title: Increased levels of hyper-stable protein aggregates in plasma of older adults.
abstract: Proteins that misfold into hyper-stable/degradation-resistant species during aging may accumulate and disrupt protein homeostasis (i.e., proteostasis), thereby posing a survival risk to any organism. Using the method diagonal two-dimensional (D2D) SDS-PAGE, which separates hyper-stable SDS-resistant proteins at a proteomics level, we analyzed the plasma of healthy young (<30 years) and older (60-80 years) adults. We discovered the presence of soluble SDS-resistant protein aggregates in the plasma of older adults, but found significantly lower levels in the plasma of young adults. We identified the inflammation-related chaperone protein haptoglobin as the main component of the hyper-stable aggregates. This observation is consistent with the growing link between accumulations of protein aggregates and aging across many organisms. It is plausible higher amounts of SDS-resistant protein aggregates in the plasma of older adults may reflect a compromise in proteostasis that may potentially indicate cellular aging and/or disease risk. The results of this study have implications for further understanding the link between aging and the accumulation of protein aggregates, as well as potential for the development of aging-related biomarkers. More broadly, this novel application of D2D SDS-PAGE may be used to identify, quantify, and characterize the degradation-resistant protein aggregates in human plasma or any biological system.
authors.affiliation: Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA.|Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA.
authors.forename: Ke
authors.initials: K
authors.lastname: Xia
authors.affiliation: Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA.|Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA.
authors.forename: Hannah
authors.initials: H
authors.lastname: Trasatti
authors.affiliation: Albany Medical Center, 43 New Scotland Avenue, Albany, NY, 12208, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Wymer
authors.affiliation: Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA. colonw@rpi.edu.|Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA. colonw@rpi.edu.
authors.forename: Wilfredo
authors.initials: W
authors.lastname: Colón
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006706:Homeostasis; D006801:Humans; D008297:Male; D008875:Middle Aged; D046988:Proteasome Endopeptidase Complex / Q000097:blood*; D066329:Protein Aggregates / Q000502:physiology*; D011506:Proteins / Q000378:metabolism*; D055815:Young Adult
chemical_list: D066329:Protein Aggregates; D011506:Proteins; D046988:Proteasome Endopeptidase Complex
keywords: Haptoglobin; Inflammation; Kinetic stability; SDS-resistant