Skeletal muscle resistance to insulin is related to accumulation of lipid-derived products, but it is not clear whether this accumulation is caused by skeletal muscle mitochondrial dysfunction. Diabetes and obesity are reported to have a selective effect on the function of subsarcolemmal and interfibrillar mitochondria in insulin-resistant skeletal muscle. The current study investigated the role of the subpopulations of mitochondria in the pathogenesis of insulin resistance in the absence of obesity.
View Article and Find Full Text PDFCreatine kinetics were measured in young healthy subjects, eight males and seven females, age 20-30 years, after an overnight fast on creatine-free diet. Whole body turnover of glycine and its appearance in creatine was quantified using [1-(13)C] glycine and the rate of protein turnover was quantified using L-ring [(2)H5] phenylalanine. The creatine pool size was estimated by the dilution of a bolus [C(2)H3] creatine.
View Article and Find Full Text PDFMouse models of human diseases are used to study the metabolic and physiological processes leading to altered whole-body energy expenditure (EE), which is the sum of EE of all body organs and tissues. Isotopic techniques, arterio-venous difference of substrates, oxygen, and blood flow measurements can provide essential information to quantify tissue/organ EE and substrate oxidation. To complement and integrate experimental data, quantitative mathematical model analyses have been applied in the design of experiments and evaluation of metabolic fluxes.
View Article and Find Full Text PDFMolecular imaging of atherosclerotic biomarkers is critical for non-invasive detection and diagnosis of atherosclerotic plaques and therapeutic management. Fibrin and fibronectin accumulate at elevated levels in atherosclerotic plaques and are associated with atherogenesis and disease progression. Molecular imaging of these biomarkers has the potential to non-invasively characterize plaque burden.
View Article and Find Full Text PDFSynthetic small interfering RNA (siRNA) has become the basis of a new generation of gene-silencing cancer therapeutics. However, successful implementation of this novel therapy relies on the ability to effectively deliver siRNA into target cells and to prevent degradation of siRNA in lysosomes after endocytosis. In this study, our goal was to design and optimize new amphiphilic cationic lipid carriers that exhibit selective pH-sensitive endosomal membrane disruptive capabilities to allow for the efficient release of their siRNA payload into the cytosol.
View Article and Find Full Text PDFNonspecific association of serum molecules with short-interfering RNA (siRNA) nanoparticles can change their physiochemical characteristics, and results in reduced cellular uptake in the target tissue during the systemic siRNA delivery process. Serum albumin is the most abundant protein in the body and has been used to modify the surface of nanoparticles, to inhibit association of other serum molecules. Here, we hypothesized that surface modification of lipid-based nanoparticular siRNA delivery systems with albumin could prevent their interaction with serum proteins, and improve intracellular uptake.
View Article and Find Full Text PDFE-selectin, expressed on inflamed endothelium, and sialyl Lewis x (sLe(x)), present on the surface of leukocytes, play a key role in leukocyte-endothelial interactions during leukocyte recruitment to sites of inflammation. HECA-452 is a monoclonal antibody (mAb) that recognizes sLe(x) and is routinely used by investigators from diverse fields who seek to unravel the mechanisms of leukocyte adhesion. The data regarding the ability of HECA-452 to inhibit carbohydrate-mediated leukocyte adhesion to E-selectin remains conflicted, in part due to the presence of a variety of potential E-selectin reactive moieties on leukocytes.
View Article and Find Full Text PDF