Protein, and lipid-derived Advanced Glycoxidation Endproducts (AGE) have been linked to a spectrum of cellular oxidative responses leading to tissue injury via enhanced cytokine, growth factor, matrix production, vascular dysfunction, and atherogenesis. Vascular endothelial cells (EC) and other cells express a spectrum of AGE-binding proteins, some of which mediate endocytosis and clearance, but others trigger oxidant stress via ROS generation, and Nf-kB activation, contributing to inflammatory events, in a self perpetuating manner, which in the presence of diabetes, leads to accelerated atherogenesis. Based on presented evidence, we propose that in diabetes and/or aging normal AGE detoxification mechanisms are overwhelmed by marked increases in AGE burden, from exogenous and endogenous sources, and the resulting glycoxidant excess, together with other metabolites (glucose, lipids) leads to low-grade inflammatory state, underlying diabetes and diabetic vascular injury. The main goal of this Continuation proposal is to identify possible mechanisms by which environmental oxidant or carbonyl stress and systemic vascular toxicity can be balanced, either by enhancing AGE-receptor (AGER) mediated clearance or by inhibiting AGE-promoted inflammatory signaling cascades. This goal will be approached by assessing:
Aim 1 a: Early AGER signaling events of endocytotic pathways vs. Nf-kB activation pathways and of AGER-dependent negative or inhibitory cell activation pathways in endothelial cells or macrophages (Mf) over-expressing AGER1, R2, R3 and RAGE; 1b. Differences in AGER signaling in cells from aging mice, Aim 2a. Effects of environmental AGE stress on AGE-R clearance vs activation as a function of age in mice: in vitro studies, or 2b., in ApoE-deficient mice, a model of atherogenesis.
Aim 3 a: Effects of AGE-binding peptide, Lysozyme peptide (LZ-p) overexpression on AGER signaling, and 3b: In vivo effects of Lz-p on AGER-mediated clearance and tissue pathology in Lz-p transgenic mice, exposed to high AGE states, eg. diabetes, diet. The proposed studies will expand our understanding of this basic process and may allow us to identify ways to prevent AGE-induced vascular injury due to diabetes and aging.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG009453-14
Application #
6738022
Study Section
Special Emphasis Panel (ZRG1-MET (01))
Program Officer
Finkelstein, David B
Project Start
1992-01-15
Project End
2008-04-30
Budget Start
2004-05-15
Budget End
2005-04-30
Support Year
14
Fiscal Year
2004
Total Cost
$423,750
Indirect Cost
Name
Mount Sinai School of Medicine
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
078861598
City
New York
State
NY
Country
United States
Zip Code
10029
Schulman, Carl I; Uribarri, Jaime; Cai, Weijing et al. (2014) Increased circulating advanced glycation endproducts (AGEs) in acute trauma patients. Clin Chem Lab Med 52:103-8
Uribarri, Jaime; Cai, Weijing; Pyzik, Renata et al. (2014) Suppression of native defense mechanisms, SIRT1 and PPAR?, by dietary glycoxidants precedes disease in adult humans; relevance to lifestyle-engendered chronic diseases. Amino Acids 46:301-9
Vlassara, Helen; Uribarri, Jaime (2014) Advanced glycation end products (AGE) and diabetes: cause, effect, or both? Curr Diab Rep 14:453
Cai, Weijing; Ramdas, Maya; Zhu, Li et al. (2012) Oral advanced glycation endproducts (AGEs) promote insulin resistance and diabetes by depleting the antioxidant defenses AGE receptor-1 and sirtuin 1. Proc Natl Acad Sci U S A 109:15888-93
Uribarri, Jaime; Cai, Weijing; Ramdas, Maya et al. (2011) Restriction of advanced glycation end products improves insulin resistance in human type 2 diabetes: potential role of AGER1 and SIRT1. Diabetes Care 34:1610-6
Uribarri, Jaime; Woodruff, Sandra; Goodman, Susan et al. (2010) Advanced glycation end products in foods and a practical guide to their reduction in the diet. J Am Diet Assoc 110:911-16.e12
Cai, Weijing; He, John Cijiang; Zhu, Li et al. (2008) AGE-receptor-1 counteracts cellular oxidant stress induced by AGEs via negative regulation of p66shc-dependent FKHRL1 phosphorylation. Am J Physiol Cell Physiol 294:C145-52
Peppa, Melpomeni; Uribarri, Jaime; Vlassara, Helen (2008) Aging and glycoxidant stress. Hormones (Athens) 7:123-32
Vlassara, Helen; Uribarri, Jaime; Cai, Weijing et al. (2008) Advanced glycation end product homeostasis: exogenous oxidants and innate defenses. Ann N Y Acad Sci 1126:46-52
Linden, Ellena; Cai, Weijing; He, John C et al. (2008) Endothelial dysfunction in patients with chronic kidney disease results from advanced glycation end products (AGE)-mediated inhibition of endothelial nitric oxide synthase through RAGE activation. Clin J Am Soc Nephrol 3:691-8

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