Targeting Mitochondrial Calcium Uptake with the Natural Flavonol Kaempferol, to Promote Metabolism/Secretion Coupling in Pancreatic β-cells.

Pancreatic β-cells secrete insulin to lower blood glucose, following a meal. Maintenance of β-cell function is essential to preventing type 2 diabetes. In pancreatic β-cells, mitochondrial matrix calcium is an activating signal for insulin secretion.

Protein quantitative trait locus study in obesity during weight-loss identifies a leptin regulator.

Thousands of genetic variants have been associated with complex traits through genome-wide association studies. However, the functional variants or mechanistic consequences remain elusive. Intermediate traits such as gene expression or protein levels are good proxies of the metabolic state of an organism.

Role of sulfotransferases in resveratrol metabolism in human adipocytes.

Scope: Polyphenols such as resveratrol received interest for their wide-ranging biological benefits, including anti-obesity potential, mimicking effects of caloric restriction with reduced body fat and increased energy expenditure. However, resveratrol is rapidly metabolized, and it is not completely understood which form of resveratrol is responsible for the effects observed within target cells such as adipocytes. Also the role of metabolizing enzymes has not been investigated before.

Chemokine receptor CCR2 undergoes transportin1-dependent nuclear translocation.

Chemokines (CCs) are small chemoattractant cytokines involved in a wide variety of biological and pathological processes. Released by cells in the milieu, and extracellular matrix and activating signalling cascades upon binding to specific G protein-coupled receptors (GPCRs), they trigger many cellular events. In various pathologies, CCs are directly responsible for excessive recruitment of leukocytes to inflammatory sites and recent studies using chemokine receptor (CCR) antagonists permitted these molecules to reach the market for medical use.

Isoform-specific functions of phosphoinositide 3-kinases: p110 delta but not p110 gamma promotes optimal allergic responses in vivo.

The leukocyte-enriched p110gamma and p110delta isoforms of PI3K have been shown to control in vitro degranulation of mast cells induced by cross-linking of the high affinity receptor of IgE (FcepsilonRI). However, the relative contribution of these PI3K isoforms in IgE-dependent allergic responses in vivo is controversial. A side-by-side comparative analysis of the role of p110gamma and p110delta in mast cell function, using genetic approaches and newly developed isoform-selective pharmacologic inhibitors, confirms that both PI3K isoforms play an important role in FcepsilonRI-activated mast cell degranulation in vitro.

A chemical proteomics approach to phosphatidylinositol 3-kinase signaling in macrophages.

Prior work using lipid-based affinity matrices has been done to investigate distinct sets of lipid-binding proteins, and one series of experiments has proven successful in mammalian cells for the proteome-wide identification of lipid-binding proteins. However, most lipid-based proteomics screens require scaled up sample preparation, are often composed of multiple cell types, and are not adapted for simultaneous signal transduction studies. Herein we provide a chemical proteomics strategy that uses cleavable lipid "baits" with broad applicability to diverse biological samples.

Furan-2-ylmethylene thiazolidinediones as novel, potent, and selective inhibitors of phosphoinositide 3-kinase gamma.

Class I phosphoinositide 3-kinases (PI3Ks), in particular PI3Kgamma, have become attractive drug targets for inflammatory and autoimmune diseases. Here, we disclose a novel series of furan-2-ylmethylene thiazolidinediones as selective, ATP-competitive PI3Kgamma inhibitors. Structure-based design and X-ray crystallography of complexes formed by inhibitors bound to PI3Kgamma identified key pharmacophore features for potency and selectivity.

Blockade of PI3Kgamma suppresses joint inflammation and damage in mouse models of rheumatoid arthritis.

Phosphoinositide 3-kinases (PI3K) have long been considered promising drug targets for the treatment of inflammatory and autoimmune disorders as well as cancer and cardiovascular diseases. But the lack of specificity, isoform selectivity and poor biopharmaceutical profile of PI3K inhibitors have so far hampered rigorous disease-relevant target validation. Here we describe the identification and development of specific, selective and orally active small-molecule inhibitors of PI3Kgamma (encoded by Pik3cg).

Design and synthesis of the first generation of novel potent, selective, and in vivo active (benzothiazol-2-yl)acetonitrile inhibitors of the c-Jun N-terminal kinase.

Several lines of evidence support the hypothesis that c-Jun N-terminal kinase (JNKs) plays a critical role in a wide range of diseases including cell death (apoptosis)-related disorders (neurodegenerative diseases, brain, heart, and renal ischemia, epilepsy) and inflammatory disorders (multiple sclerosis, rheumatoid arthritis, inflammatory bowel diseases). Screening of our internal compound collection for inhibitors of JNK3 led to the identification of (benzothiazol-2-yl)acetonitrile derivatives as potent and selective JNK1, -2, -3 inhibitors. Starting from initial hit 1 (AS007149), the chemistry and initial structure-activity relationship (SAR) of this novel and unique kinase inhibitor template were explored.

Design, synthesis, and biological activity of novel, potent, and selective (benzoylaminomethyl)thiophene sulfonamide inhibitors of c-Jun-N-terminal kinase.

Several lines of evidence support the hypothesis that c-Jun N-terminal kinases (JNKs) play a critical role in a wide range of disease states including cell death (apoptosis)-related and inflammatory disorders (epilepsy, brain, heart and renal ischemia, neurodegenerative diseases, multiple sclerosis, rheumatoid arthritis, and inflammatory bowel syndrome). The screening of a compound collection led to the identification of a 2-(benzoylaminomethyl)thiophene sulfonamide (AS004509, compound I) as a potent and selective JNK inhibitor. Chemistry and structure--activity relationship (SAR) studies performed around this novel kinase-inhibiting motif indicated that the left and central parts of the molecule were instrumental to maintaining potency at the enzyme.

Involvement of phosphoinositide 3-kinase gamma, Rac, and PAK signaling in chemokine-induced macrophage migration.

In macrophages, chemotactic stimuli cause the activation of Rac and PAK, but little is known about the signaling pathways involved and their role in chemotactic gradient sensing. Herein, we report that in macrophages, the chemokine RANTES (regulated on activation normal T cell expressed and secreted)/CCL5 activates the small GTPase Rac and its downstream target PAK2 within seconds. This response depends on Gi activation and largely on the subsequent triggering of phosphoinositide 3-kinase gamma (PI3Kgamma) and Rac.