Age-Related Fourier-Transform Infrared Spectroscopic Changes in Protein Conformation in an Aging Model of Human Dermal Fibroblasts

Abstract

The loss of proteostasis, which results in the accumulation of misfolded proteins, is one of the hallmarks of aging and is frequently associated with the aging process. Fibroblasts are a cellular model widely used in the study of aging and can mimic the loss of proteostasis that occurs in the human body. When studying human aging using fibroblasts, two approaches can be used: fibroblasts from the same donor aged in vitro until senescence or fibroblasts from donors of different ages. A previous study by our group showed that the first approach can be used in the study of aging. Thus, this work aimed to study the spectroscopic profile of human dermal fibroblasts from four donors of different ages using Fourier-transform infrared spectroscopy to identify changes in protein conformation and to compare results with those obtained in the previous study. Partial least squares regression analysis and peak intensity analysis suggested that fibroblasts from older donors were characterized by an increase in the levels of antiparallel β-sheets and a decrease in intermolecular β-sheets, in agreement with our previous results.

Changes in Hemoglobin Properties in Complex with Glutathione and after Glutathionylation

“…A decrease in the relative amplitude of Amide I compared with the amplitude of the Amide II band, which is significantly less dependent on the secondary structure of the protein, may indicate a decrease in the relative content of alpha helices due to an increase in the proportion of other types of secondary structure (beta layers or disordered structure). The ratio of Amide I/Amide II amplitudes was used in [26] to estimate the change in the proportion of beta structures in the protein composition. In this study, we chose the Amide I/Amide II amplitude ratio as an indicator of the proportion of alpha structures in the composition of hemoglobin.…”

Biomolecular alterations detected in multiple sclerosis skin fibroblasts using Fourier transform infrared spectroscopy

“…Molecules including lipids, proteins, nucleic acids (phosphate), and carbohydrates within biospecimens give unique vibrational frequencies, which change with structure, composition, and functional groups ( Talari et al, 2017 ). Indeed, interrogation of skin fibroblasts and tissue by FTIR spectroscopy has detected altered biomolecules and processes that inform on aging, cancer, muscular dystrophy, quiescence, neurological disorders, and oxidation ( Kosoglu et al, 2017 ; Kyriakidou et al, 2017 ; Eberhardt et al, 2018 ; Martel et al, 2020 ; Mateus et al, 2021 ; Martins et al, 2023 ). Therefore, characterization of biochemical changes of MS skin fibroblasts may inform on pathophysiological mechanisms involved in the disease, as well as provide a potential alternative site to detect and monitor early biomolecular alterations.…”