Affiliations: [a] Department of Biochemistry and Molecular Vascular Biology, Kanazawa University, Graduate School of Medical Science, Kanazawa, Japan | [b] Division of Tracer Kinetics, Advanced Science Research Center, Kanazawa University, Kanazawa, Japan | [c] Department of Biochemistry, Kanazawa Medical University School of Medicine, Uchinada, Japan | [d] Department of Neurosurgery, Kanazawa University, Graduate School of Medical Science, Kanazawa, Japan
Correspondence:
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Correspondence to: Seiichi Munesue and Yasuhiko Yamamoto, Department of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, 920-8640 Kanazawa, Japan. Tel.: +81 76 265 2181; Fax: +81 76 234 4217; E-mail: smunesue@med.kanazawa-u.ac.jp and yasuyama@med.kanazawa-u.ac.jp.
Abstract: The cell-surface receptor for advanced glycation end-products (RAGE) has been implicated in the development of diabetic vascular complications and Alzheimer's disease. RAGE has been considered to be involved in amyloid-β1-42 (Aβ1-42) uptake into brain. In the present study, we demonstrate that endogenous secretory RAGE (esRAGE), a decoy form of RAGE generated by alternative RNA processing, is able to inhibit Aβ1-42 influx into mouse brain. Surface plasmon resonance and competitive binding assays revealed that human Aβ1-42 interacted with human esRAGE within the immunoglobulin V type region. We next examined the uptake and distribution of 125I-labeled human Aβ1-42 in various organs and body fluids of newly created mice overexpressing human esRAGE as well as RAGE-null and wild-type (WT) mice. The transition of the 125I-labeled Aβ1-42 from circulation to brain parenchyma peaked at 30 min after the injection into WT mice, but this was significantly blunted in esRAGE-overexpressing and RAGE-null mice. Significant reduction in 125I-labeled Aβ1-42-derived photo-stimulated luminescence were marked in ventricles, cerebral cortex, hippocampus, especially CA1 and CA3 regions, putamen, and thalamus. The results thus suggest the potential of esRAGE in protection against the development of Alzheimer's disease.
