The capacity to deal with stress declines during the aging process, and preservation of cellular stress responses is critical to healthy aging. The unfolded protein response of the endoplasmic reticulum (UPR) is one such conserved mechanism, which is critical for the maintenance of several major functions of the ER during stress, including protein folding and lipid metabolism. Hyperactivation of the UPR by overexpression of the major transcription factor, , solely in neurons drives lifespan extension as neurons send a neurotransmitter-based signal to other tissue to activate UPR in a non-autonomous fashion.
View Article and Find Full Text PDFMechanical stress is a measure of internal resistance exhibited by a body or material when external forces, such as compression, tension, bending, etc. are applied. The study of mechanical stress on health and aging is a continuously growing field, as major changes to the extracellular matrix and cell-to-cell adhesions can result in dramatic changes to tissue stiffness during aging and diseased conditions.
View Article and Find Full Text PDFSmall molecule inhibitors of the mitochondrial electron transport chain (ETC) hold significant promise to provide valuable insights to the field of mitochondrial research and aging biology. In this study, we investigated two molecules: mycothiazole (MTZ) - from the marine sponge C. mycofijiensis and its more stable semisynthetic analog 8-O-acetylmycothiazole (8-OAc) as potent and selective chemical probes based on their high efficiency to inhibit ETC complex I function.
View Article and Find Full Text PDFThe nervous system plays a critical role in maintaining whole-organism homeostasis; neurons experiencing mitochondrial stress can coordinate the induction of protective cellular pathways, such as the mitochondrial unfolded protein response (UPR), between tissues. However, these studies largely ignored nonneuronal cells of the nervous system. Here, we found that UPR activation in four astrocyte-like glial cells in the nematode, , can promote protein homeostasis by alleviating protein aggregation in neurons.
View Article and Find Full Text PDFThe nervous system plays a critical role in maintaining whole-organism homeostasis; neurons experiencing mitochondrial stress can coordinate the induction of protective cellular pathways, such as the mitochondrial unfolded protein response (UPR), between tissues. However, these studies largely ignored non-neuronal cells of the nervous system. Here, we found that UPR activation in four, astrocyte-like glial cells in the nematode, , can promote protein homeostasis by alleviating protein aggregation in neurons.
View Article and Find Full Text PDFCellular senescence may be associated with morphological changes in skeletal muscle and changes in physical function with age although there have been few human studies. We aimed to determine the feasibility of characterising cellular senescence in skeletal muscle and explored sex-specific associations between markers of cellular senescence, muscle morphology, and physical function in participants from the MASS_Lifecourse Study. Senescence markers (p16, TAF (Telomere-Associated DNA Damage Foci), HMGB1 (High Mobility Group Box 1), and Lamin B1) and morphological characteristics (fibre size, number, fibrosis, and centrally nucleated fibres) were assessed in muscle biopsies from 40 men and women (age range 47-84) using spatially-resolved methods (immunohistochemistry, immunofluorescence, and RNA and fluorescence in situ hybridisation).
View Article and Find Full Text PDFSenescence is a cell fate that contributes to multiple aging-related pathologies. Despite profound age-associated changes in skeletal muscle (SkM), whether its constituent cells are prone to senesce has not been methodically examined. Herein, using single cell and bulk RNA-sequencing and complementary imaging methods on SkM of young and old mice, we demonstrate that a subpopulation of old fibroadipogenic progenitors highly expresses together with multiple senescence-related genes and, concomitantly, exhibits DNA damage and chromatin reorganization.
View Article and Find Full Text PDFCellular senescence is characterized by an irreversible cell cycle arrest as well as a pro-inflammatory phenotype, thought to contribute to aging and age-related diseases. Neutrophils have essential roles in inflammatory responses; however, in certain contexts their abundance is associated with a number of age-related diseases, including liver disease. The relationship between neutrophils and cellular senescence is not well understood.
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