Reduction of aluminum ion neurotoxicity through a

small peptide application e NAP treatment of Alzheimer's disease

Ming-Hui Yang ^a,b,c, Shih-Cheng Chen ^d, Yu-Fen Lin ^e, Yi-Chia Lee ^f, Ming-Yii Huang ^g,h, Ko-Chin Chen ⁱ, Hsin-Yi Wu ^j, Po-Chiao Lin ^k, Illana Gozes ^l,**, Yu-Chang Tyan ^{b,c,f,m,n,o,*}

^a Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan

^b Center for Infectious Disease and Cancer Research, Kaohsiung Medical University, Kaohsiung 807, Taiwan

^c Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan

^d Office of Research and Development, Kaohsiung Medical University, Kaohsiung 807, Taiwan

^e Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan

^f Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan

^g Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan

^h Department of Radiation Oncology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan

ⁱ Department of Pathology, Changhua Christian Hospital, Changhua 500, Taiwan

^j Instrumentation Center, National Taiwan University, Taipei 106, Taiwan

^k Department of Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan

^l Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Adams Super Center for Brain Studies and Sagol School for Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel

^m Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan

ⁿ Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 804, Taiwan

^o Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan

Alzheimer's disease (AD) is the most common cause of dementia in late life. It is difficult to precisely diagnose AD at early stages, making biomarker search essential for further developments. The objective of this study was to identify protein biomarkers associated with aluminum ions toxicity (AD-like toxicity) in a human neuroblastoma cell model, SHSY5Y and assess potential prevention by NAP (NAPVSIPQ). Complete proteomic techniques were implemented. Four proteins were identified as up-regulated with aluminum ion treatment, CBP80/20-dependent translation initiation factor (CTIF), Early endosome antigen 1 (EEA1), Leucine-rich repeat neuronal protein 4 (LRRN4) and Phosphatidylinositol 3-kinase regulatory subunit beta (PI3KR2). Of these four proteins, EEA1 and PI3KR2 were down-regulated after NAP-induced neuroprotective activity in neuroblastoma cells. Thus, aluminum ions may increase the risk for neurotoxicity in AD, and the use of NAP is suggested as a treatment to provide additional protection against the effects of aluminum ions, via EEA1 and PI3KR2, associated with sorting and processing of the AD amyloid precursor protein (APP) through the endosomal system.