In 2015, life expectancy at birth in Italy, according to the Organisation for Economic Co-operation and Development, was 82.07 years, positioning the country among the highest globally. As the population continues to age, the risk of developing geriatric syndromes, such as frailty, increases. Frailty is a complex syndrome characterized by a reduction in physiological reserves, leading to increased vulnerability to external stressors. Recent data indicate that approximately 15% of Europeans over the age of 65 are affected by frailty, with this figure rising to over 25% in those aged 85 and older. This study explores the role of diet, particularly the consumption of fruits and vegetables, in the progression of frailty in older adults through a dual approach: (i) validating hippuric acid (HA), a human-gut co-metabolite derived from polyphenol intake, as a biomarker of frailty linked to fruit and vegetable consumption, using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method validated according to European Medicines Agency (EMA) guidelines; (ii) investigate the association between food derived compounds and frailty by developing a mass spectrometry based nutrimetabolomics plasma profiling. Data and plasma samples were collected from the InveCe.Ab and InCHIANTI longitudinal studies to represent the older Italian population. A precise and sensitive method for quantifying HA in human plasma was developed. The application of this method showed that plasma HA levels were significantly higher in non-frail older adults compared to frail individuals in both cohorts. Longitudinal analyses confirmed these findings, showing a decline in HA levels over time in frail individuals. Furthermore, fruit and vegetable consumption was associated with higher HA levels. The analysis revealed that frail individuals reported lower consumption of fruits and vegetables compared to non-frail individuals. Mediation analysis from the last follow-up of the InveCe.Ab cohort suggested that HA may mediate the protective effects of a diet rich in fruits and vegetables against frailty, supporting the importance of a polyphenol-rich diet in older adults. To explore more complex dietary patterns, the nutrimetabolomic profile of a subpopulation of older adults in the InveCe.Ab cohort was evaluated. The proposed workflow integrates the use of a database of approximately 1,000 food-derived molecules (Food-Derived Compound, FDC) with the EASY-FIA platform, developed for pre-processing data obtained through an untargeted MSMS flow-injection analysis (FIA) approach. Applying this workflow to the InveCe.Ab subpopulation, 83 metabolites associated with food intake were identified, including caffeic acid, quercetin, and isorhamnetin, all plant-derived compounds, which discriminated between frail and non-frail individuals. Finally, we explored the levels of artificial sweeteners in human biofluids to obtain an overview of exposure to these compounds. Our systematic review revealed the presence of artificial sweeteners even in individuals who did not report consumption, suggesting pervasive exposure. Moreover, elevated plasma levels of erythritol and saccharin were associated with an increased risk of cardiovascular events and cognitive decline, in line with epidemiological studies that highlight the need for further research on the long-term effects of artificial sweetener exposure. In conclusion, this work highlights the complex relationship between diet, food-derived compounds, and the progression of frailty in older adults, demonstrating the potential of the nutrimetabolomic approach in identifying biomarkers, such as hippuric acid. The protective role of plant-derived compounds, such as polyphenols and flavonoids, further emphasizes the importance of a plant-based diet.

Nel 2015, l'aspettativa di vita alla nascita in Italia, secondo l’Organizzazione per la Cooperazione e lo Sviluppo Economico, era di 82,07 anni, posizionando il Paese tra i primi a livello globale. Con l'invecchiamento della popolazione, aumenta il rischio di sviluppare sindromi geriatriche, come la fragilità, una sindrome complessa caratterizzata da una riduzione delle riserve fisiologiche, che aumenta la vulnerabilità agli stress esterni. Dati recenti mostrano che circa il 15% degli europei sopra i 65 anni è affetto da fragilità, percentuale che supera il 25% negli ultra-ottantacinquenni. Il presente studio esplora il ruolo della dieta, in particolare il consumo di frutta e verdura, nella progressione della fragilità negli anziani con un duplice approccio: (i) validare l'acido ippurico (HA), un co-metabolita umano derivato dall'assunzione di polifenoli, come biomarcatore della fragilità legato al consumo di frutta e verdura, utilizzando un approccio di spettrometria di massa (MS) tandem (LC-MS/MS) validato secondo le linee guida dell'Agenzia Europea per i Medicinali; (ii) sviluppare un profilo nutrimetabolomico per indagare l'associazione tra composti derivanti dall’alimentazione e fragilità. Sono stati raccolti dati e campioni di plasma dagli studi longitudinali InveCe.Ab e InCHIANTI, per rappresentare la popolazione anziana italiana. È stato sviluppato un metodo accurato e sensibile per la quantificazione dell'HA nel plasma umano. L'applicazione di questo metodo ha dimostrato che i livelli di HA nel plasma sono significativamente più alti negli anziani non fragili rispetto a quelli fragili in entrambe le coorti. Analisi longitudinali hanno confermato questi risultati, mostrando un calo dei livelli di HA nei fragili nel tempo. Inoltre, il consumo di frutta e verdura è risultato associato a livelli più alti di HA. L'analisi del consumo di frutta e verdura ha evidenziato che gli individui fragili riportano un consumo inferiore rispetto ai non fragili. L'analisi di mediazione nell'ultimo follow-up della popolazione InveCe.Ab ha suggerito che l'HA possa mediare gli effetti protettivi di una dieta ricca di frutta e verdura contro la fragilità. Per esplorare modelli dietetici più complessi, è stato valutato il profilo nutrimetabolomico di una sottopopolazione di anziani nella coorte InveCe.Ab. Il workflow proposto integra l'uso di un database di circa 1.000 molecole derivate dagli alimenti (Food-Derived Compound, FDC) con la piattaforma EASY-FIA, sviluppata per il pre-processamento dei dati ottenuti utilizzando un approccio di MS untargeted in flow injection analysis (FIA). Applicando questo workflow sulla sottopopolazione dello studio InveCe.Ab, sono stati identificati 83 metaboliti associati all'assunzione alimentare, tra cui acido caffeico, quercetina e isoramnetina, derivati da alimenti vegetali, che discriminano tra fragili e non fragili. Infine, abbiamo esplorato i livelli di dolcificanti artificiali nei biofluidi umani per ottenere una panoramica dell'esposizione a questi composti. La nostra revisione sistematica ha rilevato la presenza di dolcificanti artificiali anche in individui che non ne avevano riportato il consumo, suggerendo una loro esposizione pervasiva. Inoltre, elevati livelli plasmatici di eritritolo e saccarina sono stati associati a un aumento del rischio di eventi cardiovascolari e declino cognitivo, in linea con studi epidemiologici che sottolineano la necessità di ulteriori ricerche sugli effetti a lungo termine. In conclusione, questo lavoro evidenzia la complessa relazione tra dieta, composti alimentari e progressione della fragilità negli anziani, dimostrando il potenziale dell'approccio nutrimetabolomico nell'identificazione di biomarcatori come l’HA. Il ruolo protettivo dei composti vegetali, come i polifenoli e i flavonoidi, enfatizza ulteriormente l'importanza di una dieta ricca di alimenti vegetali.

(2025). Mass spectrometry-based approaches for the identification of metabolic trajectories as sentinels of the frailty status in the elderly. (Tesi di dottorato, , 2025).

Mass spectrometry-based approaches for the identification of metabolic trajectories as sentinels of the frailty status in the elderly

DE SIMONE, GIULIA
2025

Abstract

In 2015, life expectancy at birth in Italy, according to the Organisation for Economic Co-operation and Development, was 82.07 years, positioning the country among the highest globally. As the population continues to age, the risk of developing geriatric syndromes, such as frailty, increases. Frailty is a complex syndrome characterized by a reduction in physiological reserves, leading to increased vulnerability to external stressors. Recent data indicate that approximately 15% of Europeans over the age of 65 are affected by frailty, with this figure rising to over 25% in those aged 85 and older. This study explores the role of diet, particularly the consumption of fruits and vegetables, in the progression of frailty in older adults through a dual approach: (i) validating hippuric acid (HA), a human-gut co-metabolite derived from polyphenol intake, as a biomarker of frailty linked to fruit and vegetable consumption, using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method validated according to European Medicines Agency (EMA) guidelines; (ii) investigate the association between food derived compounds and frailty by developing a mass spectrometry based nutrimetabolomics plasma profiling. Data and plasma samples were collected from the InveCe.Ab and InCHIANTI longitudinal studies to represent the older Italian population. A precise and sensitive method for quantifying HA in human plasma was developed. The application of this method showed that plasma HA levels were significantly higher in non-frail older adults compared to frail individuals in both cohorts. Longitudinal analyses confirmed these findings, showing a decline in HA levels over time in frail individuals. Furthermore, fruit and vegetable consumption was associated with higher HA levels. The analysis revealed that frail individuals reported lower consumption of fruits and vegetables compared to non-frail individuals. Mediation analysis from the last follow-up of the InveCe.Ab cohort suggested that HA may mediate the protective effects of a diet rich in fruits and vegetables against frailty, supporting the importance of a polyphenol-rich diet in older adults. To explore more complex dietary patterns, the nutrimetabolomic profile of a subpopulation of older adults in the InveCe.Ab cohort was evaluated. The proposed workflow integrates the use of a database of approximately 1,000 food-derived molecules (Food-Derived Compound, FDC) with the EASY-FIA platform, developed for pre-processing data obtained through an untargeted MSMS flow-injection analysis (FIA) approach. Applying this workflow to the InveCe.Ab subpopulation, 83 metabolites associated with food intake were identified, including caffeic acid, quercetin, and isorhamnetin, all plant-derived compounds, which discriminated between frail and non-frail individuals. Finally, we explored the levels of artificial sweeteners in human biofluids to obtain an overview of exposure to these compounds. Our systematic review revealed the presence of artificial sweeteners even in individuals who did not report consumption, suggesting pervasive exposure. Moreover, elevated plasma levels of erythritol and saccharin were associated with an increased risk of cardiovascular events and cognitive decline, in line with epidemiological studies that highlight the need for further research on the long-term effects of artificial sweetener exposure. In conclusion, this work highlights the complex relationship between diet, food-derived compounds, and the progression of frailty in older adults, demonstrating the potential of the nutrimetabolomic approach in identifying biomarkers, such as hippuric acid. The protective role of plant-derived compounds, such as polyphenols and flavonoids, further emphasizes the importance of a plant-based diet.
BIGINI, PAOLO
BRUNELLI, LAURA
Invecchiamento; Spettrometria; Fragilità; Biomarcatori; Nutrimetabolomica
Ageing; Mass spectrometry; Frailty; Biomarkers; Nutrimetabolomics
BIO/10 - BIOCHIMICA
English
22-gen-2025
37
2023/2024
embargoed_20270122
(2025). Mass spectrometry-based approaches for the identification of metabolic trajectories as sentinels of the frailty status in the elderly. (Tesi di dottorato, , 2025).
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/538861
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