Todddeleon8747

The mRNA expression of ANGPTL4 and LPL as well as LPL activity were analyzed in the biopsies. RESULTS In both studies, GH increased serum FFA levels, upregulated ANGPTL4 mRNA expression and suppressed LPL activity. In study 2, acipimox completely suppressed FFA levels and antagonized the effects of GH on ANGPTL4 and LPL. CONCLUSIONS These human in vivo studies demonstrate that GH upregulates ANGPTL4 mRNA and suppresses LPL activity via an FFA-dependent mechanism. BACKGROUND S100A4 is a metastasis-associated protein also reported as a promising marker for dysfunctional white adipose tissue (WAT) and insulin resistance (IR) in adult and adolescent populations. OBJECTIVE We aimed to evaluate the association between the protein S100A4 and obesity and IR in children and during pubertal development. DESIGN AND METHODS The study design consisted of three cross-sectional populations of 249, 11 and 19 prepubertal children respectively (named study population 1, 2 and 3), and a longitudinal population of 53 girls undergoing sexual maturation (study population 4). All subjects were classified into experimental groups according to their sex, obesity and IR status. All study populations counted on anthropometry, glucose, and lipid metabolism, inflammation and cardiovascular biomarkers as well as S100A4 plasma levels measured. The study population 1 was intended as the discovery population in which to elucidate the relationship between Obesity-IR and S100A4 plasma levels in prepubes. We further reported an association between visceral WAT (vWAT) S100A4 expression and HOMA-IR, insulin levels and BMI Z-Score, but not with circulating S100A4. CONCLUSIONS We report for the first time the association of S100A4 with IR and WAT dysfunction in prepubertal populations as well as how the change in plasma S100A4 levels accompanies longitudinal trajectories of IR in children during pubertal development. Moreover, we propose epigenetic changes in two methylation sites and an altered S100A4 vWAT expression as plausible molecular mechanisms underlying this disturbance in obesity. https://www.selleckchem.com/products/FTY720.html BACKGROUND Apolipoprotein A-I (ApoA-I) is involved in reverse cholesterol transport as a major component of HDL, but also conveys anti-thrombotic, anti-oxidative, anti-inflammatory and immune-regulatory properties that are pertinent to its protective roles in cardiovascular, inflammatory and malignant pathologies. Despite the pleiotropy in ApoA-I functions, the regulation of intracellular ApoA-I levels remains poorly explored. METHODS HepG2 hepatoma cells and primary mouse hepatocytes were used as in vitro models to study the impact of genetic and chemical inhibitors of autophagy and the proteasome on ApoA-I by immunoblot, immunofluorescence and electron microscopy. Different growth conditions were implemented in conjunction with mTORC inhibitors to model the influence of nutrient scarcity versus sufficiency on ApoA-I regulation. Hepatic ApoA-I expression was also evaluated in high fat diet-fed mice displaying blockade in autophagy. RESULTS Under nutrient-rich conditions, basal ApoA-I levels in liver cells are sustained by the balancing act of autophagy and of mTORC1-dependent de novo protein synthesis. ApoA-I proteolysis occurs through a canonical autophagic pathway involving Beclin1 and ULK1 and the receptor protein p62/SQSTM1 that targets ApoA-I to autophagosomes. However, upon aminoacid insufficiency, suppression of ApoA-I synthesis prevails, rendering mTORC1 inactivation dispensable for autophagy-mediated ApoA-I proteolysis. CONCLUSION These data underscore the major contribution of post-transcriptional mechanisms to ApoA-I levels which differentially involve mTORC1-dependent signaling to protein synthesis and autophagy, depending on nutrient availability. Given the established role of ApoA-I in HDL-mediated reverse cholesterol transport, this mode of ApoA-I regulation may reflect a hepatocellular response to the organismal requirement for maintenance of cholesterol and lipid reserves under conditions of nutrient scarcity. Interleukin-3 (IL-3) is an important hematopoietic growth factor and immunregulatory cytokine. Although activated T helper cells represent a main source of IL-3, other cell types have been reported to express this cytokine. However, precise identification and quantification of the cells that produce IL-3 in vivo have not been performed. Therefore, we used a CRISPR/Cas approach to engineer mice containing a bicistronic mRNA linking a readily identifiable reporter, enhanced green fluorescent protein (ZsGreen1), to IL-3 expression. To characterize these novel reporter mice, we first examined ZsGreen1 expression by CD4 T cells subsets primed and activated in vitro. We found that activated Th1 cells expressed ∼4-fold higher levels of ZsGreen1 as compared to Th0 and Th2 cells. Endogenous IL-3 expression remained intact although reporter Th1 cells secreted ∼33 % less IL-3 than similarly activated wild-type cells. To characterize the ability of reporter mice to accurately mark IL-3-producing cells in vivo, we infected mice with Nippostrongylus brasiliensis. Low but significant numbers of ZsGreen1+ CD4 T cells were detected in the mesenteric lymph nodes and lung following both primary and secondary infection. No difference in basophil and intestinal mast cell numbers were observed between infected reporter and wild-type mice indicating that reporter mice secreted IL-3 levels in vivo that results in IL-3-driven biological activities which are indistinguishable from those observed in corresponding wild-type mice. These IL-3 reporter mice will be a valuable resource to investigate IL-3-dependent immune responses in vivo. BACKGROUND & AIMS Visceral hypersensitivity is common in patients with irritable bowel syndrome (IBS). We investigated whether inflammatory molecules, such as histamine and proteases, activate prostaglandin-endoperoxide synthase 2 (PTGS2, also called COX2) to increase the synthesis of prostaglandin E2 (PGE2) by mast cells, which activates the receptor PTGER2 (also called EP2) in the dorsal root ganglia to promote visceral hypersensitivity. METHODS We used an ELISA to measure levels of spontaneous release of molecules from mast cells in colonic mucosa from patients with IBS with diarrhea (IBS-D; 18 women and 5 men; ages 28 to 60 y), healthy individuals (controls, n=24), mice, and rats. We measured visceromotor responses to colorectal distension in rodents following intracolonic administration of colon biopsy supernatants, histamine, PGE2, a small interfering RNA against EP2, or an agonist of F2R like trypsin receptor 1 (F2RL1, also called PAR2). We investigated the role of COX2, produced by mast cells, in mediation of visceral hypersensitivity using mice with the Y385F substitution in Ptgs2 (Ptgs2Y385F mice), mast cell-deficient (W/WV) mice, and W/WV mice given injections of mast cells derived from wild-type or Ptgs2Y385F mice.