ADP, but while P2Y links to PLC and elevates cytosolic Ca concentration, P2Y negatively couples to adenylate cyclase, maintaining cAMP at low level. In glioma C6, these two P2Y receptors modulate activities of ERK1/2 and PI3K/Akt signaling and the effects depend on physiological conditions of the cells.

Microglia is a key player in the reduction of stroke damage promoted by the new antithrombotic agent ticagrelor.

The ADP-responsive P2Y12 receptor is expressed on both platelets and microglia. Clinical data show that ticagrelor, a direct-acting, reversibly binding P2Y12-receptor antagonist, reduces total cardiovascular events, including stroke. In our present study, we investigated the expression of P2Y12 receptors and the effects of ticagrelor on brain injury in Sprague-Dawley rats subjected to a permanent middle cerebral artery occlusion (MCAo).

[Recently identified GPR17 receptors--characteristics and role in pathology of the nervous system].

Newly identified metabotropic GPR17 receptors are structurally related to purinergic P2Y receptors and cysteinyl leukotriene receptors. Re- cent studies showed that they play an important role in maturation of oligodendrocyte precursor cells. This review describes structure and pharmacological characterization of GPR17 receptors.

P2Y1 nucleotide receptor silencing and its effect on glioma C6 calcium signaling.

In our earlier studies of the signaling cross-talk between nucleotide receptors in an in vitro glioma model (C6 cell line) under prolonged serum deprivation conditions, a growth arrest of the cells and expression shift from P2Y(1) to P2Y(12) receptors was found. The aim of the present work was to test if siRNA silencing of P2Y(1) receptor changes P2Y(12) expression similarly as following the serum deprivation and which physiological downstream pathways it affects. Here we demonstrate for the first time the efficiency of siRNA technology in silencing P2Y nucleotide receptors in glioma C6 cell line.

Calcium signaling in glioma cells--the role of nucleotide receptors.

Calcium signaling is probably one of the evolutionary oldest and the most common way by which the signal can be transmitted from the cell environment to the cytoplasmic calcium binding effectors. Calcium signal is fast and due to diversity of calcium binding proteins it may have a very broad effect on cell behavior. Being a crucial player in neuronal transmission it is also very important for glia physiology.

Cross-talk in nucleotide signaling in glioma C6 cells.

The chapter is focused on the mechanism of action of metabotropic P2Y nucleotide receptors: P2Y(1), P2Y(2), P2Y(12), P2Y(14) and the ionotropic P2X(7) receptor in glioma C6 cells. P2Y(1) and P2Y(12) both respond to ADP, but while P2Y(1) links to PLC and elevates cytosolic Ca(2+) concentration, P2Y(12) negatively couples to adenylate cyclase, maintaining cAMP at low level. In glioma C6, these two P2Y receptors modulate activities of ERK1/2 and PI3K/Akt signaling and the effects depend on physiological conditions of the cells.

Is MLC phosphorylation essential for the recovery from ROCK inhibition in glioma C6 cells?

Inhibition of Rho-associated protein kinase (ROCK) activity in glioma C6 cells induces changes in actin cytoskeleton organization and cell morphology similar to those observed in other types of cells with inhibited RhoA/ROCK signaling pathway. We show that phosphorylation of myosin light chains (MLC) induced by P2Y₂ receptor stimulation in cells with blocked ROCK correlates in time with actin cytoskeleton reorganization, F-actin redistribution and stress fibers assembly followed by recovery of normal cell morphology. Presented results indicate that myosin light-chain kinase (MLCK) is responsible for the observed phosphorylation of MLC.

Regulation of subcellular localization of muscle FBPase in cardiomyocytes. The decisive role of calcium ions.

Glyconeogenesis, the synthesis of glycogen from carbohydrate precursors like lactate, seems to be an important pathway participating in replenishing glycogen in cardiomyocytes. Fructose-1,6-bisphosphatase (FBPase), an indispensible enzyme of glyconeogenesis, has been found in cardiomyocytes on the Z-line, in the nuclei and in the intercalated discs. Glyconeogenesis may proceed only when FBPase accumulates on the Z-line.