Autism Spectrum Disorder (ASD or autism) is a phenotypically and etiologically heterogeneous condition. Identifying biomarkers of clinically significant metabolic subtypes of autism could improve understanding of its underlying pathophysiology and potentially lead to more targeted interventions. We hypothesized that the application of metabolite-based biomarker techniques using decision thresholds derived from quantitative measurements could identify autism-associated subpopulations.
View Article and Find Full Text PDFIdentification of early biomarkers of heart injury and drug-induced cardiotoxicity is important to eliminate harmful drug candidates early in preclinical development and to prevent severe drug effects. The main objective of this study was to investigate the expression of microRNAs (miRNAs) in human-induced pluripotent stem cell cardiomyocytes (hiPSC-CM) in response to a broad range of cardiotoxic drugs. Next generation sequencing was applied to hiPSC-CM treated for 72 h with 40 drugs falling into the categories of functional (i.
View Article and Find Full Text PDFAutism spectrum disorder (ASD) is biologically and behaviorally heterogeneous. Delayed diagnosis of ASD is common and problematic. The complexity of ASD and the low sensitivity of available screening tools are key factors in delayed diagnosis.
View Article and Find Full Text PDFImplementing screening assays that identify functional and structural cardiotoxicity earlier in the drug development pipeline has the potential to improve safety and decrease the cost and time required to bring new drugs to market. In this study, a metabolic biomarker-based assay was developed that predicts the cardiotoxicity potential of a drug based on changes in the metabolism and viability of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM). Assay development and testing was conducted in 2 phases: (1) biomarker identification and (2) targeted assay development.
View Article and Find Full Text PDFBackground: Autism spectrum disorder (ASD) is behaviorally and biologically heterogeneous and likely represents a series of conditions arising from different underlying genetic, metabolic, and environmental factors. There are currently no reliable diagnostic biomarkers for ASD. Based on evidence that dysregulation of branched-chain amino acids (BCAAs) may contribute to the behavioral characteristics of ASD, we tested whether dysregulation of amino acids (AAs) was a pervasive phenomenon in individuals with ASD.
View Article and Find Full Text PDFThe relative developmental toxicity potency of a series of retinoid analogues was evaluated using a human induced pluripotent stem (iPS) cell assay that measures changes in the biomarkers ornithine and cystine. Analogue potency was predicted, based on the assay endpoint of the ornithine/cystine (o/c) ratio, to be all-trans-retinoic acid>TTNPB>13-cis-retinoic acid≈9-cis-retinoic acid>acitretin>etretinate>retinol. These rankings correlate with in vivo data and demonstrate successful application of the assay to rank a series of related toxic and non-toxic compounds.
View Article and Find Full Text PDFBackground: The diagnosis of autism spectrum disorder (ASD) at the earliest age possible is important for initiating optimally effective intervention. In the United States the average age of diagnosis is 4 years. Identifying metabolic biomarker signatures of ASD from blood samples offers an opportunity for development of diagnostic tests for detection of ASD at an early age.
View Article and Find Full Text PDFBirth Defects Res B Dev Reprod Toxicol
August 2013
A metabolic biomarker-based in vitro assay utilizing human embryonic stem (hES) cells was developed to identify the concentration of test compounds that perturbs cellular metabolism in a manner indicative of teratogenicity. This assay is designed to aid the early discovery-phase detection of potential human developmental toxicants. In this study, metabolomic data from hES cell culture media were used to assess potential biomarkers for development of a rapid in vitro teratogenicity assay.
View Article and Find Full Text PDFTransporters for vitamin C and its oxidized form dehydroascorbic acid (DHA) are crucial to maintain physiological concentrations of this important vitamin that is used in a variety of biochemical processes. The human SLC23 family consists of the Na(+)-dependent vitamin C transporters SVCT1 (encoded by the SLC23A1 gene) and SVCT2 (SLC23A2) as well as an orphan transporter SVCT3 (SLC23A3). Phylogenetically, the SLC23 family belongs to the nucleobase-ascorbate transporter (NAT) family, although no nucleobase transport has yet been demonstrated for the human members of this family.
View Article and Find Full Text PDFThe field of transport biology has steadily grown over the past decade and is now recognized as playing an important role in manifestation and treatment of disease. The SLC (solute carrier) gene series has grown to now include 52 families and 395 transporter genes in the human genome. A list of these genes can be found at the HUGO Gene Nomenclature Committee (HGNC) website (see www.
View Article and Find Full Text PDFSystemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new products (such as nanoparticles or cell therapies), the limited predictivity of traditional tests for human health effects, duration and costs of current approaches, and animal welfare considerations. The latter holds especially true in the context of the scheduled 2013 marketing ban on cosmetic ingredients tested for systemic toxicity.
View Article and Find Full Text PDFProtein tyrosine phosphatase PRL-3 mRNA was found highly expressed in colon cancer endothelium and metastases. We sought to associate a function with PRL-3 expression in both endothelial cells and malignant cells using in vitro models. PRL-3 mRNA levels were determined in several normal human endothelial cells exposed or unexposed to the phorbol ester phorbol 12-myristate 13-acetate (PMA) and in 27 human tumor cell lines.
View Article and Find Full Text PDFTolevamer, (GT160-246), is a sodium salt of styrene sulfonate polymer that is under development for the treatment of diarrhea caused by infection with Clostridium difficile. Pulsed ultrafiltration binding experiments in phosphate buffer containing 0.15 M Na(+) provide per polymer chain dissociation constants of 133 nM and 8.
View Article and Find Full Text PDFEzetimibe (SCH 58235) and SCH 48461 are potent cholesterol absorption inhibitors, which cause significant decreases in plasma cholesterol levels in cholesterol-fed animals and in humans with hypercholesterolemia. These compounds selectively block intestinal uptake and absorption of cholesterol. These cholesterol absorption inhibitors cause modest, inconsistent reductions in plasma cholesterol levels in animals fed cholesterol-free chow diets.
View Article and Find Full Text PDFZhongguo Yao Li Xue Bao
September 1998
Aim: To study the wiedendiol-A (W-A) inhibition mechanism of plasma cholesteryl ester (CE) transfer protein (CETP) on the transfer of CE.
Methods: Using gel filtration method.
Results: W-A at 30 mumol.
GR231118, BW1911U90, Bis(31/31')[[Cys31, Trp32, Nva34] neuropeptide Y(31-36)] (T-190) and [Trp-Arg-Nva-Arg-Tyr]2-NH2 (T-241) are peptide analogs of the C-terminus of neuropeptide Y that have recently been shown to be antagonists of the neuropeptide Y Y1 receptor. In this study, the activity of these peptides at each of the cloned neuropeptide Y receptor subtypes is determined in radioligand binding assays and in functional assays (inhibition of forskolin-stimulated cAMP formation). GR231118 is a potent antagonist at the human and rat neuropeptide Y Y1 receptors (pA2 = 10.
View Article and Find Full Text PDFGalanin mediates diverse physiological functions in digestive, endocrine, and central nervous systems through G-protein-coupled receptors. Two galanin receptors have been cloned but the gene structures are unknown. We report genomic and cDNA cloning of the mouse GalR1 galanin receptor and demonstrate that the coding sequence is uniquely divided into three exons encoding the N-terminal portion through the fifth transmebrane domain, the third intracellular loop, and the sixth transmembrane domain through the C-terminus.
View Article and Find Full Text PDFA series of azetidinone cholesterol absorption inhibitors related to SCH 48461 ((-)-6) has been prepared, and compounds were evaluated for their ability to inhibit hepatic cholesteryl ester formation in a cholesterol-fed hamster model. Although originally designed as acyl CoA: cholesterol acyltransferase (ACAT) inhibitors, comparison of in vivo potency with in vitro activity in a microsomal ACAT assay indicates no correlation between activity in these two models. The molecular mechanism by which these compounds inhibit cholesterol absorption is unknown.
View Article and Find Full Text PDFConformational restriction of previously disclosed acyclic (diphenylethyl)diphenylacetamides led to the discovery of several potent inhibitors of acyl CoA:cholesterol acyltransferase (ACAT). cis-[2-(4-Hydroxyphenyl)-1-indanyl]diphenylacetamide (4a) was the most potent ACAT inhibitor identified (IC50 = 0.04 microM in an in vitro rat hepatic microsomal ACAT assay, ED50 = 0.
View Article and Find Full Text PDFAmides of some substituted 1,2-diarylethylamines have been shown to exhibit potent acylCoA:cholesterol acyltransferase (ACAT, EC 2.3.1.
View Article and Find Full Text PDFSubstituted (1,2-diarylethyl)amides have been prepared and evaluated for their ability to inhibit microsomal acyl-CoA:cholesterol acyltransferase activity in vitro and to lower hepatic cholesteryl ester content in vivo in a cholesterol-fed hamster. Simple unsubstituted (diarylethyl)amides were potent inhibitors in vitro but showed poor activity in vivo. Introduction of polar groups at specific locations on the diarylethylamine moiety decreased in vitro activity but increased in vivo activity.
View Article and Find Full Text PDFThe amount of cholesterol that circulates in the plasma as lipoproteins can be affected by the balance of cholesterol metabolism within and between the intestines and liver. In the present report, we describe a novel hypocholesterolemic agent and document its pharmacological effects in animal models of hypercholesterolemia. The oral administration of (3R,4S)-1,4-bis-(4-methoxyphenyl)-3-(3-phenylpropyl)-2-azetidinone (SCH 48461) reduced plasma cholesterol concentrations in cholesterol-fed hamsters, rats and rhesus monkeys with ED50s of 1, 2 and 0.
View Article and Find Full Text PDFAcyl CoA: cholesterol acyltransferase (ACAT) inhibitors are known to inhibit cholesterol absorption and are under investigation to reduce hypercholesterolemia. These studies examine the effect of an ACAT inhibitor 2,2-dimethyl-N-(2,4,6-trimethoxyphenyl)-dodecanamide (PD128042) on the uptake, metabolism and secretion of cholesterol by the hamster intestinal wall in a short-term model. Preliminary studies in this model indicated that the uptake of 14C-cholesterol and its subsequent esterification 2 hr postoral dosing occurs primarily in the duodenal and jejunal segments of the small intestine and most of the radiolabeled cholesterol and cholesteryl ester in the plasma was associated with chylomicrons.
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