Peptide loading of MHC class II (MHCII) molecules is facilitated by HLA-DM (DM), which catalyzes CLIP release, stabilizes empty MHCII, and edits the MHCII-bound peptide repertoire. HLA-DO (DO) binds to DM and modulates its activity, resulting in an altered set of peptides presented at the cell surface. MHCII-peptide presentation in individuals with type 1 diabetes (T1D) is abnormal, leading to a breakdown in tolerance; however, no direct measurement of the MHCII pathway activity in T1D patients has been performed.
View Article and Find Full Text PDFGolimumab was recently evaluated in a phase 2a, randomized, double-blind, placebo-controlled, multicenter study (T1GER study) for safety and efficacy in children and young adults with newly diagnosed type 1 diabetes (T1D). Golimumab showed significant treatment effect where endogenous insulin production was preserved and clinical and metabolic parameters were improved. The objective of this report was to evaluate pharmacokinetic (PK) and pharmacodynamic data from the T1GER study by developing a population pharmacokinetic (PopPK) model and performing exposure-response (ER) analyses.
View Article and Find Full Text PDFObjective: The T1GER (A Study of SIMPONI to Arrest β-Cell Loss in Type 1 Diabetes) study showed many metabolic benefits of the tumor necrosis factor-α blocker golimumab in children and young adults with type 1 diabetes (T1D). Off-therapy effects are reported.
Research Designs And Methods: T1GER was a phase 2, placebo-controlled, randomized trial in which golimumab or placebo was administered for 52 weeks to participants 6-21 years old diagnosed with T1D within 100 days of randomization.
Autoantibody screening in type 1 diabetes (T1D) may reduce the chances of potentially life-threatening diabetic ketoacidosis (DKA) at diagnosis by allowing individuals at risk of progression to more actively monitor for and/or manage progression to insulin dependence. We investigated parents' preferences for treatments to delay the onset of insulin dependence in children who are at high risk of developing Stage III T1D. A web-based survey ( = 1501) was administered to a stratified sample of parents (children <18 years) in the United States from an online panel.
View Article and Find Full Text PDFType 1 diabetes, a disorder characterized by immune-mediated loss of functional pancreatic beta cells, is a disease continuum with specific presymptomatic stages with defined risk of progression to symptomatic disease. Prognostic biomarkers have been developed for disease staging and for stratification of subjects that address the heterogeneity in rate of disease progression. Using biomarkers for stratification of subjects at different stages of type 1 diabetes will enable smaller and shorter intervention clinical trials with greater effect size.
View Article and Find Full Text PDFFatty acid binding protein-4 (FABP4) and FABP5 are two closely related FA binding proteins expressed primarily in adipose tissue and/or macrophages. The small-molecule FABP4 inhibitor BMS309403 was previously reported to improve insulin sensitivity in leptin-deficient Lep(ob)/Lep(ob) (ob/ob) mice. However, this compound was not extensively characterized in the more physiologically relevant animal model of mice with diet-induced obesity (DIO).
View Article and Find Full Text PDFG-protein-coupled bile acid receptor 1 (GPBAR1/TGR5/M-Bar/GPR131) is a cell surface receptor involved in the regulation of bile acid metabolism. We have previously shown that Gpbar1-null mice are resistant to cholesterol gallstone disease when fed a lithogenic diet. Other published studies have suggested that Gpbar1 is involved in both energy homeostasis and glucose homeostasis.
View Article and Find Full Text PDFProprotein convertase subtilisin/kexin type 9 (PCSK9) induces degradation of low-density lipoprotein receptor (LDLR) in the liver. It is being pursued as a therapeutic target for LDL-cholesterol reduction. Earlier genome-wide gene expression studies showed that PCSK9 over-expression in HepG2 cells resulted in up-regulation of genes in cholesterol biosynthesis and down-regulation of genes in stress response pathways; however, it was not known whether these changes were directly regulated by PCSK9 or were secondary to PCSK9-induced changes to the intracellular environment.
View Article and Find Full Text PDFPCSK9 (proprotein convertase subtilisin/kexin type 9) mediates the post-translational degradation of the LDL receptor (LDLR) and, as a result, modulates serum levels of LDL-cholesterol (LDL-C). Individuals with gain-of-function mutations in the PCSK9 gene exhibit high serum levels of LDL-C, while those with loss-of-function mutations have low serum levels of LDL-C and are protected from heart disease. Similarly, mice lacking the expression of PCSK9 exhibit higher levels of LDLR in the liver and reduced serum cholesterol, while the overexpression of PCSK9 reduces LDLR and results in increased serum cholesterol.
View Article and Find Full Text PDFG protein-coupled receptor 119 (GPR119) is expressed in pancreatic islets and intestine, and is involved in insulin and incretin hormone release. GPR119-knockout (Gpr119(-/-)) mice were reported to have normal islet morphology and normal size, body weight (BW), and fed/fasted glucose levels. However, the physiological function of GPR119 and its role in maintaining glucose homeostasis under metabolic stress remain unknown.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2009
Neuromedin U (Nmu) is a neuropeptide expressed primarily in the gastrointestinal tract and central nervous system. Previous reports have identified two G protein-coupled receptors (designated Nmur1 and Nmur2) that bind Nmu. Recent reports suggest that Nmu mediates immune responses involving mast cells, and Nmur1 has been proposed to mediate these responses.
View Article and Find Full Text PDFObjective: FFAR1/GPR40 is a G-protein-coupled receptor expressed predominantly in pancreatic islets mediating free fatty acid-induced insulin secretion. However, the physiological role of FFAR1 remains controversial. It was previously reported that FFAR1 knockout (Ffar1(-/-)) mice were resistant to high-fat diet-induced hyperinuslinemia, hyperglycemia, hypertriglyceridemia, and hepatic steatosis.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2008
Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to low density lipoprotein receptor (LDLR) and induces its internalization and degradation. PCSK9 binding to LDLR is mediated through the LDLR epidermal growth factor-like repeat A (EGF-A) domain. We show for the first time that an EGF-A peptide inhibits PCSK9-mediated degradation of LDLR in HepG2 cells.
View Article and Find Full Text PDFMice lacking GPR103A expression display osteopenia. Analysis of mouse quantitative trait loci literature associated with bone mineral density suggested GPR103A ligand P518/Qrfp (chromosome 2qB) as a candidate osteoporosis gene. Promoter and coding regions of mouse P518/Qrfp were sequenced from genomic DNA obtained from the osteoporosis-prone strain SAMP6 and control strains SAMR1, A/J, AKR/J, BALB/c, C3H/HeJ, C57BL/6J, and DBA/2J.
View Article and Find Full Text PDFObjective: To compare outcomes of appendectomy in an Acute Care Surgery (ACS) model to that of a traditional home-call attending surgeon model.
Summary Background Data: Acute care surgery (ACS, a combination of trauma surgery, emergency surgery, and surgical critical care) has been proposed as a practice model for the future of general surgery. To date, there are few data regarding outcomes of surgical emergencies in the ACS model.
The Gpbar1 [G-protein-coupled BA (bile acid) receptor 1] is a recently identified cell-surface receptor that can bind and is activated by BAs, but its physiological role is unclear. Using targeted deletion of the Gpbar1 gene in mice, we show that the gene plays a critical role in the maintenance of bile lipid homoeostasis. Mice lacking Gpbar1 expression were viable, developed normally and did not show significant difference in the levels of cholesterol, BAs or any other bile constituents.
View Article and Find Full Text PDFBackground: Although the traditional role of radiology in trauma care has been diagnostic, therapeutic interventional radiology (IR) techniques have now become essential in the management of many injuries. We hypothesized that IR has evolved at our institution over the last decade from a largely diagnostic to a more therapeutic role in the care of the injured patient.
Methods: Demographic information, computed tomographic scans of the chest and abdomen, and angiographic procedures (APs) performed within 48 hours of admission were reviewed in all patients evaluated at a Level I trauma center for the periods 1993 to 1995 and 2000 to 2002.
This project identified a novel family of six 66-68 residue peptides from the venom of two Australian funnel-web spiders, Hadronyche sp. 20 and H. infensa: Orchid Beach (Hexathelidae: Atracinae), that appear to undergo N- and/or C-terminal post-translational modifications and conform to an ancestral protein fold.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2003
GPR54 is a G-protein-coupled receptor that displays a high percentage of identity in the transmembrane domains with the galanin receptors. The ligand for GPR54 has been identified as a peptide derived from the KiSS-1 gene. KiSS-1 has been shown to have anti-metastatic effects, suggesting that KiSS-1 or its receptor represents a potential therapeutic target.
View Article and Find Full Text PDFUnlabelled: PepPat, a hybrid method that combines pattern matching with similarity scoring, is described. We also report PepPat's application in the identification of a novel tachykinin-like peptide. PepPat takes as input a query peptide and a user-specified regular expression pattern within the peptide.
View Article and Find Full Text PDFBackground: The EST database provides a rich resource for gene discovery and in silico expression analysis. We report a novel computational approach to identify co-expressed genes using EST database, and its application to IL-8.
Results: IL-8 is represented in 53 dbEST cDNA libraries.