Knowledge of the time of deposition is pivotal in forensic investigations. Recent studies show that changes in intrinsic fluorescence over time can be used to estimate the age of body fluids. These changes have been attributed to oxidative modifications caused by protein–lipid interactions. This pilot study aims to explore the impact of these modifications on body fluid fluorescence, enhancing the protein–lipid model system for age estimation. Lipid and protein oxidation markers, including protein carbonyls, dityrosine, advanced glycation end-products (AGEs), malondialdehyde (MDA), and 4-hydroxynonenal (HNE), were studied in aging semen, urine, and saliva over 21 days. Surface plasmon resonance imaging (SPRi), enzyme-linked immunosorbent assay (ELISA), and fluorescence spectroscopy were applied. Successful detection of AGE, dityrosine, MDA, and HNE occurred in semen and saliva via SPRi, while only dityrosine was detected in urine. Protein carbonyls were measured in all body fluids, but only in saliva was a significant increase observed over time. Additionally, protein fluorescence loss and fluorescent oxidation product formation were assessed, showing significant decreases in semen and saliva, but not in urine. Although optimization is needed for accurate quantification, this study reveals detectable markers for protein and lipid oxidation in aging body fluids, warranting further investigation.
MULTIFILE
De samenwerking tussen de onderzoeksgroep FRIA van de Vrije Universiteit Brussel, afdeling oudergeneeskunde van het UMCG Groningen en de onderzoeksgroep (lectoraat) Healthy Ageing, Allied health Care and Nursing van de Hanzehogeschool Groningen is gericht op onderzoek naar bewegingsstoornissen bij veroudering. In het bijzonder wordt gekeken naar paratonic, een bewegingsstoornis bij dementie.The International Joint Research group ‘Move in Age’ concluded in a systematic review that paratonia still is a barely understood and devastating phenomenon in dementia and revealed the urgency of gaining more insight in the pathophysiology. Paratonia, a distinctive change in muscle tone, starts in early stages of dementia and develops further with progress of the disease. Resulting in severe discomfort for patients, but also affecting caregivers since daily care becomes increasingly difficult. It is hypothesized that changes in motor control due to dementia influences peripheral neurological control and biomechanical muscle structures (by crosslinking and inflammation caused by advanced glycation end-products (AGEs).This IJRG started in 2018 and aims to develop a long-term comprehensive research program on movement-related impairments at higher age. The three partners have a strong track record on research in the area of movement-related impairments in older persons; however, each focusing on a specific aspect. In fact, the Frailty in Ageing research group (FRIA) of the Vrije Universiteit Brussel (VUB) is running focused research program on the triad sarcopenia-dynapenia-inflammation with mainly a bio-gerontological and bio-psycho-medical approach; the department of General Practice and Elderly Care Medicine of the University Medical Center Groningen (UMCG) has anongoing research line on the medical aspects of mobility impairments in frail elderly persons and in elderly dementia patients; and finally Research Group Healthy Ageing, Allied Health Care and Nursing of the Hanze University of Applied Sciences Groningen (HUAS) developed a research program on physical, psycho-cognitive and social dimensions of frailty including the functional impact of mobility impairments. In the first 3-5 years, the focus will be on the movement-related impairments that occur in patients with dementia and in specific on paranoia. The programme will be extended towards movement-related impairments in the context of other geriatric syndromes.