Intranasal Delivery of RGD Motif-Containing Osteopontin Icosamer Confers Neuroprotection in the Postischemic Brain via αvβ3 Integrin Binding.
Osteopontin (OPN) is a phosphorylated glycoprotein possessing an arginine-glycine-aspartate (RGD)-motif, which binds to several cell surface integrins and mediates a wide range of cellular processes. Inductions of OPN have been reported in the postischemic brain, and the neuroprotective effects of OPN have been demonstrated in animal models of stroke. In the present study, we showed a robust neuroprotective effect of RGD-containing icosamer OPN peptide (OPNpt20) in a rat model of focal cerebral ischemia (middle cerebral artery occlusion, MCAO). Intranasally administered OPNpt20 reduced mean infarct volume by 79.7 % compared to the treatment-naïve MCAO control animals and markedly ameliorated neurological deficits. In addition, OPNpt20 significantly suppressed the inductions of iNOS and of inflammatory markers in postischemic brains and in primary microglial cultures, demonstrating anti-inflammatory effects. Administration of a mutant peptide, in which RGD was replaced by arginine-alanine-alanine (RAA), failed to suppress infarct volumes in MCAO animals and co-administration of OPNpt20 with anti-αvβ3 integrin antibody failed to suppress iNOS induction in primary microglia culture, indicating that the RGD motif in OPNpt20 and endogenous αvβ3 integrin play critical roles. Furthermore, pull-down assay revealed a direct binding between OPNpt20 and αvβ3 integrin in primary microglia culture. Together, these results indicate that RGD-containing OPN icosamer has therapeutic potential in the postischemic brain and αvβ3 integrin-mediated anti-inflammatory effect might be an underlying mechanism.
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea.
Yin-Chuan
YC
Jin
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea.|Medical Research Center, Inha University School of Medicine, Inchon, South Korea.
Hahnbie
H
Lee
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea.|Medical Research Center, Inha University School of Medicine, Inchon, South Korea.
Seung-Woo
SW
Kim
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea.|Medical Research Center, Inha University School of Medicine, Inchon, South Korea.
Il-Doo
ID
Kim
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea.|Medical Research Center, Inha University School of Medicine, Inchon, South Korea.
Hye-Kyung
HK
Lee
Department of Brain and Cognitive Science, Ewha Womans University, Seoul, South Korea.
Yunjin
Y
Lee
Department of Brain and Cognitive Science, Ewha Womans University, Seoul, South Korea.
Pyung-Lim
PL
Han
Department of Anatomy, Inha University School of Medicine, 7-241 Shinheung-dong, Jung-Gu, Inchon, 400-712, Republic of Korea. jklee@inha.ac.kr.|Medical Research Center, Inha University School of Medicine, Inchon, South Korea. jklee@inha.ac.kr.
Ja-Kyeong
JK
Lee
D000281:Administration, Intranasal; D000595:Amino Acid Sequence; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D001921:Brain / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D002478:Cells, Cultured; D016503:Drug Delivery Systems; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000503:physiopathology; D039302:Integrin alphaVbeta3 / Q000378:metabolism*; D008297:Male; D017628:Microglia / Q000187:drug effects / Q000378:metabolism; D009043:Motor Activity; D000066829:Neuroprotection; D009569:Nitric Oxide / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D009842:Oligopeptides / Q000008:administration & dosage*; D053495:Osteopontin / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use*; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D020033:Protein Isoforms / Q000008:administration & dosage / Q000737:chemistry / Q000627:therapeutic use; D017207:Rats, Sprague-Dawley; D050794:STAT1 Transcription Factor / Q000378:metabolism
D000893:Anti-Inflammatory Agents; D039302:Integrin alphaVbeta3; D009573:Nitrites; D009842:Oligopeptides; D020033:Protein Isoforms; D050794:STAT1 Transcription Factor; D053495:Osteopontin; D009569:Nitric Oxide; C047981:arginyl-glycyl-aspartic acid; D052247:Nitric Oxide Synthase Type II
Icosamer; Inflammation; MCAO; Neuroprotection; Osteopontin; RGD