A universal biomarker of cellular ageing in eukaryotic postmitotic cells is the appearance over time of autofluorescent lysosomal residual bodies called age pigments or lipofuscin granules. Their role in the process of cellular ageing has been debated without resolution. Neither the identity nor mechanism of formation of the fluorophores has been definitively determined. A postmitotic cell type that accumulates large quantities of age pigments is the ocular retinal pigment epithelium. We have now identified the major orange-emitting fluorophore of these pigments using fast-atom bombardment tandem mass spectrometry with collisional activation analysis. It is an amphoteric quaternary amine that arises as a Schiff base reaction product of retinaldehyde and ethanolamine. This compound should display lysosomotropic detergent behaviour which would help explain many of the age-related changes shown in this cell. These results suggest a new role for Schiff base reaction products as lysosomotropic amines in the genesis of cellular age pigments.
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http://dx.doi.org/10.1038/361724a0 | DOI Listing |
Science
January 2025
Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland.
The origins and prehistory of domestic sheep () are incompletely understood; to address this, we generated data from 118 ancient genomes spanning 12,000 years sampled from across Eurasia. Genomes from Central Türkiye ~8000 BCE are genetically proximal to the domestic origins of sheep but do not fully explain the ancestry of later populations, suggesting a mosaic of wild ancestries. Genomic signatures indicate selection by ancient herders for pigmentation patterns, hornedness, and growth rate.
View Article and Find Full Text PDFPharmacol Rep
January 2025
Razi Drug Research Centre, Iran University of Medical Sciences (IUMS), Tehran, Iran.
Melatonin, renowned for regulating sleep-wake cycles, also exhibits notable anti-aging properties for the skin. Synthesized in the pineal gland and various tissues including the skin, melatonin's efficacy arises from its capacity to combat oxidative stress and shield the skin from ultraviolet (UV)-induced damage. Moreover, it curbs melanin production, thereby potentially ameliorating hyperpigmentation.
View Article and Find Full Text PDFAdv Drug Deliv Rev
January 2025
Neurodegenerative Diseases Department, Kadimastem Ltd, Pinchas Sapir 7, Weizmann Science Park, Ness-Ziona, Israel; Department of Molecular Genetics, Weizmann Institute of Science, 76100, Rehovot, Israel.
Self-renewal capacity and potential to differentiate into almost any cell type of the human body makes pluripotent stem cells a valuable starting material for manufacturing of clinical grade cell therapies. Neurodegenerative diseases are characterized by gradual loss of structure or function of neurons, often leading to neuronal death. This results in gradual decline of cognitive, motor, and physiological functions due to the degeneration of the central nervous systems.
View Article and Find Full Text PDFAm J Ophthalmol
January 2025
Centre for Public Health, Faculty of Medicine and Health Sciences, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom. Electronic address:
Purpose: Color imaging is the accepted reference standard for detection of macular fibrosis in neovascular age-macular degeneration. Other imaging modalities of fluorescein angiography (FA) and spectral domain optical coherence tomography (SD-OCT) are also used but no formal agreement studies exist. We evaluated the agreement between fibrosis on colour, FA and SD-OCT-detected hyperreflective material (HRM) and their clinical relevance.
View Article and Find Full Text PDFPreviously we reported color matches measured in young adults using a newly developed multi-wavelength LED-based visual trichromator with which we estimated their individual L-, M- and S-cone spectral sensitivities. Here, we extend those measurements to include 70 additional observers aged between 8 to 80 years. As in our previous work, a series of color matching measurements were made to a reference white.
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