Jingxin Wang1, Robert Cunningham2, Henrik Zetterberg3,4,5, Sanjay Asthana6,7,8, Cynthia Carlsson6,7,8, Ozioma Okonkwo1,6,7,8, Lingjun Li1,9,10,11. 1. Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA. 2. Thermo Fisher Scientific, Rockford, IL. 3. Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden. 4. Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden. 5. Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK. 6. Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. 7. Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, Madison, WI, USA. 8. Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. 9. School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA. 10. Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA. 11. School of Life Sciences, Tianjin University, Tianjin, China.
Abstract
PURPOSE: The goal of this study is to investigate putative molecular dynamic changes in cerebrospinal fluids (CSFs) collected from individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD) as compared to healthy controls. EXPERIMENTAL DESIGN: The CSF samples from 12 subjects comprised of four cognitively normal individuals and eight patients with MCI and AD, respectively. Two aliquots of each CSF samples (total 1 mL) of each participant are used for this study. Endogenous peptide separations are performed using 10 000 molecular weight cut-off filters followed by LC-MS/MS identification and quantitation while lectin-enrichment chromatography is used to enrich glycoproteins in CSF followed by trypsin digestion and subsequent LC-MS/MS for shotgun identification and label-free quantitation. RESULTS: Using an optimized submicrogram peptide separation with molecular weight cut-off filtration and an in house-constructed database, 645 peptides are identified. Glycoproteins are enriched by lectin affinity chromatography, resulting in 795 identified proteins. The discovery and alterations of proSAAS-derived peptides and transthyretin are described and their roles in AD are discussed. CONCLUSIONS AND CLINICAL RELEVANCE: Comprehensive identification of endogenous CSF peptidome is achieved. Fifteen proteins are found to be differentially expressed among the three groups. The dynamic changes of transthyretin are reported for the first time.
PURPOSE: The goal of this study is to investigate putative molecular dynamic changes in cerebrospinal fluids (CSFs) collected from individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD) as compared to healthy controls. EXPERIMENTAL DESIGN: The CSF samples from 12 subjects comprised of four cognitively normal individuals and eight patients with MCI and AD, respectively. Two aliquots of each CSF samples (total 1 mL) of each participant are used for this study. Endogenous peptide separations are performed using 10 000 molecular weight cut-off filters followed by LC-MS/MS identification and quantitation while lectin-enrichment chromatography is used to enrich glycoproteins in CSF followed by trypsin digestion and subsequent LC-MS/MS for shotgun identification and label-free quantitation. RESULTS: Using an optimized submicrogram peptide separation with molecular weight cut-off filtration and an in house-constructed database, 645 peptides are identified. Glycoproteins are enriched by lectin affinity chromatography, resulting in 795 identified proteins. The discovery and alterations of proSAAS-derived peptides and transthyretin are described and their roles in AD are discussed. CONCLUSIONS AND CLINICAL RELEVANCE: Comprehensive identification of endogenous CSF peptidome is achieved. Fifteen proteins are found to be differentially expressed among the three groups. The dynamic changes of transthyretin are reported for the first time.
Authors: Gustaf Boström; Eva Freyhult; Johan Virhammar; Daniel Alcolea; Hayrettin Tumani; Markus Otto; Rose-Marie Brundin; Lena Kilander; Malin Löwenmark; Vilmantas Giedraitis; Alberto Lleó; Christine A F von Arnim; Kim Kultima; Martin Ingelsson Journal: J Alzheimers Dis Date: 2021 Impact factor: 4.472