Fourier Transform Infrared (FTIR) Spectroscopy, in particular ATR-FTIR, is a widely used technique that allows, in a very short time, to screen biological samples and to identify its specific spectral signature, being an important tool for clinical diagnosis and biomarker discovery. FTIR spectroscopy is used to screen cells, tissues and biofluids and is already implemented in biomedicine, mainly in pre-clinical setting. Although the experimental procedure is easy to implement, sample preparation, definition of spectra acquisition parameters and spectral analysis are crucial steps to obtain reliable and reproducible results. However, the selection of experimental conditions for spectral analysis can be a difficult task for researchers because the information is dispersed and often the choice is made in an empirical and inaccurate way. This review gathers and summarizes studies using FTIR in pre-clinical and clinical setting and aims to systematize information and propose some guidelines for FTIR spectroscopy studies of biological samples. This will help new users to prepare samples for FTIR analysis and understand the critical steps to correctly perform spectra pretreatment, preprocessing and statistical analysis and to implement appropriate and evidence-based experimental designs.

Alzheimer’s disease (AD) diagnosis is based on psychological and imaging tests but can also include monitoring cerebrospinal fluid (CSF) biomarkers. However, CSF based-neurochemical approaches are expensive and invasive, limiting their use to well-eq

Myotonic dystrophy type 1 (DM1) is a hereditary disease characterized by progressive distal muscle weakness and myotonia. Patients with DM1 have abnormal lipid metabolism and a high propensity to develop a metabolic syndrome in comparison to the general population. It follows that metabolome evaluation in these patients is crucial and may contribute to a better characterization and discrimination between DM1 disease phenotypes and severities. Several experimental approaches are possible to carry out such an analysis; among them is Fourier-transform infrared spectroscopy (FTIR) which evaluates metabolic profiles by categorizing samples through their biochemical composition. In this study, FTIR spectra were acquired and analyzed using multivariate analysis (Principal Component Analysis) using skin DM1 patient-derived fibroblasts and controls. The results obtained showed a clear discrimination between both DM1-derived fibroblasts with different CTG repeat length and with the age of disease onset; this was evident given the distinct metabolic profiles obtained for the two groups. Discrimination could be attributed mainly to the altered lipid metabolism and proteins in the 1800–1500 cm⁻¹ region. These results suggest that FTIR spectroscopy is a valuable tool to discriminate both DM1-derived fibroblasts with different CTG length and age of onset and to study the metabolomic profile of patients with DM1.

Cancer is one of the leading causes of death worldwide and so the development of strategies for an early diagnosis of cancer is of great importance. Since biochemical alterations precede morphological changes in cells and tissues, studying cancer metabolome seems like a reasonable approach for early diagnosis, prognosis and to follow treatment progression. Fourier Transform Infrared (FTIR) spectroscopy is a valuable tool for studying the metabolome of biological samples, such as cancer cell lines. Unlike staining procedures and other histopathologic approaches, this technique is rapid, non-destructive and does not require reagents. The spectral differences that result from probing the biochemical composition of cancer and normal cells are indicative of distinct metabolic profiles, which allows for the discrimination of different cells. Using FTIR spectroscopy and multivariate statistical analysis, several alterations concerning the content of lipids, proteins, nucleic acids and carbohydrates have been identified in cancer cells, some of which can be regarded as potential biomarkers. This review focuses on FTIR spectroscopy as a metabolomics tool to study and characterize cancer cell lines.

The world is aging and we must face the challenges that this brings. One of the reasons for the increasing aging of the world’s population is the increase in life expectancy and, since we live longer, it is of paramount importance to live well and to prevent age-associated diseases. In this way, it is crucial to improve knowledge of the aging process and of the mechanisms that contribute to it. Ideally it would be of great interest to have a panel of biomarkers of healthy aging that would allow an estimate of the biological age of an individual. One of the changes that greatly contribute to aging is the loss of protein homeostasis, also called proteostasis. To ensure the proper function of cells and to maintain cellular proteostasis, organisms have developed systems to control protein synthesis, folding and degradation. Loss or dysfunction of proteostasis is at the root of many well-studied human neurological diseases, such as Alzheimer’s disease and, more recently, it has been implicated in the aging process with some reports showing long-lived animals to have improved proteostasis. Growing evidence suggests a strong link between modifications in the quantity and/or activity of several players involved in proteostasis and longevity. In this review, we give an overview of the main characteristics of aging with focus on proteostasis. We present how changes in components of proteostasis, during aging, impact the lifespan of model organisms. We also briefly review the current state of aging biomarkers and discuss the potential of proteostasis network components as markers of healthy aging.